[House Hearing, 117 Congress]
[From the U.S. Government Publishing Office]


                         CLIMATE CHANGE AND THE U.S. 
                      AGRICULTURE AND FORESTRY SECTORS

=======================================================================
                                 HEARING

                               BEFORE THE

                        COMMITTEE ON AGRICULTURE
                        HOUSE OF REPRESENTATIVES

                    ONE HUNDRED SEVENTEENTH CONGRESS

                             FIRST SESSION

                               __________

                           FEBRUARY 25, 2021

                               __________

                            Serial No. 117-1


          Printed for the use of the Committee on Agriculture
                         agriculture.house.gov

[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

                               __________
                               

                    U.S. GOVERNMENT PUBLISHING OFFICE                    
44-956 PDF                  WASHINGTON : 2021                     
          
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                        COMMITTEE ON AGRICULTURE

                     DAVID SCOTT, Georgia, Chairman

JIM COSTA, California                GLENN THOMPSON, Pennsylvania, 
JAMES P. McGOVERN, Massachusetts     Ranking Minority Member
FILEMON VELA, Texas                  AUSTIN SCOTT, Georgia
ALMA S. ADAMS, North Carolina, Vice  ERIC A. ``RICK'' CRAWFORD, 
Chair                                Arkansas
ABIGAIL DAVIS SPANBERGER, Virginia   SCOTT DesJARLAIS, Tennessee
JAHANA HAYES, Connecticut            VICKY HARTZLER, Missouri
ANTONIO DELGADO, New York            DOUG LaMALFA, California
BOBBY L. RUSH, Illinois              RODNEY DAVIS, Illinois
CHELLIE PINGREE, Maine               RICK W. ALLEN, Georgia
GREGORIO KILILI CAMACHO SABLAN,      DAVID ROUZER, North Carolina
Northern Mariana Islands             TRENT KELLY, Mississippi
ANN M. KUSTER, New Hampshire         DON BACON, Nebraska
CHERI BUSTOS, Illinois               DUSTY JOHNSON, South Dakota
SEAN PATRICK MALONEY, New York       JAMES R. BAIRD, Indiana
STACEY E. PLASKETT, Virgin Islands   JIM HAGEDORN, Minnesota
TOM O'HALLERAN, Arizona              CHRIS JACOBS, New York
SALUD O. CARBAJAL, California        TROY BALDERSON, Ohio
RO KHANNA, California                MICHAEL CLOUD, Texas
AL LAWSON, Jr., Florida              TRACEY MANN, Kansas
J. LUIS CORREA, California           RANDY FEENSTRA, Iowa
ANGIE CRAIG, Minnesota               MARY E. MILLER, Illinois
JOSH HARDER, California              BARRY MOORE, Alabama
CYNTHIA AXNE, Iowa                   KAT CAMMACK, Florida
KIM SCHRIER, Washington              MICHELLE FISCHBACH, Minnesota
JIMMY PANETTA, California            ------
ANN KIRKPATRICK, Arizona
------

                                 ______

                      Anne Simmons, Staff Director

                 Parish Braden, Minority Staff Director
                            
                            C O N T E N T S

                              ----------                              
                                                                   Page
Bustos, Hon. Cheri, a Representative in Congress from Illinois, 
  submitted statement............................................   383
Costa, Hon. Jim, a Representative in Congress from California, 
  prepared statement.............................................     6
    Submitted letters on behalf of:
        Mulhern, Jim, President and Chief Executive Officer, 
          National Milk Producers Federation.....................   329
        Center for Food Safety, et al............................   330
        National Cattlemen's Beef Association, et al.............   332
Panetta, Hon. Jimmy, a Representative in Congress from 
  California, submitted letters..................................   388
Pingree, Hon. Chellie, a Representative in Congress from Maine, 
  prepared statement.............................................     6
    Submitted report.............................................   333
Schrier, Hon. Kim, a Representative in Congress from Washington, 
  submitted letter...............................................   387
Scott, Hon. David, a Representative in Congress from Georgia, 
  opening statement..............................................     1
    Prepared statement...........................................     2
    Submitted articles...........................................   131
    Submitted reports............................................   214
    Submitted letters on behalf of:
        Hanson, Ph.D., Chad, Chief Scientist and Director; 
          Jennifer Mamola, D.C. Forest Protection Advocate, John 
          Muir Project...........................................   215
        Linder, John, President, National Corn Growers 
          Association............................................   220
        Olson, Julia, Executive Director, Our Children's Trust...   223
        Agricultural Retailers Association, et al................   289
        American Society of Agronomy, et al......................   291
        Biotechnology Innovation Organization....................   295
    Submitted statements on behalf of:
        Glenn, Ph.D., Barbara P., Chief Executive Officer, 
          National Association of State Departments of 
          Agriculture............................................   326
        BASF Corporation.........................................   327
Thompson, Hon. Glenn, a Representative in Congress from 
  Pennsylvania, opening statement................................     3

                               Witnesses

Cantore, Jim, Senior Meteorologist, The Weather Channel, Atlanta, 
  GA.............................................................     8
    Prepared statement...........................................     9
    Submitted questions..........................................   393
Knox, Pamela N., Director, University of Georgia Weather Network; 
  Agricultural Climatologist, UGA Cooperative Extension, Athens, 
  GA.............................................................    11
    Prepared statement...........................................    13
    Submitted questions..........................................   394
Duvall, Zippy, President, American Farm Bureau Federation, 
  Washington, D.C................................................    23
    Prepared statement...........................................    25
    Submitted questions..........................................   397
Brown, Gabe, Co-Owner/Operator, Brown's Ranch, Bismarck, ND......    27
    Prepared statement...........................................    29
    Submitted questions..........................................   399
Shellenberger, Michael D., Founder and President, Environmental 
  Progress, Berkeley, CA.........................................    43
    Prepared statement...........................................    45
    Submitted questions..........................................   399
 
         CLIMATE CHANGE AND THE U.S. AGRICULTURE AND FORESTRY SECTORS

                              ----------                              


                      THURSDAY, FEBRUARY 25, 2021

                          House of Representatives,
                                  Committee on Agriculture,
                                                   Washington, D.C.
    The Committee met, pursuant to call, at 12:58 p.m., via 
Webex, Hon. David Scott of Georgia [Chairman of the Committee] 
presiding.
    Members present: Representatives David Scott of Georgia, 
Costa, McGovern, Adams, Spanberger, Hayes, Delgado, Rush, 
Pingree, Kuster, Bustos, Plaskett, O'Halleran, Carbajal, 
Lawson, Correa, Craig, Harder, Axne, Schrier, Panetta, 
Thompson, Austin Scott of Georgia, Crawford, DesJarlais, 
Hartzler, LaMalfa, Davis, Allen, Rouzer, Kelly, Bacon, Johnson, 
Baird, Hagedorn, Jacobs, Balderson, Cloud, Mann, Feenstra, 
Miller, Moore, Cammack, and Fischbach.
    Staff present: Lyron Blum-Evitts, Melinda Cep, Ross 
Hettervig, Prescott Martin III, Felix Muniz, Jr., Anne Simmons, 
Ashley Smith, Anna Brightwell, Josh Maxwell, Ricki Schroeder, 
Patricia Straughn, Erin Wilson, and Dana Sandman.

  OPENING STATEMENT OF HON. DAVID SCOTT, A REPRESENTATIVE IN 
                     CONGRESS FROM GEORGIA

    The Chairman. This hearing of the Committee of Agriculture 
entitled, Climate Change and the U.S. Agriculture and Forestry 
Sectors, will now come to order.
    I want to welcome and thank everyone for joining this most 
important, timely, critical, and extraordinarily necessary 
hearing today. After brief opening remarks, Members will 
receive testimony from today's witnesses, and then the hearing 
will be opened up to questions and discussions. Members will be 
recognized in order of seniority, alternating between Majority 
and Minority Members, and in order of arrival for those Members 
who have joined us after the hearing was called to order. And 
as normal, when you are recognized, you will be asked to unmute 
your microphone, and will have 5 minutes to ask your questions 
or make a statement. If you are not speaking, I will greatly 
ask that you remain muted in order to minimize the background 
noise. In order to get in as many questions as possible, the 
timer will stay consistently visible on the screen to let you 
know how much time you have.
    And now, ladies and gentlemen, let me open this up with a 
few remarks here myself.
    This is perhaps the single-most important hearing that we 
must have right now, because agriculture is our single-most 
important industry overall, but especially right now, because 
nobody: our farmers, our agriculture industry, they more than 
any other entity or industry suffer more and benefit more from 
climate and weather. And I say it is our most important 
industry because of this: agriculture is the food we eat, it is 
the water we drink, it is the clothes we wear, and it is our 
shelter. Now, folks, we can do without a lot of things, but we 
definitely can't do without food, water, clothing, the 
necessities. And we have lost too many of our farms because we 
moved too late to get the right information in about these 
weather patterns. And so, I am so grateful for our Committee, 
our staff, that has assembled a wonderful panel. I am so 
thrilled to be able to approach this issue with my partner and 
my friend, Ranking Member Thompson. This is critical.
    And so, I just want us to move with this with an open heart 
and an open mind, and to know that the American people are 
watching us. It is agriculture that is at the point of the 
spear when it comes to climate change. I am so grateful for the 
talented Members of this Committee who are willing to take this 
issue on and provide the critical leadership to deal with 
climate change, to secure our food supply, and save our farms.
    [The prepared statement of Mr. David Scott follows:]

 Prepared Statement of Hon. David Scott, a Representative in Congress 
                              from Georgia
    Good morning, I'm excited to be here today for our first full 
Committee hearing and in particular to begin work on what is without a 
doubt the greatest challenge before us--climate change. I am also 
excited for the opportunity to work with my colleague, Ranking Member 
Thompson of Pennsylvania this Congress as he joins me in launching our 
first hearing together.
    The U.S. agriculture sector is amongst the most productive in the 
world, contributing over $136 billion to the U.S. economy and directly 
supporting 2.6 million jobs. The U.S. forestry sector is another 
economic engine. In 2020, that sector manufactured $300 billion in 
forest products and employed approximately 940,000 people.
    Over the past century, long-term changes in weather patterns have 
driven major changes across the globe, including the very landscapes 
that support these sectors. Since 1880, the average global temperature 
has increased about 2 F. Increased temperatures have accompanied 
changes in rainfall patterns and more frequent climatic extremes. Most 
recently, the National Oceanic and Atmospheric Administration declared 
2020 as the second warmest year on record, after 2016.
    These changes introduce significant risks to agricultural 
production, forest resources, and the economy. These risks cannot be 
understated. According to USDA's Economic Research Service, climate 
change will likely affect risk-management tools, financial markets, and 
our global food security, among other important areas.
    Our farmers, ranchers, and forest managers understand these risks, 
and they are the first to experience the pressures of a changing 
climate. But American producers are resilient, and many are already 
adopting production practices that not only improve productivity but 
store carbon and reduce emissions in the atmosphere. And yet there is 
tremendous opportunity to do more. It is incumbent on this Committee to 
ensure producers have the financial and technical resources they need 
to understand climate risks, consider mitigation strategies, and 
receive the support they need to make important investments in their 
operations.
    I am excited to have such a broad range of witnesses to discuss 
these points today. I am also eager to hear how we may improve upon 
current policy and scale existing investments in proportion to the 
magnitude of the challenge. I look forward to your testimony.
    With that I would like to invite our Ranking Member, Mr. Thompson, 
for any opening remarks.

    The Chairman. With that, I want to turn it over to the 
Ranking Member, the distinguished Member from Pennsylvania, 
Ranking Member Thompson.

 OPENING STATEMENT OF HON. GLENN THOMPSON, A REPRESENTATIVE IN 
                   CONGRESS FROM PENNSYLVANIA

    Mr. Thompson. Well, good afternoon everybody, and I would 
like to thank the Chairman for holding today's hearing, and his 
flexibility due to the updated floor schedule.
    The impact that climate has on agriculture production and 
on our natural resources is an issue of great importance to all 
of us on the House Agriculture Committee. Working with us--and 
Mr. Chairman, thank you for working with us on a mutually 
agreeable time that provides for greater Member participation. 
It is valued and very much appreciated. I would also like to 
thank the witnesses who juggled their schedules to join us 
today virtually, and I would like to thank all of our 
constituents, the stakeholders who are joining us today 
virtually as well.
    Now, there is a saying I learned B.C. (Before Congress). If 
you are not at the table, you are probably on the menu. And for 
too long, the agriculture sector has been on the menu when it 
comes to climate. The hearing today begins to pull us up to the 
table.
    I would like to start my remarks by making a very clear 
position: the climate is changing. The Earth's temperature is 
rising. I trust the science that globally industrial activity 
has contributed to the issue. Reducing global emissions is what 
we should be pursuing. It is the right thing to do, and it 
requires smart, prudent, and science-based policies.
    But the apocalyptic narrative of the world coming to an end 
within a decade is not evidence-based and it is not supported 
by science. The self-proclaimed experts who continue to spout 
this impending doomsday scenario do nothing to advance the 
climate solutions discourse. They only cause unnecessary public 
angst and anxiety. It divides lawmakers when what we need is 
collaboration.
    I imagine these climate grifters must rely on scare tactics 
to push their extreme agenda because it is burdensome, 
overreaching, and negatively affects jobs and rural economies. 
Not to mention the likelihood these policies could actually 
result in higher global emissions, and I will touch more on 
this in just a second.
    Just over a decade ago, Congress rejected the Waxman-Markey 
Cap and Trade, and for those who weren't around or need 
reminding, this legislation was a national energy tax. 
Estimates vary, but experts predicted under Cap and Trade 
proposals, energy prices would increase as much as 125 percent. 
It was predicted that this policy would have resulted in 
American farm income dropping by $8 billion in 2012, $25 
billion in 2024, and $50 billion in 2035. Decreases of 28, 60, 
and 94 percent respectively. This underscores the most 
troubling aspect of a national Cap and Trade system, or other 
similar approaches, which is that 40 to 60 million acres of 
land would likely have to shift from crop production and 
planted to trees.
    It is worth noting, largely due to the innovations in free 
market principles, the United States has reduced emissions 
comparable to, if not better than, what Waxman-Markey called 
for in its out-year reduction targets.
    Equally important, because it was not through government 
prescriptive measures, energy costs on average have come down. 
With Waxman-Markey energy prices would have skyrocketed. When 
Waxman-Markey failed, the Obama EPA chose a different route and 
pursued regulations to reduce emissions from the electricity 
sector known as the Clean Power Plan. Fortunately, that was 
stopped by the courts and eventually, the Trump EPA. Good 
thing, too. The government prescriptive Obama Clean Power Plan 
sought to reduce emissions 32 percent below 2005 levels by 
2030. Without this regulation, and because of innovation and 
the market, power sector emissions hit that 32 percent 
reduction mark more than a decade sooner in 2019, without the 
utility bill increases that would have come with the Clean 
Power Plan.
    Now, at a time when energy prices have decreased and 
manufacturing has strengthened, United States has led the world 
in reducing emissions. We have reduced carbon emissions more 
than the next 12 emission-reducing nations combined.
    Now, let me quote the head of the International Energy 
Agency: `` . . . in the last 10 years, the emissions reductions 
in the United States has been the largest in the history of 
energy . . . This is a huge decline of emissions.'' \1\ Now, 
the question isn't whether or not climate change is real; the 
question is not whether or not to reduce emissions. The 
question is how to best approach it?
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    \1\ Editor's note: this quotation originates from the facebook 
video feed, Secretary Perry Holds a Joint Press Conference with IEA 
Executive Director Fatih Birol and is available at https://
www.facebook.com/SecretaryPerry/videos/835183026823612/.
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    In just this past Congress, Democrats created a Select 
Committee on Climate Crisis, which used nearly an entire 
Congress only to deliver a staff report that simply rebranded 
Cap and Trade as the Green New Deal. Now, these climate 
approaches aimed to uproot the basic underpinnings of our 
farming, manufacturing, energy, and transportation systems, and 
requires changes for marginal or no benefits which would have 
significant implications for the profitability of U.S. 
agriculture and the U.S. economy, and specifically, the rural 
economy. More so, these recommendations can negatively impact 
food abundance and increase food prices all while displacing 
U.S. production with that of less efficient, more carbon 
intensive, foreign producers, leading to an increase in global 
emissions.
    Now, these proposals were in direct conflict with the 
bipartisan principle that on-farm conservation should be 
locally led, voluntary, and incentive-based, principles that 
this Committee has put forward and really has been led by.
    I truly believe our approach to overcoming this issue must 
favor pro-growth solutions over burdensome over-regulations. 
Innovation and research must be at the forefront of our 
solutions. As a matter of fact, there has been a lot of talk 
about legislation or Executive action to address climate 
change, but I believe many of these approaches are a solution 
in search of a problem. If we really want to reduce global 
emissions, hindering U.S. production is the opposite of what we 
should be doing. We should be taking steps to ensure the global 
competitiveness of our farmers.
    Now, though often overlooked, the 2018 Farm Bill is 
arguably the greenest farm bill ever, and the farm bill is a 
climate bill. Some may scoff at that assertion, but let's talk 
about that bill. The farm bill's voluntary programs help 
farmers implement new practices that sequester carbon, reduce 
emissions, and adopt more energy-efficient farming practices. 
These programs have grown significantly in size and scope over 
the past 2 decades, providing $6 billion a year to farmers, 
ranchers, and forest owners to implement practices like soil 
health practices such as cover crops and no-till, that we can 
help draw down the carbon and store it in the soil.
    The current conservation delivery system is the gold 
standard of the world. Our hard-working NRCS field staff, along 
with conservation districts, are delivering these benefits not 
only to farmers, but to the rural communities. I also believe 
that the private-sector can play a role in addressing the 
climate crisis. Companies like Land O'Lakes are leading in 
conservation finance, converting methane into energy, and 
working on private carbon markets.
    Now, let me state for the record, I support private 
ecosystem markets as long as those markets are focused on 
benefits to the producers. I do not think the government should 
be intervening in those markets, and I hope we can concentrate 
more on proven solutions. I hope all of us can agree that a 
much greater expansion and more rapid deployment of high-
quality broadband connectivity is essential in this regard. It 
is essential for our rural communities, and it is essential to 
data-driven climate solutions. Broadband isn't just needed in 
our homes; it is especially needed on our farms as well. 
Agriculture is science. It is technology. It is innovation. The 
demands of a 21st century farm economy and economically viable 
climate solutions depends on reliable connectivity.
    Thanks to innovations in agriculture technologies, farmers 
are not the only conserving resources, they are doing so while 
producing more food, more fiber, and more feed. Productivity 
relative to resource use for agriculture is up a whopping 280 
percent in the United States since the 1940s, while total farm 
inputs are mostly unchanged during this time period.
    Now, I believe this is something that isn't talked about 
enough. U.S. producers are the shining star when it comes to 
resiliency and sustainability. U.S. producers are the answer to 
reducing global emissions, not the problem as so many activists 
would have you believe. However, without high-speed internet 
connectivity at both the farmhouse and the field, many of these 
new technologies that have helped create these efficiencies 
will never be realized to their fullest potential.
    Continuing to build on the conservation success of American 
farmers will reap additional emission benefits and increase 
U.S. farming's competitive advantage globally. The men and 
women who farm our lands are the original stewards of that 
land. The left will give them no credit for all of the 
advancements they have made in protecting our natural 
resources. The wrong approach with burdensome regulations or 
policies that dramatically increase costs will harm rural 
economics, while displacing U.S. production with that of less 
efficient, foreign producers leading to an increase in global 
greenhouse gas emissions.
    The question we have to ask ourselves is: who do we want 
supplying the world agriculture products? Is it the most 
efficient, low-emission producer that creates jobs in America, 
or the highest emitting sources that create jobs overseas? If 
you care about the American farmer, as well as addressing 
climate, the answer should be obvious.
    Again, Mr. Chairman, thank you so much for holding this 
hearing today. I know you believe, as I do, that our farmers 
and ranchers can be part of the solution to the climate issues.
    Thank you again to our witnesses, and I yield back.
    The Chairman. Well, thank you, Ranking Member Thompson.
    The chair would request that other Members submit their 
opening statements for the record so that we can move on and 
begin to hear from our wonderful panel.
    [The prepared statements of Mr. Costa and Ms. Pingree 
follow:]

Prepared Statement of Hon. Jim Costa, a Representative in Congress from 
                               California
    As Chairman of the Livestock and Foreign Agriculture Subcommittee, 
I am committed to ensuring that farmers and ranchers have access to 
processing and connections to markets for their products. In the 116th 
Congress, I worked to establish the new RAMP-UP grant program to assist 
existing facilities in making improvements to come under Federal 
inspection. I also supported the recent House-passed provisions to 
reduce overtime costs for small and very small Federal establishments. 
And, I look forward to continuing to work with my colleagues to address 
this important issue, but these improvements cannot come at the expense 
of food safety. Given some discussion today on expanding sales of 
uninspected meat, I would like to submit two letters,* from food safety 
groups and from groups representing farmers and ranchers, outlining 
concerns with legislative efforts that would undermine current Federal 
food safety standards for meat and poultry.
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    * Editor's note: the letters referred to are located on p. 329.
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                                 ______
                                 
    Prepared Statement of Hon. Chellie Pingree, a Representative in 
                          Congress from Maine
    I want to thank Chairman Scott and Ranking Member Thompson for 
holding a hearing on the important topic of climate change and the 
agriculture and forestry sectors. We know that climate change is 
impacting agriculture. In Maine, average temperatures have increased 
about 3 F since the beginning of the 20th century and the Northeast is 
warming faster than other regions of the country. All 16 counties in 
Maine were under a U.S. Department of Agriculture (USDA) Secretarial 
Disaster designation at some point in 2020 due to severe drought, which 
may have been exacerbated by climate change. This is a serious threat 
to our agriculture industry, which has an annual economic impact of 
$3.8 billion and supports more than 25,000 jobs.
    We also know that agriculture affects our climate. There is no 
doubt that the primary driver of the climate change we are experiencing 
is anthropogenic emissions of greenhouse gases like carbon dioxide, 
nitrous oxide, and methane, and there is no doubt that the agricultural 
sector plays a measurable role in emitting these greenhouse gases. 
While U.S. agriculture has made efficiency gains that have reduced 
emissions per unit over the last several decades, agriculture 
contributed 9.6 percent of total U.S. greenhouse gas emissions in 2019-
equivalent to 628.6 million metric tons of CO2.
    We need to do more to support farmers in adapting to, and 
mitigating their effect on, our changing climate. While the climate 
crisis poses a serious challenge for farmers, we can increase 
resilience, reduce greenhouse gas emissions, and sequester more carbon 
in the soil by providing these farmers with additional incentives and 
tools to shift to climate-smart practices, while ensuring they have the 
technical assistance necessary to successfully adopt them. I appreciate 
that there has been broad agreement on both sides of the aisle that 
science-based, farmer-driven, and voluntary policies offer the best 
path forward. These are the principles I used to develop a bill I plan 
to reintroduce in the coming weeks, the Agriculture Resilience Act.
    One of the themes of the hearing was the need for education: for 
farmers and for the Natural Resource Conservation Service (NRCS) 
professionals and extension agents that work with them. USDA's 
Northeast Regional Climate Hub is already helping Maine NRCS focus more 
on climate-smart practices through regionally specific, ``farm smart'' 
training. The Agriculture Resilience Act would build on these efforts 
by permanently authorizing and better resourcing the Climate Hubs. It 
would create a new technical assistance initiative devoting one percent 
of farm bill conservation funding to helping producers adopt practices 
that increase climate resilience and mitigate their emissions. Both of 
these policies were included in the policy recommendations of the Food 
and Agriculture Climate Alliance, an industry coalition that includes 
the American Farm Bureau Federation represented by Mr. Duvall. The bill 
would also support additional research, on-farm energy initiatives, 
opportunities to enhance farm viability and improve soil health, 
pasture-based livestock systems, and food waste reduction efforts, with 
the ultimate goal of making the U.S. agriculture sector achieve net 
zero emissions by 2040.
    There has also been discussion among my colleagues about the 
diversity of American agriculture and how climate solutions cannot be 
one-size-fits-all. We know this in Maine--we are a state characterized 
by small- and medium-sized diversified farms. The University of Maine 
has taken a comprehensive look at the mitigation potential of Maine's 
agriculture and forestry sectors and identified potential strategies 
that would be most effective for the state, including applying biochar, 
reducing tillage, and using more effective manure management. If Maine 
farmers collectively adopt these practices, the UMaine researchers 
estimate that the sector could mitigate up to 786,000 tons of 
CO2 equivalent per year in greenhouse gas emissions, or 
about double the sector's current emissions. This would come at the 
total cost of $26.3 million per year, or about 0.017 percent of the 
USDA's overall annual budget. I have included this report for the 
record with my statement.*
---------------------------------------------------------------------------
    * Editor's note: the report referred to is located on p. 333, and 
is available at: https://crsf.umaine.edu/wp-content/uploads/sites/214/
2020/09/UMaine-NCS-Interim-Report_1Sept
20.pdf.
---------------------------------------------------------------------------
    I look forward to working with my colleagues on the Agriculture 
Committee, our partners at USDA, and my fellow producers in Maine to 
make meaningful strides to mitigate climate change by helping farmers 
to be part of the solution.

    [The Chairman.] Once again, I would like to welcome all of 
our witnesses, and thank you for being here today for this 
historic and very, very critical hearing.
    First, we welcome Mr. Jim Cantore. Mr. Cantore is a senior 
meteorologist for The Weather Channel who has worked as a 
renowned forecaster for more than 30 years, forecasting the 
nation's weather day-to-day and reporting live from the field 
on severe weather events. He has also helped produce 
documentaries on meteorology, broadcasting in historic storms. 
Mr. Cantore holds an American Meteorological Society Television 
Seal of Approval and received an Emmy award in 2019 for his 
work on The Weather Channel's immersive mix reality 
storytelling.
    Our next witness is Ms. Pamela Knox. Ms. Knox is the 
Director of the University of Georgia's Weather Network, as 
well as an agricultural climate--excuse me, I am convinced I 
can get that last word right--Agricultural Climatologist for 
the University of Georgia in the Department of Crop and Soil 
Science. She provides outreach and education on climate and its 
effect on crops and livestock in the southern United States. 
Ms. Knox also serves on the Technical Advisory Boards of the 
Southeast Regional Climate Center, or at NOAA and the Southeast 
Regions Climate Hub at USDA.
    Our third witness today, who I am also so pleased to be 
able to invite and join us, is my good friend President Zippy 
Duvall. Zippy is President of the American Farm Bureau 
Federation. Mr. Duvall has served as President of Farm Bureau 
since 2016, and he is a third-generation farmer from Georgia. 
He owns a beef cow herd, raises broiler chickens, and grows 
hay. Prior to serving as the AFBF President, he was President 
of the Georgia Farm Bureau and served on Farm Bureau's Board of 
Directors. A gentleman I have had the privilege of working with 
for a number of years, even during my years in the Georgia 
State Senate.
    Next, we will hear from Mr. Gabe Brown. Mr. Brown operates 
Brown's Ranch with his wife, Shelly, and son, Paul. Brown's 
Ranch is a diversified 5,000 acre farm and ranch near Bismarck, 
North Dakota, with a variety of cash crops, multi-species cover 
crops, and livestock that utilize grazing and no-till cropping 
systems. He is also a partner in the agricultural consulting 
company named Understanding Ag.
    Our fifth and final witness today, we are pleased to 
welcome Mr. Michael Shellenberger. Mr. Shellenberger is the 
founder and President of Environmental Progress. He is an 
environmental journalist and the author of several books, 
including the recently published book, Apocalypse Never. Mr. 
Shellenberger was the co-founder and President of the 
Breakthrough Institute.
    What a panel, and we are anxious to hear from you.
    We will now proceed with our hearing and the testimony. 
Each will have 5 minutes. The time should be visible to you on 
your screen, and will count down to zero, at which point, your 
time will have expired.
    Mr. Cantore, please begin now.

  STATEMENT OF JIM CANTORE, SENIOR METEOROLOGIST, THE WEATHER 
                      CHANNEL, ATLANTA, GA

    Mr. Cantore. Chairman Scott, Ranking Member Thompson, and 
distinguished Members of the Committee, good afternoon. I am 
Jim Cantore and I am a meteorologist for The Weather Channel 
television network. I have been a weather forecaster for almost 
35 years. I am here today on behalf of The Weather Channel to 
testify about the increasing impacts of climate change on the 
agricultural and rural communities of the United States, as 
well as the impact on the entire U.S. population.
    Over the past several decades, scientists from all over the 
world have been studying changes in the Earth's atmosphere and 
weather patterns. Recent weather observations are confirming 
what computer models and scientific theory conclude.
    First, climate is warming due to an increase in greenhouse 
gases, especially carbon dioxide in the atmosphere. Second, the 
changes are overwhelmingly caused by humans. Third, there is a 
definite link between increasingly extreme weather and the 
warming planet.
    Carbon dioxide in our atmosphere has been steadily 
increasing, and in response, so have the temperatures. Since 
1880, the average global temperature has been increasing at a 
rate of .14 F per decade. However, since 1981, the increase is 
more than twice that rate.
    These numbers may seem small, but much like our body 
temperature, the Earth's temperature is remarkably stable. 
Simply put, the planet has a fever, and it is getting worse. 
The statistics are alarming. The last 7 years have been the 
warmest on record. Ice sheets and glaciers worldwide are 
melting and draining water into the ocean, raising the sea 
level. In New York City, the ocean sits roughly 1 higher than 
when the Empire State Building was built in 1930. By the end of 
the century, the global average sea level will likely be over 
1 higher than it is today, but future pathways with high 
greenhouse gas emissions could raise those seas by over 3 by 
2100.
    Flooding will be a daily occurrence with each high tide 
along the Eastern seaboard and Gulf Coast. We already see this 
in our country on sunny days in places like Miami, Florida and 
Charleston, South Carolina. Extreme temperatures and prolonged 
drought are increasing the risk of water shortages and 
wildfires over the western U.S. Extreme rainfall events are on 
the rise, increasing the chances for more serious flash 
flooding, and the strongest hurricanes are getting stronger, 
and potentially slowing down.
    The costs are staggering. Billion-dollar disasters are on 
the rise, and we have a short video to take a look at one from 
last year that hit farmers particularly hard.
    [Video shown.] \2\
---------------------------------------------------------------------------
    \2\ Editor's note: the video is retained in Committee file.
---------------------------------------------------------------------------
    Mr. Cantore. Our Weather Channel viewers are the very 
people who climate change is affecting the most. They are our 
farmers, our first responders, our airline pilots, our 
truckers, our working-class families. While the phrase climate 
change has long been politicized in this country, these 
Americans are now facing this today in real time what people 
thought might be a 22nd century problem. They are seeing their 
crops being washed away in 500 year floods, their livestock 
killed in monstrous wildfires, and landfalling hurricanes.
    In conclusion, I used to question the roots of climate 
change theories. I, like many, doubted that climate change had 
its origins in human causes. But after covering severe weather 
for 3 decades, including more than 100 tropical systems, dozens 
of tornado outbreaks, and more floods than I can remember, I am 
here to tell you that climate change is real, and we are 
absolutely playing a role in this. Not every disaster is driven 
by climate change, but more and more, we are seeing things we 
have never seen before, and the link to climate change in many 
of these events is present.
    Our country is suffering. Just ask the folks in Texas. 
While these changes are alarming, there is still time. With the 
government's help, our farmers will be able to adapt to 
changing temperatures and can even mitigate future warming. But 
we must act now to make the tough choices that will not only 
improve the lives of future generations, but those of all 
generations living today and tomorrow. And for those farmers 
whose life work is to feed this country and sustain one of the 
most time-honored industries of our great nation, we have a 
responsibility to help.
    [The prepared statement of Mr. Cantore follows:]

 Prepared Statement of Jim Cantore, Senior Meteorologist, The Weather 
                          Channel, Atlanta, GA
    Chairman Scott, Ranking Member Thompson, and distinguished Members 
of the Committee. Good morning. I am Jim Cantore, and I am a 
meteorologist for The Weather Channel television network. I have been a 
weather forecaster for more nearly 35 years.
    As farmers and the entire agriculture industry are aware, weather 
is the inescapable and ever-changing environment in which we live. As 
our climate changes, weather is becoming more volatile. As we witnessed 
last week across Texas and several other states, no person, business, 
community or entire state can escape its extremes. Dangerous cold, snow 
and ice revealed infrastructure failures, tested the human will for 
survival and sadly cost dozens of Americans their lives.
    I am here today on behalf of The Weather Channel to testify about 
the increasing impacts of climate change on the agricultural and rural 
communities of the United States, as well as the impact on the entire 
U.S. population. Our job is to prepare Americans for these difficult 
times and help them navigate our changing Earth. Our responsibility as 
scientists is to follow the data. We are on the side of the American 
people, and it is up to us to explain the science in plain terms.
    Over the past several decades, scientists from all over the world 
have been studying changes in [E]arth's atmosphere and weather 
patterns. Recent observations are confirming what computer models and 
scientific theory conclude:

   Earth's climate is changing faster than at any point in the 
        history of modern civilization, primarily as a result of human 
        activities that emit greenhouse gases into the atmosphere.

   The impacts are already being felt in the United States and 
        are projected to intensify in the future--Americans will be 
        dealing with even more extreme and costly weather in every 
        season.

   The severity of these impacts will depend largely on actions 
        taken to reduce greenhouse gas emissions and to adapt to the 
        changes that will occur.

    Carbon dioxide in our atmosphere has been steadily increasing and 
in response, so have the temperatures. Since 1880 the average global 
temperature has been increasing at a rate of 0.14 F per decade. 
However, since 1981 the increase is more than twice that rate (0.32 
F). These numbers may seem small, but much like our body temperature, 
earth's temperature is remarkably stable . . . simply put, the planet 
has a fever and it is getting worse. The statistics are alarming:

   The last 7 years have been the warmest on record.

   Ice sheets and glaciers worldwide are melting and draining 
        water into the ocean, raising the sea level. In New York City, 
        the ocean is roughly 1 higher than when the Empire State 
        Building was built in 1930.

   By the end of this century, the global mean sea level will 
        likely be over a foot higher than today, but if we continue to 
        emit high levels of greenhouse gases, it could rise over 3 by 
        2100. Flooding will be a frequent occurrence with each high 
        tide along the eastern seaboard and Gulf Coast.

   Extreme temperatures and prolonged drought are increasing 
        the risk of water shortages and wildfires over the western U.S.

   Extreme rainfall events are on the rise, increasing the 
        chances for more serious flash flooding.

   And the strongest hurricanes are getting stronger.

    I have seen these changes firsthand. Over my nearly 35 year career 
as a meteorologist at The Weather Channel, I have observed storms 
growing stronger, producing more precipitation and bringing destruction 
to areas that have never seen similar damage.
    On October 8, 2016, I was covering Hurricane Matthew in Lumberton, 
North Carolina. My team and I came upon a motel where people had 
evacuated from the North Carolina and South Carolina coasts, as their 
local officials had instructed them. They came to Lumberton, thinking 
that this far inland--about 80 miles--they would be safe from the storm 
surge they were facing on the coastline. But what they encountered in 
Lumberton was excessive inland rainfall, over 18" in the region. We had 
to help evacuate these people in boats to higher ground--due to this 
historic flood event. Again, Hurricane Matthew's inland devastation was 
evidence that many of these tropical systems are stronger, wetter and 
slower moving than we have seen in the past. This storm also left 
partially harvested cotton, soybean, and sweet potato farms across 
North Carolina submerged. Farmers who lost pigs and chickens barely 
recovered before Hurricane Florence hit in 2018. Devastating rainfall 
is a trend we are seeing with a likely climate link.
    Also, in 2018, Hurricane Michael rapidly intensified to a category 
5 upon landfall along the Gulf Coast. The hurricane-force winds lasted 
so long, and moved so far inland, the storm devastated the pecan crop 
in Georgia. That was the third year in a row the Georgia pecan crop had 
taken a hit from hurricanes--and Michael was the coup de grace. Even on 
the west side--the weak side--of the storm, across the Florida 
panhandle, there were massive timber losses--trees, snapped like 
twigs--where you could smell the pine in the air for miles. The crop 
losses in Georgia and Florida totaled more than $3 billion. Relief to 
farmers was slow, and so is the regeneration of this region's crops
    Our Weather Channel viewers are the very people whom climate change 
is affecting the most. They are our farmers, our first responders, our 
airline pilots, our truckers, our working-class families. While the 
phrase ``climate change'' has long been politicized in this country, 
these Americans are now facing today, in real time, what people thought 
might be a 22nd century problem. They are seeing their crops being 
washed away in 500 year floods; their livestock killed in monstrous 
wildfires; their children being diagnosed with increasing respiratory 
illnesses due to a more hostile atmosphere.
    In 2020 there were 22 weather/climate disaster events with losses 
exceeding $1 billion each to affect the United States. These events 
have been increasing over the last 40 years. The 1980-2020 annual 
average is seven events; the annual average for the most recent 5 years 
(2016-2020) is 16.
    One of the most memorable of these events occurred last August when 
we saw one of the costliest severe thunderstorms in U.S. history damage 
over 700 miles of the upper Midwest--much of it farmland.
    My colleague Dave Malkoff was on the ground in Benton County, Iowa 
as farmer Ben Olson was picking up the pieces of his destroyed corn 
crop. Early estimates from the Iowa Corn Growers Association put the 
loss at around 10 million acres, which is well over a billion bushels 
of corn. With a bushel selling for about $3 and 40 each, that's more 
than a $3 billion loss. And Mr. Olson and his neighbors are left with 
farms of rotting corn.
    And whether or not your districts are directly affected by a 
disaster, you and your constituents are helping foot the bill. Billion-
dollar natural disasters are on the rise in many parts of the country, 
climate change is playing a role. As policymakers, you are well aware 
of not only the cost of American lives and livelihoods, but also the 
detrimental impact these billion-dollar disasters have on our Federal 
and state budgets.
    In Conclusion: I used to question the roots of climate change 
theories. I, like many, doubted that climate change has its origins in 
human causes. But after covering severe weather for 3 decades, 
including more than 100 tropical systems, dozens of tornado outbreaks, 
and more floods than I can remember, I am here to tell you that climate 
change is real and we are absolutely playing a role in this. Not every 
disaster is driven by climate change. But more and more we are seeing 
things we have never seen before, and a link to climate change in many 
of these events. And our country is suffering; just ask the folks in 
Texas. While these changes are alarming, there is still time. With the 
government's help, our farmers will be able to adapt to changing 
temperatures and can even mitigate future warming. But we must act now 
to make the tough choices that will not only improve the lives of 
future generations but those of all generations living today and 
tomorrow. And for those farmers whose life's work it is to feed this 
country and sustain one of the most time-honored industries of our 
great nation, we have a responsibility to help.

    The Chairman. Thank you. Thank you so very much for that 
profound and extraordinarily excellent presentation. You 
grabbed it where it needed to be grabbed, Mr. Cantore. I hope I 
got that right. I will keep working on it as we move.
    Next, we will now hear from Professor Knox. Please begin 
now.

 STATEMENT OF PAMELA N. KNOX, DIRECTOR, UNIVERSITY OF GEORGIA 
                 WEATHER NETWORK; AGRICULTURAL 
      CLIMATOLOGIST, UGA COOPERATIVE EXTENSION, ATHENS, GA

    Ms. Knox. Good afternoon, everyone. My name is Pam Knox, 
and it is an honor to speak to you all today. I thank Chairman 
Scott and Ranking Member Thompson, and all the Members of the 
Committee who are allowing me the chance to share my expertise.
    I am an Agricultural Climatologist, and an extension 
specialist in the College of Agricultural and Environmental 
Sciences at the University of Georgia. I am also the Director 
of the UGA Weather Network, which is a mesonet of 87 stations 
across the state that provides agricultural information to 
farmers and foresters in Georgia. You can see a picture of one 
of my stations behind me.
    Before I took my current job, I worked as a USDA funded 
research scientist studying climate impacts on the Southeast, 
and livestock impacts of climate change across the U.S. I am 
also a former state climatologist for Georgia and Wisconsin.
    What I want to talk about today is the importance of 
climate to agriculture and forestry. We know agriculture and 
forestry are highly affected by swings in weather and climate. 
Year-to-year changes in temperature and precipitation can be 
hard for farmers to deal with and making a bad choice of crops 
or management practices can be costly. In addition to the 
natural variations of the climate, the U.S. is also getting 
warmer, as Jim mentioned, due to increases in carbon dioxide, 
methane, and other greenhouse gases. Average temperatures in 
the U.S. have gone up by almost 2 F in the last 60 years. 
Higher temperatures mean longer growing seasons, more heat 
stress on livestock and outdoor workers, more time for diseases 
and pests to threaten crops, and a more unpredictable water 
cycle. It also means more extreme events such as heatwaves, 
droughts, and floods that put farmers and foresters at risk by 
destroying crops and forests, and flooding fields and pastures.
    Agriculture and forestry are being affected by climate, but 
they are also contributing to warming temperatures by adding 
greenhouse gases to the atmosphere and changing the surface of 
the land. Livestock production releases methane into the 
atmosphere. Using too much fertilizer adds nitrous oxide into 
the air, and also pollutes streams and lakes. Cutting down on 
forests and draining wetlands for crops in urban areas releases 
carbon dioxide and methane. On top of this, 30 to 40 percent of 
all the food produced is never used. This means that the fuel, 
water, and fertilizer that is used to produce it is wasted, and 
more greenhouse gases are produced as that food waste is dumped 
into landfills, and tractors and water pumps are run for no 
good reason.
    Fortunately, agriculture and forestry can be powerful 
helpers in fighting climate change, too. Planting cover crops 
can prevent greenhouse gas emissions tied to fertilizers in 
irrigation by keeping water, carbon, and nutrients in the 
ground in the first place. Growing more trees and improving 
cropland productivity can pull carbon dioxide from the air. 
Many of these choices also help the farmers' bottom line by 
reducing the cost of fuel, agricultural chemicals, and the 
labor needed to apply them. A lot of these solutions don't need 
to be costly, either. They can be a real benefit to lower 
income and Black farmers with limited resources when you use 
these simpler solutions.
    Climate change is already here, and farmers, ranchers, and 
foresters are already learning to adapt to the new conditions. 
Some farmers are taking advantage of the longer growing seasons 
by double-cropping, or growing new crops like satsumas and 
olives in Georgia, for example. Livestock producers are using 
shade structures or cooling barns to protect their animals from 
heat stress. Foresters are testing out new varieties of pine 
and other commercial tree varieties that can survive and thrive 
in the future. Many producers are also using smart irrigation 
techniques, and other climate-smart management practices to use 
water efficiently, while protecting and improving the soils.
    But not all farmers know how to use these methods or can 
afford to follow them. So, information and training on best 
practices need to be available for them to make the best use of 
their land. Agencies like USDA, NOAA, NASA, and others have a 
long history of providing science-based, region-specific 
information and technologies to farmers, ranchers, and 
foresters across the country to help them monitor local climate 
and prepare for and respond to extreme weather and changes in 
climate. Other programs provide financial support for 
scientists studying the problems of extreme weather and climate 
change.
    Knowledge, technology, and funding will all be needed to 
make a difference in fighting climate change.
    In closing, while farms, ranches, and forests are all 
contributing to the increasing greenhouse gases in the 
atmosphere, and the rising temperatures that they produce, they 
also have the potential to help the U.S. reduce global warming 
by reducing emissions as well as absorbing gases from the 
environment. USDA and other agencies should be encouraged to 
work with farmers and scientists to find the best, most cost-
effective ways to do this.
    Thank you all for your attention, and I look forward to the 
discussion on this and hearing your comments.
    [The prepared statement of Ms. Knox follows:]

 Prepared Statement of Pamela N. Knox, Director, University of Georgia 
     Weather Network; Agricultural Climatologist, UGA Cooperative 
                         Extension, Athens, GA
Key Points
   Climate change is impacting agriculture and forestry by 
        raising temperatures, which: affect the length of the growing 
        season, degree days and chill hours; cause heat stress 
        affecting livestock and outdoor workers; enhance 
        evapotranspiration; and increase the likelihood of extreme 
        events like floods and droughts, all of which have negative 
        consequences on farm production.

   Agricultural and forest-based practices are affecting 
        climate change by adding greenhouse gases to the atmosphere and 
        altering the soil and land used for growing crops and 
        livestock, adding to the rise in temperatures through release 
        of methane and other greenhouse gases.

   Producers can reduce their emissions of greenhouse gases by 
        using climate-smart agricultural practices such as using more 
        cover crops and precision irrigation and by reducing food waste 
        and overuse of fertilizers and other agricultural chemicals, 
        which will help slow warming.

   Producers are already adapting to changes in climate by 
        adding cover crops, changing crop and tree varieties, and 
        adding new crops to their farms as well as adding cooling 
        structures and irrigation; these actions can make their farms 
        more resilient to changing climate and extreme weather.

   Farmers can benefit economically from conserving water, 
        fuel, and labor now while they are helping to reduce climate 
        change by managing their land and animals carefully.

   As farming and forestry become more technologically 
        advanced, new management tools will require access to more and 
        better local data to help producers make smart choices about 
        how they manage their farms and forests for health, safety, and 
        profit.
Introduction
    I would like to thank Chairman Scott and the other Members of the 
House Agriculture Committee for the opportunity to testify at this 
hearing to explore the relationship between agriculture and forestry 
and climate change. It is an honor and privilege to be with you today. 
My name is Pamela Knox, and I am a Public Service Associate with 
Cooperative Extension at the University of Georgia. I am currently the 
Director of the University of Georgia Weather Network and an Extension 
Specialist in agricultural climatology. I have worked on projects 
specifically related to agriculture, forestry, and climate change for 
the last decade. Prior to my current position, I was a research 
scientist funded by the U.S. Department of Agriculture (USDA) to study 
the impacts of climate variability and change on crop production in the 
Southeast and on livestock production across the United States. I also 
worked with the USDA Southeast Regional Climate Hub to identify how 
climate variability and change affect management decisions and day-to-
day activities on working lands across the region. I am currently a co-
Principal Investigator on two projects related to identifying the rapid 
onset and expansion of drought using soil moisture monitoring; one is 
funded by USDA and the other by NOAA. I am a previous President of the 
American Association of State Climatologists and have served as State 
Climatologist in Wisconsin and as Assistant State Climatologist in 
Georgia. I am also a Certified Consulting Meteorologist and have served 
as the Chair of the American Meteorological Society's Board on 
Certified Consulting Meteorologists as well as their Board of 
Professional Continuing Education and on their Standing Committee on 
Applied Climatology. My testimony today is my opinion, based upon my 
background and experience in studying agriculture and climate.
Overview
    According to the Bible and other ancient texts, agriculture is one 
of the earliest signs of civilization. Agriculture and forestry provide 
us with the food we eat, fiber we use to make clothing, and building 
materials and fuel that we use to provide shelter and keep us warm. In 
the United States in 2019, agriculture contributed over $1.1 trillion 
to the GDP, a 5.2 percent share of the economy.\1\ In addition, 
agriculture provided 10.9 percent of total U.S. employment.
---------------------------------------------------------------------------
    \1\ https://www.ers.usda.gov/data-products/ag-and-food-statistics-
charting-the-essentials/ag-and-food-sectors-and-the-economy/.
---------------------------------------------------------------------------
    Of all the sectors of the U.S. and the world economy, agriculture 
is arguably the one most affected by swings in weather and climate. 
Natural cycles of climate variability in the past have led to changes 
in agricultural activity as temperatures have risen and fallen and rain 
has come and gone. In periods when the local climate is favorable, 
those communities have expanded. Where drought, frosts, and extreme 
heat have occurred, agriculture has contracted and sometimes failed, 
leading to famine and migration as the citizens moved elsewhere or died 
out. Agriculture has also affected the communities around it by 
changing the nature of the land cover from forests to bare fields, 
affecting the local energy balance, temperature, and water cycle. In 
areas where agriculture expanded beyond the capacity of the local 
climate to sustain it, the land lost its ability to provide for those 
who lived there.
    Agriculture has also benefited from the rise of the Industrial 
Revolution, which provided agricultural producers with the mechanical 
ability to farm larger acreage, reduce the impacts of pests and 
diseases, and increase yield through the use of fertilizers and other 
agricultural chemicals. This has allowed us to feed a growing 
population. These benefits did not come without costs, however, since 
use of mechanical equipment requires fuel and factory production. 
Agricultural chemicals, when used improperly, have hurt natural 
ecosystems and contributed to the growth of toxic algae and diseases in 
water downstream. The cost of using this modern equipment has also put 
economic strain on lower-income and minority farmers who often have 
difficulty getting access to the most recent technology and information 
needed to maximize their potential yields. Clearing of land has reduced 
forest cover in some areas and released carbon dioxide and other 
greenhouse gases into the atmosphere, resulting in changes to the 
[E]arth's energy balance.
    Since 1895, annual average temperature in the United States has 
changed quite a bit from year to year (Figure 1), making planning for 
farmers difficult since what happened last year is probably not what 
they will experience this year. The annual average temperature has also 
changed on longer time scales due the influence of both natural cycles 
and human contributions to the global energy balance. Natural cycles 
include both shorter-term cycles such as the El Nino Southern 
Oscillation (ENSO) related to ocean temperatures in the eastern Pacific 
Ocean, and longer-term cycles in the global atmosphere and ocean. Those 
natural cycles occur on top of an upward trend that has been linked in 
numerous studies to increasing greenhouse gases in the atmosphere, 
which act as a blanket that holds the [E]arth's heat near
Figure 1. Contiguous United States Annual Average Temperature from 
        1895-2020 \2\
---------------------------------------------------------------------------
    \2\ NOAA National Centers for Environmental information, Climate at 
a Glance: National Time Series, published February 2021, retrieved on 
February 10, 2021 from https://www.ncdc.noaa.gov/cag/.


the surface instead of allowing it to escape to space. In the 57 year 
average lifetime of a farmer in the United States,\3\ the average 
temperature has risen by approximately 2 F. Overnight low temperatures 
have increased more than daytime high temperatures,\4\ which may be due 
to increases in humidity over time or to differences between the 
structures of daytime and nighttime atmospheric layers near the 
ground.\5\ This is important for agriculture because warmer nights hurt 
early-morning workers and prevent steers from gaining weight due to 24-
hour warmth.\6\
---------------------------------------------------------------------------
    \3\ 2017 Census of Agriculture, USDA National Agricultural 
Statistics Service.
    \4\ https://science2017.globalchange.gov/chapter/6/.
    \5\ https://phys.org/news/2016-03-nights-warmer-faster-days.html.
    \6\ https://www.climate.gov/news-features/blogs/beyond-data/
climate-change-rule-thumb-cold-things-warming-faster-warm-things.
---------------------------------------------------------------------------
    The annual average precipitation of the contiguous United States 
has also increased during that farmer's lifetime (Figure 2). As 
temperatures rise, the atmosphere can hold more water vapor than 
before. The result: as the water cycle has strengthened, both humidity 
and temperature have increased. That has not eliminated the year-to-
year swings that occur naturally due to ENSO and other internal cycles 
in the global climate system, so farmers still need to be able to 
respond to the short-term changes in rainfall, including droughts and 
floods, as well as plan for long-term changes that the warmer climate 
will bring. Precipitation is also becoming more variable, with more 
rain on the wettest days and longer dry spells between rainstorms.\7\
---------------------------------------------------------------------------
    \7\ https://www.epa.gov/climate-indicators/climate-change-
indicators-heavy-precipitation.
---------------------------------------------------------------------------
Figure 2. Contiguous United States Annual Average Precipitation \8\
---------------------------------------------------------------------------
    \8\ NOAA National Centers for Environmental information, Climate at 
a Glance: National Time Series, published February 2021, retrieved on 
February 10, 2021 from https://www.ncdc.noaa.gov/cag/.


    Changes in temperature and precipitation are also affecting the 
frequency and intensity of extreme events, including heat waves, 
floods, droughts, and severe weather like hurricanes and derechos, such 
as the one that devastated parts of Iowa last August. Floods have 
become more frequent and damaging due to a more active water cycle and 
increases in vulnerable infrastructure. This infrastructure was built 
to design standards for the past climate, which may not reflect what we 
are seeing now or will occur in the future. Droughts have become more 
frequent and often start and grow more quickly than in the past due to 
warmer temperatures and longer dry spells between rain events. We call 
these quickly developing droughts ``flash droughts,'' an area I study 
in my work. These droughts have a special impact on agriculture because 
crops and forage need regular amounts of water to grow and thrive, and 
if they do not get it, they can lose health and potential yields very 
quickly.
    Hurricanes and tropical storms so far do not seem to be increasing 
in number overall (although there is a lot of year-to-year variability 
based on natural cycles). However, recent research has shown that 
hurricanes are moving more slowly over land than they have in the past 
and are intensifying more rapidly just before they make landfall, which 
increases the damage they can do to coastal areas and crops that lie 
along the path of the storms after they come onshore.\9\ Extreme wind 
events such as tornadoes and derechos also do not appear to be 
increasing in number,\10\ although they may cause more damage than in 
previous years due to increases in shade trees and vulnerable 
infrastructure.\11\
---------------------------------------------------------------------------
    \9\ https://www.gfdl.noaa.gov/global-warming-and-hurricanes/.
    \10\ https://blogs.ei.columbia.edu/2016/12/01/increasing-tornado-
outbreaks-is-climate-change-responsible/.
    \11\ https://www.spc.noaa.gov/misc/AbtDerechos/derechofacts.htm.
---------------------------------------------------------------------------
    A warmer climate multiplies the risk from these events in the 
future by expanding the peak season for extreme events and expanding 
the area where they can occur toward the north. Winter storms might be 
expected to be less likely due to warmer temperatures, but the increase 
in the strength of the water cycle could make them produce more snow or 
ice, causing problems for farmers worried about the transportation of 
milk from farms to dairies and cutting off electricity needed for 
milking or power. Even if the frequency of the storms does not change, 
the increased use of sophisticated technology could make them more 
vulnerable to extreme weather in the future. Recent events such as the 
cold outbreak in the central United States last week have shown us that 
we are not even able to respond adequately to weather and climate 
extremes similar to ones we know have happened in the past; responding 
to the more variable and more extreme weather that we expect to see in 
the future as shown by climate models will be even more costly, 
disruptive, and challenging.
How Climate Change is Impacting Agriculture and Forestry
    Changes that we are seeing in our climate now are affecting 
agriculture and forestry in many ways. Rising temperatures are leading 
to warmer days and even warmer nights, which reduce heating costs in 
winter but increase cooling costs in summer. It also increases heat 
stress on both livestock and outdoor workers who are exposed to those 
high temperatures. Warmer overnight temperatures also harm some crops 
such as corn. The higher temperatures also lead to longer growing 
seasons, which Knox and Griffin (2014) estimated at roughly a 1 week 
increase in the growing season for every 1 F rise in temperature.\12\ 
The longer growing seasons provide opportunities for growing new crops 
and double-cropping but also lead to longer seasons for pests and 
diseases that affect the crops, forests, and animals. Warmer 
temperatures are also shifting climate zones to the north, changing the 
mix of crops and tree species that can be grown in any area or what 
times of year they can be grown successfully. The exact amount of 
temperature change that will occur cannot be predicted because there 
are so many unknowns to consider, including what choices humans make 
about greenhouse gas emissions in the future, but a range of increases 
from roughly 4 to 9 F is projected to occur by 2100 by most climate 
models, depending on the scenario chosen.\13\ These changes will not be 
uniform across the globe; some areas may see greater temperature rises 
than others, but all areas will be affected.
---------------------------------------------------------------------------
    \12\ P. Knox and M. Griffin, Using Analog Methods to Illustrate 
Possible Climate Change for Agricultural Producers, https://
ams.confex.com/ams/94Annual/webprogram/Paper232055.html.
    \13\ National Climate Assessment, 2018, https://
nca2018.globalchange.gov/chapter/2/.
---------------------------------------------------------------------------
    More variations in the water cycle provide both positive and 
negative impacts on agriculture. Northern parts of the United States 
are benefiting from more rainfall and a longer growing season now 
versus early in the 20th century. Crops such as corn are expanding into 
areas that previously could grow only wheat, for example. But the 
increase in the heaviest rain is leading to more erosion and flooding, 
both of which hurt farmers who are concerned with soil health and 
transportation of products to market. In dry years, longer intervals 
between rain events puts extra stress on crops and forests, especially 
where the water-holding capacity of soils is low. In the western United 
States, warmer temperatures have caused more precipitation to fall as 
rain and less as snow, which significantly affects the availability of 
irrigation water for crops as well as city water supplies because there 
is less storage of water in mountain snowpacks. Droughts are also 
expected to become more frequent and longer in a warmer world because 
the higher temperatures increase evaporation from soil, streams, and 
lakes, and increase evapotranspiration from plants. Even if the total 
amount of precipitation does not change, more evapotranspiration will 
lead to higher water demands by crops and more evaporation from lakes 
and reservoirs will make water shortages more frequent. Increases in 
heat spells are also expected to lead to more rapid onset of droughts 
and more frequent flash droughts that primarily affect crops and 
increase the occurrence of forest fires in the western United States.
    The increase in carbon dioxide (CO2) in the atmosphere 
is expected to have some fertilization effect on plants, since they 
take in CO2 as they grow. However, that effect is limited by 
the plant's ability to use the CO2 and the availability of 
other required elements, including water and nutrients. Scientists have 
also noted that some weeds grow much more quickly in enhanced 
CO2 environments than crops do. That could lead to more 
competition between crops and weeds, resulting in an increased need for 
herbicides, so the benefits from increased carbon dioxide are limited.
    In recent years we have had many examples of the devastation that 
extreme weather can have on agriculture and forestry. Hurricane 
Florence (September 2018) caused tremendous damage to the coastal 
Carolinas, primarily due to flooding from rains of up to 36" in 
Elizabethtown, North Carolina.\14\ The widespread flooding due to the 
slow-moving storm caused tremendous damage to sweet potatoes and other 
crops in eastern North Carolina and also caused the deaths of 3.4 
million chickens and turkeys and 5,500 hogs. Hurricane Michael (October 
2018) intensified just before landfall, bringing devastating winds 
through an area stretching from the Florida Panhandle to the northeast 
through southern Georgia and on into the Carolinas and Virginia. It was 
still a hurricane as it passed through central Georgia on October 10, 
and the UGA Weather Station in Donalsonville in far southwestern 
Georgia reported a wind gust of 115 mph as the eyewall passed over the 
airport location. Losses to agriculture and forestry in Georgia and 
Florida were estimated at over $3.3 billion.\15\ The storm hit about a 
week before most cotton was expected to be harvested, completely 
shredding many fields; it also flattened pine plantations and pecan 
groves that had been in farm families for generations, leading to years 
of losses of income for those families as they tried to reestablish 
their groves by planting new trees. Storms like the 2020 Midwestern 
Derecho also show the vulnerability of agriculture and forestry to 
severe thunderstorms and extreme weather, although it has not yet been 
determined whether these storms will become more frequent in the 
future.\16\
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    \14\ S.R. Stewart and R. Berg, National Hurricane Center Tropical 
Cyclone Report on Hurricane Florence, May 30, 2019, https://
www.nhc.noaa.gov/data/tcr/AL062018_Florence.pdf.
    \15\ J.L. Beven, R. Berg, and A. Hagen, National Hurricane Center 
Tropical Cyclone Report on Hurricane Michael, May 17, 2019, https://
www.nhc.noaa.gov/data/tcr/AL142018_Michael.pdf.
    \16\ https://www.spc.noaa.gov/misc/AbtDerechos/
derechofacts.htm#climatechange.
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How Agriculture and Forestry Are Impacting Climate Change
    The growth of agriculture and forestry over time have resulted in 
many benefits to our citizens, including better access to food, fiber, 
and building materials. But agriculture and forestry have had negative 
impacts on our citizens and our climate as well. Food waste due to 
inefficient use of farm production and citizen consumption results in 
30-40 percent of food being thrown away in the United States,\17\ even 
though many lower-income families do not have adequate access to the 
food they need. This leads to increased emissions of methane from 
landfills where the food is dumped. It also wastes the fertilizer, 
fuel, and water that was used to produce that food in the first place 
and the time and energy of people that are involved in producing and 
transporting that food from farm to market. Using too much fertilizer 
also results in the release of nitrous oxide, another greenhouse gas, 
which further increases global temperatures.
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    \17\ https://www.usda.gov/foodlossandwaste/why.
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    Livestock production allows ranchers and farmers to raise high-
quality protein on land that often cannot be used for other economic 
activities. However, methane emissions from cattle produce 14 percent 
of greenhouse gas (GHG) emissions globally per year, although it is 
only four percent of all GHG emissions in the United States.\18\ A lot 
of agricultural production goes towards providing the feed these 
animals use, and that production also emits greenhouse gases through 
the use of diesel fuel, fertilizers, and changes in land use from 
wetlands to cultivated crops.
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    \18\ https://www.ucdavis.edu/food/news/making-cattle-more-
sustainable/.
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    Overuse of fertilizer, especially in areas with frequent heavy 
rains, causes problems with toxic water both locally, in rivers 
downstream from the fertilized fields, and in the Gulf of Mexico and 
ocean estuaries. This affects the livelihood of fishermen there by 
reducing the catch of commercial species as well as harming local 
ecosystems. It also reduces the health of the stream and estuary 
ecosystems and can lead to higher costs to treat the water for human 
and animal consumption and industrial uses.
    Overall, the inefficient use of water and fertilizer and waste of 
food leads to serious economic consequences for agricultural producers, 
since they are the ones who pay for the diesel fuel to run equipment 
and pumps, and the chemicals needed to fertilize their crops and 
protect from weeds, pests, and diseases. Methods to make farms more 
efficient are often costly and put an extra burden on lower-income and 
minority farmers who cannot afford the cost of the added enhancements, 
leading to reduced production and even less money coming in.
How Agriculture and Forestry Can Reduce Emission of Greenhouse Gases
    Agriculture and forestry have a large role to play in reducing the 
effects of greenhouse gases. The best way to reduce greenhouse gases in 
the atmosphere is to prevent their emission in the first place. Then 
there is no need to remove them from the atmosphere later. In 2018, 
agriculture produced 9.9 percent of the U.S. emissions of greenhouse 
gases by economic sector.\19\ Worldwide, agricultural emissions account 
for 24 percent of all greenhouse gas emissions. These emissions come 
from numerous sources, including livestock production, release from 
agricultural soils, and rice production.
---------------------------------------------------------------------------
    \19\ https://www.epa.gov/ghgemissions/sources-greenhouse-gas-
emissions.
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    There are many ways that agriculture and forestry can help reduce 
the output of greenhouse gases. One of the biggest potential new ways 
to reduce emission of these gases is through reduction of food waste 
and packaging, which reduces methane emission from landfills where the 
unused food is buried and also reduces the amount of fuel, fertilizer, 
and transportation costs used to produce the food that is not used. It 
also reduces the amount of land that needs to be cleared for new crops. 
Improved diets for livestock and anaerobic digesters to recover methane 
from animal waste can reduce the amount of methane emitted. Using soil-
preserving methods such as growing cover crops helps keep carbon, 
nutrients, and water in the soil, reducing the need for fertilizers and 
running diesel-powered irrigation pumps. Making production more 
efficient by using tools like smart irrigation and better management of 
nitrate fertilizers also reduces the emission of greenhouse gases. The 
use of solar- and wind-powered pumps, where feasible, can also help cut 
the costs of fuel. Using new methods of cultivating rice using less 
water-intensive methods may also help to decrease methane emissions. 
Changing diets to eat lower on the food chain can also help reduce 
emissions.
    Farming and forestry can also help by removing carbon dioxide and 
other greenhouse gases from the atmosphere. Growing forests and 
improving cropland productivity both pull carbon dioxide from the air 
as ``carbon sinks.'' Many of the methods that reduce emission of these 
gases also help make the land better at removing carbon dioxide. For 
example, using no-till methods of farming keeps more water and 
nutrients in the soil and increases the health of the soil and of the 
plants in those fields, allowing them to suck up more carbon dioxide. 
Protection of existing forests and planting of new trees can also help 
to remove carbon dioxide from the atmosphere and cool the local 
climate. These practices also have other benefits such as protection of 
biodiversity, erosion control, and ecotourism, all of which can also 
benefit farmers.
    Many of these solutions can be implemented now and many farmers are 
already doing so. For example, the number of cover crop acres in the 
United States increased by 5 million acres from 2012 to 2017, according 
to the 2017 Census of Agriculture.\20\ There is also ongoing research 
funded by USDA and other agencies into how to make these practices even 
better and easier for producers to implement. Because there are so many 
different types of agricultural production, there is no ``one size fits 
all'' solution. Many of these newer methods of production will result 
in economic savings for the producers immediately without large capital 
outlays. This is particularly important for lower-income and minority 
farmers and will be valuable to producers regardless of how the climate 
changes because the newer methods reduce the use of costly fertilizers, 
fuel for field work and irrigation, and other expensive inputs.
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    \20\ https://www.farmprogress.com/cover-crops/census-finds-cover-
crop-acreage-increases-50-nationwide.
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How Agriculture and Forestry Can and Are Adapting to Changing Climate
    Since the climate is already changing and will continue to change 
for the foreseeable future based on greenhouse gases that have already 
entered the atmosphere or will be emitted in the future, farmers will 
also have to adapt to warmer temperatures, longer growing seasons, and 
more variable rainfall. In fact, many farmers have already started to 
take advantage of these changes. A longer growing season can lead to 
the enhanced ability to produce two crops instead of one (``double-
cropping''), or to choose different varieties with higher yield that 
take longer to grow. That allows producers to diversify and create 
multiple income streams from the different crops they grow. Farmers are 
also experimenting with new crops that expand their options for selling 
locally at premium prices. For example, in Georgia producers are now 
starting to grow satsuma mandarins in the southern parts of the state, 
and olive groves and pomegranates have also been introduced to expand 
market options. In the northern part of the United States, some areas 
that are seeing increased rainfall are now growing corn where it was 
not previously possible due to the dry conditions. Expansion of other 
crops towards the north may also occur where appropriate soils and 
rainfall permit them to grow. However, more research is needed on 
whether the changes in climate that are occurring are compatible with 
how those crops grow.
    Livestock producers are also adapting to a warmer climate by 
protecting their animals from heat stress using shade structures, or in 
some cases, keeping their dairy herds in air-cooled barns. New breeds 
like White Angus have been introduced to see if they can withstand high 
levels of heat stress better than current breeds. New hybrids of 
commercial crops and fruit such as peaches, which need a certain amount 
of cold weather to produce good yields, are being developed to grow in 
the new, warmer conditions. Foresters are also testing out different 
species of pine and other commercial varieties of trees to make sure 
that those forests will thrive under the climate conditions that are 
expected to occur as those trees mature. Many of these approaches 
require research to learn how to make the best choices, but farmers are 
already taking the lead on testing new varieties and new crops to 
determine their market values and growth patterns.
What USDA and other agencies are already doing to prepare for changes 
        in climate and extreme weather
    The USDA has a long history of providing science-based, region-
specific information and technologies to agricultural and natural 
resource managers across the United States, both alone and with other 
Federal and state agencies. This information helps land managers to 
make better choices based on scientific principles. The USDA also 
provides decision tools and guidance on how to use them so farmers from 
a wide range of backgrounds can use them effectively. In 2013, the USDA 
Climate Hubs were chartered to ``provide a link between research 
activities and practical, actionable information that producers can use 
to make climate-smart management decisions''.\21\ They are led by 
Agricultural Research Service [1] and Forest Service 
[2] senior Directors with contributions from many other 
programs including the Natural Resources Conservation 
Service,[3] Farm Service Agency,[4] Animal and 
Plant Health Inspection Service,[5] and the Risk Management 
Agency.[6] The hubs currently address how working lands can 
be managed to become more resilient to extreme weather including 
hurricanes, wildfires, floods, and droughts. For example, the Southeast 
Regional Climate Hub has produced a series of crop-specific hurricane 
preparedness and recovery guides \22\ that are being used to help 
producers plan for how to deal with hurricanes, which have severely 
impacted agriculture in the Southeast over the last 5 years. They also 
provide advice for what to do after a hurricane moves through the 
region. Other hubs provide information on dealing with drought and 
other types of extreme weather and climate that affect many different 
types of agricultural production. As an Extension specialist I use the 
information from all these sources to help producers make more informed 
choices about what crops to grow and how to manage them based on the 
current climate and what is predicted in the future.
---------------------------------------------------------------------------
    \21\ https://www.climatehubs.usda.gov/about-us.
    \[1]\ https://www.ars.usda.gov/.
    \[2]\ https://www.fs.fed.us/.
    \[3]\ https://www.nrcs.usda.gov/wps/portal/nrcs/site/national/home/
 
    \[4]\ https://www.fsa.usda.gov/.
    \[5]\ https://www.aphis.usda.gov/aphis/home/.
    \[6]\ https://www.rma.usda.gov/
    \22\ https://www.climatehubs.usda.gov/hubs/southeast/topic/
hurricane-preparation-and-recovery-southeast-us.
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    Other programs within USDA provide financial support for scientists 
who are looking for better solutions to problems related to extreme 
weather and climate change. I have benefited from several grants from 
the National Institute of Food and Agriculture (NIFA), including one to 
put together training materials for extension agents and producers on 
livestock and climate across the United States and another looking at 
the impacts of drought and a warming climate on crop production in the 
Southeast. Other initiatives have focused on forestry and tools to help 
foresters pick the tree varieties that will do best in the future 
climate. USDA is currently providing funds for a project that I am co-
Principal Investigator on that studies the impacts of ``flash'' 
drought. We are evaluating a variety of low-cost sensors that can be 
used by farmers in the Southeast to make water-smart decisions which 
will target efficient water use. This will also reduce fuel use and 
decrease the amount of fertilizer runoff into streams and, eventually, 
the ocean by using water wisely only when and where it is needed.
    In addition to USDA, there are many other Federal agencies working 
in the area of monitoring climate and preparing for and responding to 
weather extremes as well as preparing for future impacts. One of these 
groups is NASA; you will hear more about their activities from one of 
the other experts in this panel. The agency that I work with most often 
is the National Oceanic and Atmospheric Administration (NOAA), which 
provides information on real-time weather and climate conditions across 
the U.S. and the world. NOAA scientists and employees also work with 
many constituent groups on when to expect extreme weather conditions. 
They also work with emergency managers to prepare for extreme events as 
well as study extreme weather and climate events from the past to learn 
better ways to respond to them next time.
    In addition to Federal agencies, there are many state and local 
agencies and private organizations that are also working in the area of 
agriculture, forestry, and climate change. I am proud to be an 
Extension specialist at the University of Georgia. Surveys of farmers 
show that nearly half (47.8%) of farmers surveyed in a recent study 
found university Extension to be the most trustworthy source of climate 
change information.\23\ Extension agents serve a critical role in 
translating the science of climate variability and change into 
actionable decisions that local farmers can use to improve crop yields 
today and prepare for variations in climate in the future. We work with 
both academic and industry scientists and farmers, including those from 
both large and small farms, to identify developing critical conditions 
that may affect their crops and to help them plan for future impactful 
events.
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    \23\ Journal of Extension, https://www.joe.org/joe/2018june/a7.php.
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    Cooperative efforts between these groups have already produced 
important information about the relationship between agriculture and 
climate. The Fourth National Climate Assessment \24\ includes an entire 
chapter on Agriculture and Rural Communities that addresses many of the 
issues I have mentioned above and relates it to rural communities and 
the economies there, which are mainly driven by agriculture. USDA also 
released a new publication, Climate Indicators for Agriculture, which 
describes how changing climate is affecting agricultural indicators 
such as chill hours, growing degree days, extreme rainfall, and heat 
stress.\25\
---------------------------------------------------------------------------
    \24\ 4th National Climate Assessment, 2018, chapter on agriculture, 
https://nca2018.globalchange.gov/chapter/10/.
    \25\ Climate Indicators for Agriculture, https://www.usda.gov/
sites/default/files/documents/climate_indicators_for_agriculture.pdf.
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Recommendations to enhance efforts to assist agricultural producers 
        respond to climate change
    Based on the climate changes that have already occurred and will 
continue to change in the future, there are many ways that Congress can 
act to assist producers in both adapting to the ongoing changes and 
reducing the emission and concentration of greenhouse gases in the 
atmosphere. In general, Congress can encourage the use of research 
incentives to scientists to produce more targeted and applied ways of 
doing smart agriculture. This should not be done in a vacuum but should 
be done through collaboration with farmers using the expertise and 
assistance of Cooperative Extension and other groups that work at the 
intersection between science and production.
    To facilitate the use of smart agriculture, farmers should be 
equipped with improved access to resources like the internet so they 
can access tools and information that relate climate to agriculture and 
forestry. This will help farmers improve their farm and woodlot 
management choices and show them how to use the information 
effectively. Congress can also encourage access to needed agriculture-
specific data such as the agricultural weather networks (``mesonets'') 
that are already in place in some states and encourage their expansion 
to other agricultural areas that have fewer resources. This will help 
producers make effective decisions which will conserve resources and 
save money. This information should also be shared with other countries 
because improvements in agricultural production and better capture of 
carbon using water, fuel, and agricultural chemicals more efficiently 
will benefit the global climate system far more than just doing it in 
the United States alone.
    In conclusion, I would like to highlight the following four points:

  1.  The time to act is now.

        Reducing greenhouse gas emissions and responding to the 
            changing climate is not something that can wait until we 
            have perfect answers. We will never have perfect knowledge 
            since science is constantly making new discoveries and 
            farmers are innovating their own production methods at the 
            same time. If we wait, we will waste time while we put more 
            greenhouse gases into the air that will require removal. 
            The climate will get more extreme as a result of those 
            additional gases. It's better not to emit the greenhouse 
            gases in the first place. As our mothers reminded us, an 
            ounce of prevention is worth a pound of cure. The longer we 
            wait, the more unpredictable and extreme the climate is 
            likely to become. Technology is always changing, and we can 
            and must incorporate those changes into our management 
            plans in the future, but we can take concrete steps now 
            that will also save farmers money by reducing the costs of 
            production. You can think of this as a ship captain 
            responding to the sight of an iceberg ahead. If we respond 
            to it now, we can make smaller, less drastic changes that 
            will keep the ship safe, while if we wait, much more 
            wrenching changes will be needed the closer we get to the 
            iceberg in the future.

  2.  Economically, many farmers will benefit from these activities 
            regardless of how the climate is changing.

        Conserving water, fuel, and agricultural chemicals like 
            fertilizer and herbicides makes good financial sense for 
            farmers. Improving the health of the soils on farms, 
            rangelands, and in forests will provide additional benefits 
            to producers like better fertility and water-holding 
            capacity, making them more resilient to extreme climate 
            events like drought. It is especially true for producers 
            who own the land rather than renting it, because they 
            receive more tangible economic benefits from improving the 
            soil, since they may be able to use less water and 
            fertilizer over time. This is especially important for 
            producers who want to keep the farms in their families over 
            many generations, because they need to maintain the soil's 
            health over many years of production as well as minimize 
            production costs to keep more money on the farm. Climate-
            smart and sustainable agriculture also benefits local water 
            supplies, municipalities, and ecosystems because resources 
            are not being wasted or degraded.
        Note that not every solution will work for every producer. Farm 
            size, type of crop or crops, availability of money to use 
            on farm equipment, and expertise all vary widely across the 
            U.S. The use of irrigation to reduce vulnerability to 
            drought may help some commodity farmers but be too 
            expensive for small farmers unless simpler, lower-cost 
            alternatives are developed and encouraged. In some parts of 
            the country, like the Southeast, we usually have enough 
            water for crops compared to other parts of the United 
            States, but it sometimes needs to be supplemented to 
            provide a boost to crops during a hot, dry spell. This 
            water often only needs to be moved short distances to keep 
            the crops growing and requires the use of much smaller 
            infrastructure than the big irrigation projects out West 
            that move water long distances to get it to the crops that 
            need it. By working with scientists and producers to find 
            the best ways to keep their crops alive in a cost-effective 
            way, the farmers will be able to respond to the climate 
            variations we are seeing now as well as adapt to and become 
            more resilient to future climate change. This is especially 
            important because climate models have a harder time 
            predicting what the future precipitation patterns will be 
            than they do temperature patterns, and so flexibility in 
            how farmers adapt is particularly important. These low-
            cost, local solutions will especially benefit Black and 
            small-scale farmers because they will allow crops to 
            survive with lower costs than some bigger water projects, 
            although those also have a place in some parts of the 
            country.

  3.  Good management requires good data and useful tools.

        The best-managed farms use data to monitor their production and 
            determine where and when to apply water and agricultural 
            chemicals and decide when to harvest. Good data can also 
            tell them when their livestock are under stress and use 
            appropriate measures to keep them healthy. Tools such as 
            smart irrigation schedulers and precision agriculture can 
            cut costs and reduce the waste of fuel, water, and 
            fertilizer by allowing producers to apply the right amount 
            at the right time to maximize benefits to the crops without 
            overusing them. In the future, agriculture will become even 
            more technologically advanced. Use of machine learning and 
            artificial intelligence will require good input data, the 
            availability of computers and internet access, and access 
            to equipment that can take advantage of this knowledge.

        Traditional sources of weather data such as the National 
            Weather Service collect information that is useful for 
            farmers, but stations are widely separated and often do not 
            capture measurements that are agriculturally important such 
            as soil temperature, soil moisture and solar radiation. 
            This is where supplemental weather observations from 
            individual stations and networks of agricultural stations 
            in mesonets can be of tremendous importance. The House has 
            already recognized the importance of these mesonets in the 
            NOAA pilot program enacted under section 511 of the Water 
            Resources Development Act, which was included in the FY21 
            Appropriations package. Mesonets like the one that I manage 
            at the University of Georgia provided tremendous added 
            value to agricultural producers by increasing the density 
            of observations, especially in rural areas where 
            traditional weather observations are rare. They also 
            provide data that cannot be obtained from more traditional 
            sources. Production tools based on these data, such as 
            irrigation schedulers, warning systems for development of 
            critical pests and diseases, and trackers of crop 
            development stages can provide highly useful and important 
            information that farmers can use to minimize expenses and 
            maximize yield.
        To access weather and climate information and use tools 
            effectively, farmers must have access to both the weather 
            data and to the tools that use the data to make crop 
            predictions. That is especially difficult in rural areas 
            where access to the internet is limited, especially by low-
            income and Black farmers. To make maximum use of this 
            information, rural broadband access must be improved. New 
            agricultural tools need to be identified by scientists 
            working together with producers to make sure that they are 
            useful, reliable, and easy to use. Farmers must also learn 
            how to use these tools effectively so that they can apply 
            them to their management practices. Extension and the 
            climate hubs have an important role to play in making sure 
            this information is useful and is reaching the farmers who 
            need it. Use of the data along with the agricultural tools 
            that use them provide both short-term economic benefits to 
            farmers by reducing wasted money, fuel, and labor as well 
            as long-term benefits by reducing emission of greenhouse 
            gases.

  4.  Farmers and foresters must be an integral part of the process.

        No one knows better how to farm than the farmers themselves. 
            Innovation in farming has improved productivity 
            dramatically over time, and farmers will continue to work 
            to improve efficiency and manage crops better and more 
            economically. But farmers and foresters must work with 
            scientists to make sure they are not just doing what they 
            have always done before, if there is something better based 
            on science. They also need to know what the future weather 
            and climate risks to farming and forestry are so that they 
            manage their land appropriately. Scientists have the 
            expertise to test new innovations carefully and demonstrate 
            which ones are the most economical and beneficial. But 
            scientists need to work with producers to make sure that 
            the innovations are also practical and cost-effective and 
            address the issues that farmers have to deal with on a 
            daily basis.
        The USDA Climate Hubs along with other Federal climate centers 
            have an important role to play in both developing new tools 
            and information sources for producers and in telling the 
            farmers and foresters how to use these products 
            effectively. This can be done through publications, web 
            resources, and workshops, but they need to incorporate the 
            input of practicing farmers and foresters as well as 
            scientists. Extension also has an important role to play in 
            this process, since extension agents work in the fields 
            with farmers and see first-hand what problems the farmers 
            are facing and how available information is used as well as 
            what is missing. By serving as a liaison between the 
            scientists and the producers, extension agents bring 
            together academic and practical experience which will 
            produce the most effective solutions for agricultural 
            systems responding to both climate variations like drought 
            and extreme weather like hurricanes, forest fires, and 
            floods, both now and in the future. That way scientists and 
            farmers and foresters can work together to help solve the 
            problem of climate change in a way that benefits us all.

    Thank you again for the opportunity to provide you with this look 
at the relationship between agriculture and forestry and climate change 
in the United States. I look forward to hearing your comments and 
answering your questions on this topic.

    The Chairman. Thank you very much, Professor Knox.
    And now, Mr. Zippy Duvall, please start now.

  STATEMENT OF ZIPPY DUVALL, PRESIDENT, AMERICAN FARM BUREAU 
                  FEDERATION, WASHINGTON, D.C.

    Mr. Duvall. Well, good afternoon, Chairman Scott, Ranking 
Member Thompson, and all the Members of the Committee. I want 
to begin by thanking you for all the help you give our American 
farmers and ranchers over the last year and during this 
difficult time of the pandemic. It came on top of an already 
distressed farm economy, and we are all glad to see some 
positive turns.
    Keeping our farmers and ranchers in production is vital to 
our food security and our national security. As you know, 
farmers and ranchers work hard to keep food on our plates, 
while continuing to make great strides in sustainability, which 
brings us to the topic of today.
    American agriculture accounts for approximately ten percent 
of the total U.S. greenhouse gas emissions, far less than 
transportation, electricity generation, and other industry 
sectors. Total carbon sink efforts from forestland, grassland 
management, and management of cropland all offset approximately 
12 percent of the total U.S. emissions.
    To continue to make these gains in carbon sequestration, we 
need to increase investment in agricultural research. We need 
new technologies to help us capture more carbon in our soil. 
Farmers continue to produce more food, fiber, and energy more 
efficiently than ever before. Over the last two generations, we 
have tripled our production without using more resources from 
our land. In fact, we would have to add 100 million more acres 
than 1990 to match the same production of 2018.
    Our advancements in sustainability are due to adoption of 
technologies and our farmers terrific participation in 
voluntary, incentive-based conservation programs. United States 
farmers have enrolled more than 140 million acres in Federal 
conservation programs. That equals the total landmass of 
California and New York State together.
    Our farms and our land are our heritage. Every farmer I 
know wants to leave his land, air, and water and his ranch and 
farm business in better shape and better condition than he 
found it. To achieve that goal, Congress must protect 
agriculture from undue burdens and to respect farmers' and 
ranchers' ability to innovate and solve problems. We must work 
with Congress to explore new markets and new opportunities for 
agriculture.
    Farm Bureau's Grassroot Development Process supports 
market-based incentives for adopting practices and planting 
crops that keep carbon in our soil. We welcome the opportunity 
to participate in an emerging carbon market.
    To expand these opportunities, we convened a wide group of 
stakeholders to explore policy options that respect farmers and 
ranchers as partners, while also assuring that our rural 
communities can thrive. That effort became known as the Food 
and Agriculture Climate Alliance. It consists of organizations 
representing a cross section of farmers and ranchers, forest 
owners, food sectors, state governments, and environmental 
advocates. We are working together to develop and promote 
shared climate policy priorities. The Alliance is united under 
three principles that guide all 40 recommendations. First, we 
support voluntary market- and incentive-based policies. Second, 
we want to achieve science-based outcomes. And third, we want 
to promote the resilience and help our rural economy better 
adapt to climate changes.
    We hope the work of, and the recommendations of the 
Alliance ensure, farmers and ranchers will be respected and 
supported. We must ensure that public policy does not threaten 
the viability of our farms, and the long-term resilience of our 
rural communities. Americans have a new appreciation for the 
importance of agriculture after seeing empty shelves during the 
pandemic last year, and I am proud to assure that Americans in 
America that the commitment of the farmers and ranchers is 
unwavering, and we will still be farming. So, let's make sure 
that public policy doesn't stand in the way of our ability to 
continue to fulfill that commitment.
    Thank you, Mr. Chairman, for holding this hearing today. I 
look forward to the questions.
    [The prepared statement of Mr. Duvall follows:]

  Prepared Statement of Zippy Duvall, President, American Farm Bureau 
                      Federation, Washington, D.C.
    Mr. Chairman and Members of the Committee, my name is Zippy Duvall. 
I am a third-generation farmer and President of the American Farm 
Bureau Federation, and I am pleased to offer this testimony, on behalf 
of the American Farm Bureau Federation and Farm Bureau members across 
this country.
    America's farmers and ranchers play a leading role in promoting 
soil health, conserving water, enhancing wildlife, efficiently using 
nutrients, and caring for their animals. For decades they have embraced 
innovation thanks to investments in agricultural research and adopted 
climate-smart practices to improve productivity, enhance 
sustainability, and \1\ provide clean and renewable energy. In fact, 
the use of ethanol and biodiesel in 2018 reduced greenhouse gas 
emissions by an amount equivalent to taking 17 million cars off the 
road.
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    \1\ https://www.fb.org/land/fsf.
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    Livestock and crop production are the heart of American 
agriculture, providing the food we enjoy every day. The daily choices 
we make on our farm and ranches are driven by our commitment to 
sustainability. Farmers have embraced technologies that reduce 
emissions and increase efficiency, making U.S. agriculture a leader in 
sustainability. Building upon the strong foundation of voluntary 
stewardship investments and practices, including those in the farm 
bill, we look forward to working with policymakers to further advance 
successful sustainable practices in U.S. agriculture. Throughout this 
process, lawmakers must ensure that any governmental analysis 
characterizing U.S. crop and livestock systems reflects U.S. 
agriculture's leadership globally in sustainable farming practices.
    All told, agriculture accounts for approximately 10% of total U.S. 
greenhouse gas (GHG) emissions, far less than transportation, 
electricity generation, and industry sectors. Farmers continue to 
produce more with greater efficiency. In fact, U.S. agriculture would 
have needed nearly 100 million more acres in 1990 to match 2018 
production levels.\2\
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    \2\ https://www.fb.org/market-intel/ghg.
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    Carbon sequestration, achieved through the management of forestry, 
grasslands, wetlands, cropland and settlements contributed to GHG 
removals equivalent to 12% of total U.S. emissions. With increased 
investment in agricultural research we can develop the new frontier 
technologies to capture even more carbon in our croplands, our forests 
and our grasslands. We can definitely reduce our carbon footprint. With 
cutting-edge science, we may be able to achieve net zero emissions in 
some sectors of agriculture.
    U.S. farmers and ranchers have long been at the forefront of 
climate-smart farming, utilizing scientific solutions, technology, and 
innovations to raise crops and care for livestock. These efforts are 
designed to protect soil and water, efficiently manage manure, produce 
clean and renewable energy, capture carbon, and improve sustainability. 
Over two generations, we've been able to increase productivity by 287 
percent, while using the same resources. To say we're doing more with 
less is an understatement.
    Total carbon sink efforts from forestland management, land 
converted to forestry, grasslands, and wetland management more than 
offset agriculture's contribution to total emissions. However, many of 
agriculture's carbon sequestration efforts are not directly assigned to 
the agriculture sector. It is certain that if the carbon sequestration 
efforts of U.S. farmers and ranchers were assigned to agriculture, 
especially our forests, our contributions to GHG emissions would be 
lower. It is worth noting that U.S. farmers have enrolled more than 140 
million acres in Federal conservation programs--that's equal to the 
total land area of California and New York combined. Millions more 
acres are dedicated to non-Federal conservation programs.
    More productive livestock operations allow ranchers, pork 
producers, and dairy farmers to maintain their total contribution to 
GHG emissions at less than 3%. Innovation plays an important role, from 
methane digesters to advances in nutritional balance that lead to lower 
per-unit GHG emissions. In fact, we have seen a 25% reduction in per 
unit of GHG emission for our dairy industry, an 18% reduction in swine 
and close to a 10% drop for our beef cattle producers.
    U.S. farmers and ranchers contribute significantly fewer GHG 
emissions than their counterparts around the world. EPA data shows 
agriculture's global contribution to GHG emissions was 24% in 2010, 
more than double U.S. farmers' and ranchers' contributions to total 
U.S. emissions in 2019. This significant difference is largely driven 
by U.S. farmers' enthusiastic adoption of technology. American farmers 
and ranchers are pioneers of sustainability, and any policy debate 
should recognize their contributions, efficiency gains, and the 
considerable impact of their carbon sequestration efforts.
    With trade challenges and the impacts of the COVID-19 pandemic, 
America's farmers and ranchers are facing difficult headwinds. As we 
continue to work with Congress, we must explore new markets and 
opportunities for agriculture. We also recommend working with our 
international trade partners to make certain that national 
sustainability standards do not become trade barriers to our 
agricultural exports.
    At the American Farm Bureau, our policy is crafted by our 
grassroots members, hardworking farmers and ranchers, who recognize the 
value of a voluntary, market-based system of incentives for planting 
crops or adopting farming practices that keep carbon in the soil. That 
is why we welcome opportunities for farmers and ranchers to participate 
in emerging carbon markets.
    To further promote and expand these opportunities, the American 
Farm Bureau felt it was important to convene a wide group of 
stakeholders to further explore policy options for farmers, ranchers 
and rural communities. What came out of that effort is now known as the 
Food and Agriculture Climate Alliance which consists of organizations 
representing a cross-section of farmers, ranchers, forest owners, the 
food sector, state governments and environmental advocates that are 
working together to develop and promote shared climate policy 
priorities.
    The alliance united around three principles that guide our 40 
recommendations: Support voluntary, market- and incentive-based 
policies; advance science-based outcomes; promote resilience and help 
rural economies better adapt to changes in the climate. We hope the 
work and recommendations of the alliance ensure farmers and ranchers 
will be respected and supported as society pushes for more climate-
smart practices. Advocating for the right policies--voluntary, market- 
and incentive-based solutions--will allow us to build on our 
sustainability advances and recognize farmers as partners in this 
effort, while helping to prevent a move toward the punitive policies 
discussed a decade ago.
    Farm Bureau will continue to work to ensure that farm families 
maintain their ability to respond and adapt to climatic events and that 
public policies do not threaten the long-term resiliency of our rural 
communities. Congress must protect American agriculture and production 
practices from undue burden, and respect farmers' and ranchers' ability 
to innovate and solve problems.
    American farm families want to leave the land better than when it 
was first entrusted to our care. That is the story of my family's farm 
in Georgia and the story of millions of farms across this country. We 
want to protect the planet, feed and clothe people, and promote vibrant 
communities. Working with our partners, land-grant universities, 
policymakers, and the farmers and ranchers we represent Farm Bureau 
intends to continue finding solutions for the challenges of the future.
    Mr. Chairman, I commend you for convening this hearing and for all 
your hard work on behalf of agriculture across the country. I will be 
pleased to respond to questions.

    The Chairman. Well, thank you so much, President Duvall, 
for your excellent remarks there.
    Now, Committee, before we continue with introducing the 
witnesses today, and with the consent of my colleagues, I would 
like to share with you now a very brief clip from the 
documentary entitled, Kiss the Ground. My dear friend, 
Congresslady Jayapal of the State of Washington brought this 
film to my attention. I watched it on Netflix. I was very 
impressed with what they had to say, and I have invited them to 
show this very impressive film. It will introduce you to the 
possibilities of how we must balance our climate, replenish our 
water supplies, deal with the carbon, and most importantly, 
continue being the champions of feeding the world by taking 
care of our soil.
    Please start the clip now, would you?
    [Video shown.] \3\
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    \3\ Editor's note: the video is retained in Committee file.
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    The Chairman. Thank you very much for that, and what a very 
informative message. I would encourage as many of you to see 
the complete film, Kiss the Ground. It is now airing on 
Netflix.
    And now, we will return to hearing the testimony of the 
remaining two witnesses who are here with us today.
    Mr. Brown, you may begin your testimony now.

  STATEMENT OF GABE BROWN, CO-OWNER/OPERATOR, BROWN'S RANCH, 
                          BISMARCK, ND

    Mr. Brown. Thank you, Honorable Chairman Scott and Members 
of the Committee, for allowing me the opportunity to speak to 
you today.
    Since 1991, my family and I have owned and operated a ranch 
near Bismarck, North Dakota. As a farmer and rancher, I have 
been affected by the extreme variability in weather. Drought, 
flooding, extreme cold and heat: the change in our climate is 
affecting everyone and every farm. Agriculture is often 
vilified as being a major contributor to climate change, but 
you can help agriculture become a major part of the solution.
    First slide, please.
    [Slide.]
    Mr. Brown. On the left side of this picture are my soils 
today. On the right side are my neighbor's. These samples were 
taken only a few feet apart. The only difference is management, 
or as I like to call it, stewardship. In 1993, my soil organic 
matter levels were at 1.7 percent. Today, they are near seven 
percent. My neighbor's are at or below 1.7 percent. Today, my 
soils can infiltrate over 30" of water per hour, while my 
neighbor's can infiltrate less than \1/2\" per hour.
    So, how did farmers like me take large amounts of carbon 
out of the atmosphere and use it to regenerate our soils? The 
answer is we use six proven time-tested ecological principles. 
These principles will work on every farm in every one of your 
districts.
    Next slide, please.
    [Slide.]
    Mr. Brown. We start with context. We are not planting 
orchards in the desert. That is out of context. We are making 
our farms more resilient, but programs like crop insurance are 
not rewarding farmers for positive outcomes, and they are not 
based on environmental constraints. We are serious about not 
only reducing and eliminating tillage, but also significantly 
reducing all synthetic fertilizers and pesticides as they harm 
soil biology, our ecosystems, and our health.
    I am holding a pint jar of treated soybean seed. The 
neonicotinoids on this seed has the capability of killing 72 
million bees. This has to stop.
    Next slide.
    [Slide.]
    Mr. Brown. Allan Savory said it well when he said ``It's 
not drought that causes bare ground, it is bare ground that 
causes drought.'' We are keeping our soils covered with diverse 
living cover crops and grain crops, thus continuing to pump 
carbon into the soil, while protecting our soils from erosion, 
conserving moisture, and holding nitrates, phosphates, and 
other nutrients on our farms. We are prioritizing diversity. 
This Committee can help every farm, ranch, and CRP land to 
significantly increase the biodiversity of plants, insects, and 
soil biology.
    We realize the importance of grazing animals. Our richest, 
healthiest soils were formed in partnership with grazing 
ruminants. Proper use of grazing ruminants is one of the keys 
to carbon sequestration.
    Next slide, please.
    [Slide.]
    Mr. Brown. Down to 36" and beyond, adaptive regenerative 
grazing is seeing total carbon gains significantly higher than 
rotational or continuous grazing.
    Next slide.
    [Slide.]
    Mr. Brown. This is the Chihuahuan Desert. Many think that 
with only 6" to 8" of annual rainfall, it was always a desert.
    Next slide.
    [Slide.]
    Mr. Brown. The dark colored soil near the surface is 
carbon. This means it was recently a vast grassland. The 
erosion you see took only 60 years. You can drive through this 
desert, and then you open a gate to Alejandro Correo's ranch.
    Next slide.
    [Slide.]
    Mr. Brown. The difference is stewardship. He is using 
livestock to regenerate his soils and increase biomass. Where 
his neighbors need 300 acres to feed one cow per year, he only 
needs 30. As a result, regenerative farmers are substantially 
increasing the profitability of our farms and ranches, thus 
helping to revitalize our rural communities while producing 
food that is higher in nutrient density. We have done this 
while reducing our reliance on government programs. These 
programs should be a hand up or a reward for positive results.
    While more resources are needed, just increasing funding 
isn't going to solve it. We need to put that funding into what 
actually regenerates landscapes. We must make the adoption of 
regenerative ag available for all farmers from all backgrounds.
    From farmers to scientists to environmentalists to the 
government, we hear: ``I didn't know.'' Well, at one time, I 
didn't know either. We must educate, not only farmers and 
ranchers, but all society as to these concepts which are rooted 
in indigenous knowledge.
    It is not just about emission reductions. It is about our 
land's resilience and ability to function. Regenerating our 
soil ecosystem is the most cost-effective national investment 
we can make to mitigate climate change and heal society. The 
current system is broken. We need to change the way we see 
things. Regenerative agriculture is a win for all, and this 
Committee, Mr. Chairman, can help lead the way.
    Thank you for your time, and I look forward to your 
questions.
    [The prepared statement of Mr. Brown follows:]

  Prepared Statement of Gabe Brown, Co-Owner/Operator, Brown's Ranch, 
                              Bismarck, ND
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    Thank you, Honorable Chairman Scott, and Members of the Committee, 
for allowing me the opportunity to testify before you today.
    My name is Gabe Brown. I own and operate a 5,000 acre ranch near 
Bismarck, North Dakota with my wife, son and our family. We have farmed 
this land since 1991 and began by using conventional methods, but crop 
failures due to erratic weather, increased costs and rising debt led us 
to adopt a series of regenerative soil health practices. These 
practices have provided multiple benefits. Regenerative practices have 
made our farm profitable over the past 3 decades, and also increased 
our soil carbon over six-fold since we first started taking on-farm 
measurements in 1993.
    Today I make the case for wide-scale adoption of regenerative 
agriculture by sharing the essential opportunities afforded to me. 
Regenerative agriculture mitigates climate change while increasing 
resilience against current and future climatic uncertainty including 
flooding, fire and drought. It is essential to soil, plant, animal, 
human, community, and economic health. Regenerative agriculture does 
this by restoring our land and soil, the biology and the ecological 
cycles and processes which are foundational to human and planetary 
health and stability.
    As a farmer and rancher, I have been affected by the extreme 
variability in weather. 2020 was the second driest year ever recorded 
where I live and ranch in Burleigh County, North Dakota. Just this 
month the local weather station recorded the most consecutive days of 
^25. From drought to flooding, from extreme cold to extreme heat, the 
change in our climate is affecting everyone and everything, especially 
farmers.
    In 1997, I had the good fortune of hearing Don Campbell, a rancher 
from Alberta, Canada present at a conference and Don made this 
statement, ``If you want to make small changes, change the way you do 
things; if you want to make major changes, change the way you see 
things.''
    This statement changed my life. I realized that the resiliency of 
my farm was up to me. The ability of my farm to cope with climate 
change was up to me.
    As a farmer educator, I travel all over this country and have 
visited hundreds of properties. With my colleagues, I am currently 
involved with farmers and ranchers managing over 22 million acres in 
the U.S. The realities that these land managers are facing on the 
ground are alarming. One thing, however, remains constant, when a 
farmer or rancher changes how they see things, real regeneration starts 
happening
    I want to be clear: farmers and ranchers are the heart of this 
country and so many of them are incredible stewards of our land. 
However, land use, particularly the shift to our modern systems of 
agriculture in the United States and across the world has been one of 
the biggest drivers of many issues we face today such as drought, 
flooding, soil loss and erosion, and the depletion of water resources, 
often attributed broadly to ``climate change''. Through mismanagement, 
our land and our soil is now heavily degraded and in many cases barely 
functioning, or worse, completely desertified.
    Today, climate change is exacerbating the equally serious problem 
of degraded land. Scientists estimate that ``75% of land is degraded''. 
IPBES
    It's not just a question of carbon or greenhouse gases. We've 
broken the hydrological cycle, carbon storage capacity, and nutrient 
cycle. Much of our land's soil is degraded to such a state and not 
functioning as it once did.
    We have to come to grips with the reality that the current state or 
our soils is dire. We are losing 1.7 billion tons of soils annually 
(Cornell University). That is 4 tons of topsoil per acre per year on ag 
land (USDA).
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

    Continuing on this trajectory should no longer be an option.
The Economic Toll of Modern Agriculture in the U.S.

   The average debt increase for farmers is 4.1% a year since 
        1990 (USDA).

   Percentage of net farm income from government support is 
        increasing at an alarming rate; it's projected at almost 40% in 
        2020 (USDA).

   The cost of inputs, including fertilizers, herbicides, 
        pesticides, etc. is rising for farmers due to the degradation 
        of our soils.

   Crop insurance payouts continue to rise, adding a burden to 
        taxpayers.

     The cost of crop insurance has been an average $7 
            billion a year since 2013 (USDA-RMA).

    However, U.S. agriculture can and must be a major part of the 
solution. We can rebuild our soils through regenerative agriculture. 
Rebuilding our soils means rebuilding resilience, strength, and freedom 
for our nation.
    Whether your primary concern is a farmer's bottom line, rural 
economic recovery, climate mitigation, sequestering carbon, reversing 
biodiversity collapse, cleaning our water and air, rehydrating our land 
so aquifers charge and springs flow again, providing land access for 
minorities and beginning farmers, or addressing the health crisis, 
regenerative agriculture provides the solution.
    In 1991, my wife, Shelly, and I purchased a degraded ranch near 
Bismarck, ND. Soil tests showed that Soil Organic Matter levels (Soil 
Organic Matter is about 58% Carbon) were from 1.7% to 1.9%. Soil 
scientists tell me that historically, soil organic matter levels were 
between 7% to 8% in my region. This meant that approximately 75% of the 
soil carbon had been washed away or released into the atmosphere due to 
previous farming practices. This rate of soil carbon loss is all too 
common throughout the United States. Soils in North America have lost, 
on average, 20% to 75% of their carbon stock.
    I also performed water infiltration tests. They showed that my 
soils could only infiltrate \1/2\" of water per hour. This meant that 
any rain event in which I received more than that amount the water 
either ponded on the soil surface or ran off, in the case of any sloped 
land, carrying with it precious topsoil and nutrients. Top soil loss 
and artificial nutrient run off becomes problematic downstream with 
fish kills, water quality issues, and more.
On Farm Soil Comparison: Regenerative vs. Conventional
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

    In the picture you see before you, on the left-hand side of the 
screen are my soil's today (well aggregated and higher carbon levels). 
On the right-hand side of the screen are my neighbor's soils (compacted 
and mostly devoid of carbon). These samples were taken only feet apart. 
They are the same soil type. The only difference is management, or as I 
prefer to call it, stewardship.
    Today, organic matter levels on my farm are from 5.7% to 7.9%. My 
neighbors are 1.7%
    Today, my soils can infiltrate 30" of water per hour, while my 
neighbor is still lagging around \1/2\" per hour.

     That is a 60-fold increase. In places around this 
            country riddled with flooding, this could create massive 
            reductions in damage and allow for us to retain precious 
            water versus having it runoff carrying pollutants and 
            sediment.

     As I am often quoted saying, ``it is not about how 
            much rain falls, it's how well you absorb and retain it''

    Today, I do not use any synthetic fertilizer, pesticides, or 
fungicides. As a result of lower expenses and increased production my 
profits have increased tenfold.
So how does soil regeneration work?
    The soil system evolved to be self regenerating and self healing, 
otherwise there would never have been soil to begin with. So, 
rebuilding soil is all about helping nature to do it using a system 
running on carbon energized by the sun--basically, maximizing 
photosynthesis--the ability for plants to use the energy from the sun 
to take carbon from the atmosphere and pump into the soil as liquid 
energy (glucose and water).
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

Building Functioning Soil
    Nature also evolved to create functioning soil. Plants share their 
sugars with the microbes in the soil who not only make minerals and 
nutrients available to plants but also create glues that bind the soil 
particles together forming aggregates. This is what causes the primary 
difference between soil and dirt where soils contain organic matter 
(i.e., carbon-based compounds) and dirt is only mineral--sand, silt and 
clay.
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Healthy soil performs like a sponge.
    Healthy soils are able to hold 20x their weight in water due to the 
pore space between aggregates which also allows for faster infiltration 
rates. The substances building the aggregates, the glues from the 
microorganisms, and the organic matter within the aggregates are carbon 
based and often very stable (meaning it can remain as soil carbon for 
years). Thus, the CO2 in our atmosphere can and must become 
the glue that rebuilds our soils so they can function again.
How Regenerative Soil Health Practices Build Soil Carbon Over Time
Gabe Brown's Soil Carbon Data
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

    Carbon Bank/Markets: if we move this direction please take in mind 
these four areas of concern.

  1.  Integrate other outcome areas while building out carbon models so 
            they aren't separate (i.e., hydration, biomass, 
            evapotranspiration, biodiversity, etc.)

  2.  Large scale ground truthed calibration with real-time satellite 
            data so it is based on outcomes.

  3.  Make sure at least 50% of all monies from carbon (or other 
            services) make it to the farmer.

  4.  Make sure all corresponding data like precipitation, humidity 
            index, etc. are included in the baseline so equal setting 
            is created for every state and region.

    Regenerating healthy soil is the solution.

     The Benefits:

       Massive carbon sequestration potential.

        1.  Adaptive ``Regenerative'' grazing cases have shown the top 
            12" of soil 
                  are adding 4.76 tons (short U.S.) C/acre/year and 
            17.46 (short U.S.) 
                  tons CO2/acre/year.

       Increase water holding capacity and absorption.

        1.  1% increase of Soil Organic Matter means 18-25 thousand 
            more gallons 
                  per acre held.

       Biodiversity

        1.  Life in the soil means more life on the land (birds, bees, 
            game, etc. re-
                  turn)

        2.  1 teaspoon of healthy soil holds more organisms than people 
            on [E]arth.

       Resilience/risk mitigation

        1.  My colleagues and I work with hundreds of farmers totaling 
            22 million 
                  acres of land. The average we are seeing is only \1/
            2\" of water infiltrated 
                  per hour.

        2.  My farm started at this same rate and now can absorb 30" 
            rainfall per 
                  hour.

       Healthy plants and Farmer Profits

        1.  Healthy soils make healthy plants that are pest and 
            disease-resistant 
                  and require less input costs because the life in the 
            soil makes the nutri-
                  ents available to the plant.

            a.  In partnership with General Mills, Understanding Ag 
            tested 45 
                      farms that averaged 9,000 pounds of nitrogen in 
            the top foot of the 
                      soil profile.

            b.  In most cases, soils are not deficient in nutrients, 
            they are 
                      deficient in biology.

            c.  Biologically active soils can help farmers reduce input 
            costs. 7k acre 
                      farms, like Rick Clark's in Indiana, are saving 
            $860k a year on 
                      input costs.

    Why are farmers moving toward regenerative?--They want out of this 
endless cycle of debt and dependence. They want freedom. They want to 
see their sons and daughters interested in carrying on the legacy of 
their family farm. At the very least they want to provide for their 
families and keep them safe. The shift is huge, once they start working 
with nature instead of against her, their lives completely change. We 
work with every type of farmer, large, small, organic, conventional, 
wealthy, and in debt. We work with every race, religion, and creed. We 
work with White, Black, Latino, Asian, and Native American farmers. 
Regenerative agriculture came about because farmers were hurting, this 
is an incredibly interconnected movement from the soil up.

          The demand to successfully transition to regenerative 
        agriculture is here and it is growing. And it means each of you 
        can work to make sure that option is available to all farmers. 
        At the very least encourage, and if needed, facilitate early 
        adoption.

    To move to regenerative on a massive scale with any type of farming 
and ranching we have to prioritize these six principles.

     Context

       Nature always acts in context. It does not try to grow 
            plants or raise ani-
              mals out of context of where they should not be growing 
            or living.

       Programs like crop insurance are currently not based on 
            positive outcomes 
              and don't work in context, often leading to continued 
            nationwide degrada-
              tion of our soils.

         We need to monitor for real outcomes as to benefit 
            farmers building resil-
                 ience into their operations.

         Crop insurance needs to integrate environmental 
            contexts so we aren't 
                 creating unnecessary harm.

       Our financing and loan system for farmers is often out 
            of context keeping 
              farmers on an arbitrary hamster wheel of trying to pay 
            back principal bal-
              ances. It could be changed to an investment model that 
            helps farm and 
              ranch operations move to regenerative.
            
            
          Orchards in the desert. Example of bad context.

     Least Disturbance

       We have to get serious about reducing and eliminating 
            tillage.

       We have to reduce chemicals. Nature does not use copious 
            amounts of 
              chemicals.

         The chemicals, herbicides, fungicides, 
            insecticides, even the fertilizer we 
                 are putting on our crops are damaging our soils.

     Living Root

       Living roots in the soil as long as possible throughout 
            the year. Nature al-
              ways wants a living plant to take carbon out of the 
            atmosphere, through 
              photosynthesis convert it to carbon compounds that it can 
            pump into the 
              soil to feed microbes. That is what makes rebuilding soil 
            possible.

       We need a massive mobilization of multispecies cover 
            crops and mentorship 
              from experienced individuals to ensure their success. We 
            need 75% of our 
              cropland covered in the offseasons as soon as possible.

       We need viable options like roller crimpers for 
            termination of diverse cover 
              crops.

       CRP can be beneficial but it is highly underutilized for 
            actual regeneration. 
              It needs diverse mixes of species not monocultures of 
            shallow-rooted grasses 
              that have poor nutrient quality. It needs to include 
            regenerative grazing.

     Soil Armor

       Walk through the forest, there is a carpet of leaves. 
            Walk through a healthy 
              prairie and every inch is covered in plants, deep-rooted 
            grasses, and forbs. 
              Nature always wants to cover the soil to protect it from 
            wind erosion, water 
              erosion, and evaporation to keep building soil 
            aggregates.

       We have to think holistically. We have prioritize every 
            square foot of soil 
              and how well the soil is performing versus leaving 
            thousands of acres bare 
              and exposed while investing in small infrastructure 
            projects and thinking 
              we've accomplished our goal. (without armor, every bare 
            inch of soil be-
              comes vulnerable to water droplets that act like bombs to 
            soils aggregates 
              exploding them and leaving dispersed state soil easily 
            compacted and able 
              to wash away).
            
            
     Increase biodiversity

       Where in nature do you have a monoculture? The answer is 
            only where 
              human intervention has dictated it. Nature thrives on 
            diversity, yet what 
              do we do? We plant monocultures, corn, soybeans, wheat, 
            cotton, rice, and 
              the list goes on.

       As policymakers, you can help change this! Every working 
            farm, ranch, or 
              land in CRP can significantly increase the biodiversity 
            of plants, animals, 
              insects, and soil biology.

       This pint jar of soybean seed that I am holding has been 
            treated with 
              neonicotinoids and has the capability of killing 
            72,350,000 honeybees from 
              the amount of chemical alone.

     Animal Integration

       Ecosystems do not function properly without animals. 
            Many of our richest, 
              healthiest soils evolved with, and were formed in 
            partnership with, grazing 
              ruminants. Proper use of grazing ruminants are one of the 
            keys to taking 
              massive amounts of carbon out of the atmosphere, 
            especially in more brittle 
              environments that were originally grassland systems 
            maintained by large 
              herds and the indigenous people of this land.

       We must work together to bring back animals into our 
            farming systems. We 
              have to understand the profound opportunities and the 
            differences of 
              Adaptive ``regenerative'' grazed land versus 
            ``rotational'' grazing or ``contin-
              uous'' grazing.

         Compare soil carbon data--total soil carbon tons 
            per acre.
         [GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
            
          TSC.

    And, we can do this faster than we ever thought possible! As my 
associate Dr. Allen Williams says, ``outcomes that used to take us 15-
20 years we are now seeing occurring in 3-4 years.''. What he is saying 
is that the advances in how quickly farmers can regenerate landscapes, 
all while reducing input costs, continues to improve.
    This is the Chihuahuan desert in Texas. Many think that with only 
6-8" of annual rainfall it was always a desert[.]
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

    But take a close look at this picture. See the dark-colored soil 
near the surface? That is carbon. This was recently a vast grassland.
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

     This is erosion and is happening more and more across 
            the whole country. Look closely to see the barbed wire 
            going across this gully. This erosion occurred in just the 
            past 60 years.

     I want to ask you all to take this back to your own 
            states and districts. Think about places you grew up in or 
            how your grandparents described the landscape, I want you 
            to become present to the rates of land degradation that are 
            happening all around us now. Climate change is exacerbating 
            it but the management of the land is of the utmost 
            importance.

       Look for dried up streams or riverbeds. Look for bare 
            land that once was 
              vast prairie

       It's all connected. We are drying ourselves up and 
            leaving our land vulner-
              able.

    You drive through this desert and then you open a gate to enter 
Alejandro Corrillo's ranch.
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

    The difference is simply stewardship. Alejandro has used livestock 
as a tool to regenerate his soils and increase biomass. Where 12 years 
ago he needed 300 acres to feed one cow per year, he now only needs 30 
acres per cow. Note: Regenerative grazing in less brittle environments 
like Alabama see ranches going from 11 acres needed per cow/year to 2 
in under 3 years.
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

    By practicing Regenerative Agriculture we can use nature's proven, 
time-tested principles to take massive amounts of carbon out of the 
atmosphere and build it back into the soil.
4 Short Case Studies
    I want to very quickly share four case studies to show that this is 
not an anomaly for my ranch in North Dakota or Alejandro's in Texas. 
Yes, this can happen with farmers in your district.
Rick Clark (5th generation Farmer Indiana--Regenerative Organic)
   7k acres growing alfalfa, yellow field peas, cattle, soy, 
        corn, and wheat

   By moving to no-till and cover crop and planting into 
        crimped cover crop ``planting green'', he eventually removed 
        all chemical inputs (no synthetic fertilizer, pesticides or 
        fungicides ``farming nacked'')

   Savings on inputs approximately $860k annually (based 
        regional averages).

   His water infiltration rate has improved to 5" rainfall per 
        hour.

   4 bushel a year increase (for past 4 years) for corn. 1.5 
        increase for soy.
Adam Grady (11th Generation North Carolina)
   1,600 acres cattle, pasture pigs, sheep, corn beans, pasture 
        turkey, corn, and soy.

   Moved from tillage to no-till and cover w/livestock 
        integration

      ``In our second year, we saved over $200k by reducing 
            input costs such as seed, pesticides, herbicides, 
            fungicides, and fertilizer as well as reducing labor, and 
            fuel costs.
        We had also reduced Glyphosate consumption by 80% and were 
            glyphosate free by year 3.''
                                          Adam Grady Dark Branch Farms.

   Was able to seed 2 week[s] after hurricane Florence waters 
        receded while neighbors were still flooded.

   Was able to pay off his farm debt after only 3 years of 
        farming regeneratively.
Adam Chappel (Arkansas)
   the 8k acre cotton farm was spending $100 an acre on 
        herbicides, ``there was no way for us to be profitable''.

   Switched to no-till and cover cropping now they are making 
        100-250 an acre profit.

   ``I don't care what you call it, I call it profitable 
        farming''--Adam Chappel
Dr. John Boyd (4th Generation Farmer Virginia)
   1,300 acres growing corn, soy, wheat, beef cattle, goats, 
        pigs, vegetables, and hemp.

   Transitioning to regenerative practices has lead to

      Much native biodiversity being restored.

      Major water and input savings.

   Working with Tribal communities reintroducing hedgerows of 
        elderberries into lands and pastures.

   As founder of the National Black Farmers Association, John 
        works to help black farmers access NRCS soil health programs 
        and get education in regenerative management.

    This hearing is about climate change. But those of us who farm and 
ranch, it is so much more.
    By practicing Regenerative Agriculture we can use nature's proven, 
time-tested principles to not just take massive amounts of carbon out 
of the atmosphere but we can use it to build back our soils, for farms, 
families and futures.

   We can restore the water cycle and replenish underground 
        clean water sources making droughts less frequent.

   We can infiltrate water more quickly and hold more water 
        thus alleviating flooding.

   We can hold nutrients on the landscape, thus preventing 
        nitrates and phosphates from entering our watersheds.

   We can make farming and ranching profitable again by 
        reducing inputs and stacking enterprises.

   We can revitalize our rural communities by diversifying farm 
        production.

   We can produce food that is higher in nutrient density thus 
        significantly lowering healthcare costs[.]

   We can Regenerate America[.]

    Mr. Chairman, you and your Committee Members have the opportunity 
to foster this change. You can develop, adjust, or expand policy that 
will allow agriculture to be part of the solution. More resources are 
needed, but just increasing funding isn't adequate. It all starts with 
education and a ``change in how we see things.'' We must educate 
farmers and ranchers as to these regenerative principles. But it's not 
just the farmers, this is systemic, the crop advisors, the field 
agents, and all society, need more education on the ecological approach 
and how and why regeneration of the land can and must happen.
    From farmers, to soil scientists, to leading environmentalists, to 
government officials, you hear a resounding phrase, ``I didn't know''. 
Well, I didn't know either. This is an opportunity for all of us to 
learn.
    While many of these concepts are rooted in indigenous knowledge, 
many of them are being relearned and shaped by our current context and 
are emerging with science. We are living in a time like no other, we 
need science, technology, indigenous wisdom, and holistic thinking 
working together to move us toward regeneration.
    Building back healthy soil is the most cost-effective regional, 
state, and national investment. From risk mitigation to farmer 
prosperity, to human health, to carbon sequestration, it's a win, win, 
win, win, and this Committee, Mr Chairman, can help lead the way.
    Thank you for your time and I look forward to your questions.
                               Attachment
[GRAPHICS NOT AVAILABLE IN TIFF FORMAT]

    The Chairman. Thank you for your excellent testimony.
    And now, we will hear from Mr. Shellenberger. Please begin 
now.

 STATEMENT OF MICHAEL D. SHELLENBERGER, FOUNDER AND PRESIDENT, 
              ENVIRONMENTAL PROGRESS, BERKELEY, CA

    Mr. Shellenberger. Thank you very much. Thank you very much 
for inviting me. It is a pleasure to be here.
    I will just jump right in by sharing special slides that I 
have prepared for the Committee.
    So, let's see. As background, because I am going to present 
some information that may surprise some people, just my 
credentials. Time Magazine ``Hero of the Environment'' and 
Green Book Award winner. I have been working with James Hanson, 
the climate scientist, and others to protect nuclear power 
plants, but I also have a new book out on the environment 
called, Apocalypse Never. While I am an environmental advocate 
and a climate advocate, I am also concerned by a growing 
alarmism, which I think is not conducive to sober and sound 
climate or environmental policy.
    I want to draw attention to some important positive trends 
that many people don't know about. American farmers are world 
leaders in innovation, productivity, environmental protection. 
You can see here, our crop yields continue to rise dramatically 
over the last 30 years, whether it is soy, wheat, corn. You can 
see that globally we produce enough food for two billion people 
right now. I think a lot of us experienced the fact that we 
have too much food available. It is a new problem in human 
history to have so much food. We produce 25 percent more food 
than we need every year. The result is that extreme poverty has 
declined dramatically. Globally, just ten percent of all humans 
live in extreme poverty today, down from about 50 percent just 
a few decades ago. Life expectancy has increased 40 years, and 
you can see that soil erosion has declined in the United States 
40 percent, while yields have risen. A very impressive 
achievement. We have increased meat production. We have doubled 
meat production, even while reducing greenhouse gas emissions. 
Incredible success that we don't hear enough about this. A big 
part of the reason is that we have cut the feeding time for 
various animals, including chickens, while doubling their 
weight.
    You can see the big problem with degraded soils are in 
developing and poor countries, which I will come back to, but 
they are experiencing soil loss at twice the rate of wealthy 
and developed economies like the United States.
    The evidence is clear: technological change and 
agricultural modernization will significantly outweigh climate 
change in the United States and around the world. This is a 
very important report that was produced by the United Nations 
Food and Agriculture Organization in 2018 called, The Future of 
Food and Agriculture.\4\ Just to help you understand what you 
are looking at here, you can see that what it is showing is 
that whether you are an irrigated system or rain fed system, 
and whether you are in the business-as-usual scenario, the 
sustainability scenario, or a scenario of greater inequality, 
what really matters is technological change. Just think of it 
as fertilizers, mechanization, and irrigation are the big 
three, but certainly better seed types massively outweigh the 
changes to temperature. This is important because climate 
change is real. It is a serious problem. We should do something 
about it, but we are not helpless, and if farmers continue to 
do what they know how to do, which is to adapt, we are going to 
do very well.
---------------------------------------------------------------------------
    \4\ Editor's note: the report referred to is retained in Committee 
file and is available at: http://www.fao.org/3/I8429EN/i8429en.pdf.
---------------------------------------------------------------------------
    And in fact, the U.S. Government's fourth National Climate 
Assessment says very clearly that we can adapt to climate 
change through innovation and adaptation. They point to 
different seed types, crop rotations, cover crops, irrigation, 
managing heat stress, pest and disease management as the keys. 
If every nation raised its agricultural productivity to the 
level of its most successful farmers, global food yields would 
rise as much as 70 percent, and they could rise another 50 
percent if nations increase the number of crops per year to 
their full potential.
    I think that one of the most important things that the 
United States can do is to work with the World Bank and other 
institutions to help poor and developing nations to modernize 
agriculture for economic development, environmental and public 
health reasons. We saw with the coronavirus pandemic, assuming 
that the conventional explanation of the coronavirus pandemic 
is accurate, it was a spillover of a zoonotic virus, perhaps 
from a bat, and perhaps through a pangolin from low yield 
farming in south China. We need to modernize meat production, 
pull meat production away from forest frontiers. We need to 
help countries to do that. It is in all of our interests to 
modernize meat production agriculture, and there are good 
environmental reasons. You can see that because we have become 
so much more efficient globally, we have actually reduced the 
amount of land that we use for meat production, which is the 
single-largest use of the Earth's surface by humankind, by an 
area almost the size of Alaska. We know that the most efficient 
meat production in North America requires 20 times less land 
than the most efficient meat production in Africa. You can see 
there a scaled-up picture of that efficiency. We know that 
industrial meat production is far more efficient than pasture 
meat production, and produces a fraction of the carbon 
emissions, just by concentrating that meat production. In 
Brazil, we could save an area twice the size of Portugal----
    The Chairman. Thank you.
    Mr. Shellenberger.--and restore a rainforest without 
impeding agricultural expansion.
    I will just close by saying carbon emissions in the United 
States have been going down for many years. We are on track to 
meet our climate agreements. Deaths for natural disasters have 
gone down. There was some talk of increased costs of extreme 
weather events. In fact, as a share of GDP, they have gone down 
significantly.
    I would just say----
    The Chairman. Thank you.
    Mr. Shellenberger.--to somebody that is concerned about 
climate change and other issues, we should just consider the 
fact that we are in the midst of a very serious drug overdose 
epidemic, which killed about 81,000 people last year in 
contrast to extreme weather, which only killed 413.
    Thanks very much.
    [The prepared statement of Mr. Shellenberger follows:]

Prepared Statement of Michael D. Shellenberger, Founder and President, 
                  Environmental Progress, Berkeley, CA
    Good morning Chairman Scott, Ranking Member Thompson, and Members 
of the Committee. My name is Michael Shellenberger, and I am Founder 
and President of Environmental Progress, an independent and nonprofit 
research organization.\1\ I am an invited expert reviewer of the next 
assessment report by the Intergovernmental Panel on Climate Change 
(IPCC), a Time Magazine ``Hero of the Environment,'' and author of the 
2020 book on the environment, Apocalypse Never, published by 
HarperCollins.
---------------------------------------------------------------------------
    \1\ Environmental Progress is an independent nonprofit research 
organization funded by charitable philanthropies and individuals with 
no financial interest in our findings. We disclose our donors on our 
website: http://environmentalprogress.org/mission.
---------------------------------------------------------------------------
    I will make four points in my testimony:

  1.  American farmers are world leaders in innovation, productivity, 
            and environmental protection.

  2.  Technological change and agricultural modernization will 
            significantly outweigh climate change in the U.S. and 
            around the world.

  3.  Vegetarianism is not important for protecting the environment or 
            reducing greenhouse gas emissions.

  4.  The U.S. should directly and through the World Bank and other 
            institutions help poor and developing nations to modernize 
            agriculture for economic development, environmental, and 
            public health reasons.

    I will draw upon the best-available science as well as upon my 
interviews with scientists to present the evidence supporting these 
three claims and recommendation.
I. The American farmer Is a World Leader in Innovation, Productivity, 
        and Environmental Protection
    Urbanization, industrialization, and energy consumption have been 
overwhelmingly positive for human beings as a whole. From preindustrial 
times to today, life expectancy extended from thirty to seventy-three 
years.\2\ Infant mortality declined from 43 to 4 percent.\3\ From 1981 
to 2015, the population of humans living in extreme poverty plummeted 
from 44 percent to ten percent.\4\
---------------------------------------------------------------------------
    \2\ James C. Riley, ``Estimates of Regional and Global Life 
Expectancy, 1800-2001,'' Population and Development Review 31, no. 3 
(2005), 537-543, accessed January 16, 2020, www.jstor.org/stable/
3401478; ``World Population Prospects 2019: Highlights,'' United 
Nations, accessed January 14, 2020, https://www.un.org/development/
desa/publications/world-population-prospects-2019-highlights.html.
    \3\ Max Roser, et al., ``Child & Infant Mortality,'' Our World in 
Data, 2019, accessed January 16, 2020, https://ourworldindata.org/
child-mortality. The World series for 1800 to 1960 was calculated by 
Max Roser on the basis of the Gapminder estimates of child mortality 
and the Gapminder series on population by country. For each estimate in 
that period a population weighted global average was calculated. The 
2017 child mortality rate was taken from the 2019 update of World Bank 
data.
    \4\ ``PovcalNet: an online analysis tool for global poverty 
monitoring,'' The World Bank, accessed January 16, 2020, http://
iresearch.worldbank.org/PovcalNet/home.aspx.
---------------------------------------------------------------------------
    Our prosperity is made possible by using energy and machines so 
fewer and fewer of us have to produce food, energy, and consumer 
products, and more and more of us can do work that requires greater use 
of our minds and that even offers meaning and purpose to our lives.
    The declining number of workers required for food and energy 
production, thanks to the use of modern energy and machinery, increases 
productivity, grows the economy, and diversifies the workforce. Former 
farm workers who move to cities spend their money buying food, 
clothing, and other consumer products and services, resulting in a 
workforce and society that is wealthier and engaged in a greater 
variety of jobs.
    The human population growth rate peaked in the early 1960s 
alongside rising life expectancy and declining infant mortality.\5\ 
Total population will peak soon.\6\ And thanks to rising agricultural 
productivity, the share of humans who are malnourished declined from 20 
percent in 1990 to 11 percent today, about 820 million people.\7\
---------------------------------------------------------------------------
    \5\ Max Roser, Hannah Ritchie and Esteban Ortiz-Ospina, ``World 
Population Growth,'' Our World In Data, May 2019, accessed January 16, 
2020, https://ourworldindata.org/world-population-growth.
    \6\ Max Roser, Hannah Ritchie and Esteban Ortiz-Ospina, ``World 
Population Growth,'' Our World In Data, May 2019, accessed January 16, 
2020, https://ourworldindata.org/world-population-growth.
    \7\ For 1990 data: U.N. Food and Agriculture Organization, 
``Undernourishment around the world,'' The State of Food Insecurity in 
the World, 2006 (Rome: FAO, 2006), http://www.fao.org/3/a0750e/
a0750e02.pdf.
    For 2018 data: FAO, ``Suite of Food Security Indicators,'' FAOSTAT, 
accessed January 28, 2020, http://www.fao.org/faostat/en/#data/FS.
---------------------------------------------------------------------------
    Farms and cities are thus deeply connected. Cities concentrate 
human populations and leave more of the countryside to wildlife. Cities 
cover just more than half a percent of the ice-free surface of the 
[E]arth.\8\ Less than half a percent of Earth is covered by pavement or 
buildings.\9\ At the same time, humankind's use of land for agriculture 
is likely near its peak and capable of declining soon.\10\
---------------------------------------------------------------------------
    \8\ Xiaoping Liu, et al., ``High-resolution multi-temporal mapping 
of global urban land using Landsat images based on the Google Earth 
Engine Platform,'' Remote Sensing of Environment 209 (2018): 227-239, 
https://doi.org/10.1016/j.rse.2018.02.055.
    \9\ Christopher D. Elvidge, et al., ``Global distribution and 
density of constructed impervious surfaces,'' Sensors 7, no. 9 (2007): 
1962-1979, https://dx.doi.org/10.3390%2Fs7091962.
    \10\ Niko Alexandratos and Jelle Bruinsma, ``World agriculture 
towards 2030/2050: the 2012 revision,'' Agricultural Development 
Economics Division, Food and Agriculture Organization of the United 
Nations, June 2012, accessed January 16, 2020, http://www.fao.org/3/a-
ap106e.pdf. The UN FAO projects that arable land and permanent crop 
area will stay nearly flat through 2050, as detailed from its report on 
the subject.
---------------------------------------------------------------------------
    As wealthy nations develop and farms become more productive, 
grasslands, forests, and wildlife are returning. Globally, the rate of 
reforestation is catching up to a slowing rate of deforestation.\11\ 
The key is producing more food on less land. While the amount of land 
used for agriculture has increased by eight percent since 1961, the 
amount of food produced has grown by an astonishing 300 percent.\12\
---------------------------------------------------------------------------
    \11\ FAO, ``Data,'' FAOSTAT, accessed October 26, 2019, http://
www.fao.org/faostat/en/#data. The FAO finds reforestation in Europe, 
Asia, North America, and the Caribbean. Central America, South America, 
Africa, and Oceania are still deforesting. The global rate of 
deforestation has been cut by over half since 1990, from 7.3 million to 
3.3 million hectares per year as reforestation accelerated.
    \12\ Global FAO, ``Data,'' FAOSTAT, accessed October 26, 2019, 
http://www.fao.org/faostat/en/#data. Per FAO, global per capita 
kilocalorie production was 2196 in 1961, and 2884 in 2013. Along with 
the population rise from 3.1 to 7.2 billion between 1961 and 2013, 
global food production has tripled. Global land for agriculture 
increased from 4.5 to 4.8 billion hectares over the same period
---------------------------------------------------------------------------
    Though pastureland and cropland expanded 5 and 16 percent, between 
1961 and 2017, the maximum extent of total agriculture land occurred in 
the 1990s, and declined significantly since then, led by a 4.5 percent 
drop in pasture land since 2000.\13\ Between 2000 and 2017, the 
production of beef and cow's milk increased by 19 and 38 percent, 
respectively, even as total land used globally for pasture shrank.\14\
---------------------------------------------------------------------------
    \13\ Global FAO, ``Data,'' FAOSTAT, accessed October 26, 2019, 
http://www.fao.org/faostat/en/#data.
    \14\ Global FAO, ``Data,'' FAOSTAT, accessed October 26, 2019, 
http://www.fao.org/faostat/en/#data.
---------------------------------------------------------------------------
    The replacement of farm animals with machines massively reduced 
land required for food production. By moving from horses and mules to 
tractors and combine harvesters, the United States slashed the amount 
of land required to produce animal feed by an area the size of 
California. That land savings constituted an astonishing \1/4\ of total 
U.S. land used for agriculture.\15\
---------------------------------------------------------------------------
    \15\ USDA, Changes in Farm Production and Efficiency: A Summary 
Report, Statistical Bulletin 233 (Washington, D.C.: USDA, 1959), 12-13.
---------------------------------------------------------------------------
    Today, hundreds of millions of horses, cattle, oxen, and other 
animals are still being used as draft animals for farming in Asia, 
Africa, and Latin America. Not having to grow food to feed them could 
free up significant amounts of land for endangered species, just as it 
did in Europe and North America.
    Energy is required for all of this agricultural modernization. 
Thanks to fertilizers, irrigation, petroleum-powered tractors, and 
other farm machines, the power densities of farms rise ten-fold as they 
evolve from the labor-intensive techniques used by small farmers in 
poor nations to the energy-intensive practices used on California's 
rice farms.\16\
---------------------------------------------------------------------------
    \16\ Vaclav Smil, Power Density (Cambridge: The MIT Press, 2016), 
168.
---------------------------------------------------------------------------
    American farmers embraced the digital revolution starting in the 
1990s. It was then that they started using GPS for auto-steering 
combines and other farm machinery, significantly reducing both overlaps 
and gaps in fields. Farmers mapped soils and used new equipment to 
apply chemicals at precise and variable rates specific to different 
soils. GPS also opened up precision agriculture, as it is called. 
Special equipment can space seeds precisely, while genetic engineering 
helps farmers guard against insects and weeds with fewer and less toxic 
chemicals.
    Conventional agriculture is used on 99 percent of U.S. cropland and 
is responsible for significant environmental improvements to farming. 
The total amount of pesticides applied to U.S. crops declined 18% 
between 1980 and 2008 and is today 80 percent lower than their 1972 
peak.\17\ Total fertilizer use in the U.S. peaked in 1981 and hasn't 
risen since, despite an increase in total crop production of 44 
percent, according to the Environmental Protection Agency.\18\
---------------------------------------------------------------------------
    \17\ Jorge Fernandez-Cornejo, et al., ``Pesticide Use Peaked in 
1981,'' USDA Economic Research Service, June 2, 2014. ers.usda.gov.
    \18\ Environmental Protection Agency, ``Report on the 
Environment,'' accessed February 18, 2021. www.epa.gov.
---------------------------------------------------------------------------
    The use of water per unit of agricultural production has been 
declining as farmers have become more precise in irrigation methods. 
Irrigation water used per bushel of corn has declined by nearly half 
since 1980, while greenhouse gases declined 31 percent.\19\
---------------------------------------------------------------------------
    \19\ Field to Market, ``Environmental and Socioeconomic Indicators 
for Measuring Outcomes of On-Farm Agricultural Production in the 
U.S.,'' December 2016. www.field tomarket.org.
---------------------------------------------------------------------------
    High-yield farming is also better for soils. Eighty percent of all 
degraded soils are in poor and developing nations of Asia, Latin 
America, and Africa. The rate of soil loss is twice as high in 
developing nations as in developed ones. Thanks to the use of 
fertilizer, wealthy European nations and the United States have adopted 
soil conservation and no-till methods, which prevent erosion. In the 
United States, soil erosion declined 40 percent in just fifteen years, 
between 1982 and 1997, while yields rose.\20\
---------------------------------------------------------------------------
    \20\ USDA, ``Changes in Erosion 1982-1997,'' United States 
Department of Agriculture, January 4, 2001, https://www.nrcs.usda.gov/
wps/portal/nrcs/detail/soils/ref/?cid=nrcs143_013911; FAO, ``Data,'' 
FAOSTAT, accessed January 27, 2020, http://www.fao.org/faostat/en/
#data. FAO data on crop yields show almost every major crop increasing 
in yield in the United States between 1982 and 1997.
---------------------------------------------------------------------------
II. Technological Change and Agricultural Modernization Will 
        Significantly Outweigh Climate Change in the U.S. and Around 
        the World
    In 2019 the Intergovernmental Panel on Climate change warned that 
warming of 1.5 C above pre-industrial temperatures would cause ``long-
lasting or irreversible'' harm. The New York Times reported that 
planetary warming threatens to worsen resource scarcity, and ``floods, 
drought, storms and other types of extreme weather threaten to disrupt, 
and over time shrink, the global food supply.'' \21\
---------------------------------------------------------------------------
    \21\ Christopher Flavelle, ``Climate Change Threatens the World's 
Food Supply, United Nations Warns,'' New York Times, August 8, 2019, 
https://www.nytimes.com.
---------------------------------------------------------------------------
    But there is little to no scientific basis for claims that climate 
change will reduce agricultural productivity globally. ``It's difficult 
to see how we could accommodate eight billion people or maybe even half 
of that,'' said Swedish agronomist Johan Rockstrom of the Potsdam 
Institute in Germany, if temperatures rise four or more degrees above 
preindustrial levels.\22\ But when I asked Rockstrom by telephone for 
the scientific studies supporting his claim, he said, ``I must admit I 
have not seen a study.'' \23\
---------------------------------------------------------------------------
    \22\ Gaia Vince, ``The Heat is On Over the Climate Crisis. Only 
Radical Measures Will Work,'' Guardian, May 18, 2019, https://
www.theguardian.com.
    \23\ Johan Rockstrom (director of the Potsdam Institute for Climate 
Impact Research) in discussion with the author, November 27, 2019.
---------------------------------------------------------------------------
    In fact, scientists have done that study--two are Rockstrom's 
colleagues at the Potsdam Institute--and they found that food 
production could increase even at 4 to 5 C warming above 
preindustrial levels, and they found that technical improvements, such 
as fertilizer, irrigation, and mechanization, mattered more than 
climate change.\24\
---------------------------------------------------------------------------
    \24\ Hans van Meijl, et al., ``Comparing impacts of climate change 
and mitigation on global agriculture by 2050,'' Environmental Research 
Letters 13, no. 6 (2018), https://iopscience.iop.org/article/10.1088/
1748-9326/aabdc4/pdf.
---------------------------------------------------------------------------
    Food production would only decline in the U.S. and North America if 
the American farmer stopped innovating and adapting, which is counter 
to the nature of farmers. IPCC finds that there would be net 
agricultural productivity declines ``without adaptation'' and that the 
productivity of agriculture in some parts of North America will improve 
with warmer temperatures. Some of the yield increases in recent decades 
came from rising temperatures in Canada and greater precipitation in 
the U.S. Where water is not a limiting factor, rising temperatures will 
increase productivity in North America, unless farmers stop innovating 
and adapting.\25\
---------------------------------------------------------------------------
    \25\ Romero-Lankao, P., J.B. Smith, D.J. Davidson, N.S. 
Diffenbaugh, P.L. Kinney, P. Kirshen, P. Kovacs, and L. Villers Ruiz, 
2014: North America. In: Climate Change 2014: Impacts, Adaptation, and 
Vulnerability. Part B: Regional Aspects. Contribution of Working Group 
II to the Fifth Assessment Report of the Intergovernmental Panel on 
Climate Change [Barros, V.R., C.B. Field, D.J. Dokken, M.D. 
Mastrandrea, K.J. Mach, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. 
Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, 
P.R. Mastrandrea, and L.L. White (eds.)]. Cambridge University Press, 
Cambridge, United Kingdom and New York, NY, USA, pp. 1444, 1462.
---------------------------------------------------------------------------
    There is very good reason to believe that American farmers will 
adapt well to climate change. ``The North American agricultural 
industry has the adaptive capacity to offset projected yield declines 
and capitalize on opportunities under 2 warming,'' IPCC writes, 
including through genetically modified seeds. Many of these practices 
bring other economic and environmental benefits. Low- and no-till 
farming reduces soil erosion, allows for the retention of moisture, and 
reduces greenhouse gases.\26\
---------------------------------------------------------------------------
    \26\ Romero-Lankao, P., J.B. Smith, D.J. Davidson, N.S. 
Diffenbaugh, P.L. Kinney, P. Kirshen, P. Kovacs, and L. Villers Ruiz, 
2014: North America. In: Climate Change 2014: Impacts, Adaptation, and 
Vulnerability. Part B: Regional Aspects. Contribution of Working Group 
II to the Fifth Assessment Report of the Intergovernmental Panel on 
Climate Change [Barros, V.R., C.B. Field, D.J. Dokken, M.D. 
Mastrandrea, K.J. Mach, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. 
Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, 
P.R. Mastrandrea, and L.L. White (eds.)]. Cambridge University Press, 
Cambridge, United Kingdom and New York, NY, USA, pp. 1463.
---------------------------------------------------------------------------
    The U.S. Government's Fourth National Climate Assessment supports 
IPCC's findings. It similarly suggests that the risks of climate change 
to U.S. farmers will be mitigated by innovation and adaptation. Farmers 
can adapt by changing what they produce, altering productive inputs 
including seed type, and using new technologies. Farmers can alter crop 
rotations, use different cover crops, and deploy irrigation. Farmers 
can manage heat stress among life stock by changing breeds and diets, 
providing shade, and altering patterns of feeding and reproduction. The 
Assessment points to pest and disease management, climate forecasting 
tools, and crop insurance as proven effective ways to reduce risk and 
increase productivity and efficiency.\27\
---------------------------------------------------------------------------
    \27\ US Global Change Research Program, U.S. Government, ``Fourth 
National climate Assessment, Chapter 10: Agriculture and Rural 
Communities,'' 2017.
---------------------------------------------------------------------------
    Human beings around the world today produce 25 percent more food 
than we consume, and experts agree surpluses will continue to rise in a 
warmer world so long as poor nations gain access to fertilizer, 
irrigation, roads, and other key elements of modern agriculture.\28\ 
The FAO projects that even farmers in the poorest regions today, like 
sub-Saharan Africa, may see 40 percent crop yield increases from 
technological improvements alone.\29\ It concludes that food production 
will rise 30 percent by 2050 except in a scenario it calls Sustainable 
Practices is adopted, in which case it would rise 20 percent.\30\
---------------------------------------------------------------------------
    \28\ United Nations Food and Agriculture Organization (FAO), The 
future of food and agriculture--Alternative pathways to 2050 (Rome: 
Food and Agriculture Organization of the United Nations, 2018), 76-77.
    \29\  Food and Agricultural Association of the United Nations 
(FAO), The future of food and agriculture--Alternative pathways to 2050 
(Rome: United Nations, 2018), 76-77.
    \30\ FAO, The future of food and agriculture--Alternative pathways 
to 2050 (Rome: United Nations, 2018), accessed December 16, 2019, 
http://www.fao.org/global-perspectives-studies/food-agriculture-
projections-to-2050/en.
---------------------------------------------------------------------------
    Roughly 40 percent of the planet has seen ``greening''--more forest 
and other biomass growth--between 1981 and 2016. Some of this greening 
is due to a reversion of former agricultural lands to grasslands and 
forests, and some of it is due to deliberate tree planting, 
particularly in China.\31\ This is even true in Brazil. While the 
world's attention has been focused on the Amazon, forests are returning 
in the southeast, which is the more economically developed part of 
Brazil. This is due to both rising agricultural productivity and 
environmental conservation.\32\
---------------------------------------------------------------------------
    \31\ Jing M. Chen, et al., ``Vegetation structural change since 
1981 significantly enhanced the terrestrial carbon sink,'' Nature 
Communications 10, no. 4259 (October 2019): 1-7, https://
www.nature.com/articles/s41467-019-12257-8.pdf.
    \32\ Alberto Barretto, et al., ``Agricultural intensification in 
Brazil and its effects on land-use patterns: an analysis of the 1975-
2006 period,'' Global Change Biology 19 (2013): 1804-15, https://
doi.org/10.1111/gcb.12174. ``The significant reduction in deforestation 
that has taken place in recent years, despite rising food commodity 
prices, indicates that policies put in place to curb conversion of 
native vegetation to agriculture land might be effective. This can 
improve the prospects for protecting native vegetation by investing in 
agricultural intensification.''
---------------------------------------------------------------------------
    Part of the reason the planet is greening stems from greater carbon 
dioxide in the atmosphere, and greater planetary warming.\33\ 
Scientists find that plants grow faster as a result of higher carbon 
dioxide concentrations. From 1981 to 2016, four times more carbon was 
captured by plants due to carbon-boosted growth than from biomass 
covering a larger surface of Earth.\34\
---------------------------------------------------------------------------
    \33\ Jing M. Chen, et al., ``Vegetation structural change since 
1981 significantly enhanced the terrestrial carbon sink,'' Nature 
Communications 10, no. 4259 (October 2019): 1-7, https://
www.nature.com/articles/s41467-019-12257-8.pdf.
    \34\ Jing M. Chen, et al., ``Vegetation structural change since 
1981 significantly enhanced the terrestrial carbon sink,'' Nature 
Communications 10, no. 4259 (October 2019): 1-7, https://
www.nature.com/articles/s41467-019-12257-8.pdf.
---------------------------------------------------------------------------
    All else being equal, it would be best for global temperatures to 
remain stable. We should not want them to either rise or decline. The 
reason is because we have built our civilization based on current 
temperatures.
    But all else isn't equal. The cause of climate change is rising 
energy consumption, and that energy consumption has been necessary for 
the 90 percent decline in natural disaster deaths, the 25 percent and 
rising global food surplus, and the 30 percent decline in the global 
burden of disease.
    Some have suggested that climate change will make diseases like 
COVID-19 more frequent or more severe, but the main factors behind the 
novel-coronavirus pandemic had nothing to nothing to do with climate 
change and everything to do with the failure of the Chinese regime to 
protect public health.
    Governments and farmers have known what ``biosecurity'' measures to 
take for decades, and enacted them, partly, in response to the 2005 
avian flu (H5N1) epidemic. These measures include hardened facilities 
to prevent, for example, bats, from entering buildings; the regular 
testing of animals and workers; and disallowing live animals from being 
transported and sold at markets.\35\
---------------------------------------------------------------------------
    \35\ ``Should We Domesticate Wild Animals to Prevent Disease 
Pandemics? An Interview with Peter Daszak,'' Environmental Progress, 
May 21, 2020.
---------------------------------------------------------------------------
    Other scientists find similar outcomes. The UN Food and Agriculture 
concludes that food production will rise 30 percent by 2050 unless 
``sustainable practices'' are adopted--in which case it would rise just 
10 to 20 percent.\36\ And a paper published in Nature in 2019 found 
that ``agro-ecological'' farming, which has long been promoted by 
European governments, U.S. NGOs, and the UN, does not improve the 
agricultural productivity of small African farmers.\37\
---------------------------------------------------------------------------
    \36\ United Nations Food and Agriculture Organization (FAO), The 
future of food and agriculture--Alternative pathways to 2050 (Rome: 
Food and Agriculture Organization of the United Nations, 2018), p. 76-
77.
    \37\  Marc Corbeels, et al., ``Limits of conservation agriculture 
to overcome low crop yields in sub-Saharan Africa,'' July 16, 2020. For 
examples of efforts to promote agroecology see Shiny Varghese, 
``Agroecological and other innovative approaches for sustainable 
agriculture and food systems that enhance food security and 
nutrition,'' Institute for Agriculture and Trade Policy, June 26, 2019.
---------------------------------------------------------------------------
    In the summer of 2020, politicians and the news media pointed to 
climate change as the cause of historic, high-intensity ``megafires'' 
in California and Oregon, but leading forest scientists said fire 
suppression and the accumulation of wood fuel, not climate change, were 
what made California's fires more intense.
    ``Climate dries the [wood] fuels out and extends the fire season 
from 4-6 months to nearly year-round but it's not the cause of the 
intensity of the fires,'' said U.S. Forest Service scientist Malcolm 
North. ``The cause of that is fire suppression and the existing debt of 
wood fuel.'' North estimates that there is five times more wood fuel in 
California's forests, on average, than before Europeans arrived.
    A large, well-managed forest turned a high-intensity fire into a 
low-intensity one, proving that how forests are managed outweighs the 
higher temperatures and longer fire season caused by climate change. In 
2013, after a high-intensity megafire known as the Rim Fire in the 
Stanislaus Forest reached Yosemite National Park, where prescriptive 
burning had occurred, it became [1] a surface fire. 
Similarly, the high-intensity Rough Fire of 2015 turned into a surface 
fire after it reached Sequoia National Park, whose managers had been 
using prescribed burns for decades.
---------------------------------------------------------------------------
    \[1]\ https://fireecology.springeropen.com/articles/10.1186/s42408-
019-0041-0.
---------------------------------------------------------------------------
    The evidence for the efficacy of what foresters call ``fuel 
treatment,'' through selective logging, prescribed burning, or both, 
can also be found on U.S. Forest Service lands. In 2014, areas where 
there had been selective logging and prescribed burning survived the 
high-intensity King megafire Eldorado National Forest. Similarly, the 
2018 Carr fire burned through areas where there had been treatment of 
wood fuels over the last 3 decades. Even so, areas that had prescribed 
fire within the last 5 years, particularly the last 3 years, did 
better. Such cases are powerful evidence that selective logging and 
prescribed burning could allow many forests in California and elsewhere 
to survive climate change.
III. Vegetarianism Is Not an Important Factor for Protecting the 
        Environment
    In 2019, the Intergovernmental Panel on Climate Change (IPCC) 
published a special report on food and agriculture. ``Scientists say 
that we must immediately change the way we manage land, produce food 
and eat less meat in order to halt the climate crisis,'' reported 
CNN.\38\ Americans and Europeans need to reduce consumption of beef and 
pork by 40 percent and 22 percent, respectively, said experts, in order 
to feed ten billion people.\39\ If everyone followed a vegan diet, 
which excludes not only meat but also eggs and dairy products, land-
based emissions could be cut by 70 percent by 2050, said IPCC.\40\
---------------------------------------------------------------------------
    \38\ Isabelle Gerretsen, ``Change food production and stop abusing 
land, major climate report warns,'' CNN, August 8, 2019, https://
www.cnn.com.
    \39\  Jen Christensen, ``To help save the planet, cut back to a 
hamburger and a half per week,'' CNN, July 17, 2019, https://
www.cnn.com.
    \40\ Cheikh Mbow, et al., ``Food Security,'' in Valerie Masson-
Delmont, et al. (eds.), Climate Change and Land: an IPCC special report 
on climate change, desertification, land degradation, sustainable land 
management, food security, and greenhouse gas fluxes in terrestrial 
ecosystems, IPCC, 2019, accessed January 21, 2020, https://www.ipcc.ch/
srccl.
---------------------------------------------------------------------------
    But the headline number in the IPCC's 2019 report, a 70 percent 
reduction in emissions by 2050, referred only to agricultural 
emissions, which comprise a fraction of total greenhouse emissions.\41\ 
As such, converting to vegetarianism might reduce diet-related personal 
energy use by 16 percent and greenhouse gas emissions by 20 percent, 
found a study, but total personal energy use by just two percent, and 
total greenhouse gas emissions by four percent.\42\
---------------------------------------------------------------------------
    \41\ Cheikh Mbow, et al., ``Food Security,'' in Climate Change and 
Land: an IPCC special report on climate change, desertification, land 
degradation, sustainable land management, food security, and greenhouse 
gas fluxes in terrestrial ecosystems (IPCC, 2019), 487
    \42\ Janina Grabs, ``The rebound effects of switching to 
vegetarianism. A microeconomic analysis of Swedish consumption 
behavior,'' Ecological Economics 116 (2015): 270-279, https://doi.org/
10.1016/j.ecolecon.2015.04.030.
---------------------------------------------------------------------------
    As such, were IPCC's ``most extreme'' scenario of global veganism 
to be realized--in which, by 2050, humans completely cease to consume 
animal products and all livestock land is reforested--total carbon 
emissions would decline by just ten percent.\43\
---------------------------------------------------------------------------
    \43\ Cheikh Mbow, et al., ``Food Security,'' in Climate Change and 
Land: an IPCC special report on climate change, desertification, land 
degradation, sustainable land management, food security, and greenhouse 
gas fluxes in terrestrial ecosystems (IPCC, 2019), 487. In ``business-
as-usual'', global greenhouse emissions will rise to 86 gigatons/year 
by 2050, and emissions from agriculture will rise to 11.6 gigatons/
year. The ``upper-bound'' scenario of 100 percent veganism would reduce 
emissions by 8.1 gigatons/year from this baseline.
---------------------------------------------------------------------------
    Another study found that if every American reduced her or his meat 
consumption by \1/4\, greenhouse emissions would be reduced by just one 
percent. If every American became vegetarian, U.S. emissions would drop 
by just five percent.\44\
---------------------------------------------------------------------------
    \44\ Gidon Eshel, ``Environmentally Optimal, Nutritionally Sound, 
Protein and Energy Conserving Plant Based Alternatives to U.S. Meat,'' 
Nature: Scientific Reports 9, no. 10345 (August 8, 2019), https://
doi.org/10.1038/s41598-019-46590-1.
---------------------------------------------------------------------------
    Study after study comes to the same conclusion. One found that, for 
individuals in developed nations, going vegetarian would reduce 
emissions by just 4.3 percent, on average.\45\ And yet another found 
that, if every American went vegan, emissions would decline by just 2.6 
percent.\46\
---------------------------------------------------------------------------
    \45\ Elinor Hallstrom, et al., ``Environmental impact of dietary 
change: a systematic review,'' Journal of Cleaner Production 91 (March 
15, 2015), https://doi.org/10.1016/j.jclepro.201y4.12.008. The best 
estimate of emissions reductions of going vegetarian was 540kg, while 
average developed nation CO2e (Annex I) is 12.44t 
CO2e.
    \46\ Robin R. White and Mary Beth Hall, ``Nutritional and 
greenhouse gas impacts of removing animals from U.S. agriculture,'' 
Proceedings of the National Academy of Sciences 114, no. 48 (2017), 
https://doi.org/10.1073/pnas.1707322114.
---------------------------------------------------------------------------
    Plant-based diets, researchers find, are cheaper than those that 
include meat. As a result, people often end up spending their money on 
things that use energy, like consumer products. This phenomenon is 
known as the rebound effect. If consumers respent their saved income on 
consumer goods, which require energy, the net energy savings would only 
be .07 percent, and the net carbon reduction just two percent.\47\
---------------------------------------------------------------------------
    \47\ Janina Grabs, ``The rebound effects of switching to 
vegetarianism. A microeconomic analysis of Swedish consumption 
behavior,'' Ecological Economics 116 (2015): 270-279, https://doi.org/
10.1016/j.ecolecon.2015.04.030.
---------------------------------------------------------------------------
    None of this means that people in rich nations can't be persuaded 
to change their diets. For example, since the 1970s, Americans and 
others in developed nations have been eating more chicken and less 
beef. The global output of chicken meat has grown fourteen-fold, from 
eight metric megatonnes to 109 metric megatonnes, between 1961 and 
2017.\48\
---------------------------------------------------------------------------
    \48\ FAO, ``Livestock Primary,'' FAOSTAT, http://www.fao.org/
faostat/en/#data/QL.
---------------------------------------------------------------------------
    The good news is that the total amount of land humankind uses to 
produce meat peaked in the year 2000. Since then, the land dedicated to 
livestock pasture around the world, according to the Food and 
Agriculture Organization of the U.N., has decreased by more than 540 
million square miles, an area 80 percent as large as Alaska.\49\
---------------------------------------------------------------------------
    \49\ FAO, World Livestock: Transforming the livestock sector 
through the Sustainable Development Goals (Rome: FAO, 2018), Licence: 
CC BY-NC-SA 3.0 IGO, http://www.fao.org/3/CA1201EN/ca1201en.pdf.
---------------------------------------------------------------------------
    All of this happened without a vegetarian revolution. Today, just 
two to four percent of Americans are vegetarian or vegan. About 80 
percent of those who try to become vegetarian or vegan eventually 
abandon their diet, and more than half do so within the first year.\50\
---------------------------------------------------------------------------
    \50\ Charles Stahler, ``How many people are vegan?'' Vegetarian 
Resource Group, based on March 7-11, 2019 Harris poll, accessed 
December 31, 2019, https://www.vrg.org/nutshell/Polls/
2019_adults_veg.htm; Kathryn Asher, et al., ``Study of Current and 
Former Vegetarians and Vegans: Initial Findings, December 2014,'' 
Humane Research Council and Harris International, accessed October 30, 
2019, https://faunalytics.org/wp-content/uploads/2015/06/
Faunalytics_Current-Former-Vegetarians_Full-Report.pdf.
---------------------------------------------------------------------------
    Developed nations like the United States saw the amount of land 
they use for meat production peak in the 1960s. Developing nations, 
including India and Brazil, saw their use of land as pasture similarly 
peak and decline.\51\ Part of this is due to the shift from beef to 
chicken. A gram of protein from beef requires two times the energy 
input in the form of feed as a gram from pork, and eight times a gram 
from chicken.\52\ But mostly it is due to efficiency. Between 1925, 
when the United States started producing chicken indoors, and 2017, 
breeders cut feeding time by more than half while more than doubling 
the weight.\53\
---------------------------------------------------------------------------
    \51\ FAO, ``Land Use,'' FAOSTAT, accessed January 27, 2020, http://
www.fao.org/faostat/en.
    \52\ A. Shepon, et al., ``Energy and Protein Feed-to-Food 
Conversion Efficiencies in the U.S. and Potential Food Security Gains 
from Dietary Changes,'' Environmental Research Letters 11, no. 10 
(2016): 105002, https://doi.org/10.1088/1748-9326/11/10/105002. Beef 
has a protein conversion efficiency of 2.5%, pork of 9%, and poultry of 
21%.
    \53\ Vaclav Smil, Should We Eat Meat? Evolution and Consequences of 
Modern Carnivory (Oxford: John Wiley & Sons, Ltd., 2013), 92. When the 
U.S. started producing chickens indoors, in 1925, it took 112 days for 
one to reach maturity. By 1960 it took half as long and chickens gained 
\1/3\ more weight. By 2017, chickens grown indoors only required just 
48 days to reach maturity and they had more than doubled in weight 
since 1925.
---------------------------------------------------------------------------
    Meat production roughly doubled in the United States since the 
early 1960s, and yet greenhouse gas emissions from livestock declined 
by 11 percent during the same period.\54\ Producing a pound of beef in 
the U.S. today requires \1/3\ less land, \1/5\ less feed, and 30 
percent fewer animals as the 1970s.\55\
---------------------------------------------------------------------------
    \54\ FAO, ``Data,'' FAOSTAT, http://www.fao.org/faostat/en/#data/
RL, cited in Frank Mitloehner, ``Testimony before the Committee on 
Agriculture, Nutrition and Forestry U.S. Senate,'' May 21, 2019, 
accessed November 3, 2019, https://www.agriculture.senate.gov/imo/
media/doc/Testimony_Mitloehner_05.21.2019.pdf.
    \55\ J.L. Capper, ``The environmental impact of beef production in 
the United States: 1977 compared with 2007,'' Journal of Animal 
Science, December 1, 2011.
---------------------------------------------------------------------------
    American cow milk production in the U.S. today requires 90 percent 
as much land and 79 percent fewer animals as it did in 1944.\56\ Fewer 
animals means \2/3\ less methane, a potent greenhouse gas, per glass of 
milk today as compared to 1950.\57\
---------------------------------------------------------------------------
    \56\ J.L. Capper, et al, ``The environmental impact of dairy 
production: 1944 compared with 2007,'' Journal of Animal Science, June 
2009.
    \57\ Frank Mitloehner, ``Testimony before the committee on 
agriculture nutrition and forestry U.S. Senate,'' May 21, 2019.
---------------------------------------------------------------------------
    Last fall I visited a milking operation owned by Matt Swanson near 
Turlock, California. I was amazed as I watched dozens of cows calmly 
eat and get milked as they slowly turned on a giant merry go-round. The 
machine was labor-saving, allowing for under a half dozen workers to 
oversee an operation with hundreds of milking cows.
IV. The U.S. Should Directly and Through the World Bank and Other 
        Institutions Help Poor and Developing Nations To Modernize 
        Agriculture for Economic Development, Environmental, and Public 
        Health Reasons
    The use of land as pasture for beef production is humankind's 
single largest use of Earth's surface. We use twice as much land for 
beef and dairy production as for our second largest use of Earth, which 
is growing crops. Nearly half of Earth's total agricultural land area 
is required for ruminant livestock, which includes cows, sheep, goats, 
and buffalo.\58\
---------------------------------------------------------------------------
    \58\ FAO, ``Land Use'' FAOSTAT, 2017, http://www.fao.org/faostat/
en/#data/RL.
---------------------------------------------------------------------------
    During the last 300 years, an area of forests and grasslands almost 
as large as North America was converted into pasture, resulting in 
massive habitat loss and driving the significant declines in wild 
animal populations. Between 1961 and 2016, pastureland expanded by an 
area almost the size of Alaska.\59\
---------------------------------------------------------------------------
    \59\ FAO, ``Land Use,'' FAOSTAT, accessed January 27, 2020, http://
www.fao.org/faostat/en. To be exact, 1.42 million km2.
---------------------------------------------------------------------------
    While people in developing countries increased their per capita 
meat consumption from 10 kilograms per year to 26 kilograms between 
1964 to 1999, people in the Congo and other Sub-Saharan African nations 
experienced no change in per capita meat consumption.\60\
---------------------------------------------------------------------------
    \60\ World Health Organization, ``Availability and changes in 
consumption of meat products,'' accessed January 23, 2020, https://
www.who.int/nutrition/topics/3_foodconsumption/en/index4.html.
---------------------------------------------------------------------------
    Activists argue that factory farms are far worse for the natural 
environment than free-range beef, but pasture beef requires fourteen to 
nineteen times more land per kilogram than industrial beef, according 
to a review of fifteen studies.\61\ The same is true for other inputs, 
including water. Highly efficient industrial agriculture in rich 
nations requires less water per output than small farmer agriculture in 
poor ones.\62\ Pasture beef generates 300 to 400 percent more carbon 
emissions per kilogram than industrial beef.\63\
---------------------------------------------------------------------------
    \61\ Durk Nijdam, Geertruida Rood and Henk Westhoek, ``The price of 
protein: Review of land use and carbon footprints from life cycle 
assessments of animal food products and their substitutes,'' Food 
Policy 37 (2012): 760-770, https://doi.org/10.1016/
j.foodpol.2012.08.002.
    \62\ David Gustafson, et al., ``Climate adaptation imperatives: 
Global sustainability trends and eco-efficiency metrics in four major 
crops--canola, cotton, maize, and soybeans,'' International Journal of 
Agricultural Sustainability 12 (2014): 146-163, https://doi.org/
10.1080/14735903.2013.846017.
    \63\ Durk Nijdam, Geertruida Rood and Henk Westhoek, ``The price of 
protein: Review of land use and carbon footprints from life cycle 
assessments of animal food products and their substitutes,'' Food 
Policy 37 (2012): 760-770, https://doi.org/10.1016/
j.foodpol.2012.08.002.
    ``Production of 1 kg of extensively farmed beef results in roughly 
three to four times as many greenhouse gas emissions as the equivalent 
amount of intensively farmed beef.''
---------------------------------------------------------------------------
    This difference in emissions comes down to diet and lifespan. Cows 
raised at industrial farms are typically sent from pastures to feedlots 
at about 9 months old, and then they are sent to slaughter at fourteen 
to eighteen months. Grass-fed cattle spend their entire lives at 
pasture and aren't slaughtered until between eighteen to twenty-four 
months of age. Since grass-fed cows gain weight more slowly and live 
longer, they produce more manure and methane.\64\
---------------------------------------------------------------------------
    \64\ Lupo, C.D., Clay, D.E., Benning, J.L., & Stone, J.J. (2013). 
Life-Cycle Assessment of the Beef Cattle Production System for the 
Northern Great Plains, USA. Journal of Environment Quality, 42(5), 
1386. doi:10.2134/jeq2013.03.0101
---------------------------------------------------------------------------
    In addition to their longer lifespans, the roughage-heavy diets 
typical of organic and pasture farm systems result in cows releasing 
more methane. These facts combined tell us that the global warming 
potential of cows fed concentrates is 4 to 28 percent lower for cows 
fed roughage.\65\
---------------------------------------------------------------------------
    \65\ M. de Vries, C.E. van Middelaar, and I.J.M. de Boer, 
``Comparing environmental impacts of beef production systems: A review 
of life cycle assessments,'' Livestock Science 178 (August 2015): 279-
288, https://doi.org/10.1016/j.livsci.2015.06.020.
---------------------------------------------------------------------------
    Attempting to move from factory farming to organic, free-range 
farming would require vastly more land, and thus destroy the habitat 
needed by endangered species. ``You simply can't feed billions of 
people free-range eggs,'' a farmer told a journalist. ``It's cheaper to 
produce an egg in a massive laying barn with caged hens. It's more 
efficient and that means it's more sustainable'' \66\
---------------------------------------------------------------------------
    \66\ Jonathan Safran Foer, Eating Animals (New York: Little Brown, 
2009), 95-96.
---------------------------------------------------------------------------
    Modernized agricultural techniques and inputs could increase rice, 
wheat, and corn yields five-fold in sub-Saharan Africa, India, and 
developing nations.\67\ Experts say sub-Saharan African farms can 
increase yields by nearly 100 percent by 2050 simply through access to 
fertilizer, irrigation, and farm machinery.\68\
---------------------------------------------------------------------------
    \67\ A. Bala, ``Nigeria,'' Global Yield Gap and Water Productivity 
Atlas, accessed January 16, 2020, http://www.yieldgap.org/en/web/guest/
nigeria; Nikolai Beilharz, ``New Zealand farmer sets new world record 
for wheat yield,'' ABC News, April 3, 2017, https://www.abc.net.au;
    Matthew B. Espek, et al., ``Estimating yield potential in temperate 
high-yielding, direct-seeded U.S. rice production systems,'' Field 
Crops Research 193 (2016): 123-132, https://doi.org/10.1016/
j.fcr.2016.04.003. While average yields for some crops like wheat have 
plateaued, there is still more room for them to increase. In 2017, a 
farmer in New Zealand produced an astonishing eight times more wheat 
than the Australian average, and five times more than the global 
average.
    \68\ FAO, The future of food and agriculture--Alternative pathways 
to 2050 (Rome: Food and Agriculture Organization of the United Nations, 
2018), 76-77.
---------------------------------------------------------------------------
    If every nation raised its agricultural productivity to the levels 
of its most successful farmers, global food yields would rise as much 
as 70 percent.\69\ If every nation increased the number of crops per 
year to their full potential, food crop yields could rise another 50 
percent.\70\
---------------------------------------------------------------------------
    \69\ Nathaniel D. Mueller, et al., ``Closing yield gaps through 
nutrient and water management,'' Nature 490 (2012): 254-257, https://
doi.org/10.1038/nature11420.
    \70\ Deepak K. Ray, ``Increasing global crop harvest frequency: 
recent trends and future directions,'' Environmental Research Letters 8 
(2013), https://doi.org/10.1088/1748-9326/8/4/044041.
---------------------------------------------------------------------------
    The most efficient meat production in North America requires twenty 
times less land than the most efficient meat production in Africa. 
Replacing wild animal meat with modern meats like chicken, pork, and 
beef would require less than one percent of the total land used 
globally for farming.\71\
---------------------------------------------------------------------------
    \71\ World average yield for chicken 14 m2/kg, pork 
17m2/kg, and 43 m2/kg for beef.
    John E. Fa, Carlos A. Peres and Jessica J. Meeuwig, ``Bushmeat 
Exploitation in Tropical Forests: an Intercontinental Comparison,'' 
Conservation Biology 16 (2002): 232-237, https://doi.org/10.1046/
j.1523-1739.2002.00275.x.
    5 million tons of bushmeat extracted in the Congo and Amazon 
basins.
    Emiel V. Elferink and Sanderine Nonhebel, ``Variations in land 
requirements for meat production,'' Journal of Cleaner Production 15, 
no. 18 (2007): 1778-1786. https://doi.org/10.1016/
j.jclepro.2006.04.003.
---------------------------------------------------------------------------
    The technical requirements for creating what experts call ``the 
livestock revolution'' are straightforward. Farmers need to improve 
breeding of animals, their diet, and the productivity of grasses for 
foraging. Increasing meat production must go hand-in-hand with 
increasing agricultural yields to improve and increase feed. In 
Northern Argentina, farmers were able to reduce the amount of land used 
for cattle ranching by 99.7 percent by replacing grass-fed beef with 
modern industrial production.\72\
---------------------------------------------------------------------------
    \72\ Ricardo Grau, Nestor Gasparri, and T. Mitchell Aide, 
``Balancing food production and nature conservation in the subtropical 
dry forests of NW Argentina,'' Global Change Biology 14, no. 5 (2008): 
985-997, https://doi.org/10.1111/j.1365-2486.2008.01554.x.
---------------------------------------------------------------------------
    The dominant form of climate policy in international bodies and 
among nations around the world emerged from 1960s-era environmental 
policies aimed at constraining food and energy supplies. These policies 
are correctly referred to as Malthusian in that they stem from the 
fears, first articulated by the British economist Thomas Malthus in 
1798, that humans are at constant risk of running out of food.
    Real world experience has repeatedly disproven Malthusianism. If it 
hadn't, there wouldn't be nearly eight billion of us. Worse, Malthusian 
ideas have been used to justify unethical policies that worsen 
socioeconomic inequality by making food and energy more expensive, 
including closing down nuclear plants.\73\
---------------------------------------------------------------------------
    \73\ Michael Shellenberger, Apocalypse Never: Why Environmental 
Alarmism Hurts Us All, HarperCollins, 2020, p. 222-249.
---------------------------------------------------------------------------
    The same report which found that agricultural modernization 
outweighs climate change also found that climate policies were more 
likely to hurt food production and worsen rural poverty than climate 
change itself. The ``climate policies'' the authors refer to are ones 
that would make energy more expensive and result in more bioenergy use 
(the burning of biofuels and biomass), which in turn would increase 
land scarcity and drive up food costs. The IPCC comes to the same 
conclusion.\74\
---------------------------------------------------------------------------
    \74\ ``This occurs because . . . land-based mitigation leads to 
less land availability for food production, potentially lower food 
supply, and therefore food price increases.'' Cheikh Mbow, et al., 
``Chapter Five: Food Security,'' in V. Masson-Delmotte, et al., eds., 
Climate Change and Land: an IPCC special report on climate change, 
desertification, land degradation, sustainable land management, food 
security, and greenhouse gas fluxes in terrestrial ecosystems (IPCC, 
2019), https://www.ipcc.ch/site/assets/uploads/2019/11/SRCCL-Full-
Report-Compiled-191128.pdf.
---------------------------------------------------------------------------
    Policymakers should explicitly reject policies that significantly 
raise food and energy prices, directly or indirectly. Republicans and 
Democrats alike should affirm their commitment to human flourishing and 
prosperity, both of which depend on cheap food and energy, which depend 
on the rising productivity of inputs to agriculture and electricity 
generation, including labor, land, and capital.
    But we should go beyond that and seek to help our brothers and 
sisters in poor nations to modernize agriculture, industrialize, and 
modernize their economies, for economic and environmental reasons. Such 
a partnership will be good for America and good for the planet.
    Thank you for inviting my testimony.
                               Attachment
[GRAPHICS NOT AVAILABLE IN TIFF FORMAT]


    The Chairman. Thank you. Thank you very much. Thank each of 
you very much.
    And now, we are going to open it up for questions at this 
time, and Members will be recognized for questions in order of 
seniority, alternating between Majority and Minority Members. 
Each Member will be recognized for 5 minutes each, in order to 
allow us to get in as many questions as we can.
    I want to start by just stressing the importance of we in 
agriculture--this hearing has been put together to address all 
of the impacts with climate change, but to make sure that we 
are addressing climate change directly as it impacts 
agriculture and our food security first.
    And so, let me start with you, Mr. Brown. You were featured 
in the documentary, Kiss the Ground, and in that clip that we 
just saw, the narrator spoke of a simple solution for many of 
the climate changes we are experiencing, and that is what we 
are looking for today at this hearing: solutions. And what that 
announcer said was this, and I quote, ``The solution is right 
under our feet.''
    Can you unpack that for us?
    Mr. Brown. I sure can. Thank you, Mr. Chairman.
    The solution is under our feet. That solution is biology, 
and it is regenerative agriculture. The way this works is that 
living plants take in sunlight through photosynthesis. They 
bring in the carbon out of the atmosphere through 
photosynthesis. They produce all these compounds, and then they 
pump that into the soil.
    Studies have shown, Dr. Teague in 2016 showed that we can 
sequester over \1/2\ of the carbon emissions annually in the 
U.S. through regenerative agriculture, through using these six 
principles that I laid out. This is not rocket science. It is 
simply using time-tested ecological principles to heal our 
planet.
    The Chairman. Now, let me ask you this, because I have been 
working very intimately with our farming interests, and there 
are two that come to mind. And I was wondering if this is an 
example of what you are talking about. One is with Bayer. Bayer 
has developed sequestration regeneration--and something called 
no-till farming, I believe. But at any rate, what they are 
doing is partnering with the farmers to get the solution that 
goes to your point, it is in the ground. It is there. 
Agriculture is agriculture for two reasons: the water coming 
from the heavens, and the carbon in the ground. Everything 
comes from that.
    And so, I wanted your opinion on what Bayer is doing, and I 
found out yesterday that some of my friends in the peanut 
industry are doing something similar. So, my point is, is this 
the kind of thing that other interests in our farming sectors 
should be doing?
    Mr. Brown. Mr. Chairman, we all need to work together to 
further these practices of regenerative agriculture. No-till 
farming first came to the United States in 1962. We have only 
approximately 25 percent of the agricultural cropland today in 
no-till systems. No-till is a small piece of the puzzle, but we 
have to do much more than that. We have to keep the soil 
covered. We have to grow diverse cash crops, diverse cover 
crops, and then we have to integrate livestock onto those 
systems.
    Yes, Bayer and other companies such as General Mills, are 
doing good things by partnering with farmers and ranchers. This 
needs to continue. It needs to be all of society coming 
together for the betterment of all.
    The Chairman. Okay. I am going to end there, because I want 
to make sure we get our Members in, as many as we can.
    I will yield to you, Ranking Member Thompson.
    Mr. Thompson. Mr. Chairman, thank you. Thank you to all 
five witnesses. All five of you, just great testimony. It just 
reaffirms, very frankly, what you are talking about are the 
things that this Committee has been dedicated to.
    I think at least 5 or 6 years ago, it was this Committee 
that had the first hearing on healthy soils in Washington. So, 
in terms of regenerative practices, it was just very 
reaffirming we have been doing the right things for a number of 
years with the Agriculture Committee.
    Great to see my friend, Zippy Duvall.
    Mr. Cantore, you probably don't remember, but you were in 
my district at the Weather Museum when you were honored in the 
Weather Hall of Fame in Punxsutawney, Pennsylvania. That is 
where we first met, and it is great to have you here with us 
today.
    I am interested in working with solutions. The Biden 
Administration and the inside the Beltway think tanks are 
pushing a climate agenda, suggesting new and shiny programs. 
However, when I hear from the farmers about climate solutions--
and that is what we should be focused on, is climate solutions. 
That should be the term that we use. They talk about the needs 
for research, more boots on the ground, access to precision 
agriculture, healthy soil practices, and the need for broadband 
connectivity to support this technology.
    Now, this all sounds like assistance available within the 
farm bill programs that are there. Not to say that we can't 
improve upon them, but it is a great base for addressing really 
effective climate solutions, continuing those.
    My question is simple. I will tee it up. I would love to 
get a response within the time I have from as many of you as 
possible. Is the solution as simple as doubling down on these 
proven programs? Why don't we start with Mr. Shellenberger?
    Mr. Shellenberger. Yes, thank you for the question.
    Absolutely. I mean, we should continue to do what we have 
been doing. There has been a case made for expanded investment 
in research and development. Research and development works 
best when it is problem-focused, when it is trying to solve 
particular problems. We have terrific history through our 
agricultural extension programs of working with American 
farmers to improve yields.
    So, yes, absolutely I think we should be continuing with 
what is working, rather than changing course into something 
really different, particularly you sometimes see proposals from 
the environmental community that would result in lower yields 
per unit of land, lower efficiencies. I think that would be a 
huge mistake. Anything that can get us to greater efficiencies 
and greater productivity is also going to be important for 
adapting to climate change.
    Mr. Thompson. Thank you. Thank you, Mr. Shellenberger.
    President Duvall, great to be with you yesterday, and good 
to see you virtually today.
    Mr. Duvall. It is good to see you, too. I appreciate the 
opportunity to be with you today.
    The Committee has worked in the right direction. If you 
just look at how much we have improved productivity 
efficiencies, and even here on my farm here, I hear people talk 
about agriculture destroying the climate. You could look at my 
farm versus where my grandfather had it. I can show you 
evidence of gulleys in the forestland that is around my farm 
from bad conservation practices back then, and now over 
several, several decades, my dad's life and my life, we have 
improved it. It is all grassland. There are no gulleys anymore 
in the fields. We are sequestering carbon. We are making sure 
that we are putting animal manure with GPS. We are using 
comprehensive nutrient management plans. All those things were 
done through some of the programs at USDA. We are heading in 
the right direction. We just need partners to help us move 
forward.
    I am concerned, if you look at the research dollars that we 
invest in our country versus the rest of the world, I am told 
that we are running behind on that. We need more research 
dollars so that we can have the new technologies and untie our 
hands. Give us a way to get the regulatory system streamlined 
so that these new products can get to the field faster, so that 
we can continue to be part of the solution to the problem.
    Mr. Thompson. Thanks, Zippy.
    Mr. Brown, congratulations on what you have been able to do 
on those 5,000 acres. I have also been on farms where I have 
seen the evidence of regenerative or healthy soil practices, 
and just right over the line, the comparison.
    I have only got a few seconds left, but I will yield to you 
for any additional responses.
    Mr. Brown. Mr. Ranking Member, thank you, and yes, the 
agencies such as NRCS have done a good job, but we need to do 
much more in the way of education. We have to educate farmers 
and ranchers as to these time-tested ecological principles in 
order to move it forward.
    It is an absolute travesty that right now, we have such a 
small amount of our landscape covered with cover crops. I fly 
extensively, and you fly anywhere, the amount of bare soil we 
see is absolutely appalling. There is no reason for that. We 
need to do more and work with these agencies to further 
education. Thank you.
    Mr. Thompson. Thank you. Thank you, Mr. Chairman.
    The Chairman. Thank you.
    I would like to take this opportunity to insert a statement 
from the National Association of State Departments of 
Agriculture, NASDA, for the record. NASDA's statement supports 
the expansion of Federal tools that incentivize climate smart 
practices.
    [The statement is located on p. 326.]
    The Chairman. And now, I would like to recognize Mr. Costa 
from California. You are recognized for 5 minutes. Is he not 
there? Mr. Costa, are you there? Are you on mute?
    Mr. Costa. I am unmuted now.
    The Chairman. Wonderful.
    Mr. Costa. Can you hear me?
    The Chairman. You are now recognized, Mr. Costa.
    Mr. Costa. Thank you. Thank you, Mr. Chairman. 
Congratulations on the first Committee hearing, and I look 
forward to working with you.
    I think this is an excellent topic to begin, climate change 
and the agricultural economy in our country. America has led 
the way in so many areas, as many of our witnesses have just 
testified for.
    I am reminded, as we discuss how we become even more 
productive and more creative, about a few facts. Some of us 
remember the old television series, Dragnet, and Sergeant 
Friday used to say, ``Just the facts, ma'am.'' Right? Well, the 
facts are the following. Food is a national security issue, and 
less than five percent of America's population are directly 
involved in the production of food and fiber.
    We have had an amazing change over the last 100 years. I am 
a third-generation farmer, but I don't farm the same way my 
parents did, nor my grandparents. And it continues to evolve 
with technology and innovation.
    Another fact: 200 years ago, we had 1\1/2\ billion people 
on the plant. A few years ago, we just clicked over seven 
billion people on the planet in less than 200 years. Climate 
change has been occurring throughout the history of our planet. 
The real question is, how much are we contributing to it?
    Well, I will tell you that in 200 years, we have gone from 
1.5 to over seven billion people. We are putting a lot more 
stuff in the air, a lot more stuff in the water, and we are 
having an impact. As a matter of fact, in 2006, I went with the 
National Academies of Science--I don't know if you can see 
this--to the South Pole for a week. This is a little vial that 
calls itself the cleanest air on Earth, but it also shows using 
isotope measuring from 1955 to 2006 that the CO2 
emissions have increased by over 300 percent. Obviously, we are 
having an impact, and American agriculture can play an 
important role, as has been cited by the statistics that have 
already been put out there. Because it matters.
    California, where I come from, where we have been farming 
for three generations in the San Joaquin Valley, is 
experiencing drought conditions again, on the heels of the 
worst drought that we had in the recorded history from 2012 to 
2017. Our snow packs that we depend upon are becoming less 
plentiful, as well as the rainfall. Ninety-nine percent of 
California's agriculture, the number one agriculture state in 
the nation, is irrigated. We have an imbalance between 
overdrafting our groundwater.
    But I firmly believe that with science and our 
productivity, we can address these issues. The ingenuity of 
America's farmers, ranchers, dairymen and -women have played a 
big part in increasing our production and the quality of our 
food. From healthy soils programs to state water efficiency 
enhancement programs, alternative manure management, and 
research and technical assistance that is occurring all around 
the country, not just in California.
    And by the way, I am a big believer in not reinventing the 
wheel. Our ag universities across the country, whether it is 
Texas A&M, whether it is the University of Georgia, whether it 
is Purdue, whether it is UC Davis or Fresno State, where I come 
from. There is a lot of good stuff going on that we ought to 
combine in terms of research and development and innovation 
with public and private partnerships.
    Let me just talk about sustainability and talk to you, 
Zippy, because you and I are both farmers, and you said it and 
I have said it. Farmers are stewards of the land. So, 
sustainability is a critical role.
    Can you talk about--I think this infrastructure package and 
the efforts that the Administration wants to deal with climate 
change is an opportunity, and I think we should look at as an 
opportunity, not only with existing farm programs, but how we 
can provide incentives to do the right thing to increase our 
productiveness. You are leading a conservation program and a 
climate change effort. How do you think we can combine these 
efforts?
    Mr. Duvall. Well, I think that if you are talking about the 
leadership that we provided to create the Food and Agriculture 
Climate Alliance, we talk about those three principles that I 
mentioned in my testimony of making sure that they are 
supported--we support voluntary market incentive-based 
programs, like some that we have, and to find new ones through 
research. We want to advance the science-based outcomes----
    The Chairman. Thank you.
    Mr. Duvall.--of it, and then, of course, all of us are very 
interested in the resilience in our rural communities and what 
we can do there.
    But it all boils down to broadband, which is part of our 
infrastructure, and research and development.
    Mr. Costa. Mr. Chairman, I have run out of time, but I 
think it would be helpful if our witnesses, and Zippy, with 
your effort, if you can write to the Committee about the 
mission and development of your coalition, and share some of 
the policy principles that the coalition sees as a fundamental 
way in which we address climate change, and look at combining 
the efforts with this infrastructure package to plus up these 
incentive-based programs and farm programs that exist today, 
and new things we might look at.
    Mr. Duvall. Yes, sir, we can do that.
    Mr. Costa. Thank you.
    The Chairman. Thanks to both of you there.
    Now moving on, I will now recognize Mr. Austin Scott of 
Georgia. You are recognized for 5 minutes.
    Mr. Austin Scott of Georgia. Thank you to my good friend, 
Chairman Scott, and to Ranking Member Thompson.
    I know that the title of the hearing is based on climate 
change, but when we talk about this, candidly, we are talking 
about environmental policy as a whole, and we are talking about 
habitat, we are talking about water. And the better we are at 
taking care of the land, the better the land will take care of 
us. I will tell you, I think we can and we should do a better 
job with the environment, and I look forward to being a part of 
that further discussion.
    One of the things that I will tell you bothers me is that 
when I see forestlands being cut down and solar panels being 
put up, when clearly there is new technology today that will do 
a better job of providing carbon-free or extremely limited 
carbon emission electricity. I think that one of the things 
that we should look at is just the facts surrounding where the 
tax credits are going with regard to that aspect of 
environmental policy. I recognize that comes through a 
different committee, but again, I want us to be reminded that 
it is environmental policy as a whole that we have to focus on, 
and not just agriculture with regard to climate change.
    The other thing I want to do is say a big thank you to Ms. 
Knox. When Hurricane Michael hit the State of Georgia, as you 
know, it was devastating to the 2nd and the 8th Districts. Had 
it not been for the University of Georgia and the other land-
grant institutions, through their research and extension 
programs that provided the information to Chairman Scott and 
Chairman Bishop and myself, then we would have not been able to 
get the additional funds for the relief from Hurricane Michael 
for our producers. And so, a big thank you to Ms. Knox. I know 
you are doing a lot of great work down there on water 
conservation and other things in my hometown of Tipton, and 
where the National Environmentally Sound Production Agriculture 
Lab is. I would certainly invite all of my colleagues on the 
Agriculture Committee to make a trip down there to see all of 
the great work that is going on at NESPA.
    Mr. Cantore, thank you so much for your coverage of 
Hurricane Michael, and what was happening to our farmers during 
that storm. The losses were astronomical, and it was your 
coverage that actually helped share our pain with the rest of 
America, and their sympathy and their prayers were much 
appreciated. I appreciate your coverage there.
    With that said, Zippy, we have been friends a long time. We 
rewrote the WHIP program with Hurricane Michael. It didn't work 
as well as we had hoped it would. What suggestions do you have 
for how the Agriculture Committee can improve the WHIP program 
as we push forward?
    Mr. Duvall. Well, Congressman, we have been friends a long 
time, and I very much appreciate the friendship. Of course, 
every time we have a disaster, it looks like it is a scurry on 
the Hill to try to get the help out to the farmers. 
Unfortunately, even though the amount of money that was finally 
delivered to Georgia, it was 18 months, 2 years later, and a 
lot of our farmers had already suffered the deadly consequence 
of it and they lost their businesses and their farms, and 
weren't able to continue farming. So, we have to find some way 
to fast track, whether it be set aside special funding for it 
with certain restrictions around it, make sure it doesn't get 
misused. But it needs to be readily available when these 
disasters hit across our country.
    Mr. Austin Scott of Georgia. Mr. Duvall, I agree with you, 
and one of the concerns I have is that if money that is 
currently set aside for our ag producers, which candidly is a 
very small percentage of the budget, when it is the largest 
portion of the economy in most of the states. I don't want to 
see that money moved into environmental policy. And again, that 
is coming from someone who thinks that we can and should take 
better care of the environment. And so, the concept of moving 
the $30 billion to environmental policy bothers me. The concept 
of doing anything with the carbon bank without an increase in 
the CCC bothers me.
    In my last few minutes, I want to say this. Mr. Brown, 
there is a lot of great work at Fort Valley State University 
with ruminants, and so, I hope you are benefitting from that. I 
do want you to know, respectfully, crop insurance is and it has 
to remain a risk management tool available for our farmers, and 
if a producer has a history of higher yields and lower losses, 
then they are rewarded with a higher average production history 
and increased amount of coverage at lower premiums. And so, if 
you have suggestions on how we improve it, I certainly am open 
to suggestions of it. But I will just tell you, production 
agriculture can't survive without some type of crop insurance 
program that rewards good farm practices. And so, that not only 
gets the environmental practices, but it gets the production 
practices as well. And so, I am open to suggestions on how to 
improve it. I thought we did a pretty good job in the 2018 Farm 
Bill to encourage people to adopt conservation measures, but I 
am not open to getting rid of the crop insurance program.
    Mr. Chairman, my time has expired, I know, but I 
appreciate, again, everybody for their work on this, and again, 
Hurricane Michael taught all of us from Georgia and Florida big 
lessons on the value of insurance and the environment, and we 
can and we should do a better job.
    With that, I yield back.
    The Chairman. And I just want to recognize also those words 
that you said, and also take a moment to compliment you in 
helping provide the leadership for us after Michael. And you so 
eloquently stated that Georgia was slammed, and thank you, 
Austin, for pulling together. We went together, you, Mr. 
Sanford Bishop, and myself, got money down there. So, we want 
to thank you, and the young lady from the University of 
Georgia.
    Now, I will recognize Mr. McGovern, the gentleman from 
Massachusetts, for 5 minutes. You may need to unmute. Oh, he 
is? Can we get one of our technicians? He's on? Good. All 
right. We will get working on it. Jim, they should get it 
cleared momentarily.
    Mr. McGovern. Can you hear me now?
    The Chairman. Yes, I hear you a little.
    Mr. McGovern. Okay. All right.
    The Chairman. I hear you.
    Mr. McGovern. All right.
    The Chairman. Go ahead, Jim.
    Mr. McGovern. All right. First of all, let me just say 
thank you, Chairman Scott, for organizing this hearing. I think 
it is a long overdue conversation, and I want to take just a 
moment to underscore the sense of urgency that we should all be 
feeling.
    We have an extremely narrow window to limit warming to 
1.5 C to avoid the most devastating impacts of climate change, 
full stop. That means we need to achieve net zero emissions 
across our entire economy, including agriculture, and it means 
we need to prepare our farmers for the impacts of even the 
best-case scenario of 1.5. That level of warming will still be 
hugely consequential, and it is already happening.
    Now, this might be news to some of my colleagues, but it is 
not news to farmers. Farmers are not the ones who got us into 
this mess, but now, they are on the frontlines of the climate 
crisis. We need to think big to help them build resilience into 
everything that they do, and we need to ensure that they have a 
seat at the table.
    Now, Mr. Brown, I want to thank you for sharing your story 
of making ecological balance the heart of land stewardship. I 
think there are both economic and ecological benefits that can 
be achieved here, and I am reminded of the work that went into 
developing standards for organic producers, which was a 
collaborative process. Many organic producers live by the 
practice you mentioned, while adhering to strict program 
standards. When farmers transition to organic, they are taking 
a risk, but having standards means that they have a roadmap and 
a path to building consumer trust.
    I want to make sure that we are providing real guidance and 
real support to farmers who are eager to follow your example. I 
think we need to have a roadmap that has integrity. So, could 
you please discuss what work lies ahead to develop standards 
for adopting regenerative techniques that will produce clarity 
to both farmers and consumers? Again, organic farming is good 
for the environment, and consumers have confidence in it 
because of the standards. I wonder if you could respond with 
your thoughts to that question.
    Mr. Brown. Thank you, Representative McGovern.
    First, I need to just briefly jump back and address--there 
was a couple prior questions that were brought up that I did 
not get a chance to answer.
    Representative Costa talked about the need to sustain what 
we are doing and to be sustainable. I am sorry, but I have 
spent a great deal of time in the Central Valley of California, 
and with all due respect, that is some of the most degraded 
land in the United States. Do any water infiltration test 
there, and you will see how degraded those soils are.
    Representative Scott, I did not at all say we needed to end 
crop insurance. That is not what I said at all. I simply said 
that we need to make it outcome-based, and that outcome cannot 
be solely yield, because yield comes at a detriment to the 
environment. We also have to realize that in regenerative 
agricultures, we increase the amount of nutrient-dense food 
grown per acre. There is a misconception out there that 
regenerative practices mean less yield. That is not at all 
true. I produce now literally 30 times as much nutrient-dense 
food per acre than I did before I started these regenerative 
practices.
    Now, Mr. McGovern, to answer your question. Yes, we do need 
standards. The business that I work for, Understanding Ag, we 
work with a lot of organic producers leading them down this 
path. Organic is good, but we can do better because we can 
minimize the amount of tillage that they are doing. We can also 
increase diversity, increase the use of cover crops, produce 
more nutrient-dense food, and then through Acts such as the 
PRIME Act, we will be able to add value to the goods that they 
are producing. Regenerative agriculture is a time-tested, 
proven pathway to heal not only our land in respect to climate 
change, but we can heal our communities, the profitability on 
our farms and ranches, water quality, water quantity issues, 
and many of the other things that we are currently facing as a 
challenge in society today.
    Mr. McGovern. Thank you. I appreciate your answer very 
much.
    I think my time is up, but I just think it is important for 
all of us here to be focused on actually building a roadmap 
with standards, because otherwise, we are just talking the talk 
and we are not walking the walk. Again, I think the organic 
example is an example that we should follow.
    But thank you very much. I yield back.
    Mr. Brown. And we do have that roadmap.
    Mr. McGovern. Thank you.
    The Chairman. Thank you very much, Mr. McGovern.
    And now, I recognize for 5 minutes Congressman Crawford 
from Arkansas.
    Mr. Crawford. Thank you, Mr. Chairman. I appreciate it.
    Mr. Duvall, thanks for being here today. I wanted to visit 
with you a little bit about some of the things that you know 
about our district. We are the largest agriculture district in 
Arkansas, produce about \1/2\ of the U.S. rice crop in my 
district. But, also a lot of production in other crops like 
cotton, soybeans, a big producer.
    A lot of the climate dialogue related to agriculture is 
centered around carbon sequestration. I think it is important 
to recognize that the diversity of agriculture demands that 
there is not a one single solution approach that is appropriate 
for every crop or every cropping system, or every region. But 
there are some unique considerations to each of those areas and 
systems.
    Rice farmers are some of the most sustainability-minded 
producers I think we have in the country, and they have 
employed considerable techniques to increase efficiency, reduce 
greenhouse gas emissions, and water use. And also, creating 
excellent wetland habitat, which are very biodiverse with 
numerous species of waterfowl, as you know. You have probably 
even harvested some of those yourself.
    My question to you, though, Mr. Duvall, is that one of the 
great things about the farm bill conservation programs is that 
they are flexible enough to help any farmer that wants to 
address a natural resource concern that is important to their 
farm. Whether it is a rice farmer that wants to work on water 
management, or a rancher that wants to put up fencing, the 
program allows farmers to decide. And I worry about a carbon 
bank being accessible to everyone, and providing a level of 
flexibility. Do you share that concern?
    Mr. Duvall. I do share that concern, Congressman, and 
farmers are concerned that we start a carbon bank, and then 
some company in between the farmer and the people that are 
buying the carbon credits makes all the money. What we need is 
something that generates some additional income at the farm 
level so that we can continue to do conservation practices. We 
need partners, and of course, USDA is a great partner and has 
been for years and years and years, and we look forward to not 
just accelerating those programs to go from 30 to 40 percent of 
cover crop to, hopefully 100 percent one day, and kind of 
follow some of the principles that we heard Mr. Brown speak of.
    But education is a key part, and he mentioned that, too. 
But we need partners, and the carbon credit bank and moving in 
that direction, we do have concerns in that area whether or not 
it will be available to everyone.
    Mr. Crawford. You mentioned partners, and I know you 
mentioned in your testimony that you are working with Food and 
Agriculture Climate Alliance, which has been very focused on 
cover crops and soil health, as you also mentioned, related to 
carbon sequestration. And as you know, and as I mentioned 
before, rice producers hold water in their fields in the off 
season that provides habitat for waterfowl. It also helps 
decompose rice straw from the previous growing season. So, in 
effect, ducks are our cover crop. It appears that the policies 
that FACA has identified to sequester carbon might only work 
for a couple of commodities. If the government provides an 
incentive that is coupled to one or two commodities, then we 
could see drastic shifts in plantings and markets. I am just 
asking if you can look into that and work with them and with us 
to make recommendations to make sure that we are able to avoid 
that, and we find a solution to work for all commodities.
    Mr. Duvall. I would agree with that, and we are very 
concerned that a lot of the practices that farmers have been 
doing for decades now have been sequestering carbon all that 
time won't get recognized if we move forward, too. The rice 
farmers, the pasture and cropland management we have already 
done, forestry, all those farmers have been sequestering carbon 
for years and years and years, and we need to recognize what 
they have done in the past, too.
    Mr. Crawford. I appreciate that. Thank you, Mr. Duvall, and 
Mr. Chairman, I will yield back.
    The Chairman. Excuse me. I wasn't on.
    Now, I recognize, for 5 minutes, Ms. Adams of North 
Carolina.
    Ms. Adams. Thank you, Mr. Chairman, and to the Ranking 
Member as well for hosting today's hearing, and thank you to 
our witnesses for their testimony.
    This is such an important topic. Climate change is a 
crisis, and we must treat it like one. It is already impacting 
our nation in deadly and destabilizing ways. And like this 
pandemic, its impacts are being felt disproportionately by the 
most vulnerable among us. Today's testimony has further 
enforced that the climate crisis is also threatening our 
farmers' ability to grow food in productive and environmentally 
sustainable ways, which could have detrimental impacts all the 
way up and down the food supply chain.
    When talking about climate change and how it will impact 
the agriculture sector, I also want to make sure that we are 
strongly considering the role of our 1890 land-grant 
institutions and the role they can play. These institutions, 
such as North Carolina A&T State University, my alma mater, 
have incredible expertise in conducting agriculture research 
and providing extension services to farmers and ranchers, 
particularly socially disadvantaged producers. I was proud that 
our Committee included provisions within the American Rescue 
Plan Act that will support these institutions, their students, 
including resources for research and education and extension.
    Professor Knox, I know that you are with the University of 
Georgia, but I assume that you work with research and extension 
professionals at other land-grant institutions. So, my question 
is, can you provide more detail on how you collaborate with 
other institutions, particularly with the professionals at 1890 
institutions such as Fort Valley State University?
    Ms. Knox. Yes, Congresswoman Adams, I am happy to answer 
that. As you might not be too surprised to know, Fort Valley is 
the group that I work with the most, since I do a lot of my 
work with Georgia. We have had a number of research projects 
that have specifically included folks from Fort Valley as part 
of a consortium of researchers. Quite often those not only are 
in Georgia, but they also include other researchers from 
Florida and Alabama. And so, we draw not from just 1890s group, 
but also from other universities. But they serve a very crucial 
role in our research because they have an audience that we 
really need to reach. We need to take our scientific knowledge 
and make it useful to a variety of farmers, including a lot of 
the Black farmers and minority farmers that have very unique 
needs. A lot of them don't run really big farms. A lot of them 
are growing specific kinds of crops, and we need to be aware of 
those needs and really respond to them. And that is where the 
1890s institutions really fall in, because they can help 
translate the science that is being done by the researchers to 
the farmers that are part of the community. And so, by doing 
that, they serve really a critical role.
    Ms. Adams. Great, thank you, and you've answered part of my 
next question in terms of what role our institutions in 
supporting research and education and extension related to 
climate change, what is their role? And are there ways that we 
can further empower 1890 land-grants to support this ongoing 
work or to strengthen their collaboration with institutions 
like yours to expand opportunities?
    Ms. Knox. Yes, I think that there are always ways to 
include, say, multi-university consortiums to do more research, 
and I think there can be ways to say we really want to 
encourage the 1890s land-grant institutions to participate in 
that. And so, I know in the past some of the research groups I 
have been on have specifically asked for those kind of 
partnerships, and I would like to see that continue or maybe 
even expand so that we can really use that expertise from the 
1890s universities.
    Ms. Adams. Great, thank you.
    Mr. Brown, you mentioned carbon markets and some of your 
priorities for the policy in your testimony. Currently, many 
private carbon market offerings have minimum acreage 
requirements, indicating that this solution will benefit large-
scale operations at the expense of small, diversified 
operations, which I find concerning. The minimum acreage 
requirements could have serious implications for consolidation 
in the agriculture industry, making it even more difficult for 
middle- and small-scale farms to survive.
    How important is it that all farmers be able to participate 
in carbon markets, and do you think that there are specific 
steps that Congress and USDA can advance to ensure that farmers 
of color and small, mid-size diversified and beginning farmers 
can participate in and be rewarded for implementing climate 
stewardship practices?
    Mr. Brown. Thank you, Representative Adams, and yes, that 
is certainly a major concern of mine as well.
    It does not matter the size and scale of farms. They should 
be rewarded based on their practices and their outcomes. Small 
farms, in my opinion, have the ability to produce greater 
outcomes. They should be rewarded accordingly. I would urge 
that this Committee looks to ensure that these small farms have 
the ability to be rewarded for what they are actually doing, 
and that you make sure that any carbon market, the vast 
majority of the income that can be had from selling carbon 
credits goes back to the farmer themselves.
    Ms. Adams. Thank you. I think I am out of time, so, Mr. 
Chairman, I will yield back.
    The Chairman. Thank you so much. That was very informative. 
Thank you, Congresslady Adams.
    And now, I will recognize, for 5 minutes, Congressman 
DesJarlais of Tennessee.
    Mr. DesJarlais. Thank you, Mr. Chairman.
    The Chairman. Five minutes.
    Mr. DesJarlais. I thank all of our witnesses for appearing 
today. A special shoutout to Mr. Duvall from all the fine folks 
at Tennessee Farm Bureau. As you know, we have the largest farm 
bureau in the nation right in our district, and we are proud of 
the working relationship we have. So, I would like to get a 
question to you.
    But my first question is going to go to Mr. Shellenberger. 
It is timely because tomorrow we will be voting on H.R. 803, 
Protecting American Wilderness Act, and western wildfires are 
burning almost year-round now due to poor forest management. I 
think we can prevent these disasters from breaking out in the 
first place by doing a better job. We have over 80 million 
acres of Forest Service land that is considered high risk for 
severe fires, and we have overgrown forests that are in 
desperate need of both management and hazardous fuel 
reductions.
    Mr. Shellenberger, how do you view the current management 
of our nation's forests, and what should Forest Service and 
other land managers be doing better to encourage healthy 
forests?
    Mr. Shellenberger. Well, thank you very much for asking the 
question.
    We saw a very dramatic instance last fall in California, 
which is where I am based, where we saw a high intensity fire 
that was burning through the crowns of forests that were badly 
managed. When that fire arrived at a well-managed forest, the 
fire dropped down to the ground and became a low intensity 
fire. What that shows is that while climate change may be 
influencing forest fires, it is neither a necessary nor 
sufficient cause of high intensity fires, and the good news is 
that with better forest management, whether it is through 
selective harvesting, prescribed burns, or other methods that 
we already know how to use, we can prevent those kinds of high 
intensity fires from impacting our forests in the future.
    So, thank you for the question. Absolutely there is more we 
should be doing, and it needs to involve both the Federal 
Government and state governments, given that a significant 
amount of our forestlands are federally owned.
    Mr. DesJarlais. Thank you. Contrary to popular belief, as a 
doctor and as Republicans, we do believe in science and when 
discussing climate policy, it is important to note that the 
U.S. leads the world in reducing carbon emissions, and within 
10 years, nearly 90 percent of all emissions will come from 
outside the United States. But still in 2018, we on the 
Agriculture Committee put together one of the greenest farm 
bills ever, providing $6 billion a year to farmers, ranchers, 
and forest owners to implement soil health practices such as 
cover crops and no-till that can help draw down carbon and 
store it in the soil. These changes came after hundreds of 
hearings and listening sessions across the country where we 
heard directly from farmers.
    So, before I get to Mr. Duvall with a question, I hope, Mr. 
Chairman, that you can commit to this Committee holding a 
number of listening sessions with farmers and ranchers before 
we pass any new climate legislation.
    Mr. Duvall, can you talk about the importance of both 
having stakeholder involvement in the creation of any new 
programs, as well as any changes to current programs, and the 
need to ensure that these are voluntary and incentive-based 
programs for the farmers?
    Mr. Duvall. Well, the voluntary market-based incentive 
programs have been proven to work. Our farmers, if it is based 
on sound science and they know that it will improve their 
soils, improve their production to become more efficient, they 
will grab a hold of those new projects and move forward. 
Whether they are new or old ones, we need to make sure we 
continue to support them, and you are exactly right. You all 
supported them very well. We appreciate that. We just need to 
do something--Mr. Brown mentioned we need to do more education 
to the farmers of how they can use those programs. Our outreach 
as good as it should be, and it needs to be available to all 
sizes of farmers. We are all concerned that consolidation is 
going on. That is not what a general public wants. We want to 
be, there for the large farmer, but also make sure the small 
and middle-sized farmer is able to succeed and participate in 
all those programs.
    To talk about having private investment, of course the 
private companies out there, especially the food companies are 
marketing their products in a certain environmentally sensitive 
way, and if they are going to do that, they should be able to 
put some of the money behind where their thoughts are and be 
able to help support some of these expensive things like manure 
digesters and other things that farmers are having to put on 
their land to be able to help move forward in controlling our 
climate.
    Mr. DesJarlais. Thank you, Mr. Duvall.
    As we all know and was mentioned, nobody cares more about 
the land and the Earth than our farmers and our agriculture 
community, so we are standing ready to make things as good as 
we can.
    So, thank you all, and I yield back.
    The Chairman. Thank you very much, Congressman DesJarlais. 
To answer your question, you can rest assured that this 
Chairman of this Agriculture Committee will make sure that our 
farmers are at the center of our movement out of whatever 
legislation, whatever appropriations--that is the whole purpose 
of this Committee is for us and agriculture to have the inside 
pole position when it comes to climate change. My good friend, 
Richard Petty, told me and gave me that great advice when I 
asked him how he won so many races. He told me, ``Don't check 
the ones I have won. Look at the number of inside pole 
positions I have won.'' I didn't know what that meant at the 
time, but later I did.
    Mr. DesJarlais. Thank you, Mr. Chairman.
    The Chairman. Then I looked back in the mirror and I can 
see all the wrecks.
    Our farmers will definitely--that is why we are having this 
hearing, to make sure our farmers, our agriculture industry, 
has the inside pole position on our whole response to climate 
change.
    Now, I would like to recognize the distinguished lady from 
Virginia, my good friend, Ms. Spanberger.
    Ms. Spanberger. Thank you.
    The Chairman. Five minutes.
    Ms. Spanberger. Thank you, Mr. Chairman, and thank you to 
our witnesses. I came to Congress with a background in national 
security, and I know that climate change presents a national 
security threat. It also presents a threat to our health, 
economy, and the future of our nation. But agriculture, the 
work and purview of this Committee, can be and is part of the 
solution in addressing climate change.
    As you, sir, President Duvall, said in your testimony, U.S. 
farmers and ranchers have long been at the forefront of climate 
smart farming, and America's farmers and ranchers play a 
leading role in promoting soil health, conserving water, 
enhancing wildlife, efficiently using nutrients, and caring for 
their animals. I am so glad to see our Committee address 
climate change with the urgency that it requires, and I am glad 
that we have brought farmers to the table, though virtually 
only, today.
    I am glad we brought farmers to the table in discussing the 
role of agriculture in combating climate change. At times, 
farmers have been left out of the national conversation on 
climate change. When as we have heard today, farmers, 
foresters, and ranchers can and in so many cases are a part of 
the solution. We have heard from President Duvall and our 
colleague, Mr. Costa, about how the practices they have 
employed on their own farms have changed from the practices 
their parents and grandparents used, and Mr. Brown has spoken 
today and widely about his choice to employ new methods to make 
his farm profitable and increase his soil carbon more than six-
fold.
    Back home in Virginia, I have heard similar stories from 
crop and livestock producers in my district about how farming 
and conservation practices they employ are benefitting the 
environment, building more sustainable operations, and 
benefitting their bottom line. As Chair of the Conservation and 
Forestry Subcommittee, I have listened to farmers, not just 
back home in my district, but here in this room before our 
Subcommittee. And as a result, I worked to introduce H.R. 7393, 
Growing Climate Solutions Act last Congress with our colleague, 
Representative Bacon of Nebraska, and this bill has been 
endorsed by national farmer organizations, as well as large 
environmental and conservation groups, while garnering the 
support of corporations like McDonald's, Bayer, and Microsoft. 
This legislation has built a broad coalition because it 
empowers farmers to voluntarily employ or continue employing 
climate-friendly conservation practices, and it would help 
farmers unlock new revenue streams.
    Over the next month, I will be introducing a series of 
bills, including larger ones like (H.R. 2820) the Growing 
Climate Solutions Act, or simple, straightforward ones like 
H.R. 8057, Healthy Soil Resilient Farmers, and these bills 
would ensure that farmers are front and center in the 
conservation conversations that we are having, and that farmers 
have the tools to participate and benefit from voluntary 
programs as we all work together to tackle the climate crisis.
    Now, I would like to direct my question to President Duvall 
with the time remaining.
    Just yesterday, Mr. Duvall, you published a column in which 
you stressed the need to give farmers a voice at the table, 
particularly when it comes to changes in conservation programs. 
If the other Committee Members haven't read it, I recommend it 
to everyone.
    So, Mr. Duvall, could you expand a bit more for Committee 
Members on how is it we can make sure that the voices of 
farmers are heard when it comes to addressing climate change, 
and how we can prevent some of the mistakes we may have made in 
the past? Thank you.
    Mr. Duvall. Well, Congresswoman, you have made the first 
step today in asking me to come here and sit on this panel, 
along with the other panelists that have done such a tremendous 
job and have my respect.
    We need to be at the table during the discussions so that 
we can tell you how those policies that you are considering, 
how it is going to affect us on our land? How is it going to 
affect small, medium, and large farms? And as we do that, we 
can tell you what will work and what will not work. You also 
can help us make sure that the research dollars are there, find 
the new technology that needs it. Let's make sure that we don't 
tie our hands with the current technologies we have, because 
those technologies have allowed us to make the progress that we 
have made. And just like you said, as long as they are 
voluntary, they are market-based, and they are incentive-based, 
our farmers will latch on to it and do a good job with it.
    So, I think you are making the right steps. Just please, 
let us keep our seat at the table and we will make sure that 
you have all the information from the countryside, from our 
farmers, to make sure that you can make wise decisions that 
make not only farming successful, but also makes our rural 
communities resilient.
    Ms. Spanberger. Thank you very much, President Duvall, and 
to the other witnesses today, thank you so much for 
participating. Thank you for bringing your knowledge, and thank 
you for joining us. I hope that we will be able to welcome you 
here in person at some point in the future.
    Mr. Chairman, thank you for this hearing. I yield back.
    The Chairman. Thank you, Ms. Spanberger. I have to remember 
to put my light on there.
    Now, I will recognize, for 5 minutes, Mrs. Hartzler from 
Missouri. Oh, she's not on? Then we will go to Mrs. Hayes of 
Connecticut. You are recognized for 5 minutes.
    Mrs. Hayes. Thank you, Mr. Chairman, for holding this 
hearing, and thank you to all the witnesses who are here today. 
Can you hear me?
    The Chairman. Go ahead, Mrs. Hayes. You are recognized for 
5 minutes.
    Mrs. Hayes. Okay. Climate change is an important threat to 
Connecticut. From June 2016 through May 2017, Connecticut 
experienced its longest drought since 2000. At one point, more 
than 70 percent of the state was considered in extreme or 
severe drought. Simultaneously, the average temperature in 
Connecticut is continually rising. Since 1970, Connecticut has 
warmed by 8, compared with the national average increase of 
2.5 F. To compound these issues, more frequent extreme weather 
is already costing Connecticut huge amounts of money. Between 
2017 and 2019, Connecticut experienced two severe storms and 
two winter storms. The damages led to losses of at least $1 
billion. Small farmers in Connecticut are leading the charge in 
sustainable agricultural practices, but we cannot leave the 
health of the planet up to individual decisions.
    As the Members of this Agriculture Committee, it is our 
responsibility to ensure that the industry is providing clear 
solutions to address climate issues.
    My question today is for Mr. Brown. A report from the USDA 
recognized increased food insecurity as a risk posed by climate 
change. As a farmer who is practicing and teaching resiliency, 
can you explain how climate change could impact levels of food 
production, and ultimately increase global food insecurity if 
we do not act?
    Mr. Brown. Thank you.
    The way for Congress and ranchers to not only mitigate 
climate change by taking more carbon out of the atmosphere and 
putting it into the soil is to make our soils more resilient.
    In 2020, Burleigh County, North Dakota, where I ranch, was 
the second driest year ever recorded. Yet, even though that 
happened, we were still able to graze the same amount of 
livestock. We were still able to raise profitable cash crops 
because of the resiliency we had built into our soils, by 
taking massive amounts of carbon out of the atmosphere and 
putting it into our soils.
    The other thing that many of us who are practicing 
regenerative agriculture are doing, is that we are diversifying 
our farms and ranches. So many of our farms and ranches today 
are not diversified. They only grow one or two different cash 
crops. They only grow or raise one species of livestock. We 
need to diversify that, and by so doing, that is going to allow 
society to have the food security we need.
    Mrs. Hayes. Thank you. You are right. Clearly, it is 
essential that we preserve the resiliency of our agriculture 
sector if we have any hope of eliminating hunger in America, 
which we have seen literally in the last year grow to be blown 
to a much larger problem.
    Mr. Duvall, we all know that heat stress will likely cause 
the overhead costs of dairy farms to go up, while driving their 
production down. Many small farmers in my district, dairy 
farmers, already turn limited profits under this current 
situation. Can you provide some steps that Congress and the 
USDA can take to help small dairy farms as they prepare for 
climate change?
    Mr. Duvall. Well, of course, I think we have taken some 
huge steps already through Congress to help in the farm bill 
fix some of the problems we had around the risk management 
tools that we had built in there for the dairy farmers, and 
there has also been some private products that have been 
offered to them.
    But, we need to take a hard look at the Federal Milk 
Marketing Order system. We need to make sure that our farmers 
have an opportunity to speak to changes that are made in the 
Federal Milk Marketing Order system, and that each one of them 
have the opportunity to speak to that. So, we are, right now, 
continuing to do a study of our own, and we will be glad to 
share with you the results of that study as we finish it out on 
how we move forward and make it more profitable.
    We continue to see small dairies go out of business and 
more consolidation in dairy getting bigger.
    Now, this country--really, American agriculture was built 
on the back of small dairies all over this country when we were 
all real diversified, and it really is a shame to see these 
small dairies not survive anymore. We have to find a way that 
small, medium, and large dairies can survive in this 
environment, and to help them be financially stable enough to 
be able to take on the practices that, in some cases, are going 
to cost a lot of money to help us end climate change.
    Mrs. Hayes. Thank you, Mr. Duvall. I truly appreciate you 
saying that, because in my district in my State of Connecticut, 
small dairy farmers are really the backbone of our farming and 
agricultural industry, so I really appreciate you saying that, 
and for coming to this hearing because we cannot continue to 
have these circular conversations debating if climate change is 
real or if it is happening or what the impact is. We have 
measurable data that tells us all this information, and now we 
have a responsibility to act.
    Thank you, Mr. Chairman. With that, I yield back.
    The Chairman. Well, thank you, and also thank you, Mrs. 
Hayes, for the excellent job you are doing as the Chairwoman of 
our Subcommittee on Nutrition, Oversight, and Department 
Operations.
    And now, let me give an apology there. I got my paperwork 
mixed up and recognized two Democrats. Now, thank you for 
allowing me to represent and to recognize two Republicans. 
Thank you for your understanding.
    Next, we will have Mr. LaMalfa from California.
    Mr. LaMalfa. Thank you.
    The Chairman. Five minutes, sir.
    Mr. LaMalfa. Thank you, sir.
    Mr. Duvall, real quickly I wanted to touch on the concept 
with the carbon banks and the USDA, maybe through CCC, being a 
possible authority of establishing carbon banking. Has AFBF 
looked into whether the USDA can do this on its own authority, 
or would the Farm Bureau be joined with us in opposing any 
attempt to have that just be done by Executive actions, as 
opposed to running it through a Congressional process so this 
can be vetted, and that there are not winners and losers on how 
the carbon banks would work? Has Farm Bureau looked at that? 
What do you believe the position should be on that?
    Mr. Duvall. Yes, I haven't asked my staff if we were 
looking into the legality of it. I will tell you that we are 
concerned that if it is developed and financed through the CCC 
that the levels of CCC borrowing authority is not nearly high 
enough. We support raising that level to $68 billion. We think 
because of the economy and the increases over the years that it 
should be at that level instead of $30 billion. I have spoken 
to Secretary Vilsack about that certain issue, and he committed 
to me that he would not pay for it off the back of our title I 
program or our conservation programs, so I was delighted to 
hear that.
    But, we are interested in seeing, this is the place. 
Agriculture is the place. This is the Committee where we see 
the most cooperation between both sides of the aisle. You all 
always find a way to find ways to work together, and I hope 
that in this environment we can continue to do that, and I 
think I see that in the leadership of this Committee. And I 
would love to see the conversation through this Committee 
decide how that is going to be paid for and where it is going 
to come from. If we are going to put in modern day agriculture, 
we have to have modern day practices. It requires research 
dollars. It requires extension and education. It requires 
funding for new programs that we put out there if it has to do 
with climate. The funding has to follow those programs so that 
our farmers and ranchers can afford to do that.
    Mr. LaMalfa. Yes, sir, I hear you.
    Yes, I just don't want to see an authoritarian attitude 
come out of this, because it looks just a little bit ominous. 
What hasn't been talked about very much is an already difficult 
situation with ag profitability, and where are they going to 
find the profitability?
    We have the concept of diversification. Well, certain 
climates, certain soil types, certain water availabilities just 
don't lend themselves to change crops, and I experienced that 
in northern California. We have some of the best crops grown in 
Central California if they have the water supply not taken from 
them. That is the only place that many of these crops are grown 
anywhere in the world--or in our country, at least. We would 
have to import is part of the problem.
    Mr. Shellenberger, I appreciated your testimony and your 
way of talking about things in this conversation, as well as 
recognizing farmers are doing a pretty good job in this country 
in innovation and trying to keep up.
    We are hearing a lot of talk about the crisis of climate 
change, and what is your interpretation of where we are at, 
especially with how what agriculture might be driving in or 
helping with in this crisis as it keeps being presented ad 
nauseum, in my view, around here. Please bring that in on 
forestry, because my area is a part of the area that is burning 
so much. I believe strongly that it is from an overload of fuel 
in our western forests.
    Mr. Shellenberger. Yes, thank you for the question.
    I will make a couple of comments. I mean, I think the first 
is that I think it is a mistake to use climate as the single 
overriding measure of success with farming or anything else. I 
mean, we see that carbon emissions have been coming down in the 
same way that other air pollutants came down in the 1970s. It 
is actually quite extraordinary progress in the United States 
mostly due to the transition from coal to natural gas.
    In the case of farming, increased efficiency and 
productivity should be the goals, because those result in what 
we call land sparing. It results in less land being used, less 
fertilizer, less runoff, less air pollution, less land farmed. 
I mean, there is less air pollution from farm machinery. So, I 
think it is a mistake to organize strictly around carbon. I 
think, in many ways, you want to organize more around land use 
efficiency or input efficiency.
    On the question of emergency crisis, those aren't words 
that I think are very helpful. We saw some activists encourage 
panic. That is not something we should ever encourage, since 
panic means unthinking behavior. Climate change is a long-term 
process. It is not something that you solve with one piece of 
legislation or that one generation will solve. It is something 
that we are going to be managing for a long time.
    And so, when it comes to forests, I would love to see more 
money spent on forest management. I think that is a much more 
higher priority, since we just have a lot of fuel built up in 
western forests that led to the severe fires that we saw last 
fall.
    Mr. LaMalfa. All right, I appreciate that. The crisis 
really seems to be driven by a lack of forest management, and 
the overload we have per acre of forest fuels, and we don't 
seem to be able to get much cooperation. I appreciate that your 
points on grazing could be part of that tool in your comments, 
and grazing is always under attack in western states as part of 
that tool. Great points as well on the more you cause some of 
these effects, it takes more land to grow the same amount of 
crops, and with that, more water that we are in short supply in 
California as well.
    So, Mr. Shellenberger, I would love to have you come up to 
my ranch in northern California some time and talk about this 
some more. Thank you.
    Mr. Shellenberger. Thank you.
    The Chairman. Thank you, and now I recognize Mr. Allen, for 
5 minutes, from Georgia.
    Mr. Allen. Thank you, Mr. Chairman, and I want to wish 
everyone a good afternoon. Welcome to our panelists. I am just 
delighted that we are having a hearing. For almost exactly a 
year, this Committee has, for all intents and purposes, been 
not operational. Since March 4, 2020, we have had one single 
full Committee hearing, and in my opinion, this is inexcusable, 
and I believe Chairman Scott and Ranking Member Thompson share 
that opinion with me. I am looking forward to returning to 
regular order quickly, and Chairman Scott, I appreciate again 
your insistence on getting this ball rolling very quickly.
    We have a lot of important business and oversight to attend 
to. Particularly, we begin the preliminary first steps of 
writing a new farm bill. It is hard to believe that that is 
coming up so quickly.
    Zippy, as you already pointed out, farmers are not the 
problem when it comes to greenhouse emissions, with the ag 
industry only producing about ten percent of U.S. greenhouse 
gas emissions. We are kind of barking up the wrong tree with 
this hearing. Farmers are the best environmentalists in the 
world because they depend on the land for their livelihood.
    In the Book of Genesis, we are told that God gave us 
dominion over the Earth. All the challenges found in the ag 
industry come right out of Genesis 3:18. God created man and 
woman and he created them to tend the garden in which, again, 
God created.
    If we want zero net carbon emissions, there are a lot of 
ways to do it. One is obviously plant three trillion trees 
would be a start. But what the two sides of the aisle disagree 
over is not really climate change. We all want to be good 
stewards of the environment. What we disagree over is the power 
that should be given to the government. Climate change at its 
worst can be and is used by various actors as a Trojan horse by 
which they gain the power to regulate and have total oversight 
over every industry and citizen in this country. There is room 
for both educated insight and common sense in this debate, but 
right now I feel that we have too many absurd policy proposals 
coming from the far-left alarmists.
    One fact from the Earth Observatory at NASA on the actual 
tilt to the Earth suggests that the debate on how much this has 
caused is still ongoing. In fact, that piece of article says 
that as the actual tilt increases, the seasonal contrast 
increases so that winters are colder and summers are warmer in 
both hemispheres. Today, the Earth's axis is tilted 23.5 from 
the plane of its orbit around the sun. But, this tilt changes. 
During a cycle that averages about 40,000 years--again, I think 
I heard someone say this is a long-term issue, the tilt of the 
axis varies between 22.1 and 24.5. Because this tilt changes, 
the seasons as we know them can become exaggerated.
    And Zippy, I will start off with you. I think you and I--of 
course, I don't believe anyone has claimed that they are in 
charge of that tilt. Zippy, I think you and I know who is in 
charge of the tilt and who created it. But my first question to 
you is what is the greatest environmental challenge that our 
agriculture industry faces?
    Mr. Duvall. What is the biggest environmental challenge?
    Mr. Allen. Yes, sir.
    Mr. Duvall. Well, I can tell you what the biggest challenge 
is to agriculture. The biggest challenge to agriculture, 
biggest limiting factor of agriculture is labor. But that 
doesn't have anything to do with the climate.
    Mr. Allen. Right.
    Mr. Duvall. I think the biggest limiting factor is our 
outreach and our communication. We need to make sure that we 
continue to tell farmers, because we do not have every piece of 
ground with cover crop on it. We do not use no-till on every 
piece of ground. But we need to continue to talk about what 
that does for us in the future, and we need to educate people 
and move them toward that. But it takes partners to do that. It 
takes money to do that, and of course, the programs that we 
have had have helped us, but we need to continue to move 
forward in that direction to put those practices on the ground.
    Another one of the limiting factors is the amount of 
research dollars that is being spent on these issues. I keep 
hammering on that because it is important. Research has kept us 
on the cutting edge of agriculture. A lot of times American 
agriculture gets downplayed as the bad guy, where agriculture 
in the rest of the world represents 25 to 35 percent of the 
greenhouse gases, we only represent ten percent. We are the 
leaders. Everyone should be following what we are doing in our 
country, and we ought to be accelerating through research 
monies and new projects to put on the ground and encouraging 
people to do it. Partners, research, and moving forward.
    Mr. Allen. Well, thanks Zippy, and I am out of time, and I 
yield back, Mr. Chairman.
    The Chairman. Thank you very much, Congressman Allen.
    And now, I recognize the gentleman from Illinois, Mr. Rush, 
for 5 minutes.
    Mr. Rush. I want to thank you, Mr. Chairman. Mr. Chairman, 
I was born on a farm, and as the son and grandson of two 
Georgia farmers, I am very excited about being on the 
Agriculture Committee, and I am excited about this hearing, and 
I want to commend both you and the Ranking Member for 
conducting this hearing.
    My question to you, directed, rather, to Mr. Duvall.
    Mr. Duvall, according to Feeding America, before the COVID-
19 pandemic, more than 35 million people struggled with hunger 
in the U.S., including more than ten million children. The 
coronavirus pandemic has made this situation worse, and we know 
that climate change will only further exacerbate the problem. 
Innovations in food production can enable growers to produce 
higher yields with lower inputs and help crops sustain the 
environmental stressors, and that will likely get worse during 
the climate change. New technologies can also help address the 
lack of fresh fruits and vegetables and food deserts, while 
among other things, cutting down on food waste.
    Mr. Duvall, how can we accelerate the development of new 
technologies to prepare for a changing environment, the growing 
problem of hunger? How can we assure that these technological 
breakthroughs are widely shared to benefit socially 
disadvantaged farmers and ranchers and urban communities who 
have historically been unable to access nutritious offerings?
    Mr. Duvall. Yes, sir, thank you for the question, and you 
are exactly right. The technologies that we have had at our 
fingertips have helped us improve our production by three-fold 
in the last decade.
    So, what can you do to help us? We need to streamline the 
regulatory system. When these technologies come forward, let's 
streamline the process to be able to get them approved and get 
them out on the farms to help us do that. We can do things, put 
crops in the ground that use less water. We can grow vegetables 
that have more nutritional value. If all these technologies are 
streamlined and instead of it taking 5 to 10 years, cut it back 
to a year, year and a half and get it out on the farms so that 
we can grow the crops, be more efficient, and keep the price 
down, because the way we can produce in America, there is no 
reason for anyone in America to be hungry. Farmers don't want 
that. We want to do the best job we can. We want to keep the 
cost of food reasonable so everybody can have access to it. And 
we appreciate the work that Congress did with us and Feeding 
America through USDA to deliver. When the market changed after 
COVID hit, you helped us deliver food boxes to families and 
helped our farmers change the way they marketed their food. So, 
we are very appreciative of those programs. But streamlining 
regulatory agencies to where we can get those products out to 
the farm quicker.
    Mr. Rush. Thank you, Mr. Duvall, for that fine answer.
    Mr. Cantore, in your testimony you mentioned how, and I 
quote, ``Children are being diagnosed with increasing 
respiratory illnesses due to a more hostile atmosphere.'' We 
know that Black and Brown children already tend to have a 
higher risk of respiratory illnesses as a result of poor air 
quality. As environmental conditions continue to change, what 
impact do you anticipate that they will have on an already 
vulnerable population?
    Mr. Cantore. Thank you, Congressman Rush, for the question.
    When you have these high air quality days, we have already 
have tools out there at our disposal to keep people inside as 
much as possible, but sometimes that isn't possible, and they 
have to go outside. Things like asthma are certainly becoming 
more prevalent with children and adults because there are so 
many pollutants that are just trapped in the air, and the 
longer we have these heatwaves--and they are popping up 
everywhere. Nobody is unprivy to this. You are going to have 
these pollutants just trapped and trapped in the air. Nothing 
is there to mix them off.
    In addition to what we are watching with weather, air 
quality issues, even though it is not something we see coming 
down at us, it is just as important to watch. So, these are 
expected to increase in the future, sir.
    Mr. Rush. I want to thank you, Mr. Chairman, and I yield 
back the balance of my time.
    The Chairman. Thank you, Mr. Rush.
    And now, I recognize Mr. Kelly of Mississippi for 5 
minutes.
    Mr. Kelly. Thank you, Mr. Chairman. I ask for unanimous 
consent that I get at least 25 minutes to ask my questions, 
because there is so much in this, and I thank you for having 
this important hearing. I am joking about the 25 minutes.
    But one of the things I want to talk about is I want to 
make sure that we are focusing on results, and not resources or 
on one solution. Many times, we ignore results because once we 
get invested in our solution or one way, we ignore new 
technology or new solutions. And so, when we are talking about 
zero emissions--I know Zippy Duvall talked about many farmers 
now have zero emissions or net zero emissions, and I think that 
is important. And going back to the cover crops and doing that 
to enrich the soil, you have rice as Mr. Crawford brought up, 
and I just got off a call with USA Rice, and talking about the 
cover crops literally being ducks to flood those areas.
    But in my area, we have many different types of crops, and 
so I am not sure that they are the same cover and I want to 
make sure we do the right research to get those. Whether that 
be peanuts or cattle or sweet potatoes or poultry.
    And so, Zippy, can you address any crops that may be a one 
cover crop is not a--one solution is not--does not fit all, or 
any specific crops which may have a different cover program to 
make sure our soils are preserved? Can you address that, Mr. 
Duvall?
    Mr. Duvall. So, of course, I think all of us know trees are 
the best way to sequester carbon. And then a diverse landscape 
of different crops in different regions would be the next best 
step. But there is tremendous work we do in the animal area. 
There are feed additives, and I was asked earlier what can we 
do to help it along? There are feed additives the FDA--they 
consider those as drugs. They need to be considered as feed so 
that we can get those additives approved and get them out on 
the farm to lower the greenhouse gases that are coming from our 
animals.
    And, those are some of the suggestions I would make.
    Mr. Kelly. Thank you very much, you know Mike McCormick at 
Mississippi Farm Bureau and you, Mr. Duvall, have been such 
great friends and great resources. I just hope before we do a 
one size solution fits all, that we talk to our Farm Bureaus or 
other organizations across our nation that represent all of our 
farmers, not just certain areas, because regions are different.
    The other thing, Mr. Duvall, how effective with getting 
rural broadband to our farmers to have access and would that be 
helpful to them being able to have the technology and the 
information and education to farm better for our environment?
    Mr. Duvall. I talked a little bit earlier about broadband 
being part of that building on our infrastructure, and today, 
broadband is not a luxury. It is a necessity. Whether it be 
education, healthcare, and taking advantage of technologies 
that are coming down the pipe that farmers can use to be more 
efficient and more climate friendly. So, it is absolutely 
necessary that we get those maps right, the Federal dollars 
that you all are so kind to put out there to try to fill that 
gap between urban and rural America, that those dollars go to 
the correct places, because a lot of places those maps aren't 
right. I struggle here with it in my house, and I am only 70 
miles from Atlanta. So, we have to do this.
    If you think about electrification back in the 1930s and 
how important that was to all Americans, broadband is no 
different. It has the same importance today that 
electrification had back then, and we have to find a solution. 
We found a solution to that one. We can find a solution to this 
one.
    Mr. Kelly. Thank you again, Mr. Duvall. I want to go back 
to Ms. Adams' point. I have many 1890 universities that I 
represent, HBCU, the many agricultural colleges, which includes 
Mississippi State University, which is not an 1890s college, 
but also an agriculture college. And I just think it is so 
important that we use research dollars to allow these 
universities to look at all these individual areas that I am 
talking about in crops and specific regions, because nobody is 
better situated to talk about specific regions.
    I am running real close on time, and the final comment I 
will make is, number one, invest in research and our 1890s 
universities and other universities, agriculture universities, 
and the second is we really need to get our State Department 
engaged in foreign policy that deals with nations that are 
either too poor or either ignore the environmental consequences 
and climate consequences of their nation. We need to engage 
them and make them part of our farm policy, whether it be 
through trade or other initiatives with our foreign policy.
    And with that, Mr. Chairman, I yield back.
    The Chairman. Yes, thank you very much, Mr. Kelly, and 
thank you for emphasizing our 1890s and the fine work you did 
with me and the Committee. What a great bipartisan effort in 
getting that $80 million down to those schools. I always lift 
that up as one of our shining bipartisan moments.
    And now, I would like to recognize the lady from Maine, Ms. 
Pingree, for 5 minutes.
    Ms. Pingree. Thank you very much, Mr. Chairman. Thank you 
so much for hosting this hearing and making it our first 
hearing. I think it really has been very interesting and 
informational, and I really appreciate that we have a lot more 
agreement than we often think that we do, and many of the 
topics that we have brought have shown our similar thoughts.
    I won't get a chance to ask everyone a question, but I do 
want to thank all the presenters. You really have given us such 
a great cross section, weather professionals to the importance 
of the cooperative extension service, the farmers' perspective, 
and Zippy, I really appreciate--I would like to have a meeting 
with you. It was a long time ago because we can't have a 
meeting anymore, but the work you have done with the Food and 
Agriculture Climate Alliance is really a great way to bring all 
the commodity groups and the farmers thinking together. I think 
that has really advanced a lot of our thinking on this. So, 
thank you so much on that.
    I have worked on this topic for a long time. I care deeply 
about it, and I encourage many of you to sign on to my piece of 
legislation, (H.R. 2803) the Agriculture Resilience Act. I 
think there are a lot of things we agree on that you all have 
been talking about on both sides of the aisle: research, soil 
health, viability for our farms, pasture-based livestock, food 
loss and waste, which is a big topic that our cooperative 
extension service mentioned. So, there really are a lot of ways 
that are farmer-driven that we can work on this.
    I want to try my first question on Mr. Brown. Thank you so 
much for really representing the point of view of what it takes 
for a farmer to make this transition. I want you to know, I am 
longtime fan of yours here. I have your book. If you were in 
the same room, I would ask you to sign it and I would give it 
to one of my favorite farmers, because I really enjoyed reading 
it. And I also want to thank you for giving a shoutout to H.R. 
2859, the PRIME Act. We are not talking about that today, but 
that really addresses the importance of having more 
infrastructure available to farmers and farmers who want to 
sell directly to consumers. There is a real dearth of 
slaughtering capability in our country, particularly for small 
and medium-sized farmers. So, I appreciate that you brought 
that up.
    You have gotten such a good explanation here to people 
about the work that you have done. But I know for a lot of 
farmers, it is very hard to make this transition. You have 
invested a lot, farmers have in the way they do things. Maybe 
it is generational. So, making this shift is a big leap, and I 
know you do a lot with talking to farmers about how you made 
the transition. What do you think we need to do to help support 
farmers in those transitions through the programs that we have, 
or other things that we could be doing more of?
    Mr. Brown. Thank you. I would be happy to sign a copy of my 
book for you anytime.
    The number one thing that is needed--and Mr. Duvall touched 
on this--is education. You don't know what you don't know. I 
owe a debt of gratitude to NRCS. There are many good people who 
work for that agency. They are moving in the right direction, 
but they need to be given the opportunity to educate farmers 
and ranchers. We need to really refocus conservation programs 
to maximize the adoption of these regenerative principles.
    Everyone here agrees that these principles work. Some say--
have said well, these principles--cover crops may not work in 
my area. Well, they missed the principle of context. You have 
to grow the species that work in your area. Farmers and 
ranchers are not going to know that intuitively. Okay? We have 
to use programs, use agencies like NRCS, the extension service, 
to educate farmers and ranchers. And I think it is important to 
note that by doing so, farmers and ranchers are able to 
significantly decrease their inputs. I can't say that enough. 
For instance, look at corn today. The average cost to produce a 
bushel of corn is near $5, yet I know many regenerative farmers 
who are doing it for less than $2 an acre because they are 
educated and have the information that it takes in order to cut 
those input costs.
    So, thank you for the work you are doing. We certainly 
appreciate it.
    Ms. Pingree. Thank you. I don't have much time left, but 
let me give it to Zippy if he wants to talk at all about the 
food and agriculture work that you have been doing, and just 
how that has brought so many different commodity groups and 
farmers together to talk about these things?
    Mr. Duvall. If you look at the Food and Ag Climate 
Alliance, it is a historic alliance. Never before have these 
organizations that think differently come together and agreed 
on three principles and put forth 40 recommendations. We are 
very proud of that work. We hope that people on the Hill as 
yourself, Congresswoman, that you will use those 
recommendations to help go forward and set policies.
    But it was not an easy feat, and none of us knew that we 
could make it happen. But when I sat down across the table from 
environmental advocates, people's eyebrows kind of went up. But 
we were able to do that because what we discovered is what we 
all want is thriving communities, successful farming, providing 
a great environment for our families, livestock, and the 
wildlife. We all want the same thing. We just have different 
ideas of how to get there. It is kind of like pitting 
conventional farming against organic farming. There is room in 
the marketplace for all of it, but we surely don't need to be 
throwing each other under the bus. We need to be working 
together to provide it for the people that want it, and provide 
a good environment for us all to live in.
    Ms. Pingree. Thank you. I have gone way over my time, but 
thanks for the work you do for farmers. And to all the 
witnesses, thanks so much.
    Mr. Duvall. Thank you.
    The Chairman. Thank you, Ms. Pingree, and now, I recognize 
Mr. Bacon of Nebraska.
    Mr. Bacon. Thank you, Mr. Chairman.
    The Chairman. Five minutes.
    Mr. Bacon. Thank you, Mr. Chairman, and it is such a joy to 
be part of the Agriculture Committee.
    Agriculture plays such an important role in Nebraska. It is 
the primary industry. It is the backbone of our economy, and 
even in Omaha, in the district I represent, agribusiness is the 
core.
    I just want to make a brief comment, and then I got two 
questions. I just want to start off by saying conservative 
climate solutions work. I mean, just look at the energy sector. 
Over recent years, we have become the largest energy producer 
in the world. We have become energy independent for the first 
time since the 1950s. Just think about that, 70 years ago 
roughly. We are exporting energy now. We are helping out our 
allies in the Baltics gain energy independence from Russia. We 
have done all of this while cutting emissions more than the 
next 12 countries combined. I think that is an incredible 
accomplishment. From 2005 to 2019, we reduced carbon emissions 
by 33 percent, and we did this not by punishing people. We did 
it by incentivizing behavior. We also did it by incentivizing 
technology and innovation, and that is what we should continue 
doing.
    So, my first question goes to Mr. Duvall. We know farmers 
are already making many positive changes, and we are already 
seeing the results. So, my question is should we implement 
policies for our farmers and ranchers to help them make more 
money when they implement sustainable agriculture practices? In 
other words, should we be focusing on incentives more so than 
the punishments? Mr. Duvall?
    Mr. Duvall. The heavy hand of any one network, even 
sometimes when you think about our children, and when you make 
it market-based, voluntary, incentive programs and prove to our 
farmers that it has a science-base and it is going to provide 
that kind of outcome, they are going to take advantage of that 
program that you put out there. So, it is vitally important 
that we make voluntary, market incentive-based programs as we 
move forward. And we look forward to having that discussion 
about what that looks like, and making sure that it fits all 
size farmers. That is crucially important to us, because we 
want to make sure--a lot of people look at American farmers and 
say you represent the large farmers. We represent large, 
medium, and small. We are always there to have their back, and 
we look forward to working with you to find those solutions.
    Mr. Bacon. Well, we look forward to working with you, too, 
on this because this is the right way to go forward.
    Conversely, I just want to get your input. What happens if 
we put a carbon tax on our farmers, such as fuel and energy? 
What kind of impact is that going to have on a farmer's top 
line and margins?
    Mr. Duvall. Inputs are one of the biggest expenses that we 
have, and when you start taxing that, the profits in 
agriculture are so razor-thin now, that is why people become 
bigger, because the margins are thinner and thinner, and you 
got to do more and more to be able to make a living out there. 
So, if you put a carbon tax on it, it is just going to make it 
more expensive, and it is going to be hard for people to make a 
living.
    I want to go back and touch on one thing. We want to be 
energy independent. This country turned to American agriculture 
to be part of that solution. We built a whole infrastructure 
around renewable fuels, and we need not forget that farmers 
answered that call, that infrastructure is valuable to our 
rural communities, and it is valuable to our farmers to market 
their grain. I think that is the important thing we need to 
think about.
    Mr. Bacon. Well, thank you, Mr. Duvall. I totally agree.
    Mr. Shellenberger, how do we best balance implementing 
climate solutions that don't raise the costs of food? For 
example, if we do a lot of different measures, it could make 
our beef, our pork, vegetables and fruits much more expensive, 
and in the end, that affects the poorest amongst us. Those who 
are most food-insecure will find themselves even more food-
insecure. So, how do we balance this while we are protecting 
the most needy amongst us, in your view?
    Mr. Shellenberger. Well, thank you for the question.
    I think there is a real serious misunderstanding, because 
there is this idea that if you make things more expensive, that 
that is better for the natural environment, and that is just 
not the historical pattern. We find that by making food 
production and energy production more efficient, it also 
becomes better for the environment. So, you just use less land 
when farming, that is also part of reducing costs. Similarly, 
you mentioned before that carbon emissions peaked and have been 
declining since 2008. Very significantly, that occurred not by 
making energy expensive, but by making energy more abundant and 
cheaper, particularly natural gas with the Shale revolution. 
So, I think that that should be the orientation. Anything that 
seeks to make energy more expensive is obviously regressive. I 
think Democrats and progressives and every other context would 
oppose those things, just as we have tended to oppose taxes on 
food. So, I think the orientation should be heavily towards 
efficiency and productivity.
    Mr. Bacon. Thank you.
    Mr. Shellenberger. When we are looking at solutions, if 
they start to make energy and food expensive, that would be a 
red flag, both for equity reasons, but also for environmental 
ones.
    Mr. Bacon. Okay. Thank you very much, and Mr. Chairman, I 
yield back.
    The Chairman. Thank you. Thank you, Mr. Bacon, and now, I 
recognize the gentlelady from New Hampshire, my good friend, 
Ms. Kuster.
    Ms. Kuster. Thank you, Mr. Chairman, and thank you for your 
leadership and your decision to hold this landmark hearing.
    I want to begin by noting the dedication and commitment of 
farmers and foresters in New Hampshire to reducing emissions 
and mitigating climate change on their land. they know, perhaps 
better than any sector of our economy, how climate change 
threatens their livelihoods, and we are seeing warning signs 
already.
    The USDA Hubbard Brook Experimental Forest in my district 
has provided top notch analysis through their work studying New 
Hampshire's climate for the past half century. They found our 
average annual temperature has already risen a staggering 2.6. 
Rainfall has increased, often in condensed periods of heavy 
storms. Flooding has become more common, and as the Co-Chair of 
the bipartisan Ski Task Force, I want to point out that we have 
10 fewer days of snow on the ground. Climate change shortens 
our maple sugaring season, complicates the growing season for 
our farmers, and brings more invasive species to our forests, 
and that is just the tip of the iceberg.
    Our farmers and foresters have enough uncertainty to deal 
with running their business. Climate change is exacerbating 
those challenges.
    So, one such effort is President Biden's 30 by 30 
Initiative, conserving 30 percent of our land and water by the 
year 2030. Our conservation heritage runs deep in the Granite 
State, and more needs to be done to ensure that private farmers 
and forestland will continue to serve this purpose as land 
prices rise.
    So, my first question is for Zippy Duvall. I know the Farm 
Bureau is proud to note over 100 million acres of farmland are 
now in conservation programs with the Natural Resources 
Conservation Service, including 42 percent of agricultural land 
in New Hampshire. Could you speak about the importance of 
conservation from the Farm Bureau's perspective?
    Mr. Duvall. Yes, ma'am, and thank you for the question. Of 
course, those conservation programs putting land into 
conservation with USDA has been vitally important. We put the 
least valuable, less productive lands in that area. So, that is 
extremely important. But we also have a huge moral 
responsibility to recognize that as population grows, we have 
to feed them. We have to feed them. So, we are interested in 
continuing those programs that you speak of, but we also want 
to see working land programs that helps us be more productive 
there and do an even better job for the climate in those areas, 
and that is going to require research and development dollars, 
and extension and education, and broadband. It is just 
crucially important. But those programs are very important, and 
we are very proud to be part of that.
    Ms. Kuster. Great, thank you. I 100% agree with you on the 
broadband.
    Ms. Knox, I appreciate hearing your initiatives. Your 
counterparts at the cooperative extension at the University of 
New Hampshire have been incredible partners to me and the 
farmers and foresters in my district. You mentioned the need 
for more research, as Zippy just did, to help foresters adapt 
to new climate conditions, as well as best practices for making 
working forests the most effective carbon sinks possible. From 
your perspective, how can Congress be most helpful in fostering 
this kind of research?
    Ms. Knox. I think that USDA already has a number of 
programs that are really geared towards improving research in 
forestry. We certainly need to see more attention paid to that, 
and we need to work with extension agents to identify not only 
the research that's there, but also how to talk to landowners 
about planting more land. You have to pick the right trees, you 
have to pick the right location, and so, it is not just a 
matter of the research on the trees themselves, but 
communicating how the landowners can use that. The same thing 
works with what Zippy said about technology. If you have 
information but you don't have a way to get that to the 
farmers, then you have really lost a critical step, and that is 
really where extension falls in, because they talk between--
they are translators, essentially, between the scientists and 
the farmers. And it works both ways, because the scientists 
also need to hear from farmers, because they need to know what 
is important to the farmers.
    Ms. Kuster. And one last quick question. You talked about 
the overuse of fertilizers contributing to carbon emissions. 
Does your cooperative extension encourage farmers to adopt 
strategies like planting trees and perennial grass to reduce 
fertilizer usage and runoff?
    Ms. Knox. They provide a number of different solutions. Of 
course, in farming one solution does not fit everybody. But the 
extension agents use a variety of techniques to talk about what 
is the most responsible way to deal with the farm on a case-by-
case basis. So, they are really boots on the ground to look at 
what is happening for individual farmers.
    But yes, they do talk about that quite a bit.
    Ms. Kuster. Great. Well, thank you so much for being with 
us. My time is up, and I yield back.
    The Chairman. Thank you, Ms. Kuster, and now, I recognize 
for 5 minutes Mr. Johnson from South Dakota.
    Mr. Johnson. Thank you, Mr. Chairman. I appreciate that.
    I have a couple of things. I have enjoyed the comments a 
number of my colleagues have made, like Mr. Bacon talking about 
America reducing its carbon footprint by 33 percent from 2005 
to 2019 he said. That is incredible progress. And then I liked 
Mr. Scott, Mr. Crawford, and others talking about the role that 
American ag producers have had in that environmental 
stewardship, and I think it is fantastic. I am just thinking 
about the impact that the farm bill, this incredible piece of 
legislation that incentivizes and encourages good stewardship, 
has had on clean water. You think about the impact, 19.3 
million acres where we have had increased soil habitat, we have 
had better soil health and habitat. There are a lot of success 
stories to be told here in agriculture. And of course, I was 
glad to hear Mr. Duvall talk about the role of technology. I 
don't want to be a home state braggart, but of course, I do 
want to recognize South Dakota State University and their first 
in the nation 4 year degree in precision agriculture, because I 
think that plays a role in good stewardship as well.
    But Mr. Duvall, I want to dive in a little bit deeper into 
a conversation that you noted that you and Secretary Vilsack 
had. We have been talking about a carbon bank, and there are a 
lot of questions I have about a carbon bank. You mentioned that 
the Secretary committed that it would not, in any way, come at 
the expense of title I programs. Can you tell us a little bit 
more what that conversation was like?
    Mr. Duvall. Well, I think it was just out of rumors that I 
was hearing and it was referenced earlier--in an earlier 
question. So, I just point blank asked the Secretary. He was 
very--he didn't have to think about it at all. He said, ``I 
understand how important the farm bill title I, all the 
commodity programs are in conservation,'' and he says, ``I 
don't have any interest in shorting them anything by using 
monies from that area that would go into climate.'' Secretary 
Vilsack, did a great job in the past, going to do a great job 
in the future. We look forward to working with him, and I was 
real satisfied with his answers.
    Mr. Johnson. And so, did you get the sense--and I know you 
are part of an alliance that has spoken in favor of a carbon 
bank. I mean, is the CCC the mechanism that would be used, 
either in your understanding or what Secretary Vilsack relayed, 
to make these investments in a carbon bank?
    Mr. Duvall. Our conversation did not go that far to talk 
about whether or not the CCC was to be used to do that. I will 
tell you the historic alliance that I spoke of, we are 
interested in having that carbon bank and looking forward to 
having that set up. And of course, the fear that we get from 
the countryside of our farmers is what does that really look 
like, and is it going to be valuable enough to actually make 
that commitment? How many regulations are going to be around 
it, and who is really going to make the money out of it? Is it 
going to be an additional revenue stream to me on my farm to 
help me be more assertive of doing more practices that are 
climate friendly, or is someone in the middle going to make all 
that money? Of course, we do trust USDA more than we would some 
outside person handling it.
    Mr. Johnson. Well, and I am glad you mentioned that kind 
of--how does the money work thing, because hopefully you can 
educate me and some others about this. I mean, there are high 
transaction costs. I think a number of experts indicate that 
that could be a real concern with something like a carbon bank, 
and I think some estimates are that the highest recurring cost 
associated with carbon credits would account for 50 percent of 
the cost. Under that kind of analysis, only ten percent would 
actually get to the producer, and that doesn't seem like a very 
producer-focused mechanism in my mind. So, Mr. Duvall, give us 
some sense of what your understanding of those costs would be?
    Mr. Duvall. I think they still haven't been discovered yet, 
and I think that the biggest fear farmers have is they want to 
know before they buy into it or before they support that, and 
before we support it, we got to know what that carbon bank 
looks like, and we got to know what kind of return it is to our 
farmers. Because ten percent--I am like you. I am not sure that 
it is really a viable program. I don't think you will have a 
lot of people participate.
    Mr. Johnson. Sure. It looks like I am down to very little 
time, but perhaps maybe the Chairman can give you an indulgence 
of 1 more minute to answer my question. I mean, I do have 
concerns about a carbon bank and what exactly the Federal 
Government's role would be in it.
    I got to be honest with you, Zippy. I have loved working 
with you. Everybody in this Committee trusts you, and the Farm 
Bureau. You are good people. So, give me some sense of what 
analysis made you all comfortable getting on board with a 
carbon bank? I have questions on impact on land prices, impacts 
on market conditions, on private markets, on whether it should 
be performance-based or outcome-based. I mean, what got you to 
a point of comfort, because I am not there yet?
    Mr. Duvall. Well, I will admit to you, I am not totally 
comfortable yet, but I am ready to have the conversation what 
that looks like and how we develop that market. And someone 
really smarter than me is going to have to figure that out, and 
I am sure there are smart people out there. So, I am just as 
eager as you are to find out how this works, and what the--
because everybody wants to claim it as an alternative revenue 
stream to farmers. I want to know what that revenue stream 
looks like, and I want to know what procedure that carbon tax 
or carbon market is going to return back to the farmer. There 
may be a time in the future when we as an organization may not 
support that, but we have to have a conversation about what 
that looks like. And when we get those answers that you are 
asking for, we will be glad to share them with you.
    Mr. Johnson. Mr. Chairman, thank you for your indulgence. I 
would yield back the negative time I have.
    The Chairman. You are quite welcome, but I must admit and 
assure you that Zippy is indeed a very smart man.
    Thank you for that, and now Ms. Plaskett, you are now 
recognized for 5 minutes.
    Ms. Plaskett. Thank you so much. Thank you, Mr. Chairman.
    As the Subcommittee Chair of the Biotechnology, 
Horticulture, and Research Committee, I appreciate the 
Committee's focus on climate change and its impact on our 
farmers and ranchers. This is a topic I care deeply about, and 
one that my constituents are already facing.
    Early in the 116th Congress, the Biotechnology Subcommittee 
held a hearing on examining ways for farmers to increase 
resiliency and mitigate risks through research and extension. I 
am so glad we are continuing that discussion here today.
    I would like to direct my questions at Ms. Knox. In your 
testimony, you touched on the frequency of extreme weather 
events and how climate change can influence those events. This 
is something that is painfully familiar to my constituents in 
the U.S. Virgin Islands who experienced two major back-to-back 
hurricanes in 2017, and have faced periods of drought in years 
since. Specifically, your testimony touched on flash droughts 
as an area of focus for your research. Can you elaborate more 
on this phenomenon and why these droughts are so powerful to 
farmers and ranchers?
    Ms. Knox. Yes, ma'am, thank you for your question.
    Flash droughts is an area of huge concern right now in 
agriculture. Flash drought, if you don't know, is a drought 
that comes on very rapidly, and so because it is coming on 
rapidly, often with either high temperatures or a complete lack 
of rainfall, or maybe some of both, really accelerates stress 
on plants. And of course, plants need to have regular amounts 
of rainfall or irrigation water to survive. And so, when we 
have flash droughts, the plants can go from healthy and 
thriving to really stressed and sick plants in a very short 
time, sometimes even as much as a week. And so, our ability to 
identify those flash droughts is, of course, important because 
then it will tell the farmers they need to do something about 
it. But we also need to be able to plan for what can you do to 
help keep your plants alive during these times of flash 
drought. And so, you can use irrigation, you can grow different 
types of crops, you can do cover crops which keep more soil 
moisture available. But all of those are things that need to be 
looked at.
    Flash droughts, one of the projects we are working on right 
now looks at soil moisture and measuring soil moisture, because 
that is an important piece of information that farmers need to 
have, and yet, there is not a lot of really inexpensive pieces 
of equipment that people can use to do that. So, some of the 
projects I am working on right now are to identify some of 
these less expensive ways to monitor soil moisture, and provide 
that information to the farmers in a way that they can use it 
to put on just the right amount of water. They don't need to 
overwater, but they need to put on enough water to keep the 
plants alive.
    Ms. Plaskett. Thank you.
    What is the role of cooperative extension in helping our 
farmers and ranchers become more resilient, particularly for 
those who are small scale and limited resource producers?
    Ms. Knox. I think cooperative extension plays a really 
critical role because there is a lot of research that is out 
there, but it isn't necessarily getting to those small 
producers in a form that is useful to them. So, cooperative 
extension really serves as a way to translate some of that 
research into useful information. And I am a pragmatist, so I 
want to make sure that whatever information is provided is 
useful and is in the right format for those producers.
    And so, every situation is different. You have to go out in 
the fields, perhaps. A lot of extension agents spend 
significant amounts of time walking the fields with their 
farmers, and so they really know the needs of those particular 
farmers. And it could be big farmers or small farmers. But they 
need to be able to talk in such a way that the information that 
is provided by the scientists is useful, and they need to 
listen to the farmers and tell the scientists what they should 
be working on, because the scientists can't really work in a 
vacuum either.
    Ms. Plaskett. Okay, thank you.
    In the short time that I have left, can you say what 
additional research is needed to better understand how climate 
change will impact farmers and ranchers, and how USDA can help 
close those knowledge gaps?
    And after your answer, I yield back. Thank you, Mr. 
Chairman.
    Ms. Knox. Thank you.
    Some of the research that we don't really know very much 
about, we know that climate change is going to impact 
temperatures. We don't know really how well it is going to 
impact things like solar radiation or moisture balance in the 
soils, because those are secondary things, and they depend on a 
lot of other things that are not as easy to resolve, say, in 
climate models. For example, the cloud cover, which obviously 
controls the amount of sunlight. But sunlight is important to 
the growth of many crops, and if you have cloudy conditions, if 
you have a lot of rain or just cloudy conditions, then it is 
very difficult to plan how fast the crops are going to grow.
    And so, looking at some of the secondary variables that are 
really important for agriculture, which include things like 
soil temperature and humidity, and things like degree days and 
how fast they accumulate, cloudy conditions, are all important.
    Ms. Plaskett. Thank you very much. I yield back, Mr. 
Chairman. Thank you for the time.
    The Chairman. Of course. Thank you. Thank you very much.
    Now, we have had a call of votes. This is an important 
hearing. We have a wonderful panel, and we have Members that 
want to make sure they are recognized for questions. So, my 
excellent staff and I have worked out a procedure that we are 
going to do where we will keep our hearing going as some of our 
Members go. And as you go, remember, please, as soon as you 
come back, to make sure you contact the staff and let us know 
that you are back in position.
    Now, it has just been called, and let's see. Where is my--I 
had a list of--no, the--oh, here it is. Okay. These are the 
next five Democrats and Republicans who will be recognized, and 
the reason I am calling their names is hopefully they will be 
here and vote. Others who are further down can leave and then 
come back quickly.
    So, Mr. Baird, you are next. That is followed by Mrs. 
Bustos, and then Mr. Hagedorn, and then Mr. Carbajal, and then 
Ms. Craig and Mr. Cloud. That is six--one, two, three, four, 
five, six people at 5 minutes gives us a good half hour here 
now, and these six can go and hopefully some of you all who are 
leaving now whose names have not been called, you can leave and 
hurry back within the next 30 or 40 minutes, and we can keep it 
going. I think that is our strategy.
    Okay. Now, I assure you that everyone will be recognized. 
This is an extraordinarily important hearing, and we can work 
this out. So, those of you whose names I haven't called, please 
feel free to go. We are coordinating with the floor and they 
will allow you to vote as soon as you get there, so you can 
return. Thank you. Is that right? I see Anne here. Is--did I do 
all right, Anne? Okay. Anne says I did.
    Now, we will recognize Mr. Baird.
    Mr. Baird. Thank you, Mr. Chairman, and I really appreciate 
you and the Ranking Member having this very important hearing. 
It really gives a platform to highlight agriculture and its 
importance to providing practical solutions to this climate 
change. And so, it is extremely relevant, and I am so pleased 
to be a part of it.
    My first comment really goes to Mr. Brown, and it is just a 
comment, because I think it leads to my question to Mr. Duvall 
next. But, it is exciting to see the soil samples that you 
held, Mr. Brown, and the changes you made in that 20 year 
period, and the relevance of capturing carbon in the soil. The 
black color and the interaction of that carbon, and its 
importance in helping improve productivity. So, anybody that 
knows anything about soil, those two soil samples you held up 
were just very informative. And so, it looks to me like with 
the one slide you had, you were able to move in a 20 year 
period, 1993 to 2013, from one percent or less than one percent 
carbon in the soil, and went to a level of seven percent. So, 
it is exciting to see that we have and farmers and ranchers 
have already been incorporating things that help carbon 
capture, and I think that is important.
    So, now I need to get on to my question, and that really--
you alluded to it before, Mr. Duvall, but it has to do with the 
regulatory concerns for livestock feed. The development--and 
livestock has been a part of my life, really all my life. I 
grew up in west central Indiana. I went to Perdue, so animals 
and a Ph.D. in monogastric nutrition all contributed to my 
concern about livestock. And so, you mentioned greenhouse gases 
and the emissions associated with livestock, and so on.
    Feed additives have been shown to reduce methane levels 
produced by ruminants by as much as 30 percent. The addition of 
enzymes to chicken feed can also improve protein digestibility, 
which helps reduce nitrogen emissions from the manure. 
Probiotics help animal feed and improve the gut health of the 
animal. Not only do these additives increase the nutritional 
value of the feed and lower the cost of production for the 
farmers, but it ends up being a win/win situation because we 
can reduce greenhouse gas emissions.
    As you mentioned earlier, many of these innovative products 
lack a suitable regulatory product category, and they end up 
being involved as animal drugs rather than being a feed 
additive. And so, I am pleased to see that the Food and 
Agriculture Climate Alliance, FACA, that the Farm Bureau has 
founded identified the need to expedite and reduce this 
regulatory burden in regard to FDA feed additive approvals.
    So, having said that, I would like to give you the 
opportunity to comment on what you think we need to do to 
streamline those FDA approval processes, and if there are any 
incentives or rewards that we can use to help producers utilize 
this kind of technology? Mr. Duvall?
    Mr. Duvall. Congressman, I am a farmer and I am an animal 
agriculture farmer out there for 30 years, and also worked for 
my dad as a child for 20 other years before that. And now I 
have beef cattle, and this is my 34th year growing chickens. I 
will tell you that that environment is the first area that you 
can improve your farm more than anything. Animals eat grass, 
and grass sequesters carbon. So, it all works together and kind 
of plays off what Mr. Brown was saying.
    The regulatory system, and I will admit to you, I don't 
know that I can give you the recommendations, but I will sure 
seek my staff on it to give you some recommendations about that 
in writing afterwards. But we know that it is very cumbersome. 
It takes too long. These companies go out and develop these 
additives that are food additives that helps us do this, and 
they have put tremendous dollars into creating them, and then 
they have to sit on the shelf at FDA and the things that we use 
to grow plants, to head off pests and disease, they sit on the 
shelf and they are just grilled to death for years and years 
and years. And by the time they get to the field, a new one is 
already on the shelf waiting to be approved the next time. We 
shouldn't be that way. We have people to feed. We have 
Americans that are hungry. We need to keep food affordable. We 
need to be as efficient as we can, and the only way we can do 
that is to streamline that system so that we can have those 
innovations and research reach the farm quicker.
    Mr. Baird. Absolutely. Thank you for your comments.
    Any other witness would care to comment about that?
    The Chairman. Mr. Baird, your time is up.
    Now we will recognize Mrs. Bustos for 5 minutes.
    Mrs. Bustos. Thank you, Mr. Chairman.
    My question is for Mr. Brown. In your testimony, you 
mentioned the benefits of sustainable practices and how they 
can help sequester carbon, increase water capacity and 
absorption, build resilience, and mitigate risk. These themes 
are consistent with the goals of something that I wrote out of 
my office called the Rural Green Partnership.\5\ That is a 
framework of policies and principles that are geared toward 
getting rural America involved in the climate conversation, and 
making sure that we play a part in spurring economic growth in 
our part of the country.
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    \5\ Editor's note: the statement referred to is located on p. 383 
and is available at https://bustos.house.gov/bustos-announces-rural-
green-partnership-to-combat-climate-change-and-spur-economic-growth/.
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    So, as a Member of Congress who represents a district where 
ag is our main economic driver, and as Chair of one of the 
Subcommittees of this Committee, General Farm Commodities and 
Risk Management, these are all issues that are top-of-mind for 
me, because they are top-of-mind for the growers and producers 
that I am lucky enough to represent in northwestern and central 
Illinois.
    So, over the past few weeks, we have been hosting a series 
of roundtables, and in every single one of them, our growers 
and our producers are talking about how they are engaging in 
sustainable best practice like cover cropping, no-till farming. 
But they don't feel that the Federal incentives match up with 
the work that they are putting in on the farm.
    So, Mr. Brown, and then--I would like you to go first, and 
then maybe Mr. Duvall, if you have something to add. Here is my 
question for the two of you. Where do you see potential for 
increased Federal investment and incentives to help more 
farmers adopt these practices while also rewarding those who 
have already been active in this space? That is also something 
that we have gotten some questions on.
    Again, Mr. Brown, if you can go first, please?
    Mr. Brown. Thank you. Thank you for the work you are doing.
    Where it begins is, as I said before, in education. You 
don't know what you don't know. We need to educate farmers and 
ranchers as to these principles. We need to show them that by 
applying these principles, they can significantly not only 
mitigate climate change, but they can significantly lower their 
input costs and increase their profitability.
    We seem to get hung up here on production and yield in 
pounds, and yes, we need to feed America, but what most don't 
realize is that production increases as we use these 
regenerative practices. Also, not only does production 
increase, but the nutrient density of our foods increases 
significantly. And I think that has been totally overlooked. We 
want to help the underserved? Let's increase the nutrient 
density. The only way we can increase nutrient density of foods 
is through healthy soils on land-based produced foods.
    Take a look at the work that Dr. Stephan van Vliet is doing 
at Duke University Medical Center using a mass spectrometer to 
measure over 2,500 different phytonutrient compounds in food. 
He is doing work currently that is showing a significant 
difference between food grown in the current production model 
and food grown in the regenerative model. Farmers and ranchers 
need to learn about this, and then they need to be rewarded 
with an outcome-based for the principles that they produce--for 
the principles that they enact.
    We cannot keep going down this model where the only 
incentive is based on yield in pounds. It does no good if we 
are feeding our society cardboard. Take a look at the facts. We 
are spending twice as much on healthcare as we are on food. 
Now, I am all in favor of lowering the cost of food from the 
standpoint that--but we have to do it in a way that brings 
profitability back to the farm and ranch. I agree totally with 
Mr. Duvall on that. We have to increase profitability to the 
farms and ranches. He talked about margins being razor thin. 
Well, I am sorry. One of the reasons I don't accept any 
government programs or subsidies is because I can't--I have 
decent margins because I have been able to lower my input costs 
due to the fact that I have enacted these principles.
    It all goes back to education. Thank you for your question. 
Please, this Committee has the ability to make sure that we 
educate through NRCS, through extension, and through other 
means. Thank you.
    Mrs. Bustos. Very good. Mr. Duvall, I am going to pass on 
you answering any more, because I have 8 seconds left.
    And with that, Mr. Chairman, I yield back. Thank you so 
much. Thank you, Mr. Brown.
    Ms. Adams [presiding.] And thank you. I want to recognize 
now the gentleman from Minnesota, Mr. Hagedorn.
    Mr. Hagedorn. Thank you, Madam Chair. I appreciate it. It 
is good to be at the hearing today, and Mr. Shellenberger, I 
appreciated your presentation and the way it demonstrated that 
farmers in America are already doing things to be sustainable, 
and to manage their land properly. And in many instances, of 
course, we lead the world in all that.
    But I find it really difficult to have a hearing about the 
effects of so-called manmade climate change and what we need to 
do about it with agriculture, and not address the proposals 
that are out there that would change the energy sector in this 
country, and what that would do to sustainability of our 
farmers from generation to generation, and the profitability of 
our farmers and keeping the price of food affordable for the 
American people.
    Now, President Duvall, let me ask you. I am going to list a 
few programs here, and I would like you to let me know if the 
Farm Bureau affirmatively supports any of these energy policies 
that are proposed by the Democratic party at this time in one 
way or another, whether it is the President or Congress.
    So, obviously these are all like the Green New Deal. First 
of all, the cancellation of the Keystone Pipeline. I will read 
these out, and you just let me know if you support any of them.
    Cancellation of the Keystone Pipeline. Imposing a carbon 
tax. Obama's Clean Power Plan. A ban on fracking. Rejoining the 
Paris Accord. Imposing livestock ban. Enacting a cap and trade 
system or mandating the phaseout of the combustion engine at a 
certain point, and the end of gasoline and ethanol use as we 
know it today. Does the Farm Bureau support any of that?
    Mr. Duvall. No, sir, we do not support any of those.
    Mr. Hagedorn. And that is my point. If you are worried 
about farmers and sustainability, these are the types of 
policies that are going to dramatically drive up the cost of 
energy for agriculture, agribusinesses and make it darn near 
impossible for most of our providers to stay in business, and 
to produce affordable food and an array of products for our 
people. I mean, depending on the commodity prices and the cost 
of fuel, 30 to 40 percent of the cost of producing a bushel of 
corn can be energy.
    So, all these policies are very highly inflationary, and 
they are going to hurt our farmers.
    Now, Mr. Shellenberger, in a recent 60 Minutes 
interview,\6\ billionaire Bill Gates suggested that established 
nations like the United States should transition to eating 
fake, synthetic plant-based beef. And he even went on to say 
that government should force regulation of fake meat to force 
consumers to comply if they didn't like the taste, effectively.
---------------------------------------------------------------------------
    \6\ Editor's note: the interview referred to, Bill Gates: How the 
world can avoid a climate disaster, is retained in Committee file and 
is available at https://www.cbsnews.com/news/bill-gates-climate-change-
disaster-60-minutes-2021-02-14/.
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    Now, based upon your presentation, does Bill Gates or this 
type of recommendation, is that, based upon any accurate 
understanding of the U.S. beef industry?
    Mr. Shellenberger. Well, I can't be--I didn't see the 60 
Minutes interview, so I can't specifically comment on it, other 
than to just observe that it would be impossible for any 
government to mandate particular diets.
    Just about four percent of the population is vegetarian, 
and most vegetarians eat some form of meat during the year. My 
view is that we should continue to innovate for alternatives to 
meat production, but certainly not mandate it. And as I 
mentioned, the meat industry has done a very good job at 
reducing their impact on land, particularly the transition from 
pasture beef towards more conventional concentrated beef 
production has been astounding.
    So, yes, I mean, I support the innovation. I don't think we 
are going to mandate that.
    Mr. Hagedorn. Well, let me reclaim my time.
    There is plenty of opportunity for the Federal Government 
and Democrats in Congress to mandate. They are going to mandate 
all these things that have to do with energy and what kind of 
cars we can drive, or what kind of energy is produced. There is 
no reason to think that they couldn't come forward and try to 
mandate that we could no longer have livestock production in 
our country the way we have it, and that we would need to move 
towards plant-based diets.
    So, I would say that the biggest threat to production 
agriculture's future in the United States isn't so-called 
manmade climate change. The biggest threat to production 
agriculture's future in the United States is the Green New Deal 
and these extreme climate change agenda policies of the 
Majority party. And raising the cost of energy is something 
that should be addressed by this Committee. We should have a 
hearing on it because when you dramatically raise the cost of 
energy, you are going to undercut the profitability of farmers 
and you are going to take generational farmers and run them out 
of business, and we are going to disrupt this incredible system 
of agriculture that we have in our country.
    With that, I yield back.
    Ms. Adams. Thank you very much.
    I want to recognize the gentleman from California, Mr. 
Carbajal. You are recognized for 5 minutes.
    Mr. Carbajal. Thank you. Thank you very much, Madam Chair.
    I represent one of the most beautiful places on Earth, the 
Central Coast of California. It features some of the most 
diverse habitats in North America, and it is also home to a 
robust and diverse range of agriculture products--or 
production, I should say.
    Over the past decade, California has become more prone to 
weather extremes, and the Central Coast is no exception. Our 
community has felt the climate change crisis in a multitude of 
ways: more severe droughts, increasing frequency of heatwaves, 
and record setting wildfires.
    Producers in my district are utilizing funding from 
Environmental Quality Incentives Program, EQIP, and the 
Conservation Stewardship Program, CSP. While I am glad to see 
farm operations in my district using important conservation 
practices, I have also heard that access to these programs can 
be improved.
    Mr. Duvall, can you discuss the role of USDA conservation 
programs in addressing climate change, and helping farmers 
build resiliency? Can you speak to the demand for USDA's 
conservation programs?
    Mr. Duvall. Well, thank you, sir, for the question. I will 
tell you that those conservation programs are widely used, and 
I will tell you there are a lot more people that apply for them 
than actually receive them, because they run out of funds. 
There are not enough funds there to complete every project that 
a farmer will put forward. So, I think a lot of it is limited 
by the amount of funds that the Secretary has put in those 
areas. But they are widely used and they are widely popular.
    Mr. Carbajal. Thank you.
    Agriculture employers are constantly challenged by 
unpredictable weather, and they now have an ever-increasing 
need to protect farmworkers from extreme weather concerns.
    Ms. Knox and Mr. Cantore, can you talk to me about the 
effects climate change has on farmworkers? What health risks 
may they experience while working in extreme weather 
conditions, including poor air quality due to smoke?
    Ms. Knox. Well, let me start off by saying that there are 
several different ways that farmworkers are affected by it. One 
is by the likelihood of increased heat stress. Farmers working 
outside, especially as temperatures go up, are more prone to 
have heat-related diseases, and so people who hired them have 
to make sure that they are providing appropriate health-related 
cooling areas or whatever, or modifying hours to make sure that 
the heat stress is not building up on them.
    But as you point out, the air quality, especially in the 
western United States, is a very huge concern for people that 
are working outside. We have seen that with the vineyards and 
some of the vineyards that have really been hit by the fires 
out West, and how that smoke has really carried a long ways.
    But I will stop so I can let Mr. Cantore answer that as 
well.
    Mr. Cantore. I mean, when you take a look at the fire 
situation just last year, over 4 million acres burned. The 
pictures that we saw out of San Francisco looked like some kind 
of movie set, but that was real, and those people had to 
breathe that air for days, workers alike.
    So, if we get into a situation where these droughts worsen, 
and we get into these mega droughts that go year after year 
after year, and you increase 4 million acres two to six times, 
it is not only San Francisco and the vineyards that are going 
to be dealing with poor air quality. It could be the whole 
state. As a matter of fact, it is not just the whole state. A 
lot of that air, that poor air quality is carried east into 
other states, across the Rockies, to the Plains, into the 
Southeast. Heck, down here in Atlanta. You probably have seen 
the smoky skies, and it is not from the African dust but the 
smoke from the wildfires in the West. So, everybody suffers 
from this, and that is, to me, one of the worst things in terms 
of air quality.
    Mr. Carbajal. Thank you both for your answers.
    I happen to have agriculture as the number one industry in 
my district, and at the same time, I come from a family of 
farmworkers. So, I happen to see it from both perspectives, and 
I really do appreciate your answers.
    With that, I yield back, Madam Chair.
    Ms. Adams. Thank you. I want to recognize the gentleman 
from Texas, Mr. Cloud. You have 5 minutes, sir.
    Mr. Cloud. Thank you very much. I appreciate the 
opportunity to have this conversation. It is extremely 
important that we do have a discussion on how to steward our 
nation's resources.
    Mr. Brown, I have to say, not to invite myself over, but I 
do hope that one day I can visit what you are doing there. It 
seems like you are doing some great work. You mentioned that 
your regenerative farming practices are able to produce more 
per acre while also increasing profit and being more effective. 
Is that what I understood?
    Mr. Brown. That is correct, and we are doing it in Texas 
also.
    Mr. Cloud. Okay. Well, that is even closer, so maybe I will 
have to stop by.
    So, there is a built-in incentive already to move this way, 
am I correct?
    Mr. Brown. That is correct. I didn't get any incentives. I 
did it all on my own. I did, though, early on take advantage of 
EQIP and CSP contracts through NRCS. That was an important part 
of me starting down this path, but as soon as I was financially 
able to do it on my own, I would rather see that money go for 
other underserved or people who are starting out.
    Mr. Cloud. So, there is some initial cost getting started, 
and once you got started, it is self-sustaining, I guess is 
what you are saying, right?
    Mr. Brown. That is correct.
    Mr. Cloud. And you were able--I mean, this was just 
motivation in your heart to do, right? This was voluntary?
    Mr. Brown. Okay. No, my story was I started no-tilling 
actually in 1993. That I started on my own because it made good 
sense in my semi-brittle environment. Then what happened, the 
years 1995 through 1998, I lost 3 years of crops to hail, and 1 
more year to drought. Financially I was going broke, and I had 
to figure a way how can I make my soils, my resource productive 
without all the expensive inputs? And that sent me on an 
education and learning process, at times learning from land-
grant institutions, at times learning from other producers, 
learning from ARS. ARS was very important in my learning. And I 
picked up bits and pieces and learned these principles, and 
learned that they can truly work anywhere in the world where 
there is land-based agriculture.
    Mr. Cloud. Thank you very much.
    I would like to say that the road to $30 trillion of debt 
is paved with good intentions. Of course, we do have a role to 
play here in the Federal Government, and there are important 
investments we need to make.
    Mr. Duvall, I am not sure you are the best one to answer 
this. Do you have an estimate on how much it would cost to 
establish and operate a carbon bank?
    Mr. Duvall. No, sir, I am not qualified to answer that 
question.
    Mr. Cloud. Or anyone else? I don't know if anyone else 
does. No? Okay.
    I mean, currently we have some volunteer carbon banks in 
place, and right now, the highest cost, my understanding, in 
operating them is the cost of verification. Basically, a severe 
bureaucratic burden. Only ten percent of it goes to the farmer, 
and so, in pragmatic terms, I don't know of many programs where 
the government has done things more efficiently, so I do have 
some concerns in that. Because pragmatically, and this would be 
typical of many Federal Government programs, is basically we 
would be taking $10 of investment out of another industry that 
also needs to make gains, transferring it through the Federal 
Government to the ag industry. Eight dollars of that would be 
lost in the bureaucracy somewhere, and only $1 would go to the 
farmer. And while that would be some small benefit to the 
farmer, a lot of the overall cost of what we could accomplish 
basically would be lost in a Federal bureaucracy.
    So, it seems to me that we have to be very careful about 
overreaching here. I think, as has been stated, communication, 
education on the best practice is extremely important. And I 
would say not mandating the best practices, I wonder if Mr. 
Brown would have been able to make the advancements he made if 
we locked in the best practices of 20 years ago as a mandate, 
would allow that to happen as an environment that allows for 
innovation. And to that point, I would like to just say, Mr. 
Shellenberger, I really appreciated your balanced testimony and 
information-based evaluation of the state we are in as a 
nation. Too often we see the road left to the advancements that 
we still need to make, and sometimes those get demonized and we 
don't take the time to remember how much progress we have made. 
Could you just summarize and recap the United States, among 
other nations, the innovations we have made toward effective 
and sustainable farming?
    Mr. Shellenberger. Yes, I mean, gosh. There are so many of 
them, right? We are a huge innovator. I mean, all of the 
technologies in your iPhone, in those GPS-driven tractors----
    Ms. Adams. The gentleman's time is up. The gentleman's time 
is up. Thank you.
    I would like to recognize the gentleman from California. 
Mr. Harder, you are recognized for 5 minutes.
    Mr. Harder. Wonderful. Thank you so much. Thank you so much 
to Chairman Scott and Chair Adams, and thank you for hosting 
this hearing on this important topic. Thank you so much to the 
witnesses for contributing your testimonies.
    I think that in our valley, we have really seen--the 
California Central Valley, we see farmers on the forefront of 
climate change, especially in our district. We have seen 
farmers face wildfires, face droughts, face floods, and I know 
how much the changing climate can impact them. It is not just 
affecting some polar bear in the Arctic somewhere else. It is 
affecting the everyday lives of every farmer and grower 
throughout our community. And I think folks really want to be 
part of the solution. I took a lot of time with our Farm 
Bureau, discussing updating farm equipment, by using low dust 
harvesters on almond orchards. And frankly, there is a lot of 
interest. But folks on the ground often express some of the 
financial challenges in purchasing or updating their equipment 
or technology, or needing staffing assistance to keep growing 
their climate updates. One of my constituents shared that for 
her almond orchard, it would cost about $200,000 for a low-dust 
harvester, and an additional $70,000 for a low emission 
tractor. And so, with my work in business and startups, that 
was my background before coming to Congress, I understand how 
these decisions are made. And I understand that they really 
need to make financial sense if ag operators are going to move 
them forward.
    So, we have worked a lot with ag groups and environmental 
groups to introduce H.R. 7482, the Future of Agricultural 
Resiliency And Modernization Act, which I think is one of the 
only bills that is actually endorsed by our local Farm Bureaus, 
as well as by a number of environmental groups all around 
ensuring that we can make sure that we are moving towards more 
agricultural resilient practices. It basically creates a 
Federal partnership for farmers to access financing, which 
would provide grants that support climate-friendly projects. It 
also creates a pilot program for pyrolysis, which essentially 
helps convert tree nut byproducts into climate-friendly 
biocarbon, a really important effort especially in California's 
Central Valley.
    So, my question is actually for you, Mr. Duvall. As the 
President of the American Farm Bureau with such a wide-ranging 
network of members across our district, what have you heard are 
the financial needs of farmers in this space, and how can 
Congress or the Federal Government support farmers when making 
those financial decisions towards more climate resiliency? 
Thank you.
    Mr. Duvall. Well, thank you for the question, Congressman, 
and you are exactly right. Other than trying to figure out how 
some of these programs are going to work, and what regulations 
come along with it and the burden that comes with it, is the 
cost. You are exactly right. What is it going to cost me to put 
this practice on the ground? What new equipment am I going to 
have to buy? And then, you are exactly right. My membership 
goes from small, medium, large, different size organizations. A 
large organization might can afford that $200,000 piece of 
equipment, but a small operator can't and it makes it just not 
feasible for him to do that.
    If we have practices or we have policies put in effect, we 
have to make sure that there are monies that follow that 
practice or that policy, monies that are going to help farmers 
and assist them in order to put those practices on the ground.
    And whether it is all Federal Government or whether it is 
private or public together, and how all that fits together, 
someone else would have to figure that out. But you are exactly 
right. It is very expensive for some of those new projects to 
get put on the ground, and the new policies that are going to 
be put into effect. There needs to be money to follow it. If 
Americans and the rest of the world want agriculture to be the 
answer to this problem, then we got to have partners to be able 
to meet those obligations that we are going to have to meet to 
be successful and do it.
    Mr. Harder. Well said, Mr. Duvall. Thank you for that.
    We look forward to working with you. We have some strong 
partners with our local Farm Bureau, and I think there is a lot 
of interest. That is the good news. I mean, I think folks want 
to be able to adopt 21st century technology, 21st century 
practices. They just want to know how to pay for it, and I 
totally get that. I mean, it has to make business sense, and 
the question is, as legislators, how can we help them have it 
make business sense? And I think we are looking forward to 
working with you on some ideas for that.
    Thank you so much for your time, and I yield back the 
remainder, Ms. Adams. Thank you.
    Ms. Adams. Thank you.
    I want to recognize the gentleman from Kansas, Mr. Mann, 
you have 5 minutes.
    Mr. Mann. Thank you for the time.
    Thank you, Chairman Scott, for your remarks about ensuring 
that agriculture is in the pole position in these discussions, 
and that we highlight the climate solutions that are produced 
by agriculture while our producers feed, fuel, and clothe not 
only the country, but really the world.
    I proudly grew up on a farm in Quinter, Kansas, population 
800. I was the fifth generation to live in my house. My folks 
and my brother still run our farming operation. We raise corn, 
milo, wheat, had a feed yard, spent thousands of hours on a 
tractor combine, doctoring sick calves, really a privilege to 
get to grow up there. And I think it is important in these 
discussions that we all remember that agriculture also is the 
lifeblood to keeping a lot of our basic values alive that we 
hold dear in this country. Those values being faith, family, 
looking out for our neighbors, working hard. The values that 
are central to us as Americans are supported by agriculture, 
which makes these discussions all the more important.
    I proudly represent the big 1st District of Kansas, one of 
the biggest ag producing districts in the country. We are 
number one in the country on beef production. We are number one 
in the country on wheat production, number one on sorghum 
production, number three on corn production. We also have 
biofuels, food processors, dairies. It is a privilege and honor 
to get to represent these groups.
    My question also is for Mr. Duvall. So, I don't know if you 
remember this, Mr. Duvall. I was our Lieutenant Governor of 
Kansas, and you and I were in southwest Kansas in Garden City, 
and checked out some water technology farms and spent the day 
together. I really enjoyed that day. It would have been almost 
2\1/2\, 3 years ago.
    One of my big takeaways--and my question will be for you, 
Mr. Duvall, like I said, is--and I think one thing we got to 
continue to highlight is we all should be encouraged to hear 
about the strides that American farmers and ranchers have made 
in addressing and mitigating carbon, especially with the 
reduction of agriculture's share of greenhouse gas emissions 
from 24 percent in 2010 all the way down to ten percent here in 
2019. So, in 9 years we have gone from 24 percent down to ten 
percent. Remarkable. And I guess my question for you, Mr. 
Duvall, is can you explain how that reduction was made by 
farmers and ranchers in the U.S. in your mind, even as they 
continue to provide a safe, reliable, and affordable food 
supply? It is an amazing accomplishment and we need to keep 
highlighting it. I am just curious to know your perspective. 
Many of your members were part of that, and how do we go about 
accomplishing that?
    Mr. Duvall. Sure, and there is not one answer that answers 
that question, because we have talked about all of them here, 
the opportunity to participate in the programs through the USDA 
that are partnerships and incentive-based. Our farmers have 
latched on to that.
    Technology that has come from the research from--whether it 
be the plant and how we can not have to disturb the soil to get 
rid of weeds, but we can control them with other products, and 
we can do it with GPS and in precision plant farming. So, we 
have just come a long way in the techniques that we use, and we 
can do that because of the technology. We could go so much 
further if we go back and talk about streamlining the approval 
of these new technologies coming, increase the research. And we 
can even do more to not just lower our emissions, but to help 
take in--take care of some of the problems of the emissions 
from other areas of other industries.
    So, there is not one answer that answers that question. Our 
farmers are resilient, and they are technical savvy, and they 
will take advantage of every opportunity, and we have to have 
broadband to make sure that we can take care--utilize the new 
technology that is coming in the future, because precision 
agriculture is here, and our farmers aren't wearing overalls 
anymore. They are carrying computers and iPads around with them 
to get the job done, and broadband is important.
    And your part of the state and that travel--that visit was 
wonderful. I absolutely fell in love with that part of our 
country.
    Mr. Mann. Well, glad to have you, and you really touched on 
my next question, and that is, in my view, rural broadband has 
got to be a part of this discussion, because to really continue 
to improve on carbon, we have to have precision agriculture and 
rural broadband is the technological underpinning of that. So, 
I could not agree with you more, Mr. Duvall.
    Thank you for all of our panelists today. I really 
appreciate your time. And with that, I yield back.
    Ms. Adams. Thank you. I want to recognize now the 
gentlelady from the State of Washington, Ms. Schrier. You are 
recognized for 5 minutes.
    Ms. Schrier. Well, thank you, Madam Chair.
    Some of the biggest concerns that I hear from farmers in my 
district in Washington State have to do with concerns about 
declining snowpack year over year, and therefore, less reliable 
water resources for irrigation that will only worsen over time 
because of our changing climate. And that is why researchers 
out of Washington State University's Tree Fruit Research and 
Extension Center in Wenatchee, Washington are exploring ways to 
sustainably secure and more efficiently use water. And their 
goal is, of course, to help farmers and growers produce food, 
given scarce and unpredictable water resources. And they have 
actually discovered that grape growers can achieve better 
yields with less water. So, with the changing climate, we do 
need both resilience and adaptation.
    Now, I want to focus on regenerative farming, which has 
been discussed so thoroughly today, and mostly how the Federal 
Government can support farmers. So, as discussed, regenerative 
agriculture refers to a constellation of practices like crop 
rotation, cover crops, and no- and low-till farming that 
improves soil health, sequesters carbon, reduce the need for 
fertilizer and water inputs, improve yields, and also help 
mitigate and adapt to climate change.
    Now, these practices help farmers and are also key elements 
in addressing climate change. So, farmers are driving, as we 
have heard today, so much of the innovation and leading the 
efforts to expand these practices, and after up front 
investments, these are win/wins for farmers, as we heard from 
Mr. Brown.
    But there are big front-end expenses, like drill seeding 
machines, and the payoff often doesn't happen until about 6 
years later. And I am really excited by the Biden 
Administration's commitment to climate solutions, including 
these agricultural solutions. So, what I would like to ask is 
how the USDA programs can help scale up? For example, the 
USDA's EQIP Program provides financial and technical on the 
ground assistance for conservation and regenerative 
agriculture.
    And so, I guess my question first is to President Duvall. 
Could you say how else can the Federal Government help, and how 
could we ensure lasting help that could get farmers all the way 
through those 6 years?
    Mr. Duvall. Well, of course you are exactly right. It takes 
a tremendous investment to move in the direction. Even Mr. 
Brown admitted that he took advantage of some of those 
programs, and then earlier, I made the statement--and I know it 
is true--that there are farmers that want to participate, but 
there are not enough funds there to do it. And you are exactly 
right. That no-till machine, it costs a lot of money, and if 
you are not a medium- or large-sized farmer, you may not be 
able to afford that.
    Ms. Schrier. I even asked farmers if they could share. Like 
if you could have one for the entire town, and you can't do 
that. They all plant at the same time.
    Mr. Duvall. Well, soil and water conservation district here 
owns one, and you can rent it from them. There is sharing going 
on, and that is a program that is very well-used here in my 
community.
    There are ways to do this, we just have to explore how to 
do it. But there are more people wanting to be involved in it. 
They are interested in doing it. They just want to--they don't 
want anybody to force it on them. Because every farm is 
different, and I think Mr. Brown made the point that his 
techniques work anywhere in the world. I don't disagree with 
that, but there are a lot of differences in soils and regions 
and weather patterns and everything else. Some work good, some 
work better, and we just have to--we can't have one thing that 
fits all.
    Ms. Schrier. Absolutely. Thank you.
    I want to ask a little bit about carbon credits, but I 
don't know that I have time for that. Can I ask just maybe in 
30 seconds, maybe Mr. Brown, can you tell me a little bit about 
biochar and whether that is being implemented? Whether that is 
something that can even be scaled?
    Mr. Brown. Thank you. Biochar is certainly a tool that can 
be used in the right context. Again, it comes back to carbon. 
So, in your situation, obviously in Washington State, you have 
sources of that carbon available where biochar could be made. I 
would use that as a tool starting out. I would look at the 
Johnson-Su bioreactor of adding biology, and then also a hidden 
gem you have is the Bread Lab there in Washington State. The 
work that Dr. Steven Jones is doing is just unbelievable with 
granule grains.
    Ms. Schrier. Oh, fantastic. I have one more thing. I am 
running out of time, which is just that I agree with everybody 
today that we need to have farmers at the table, and that is 
why I have invited Robert Bonnie, USDA's Deputy Chief of Staff 
for Policy and Senior Advisor on Climate to my district in 
order to sit down at a roundtable with my farmers to talk about 
climate policy, the good, the bad, and the ugly, and our 
farmers need to be at the table.
    I would like to submit that letter for the record.
    [The letter referred to is located on p. 387.]
    Ms. Adams. So ordered.
    Ms. Schrier. Thank you. I yield back.
    Ms. Adams. Thank you.
    I want to recognize the gentlelady from Illinois, 
Representative Miller, you are recognized for 5 minutes. 
Representative Miller? Okay. All right, the gentlelady is not--
I don't see her. Okay.
    I want to recognize now the gentleman from Alabama, Mr. 
Moore. You are recognized for 5 minutes, sir.
    All right. The gentlelady from Florida, Mrs. Cammack, you 
are recognized for 5 minutes. The gentlelady--is Mrs. Cammack 
here, gentlelady from--okay.
    The gentlelady from Minnesota, Mrs. Fischbach, you are 
recognized for 5 minutes.
    The gentleman from New York, Mr. Jacobs, you are recognized 
for 5 minutes, sir.
    The gentleman from Iowa, Mr. Feenstra, you are recognized 
for 5 minutes. Mr. Feenstra?
    The gentleman from--is that Iowa? No, the gentleman from 
North Carolina, Mr. Rouzer. You are recognized for 5 minutes, 
sir.
    The gentleman from Ohio, Mr. Balderson. You are recognized 
for 5 minutes. Okay.
    Let me go to the gentleman from California, Mr. Panetta. 
Mr. Panetta, you are recognized. Go ahead, sir.
    Mr. Panetta. Thank you, Madam Chair. Am I good to go?
    Ms. Adams. You can go ahead, yes.
    Mr. Panetta. There you go. Thank you. I appreciate that. I 
am fortunate to have sat down in my seat.
    Thanks to all the witnesses for being here. I appreciate 
your preparation and your contribution. I know it has been a 
long hearing, and I appreciate your patience with this. So, I 
appreciate your preparation, and of course, your participation 
in a very, very important hearing. And obviously, thanks to the 
Chairman for holding it, as well as the Ranking Member, ``GT''.
    Look, I think if there is anybody concerned--at least in my 
experience with my producers on the Central Coast of 
California, if there is anybody concerned with fresh air, 
healthy soils, and clean water, it is our producers. And I 
think that has been made evident today with the similar 
sentiments that have been expressed, not only from our 
witnesses, but from the Members on both sides of the aisle.
    I believe in my conversations and my work with my ag 
producers, they value and understand the concept that maybe 
some of you have or have not heard about. It is called 
usufruct. And basically, it is the temporary right to use the 
land, usus, to produce fruit, fructus, usufruct. And what that 
means is that they--I believe our producers understand that 
they are here. They use the land, but they also have to 
preserve it for our future, because they know it is not theirs. 
It is a temporary right. And that is important, because I 
believe that when it comes to dealing with the climate crisis, 
I can tell you, our producers understand that and our 
producers, therefore, as we have heard throughout this hearing, 
need to be at the table.
    And I also want to give a shoutout and acknowledge our new 
USDA Secretary Vilsack for his vision to ensure that our 
farmers are at the table. And I believe it is our obligation to 
ensure that our producers, especially mine on the Central 
Coast, many, many specialty crops, are at the table. And as 
many of you have heard me say--and it is the first full--well, 
second hearing in which we are having at this Agriculture 
Committee, I can say people know that I come from the Salad 
Bowl of the World, and therefore, we have a number of specialty 
crops. And so, obviously those types of producers have been 
progressive when it comes to maintaining and preserving the 
earth that they use to produce their fruits and vegetables.
    And so, I want to just focus on Mr. Brown right now. 
Obviously, when it comes to specialty crops--I know you are 
from North Dakota. My wife is from North Dakota up in Rugby. 
There are not many specialty crops up there, but when it comes 
to specialty crops, what type of smart agricultural efforts are 
there when it comes to their concern for climate crisis?
    Mr. Brown. The same principles apply, whether we are doing 
specialty crops, lettuce, salads, vegetables, fruits. We are 
working extensively in California working with your growers--I 
am sure some of them are--and the technologies they are using 
are these technologies to use these principles in order to 
lower their input costs. And they can do that. There was a 
previous comment that it takes 6 years to recoup the costs. 
That is not true at all. We are seeing significant savings by 
year 2, certainly by year 3. So, the same principles apply.
    Mr. Panetta. Okay. Let me pivot to Ms. Knox. Would you 
agree?
    Ms. Knox. Yes, I think there are a lot of immediate 
benefits. I mean, it doesn't take a long time to see benefits 
to the soil. It doesn't see--a long time to see other benefits 
to specialty crops. Here in Georgia, we are seeing people try 
new crops. We are growing satsuma mandarin oranges, and we are 
growing olives. You don't really think of Georgia as being a 
place to grow olives, but we do have a chance to expand into 
new areas that could be new markets, and to take advantage of 
that.
    But growing them regeneratively is definitely going to help 
the producers in the long run, because it will reduce the 
number of inputs.
    Mr. Panetta. Thank you.
    And speaking of Georgia, let me say hello to my friend, 
President Duvall. Obviously--let me first acknowledge the fact 
that he understands that the number one issue of agriculture 
right now is labor, and how important that is. However, we do 
have to deal with this climate crisis as well.
    And so, President Duvall, tell me how the American Farm 
Bureau has reached out to our specialty crop producers to 
ensure that they are at the table as well when it comes to 
coming up with a solution, or the many solutions that we have 
to come up with for dealing with the climate crisis in the 
field of agriculture production?
    Mr. Duvall. Congressman, ever since I have been at the 
American Farm Bureau, I have encouraged inclusiveness. That 
means all kinds of agriculture, all genders, all races to come 
to the table, because you know, it is our job and our mission 
to be able to provide one united voice of the American farmer. 
How can we do that without all of them being there? So, we have 
been pretty successful and----
    Ms. Adams. The gentleman is out of time.
    Mr. Duvall. Look, we are not here just to represent big 
agriculture, but we need you to come to the table and give us 
your ideas, and that is what we are trying to do.
    Ms. Adams. Thank you.
    Mr. Panetta. I look forward to being at the table with you, 
President Duvall.
    Thank you, Madam Chair. I yield back.
    Ms. Adams. Thank you. Are there any Republicans that I 
can't see that need to be recognized? Okay, then we will move 
on to the gentlelady from Iowa, Mrs. Axne. You are recognized 
for 5 minutes.
    Mrs. Axne. Thank you, Madam Chair, and thank you to 
Chairman Scott just for holding this hearing that is so 
important. It is such a pressing issue, and I really appreciate 
our witnesses being here today to share your expertise. I very 
much appreciate the testimony given and the discussions around 
how much our environment has been affected by climate change, 
and how substantial that cost has been.
    Jim, you noted in your testimony the increasing number of 
climate events that result in costs exceeding $1 billion, and 
what a shocking number: 22 events last year. But unfortunately, 
as you mentioned, those events have become all too common for 
folks back in my home State of Iowa. We are the ones who had 
the derecho sweep across our state, and when Iowans don't know 
what a storm should be called, it is definitely something out 
of the ordinary. And of course, we saw millions of farmland 
acres destroyed, left hundreds of thousands of Iowans without 
power. And then just a year prior to that in southwest Iowa in 
my district, we saw devastating flooding along the Missouri 
River, which destroyed homes and farmland up and down the 
river. And honestly, we simply cannot afford to accept that 
these events are the norm, and we have to take action on this 
climate crisis to reduce our carbon emissions and build up 
resiliency so that our farmers can be successful.
    So, my first question is to you, Mr. Brown. Thank you so 
much for sharing with the Committee the successes that you and 
others have experienced as a result of sound soil health 
practices. I was reading your written testimony, and I was 
taken by the story of Mr. Adam Grady from North Carolina. Two 
weeks after waters receded from Hurricane Florence, Mr. Grady 
was already seeding his fields. Like Mr. Grady, farmers in Iowa 
are facing increasing challenges combating excess moisture each 
year as a result of more frequent wet springs.
    Mr. Brown, can you just take a moment to describe how the 
soil health practices can help farmers adapt to floods and the 
changing climate more broadly?
    Mr. Brown. Well, thank you. That is an excellent question. 
I am going to hold up this jar to signify this is actually 
soybean seed in a jar, but think of it as soil aggregates. So, 
soil aggregate is just like one of these seeds. It is a little 
pad of sand, silt, and clay bound together. Water: your 
infiltration rates of water depend on those soil aggregates. A 
soil aggregate will only last about 4 weeks, and then new ones 
need to be built. In order to build new ones, you have to have 
soil biology. You have to have mycorrhizal fungi.
    We were holding a soil health academy there in southeastern 
Iowa, and they were bragging about the very rich soils of 
eastern Iowa. Unfortunately, they had \1/2\" of rain and that 
water could not infiltrate.
    You mentioned the flooding problems we are seeing along the 
Missouri and Mississippi Rivers, here in North Dakota, the Red 
River. Year after year we combat that. What we need to do to 
alleviate that is build soil aggregates. We can help alleviate 
our flooding, alleviate those costs that occur year after year, 
as you said, to society if we focus on the resiliency of our 
soils. We are not doing that anymore. I travel extensively, all 
50 states, and I have taken soil test after soil test after 
soil test that shows that we no longer have the ability to 
infiltrate water.
    In 2009, we had a major rainfall event on my ranch. We had 
12.6" of rain in 6 hours. The next day, I could go out in my 
fields and drive across them with the tractor and not leave a 
rut. It is all about biology and building back resiliency 
through soil health.
    In Iowa, they can certainly do that with the wonderful 
resources you have there.
    Mrs. Axne. Well, I appreciate that, and it is inspiring to 
hear this, and thank you.
    As your work as a farmer and educator takes you around the 
country, as you mentioned, what do you think are some of the 
biggest reasons that you hear from farmers that prevent them 
from adopting these soil health practices, and what technical 
and financial resources do you think are needed for us to 
encourage to scale up adoption of these practices?
    Mr. Brown. That is a wonderful question, one I get asked 
daily.
    The number one reason is fear. For farmers and ranchers it 
is fear of the unknown. Again, it goes back to education. The 
second is the current farm program. The current farm program, I 
am sorry, but it is not conducive to adopting these practices. 
We make small steps through NRCS and that, but then the 
production model is wrong. We are on a path through Risk 
Management Agency where the crops seeded revenue insurance 
determines 95 percent of what farmers and ranchers plant. 
Because they have to obtain operating money, operating notes 
from the bank in order to stay in production that year, that 
bank is going to tell them you have to take part in this 
program, and then you have to plant those crops that will allow 
you the greatest return through risk management.
    Don't get me wrong; we need crop insurance----
    Ms. Adams. The gentleman is out of time.
    Mr. Brown.--we need risk management, but it has to be 
changed. Thank you.
    Ms. Adams. Now, I want to recognize the gentlelady from 
Florida, Mrs. Cammack. You are recognized for 5 minutes, ma'am.
    Mrs. Cammack. Thank you so much, and good afternoon. I 
would like to thank the witnesses for hanging in there on this 
long hearing today and appearing before the Committee. I would 
also like to start by asking everyone who has had a meal today 
to please thank a farmer.
    While we have this important discussion about the 
environment, climate, and U.S. agriculture, it is important to 
remember that the realities already facing our farmers are 
pretty grim. Growers in my home State of Florida and those 
throughout the country continue to face a number of challenges 
to remain competitive in the face of rising foreign imports. 
These imports are not grown under the same high environmental 
standards adhered to by U.S. producers including standards for 
air, water, solid and hazardous waste, and not to mention the 
labor standards. This conversation about what more farmers need 
to do in order to protect our environment becomes a bit 
trivial, in my opinion, when our farmers are forced to add to 
food waste because they can't compete with cheaper imports, as 
I just saw last week in south Florida when our producers had to 
disk up crops simply because they could not compete with cheap 
imports. The disparities when it comes to labor, regulatory, 
and environmental standards have left our producers at a 
tremendous and devastating disadvantage.
    So, I would like to start out with Mr. Duvall. Thank you 
for being here with us. For the record, if you can, and in one 
word, from what you have seen, which country produces on a 
large scale the highest quality agricultural products with the 
lowest environmental impact?
    Mr. Duvall. The United States of America.
    Mrs. Cammack. I love that answer. And as a follow-up to 
that, Mr. Duvall, and in the same format, in terms of 
inequitable competition, which country poses the largest threat 
to American agriculture?
    Mr. Duvall. In your area, Mexico.
    Mrs. Cammack. Thank you.
    Mr. Duvall. Over-dumping product into your state.
    Mrs. Cammack. Absolutely, thank you.
    Ms. Knox, you mentioned in your testimony that the 
environmental impact that the clearing of land has on the 
release of carbon dioxide into the atmosphere. I want to ask, 
do you agree that it is more environmentally conscious to 
support our local producers here in the United States, rather 
than foreign producers held to looser regulation?
    Ms. Knox. I think supporting local farmers is always an 
important thing to do. It minimizes the cost of transportation 
to help support the local economy, and so, I--and they really 
farm more responsibly in a lot of ways, because we are more 
strict about our regulations. And so, I really support local 
farmers because of that.
    Mrs. Cammack. Excellent. Thank you, Ms. Knox, and I have to 
say go Gators, just because--well, you know why.
    Now, Mr. Brown, as you know, many American farmers are 
ready and willing to participate in carbon sequestration and 
implement regenerative agriculture. I have seen a clear desire 
to embrace these practices in my home State of Florida; 
however, I have also seen farmers frustrated by the prohibitive 
costs associated with implementation. In my district alone, we 
have producers that are forced to spend anywhere up to the tune 
of $300,000 just to participate in a carbon sequestration 
program. In your opinion, how can we make carbon sequestration 
and other green infrastructure investments more affordable for 
America's producers?
    Mr. Brown. Well, they should not be participating in that 
program if it is costing that. It is about much more than 
carbon. Farmers and ranchers need to be paid for all ecosystem 
services. We are talking about carbon, but it is much more than 
that. It is clean air, clean water. It is taking nutrients out 
of the watersheds, holding them on the farm where they belong.
    The way to do that is using the USDA programs to 
incentivize best use practices, and to educate those farmers 
and ranchers.
    Mrs. Cammack. Thank you.
    Mr. Shellenberger, you have done a tremendous amount of 
research and work developing your book, Apocalypse Never. Since 
I have about 40 seconds left on the clock, I would like to give 
you my remaining 30 seconds to give an elevator pitch as to why 
people should read your book, and what the biggest takeaway is.
    Mr. Shellenberger. Thanks for asking.
    I mean, the argument of the book is that climate change is 
real, but it is not our biggest environmental problem. Our 
biggest environmental problems stem from the inefficient use of 
land, particularly in poor countries, and if I had more time, I 
would have described all the work that I think American farmers 
can do to extend the innovative, efficient, and productive 
kinds of agriculture that we have developed here to poor and 
developing countries, because that is really what matters in 
terms of protecting natural ecosystems and lifting everybody 
out of poverty, which are goals that I think we all share.
    Mrs. Cammack. Thank you so much, and Mr. Cantore, I am sure 
I will see you in Florida later this year.
    And with that, I yield back.
    Ms. Adams. Thank you.
    The gentleman from Florida, Mr. Lawson, you are recognized 
for 5 minutes, sir.
    Mr. Lawson. Thank you, Madam Chair, and I will try to go 
real quickly.
    My question is going to be for Mr. Duvall. My district in 
north Florida is home to so much of the state's timber industry 
and working forests. Hurricane Michael in 2018 really pummeled 
our area's agriculture, delivering $1.2 billion in damages to 
timber. So, I am interested in policy that could incentivize 
reforestation and timber production, which could especially 
help producers in catastrophic events such as hurricanes.
    Can you talk about the merit of intensifying sustainable 
practices on these lands, and their contribution to our overall 
goal of mitigating climate change?
    Mr. Duvall. Yes, the forests around our country contribute 
huge help to solving the problems of climate change, and we all 
know that trees are the biggest sequestrator of any forage that 
is out there, any plant that is out there. So, you are exactly 
right. To incentivize people to be more in agriculture in a 
forestry area, we have to make it profitable again. The only 
way to make a living on forestry is to have tens of thousands 
of acres and not all the farmers have that. Very few have that, 
and the management tools that they use, our state forestry 
units are kind of confined with the resources. There is not 
enough money there to help people go out and--technicians to go 
out and help them put those practices on the ground, whether it 
be state or Federal. But I think that would be a huge help if 
USDA could help assist that.
    You come to your part of the country, my part of the 
country, we don't have forest fires because we manage our 
timber. We burn off that fuel. We make sure that that fuel is 
not there to harm all the homes that are around it. The 
management in forestry is vitally important, not just to being 
productive and not burning, but it is also important to 
sequestering carbon.
    Mr. Lawson. Okay, thank you very much.
    Ms. Knox, from tomatoes, citrus, specialty crops are 
critical in the Florida economy. Our land-grant institutions 
are doing great research to address these to our crops. I am 
concerned that climate change will only make the battle more 
difficult. Can you please go into a bit more detail regarding 
potential impact that climate change would have on, especially, 
specialty crops?
    Ms. Knox. I think climate change will affect them in a 
variety of ways. I think as temperatures go up, there may be 
some specialty crops that are not going to grow well in 
Florida, and they will look for new varieties that may be able 
to keep better. I think they are going to also worry a little 
bit about water availability, although as I understand it now, 
a lot of the specialty crops in Florida are already under 
irrigation, so there would be a question of will there still be 
water available? But I think that is probably not as important.
    I think one of the other issues is as the growing season 
increases--of course, part of Florida has a year-round growing 
season, but other parts still do see frost. We are going to see 
increases in the number of pests, and those pests aren't only 
coming locally, but they are also being blown in from other 
places, and we don't really know yet what the weather patterns 
are going to do as far as the wind shifting over time. And so, 
that is certainly something that could also be more than it 
shows. We get more of these pests and diseases that are blowing 
in and certainly affecting some of the specialty crops.
    Mr. Lawson. Thank you, Ms. Knox. That was really great to 
know.
    And with that, Madam Chair, I yield back.
    Ms. Adams. Thank you.
    The Committee will recess subject to the call of the Chair.
    [Recess.]
    The Chairman [presiding.] Thank you. Our Committee will 
come back to order. We are getting around to the finishing 
line. I can't thank everybody enough for hanging in there with 
us. It lets you know how serious everybody is about this very 
serious issue we are facing on climate change. Thank you for 
tolerating our interruptions, particularly our panelists who 
have been with us here since 12. Great. I really, really 
appreciate you.
    Now, we are going to finish up with our hearing. We have, I 
believe, Mrs. Fischbach from Minnesota. You are now recognized 
for 5 minutes.
    Mrs. Fischbach. Yes, sir.
    Thank you so much, and I hope everyone can hear me.
    First of all, thank you, Mr. Chairman, and I would 
especially like to thank all of the panelists for hanging in 
there with us. It has been an interesting day of running back 
and forth and all kinds of other things happening here, but 
thank you so much for hanging out with us.
    Mr. Chairman, there is no doubt that our changing weather 
patters presents challenges for farmers and ag producers, but 
while addressing those challenges, we must do so in a way that 
respects the industry and recognizes their achievements 
protecting our environment. Adding more regulations or pushing 
lopsided partisan measures is not the answer. Instead, we 
should incentivize farmers to adopt what many of them already 
do through innovation and ingenuity. The soils they cultivate 
better protect against erosion and nutrients lost. The 
equipment they use is far more efficient than just a few years 
ago, and farmers are utilizing technology to minimize inputs 
and further reducing their footprint.
    There is a challenge that must be met without partisan 
agenda. All of us agree that we each have a role in protecting 
our environment and farmers are some of the best stewards of 
our lands and resources. The farmers and producers I know want 
to be partners in this work, but nothing meaningful will happen 
by enacting punitive measures that malign their hard work, and 
it will happen by affording them the respect they deserve.
    That being said, Mr. Duvall, I firmly believe that any 
climate proposal that doesn't include biofuels in part of its 
calculus is not a serious proposal. This homegrown American 
energy source is a vital part of my district's economy, and 
many others of this Committee. Can you speak a little bit to 
the benefits of this product in reducing our emissions, and 
where it does fit in the climate-related proposals?
    Mr. Duvall. You are talking about renewable energies?
    Mrs. Fischbach. Yes, biofuels in particular, I am sorry.
    Mr. Duvall. Yes, ma'am. I mentioned earlier to another 
question that we need to make sure that we recognize that this 
country went and asked agriculture to be a part of our energy 
independence solution, and we are a piece of that pie. And the 
infrastructure around that is so important. About 30 percent--I 
stand corrected if I am wrong--but I think about 30 percent of 
the corn and 30 percent of the soybeans goes to biofuels, and 
now we are generating enough that we can even export it. It has 
been a tremendous lift to your part of the world and the 
Midwest, and it has not only helped the farmers, it has helped 
rural communities and kept them vibrant. And anything we do to 
hurt that industry is going to be devastating to that part of 
our country. So, we would not support anything that would hurt 
that infrastructure and the biofuel.
    Mrs. Fischbach. And Mr. Duvall, I appreciate that.
    Mr. Shellenberger, we just touched a little bit on some of 
the issues of broadband, and I am just wondering if you can 
comment on how that increased broadband connectivity plays a 
role in the discussion, and how it relates to the precision 
agriculture technology?
    Mr. Shellenberger. Yes, great question. I totally agree 
that it is essential what we have been seeing with the 
revolution in precision agriculture is the application of GPS 
and high-processing computers to be able to take efficiencies 
and productivity to the next level. So, yes, I think it is 
obviously in the public interest to support that expansion and 
it seems like a no-brainer from my point of view.
    Mrs. Fischbach. Well, and I will just comment on our last 
Committee hearing, I was dialing in remote from home and I had 
some connectivity issues, so it made quite the point that day.
    But I will yield back the remainder of my time. Thank you, 
Mr. Chairman.
    The Chairman. Now, Mr. Randy Feenstra from Iowa, 5 minutes.
    Mr. Feenstra. Thank you, Mr. Chairman, Chairman Scott and 
Ranking Member Thompson.
    First, I want to thank each of the witnesses for their 
testimony today. It is very important that we discuss how 
farmers, ranchers, and the agricultural industry have already 
been leading the world in reducing the environmental footprint 
and additional opportunities that exist for their continued 
leadership.
    I would like to quickly note that in Mr. Cantore's 
testimony, he made mention of the devastating derecho storm 
that impacted Iowa last year. While I believe this Committee 
must work to understand how we can help the agriculture 
industry to mitigate and be resilient against disasters, we 
must also ensure that we provide timely relief for producers 
devastated by damage. And this is something that I have been 
actively working on.
    With that, this question would be for Mr. Shellenberger. 
So, getting back to climate change, Iowa's agriculture 
community has been a leader in addressing climate change. I 
believe that biofuel production, just like Ms. Fischbach noted, 
and Iowa in the 4th District should be a leading--be made a 
leading role in the efforts to reduce carbon emissions. It is 
also important to recognize the potential of biofuels to 
further reduce the carbon intensity with the potential to be 
net carbon negative. Let me say that again. Biofuels can make 
things net carbon negative, unlike electric vehicles, 
especially if the Federal Government helps companies to 
implement innovative technologies.
    Green Plains Incorporated just announced last week that 
three of their bio-refineries, including the plant in Superior, 
Iowa, have entered into a carbon capture and sequestration 
project. In short, the project will transport CO2 
from Iowa to North Dakota for the deposit in their geological 
storage. This will allow these bio-refineries to reduce their 
carbon intensity by as much as 50 percent, comparable or lower 
than the other low carbon fuels available on the market today. 
Green Plains Incorporated cited that section 45Q tax credits as 
being important to allow the company to invest in these 
innovative technologies.
    So, Mr. Shellenberger, I think this aligns with your 
testimony's theme of encouraging technological innovations as 
an answer to climate change, instead of burdensome regulations. 
Could you discuss other incentives like the section 45Q credit 
that you believe would be helpful to drive innovation in the 
agriculture industry to reduce carbon emissions?
    Mr. Shellenberger. Sure. Yes, I mean, I think all of those 
investments are important, both for carbon sequestration and 
for biofuels. I think in the past, we have over-subsidized the 
production of biofuels when I think more targeted R&D was 
merited, so I haven't looked at the specific projects you 
mentioned, but clearly, this kind of cooperation to solve 
specific problems I think is the way to go. There are some 
calls that have been made for kind of generic increases of 
innovation that I don't think make as much sense. But I think 
we have seen, obviously, with the coronavirus vaccine and the 
Shale gas revolution, nuclear power, genetically modified seed 
technologies that when we have a specific objective that we are 
trying to achieve, that the public- and private-sector can come 
up with some really remarkable innovations. So, I think that 
those are all great directions to be going in.
    Mr. Feenstra. Thank you, Mr. Shellenberger.
    So, if you could--just a little more--would it be more 
beneficial--I mean, you think of biofuels and if you could make 
something net carbon negative, wouldn't that be the paramount 
structure of what we all desire?
    Mr. Shellenberger. It would. I think the challenge with 
biofuels, as you know, we have had a challenge in terms of 
counting the carbon sequestration and emissions in the past. 
There has been a pretty significant debate about whether 
clearing land for biofuels actually results in a net loss or a 
net gain of carbon emissions. So, I just think it is an area 
that we need to proceed with some amount of caution, because I 
do think we have seen biofuels scaled up in the past that have 
not really panned out in terms of their benefit. So, I think we 
need to take a close look at which of the biofuels we are 
using, and how we are doing those calculations.
    Mr. Feenstra. Sure. Thank you.
    But wouldn't that be the same for electric vehicles? I 
think that exactly what you just said would be noted for 
electric vehicles also. Would that be a fair statement?
    Mr. Shellenberger. Absolutely, and there is a very active 
debate within the energy analysis community about whether 
electric vehicles are going to be the right solution, or 
whether it would be hydrogen-powered fuel cell vehicles. There 
are good arguments on both sides. I am personally agnostic 
about it. I think they have to be decided on a case-by-case 
basis. There are reasons to think that hydrogen is the way we 
will be going in the long-term, but again, I just think it is a 
little bit too early to say.
    Mr. Feenstra. Well, thank you for your comments, Dr. 
Shellenberger. I greatly appreciate them. I am still a believer 
that the combustion engine can do great things, as long as we 
can provide a negative carbon footprint.
    Anyway, thank you. I yield back my time.
    The Chairman. Well, thank you so much, and let me just say 
how grateful and just how thankful we all are on this Committee 
for the outpouring of help and knowledge and information, 
accurate, that will help us that you five experts have given to 
us today. We thank you for the time that you have put in. This 
has been a long and thorough hearing.
    But let me just tell you the great good that you all have 
done too this day, because as I said in the outset, our whole 
thrust forward to deal with climate change must be anchored in 
agriculture. That is the major and critical thing we have 
established today. And that is what is important.
    So, to you, Mr. Jim Cantore--and I think I got your name 
right--the senior meteorologist--and I hope I got that one 
pronounced--of The Weather Channel, thank you. Thank you so 
very much.
    Ms. Pamela Knox, Director of the University of Georgia's 
Weather Network, thank you for your piercing insights that you 
gave to our Committee.
    And to Zippy Duvall, my good friend and fellow Georgian, 
President of the American Farm Bureau Federation, thank you. 
You brought such great insight directly from the perspective of 
our farmers. They are the ones that we want to make sure our 
climate change is based upon making sure our farmers are not 
only at a seat at this table for climate change, but at the 
head of the table. Our farmers.
    Mr. Gabe Brown of Brown's Ranch, the Brown's family ranch 
from Bismarck, North Dakota, thank you so much. You brought 
such great wisdom and information of which many of us were only 
dimly aware on this Committee. Thank you for that.
    And also, I mentioned Mr. Gabe Brown from Bismarck, North 
Dakota. And Mr. Michael Shellenberger, President of 
Environmental Progress. The five of you have done a wondrous 
benefit, not only for this Committee, but for the nation. We 
have received information that literally thousands of people 
across this country were tuned in to this hearing, and that is 
what is important.
    So, from the bottom of my heart and the bottom of the heart 
of our Agriculture Committee here, we just want to say thank 
you, and God bless you.
    Now, I turn it over to you, Ranking Member, for your 
closing remarks.
    Mr. Thompson. Well, thank you, Mr. Chairman. Thank you to 
our witnesses. They did just a tremendous job. And I have to 
say, an impressive turnout by our Members on both sides of the 
aisle participating in this. I know we went long, but that is 
because it shows the passion and the interest of the Members. 
Thank you, Mr. Chairman. I thought it was an efficiently run 
hearing. You got that much interest, and I think we are going 
to have long hearings because of the commitment of the Members 
that we have on the Agriculture Committee.
    United States agriculture is the most productive and the 
most successful at mitigating greenhouse gases than anywhere 
else in the world. Our goal must be a healthy environment and a 
healthy economy. You cannot compromise one over the other. 
Anything that we do needs to be both good for the environment 
and for the economy. And that, quite frankly, means the 
economics of our farm and ranch families, money in their 
savings accounts and their checking accounts as well. 
Agriculture has the solutions. U.S. agriculture has the 
science, and U.S. agriculture has the proven outcomes when it 
comes to this topic of climate. Our focus should be climate 
solutions that are based on science, innovation, technology, 
and voluntary led conservation. That defines American 
agriculture.
    So, thank you, Mr. Chairman, and I yield back.
    The Chairman. Well, thank you, and before I adjourn, of 
course, none of this would have happened had it not been for 
our great staff, Ranking Member, and I am speaking on your side 
and mine. They worked night and day to pull this hearing 
together, and I tell you, I want to say just a big thank you to 
our great staff here in the Agriculture Committee for the great 
work that they have done.
    Mr. Thompson. I certainly agree. They make us look pretty 
good.
    The Chairman. I think so.
    So, with that, then this hearing comes to an end, and thank 
you all very much for your participation.
    Thank you.
    [Whereupon, at 5:31 p.m., the Committee was adjourned.]
    [Material submitted for inclusion in the record follows:]
 Submitted Articles by Hon. David Scott, a Representative in Congress 
                              from Georgia
                               Article 1


[https://ehp.niehs.nih.gov/doi/10.1289/EHP41]
Environmental Health Perspectives
Estimated Effects of Future Atmospheric CO2 Concentrations 
        on Protein Intake and the Risk of Protein Deficiency by Country 
        and Region
[Is companion of Estimated Deficiencies Resulting from Reduced Protein 
Content of Staple Foods: Taking the Cream out of the Crop? (https://
ehp.niehs.nih.gov/doi/10.1289/EHP2472)]
Danielle E. Medek,1, 2 Joel Schwartz,\1\ and Samuel S. Myers 
1, 3
---------------------------------------------------------------------------
    \1\ Department of Environmental Health, Harvard T.H. Chan School of 
Public Health, Boston, Massachusetts, USA.
    \2\ Waitemata District Health Board, Takapuna, Auckland, New 
Zealand.
    \3\ Harvard University Center for the Environment, Cambridge, 
Massachusetts, USA.
    Address correspondence to D. Medek, North Shore Hospital, 
Shakespeare Ave., Takapuna, Auckland, New Zealand 0622. Telephone: 
6494868900. Email: [email protected].
    Supplemental Material is available online (https://doi.org/10.1289/
EHP41).
    The authors declare they have no actual or potential competing 
financial interests.
    Received 27 February 2016; Revised 12 September 2016; Accepted 19 
September 2016; Published 2 August 2017.
    Note to readers with disabilities: EHP strives to ensure that all 
journal content is accessible to all readers. However, some figures and 
Supplemental Material published in EHP articles may not conform to 508 
standards due to the complexity of the information being presented. If 
you need assistance accessing journal content, please contact 
[email protected]. Our staff will work with you to assess and 
meet your accessibility needs within 3 working days.
---------------------------------------------------------------------------
Abstract
    Background: Crops grown under elevated atmospheric CO2 
concentrations (eCO2) contain less protein. Crops 
particularly affected include rice and wheat, which are primary sources 
of dietary protein for many countries.
    Objectives: We aimed to estimate global and country-specific risks 
of protein deficiency attributable to anthropogenic CO2 
emissions by 2050.
    Methods: To model per capita protein intake in countries around the 
world under eCO2, we first established the effect size of 
eCO2 on the protein concentration of edible portions of 
crops by performing a meta-analysis of published literature. We then 
estimated per-country protein intake under current and anticipated 
future eCO2 using global food balance sheets (FBS).
    We modeled protein intake distributions within countries using Gini 
coefficients, and we estimated those at risk of deficiency from 
estimated average protein requirements (EAR) weighted by population age 
structure.
    Results: Under eCO2, rice, wheat, barley, and potato 
protein contents decreased by 7.6%, 7.8%, 14.1%, and 6.4%, 
respectively. Consequently, 18 countries may lose >5% of their dietary 
protein, including India (5.3%). By 2050, assuming today's diets and 
levels of income inequality, an additional 1.6% or 148.4 million of the 
world's population may be placed at risk of protein deficiency because 
of eCO2. In India, an additional 53 million people may 
become at risk.
    Conclusions: Anthropogenic CO2 emissions threaten the 
adequacy of protein intake worldwide. Elevated atmospheric 
CO2 may widen the disparity in protein intake within 
countries, with plant-based diets being the most vulnerable. https://
doi.org/10.1289/EHP41.
Introduction
    Globally, 76% of the population derives most of their daily protein 
from plants (FAO 2014a). With projected population growth to 9.5 
billion by 2050 (UN 2013), alongside dietary and demographic changes, 
future nutritional demands may overwhelm global crop production 
(Alexandratos 1999). Compounding the strain on food supply, plant 
nutrient content changes under elevated atmospheric carbon dioxide 
concentrations (eCO2) (Myers, et al., 2014).
    Under the CO2 concentrations predicted in the next 50 y, 
crops with C3 photosynthesis, such as rice and wheat, may 
experience up to 15% decreases in grain protein content (Myers, et al., 
2014). The effects of eCO2 are less on C4 crops, 
such as maize and sorghum, and on nitrogen-fixing plants, such as 
legumes (Myers, et al., 2014). Thus, the impacts of eCO2 on 
dietary protein intake will depend on which staples a country consumes, 
their dependence on the staple for protein, and their current risk of 
protein deficiency.
    Protein deficiency usually co-occurs with energy and micronutrient 
deficiencies (Millward and Jackson 2004). Insufficient protein intake 
limits growth, tissue repair, and turnover (Gropper and Smith 2008). 
Few controlled studies investigate protein deficiency syndromes in 
otherwise energy and nutrient sufficient diets. In renal disease, 
isocaloric protein reduction decreased lean body mass and lymphocyte 
count (Ihle, et al., 1989; Klahr, et al., 1994). In elderly women, 
these diets reduced cell mass and protein synthesis while impairing 
muscle function and immune status (Castaneda, et al., 1995). Low 
protein intake contributes to wasting, stunting, intrauterine growth 
restriction, and low birth weight (Black, et al., 2008). Together with 
protein-energy malnutrition syndromes, this causes an estimated 90.9 
million disability-adjusted life years (DALYs) and two million deaths 
annually (Black, et al., 2008).
    Previous meta-analyses conducted on the effects of eCO2 
on plant nutrient contents (Taub, et al., 2008; Loladze 2014) have not 
assessed eCO2 impacts on edible protein from a global 
dietary context, nor did they consider distributional effects within 
countries. We aimed to estimate eCO2 impacts on global 
protein intake, and on the proportion of the population by country at 
risk of protein deficiency. We aimed to expand on the meta-analysis by 
Myers, et al. (2014), including all available studies reporting 
eCO2 impacts on the edible portions of crop plants, 
including lesser-studied foods and studies in (sub)tropical locations. 
Then, using published food balance sheets (FBS) and measures of 
economic inequality within countries, we aimed to estimate dietary 
protein intake under current and future atmospheric CO2. We 
thereby tested the sensitivity of global protein intake and inequality 
of intake to rising atmospheric CO2, identifying key regions 
to target with nutritional interventions.
Methods
Systematic Review and Raw Data
    We conducted ISI Web of Knowledge (https://pcs.webofknowledge.com/) 
literature searches in July-September 2014 and in January 2016 for the 
effects of eCO2 on the protein content of all plants listed 
in the FAO FBS. This study supplements the meta-analysis of common 
European/U.S. staples conducted by Myers, et al. (2014). Because 
estimates of plant protein are commonly derived by multiplying measured 
plant nitrogen (N) by a conversion factor, we considered published 
changes in N and protein to be equivalent (Taub, et al., 2008). For the 
full search string and exclusions, see ``Part 1'' and ``Part 2'' in the 
Supplemental Material. A total of 119 citations were used. For 
references, see ``Part 3'' in the Supplemental Material.
    We included raw data from free-air CO2 enrichment (FACE) 
and open-top chamber studies, with data from European wheat, barley, 
and potato Changing Climate and Potential Impacts on Potato Yield and 
Quality (CHIP) and the European Stress Physiology and Climate 
Experiment (ESPACE) studies (A. Fangmeier, unpublished data, 1994-1999) 
and Australian wheat and pea Australian Grains Free Air CO2 
Enrichment (AGFACE), Japanese rice, American soy, corn, and sorghum 
Soybean Free Air Concentration Enrichment (SoyFACE) and Arizona FACE 
(data from Myers, et al., 2014). Raw data included free-to-air carbon 
dioxide elevation (FACE) and open-top chamber studies, 41 cultivars, 
nitrogen fertilizer, watering, and time of sowing treatments over 
multiple years.
    Response ratios (RRs) and standard errors (SEs) for protein 
response to CO2 were calculated from each study's reported 
error terms. When studies indicated merely significant at p<0.05 or not 
significant, the SE was calculated from p-values of 0.049 and 0.1, 
respectively.
Metaregression
    Metaregression was performed individually for each commodity where 
data were available from four or more experiments and for commodity 
groups listed in the FAO FBS (Table 1). We used the statistical package 
Metafor (version 1.9-4 Wolfgang Viechtbauer) in R (version 3.0.3; R 
Development Core Team). For each commodity or group, the difference 
between ambient (aCO2) and eCO2 treatments was 
tested as a modifier. We used multivariate linear (mixed-effects) 
models (the function rma.mv) with outcomes being percent decrease in 
protein, and modifiers being the difference between aCO2 and 
eCO2 in parts per million. Models included variance and were 
weighted by replicate facilities (e.g., number of FACE rings or growth 
cabinets) with random effects being year within site, and each cultivar 
(and unless tested as a modifier, each watering and nitrogen fertilizer 
treatment) was treated as a separate experiment. We performed Q tests 
to assess heterogeneity.

     Table 1. Percent change in protein content by commodity class.
------------------------------------------------------------------------
            Commodity (n)                  Estimate [mean (95% CI)]
------------------------------------------------------------------------
        C3 grains (257)                  ^8.14 (^12.17, ^4.1)
  Wheat (166).......................    ^7.78 (^13.24, ^2.32)
  Rice (66).........................    ^7.61 (^11.53, ^3.69)
  Barley (21).......................    ^14.05 (^20.7, ^7.39)
         C4 grains (12)                     2.07 (^3.2, 7.35)
  Maize (8).........................      3.08 (^5.19, 11.35)
  Sorghum (4).......................       0.26 (^6.31, 6.84)
    Root vegetable (15)                   ^3.42 (^8.61, 1.78)
  Potato (9)........................    ^6.38 (^10.33, ^2.42)
   Pulses, legumes (26)                   ^3.51 (^8.05, 1.04)
  Peas (15).........................      ^1.69 (^3.56, 0.18)
  Beans (7).........................      ^4.58 (^12.37, 3.2)
  Chickpea (4)......................   ^13.47 (^21.36, ^5.58)
         Oil crops (54)                   ^0.78 (^5.03, 3.47)
  Soy (44)..........................      ^0.49 (^2.92, 1.95)
  Rapeseed/mustard seed (5).........       0.92 (^8.9, 10.74)
     C3 Vegetables (32)                 ^17.29 (^30.78, ^3.8)
              Fruit (5)                  ^22.9 (^54.04, 8.24)
------------------------------------------------------------------------
Note: C3, crops with C3 photosynthesis; C4, crops with C4
  photosynthesis; CI, confidence interval; n, number of experiments,
  where each treatment/cultivar/experiment was treated as a separate
  experiment, yet experiments at the same location for the same crop
  were grouped together.

Meta-Analysis
    Because there was no reliable dose-dependent decrease in protein 
content with degree of CO2 elevation, we used meta-analysis 
to derive average response ratios comparing plants grown in 
aCO2 with plants grown in eCO2, where 
eCO2 was in the range of 500-700 ppm. We used the rma.mv 
function as for metaregression, but without the modifier term. Both 
meta-analysis and metaregression tested fixed effects of pot- versus 
field-grown plants and a qualitative measure of nitrogen fertilizer 
treatment, categorized as low, adequate, or high, based on descriptions 
in each study's experimental design. Neither modifier changed the 
magnitude of the CO2 response, and neither was used in 
subsequent analyses.
    We minimized publication bias by including unpublished data. 
Furthermore, we tested sensitivity to publication bias. For each 
commodity, we incrementally added experiments with no effect of 
eCO2 on protein content (RR 1, variance 0.5) until 
confidence intervals for RR crossed 1. Some commodities, including 
rice, were sensitive to null results, but wheat was insensitive to null 
results (see Table S3).
Food Balance Sheets
    The FAO FBS estimate per capita availability of each food-based 
commodity (including energy and protein contents). We averaged data 
over 2009-2013 FAO FBS. We assumed that protein availability equals 
protein intake, corrected for digestibility (FAO 2014a). Per 
convention, we assumed that plant-based protein was 80% digestible and 
that animal-based protein was 95% digestible (Millward and Jackson 
2004).
    The ``Vegetables, other'' and ``Cereals, other'' categories were 
large contributors to protein intake in some countries, and contained 
both C3 and C4 plants, and for vegetables, 
nitrogen fixers. We produced weighted estimates of the contributions of 
each these categories, using re-calculated 2009 FBS from the FAOstat 
classic platform (described fully by Smith, et al., 2015). We converted 
from total grams to grams protein, using food composition tables 
(Abdel-Aal, et al., 1997; USDA 2011; FAO 2012; Ballogou, et al., 2013; 
New Zealand Ministry of Health 2014). We assumed that the ``Cereals, 
other, not elsewhere specified'' category within the ``Cereals, other'' 
category was derived from C4 grains in sub-Saharan Africa, 
but from C3 grains elsewhere.
    To estimate the effect of eCO2 on protein intake in each 
country, we assumed constant mass-based consumption of each commodity 
over time, with declining protein content predicted by our meta-
analyses. We used commodity-based averages when available, and 
otherwise applied the averages from the commodity group to each 
commodity (Table 1). We found no studies on eCO2 response of 
tree nuts, thus conservatively assumed no change in their protein 
content. Likewise, we assumed no eCO2 effect on animal 
protein.
Plant-Based Diets
    Within a population, the lowest protein consumers also frequently 
consume the least meat (see World Food Programme household surveys; 
e.g., Santacroce 2008). For an extreme scenario, we reran the models, 
removing all animal-sourced foods (including eggs and dairy) from the 
diet, assuming no other changes in dietary fractional composition.
Intake Distribution
    We assumed a lognormal distribution of protein intake within 
countries (FAO 2014b), a cumulative distribution function, with the 
mean,
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

and the standard deviation,
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

where x is the national mean protein intake, as estimated above, and CV 
is its coefficient of variation. Because protein intake is likely to be 
related to household income, we estimated the CV of protein intake 
(CVprotein) from the Gini coefficient of national household 
income inequality. The national Gini coefficient for household income 
describes a Lorenz curve plotting the cumulative percentages of total 
income against the cumulative number of households from poorest to 
richest. Using linear regression, we compared per-household 
CVprotein from household surveys across 36 countries (FAO 
2014a) with contemporaneous national Gini coefficients (Arneberg and 
Pedersen 2001; Garcia, et al., 2001; Kim and Kim 2007; OECD 2009; 
Liberati 2013; USAID 2012; CIA 2014; Solt 2014; World Bank 2014). The 
FAO uses Gini coefficients, gross domestic product (GDP), and food 
prices to estimate CV for caloric intake (FAO 2015). We then estimated 
the national CVprotein from the country's Gini coefficient 
in the year closest to 2011. Owing to high uncertainty among future 
economic projections, we assumed each country's future 
CVprotein would remain constant.
Estimated Average Requirements
    We calculated a weighted estimated average requirement (EAR) (grams 
per day) for absorbed protein from the published EAR for adults (0.66g/
kg/d) and for children by age and sex, using current and mid-range 2050 
demographic projections (IOM 2005; UN 2013). For adults, the minimum 
safe protein intake in grams per day is based on the minimum healthy 
body weight calculated from the lowest 5th percentile of body mass 
index (BMI), this being 18.5 kg/m\2\ (WHO 1995). We calculated average 
height from national surveys (OECD 2009; Hatton and Bray 2010; USAID 
2012). Where male height was unavailable, it was calculated as 1.08 
female  height, based on the median male-to-female height ratio across 
all countries. For child weight, the ideal body mass was the 50th 
percentile by age from growth tables (WHO 2006). We adjusted EAR to 
include the increased protein requirements of pregnant and lactating 
women (IOM 2005) with demographics estimated from projected birth 
rates, 2009 stillbirth rates and infant mortality, and breastfeeding 
prevalence and duration (McDowell, et al., 2008; AIHW 2011; CDC 2011; 
UN 2013; USAID 2012; Liu, et al., 2013).
Risk of Protein Deficiency
    From each country's 2050 population, we calculated the proportion 
and the number of people whose intake fell below the EAR under current 
and eCO2 scenarios, with the difference between these 
populations being our measure of impact.
    We used Monte Carlo methods to propagate error from the SE of the 
meta-analysis results, and for modeled CVprotein, through 
the model, using 10,000 random draws from normal distributions of mean 
national protein intakes, and again for error around linear regression 
of CVprotein on Gini coefficient. From these two parameters, we 
calculated the means (m) and standard deviations (s) of 10,000 
lognormal distributions. These were used to estimate the probability 
for each country of protein intake being below the calculated EAR.
    We summarize data based on regional classifications from the 
reporting regions of the Global Burden of Disease Study 2010 (Lim, et 
al., 2012), but we present India and the greater China region 
separately because of their large population sizes.
    At each stage of analysis, where country-specific data were 
unavailable, data were derived from regional estimates, which were in 
turn derived from weighted means by population size of each available 
country represented within the region (see Table S4 for regions).
Protein-Energy Ratio
    Assuming all calories lost from declines in food protein contents 
were replaced as carbohydrates (as supported by the stoichiometry of 
Loladze 2014), we calculated the ratio of protein to total energy in 
current diets and projected diets under eCO2. Because 
commodity-based digestibility of energy is less easily estimated, 
digestibility was not included in these estimates.
Results
    Our analysis was based on 99 high-CO2 experiments and 48 
crops, and it included 54 field experiments. Of the 64 experimental 
sites, 37 were elsewhere than Europe or North America (see Table S1).
    In maize, peas, and mustard seed, we found a linear dose response 
when the RR of protein content was compared with the degree of 
CO2 elevation above ambient (see Tables S1 and S2). 
Metaregression for other crops was not significant, partly because of 
insufficient statistical power. Maize protein content under 
eCO2 was not significantly below that under aCO2 
when considered overall from meta-analyses or when predicted for an 
atmospheric CO2 increase of 150 ppm from metaregression. 
Metaregression predicted a decrease in pea protein content of 4.1% 
(1.6-6.7%) with an atmospheric CO2 increase of 150 ppm, and 
overall, meta-analyses showed no significant declines in pea protein. 
National changes in dietary protein content were on average 0.04% less 
when modeled for a 150 ppm increase in atmospheric CO2 based 
on metaregression results compared with meta-analyses. This difference 
was small enough to warrant the use of meta-analyses rather than 
metaregression. Comparisons between field and pot-based experiments, 
and between nitrogen fertilizer treatments were largely nonsignificant 
(p>0.05; see Table S2).
    Meta-analyses confirmed lower protein content of C3 
grains (including barley, 14.1% lower), tubers (including potato, 6.4% 
lower), fruit (23.0% lower), and vegetables (17.3% lower) under 
eCO2, with no significant change in the protein content of 
C4 grains, nitrogen-fixing pulses, or oil crops (Table 1).
    When these effect sizes were translated to FBS-standardized 
commodity intakes, the mean protein intake decreased under 
eCO2 by >5% in 18 countries, including India, Bangladesh, 
Turkey, Egypt, Iran, and Iraq. Particularly large declines are expected 
through the Middle East and India, where a 5.3% decrease in dietary 
protein is predicted (Table 2, Figure 1).

                   Table 2. Change in dietary protein.
------------------------------------------------------------------------
                                       Mean change in     Difference in
                    Mean change in     protein intake    protein-energy
     Region         protein intake    (%), plant-based     ratio (aCO2
                         (%)                diet         minus eCO2, %)
------------------------------------------------------------------------
          CALACA   ^1.99 (^3.61,      ^4.03 (^6.64,      ^0.20 (^0.37,
                          ^0.36)             ^1.42)             ^0.04)
      CANAME       ^5.04 (^7.29,     ^7.87 (^10.88,      ^0.52 (^0.75,
                          ^2.79)             ^4.85)             ^0.29)
      CEEAEU       ^3.43 (^4.90,      ^8.19 (^10.6,      ^0.39 (^0.55,
                          ^1.97)             ^5.77)             ^0.22)
      CHINAR       ^4.91 (^6.06,      ^8.86 (^10.4,      ^0.57 (^0.71,
                          ^3.75)             ^7.32)             ^0.44)
      ESEASP       ^4.01 (^5.51,      ^6.78 (^8.96,      ^0.36 (^0.50,
                          ^2.52)             ^4.59)             ^0.23)
      HIGHIN       ^2.67 (^3.65,      ^7.95 (^9.91,      ^0.32 (^0.43,
                          ^1.68)             ^5.98)             ^0.20)
       India       ^5.34 (^7.02,      ^7.04 (^9.02,      ^0.47 (^0.61,
                          ^3.66)             ^5.05)             ^0.32)
      SOASIA       ^4.69 (^6.44,      ^7.11 (^9.40,      ^0.43 (^0.59,
                          ^2.94)             ^4.82)             ^0.27)
        SOTRLA     ^2.40 (^3.46,      ^6.18 (^8.14,      ^0.27 (^0.38,
                          ^1.34)             ^4.22)             ^0.15)
      SUSAAF       ^2.03 (^4.05,      ^2.71 (^5.13,      ^0.18 (^0.36,
                          ^0.01)             ^0.30)              0.00)
       World       ^3.93 (^5.15,      ^7.14 (^8.91,      ^0.41 (^0.53,
                          ^2.70)             ^5.37)             ^0.28)
------------------------------------------------------------------------
Note: Figures represent population-weighted averages (and 95% confidence
  intervals) globally and for each region (2050 populations). Protein-
  energy ratio is the percentage of dietary energy (calories) that is
  derived from protein. CALACA, Central and Andean Latin America and the
  Caribbean; CANAME, Central Asia, North Africa and the Middle East;
  CEEAEU, Central and Eastern Europe; CHINAR, Greater China; ESEASP,
  East and Southeast Asia and the Pacific excluding China; HIGHIN, high
  income countries; SOASIA, South Asia excluding India; SOTRLA, Southern
  and Tropical Latin America; SUSAAF, sub-Saharan Africa. See Table S4
  for country grouping.

Figure 1
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

          Per-country change in dietary protein intake under elevated 
        carbon dioxide [eCO2 (%)]. Baseline intake is based 
        on Food and Agriculture Organisation of the United Nations Food 
        Balance Sheets (FAO FBS) estimates, and changes are calculated 
        from decreases in protein content in the edible portions of 
        crops when grown under eCO2. Data were plotted using 
        the Rworldmap package in R (version 3.2.4; R Development Core 
        Team).

    Globally, >7% decreases in protein intake are predicted for plant-
based diets under eCO2, with countries dependent on 
C3 staples particularly affected (Table 2), including 
Central Asia, North Africa and the Middle East (7.9%), Central and 
Eastern Europe (8.2%), and China (8.9%).A significant positive linear 
relationship existed between the natural log of CVprotein 
and income-based Gini coefficients (slope 0.026, p<0.0001; Figure 2). 
Income inequality explained half of within-country variation in protein 
intake (r\2\=0.49).
Figure 2
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

          Coefficient of variation in protein intake derived from 
        household surveys plotted against the income-based Gini 
        coefficient for the year closest to the year household surveys 
        were conducted (slope 0.026, p<0.0001).

    Estimates indicated a 12.2% current risk of protein deficiency 
globally. With constant atmospheric CO2 concentrations, we 
predict that globally, 15.1% or 1.4 billion people will be at risk of 
protein deficiency by 2050 because of demographic changes. This 
estimate includes 613.6 million people at risk in sub-Saharan Africa, 
276.4 million in India, 131.7 million in Eastern and Southeast Asia and 
the Pacific, 84.4 million in Central Latin America and the Caribbean, 
and 77.8 million elsewhere in South Asia (Figure 3, Table 3).
Figure 3
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

          Risk of protein deficiency as defined by protein intake below 
        estimated average protein requirements (EAR). Estimates of (A) 
        current percentage of the population at risk of deficiency, (B) 
        percent of the population newly at risk of deficiency under 
        elevated carbon dioxide (eCO2), and (C) millions of 
        people estimated to be newly at risk of deficiency under 
        eCO2, based on 2050 population projections. Data 
        were plotted using the Rworldmap package in R (version 3.2.4; R 
        Development Core Team).

  Table 3. Populations at risk of protein deficiency under aCO2 and eCO2 (population-weighted averages and 95%
                                              confidence intervals)
----------------------------------------------------------------------------------------------------------------
                                                              At risk of
                           At risk of     Difference in      deficiency in
             EAR, 2050      protein       protein-energy   2050, aCO2 (%)At    Additionally at   Additionally at
   Region      (g/d)      deficiency,      ratio (aCO2    risk of deficiency   risk with eCO2:   risk with eCO2:
                            aCO2 (%)      minus eCO2, %)     in 2050, aCO2        2050 (%)       2050 (millions)
                                                              (millions)
----------------------------------------------------------------------------------------------------------------
      CALACA   30.49    17.05 (11.64,     18.4 (12.84,       84.37 (58.90,       0.86 (0.57,       3.94 (2.64,
                               24.65)           25.64)             117.61)             1.19)             5.46)
  CANAME       31.46      6.22 (4.00,      7.32 (4.88,        57.2 (38.09,       1.53 (1.14,      11.97 (8.93,
                                9.32)           10.46)              81.71)             1.94)            15.12)
  CEEAEU       33.44      3.58 (1.40,      3.52 (1.37,    9.64 (3.74, 26.77)     0.56 (0.27,       1.52 (0.73,
                                9.84)            9.79)                                 0.95)             2.61)
  CHINAR       31.68      5.25 (0.16,      5.38 (0.16,    74.96 (2.27, 297)      1.14 (0.11,      15.94 (1.47,
                               21.01)           21.31)                                 2.04)            28.45)
  ESEASP       29.47     15.35 (9.59,     15.79 (9.68,      131.67 (80.71,       1.92 (1.40,     15.99 (11.68,
                               22.78)           23.56)             196.44)             2.43)            20.28)
  HIGHIN       33.05      2.62 (1.01,       2.6 (0.99,       28.39 (10.83,       0.31 (0.16,       3.41 (1.75,
                                6.86)            7.36)              80.47)             0.53)             5.78)
   India       30.06     16.27 (3.73,     17.06 (4.46,      276.42 (72.32,       3.30 (1.93,     53.41 (31.22,
                               32.49)           33.36)             540.41)             4.55)            73.71)
  SOASIA       30.41     13.23 (6.15,     13.74 (6.91,       77.76 (39.10,       2.80 (1.88,     15.86 (10.64,
                               21.98)           22.59)             127.88)             3.74)            21.20)
    SOTRLA     31.35     11.46 (2.80,     12.03 (3.25,       38.14 (10.30,       0.68 (0.26,       2.17 (0.81,
                               27.14)           27.40)              86.87)             1.07)             3.39)
  SUSAAF       30.53    27.12 (23.07,    28.89 (24.73,     613.56 (525.07,       1.16 (0.73,     24.64 (15.44,
                               31.46)           33.44)             710.24)             1.59)            33.83)
   World       30.99     12.18 (9.07,    15.06 (12.11,    1424.59 (1145.89,      1.57 (1.26,    148.37 (119.06,
                               16.32)           18.71)            1770.20)             1.86)           176.09)
----------------------------------------------------------------------------------------------------------------
Note: Calculations use 2011 populations and 2050 population projections. aCO2, ambient atmospheric carbon
  dioxide; CALACA, Central and Andean Latin America and the Caribbean; CANAME, Central Asia, North Africa and
  the Middle East; CEEAEU, Central and Eastern Europe; CHINAR, Greater China; EAR, estimated average protein
  requirement based on 2050 demographic projections; eCO2 elevated atmospheric carbon dioxide; ESEASP, East and
  Southeast Asia and the Pacific excluding China; HIGHIN, high income countries; SOASIA, South Asia excluding
  India; SOTRLA, Southern and Tropical Latin America; SUSAAF, sub-Saharan Africa. See Table S4 for country
  grouping.

    With predicted atmospheric CO2 concentrations >500ppm by 
2050, we estimate an additional 1.57% of the world's population (148.4 
million) will be at risk of protein deficiency, compared with 2050 
aCO2 scenarios. In particular, an additional 53.4 million 
people in India, 15.9 million elsewhere in South Asia and 24.6 million 
in sub-Saharan Africa are estimated to become newly at risk (Table 3, 
Figure 3). An additional 15.9 million people in the China region and 
12.0 million in Central Asia, North Africa, and the Middle East are 
expected to become at risk with eCO2. The greatest increases 
in percent at risk of protein deficiency are expected in Tajikistan, 
Bangladesh, Burundi, Liberia, Occupied Palestinian Territory, Iraq, and 
Afghanistan (Figure 3B).
    Globally, we predict the protein-energy ratio (protein caloric 
contribution as a percent of total calories) to decrease under 
eCO2 by 0.41%; in individual countries and regions, we 
predict this ratio to decrease by 0.6% in 17 counties including China, 
Iran, Iraq, Morocco, and Turkey. We expect decreases in China of 0.57% 
(Table 2).
Discussion
    Our study highlights the potential impact of eCO2 on 
dietary protein intake globally. Wheat and rice, among the most 
sensitive crops to eCO2, are primary protein sources for 71% 
of the world's population (FAO 2014a). By 2050, 148.4 million people 
worldwide may become at risk of protein deficiency from rising 
CO2. In India, expected to be the world's most populous 
country (UN 2013), and a country that is highly dependent on rice, 53.4 
million people may be newly at risk of protein deficiency. 
Additionally, the protein deficiency in roughly 1.4 billion people 
globally (predicted under aCO2 in 2050) is anticipated to 
become more severe under eCO2 scenarios. Although estimates 
of current protein intake and income inequality highlight the current 
risk of deficiency in sub-Saharan Africa and South America, their 
dependence on less-sensitive C4 crops make these diets less 
sensitive to eCO2.
    Importantly, we incorporated into the risk assessment different 
distributions of protein intake in countries based on income inequality 
from the association of income-based Gini coefficients with variability 
in protein intake from national dietary surveys. We find it equally 
plausible that CVprotein would decrease or increase by 2050. 
We therefore provide the most conservative estimate of future protein 
intake distributions, namely that CVprotein within countries 
will remain unchanged. We also assume unchanged duration and prevalence 
of breastfeeding, and unchanged adult height.
    Although our calculations assume no change in the shape of the 
intake distribution, we anticipate a worsening of inequality in protein 
intake within populations because a larger decrease in protein content 
is observed in plant-based than in omnivore diets under eCO2 
(Table 2). Some changes in meat quality are anticipated owing to 
increased fat content under lower-protein diets (Blome, et al., 2003), 
but this is likely to be negligible compared with the effects on plant-
based protein sources. Those who consume the least protein have diets 
more dependent on plant protein, and these people are more vulnerable 
to eCO2 effects on plant protein. This is likely to extend 
the lower tail of the intake distribution, increasing the severity and 
prevalence of protein inadequacy. Our estimates are worst-case 
scenarios where no substitution of animal-sourced protein sources for 
other high-protein foods is allowed. In particular, the predicted large 
decreases in protein content of plant-based diets in high income 
countries may be overestimates, where plant-based diets are likely to 
be supplemented with other protein sources.
    The countries that we estimated to be currently most at risk of 
protein deficiency are also those with the greatest estimated 
prevalence of undernourishment (FAO 2014b), increasing confidence in 
our estimates; however, energy balance and nitrogen balance interact 
(Garza, et al., 1976). For simplicity, we modeled overall protein 
intake and risk of deficiency based on the EAR, which assumes adequate 
energy intake. Published EARs are defined for zero protein balance, 
which is a conservative estimate of protein requirements (IOM 2005). 
Older, sedentary people and those suffering from or recovering from 
illness are likely to be at greater risk of deficiency in any 
population (Ghosh 2013). We have not accounted for current or future 
patterns of illness in our estimates of EAR. Furthermore, we have not 
considered changes in protein quality; however, several studies have 
shown that essential amino acids tend to be relatively preserved at the 
expense of nonessential amino acids under eCO2, and 
degradability may decrease (Hogy, et al,. 2009; Wroblewitz, et al., 
2013). Bioavailability may change, for example, if meal composition and 
thus digestibility changes. Furthermore, levels of secondary 
metabolites, including toxins, tend to increase under elevated 
CO2 (Cavagnaro, et al., 2011), which could decrease protein 
bioavailability.
    In addition to increasing the risk of protein deficiency, there may 
be other nutritional consequences of changing the stoichiometry of 
carbohydrate-to-protein ratios in staple food crops. For example, 
replacing dietary carbohydrate with protein has been shown in 
interventional trials and observational studies to 15-y duration, and 
in diverse countries including Japan, China, the United States, and 
Chile, to improve cardiovascular disease risk through lowering blood 
pressure and changing lipid profiles (Hu, et al., 1999; Obarzanek, et 
al., 1996; Appel, et al., 2005; Altorf-van der Kuil, et al., 2010; 
Rebholz, et al., 2012). Improvements are often greatest with plant--
rather than animal-sourced protein (Altorf-van der Kuil, et al., 2010). 
These experiments underscore the need for additional investigation into 
whether replacing plant-sourced protein with plant-sourced carbohydrate 
could exacerbate the already concerning pandemic of metabolic disease 
driving increased cardiovascular morbidity and mortality globally.
    It is unclear how trends in dietary quality will be counterbalanced 
by the effects of population growth and climate change. That is why, 
for our analysis, we assume no future change to food composition of 
diets or to per capita food intake and no dietary substitution to 
compensate for deficits. Agricultural production will need to roughly 
double to match increasing demand by 2050 (Alexandratos 1999). Climate 
change may pose the greatest challenge to this need. Climate change-
induced reductions in crop yield are expected to be greatest in lower-
latitude regions, including developing countries and those dependent on 
C4 crops (Rosenzweig, et al., 2014). Resulting economic 
changes may shape future diets, and changes to water, soils, and 
weather in these areas may affect crops in ways that may overwhelm, or 
exacerbate, the effects of eCO2. For example, decreases in 
yield under drought and warming temperatures may counteract the effects 
of rising CO2 on protein concentrations (Kimball, et al., 
2001). Only 37 of 99 study sites in our meta-analysis were in countries 
outside of Europe and North America, and only just over half of the 
studies were performed in the field, with only 10% involving watering 
experiments (see Table S1). Most experiments were undertaken over 1 y 
only, and effects on crop nutrient content may not match those under 
the next 50 y of gradual atmospheric CO2 increase. The 
consistent decreases in protein contents across C3 crop 
cultivars, including 47 wheat cultivars and 27 rice cultivars, reassure 
us that our results are generalizable to other cultivars. Nevertheless, 
to better predict the dietary impacts of eCO2, we need more 
long-term field-based eCO2 experiments involving plants and 
cultivars grown under the climates and farming practices applicable to 
the developing world.
    We also assumed that global population growth and future 
demographic trends will match UN projections, which include declining 
fertility rates, and migration from developing to developed countries 
(UN 2013). However, the greatest population growth is projected to 
occur in areas most vulnerable to climate change (Watts, et al., 2015). 
Climate, economic, and demographic changes will likely interact, 
producing a global population distribution that we are not yet able to 
fully comprehend. In the absence of conclusive projections of future 
food production, we believe it is the most conservative, albeit perhaps 
optimistic, assumption that per capita food intake will remain constant 
despite sharp increases in global demand.
    In predicting the nutritional consequences of eCO2, 
other nutrients must be considered. Zinc and iron concentrations are 
greatly decreased in C3 plants grown under eCO2 
(Myers, et al., 2014). Zinc is a cofactor for protein synthesis, and 
protein inadequacy decreases uptake and availability of other nutrients 
(Gropper and Smith 2008). A recent analysis predicts strong increases 
in the risk of global zinc deficiency with eCO2 (Myers, et 
al., 2015). Identifying the countries most vulnerable to future 
malnutrition requires a targeted synthesis of crop research on climate 
and CO2 responses. This information can then be applied to 
global climate and atmospheric models.
    To our knowledge, this is the first global comparison of dietary 
protein that estimates a country-specific CV. Like energy consumption, 
the variability of protein consumption in a population relates to the 
Gini coefficient (Raubenheimer, et al., 2015). Our use of this metric 
would be expected to produce more accurate estimates than the 
previously used 25% CV (Ghosh 2013). The WHO continues to refine its 
models of energy intake variability based on gross domestic product 
(GDP), Gini, and food prices, using skew log rather than lognormal 
distributions. As this methodology becomes available, future work could 
incorporate these considerations to produce better estimates of protein 
consumption.
    Because added fertilizer did not predictably mitigate the effects 
of CO2 on crop protein, and with the production and 
application of fertilizer being a principal contributor to agricultural 
greenhouse gas emissions (Vermeulen, et al., 2012), we cannot simply 
add more fertilizer to reduce the protein deficit. As populations 
increase, and with livestock production being resource-intensive 
(Vermeulen, et al., 2012), eating more meat is not a practical 
solution. Cultivars could be selected or bred based on their 
nutritional content under eCO2. In addition to efforts to 
mitigate CO2 emissions, nutritious and resilient crops 
should be promoted, for example legumes, which will withstand the 
effects of eCO2 on protein content. Because eCO2 
may have the greatest effect on the protein intake of those with the 
poorest diets, more equitable food distribution, and poverty reduction 
measures should be a focus for minimizing risk of deficiency.
Conclusions
    Anthropogenic CO2 emissions, via their impact on the 
protein content of C3 staples, may threaten the adequacy of 
protein intake for many populations. Although quantifying protein 
deficiency is notoriously difficult, we have estimated current and 
future risk of protein deficiency by country and region, suggesting 
enduring challenges for sub-Saharan Africa and growing challenges for 
South Asia, including India. For nutritionally sensitive agriculture, 
the high CO2 effects on crop nutrient contents must be 
incorporated into future food security policies.
Acknowledgments
    We thank A. Fangmeier for additional data generously shared, M. 
Smith for valuable comments and data, M. Stefan and R. Wessells for 
statistical advice, W. Willett for help with project conception, the 
Harvard University Center for the Environment for hosting D.E.M., and 
C. Hotz for her insights into the literature on protein deficiency.
    Financial support was provided by the Bill & Melinda Gates 
Foundation and by the Winslow Foundation. Funding sources had no input 
into study design, data collection, analysis, data interpretation, 
report writing, or decision to submit the manuscript for publication.

 
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                               Article 2
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[https://fireecology.springeropen.com/articles/10.1186/s42408-019-0062-
8]
Fire Ecology
Changing wildfire, changing forests: the effects of climate change on 
        fire regimes and vegetation in the Pacific Northwest, USA
Jessica E. Halofsky * \1\, David L. Peterson \2\ and Brian J. Harvey 
\2\
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    * Correspondence: [email protected].
    \1\ U.S. Department of Agriculture, Forest Service, Pacific 
Northwest Research Station, Olympia Forestry Sciences Lab, 3625 93rd 
Avenue SW, Olympia, Washington 98512, USA.
    \2\ School of Environmental and Forest Sciences, College of the 
Environment, University of Washington, Box 352100, Seattle, Washington 
98195-2100, USA.
     The Author(s). 2020 Open Access This 
article is licensed under a Creative Commons Attribution 4.0 
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will need to obtain permission directly from the copyright holder. To 
view a copy of this licence, visit http://creativecommons.org/licenses/
by/4.0/.
    Full list of author information is available at the end of the 
article.
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Abstract
    Background: Wildfires in the Pacific Northwest (Washington, Oregon, 
Idaho, and western Montana, USA) have been immense in recent years, 
capturing the attention of resource managers, fire scientists, and the 
general public. This paper synthesizes understanding of the potential 
effects of changing climate and fire regimes on Pacific Northwest 
forests, including effects on disturbance and stress interactions, 
forest structure and composition, and post-fire ecological processes. 
We frame this information in a risk assessment context, and conclude 
with management implications and future research needs.
    Results: Large and severe fires in the Pacific Northwest are 
associated with warm and dry conditions, and such conditions will 
likely occur with increasing frequency in a warming climate. According 
to projections based on historical records, current trends, and 
simulation modeling, protracted warmer and drier conditions will drive 
lower fuel moisture and longer fire seasons in the future, likely 
increasing the frequency and extent of fires compared to the twentieth 
century. Interactions between fire and other disturbances, such as 
drought and insect outbreaks, are likely to be the primary drivers of 
ecosystem change in a warming climate. Reburns are also likely to occur 
more frequently with warming and drought, with potential effects on 
tree regeneration and species composition. Hotter, drier sites may be 
particularly at risk for regeneration failures.
    Conclusion: Resource managers will likely be unable to affect the 
total area burned by fire, as this trend is driven strongly by climate. 
However, fuel treatments, when implemented in a spatially strategic 
manner, can help to decrease fire intensity and severity and improve 
forest resilience to fire, insects, and drought. Where fuel treatments 
are less effective (wetter, high-elevation, and coastal forests), 
managers may consider implementing fuel breaks around high-value 
resources. When and where post-fire planting is an option, planting 
different genetic stock than has been used in the past may increase 
seedling survival. Planting seedlings on cooler, wetter microsites may 
also help to increase survival. In the driest topographic locations, 
managers may need to consider where they will try to forestall change 
and where they will allow conversions to vegetation other than what is 
currently dominant.
    Keywords: adaptation, climate change, disturbance regimes, drought, 
fire regime, Pacific Northwest, regeneration, vegetation.
Resumen
    Antecedentes: Los incendios de vegetacion en el Noroeste del 
pacifico (Washington, Oregon, Idaho, y el oeste de Montana, EEUU), han 
sido inmensos en anos recientes, capturando la atencion de los gestores 
de recursos, de cientificos dedicados a los incendios, y del publico en 
general. Este trabajo sintetiza el conocimiento de los efectos 
potenciales del cambio climatico y de los regimenes de fuego en bosques 
del noroeste del Pacifico, incluyendo los efectos sobre las 
interacciones entre disturbios y distintos estreses, la estructura y 
composicion de los bosques, y los procesos ecologicos posteriores. 
Encuadramos esta informacion en el contexto de la determinacion del 
riesgo, y concluimos con implicancias en el manejo y la necesidad de 
futuras investigaciones.
    Resultados: Los incendios grandes y severos en el Noroeste del 
Pacifico estan asociados con condiciones calurosas y secas, y tales 
condiciones muy probablemente ocurran con el incremento en la 
frecuencia del calentamiento global. De acuerdo a proyecciones basadas 
en registros historicos, tendencias actuales y modelos de simulacion, 
condiciones prolongadas de aumento de temperaturas y sequias conduciran 
a menores niveles de humedad, incrementando probablemente la frecuencia 
y extension de fuegos en el futuro, en comparacion con lo ocurrido 
durante el siglo XX. Las interacciones entre el fuego y otros 
disturbios, son probablemente los principales conductores de cambios en 
los ecosistemas en el marco del calentamiento global. Los incendios 
recurrentes podrian ocurrir mas frecuentemente con aumentos de 
temperatura y sequias, con efectos potenciales en la regeneracion de 
especies forestales y en la composicion de especies. Los sitios mas 
calidos y secos, pueden estar particularmente en riesgo por fallas en 
la regeneracion.
    Conclusiones: Los gestores de recursos no podrian tener ningun 
efecto sobre el area quemada, ya que esta tendencia esta fuertemente 
influenciada por el clima. Sin embargo, el tratamiento de combustibles, 
cuando esta implementado de una manera espacialmente estrategica, puede 
ayudar a reducir la intensidad y severidad de los incendios, y mejorar 
la resiliencia de los bosques al fuego, insectos, y sequias. En lugares 
en los que el tratamiento de combustibles es menos efectivo (areas mas 
humedas, elevadas, y bosques costeros) los gestores deberian considerar 
implementar barreras de combustible alrededor de valores a proteger. 
Cuando y donde la plantacion post fuego sea una opcion, plantulas 
provenientes de diferentes stocks geneticos de aquellos que han sido 
usados en el pasado pueden incrementar su supervivencia. La plantacion 
de plantulas en micrositios mas humedos y frios podria ayudar tambien a 
incrementar la supervivencia de plantulas. En ubicaciones topograaficas 
mas secas, los gestores deberian considerar evitar cambios y donde 
estos sean posibles, permitir conversiones a tipos de vegetacion 
diferentes a las actualmente dominantes.
Abbreviations
          ENSO: El Nino-Southern Oscillation
          MPB: Mountain Pine Beetle
          PDO: Pacific Decadal Oscillation
Introduction
    Large fires are becoming a near-annual occurrence in many regions 
globally as fire regimes are changing with warming temperatures and 
shifting precipitation patterns. The U.S. Pacific Northwest (states of 
Washington, Oregon, Idaho, and western Montana, USA; hereafter the 
Northwest) is no exception. In 2014, the largest wildfire in recorded 
history for Washington State occurred, the 103 640 ha Carlton Complex 
Fire (Fig. 1). In 2015, an extreme drought year with very low snowpack 
across the Northwest (Marlier, et al., 2017), 688 000 ha burned in 
Oregon and Washington (Fig. 2), with over 3.6 million ha burned in the 
western United States. Several fires in 2015 occurred in conifer 
forests on the west (i.e., wet) side of the Cascade Range, including a 
rare fire event in coastal temperate rainforest on the Olympic 
Peninsula. In some locations, short-interval reburns have occurred. For 
example, one location on Mount Adams in southwestern Washington burned 
three times between 2008 and 2015 (Fig. 3). Similarly, during the 
summer of 2017 in southwestern Oregon, the 77 000 ha Chetco Bar Fire 
burned over 40 000 ha of the 2002 Biscuit Fire, including a portion of 
the Biscuit Fire that had burned over part of the 1987 Silver Fire. At 
over 200 000 ha, the Biscuit Fire was the largest fire in the recorded 
history of Oregon.
Fig. 1
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          Large wildfires, such as the 2014 Carlton Complex Fire in 
        Washington, USA (103 640 ha), have occurred throughout western 
        North America during the past several decades. These 
        disturbances have a significant effect on landscape pattern and 
        forest structure and will likely become more common in a warmer 
        climate, especially in forests with heavy fuel loadings. Photo 
        credit: Morris Johnson.
Fig. 2
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          Fires burning across the Pacific Northwest, USA, on 25 August 
        2015. This natural-color satellite image was collected by the 
        Moderate Resolution Imaging Spectroradiometer (MODIS) aboard 
        the Aqua satellite. Actively burning areas, detected by MODIS's 
        thermal bands, are outlined in red. National Aeronautics and 
        Space Administration image courtesy of Jeff Schmaltz, MODIS 
        Rapid Response Team.
Fig. 3a
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Fig. 3b
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          (a) Large fires around Mount Adams in Gifford Pinchot 
        National Forest in southwestern Washington, USA, between 2001 
        and 2015 (area in orange burned twice, and area in red burned 
        three times); and (b) area in Gifford Pinchot National Forest 
        that has burned three times since 2008 (2008 Cold Springs fire, 
        2012 Cascade Creek fire, and 2015 Cougar Creek fire). Map 
        credit: Robert Norheim; photo credit: Darryl Lloyd.

    Over the twentieth century in the Northwest, years with relatively 
warm and dry conditions have generally corresponded with larger fires 
and greater area burned (Trouet, et al., 2006; Westerling, et al., 
2006; Littell, et al., 2009; Littell, et al., 2010; Abatzoglou and 
Kolden 2013; Cansler and McKenzie 2014; Dennison, et al., 2014; 
Stavros, et al., 2014; Westerling 2016; Kitzberger, et al., 2017; 
Reilly, et al., 2017; Holden, et al., 2018). Decreasing fuel moisture 
and increasing duration of warm, dry weather creates large areas of dry 
fuels that are more likely to ignite and carry fire over a longer 
period of time (Littell, et al., 2009).
    A warming climate will have profound effects on fire frequency, 
extent, and possibly severity in the Northwest. Increased temperatures 
are projected to lengthen fire and growing seasons, increase 
evaporative demand, decrease soil and fuel moisture, increase 
likelihood of large fires, and increase area burned by wildfire 
(McKenzie, et al., 2004; Littell, et al., 2010; Stavros, et al., 2014; 
Westerling 2016). Decreased summer precipitation is also projected to 
increase area burned (Holden, et al., 2018).
    Interactions between fire and other disturbance agents (e.g., 
drought, insect outbreaks) will likely catalyze ecosystem changes in a 
warming climate. Increased tree stress and interacting effects of 
drought may also contribute to increasing wildfire severity (damage to 
vegetation and soils) and area burned (McKenzie, et al., 2009; Stavros, 
et al., 2014; Littell, et al., 2016; Reilly, et al., 2017).
    Climatic changes and associated stressors can interact with altered 
vegetation conditions (e.g., those resulting from historical management 
practices) to affect fire frequency, extent, and severity, as well as 
forest conditions in the future (Keeley and Syphard 2016). Human 
influence through domestic livestock grazing, road construction, 
conversion of land to agriculture, and urbanization has resulted in 
(direct or indirect) exclusion of fires in dry forests (Hessburg, et 
al., 2005). Many larger, fire-resistant trees have been removed by 
selective logging. These activities, along with active fire 
suppression, have resulted in increased forest density and fuel buildup 
in forests historically characterized by frequent, low-severity and 
mixed-severity fires (Hessburg, et al., 2005). Although landscape 
pattern and fuel limitations were key factors that limited fire size 
and severity historically, these limitations have been largely removed 
from many contemporary landscapes, thus increasing the potential for 
large high-severity fires, particularly in a warming climate.
    Facing such changes, land managers need information on the 
magnitude and likelihood of altered fire regimes and forest conditions 
in a warming climate to help guide long-term sustainable resource 
management. Many published studies have explored the potential effects 
of climate change on forest fire in the Northwest, including 
paleoecological, modeling, and local- to regional-scale empirical 
studies. However, to our knowledge, there is no single resource that 
synthesizes these varied studies for the Northwest region. A synthesis 
of this information can help managers better understand the potential 
effects of climate change on ecosystem processes, assess risks, and 
implement actions to reduce the negative effects of climate change and 
transition systems to new conditions.
    In this synthesis, we draw from relevant published literature to 
discuss potential effects of changing climate on fire frequency, 
extent, and severity in Northwest forests. Sources of information 
include: (1) long-term (centuries to millennia) paleoecological studies 
of climate, fire, and species distribution; (2) medium-term (decades to 
centuries) fire history studies; (3) near-term (years to decades) 
studies on trends in vegetation and fire associated with recent 
climatic variability and change; (4) forward-looking studies using 
simulation models to project future fire and vegetation change; and (5) 
recent syntheses focused on potential climate change effects.
    We used regionally specific information where possible, including 
information from adjacent regions with forests of similar structure and 
function when relevant. Following an overview of climate projections, 
we (1) identified risks related to wildfire as affected by climate 
change in three broad ecosystem types; (2) explored the magnitude and 
likelihood of those risks; and (3) concluded with a discussion of 
uncertainties about future climate and fire, potential future research, 
and implications for resource management.
Overview of climate projections
    Warming temperatures and changing precipitation patterns will 
affect amount, timing, and type of precipitation; snowmelt timing and 
rate (Luce, et al., 2012; Luce, et al., 2013; Safeeq, et al., 2013); 
streamflow magnitude (Hidalgo, et al., 2009; Mantua, et al., 2010); and 
soil moisture content (McKenzie and Littell 2017). Compared to the 
historical period from 1976 to 2005, 32 global climate models project 
increases in mean annual temperature for the middle and end of the 
twenty-first century in the Northwest. These projected increases range 
from 2.0 to 2.6 C for mid-century (2036 to 2065) and 2.8 to 4.7 C for 
the end of the century (2071 to 2100), depending on future greenhouse 
gas emissions (specifically representative concentration pathway 4.5 or 
8.5; Vose, et al., 2017). Warming is expected to occur during all 
seasons, although most models project the largest temperature increases 
in summer (Mote, et al., 2014). All models suggest a future increase in 
heat extremes (Vose, et al., 2017).
    Changes in precipitation are less certain than those for 
temperature. Global climate model projections for annual average 
precipitation range from ^4.7 to +13.5%, averaging about +3% among 
models (Mote, et al., 2014). A majority of models project decreases in 
summer precipitation, but projections for precipitation vary for other 
seasons. However, models agree that extreme precipitation events (i.e., 
number of days with precipitation >2.5 cm) will likely increase, and 
that the length of time between precipitation events will increase 
(Mote, et al., 2014; Easterling, et al., 2017).
Risk assessment
    A risk-based approach to climate change vulnerability assessments 
provides a common framework to evaluate potential climate change 
effects and identify a structured way to choose among adaptation 
actions or actions to mitigate climate change risks (EPA 2014). Risk 
assessment is linked with risk management by (1) identifying risks--
that is, how climate change may prevent an agency or other entity from 
reaching its goals; (2) analyzing the potential magnitude of 
consequences and likelihood for each risk; (3) selecting a set of risk-
reducing actions to implement; and (4) prioritizing those actions that 
address risks with the highest likelihood and magnitude of consequences 
(EPA 2014).
    Here, we summarized potential risks that are relevant for natural 
resource management associated with climate-fire interactions, 
including: wildfire frequency, extent, and severity; reburns; stress 
interactions; and regeneration for (1) moist coniferous forest (low to 
mid elevation), (2) dry coniferous forest and woodland (low to mid 
elevation), and (3) subalpine coniferous forest and woodland (high 
elevation). The likelihood and magnitude of consequences, and 
confidence in inferences are described for each risk. Although the 
information provided here does not constitute risk management, as 
described in the previous paragraph, this information can be used to 
inform more site- and resource-specific risk assessments and risk 
management.
    The risks identified here were inferred from the authors' review of 
the published literature described below, as well as experience with 
developing climate change vulnerability assessments in the study region 
over the past decade (Halofsky, et al., 2011a, b; Raymond, et al., 
2014; Halofsky and Peterson 2017a, b; Halofsky, et al., 2019; Hudec, et 
al., 2019). These assessments encompassed all ecosystems and species 
addressed in this synthesis, and included extensive discussion of the 
effects of wildfire and other disturbances. Climate change effects and 
adaptation options in the assessments were greatly informed by input 
from resource managers as well as by scientific information. Thus, many 
fire-related vulnerabilities identified in the assessments are relevant 
to the risk assessment discussed here.
Risk in moist coniferous forests
    Most climate-fire risks in moist coniferous forests are relatively 
low (Table 1). These forests occur west of the Cascade Range in Oregon 
and Washington and are frequently dominated by Douglas-fir 
(Pseudotstuga menziesii [Mirb.] Franco) and western hemlock (Tsuga 
heterophylla [Raf.] Sarg.). Moist coniferous forests are characterized 
by an infrequent, stand-replacing (i.e., high-severity) fire regime 
(Agee 1993). Although fire frequency and severity may increase with 
climate change, the frequency of fire in these moist ecosystems will 
likely remain relatively low.

                                 Table 1
 
   Risk assessment for the effects of fire-climate interactions in moist
 coniferous forest, low to mid elevation (Olympics, west-side Cascades,
  northern Idaho, west-side Rocky Mountains, USA), for the mid to late
twenty-first century. Likelihood and confidence are rated low, moderate,
   and high. Low likelihood represents consequences that are unlikely
  (approximately 0 to 33% probability), moderate likelihood represents
  consequences that are about as likely as not (approximately 33 to 66%
probability), high likelihood represents consequences that are likely to
  very likely (approximately 66 to 100% probability). Low confidence is
 characterized by low scientific agreement and limited evidence, whereas
high confidence is characterized by high scientific agreement and robust
  evidence, with moderate confidence falling between those two extremes
 
-------------------------------------------------------------------------
   Fire-climate       Magnitude of      Likelihood of
   interaction        consequences       consequences       Confidence
------------------------------------------------------------------------
Wildfire           Small increase     Low                High
 frequency
Wildfire extent    Small increase     Low                Moderate
Wildfire severity  No change to       Low                Moderate
                    small increase
Reburns            No change to       Low                Moderate
                    small increase
Stress             Small increase     Low to moderate    Moderate
 interactions
Regeneration       No change to       Low                Low
                    small decrease
------------------------------------------------------------------------

Risk in dry coniferous forests
    Climate-fire risks in dry coniferous forests and woodlands are high 
for increased fire frequency, extent, and severity (Table 2). Dry 
coniferous forests and woodlands occur at lower elevations in 
southwestern Oregon, east of the Cascade Range in Oregon and 
Washington, and at lower elevations in the Rocky Mountains in Idaho and 
Montana. Fire regimes in these forests and woodlands range from 
moderate frequency and mixed severity to frequent and low severity. 
Ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) is a 
characteristic species, along with Douglas-fir, grand fir (Abies 
grandis [Douglas ex D. Don] Lindl.), and white fir (Abies concolor 
[Gordon & Glend.] Lindl. ex Hildebr.). These forests and woodlands are 
also at risk from interacting disturbances and hydrologic change 
(moderate to high likelihood and magnitude of consequences), and post-
fire regeneration failures are likely to occur on some sites.

                                 Table 2
 
    Risk assessment for the effects of fire-climate interactions in dry
    coniferous forest and woodlands, low to mid elevation (east-side
 Cascades, southern Idaho, drier areas of Rocky Mountains, USA), for the
  mid to late twenty-first century. Likelihood and confidence are rated
low, moderate, and high. Low likelihood represents consequences that are
   unlikely (approximately 0 to 33% probability), moderate likelihood
 represents consequences that are about as likely as not (approximately
33 to 66% probability), high likelihood represents consequences that are
    likely to very likely (approximately 66 to 100% probability). Low
   confidence is characterized by low scientific agreement and limited
  evidence, whereas high confidence is characterized by high scientific
 agreement and robust evidence, with moderate confidence falling between
                           those two extremes
-------------------------------------------------------------------------
   Fire-climate       Magnitude of      Likelihood of
   interaction        consequences       consequences       Confidence
------------------------------------------------------------------------
Wildfire           Large increase     High               High
 frequency
Wildfire extent    Large increase     High               High
Wildfire severity  Large increase in  High               High
                    areas with
                    elevated fuel
                    loading
Reburns            Moderate increase  Moderate           Moderate
Stress             Large increase     High               High
 interactions
Regeneration       Low to high        Moderate           Moderate
                    decrease,
                    depending on
                    site
------------------------------------------------------------------------

Risk in high-elevation forests
    Climate-fire risks in high-elevation forests are moderate, with a 
primary factor being increased fire frequency and extent in lower-
elevation forests spreading to higher-elevation systems (Table 3). 
Regeneration could be challenging in locations where seed availability 
is low due to very large fires. High-elevation forests occur in 
mountainous areas across the Northwest. They are characterized by 
species such as subalpine fir (Abies lasiocarpa [Hook.] Nutt.), 
mountain hemlock (Tsuga mertensiana [Bong.] Carriere), and lodgepole 
pine (Pinus contorta var. contorta Engelm. ex S. Watson). High-
elevation forests are characterized by infrequent, stand-replacement 
fire regimes (Agee 1993). Risks of stress interactions are also 
moderate, because drought and insect outbreaks will likely affect high-
elevation forests with increasing frequency.

                                 Table 3
 
      Risk assessment for the effects of fire-climate interactions in
   subalpine coniferous forest and woodland, high elevation (including
 aspen; all U.S. Pacific Northwest mountain ranges), for the mid to late
twenty-first century. Likelihood and confidence are rated low, moderate,
   and high. Low likelihood represents consequences that are unlikely
  (approximately 0 to 33% probability), moderate likelihood represents
  consequences that are about as likely as not (approximately 33 to 66%
probability), high likelihood represents consequences that are likely to
  very likely (approximately 66 to 100% probability). Low confidence is
 characterized by low scientific agreement and limited evidence, whereas
high confidence is characterized by high scientific agreement and robust
  evidence, with moderate confidence falling between those two extremes
-------------------------------------------------------------------------
   Fire-climate       Magnitude of      Likelihood of
   interaction        consequences       consequences       Confidence
------------------------------------------------------------------------
Wildfire           Moderate increase  Moderate           High
 frequency
Wildfire extent    Moderate increase  Moderate           Moderate
Wildfire severity  No change to       Low                Moderate
                    small increase
Reburns            No change to       Low                Moderate
                    small increase
Stress             Small increase     Moderate           Moderate
 interactions
Regeneration       Variable,          Moderate           Moderate
                    depending on
                    fire size
------------------------------------------------------------------------

Historical and contemporary fire-climate relationships
Paleoclimate and fire data
    Wildfire-derived charcoal deposited in lake sediments can be used 
to identify individual fire events and to estimate fire frequency over 
hundreds to thousands of years (Itter, et al., 2017). In combination 
with sediment pollen records, charcoal records help to determine how 
vegetation and fire frequency and severity shifted with climatic 
variability in the past (Gavin, et al., 2007). Existing paleoecological 
reconstructions of the Northwest are based mostly on pollen and 
charcoal records from lakes in forested areas west of the Cascade 
Range, with few studies in the dry interior of the region (Kerns, et 
al., 2017).
    The early Holocene (circa 10 500 to 5,000 years BP) was the warmest 
post-glacial period in the Northwest (Whitlock 1992). During the early 
Holocene, summers were warmer and drier relative to recent historical 
conditions, with more intense droughts (Whitlock 1992; Briles, et al., 
2005). In many parts of the Northwest, these warmer and drier summer 
conditions were associated with higher fire frequency (Whitlock 1992; 
Walsh, et al., 2008; Walsh, et al., 2015).
    Sediment charcoal analysis documented relatively frequent (across 
the paleoecological record) fire activity during the early Holocene in 
eight locations: North Cascade Range (Prichard, et al., 2009), Olympic 
Peninsula (Gavin, et al., 2013), Puget Lowlands (Crausbay, et al., 
2017), southwestern Washington (Walsh, et al., 2008), Oregon Coast 
Range (Long, et al., 1998), Willamette Valley (Walsh, et al., 2010), 
Siskiyou Mountains (Briles, et al., 2005), and Northern Rocky Mountains 
in Idaho (Brunelle and Whitlock 2003) (Table 4). Higher fire frequency 
in these locations was generally associated with higher abundance of 
tree species adapted to survive fire or regenerate soon after fire, 
including Douglas-fir, lodgepole pine, and Oregon white oak (Quercus 
garryana Douglas ex Hook.) (Table 4). Other pollen analyses (without 
parallel charcoal analysis) support the expansion of these species 
during the early Holocene (e.g., Sea and Whitlock 1995; Worona and 
Whitlock 1995), in addition to the expansion of ponderosa pine and oak 
in drier interior forests (Hansen 1943; Whitlock and Bartlein 1997). 
Relatively frequent fire (across the paleoecological record) during the 
early Holocene likely resulted in a mosaic of forest successional 
stages, with species such as red alder (Alnus rubra Bong.) dominating 
early-successional stages in mesic forest types (Cwynar 1987).

                                 Table 4
 
   Dominant tree species (current [late twentieth to early twenty-first
 century] and during the Early Holocene, circa 10 500 to 5,000 yr BP) in
 select locations in the Pacific Northwest, USA, where charcoal analysis
indicated increased fire activity in the warmer and drier summers of the
 Early Holocene. Locations are listed from north to south. These studies
 were selected to cover a range of geographic locations and forest types
 and do not represent a comprehensive list of charcoal analyses for the
   Northwest. For a more comprehensive list, see Walsh, et al. (2015)
 
-------------------------------------------------------------------------
                                                      Early
                                          Current    Holocene
 Region   Elevation       Latitude,       dominant   dominant  Reference
 (site)      (m)         longitude ()       tree       tree
                                         species a  species a
------------------------------------------------------------------------
North           1100    48.658, ^121.04  Douglas-   Lodgepole  Prichard,
 Cascad                                   fir,       pine       et al.,
 e                                        Pacific               2009
 Range,                                   silver
 Washin                                   fir,
 gton                                     western
 (Panth                                   hemlock,
 er                                       western
 Pothol                                   redcedar
 es)
Puget           430   47.772, ^121.811  Douglas-   Douglas-   Crausbay,
 Lowlan                                   fir,       fir        et al.,
 ds,                                      western               2017
 Washin                                   hemlock,
 gton                                     western
 (Marck                                   redcedar
 worth
 State
 Forest
 )
Western          710   47.677, ^124.018  Pacific    Douglas-   Gavin, et
 Olympi                                   silver     fir, red   al.,
 c                                        fir,       alder,     2013
 Penins                                   western    Sitka
 ula,                                     hemlock,   spruce
 Washin                                   western
 gton                                     redcedar
 (Yahoo
 Lake)
Southwe          154   45.805, ^122.494  Douglas-   Oregon     Walsh, et
 stern                                    fir,       white      al.,
 Washin                                   western    oak,       2008
 gton                                     redcedar   Douglas-
 (Battl                                   ,          fir
 e                                        western
 Ground                                   hemlock,
 Lake)                                    grand
                                          fir,
                                          Sitka
                                          spruce
Norther         2250   45.704, ^114.987  Subalpine  Douglas-   Brunelle
 n                                        fir,       fir,       and
 Rocky                                    whitebar   whitebar   Whitlock
 Mounta                                   k pine,    k pine,    2003
 ins,                                     lodgepol   lodgepol
 Idaho                                    e pine,    e pine
 (Burnt                                   Engelman
 Knob                                     n spruce
 Lake)
Willame           69    44.551, ^123.17  Willow,    Oregon     Walsh, et
 tte                                      black      white      al.,
 Valley                                   cottonwo   oak,       2010
 ,                                        od,        Douglas-
 Oregon                                   Oregon     fir,
 (Beave                                   ash,       beaked
 r                                        Oregon     hazel,
 Lake)                                    white      bigleaf
                                          oak        maple,
                                                     red
                                                     alder
Oregon           210   44.167, ^123.584  Western    Douglas-   Long, et
 Coast                                    hemlock,   fir, red   al.,
 Range                                    Douglas-   alder,     1998
 (Littl                                   fir,       Oregon
 e                                        western    white
 Lake)                                    redcedar   oak
                                          , grand
                                          fir,
                                          Sitka
                                          spruce
Siskiyo         1600   42.022, ^123.459  White      Western    Briles,
 u                                        fir,       white      et al.,
 Mounta                                   Douglas-   pine,      2005
 ins,                                     fir        sugar
 Oregon                                              pine,
 (Bolan                                              Oregon
 Lake)                                               white
                                                     oak,
                                                     incense
                                                     cedar
------------------------------------------------------------------------
a Species names that are not otherwise indicated in the text: beaked
  hazel (Corylus cornuta ssp. cornuta Marshall), bigleaf maple (Acer
  macrophyllum Pursh), black cottonwood, (Populus trichocarpa Torr. & A.
  Gray ex Hook.), incense-cedar (Calocedrus decurrens [Torr.] Florin),
  Oregon ash (Fraxinus latifolia Benth.), Pacific silver fir (Abies
  amabilis Douglas ex J. Forbes), sugar pine (Pinus lambertiana
  Douglas), western redcedar (Thuja plicata Donn ex D. Don), western
  white pine (Pinus monticola Douglas ex D. Don.), willow (Salix spp.
  L.)

    Paleoecological studies (covering the early Holocene and other time 
periods) indicate that climate has been a major control on fire in the 
Northwest over millennia, with interactions between fire and 
vegetation. During times of high climatic variability and fire 
frequency (e.g., the early Holocene), fires were catalysts for large-
scale shifts in forest composition and structure (Prichard, et al., 
2009; Crausbay, et al., 2017). Species that persisted during these 
times of rapid change have life history traits that facilitate survival 
in frequently disturbed environments (Brubaker 1988; Whitlock 1992), 
including red alder, Douglas-fir, lodgepole pine, ponderosa pine, and 
Oregon white oak, which suggests that these species may be successful 
in a warmer future climate (Whitlock 1992; Prichard, et al., 2009).
Fire-scar and tree-ring records
    Fire-scar studies indicate that climate was historically a primary 
determinant of fire frequency and extent in the Northwest. Years with 
increased fire frequency and area burned were generally associated with 
warmer and drier spring and summer conditions in the Northwest (Hessl, 
et al., 2004; Wright and Agee 2004; Heyerdahl, et al., 2008; Taylor, et 
al., 2008). Climate of previous years does not have a demonstrated 
effect on fire, unlike other regions such as the Southwest, most likely 
because fuels are not as limiting for fire across the Northwest 
(Heyerdahl, et al., 2002; Hessl, et al., 2004).
    Warmer and drier conditions in winter and spring are more common 
during the El Nino phase of the El Nino-Southern Oscillation (ENSO) in 
the Northwest (Mote, et al., 2014). The Pacific Decadal Oscillation 
(PDO) is an ENSO-like pattern in the North Pacific, resulting in sea 
surface temperature patterns that appeared to occur in 20 to 30 year 
phases during the twentieth century (Mantua, et al., 1997). Positive 
phases of the PDO are associated with warmer and drier winter 
conditions in the Northwest.
    Associations between large fire years and El Nino have been found 
in the interior Northwest (e.g., Heyerdahl, et al., 2002), as have 
associations between large fire years and the (warm, dry) positive 
phase of the PDO (Hessl, et al., 2004). Other studies have found 
ambiguous or non-significant relationships between fire and these 
climate cycles in the Northwest (e.g., Hessl, et al., 2004; Taylor, et 
al., 2008). However, interactions between ENSO and PDO (El Nino plus 
positive phase PDO) were associated with increased area burned 
(Westerling and Swetnam 2003) and synchronized fire in some years in 
dry forests across the inland Northwest (Heyerdahl, et al., 2008).
    The PDO and ENSO likely affect fire extent by influencing the 
length of the fire season (Heyerdahl, et al., 2002). Warmer and drier 
winter and spring conditions increase the length of time that fuels are 
flammable (Wright and Agee 2004). Although climate change effects on 
the PDO and ENSO are uncertain, both modes of climatic variation 
influence winter and spring conditions in the Northwest, whereas summer 
drought during the year of a fire has the strongest association with 
major fire years at the site and regional scales (Hessl, et al., 2004). 
Summer drought conditions are likely more important than in other 
regions where spring conditions are more strongly related to fire, 
because the Northwest has a winter-dominant precipitation regime; fire 
season occurs primarily in late summer (August through September), and 
summer drought reduces fuel moisture (Hessl, et al., 2004; Littell, et 
al., 2016).
Contemporary climate and fire records
    In the twentieth century, wildfire area burned in the Northwest was 
positively related to low precipitation, drought, and temperature 
(Littell, et al., 2009; Abatzoglou and Kolden 2013; Holden, et al., 
2018). Warmer spring and summer temperatures across the western United 
States cause early snowmelt, increased evapotranspiration, lower summer 
soil and fuel moisture, and thus longer fire seasons (Westerling 2016). 
Precipitation during the fire season also exerts a strong control on 
area burned through wetting effects and feedbacks to vapor pressure 
deficit (a measure of humidity; Holden, et al., 2018). Between 2000 and 
2015, warmer temperatures and vapor pressure deficit decreased fuel 
moisture during the fire season in 75% of the forested area in the 
western U.S. and added about 9 days per year of high fire potential 
(defined using several measures of fuel aridity; Abatzoglou and 
Williams 2016).
    Periods of high annual area burned in the Northwest are also 
associated with high (upper atmosphere) blocking ridges over western 
North America and the North Pacific Ocean. Blocking ridges occur when 
centers of high pressure occur over a region in such a way that they 
prevent other weather systems from moving through. These blocking 
ridges, typical in the positive phase of the PDO (Trouet, et al., 
2006), divert moisture away from the region, increasing temperature and 
reducing relative humidity (Gedalof, et al., 2005). Prolonged blocking 
and more severe drought (Brewer, et al., 2012) are needed to dry out 
fuels in mesic to wet forest types (e.g., Sitka spruce [Picea 
sitchensis (Bong.) Carriere], western hemlock) along coastal Oregon and 
Washington. With increased concentrations of carbon dioxide in the 
atmosphere, the persistence of high blocking ridges that divert 
moisture from the region may increase (Lupo, et al., 1997, as cited in 
Flannigan, et al., 2009), further enhancing drought conditions and the 
potential for fire.
    Lightning ignitions also affect wildfire frequency. However, 
research on lightning with recent and future climate change is 
equivocal. Some studies suggest that lightning will increase up to 40% 
globally in a warmer climate (Price and Rind 1994; Reeve and Toumi 
1999; Romps, et al., 2014), although a recent study suggests that 
lightning may decrease by as much as 15% globally (Finney, et al., 
2018).
    Increases in annual area burned are generally associated with 
increases in area burned at high severity. Fire size, fire severity, 
and high-severity burn patch size were positively correlated in 125 
fires in the North Cascades of Washington over a recent 25 year period 
(Cansler and McKenzie 2014). Other analyses have similarly shown a 
positive correlation between annual area burned and area burned 
severely (in large patches) in the Northwest (Dillon, et al., 2011; 
Abatzoglou, et al., 2017; Reilly, et al., 2017). The annual extent of 
fire has increased slightly in the Northwest, although the proportion 
of area burning at high severity did not increase over the 1985 to 2010 
period, either for the region as a whole or for any subregion (Reilly, 
et al., 2017). Similarly, an analysis of recent fires (1984 to 2014) in 
the Northwest found no decrease in the proportion of unburned area 
within fire perimeters (Meddens, et al., 2018).
    Many studies have found that bottom-up controls such as vegetation, 
fuels, and topography are more important drivers of fire severity than 
climate in Western forests (e.g., Dillon, et al., 2011; Parks, et al., 
2014). The direct influence of climate on fire severity is 
intrinsically much stronger in moister and higher-elevation forests, 
because drying of fuels in these systems requires extended warm and dry 
periods. Fire severity in many dry forest types is influenced primarily 
by fuel quantity and structure (Parks, et al., 2014). However, fuel 
accumulations associated with fire exclusion in dry forests may be 
strengthening the influence of climate on fire severity, likely 
resulting in increased fire severity in drier forest types (Parks, et 
al., 2016a).
Wildfire projections under changing climate
    Historical patterns suggest that higher temperatures, stable or 
decreasing summer precipitation, and increased drought severity in the 
Northwest will likely increase the frequency and extent of fire. Models 
can help to explore potential future fire frequency and severity in a 
changing climate, with several types of models being used to project 
future fire (McKenzie, et al., 2004). We focused here on models for 
which output is available in the Northwest-empirical (statistical) 
models and mechanistic (process-based) models. Both types of models 
have limitations as well as strengths, but they are conceptually useful 
to assess potential changes in fire with climate change.
Fire projections by empirical models
    Empirical models use the statistical relationship between observed 
climate and area burned during the historical record (the past 100 
years or so) to project future area burned. Future area burned is based 
on projections of future temperature and precipitation, usually from 
global climate models. These models do not account for the potential 
decreases in burn probability in areas that have recently burned, or 
for long-term changes in vegetation (and thus flammability) with 
climate change (Parks, et al., 2015; McKenzie and Littell 2017; 
Littell, et al., 2018). They also do not account for human influence on 
fire ignitions (Syphard, et al., 2017).
    Numerous studies have developed empirical models to project future 
area burned or fire potential at both global (Krawchuk, et al., 2009; 
Moritz, et al., 2012) and regional scales (e.g., western U.S.; 
McKenzie, et al., 2004; Littell, et al., 2010; Yue, et al., 2013; 
Kitzberger, et al., 2017). All studies suggest that fire potential, 
area burned, or both will increase in the western U.S. in the future 
with warming climate. Below we highlight a few examples that explicitly 
address the Northwest. These examples provide future fire projections 
at relatively coarse spatial scales, with changes in area burned being 
variable across landscapes.
    McKenzie, et al., (2004) projected that, with a mean temperature 
increase of 2 C, area burned by wildfire will increase by a factor of 
1.4 to 5 for most Western states, including Idaho, Montana, Oregon, and 
Washington. Kitzberger, et al., (2017) projected increases in annual 
area burned of five times the median in 2010 to 2039 compared to 1961 
to 2004 for the 11 conterminous Western states. Models developed by 
Littell, et al., (2010) for Idaho, Montana, Oregon, and Washington 
suggested that area burned will double or triple by the 2080s, based on 
future climate projections for two global climate models (Fig. 4). 
Median area burned was projected to increase from about 0.2 million ha 
historically to 0.3 million ha in the 2020s, 0.5 million ha in the 
2040s, and 0.8 million ha in the 2080s. The projections cited here are 
coarse scale, and area burned can be expected to vary from place to 
place within the area of the projections.
Fig. 4
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

          Conceptual model showing that indirect effects of climate 
        change via disturbance cause faster shifts in vegetation than 
        do direct effects of climate change. Adapted from McKenzie, et 
        al. (2004 (https://fireecology.springeropen.com/articles/
        10.1186/s42408-019-0062-8#ref-CR129)).

    Littell, et al., (2010) also developed empirical models at a finer 
(ecosection) scale for the state of Washington. The relatively low 
frequency of fire in coastal forests makes development of empirical 
models difficult, so the output from these models for coastal forests 
is uncertain. For drier forest types, potential evapotranspiration and 
water balance deficit were the most important variables explaining area 
burned. In forested ecosystems (Western and Eastern Cascades, Okanogan 
Highlands, and Blue Mountains ecosections), the mean area burned was 
projected to increase by a factor of 3.8 in the 2040s compared to 1980 
to 2006. An updated version of these models, expanded to the western 
U.S. (Littell, et al., 2018), also suggests that area burned will 
increase in the future for most forested ecosections of the Northwest, 
but increases in area burned may be tempered, or area burned may 
decrease, in areas that are more fuel limited (e.g., in non-forest 
vegetation types).
    Another application of empirical models is to project the future 
incidence of very large fires, often defined as the largest 5 to 10% of 
fires or fires >5,000 ha. Barbero, et al., (2015) projected that the 
annual probability of very large fires will increase by a factor of 
four in 2041 to 2070 compared to 1971 to 2000. Projections by Davis, et 
al., (2017) suggested that the proportion of forests highly suitable 
for fires >40 ha will increase by >20% in the next century for most of 
Oregon and Washington, but less so for the Coast Range and Puget 
Lowlands. The largest projected increases were in the Blue Mountains, 
Klamath Mountains, and East Cascades. The number of fires that escape 
initial attack will also likely increase (Fried, et al., 2008).
    Few empirical model projections are available for future fire 
severity. Using empirical models, Parks, et al., (2016a) suggested that 
fire severity in a warming climate may not change significantly in the 
Northwest, because fuels limit fire severity. However, altered fire 
severity will depend partly on vegetation composition and structure (as 
they affect fuels), and climate change is expected to alter vegetation 
composition and structure both directly and indirectly (through 
disturbance). Empirical models do not account for these potential 
changes in vegetation and fuels (among other limitations; see McKenzie 
and Littell 2017). In the near term, high stem density as a result of 
fire exclusion and past management may increase fire severity in dry, 
historically frequent-fire forests (Haugo, et al., 2019).
Fire projections by mechanistic models
    Mechanistic models allow for exploration of potential interactions 
between vegetation and fire under changing and potentially novel 
climate. Mechanistic models can also account for elevated carbon 
dioxide concentration on vegetation, which could result in increased 
vegetation productivity (and fuel loading). Examples of mechanistic 
models that simulate fire include dynamic global vegetation models, 
such as MC1 (Bachelet, et al., 2001), LANDIS-II (Scheller and Mladenoff 
2008), and Fire-BioGeoChemical (Fire-BGC; Keane, et al., 1996).
    Using the MC1 dynamic global vegetation model for the western \3/4\ 
of Oregon and Washington, Rogers, et al., (2011) projected a 76 to 310% 
increase in annual area burned and a 29 to 41% increase in burn 
severity (measured as aboveground carbon consumed by fire) by the end 
of the twenty-first century, with the degree of increase depending on 
climate scenario. These projected changes were largely driven by 
increased summer drought. Under a hot and dry climate scenario (with 
more frequent droughts), large fires were projected to occur throughout 
the twenty-first century (including the early part), primarily in mesic 
forests west of the Cascade crest.
    Using the MC2 model (an updated version of MC1), Sheehan, et al., 
(2015) also projected increasing fire activity in Idaho, Oregon, 
Washington, and western Montana. Mean fire return interval was 
projected to decrease across all forest-dominated subregions, with or 
without fire suppression. Projected decreases in mean fire interval 
were as high as 82% in the interior subregions without fire 
suppression; projected decreases in mean fire interval for the 
westernmost subregion were as high as 48% without fire suppression.
    The MC1 and MC2 models have also been calibrated and run for 
smaller subregions in the Northwest. For the Willamette Valley, Turner, 
et al., (2015) projected (under a high temperature increase scenario) 
increased fire frequency, with average area burned per year increasing 
by a factor of nine relative to the recent historical period (1986 to 
2010); area burned over the recent historical period was very low (0.2% 
of the area per year). For a western Washington study region, MC2 
projected a 400% increase in annual area burned in the twenty-first 
century compared to 1980 to 2010 (Halofsky, et al., 2018a). Although 
the projected average annual area burned was still only 1.2% of the 
landscape, some fire years were very large, burning 10 to 25% of the 
study region.
    The MC1 model projected increased fire frequency and extent in 
forested lands east of the Cascade crest (Halofsky, et al., 2013; 
Halofsky, et al., 2014). Fire was projected to burn more than 75% of 
forested lands several times between 2070 and 2100. On average, 
projected future fires burned the most forest under a hot, dry 
scenario. Applying the MC2 model to a larger south-central Oregon 
region, Case, et al., (2019) suggested that future fire will become 
more frequent in most vegetation types, increasing most in dry and 
mesic forest types. For forested vegetation types, fire severity was 
projected to remain similar or increase slightly compared to historical 
fire severity.
    The LANDIS-II model has been applied to the Oregon Coast Range in 
the Northwest. Creutzburg, et al., (2017) found that area burned over 
the twenty-first century did not increase significantly with climate 
change compared to historical levels, but fire severity and extreme 
fire weather did increase.
    Fire-BGC models have mostly been applied in the northern U.S. Rocky 
Mountains, which overlaps with the Northwest. For northwestern Montana 
(Glacier National Park), Keane, et al., (1999) used Fire-BGC in a 
warmer, wetter climate scenario to project higher vegetation 
productivity and fuel accumulations that contribute to more intense 
crown fires and larger fire sizes. Fire frequency also increased over a 
250 year simulation period: fire rotation decreased from 276 to 213 
years, and reburns occurred in 37% of the study area (compared to 17% 
under historical conditions). In drier locations (low-elevation south-
facing sites), low-severity surface fires were more common, with fire 
return intervals of 50 years.
    Mechanistic modeling suggests that fire frequency and area burned 
will increase in the Northwest. Fire severity may also increase, 
depending partly on forest composition, structure, and productivity 
over time. Warmer temperatures in winter and spring, and increased 
precipitation during the growing season (even early in the growing 
season), could increase forest productivity. This increase in 
productivity would maintain or increase fuel loadings and promote high-
severity fires when drought and ignitions occur. In mechanistic model 
projections for the region, some of the largest increases in fire 
severity (Keane, et al., 1999; Case, et al., 2019) and the largest 
single fire years (Halofsky, et al., 2013; Halofsky, et al., 2018a) 
occurred in wetter scenarios with increased forest productivity. Future 
increased fire frequency without increased vegetation productivity is 
likely to result in decreased fire severity because of reduction in 
fuels as well as the potential for type conversion to vegetation 
characterized by less woody biomass. However, in highly productive 
systems such as forests west of the Cascade crest, future fires will 
probably be high severity (as they were historically) and more frequent 
(Rogers, et al., 2011; Halofsky, et al., 2018a).
Short-interval reburns
    A reburn occurs when the perimeter of a recent past fire is 
breached by a subsequent fire, something that all fire-prone forests 
have experienced. In the Northwest, reburns in the early twentieth 
century were documented in some of the earliest forestry publications 
(e.g., Isaac and Meagher 1936). However, under a warming climate, 
increased frequency and extent of fire will increase the likelihood of 
reburns, increasing the need to understand how earlier fires affect 
subsequent overlapping fires and how forests respond to multiple fires. 
Recent concern about reburns centers on projections that short-
interval, high-severity (i.e., stand-replacing) reburns may become more 
common (Westerling, et al., 2011; Prichard, et al., 2017). Multiple 
fires can interact as linked disturbances (Simard, et al., 2011), 
whereby the first fire affects the likelihood of occurrence, size, or 
magnitude (intensity, severity) of a reburn. Multiple fires can also 
interact to produce compound disturbance effects (Paine, et al., 1998), 
in which ecological response after a reburn is qualitatively different 
than after the first fire.
Effects of past fire on future fire occurrence
    Interactions between past forest fires and the occurrence of 
subsequent fires are generally characterized by negative feedbacks: 
fires are less likely to start within or spread into recently burned 
areas (i.e., within the last 5 to 25 years) compared to similar areas 
that have not experienced recent fire. For example, lightning-strike 
fires within the boundary of recently burned areas in the U.S. Rocky 
Mountains (Idaho, Montana) were less likely to grow to fires larger 
than 20 ha than were lightning-strike fires in comparable areas outside 
recent fire boundaries (Parks, et al., 2016b). This negative relation 
between past fires and likelihood of future fires is generally 
attributed to limits on ignition potential and initial spread of fires 
through fine woody fuels, which are sparse following fire. Fine fuels 
are consumed by the first fire and do not recover to sufficient levels 
until at least a decade later in many interior forest systems in the 
Northwest (Isaac 1940; Donato, et al., 2013) and U.S. Rocky Mountains 
(Nelson, et al., 2016, 2017). However, negative feedbacks can be short-
lived (or non-existent) in productive west-side forests in the 
Northwest, where fuels are abundant in early-successional forests 
(Isaac 1940; Agee and Huff 1987; Gray and Franklin 1997).
    Past fires in the northern U.S. Rocky Mountains have also been 
effective at preventing the spread of subsequent fires into their 
perimeters (Teske, et al., 2012; Parks, et al., 2015). Similar results 
have been found in mixed-conifer forests of the interior Northwest, 
where past wildfire perimeters inhibited the spread of the 2007 Tripod 
Complex Fire in eastern Washington (Prichard and Kennedy 2014). This 
limitation of fire spread decreases with time. The probability that 
reburns will be inhibited by earlier fires is near 100% in the first 
year post fire, but is only 30% by 15 to 20 years post fire (Parks, et 
al., 2015). However, extreme fire weather can dampen buffering effects 
of reburns at any interval between fires, such that past fire 
perimeters become less effective at inhibiting reburns during warm, 
dry, and windy conditions (Parks, et al., 2015).
Effects of past fire on future fire severity
    Fire severity (fire-caused vegetation mortality) in a reburn is 
affected by interactions among severity of the first fire, climate 
setting and forest type, interval between fires, and weather at the 
time of the reburn. Reburns are typically less severe when the interval 
between fires is shorter than 10 to 15 years (Parks, et al., 2014; 
Harvey, et al., 2016b; Stevens-Rumann, et al., 2016). After 10 to 15 
years, the effects of past fires on reburn severity diverge in 
different ecological contexts.
    In areas where tree and shrub regeneration is prolific following 
one severe fire (e.g., moist Douglas-fir forests, subalpine forests 
dominated by lodgepole pine, some mixed-conifer forests [e.g., 
southwest Oregon mixed conifer forests with a hardwood component]), 
fire severity can be greater in reburns than in comparable single burns 
once the interval between fires exceeds 10 to 12 years (Thompson, et 
al., 2007; Harvey, et al., 2016b). In lower-elevation, drier, and more 
fuel-limited forests (e.g., ponderosa pine forests and woodlands, areas 
with slower woody plant establishment following fire), past fire limits 
future fire severity, often for 20 to 30 years (Parks, et al., 2015; 
Harvey, et al., 2016b; Stevens-Rumann, et al., 2016). In these lower-
productivity forests, the severity of past fire has been found to be 
the best predictor of reburn severity (Parks, et al., 2014; Harvey, et 
al., 2016b), but this is not necessarily the case in higher-
productivity forests (Thompson, et al., 2007; Stevens-Rumann, et al., 
2016). Surface fuel treatment followed by tree planting can greatly 
reduce the intensity of a reburn and allow most newly established trees 
to survive (Lyons-Tinsley and Peterson 2012).
    Of particular concern for forest resilience is how and why forests 
may experience two severe fires in short succession. In the northern 
U.S. Rocky Mountains, the likelihood of experiencing two successive 
stand-replacing fires (i.e., a severe fire followed by a severe reburn) 
is greatest (1) in areas with high post-fire regeneration capacity 
(e.g., higher-elevation subalpine forests on moist sites), and (2) when 
the reburn occurs during warm, dry conditions (Harvey, et al., 2016b). 
In high-productivity west-side forests of Oregon and Washington, the 
potential for two successive high-severity burns may always exist 
(e.g., Isaac 1940), but occurrence depends on ignition and low fuel 
moisture.
Effects of reburns on forest species composition and structure
    Short-interval reburns can produce compound effects on tree 
regeneration, altering species composition in some cases and shifting 
to non-forest vegetation in others. For example, thin-barked species, 
which do not survive fire but instead regenerate from seed following 
fire-induced mortality (e.g., lodgepole pine), can face ``immaturity 
risk'' if the interval between one fire and a reburn is too short to 
produce a sufficient canopy seedbank (Keeley, et al., 1999; Turner, et 
al., 2019). In northern U.S. Rocky Mountain systems, low- and moderate-
severity reburns have shifted dominance from lodgepole pine toward 
thick-barked species that can resist fire, such as ponderosa pine 
(Larson, et al., 2013; Stevens-Rumann and Morgan 2016).
    In the western Cascades of southern Washington, areas that burned 
in the 1902 Yacolt Burn and subsequently reburned within 30 years were 
characterized by much lower conifer regeneration than areas that burned 
only once (Gray and Franklin 1997). However, in the Klamath and 
Siskiyou mountains of southwestern Oregon, a short-interval (15 years 
between fires), high-severity reburn had no compound effect on 
regeneration (2 years post fire) of Douglas-fir, the dominant tree 
species (Donato, et al., 2009b), with no difference from areas that 
burned once at a longer interval (>100 years between fires). Plant 
species diversity and avian diversity were higher in reburns compared 
to once-burned areas, with hardwoods contributing to habitat diversity 
in the reburn areas (Donato, et al., 2009b; Fontaine, et al., 2009).
    The effects of reburns on post-fire conifer regeneration seem to 
depend on legacy trees that survive both fires, providing seed across 
fire events (Donato, et al., 2009b). In systems where legacy trees are 
rare (i.e., thin-barked species easily killed by fire) or where shrubs 
and hardwoods can outcompete trees for long durations, reburns are more 
likely to produce lasting compound effects on forest structure and 
composition, possibly resulting in a shift to non-forest vegetation.
Disturbance and stress interactions
    Combinations of biotic and abiotic stressors, or stress complexes, 
will likely be major drivers of shifts in forest ecosystems with 
changing climate (Manion 1991). A warmer climate will affect forests 
directly through soil moisture stress and indirectly through increased 
extent and severity of disturbances, particularly fire and insect 
outbreaks (McKenzie, et al., 2009).
Water deficit and disturbance interactions
    Although water deficit (the condition in which potential summer 
atmospheric and plant demands exceed available soil moisture) is rarely 
fatal by itself, it is a predisposing factor that can exacerbate the 
forest stress complex (Manion 1991; McKenzie, et al., 2009). Water 
deficit directly contributes to potentially lethal stresses in forest 
ecosystems by intensifying negative water balances (Stephenson 1998; 
Milne, et al., 2002; Littell, et al., 2008; Restaino, et al., 2016). 
Water deficit also indirectly increases the frequency, extent, and 
severity of disturbances, especially wildfire and insect outbreaks 
(McKenzie, et al., 2004; Logan and Powell 2009). These indirect 
disturbances alter forest ecosystem structure and function, at least 
temporarily, much faster than do chronic effects of water deficit 
(e.g., Loehman, et al., 2017; Fig. 4).
Interactions among drought, insect outbreaks, and fire
    During the past few decades, wildfires and insect outbreaks have 
affected a large area across the Northwest (Fig. 5). Increased area 
burned has been at least partly caused by extreme drought-wildfire 
dynamics, which will likely become more prominent as drought severity 
and area burned increase in the future (Parks, et al., 2014; McKenzie 
and Littell 2017). Insect disturbance has likewise expanded across the 
Northwest since 1990, catalyzed by higher temperature and the 
prevalence of dense, low-vigor forests. Cambium feeders, such as bark 
beetles, are associated with prolonged droughts, in which tree defenses 
are compromised (Logan and Bentz 1999; Carroll, et al., 2004; Hicke, et 
al., 2006). Patches of fire-insect disturbance mosaic are starting to 
run into each other (Fig. 5), and similar to reburns, are an inevitable 
consequence of increasing disturbance activity, even in the absence of 
mechanistic links among disturbances.
Fig. 5
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

          Recent disturbances in the Northwest, USA, showing wildfire 
        extent for 1984 to 2017 (orange), and insect and disease extent 
        for 1997 to 2017 (brown). Data sources: Monitoring Trends in 
        Burn Severity (https://www.mtbs.gov) and U.S. Forest Service 
        Insect and Disease Detection Survey (https://www.fs.fed.us/
        foresthealth/applied-sciences/mapping-reporting/gis-spatial-
        analysis/detection-surveys.shtml). Map credit: Robert Norheim.

    In a review of the fire-bark beetle literature, Hicke, et al. 
(2012) noted that, despite varying research approaches and questions, 
much agreement existed on fire hazard (defined as changes to fuels and 
potential fire behavior) after bark beetle outbreaks. There was strong 
agreement that surface fire and torching potential increased during the 
gray phase (e.g., 5 to 10 years following outbreaks, when snags remain 
standing; but see Woolley, et al., 2019), but that crown fire potential 
was reduced in this phase. Similarly, there was agreement that fire 
hazard was lower in the old phase (i.e., silver phase), which occurs 1 
to several decades after outbreak, when beetle-killed snags have 
fallen, understory vegetation increases, and seedlings establish. 
However, there was disagreement regarding fire potential during the red 
phase (0 to 4 years after outbreak initiation), when trees retain their 
drying needles and changes in foliar chemistry can increase 
flammability. Many studies have concluded that during this 
approximately 1 to 4 year period, fire hazard increases (Klutsch, et 
al., 2011 [but see Simard, et al., 2011], Hoffman, et al., 2012, Jolly, 
et al., 2012; Jenkins, et al., 2014). Fire hazard has been found to 
increase as the proportion of the stand killed by bark beetles 
increases, regardless of forest type (Page and Jenkins 2007; DeRose and 
Long 2009; Hoffman, et al., 2012).
    Concern has also risen as to whether fire occurrence and severity 
will increase following outbreaks of bark beetles (e.g., Hoffman, et 
al., 2013), although empirical support for such interactions has been 
lacking (Parker, et al., 2006; Hicke, et al., 2012). Insect outbreaks 
have not been shown to increase the likelihood of fire or area burned 
(Kulakowski and Jarvis 2011; Flower, et al., 2014; Hart, et al., 2015; 
Meigs, et al., 2015). Further, when fire occurs in post-outbreak 
forests, most measures of fire severity related to fire-caused 
vegetation mortality are generally similar between beetle-affected 
forests and areas that were unaffected by pre-fire outbreaks. Field 
studies in Oregon showed that burn severity (fire-caused vegetation 
mortality) was actually lower in lodgepole pine forests affected by 
mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins) than 
analogous unaffected forests that burned (Agne, et al., 2016). In an 
analysis of recent (1987 to 2011) fires across the Northwest, Meigs, et 
al., (2016) also found that burn severity (from satellite-derived burn 
severity indices) was lower in forests with higher pre-fire insect 
outbreak severity.
    Field studies in California, the Rocky Mountains, and interior 
British Columbia, Canada, conducted in a range of forest types have 
also explored the relationship between beetle outbreak severity (pre-
fire basal area killed by beetles) and burn severity (fire-caused 
vegetation mortality), and suggest relatively minor effects of beetle 
outbreaks on burn severity. When fire burned through red stages (1 to 4 
years post outbreak, when trees retain red needles) in dry conifer 
forests of California, small increases (e.g., 8 to 10% increase in 
fire-caused tree mortality) in burn severity were observed in areas of 
high outbreak severity (Stephens, et al., 2018). In dry Douglas-fir 
forests in Wyoming, fire severity in the gray phase (4 to 10 years post 
outbreak) of Douglas-fir beetle (Dendroctonus pseudotsugae Hopkins) 
outbreak was unaffected by beetle outbreak severity (Harvey, et al., 
2013). Similar results of minimal beetle effect on fire severity were 
reported in gray-stage spruce-fir forests in Colorado, USA (Andrus, et 
al., 2016). In lodgepole pine-dominated forests affected by MPB, 
outbreak effects on burn severity differed by weather and stage of 
outbreak. For example, in both green and red phases (when most beetle-
killed trees retained crowns fading from green to red), fire severity 
increased with pre-fire beetle outbreak severity under moderate but not 
extreme (e.g., hot, dry, windy) weather (Harvey, et al., 2014a). 
Conversely, in the red and gray stages, fire severity increased with 
pre-fire outbreak severity under extreme but not moderate weather 
(Harvey, et al., 2014b).
    In British Columbia, gray-stage post-outbreak stands did not burn 
more severely than unaffected stands for most measures of burn severity 
(Talucci, et al., 2019). The effects of beetle outbreaks on fire 
severity in forest types typified by stand-replacing fire regimes seem 
to be overall variable and minor, especially given that such forest 
types are inherently characterized by severe fire. The key exception to 
the otherwise modest effects of pre-fire beetle outbreaks on burn 
severity is the effect of deep wood charring and combustion on beetle-
killed snags that burn. This effect has been reported across stages and 
forest type when measured, and consistently increases with pre-fire 
beetle outbreak severity (Harvey, et al., 2014b; Talucci, et al., 
2019). Because fire intensity and thus severity are driven by 
topography, weather, and fuels, beetle-outbreak-induced changes to fuel 
structures may play a minor role in affecting fire severity. In all 
cases in studies above where topography and weather were quantified, 
fire severity responded strongly and consistently to these factors 
irrespective of pre-fire beetle outbreaks.
    In the Northwest, lodgepole pine forests have been affected by MPB 
outbreaks, with high mortality in some locations (e.g., Okanogan-
Wenatchee Forest; Fig. 6). Widely distributed at mid to higher 
elevations in the Rocky Mountains, lodgepole pine is the dominant 
species over much of its range there, forming nearly monospecific 
stands. In the Northwest, lodgepole pine occurs at mid to higher 
elevations in the Cascade Range and eastward, and monospecific stands 
are limited to early seral stages and specific soil conditions (e.g., 
Pumice Plateau in central Oregon). In some populations in the 
Northwest, lodgepole pine forests have also adapted to stand-replacing 
fires via cone serotiny.
Fig. 6
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

          Number of trees killed by beetles in Okanogan-Wenatchee 
        National Forest, Washington, USA, from 1980 to 2016. Data 
        source: C. Mehmel, Okanogan-Wenatchee National Forest, 
        Washington, USA.

    Bark beetle outbreaks and subsequent fire may interact to affect 
post-fire forest recovery, but results differ depending on the dominant 
regeneration mechanism of the tree attacked by beetles. Species with a 
persistent canopy seedbank, such as lodgepole pine, are minimally 
affected by compound disturbances between beetle outbreaks and fire. 
For example, in the Cascade Range and Rocky Mountains, areas that 
experienced beetle outbreaks prior to fire had similar levels of post-
fire lodgepole pine seedling establishment compared to areas that had 
fire only (Harvey, et al., 2014a; Harvey, et al., 2014b; Edwards, et 
al., 2015; Agne, et al., 2016). Species such as Douglas-fir, which do 
not have a persistent canopy seedbank, have been shown to have lower 
post-fire seedling establishment in areas affected by Douglas-fir 
beetle outbreaks and fire (Harvey, et al., 2013), although effects may 
be transient and disappear with time since fire (Stevens-Rumann, et 
al., 2015).
Interactions among fungal pathogens and other stressors
    The effects of weather and climate on fungal pathogens vary by 
species, with the spread of some pathogens facilitated by drought and 
others by wet periods (Klopfenstein, et al., 2009; Sturrock, et al., 
2011; Ayres, et al., 2014). Forests with low vigor and physiologically 
stressed trees (e.g., dense stands) are generally more susceptible to 
fungal pathogens. In the Northwest, a wide range of root rots and other 
native fungal pathogens exists in all forest types. For example, on the 
west side of the Cascade Range, laminated root rot (Phellinus weirii 
[Murrill] Gilb.) is widespread, causing small pockets of mortality in 
Douglas-fir (Agne, et al., 2018). However, no evidence exists that this 
pathogen has been or will be accelerated by a warmer climate. Other 
pathogens, such as Swiss needle cast (Phaeocryptopus gaeumannii [T. 
Rohde] Petrak), may be favored by warmer and wetter winters (Agne, et 
al., 2018). Fungal pathogens stress trees and may increase 
susceptibility to insect infestations. For example, Douglas-fir beetle 
is closely associated with laminated root rot centers in forests on the 
west side of the Cascades in Oregon and Washington (Goheen and Hansen 
1993). Overall, interactions between fungal pathogens and fire with 
climate change are uncertain.
Stress complexes and forest mortality
    Recent large-scale tree mortality events in the Southwest 
(Breshears, et al., 2005), Texas (Schwantes, et al., 2016), and 
California, USA (Young, et al., 2017), have been caused by multi-year 
droughts weakening trees, followed by various beetle species acting as 
the mortality agents. It is likely that more intense and longer 
droughts will increase in the future under changing climate (Trenberth, 
et al., 2014), and interactions between drought and other disturbance 
agents are likely to cause tree mortality. As noted above, fungal 
pathogens may contribute to increasing insect outbreaks (Goheen and 
Hansen 1993), along with increasing temperatures, shorter winters, and 
tree stress. Fire-caused tree mortality will also likely be affected by 
interacting disturbances. In some cases, fire severity has been 
marginally higher in areas affected by beetle mortality (Harvey, et 
al., 2014a; Harvey, et al., 2014b; Stephens, et al., 2018). However, 
empirical studies examining the effects of large-scale tree mortality 
events on fire behavior are limited (Stephens, et al., 2018). Modeling 
studies suggest that fire rate of spread may increase after mortality 
events (e.g., Perrakis, et al., 2014).
Effects of changing disturbance regimes on forest structure and 
        composition
    In Northwest forest ecosystems, warming climate and changing 
disturbance regimes are likely to lead to changes in species 
composition and structure, probably over many decades. In general, 
increased fire frequency will favor plant species with life history 
traits that allow for survival with more frequent fire (Chmura, et al., 
2011). These include (1) species that can resist fires (e.g., thick-
barked species such as Douglas-fir, western larch [Larix laricina 
Nutt.], and ponderosa pine); (2) species with high dispersal ability 
that can establish after fires (e.g., Douglas-fir); and (3) species 
with serotinous cones that allow seed dispersal from the canopy after 
fire (e.g., lodgepole pine) (Rowe 1983; Agee 1993).
    In the forest understory, increased fire frequency and extent will 
likely create more opportunities for establishment by invasive species 
(Hellmann, et al., 2008). Species that can endure fires (sprouters) and 
seedbank species (evaders) are also likely to increase with more 
frequent fire. For example, sprouting shrubs and hardwoods are prolific 
after fire in southwest Oregon (Halofsky, et al., 2011). However, high-
intensity fire can consume or kill seeds stored in the upper soil 
layers and kill shallow belowground plant parts, and repeated fires at 
short intervals can deplete seed stores and belowground plant resources 
(Zedler, et al., 1983).
    More frequent fire will likely decrease abundance of avoider 
species, including shade-tolerant species, species with thin bark, and 
slow invaders after fire (Chmura, et al., 2011). Forest stands composed 
primarily of fire-susceptible evader species, such as western hemlock, 
subalpine fir, and Engelmann spruce (Picea engelmannii Parry ex 
Engelm.), will likely have higher mortality for a given fire intensity 
than stands composed of more fire-resistant species, such as mature 
Douglas-fir and western larch. If fire-sensitive species are not able 
to re-seed into burned areas and re-establish themselves (because of 
short fire intervals, competition, or harsh conditions for seedling 
establishment), these species can be lost from a site (Stevens-Rumann 
and Morgan 2016). Direct mortality or lack of regeneration of fire-
sensitive species with more frequent fire will favor more fire-adapted 
species that can survive fire or regenerate after fire. For example, in 
southwest Oregon, shrubs and hardwoods are likely to increase in 
abundance with increased fire frequency and reduced conifer 
regeneration in some locations (Tepley, et al., 2017).
    Changes in disturbance regimes can influence the structure of 
forests at multiple spatial scales (Reilly, et al., 2018). Within 
forest stands, more frequent fire will likely decrease tree density in 
dry forests, and open savannas may increase in area. Forest 
understories may shift from being duff- or forb-dominated to shrub- or 
grass-dominated. Tree canopy base heights will likely increase as 
frequent fires remove lower branches. Across forested landscapes (i.e., 
among stands), fire directly influences the spatial mosaic of forest 
patches (Agee 1993). More extreme fire conditions with climate change 
may initially lead to larger and more frequent fires, resulting in 
larger burn patch sizes and greater landscape homogeneity (Harvey, et 
al., 2016a). More frequent severe fire will likely decrease forest age, 
the fraction of old-growth forest patches, and the landscape 
connectivity of old-growth forest patches (Baker 1995; McKenzie, et 
al., 2004). However, more frequent low- and mixed-severity fires may 
eventually reduce fuels in drier forest ecosystems (e.g., dry mixed 
conifer), leading to lower-intensity fires and a finer-scale patch 
mosaic (Chmura, et al., 2011).
Effects of climate change on post-fire processes
Forest regeneration
    Changing climate and fire frequency, extent, and severity are 
likely to influence forest regeneration processes, thus affecting the 
structural and compositional trajectories of forest ecosystems. First, 
climate change is expected to affect regeneration through increased 
fire frequency. As fire-free intervals shorten, the time available for 
plants to mature and produce seed before the next fire will be limited. 
Such changes in fire-free intervals can have significant effects on 
post-fire regeneration, because different plants have varied 
adaptations to fire. Species that resprout following fire may decline 
in density, but species that are fire-killed and thus require 
reproduction from seed may be locally eliminated.
    Second, climate change may result in increased fire severity. If 
the size of high-severity fire patches increases, seed sources to 
regenerate these patches will be limited. Regeneration of non-
serotinous species will require long-distance seed dispersal and may be 
slower in large, high-severity patches (Little, et al., 1994; Donato, 
et al., 2009a; Downing, et al., 2019).
    Third, climate change will likely result in increased forest 
drought stress. Warmer temperatures, lower snowpack, and increased 
evapotranspiration will increase summer drought stress. Warmer and 
drier conditions after fire events may cause recruitment failures, 
particularly at the seedling stage (Dodson and Root 2013). In this way, 
fire can accelerate species turnover when climatic conditions are 
unfavorable for establishment of dominant species (Crausbay, et al., 
2017) and seed sources are available for alternative species.
    Regeneration in dry forests in the Northwest (e.g., ponderosa pine) 
may be particularly sensitive to changing climate. Hotter and drier 
sites (e.g., on southwestern aspects) may be particularly at risk for 
regeneration failures (Nitschke, et al., 2012; Dodson and Root 2013; 
Donato, et al., 2016; Rother and Veblen 2017; Tepley, et al., 2017). 
High soil surface temperatures can also cause mortality (Minore and 
Laacke 1992). Forest structure (mainly shade from an existing canopy) 
can ameliorate harsh conditions and allow for regeneration (Dobrowski, 
et al., 2015). However, after high-severity disturbance, dry forests at 
the warm and dry edges of their distribution (ecotones) may convert to 
grasslands or shrublands in a warming climate (Johnstone, et al., 2010; 
Jiang, et al., 2013; Savage, et al., 2013; Donato, et al., 2016; 
Stevens-Rumann, et al., 2017).
    In the Klamath-Siskiyou ecoregion of southwestern Oregon and 
northern California, Tepley, et al., (2017) found that conifer 
regeneration was reduced by low soil moisture after fires. With lower 
soil moisture, greater propagule pressure (smaller high-severity 
patches with more live seed trees) was needed to achieve a given level 
of regeneration. This suggests that, at high levels of climatic water 
deficit, even small high-severity patches are at risk for low post-fire 
conifer regeneration. Successive fires could further limit conifer seed 
sources, thus favoring shrubs and hardwoods.
    Germination of ponderosa pine is favored by moderate temperatures 
and low moisture stress, and survival increases when maximum 
temperatures are warm (but not hot) and when growing season rainfall is 
above average (Petrie, et al., 2016; Rother and Veblen 2017). Empirical 
modeling by Petrie, et al., (2017) projected that, with warming 
temperature in the middle of the twenty-first century, regeneration 
potential of ponderosa pine may increase slightly on many sites. 
However, by the end of the century, with decreased moisture 
availability, regeneration potential in the Northwest decreased by 67% 
in 2060 to 2099 compared to 1910 to 2014. In the eastern Cascade Range 
of Oregon, Dodson and Root (2013) found decreasing ponderosa pine 
regeneration with decreasing elevation and moisture availability, 
suggesting that moisture stress would limit regeneration.
    Several studies in the Rocky Mountains have also found decreased 
post-fire regeneration with increased water deficits on drier, lower-
elevation sites (Rother, et al., 2015; Donato, et al., 2016; Stevens-
Rumann, et al., 2017; Davis, et al., 2019). Donato, et al., (2016) 
found decreased regeneration of Douglas-fir 24 years after fire on 
drier, lower-elevation sites compared to more mesic sites at higher 
elevations. Regeneration declined with higher burn severity and was 
minimal beyond 100 to 200 m from a seed source. Similarly, Harvey, et 
al., (2016c) found that post-fire tree seedling establishment decreased 
with greater post-fire drought severity in subalpine forests of the 
northern U.S. Rocky Mountains; post-fire subalpine fir and Engelmann 
spruce regeneration were both negatively affected by drought. Davis, et 
al., (2019) modeled post-fire recruitment probability for ponderosa 
pine and Douglas-fir on sites in the Rocky Mountains, and found that 
recruitment probability decreased between 1988 and 2015 for both 
species, suggesting a decline in climatic suitability for post-fire 
tree regeneration.
    In a study of annual regeneration and growth for 10 years following 
wildfire in the eastern Cascade Range of Washington, Littlefield (2019) 
found that establishment rates of lodgepole pine (and other species) 
were highest when growing seasons were cool and moist. A lagged climate 
signal was apparent in annual growth rates, but standardized climate-
growth relationships did not vary across topographic settings, 
suggesting that topographic setting did not decouple site conditions 
from broader climatic trends to a degree that affected growth patterns. 
These results underscore the importance of favorable post-fire climatic 
conditions in promoting robust establishment and growth while 
highlighting the importance of topography and stand-scale processes 
(e.g., seed availability and delivery). Although concerns about post-
fire regeneration failure may be warranted under some conditions, 
failure is not a general phenomenon in all places and at all times 
(Littlefield 2019).
    If warming climate trends continue as projected, without (or even 
with) tree planting, loss of forests may occur on the driest sites in 
the Northwest (Donato, et al., 2016; Harvey, et al., 2016c; Stevens-
Rumann, et al., 2017), particularly east of the Cascade crest and in 
southwestern Oregon. Individual drought years are not likely to alter 
post-fire successional pathways, especially if wet years occur between 
dry years (Tepley, et al., 2017; Littlefield 2019). Recruitment of 
conifers following a disturbance can require years to decades in the 
Northwest (Little, et al., 1994; Shatford, et al., 2007; Tepley, et 
al., 2014). Thus, shrubs or grasses may dominate during drought 
periods, but conifers could establish and overtop shrubs and grasses 
during wetter and cooler periods (Dugan and Baker 2015; Donato, et al., 
2016).
Management actions
    More frequent and larger wildfires in Northwest forests will likely 
be a major challenge facing resource managers of public and private 
lands in future decades (Peterson, et al., 2011a). Adapting forest 
management to climate change will help forest ecosystems transition to 
new conditions, while continuing to provide timber, water, recreation, 
habitat, and other benefits to society. Starting the process of 
adaptation now, before the marked increase in wildfire expected by the 
mid twenty-first century, will likely improve options for successful 
outcomes. Fortunately, some current forest management practices, 
including stand density management and surface fuel reduction in dry 
forests, and control of invasive species, are ``climate smart'' because 
they increase resilience to changing climate and disturbances 
(Peterson, et al., 2011a; Peterson, et al., 2011b).
    Resource managers will likely be unable to prevent increasing 
broad-scale trends in area burned with climate change, but fuel 
treatments can decrease fire intensity and severity locally (Agee and 
Skinner 2005; Peterson, et al., 2005). In drought- and fire-prone 
forests of the Northwest (e.g., ponderosa pine and dry mixed-conifer 
forests east of the Cascades and in southwestern Oregon), reducing 
forest density can decrease crown fire potential (Agee and Skinner 
2005; Safford, et al., 2012; Martinson and Omi 2013; Shive, et al., 
2013), and negative effects of drought on tree growth (Clark, et al., 
2016; Sohn, et al., 2016). Even in wetter forest types, reducing stand 
density can increase water availability, tree growth, and tree vigor by 
reducing competition (Roberts and Harrington 2008). Decreases in forest 
stand density, coupled with hazardous fuel treatments, can also 
increase forest resilience to wildfire in dry forest types (Agee and 
Skinner 2005; Stephens, et al., 2013; Hessburg, et al., 2015).
    In dry forests, forest thinning prescriptions may need to reduce 
forest density to increase forest resistance and resilience to fire, 
insects, and drought (Peterson, et al., 2011a; Sohn, et al., 2016). For 
example, in anticipation of a warmer climate and increased fire 
frequency, managers in Okanogan-Wenatchee National Forest in eastern 
Washington are currently basing stocking levels for thinning and fuel 
treatments on the next driest forest type. Thinning and fuel treatments 
could also be prioritized in (1) locations where climate change 
effects, particularly increased summer drought, are expected to be most 
pronounced (e.g., on south-facing slopes); (2) high-value habitats; and 
(3) high-risk locations such as the wildland-urban interface. Fuel 
treatments must be maintained over time to remain effective (Agee and 
Skinner 2005; Peterson, et al., 2005). Insufficient financial 
resources, agency capacity constraints, and air quality constraints on 
prescribed burning are harsh realities that will in most cases limit 
the extent of fuel treatments (Melvin 2018), necessitating strategic 
implementation of treatments in locations where fuel reduction will 
maximize ecological, economic, and political benefits.
    Fewer options exist for reducing fire severity in wetter, high-
elevation and coastal forests of the Northwest, historically 
characterized by infrequent, stand-replacement fire regimes (Halofsky, 
et al., 2018b). In these ecosystems, thinning and hazardous fuel 
treatments are unlikely to significantly affect fire behavior, because 
fires typically occur under extreme weather conditions (i.e., during 
severe drought). However, managers may consider installing fuel breaks 
around high-value resources, such as municipal watersheds, key wildlife 
habitats, and valuable infrastructure, to reduce fire intensity and 
facilitate fire suppression efforts (Syphard, et al., 2011). In 
addition, ecosystem resilience to a warmer climate is likely to improve 
by promoting landscape heterogeneity with diverse species and stand 
structures, and by reducing the effects of existing non-climatic 
stressors on ecosystems, such as landscape fragmentation and invasive 
species (Halofsky, et al., 2018b).
    The future increase in fire will put late-successional forest at 
risk, potentially reducing habitat structures (large trees, snags, 
downed wood) that are important for many plant and animal species. In 
dry forests, some structures can be protected from fire by thinning 
around them and reducing organic material at their base (Halofsky, et 
al., 2016). To increase habitat quality and connectivity, increasing 
the density of these structures may be particularly effective in 
younger forests, especially where young forests are in close proximity 
to late-successional forest.
    Regeneration failures after fire are a risk with changing climate, 
particularly for drier forests. A primary method to help increase 
natural post-fire regeneration is to increase seed sources by both 
reducing fire severity (through fuel treatments and prescribed fire) 
and increasing the number of live residual trees (Dodson and Root 
2013). In areas adjacent to green trees, natural regeneration may be 
adequate. In locations farther than 200 m from living trees, managers 
may want to supplement natural regeneration with planting where costs 
are not prohibitive because of remoteness or topography (North, et al., 
2019). Where post-fire planting is desirable, managers may consider 
changes from current practices. For example, they may want to consider 
lowering stocking density and increasing the spatial heterogeneity of 
plantings to increase resilience to fire and drought (North, et al., 
2019). Planting seedlings on cooler, wetter microsites will also likely 
help to increase survival (Rother, et al., 2015). Managers may also 
consider different genetic stock than has been used in the past to 
increase seedling survival (Chmura, et al., 2011). Tools such as the 
Seedlot Selection Tool (https://seedlotselectiontool.org/sst) can help 
identify seedling stock that will be best adapted to a given site in 
the future.
    In general, regeneration in the driest topographic locations may be 
slower in a warming climate than it has been in the past. Some areas 
are likely to convert from conifer forest to hardwoods or non-forest 
(shrubland or grassland) vegetation, particularly at lower treeline. 
Managers may need to consider where they will try to forestall change 
and where they may need to allow conversions to occur (Rother, et al., 
2015).
    Finally, collaboration among many groups-land management agencies, 
rural communities, private forest landowners, Tribes, and conservation 
groups--is needed for successful adaptation to the effects of a warmer 
climate on wildfire (Joyce, et al., 2009; Spies, et al., 2010; Stein, 
et al., 2013). Working together will ensure a common vision for 
stewardship of forest resources, and help produce a consistent, 
effective strategy for fuel treatments and other forest practices 
across large forest landscapes.
Uncertainties and future research needs
    Changing disturbance regimes will accompany climate change in the 
Northwest (Tables 1, 2 and 3). However, uncertainties remain, many 
related to future human behavior relative to greenhouse gas emissions, 
the rate and magnitude of climate change, and effects on vegetation and 
fire regimes. Human activities will also affect fire through land use 
and management, fire ignitions, and fire suppression, all of which are 
difficult to predict. For example, societal priorities may change, 
affecting forest management and vegetation conditions. Fire suppression 
is likely to continue in the future, but may become less effective 
under more extreme fire weather conditions (Fried, et al., 2008), 
affecting area burned.
    Historical relationships between climate and fire in the Northwest 
indicate that the ENSO and PDO can influence area burned. However, it 
is unclear how climate change will affect these modes of climatic 
variability or how they may interact with the effects of climate change 
on natural resources; global climate models differ in how these cycles 
are represented and in how they are projected to change. The frequency 
and persistence of high blocking ridges in summer (which divert 
moisture from the region) will also affect fire frequency and severity 
in the region, and climate change may affect the frequency of these 
blocking ridges (Lupo, et al., 1997).
    The lack of fire over the last few centuries in forests with low-
frequency and high-severity fire regimes creates uncertainty in fire 
projections for the future. Although the likelihood of a large fire 
event in these forests is low, if large fire events start occurring as 
frequently as some models project (e.g., Rogers, et al., 2011), then 
major ecological changes are likely. Updating models as events occur 
over time may help to adjust projections in the future.
    Shifts in forest productivity and composition are highly likely to 
occur with climate change in the region, which could affect fuel 
levels. However, it is uncertain how carbon dioxide fertilization will 
interact with moisture stress and disturbance regimes to affect forest 
productivity (Chmura, et al., 2011) and thus fuel levels. Increased 
forest productivity, combined with hot and dry conditions in late 
summer, would likely produce large and severe fires (Rogers, et al., 
2011). Continued research on the potential effects of carbon dioxide 
fertilization on forest productivity will help to improve fire severity 
projections.
    Other high-priority research needs include determining forest 
ecosystem response to multiple disturbances and stressors (e.g., 
effects of repeated fire and drought on forest regeneration), and 
determining post-fire regeneration controls across a range of forest 
types and conditions. Identifying locations where vegetation type 
shifts (e.g., forest to woodland or shrubland) are likely because of 
changing climate and disturbance regimes will help managers determine 
where to prioritize efforts. Managers will also benefit from evaluation 
of pre- and post-fire forest treatments to increase resilience or 
facilitate transition to new conditions in different forest types.
    Although this synthesis is focused on the effects of climate change 
on fire and vegetation, many secondary effects are expected for natural 
resources and ecosystem services, some of which are already occurring. 
Climate change is reducing snowpack (Mote, et al., 2018) and affecting 
hydrologic function in the Northwest, including more flooding in winter 
and lower streamflow in summer (Luce and Holden 2009). Higher stream 
temperatures are degrading cold-water fish habitat (Isaak, et al., 
2010). Altered vegetation and snowpack are expected to have long-term 
implications for animal habitat (Singleton, et al., 2019). Recreational 
opportunities (Hand, et al., 2019), infrastructure on public lands 
(Furniss, et al., 2018), and cultural values (Davis 2018) will likely 
also be affected by changing climate, fire, and other disturbances.
    Uncertainties associated with climate change require an 
experimental approach to resource management; using an adaptive 
management framework can help address uncertainties and adjust 
management over time. In the context of climate change adaptation, 
adaptive management involves: (1) defining management goals, 
objectives, and timeframes; (2) analyzing vulnerabilities and 
determining priorities; (3) developing adaptation options; (4) 
implementing plans and projects; and (5) monitoring, reviewing, and 
adjusting (Millar, et al., 2014). Scientists and managers can work 
together to implement an adaptive management framework and ensure that 
the best available science is used to inform management actions on the 
ground.
Availability of data and materials
    Please contact the corresponding author for data requests.
Acknowledgements
    We thank D. Donato, L. Evers, B. Glenn, M. Johnson, V. Kane, M. 
Reilly, and three anonymous reviewers for providing helpful suggestions 
that improved the manuscript. P. Loesche provided valuable editorial 
assistance, J. Ho assisted with literature compilation and figures, and 
R. Norheim developed several maps.
Funding
    Funding was provided by the U.S. Department of the Interior, 
Northwest Climate Adaptation Science Center, and the U.S. Forest 
Service Pacific Northwest Research Station and Office of Sustainability 
and Climate. None of the funding bodies played any role in the design 
of the study, interpretation of data, or writing the manuscript.
Author information
Affiliations
    U.S. Department of Agriculture, Forest Service, Pacific Northwest 
    Research Station, Olympia Forestry Sciences Lab, 3625 93rd Avenue 
    SW, Olympia, Washington, 98512, USA
Jessica E. Halofsky
    School of Environmental and Forest Sciences, College of the 
    Environment, University of Washington, Box 352100, Seattle, 
    Washington, 98195-2100, USA
David L. Peterson & Brian J. Harvey
Contributions
    J.H. led the study and contributed to information collection, 
analysis, and interpretation, and co-wrote the paper. D.P. contributed 
to information collection, analysis, and interpretation, and co-wrote 
the paper. B.H. contributed to information collection, analysis, and 
interpretation, and co-wrote the paper. All authors read and approved 
the final manuscript.
Authors' information
    J. Halofsky is a research ecologist; D. Peterson is a professor of 
forest biology; B. Harvey is an assistant professor of forest ecology.
Corresponding author
    Correspondence to Jessica E. Halofsky.
Ethics declarations
Ethics approval and consent to participate
    Not applicable.
Consent for publication
    Not applicable.
Competing interests
    The authors declare that they have no competing interests.
    Received: 20 March 2019 Accepted: 11 November 2019.
    Published online: 27 January 2020.
Additional information
Publisher's Note
    Springer Nature remains neutral with regard to jurisdictional 
claims in published maps and institutional affiliations.

 
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                               Article 3
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

[https://www.nature.com/articles/nature13179]
Nature
Letter
Increasing CO2 threatens human nutrition
Samuel S. Myers,1, 2 Antonella Zanobetti,\1\ Itai Kloog,\3\ 
Peter Huybers,\4\ Andrew D.B. Leakey,\5\ Arnold J. Bloom,\6\ Eli 
Carlisle,\6\ Lee H. Dietterich,\7\ Glenn Fitzgerald,\8\ Toshihiro 
Hasegawa,\9\ N. Michele Holbrook,\10\ Randall L. Nelson,\11\ Michael J. 
Ottman,\12\ Victor Raboy,\13\ Hidemitsu Sakai,\9\ Karla A. Sartor,\14\ 
Joel Schwartz,\1\ Saman Seneweera,\15\ Michael Tausz,\16\ and Yasuhiro 
Usui \9\
---------------------------------------------------------------------------
    \1\ Department of Environmental Health, Harvard School of Public 
Health, Boston, Massachusetts, 02215, USA.
    \2\ Harvard University Center for the Environment, Cambridge, 
Massachusetts 02138, USA.
    \3\ The Department of Geography and Environmental Development, Ben-
Gurion University of the Negev, PO Box 653, Beer Sheva, Israel.
    \4\ Department of Earth and Planetary Science, Harvard University, 
Cambridge, Massachusetts 02138, USA.
    \5\ Department of Plant Biology and Institute for Genomic Biology, 
University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, 
USA.
    \6\ Department of Plant Sciences, University of California at 
Davis, Davis, California 95616, USA.
    \7\ University of Pennsylvania, Department of Biology, 
Philadelphia, Pennsylvania 19104, USA.
    \8\ Department of Environment and Primary Industries, Horsham, 
Victoria 3001, Australia.
    \9\ National Institute for Agro-Environmental Sciences, Tsukuba, 
Ibaraki, 305-8604, Japan.
    \10\ Department of Organismic and Evolutionary Biology, Harvard 
University, Cambridge, Massachusetts 02138, USA.
    \11\ United States Department of Agriculture Agricultural Research 
Service, Soybean/Maize Germplasm, Pathology, and Genetics Research 
Unit, Department of Crop Sciences, University of Illinois, Urbana, 
Illinois 61801, USA.
    \12\ School of Plant Sciences, University of Arizona, Tucson, 
Arizona 85721, USA.
    \13\ United States Department of Agriculture Agricultural Research 
Service, Aberdeen, Idaho 83210, USA.
    \14\ The Nature Conservancy, Santa Fe, New Mexico 87544, USA.
    \15\ Department of Agriculture and Food Systems, Melbourne School 
of Land and Environment, The University of Melbourne, Creswick, 
Victoria 3363, Australia.
    \16\ Department of Forest and Ecosystem Science, Melbourne School 
of Land and Environment, The University of Melbourne, Creswick, 
Victoria 3363, Australia.

    Dietary deficiencies of zinc and iron are a substantial global 
public health problem. An estimated two billion people suffer these 
deficiencies,\1\ causing a loss of 63 million life-years 
annually.2, 3 Most of these people depend on C3 
grains and legumes as their primary dietary source of zinc and iron. 
Here we report that C3 grains and legumes have lower 
concentrations of zinc and iron when grown under field conditions at 
the elevated atmospheric CO2 concentration predicted for the 
middle of this century. C3 crops other than legumes also 
have lower concentrations of protein, whereas C4 crops seem 
to be less affected. Differences between cultivars of a single crop 
suggest that breeding for decreased sensitivity to atmospheric 
CO2 concentration could partly address these new challenges 
---------------------------------------------------------------------------
to global health.

    In the 1990s, several investigators found that elevated atmospheric 
CO2 concentration (hereafter abbreviated to 
[CO2]) decreased the concentrations of zinc, iron and 
protein in grains of wheat,4-7 barley \5\ and rice \8\ grown 
in controlled-environment chambers. However, subsequent studies failed 
to replicate these results when plants were grown in open-top chambers 
and free-air CO2 enrichment (FACE) experiments. A previous 
study \9\ found no effect of [CO2] on the concentrations of 
zinc or iron in rice grains grown under FACE and suggested that the 
earlier findings had been influenced by `pot effects', by which a small 
rooting volume led to nutrient dilution at the root-soil interface. Of 
the more recent studies,10-13 most have indicated lower 
elemental concentrations in soybeans,\10\ sorghum,\10\ potatoes,\11\ 
wheat \12\ or barley \13\ grown at elevated [CO2], but with 
the exception of iron in one study on wheat,\12\ these results were 
statistically insignificant, perhaps because of small sample sizes.
    Small sample sizes have limited the statistical power of individual 
studies of many aspects of plant responses to elevated 
[CO2], and metaanalyses involving larger samples of 
genotypes, environmental conditions and experimental locations have 
been important in resolving which elements of plant function respond 
reliably to altered [CO2].14, 15 A recent meta-
analysis of published data concluded that only sulphur is decreased in 
grains grown at elevated [CO2].\16\
    Here we report findings froma meta-analysis of newly acquired data 
from 143 comparisons of the edible portions of crops grown at ambient 
and elevated [CO2] fromseven different FACE experimental 
locations in Japan, Australia and the United States involving six food 
crops (see Table 1). We tested the nutrient concentrations of the 
edible portions of rice (Oryza sativa, 18 cultivars), wheat (Triticum 
aestivum, eight cultivars), maize (Zea mays, two cultivars), soybeans 
(Glycine max, seven cultivars), field peas (Pisum sativum, five 
cultivars) and sorghum (Sorghum bicolor, one cultivar). In all, forty-
one genotypes were tested over one to six growing seasons at ambient 
and elevated [CO2], where the latter was in the range 546-
586 p.p.m. across all seven study sites. Collectively, these 
experiments contribute more than tenfold more data regarding both the 
zinc and iron content of the edible portions of crops grown under FACE 
conditions than is currently available in the literature. Consistent 
with earlier meta-analyses of other aspects of plant function under 
FACE conditions.14, 15 we considered the response 
comparisons observed from different species, cultivars and stress 
treatments and from different years to be independent. The natural 
logarithm of the mean response ratio (r = response in elevated 
[CO2]/response inambient [CO2]) was used as 
themetric for all analyses. Meta-analysis was used to estimate the 
overall effect of elevated [CO2] on the concentration of 
each nutrient in a particular crop and to determine the significance of 
this effect (see Methods).
    We found that elevated [CO2] was associated with 
significant decreases in the concentrations of zinc and iron in all 
C3 grasses and legumes (Fig. 1 and Extended Data Table 1). 
For example, wheat grains grown at elevated [CO2] had 9.3% 
lower zinc (95% confidence interval (CI) ^12.7% to ^5.9%) and 5.1% 
lower iron (95% CI ^6.5% to ^3.7%) than those grown at ambient 
[CO2]. We also found that elevated [CO2] was 
associated with lower protein content in C3 grasses, with a 
6.3% decrease (95% CI ^7.5% to ^5.2%) inwheat grains and a 7.8% 
decrease (95% CI ^8.9% to ^6.8%) in rice grains. Elevated 
[CO2] was associated with a small decrease in protein in 
fieldpeas, and therewas no significant effect in soybeans or 
C4 crops (Fig. 1 and Extended Data Table 1).
    In addition to our own observations, we obtained data from 10 of 11 
previously-published studies investigating nutrient changes in the 
edible portion of food crops (Extended Data Table 6) and combined these 
data with our own observations in a larger meta-analysis. Analysis of 
our results combined with previously published FACE data (Extended Data 
Table 2), or combined with previously published data from both FACE and 
chamber experiments (Extended Data Table 3), was consistent with the 
results obtained using only our new data. Combining our data with 
previously published data did not alter the significance or 
substantially alter the effect size of the nutrient changes for any 
crop or any nutrient.
    In addition to nutrient concentrations, we also measured phytate, a 
phosphate storage molecule present in most plants that inhibits the 
absorption of dietary zinc in the human gut.\17\ We had no a priori 
reason to assume that phytate concentrations would change in response 
to rising [CO2]. However, formulae for calculating absorbed, 
or bioavailable, zinc depend on both the amount of dietary zinc and the 
amount of dietary phytate consumed,\17\ making it important to 
interpret changes in zinc concentration in the context of possible 
changes in phytate. Phytate content decreased significantly at elevated 
[CO2] only in wheat (P<0.01). This decrease might offset 
some of the declines in zinc for this particular crop, although the 
decrease was slightly less than half of the decrease in zinc. For other 
crops examined, however, the lack of a concurrent decrease in 
phytatemay further exacerbate problemsof zinc deficiency.

                              Table 1 D Characteristics of agricultural experiments
----------------------------------------------------------------------------------------------------------------
                                                                                                     CO2 ambient/
      Crops             Country           Treatments used     Years grown   Number of    Number of     elevated
                                                                            replicates   cultivars     (p.p.m.)
----------------------------------------------------------------------------------------------------------------
Wheat
  Site 1          Australia           2 water levels, 2         2007-2010            4            8  382/546-550
                                       nitrogen treatments,
                                       2 sowing times
  Site 2          Australia           1 water level, 1          2007-2009            4            1  382/546-550
                                       nitrogen treatment, 2
                                       sowing times
Field peas        Australia           2 water levels                 2010            4            5  382/546-550
Rice
  Site 1          Japan               1 nitrogen treatment,     2007-2008            3            3  376-379/570-
                                       2 warming treatments                                                  576
  Site 2          Japan               3 nitrogen treatments,         2010            4           18      386/584
                                       2 warming treatments
Maize             United States       2 nitrogen treatments          2008            4            2      385/550
Soybeans          United States       1 treatment             2001, 2002,            4            7  372-385/550
                                                              2004, 2006-
                                                                     2008
Sorghum           United States       2 water levels            1998-1999            4            1  363-373/556-
                                                                                                             579
----------------------------------------------------------------------------------------------------------------
`Number of replicates' refers to the number of identical cultivars grown under identical conditions in the same
  year and location but in separate FACE rings.

    The global [CO2] in the atmosphere is expected to reach 
550 p.p.m. in the next 40-60 years, even if further actions are taken 
to decrease emissions.\18\ At these concentrations, we find that the 
edible portions of many of the key crops for human nutrition have 
decreased nutritional value when compared with the same plants grown 
under identical conditions but at the present ambient [CO2]. 
Analysis of the United Nations' Food and Agriculture Organization food 
balance sheets reveals that in 2010 roughly 2.3 billion people were 
living in countries whose populations received at least 60% of their 
dietary zinc and/or iron from C3 grains and legumes, and 1.9 
billion lived in countries that received at least 70% of one or both of 
these nutrients from these crops (Extended Data Table 5). Reductions in 
the zinc and iron content of the edible portion of these food crops 
will increase the risk of zinc and iron deficiencies across these 
populations and will add to the already considerable burden of disease 
associated with them.
    The implications of decreased protein concentrations in non-
leguminous C3 crops are less clear. From a study of adult 
men and women in the United States, there is strong evidence that the 
substitution of dietary carbohydrate for dietary protein increased the 
risk of hypertension, lipid disorders, and 10 year coronary heart 
disease risk.\19\ For the developing world, minimum protein 
requirements for different demographic groups are an area of active 
research and debate.\20\ For countries such as India, however, inwhich 
up to \1/3\ of the rural population is thought to be at risk of not 
meeting protein requirements \21\ and in which most protein comes in 
the form of C3 grains,\21\ decreased protein content in non-
leguminous C3 crops may have serious consequences for public 
health.
    Whereas zinc and iron were significantly decreased in all 
C3 crops tested, only iron in maize was observed to 
decreaseamong the C4 crops. No changes were found in 
sorghum. That zinc and iron declines were notable in C3 
crops but less so in C4 crops is consistent with differences 
in physiology. C4 crops concentrate CO2 
internally, which results in photosynthesis being CO2-
saturated even under ambient [CO2] conditions, leading to no 
stimulation of photosynthetic carbon assimilation at elevated 
[CO2] levels under mesic growing conditions.\22\ Our finding 
that protein content was less affected in legumes than in other 
C3 crops is also physiologically consistent with the general 
ability of leguminous crops to match the stimulation of photosynthetic 
carbon gain at elevated [CO2] with greater nitrogen 
fixation, to maintain tissue carbon:nitrogen (C:N) ratios.\23\ In 
contrast, most temperate non-legume C3 crops are generally 
unable to extract and assimilate sufficient nitrogen from soils to 
maintain tissue C:N ratios.24, 25
    Little is known about the mechanism(s) responsible for the decline 
in nutrient concentrations associatedwith elevated [CO2]. 
Someauthors have proposed `carbohydrate dilution', by which 
CO2-stimulated carbohydrate production by plants dilutes the 
rest of the grain components.\26\ To test this hypothesis, we measured 
concentrations of additional elements for all crops except wheat 
(Extended Data Table 4). Our findings were inconsistent with 
carbohydrate dilution operating alone. If only passive dilution of 
nutrients were occurring, we would have expected to see very similar 
changes in the concentration of each nutrient tested for a given crop. 
In contrast, we found that elemental changes in the individual crops 
are distinct from each other. For example, in rice grains (Extended 
Data Table 4) the decrease in zinc concentrations associated with 
elevated [CO2] was significantly different from the 
decreases in the concentrations of copper (P50.001), calcium (P50.001), 
boron (P50.001) and phosphate (P=0.010). This heterogeneous response 
was also observed in recent analyses reviewing possible mechanisms for 
nutrient changes in both edible and non-edible plant tissues grown at 
elevated [CO2].\27\ It also seems that the mechanism(s) 
causing these changes operate distinctly in different species. In one 
instance, for example, we found boron to be significantly decreased in 
soybeans (P50.001), whereas itwas significantly elevated in rice grains 
(P50.001). Although these differences may, in part, have derived from 
different environmental conditions, they suggest that the 
mechanismismore complex than carbohydrate dilution alone. Of all the 
elements, changes in nitrogen content at elevated [CO2] have 
been themost studied, and inhibition of photorespiration and malate 
production,\24\ carbohydrate dilution,\26\ slower uptake of nitrogen in 
roots \25\ and decreased transpiration-driven mass flow of nitrogen \7\ 
may all be significant.
Figure 1 D Percentage change in nutrients at elevated [CO2] 
        relative to ambient [CO2]
        [GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
        
          Numbers in parentheses refer to the number of comparisons in 
        which replicates of a particular cultivar grown at a specific 
        site under one set of growing conditions in 1 year at elevated 
        [CO2] have been pooled and for which mean nutrient 
        values for these replicates are compared with mean values for 
        identical cultivars under identical growing conditions except 
        grown at ambient [CO2]. In most instances, data from 
        four replicates were pooled for each value, meaning that eight 
        experiments were combined for each comparison (see Table 1 for 
        details of experiments). Error bars represent 95% confidence 
        intervals of the estimates.
Figure 2 D Percentage change (with 95% confidence intervals) in 
        nutrients at elevated [CO2] relative to ambient 
        [CO2], by cultivar
        [GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
        
          a, Zinc; b, iron; c, protein.

    We also examined the effects of elevated [CO2] on zinc, 
iron and protein content as a function of cultivar when data were 
available (Fig. 2). Whereas most crops showed negligible differences 
across cultivars, concentrations of zinc and iron across rice cultivars 
varied substantially (P=0.04 and P=0.03, respectively; Fig. 2a, b). 
Such differences between cultivars suggest a basis for breeding rice 
cultivars whose micronutrient levels are less vulnerable to increasing 
[CO2]. Similar effects may occur in other crops, given that 
the statistical power of many of our other intercultivar tests was 
limited by sample size. We note, however, that such breeding programmes 
will not be a panacea for many reasons including the affordability of 
improved seeds and the numerous criteria used by farmers in making 
planting decisions that include taste, tradition, marketability, 
growing requirements and yield. In addition, as has been noted 
previously, there are likely to be trade-offs with respect to yield and 
other performance characteristics when breeding for increased zinc and 
iron content.\28\
    The public health implications of global climate change are 
difficult to predict, and we expect many surprises. The finding that 
raising atmospheric [CO2] lowers the nutritional value of 
C3 food crops is one such surprise that we can now better 
predict and prepare for. In addition to efforts to limit increases in 
[CO2], it may be important to develop breeding programmes 
designed to decrease the vulnerability of key crops to these changes. 
Nutritional analysis of which human populations are most vulnerable 
todecreased dietary availability of zinc, iron and protein from 
C3 crops could help to target response efforts, including 
breeding decreased sensitivity to elevated [CO2], 
biofortification, and supplementation.
Methods Summary
    We examined the response of nutrient levels to elevated atmospheric 
[CO2] for the edible portions of rice (Oryza sativa, 18 
cultivars), wheat (Triticum aestivum, eight cultivars), maize (Zea 
mays, two cultivars), soybeans (Glycine max, seven cultivars), field 
peas (Pisum sativum, five cultivars) and sorghum (Sorghum bicolor, one 
cultivar). The six crops were grown under FACE conditions; in all six 
experiments the elevated [CO2] was in the range 546-586 
p.p.m.
    In accordance with methods described previously,14, 15 
the natural logarithm of the response ratio (r=response in elevated 
[CO2]/response in ambient [CO2]) was used as the 
metric for analyses and is reported as the mean percentage change 
(100(r^1)) at elevated [CO2]. Consistent with these earlier 
analyses of multiple species grown under FACE conditions, the responses 
of different species, cultivars and stress treatments and from 
different years of the FACE experiments were considered to be 
independent and suited to meta-analytic analysis.\14\
    The meta-analysis was designed to estimate the effect of elevated 
[CO2] on the concentration of each nutrient in a particular 
crop and to determine the significance of this effect relative to a 
null hypothesis of no change. All tests were conducted as two-sided; 
that is, not specifying which direction the nutrient concentrations 
were expected to change under elevated [CO2]. Meta-analysis 
was conducted with a linear mixed model.
    Parameter estimates were obtained by the restricted maximum-
likelihood method, a standard approach for analysing repeated 
measurements \29\ that, in our case, were of nutrient concentrations at 
the time of harvest. Results for all analyses are reported as the best 
estimate of percentage changes in the concentration of nutrients along 
with the 95% confidence intervals associated with each estimate. Two-
tailed P values are also reported.
Online Content
    Any additional Methods, Extended Data display items and Source Data 
are available in the online version of the paper; references unique to 
these sections appear only in the online paper.

    Received 25 November 2013; accepted 24 February 2014.
    Published online 7 May 2014.

 
 
 
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Acknowledgements
    We thank L. S. De la Puente, M. Erbs, A. Fangmeier, P. Hogy, M. 
Lieffering, R. Manderscheid, H. Pleijel and S. Prior for sharing data 
from their groups with us; H. Nakamura, T. Tokida, C. Zhu and S. 
Yoshinaga for contributions to the rice FACE project; and M. Hambidge, 
W. Willett, D. Schrag, K. Brown, R. Wessells, N. Fernando, J. Peerson 
and B. Kimball for reviews of earlier drafts or conceptual 
contributions to this project. V.R. thanks A.L. Harvey for her efforts 
in producing the phytate data included here. The National Agriculture 
and Food Research Organization (Japan) provided the grain samples of 
some rice cultivars. We thank the following for financial support of 
this work: the Bill & Melinda Gates Foundation; the Winslow Foundation; 
the Commonwealth Department of Agriculture (Australia), the 
International Plant Nutrition Institute, (Australia), the Grains 
Research and Development Corporation (Australia), the Ministry of 
Agriculture, Forestry and Fisheries (Japan); the National Science 
Foundation (NSF IOS-08-18435); USDA NIFA 2008-35100-044459; research at 
SoyFACE was supported by the U.S. Department of Agriculture 
Agricultural Research Service; Illinois Council for Food and 
Agricultural Research (CFAR); Department of Energy's Office of Science 
(BER) Midwestern Regional Center of the National Institute for Climatic 
Change Research at Michigan Technological University, under Award 
Number DEFC02-06ER64158; and the National Research Initiative of 
Agriculture and Food Research Initiative Competitive Grants Program 
Grant no. 2010-65114-20343 from the USDA National Institute of Food and 
Agriculture. Early stages of this work received support from Harvard 
Catalyst The Harvard Clinical and Translational Science Center 
(National Center for Research Resources and the National Center for 
Advancing Translational Sciences, National Institutes of Health Award 
8UL1TR000170-05).
Author Contributions
    S.S.M. conceived the overall project and drafted the manuscript. 
A.Z., I.K., J.S. and P.H. performed statistical analyses. P.H. and 
A.D.B.L. provided substantial input into methods descriptions. A.J.B., 
E.C. and V.R. analysed grain samples for nutrient content. G.F., T.H., 
A.D.B.L., R.L.N., M.J.O., H.S., S.S., M.T. and Y.U. conducted FACE 
experiments and supplied grain for analysis. N.M.H. and P.H. assisted 
with elements of experimental design. K.A.S. and L.H.D. assisted with 
data collection and analysis. All authors contributed to manuscript 
preparation.
Author Information
    Reprints and permissions information is available at 
www.nature.com/reprints. The authors declare no competing financial 
interests. Readers are welcome to comment on the online version of the 
paper. Correspondence and requests formaterials should be addressed to 
S.S.M. ([email protected]).
Methods
    We examined the response of nutrient levels to elevated atmospheric 
[CO2] for the edible portions of rice (Oryza sativa, 18 
cultivars), wheat (Triticum aestivum, eight cultivars), maize (Zea 
mays, two cultivars), soybeans (Glycine max, seven cultivars), field 
peas (Pisum sativum, five cultivars) and sorghum (Sorghum bicolor, one 
cultivar). The six crops were grown under FACE conditions; in all six 
experiments, the elevated [CO2] was in the range 546-586 
p.p.m. (see the Agricultural Methods section below for details 
associated with individual trials).
    Statistics. In accordance with methods described 
previously,14, 15 the natural logarithm of the response 
ratio (r=response in elevated [CO2]/response in ambient 
[CO2]) was used as the metric for analyses and is reported 
as the mean percentage change (100(r^1)) at elevated [CO2]. 
Consistent with these earlier analyses of multiple species grown under 
FACE conditions, the responses of different species, cultivars and 
stress treatments and from different years of the FACE experiments were 
considered to be independent and suited to meta-analytic analysis14.
    The meta-analysis was designed to estimate the overall effect of 
elevated [CO2] on the concentration of each nutrient in a 
particular crop and to determine the significance of this effect 
relative to a null hypothesis of no change. All tests were conducted as 
two-sided--not specifying which direction the nutrient concentrations 
were expected to change under elevated [CO2]--to make the 
analysis as general as possible. Meta-analysis was conducted with a 
linear mixed model. A random intercept was included for each 
comparison, representing nutrient level variability unrelated to 
[CO2] that was common to both treatment groups. Additional 
analyses indicated that the effect of [CO2] on zinc 
concentration in rice was modified by cultivar and amount of nitrogen 
application, suggesting systematic variations across the pooled 
analysis of rice, and for these samples it was shown that the effect on 
zinc concentration was still significant when including interactions 
terms for cultivar and nitrogen. No other significant modifications of 
the [CO2] effect were identified. We tested whether changes 
in different nutrients for particular crops were statistically 
different from each other, as has been described.\30\ To address the 
issue of multiple comparisons when testing for differences between 
cultivars within a crop, we multiplied the P value by the number of 
independent comparisons. This approach follows the so-called Bonferroni 
correction and is conservative in the sense of biasing the P values 
high, but still shows that individual test results are significant 
despite their having been selected from multiple tests.
    Parameter estimates were obtained by the restricted maximum-
likelihood method, a standard approach for analysing repeated 
measurement data \29\ that, in our case, were of nutrient 
concentrations at time of harvest. Results for all analyses are 
reported as the best estimate of percentage changes in the 
concentration of nutrients along with the 95% confidence intervals 
associated with each estimate. Two-tailed P values are also reported.
    When combining our data with previously published data, we defined 
outliers as pairs in which the difference between an observation at 
ambient [CO2] and elevated [CO2] was at least 
three times the standard deviation from the mean differences for that 
crop and nutrient type when calculated using all observations. Using 
this criterion, we excluded a total of two pairs of previously 
published data fromall analyses; these included one observation of iron 
in rice and one observation of zinc in potato.
    Agricultural methods. Rice (Oryza sativa, 18 cultivars), wheat 
(Triticum aestivum, eight cultivars), maize (Zea mays, two cultivars), 
soybeans (Glycine max, seven cultivars), field peas (Pisum sativum, 
four cultivars) and sorghum (Sorghum bicolor, one cultivar) were grown 
under FACE conditions during daylight hours. The experiments were 
conducted in Australia, Japan and the United States between 1998 and 
2010. Ambient [CO2] ranges were between 363 and 386 p.p.m.; 
elevated [CO2] was between 546 and 584 p.p.m. With the 
exception of soybeans, each experiment involveed multiple cultivars of 
each crop and more than one set of growing conditions. Each experiment 
for each cultivar and set of treatments was replicated four times, with 
the exception of one of the rice sites, for which three replicates were 
performed. These data are summarized in Table 1, and additional details 
of the soil and growing conditions, FACE methods and experimental 
designs have been published for rice,\31\ wheat,\32\ maize,\33\ 
soybeans,\34\ field peas \32\ and sorghum.\35\
    Minerals method. Samples were analysed for minerals by heated 
closed-vessel digestion/dissolution with nitric acid and hydrogen 
peroxide followed by quantification with an inductively coupled plasma 
atomic emission spectrometer.\36\ Nitrogen content was measured by 
flash combustion of the sample coupled with thermal conductivity/
infrared detection of the combustion gases (N2, 
NOX and CO2) with a LECO TruSpec CN Analyzer.\37\ 
Protein values are based on measurement of nitrogen and conversion to 
proteinwith the equation below, where k=5.36 (ref. 38):

    protein (weight %)=knitrogen (weight %)

For phytic acid determination, amodified version of the method of ref. 
39 was used. The accuracy of the method was monitored by the inclusion 
of tissue standards of known and varying levels of phytic acid.\40\
    Dietary calculations. The United Nations Food and Agriculture 
Organization (UNFAO) publishes annual Food Balance Sheets, which 
provide country-specific data on the quantities of 95 `standardized' 
food commodities available for human consumption. Data, expressed in 
terms of dietary energy (kilocalories per person per day) were 
downloaded for 210 countries and territories with available information 
for the period 2003-2007 (available at http://faostat.fao.org). The 
percentage of dietary energy available from C3 grasses 
(wheat, barley, rye, oats, rice and `cereals, other' (excluding 
Eragrostis tef))was calculated globally with estimates weighted by 
national population size (188 countries available; UN 2011; 2012 
revision available at http://esa.un.org/wpp/).
    Dietary intake data from the UNFAO Food Balance Sheets (to year 
2000) and food composition data fromtheUnited States Department of 
Agriculture National Nutrient Database for Standard Reference were used 
to calculate per-person nutrient intake for 95 food items; these were 
shared with us with permission.\41\ This data set was used to calculate 
the contribution of each food itemto total dietary zinc and iron 
intake, and the proportions of all food items derived from 
C3 grains and legumes were summed to identify countries that 
are highly dependent on plant sources of iron and zinc (Extended Data 
Table 5).

 
 
 
30. Schenker, N. & Gentleman, J.F. On judging the significance of
 differences by examining the overlap between confidence intervals. Am.
 Stat. 55, 182-186 (2001).
31. Hasegawa, T.A., et al. Rice cultivar responses to elevated CO2 at
 two free-air CO2 enrichment (FACE) sites in Japan. Funct. Plant Biol.
 40, 148-159 (2013).
32. Mollah, M., Norton, R. & Huzzey, J. Australian Grains Free Air
 Carbon dioxide Enrichment (AGFACE) facility: design and performance.
 Crop Pasture Sci. 60, 697-707 (2009).
33. Markelz, R., Strellner, R. & Leakey, A. Impairment of C4
 photosynthesis by drought is exacerbated by limiting nitrogen and
 ameliorated by elevated CO2 in maize. J. Exp. Bot. 62, 3235-3246
 (2011).
34. Gillespie, K., et al. Greater antioxidant and respiratory metabolism
 in field-grown soybean exposed to elevated O3 under both ambient and
 elevated CO2. Plant Cell Environ. 35, 169-184 (2012).
35. Ottman, M.J., et al. Elevated CO2 increases sorghum biomass under
 drought conditions. New Phytol. 150, 261-273 (2001).
36. Sah, R.N. & Miller, R.O. Spontaneous reaction for acid dissolution
 of biological tissues in closed vessels. Anal. Chem. 64, 230-233
 (1992).
37. AOAC Official Method 972.43. in Official Methods of Analysis of AOAC
 International, 18th edition, Revision 1, 2006 Ch. 12 5-6 (AOAC
 International, 2006).
38. Mosse, J. Nitrogen to protein conversion factor for ten cereals and
 six legumes or oilseeds. A reappraisal of its definition and
 determination. Variation according to species and to seed protein
 content. J. Agric. Food Chem. 38, 18-24 (1990).
39. Haug, W. & Lantzsch, H.J. Sensitive method for the rapid
 determination of phytate in cereals and cereal products. J. Sci. Food
 Agric. 34, 1423-1426 (1983).
40. Raboy, V., et al. Origin and seed phenotype of maize low phytic acid
 1-1 and low phytic acid 2-1. Plant Physiol. 124, 355-368 (2000).
41. Wuehler, S.E., Peerson, J.M. & Brown, K.H. Use of national food
 balance data to estimate the adequacy of zinc in national food
 supplies: methodology and regional estimates. Public Health Nutr. 8,
 812-819 (2005).
 


                                           Extended Data Table 1 D Percentage change in nutrient content at elevated [CO2K] relative to ambient [CO2K]
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Zn (mg/g)                                 Fe (mg/g)                              Protein (mg/g)                          Phytate (g/100g)
                N * (number --------------------------------------------------------------------------------------------------------------------------------------------------------------------
                 of pairs)         %          95% CI        P-value          %          95% CI        P-value          %          95% CI        P-value         %          95% CI      P-value
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
C3 grasses
  Wheat......            64          ^9.3       (^12.7,        <.0001          ^5.1  (^6.5, ^3.7)        <.0001          ^6.3  (^7.5, ^5.2)        <.0001         ^4.2       (^7.5,        0.009
                                                  ^5.9)                                                                                                                       ^0.8)
  Rice.......            31          ^3.3  (^5.0, ^1.7)        <.0001          ^5.2  (^7.6, ^2.9)        <.0001          ^7.8  (^8.9, ^6.8)        <.0001          1.2  (^4.6, 7.4)        0.697
C3 legumes
  Field peas.            10          ^6.8  (^9.8, ^3.8)         0.002          ^4.1  (^6.7, ^1.4)         0.003          ^2.1  (^4.0, ^0.1)         0.039         ^5.8      (^11.5,        0.055
                                                                                                                                                                               0.1)
  Soybeans...            25          ^5.1   (^6.4,^3.9)        <.0001          ^4.1   (^5.8,^2.5)        <.0001           0.5    (^0.4,1.3)         0.267         ^1.3  (^3.7, 1.2)        0.303
C4 grasses
  Maize......             4          ^5.2  (^10.7, 0.6)         0.077          ^5.8       (^10.9,         0.038          ^4.6   (^13.0,4.5)         0.312         ^6.1      (^15.0,        0.215
                                                                                            ^0.3)                                                                              3.7)
  Sorghum....             4          ^1.3   (^6.2, 3.8)         0.603           1.6   (^5.8, 9.7)         0.674           0.0   (^4.9, 5.2)         0.993         12.8      (^15.8,        0.418
                                                                                                                                                                              51.1)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
* `Number of pairs' refers to the number of comparisons in which replicates of a particular cultivar grown at a specific site under one set of growing conditions in 1 year at elevated [CO2]
  have been pooled and mean nutrient values for these replicates were compared with mean values for identical cultivars under identical growing conditions except grown at ambient [CO2]. In
  most instances, data from four replicates were pooled for each value, meaning that eight experiments were combined for each comparison (see Table 1 for details of experiments).


                                          Extended Data Table 2 D Original data combined with previously published FACE data from studies 3, 4, 6 and 7
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                     Zn (mg/g)                                 Fe (mg/g)                              Protein (mg/g)
                                                        N * (number ----------------------------------------------------------------------------------------------------------------------------
                                                         of pairs)         %          95% CI        P-value          %          95% CI        P-value          %          95% CI       P-value
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
C3 grasses
  Wheat..............................................            70          ^8.8       (^11.9,        <.0001          ^5.5  (^6.8, ^4.1)        <.0001          ^6.5  (^7.5, ^5.4)       <.0001
                                                                                          ^5.6)
  Rice...............................................            32          ^3.1  (^4.8, ^1.5)        <.0001          ^4.9  (^7.3, ^2.6)        <.0001            ^8  (^9.0, ^6.9)       <.0001
  Barley.............................................             4         ^11.4       (^19.3,         0.012         ^10.5       (^12.2,        <.0001         ^11.9       (^13.1,       <.0001
                                                                                          ^2.7)                                     ^8.7)                                    ^10.7)
C3 legumes
  Field peas.........................................            10          ^6.8  (^9.8, ^3.8)         0.002          ^4.1  (^6.7, ^1.4)         0.003          ^2.1  (^4.0, ^0.1)        0.039
  Soybeans...........................................            25          ^5.1  (^6.4, ^3.9)        <.0001          ^4.1  (^5.8, ^2.5)        <.0001           0.5   (^0.4, 1.3)        0.267
C3 tubers
  Potato.............................................             2          ^3.9  (^12.9, 6.2)         0.440           2.3   (^3.8, 8.7)         0.472          ^4.6  (^7.7, ^1.4)       <.0001
C4 grasses
  Maize..............................................             4          ^5.2  (^10.7, 0.6)         0.077          ^5.8       (^10.9,         0.038          ^4.6  (^13.0, 4.5)        0.312
                                                                                                                                    ^0.3)
  Sorghum............................................             4          ^1.3   (^6.2, 3.8)         0.603           1.6   (^5.8, 9.7)         0.674           0.0   (^4.9, 5.2)        0.993
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
See Extended Data Table 6 for a list of experiments. Percentage change in nutrient content at elevated [CO2] relative to ambient [CO2].
* `Number of pairs' refers to the number of comparisons in which replicates of a particular cultivar grown at a specific site under one set of growing conditions in 1 year at elevated [CO2]
  have been pooled and mean nutrient values for these replicates were compared with mean values for identical cultivars under identical growing conditions except grown at ambient [CO2]. In
  most instances, data from four replicates were pooled for each value, meaning that eight experiments were combined for each comparison (see Table 1 for details of experiments).


                                        Extended Data Table 3 D Original data combined with previously published FACE and chamber data from studies 1-10
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                     Zn (mg/g)                                 Fe (mg/g)                              Protein (mg/g)
                                                        N * (number ----------------------------------------------------------------------------------------------------------------------------
                                                         of pairs)         %          95% CI        P-value          %          95% CI        P-value          %          95% CI       P-value
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
C3 grasses
  Wheat..............................................            78          ^9.1       (^12.1,        <.0001          ^5.9  (^7.8, ^4.0)        <.0001          ^7.2   (^8.6,^5.8)       <.0001
                                                                                          ^6.1)
  Rice...............................................            32          ^3.1  (^4.8, ^1.5)        <.0001          ^4.9  (^7.3, ^2.6)        <.0001            ^8  (^9.0, ^6.9)       <.0001
  Barley.............................................             6         ^13.6       (^19.3,        <.0001         ^10.0       (^12.4,        <.0001         ^15.0       (^19.1,       <.0001
                                                                                          ^7.6)                                     ^7.4)                                    ^10.7)
C3 legumes
  Field peas.........................................            10          ^6.8  (^9.8, ^3.8)        <.0001          ^4.1  (^6.7, ^1.4)         0.003          ^2.1  (^4.0, ^0.1)        0.039
  Soybeans...........................................            28          ^5.0  (^6.1, ^3.9)        <.0001          ^5.2  (^7.9, ^2.5)        <.0001           0.1   (^0.8, 0.9)        0.865
C3 tubers
  Potato.............................................             5         ^10.0  (^20.9, 2.4)         0.110          ^4.1       (^16.6,         0.555          ^9.7       (^15.9,        0.005
                                                                                                                                    10.3)                                     ^3.1)
C4 grasses
  Maize..............................................             4          ^5.2  (^10.7, 0.6)         0.077          ^5.8       (^10.9,         0.038          ^4.6  (^13.0, 4.5)        0.312
                                                                                                                                    ^0.3)
  Sorghum............................................             7          ^0.6   (^4.5, 3.4)         0.764          33.8       (^10.2,         0.153          ^5.6  (^12.7, 2.1)        0.150
                                                                                                                                    99.3)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
See Extended Data Table 6 for a list of experiments. Percentage change in nutrient content at elevated [CO2] relative to ambient [CO2].
* `Number of pairs' refers to the number of comparisons in which replicates of a particular cultivar grown at a specific site under one set of growing conditions in 1 year at elevated [CO2]
  have been pooled and mean nutrient values for these replicates were compared with mean values for identical cultivars under identical growing conditions except grown at ambient [CO2]. In
  most instances, data from four replicates were pooled for each value, meaning that eight experiments were combined for each comparison (see Table 1 for details of experiments).


                                                     Extended Data Table 4 D Percentage change in nutrient content at elevated [CO2K] compared with ambient [CO2K] for all nutrients
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                C3 grasses                                                              C3 legumes                                                              C4 grasses
                 -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                 Wheat                               Rice                             Field Peas                            Soybean                              Maize                              Sorghum
                 -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                      %         95% CI      P-value       %         95% CI      P-value       %         95% CI      P-value       %         95% CI      P-value       %         95% CI      P-value       %         95% CI      P-value
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
     Zinc (ppm)        ^9.3       (^12.7,     <.0001       ^3.3  (^5.0, ^1.7)     <.0001       ^6.8  (^9.8, ^3.8)     <.0001       ^5.1  (^6.4, ^3.9)     <.0001       ^5.2  (^10.7, 0.6)      0.077       ^1.3   (^6.2, 3.8)      0.603
                                    ^5.9)
     Iron (ppm)        ^5.1  (^6.5, ^3.7)     <.0001       ^5.2  (^7.6, ^2.9)     <.0001       ^4.1  (^6.7, ^1.4)     <.0001       ^4.1  (^5.8, ^2.5)     <.0001       ^5.8       (^10.9,      0.038        1.6   (^5.8, 9.7)      0.674
                                                                                                                                                                                    ^0.3)
 Phytate (mg/g)        ^4.2  (^7.5, ^0.8)      0.009        1.2   (^4.6, 7.4)        0.7       ^5.8  (^11.5, 0.1)      0.055       ^1.3   (^3.7, 1.2)      0.303       ^6.1  (^15.0, 3.7)      0.215       12.8       (^15.8,      0.418
                                                                                                                                                                                                                        51.1)
        Protein        ^6.3  (^7.5, ^5.2)     <.0001       ^7.8  (^8.9, ^6.8)     <.0001       ^2.1  (^4.0, ^0.1)      0.039        0.5   (^0.4, 1.3)      0.267       ^4.6  (^13.0, 4.5)      0.312        0.0   (^4.9, 5.2)      0.993
       Mn (ppm)                                            ^7.5       (^12.0,     <.0001       ^2.5  (^4.2, ^0.8)      0.005       ^1.4   (^3.5, 0.8)      0.204       ^4.2  (^10.5, 2.5)      0.215        1.7   (^4.5, 8.3)      0.596
                                                                        ^2.8)
         Mg (%)                                            ^0.9   (^2.3, 0.6)       0.24        0.0   (^1.3, 1.4)      0.960       ^3.5  (^4.3, ^2.8)     <.0001       ^5.7  (^9.9, ^1.3)      0.011       ^0.2   (^5.1, 4.9)      0.944
       Cu (ppm)                                           ^10.6       (^13.8,     <.0001       ^2.7  (^5.1, ^0.3)      0.025       ^5.7  (^8.0, ^3.4)     <.0001       ^9.9  (^19.3, 0.7)      0.066       ^2.9   (^7.1, 1.5)      0.190
                                                                        ^7.1)
         Ca (%)                                               2   (^0.8, 4.9)       0.16       ^0.5   (^4.2, 3.3)      0.787       ^5.8  (^7.3, ^4.2)     <.0001       ^2.7       (^16.9,      0.734       11.2  (^5.2, 30.3)      0.190
                                                                                                                                                                                    13.9)
        S (ppm)                                            ^7.8  (^8.8, ^6.8)     <.0001       ^2.2  (^3.6, ^0.7)      0.003       ^2.9  (^3.5, ^2.2)     <.0001        2.1   (^2.2, 6.7)      0.342       ^0.2   (^5.4, 5.2)      0.936
          K (%)                                             1.1   (^0.3, 2.5)       0.13        2.2    (0.6, 3.8)      0.008        0.1   (^0.8, 1.0)      0.857       ^2.7  (^3.1, ^2.2)     <.0001        3.0   (^2.7, 9.1)      0.308
        B (ppm)                                             5.1    (1.9, 8.4)      0.002       ^1.9   (^3.9, 0.1)      0.057       ^6.4  (^9.1, ^3.6)     <.0001        4.9  (^1.0, 11.1)      0.107       ^0.3   (^9.3, 9.6)      0.952
          P (%)                                            ^1.0   (^2.4, 0.4)      0.160       ^3.7  (^6.8, ^0.5)      0.023       ^0.7   (^2.2, 0.9)      0.379       ^7.1  (^9.0, ^5.1)     <.0001        0.3   (^4.0, 4.9)      0.881
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sample sizes for each crop type are identical to those listed in Table 1.


Extended Data Table 5 D Countries whose populations receive at least 60%
         of dietary iron and/or zinc from C3 grains and legumes
------------------------------------------------------------------------
                         % Iron from C3   % Zinc from C3
        Country             grains &         grains &       Population
                            legumes          legumes      (in thousands)
------------------------------------------------------------------------
        Afghanistan               78%              78%           31,412
            Algeria               76%              79%           35,468
               Iraq               74%              83%           31,672
         Bangladesh               72%              88%          148,692
Iran, Islamic Rep. of             72%              77%           73,974
           Pakistan               70%              72%          173,593
            Tunisia               70%              77%           10,481
             Jordan               69%              73%            6,187
            Morocco               69%              78%           31,951
Syrian Arab Republic              67%              71%           20,411
                   Libya          67%              71%            6,355
              Yemen               66%              75%           24,053
            Myanmar               65%              81%           47,963
         Tajikistan               62%              56%            6,879
              India               59%              71%        1,224,614
              Egypt               54%              65%           81,121
          Indonesia               52%              65%          239,871
            Sierra Leone          51%              70%            5,868
           Cambodia               49%              68%           14,138
               Sri Lanka          46%              69%           20,860
                   Laos           44%              66%            6,201
           Viet Nam               43%              61%           87,848
                                                         ---------------
  Total...............                                        2,329,612
------------------------------------------------------------------------
Source: United Nations Food and Agriculture Organization food balance
  sheets and 2010 United Nations estimated population.


  Extended Data Table 6 D Literature reporting nutrient changes in the
       edible portion of crops grown at elevated and ambient [CO2]
------------------------------------------------------------------------
 Study        Experimental Method             Associated Citations
------------------------------------------------------------------------
     1   Growth Chambers                Conroy, J., Seneweera, S.P.,
                                         Basra, A., Rogers, G. & Nissen-
                                         Wooller, B. Influence of rising
                                         atmospheric CO2 concentrations
                                         and temperature on growth,
                                         yield and grain quality of
                                         cereal crops. Australian
                                         Journal of Plant Physiology 21,
                                         741-758 (1994).
                                        Seneweera, S., Milham, P. &
                                         Conroy, J. Influence of
                                         elevated CO2 and phosphorus
                                         nutrition on the growth and
                                         yield of a short-duration rice.
                                         Australian Journal of Plant
                                         Physiology 21, 281-292 (1994).
                                        Seneweera, S.P. & Conroy, J.P.
                                         Growth, grain yield and quality
                                         of rice (Oryza sativa L.) in
                                         response to elevated CO2 and
                                         phosphorus nutrition (Reprinted
                                         from Plant nutrition for
                                         sustainable food production and
                                         environment, 1997). Soil Sci.
                                         Plant Nutr. 43, 1131-1136
                                         (1997).
     2   Temperature Gradient Tunnels   De la Puente, L.S., Perez, P.P.,
                                         Martinez-Carrasco, R.,
                                         Morcuende, R.M. & Del Molino,
                                         I.M.M. Action of elevated CO2
                                         and high temperatures on the
                                         mineral chemical composition of
                                         two varieties of wheat.
                                         Agrochimica 44, 221-230 (2000).
     3   Open Top Chambers & FACE       De Temmerman L., et al. Effect
                                         of climatic conditions on tuber
                                         yield (Solanum tuberosum L.) in
                                         the European `CHIP'
                                         experiments. European Journal
                                         of Agronomy 17, 243-255 (2002).
                                        De Temmerman, L., Hacour, A. &
                                         Guns, M. Changing climate and
                                         potential impacts on potato
                                         yields and quality `CHIP':
                                         introduction, aims and
                                         methodology. European Journal
                                         of Agronomy 17, 233-242 (2002).
                                        Fangmeier, A., De Temmerman, L.,
                                         Black, C., Persson, K. & Vorne,
                                         V. Effects of elevated CO2 and/
                                         or ozone on nutrient
                                         concentrations and nutrient
                                         uptake of potatoes. European
                                         Journal of Agronomy 17, 353-368
                                         (2002).
                                        Hogy, P. & Fangmeier, A.
                                         Atmospheric CO2 enrichment
                                         affects potatoes: 2. Tuber
                                         quality traits. European
                                         Journal of Agronomy 30, 85-94
                                         (2009).
     4   FACE                           Erbs, M., et al. Effects of free-
                                         air CO2 enrichment and nitrogen
                                         supply on grain quality
                                         parameters and elemental
                                         composition of wheat and barley
                                         grown in a crop rotation.
                                         Agriculture, Ecosystems and
                                         Environment 136, 59-68 (2010).
     5   Open Top Chambers              Fangmeier, A., et al. Effects of
                                         elevated CO2, nitrogen supply
                                         and tropospheric ozone on
                                         spring wheat. I. Growth and
                                         yield. Environmental Pollution
                                         91, 381-390 (1996).
                                        Fangmeier, A., Gruters, U.,
                                         Hogy, P., Vermehren, B. &
                                         Jager, H.-J. Effects of
                                         elevated CO2, nitrogen supply
                                         and tropospheric ozone on
                                         spring wheat--II. Nutrients (N,
                                         P, K, S, Ca, Mg, Fe, Mn, Zn).
                                         Environmental Pollution 96, 43-
                                         59 (1997).
                                        Fangmeier, A., et al. Effects on
                                         nutrients and on grain quality
                                         in spring wheat crops grown
                                         under elevated CO2
                                         concentrations and stress
                                         conditions in the European,
                                         multiple-site experiment
                                         'ESPACE-wheat'. European
                                         Journal of Agronomy 10, 215-229
                                         (1999).
                                        Jager, H.-J., Hertstein, U. &
                                         Fangmeier, A. The European
                                         Stress Physiology and Climate
                                         Experiment--project 1: wheat
                                         (ESPACE-wheat): introduction,
                                         aims and methodology. European
                                         Journal of Agronomy 10, 155-162
                                         (1999).
     6   FACE                           Hogy, P. & Fangmeier, A. Effects
                                         of elevated atmospheric CO2 on
                                         grain quality of wheat. Journal
                                         of Cereal Science 48, 580-591
                                         (2008).
                                        Hogy, P., et al. Does elevated
                                         atmospheric CO2 allow for
                                         sufficient wheat grain quality
                                         in the future?. Journal of
                                         Applied Botany and Food Quality
                                         82, 114-121 (2009).
                                        Hogy, P., et al. Effects of
                                         elevated CO2 on grain yield and
                                         quality of wheat: results from
                                         a 3-year free-air CO2
                                         enrichment experiment. Plant
                                         Biology 11, 60-69 (2009).
                                        Hogy, P., Zorb, C.,
                                         Langenkamper, G., Betsche, T. &
                                         Fangmeier, A. Atmospheric CO2
                                         enrichment changes the wheat
                                         grain proteome. Journal of
                                         Cereal Science 50, 248-254
                                         (2009).
     7   FACE                           Kim , H., Lieffering, M., Miura,
                                         S., Kobayashi, K. & Okada, M.
                                         Growth and nitrogen uptake of
                                         CO2-enriched rice under field
                                         conditions. New Phytologist
                                         150, 223-229 (2001).
                                        Kim, H., et al. Effects of free-
                                         air CO2 enrichment and nitrogen
                                         supply on the yield of
                                         temperate paddy rice crops.
                                         Field Crops Research 83, 261-
                                         270 (2003).
                                        Lieffering, M., Kim, H.-Y.,
                                         Kobayashi, K. & Okada, M. The
                                         impact of elevated CO2 on the
                                         elemental concentrations of
                                         field-grown rice grains. Field
                                         Crops Research 88, 279-286
                                         (2004).
     8   Open Top Chambers              Pleijel, H., et al. Effects of
                                         elevated carbon dioxide, ozone
                                         and water availability on
                                         spring wheat growth and yield.
                                         Physiologia Plantarum 108, 61-
                                         70 (2000).
                                        Pleijel, H. & Danielsson, H.
                                         Yield dilution of grain Zn in
                                         wheat grown in open-top chamber
                                         experiments with elevated CO2
                                         and O3 exposure. Journal of
                                         Cereal Science 50, 278-282
                                         (2009).
     9   Open Top Chambers              Prior, S.A., Runion, G.B.,
                                         Rogers, H.H., Torbert, H.A.
                                         Effects of atmospheric CO2
                                         enrichment on crop nutrient
                                         dynamics under no-till
                                         conditions. Journal of Plant
                                         Nutrition 31, 758-773 (2008).
    10   Open Top Chambers              Weigel, H., Manderscheid, R.,
                                         Jager, H.-J. & Mejer, G.
                                         Effects of season-long CO2
                                         enrichment on cereals. I.
                                         Growth performance and yield.
                                         Agriculture, Ecosystems and
                                         Environment 48, 231-240 (1994).
                                        Manderscheid, R., Bender, J.,
                                         Jager, H.-J. & Weigel, H.J.
                                         Effects of season long CO2
                                         enrichment on cereals. II.
                                         Nutrient concentrations and
                                         grain quality. Agriculture,
                                         Ecosystems & Environment 54,
                                         175-185 (1995).
    11   FACE                           Yang, L., Wang, Y., Dong, G.,
                                         Gu, H., Huang, J., Zhu, J.,
                                         Yang, H., Liu, G., Han, Y. The
                                         impact of free-air CO2
                                         enrichment (FACE) and nitrogen
                                         supply on grain quality of
                                         rice. Field Crops Research 102,
                                         128-140 (2007).
         Meta-Analyses                  Loladze, I. Rising atmospheric
                                         CO2 and human nutrition: toward
                                         globally imbalanced plant
                                         stoichiometry? Trends in
                                         Ecology and Evolution 17 (10),
                                         457-461 (2002). [Uses data from
                                         studies 1, 2, 5, and 10 as well
                                         as numerous other studies on
                                         non-edible tissues and plants
                                         other than food crops].
                                        McGrath, J.M. and Lobell, D.B.
                                         Reduction of transpiration and
                                         altered nutrient allocation
                                         contribute to nutrient decline
                                         of crops grown in elevated CO2
                                         concentrations. lant, Cell, &
                                         Environment 36, 697-705 (2013).
                                         [Uses data from studies 1, 5,
                                         and 10 as well as numerous
                                         other studies on non-edible
                                         tissues and plants other than
                                         food crops].
                                        Duval, B.D., Blankinship, J. C.,
                                         Dijkstra, P., Hungate, B. A.
                                         CO2 effects on plant nutrient
                                         concentration depend on plant
                                         functional group and available
                                         nitrogen: a meta-analysis.
                                         Plant Ecology 213, 505-521
                                         (2012). [Uses data from studies
                                         1, 2, 3, 5, 6, and 9 as well as
                                         numerous other studies on non-
                                         edible tissues and plants other
                                         than food crops].
------------------------------------------------------------------------

                               Article 4
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

[https://www.nature.com/articles/s41467-020-20678-z]
Nature
Communications
Over half of western United States' most abundant tree species in 
        decline
Hunter Stanke,1, 2, * Andrew O. Finley,1, 3 Grant 
M. Domke,\4\ Aaron S. Weed \5\ & David W. MacFarlane \1\
---------------------------------------------------------------------------
    \1\ Department of Forestry, Michigan State University, East 
Lansing, MI, USA.
    \2\ School of Environmental and Forest Sciences, University of 
Washington, Seattle, WA, USA.
    \3\ Department of Geography, Environment, and Spatial Sciences, 
Michigan State University, East Lansing, MI, USA.
    \4\ Forest Service, Northern Research Station, U.S. Department of 
Agriculture, St. Paul, MN, USA.
    \5\ Northeast Temperate Inventory and Monitoring Network, U.S. 
National Park Service, Woodstock, VT, USA.
    * email: [email protected].
---------------------------------------------------------------------------
Abstract
    Changing forest disturbance regimes and climate are driving 
accelerated tree mortality across temperate forests. However, it 
remains unknown if elevated mortality has induced decline of tree 
populations and the ecological, economic, and social benefits they 
provide. Here, we develop a standardized forest demographic index and 
use it to quantify trends in tree population dynamics over the last 2 
decades in the western United States. The rate and pattern of change we 
observe across species and tree size-distributions is alarming and 
often undesirable. We observe significant population decline in a 
majority of species examined, show decline was particularly severe, 
albeit size-dependent, among subalpine tree species, and provide 
evidence of widespread shifts in the size-structure of montane forests. 
Our findings offer a stark warning of changing forest composition and 
structure across the western U.S., and suggest that sustained 
anthropogenic and natural stress will likely result in broad-scale 
transformation of temperate forests globally.
Introduction
    Persistent shifts in forest composition, structure, and function 
depend largely on the demographic response of trees to changing 
environmental drivers and disturbance regimes.1, 2 Across 
temperate forests--representing 25% of the world's forested land area 
\3\--recent reports of increasing tree mortality have been attributed 
to complex interactions among climate, native insects and pathogens, 
and uncharacteristically severe wildfire.4, 5, 6 Such 
pervasive changes in tree population dynamics can have substantial 
impacts on the ecosystem services provided by temperate forests, 
including carbon storage and sequestration,\7\ climate regulation,\8\ 
and provisioning of drinking water.\9\ Sustained anthropogenic and 
natural stress is thus expected to result in broad-scale transformation 
of temperate forests and the services they provide.10, 11 As 
such, a key challenge for ecological research is to quantify the 
patterns and underlying drivers of changing tree populations to better 
inform forest management and help ease ecological transitions.\12\
    Tree demographic rates (e.g., mortality) are important, widely used 
indicators of forest health.\12\ However, tree demographic rates are 
confounded by stand development processes (i.e., stand aging) 
13, 14 and do not yield a comprehensive depiction of tree 
population dynamics when considered individually (i.e., the net result 
of growth, recruitment, and mortality processes; tree abundance 
shifts).15, 16, 17 Thus, while recent reports of elevated 
tree mortality are suggestive of broad-scale changes in the composition 
and structure of temperate forests,4, 5, 18 such conclusions 
should not be accepted in the absence of information regarding tree 
recruitment, growth, and stand development.1, 19 Previous 
efforts to quantify trends in tree population dynamics have often 
relied on observations from old forests to minimize the influence of 
stand development processes.5, 18 Still, patterns of tree 
population dynamics observed in old forests are seldom characteristic 
of those in younger forests \20\ and are thus unlikely to be 
representative of patterns emerging across forest landscapes (or 
forested regions) that are composed of a mosaic of stands in various 
stages of development.\21\ As such, advancement in detection and 
prediction of forest health decline depends largely on the 
dissemination of methods that comprehensively describe tree population 
dynamics and account for variation in tree demography arising from 
stand development processes.14, 19
    To this end, we propose the forest stability index (FSI), a direct 
measure of temporal change in relative live tree density that is 
independent of stand development processes by design. Temporal change 
in absolute tree density (e.g., trees per hectare (TPH)) emerges from 
the joint demographic response of tree populations to endogenous (e.g., 
inter-tree competition) and exogenous drivers (e.g., wildfire).\22\ 
That is, change in absolute tree density is the net result of 
mortality, growth, and recruitment processes, and is thus a 
demographically comprehensive measure of tree population dynamics. 
Relative tree density may be defined as the proportion of absolute tree 
density observed in a stand relative to the maximum theoretical density 
the stand could achieve given its observed tree size-distribution. The 
maximum density that a population of trees may achieve is expected to 
decline as individuals grow in size, following well-established 
allometric scaling laws that drive stand development processes (i.e., 
self-thinning).15, 16, 17, 23, 24 Indices of relative tree 
density (i.e., ratio of observed and maximum theoretical tree density) 
are thus independent of stand development processes by definition, as 
allometric tree size-density relationships are explicitly acknowledged 
in their denominator.
    The FSI is defined as the change in relative density observed in a 
population of trees over time (e.g., via remeasurement of forest 
inventory plots). Here stability is achieved when the relative density 
of a tree population is constant (e.g., FSI equal to zero, stand 
remains at 50% stocking over time), despite underlying changes in 
absolute tree density and size distribution. Stability in this sense is 
uncommon at the stand-scale, as stands progress toward maximum relative 
density in the absence of exogenous stress (positive FSI, e.g., tree 
growth exceeds mortality) and relative density is expected to decline 
given disturbance (negative FSI, e.g., disturbances act as thinning 
agents). At the landscape-scale, however, stability represents a 
balance between disturbance and tree growth processes, and deviations 
from this dynamic equilibrium may be indicative of pervasive changes in 
forest structure, composition, and function.
    We use the FSI to identify patterns in relative tree density shifts 
of the eight most abundant tree species in the western United States 
(U.S.) and determine the importance of major forest disturbances in 
driving the population dynamics of each species over the last 2 
decades. Many forests in the western U.S. have experienced recent 
increases in the extent, severity, and frequency of 
wildfire,25, 26 drought,27, 28 and insect-pest 
outbreaks,29, 30 owing in part to changing climate and past 
forest management (i.e., fire suppression). Likewise, large-scale tree 
mortality events 5, 31 and recruitment failures 
32, 33 indicate that widespread forest change is already 
underway in the region. Such issues are not, however, unique to forests 
of the western U.S. Increased disturbance activity has been documented 
in other regions of the temperate biome in recent 
decades,12, 34, 35 and the broad spatial and climatic domain 
encompassed by the western U.S. suggests that patterns of forest change 
observed herein may be highly relevant to temperate forests across the 
globe.
    We draw upon over 24,000 repeated censuses of U.S. Forest Service 
Forest Inventory and Analysis (FIA) plots to address the following 
questions: (1) What is the current status of populations of the eight 
most abundant tree species in the western U.S. (i.e., expanding, 
declining), and what do inter-specific differences in the rate of 
relative tree density shifts indicate about changes in forest 
composition? (2) Is the rate of relative tree density shifts size-
dependent, and if so, what do these relationships indicate about 
changes in forest structure? (3) Does the rate of relative tree density 
shifts vary across space within species ranges, and what are the 
general patterns of change for each species? (4) How do major forest 
disturbances influence the populations of these dominant species, and 
what do these relationships suggest about species sensitivity to future 
changes in forest disturbance regimes?
    Here, we show a majority of the most abundant tree species in the 
western U.S. experienced significant population decline over the last 2 
decades. Further, we show the magnitude of change in tree populations 
diverges strongly across species, species-size distributions, and 
species ranges, and the patterns of such change are generally 
inconsistent with broad-scale reversion of forests toward historical 
conditions. Altogether, we provide empirical evidence of widespread, 
yet spatially varying, changes in forest composition and structure over 
the last 2 decades in the western U.S.
Results
    We identified the eight most abundant tree species in the western 
U.S. by their estimated total number of live stems (i.e., diameter 
%2.54 cm at 1.37 m above ground) across the region (Fig. 1). Top 
species represented six distinct genera and three families (Table 1). 
We categorized species by general ecosystem associations, including two 
woodland species (i.e., characteristic of mid-high-elevation desert/
steppe), three subalpine species (i.e., commonly occurring in cool, 
moist high-elevation forests), and three montane species (i.e., 
characteristic of mid-elevation forests climatically bounded by 
woodland (hotter, drier) and subalpine ecosystems (cooler, wetter)). 
Together these top eight species accounted for 61.6% of all live trees 
across the study region (62.3% of total live basal area).
Fig. 1: Study area colored by ecoregion divisions
[GRAPHIC NOT AVAILABLE IN TIFF FORMAT]

          Ecoregion divisions are differentiated by broad-scale 
        patterns of precipitation and temperature. Our study area spans 
        both the humid and dry domains of the western U.S. We exclude 
        the state of Wyoming due a lack of data.

                                 Table 1
------------------------------------------------------------------------
               Scientific       Ecosystem                          No.
Common name       name         association        Prevalence      plots
------------------------------------------------------------------------
Douglas-fir  Pseudotsuga     Montane                       0.15   12,284
              menziesii
              Mirb.
Lodgepole    Pinus contorta  Subalpine                     0.11     4556
 pine         Doug.
Subalpine    Abies           Subalpine                     0.09     3174
 fir          lasiocarpa
              Hook.
Ponderosa    Pinus           Montane                       0.06     7309
 pine         ponderosa
              Doug.
Common       Pinus edulis    Woodland                      0.05     3076
 pinyon       Engelm.
Quaking      Populus         Montane                       0.05     1723
 aspen        tremuloides
              Michx.
Engelmann    Picea           Subalpine                     0.05     3079
 spruce       Engelmannii
              Parry
Utah         Juniperus       Woodland                      0.04     3446
 juniper      osteosperma
              Torr.
------------------------------------------------------------------------
Scientific and common names of the eight most abundant tree species
  across the western U.S., listed in order of decreasing prevalence
  (i.e., the proportion of total number of stems represented by each
  species across the region).
Commonly accepted ecosystem associations are reported for each species
  along with their respective sample size in the FIA plot network
  (remeasured plots only).

    The FSI is defined as the average annual change in the relative 
density of a population of live trees, or the ratio of observed tree 
density to maximum potential tree density given site conditions and 
observed tree size-distributions. Hence, significant positive values of 
the FSI indicate increased relative density (i.e., population 
expansion), significant negative values indicate decreased relative 
density (i.e., population decline), and values of the FSI not 
significantly different from zero indicate population stability (i.e., 
no change in relative density). Herein, we treat changes in population 
range boundaries and within-range density shifts as functionally 
equivalent processes. For example, range expansion (population 
occurrence on a site where it was previously absent) is represented by 
the FSI as a positive change in relative density (i.e., where previous 
relative density is zero). Thus, when summarized across broad spatial 
domains the FSI represents a comprehensive measure of the net 
performance of a population of trees during the temporal frame of 
sampling (i.e., in terms of net changes in relative abundance).
Broad-scale shifts in forest composition and structure
    Species-level estimates of the mean FSI across the entire study 
region (i.e., range-average estimates) reveal broad-scale patterns of 
rapid change in the composition of western U.S. forests (over 91 
million hectares of forestland) over the last 2 decades (Fig. 2). Three 
of the eight most abundant species in the region (lodgepole pine, 
Engelmann spruce, and quaking aspen) exhibited average decreases in 
relative density (i.e., population decline) at rates exceeding 1% per 
year over the 18 year study period (2001-2018), whereas Douglas-fir 
increased in relative density at nearly the same rate. For reference, a 
%FSI equal to 1% is equivalent to an 18% change in relative density 
over the duration of the study period. Across all species, population 
decline occurred more frequently (five of eight of species) and with 
greater magnitude (Fig. 2; leftward skew) than population expansion.
Fig. 2: Range-average % forest stability index (FSI) of the eight most 
        abundant tree species in the western U.S. over the period 2001-
        2018
        [GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
        
          Population decline (red) occurs when the FSI is negative and 
        the associated 95% confidence interval does not include zero. 
        Conversely, population expansion (blue) occurs when the FSI is 
        positive and the associated confidence interval does not 
        include zero. Here, the %FSI is a direct measure of average 
        annual percent change in the relative density of each species 
        across their ranges in the western U.S. Thus, total % change in 
        relative density can be estimated by multiplying the %FSI by 
        the length of the study period (18 years). For reference, 
        complete loss of a species over the study period would be 
        indicated by a %FSI value of ^5.56%. Source data are provided 
        as a Source Data file.

    Severe rates of population decline were apparent in all three 
subalpine species considered herein, with lodgepole pine and Engelmann 
spruce exhibiting the highest rates of decline among all species 
(lodgepole pine approaching decline of 2% annually, 36% over the entire 
study period). Douglas-fir and ponderosa pine, both montane species, 
exhibited the highest rates of range-wide population expansion. In 
contrast, quaking aspen populations declined at a rate exceeding the 
rate of expansion observed in other montane species. Woodland species 
exhibited the highest degree of population stability (range-average 
mean FSI values closest to zero) over the last 2 decades, although low 
rates (<0.20% annually, 3.6% over the duration of the study period) of 
population expansion and decline were observed for Utah juniper and 
common pinyon, respectively.
    Variation in range-average estimates of the FSI across species-size 
distributions are indicative of extensive, complex shifts in the size-
structure of forests of the western U.S. over the period 2001-2018 
(Fig. 3). Rapid population decline was evident in nearly all size-
classes of subalpine tree species (except the smallest 10% of subalpine 
fir and lodgepole pine). Further, the rate of population decline 
appeared to increase with increasing tree size across all subalpine 
species (Fig. 3; downward trend in FSI), and this trend was most severe 
in lodgepole pine (largest 20% of trees declined at rates exceeding 3% 
annually, 54% over the duration of the study period). The opposite 
pattern appeared for Douglas-fir and ponderosa pine, where the largest 
trees generally outperformed the smallest trees of each species (i.e., 
higher or more positive changes in relative density).
Fig. 3: Range-average % forest stability index (FSI) across size 
        distributions of the eight most abundant tree species in the 
        western U.S. over the period 2001-2018
        [GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
        
          Population decline (red) occurs when the FSI is negative and 
        the associated confidence interval does not include zero. 
        Conversely, population expansion (blue) occurs when the FSI is 
        positive and the associated confidence interval does not 
        include zero. Here, the %FSI is a direct measure of average 
        annual percent change in the relative density of each species 
        across their ranges in the western U.S., and variation in the 
        FSI across species-size distributions is indicative of shifts 
        in forest structure during the study period. Total % change in 
        relative density can be estimated by multiplying the %FSI by 
        the length of the study period (18 years), with a maximum 
        annual decline of ^5.56% (complete loss of the population over 
        the study period). Source data are provided as a Source Data 
        file.

    Interestingly, population decline was evident among the smallest 
size-classes of Douglas-fir (lower 20%) and ponderosa pine (lower 50%), 
whereas the largest size-classes of both species exhibited population 
expansion. Patterns of change in relative density across the size-
distribution of quaking aspen appeared to follow an approximately 
quadratic trend, with population expansion evident in the smallest and 
largest 10% of stems and severe population decline (approaching 3% 
annually, 54% over the duration of the study period) apparent near the 
median (50%) tree size class. The size distribution of woodland species 
(i.e., common pinyon and Utah juniper) appeared to be the most stable 
of all species examined, indicated by relatively low variation in 
relative density shifts across tree size-classes (Fig. 3; nearly flat 
trends).
Early indications of shifting species distributions
    Summaries of the FSI within ecoregion divisions revealed broad-
scale spatial patterns of change in the relative density of each 
species over the last 2 decades in the western U.S. (Fig. 4b). 
Population decline was spatially pervasive among all subalpine species 
and particularly severe for lodgepole pine in the mountain temperate 
steppe division (i.e., central and northern Rocky Mountains). Though 
interestingly, lodgepole pine populations increased in relative density 
(i.e., population expansion) in the mountain marine (i.e., coastal 
Pacific Northwest) and mountain Mediterranean (i.e., Sierra Nevada) 
divisions over the study period. Quaking aspen exhibited consistent 
rates of population decline across its range within the study region 
(1% annually, 18% over the duration of the study period). Spatial 
patterns of relative density shifts of Douglas-fir and ponderosa pine 
were similar, with decline evident for both species in the mountain 
subtropical steppe division (i.e., southern Rocky Mountains) and 
expansion in the northwestern portion of the study region (particularly 
strong for Douglas-fir in the marine and mountain marine divisions). In 
contrast, we found general patterns of population stability across the 
ranges of both woodland species, with the majority of each species' 
range characterized by FSI values near zero.
Fig. 4: Spatial variation in the % forest stability index (%FSI) of 
        eight most abundant species across their ranges in the western 
        U.S. over the period 2001-2018
        [GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
        
          Mean %FSI values are mapped at two spatial scales: ecoregion 
        subsection a and ecoregion division b. Boundaries of the study 
        region are outlined in black, and white areas within the study 
        area indicate absence of a species in the FIA plot network 
        (i.e., colored regions represent species' ranges). For 
        reference, ecoregion division boundaries (as seen in Fig. 1) 
        are outlined as gray dotted lines, and maps of the %FSI within 
        ecoregion divisions (bottom) have been clipped to the extent of 
        each species' range (i.e., defined by ecoregion subsections 
        where the species was detected on an FIA plot). Tree 
        populations have been observed to expand in areas characterized 
        by positive FSI estimates (blue), and decline in areas 
        characterized by negative %FSI estimates (red) during the 
        inventory period (approximately 2 decades). For reference, %FSI 
        values ^2% indicate a 36% decline in relative density over the 
        duration of the study period. Source data are provided as a 
        Source Data file.

    While the general spatial patterns of the FSI observed in 
subsection-level summaries (Fig. 4a) mirrored those of division-level 
summaries, subsection-level summaries revealed patterns of change in 
species relative density at finer spatial scales than division-level 
summaries. Qualitatively, the FSI appears to exhibit strong, positive 
spatial auto-correlation across ecoregion subsections, and such local-
scale variation is not well represented in division-level summaries. 
Specifically, local regions of population expansion and regions of 
population decline (i.e., consisting of multiple adjoining ecoregion 
subsections with similar FSI values) emerge to varying degrees within 
the range of each species. However, spatial patterns of population 
performance were not always consistent among overlapping species, 
indicating shifts in local-scale forest composition.
Forest disturbances as drivers of relative tree density shifts
    Estimated effects of forest disturbances on relative density 
highlight disturbances as important drivers of tree population dynamics 
in the western U.S., though the magnitude of disturbance effects varied 
strongly by tree species and disturbance type (Fig. 5). Here, we 
present effects of forest disturbances as percent change in relative 
tree density estimated to be caused by each disturbance type at the 
population-level (i.e., product of disturbance severity and disturbance 
probability). Hence, high magnitude of estimated effects indicates a 
disturbance type is an important driver of the population dynamics of a 
tree species (e.g., Fig. 5, insect outbreaks in lodgepole pine).
Fig. 5: Posterior distributions of the estimated effects of forest 
        disturbances on the relative density of live tree populations 
        for the eight most abundant species in the western U.S. over 
        the period 2001-2018
        [GRAPHIC NOT AVAILABLE IN TIFF FORMAT]
        
          Change in relative tree density resulting from each 
        disturbance type is estimated as the product of average 
        disturbance severity and probability (annual), where 
        disturbance severity is defined as the average difference in 
        relative density shifts between undisturbed and disturbed 
        sites. Posterior probability distributions of parameters are 
        estimated via Markov chain Monte Carlo (5,000 samples). 
        Posterior medians of each parameter are plotted as black 
        vertical lines. Asterisks indicate the 95% credible interval of 
        the mean effect excludes zero, and hence are considered 
        statistically significant. Source data are provided as a Source 
        Data file.

    Across all species, fire and insect outbreaks generally emerged as 
more important drivers (i.e., larger estimated effects) of relative 
density shifts than disease (Fig. 5), although the effects of disease 
exceeded those of fire and insects for quaking aspen. In most cases, 
disturbance was negatively associated with changes in relative density, 
however estimated effects of disease were positive in Engelmann spruce 
and lodgepole pine over the study period. Disturbance effects appeared 
to be most severe (i.e., highest magnitude, exceeding 0.2% annually) 
among subalpine species, where insect outbreaks were determined to be 
dominant drivers of relative density shifts in Engelmann spruce and 
lodgepole pine, and fire was of heightened importance for subalpine 
fir. Fire also emerged as the most important disturbance type affecting 
the relative density of Douglas-fir and ponderosa pine, both montane 
species. The effects of disturbance appeared to be least severe among 
Utah juniper and common pinyon, relative to other species (<0.1% 
annually).
Discussion
    Complex interactions between changing climate, forest disturbance 
regimes, and past forest management (e.g., fire suppression) are 
driving accelerated change in tree demography in temperate 
forests.4, 5, 36 However, a great deal of uncertainty 
remains regarding the net result of such demographic change and its 
consequences for forest composition and structure across broad spatial 
domains1. Herein, we develop the FSI, a standardized demographic index 
that weights observed changes in live tree density and tree size 
against those expected given well-established allometric size-density 
relationships in forests. We then apply the FSI to over 24,000 
remeasured forest inventory plots in the western U.S. to quantify 
recent trends in tree population dynamics in the region. Our results 
indicate a majority of the most abundant tree species in the western 
U.S. experienced significant population decline over the period 2001-
2018 (five of eight species, representing 60.7% of all stems of study 
species), where population decline is indicated by a net decrease in 
relative live tree density (i.e., negative FSI). Furthermore, we found 
strong divergence in the magnitude of change in relative tree density 
across species (Fig. 2), species-size distributions (Fig. 3), and 
species ranges (Fig. 4). Such dramatic variation in relative density 
shifts provides empirical evidence of broad-scale, yet spatially 
varying, changes in forest composition and structure over the last 2 
decades in the western U.S.
    Importantly, the current composition and structure of many forests 
types in the western U.S. differ drastically from their historic range 
of variability, arising as a legacy of widespread fire suppression 
(early 20th century to present day) and intensive harvesting (19th to 
early 20th century).\37\ Novel forest conditions (e.g., abundance of 
high density, closed-canopy forests dominated by fire-intolerant 
species) have interacted with changing climate to incite rapid 
increases in disturbance activity in the western U.S. and other regions 
of the temperate biome.29, 34 At face-value, it is therefore 
not inherently surprising to observe a net decrease in the relative 
density of many top tree species in the western U.S., as disturbances 
act as natural thinning agents in tree populations. However, the 
examination of patterns in live tree density shifts across species 
ranges and size-distributions offers a sobering line of evidence that 
is inconsistent with broad-scale reversion of forests toward historical 
conditions. Instead, our results support the following general trends 
in western U.S. forests over the last 2 decades: (1) severe, spatially 
pervasive decline of subalpine forests coinciding with density shifts 
towards smaller tree size-classes; (2) broad-scale expansion of large-
diameter montane conifers and decline of small-diameter conspecifics; 
and (3) net population stability of woodland species.
    The rate of population decline we observed in subalpine species is 
particularly severe (comprising 25.3% of all trees in the western 
U.S.). Over the duration of the 18 year study period, the relative 
density of lodgepole pine declined 32.2% (R0.05%) across its range in 
the western United States, while Engelmann spruce and subalpine fir 
declined 21.3% (R0.05%) and 13.2% (R0.04%) across their respective 
ranges, respectively (Fig. 2). Decline appears spatially pervasive at 
broad scales across the study region (ecoregion divisions), however 
local regions of intense population decline and expansion emerge at 
finer spatial scales (ecoregion subsections) for all subalpine species 
(Fig. 4). Such patterns may indicate the primary drivers of subalpine 
tree population dynamics operate at sub-regional scales, likely 
responding to local-scale variation in climate, topoedaphic conditions, 
and disturbance history.\37\ Previous studies have indicated that 
subalpine tree species are among the most vulnerable to future changes 
in climate and forest disturbance regimes.38, 39, 40 Our 
results indicate this heightened vulnerability is already manifesting 
across the western U.S., serving as an early warning of potentially 
widespread, rapid decline of subalpine forests in other regions of the 
temperate biome.
    Interestingly, we show that severity of population decline 
increased with tree size for each subalpine species during the study 
period (Fig. 3). That is, population decline was most severe among the 
largest trees of each species. This result adds to an increasing body 
of evidence, suggesting that large, old trees are at high risk of 
decline in forests across the globe.\41\ Large, old trees generally 
occur at low density but are of high ecological significance, 
influencing the rates and patterns of regeneration and succession, 
moderating microclimate and water use, and contributing 
disproportionately to forest biomass and carbon cycling at a global 
scale.\42\ Hence, the rapid decline of large-diameter trees we observe 
in subalpine tree species of the western U.S. is of grave concern and 
may foreshadow broad-scale transformation in the structure and 
ecological function of subalpine forests.
    In addition, we found population decline to be pervasive across all 
but the smallest size-classes of subalpine species (Fig. 3). Hence, our 
results indicate that subalpine forests of the western U.S. have, on 
average, become younger and thinner over the last 2 decades. Of all 
species examined herein, the size-density distributions of subalpine 
fir and Engelmann spruce are arguably the most likely to exist within 
their historic range of variability as both species tend to occur in 
cool, moist forests characterized by infrequent stand-replacing fires 
(i.e., effects of fire suppression are marginal relative to dry 
forest).\43\ The pervasive, size-dependent decline we observe in 
subalpine fir and Engelmann spruce is thus particularly concerning, 
indicating the size-distribution of each species may be beginning to 
depart from historically stable conditions. In contrast, decades of 
fire suppression and intensive harvesting in the western U.S. have 
resulted in an overabundance of mature, homogeneous lodgepole pine 
forest that is highly susceptible to native insect outbreaks.\37\ As 
such, reversion to historical conditions would require an increase in 
heterogeneity in the size-distribution of lodgepole pine at the 
landscape-level. Instead, the size-dependent patterns of decline we 
observe in lodgepole pine is indicative of increased homogeneity in the 
species' size-distribution, where small-diameter stems have become 
increasingly common relative to large-diameter stems despite a decline 
in relative tree density across nearly all tree size-classes (younger, 
thinner, more structurally homogeneous forests).
    Our results further indicate that insect outbreaks were >2.5 times 
more important than other disturbance types in driving relative density 
shifts of lodgepole pine and Engelmann spruce over the study period 
(Fig. 5), likely linked to recent outbreaks of mountain pine beetle 
(Dendroctonus ponderosae),\44\ and spruce beetle (Dendroctonus 
rufipennis),\45\ respectively. As both mountain pine beetle and spruce 
beetle have shown preference for large hosts (i.e., large-diameter 
trees), heightened insect-pest activity may explain size-dependent 
patterns of decline in lodgepole pine and Engelmann spruce. In 
contrast, we determined wildfire to be more than three times more 
important than other disturbance types in driving relative density 
shifts of subalpine fir (Fig. 5), and recent increases in the extent 
and frequency of wildfire 25, 46 could potentially explain 
size-dependent decline observed in the species. Specifically, increases 
in fire probability (and disturbance probability more generally) are 
likely to coincide with reduced mean stand age \21\ and subsequent 
decline in populations of large trees across a landscape. 
Interestingly, we found the relative density of lodgepole pine and 
Engelmann spruce increase, on average, in response to disease 
outbreaks, opposite their response to other disturbance types. We argue 
this result may arise from inter-specific compensatory responses to 
host-specific pathogens and/or mortality complexes. That is, one 
species may benefit from the targeted mortality of a competing species 
within a stand. It is likely that diseases affecting quaking aspen 
(e.g., sudden aspen decline \47\) and subalpine fir (e.g., subalpine 
fir decline \48\) may result in a positive growth response of competing 
lodgepole pine and Engelmann spruce, thereby increasing their relative 
density within affected stands.
    We observed the highest rates of range-average population expansion 
in Douglas-fir (17.1%R0.02 over the study period) and ponderosa pine 
(6.9%R0.03 over the study period; Fig. 2), widespread montane conifers 
that together represent 21.2% of all trees across the western U.S. It 
is important to note the population expansion observed for Douglas-fir 
and ponderosa pine may not be desirable in many settings, particularly 
in dry forests where both species occur frequently as canopy 
dominants49,50. Across the western U.S., decades of fire exclusion have 
created overstocked stand conditions that increase the probability of 
high-severity disturbance (i.e., wildfire, insect outbreak) 
51, 52 and may degrade forest resilience.\37\ In many cases, 
management aims to reduce tree density via stand thinning and fuels 
reduction. Hence high rates of relative density increases observed in 
Douglas-fir and ponderosa pine in the interior Pacific Northwest and 
portions of the Rocky Mountain region (Fig. 4), may be of substantial 
concern to forest managers. In contrast, patterns of decreased relative 
density of ponderosa pine and Douglas-fir observed in the Southern 
Rocky Mountains may be indicative of tree populations shifting nearer 
historic relative densities (Fig. 4).
    Divergence in both sign and magnitude of relative density shifts 
across size-distributions of ponderosa pine and Douglas-fir is 
indicative of broad-scale shifts in the structure of montane coniferous 
forests in the western U.S. Specifically, a peak in population 
expansion is evident among the 50-75th percentile of tree size-classes 
in both species, and potentially arises as a legacy of widespread 
logging during the 19th and early 20th century (i.e., owing to 
simultaneous maturation of stands across a broad spatial domain).\51\ 
Furthermore, population decline in the smallest size classes of 
Douglas-fir and ponderosa pine may potentially be linked to heightened 
wildfire activity during the study period,\46\ as fire was more than 
twice as important than other disturbance types in driving change in 
relative density in Douglas-fir, and more than five times as important 
in ponderosa pine (Fig. 5). That is, increased wildfire activity may 
have contributed to desirable change in the structure of montane 
coniferous forests (i.e., reduced relative density of small trees) over 
the last 2 decades in the western U.S., underscoring the potential for 
fire (both managed fire and wildfire) to foster forest resilience and 
contribute to restoration efforts in fire-adapted forests.\53\
    We found that large-diameter populations of Douglas-fir and 
ponderosa pine outperformed (i.e., exhibited higher positive change in 
relative density) small-diameter populations of the same species 
between 2001 and 2018 in the western U.S. (Fig. 3), opposite the 
pattern observed in subalpine species. In fact, we observed significant 
expansion among the largest-diameter populations of both species across 
the region. This surprising result contradicts previously described 
patterns of global decline of large-diameter trees,\41\ suggesting that 
such patterns may vary strongly across species and ecosystem 
associations in temperate forests (e.g., subalpine vs. montane 
ecosystems). Yet, pervasive increases in the relative density of medium 
and large-diameter montane conifers may be highly undesirable in some 
settings. Specifically, the structure of many dry, fire prone forest 
types of the western U.S. have shifted towards dense, closed-canopy 
stand conditions that are highly susceptible to crown fire and 
outbreaks of native insect and pathogens.\52\ As Douglas-fir and 
ponderosa pine are common canopy dominants in dry forest types, our 
results may indicate that such systems have diverged further from their 
historic natural range of variability over the last 2 decades.
    Elevated rates of population decline were evident for quaking aspen 
during the study period, pervasive across the range of the species 
(Fig. 4) and across its size-distribution (Fig. 3) in the western U.S. 
It is not inherently surprising to observe population decline in 
quaking aspen given recent spikes in mortality associated with sudden 
aspen decline.47, 54 However, the rate of population decline 
observed herein is particularly severe (20.2%R0.04% over the 18 year 
study period) and serves as a useful baseline to assess the performance 
of other species. Notably, the rates of range-average decline observed 
for Engelmann spruce and lodgepole pine exceed that of quaking aspen. 
Population decline of quaking aspen has received substantial attention 
in the forest ecology literature,54, 55, 56 however decline 
of Engelmann spruce has received far less. The disproportionate focus 
on quaking aspen decline in the literature (and lack of focus on other 
declining species), emphasizes the need for large-scale, comprehensive 
assessments of changes in forest composition and structure in the 
western U.S. and temperate forests elsewhere.
    We found woodland species (i.e., Utah juniper and common pinyon) to 
exhibit the highest degree of population stability across their ranges 
in the western U.S., relative to other top species. Pinyon-juniper 
woodlands of the southwestern U.S., where both Utah juniper and common 
pinyon occur as dominant species,\50\ have experienced dramatic 
expansions in tree density and equally dramatic tree mortality events 
over the past century.57, 58 However, inadequate 
understanding of historic disturbance regimes and tree population 
dynamics of pinyon-juniper woodlands make it difficult to conclude if 
such changes are beyond their natural range of variation.\57\ It is 
important to note that our results do not preclude such striking change 
at spatial and/or temporal domains not addressed herein. Rather, our 
results indicate the net responses of Utah juniper and common pinyon 
populations are relatively stable across broad spatial domains 
(species' ranges) and a relatively short period of time (18 years).
    The development of methods to quantify the joint demographic 
response of tree populations to novel environmental and anthropogenic 
stressors is among the most important advances required to improve 
predictions of future change in forest composition, structure, and 
function, and hence inform the management of forest ecosystem 
services.14, 19, 59 Herein, we present the FSI as one such 
method. The FSI is a standardized index of temporal change in relative 
live tree density that can be applied in forests of any community and 
or structural type. Specifically, the FSI weights observed changes in 
live tree density (e.g., absolute change in tree abundance) and tree 
size (e.g., tree basal area) against those expected under allometric 
size-density laws.16, 17 Hence, although most common indices 
of forest change (e.g., mortality rate) are confounded by transient 
dynamics in tree demography arising from metabolic scaling and density-
dependent mortality,15, 16, 20 the FSI is independent of 
these transient dynamics by design. As such, the FSI may yield simple, 
accurate measures of shifts in the structure and composition of forests 
when other common indices of forest change cannot.
    The simplicity, flexibility, and highly informative nature of the 
FSI make it well suited for application in a wide range of ecological 
settings, and we expect the index to be applied in similar studies to 
assess broad-scale changes in forest composition and structure in other 
forested regions across the globe. The FSI relies on temporally 
replicated data (i.e., ideally from a large number of samples) to 
derive inference of forest change, however the form of data required by 
the index are quite simple. For example, all estimates presented herein 
were derived from basic measures of tree density (e.g., TPH), tree size 
(e.g., diameter at breast height; DBH), and binary codes indicating the 
presence or absence of disturbance at measurement sites. As such, the 
FSI is uniquely well suited for applications using data collected in 
large-scale National Forest inventories. To this end, we provide a 
flexible implementation of the FSI in the publicly available R package, 
rFIA60, for application of the index using data collected by the U.S. 
Forest Service FIA program.
    Increased disturbance activity has been documented across temperate 
forests in recent decades,12, 34, 35 and forests of the 
western U.S. are no exception.29, 46 As disturbances modify 
forest structure and regulate tree population dynamics,\21\ our 
observation of recent broad-scale shifts in relative tree density 
across the western U.S. is not inherently surprising. However, the rate 
and pattern of change we observe across species, species-size 
distributions, and species ranges is alarming and in many cases 
undesirable. Furthermore, results of our efforts to quantify the 
importance of major forest disturbances in driving change in tree 
populations provide a unique opportunity to assess the vulnerability of 
tree species to sustained shifts in forest disturbance regimes, as 
expected under global climate change.2, 12 Importantly, the 
temporal frame of this study (18 years) is relatively short given the 
long life-spans of many tree species in the western U.S. (i.e., 
individuals may live for multiple hundreds of years). As such, it is 
unclear how the patterns of change we observe herein will translate to 
long-term trends in forest dynamics in the region, highlighting an 
important challenge for future research. Nevertheless, our results 
offer an early warning of recent, widespread change in forest 
composition and structure across the western U.S., and suggest that 
sustained anthropogenic and natural stress are likely to result in 
broad-scale change of temperate forests globally.
Methods
Field observations
    Since 1999, the FIA program has operated an extensive, nationally 
consistent forest inventory designed to monitor changes in forests 
across all lands in the U.S.\61\ We used FIA data from ten states in 
the continental western U.S. (Washington, Oregon, California, Idaho, 
Montana, Utah, Nevada, Colorado, Arizona, and New Mexico) to quantify 
shifts in relative live tree density, excluding Wyoming due to a lack 
of repeated censuses (Fig. 1). This region spans a wide variety of 
climatic regimes and forest types, ranging from temperate rain forests 
of the coastal Pacific Northwest to pinyon-juniper woodlands of the 
interior southwest.\62\ Although the spatial extent of the FIA plot 
network represents a large portion of the current range of all species 
examined in this study (Table 1), substantial portions of some species 
ranges (e.g., Douglas-fir) extend beyond the study region into Canada 
and/or Mexico and therefore were not fully addressed here.
    The FIA program measures forest attributes on a network of 
permanent ground plots that are systematically distributed at a rate of 
1 plot per 2,428 hectares across the U.S.\61\ For trees, 12.7 cm DBH 
and larger, attributes (e.g., species, DBH, live/dead) are measured on 
a cluster of four 168 m\2\ subplots.\61\ Trees 2.54-12.7 cm DBH are 
measured on a microplot (13.5 m\2\) contained within each subplot, and 
rare events such as very large trees are measured on an optional 
macroplot (1012 m\2\) surrounding each subplot.\61\ In the event a 
major disturbance (i.e., >1 acre in size, resulting in mortality or 
damage to >25% of trees) has occurred between measurements on a plot, 
FIA field crews record the primary disturbance agent (e.g., fire) and 
estimated year of the event. In the western U.S., \1/10\ of ground 
plots are measured each year, with remeasurements first occurring in 
2011. Please see Data Availability for more information on forest 
inventory data accessibility.
Forest stability index
    Allometric relationships between size and density of live trees 
make it difficult to interpret many indices of forest change.\19\ Live 
tree density is expected to decline as trees grow in size, owing to 
increased individual demand for resources and growing space (i.e., 
competition).16, 23 The expected magnitude of change in tree 
density, given some change in average tree size, varies considerably 
across forest communities,\63\ site conditions,\64\ and stand age 
classes.\23\ Thus, we posit it is useful to contextualize observed 
changes in live tree density relative to those expected given shifts in 
average tree size within a stand. To this end, we developed the FSI, a 
measure of change in relative live tree density that can be applied in 
stands of any forest community and/or structural type.
    To compute the FSI, we first develop a model of maximum size-
density relationships for tree populations in our study system (Fig. 
6). This model describes the theoretical maximum live tree density 
(Nmax; in terms of tree number per unit area) attainable in 
stands as a function of their average tree size (S) and will be used as 
a reference curve to determine the proportionate live tree density of 
observed stands (i.e., observed density with respect to theoretical 
maximum density). We use average tree basal area as an index of tree 
size (one, however, could also use biomass, volume, or other indices of 
tree size). For stand-type i, the general form of the maximum tree 
size-density relationship is given by


 where a is a scaling factor that describes the maximum tree density 
at S=1 and r is a negative exponent controlling the decay in maximum 
tree density with increasing average tree size. Such allometric size-
density relationships (i.e., power functions) are widely accepted as 
quantitative law describing the behavior of even-aged plant populations 
under self-thinning conditions,16, 17 and have been used 
extensively to describe relative stand density in 
forests.23, 24 As detailed below, we allow both a and r to 
vary with stand-type i, as maximum size-density relationships have been 
shown to vary across forest communities and ecological settings.63, 65 
Allowing a and r to vary by forest community type, for example, allows 
us to acknowledge that the maximum tree density attainable in a 
lodgepole pine stand is likely to differ from that of a pinyon-juniper 
stand with the same average tree size.
Fig. 6: Maximum size-density relationship for an example stand-type


          Individual points represent observed stand-level indices of 
        tree density (N) and average tree size (S). Maximum tree 
        density (Nmax) is modeled as a power function of 
        average tree size within a stand. Here, we use quantile 
        regression to estimate Nmax as the 99th percentile 
        of N conditional on S. The resulting maximum size-density curve 
        can then be used to compute the relative density of observed 
        stands (RD), where relative density is defined as ratio of 
        observed tree density (N) to maximum theoretical density 
        (Nmax), given S. Source data are provided as a 
        Source Data file.

    We next define an index of the relative density of a population of 
trees j (e.g., species, Pinus edulis) within a stand of type i (e.g., 
forest community type, pinyon/juniper woodland)


 where N is the density represented by tree h (in terms of tree number 
per unit area), and S is an index of individual-tree size (e.g., basal 
area, as used here). The denominator of Equation (2) represents the 
maximum tree density attainable in a stand of type i with average tree 
size equal to the size of tree h. We therefore express the relative 
density of a population j within stand-type i as a sum of the relative 
densities represented by individual trees within the stand. RD can be 
interpreted as the proportionate density, or stocking, of a population 
of trees within stand, where values range from 0 (population j is not 
present within a stand) to 1 (population j constitutes 100% of a stand 
and the stand is at maximum theoretical density given its size 
distribution). As we do in this study, one may apply any range of 
estimators to summarize the expected relative density of a population 
of trees j across a range of different stand-types (e.g., estimate the 
mean and variance of RDj across a broad region containing 
many different stand-types).
    It is important to note that Equation (2) is approximately equal to 
a simpler


method using aggregate indices (i.e.,          when tree size-
distributions are nor-

mally distributed (even age-structures). However, the use of aggregate 
indices introduces class aggregation bias that results in 
overestimation of relative density in stands with non-normal size 
distributions (i.e., uneven age-structures), consistent with other 
indices of relative tree density.\66\ In contrast, summing tree-level 
relative densities eliminates such bias and allows RD to accurately 
compare density conditions across stands in very different structural 
settings (e.g., even-aged plantation vs. irregularly structured old 
forest). Furthermore, the partitioning of relative density into tree-
level densities allows RD to be accurately summarized within tree size-
classes.\66\ That is, it is possible to explicitly estimate the 
contribution of tree size-classes to overall stand density using RD.
    For a given population j within stand-type i, we define the FSI as 
the average annual change in relative tree density observed between 
successive measurements of a stand


 where Dt is the number of years between successive measurement times 
t1 and t2 and DRD is the change in RD over Dt 
(i.e., RDt2-RDt1). The FSI may also be expressed 
in units of percent change (%FSI), where average annual change in 
relative tree density is standardized by previous relative density


 Here, stability is defined by zero net change in relative tree 
density over time (i.e., FSI equal to zero), but does not imply zero 
change in absolute tree density or tree size distributions. For 
example, a population exhibiting a decrease in absolute tree density 
(e.g., trees per unit area) may be considered stable if such decline is 
offset by a compensatory increase in average tree size. However, 
populations exhibiting expansion (i.e., 
RDt12) or decline (i.e., 
RDt1>RDt2) in relative tree density will be 
characterized by positive and negative FSI values, respectively.
Statistical analysis
    We computed the FSI for all remeasured FIA plots in the western 
U.S. (N = 24,229). We included plots on both public and private lands 
and considered all live stems (DBH %2.54 cm) in our analysis. As forest 
management can effect regional shifts in tree density, we excluded 
plots with evidence of recent (i.e., within 5 years of initial 
measurement) silvicultural treatment (e.g., harvesting, artificial 
regeneration, site preparation). All plot measurements occurred from 
2001 to 2018, with an average remeasurement interval of 9.78 years 
(R0.005 years). For brevity, we restricted our analysis to consider the 
eight most abundant tree species in the western U.S. We identified the 
most abundant tree species using the rFIA R package,\60\ defining 
abundance in terms of estimated total number of trees (DBH %2.54 cm) in 
the year 2018. We excluded species that exhibit non-tree growth habits 
(i.e., shrub, subshrub) across portions of the study region. All 
statistical analysis was conducted in Program R (4.0.0).\67\
    We developed a Bayesian quantile regression model to estimate 
maximum size-density relationships for stand-types observed within our 
study area. Here, we use TPH as an index of absolute tree density, 
average tree basal area (BA; equivalent to tree basal area per hectare 
divided by TPH) as an index of average tree size, and forest community 
type to describe stand-types. We produced stand-level estimates of TPH 
and BA from the most recent measurements of FIA plots that (1) lack 
evidence of recent (within remeasurement period or preceding 5 years) 
disturbance and/or silvicultural treatment and (2) exhibit 
approximately normal tree diameter distributions (i.e., even-aged). 
Here we define an approximately normal tree diameter distribution as 
exhibiting Pearson's moment coefficient of skewness between ^1 and 1.
    We transform the nonlinear size-density relationship to a linear 
function by taking the natural logarithm of TPH and BA, and use a 
linear quantile mixed-effects model to estimate the 99th percentile of 
TPH conditional on BA (i.e., in log-log space) for all observed forest 
community types. We allowed both the model intercept and coefficient to 
vary across observed forest community types (i.e., random slope/
intercept model), thereby acknowledging variation in the scaling factor 
(a) and exponent (r) of the maximum tree size-density relationship 
across stand-types. We place informative normal priors on the model 
intercept (m=7, s=1) and coefficient (m=0.8025, s=0.1) following the 
results of decades of previous research in maximum tree size-density 
relationships.16, 23, 63, 65
    The FIA program uses post-stratification to improve precision and 
reduce non-response bias in estimates of forest variables,\68\ and we 
used these standard post-stratified estimators to estimate the mean and 
variance of the FSI for each species across their respective ranges 
within the study area (see Code Availability for all relevant code). 
Further, the FIA program uses an annual panel system to estimate 
current inventories and change, where inventory cycles consist of 
multiple panels, and individual panels are comprised of mutually 
exclusive subsets of ground plots measured in the same year within a 
region. Precision of point and change estimates can often be improved 
by combining annual panels within an inventory cycle (i.e., by 
augmenting current data with data collected previously). We used the 
simple moving average estimator implemented in the rFIA R package \60\ 
to compute estimates from a series of eight annual panels (i.e., sets 
of plots remeasured in the same year) ranging from 2011 to 2018. The 
simple moving average estimator combines information from annual panels 
with equal weight (i.e., irrespective of time since remeasurement), 
thereby allowing us to characterize long-term patterns in relative 
density shifts. We determine populations to be stable if the 95% 
confidence intervals for range-averaged FSI included zero. 
Alternatively, if confidence intervals of range-averaged FSI do not 
include zero, we determine the population to be expanding when the 
estimate is positive and declining when the estimate is negative.
    To identify changes in species-size distributions, we used the 
simple moving average estimator to estimate the mean and variance of 
the FSI by species and size class across the range of each species 
within our study area. We assign individual trees to size-classes 
representing 10% quantiles of observed diameter distributions (i.e., 
diameter at 1.37 m above ground) of each species growing on one of 
seven site productivity classes (i.e., inherent capacity of a site to 
grow crops of industrial wood). That is, we allow size class 
definitions to vary among species and along a gradient of site 
productivity, thereby acknowledging intra-specific variation in 
diameter distributions arising from differences in growing conditions. 
The use of quantiles effectively standardizes absolute size 
distributions, simplifying both intra-specific and inter-specific 
comparison of trends in relative density shifts along species-size 
distributions.
    We assessed geographic variation in species relative density shifts 
at two scales: ecoregion divisions and subsections.\69\ Ecoregion 
divisions (shown for our study area in Fig. 1) are large geographic 
units that represent broad-scale patterns in precipitation and 
temperature across continents. Ecoregion subsections are subclasses of 
ecoregion divisions, differentiated by variation in climate, 
vegetation, terrain, and soils at much finer spatial scales than those 
represented by divisions. We again used the simple moving average 
estimator to estimate the mean and variance of the FSI by species 
within each areal unit (i.e., drawing from FIA plots within each areal 
unit to estimate mean and variance of the FSI). As a direct measure of 
changes in relative tree density, spatial variation in the FSI is 
indicative of spatial shifts in species distributions during the 
remeasurement interval (i.e., range expansion/contraction and/or 
within-range relative density shifts). That is, the distribution of 
populations shift toward regions increasing in relative density and 
away from regions decreasing in relative density during the temporal 
frame of sampling. We map estimates of the FSI for each areal unit to 
assess spatial patterns of changes in relative density and identify 
regions where widespread geographic shifts in species distributions may 
be underway.
    We sought to quantify the average effect of forest disturbance 
processes on changes in the relative density of top tree species in the 
western U.S. over the interval 2001-2018. To this end, we developed a 
hierarchical Bayesian model to determine the average severity and 
annual probability of disturbances (i.e., wildfire, insect outbreak, 
and disease) on sites where each species occurs. Average severity was 
modeled as 


 where yjk is the FSI of species j on plot k, aj 
is a species-specific intercept, bjl is a species-specific 
coefficient corresponding to the binary variable xlk that 
takes the value of 1 if disturbance l occurred within plot k 
measurement interval and 0 otherwise. The intercept and regression 
coefficients each received an uninformative normal prior distribution. 
The species-specific residual standard deviation wj received 
a uninformative uniform prior distribution.\70\
    On average, disturbance will occur at the midpoint of plot 
remeasurement periods, assuming temporal stationarity in disturbance 
probability over the study period. As plots in this study are 
remeasured on 10 year intervals, we assume that tree populations have, 
on average, 5 years to respond to any disturbance event. Hence, our 
definition of disturbance severity, bjl's, cannot be 
interpreted as the immediate change in relative tree density resulting 
from disturbance. Rather, disturbance severity (as defined here) 
includes the immediate effects of disturbance, as well as 5 years of 
change in relative tree density prior to and following disturbance 
(where disturbance is assumed to be functionally instantaneous).
    Annual probability of disturbance l on plot k was modeled as
    
    
 where Dtk is the number of years between successive 
measurements of plot k, viewed here as the number of binomial 
``trials,'' and cjl is the species-specific probability for 
disturbance which was assigned a beta(1,1) prior distribution. Hence, 
annual probability of disturbance is assumed to vary by species j and 
by disturbance type l.
    We estimate the mean effect of forest disturbance processes on 
changes in species-specific relative tree density by multiplying the 
posterior distributions of bjl and cjl. That is, 
we multiply species-specific disturbance severity by disturbance 
probability to yield an estimate of the mean change in relative density 
caused by disturbance over the study period. We then standardize these 
values across species by dividing by the average relative density of 
each species at the beginning of the study period. Thus, standardized 
values can be interpreted as the annual proportionate change in the 
relative tree density of each species resulting from disturbance over 
the period 2001-2018.
Reporting summary
    Further information on research design is available in the Nature 
Research Reporting Summary (https://www.nature.com/articles/s41467-020-
20678-z#MOESM2) linked to this article.
Data availability
    All forest inventory data used herein are publicly available in 
comma-delimited text format via the USDA Forest Service FIA data 
repository (https://apps.fs.usda.gov/fia/datamart/CSV/
datamart_csv.html). Source data are provided with this paper.
Code availability
    We have implemented computational routines for the FSI in the 
publicly available R package, rFIA.\60\ In addition, all custom code 
used herein is publicly available in the following permanent GitHub 
repository: https://github.com/hunter-stanke/Code-repository---NCOMMS-
20-20430.
    Received: 20 May 2020; Accepted: 1 December 2020; Published online: 
19 January 2021.

 
 
 
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Acknowledgements
    This work was supported by: National Science Foundation grants DMS-
1916395, EF-1253225, EF-1241874; U.S. Department of Agriculture, Forest 
Service, Region 9, Forest Health Protection, Northern Research Station; 
U.S. National Park Service; and Michigan State University 
AgBioResearch. The findings and conclusions in thispublication are 
those of the author(s) and should not be construed to represent any 
official U.S. Department of Agriculture or U.S. Government 
determination or policy.
Author information
Affiliations
    Department of Forestry, Michigan State University, East Lansing, 
MI, USA
Hunter Stanke, Andrew O. Finley & David W. MacFarlane
    School of Environmental and Forest Sciences, University of 
Washington, Seattle, WA, USA
Hunter Stanke
    Department of Geography, Environment, and Spatial Sciences, 
Michigan State University, East Lansing, MI, USA
Andrew O. Finley
    Forest Service, Northern Research Station, U.S. Department of 
Agriculture, St Paul, MN, USA
Grant M. Domke
    Northeast Temperate Inventory and Monitoring Network, U.S. National 
Park Service, Woodstock, VT, USA
Aaron S. Weed
Contributions
    H.S., A.O.F., G.M.D., A.S.W., and D.W.M. designed research; H.S. 
performed research; H.S. analyzed data; H.S., A.O.F., G.M.D., A.S.W., 
and D.W.M. wrote and reviewed the manuscript.
Corresponding author
    Correspondence to Hunter Stanke.
Ethics declarations
Competing interests
    The authors declare no competing interests.
Additional information
    Peer review information Nature Communications thanks Solomon 
Dobrowski, Monika Wulf and the other, anonymous, reviewer for their 
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available.
    Publisher's note Springer Nature remains neutral with regard to 
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    Open Access This article is licensed under a Creative Commons 
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     The Author(s) 2021.
                               Article 5


[https://advances.sciencemag.org/content/4/5/eaaq1012]
Science Advances
Research Article
Carbon dioxide (CO2) levels this century will alter the 
        protein, micronutrients, andvitamin content of rice grains with 
        potential health consequences for the poorest rice-dependent 
        countries
Chunwu Zhu,\1\ Kazuhiko Kobayashi,\2\ Irakli Loladze,\3\ Jianguo 
Zhu,\1\ Qian Jiang,\1\ Xi Xu,\1\ Gang Liu,\1\ Saman Seneweera,\4\ 
Kristie L. Ebi,\5\ Adam Drewnowski,\6\ Naomi K. Fukagawa,\7\ Lewis H. 
Ziska \8\ *
---------------------------------------------------------------------------
    \1\ State Key Laboratory of Soil and Sustainable Agriculture, 
Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, 
P.R. China.
    \2\ University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, 
Japan.
    \3\ Bryan College of Health Sciences, Bryan Medical Center, 
Lincoln, NE 68506, USA.
    \4\ Centre for Crop Health, University of Southern Queensland, 
Toowoomba, Queensland 4350, Australia.
    \5\ Center for Health and the Global Environment (CHanGE), 
University of Washington, Seattle, WA 98198, USA.
    \6\ Center for Public Health Nutrition, University of Washington, 
Seattle, WA 98195, USA.
    \7\ U.S. Department of Agriculture-Agricultural Research Service 
(USDA-ARS), Beltsville Human Nutrition Center, Beltsville, MD 20705, 
USA.
    \8\ USDA-ARS, Adaptive Cropping Systems Laboratory, Beltsville, MD 
20705, USA.
    * Corresponding author. Email: [email protected].
---------------------------------------------------------------------------
Abstract
    Declines of protein and minerals essential for humans, including 
iron and zinc, have been reported for crops in response to rising 
atmospheric carbon dioxide concentration, [CO2]. For the 
current century, estimates of the potential human health impact of 
these declines range from 138 million to 1.4 billion, depending on the 
nutrient. However, changes in plant-based vitamin content in response 
to [CO2] have not been elucidated. Inclusion of vitamin 
information would substantially improve estimates of health risks. 
Among crop species, rice is the primary food source for more than two 
billion people. We used multiyear, multilocation in situ FACE (free-air 
CO2 enrichment) experiments for 18 genetically diverse rice 
lines, including Japonica, Indica, and hybrids currently grown 
throughout Asia. We report for the first time the integrated 
nutritional impact of those changes (protein, micronutrients, and 
vitamins) for the ten countries that consume the most rice as part of 
their daily caloric supply. Whereas our results confirm the declines in 
protein, iron, and zinc, we also find consistent declines in vitamins 
B1, B2, B5, and B9 and, conversely, an increase in vitamin E. A strong 
correlation between the impacts of elevated [CO2] on vitamin 
content based on the molecular fraction of nitrogen within the vitamin 
was observed. Finally, potential health risks associated with 
anticipated CO2-induced deficits of protein, minerals, and 
vitamins in rice were correlated to the lowest overall gross domestic 
product per capita for the highest rice-consuming countries, suggesting 
potential consequences for a global population of approximately 600 
million.
Introduction
    One of the consequential impacts of rising carbon dioxide 
concentration ([CO2]) and climate change is expected to be 
on food security.\1\ This expected impact is due, in part, to the 
vulnerability of the global population to food supply: Depending on 
definition, up to one billion people are deemed food insecure.\2\ For 
example, harvests of staple cereal crops, such as rice and maize, could 
decline by 20 to 40% as a function of increased surface temperatures in 
tropical and subtropical regions by 2100 without considering the 
impacts of extreme weather and climate events.\3\ Overall, there has 
been a directed effort to understand the consequences of 
[CO2] and climate on agricultural production.4, 5
    However, the connection between food security and well-being 
extends beyond production per se; for example, dietary quality has a 
substantial influence on human health.\6\ Globally, insufficient 
micronutrients, protein, vitamins, etc. can contribute to nutritional 
deficiencies among two billion people in developing and developed 
countries.\7\ These deficiencies can directly (cognitive development, 
metabolism, and immune system) and indirectly (obesity, type 2 diabetes 
mellitus) affect human health on a panoptic scale.\8\
    The elemental chemical composition of a plant (that is, ionome) 
reflects a balance between carbon, obtained through atmospheric 
[CO2], and the remaining nutrients, obtained through the 
soil. As evidenced by over a hundred individual studies and several 
meta-analyses, projected increases in atmospheric [CO2] can 
result in an ionomic imbalance for most plant species whereby carbon 
increases disproportionally to soil-based nutrients.9-11 
This imbalance, in turn, may have significant consequences for human 
nutrition 12, 13 including protein and micronutrients. 
However, at present, no information is available regarding a key 
constituent of nutrition, vitamin content; as a result, no integrated 
assessment (protein, micronutrients, and vitamins) is available.
    The consequences of CO2-induced qualitative changes may 
be exacerbated where food diversity is limited, that is, where 
populations rely heavily on a single plant-based food source. In this 
regard, rice supplies approximately 25% of all global calories, with 
the percentage of rice consumed varying by socioeconomic status, 
particularly in Asia.\14\ Rice is considered among the most important 
caloric and nutritional sources particularly for low- and lower-middle-
income Asian countries.\15\
    Therefore, for those populations that are highly rice-dependent, 
any CO2-induced change in the integrated nutritional value 
of rice grains could disproportionally affect health. We use a 
multiyear, multilocation, multivarietal evaluation of widely grown, 
genetically diverse rice lines at ambient and anticipated end-of-
century [CO2] to (i) quantify varietal response to changes 
in dietary components, including protein, iron, calcium, zinc, vitamin 
E, and the vitamin B complex, and (ii) socioeconomically calculate any 
CO2-induced deficits in these nutritional parameters for the 
ten most rice-centric countries globally, as a function of gross 
domestic product (GDP) per capita.
    Although end-of-century [CO2] projections vary, it is 
very likely that actual atmospheric [CO2] will reach 570 
mmol mol-1 before the end of this century.\16\ Global 
[CO2] is expected to reach these levels even as additional 
steps are taken to decrease emissions, due, in part, to the projected 
energy usage, the longevity of the CO2 molecule in the 
atmosphere, and the temporal delay in reducing [CO2] 
emissions before mid-century.\17\ Overall, the experimental 
concentrations used here for the elevated [CO2] treatment 
(568 to 590 mmol mol-1) reflect the reality that those born 
today will be eating rice grown at [CO2] of 550 mmol 
mol-1 (or higher) within their lifetimes.
Results
    When grown under field conditions at these anticipated 
[CO2] a significant reduction (an average of ^10.3%) in 
protein relative to current [CO2] was observed for all rice 
cultivars (Fig. 1). Similarly, significant reductions in iron (Fe) and 
zinc (Zn) were also observed (^8.0 and ^5.1%, respectively) among all 
rice cultivars tested (Fig. 2). On the basis of [CO2] 
assessment per se, there were no significant site difference effects on 
rice grain quality between Japan and China (P = 0.26, 0.17, and 0.10 
for protein, iron, and zinc, respectively).
Fig. 1


          Average reduction in grain protein at elevated relative to 
        ambient [CO2] for 18 cultivated rice lines of 
        contrasting genetic backgrounds grown in China and Japan using 
        FACE technology.
          A country by [CO2] effect on protein reduction was 
        not significant (P = 0.26). Bars are RSE. *P<0.05 and **P<0.01 
        (see Methods for additional details).
Fig. 2


          Average reduction in grain micronutrients, iron (Fe), and 
        zinc (Zn) concentration at elevated relative to ambient 
        [CO2] for 18 cultivated rice lines of contrasting 
        genetic backgrounds grown in China and Japan using FACE 
        technology.
          A country by [CO2] effect was not significant for 
        either micronutrient [P = 0.17 and 0.10 for iron (Fe) and zinc 
        (Zn), respectively] so data from both locations are shown. Bars 
        are RSE. *P<0.05 and **P<0.01 for a given cultivar. 
        CO2; **P<0.01 is based on all cultivars (see Methods 
        for additional details).

    The rice lines chosen reflect a wide genotypic and phenological 
range, suggesting that the declines in nutrient parameters observed 
here are representative of rice in toto. However, a larger sample size 
would be of benefit both to confirm these findings and, if possible, to 
determine whether any lines may be preferred for improving protein or 
micronutrient availability as [CO2] increases.
    Regarding the B vitamin complex, significant reductions in vitamins 
B1 (thiamine), B2 (riboflavin), B5 (pantothenic acid), and B9 (folate) 
were observed in response to projected CO2 levels with 
average declines among cultivars of ^17.1, ^16.6, ^12.7, and ^30.3%, 
respectively (Fig. 3). As observed for protein and minerals, no 
increase in these parameters was detected for any of the 18 rice lines 
evaluated; in addition, no significant [CO2] by cultivar 
interactions were noted (Fig. 3). In contrast, increases were observed 
on average for vitamin E (a-tocopherol) (fig. S1).
Fig. 3


          CO2-induced reductions in vitamins B1 (thiamine), 
        B2 (riboflavin), B5 (pantothenic acid), and B9 (folate) by 
        cultivar.
          No significant effect was observed for vitamin B6 
        (pyridoxine), and results are not shown. Analysis was conducted 
        only for the China FACE location. Bars are RSE. *P<0.05 and 
        **P<0.01 for a given cultivar. CO2; **P<0.01 is 
        based on all cultivars (see Methods for additional details).

    Although these data indicate that [CO2] affects nutrient 
composition, the impact of these qualitative changes on health will 
vary as a function of rice consumed relative to the total caloric 
intake. Previous calculations of the impact of rising CO2 on 
human nutrition relied on Food and Agriculture Organization (FAO) food 
balance sheets combined with Monte Carlo simulations run on the range 
of projected declines of zinc, protein, and iron.12, 13 
Here, we also rely on FAO food balance sheets but use an economic 
approach whereby average qualitative changes observed with 
[CO2] as a function of rice consumption for the top ten 
rice-consuming countries as of 2013 are compared with GDP per capita of 
that country. In this context, any protein and mineral deficits (Fe + 
Zn), associated with higher CO2 values, are observed to be 
greater for those countries with the lowest overall GDP per capita (for 
example, Bangladesh and Cambodia) (Fig. 4). The reductions in vitamin B 
(B1, B2, B5, and B9) availability were greatest for these same 
countries (Fig. 4). Similarly, the increase in vitamin E with higher 
CO2 levels and the subsequent consumption is proportionally 
greater for those poorer countries that ingest greater quantities of 
rice (Fig. 4).
Fig. 4


          Projected [CO2]-induced deficits in protein and 
        minerals (Fe and Zn) and cumulative changes in vitamin B and 
        cumulative changes in vitamin E derived from rice as a function 
        of GDP per capita.
          Data are based on 2011/2013 FAO food balance sheets for rice 
        consumption and 2011/2013 World Bank estimates of GDP per 
        capita per country.

    There is growing evidence demonstrating a clear link between crop 
growth at projected increases in [CO2] and changes in 
nutritional quality including, but not limited to, protein, secondary 
compounds, and minerals (for example, Zn).9-11, 18, 19 The 
basis for the CO2-induced changes in crop quality is still 
being elucidated, in part, because increasing [CO2] 
influences several biophysical processes.\20\ However, for near-term 
projections of [CO2], the qualitative decline can be 
reasonably (given the accuracy of the current data) approximated as 
linear (for example, protein).\21\
    The nutritional data reported here for elevated [CO2] 
confirm that deficits in protein, zinc, and iron may occur even among 
genetically diverse rice lines grown in different 
countries.11, 22 In addition, the current data indicate, for 
the first time, a pattern in the changes in vitamin content, that is, 
the extent of observed variation between vitamin B (B1, B2, B5, B6, and 
B9) and vitamin E (a-tocopherol).
    Variation among [CO2]-induced changes in secondary 
compounds, such as vitamins, may relate to the well-established decline 
of nitrogen in plants exposed to elevated [CO2] [for 
example, see the study of Taub, et al.\9\]. The effect of increasing 
levels of [CO2] on vitamin levels could therefore be 
inversely correlated with the molecular fraction of nitrogen within the 
vitamin. This was observed for rice in the current study (r\2\ = 0.82) 
(Fig. 5), consistent with the carbon-nutrient balance hypothesis; \23\ 
at least in the context of rapid increases in atmospheric 
[CO2] and carbon availability [but see the study of 
Hamilton,  et al.\24\], that is, the levels of nitrogen containing 
vitamins decreased (B vitamin group), whereas the level of carbon-based 
compounds (vitamin E) increased. Additional information regarding the 
effects of [CO2] on nutritional quality is obviously 
desired; however, this relationship could provide initial guidance as 
to the aspects of rice grain chemistry affected by increasing 
atmospheric [CO2].
Fig. 5


          Average change in vitamin concentration (as percentage) in 
        response to anticipated, relative to current, [CO2] 
        RSE as a function of the ratio of the molecular weight of 
        nitrogen (N) to the molecular weight of the vitamin.
          There was a highly significant correlation between the amount 
        of N present in the vitamin and the overall decrease or 
        increase in response to higher [CO2].
Discussion
    As of 2013, approximately 600 million individuals, primarily in 
Southeast Asia [the countries of Bangladesh, Cambodia, Indonesia, Lao 
People's Democratic Republic (PDR), Madagascar, Myanmar, and Vietnam], 
consume %50% of their per capita dietary energy and/or protein directly 
from rice.25, 26 The data shown here provide the first integrated 
assessment of [CO2]-induced changes in nutritional quality 
(protein, minerals, and vitamins) for many of the most widely grown 
rice lines; as such, they indicate that, for key dietary parameters, 
the [CO2] likely to occur this century will add to 
nutritional deficits for a large segment of the global population.
    In assessing the outcome of the [CO2]-induced dietary 
changes for rice in the current study, it is evident (Fig. 4) that the 
bulk of these changes, and the greatest degree of risk, will occur 
among the highest rice-consuming countries with the lowest GDP. 
However, as income increases, consumers prefer more diverse caloric 
sources, with a greater emphasis on protein from fish, dairy, and meat 
as per western foods.\27\ Therefore, future economic development could 
potentially limit future CO2-induced changes in rice 
nutrition. For example, in Japan, rice accounted for 62% of total food 
energy consumption in 1959, but that share fell to 40% by 1976 and, in 
recent years, is <20%; \28\ in South Korea, per capita rice consumption 
almost halved since 1975.\29\ However, strong, sustained economic 
growth cannot be assumed for all rice-consuming countries. For example, 
in Bangladesh, 75% of the total caloric supply per capita came from 
rice in 1990; 23 years later, in 2013, it was 70% (http://
faostat.fao.org/beta/en/#data/FBS); in Madagascar, the percentage of 
rice consumption has increased since 1990.\25\ In addition, other 
countries, such as Guinea, Senegal, and Cote d'Ivoire, have become more 
reliant on rice as a percentage of their caloric supply (20 to 40% as 
of 2011).\30\ Overall, although the top rice-consuming countries are 
likely to change in the coming decades, the reliance on rice globally 
as a dietary staple will continue.
    Specific health outcomes of consuming rice with reduced nutritional 
quality are also difficult to forecast. Staple foods, such as rice, are 
widely available and affordable for most of the world's population, 
particularly the poor. It is understood that undernutrition can put 
people at risk in low-income countries for a wide range of other 
adverse health outcomes, particularly stunting, diarrheal disease, and 
malaria.\31\ For example, Kennedy, et al.,\15\ found that the 
percentages of children under 5 years of age who suffer from stunting, 
wasting, or are underweight are generally high in countries with very 
high per capita rice consumption. Overall, the current data suggest 
that, for these countries, any [CO2]-induced change in 
nutritional quality would likely exacerbate the overall burden of 
disease and could affect early childhood development.
    It is difficult, without a great deal of additional socioeconomic 
data at the country level (which is often unavailable), to provide 
exact estimates of nutritional deficits (protein, minerals, and 
vitamins) and associated health consequences likely to incur for rice-
dependent populations. Yet, CO2-induced reductions in these 
qualities and associated risks of undernutrition or malnutrition are 
likely to transcend the entire food chain, from harvest to consumption, 
especially for the poorest people within a country or region.
    Is there a way then to reduce--or negate--this risk? Cultivar 
selection, either through traditional breeding or genetic modification, 
to provide nutritionally superior rice with additional CO2 
is an obvious strategy. The current data for a genetically diverse set 
of rice lines suggest that, at least for some characteristics (for 
example, protein and vitamin B2), many additional lines would need to 
be screened; furthermore, at present, it can take many years, even 
decades, to identify, cultivate, and distribute new cereal lines that 
are adapted to a changing climate.\32\ In addition, other aspects of 
climate change, especially temperature, would need to be considered. 
For example, previous work indicated that rising temperature per se can 
also reduce protein concentration in rice.\33\ Although the extent of 
future surface temperatures would vary depending on location, 
temperature and [CO2] should also be evaluated concurrently 
regarding rice nutritional impacts in future assessments.
    In addition, management could include application of mineral 
fertilizers or postharvest biofortification. On the consumer side, 
education about the role of rising [CO2] on nutrition, 
including opportunities to implement favorable nutrition practices and 
food fortification, may also provide opportunities to maintain 
nutritional integrity. Finally, there is an obvious need for the 
research community, including agronomists, physiologists, 
nutritionists, and health care providers, to accurately quantify the 
exact nature of the [CO2]-induced changes in human 
nutritional status and their associated health outcomes.
    Whereas much remains to be done, the current study provides the 
first evidence that anticipated [CO2] will result in 
significant reductions in integrated rice quality, including protein, 
minerals, and vitamin B, for a genetically diverse and widely grown set 
of rice lines. Occurrence of these nutritional deficits will most 
likely affect the poorest countries that are the most rice-dependent. 
Overall, these results indicate that the role of rising 
[CO2] on reducing rice quality may represent a fundamental, 
but underappreciated, human health effect associated with anthropogenic 
climate change.
Methods
Free-air CO2 enrichment sites
    The multiyear study was conducted at free-air CO2 
enrichment (FACE) facilities in two countries: (i) China [at Zhongcun 
Village (119420"E, 32355"N), Yangzhou City, Jiangsu Province; as 
part of the Yangtze River Delta region, a typical rice growing region 
\34\] and (ii) Japan [at Tsukuba (3558N, 13960E), in Ibaraki 
Prefecture within farmer's fields \35\]. Eighteen rice lines 
representing varietal groups of cultivated rice (Indica and Japonica) 
and new hybrid lines were chosen. These lines were, for the most part, 
representative and widely grown in the geographical regions where the 
FACE facilities were located (Table 1).

              Table 1. Characteristics of rice lines used.
------------------------------------------------------------------------
    Cultivar          Origin          Subgroup            Comments
------------------------------------------------------------------------
86Y8              China           Hybrid            Bred for disease-
                                                     resistance; high
                                                     ripening rate
Bekoaoba          Japan           Japonica          Bred for lodging
                                                     resistance, used in
                                                     silage
Hokuriku 193      Japan           Indica            High-yielding, blast-
                                                     resistant
Hoshiaoba         Japan           Japonica          Cultivar used for
                                                     silage and
                                                     bioenergy
IR72              Philippines     Indica            Semi-dwarf, often
                                                     used as check
                                                     cultivar
Koshihikari       Japan           Japonica          Widely grown in
                                                     Japan
Lemont            United States   Japonica          Semi-dwarf grown in
                                                     Mississippi Delta
Milyang 23        Korea           Indica            High-yielding,
                                                     cadmium accumulator
Momiroman         Japan           Japonica          Medium grain, high-
                                                     yielding variety
Nipponbare        Japan           Japonica          Genome-sequenced
Liang You 084     China           Hybrid            Grown extensively in
                                                     southeast China
Takanari          Japan           Indica            Widely grown in
                                                     Japan
Wuyunjing 21      China           Japonica          Grown extensively in
                                                     East China
Wuyunjing 23      China           Japonica          Grown extensively in
                                                     East China
Yangdao 6 hao     China           Indica            Grown extensively in
                                                     East and Central
                                                     China
Yliangyou         China           Hybrid            Recently introduced
                                                     (2008) hybrid line
Yongyou 2640      China           Hybrid            Widely planted in
                                                     lower Yangtze River
Zhonghua 11       China           Japonica          Disease-resistant
                                                     line used in
                                                     breeding
------------------------------------------------------------------------

CO4 and environmental parameters
    A complete description of CO2 control for the China and 
Japan locations can be found in the studies of Zhu, et al.,\34\ and 
Hasegawa, et al.,\35\ respectively. The operation and control systems 
for the China FACE facilities were the same as those at the Japan FACE 
site. Briefly, each site consisted of identical octagonal rings imposed 
on farmer's fields with three rings (China) or four rings (Japan) 
receiving pure CO2 supplied from polyethylene tubing 
installed horizontally on the periphery of the FACE ring at 30 cm above 
the rice canopy (elevated CO2 treatment), with additional 
rings (three and four, respectively) that did not receive supplemental 
CO2 (ambient CO2 treatment). The concentration of 
CO2 was monitored at the center of each ring, and using the 
ambient [CO2] as the control, a proportional-integral-
derivative algorithm was used (relative to the ambient control) to 
regulate the injection and direction of CO2 in the elevated 
ring. Rings were spaced at 90-m intervals to prevent CO2 
contamination between plots. Ring diameters varied between locations 
(14 and 17 m for the Tsukuba and Zongcun sites, respectively); 
[CO2] was controlled to within 80% of the set point for >90% 
of the time during the growing season for each location and year. For 
the China location, the average daytime [CO2] levels at 
canopy height for the elevated treatment were 571, 588, and 590 mmol 
mol-1 for 2012, 2013, and 2014, respectively; for the Japan 
location, the season-long daytime average CO2 was 584 mmol 
mol-1 (2010, Tsukuba); ambient [CO2] varied from 
374 to 386 regardless of location.
    Rice fields in all locations were flood-irrigated and grown as 
``paddy'' rice, as consistent with local practices. For the China 
location, the average growing season temperature was 24.4, 24.8, and 
22.1 C for 2012, 2013, and 2014, respectively; for Japan, the growing 
season temperature was 24.6 C for the Tsukuba location in 2010. The 
soil type in the China location was classified as Shajiang-Aquic 
Cambiosol with a sandy loam texture. The soil type at Tsukuba, Japan is 
Fluvisols, typical of alluvial areas. Fertilizer was applied at rates 
to maximize commercial yield, consistent with location; any additional 
pesticides were consistent with cultural agronomic practices for the 
given region. Sowing and transplanting methods are described 
elsewhere.34, 35 At seed maturity, 1 to 2 m\2\ per 
CO2 ring, per cultivar, per year, and per location were 
harvested for yield assessment.
Nutrient analysis
    For the China FACE, a subsample (500 g) of grain was frozen before 
analysis. Dehusked (unpolished) brown (raw and uncooked) rice (100 g) 
was homogenized to a fine powder using a Mix/Mill Grinder, sifted 
through a 100-mesh sieve, and then dried to a constant weight at 70 C. 
A 0.5-g sample was added to a graphite tube for digestion, 0.2 ml of 
pure deionized (DI) water was added, followed by 8 ml of 
HNO3, and digested for 24 hours. An additional 2 ml of 
HCLO4 was then added. Digestion temperature was regulated 
until clear color was obtained. Finally, DI water was added to increase 
any remaining solution to 50 ml. Inductively coupled plasma (ICP) 
atomic emission spectrometry (AES) (Optima 8000, PerkinElmer) was used 
to determine Ca content, whereas ICP-mass spectrometry (MS) (7700, 
Agilent) was used to determine Fe and Zn content. Elemental analyses 
for the samples from the Tsukuba FACE location are described by 
Dietterich, et al.\36\ Briefly, the air-dried husked (but unpolished) 
brown rice grains were air-dried and ground as described previously. 
Nitrogen was analyzed with a Leco TruSpec CN analyzer. Fe, Zn, and Ca 
were determined with an ICP optical emission spectrophotometer. Note 
that brown rice was analyzed because previous publications [for 
example, the study of Myers, et al. \11\] had used brown rice as the 
standard for CO2 effects on nutrition.
    Elemental concentrations of carbon and nitrogen were determined for 
an additional 30 mg of harvest sample using an elemental analyzer 
(Vario, MAX CN, Element). Nitrogen content and carbon content were 
determined as a percentage of the dry weight of the sample. A factor of 
5.61 was used for converting nitrogen to protein concentration in rice, 
consistent with previous studies.\37\
Vitamin extraction and analysis
    Although rice does not supply the complete vitamin B complex, it is 
known to provide B1, B2, B5, B6, and B9, as well as vitamin E. These 
were extracted from dehusked, unpolished brown rice seed for the nine 
rice cultivars at the China FACE location. Brown rice (100 g) was 
homogenized to a fine powder using the previously described method; 
then, frozen sample was lyophilized using a VFD-1000 freeze dryer 
(Bilon). Lyophilization occurred in two cycles; drying at ^20 C for 48 
hours, followed by secondary drying at 0 C for 3 hours.
    For thiamine, riboflavin, pantothenic acid, and pyridoxine 
determination, 0.05 g of ascorbic acid was added to homogenized samples 
(0.5 g) as an antioxidant and then followed by 10 ml of extracting 
solution (methanol/water/phosphoric acid = 100:400:0.5, v/v/v). After 
the suspension was vortexed, it was autoclaved at 100 C for 20 min and 
then incubated under ultrasonic conditions for 30 min. The solution was 
allowed to cool to room temperature and then centrifuged at 11,945g for 
15 min. Blank controls were generated following the same process 
without rice samples. The final supernatant was filtered through a 
0.22-mm filter before high-performance liquid chromatography (HPLC)-MS 
analysis.
    Folate determination was per Blancquaert, et al.: \38\ 4 ml of 
extraction buffer was added to 0.5 g of homogenized samples, and the 
capped tube was placed at 100 C for 10 min. A tri-enzyme treatment 
with 80 ml of a-amylase (20 min), 350 ml of protease (1 hour at 37 C), 
and 250 ml of conjugase (2 hours at 37 C) was used to degrade the 
starch matrix, to release protein-bound folates, and to deconjugate 
polyglutamylated folates. To stop protease and conjugase activity, 
additional heat treatments were carried out, followed by cooling on 
ice. The resulting solution was ultrafiltrated at 11,958g for 15 min. 
The final solution was filtered through a 0.22-mm filter before 
analysis.
    Vitamin E (a-tocopherol) was extracted using an improved method, as 
described by Zhang, et al.\39\ One gram of the homogenized fine powder 
was saponified under nitrogen in a screw-capped tube with 1 ml of 
potassium hydroxide (600 g/liter), 5 ml of ethanol, 1 ml of sodium 
chloride (10 g/liter), and 2.5 ml of ethanolic pyrogallol (60 g/liter) 
added as antioxidants. Tubes were placed in a 70 C water bath and 
mixed at 5-min intervals during saponification. Following alkaline 
digestion at 70 C for 30 min, the tubes were cooled in an ice bath, 
and 5 ml of sodium chloride (10 g/liter) was added. The suspension was 
extracted twice with 8 ml of n-hexane/ethyl acetate (4:1, v/v). The 
organic layer was collected and was dried using pure nitrogen (EVA 30A, 
Polytech Co.) and then dissolved in n-hexane/methanol (20:80, v/v; 1. 
ml). A similar procedure was used to generate a blank control. The 
final solution was filtered through a 0.22-mm filter before analysis.
    HPLC-tandem MS (Thermo Finnigan TSQ) was used to quantify vitamin 
content. Column oven temperature was maintained at 25 C, and the 
autosampler was maintained at 4 C. Two separate Phenomenex Kinetex C18 
columns (4.6 mm  100 mm  2.6 mm and 4.6 mm  30 mm  5 mm) were used 
for vitamins B and E, respectively. Injection volume was 20 ml. For 
gradient elution, the mobile phase consisted of eluent A (methyl 
alcohol) and eluent B (0.1% formic acid in water), with each eluent 
pumped at a flow rate of 0.6 ml min-1. The mobile phase was 
linearly adjusted to separate the different vitamins (table S1).
    For the MS setting, source conditions were optimized for vitamin B 
as follows: ion source, electrospray ionization; spay voltage, 3500 V; 
vaporizer temperature, 400 C; capillary temperature, 350 C; sheath 
gas pressure, 50; auxillary gas pressure, 10; scan type, selected 
reaction monitoring (SRM); collision pressure, 1.0-mtorr Ar. For 
vitamin E, the source conditions were optimized as follows: ion source, 
atmospheric pressure chemical ionization; discharge current, 10 mA; 
vaporizer temperature, 300 C; capillary temperature, 350 C; sheath 
and auxiliary gas pressure, 50 and 10, respectively; scan type, SRM; 
collision pressure, 1.0-mtorr Ar (table S2). Known standards for 
vitamin B1 (thiamine hydrochloride), vitamin B2 (riboflavin), vitamin 
B5 (calcium-D-pantothenate), vitamin B6 (pyridoxine hydrochloride), 
vitamin B9 (folic acid), and vitamin E (a-tocopherol) were purchased 
from Sigma-Aldrich Co. All vitamin analyses were performed in 
duplicate. Before sample analysis, the instrument was calibrated using 
seven standards (six standards and the blank control).
Estimate of nutritional deficits
    The ten most rice-dependent countries were determined on the basis 
of the largest consumption of rice as a fraction of total available 
calories [Bangladesh, Cambodia, China, Indonesia, Lao PDR, Madagascar, 
Myanmar, Philippines, Thailand, and Vietnam (23)]. FAO food balance 
sheets (http://faostat.fao.org/beta/en/#data/FBS; food supply quantity, 
kilogram per capita per year and food supply, and kilocalorie per 
capita per day) from either 2011 (Cambodia and Lao PDR) or 2013 (all 
other countries) were used to determine rice consumption along with the 
U.S. Department of Agriculture (USDA) National Nutrient Database for 
Standard Reference data for raw brown long-grain rice (https://
ndb.nal.usda.gov/ndb/foods/show/305240?manu=&fgcd=&ds=SR) to quantify 
any CO2-induced differences in qualitative nutritional 
characteristics by individual country.
    With respect to nutritional characteristics, we used a holistic 
approach to assess changes in a number of qualitative parameters 
including protein, minerals (Fe, Ca, and Zn), and vitamins B1 
(thiamine), B2 (riboflavin), B5 (pantothenic acid), B6 (pyridoxine), B9 
(folic acid), and E (a-tocopherol). Inadequate intake of the vitamins 
and minerals assessed were associated with specific physiological 
conditions and clinical manifestations.\40\ Data for protein and 
minerals were available for all three experimental locations; however, 
vitamin analysis was only conducted for the rice lines from the China 
location. Because income level is the most important determinant of per 
capita rice consumption,\25\ and because of the wide range of per 
capita incomes of the countries assessed, any significant 
CO2-induced change in a nutritional characteristic was 
characterized with respect to GDP per capita (from 2013) for the ten 
countries examined (https://data.worldbank.org/indicator/NY.GDP.
PCAP.CD).
Statistics
    All field experiments at each location represented a completely 
randomized design with either three (China) or four (Japan) replicates. 
All measured and calculated parameters were analyzed using a two-way 
analysis of variance (ANOVA) with [CO2] and cultivar as 
fixed effects (Statview Software). Coefficient of determination (r\2\) 
was calculated for protein, mineral (Fe and Zn), and vitamin (B1, B2, 
B5, B6, B9, and E) deficits as a function of [CO2] and GDP 
per capita. Each value is the mean RSE. **P<0.01; *0.01 5P<0.05; *0.05 
5P<0.1; ns, not significant (P50.1). The figures were generated using 
Systat Software (SigmaPlot 10.0, Systat Software Inc.). No significant 
differences for [CO2] by cultivar interaction were found for 
calcium (Ca) or vitamin B6; consequently, these data are not shown 
separately. Every cultivar was grown only at a single site, which does 
not allow separation of cultivar effects from site effects. However, 
when averaged for all cultivars within a single location (Japan or 
China), no significant country interaction was observed for 
[CO2] impacts on noted reductions in protein, iron, or zinc 
(P = 0.26, 0.17, and 0.1 for protein, iron, and zinc, respectively). 
Because our purpose was to elucidate the effect of [CO2] on 
rice, but not on geographic area, cultivar effects are inclusive for 
the figures. Seasonal (yearly) variation was not significant for a 
given location and, consequently, was averaged across years for each 
FACE site. Original data are available at https://doi.org/10.6084/
m9.figshare.6179069.
Supplementary Materials
    Supplementary material for this article is available at http://
advances.sciencemag.org/cgi/content/full/4/5/eaaq1012/DC1.
    Table S1. Elution procedures for vitamin B and vitamin E.
    Table S2. Compound parameters for vitamins B1, B2, B5, B6, B9 and 
E.
    Fig. S1. As for Fig. 3, but for vitamin E (a-tocopherol) (see 
Methods for additional details).

 
 
 
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 Holbrook, R.L. Nelson, R. Norton, M.J. Ottman, V. Raboy, H. Sakai, K.A.
 Sartor, J. Schwartz, S. Seneweera, Y. Usui, S. Yoshinaga, S.S. Myers,
 Impacts of elevated atmospheric CO2 on nutrient content of important
 food crops. Sci. Data 2, 150036 (2015).
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 the expression of the endogenous folate biosynthesis genes. Plant Mol.
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39. G.-Y. Zhang, R.-R. Liu, G. Xu, P. Zhang, Y. Li, K.-X. Tang, G.-H.
 Liang, Q.-Q. Liu, Increased a-tocotrienol content in seeds of
 transgenic rice overexpressing Arabidopsis g-tocopherol
 methyltransferase. Transgenic Res. 22, 89-99 (2013).
40. A.C. Ross, B. Caballero, R.J. Cousins, K.L. Tucker, T.R. Ziegler,
 Modern Nutrition in Health and Disease (Wolters Kluwer Publishing, ed.
 11, 2012).
 

    Acknowledgments: We thank G. Kordzakhia of the U.S. Food and Drug 
Administration for his contributions. Funding: This work was supported 
by the National Basic Research Program of China (973 Program, 
2014CB954500), Natural Science Foundation of Jiangsu Province in China 
(BK20140063), Youth Innovation Promotion Association of Chinese Academy 
of Sciences (CAS; member no. 2015248), and the frontier projects for 
13th 5 year plan of CAS (Y613890000 to C.Z.). Author contributions: 
C.Z., L.H.Z., and K.K. designed the study. I.L., S.S., and K.L.E. did 
the literature review. I.L., C.Z., and L.H.Z. did the analysis with 
contributions from K.L.E., N.K.F., and A.D. J.Z., Q.J., X.X., and G.L. 
contributed data. L.H.Z. wrote the report. All authors interpreted the 
results, commented on the draft version of the report, and approved the 
submission draft. Competing interests: A.D. has received grants, 
honoraria, and consulting fees from numerous food, beverage, and 
ingredient companies and other commercial and nonprofit entities with 
an interest in diet quality and nutrient content of foods. The 
University of Washington receives research funding from public and 
private sectors. N.K.F. is the Editor-in-Chief of Nutrition Reviews, an 
International Life Sciences Institute publication, and has received 
honoraria from Monsanto and the National Dairy Council before 
employment by the USDA. The other authors declare that they have no 
other competing interests. Data and materials availability: All data 
needed to evaluate the conclusions in the paper are present in the 
paper and/or the Supplementary Materials. Original data are available 
at https://doi.org/10.6084/m9.figshare.6179069.

    Submitted 1 October 2017
    Accepted 6 April 2018
    Published 23 May 2018
    10.1126/sciadv.aaq1012
                                 ______
                                 
  Submitted Reports by Hon. David Scott, a Representative in Congress 
                             from Georgia *
---------------------------------------------------------------------------
    * Editor's note: the reports listed are retained in Committee file.

  1.  Vose, J.M., D.L. Peterson, G.M. Domke, C.J. Fettig, L.A. Joyce, 
            R.E. Keane, C.H. Luce, J.P. Prestemon, L.E. Band, J.S. 
            Clark, N.E. Cooley, A. D'Amato, and J.E. Halofsky, 2018, 
            Forests. In Impacts, Risks, and Adaptation in the United 
            States: Fourth National Climate Assessment, Volume II 
            [Reidmiller, D.R., C.W. Avery, D.R. Easterling, K.E. 
            Kunkel, K.L.M. Lewis, T.K. Maycock, and B.C. Stewart 
            (eds.)]. U.S. Global Change Research Program, Washington, 
---------------------------------------------------------------------------
            D.C., USA, pp. 232-267. doi: 10.7930/NCA4.2018.CH6.

  2.  Gowda, P., J.L. Steiner, C. Olson, M. Boggess, T. Farrigan, and 
            M.A. Grusak, 2018, Agriculture and Rural Communities. In 
            Impacts, Risks, and Adaptation in the United States: Fourth 
            National Climate Assessment, Volume II [Reidmiller, D.R., 
            C.W. Avery, D.R. Easterling, K.E. Kunkel, K.L.M. Lewis, 
            T.K. Maycock, and B.C. Stewart (eds.)]. U.S. Global Change 
            Research Program, Washington, D.C., USA, pp. 391-437. doi: 
            10.7930/NCA4.2018.CH10.

  3.  Crane-Droesch, A., Marshall, E., Rosch, S., Riddle, A., Cooper, 
            J., and Wallander, S., July 2019, Climate Change and 
            Agricultural Risk Management Into the 21st Century, ERR-
            266, U.S. Department of Agriculture, Economic Research 
            Service, https://www.ers.usda.gov/publications/pub-details/
            ?pubid=93546.

  4.  Key, N, Sneeringer, S., and Marquardt, D, September 2014, Climate 
            Change, Heat Stress, and U.S. Dairy Production, ERR-175, 
            U.S. Department of Agriculture, Economic Research Service, 
            https://www.ers.usda.gov/publications/pub-details/
            ?pubid=45282.

  5.  Marshall, E., Aillery, M., Malcolm, S., Williams, R., November 
            2015, Climate Change, Water Scarcity, and Adaptation in the 
            U.S. Fieldcrop Sector, ERR-201, U.S. Department of 
            Agriculture, Economic Research Service, https://
            www.ers.usda.gov/publications/pub-details/?pubid=45496.

  6.  Vose, J.M., Peterson, D.L., and Patel-Weynand, T., December 2012, 
            Effects of Climatic Variability and Change on Forest 
            Ecosystems: A Comprehensive Science Synthesis for the U.S. 
            Forest Sector, Gen. Tech. Rep. PNW-GTR-870. Portland, OR: 
            U.S. Department of Agriculture, Forest Service, Pacific 
            Northwest Research Station, https://www.srs.fs.usda.gov/
            pubs/42610.

  7.  Litterman, B., Anderson, C., Bullard, N., Caldecott, B., Cheung, 
            M., Colas, J., Coviello, R., Davidson, P., Dukes, J., 
            Duteil, H., Eastwood, A., Eubank, E., Figueroa, N., 
            Goolgasian, C., Hartmann, J., Jones, D., Keenan, J., 
            Keohane, N., Lubber, M., Winkler, J., 2020, Managing 
            Climate Risk in the U.S. Financial System, U.S. Commodity 
            Futures Trading Commission, Market Risk Advisory Committee, 
            https://www.cftc.gov/sites/default/files/2020-09/9-9-20 
            Report of the Subcommittee on Climate-Related Market 
            Risk_Managing Climate Risk in the U.S. Financial System for 
            posting.pdf.

  8.  Brown, M.E., J.M. Antle, P. Backlund, E.R. Carr, W.E. Easterling, 
            M.K. Walsh, C. Ammann, W. Attavanich, C.B. Barrett, M.F. 
            Bellemare, V. Dancheck, C. Funk, K. Grace, J.S.I. Ingram, 
            H. Jiang, H. Maletta, T. Mata, A. Murray, M. Ngugi, D. 
            Ojima, B. O'Neill, and C. Tebaldi,. 2015, Climate Change, 
            Global Food Security, and the U.S. Food System, U.S. 
            Department of Agriculture, Office of the Chief Economist, 
            http://www.usda.gov/oce/climate_change/
            FoodSecurity2015Assessment/FullAssessment.pdf.

  9.  Walsh, M.K., Backlund, P., Buja, L., DeGaetano, A., Melnick, R., 
            Prokopy, L., Takle, E., Todey, D., Ziska, L., 2020, Climate 
            Indicators for Agriculture, USDA Technical Bulletin 1953. 
            Washington, D.C., https://www.usda.gov/sites/default/files/
            documents/climate_indicators_for_agriculture.pdf.

  10. McKenzie, D., Heinsch, F.A., Heilman, W.E., January 2011, 
            Wildland Fire and Climate Change, U.S. Department of 
            Agriculture, Forest Service, Climate Change Resource 
            Center. www.fs.usda.gov/ccrc/topics/wildfire, accessed 
            March 2, 2021.
                                 ______
                                 
  Submitted Letters by Hon. David Scott, a Representative in Congress 
                              from Georgia
                                Letter 1
on behalf of chad hanson, ph.d., chief scientist and director; jennifer 
       mamola, d.c. forest protection advocate, john muir project
March 12, 2021

 
 
 
Hon. David Scott,                    Hon. Glenn Thompson,
Chairman,                            Ranking Minority Member,
House Committee on Agriculture,      House Committee on Agriculture,
Washington, D.C.;                    Washington, D.C.
 

    Re: House Agriculture Hearing on Climate Change and the U.S. 
            Agriculture & Forestry Sectors

    Dear Mr. Chairman, Ranking Member, Members and Staff;

    Last month we virtually attended your February 25th Agriculture 
Hearing on Climate Change and the U.S. Agriculture and Forestry 
Sectors. The majority of the focus was on how best to address issues 
within the agriculture sector which should be applauded as now more 
than ever we need to truly focus on those communities that feed us. 
Unfortunately, the brief mention of forests was often undermined by a 
demonization of nature, with a focus on logging under the guise of 
``fuel reduction'',which releases more carbon into the atmosphere and 
often makes fires burn more intensely.
    Unfortunately, at times the focus of the hearing veered away from 
solutions that would benefit society, the environment, and help us to 
solve the climate crisis. We are writing this letter to hopefully bring 
some balance to the testimony, verbal and written, that was presented 
and to address the problematic underlying narrative which appears to be 
shifting Members' attention away from actions that will actually make a 
difference for people and the planet.

  1.  Vegetation is not driving wildfires: our forests aren't 
            overstocked

        Since the King Fire (see map below) was referenced and 
            vegetation was blamed, it's probably one of the best 
            examples of when the winds are blowing hard and the fire 
            starts a major run, thinning or any other treatment 
            (including prescribed fire) just doesn't prevent or stop 
            fire. That fire burned almost exclusively at high severity 
            in one particular portion of the fire on a huge run during 
            a single day that was all due to a crazy localized wind 
            event. That single day accounted for almost all of the high 
            severity burned area in that fire, due to high wind.
Figure 1


          (a) 2018, Coen, et al., Deconstructing the King megafire;  
        (b) https://climate.nasa.gov/news/2771/local-winds-play-a-key-
        role-in-some-megafires/.
          Editor's note: entries annotated with  are retained in 
        Committee file.

        Meaning, the number one driver of fire behavior and extent is 
            the climate, specifically high temperatures, extreme wind 
            speeds and single digit humidity. Climate change is making 
            these conditions more prevalent, more often. It is also 
            important to appreciate the fact that we do not currently 
            have an excess of fire in forests. We have always had fires 
            in the West and always will, and there is wide agreement 
            among scientists that we currently have less mixed-
            intensity fire in our forests than we did historically, 
            before fire suppression and, while annual acres burned is 
            incrementally getting slightly closer to historical levels, 
            in part due to climate change, fire intensity in forests is 
            not increasing.\1\ The real issue is that, increasingly, 
            climate and weather factors drive fires that humans are not 
            able to suppress. Fires that cannot be suppressed, 
            especially when they are started by human ignitions or 
            infrastructure, have the potential to burn into and affect 
            communities which have sprawled over time into our fire-
            adapted ecosystems.
---------------------------------------------------------------------------
    \1\ (a) DellaSala, D.A., and C.T. Hanson (Editors). 2015. The 
ecological importance of mixed-severity fires: nature's phoenix. 
Elsevier Inc., Waltham, MA, USA; (b) Keyser, A.; Westerling, A. Climate 
drives inter-annual variability in probability of high severity fire 
occurrence in the western United States. Environ. Res. Lett. 2017, 12, 
65003.
---------------------------------------------------------------------------
        There are several ways that we know it is climate conditions, 
            rather than the vegetation, that is driving fire behavior. 
            First, and most informative are the field-based studies 
            that have looked at the effect, if any, that decades of 
            successful fire suppression has had on fire intensity. 
            Specifically, seven studies have investigated whether areas 
            that have not experienced fire in a very long time (i.e., 
            areas that have had the chance for vegetation to grow 
            unimpeded for a century or more) burn at higher intensity 
            than areas which have experienced fire more recently. Three 
            of the seven studies found unequivocally that areas that 
            have not burned in a very long time do not burn at higher 
            intensities than areas that have burned in recent decades, 
            three of the remaining four studies found that the most 
            long-unburned forests (the densest forests) burned at lower 
            intensities than other forests, and the final of the seven 
            studies speculated that long-unburned forests would burn 
            slightly more intensely but would still be dominated by 
            lower-intensity fire effects (and this study, unlike the 
            other six, involved a theoretical model, and its conclusion 
            was not based on actual fire data).\2\
---------------------------------------------------------------------------
    \2\ (a) Miller J.D., Skinner C.N., Safford H.D., Knapp E.E., 
Ramirez C.M. 2012a. Trends and causes of severity, size, and number of 
fires in northwestern California, USA. Ecological Applications 22, 
184-203; (b) Odion, D.C., E.J. Frost, J.R. Strittholt, H. Jiang, D.A. 
DellaSala, and M.A. Moritz. 2004. Patterns of fire severity and forest 
conditions in the Klamath Mountains, northwestern California. 
Conservation Biology 18: 927-936; (c) Odion, D.C., and C.T. Hanson. 
2006. Fire severity in conifer forests of the Sierra Nevada, 
California. Ecosystems 9: 1177-1189; (d) Odion, D.C., and C.T. Hanson. 
2008. Fire severity in the Sierra Nevada revisited: conclusions robust 
to further analysis. Ecosystems 11: 12-15; (e) Odion, D.C., M.A. 
Moritz, and D.A. DellaSala. 2010. Alternative community states 
maintained by fire in the Klamath Mountains, USA. Journal of Ecology, 
doi: 10.1111/j.1365-2745.2009.01597.x; (f) van Wagtendonk, J.W., K.A. 
van Wagtendonk, and A.E. Thode. 2012. Factors associated with the 
severity of intersecting fires in Yosemite National Park, California, 
USA. Fire Ecology 8: 11-32; (g) Steel, et al. 2015. Ecosphere 8: 
Article 8.
---------------------------------------------------------------------------
        Next we have empirical research which has investigated whether 
            the number of dead trees in a given area drives fire 
            behavior. The most comprehensive scientific studies 
            (including one prepared by NASA) found that forests with 
            more dead trees burn the same as other forests or burn at 
            lower intensities.\3\ While it may seem counterintuitive, 
            soon after trees die (whether from drought or beetle 
            activity), they shed their needles and small branches which 
            fall to the ground and decay into soil and there is no real 
            mechanism to carry flames.
---------------------------------------------------------------------------
    \3\ (a) Hart, S.J., T. Schoennagel, T.T. Veblen, and T.B. Chapman. 
2015. Area burned in the western United States is unaffected by recent 
mountain pine beetle outbreaks. Proceedings of the National Academy of 
Sciences of the USA 112: 4375-4380; (b) Meigs, G.W., H.S.J. Zald, J.L. 
Campbell, W.S. Keeton, and R.E. Kennedy. 2016. Do insect outbreaks 
reduce the severity of subsequent forest fires?  Environmental 
Research Letters 11: 045008.
---------------------------------------------------------------------------
        Importantly, our forests currently have significantly less tree 
            biomass in them than they did historically, due to decades 
            of logging. Claims that our forests are ``overstocked'' are 
            quite simply misleading.\4\
---------------------------------------------------------------------------
    \4\ (a) McIntyre, P.J., et al. 2015. Twentieth-century shifts in 
forest structure in California: Denser forests, smaller trees, and 
increased dominance of oaks. Proceedings of the National Academy of 
Sciences of the United States of America 112: 1458-1463; (b) Erb, K.H., 
et al. 2018. Unexpectedly large impact of forest management and grazing 
on global vegetation biomass. Nature 553: 73-76.

  2.  Since vegetation is not driving wildfires, vegetation management, 
            thinning and other forms of logging, and prescribed burning 
---------------------------------------------------------------------------
            are not necessary

        Climate and weather are driving wildfire behavior, but to the 
            extent that density of vegetation has an influence, it is 
            the opposite of what many assume. Numerous studies have 
            investigated this issue, measuring forest density directly 
            and how it relates to fire behavior. These studies, similar 
            to the ones referenced above, also found that the densest 
            mature forests generally burn at lower intensities. This is 
            because denser forests have more trees, which provide more 
            shade, which keep conditions cooler and more moist. Whereas 
            forests with fewer trees, often due to logging/mechanical-
            thinning, burned at higher intensities. This is because 
            logging reduces the cooling shade of the forest canopy, 
            creating hotter, drier conditions, while also removing 
            trees which have a buffering effect on wind speeds, 
            eliminating the forests ability to slow fire spread. Far 
            from being a ``fire'' solution, logging/thinning does not 
            stop fires, and fires often move more rapidly through these 
            areas. Further, the most comprehensive scientific study 
            ever conducted on this question found that forests with the 
            most logging a.k.a ``forest management'' burn the most 
            intensely, not the least.\5\
---------------------------------------------------------------------------
    \5\ (a) Bradley, C.M. C.T. Hanson, and D.A. DellaSala. 2016. Does 
increased forest protection correspond to higher fire severity in 
frequent-fire forests of the western USA?  Ecosphere 7: article 
e01492; (b) Zald, H.S.J., and C.J. Dunn. 2018. Severe fire weather and 
intensive forest management increase fire severity in a multi-ownership 
landscape. Ecological Applications 28: 1068-1080; (c) Meigs, G., D. 
Donato, J. Campbell, J. Martin, and B. Law. 2009. Forest fire impacts 
on carbon uptake, storage, and emission: The role of burn severity in 
the Eastern Cascades, Oregon. Ecosystems 12: 1246-1267; (d) Cruz, 
M.G., M.E. Alexander, and J.E. Dam. 2014. Using modeled surface and 
crown fire behavior characteristics to evaluate fuel treatment 
effectiveness: a caution. Forest Science 60: 1000-1004; (e) DellaSala, 
D.A,, C.T. Hanson. 2019. Are wildland fires increasing large patches of 
complex early seral forest habitat?  Diversity 11: Article 157.
---------------------------------------------------------------------------
        Prescribed fire does not stop wildland fires either. In fact, 
            wildland fires can burn again even within as little as 1 or 
            2 year after a prescribed fire, as we just saw in Australia 
            (the bushfires burned right through the largest prescribed 
            burn in the nation's history, which was conducted in 2017). 
            Historically, forests burned every few decades, not every 2 
            years.\6\ If we attempt to ``fireproof'' the landscape with 
            prescribed fire, we would be imposing far more fire than is 
            natural on ecosystems, impacting biodiversity and damaging 
            soils and forest productivity all while creating vastly 
            more smoke than currently occurs with wildland fires--and 
            it would not stop wildland fires.
---------------------------------------------------------------------------
    \6\ DellaSala, D.A., and C.T. Hanson (Editors). 2015. The 
ecological importance of mixed-severity fires: nature's phoenix. 
Elsevier Inc., Waltham, MA, USA.
---------------------------------------------------------------------------
        Pursuing a ``forest management'' approach to fire fundamentally 
            ignores and denies that climate is driving fire behavior. 
            These activities will not solve our community protection 
            problem, or assist with climate adaptation and will 
            exacerbate rather than mitigate the climate and extinction 
            crises we currently face. Not to mention the colossal 
            amounts of money that is burned in the backcountry. A 
            witness even stated they'd love to see more money spent, 
            yet all that would do is emit even more carbon into the 
            atmosphere while communities continue to be ill-prepared 
            for the inevitable fire season.

  3.  To protect communities, we must focus on communities

        Fires are ultimately weather driven events, similar to 
            tornadoes and hurricanes. Accepting this will enable us to 
            do what is necessary to focus our efforts on community 
            protection, resilience, disaster preparedness and 
            mitigation. Outside of putting resources into stopping 
            human ignitions via more patrols during high fire weather 
            and educating the public about fire-safe activities, once a 
            fire starts under extreme weather conditions it is going to 
            burn.
        According to the scientific research the only effective way to 
            protect homes from wildland fire is to focus on making the 
            homes themselves more fire-safe, and to conduct annual 
            defensible space pruning within 100 of homes. Beyond 100 
            from houses, there is no additional benefit to home 
            protection from vegetation management.\7\ Congressional 
            resources should be put into such efforts, similar to a 
            bill from the 116th Congress that took a first step in this 
            direction S. 2882/ H.R. 5091 Wildfire Defense Act.
---------------------------------------------------------------------------
    \7\ Syphard, A.D., T.J. Brennan, and J.E. Keeley. 2014. The role of 
defensible space for residential structure protection during 
wildfires. Intl. J. Wildland Fire 23: 1165-1175.
---------------------------------------------------------------------------
        Because we cannot suppress weather driven fires, we cannot stop 
            the smoke that they create. What we can and must do is 
            promote measures that will keep people safer and help 
            communities adapt: by devoting resources to help create 
            better fire and smoke warning and evacuation systems; 
            develop programs which help homeowners in need with air 
            filters for smoke, and access to appropriate respiratory 
            masks (as mentioned at the hearing); create smoke relief 
            centers for sensitive groups; have options for emergency 
            housing; daycare; rideshares to work and always ensure that 
            these services are available to everyone, regardless of 
            income.
        Unfortunately, employing forest management, by way of logging 
            and removal of vegetation from our forests, as a ``fire 
            fix'' diverts scarce resources away from measures that 
            would actually make people safer, and it gives communities 
            a dangerous and false sense of security because such 
            actions will not stop fires or alter weather driven fire 
            behavior. We saw a tragic example of this in the Camp fire 
            of 2018, which burned so rapidly through several thousand 
            acres of heavily managed forestland (which had been post-
            fire clearcut and/or thinned) during the first 6 hours of 
            the fire that people within the towns of Paradise and 
            Concow had very little time to evacuate, with tragic 
            results. So called fuels reduction and post-fire 
            ``restoration'' did not save these towns from this weather 
            driven fire, it made the tragedy worse.\8\
---------------------------------------------------------------------------
    \8\ https://johnmuirproject.org/2019/01/logging-didnt-stop-the-
camp-fire/.

  4.  Forests, as they exist right now, are a climate solution not a 
---------------------------------------------------------------------------
            climate problem

        Our forests are currently substantial carbon sinks, absorbing 
            more carbon than they emit, but they could absorb much more 
            carbon than they currently do, if they were protected from 
            logging. Logging is the real source of carbon emissions 
            from forests. In U.S. forests, for example, logging (of all 
            types, thinning/post-fire/clearcutting/group-selection, 
            etc.) emits ten times more carbon than is emitted from 
            wildland fire and tree mortality from drought and native 
            bark beetles combined. Dead trees and downed logs decay 
            extremely slowly (decades to a century or more), and 
            eventually return their nutrients to the soil, which helps 
            maintain the productivity and carbon sequestration capacity 
            of the forest.\9\
---------------------------------------------------------------------------
    \9\ (a) Harris, N.L., et al. 2016. Attribution of net carbon change 
by disturbance type across forest lands of the conterminous United 
States. Carbon Balance Management 11: Article 24; (b) Meigs, G., et 
al. 2009. Forest fire impacts on carbon uptake, storage, and emission: 
The role of burn severity in the Eastern Cascades, Oregon. Ecosystems 
12: 1246-1267; (c) Meigs, G.W., H.S.J. Zald, J.L. Campbell, W.S. 
Keeton, and R.E. Kennedy. 2016. Do insect outbreaks reduce the severity 
of subsequent forest fires?  Environmental Research Letters 11: 
045008.
---------------------------------------------------------------------------
        Wildland fires, including large mixed-severity fires, only 
            consume about 1% to 2% of the biomass of trees in the 
            forest, and therefore only release this small portion of 
            the carbon stored in trees into the atmosphere. We know 
            this from field-based studies of actual fires in actual 
            forests. The problem is that Federal and state agencies use 
            theoretical models to estimate carbon emissions from forest 
            fires and dead trees, but the models wildly exaggerate 
            carbon emissions from decay and fire. For example, in the 
            257,000 acre Rim fire of 2013, field-based data determined 
            that only \1/10\ of 1% of the carbon in trees was actually 
            consumed in typical fire conditions, whereas the 
            theoretical models falsely assume levels of consumption 
            that are often dozens, or hundreds, of times higher than 
            this.\10\
---------------------------------------------------------------------------
    \10\ Stenzel, J.E., et al. 2019. Fixing a snag in carbon emissions 
estimates from wildfires. Global Change Biology 25: 3985-3994.

  5.  The proposals supported by the witnesses will harm our 
---------------------------------------------------------------------------
            environment, biodiversity and the climate

        There was discussion and written testimony at this hearing of 
            logging as an answer to the ``fire'' problem. But we 
            actually don't have a fire problem in our forest 
            ecosystems. We have substantially less mixed-intensity fire 
            now than we had historically, before fire suppression. In 
            addition, wildland fires, especially the large fires that 
            burn at mixed-intensity, transform forest ecosystems but do 
            not destroy them. In fact these fires create natural 
            heterogeneity across vast areas, rejuvenating wildlife 
            habitat to such a degree that the biodiversity in mature 
            forests that experience high-intensity fire is similar to 
            levels of biodiversity found in unlogged old-growth 
            forests, and the same is true for areas which have 
            experienced drought and beetle related tree mortality.\11\ 
            In addition, forests are naturally regenerating even in the 
            largest high-intensity fire patches.
---------------------------------------------------------------------------
    \11\ DellaSala, D.A., and C.T. Hanson (Editors). 2015. The 
ecological importance of mixed-severity fires: nature's phoenix. 
Elsevier Inc., Waltham, MA, USA.
---------------------------------------------------------------------------
        While we do not have a fire in our forests problem, we most 
            certainly do have a problem with fire affecting our 
            communities and a climate change problem. We therefore need 
            solutions to protect and adapt communities and to combat 
            climate change. Logging, whether you call it thinning, 
            vegetation management, forest management or biomass 
            removal, will remedy neither of these problems and actually 
            makes things worse. It is simply another part of the carbon 
            economy. Since no witness at the hearing addressed the 
            carbon cost of logging we thought we would share some 
            statistics here. Due to its industrial nature, 
            approximately 81% of the carbon in trees that are logged 
            quickly ends up in the atmosphere, with only 19% ending up 
            being stored in wood products. Logging also removes 
            nutrients from forests and compacts soils, reducing the 
            overall productivity and function of the forest ecosystem 
            as well as its carbon sequestration and storage 
            capacity.\13\ Notably, numerous studies find that logging 
            conducted under the guise of ``thinning'', ``fuels 
            reduction'' and fire management actually causes a large net 
            loss of forest carbon storage and a substantial net 
            increase in carbon emissions relative to wildland fire 
            alone.\14\
---------------------------------------------------------------------------
    Editor's note: the letter submitted by the John Muir project does 
not have a footnote reference for footnote no. 12. It has been 
reproduced, as submitted, herein. Below is footnote 12 that was 
included at the end of the letter.
    \12\ Hudiburg, T.W., Beverly E. Law, William R. Moomaw, Mark E. 
Harmon, and Jeffrey E. Stenzel. 2019. Meeting GHG reduction targets 
requires accounting for all forest sector emissions. Environmental 
Research Letters 14: Article 095005.
    \13\ (a) Walmsley, J.D., et al. 2009. Whole tree harvesting can 
reduce second rotation forest productivity. Forest Ecology and 
Management 257: 1104-1111; (b) Elliot, W.J., et al. 1996. The effects 
of forest management on erosion and soil productivity. Symposium on 
Soil Quality and Erosion Interaction. July 7, 1996, Keystone, CO.
    \14\ (a) Campbell, J.L., M.E. Harmon, and S.R. Mitchell. 2012. Can 
fuel-reduction treatments really increase forest carbon storage in the 
western U.S. by reducing future fire emissions?  Frontiers in Ecology 
and Environment 10: 83-90; (b) Hudiburg, T.W., et al. 2013. Interactive 
effects of environmental change and management strategies on regional 
forest carbon emissions. Environmental Science and Technology 47: 
13132-13140.

    We hope that you have found the above information helpful and we 
urge you to consider the foregoing, and to reject false climate 
solutions that would make climate change worse and increase risks to 
vulnerable communities. We need to increase protection of our forests 
from logging, and focus resources on directly protecting and helping 
vulnerable communities. The recommendations made by numerous speakers 
at the hearing, and the comments made by some Members, would take us in 
the wrong direction. We would be happy to answer questions or provide 
additional information, so please feel free to contact us if you would 
like to have a dialogue on these issues.
            Sincerely,
            
            

 
 
 
Chad Hanson, Ph.D.,                  Jennifer Mamola,
Chief Scientist and Director,        D.C. Forest Protection Advocate,
John Muir Project;                   John Muir Project.
 

                                Letter 2
 on behalf of john linder, president, national corn growers association
March 5, 2021

    Hon. David Scott,
    Chairman,
    House Committee on Agriculture,
    Washington, D.C.;

    Hon. Glenn Thompson,
    Ranking Minority Member,
    House Committee on Agriculture,
    Washington, D.C.

    Dear Chairman Scott and Ranking Member Thompson:

    On behalf of the National Corn Growers Association (NCGA), we 
appreciate the opportunity to submit this statement outlining corn 
grower priorities on policies related to climate change. We request 
this statement be included in the record for the February 25, 2021 
hearing of the House Agriculture Committee, ``Climate Change and the 
U.S. Agriculture and Forestry Sectors.''
    Founded in 1957, NCGA represents nearly 40,000 dues-paying corn 
farmers nationwide and the interests of more than 300,000 growers who 
contribute through corn checkoff programs in their states. NCGA and its 
48 affiliated state organizations work together to create and increase 
opportunities for corn growers. Corn provides a nutritious and 
sustainable feed for the global livestock sector, supplies the world 
with renewable fuel and replaces petroleum and other non-renewable 
ingredients in a variety of industrial and consumer products.
    NCGA supports the agriculture sector's opportunity to contribute to 
carbon reduction based on carbon offsets and carbon sequestration 
through crop production, as well as through further decarbonization of 
transportation fuels through increased use of renewable fuels. Further, 
NCGA supports market-based, voluntary opportunities for farmers to 
provide carbon reduction benefits.
    A changing climate poses a unique threat to agriculture because 
weather has a direct impact on farm production and profitability. With 
weather likely to become even more unpredictable, a reliable and 
consistent food supply for a growing population is more important than 
ever before. Building upon the strong foundation of voluntary 
stewardship investments andsustainable farming practices, climate 
policy should support research and innovation needed todevelop new 
technologies that will help farmers respond to climate change and 
continuereducing greenhouse gas emissions.
Soil Carbon Sequestration Potential
    Corn as a crop can serve as a carbon sink. As a photo-synthetically 
superior C4 plant, corn has an extraordinary ability to 
sequester carbon and move fertilizer nutrients back to the surface for 
plant growth rather than into ground water. Corn's extensive, deep root 
system makes it one of the few plants with this important capability to 
make crop production more sustainable.
    High-yield corn--combined with the steady adoption of best 
practices such as reductions in tillage intensity--is sequestering 
carbon from the atmosphere into the soil. This sequestration is 
increasing soil carbon levels and reducing atmospheric carbon. 
According to the Journal of Soil and Water Conservation, the potential 
to sequester atmospheric carbon in soil is greatest on lands currently 
used for annual crops where there is potential to sequester carbon in 
the soil at an annual growth rate of 0.4 percent each year. The results 
of tracking soil organic carbon advancements on select USDA-specified 
agricultural land areas is estimated to have sequestered an estimated 
309 metric tons of CO2-equivalent in less than a decade.
    Research increasingly demonstrates the ability to account for the 
direct effects corn production has on soil carbon stocks, whether as 
part of climate change policy, carbon markets that support agriculture 
or in ethanol lifecycle assessment (LCA) accounting such as the 
Department of Energy's Argonne National Lab Greenhouse gases, Regulated 
Emissions, and Energy use in Transportation (GREET) model.
NCGA's Soil Health Partnership and Climate
    Soil health practices and management systems hold the potential to 
mitigate climate change but further research is needed to fully 
understand the benefits of soil health practices. There is a major gap 
in understanding how soil health practices impact soil health, water 
quality, air quality and greenhouse gas (GHG) emissions.
    NCGA is working to bridge this gap through its flagship 
sustainability program, the Soil Health Partnership (SHP). SHP's 
mission is to utilize science and data to partner with farmers who are 
adopting agricultural conservation practices that improve economic and 
environmental sustainability. The partnership has more than 220 working 
farms enrolled in 15 states. It is the only farmer-led effort that 
focuses on supporting farmers as they experiment with new conservation 
practices like cover crops, reduced or no tillage and nutrient 
management with the benefit of support from SHP expert partners. SHP 
works with farmers to achieve the goal of broader adoption of 
conservation practices and understanding how varying practices affect 
the environment.
    SHP is focused on soil health improvements as the key 
transformation that facilitates many subsequent improvements ranging 
from increased productivity, increased resilience to weather changes, 
improved water quality, reduced soil erosion and increased carbon 
sequestration. The soil health indicators measured are both 
quantitative and qualitative to gauge the intermediate and long-term 
impacts of these changes.
    Farmers enroll to run research trials on their active farms, with 
data collected on 165 variables over 5 years. As a result, SHP has one 
of the most unique data sets in the country that combines information 
from diverse farms across 15 states, multiple years, and many soil 
types to allow for an analysis of trends. SHP will soon be able to 
analyze the impact of various conservation practices on the 
environment, coupled with an understanding of the management decisions 
made to put those practices in place and how they impact farmers 
economically.
    Farmers are making major impacts on the environment in ways that 
have been historically underestimated. SHP's initial analyses show 
increases in soil organic matter of about \1/4\ of 1 percent over the 
first 2-3 years in the program, which suggests improved soil water 
holding capacity and possibly carbon storage over time. Currently, 
there is not sufficient longitudinal, diverse data to fully understand 
the long-term impacts of various conservation practices on climate 
outcomes, e.g., GHG emissions, but through SHP's continued work, we 
will be able to understand the impact and better target our resources 
and energy to benefit farmers and the environment.
    In addition to measuring changes in soil organic matter over time, 
SHP is also part of a multiyear, multi-partner Conservation Innovation 
Grant through USDA NRCS to create a carbon accounting and insetting 
framework that would enable companies along the supply chain to 
encourage farmers to adopt conservation practices such as reduced 
tillage and cover crops to sequester carbon in the soil. The framework 
employs the DeNitrification-DeComposition (DNDC) model to model GHG 
impacts from on-farm practice changes and uses the Operational Tillage 
Informational System (OpTIS) as a low-cost, low-touch verification tool 
for the framework.
Biotechnology, Crop Protection Tools and Climate Change
    Prior to the introduction of transgenic seeds tolerant to broad-
spectrum pesticides, farmers were forced to rely on tillage to manage 
weeds in their fields. When the first transgenic, or GMO, crops became 
commercially available, farmers were no longer forced to rely solely on 
tillage for weed control.
    Transgenic seeds that contain a tolerance to certain pesticides 
could be used without the need for tillage because those crop 
protection products could be applied over the top of the seeds without 
damaging them. With this new option in place, farmers replace intense 
tillage previously required for control with conservation tillage 
practices. Conservation tillage, defined as tillage systems leaving at 
least 30 percent of the soil surface covered by crop residue at crop 
planting, has now been widely adopted by farmers around the country. 
The use of these practices substantially reduces soil erosion. GMOs 
also reduce the amount of pesticides that need to be sprayed. Over the 
last 20 years, this technology has reduced pesticide applications by 
8.2 percent and helped increase crop yields by 22 percent.
    Maintaining access to innovative and effective products, including 
transgenic seeds and pesticides, is important for enabling agriculture 
to be part of the solution for global climate challenges. First, 
farmers using conservation tillage practices make fewer trips over 
their field over the course of a growing season, thus reducing energy 
consumption. Second, plants are known consumers of carbon dioxide, 
pulling it out of the atmosphere and storing it in the soil through 
their roots. Tillage breaks up the soil carbon which is then released 
back into the atmosphere. If farmers must revert to using heavy tillage 
to control weeds, agriculture will likely decrease its ability to 
capture and store carbon in the soil and, therefore, decrease its 
ability to positively address climate change.
Decarbonization From Renewable Fuels
    NCGA supports the Renewable Fuel Standard (RFS), the only Federal 
statutory GHG reduction requirement. The RFS provides low carbon 
biofuels access into the closed transportation fuel market. Recent EPA 
administration of the RFS, with extensive waivers for refineries for 
biofuels blending, reduces renewable fuel demand and the emissions 
reductions provided by biofuels. NCGA supports upholding the integrity 
of the RFS to further reduce emissions in the transportation sector. 
The RFS has exceeded projections and resulted in cumulative carbon 
reduction savings of 980 million metric tons since 2007, due to greater 
than expected savings from conventional ethanol and despite lower than 
expected production of next generation fuels.
    The transportation sector accounts for nearly a third of the 
nation's GHG emissions. Near-term achievable emissions reductions from 
this sector should be prioritized by increasing use of renewable fuels. 
Federal LCA models show that conventional ethanol's carbon footprint is 
shrinking, allowing renewable fuel use to contribute to greater 
decarbonization of transportation fuel.
    The RFS requires renewable fuels to meet lifecycle GHG emission 
reduction thresholds. Models used to predict RFS impacts in 2010 
projected that use of conventional ethanol would reduce GHG emissions 
by 21 percent compared to gasoline by 2022. However, updated analysis, 
based on actual corn and ethanol production, shows much greater GHG 
reductions than projected. As a result, corn-based ethanol is 
delivering far more GHG reductions today than anticipated in the RFS.
    Ethanol's carbon footprint is shrinking due to advances in both 
corn and ethanol production. A 2018 USDA study shows that ethanol 
results in 39 to 43 percent fewer GHG emissions than gasoline. Building 
on this progress, additional improvements on farms and in ethanol 
production supported by expanding markets for low carbon fuels could 
result in ethanol with up to 70 percent fewer GHG emissions than 
gasoline, according to USDA's analysis.
    The GREET model measures lifecycle emissions of transportation 
fuels and is considered the ``gold standard'' in lifecycle analysis. 
Updated annually, GREET shows steady improvement in corn ethanol's 
lifecycle GHG profile, with corn-based ethanol's carbon intensity (CI) 
currently about 41 percent below that of baseline gasoline, following 
steady improvement since 2010, when GREET showed ethanol's CI about 19 
percent below that of gasoline.
    Furthermore, according to California Air Resources Board (CARB) 
data, the CI of ethanol under the state's Low Carbon Fuel Standard 
(LCFS) is more than 30 percent lower today than it was in 2011 and at 
least 40 percent lower than the CI of gasoline. These significant 
improvements in ethanol's carbon intensity are the result of 
advancements and wider adoption of more efficient farming practices, 
improved efficiency in ethanol production and increased crop 
productivity that efficiently uses existing crop land and is not 
producing land cover change. For example, Argonne's recent updates to 
the GREET model incorporate the growing adoption of reduced tillage and 
no-tillage practices into the LCA for ethanol.
    NCGA strongly supports using Argonne's GREET model as the basis for 
updated and accurate measurement of the decarbonization conventional 
ethanol provides in the transportation sector. With the benefit of 
real-world data on crop and ethanol production through the expansion of 
renewable fuels production since 2005, LCA should be based on 
experience, not estimates or projections. These updates to the LCA show 
that corn-based ethanol is far exceeding the GHG emissions reductions 
required and expected under the RFS.
    Although electric vehicles have gained market penetration, liquid 
fuel powered vehicles will remain the dominant vehicle type for the 
foreseeable future. According to U.S. Energy Information 
Administration's 2020 Energy Outlook, gasoline and flex-fuel vehicles 
will make up 81 percent of vehicle sales in 2050. With continued use of 
liquid fuel vehicles, continued decarbonization can be accomplished 
through greater use of biofuels such as ethanol. NCGA views biofuels 
such as ethanol as a key part of the solution for further decarbonizing 
the transportation sector.
Low Carbon Octane Standard for Fuel Efficiency and Decarbonization
    Matching new engine technologies with improved transportation fuels 
would make vehicles more fuel efficient and reduce emissions further. 
Establishing a Low Carbon Octane Standard (LCOS) for light duty vehicle 
fuel would reduce GHG emissions, improve fuel efficiency, improve air 
quality and further diversify the fuel supply--all while maintaining 
fuel and vehicle affordability and choice for drivers.
    In the 116th Congress, Representative Cheri Bustos, an Agriculture 
Committee Member, introduced the Next Generation Fuels Act, legislation 
to establish a low carbon, high octane standard for fuel. This 
legislation would establish a minimum fuel octane standard of 98 
Research Octane Number, or RON, for motor gasoline paired with a 
requirement that sources of additional octane result in at least 30 
percent fewer GHG emissions than baseline gasoline and removal of 
barriers to higher ethanol blends.
    This low carbon, high octane fuel allows automakers to use advanced 
engine design features that increase engine performance and 
significantly improve fuel efficiency. These engine design features, 
such as higher compression ratios, are limited by current fuels because 
low octane fuels cannot mitigate engine knock. High octane fuel limits 
knock, enabling automakers to design more fuel efficient vehicles, 
leading to lower GHG emissions. Current fuel standards limit the use of 
these advanced engine technologies and leave automakers with fewer 
options to meet higher fuel economy standards.
    Demonstrated through significant research, high octane fuel such as 
98 RON supports fuel efficiency gains of five percent or more, and 
increased fuel efficiency reduces greenhouse gas emissions. By 
requiring that a fuel used to enhance octane also reduces GHG emissions 
compared with unblended gasoline, a LCOS further decarbonizes liquid 
fuels as vehicle technologies advance.
    According to Department of Energy's analysis, because of ethanol's 
high octane rating, a low carbon, high octane mid-level ethanol blend 
would provide significant GHG reduction benefits through both increased 
vehicle efficiency and by offsetting petroleum with lower emissions 
renewable fuel. Priced lower than unblended gasoline, ethanol is the 
most cost-effective octane source, providing the greatest efficiency 
gains at the lowest cost to drivers. A 98 RON E25 blend, for example, 
would provide a further GHG reduction from additional ethanol 
offsetting petroleum on top of the GHG reduction from the fuel 
efficiency gains. We look forward to working on the Next Generation 
Fuels Act in the 117th Congress, demonstrating how agriculture can 
contribute to addressing climate change through the use of more low 
carbon renewable fuels, and carbon sequestration through sustainable 
farming practices.
    NCGA stands ready to assist this Committee as it carves a path 
forward on this important policy issue. Thank you again for the 
opportunity to provide this statement for the record.
            Sincerely,
            
            
John Linder,
President,
National Corn Growers Association.
                                Letter 3
   on behalf of julia olson, executive director, our children's trust
February 23, 2021

    Chair Spanberger and Ranking Member LaMalfa, Full Committee on 
    Agriculture

    Re: Materials for February 25, 2021 Hearing on Climate Change and 
            the U.S. Agriculture and Forestry Sectors

    Dear Chair Spanberger and Ranking Member LaMalfa,

    On behalf of Our Children's Trust (``OCT''), a nonprofit 
organization dedicated to securing the legal right to a stable climate 
system for youth and future generations, please find enclosed herewith 
materials for your consideration relevant to the House Committee on 
Agriculture's February 25, 2021 hearing, ``Climate Change and the U.S. 
Agriculture and Forestry Sectors.'' This submission will inspire you 
with the stories of courageous children and provide resources critical 
to developing science-based, technically and economically feasible 
solutions to the climate crisis.
    Through youth-led constitutional legal actions, including Juliana 
v. United States (``Juliana'')--the landmark Federal constitutional 
climate case filed by twenty-one youth plaintiffs, including eleven 
Black, Brown and Indigenous youth--OCT supports youth seeking to hold 
their governments accountable for policies and actions that have 
caused, and continue to cause, the climate crisis. Through these 
actions, youth seek science-based remedies to reduce greenhouse gas 
emissions at rates necessary to protect their fundamental human rights.
    It is OCT's understanding that the materials submitted for the 
February 25th hearing will inform the Committee's outlook on climate 
impacts and future climate policy and legislation on sustainable 
practices in the agriculture and forestry sectors as it works in tandem 
with President Biden's bold actions to combat the climate crisis. Given 
our mission, OCT has a substantial interest in ensuring that any such 
legislation is consistent with what the best available science dictates 
is necessary to stabilize the climate system and protect the 
fundamental rights of youth and future generations.
    We invite you to consult the materials enclosed herewith, which 
demonstrate that climate change is already harming the fundamental 
rights of young people in the United States and legislation which 
ensures emissions reductions and sequestration of excess CO2 
is necessary for the protection of the fundamental rights of American 
children. Please note in Exhibit D below, the prescription to stabilize 
the atmosphere is a return to atmospheric CO2 levels to 350 
ppm by 2100, limiting global warming to less than 1 Celsius by 2100. 
This requires that net negative CO2 emissions be achieved 
before mid-century.
    Specifically, enclosed as Exhibit A is a summary of the Juliana 
case, including plaintiffs' profiles. Enclosed as Exhibit B you will 
find impact statements of youth from the Federal case supported by OCT, 
Juliana v. United States, which demonstrates some of the profound ways 
that climate change is already affecting the fundamental rights of 
young people, including youth of color and indigenous youth in 
frontline and vulnerable communities. Jacob Lebel and Alex Loznak's 
family farms in Oregon have been impacted by increased heat waves and 
drought conditions, wildfire, and pest infestations. Due to drought, 
water scarcity and failed attempts at dryland farming, Jamie Butler's 
family moved away from their traditional lands and home on the Navajo 
Nation Reservation in Arizona.
    Enclosed as Exhibit C is the expert report of Dr. G. Philip 
Robertson, University Distinguished Professor of Ecosystem Ecology in 
the Department of Plant, Soil and Microbial Sciences at Michigan State 
University and Scientific Director for the Department of Energy's Great 
Lakes Bioenergy Research Center at the University of Wisconsin and 
Michigan State University. This expert report estimates the potential 
for increased carbon sequestration from U.S. forest, range, and 
agricultural land management. Dr. Robertson concludes:

          Over the period 2020 to 2100, changes to land management 
        practices in the U.S. could mitigate . . . over 30% of the 
        negative and avoided emissions needed, after phasedown of 
        fossil fuel emissions, to return Earth's atmosphere to a more 
        stable state.
          Avoiding tillage with no-till technology is one well-
        recognized practice to rebuild soil carbon . . . Adding winter 
        cover crops to avoid bare soil for most of the year can 
        increase soil carbon, as can diversifying crop rotations . . . 
        and applying compost or manure. Growing perennial grasses or 
        trees on degraded or low value agricultural soils can also 
        result in significant carbon gains.
          On pastures and rangeland, soil carbon storage can be 
        improved by increasing plant productivity via improved plant 
        species and by avoiding overgrazing via careful attention to 
        the number of livestock per acre. About 43% of all pasture and 
        rangeland in the U.S. is managed by Federal agencies.
          Forests can also be managed to enhance carbon sequestration 
        in trees and soil. Faster growing species accumulate more 
        carbon over their lifetimes and therefore planting more of 
        these species will store more carbon in wood, as will growing 
        trees in longer rotations (the number of years between 
        harvests) . . . About 42% of all forestland in the conterminous 
        U.S. is managed by Federal agencies.

    Enclosed as Exhibit D you will find a document entitled 
``Government Climate and Energy Actions, Plans, and Policies Must Be 
Based on a Maximum Target of 350 ppm Atmospheric CO2 and 1 
C by 2100 to Protect Young People and Future Generations.'' This 
document details the scientific basis underlying, and prescription for, 
stabilization of the climate system as necessary to protect the 
fundamental human rights of youth and future generations relative to 
the climate crisis and explains that allowing warming of up to 1.5 C 
is not safe.
    Enclosed as Exhibit E include reports published by the energy 
experts at Evolved Energy Research. Exhibit E.1 is an executive summary 
entitled ``350 PPM Pathways for the United States,'' which demonstrates 
multiple technologically and economically feasible pathways for 
transitioning to a 100 percent clean energy economy consistent with the 
science-based prescription for stabilizing the atmosphere and securing 
the fundamental rights of youth and future generations. The report 
demonstrates multiple technically and economically feasible pathways 
for transitioning to a 100 percent clean energy economy consistent with 
the science-based prescription for stabilizing the climate system and 
securing the fundamental rights of youth and future generations. The 
pathways reduce greenhouse gas emissions in the United States at a rate 
consistent with returning global concentrations of CO2 in 
the atmosphere to 350 ppm by 2100, limiting global warming to less than 
1.0 C by 2100. This requires that net negative CO2 
emissions be achieved before mid-century. The report provides important 
policy guidance to achieve this steep and necessary level of emissions 
reductions in the United States. Enclosed as Exhibit E.2 is an 
executive summary entitled ``350 PPM Pathways for Florida'' that 
mirrors the national study's target. Updated national data is included 
in the full report as the U.S. model was upgraded to reflect the newer 
and even lower costs for renewable technologies. The U.S. data from the 
Technical Supplement (page 71) is also included under this Exhibit.
    Legislation which ensures emissions reductions and sequestration of 
excess CO2 consistent with what the best available science 
dictates is necessary for the protection of the fundamental rights of 
young people and future generations. The information in these Exhibits 
are additionally relevant to a forthcoming reintroduction of a House 
concurrent resolution on Children's Fundamental Rights and Climate 
Recovery \1\ supporting the Juliana youth plaintiffs. It recognizes the 
disproportionate effects of the climate crisis on children and their 
fundamental rights which demands renewed U.S. leadership and 
development of a national, science-based climate recovery plan. This 
resolution, sponsored by Representative Schakowsky and originally 
introduced in September 2020, had the support of 61 cosponsors from 
both chambers.
---------------------------------------------------------------------------
    \1\ https://www.congress.gov/bill/116th-congress/house-concurrent-
resolution/119?r=1&s=6.
---------------------------------------------------------------------------
    Should you have any questions regarding the enclosed materials, 
please feel free tocontact Liz Lee, OCT's government affairs staff 
attorney at [Redacted].
            Sincerely,

Julia Olson,
Executive Director,
Our Children's Trust.
Exhibit A: Juliana v. United States Summary and Plaintiffs' Profiles
Juliana v. United States
Young Americans Fight for Their Constitutional Rights and Climate 
        Recovery
Background
    Represented by attorneys at Our Children's Trust,\1\ 21 young 
Americans filed their constitutional climate lawsuit, Juliana v. United 
States, against the Executive Branch of the U.S. Government in 2015. 
They assert that the government's affirmative actions causing climate 
change have violated their constitutional rights to life, liberty, 
property, and equal protection of the laws, and impaired essential 
public trust resources. They seek a court-ordered, science-based 
climate recovery plan, to put the U.S. on track to bring atmospheric 
carbon dioxide levels back to 350 parts per million (ppm) by 2100, 
which would limit long-term warming to less than 1 C, which scientists 
say is the safe target to stabilize the planet's climate system.
---------------------------------------------------------------------------
    \1\ https://www.ourchildrenstrust.org/.
---------------------------------------------------------------------------
    In May 2019, a team of renowned energy experts, Jim Williams, Ben 
Haley, and Ryan Jones, published a report \2\ that demonstrates the 
technical and economic viability of the U.S. to meet this standard by 
2100. An October 2020 report \3\ on specific pathways for Florida to 
meet this standard also provides updated U.S. data.
---------------------------------------------------------------------------
    \2\ https://www.ourchildrenstrust.org/350-ppm-pathways.
    \3\ https://www.ourchildrenstrust.org/350-ppm-pathways-florida.
---------------------------------------------------------------------------
History
    The U.S. District Court has repeatedly found that the youth 
plaintiffs have legitimate claims for trial. In a groundbreaking 
decision in November 2016, the court found that the U.S. Constitution 
secures the fundamental right to a climate system capable of sustaining 
life; that plaintiffs' injuries give them standing to bring their 
claims; and that the Court has authority to remedy the youth's 
injuries.
    Since that historic ruling, the defendants have relentlessly 
attempted to prevent Juliana v. U.S. from going to trial. Three times 
in 2018, the Ninth Circuit Court of Appeals ruled resoundingly against 
government attempts to stop the case. The U.S. Supreme Court has also 
ruled in favor of the youth, twice refusing to halt the case.
    On January 17, 2020, a divided panel of the Ninth Circuit Court of 
Appeals found for the plaintiffs in nearly every respect, but 
ultimately ruled that the courts cannot stop the Executive Branch of 
government from harming children with its policies that cause climate 
change. The plaintiffs filed a petition for rehearing on March 2, 2020, 
supported by ten amicus curiae briefs, including 24 Members of Congress 
and constitutional law experts.
Looking Forward
    On February 10, 2021, while a judge requested a vote, the Ninth 
Circuit denied the plaintiffs' request to rehear their lawsuit without 
explanation. Plaintiffs are now planning to seek review in the U.S. 
Supreme Court. The plaintiffs are also requesting that the Biden-Harris 
Administration and the Department of Justice meet with the plaintiffs 
to discuss settling their claims, and thereby protect their rights and 
the rights of children to come.
Support These Brave Plaintiffs
    The youth plaintiffs deserve to have their constitutional claims 
heard, and need your support now. Please publicly support their right 
to have their constitutional claims upheld in a court of law. Support 
the Congressional resolution recognizing children's fundamental rights 
and the need for a national, science-based climate recovery plan at 
ourchildrenstrust.org/congressionalresolution. The resolution, 
originally introduced on September 23, 2020, was supported by 63 
Members of Congress. Also, join future amicus curiae briefs in support 
of their constitutional rights and the judiciary exercising its Article 
III powers in their case. Show our nation's children you care about 
their future, and the future of all generations to come.
Juliana v. United States: Meet the Plaintiffs
          Meet all 21 Juliana plaintiffs at ourchildrenstrust.org/
        federal-plaintiffs
          Learn more about their stories in this 60 Minutes \4\ segment 
        (bit.ly/60minsjuliana) and their visit to Congress in this 
        video \5\ (bit.ly/yearsprojectjuliana) from The YEARS Project
---------------------------------------------------------------------------
    \4\ https://www.youtube.com/watch?v=C1g2K4DRxLo&feature=emb_title.
    \5\ https://www.youtube.com/watch?feature=youtu.be&v=sd5K1ms1tOc.

    For over 5 years, these young plaintiffs, all of whom have been 
personally impacted by climate change, have been leading the game-
changing litigation campaign to secure the legal right to a stable 
climate for young people, based on the best available science. In 2015, 
they filed their constitutional climate lawsuit against the U.S. 
government in the U.S. District Court for Oregon.


                                  Kelsey Juliana, 24, Eugene, OR

                                  Fighting climate change since she was 
                                10, Kelsey has been increasingly 
                                exposed to hazardous wildfire smoke in 
                                her hometown. As a teenager, she 
                                participated in the Great March for 
                                Climate Action, marching 1,600 miles 
                                from Nebraska to D.C. Time Magazine 
                                recognized Kelsey as a Rising Star in 
                                its list of the Next 100 Most 
                                Influential People in the World.
                                
                                
                                  Vic Barrett, 21, White Plains, NY

                                  A Garifuna American, Vic has spoken 
                                about environmental justice issues and 
                                how his climate anxiety is increased 
                                because his identities--first 
                                generation, trans, indigenous, Latinx, 
                                Black, youth--make him uniquely 
                                vulnerable to the climate crisis. In 
                                2019, he testified at a historic joint 
                                hearing of the House Foreign Affairs 
                                and Select Committee on the Climate 
                                Crisis alongside Greta Thunberg.
                                
                                
                                  Jaime Butler, 20, Flagstaff, AZ

                                  Jaime is of the Tangle People Clan, 
                                born of the Bitterwater Clan. She grew 
                                up in Cameron, Arizona on the Navajo 
                                Nation Reservation, but had to move due 
                                to water scarcity and failed attempts 
                                at dryland farming. Jaime knows 
                                firsthand the cultural and spiritual 
                                impacts of climate change as she and 
                                her tribe struggle to participate in 
                                their traditional ceremonies due to 
                                climate-related impacts.
                                
                                
                                  Levi Draheim, 13, Satellite Beach, FL

                                  Levi has lived most of his life on a 
                                barrier island in Florida, barely above 
                                sea level and literally washing away 
                                due to sea level rise and storms made 
                                worse by climate change. In 2019, Levi 
                                addressed a youth stakeholder's meeting 
                                with Members of the Senate Democrats' 
                                Special Committee on the Climate Crisis 
                                at the United Nations Foundation. His 
                                baby sister is a source of motivation 
                                and inspiration.
                                
                                
                                  Xiuhtezcatl Martinez, 20, Boulder, CO

                                  Xiuhtezcatl is a renowned hip-hop 
                                artist and activist. He is also the 
                                former Youth Director and now Co-Chair 
                                of the executive board for Earth 
                                Guardians. He has experienced extreme 
                                weather events that have been 
                                exacerbated due to climate change, such 
                                as catastrophic flooding. Raised in the 
                                Aztec tradition, Xiuhtezcatl has spoken 
                                at the United Nations several times, 
                                including in English, Spanish, and his 
                                Native language, Nahuatl.
Exhibit B: Impact statements for plaintiffs_Jacob Lebel, Alex Loznak, 
        and Jamie Butler

------------------------------------------------------------------------
 
------------------------------------------------------------------------
Julia A. Olson (OR Bar 062230)       Joseph W. Cotchett
[email protected]                [email protected]
Wild Earth Advocates                 Philip L. Gregory (pro hac vice)
1216 Lincoln Street                  [email protected]
Eugene, OR 97401                     Paul N. McCloskey
Tel: (415) 786-4825                  [email protected]
                                     Cotchett, Pitre & McCarthy, LLP
Daniel M. Galpern (OR Bar 061950)    San Francisco Airport Office Center
[email protected]                840 Malcolm Road
Law Offices of Daniel M. Galpern     Burlingame, CA 94010
1641 Oak Street                      Tel: (650) 697-6000
Eugene, OR 97401                     Fax: (650) 697-0577
Tel: (541) 968-7164
 
Attorneys for Plaintiffs
 
                      United States District Court
                           District Of Oregon
                             Eugene Division
 
Kelsey Cascadia Rose Juliana;        Case No.: 6:15-cv-01517-TC
 Xiuhtezcatl Tonatiuh M., through
 his Guardian Tamara Roske-          Declaration of Jacob Lebel In
 Martinez; et al.,                    Support of Plaintiffs' Opposition
Plaintiffs,                           to Defendants' Motion to Dismiss;
 
v.
 
The United States of America;        Oral Argument: February 17, 2016,
 Barack Obama, in his official        2:00 p.m.
 capacity as President of the
 United States; et al.,
Federal Defendants.
------------------------------------------------------------------------

    I, Jacob Lebel, hereby declare as follows:
    1. I am an eighteen-year-old resident of Roseburg, Oregon and a 
United States citizen. In 2001, I moved with my family from Quebec, 
Canada to Roseburg. We came to the West Coast to find a place of 
natural beauty and mild weather where we would be able to start a farm 
and live a sustainable lifestyle.
    2. I am currently a 3.9 GPA student at Umpqua Community College and 
Vice-President of the College's Environmental Sustainability Club.
    3. My family founded Rose Hill Farms in Roseburg, Oregon. The Farm 
extends over 350 acres, providing milk, eggs, meat, vegetables, fruits, 
nuts, and products such as wool and timber to me, my family, and 
members of the local community. Our animal breeding programs help 
preserve endangered and unique heritage livestock breeds. The Farm is 
currently transitioning towards meeting all of its energy needs through 
solar and hydroelectric power produced onsite.
    4. I intend to continue working and living on the Farm as an adult 
and I currently take an active role in managing and growing the 
business. Thus, the economic future and sustainability of the Farm is 
very closely tied to my own future. The Farm provides me with fresh, 
healthy food and recreational opportunities and I would like to see my 
own children in the future have these same benefits.
    5. My connection to the Oregon wilderness and to Rose Hill Farms is 
deeply personal. As a child, I was homeschooled and spent most of my 
free time playing in the fields and forests around our house. Family 
trips included swimming in the South Umpqua and hiking the forests 
around Crater Lake, Mount Thielsen, and Toketee Falls. As a teenager, I 
wrote poetry and composed songs drawing on the natural beauty that 
surrounded me on the Farm.
    6. My recreational and aesthetic interests are harmed by 
Defendants' actions to continue producing greenhouse gases at a 
dangerous rate. I regularly see bird species on the Farm, such as the 
American Bald Eagle, the Allen's Hummingbird, the Spotted Owl, and the 
Ruffed Grouse. These species are seeing their survival threatened by a 
changing climate and their range may no longer extend to Douglas 
County. Drought conditions and wildfire activity also severely affect 
the plant biodiversity in Oregon, as well as the state's rivers, 
watersheds, and snowpack.
    7. Defendants' enabling of and lack of action against climate 
change have created an unsafe climate for the future of Rose Hill 
Farms. In the summer of 2015, Douglas County experienced two major 
wildfires: the Cable Crossing and Stouts Creek Fires. Combined, these 
fires burnt 28,000 acres. The massive smoke cloud from the Stouts Creek 
Fire was clearly visible from my family's Farm. Smoky and hazy skies 
became a norm for me during the summer of 2015, affecting my enjoyment 
of outside work and hiking on my family's Farm. This was compounded by 
record temperatures and heat waves that stressed the garden crops and 
livestock and increased my workload, while also making it harder and 
more dangerous to work long hours in the heat.
    8. Rose Hill Farms contains seven permanent structures and three 
greenhouses. These structures include the house where I grew up and 
currently live and a cabin hand built out of wood harvested from our 
own forests and milled in our workshop. As a young adolescent, I helped 
lay planking on the walls and roof and varnish the structure. This 
cabin and our entire infrastructure is now at heightened risk from 
increased wildfire activity in Douglas County.
    9. Approximately four-hundred fruit and nut trees grow on our Farm, 
many of them over thirteen years old. I take special pleasure in 
walking through the groves of Asian pear and peach trees and picking 
ripe figs and pomegranates from our plantations. As a small boy, I 
helped plant many of these trees and they are part of the heritage I 
want to pass on to my children. In addition to the spiritual and 
aesthetic meaning these orchards have for me, they represent a 
significant economic asset for my family and me, bringing in roughly 
$20,000 in revenue every year.
    10. In the past 4 years, Rose Hill Farms has experienced an 
infestation of a new invasive insect pest called the Spotted-Wing 
Drosophila (Drosophila Suzukii). The Suzuki fly, which lays its eggs in 
unripe soft fruits, has become a serious problem for the entire 
Northwest fruit and berry industry. A warmer climate promotes the 
spread of the Suzuki fly population and other insect pests by 
increasing their metabolisms and allowing them to overwinter safely. 
Weather extremes, such as droughts in summer and heavy rains in spring 
and winter, also stress the fruit trees and decrease their ability to 
defend themselves from fungal infections and pest attacks. Since the 
Suzuki fly infestation started, I have had to put in extra hours of 
labor each summer in order to cope with the increasing frequency of 
sprays needed to protect the crops.
    11. As a result of the Suzuki fly invasion, the Farm has incurred 
crop losses to our nectarine, peach, and cherry orchards, amounting to 
approximately $20,000. More gravely, due to their foreign qualities, 
there is currently no organically approved pesticide that effectively 
combats these particular pests without relying on a repetitive usage 
leading to resistance. For the first time, we have been forced to spray 
non-organically approved pesticide on our trees in order to save the 
crops. This spraying prevents us from attaining organic certification 
on any farm products for 5 more years after we stop using this 
pesticide and represents an incalculable loss of profit from our 
operation.
    12. Rose Hill Farms contains five ponds that fill from rainfall and 
groundwater during the winter and provide all the water for our 
livestock, gardens, and orchards during the summer. During the summer 
of 2015, for the first time in the 10 years since the ponds were 
excavated, I watched them run dry due to drought conditions. We were 
forced to ration irrigation water during a summer which saw the highest 
June temperatures ever recorded across Oregon.
    13. Water shortages due to drought conditions have forced my family 
to begin implementing an extended water collection and irrigation 
system, which includes three additional ponds and a large scale solar 
pumping and water transport system. Costs for the project are projected 
to reach $15,000.
    14. I also enjoy winter recreation and sports, including 
snowboarding, sledding, and hiking in the snow. Having spent the first 
3\1/2\ years of my life in Canada, recreating in cold weather and deep 
snow with my family helps me reconnect with my roots. I learned to 
snowboard at the Mount Hood ski resort and retain magical memories of 
soaking in the snowy outdoor spa and pool and enjoying the breathtaking 
winter vistas.
    15. Rising global temperatures caused by Defendants as set forth in 
our Complaint are already affecting my ability to enjoy activities that 
require snow. Due to an historic lack of snow last year, the Mt. 
Ashland ski resort remained closed throughout the winter of 2014, Mount 
Hood received record low snowfall, and the Willamette Pass resort was 
only open for a handful of days. That winter, we had been planning a 
skiing/snowboarding trip to the Willamette Pass Resort, which we were 
forced to cancel.
    16. Every year since 2010, my family has rented a cabin in Bandon 
on the Oregon coast for several days to a week. During these annual 
visits, I enjoy walking the shoreline and exploring the caves exposed 
by low tide. I want to be able to bring my own children to marvel at 
the sea stars and crabs in tidal pools. However, due to rising sea 
levels and changing ecology, this stretch of coastline and many of the 
species that inhabit it will not be available for recreation and 
enjoyment by my family and me.
    17. I vividly remember going on my first crabbing trip. The 
excitement of reeling in a pot full of the brilliantly colored 
crustaceans and then being able to cook and eat them fresh off the boat 
was unprecedented for me. This opening of the 2015 Dungeness crab 
season in Oregon was unusually delayed from its usual December 1st date 
and was still closed on Jan 3rd. In California, the crab season 
traditionally starts even earlier (on November 15th); it also has yet 
to open. This has been officially attributed to an unprecedented toxic 
algae bloom triggered by warmer ocean temperatures. Ocean acidification 
is endangering the survival of the crabs and all the shelled seafood 
that I consume.
    18. In addition to crab fishing, which I intend to continue if 
possible, my family and I receive monthly deliveries of fresh seafood 
from Port Orford Sustainable Seafood. These deliveries form an integral 
part of my regular diet and include Dungeness crab and clams. This 
winter we were told there would be no crab available for Christmas.
    19. My family and I also often procure a permit to harvest mussels 
from seashore rocks in Bandon, Oregon. However, algae bloom biotoxins 
are forcing Oregon officials to restrict mussel harvesting for longer 
and longer periods. It is not easy for me to find a time for a seaside 
trip when the mussels are safe to eat. Furthermore, oyster, mussel, and 
clam populations are already shrinking due to ocean acidification and 
lack of oxygen. The effects of ocean acidification and ocean warming 
stemming from Defendants' actions are already affecting my food supply 
and my ability to personally participate in activities such as crab-
fishing and mussel gathering.
    20. The expansion and creation of new fossil fuel infrastructure, 
such as the proposed Jordan Cove Project in Southern Oregon, conducted 
as a result of Defendant's energy policies, also threaten my family's 
Farm and my way of life.
    21. The border of the Farm is located approximately 1 mile from the 
route of the proposed Pacific Connector Pipeline. If built, the 
pipeline and the associated 100-150 wide clear-cut may be visible from 
scenic points on the Farm where I regularly hike. This would cause me 
significant emotional distress and harm my enjoyment of the Farm.
    22. According to testimony by oyster farmers such as Lili Clausen 
of Coos Bay, silt and water conditions that would be created by 
construction of the Pacific Connector Pipeline and Jordan Cove 
liquification factory would harm oyster beds. The oysters that I eat 
are mostly bought locally in Coos Bay and construction of this project 
would harm this important food supply.
    23. If built, Jordan Cove would be the single biggest emitter of 
greenhouse gases in Oregon once the Boardman Coal-Fired Power Plant 
closes in 2020. The pipeline would require a clearcut through old-
growth, carbon sequestering forests. This project would contribute to 
climate change and worsen its impacts on my life.
    24. The danger of explosions along the length of the Pacific 
Connector Pipeline would heighten the risk of a wildfire starting 
nearby to our Farm. Williams Pipeline, the company that would build the 
pipeline, has already had four explosion incidents on its pipelines and 
facilities. Coupled with already severe fire seasons and drought 
conditions, the Pacific Connector Pipeline would put my family's Farm 
in constant danger. These extreme climate conditions created by 
Defendants and the continuation of fossil fuel production projects such 
as Jordan Cove are harming my daily life as well as my future ability 
to enjoy and sustain myself.
    I certify under penalty of perjury in accordance with the laws of 
the State of Oregon, and to the best of my knowledge, that the 
foregoing is true and correct.
    Dated this 5th day of January, 2016 at Roseburg, Oregon.
    
    
                                                       Jacob Lebel.    

------------------------------------------------------------------------
 
------------------------------------------------------------------------
Julia A. Olson (OR Bar 062230)       Joseph W. Cotchett
[email protected]                [email protected]
Wild Earth Advocates                 Philip L. Gregory (pro hac vice)
1216 Lincoln Street                  [email protected]
Eugene, OR 97401                     Paul N. McCloskey
Tel: (415) 786-4825                  [email protected]
                                     Cotchett, Pitre & McCarthy, LLP
Daniel M. Galpern (OR Bar 061950)    San Francisco Airport Office Center
[email protected]                840 Malcolm Road
Law Offices of Daniel M. Galpern     Burlingame, CA 94010
1641 Oak Street                      Tel: (650) 697-6000
Eugene, OR 97401                     Fax: (650) 697-0577
Tel: (541) 968-7164
 
Attorneys for Plaintiffs
 
                      United States District Court
                           District Of Oregon
                             Eugene Division
 
Kelsey Cascadia Rose Juliana;        Case No.: 6:15-cv-01517-TC
 Xiuhtezcatl Tonatiuh M., through
 his Guardian Tamara Roske-          Declaration of Alexander Loznak In
 Martinez; et al.,                    Support of Plaintiffs' Opposition
Plaintiffs,                           to Defendants' Motion to Dismiss;
 
v.
 
The United States of America;        Oral Argument: February 17, 2016,
 Barack Obama, in his official        2:00 p.m.
 capacity as President of the
 United States; et al.,
Federal Defendants.
------------------------------------------------------------------------

    I, Alexander Wallace Loznak, hereby declare as follows:
    1. I am a nineteen-year-old Oregon resident, a United States 
citizen, and a Plaintiff in this action. My family lives on the Martha 
A. Maupin Century Farm in the unincorporated rural area of Kellogg, 
Oregon.
    2. My Educational Background: I graduated as one of the 
valedictorians of the Class of 2015 at Roseburg High School in 
Roseburg, Oregon, and I am currently an undergraduate student at 
Columbia University in New York City. In the summer of 2014, I attended 
The American Legion's Oregon Boys State program. At Boys State, I was 
awarded an academic scholarship from The American Legion and Samsung 
``[f]or excellence in academic pursuits and dedication to the 
community, attributes which are in keeping with the efforts of the U.S. 
service men and women who helped maintain freedom for the citizens of 
South Korea.''
    3. My History of Climate Advocacy: Fighting climate change is one 
of the central objectives of my life. I chose to attend Columbia 
University to have an impact on issues of global significance, 
including the climate crisis. In my application to Columbia, I stated 
``young people--who will inherit either a broken world or a vibrant 
one--must take the lead'' in addressing climate change.
    4. In Oregon, I have advocated for local solutions to the climate 
crisis. I started the Climate Change Club at Roseburg High School, and 
the League of Umpqua Climate Youth (``LUCY''), with the goal of 
installing solar panels at Roseburg High School.
    5. I have lobbied Oregon state legislators to pass House Bill 3470, 
which would create market-based incentives to reduce carbon dioxide 
emissions. Additionally, I have advocated for Federal policies to 
curtail climate change. In the summer of 2013, I wrote a letter to 
President Obama, asking him to take comprehensive action to limit 
fossil fuel extraction and carbon dioxide emissions. A true and correct 
copy of my letter to the President is attached as Exhibit 1.*
---------------------------------------------------------------------------
    * Editor's note: Exhibit 1 was not included in Our Children's Trust 
submission for the record of the hearing.
---------------------------------------------------------------------------
    6. My Opposition to Jordan Cove: I am actively opposed to the 
construction of the Pacific Connector Natural Gas Pipeline and the 
Jordan Cove Energy Project. In November 2013, I wrote an op-ed in the 
Roseburg News-Review to advocate that the Douglas County Planning 
Commission deny a permit for the pipeline. In December 2014, I spoke in 
opposition to the pipeline at a Federal Energy Regulatory Commission 
hearing in Roseburg.
    7. The Effects of Climate Change on My Family's Farm: The Martha A. 
Maupin Century Farm, my permanent residence, contains 570 acres of land 
and sits along the Umpqua River. My great-great-great-great-
grandmother, Martha Poindexter Maupin, founded the farm in 1868 after 
crossing the Oregon Trail. This farm is one of the few Century Farms in 
Oregon named for a woman.
    8. My grandmother, Janet Fisher, is the current owner of the farm. 
In 2014, my grandmother had a book published by Globe Pequot Press 
about Martha's life, A Place of Her Own: The Legacy of Oregon Pioneer 
Martha Poindexter Maupin. The book describes Martha's experience when 
she discovered the Kellogg Crescent area along the Umpqua River, where 
the farm is located: ``She nudged her horse and rode over a gentle rise 
across a saddle of land to a broad overlook. Her breath caught. She 
could see the valley, the river, a plain on the far side, and mountains 
beyond. A breeze stirred, like a whisper saying, `Come.' ''
    9. The farm is my intellectual and spiritual base, and a 
foundational piece of my life and heritage. My family has passed the 
farm from generation to generation, and my identity and well-being 
depend on the preservation and protection of the farm. I want to 
explore the farm with my children someday, and I plan to eventually 
move back to the farm. Unfortunately, drought conditions, unusually hot 
temperatures, and climate-induced migration of forest species are 
harming and will increasingly harm my use and enjoyment of the Martha 
A. Maupin Century Farm.
    10. Agricultural produce from the farm is an important source of 
revenue and food for my family and me. Because I am a student with 
little income, my financial survival depends in large part on the 
continued productivity of the farm. On the farm, my family grows timber 
trees, plum trees, and hazelnut trees. We rent pasture for grass-fed 
beef cattle. We also have a large garden, in which we grow many of the 
fruits and vegetables that we consume. We raise chickens for eggs we 
consume. Climate change, caused in substantial part by the Federal 
Defendants, adversely impacts the productivity of the farm and 
threatens my financial survival.
    11. How Defendants Are Harming My Use of the Farm: Recordsetting 
heat waves, drought, and fire in the region of my farm, caused in 
substantial part by the Federal Defendants, harm my ability to work 
outside on the farm during the summer months. The heat waves and 
drought adversely impact the productivity of the farm, especially my 
family's hazelnut orchard and timber trees.
    12. Exact temperature records are not available for the farm, but 
the temperature at the farm is usually very close to the temperature in 
Roseburg, Oregon. According to the National Weather Service, the 
average temperature in Roseburg for summer 2015 (June through August) 
was 74 Fahrenheit, making it the hottest summer ever recorded there. 
The two previous records were 71.8 and 71.6, set in 2014 and 2013 
respectively.
    13. July 30, 2015 tied the record for the hottest day ever recorded 
in Roseburg, with a high of 108 Fahrenheit. June 27, 2015 set the 
record for the highest-ever low temperature. That means at night, the 
lowest it got was 74. The lowest temperature at night had never been 
so high. At the end of June 2015, temperatures repeatedly exceeded 
100.
    14. Drought came with the heat, and on June 11, 2015, Governor 
Brown declared a drought emergency for Douglas County, where Roseburg 
and the farm are located.
    15. In 2011 and 2012, my family planted a 7 acre hazelnut orchard 
on the farm, in the fertile plain next to the Umpqua River. Hazelnuts 
have historically grown well in Oregon, and according to the Oregon 
Hazelnut Growers Office, our state produces 99% of the U.S. hazelnut 
crop. Planting the orchard on our farm required an investment of about 
$7,400.00 in capital costs. We also planted two new acres of plums, 
which required an investment of just over $1,000.00 in capital costs. 
The planting was also an investment of time and energy, and I dug holes 
in the ground for many of the baby trees. We have plans to plant as 
many as 15-20 additional acres of hazelnut trees in the future. 
Unusually hot temperatures and drought conditions, caused in 
substantial part by the Federal Defendants, adversely impact the health 
of the existing hazelnut orchard and diminish the viability of any 
additional plantings.
    16. Record-setting heat in the summer of 2015 caused our new 
hazelnut trees on the farm to wither. The orchard is not irrigated, so 
my father and I had to provide more water than usual. We watered the 
trees one at a time with a tractor, which required considerable added 
man-hours of labor. Based on information from the late Jeff Olsen, a 
former horticulturist from Oregon State University, we had not expected 
to need to water the hazelnut trees that were planted in 2012 at all in 
2015. We believed that the trees planted in 2012 would be old enough to 
survive the summer without watering. However, even the 2012 crop 
required extra water in the scorching-hot summer of 2015.
    17. Every summer since they were planted, some trees have died, 
requiring my family to buy and plant new ones. Abnormal heat due to 
climate change added to these losses. Future heat waves and drought 
endanger our dream of a large, thriving hazelnut orchard.
    18. Another source of revenue for my family is sustainable harvest 
of Douglas fir trees for lumber. Our farm is Sustainable Forestry 
Initiative-certified, and we take great pride in our role as keepers of 
the land. The total value of merchantable timber owned by my 
grandmother on the farm is approximately $400,000.00, using 
calculations based on a 2007 timber cruise conducted by Barnes and 
Associates, Inc. of Roseburg, Oregon. Additionally, there are roughly 
128 acres of young trees, valued currently at about $120,000.00, which 
will steadily increase in value and become merchantable in the coming 
decades. Wildfires, which are increasing in frequency and intensity 
from the changing climatic conditions caused in substantial part by the 
Federal Defendants, threaten to destroy my family's timber.
    19. Increased drought and heat waves, caused in substantial part by 
the Federal Defendants, make it difficult for new timber trees to grow 
after cutting. For example, last year my father replanted a small 
acreage of Douglas fir trees on the farm. These trees were located on a 
southwest-facing slope, which exposed them to the elements and made 
them especially sensitive to heat. Unusually high temperatures during 
the summer of 2015 killed most of the trees. We now have to replant 
this section again. While this particular planting was done by my 
father at no capital cost, other plantings have typically run about 
$176 per acre for trees and labor.
    20. Increased fire risk and longer fire seasons make it difficult 
to operate machinery on the farm in the summer months. For example, hot 
temperatures limit the times of day when chainsaws can be used.
    21. My family uses firewood to heat our home in the winter, and we 
typically cut firewood in the summer. The Douglas Forest Protective 
Association (``DFPA'') issues rules for the use of machinery outdoors 
during fire season in Douglas County, where the farm is located. Due to 
high summer temperatures, the DFPA frequently issued Fire Precautions 
of Level II and above in 2015, prohibiting the use of chainsaws 
outdoors between the hours of 1:00 p.m. and 8:00 p.m. This forced my 
family to limit woodcutting to the morning and nighttime hours. 
Unusually hot temperatures, caused in substantial part by the Federal 
Defendants, have made it increasingly difficult to find times to cut 
sufficient firewood.
    22. My family has designated certain wooded areas on the farm not 
to be cut, and these areas are of particular aesthetic and spiritual 
significance to me. I discovered these areas as a little boy, and I 
want these areas to remain intact into my old age. One protected area 
is a grove of Douglas Fir trees that are nearly 80 years old. A picture 
hangs in my grandmother's office of her late father, Gene Fisher, 
walking through these trees in his overalls and a baseball cap. Grandpa 
Gene named the area The Cathedral, perhaps because the trees look like 
pillars, or perhaps because of the way the light filters through their 
branches. Protected areas such as The Cathedral are threatened by the 
increased drought, heat waves, and wildfire risk caused in substantial 
part by the Federal Defendants.
    23. The farm is home to many different species of wildlife, 
including bears, mountain lions, reptiles, amphibians, and birds, which 
I enjoy seeing. In particular, I enjoy visiting ponds in the spring and 
summer, when they are teeming with Pacific Tree Frogs and Rough-Skinned 
Newts. My family hunts deer, elk, and wild turkeys to provide food. In 
the summer, I catch bass from the Umpqua River for food. Each of these 
species of wildlife is adversely impacted by climate change caused in 
substantial part by the Federal Defendants. Changing migration patterns 
and availability of food species harms my and my family's sources of 
sustenance and interest in living off of our land's bounty.
    24. I enjoy fishing for steelhead and salmon on the Umpqua River 
where it runs by the farm. Sea level rise, increasing water 
temperature, ocean acidification, and drought, caused in substantial 
part by the Federal Defendants, are harming, and will increasingly 
harm, salmon and steelhead populations. In the summer of 2015, the 
Oregon Department of Fish and Wildlife curtailed salmon fishing on 
rivers including the Umpqua due to stress on salmon from abnormally 
high water temperatures and low stream flows.
    25. I enjoy swimming in the Umpqua River where it runs past the 
farm. Increased summer temperatures contribute to toxic algae blooms, 
which can make it unsafe to swim in the river. In 2009, four dogs were 
killed by toxic blue-green algae in Elk Creek, a tributary of the 
Umpqua River, about 5 miles from my home. The state issued a health 
advisory for Elk Creek and adjacent sections of the Umpqua River, and I 
abstained from swimming in the river for several weeks after the 
incident for fear of toxic algae.
    26. How Defendants Are Harming My Recreational Interests: In 
addition to recreating on the farm, I also enjoy recreating at other 
locations in Oregon, such as the forests surrounding the North Umpqua 
River. One of my favorite places to recreate is the area around Twin 
Lakes, along the North Umpqua River, where two bright-blue lakes are 
surrounded by old-growth forest. I enjoy hiking, swimming, camping, and 
other activities along the North Umpqua River and I have plans to 
continue doing these activities each year in the immediate future. The 
forests surrounding the North Umpqua River are threatened by the 
increased number and severity of wildfires caused in substantial part 
by the Federal Defendants.
    27. In the summer of 2015, two large wildfires--the Cable Crossing 
and Stouts Creek Fires--burned a combined total of over 28,000 acres in 
Douglas County. Massive columns of smoke from both fires were visible 
from Roseburg, and the plume from the Stouts Creek fire was visible 
from my family's farm. Seeing the columns of smoke caused significant 
distress for my family and me.
    28. Both fires burned in areas where I had previously recreated. 
Due to the Cable Crossing Fire, my friends and I were unable to camp 
along the North Umpqua River on the weekend of July 30, 2015, which we 
would have done but for the fires.
    29. In the winter, I enjoy recreating with my friends in the snow 
in the Oregon Cascades. I have many fond memories of sledding, snow 
fights, and hot chocolate at Diamond Lake, including one time in eighth 
grade, when two of my friends tried to bury me in the snow. Decreased 
snowpack as a result of warmer temperatures caused in substantial part 
by the Federal Defendants will adversely impact my enjoyment of the 
forest in winter. My participation in winter sports such as skiing and 
snowshoeing will be particularly affected.
    30. I also enjoy recreating along the Oregon Coast. My family 
occasionally goes crabbing for food, and I enjoy eating fresh seafood 
at restaurants on the coast. Some of my favorite activities include 
beachcombing and tide-pooling. Sea-level rise and ocean acidification, 
caused in substantial part by the Federal Defendants, are increasingly 
harming the delicate coastal ecosystems where I recreate.
    31. When I was eleven years old, my family and I visited a beach at 
Cape Arago State Park, along the Southern Oregon Coast. To my 
wonderment, I found dozens of Purple Shore Crabs, each no more than 1" 
or 2" in length, hiding under the rocks. There are thousands of crabs 
there, all of them along just a small section of shoreline. I have 
returned to that beach several times, and plan to do so again in the 
immediate future. If the Federal Defendants' actions to allow and 
promote unsafe levels of carbon pollution are not stopped, sea level 
rise and ocean acidification will dramatically alter the narrow 
ecological band in which the crabs exist.
    32. Another location on the coast where I enjoy recreating with my 
family is Sea Lion Caves, near Florence, Oregon. Sea Lion Caves is the 
largest sea cave in the United States, and it is inhabited by dozens of 
elegant Stellar Sea Lions. The sea lions are visible as they rest on 
rocks inside the cave. Multi-meter sea level rise could permanently 
submerge many of the rocks, making the cave inhospitable to the sea 
lions. The ocean ecosystem that supports the sea lions will also be 
increasingly damaged by ocean acidification and abnormally high sea 
surface temperatures due to climate change. I plan to return to Sea 
Lion Caves with my own children someday and hope that a healthy 
population of sea lions continues to live there.
    33. I enjoy hiking in Northern Washington and Glacier National 
Park, where I have seen glaciers receding due to climate change. I plan 
to return to Montana and Washington in the next several years, and I 
also want to travel to Alaska. My recreational and aesthetic interests 
are harmed as the glaciers continue to disappear before I can visit 
them.
    34. In the summer of 2012, I hiked to the top of Desolation Peak in 
North Cascades National Park in Washington. At the top of the mountain 
is a fire-spotting cabin where author Jack Kerouac served as a lookout 
in 1956 and drew the inspiration for his books The Dharma Bums and 
Desolation Angels. In The Dharma Bums, Kerouac describes the land 
surrounding Desolation Peak as ``hundreds of miles of pure snow-covered 
rocks and virgin lakes and high timber.'' I met a fire-spotter from the 
National Park Service there. He told me that, if you look at a picture 
from one hundred years ago, the glaciers on the surrounding mountains 
are twice the size they are today. In that moment, I knew that climate 
change would become a central theme of my life.
    35. My Health Has Been Affected: Recent summers at home have become 
increasingly smoky due to the increased severity and number of 
wildfires in southern Oregon. I have asthma, which is aggravated by the 
smoke. Increased pollen due to unusually warm temperatures also 
aggravates my asthma and allergies. When I am suffering from asthma and 
allergies, my outdoor activities are limited, which harms both my 
ability to work on the farm and my ability to recreate and enjoy the 
special forests and rivers surrounding my home. My asthma and allergies 
will continue to worsen as climate change worsens and air quality 
during the summer months continues to decline.
    36. How I Am Affected By the Export Authorizations for the Jordan 
Cove Project: My family's farm is only about 30 miles from the route of 
the proposed Pacific Connector Natural Gas Pipeline, which would 
connect to the Jordan Cove Liquefied Natural Gas Terminal at Coos Bay. 
The Jordan Cove Terminal would be the largest single source of 
greenhouse gas emissions in the State of Oregon after the scheduled 
closure of the Boardman Coal-Fired Power Plant in 2020.
    37. The potential climate impact of the Jordan Cove Energy Project 
becomes much larger when one also considers upstream emissions from the 
extraction and transport of the natural gas, as well as downstream 
emissions from the combustion of the fuel. Natural gas is made up 
primarily of methane, which is a potent greenhouse gas. This means that 
significant emissions would result from methane leakage during 
extraction and transport of natural gas for the Jordan Cove Project. 
Additionally, according to the Pacific Connector website, the pipeline 
would carry up to 1 billion cubic feet of natural gas per day. The 
CO2 released from burning that much natural gas would be 
equivalent to the emissions from over four million typical passenger 
cars. Clearly, the construction of the Jordan Cove Energy Project would 
contravene Governor Brown's stated goal to reduce Oregon's greenhouse 
gas emissions.
    38. The pipeline would cross 400 bodies of water in Oregon, 
including two locations along the South Umpqua River where I have 
visited and recreated and intend to return in the immediate future. I 
have visited sections of the route in Southern Douglas County and the 
intersection of the route with the famous Pacific Crest Trail. A 
roughly 100-150 wide clearcut would be required for the pipeline, 
causing substantial damage to these wild places that I enjoy for 
recreation and aesthetic value. I would particularly love to hike the 
Pacific Crest Trail again in the near future, and I hope not to see it 
scarred by the pipeline project. A true and correct picture of me at 
the intersection of the Pacific Crest Trail and the proposed pipeline 
route is included as Exhibit 2.**
---------------------------------------------------------------------------
    ** Editor's note: Exhibit 2 was not included in Our Children's 
Trust submission for the record of the hearing.
---------------------------------------------------------------------------
    39. While walking along the pipeline route, I was shocked to 
discover that workers on public land had already spray-painted numbers 
and markers on old-growth trees to be cut, even though the pipeline has 
not yet received all necessary local, state, and Federal permits. I was 
particularly horrified that workers had spray-painted trees adjacent to 
the Pacific Crest Trail. In my view, this defacement of trees 
demonstrates the pipeline company's confidence-based on its existing 
authorization from the Department of Energy to export the LNG--that it 
will receive the rest of its permits, despite the project's severe 
impacts on the climate and local environment.
    40. One specific location on the pipeline route that I visited was 
near Callahan Ridge, on Bureau of Land Management property in southern 
Douglas County (Township 31s, Range 3w, the NW quarter of section 25). 
A few weeks after I visited the location, the Stouts Creek Fire burned 
this area of the forest. The Stouts Creek Fire directly impacted at 
least a dozen miles of the pipeline route, with the proposed location 
for an aboveground valve inside the fire perimeter. If constructed, the 
pipeline would carry highly pressurized, explosive natural gas through 
Oregon's fire-prone forests, with 17 valves located above ground. This 
would further harm my interests in protecting the places where I 
recreate from the increasing ravages of climate change caused in 
substantial part by the Federal Defendants.
    41. In an April 6, 2015 letter to the Federal Energy Regulatory 
Commission (``FERC''), the U.S. Army Corps of Engineers asked that FERC 
assess ``the impacts of large trees, stumps or slash catching on fire 
during a forest fire event and landing over the buried pipeline and how 
that could affect the ground temperature and buried pipeline integrity/
safety.'' Additionally, in a September 9, 2015 letter to FERC, Douglas 
County Commissioner Chris Boice asked that FERC evaluate ``[h]ow . . . 
a wild land fire [would] impact the integrity of pipeline construction 
and infrastructure both before and after a wild land fire.''
    42. Williams Pipeline, the company that would construct Pacific 
Connector, has had four explosions at other pipelines and facilities in 
the past. Leaking pipelines around the country, like the now-infamous 
Sempra pipeline in Porter Ranch, California, demonstrate how common and 
likely pipeline accidents are, and the risks they will pose in my 
community in southern Oregon. The increased possibility of wildfires in 
places I have visited, such as the area around Callahan Ridge, would 
compound the risk of catastrophic accidents.
    43. The Federal Defendants' disregard for the impacts of wildfires 
on the pipeline mirrors the Federal Defendants' broader disregard for 
the impacts of fossil fuel extraction and combustion on our climate 
system. Changes to the climate system increasingly harm my way of life, 
and direct environmental impacts from the construction of the Jordan 
Cove Energy Project threaten to do so as well.
    I certify under penalty of perjury in accordance with the laws of 
the State of Oregon, and to the best of my knowledge, that the 
foregoing is true and correct.
    Dated this 5th day of January, 2016 at Kellogg, Oregon.
    
    
                                          Alexander Wallace Loznak.    

------------------------------------------------------------------------
 
------------------------------------------------------------------------
Julia A. Olson (OR Bar 062230)       Joseph W. Cotchett
[email protected]                [email protected]
Wild Earth Advocates                 Philip L. Gregory (pro hac vice)
1216 Lincoln Street                  [email protected]
Eugene, OR 97401                     Paul N. McCloskey
Tel: (415) 786-4825                  [email protected]
                                     Cotchett, Pitre & McCarthy, LLP
Daniel M. Galpern (OR Bar 061950)    San Francisco Airport Office Center
[email protected]                840 Malcolm Road
Law Offices of Daniel M. Galpern     Burlingame, CA 94010
1641 Oak Street                      Tel: (650) 697-6000
Eugene, OR 97401                     Fax: (650) 697-0577
Tel: (541) 968-7164
 
Attorneys for Plaintiffs
 
                      United States District Court
                           District Of Oregon
                             Eugene Division
 
Kelsey Cascadia Rose Juliana;        Case No.: 6:15-cv-01517-TC
 Xiuhtezcatl Tonatiuh M., through
 his Guardian Tamara Roske-          Declaration of Jaime B. In Support
 Martinez; et al.,                    of Plaintiffs' Opposition to
Plaintiffs,                           Defendants' Motion to Dismiss;
 
v.
 
The United States of America;        Oral Argument: February 17, 2016,
 Barack Obama, in his official        2:00 p.m.
 capacity as President of the
 United States; et al.,
Federal Defendants.
------------------------------------------------------------------------

    I, Jaime Lynn Butler, hereby declare as follows:

  1.  I am a 15-year-old citizen of the United States and resident of 
            Window Rock, Arizona. I am a freshman in high school at 
            Colorado Rocky Mountain School in Carbondale, Colorado. My 
            family and I are already experiencing harm caused by 
            climate change and I am worried we'll experience even more 
            severe climate impacts in the immediate future.

  2.  I am a member of the Navajo Nation. My clan is Tangle People 
            Clan, born for the Bitter Water Clan, with my maternal 
            grandfathers of the Red House Clan and my paternal 
            grandfathers of the Towering House Clan. I am a member of 
            the Grand Canyon Sierra Club, which is where I first 
            learned about climate change. In 2011, frustrated by my 
            state's lack of action to combat climate change, I filed a 
            lawsuit against the governor of Arizona for violating her 
            duty to protect the atmosphere as a resource under the 
            public trust doctrine.

  3.  I grew up in Cameron, Arizona, on the Navajo Nation Reservation. 
            In 2011, my mom and I had to move from Cameron to Flagstaff 
            because of drought and water scarcity. My extended family 
            on the Reservation remember times when there was enough 
            water on the Reservation for agriculture and farm animals, 
            but now the springs they once depended on year-round are 
            drying up. My mom and I were not able to live sustainably 
            on the Reservation because of the costs of hauling water 
            into Cameron for us and our animals. I am worried that my 
            extended family, all of whom live on the Reservation, will 
            also be displaced from their land, which would erode my 
            culture and way of life. Participating in sacred Navajo 
            ceremonies on the Reservation is an important part of my 
            life, and climate impacts caused by the acts of Defendants 
            are starting to harm my ability, as well as the ability of 
            my family and tribe, to participate in traditional 
            ceremonies. Ceremonies are governed by phases of the moon 
            and seasons. The dry climate and extreme winds have spread 
            the invasive plant species (Camel Thorn) and they have 
            replaced grasslands, river banks are in accessible due to 
            Tamarack, water wells need to be replaced with deeper wells 
            etc. All of this affects our ability to offer livestock, 
            food and water for ceremonies. Ceremonies often require 
            objects secured in nature that were once plentiful IE. 
            medicinal plants, hides, and feathers etc. Now they are 
            not, scarcity means they cost more or are no longer 
            available.

  4.  Once we moved off the reservation, we moved to the outskirts of 
            Flagstaff, along the Kaibab National Forest. The forest 
            there, was my favorite place to spend time. I find peace 
            being outside in the forest surrounding my home, and when I 
            was home I spent hours each day walking in the forest.

  5.  Large parts of the Kaibab National Forest have been destroyed due 
            to pine beetle infestations and forest fires, both of which 
            are caused by, or exacerbated by, fossil fuel emissions 
            authorized by the Federal Defendants. The emissions cause 
            warmer temperatures, which lower the resistance of the 
            trees to the infestations. The hotter temperatures, 
            drought, and pest infestations dry the forest, making it 
            more susceptible to wildfires. I have seen the beetles and 
            they are huge and ugly.

  6.  In 2014, my mom and I were evacuated from our home for 2 days 
            because of the Oak Creek Canyon fire north of our home. 
            Winds brought smoke and ash into our neighborhood. I'm 
            worried that the area surrounding my home is becoming 
            unsafe due to an increase in drought conditions and forest 
            fires caused by the acts of Defendants in permitting, 
            subsidizing, and otherwise allowing unrestrained fossil 
            fuel emissions.

  7.  As a result of the pine beetle infestations and forest fires 
            caused by the acts of Defendants, my ability to spend time 
            in the Kaibab National Forest has been limited and will be 
            limited in the immediate future.

  8.  I have been negatively affected by the increasing temperatures, 
            which limits the time I'm able to safely spend time 
            outdoors. Hotter temperatures and drought also negatively 
            impact the vegetables we grow for food on our property in 
            Flagstaff. Our water bills go up to irrigate our little 
            garden, but the worst problem is how quickly the garden 
            dries up if we are away for an extended time. Also the 
            forest animals (raccoons, coyotes and rabbits) come into 
            our yard, over the fencing to access our water or garden. 
            On the reservation we simply stopped farming. Although we 
            had dryland farmed using drought resistant corn, relying on 
            winter snow, the dry topsoil was too deep to find damp 
            earth over 12 inches in most places. Nothing would grow, so 
            we stopped our efforts. Fewer and fewer people farm, 
            especially dryland farming.

  9.  My severe allergies have become increasingly worse over the last 
            several years. I take over-the-counter medication to combat 
            my symptoms. In the forest it is spring and summer pollens, 
            in the desert on the reservation, it is the dust and 
            sandstorms that make life very hard. I find my family gets 
            sore throats during windy times, especially summer, as the 
            dust affects our breathing.

  10. With record-setting temperatures and a drought that has lasted 
            several years, I fear for my future and for the future of 
            my family, our history, our traditions, and our way of 
            life.

    I certify under penalty of perjury in accordance with the laws of 
the State of Arizona, and to the best of my knowledge, that the 
foregoing is true and correct.
    Dated this 5 day of January, 2016 at Flagstaff, Arizona.
    
    
                                   Jaime Lynn Butler.                  
Exhibit C: Expert Report of Dr. G. Philip Robertson

------------------------------------------------------------------------
 
------------------------------------------------------------------------
                            Expert Report of
 
                           G. Philip Robertson
         University Distinguished Professor of Ecosystem Ecology
                        Michigan State University
------------------------------------------------------------------------
   Kelsey Cascadia Rose Juliana; Xiuhtezcatl Tonatiuh M., through his
                 Guardian Tamara Roske-Martinez; et al.,
 
                               Plaintiffs,
 
                                   v.
 
 The United States of America; Donald Trump, in his official capacity as
                 President of the United States; et al.,
 
                               Defendants.
 
                   In the United States District Court
                           District Of Oregon
                      (Case No.: 6:15-cv-01517-TC)
 
          Prepared for Plaintiffs and Attorneys for Plaintiffs:
------------------------------------------------------------------------
Julia A. Olson                       Philip L. Gregory
[email protected]                [email protected]
Wild Earth Advocates                 Gregory Law Group
1216 Lincoln Street                  1250 Godetia Drive
Eugene, OR 97401                     Redwood City, CA 94062
Tel: (415) 786-4825                  Tel: (650) 278-2957
------------------------------------------------------------------------

Table of Contents
Table of Acronyms, Abbreviations, and Definitions
Introduction
Executive Summary
Expert Opinion

    1.0  Introduction
    2.0  Scale of the Problem
    3.0  Soil Carbon Cycling and Storage

          3.1  Measuring Soil Carbon Storage
          3.2  Soil Carbon Gain by Improved Land Management

                  3.2.1  Cropland Management
                  3.2.2  Cropland Conversion to Perennial Grasses
                  3.2.3  Grazing Lands Management
                  3.2.4  Frontier Technologies
                  3.2.5  Wetlands Restoration
                  3.2.6  Forest Management

          4.0  Agricultural Greenhouse Gas Abatement by Land Management

                  4.1  Measuring Nitrous Oxide and Methane Fluxes
                  4.2  Avoided Emissions by Improved Land Management

                          4.2.1  Reduced Nitrous Oxide Emissions from 
                        Field Crops
                          4.2.2  Rice Water Management for Methane
                          4.2.3  Cellulosic Bioenergy Production on 
                        Grain Ethanol Lands
                          4.2.4  Cellulosic Bioenergy Production on 
                        Marginal Lands

    5.0  Total Mitigation Potentials

          5.1  Global Estimates of Potentials for Soil Carbon Gain
          5.2  U.S. Potentials for Negative and Avoided Emissions by 
        Land Management Change
          5.3  Barriers that Prevent Optimized Biotic Greenhouse Gas 
        Mitigation in the U.S.

    6.0  Concluding Opinions

            Table Of Acronyms, Abbreviations, and Definitions
 
 
 
     BECCS:   bioenergy with carbon capture and storage
         C:   carbon
       Ceq:   carbon equivalent; used to quantitatively compare
               greenhouse gases via a common metric based on global
               warming potentials for individual gases
       CO2:   carbon dioxide; contains 27.3% carbon
     CO2eq:   carbon dioxide equivalent
       EPA:   U.S. Environmental Protection Agency
       DOE:   U.S. Department of Energy
       GtC:   gigatonne of carbon, equivalent to 1 billion tonnes of
               carbon, or 1 PgC; 1 GtC = 1,000 MtC
        ha:   hectare, equivalent to 2.47 acres
      IPCC:   United Nations Intergovernmental Panel on Climate Change
       Mha:   million hectares, 1 Mha is equivalent to 2.47 million
               acres
       MtC:   million tonnes of carbon, sometimes abbreviated MMTC;
               1,000 MtC = 1 GtC
       N2O:   nitrous oxide
      NRCS:   Natural Resources Conservation Service
       PgC:   petagram of carbon, equivalent to 1015 gC
       ppm:   parts per million
        tC:   tonne of carbon, equivalent to 1,000 kgC or 106 gC
      USDA:   U.S. Department of Agriculture
 

    Avoided Emissions: Greenhouse gas emissions not yet released that 
could be avoided if practices were altered from conventional practices. 
This includes fossil fuel emissions that are avoided by substituting 
biofuel combustion for fossil fuel combustion.
    Carbon Sequestration: Any process that removes carbon dioxide from 
the atmosphere and stores the carbon portion in natural sinks like 
soils.
    Negative Emissions: Greenhouse gas (CO2eq) removed from 
the atmosphere with the carbon portion sequestered for long periods of 
time--sometimes indefinitely--within natural carbon sinks like soils 
and forests. In this report, negative emissions are those above and 
beyond the existing rate of natural sinks.
    Federal Land: All U.S. federally-owned or federally-managed lands 
including forest lands, range lands, other agricultural lands, 
wetlands, and waterways.
    Lands of the United States: All lands, both publicly owned and 
privately owned, within the boundaries of the United States.
    Conterminous lands of the United States: All lands, both publicly 
and privately owned, within the 48 adjoining states plus the District 
of Columbia; also known as the contiguous U.S.
    U.S. Forests: All forestlands within the United States Federal 
Forestland: All U.S. federally-owned or federally-managed forestlands.
Introduction
    I, G. Philip Robertson, have been retained by the Plaintiffs in the 
above-captioned matter to provide expert testimony about the potential 
capacity for improved management of United States forest, range and 
agricultural lands to achieve net negative carbon emissions and avoid 
future greenhouse gas emissions. In this report I provide background on 
the global carbon cycle, describe how different land management 
practices can contribute to negative and avoided emissions, and provide 
a quantitative assessment of the potential for changes in management 
practices to provide meaningful greenhouse gas mitigation.
    I have worked in the field of carbon and nitrogen biogeochemistry 
for 40 years since beginning my Ph.D. studies in 1976. I am currently 
University Distinguished Professor of Ecosystem Ecology in the 
Department of Plant, Soil and Microbial Sciences at Michigan State 
University, where I have held a regular faculty position since 1987. I 
have been a University Distinguished Professor for the last 7 years. 
Since 2017 I have also held the title of Scientific Director for the 
Department of Energy's Great Lakes Bioenergy Research Center at the 
University of Wisconsin and Michigan State University. For my entire 
career the main focus of my research has been studying the processes 
that regulate biogeochemical cycles of carbon and nitrogen at multiple 
scales, including plant, soil, and microbial interactions that affect 
the delivery of important ecosystem services such as climate stability, 
water quality, and plant productivity. I work primarily in agricultural 
ecosystems, and more broadly on the issue of agricultural 
sustainability, which includes the responses of cropping systems to 
climate change and the potential for land management to contribute to 
greenhouse gas mitigation. My CV, which includes a statement of my 
qualifications, is contained in Exhibit A * to this expert report. A 
list of publications I authored within the last 10 years is attached as 
Exhibit B * to this expert report.
---------------------------------------------------------------------------
    * Editor's note: the Our Children's Trust submission for the record 
for this hearing does not include Exhibits A-C. It has been reproduced, 
as submitted, herein. The full report is retained in Committee file and 
is available at: http://blogs2.law.columbia.edu/climate-change-
litigation/wp-content/uploads/sites/16/case-documents/2018/
20180628_docket-615-cv-1517_exhibit-11.pdf.
---------------------------------------------------------------------------
    In preparing my expert report and testifying at trial, I am not 
receiving any compensation and am providing my expertise pro bono to 
the Plaintiffs given the financial circumstances of these young 
Plaintiffs. I have not provided previous testimony within the preceding 
4 years as an expert at trial or by deposition. My report contains 
citations to all documents that I have used or considered in forming my 
opinions, listed in Exhibit C * to this report.
    The opinions expressed in this report are my own, not necessarily 
the opinions of any of the institutions for which I work or donate my 
time. The opinions expressed herein are based on the data and facts 
available to me at the time of writing, as well as based upon my own 
professional experience and expertise. All opinions expressed herein 
are to a reasonable degree of scientific certainty, unless otherwise 
specifically stated. Should additional relevant or pertinent 
information become available, I reserve the right to supplement the 
discussion and findings in this expert report in this action.
Executive Summary
    Earth's carbon is found in six reservoirs: rocks, oceans, 
atmosphere, plants, soil, and fossil deposits. In the carbon cycle, 
carbon moves from one reservoir to another. The human-induced transfer 
of carbon from fossil deposits to the atmosphere is causing Earth to 
warm. Even when that transfer ceases, in order to return the 
atmospheric reservoir to a point conducive to human well-being, we will 
need to remove carbon from the atmosphere and store it in other 
reservoirs. This is known as carbon sequestration or negative 
emissions. The potential for increased carbon sequestration from U.S. 
forest, range, and agricultural land management is, at peak, around 
0.414 GtCeq per year (414 MtCeq per year). This 
could result in negative emissions within the U.S. totaling about 21 
GtCeq by 2100. Changes to land management practices could 
avoid the emissions of another 0.12 GtCeq per year, totaling 
9.7 GtCeq by 2100. All told, over the period 2020 to 2100, 
changes to land management practices in the U.S. could mitigate more 
than 30 GtCeq between 2020 and 2100, which is over 30% of 
the negative and avoided emissions needed, after phasedown of fossil 
fuel emissions, to return Earth's atmosphere to a more stable state.
    Three types of CO2 removal are most widely discussed 
today: (1) Improved land management, (2) Bioenergy with CO2 
capture and storage (referred to as BECCS), and (3) Direct air capture. 
BECCS and direct air capture are both theoretically possible but 
currently unproven at any meaningful scale, and thus are not analyzed 
in this report. Of these three, improved land management represents the 
most mature, technically feasible, widely deployable, and lowest cost 
option currently available. Thus, this report focuses on improving land 
management to remove and store CO2 and to reduce future 
emissions of three key greenhouse gases--CO2, nitrous oxide, 
and methane.
    Soil represents one of the largest actively cycling reservoirs of 
carbon on earth, most of which is stored in the form of soil organic 
matter, largely comprised of decomposing plant residue. Almost 
everywhere, conversion of native forest and grasslands to agriculture 
has resulted in a 30-50% loss of this carbon to the atmosphere as 
further decomposition to CO2 is accelerated. Almost all 
soils actively managed for agriculture, as well those that have been 
abandoned from agriculture due to degraded fertility, have soil carbon 
levels well below their original levels, providing significant 
opportunities to sequester additional carbon.
    There are a number of well-tested methods to increase soil carbon 
through agricultural practices on land used to grow annual crops. 
Avoiding tillage with no-till technology is one well-recognized 
practice to rebuild soil carbon. Other practices can be just as 
effective: adding winter cover crops to avoid bare soil for most of the 
year can increase soil carbon, as can diversifying crop rotations--
growing more than one or two crops in sequence--and applying compost or 
manure. Growing perennial grasses or trees on degraded or low value 
agricultural soils can also result in significant carbon gains. On 
pastures and rangeland, soil carbon storage can be improved by 
increasing plant productivity via improved plant species and by 
avoiding over grazing via careful attention to the number of livestock 
per acre. About 43% of all pasture and rangeland in the U.S. is managed 
by Federal agencies.
    Forests can also be managed to enhance carbon sequestration in 
trees and soil. Faster growing species accumulate more carbon over 
their lifetimes and therefore planting more of these species will store 
more carbon in wood, as will growing trees in longer rotations (the 
number of years between harvests). A number of management factors can 
increase forest soil carbon. About 42% of all forestland in the 
conterminous U.S. is managed by Federal agencies.
    In addition to increasing carbon sequestration, changes in land 
management practices on Federal and private lands can also reduce the 
amount of greenhouse gas emissions stemming from land use. Nitrous 
oxide is a greenhouse gas 250-300 times more potent than 
CO2. Agriculture is responsible for 84% of global 
anthropogenic nitrous oxide emissions, and most agricultural emissions 
(62%) come from soils amended with nitrogen from fertilizers, manures, 
or legumes. Reducing nitrogen fertilizer rates to those needed for 
optimum yields is the most reliable means to reduce nitrous oxide 
emissions from fertilized cropping systems.
    Methane is 28-36 times more potent than CO2. 
Agricultural methane emissions come from digestive fermentation by 
livestock (52%), rice cultivation (22%), biomass burning (19%), and 
livestock manure handling (8%). Rice cultivation practices and 
livestock management offer important land-use related methane 
mitigation opportunities. Methane from rice production can be minimized 
through periodic drainage of flooded rice fields.
    Finally, there is an opportunity to reduce greenhouse gas emissions 
and increase carbon sequestration by growing cellulosic bioenergy crops 
such as switchgrass on marginal lands that were formerly in agriculture 
and on lands now used to grow corn for grain ethanol.
    All told, technology is available today to store carbon or avoid 
future greenhouse gas emissions from agriculture in the U.S. equivalent 
to more than 30 GtCeq by 2100. Farmers, ranchers, and 
landowners have shown a willingness to accept payments for implementing 
such practices. Financial incentives and Federal policies will need to 
be aligned with the sequestration practices described below in order to 
achieve this scale of increased sequestration.
Expert Opinion
1.0  Introduction
    Carbon is one of the most abundant elements on Earth. Most of the 
carbon on Earth is stored in rocks. The rest of Earth's carbon is in 
our oceans, atmosphere, plants, soil, and fossil fuels. Earth's carbon 
cycle involves the flow of carbon between each of these carbon 
reservoirs (or sinks). Some of the flow is very slow and some is fast. 
When carbon moves out of one reservoir it enters another, as depicted 
in Figure 1.
Figure 1


          This diagram of the fast carbon cycle shows the movement of 
        carbon between land, atmosphere, and oceans. Yellow numbers are 
        natural fluxes, and red are human contributions in gigatonnes 
        of carbon (GtC) per year. White numbers indicate stored carbon 
        (carbon locked in deep geological reservoirs is not included 
        except for fossil fuel reserves that could be mined). The human 
        contribution, though seemingly small, adds up to a large 
        imbalance and consequent increase in atmospheric 
        CO2. (https://earthobservatory.nasa.gov/Features/
        CarbonCycle/)

    The atmosphere's CO2 content is largely determined by 
the balance between processes that remove CO2 from the 
atmosphere, such as photosynthesis and CO2 absorption by 
seawater, and processes that return CO2 to the atmosphere, 
such as respiration and fossil fuel burning. About 50% of the 
CO2 that humans add to the atmosphere each year by burning 
fossil fuels is removed annually by natural removal and storage 
processes; the remainder accumulates in the atmosphere.
    CO2 transferred from the fossil deposits reservoir to 
the atmosphere through the burning of fossil fuels results in rising 
temperatures on Earth, as predicted by theory in the 19th century. In 
order to restore the Earth's energy balance so that temperatures can 
stabilize at safe levels for humanity and our natural systems, the 
carbon content of the atmosphere must be reduced. Such reductions will 
happen naturally over millennia if carbon emissions from the fossil 
reservoir cease. However, to avoid unsafe temperature increases, 
CO2 must be removed more quickly. Managing plant and soil 
reservoirs for greater carbon storage represents a way to reduce--or 
mitigate--atmospheric CO2. Increasing the amount of carbon 
stored in these reservoirs is commonly referred to as carbon 
sequestration, carbon storage and removal, or negative emissions.
    Decreasing the amount of carbon stored in the atmosphere is widely 
acknowledged to require removing and storing CO2 in other 
carbon reservoirs (negative emissions) as well as curtailing 
CO2 sources such as fossil fuel burning (decarbonization) 
and deforestation. Of almost 900 mitigation scenarios evaluated by the 
Intergovernmental Panel on Climate Change (IPCC) with integrated 
assessment models,\1\ all of the 116 deemed effective involved 
curtailing sources of CO2 and more than 100 also involved 
CO2 removal.2, 3 Both CO2 source 
reduction and CO2 removal are thus central to future climate 
mitigation efforts. Indeed, under any climate recovery scenario, 
negative CO2 emissions (removal and storage) will be 
required starting immediately to bring atmospheric CO2 
concentrations back within safe limits for our biological and human 
systems.4, 5
    Three types of CO2 removal are most widely discussed 
today: (1) Improved land management, (2) Bioenergy with CO2 
capture and storage (referred to as BECCS), and (3) Direct air 
capture.3, 6, 7 Improved land management entails managing 
ecosystems to sequester more carbon in living biomass such as long-
lived trees and in dead biomass such as organic matter in soils and 
ocean sediments. Bioenergy with CO2 capture and storage 
refers to extracting energy by burning biomass and storing the 
resulting CO2 in geologic reservoirs. Direct carbon capture 
involves extracting CO2 directly from the air via enhanced 
weathering of rocks and minerals or direct air capture, with subsequent 
geologic storage. BECCS and direct air capture are both theoretically 
possible but currently unproven at any meaningful scale, and thus are 
not further analyzed in this report. Enhanced rock weathering and ocean 
fertilization have also been proposed but are less widely discussed or 
tested.7, 8 Of this group, improved land management 
represents the most mature, technically feasible, widely deployable, 
and lowest cost option currently available.3, 7 We have 
known about this option and its environmental co-benefits for decades.
    In addition to managing land for negative emissions, land 
management can also contribute to climate mitigation by avoiding 
further greenhouse gas emissions.4, 9 This can be done, for 
example, by reducing deforestation, a practice responsible for 10% of 
total global carbon emissions today,\10\ almost all outside the U.S. 
But greenhouse gases are also emitted by other land management and 
agricultural practices. For example, nitrogen fertilizer emits 
CO2 when manufactured and emits nitrous oxide when applied 
to soils. Methane is emitted by soils under rice cultivation. Land 
management practices that avoid or reduce greenhouse gas emissions thus 
represent an additional climate mitigation opportunity. Some management 
changes have the potential to both curtail CO2 emissions and 
remove CO2 from the atmosphere. For example, producing 
ethanol from perennial grasses instead of corn grain both consumes less 
fossil fuel (curtailing CO2 emissions) and stores more soil 
carbon (enhancing CO2 removal and storage).
    In the pages that follow are current opportunities for improved 
land management practices in the U.S. that are feasible and currently 
available to mitigate climate change. I emphasize those land management 
practices most likely to produce significant negative emissions--those 
that remove and store CO2 from the atmosphere--and as well 
those practices capable of reducing emissions of CO2 and the 
other biogenic greenhouse gases nitrous oxide and methane, respectively 
responsible for 82%, 10% and 5% of total U.S. greenhouse gas 
emissions.\11\
2.0  Scale of the Problem
    From pre-industrial times fossil fuels have added 327 GtC to the 
atmosphere (half of that just since the 1980s),\12\ with another 156 
GtC added by deforestation. In 2014 fossil fuel burning added 8.8 GtC 
to the atmosphere,\13\ with the U.S. responsible for 1.5 GtC \11\ or 
about 17% of the global total that year. In recent years global 
deforestation has added annually another 0.9 GtC,\10\ none from the 
U.S.\11\
    To avoid or deflect the most disruptive effects of climate change 
now underway--sea level rise, shifting climate zones, species 
extinctions, coral reef decline, climate extremes, expanded forest 
burning, and human health impacts--requires returning atmospheric 
CO2 concentrations, currently above 400 parts per mission, 
to 350 parts per million or below.5, 14 This CO2 
level would largely restore Earth's energy balance, keeping 
temperatures within the Holocene range to which human societies, 
agriculture, and other species are adapted. This could be achieved by 
limiting total cumulative fossil fuel emissions to 500 GtC coupled with 
cumulative negative emissions equivalent to 100 GtC by 2100.\4\ Hansen, 
et al.,\4\ identify two major ways that land management can achieve a 
100 GtC drawdown this century: (1) negative emissions from forest and 
soil carbon storage including reforestation and improved agricultural 
practices, and (2) avoided emissions from ending deforestation and 
deriving bioenergy from dedicated energy crops that do not compete with 
food crops. I agree these strategies have the potential to produce that 
quantity of negative emissions and both are discussed in more detail, 
below.
    Ocean and land sinks today remove from the atmosphere about half of 
the CO2 emitted by anthropogenic activities, or 4.9 GtC 
annually for the 1990-2000 period.\10\ About \1/3\ of the emitted 
CO2, 2.6 GtC for this period, is removed by land sinks.\10\ 
In the U.S., land sinks remove annually 0.2 GtC.11 Negative emissions 
as discussed here are in addition to these existing natural sinks.
3.0  Soil Carbon Cycling and Storage
    Carbon accumulates naturally during soil development as plants 
colonize new substrates such as sand and rock surfaces, transform 
atmospheric CO2 to new biomass via photosynthesis, and then 
leave behind carbon-rich leaves, wood, roots, and other biomass that 
then decompose. Some plant parts decompose quickly, others more slowly. 
Wood, for example, is very resistant to microbial attack, and some of 
the natural carbon products that are highly resistant to microbes can 
persist for thousands of years. Soil organic carbon can also be trapped 
within soil aggregates, which are hardened clusters of soil particles 
(grains of sand, silt, and clay) wherein very low oxygen levels inhibit 
microbial activity. And some decomposition products, usually in the 
form of complex organic molecules, can be highly resistant to decay 
especially when bound to soil mineral surfaces.
    Over time, most soils accumulate organic carbon to some equilibrium 
value that represents a few percent of total soil mass; in most soils 
this value is less than 5%. In waterlogged or cold soils such as those 
under bogs and tundra, decomposition occurs very slowly-microbial 
activity is suppressed by low oxygen or low temperatures or both--and 
in these locations, carbon can accumulate to very high proportions of 
soil mass.
    Soil thus contains organic carbon of different ages and different 
susceptibilities to microbial decomposition. Soil disturbance--both 
natural and anthropogenic--can stimulate decomposition by altering the 
soil physiochemical environment. Clearing land for agriculture does 
exactly this: plowing the soil breaks apart aggregates and exposes 
protected carbon to microbial attack, and allowing soil to remain bare 
for much of the year causes it to be wetter and warmer--perfect 
conditions for microbes to convert soil organic carbon back to 
CO2 in their quest for energy. Almost everywhere, conversion 
of native forest and grassland soils to agriculture results in a 30-50% 
loss of carbon from the top soil layers within just a decade or 2 
(Figure 2),\15\ a general pattern well-recognized since the 19th 
century.\16\ Global estimates of this loss total 133 GtC, split nearly 
evenly between crop and grazing lands.\17\
Figure 2


          Changes in soil organic matter fractions following 
        cultivation of a soil profile undernative vegetation. Redrawn 
        from Grandy and Robertson (2006).\26\

    The basis for soil carbon gain is thus the net balance between 
photosynthesis, which fixes CO2 into biomass carbon, and 
decomposition, which transforms biomass carbon back to CO2. 
Thus the organic carbon content of soils is regulated by the balance 
between the rate of carbon added to soils from plant residues (both 
aboveground biomass and roots), plus, in agricultural soils, organic 
amendments such as compost and manure, and the rate of carbon lost from 
soil, mainly via decomposition, though soil erosion can be locally 
important.
3.1  Measuring Soil Carbon Storage
    The total amount of organic carbon in a soil sample can be measured 
by a variety of techniques, most reliably by thermal oxidation.\18\ 
Historically, carbon has been assessed by combusting a small soil 
sample at temperatures sufficient to convert organic carbon to 
CO2. This generally entails placing a soil sample of known 
weight into a high-temperature furnace for several hours; the 
difference in mass on re-weighing represents oxidized carbon and by 
difference, the carbon content of the soil prior to combustion. A 
variation on this technique uses a chemical oxidizing agent rather than 
direct heat to combust the carbon. Today soil carbon is most commonly 
analyzed by gas chromatography: an automated sampler drops a tiny 
amount of ground, well-mixed soil into an oxygen-infused chamber that 
is subsequently ignited; the CO2 liberated is then measured 
by gas chromatography or infrared gas absorption analysis.\19\ Data 
from samples so analyzed can be used with high confidence; identical 
samples typically vary no more than 5-10%.
    Due to the natural variability of soil at even small scales, most 
field experiments to document the effects of a management practice on 
soil carbon typically compare practices for similar slope positions, 
and often in replicated small plots, in order to detect differences 
with statistical confidence. Even so, to dependably detect soil carbon 
change typically requires a decade or more \20\ because change occurs 
slowly such that it is much easier to detect with confidence a 10% 
carbon change over 10 years that a 1% change over 1 year. Thus, both 
long-term sampling and experiments are important for assessing changes 
in soil carbon.
    Soil carbon also varies with depth in the soil profile, so it is 
also necessary to design sampling programs to directly compare similar 
depths. Typically, the upper few cm of soil contain the most carbon, 
with concentrations falling rapidly in lower layers. Lower subsoil 
carbon concentrations plus its greater natural variability make it 
especially difficult to detect soil carbon change in lower 
horizons.\21\ Thus, most of what we know about the effects of land 
management practices on soil carbon stores comes from changes in 
surface horizons,\22\ typically the upper 25-30 cm where most root 
growth and biological activity occurs.
3.2  Soil Carbon Gain by Improved Land Management
    Soils globally contain 1,800 GtC to 1 m depth, comprising the 
largest terrestrial organic carbon pool and representing about twice 
the amount of carbon that is in the atmosphere (830 GtC). Soils of the 
conterminous U.S. contain 81 GtC to 1 m depth.\23\ Thus a relatively 
small percentage increase in soil carbon represents a potentially 
strong climate change mitigation opportunity.\24\
---------------------------------------------------------------------------
     This includes soils on both Federal and private lands in the 
lower 48 United States.
---------------------------------------------------------------------------
    Soil carbon stocks can be increased by increasing the rate of 
carbon additions to soil or by decreasing the rate of decomposition, or 
both. Croplands and grazing lands can be managed for enhanced carbon 
gain, but for each there are limits to the extent of gains possible. 
First, with changes to soil management that lead to carbon gain, soil 
carbon stocks tend towards a new equilibrium asymptotically, such that 
gains diminish as the new equilibrium level is approached, usually over 
a few decades (Figure 2).\25\ Second, this equilibrium level is finite 
for a given soil at a given location: soils tend to have a saturation 
level above which no further soil carbon increase is likely 
possible.\26\ Furthermore, if this equilibrium is reached because of 
high exogenous inputs such as compost or manure, cessation of these 
inputs will lead to a new, lower equilibrium.\27\
    Nevertheless, almost all soils in the U.S. actively managed for 
agriculture, as well as those that have been abandoned from agriculture 
due to degraded fertility, have soil carbon levels well below 
saturation, providing significant opportunities to manage for 
additional carbon. Cropland surface soils of the central U.S. are 
believed to have lost 50% of their pre-cultivation carbon stocks by 
1950.\28\
    A number of agricultural practices have the potential to increase 
soil carbon. In most cases these practices differ by management system: 
practices for croplands are different from practices for grazing lands 
and both are different from practices for managed forests. 
Nevertheless, the principles in all cases are the same, and some 
practices can be applied across systems. Practices below are grouped 
into three categories: those relevant to cropland and grazing lands 
management, wetlands restoration, and forest management.
    In Section 5, below, the total potential impact for the U.S. (GtC) 
is estimated based on the average likely carbon gain (GtC 
ha-1 yr-1) for a given practice multiplied by the 
areal extent (acreage) on which the practice could be implemented, and 
then again by the number of years between 2020 and 2100 that the 
average gain might persist. In some cases, multiple practices could be 
implemented on the same lands--many cropland management practices, for 
example, such as no till adoption and diversified crop rotations. In 
other cases, practices are mutually exclusive--cropland management 
practices, for example, cannot be applied to set-aside cropland 
converted to perennial grasses. And some practices are already 
implemented to limited degrees.
    Areal extents of potential practices are thus additional to any 
existing implementation, and are intentionally conservative in order to 
avoid the likelihood of double counting. The maximum extents possible 
are, of course, constrained by available land area; all private and 
public lands within the conterminous U.S. (the lower 48 states), on 
which Section 5 estimates are based, contains 159 Mha of cropland, 265 
Mha of rangeland and pasture, and 256 Mha of forest lands.\29\
    About 43% of total rangeland and pasture30 and 42% of total forest 
land \31\ in the conterminous U.S. are owned by the Federal Government 
and thus practices could be implemented directly. On privately held 
lands practices can be encouraged through financial incentives such as 
tax abatements or direct payments, used since the 1930s to advance 
national conservation goals. In 2017, for example,\32\ the USDA spent 
$2.0 billion for the Conservation Reserve program, which kept 9.4 Mha 
of environmentally sensitive land set aside from production, including 
0.8 Mha of restored wetlands; $2.8 billion for the Environmental 
Quality Incentives Program and the Conservation Stewardship Program, 
which provide landowners conservation assistance to reduce soil erosion 
and enhance water, air, and wildlife resources on crop and grazing 
lands; and $0.5 billion for the Agricultural Conservation Easement 
Program, which helps to conserve grazing and wetlands in particular. 
Other than fire suppression, minor assistance was provided to private 
forest landowners, chiefly through the $0.02 billion Forest Stewardship 
program.
    The duration of a given practice's carbon gain is likewise 
constrained by the average amount of time it takes the sink, whether 
soil or trees, to reach local equilibrium. For soils this will vary 
mainly by climate, management, and initial carbon content--for example, 
a degraded or long-cultivated soil will take longer to equilibrate than 
will a soil closer to its original carbon content. For trees this will 
vary mainly by location, species, and soil fertility--for example, 
trees in the Rocky Mountains grow more slowly than trees in the Pacific 
Northwest, and red pine grows faster than Douglas fir. On the other 
hand, the duration of avoided emissions is not constrained by biology--
the emissions reductions will persist for as long as the practice 
persists.

    3.2.1  Cropland Management

    Cropland Management: Tillage

    Farmers plow to control weeds, manage residues, and prepare the 
seed bed for planting. Plowing also causes carbon loss by mixing plant 
residues throughout the surface soil, bringing it into contact with 
microbes and other soil organisms like earthworms, and with moister 
soil more favorable to microbial activity. Plowing also breaks apart 
soil aggregates, especially the larger ones, exposing trapped organic 
carbon to aerobic microbes that readily respire it to 
CO2.\33\ In fact much of the early increase in atmospheric 
CO2 starting in the 19th century was the result of pioneer 
cultivation,\34\ which stimulated microbial activity and the conversion 
of soil organic matter to CO2.
    Modern advances in tillage technology provide many more options 
than traditional moldboard plowing, which inverts the upper 20-30 cm of 
soil. Contemporary lower-impact options, typically termed conservation 
tillage, range from chisel plowing, which avoids inverting the soil 
profile, to no till, which leaves the soil profile completely 
undisturbed. With no till, weeds are usually suppressed with herbicides 
or, at smaller scales, with cover crops and mechanical crimping, and 
seeds are planted with equipment that places seeds in slits cut through 
the preceding crop's residue, which is left to decompose on the soil 
surface rather than buried. Both of these practices can significantly 
increase the amount of carbon stored in the soil.
    The primary impetus for the development of no-till and other 
conservation tillage techniques was erosion control.\35\ Under no-till 
corn, for example, erosion can be reduced as much as 90% 
36-39 by reducing the exposure of soil aggregates to 
raindrop impacts and to freeze-thaw and wet-dry cycles, allowing more 
to remain intact, protecting entrapped carbon from microbial oxidation 
to CO2.\40\ And plant residue, by remaining on the soil 
surface, decomposes more slowly.\41\
    Carbon accumulation due to no-till has been documented in soils 
worldwide, including the U.S. since the 1950s.\35\ Long-term field 
experiments comparing no-till to conventional tillage show typical no-
till increases of 0.1-0.7 tC ha-1 
yr-1.42, 43 West and Marland \44\ estimated 
average rates of 0.3 tC ha-1 yr-1, a rate 
consistent with other syntheses 45-48 including Eagle, et 
al.'s,\48\ who included the impact of nitrous oxide emissions in their 
overall estimate. Where soil carbon is already high, no-till has less 
capacity to increase soil carbon; no till also has less capacity to 
increase soil carbon in cooler or wetter areas where it can sometimes 
reduce crop yield.\49\ Other forms of conservation tillage can also 
build soil carbon but at lower rates and less consistently.\50\
    Importantly, to achieve a long-term increase in soil carbon from 
no-till practices, the no-till practices must be implemented 
continuously. Stored soil carbon can be quickly oxidized to 
CO2 when no-till soils are tilled,15, 51 with 
much of the no-till carbon benefit lost after a single tillage 
event.\52\ Thus, while no-till is practiced on as much as 36% of U.S. 
soils annually, because it is practiced at least 3 years in a row on 
less than 13% of U.S. cropland,\53\ and almost certainly less on a 
permanent basis, there presently is little long-term climate benefit. 
Efforts to use no-till as a negative CO2 emissions strategy 
must consider no-till longevity an important design component.
    An exception to this continuous long-term no-till rule is the 
potential for burying surface soil carbon with a single inversion 
tillage. In humid climates with poorly drained soils, a one-time deep 
inversion tillage may promote soil carbon storage by moving high-carbon 
surface soils to >50 cm depth, where decomposition is slowed due to 
cooler, wetter conditions with less oxygen. At the same time, low 
carbon soil at depth is moved to the surface where it can accumulate 
more carbon. In one of the only long-term deep tillage experiments, 
Alcantara, et al.,\54\ found carbon accumulation rates equivalent to 1 
tC ha-1 yr-1 in Germany.
    A further consideration is the potential for soil carbon to change 
at depths below the top soil horizon. Almost all quantitative 
assessments of no-till to date have assessed changes in soil carbon in 
the upper 25-30 cm of the soil where roots, soil organic matter, and 
microbes are most concentrated. However soil carbon also occurs at 
lower depths,\17\ and there is the potential,22, 55 but 
little quantitative evidence,21, 56 for soil carbon changes 
at depth to counteract surface soil gains in some locations.
    Although carbon savings associated with no-till also accrue from 
reduced fuel use due to fuel saved by not plowing, this saving is 
typically small (typically <0.05 tC ha-1 
yr-1),44, 57 though permanent in that it is not 
subject to re-release like stored soil carbon.

    Cropland Management: Summer Fallow and Winter Cover Crops

    In most annual cropping systems soils are left bare for a 
substantial portion of the year. Without plants, soils lose carbon 
because there are fewer carbon inputs from roots and aboveground 
residues and because decomposition rates are higher--soils are wetter 
and warmer without plant transpiration and shading.\58\ For most annual 
crops in the U.S. (e.g., corn, soybean, cotton, sorghum, peanut, and 
vegetables) the fallow period occurs over winter, stretching from mid-
fall to late-spring (5-7 months). For fall-planted crops like winter 
wheat and winter canola, the fallow period occurs over summer and lasts 
from the mid-summer harvest to at least late fall (3 months), or, 
where followed by a summer crop, to the following spring (9-10 months). 
Thus for most U.S. cropland the soil is bare for much of the year. In 
semi-arid regions summer fallows are often used to conserve soil 
moisture for a following crop.
    Eliminating summer fallow periods can, in the U.S., sequester up to 
0.3 tC ha-1 yr-1 of soil carbon depending on 
climate and tillage method. Eagle, et al.,\48\ estimated an average 
soil carbon gain of 0.16 tC ha-1 yr-1. Less the 
CO2 cost of the additional nitrogen fertilizer used reduces 
the net benefit to 0.09 tC ha-1 yr-1. Where 
summer fallow is used for water conservation, summer fallow cannot 
likely be eliminated but could be used less frequently, such as every 
third or fourth year instead of every second or third 
year.59, 60
    Winter cover crops include annual grasses such as rye and legumes 
such as clover that are typically planted in the fall following harvest 
of the preceding crop. Prior to winter the cover crop germinates and 
grows to a size that allows it to survive wintertime temperatures in a 
dormant state, after which it grows rapidly the following spring. 
Before planting the following summer crop, the cover crop is killed and 
then either left to decompose on the soil surface or, more commonly but 
not necessarily, buried with tillage. Adding winter cover crops to a 
rotation can add 0.03-0.55 tC ha-1 yr-1 of soil 
carbon,61, 62 depending on climate, even when the cover crop 
is tilled under--providing in many cases a carbon gain equal to no-
till.\63\
    Winter cover crops provide the additional co-benefit of reducing 
the need for nitrogen fertilizer due to their ability to scavenge the 
previous crop's leftover soil nitrogen that would otherwise be leached 
to groundwater or emitted to the atmosphere, and, in the case of legume 
cover crops, the ability to capture or ``fix'' nitrogen from air. This 
captured or new nitrogen is then made available to the next crop, 
reducing the need to apply fossil fuel-derived nitrogen fertilizers, 
thereby creating additional carbon savings by avoiding one of the most 
significant sources of greenhouse gases in intensively managed field 
crops.\64\
    A recent meta-analysis \65\ estimates average carbon sequestration 
potentials for winter cover crops of 0.32 tC ha-1 
yr-1 globally, with a number of studies reporting rates as 
high as 1 tC ha-1 yr-1. Including fertilizer 
savings, Eagle, et al.,\48\ estimate a net potential carbon benefit of 
0.37 tC ha-1 yr-1 for winter cover crop use in 
the U.S., not including CO2 and nitrous oxide savings from 
reduced nitrogen fertilizer use, which they estimate could add another 
0.16 tC ha-1 yr-1 of carbon savings. Poeplau and 
Don's \65\ analysis suggest a new soil carbon equilibrium is reached 
after 155 years; \9\ the reduced CO2 and nitrous oxide 
savings from reduced nitrogen fertilizer use, where it occurs, would 
last indefinitely. For a variety of reasons, including additional seed 
and labor expenses as well as the risk of not killing the cover crop in 
a timely manner, cover crops are planted today on only 3% of U.S. 
cropland.\66\

    Cropland Management: Diversifying Crop Rotations

    Crop species vary in the amount of biomass they produce, in the 
proportion of biomass that goes unharvested, including roots, and in 
the resistance of unharvested residue to decomposition. Thus, 
diversifying crop rotations is a time-tested means to build and retain 
soil carbon. In the U.S. as early as 1933 Salter and Green \67\ 
reported on a 31 year experiment in which more complex rotations 
retained more soil carbon. In central Ohio they found that continuous 
corn (corn planted year after year) lost three times more soil carbon 
than did a 3 year corn-wheat-oats rotation; continuous wheat and 
continuous oats similarly lost twice as much carbon as did the 3 year 
rotation (Figure 3).
Figure 3


          Rotation effects on soil carbon maintenance over a 31 year 
        experiment. Redrawn from Salter and Green (1933).\58\

    Diversifying annual crop rotations can thus significantly increase 
carbon stores.50, 60, 68 The addition of perennial species 
such as hay and alfalfa to annual crop rotations, because of the deep 
and persistent roots of perennial crops and their longer growing 
season, can boost soil carbon still further,\42\ as can the inclusion 
of legumes such as clover.\69\ Measurements of soil carbon change under 
more diverse annual cropping systems range from 0.02 to 1.1 tC 
ha-1 yr-1,46, 50, 70, 71 but results 
are highly dependent on associated full-rotation changes in crop 
residues, tillage, and other factors that affect soil carbon stores. In 
consideration of these unknowns, Eagle, et al.,\48\ estimate an average 
net carbon benefit of 0.05 tC ha-1 yr-1 for 
diversifying crop rotations to a sequence more complex than corn--
soybean, mainly achieved by lower nitrous oxide emissions.

    Cropland Management: Manure and Compost Addition

    Organic materials such as compost and manure, when added to 
productive soils, tend to increase soil carbon stocks only as long as 
additions are sustained.\27\ Added to less productive soils, however, 
benefits can persist because of their additional impact on soil water 
holding capacity, porosity, aeration, infiltration, and nutrient 
holding capacity. These soil fertility co-benefits can increase crop 
productivity and subsequent residue inputs. Thus, while the climate 
benefit of moving compost or manure from one part of the landscape to 
another must be considered,\72\ where soil fertility is sufficiently 
improved to increase productivity the soil carbon gain is a legitimate 
and persistent climate benefit.
    In one recent example, Ryals, et al.,73, 74 added 
compost to rangeland, which, exclusive of carbon in the compost 
addition itself, appeared to increase soil carbon storage by 25-70% or 
0.51-3.3 tC ha-1 3 years after a single compost 
addition.\74\ Where manure is derived from crop harvest, which is the 
case for most dairy and feed-lot cattle in the U.S., its return to soil 
can be considered another form of crop residue return and thus also a 
climate-legitimate carbon gain when compared to business-as-usual 
practices. Estimates of soil carbon gain from long-term applications of 
livestock manure to arable soils range from 0.2 to 0.53 tC 
ha-1 yr-1.75, 76 Eagle, et al.,\48\ 
estimate a range of 0.05 to 1.4 for an average of 0.71 tC 
ha-1 yr-1 that does not include CO2 
savings from reduced nitrogen fertilizer use. Sequestration will likely 
continue for the duration of manure additions, in our case >80 years--
the world's longest-running manure addition experiment has found soil 
carbon stocks still increasing after 120 years,\77\ though stocks will 
equilibrate to some lower level upon cessation.77, 78

    3.2.2  Cropland Conversion to Perennial Grasses

    Cropland Conversion: Set-aside Highly Erodible Cropland

    Converting degraded or highly erodible cropland to perennial 
grasslands has the potential to sequester soil carbon insofar as 
perennial grasses have greater root carbon stocks than annual crops and 
because they are grown without tillage. Nevertheless, such conversions 
must be planned carefully to result in a legitimate climate benefit: 
Converting annual cropland to perennial grassland has no climate 
benefit where equivalent food production must be made up by more 
intensive crop production elsewhere, especially if such displaced crop 
production causes deforestation.\79\ Indirect land use change effects, 
while disputed by some,\80\ are undoubtedly possible and can 
potentially exceed local carbon savings.\81\
    Nevertheless, USDA conservation programs that pay farmers to 
convert privately-owned annual cropland with conservation value (e.g., 
highly erodible land) to grasslands or trees can lead to significant 
soil carbon savings as a valuable co-benefit. For example, around 9 Mha 
are currently enrolled in the U.S. Conservation Reserve Program, down 
from a high of 15 Mha in 2007.\82\ Sperow, et al.,\83\ estimate that an 
additional 30 Mha could be added to the 9 Mha currently enrolled based 
on a USDA erodibility index.
    Several recent reviews of soil carbon gain on conversion of annual 
grain to perennial grasses report average carbon sequestration 
potentials that range from 0.28-1.3 tC ha-1 
yr-1.84-87 Including the upstream savings from 
reduced agronomic inputs and nitrous oxide emissions (but not fossil 
fuel carbon offsets), Eagle, et al.,\48\ estimate an average carbon 
benefit of 0.97 tC ha-1 yr-1.

    Cropland Conversion: Cellulosic Bioenergy on Grain Ethanol Lands

    Where annual crops are currently used for grain-based biofuel 
production, conversion to dedicated cellulosic feedstocks such as 
perennial grasses could likewise sequester soil carbon and in this case 
without potential indirect land use change effects. Cellulosic 
feedstocks would additionally provide greater life cycle carbon savings 
than the grain-based feedstocks they would replace.\88\ In 2017 38% of 
total U.S. corn acreage, or 13 Mha, was used for grain ethanol 
production; \89\ converting this cropland to a perennial cellulosic 
crop would result in carbon savings additional to those from no-till 
conversion (assuming conversion from no-till to avoid double counting 
the no-till and perennial conversion benefits).
    The rate of soil carbon gain for annual cropland converted to 
perennial biofuel crops would be similar to that for set-aside cropland 
(0.97 tC ha-1 yr-1). This assumes little of the 
converted annual cropland was under permanent no-till management (see 
Section 3.2.1, above).

    Cropland Conversion: Cellulosic Bioenergy on Former Cropland

    The potential for additional mitigation from planting marginal 
lands--former cropland now abandoned--to cellulosic biofuel crops is 
also significant. Additional to the fossil fuel offset benefit is the 
soil carbon gain, especially on soils abandoned due to low fertility. 
Again, placement of such crops would need to avoid land with 
significant standing carbon stocks such as forests and wetlands to 
achieve a short-term climate benefit. Robertson, et al.,\88\ note that 
about 55 Mha of the 70-100 Mha of cropland abandoned since 1900 that is 
neither forest nor wetland would be needed to meet expected 2050 
biofuel needs.\90\ Planting these lands to higher productivity grass 
species would cause carbon accumulation additional to that already 
occurring in these lands.
    The rate of soil carbon gain for former cropland converted to 
perennial biofuel crops would be similar to that for set-aside cropland 
but discounted by the carbon gain already occurring under existing 
unmanaged vegetation.\88\ Assuming that the managed grasses are about 
twice as productive as the pre-existing vegetation, the discounted 
credit is likely to be 50% of the grassland conversion credit of 0.97 
tC ha-1 yr-1, or 0.48 tC ha-1 
yr-1. This value does not include a fossil fuel offset 
credit.

    3.2.3  Grazing Lands Management

    Grazing Lands Management: Improved Animal Stocking Rates

    Grazing lands, whether planted pastures as are typical in the 
eastern U.S., or extensive rangelands as are typical in the western 
U.S., are dominated by perennial grasses managed without annual 
tillage. Soil carbon stores can be improved significantly by increasing 
plant productivity via improved attention to livestock stocking 
rates.86 On rangelands, estimates of soil carbon increases resulting 
from improved stocking rates range from 0.07 to 0.31 tC ha-1 
yr-1,91, 92 with higher rates for the Rocky 
Mountains and Great Plains region. In a new meta-analysis of some 50 
studies, Conant, et al.,\86\ estimate an average soil carbon 
sequestration potential for improved stocking management on extensive 
rangelands of 0.28 tC ha-1 yr-1. Because of a 
relatively low sequestration rate, time to equilibration will likely 
exceed 80 years.
    On pasturelands, Eagle, et al.,\48\ note the potential for 
intensive rotational grazing to improve soil carbon storage due to 
increased plant productivity and careful attention to stocking rates. 
The average sequestration rate for the few available published studies 
is 0.25 tC ha-1 yr-1.

    Grazing Lands Management: Improved Plant Species Composition

    Grazing lands carbon sequestration can also be increased by 
improving grass species composition. Interseeding legumes such as 
alfalfa on rangeland \93\ can increase long-term carbon accrual by 3.1 
tC ha-1 yr-1, and interseeding improved grass 
species can improve average soil C by similar amounts.\94\ Eagle, et 
al.,\48\ estimate an average soil carbon gain of 0.40 tC 
ha-1 yr-1 for improved species composition on 
rangelands. Henderson, et al.,\95\ estimate an average gain of 0.56 tC 
ha-1 yr-1 for planting legumes in pastures, even 
after decrementing rates for increased nitrous oxide emissions.

    3.2.4  Frontier Technologies

    There are unconventional technologies also under study for 
increasing carbon removal and storage through agricultural land 
management practices, some more mature than others. While these 
practices may eventually prove to increase the carbon sequestration 
potential within the U.S., I do not include these technologies in my 
quantitative assessment of negative emissions because their feasibility 
and benefits are yet too uncertain. The technologies include, but are 
not limited to:

  (1)  Very high animal stocking rates on extensive rangeland for short 
            periods of time, known by a number of names including 
            intensive rotational grazing (as for pasturelands) and mob 
            grazing, have shown promise for improving productivity and 
            soil carbon stocks. In at least one study additional soil 
            carbon accumulation was 3 tC ha-1 
            yr-1 compared to continuous grazing.\96\ These 
            results are too early to generalize, however,\97\ and 
            recommendations await the results of further 
            experimentation.

  (2)  Biochar additions to soils have shown, in many cases, a 
            propensity to increase long-term soil stocks via direct 
            carbon stock change and improved soil fertility that, like 
            compost, can boost productivity in degraded or infertile 
            soils. Biochar is charcoal: a pyrolysis byproduct of the 
            thermochemical conversion of wood to other energy products 
            such as biogas and liquid bio-oil.\98\ Most biochar is 
            highly resistant to microbial attack, and additions to a 
            wide variety of soils have demonstrated its general 
            tendency to persist-indeed, many soils of fire-prone 
            ecosystems in the U.S. contain substantial amounts of 
            natural biochar.\99\

    But biochar additions can also enhance the decomposition of native 
soil organic matter,100, 101 offsetting the soil carbon 
benefit of biochar itself, and as well biochar may be of greater 
mitigation value if converted directly to energy to offset fossil fuel 
use.\8\ A biochar recommendation awaits further research to clarify 
both the long-term soil carbon gain in field studies and life cycle 
carbon analysis in comparison to alternative uses.

    3.2.5  Wetlands Restoration

    Wetlands Restoration: Histosols

    Histosols are soils high in organic matter due to their formation 
under waterlogged conditions that inhibit microbial activity. As 
wetland plants such as sphagnum moss produce biomass, a significant 
fraction accumulates as peat and high-carbon sediments. When drained 
for agriculture, histosols tend to be extremely productive, but once 
exposed to oxygen, microbial activity accelerates and histosols can 
lose carbon quickly at rates as high as 20 tC ha-1 
yr-1.\102\ About 8% of histosol soils in the U.S. have been 
drained for agriculture, mostly in Florida, Michigan, Wisconsin, 
Minnesota, and California.
    Carbon accumulation in these soils can be restored (carbon loss 
reversed) by taking them out of production and restoring the high water 
table. Although restoring wetland conditions will also restore methane 
production, the combination of reversed carbon loss and abated nitrous 
oxide emissions usually will exceed the additional methane loss, 
leading to a large net emissions reduction.\103\ However, the area of 
cultivated histosols soils is relatively small in the U.S.--used mostly 
for vegetables and sugar cane production--so the overall mitigation 
potential is modest.\24\ And as for cropland conversion to perennial 
grasslands, care must be taken to avoid indirect land use change 
effects. In 2017, the USDA paid farmers to maintain 0.8 Mha of restored 
wetlands \32\ through the Farmable Wetlands Program (https://
www.fsa.usda.gov/programs-and-services/conservation-programs/farmable-
wetlands) within the Conservation Reserve Program (see Section 3.2); at 
least another 0.8 Mha is readily available.\48\
    Estimates of carbon gain under restored histosols vary widely, from 
0.6 to 20 tC ha-1 yr-1.48 An average value, 
considering other greenhouse gas impacts such as increased methane 
emissions, was estimated by Alm, et al.,\104\ to be around 2.7 tC 
ha-1 yr-1 for Finnish peatlands; more recently 
Griscom, et al.,\9\ suggest an average value from a global peatlands 
database of 3.65 tC ha-1 yr-1.

    Wetlands Restoration: Non-Histosols

    A substantial fraction of non-histosol wetlands have been drained 
for agriculture in the U.S., and despite being below the threshold for 
definition as histosols, prior to agricultural conversion they 
generally had higher soil organic matter content than well-drained 
soils. About 80% of wetland drainage in the U.S. has been attributed to 
agriculture, or 32 Mha since 1780. Estimates of soil carbon 
accumulation upon restoration are highly uncertain but in the range of 
0.41 tC ha-1 yr-1,\105\ much smaller than for 
histosol wetlands with their substantially greater soil carbon content, 
and in the range that could be offset by increased methane emissions. 
Thus it is not yet clear whether non-histosol wetland restoration is an 
effective carbon sequestration strategy.

    3.2.6  Forest Management

    Forests, like croplands and grazing lands, can be managed to 
enhance carbon sequestration via changes to forestry practices or by 
conserving standing forests. Generally forest management includes 
reforestation, which refers to the reestablishment of trees following 
forest harvest, but does not include afforestation, defined by IPCC 
\105\ as the establishment of trees on lands that have been deforested 
for 50 years or more. In the U.S., afforestation largely comes at the 
expense of current crop and pasturelands \106\ and thus will create 
indirect land use change effects elsewhere, likely resulting in little 
if any net climate benefit.107, 108 About 42% of total 
forestland in the conterminous U.S. is publicly owned and managed by 
Federal agencies.

    Forest Management: Improved Stand Management

    Improved forest management designed to enhance carbon sequestration 
in tree biomass includes choices of tree species (fast versus slow 
growing), harvest age or rotation length, and the use of practices such 
as fertilization, controlled burning, and thinning to increase forest 
productivity and carbon storage. Delaying rotation increases carbon 
storage because carbon continues to accumulate as the trees grow; 
109, 110 even relatively old growth forests continue to 
accumulate carbon in soil stocks, including carbon in slow-to-decay 
fallen trees on the forest floor.111, 112 But even without 
additional carbon sequestration, preservation of an existing forest 
biomass stock keeps it from the atmosphere for the period delayed.
    Rotation lengths differ regionally by tree species and ownership 
and can be managed readily. Softwoods and mixed species in 
nonindustrial private forests of the southern U.S. are typically 
managed on rotations of 25 to 35 years or longer, although rotations in 
commercial forestry may be half this length.\113\ In the western U.S., 
commercial rotations tend to be 45-60 years because of longer-lived 
species.
    Delaying harvest and converting unmanaged forests to faster-growing 
species to increase forest productivity can sequester, on average, 1.4-
2.1 tC ha-1 yr-1.113, 114 Using an 
economic model, the U.S. Environmental Protection Agency (EPA)106 
estimated that 7-105 MtC yr-1 (0.07-0.105 Gt C 
yr-1) could be stored by all forests in the conterminous 
U.S. at carbon prices from $1 to $50 per tCO2 for 100 years 
or more; at a conservative $15 per tCO2,\8\ this amounts to 
60 MtC yr-1. Their variable price economic model yields a 55 
MtC yr-1 average by mid-century, which is consistent with 
Griscom, et al.'s,\9\ U.S. projection of 18 MtC yr-1, not 
including planted forests nor fire management, which they consider 
alone could avoid 11 tC ha-1 yr-1 of carbon loss 
in fire-prone forests such as those in the western U.S.
    Reforestation, not considered here because of overlap with marginal 
lands included in cellulosic biofuel estimates (Sections 3.2.2 and 
4.2.4), could also provide substantial negative emissions. Griscom, et 
al., project potential sequestration of 98 MtC yr-1 were all 
once-forested U.S. pastureland, mostly east of the Missouri River and 
including lands currently grazed, reforested. Such a strategy, however, 
would require diet shifts away from meat to avoid indirect land use 
effects, whereby displaced food production results in conversion of 
natural areas (with its carbon loss) elsewhere, such as Amazonia. On 
the other hand, reforestation on marginal lands not used for grazing 
could provide carbon benefits similar to conversion to cellulosic 
biofuels once biofuels were no longer used for fossil fuel 
displacement.\115\

    Forest Management: Improved Soil Management

    Soil carbon stocks in U.S. forests are, in aggregate, substantial; 
\116\ about 50% of the carbon in U.S. forests is in the soil and 
another 8% in detrital material on the forest floor.\117\ Various 
activities can affect forest soil carbon storage: rotation length, 
harvest intensity, and fire management are among the most important. 
Kimble, et al.,\117\ estimate that in total, U.S. forests managed for 
timber could sequester 25 to 103 MtC yr-1 (0.25-0.103 GtC 
yr-1), for average sequestration rates of 0.12-0.51 tC 
ha-1 yr-1, or a mean of 0.32 tC ha-1 
yr-1, a more conservative rate than earlier IPCC \105\ 
estimates for temperate forests of 0.53 tC ha-1 
yr-1. This sequestration would be additional to the current 
U.S. forest soil background sink recently estimated \118\ at 13-21 MtC 
yr-1. Kimble, et al.,\119\ further estimate that soils under 
agroforestry systems--e.g., alleycrops, riparian buffers, windbreaks, 
and urban forests--could sequester nationally another 17-28 MtC 
yr-1, or an average of 22.5 MtC yr-1.
4.0  Agricultural Greenhouse Gas Abatement by Land Management
4.1  Measuring Nitrous Oxide and Methane Fluxes
    Nitrous oxide and methane, like CO2, are naturally 
occurring greenhouse gases. They are distinguished in part by their 
substantial global warming potentials, the degree to which they are 
responsible for radiative forcing of the atmosphere compared to 
CO2. Over a 100 year time horizon, nitrous oxide has 265-300 
times the global warming potential of CO2, and methane 28-
36.10, 120 Another way of thinking about global warming 
potentials is that 1 Mt of avoided nitrous oxide emission is equivalent 
to 265-300 Mt of sequestered CO2. Thus, though their 
atmospheric concentrations are substantially lower than those of 
CO2, they pack significant punch and concentrations of each 
have risen by about 45% since 1970.\1\ In order to directly compare the 
atmospheric impact of all three gases, emissions of nitrous oxide and 
methane are multiplied by 298 and 25, respectively,\102\ and expressed 
as CO2 or carbon equivalents (CO2eq or Ceq).
    Nitrous oxide is naturally emitted by bacteria in soils and other 
environments as a byproduct of their nitrogen metabolism. Some nitrous 
oxide is also emitted naturally from fires. Agriculture is responsible 
for 84% of anthropogenic nitrous oxide emissions,\121\ and most 
agricultural emissions (62%) come from soils amended with nitrogen from 
fertilizers, manures, or legumes. Thus a major mitigation opportunity 
related to land management is improved nitrogen fertilizer efficiency.
    Agricultural methane emissions come from enteric fermentation by 
livestock (52%), rice cultivation (22%), biomass burning (19%), and 
livestock manure handling (8%).\121\ From the standpoint of land 
management, rice cultivation offers today a substantial cropland 
mitigation opportunity where rice is grown.
    The non-CO2 greenhouse gas exchanges with the atmosphere 
(fluxes) are not easily quantified. Most of what we know comes from 
thousands of gas flux measurements made from small chambers (often 25-
30 cm diameter) placed on the soil surface. As gases accumulate in the 
chamber, over the course of an hour or 2 gas samples are withdrawn and 
analyzed for nitrous oxide or methane. The rates of gas accumulation 
are calculated from these samples and represent net emissions.\122\
    Like soil carbon, the spatial variability of fluxes from soil is 
very high. Consequently, evaluations of abatement by different 
agricultural practices are usually made in experimental plots to 
isolate the effect of the practice from natural soil variability. Such 
comparisons provide a high degree of confidence when they are made at 
appropriate times: unlike soil carbon stocks, gas fluxes are also 
highly variable in time. It's thus important to compare fluxes during 
periods of low fluxes and high fluxes, and sampling campaigns are 
expensive because of this need for frequent sampling. Nevertheless, 
nitrous oxide and methane fluxes have been measured in agricultural 
systems for over 40 years, and we have a reasonable understanding of 
the major factors that regulate fluxes and can identify a number of 
mitigation paths.
4.2  Avoided Emissions by Improved Land Management
    4.2.1  Reduced Nitrous Oxide Emissions from Field Crops

    About 50% of anthropogenic nitrous oxide emissions are from 
nitrogen-fertilized field crops such as corn and wheat, where natural 
soil bacteria that produce nitrous oxide are stimulated by more 
available soil nitrogen. While factors other than fertilizer can also 
accelerate nitrous oxide production, it has been known from field 
studies since the 1970s 123-125 that nitrogen fertilizers 
are responsible for most agricultural nitrous oxide emissions (e.g., 
Figure 4). In fact, most IPCC national greenhouse gas inventories tally 
agricultural nitrous oxide emissions as a fixed percentage of nitrogen 
fertilizer use.126, 127 Recent evidence that N2O 
emissions increase exponentially with nitrogen fertilizer additions in 
excess of crop need 128, 129 places even more importance on 
fertilizer nitrogen rate as a predictor of agricultural emissions; this 
exponential increase is incorporated in both commercial greenhouse gas 
reduction protocols 130, 131 and in USDA protocols for 
quantifying farm-level emissions.\132\ These protocols are now being 
built into the COMET-Farm tool that allows farmers and ranchers to 
calculate the greenhouse gas impacts of current and projected 
practices.\133\
Figure 4


          Nitrous oxide (N2O) emission response to nitrogen 
        fertilizer. Redrawn from Brietenbeck, et al., (1980).\111\

    While other management interventions are also known to reduce 
nitrous oxide emissions at specific locations,\132\ reducing nitrogen 
fertilizer inputs to the rate needed for optimum yields (called by 
agronomists the economically optimum rate) is the most reliable means 
to reduce nitrous oxide emissions from fertilized cropping 
systems.\134\ Carbon equivalent savings for a 15-20% increase in 
fertilizer use efficiency (equivalent to a 15-20% reduction in average 
nitrogen fertilizer use) in rainfed crops range from 0.15 to 0.29 
tCeq ha-1 yr-1.103, 134-136
    Millar, et al.,\134\ used an optimum fertilizer rate calculator to 
show that nitrogen fertilizer rates on corn could be reduced for seven 
Midwest states by at least 15% without affecting yields. A 15% 
reduction represents an average avoided nitrous oxide emission of 2.2 
kg N2O ha-1 yr-1, equivalent to 0.18 
tCeq ha-1 yr-1 assuming a conservative 
emission factor of 0.017 kg of nitrous oxide nitrogen per kg of 
nitrogen fertilizer applied.\129\ In 2014 the U.S. consumed 13.3 Mt of 
fertilizer N; \137\ a 15% savings (2.0 Mt N) would additionally save 
15% of the CO2 cost of manufacture, equivalent to 2.2 MtC 
yr-1 (0.0022 GtC yr-1) at a fertilizer production 
cost of 4 kg CO2 per kg of nitrogen.\138\
    At midcentury, others 139, 140 project a 50% increase in 
nitrogen fertilizer use efficiency, from 53% today to 75% in the 
future. If implemented immediately, this would lead to a 32% reduction 
in nitrogen fertilizer use,\9\ for avoided nitrous oxide emissions of 
0.36 tCeq ha-1 yr-1 and avoided 
CO2 from fertilizer production of 2.2 Mt C yr-1. 
Cropland affected by this savings is assumed to be that planted to 
crops in 2012 (139 Mha) less the acreage in soybeans and peanuts,\141\ 
major commodity crops that require no nitrogen fertilizer.

    4.2.2  Rice Water Management for Methane

    Rice in the U.S. grows in flooded soils that create the oxygen-
depleted soil environment necessary for methane production. While rice 
is not a major cereal crop in the U.S., annual rice-related methane 
production is 3.1 GtCeq,\11\ about 2% of 2015 U.S. methane 
emissions and about 2% of total worldwide methane production from 
rice.\142\
    Methane from flooded rice is most readily controlled by periodic 
drainage. Sass, et al.,\143\ documented a 50% reduction in emissions in 
Texas with a single mid-harvest drainage, and almost complete cessation 
with a 2 day drainage every 3 weeks. Others have found similar 
responses around the world, particularly in China.\144\ Eagle, et 
al.,\145\ suggest a U.S. rice methane mitigation potential of 0.54 
tCeq ha-1 yr-1 based on improved 
drainage practices. Additional mitigation can be achieved with new 
high-yielding rice cultivars that increase root zone porosity and 
consequent methane oxidation.\146\

    4.2.3  Cellulosic Bioenergy Production on Grain Ethanol Lands

    As noted earlier, about 44% of U.S. corn acreage is currently used 
for grain-based ethanol production. Were this acreage turned to biomass 
production for cellulose-based ethanol production, using technology 
that is currently in commercial use in the U.S., the climate benefit of 
ethanol production would be substantially improved because the 
production of cellulosic biomass crops like switchgrass require very 
few fossil fuel inputs, unlike the production of corn grain. Whereas 
grain-based ethanol avoids only 18% of the CO2eq that would 
otherwise be emitted by gasoline, cellulosic ethanol avoids nearly 
90%.147, 148 Thus, substituting cellulosic feedstocks such 
as switchgrass on current corn grain ethanol cropland could provide a 
substantially greater fossil fuel offset than grain ethanol feedstocks, 
in addition to providing soil carbon sequestration as noted above in 
Section 3.2.
    The additional climate benefit can be calculated from a standard 
life cycle analysis model such as GREET.149, 150 Not 
including the soil carbon benefit already considered above, switchgrass 
with a conservative biomass yield of 8 Mg ha-1 
yr-1 can provide 1.44 tC ha-1 yr-1 of 
fossil fuel CO2 savings when converted to 
ethanol.150, 151 The difference from corn grain (0.73 tC 
ha-1 yr-1 for a grain biomass yield of 11 Mg 
ha-1 yr-1) represents a net avoided 
CO2 emission benefit of 0.71 tC ha-1 
yr-1. The difference would be greater with a higher yielding 
cellulosic biomass crop.

    4.2.4  Cellulosic Bioenergy Production on Marginal Lands

    Cellulosic biofuels can also be grown on former agricultural lands, 
as noted earlier. To meet expected 2050 liquid transportation fuel 
demands requires 55 Mha of the 70-100 Mha of crop and pastureland 
abandoned from agriculture since 1900, excluding urban, forest, and 
wetlands.\88\ Planting this acreage to switchgrass with an avoided 
CO2 emission benefit of 1.08 tC ha-1 
yr-1 for an average 6 Mg ha-1 yr-1 
yield 150, 151 would generate a significant avoided 
CO2 emissions savings. This value does not include the soil 
carbon sequestration included as negative emissions. Note that this is 
not BECCS, insofar as the carbon in the fuel is not geologically 
sequestered as CO2.
5.0  Total Mitigation Potentials
    Several published studies have estimated a total biophysical 
potential for soil carbon sequestration globally and in the United 
States with land management technologies that are currently available. 
Before summarizing the U.S. carbon mitigation potential it is worth 
considering the global perspective.
5.1  Global Estimates of Potentials for Soil Carbon Gain
    Recent global estimates of the biophysical potential for cropland 
and grazing land soils to sequester carbon range from 
0.4-1.5 GtC yr-1 (Table 
1).24, 105, 152-156 Each of the estimates in Table 1 assume 
adoption of some combination of improved cropland and grazing land 
management, agroforestry, and restoration of degraded lands and 
histosol wetlands. Note that they do not include other sequestration 
practices described above, including sequestration due to improved 
forest management and conversion of grain ethanol lands to cellulosic 
biofuel crops, nor savings from avoided emissions such as those from 
improved nitrogen fertilizer use. That these global estimates are 
similar to one another arises from considering the same types of 
practices and using similar well-constrained field estimates that are 
based on long-term experiments for major mitigation practices such as 
no-till.
    To calculate the total century-long mitigation potential requires 
knowing for how long these rates are sustainable. As noted earlier, 
soil carbon accumulation tends to behave asymptotically--after some 
period maximum rates slow until a new equilibrium is reached (Figure 
2). Although very long term experiments in agricultural systems are 
rare, it's clear that the applicable period likely differs among 
management practices, climate zones, and initial soil carbon levels. 
Many researchers assume conservatively that average maximum rates occur 
for at least 20 years with the rate of sequestration after then 
declining to a new steady state that occurs about 40 years post 
management change,28, 44 although some (e.g.,\152\) assume 
>50 years persistence. A 30 year period at average sequestration rates 
seems a reasonable working value and is the value I have used for the 
calculations contained in this report.

                                                                         Table 1
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Set-aside of
              Estimate        Improved         Improved         erodible      Restoration of                   Restored peat
   Year     (GtCeq yr	1)      cropland       grazing land     cropland to     degraded land    Agroforestry        soils               Reference
                             management       management       grassland
--------------------------------------------------------------------------------------------------------------------------------------------------------
   1998         0.4-0.9               X                                 X                X                                       Paustian, et al.\152\
   1999         0.5-0.6               X                                                  X                                                            Lal and Bruce \153\
   2000            0.82               X                X                X                                X               X                  IPCC \105\
   2004         0.4-1.2               X                X                X                X               X                                            Lal \154\
   2008         1.4-1.5               X                X                X                X                               X          Smith, et al.\103\
   2014         0.7-1.4               X                X                X                X               X                     Sommer and Bossio \156\
   2016         0.3-1.5               X                X                X                X               X               X        Paustian, et al.\24\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Published estimates of global soil carbon sequestration potentials based on biophysical processes that could be enhanced by land management actions. Not
  included are sequestration potentials from forest management, cellulosic biofuel crops, or carbon additions such as compost or biochar, nor savings
  from avoided emissions such as those from avoided nitrogen fertilizer use.

    If the average global sequestration rate of 1.2 GtC yr-1 
for the three most recent analyses 24, 155, 156 is 
multiplied by a conservative 30 year sequestration period, then we can 
calculate an end-of-century value of 36 GtC sequestered for this set 
of soil carbon practices.
    Expanding the scope to include forests and coastal wetlands readily 
boosts global negative emissions potentials well past the 100 GtC end-
of-century target for restoring a 350 ppm CO2 atmosphere.\4\ 
In one recent analysis Griscom, et al.,\9\ consider at the global scale 
20 conservation, restoration, and land management actions that, in 
aggregate, could sequester or avoid as much as 6.5 GtC yr-1 
for at least a 25 year period. They include aggressive reforestation, 
forest management, coastal wetland and peatland restoration, and Table 
1 practices to yield 169 GtC of negative emissions by the year 2100 if 
implemented soon. If reforestation were to more reasonably include 
reforesting only 25% of the once-forested areas, rather than 100%, 
their estimate reduces to 148 GtC by 2100.
    Avoided emissions, including stopping deforestation and wood fuel 
harvest, improved nitrogen fertilizer management, and avoided coastal 
wetland and peatland conversion provides another 128 GtC of savings, 
for a global end-of-century total of 276 GtC.
    It is worth emphasizing that these practices are feasible and 
available for implementation today, and would provide land-based 
CO2 mitigation additional to the existing 2.6 GtC 
yr-1 land sink (Section 2.0).
    Including frontier technologies such as biochar additions and the 
development of microbiome-assisted carbon accrual could further 
increase soil carbon sequestration potentials, perhaps by as much as 
1.8 fold.\24\ Worth noting too is the French Government's ``4 per 
mille'' initiative announced at the time of the 2016 Paris climate 
accord,\157\ which aims to increase global soil carbon stocks by 0.4% 
per year, an aspirational goal equivalent to sequestration rates of 3.4 
GtCeq yr-1 (272 GtC if sustained through 2100) 
that has attracted significant attention.158-160 Many, 
myself included, feel this rate is overambitious in part because we 
don't know the saturation potentials for most soils, but the initiative 
has raised awareness and will likely spur further research to identify 
additional soil carbon management interventions.
5.2  U.S. Potentials for Negative and Avoided Emissions by Land 
        Management Change
    Table 2 presents a summary synthesis of the management practices 
identified in the sections above for the U.S. Negative emissions, 
including Cropland management (Section 3.2.1), Cropland conversion to 
perennial grasses (3.2.2), Grazing land management (3.2.3), Wetland 
histosols restoration (3.2.4), and Forest management (3.2.6), sum to a 
potential total carbon storage rate of 414 MtCeq 
yr-1 (0.414 GtCeq yr-1).
    This rate is similar to those calculated for other recent U.S. 
summaries 28, 83, 159, 161 when considering individual 
practices. While other syntheses estimate a lower range of 75-174 
MtCeq yr-1, with an average rate of 85 
MtCeq yr-1, they do not include carbon 
sequestered due to improved forest management or the establishment of 
cellulosic bioenergy crops. These alone add 198 MtCeq 
yr-1. A 2007 Congressional Budget Office analysis \162\ that 
included forest management estimated a 2030 sequestration potential of 
479 MtCeq yr-1. Thus the present analysis 
(summing to 414 MtCeq yr-1 for negative 
emissions) is consistent with earlier analyses.
    As noted earlier, the duration of individual sequestration rates by 
different practices differ. Sequestration rates for all practices could 
be sustained for at least 30 years, and some for 50-80 years or more as 
noted in Section 5.1. With these durations, total negative emissions 
sum to 20.9 GtCeq through 2100 (Table 2).
    Avoided emissions are also additional in the present analysis. 
These include (a) improved fertilizer efficiency (Section 4.2.1), (b) 
rice water management for methane (4.2.2), and (c) cellulosic bioenergy 
production (Sections 4.2.3 and 4.2.4). These provide additional 
mitigation potentials that themselves sum to an annual capacity of 122 
MtCeq yr-1 (0.122 GtCeq 
yr-1), totaling 9.7 GtCeq through 2100 (Table 2). 
It is worth noting that the capacity of these activities is on-going 
and permanent, i.e. most of their carbon benefits are not subject to 
saturation as are biological carbon sinks, nor subject to re-emission 
upon management change or natural disturbance such as forest fires. It 
is also worth noting that, except for cellulosic biofuels, there is 
likely no overlap with decarbonization pathways for energy use. Should, 
however, energy analyses include cellulosic biofuel production at the 
magnitude noted here, then the avoided emissions here (72 MtC 
yr-1 or 5.7 GtC for 80 years) would be double counted so 
this total should be appropriately discounted. The negative emissions 
due to cellulosic biofuels--soil carbon capture--does not contribute to 
avoided fossil fuel use so should remain part of this total.

                                                     Table 2
----------------------------------------------------------------------------------------------------------------
                                    Local rate
         Practice change            (tCeq ha	1     Areal  extent   Annual total    Duration (yr)   Yr 2100 total
                                       yr	1)           (Mha)       (MtCeq yr	1)                       (GtCeq)
----------------------------------------------------------------------------------------------------------------
Negative emissions
  Cropland management (3.2.1)
    No till adoption                        0.40            a 94            37.6              30            1.13
    Reduced summer fallow                   0.09            a 20             1.8              30            0.05
    Winter cover crops                      0.52            a 66            34.3             80f            2.75
    Diversified crop rotations              0.05            a 46             2.3              80            0.18
    Manure & compost additions              0.71           a 8.5             6.0              80            0.48
  Cropland conversion to
   perennial grasses (3.2.2)
    Set-aside highly erodible               0.97            b 26            25.2              30            0.76
     cropland
    Cellulosic bioenergy on                 0.97            c 13            12.6              30            0.38
     grain ethanol lands
    Cellulosic bioenergy on                 0.48            d 55            26.4              30            0.79
     marginal lands
  Grazing land management
   (3.2.3)
    Improved stocking rates on              0.28           e 216            60.5              80            4.84
     rangeland
    Improved species composition            0.56            a 80            44.8              30            1.34
  Wetland histosol restoration              3.65           a 0.8             2.9              80            0.23
   (3.2.4)
  Forest management (3.2.6)
    Improved soil management--              0.32           e 256            81.9              50            4.10
     timberland
    Improved soil management--                                              22.5              50            1.13
     agroforestry
    Improved stand management                                               55.0              50            2.75
                                                                 ----------------                ---------------
      Subtotal--Negative                                                     414                            20.9
       emissions
                                                                 ----------------                ---------------
Avoided emissions
  Improved fertilizer efficiency
   (4.2.1)
    Avoided nitrous oxide                   0.36           c 125            45.0              80            3.60
     emissions
    Avoided CO2--fertilizer                                                  4.4              80            0.35
     production
  Rice water management for                 0.54           a 1.3             0.7              80            0.06
   methane (4.2.2)
  Cellulosic bioenergy
   production
    Production on grain ethanol             0.71            c 17            12.1              80            0.97
     lands (4.2.3)
    Production on marginal lands            1.08            d 55            59.4              80            4.75
     (4.2.4)
                                                                 ----------------                ---------------
      Subtotal--Avoided                                                      122                             9.7
       emissions
                                                                 ================                ===============
        Total potential                                                      535                            30.6
----------------------------------------------------------------------------------------------------------------
Potential sources and magnitude of U.S. greenhouse gas mitigation from changes in land management practices that
  lead to negative emissions (carbon storage) and avoided emissions for the period 2020-2100. Numbers in
  parentheses refer to sections in text for local sequestration values.
a Eagle, et al.48, 145.
b Sperow, et al.83.
c ERS \89\.
d Robertson, et al.\88\.
e Bigelow and Borchers \29\.
f Poeplau and Don \65\.
g USDA \163\.

    Assuming no overlap, and over an 80 year end-of-century lifetime, 
then, these avoided emissions practices sum to 9.7 GtCeq 
through 2100.
    Altogether, then, I conclude that U.S. potentials for mitigating 
greenhouse gas emissions through negative emissions due to land 
management practices on forest, range and crop lands in the 
conterminous U.S. sum to 20.9 GtCeq for the period 2020-
2100. This represents more than 20% of the global natural sequestration 
target needed to bring CO2 concentrations to 350 ppm.\4\ 
Including avoided emissions due to land management practices brings the 
sum to 30.6 GtCeq for the period 2020-2100, or >30% of the 
total needed.
    That the Federal Government manages 43% of rangeland and 44% of 
forests in the conterminous U.S. (see Section 3.2) allows an estimate 
of the sequestration potential on public grazing and forest lands of 
115 MtCeq yr-1, or 6.2 GtCeq through 
2100. About 56% of this total is sequestration on forest lands, the 
remainder on rangelands.
    In its annual inventory of greenhouse gas emissions and sinks for 
the U.S., the USEPA \11\ estimates for U.S. land management a 
background sink of 212 MtCeq yr-1 (0.212 
GtCeq yr-1) for 2015. The primary drivers of 
these sinks in 2015 were forest growth (181 MtCeq 
yr-1) and forestland expansion (21 MtCeq 
yr-1), with urban tree growth and landfills (9 
MtCeq yr-1) contributing most of the remaining 
sink. Decrementing this by concomitant changes in methane and nitrous 
oxide emissions brought the net land management sink to 207 
MtCeq yr-1. The 535 MtCeq 
yr-1 potential land management sink noted in Table 2 (both 
negative and avoided emissions) is additional to this existing 
background sink. Were the strategies in this report fully implemented, 
a future USEPA inventory might tally a net U.S. sink close to 750 
MtCeq yr-1 (0.750 GtCeq 
yr-1).
5.3 Barriers that Prevent Optimized Biotic Greenhouse Gas Mitigation in 
        the U.S.
    The principal barriers to adopting management practice changes to 
mitigate greenhouse gas emissions in the U.S. are neither knowledge-
based nor technical. There is ample evidence, detailed and summarized 
above, that land management changes can achieve real and verifiable 
negative and avoided emissions with high confidence. The values in 
Table 2 are, in general, conservative--they include values from field 
observations and experiments conducted throughout the U.S. and similar 
ecoregions, i.e., they are empirically-based, representative estimates 
from farm, rangeland, and forest systems typical of the U.S. Further 
research will lead to their refinement, but it seems unlikely that 
average values will change more than 20-30%, and, importantly, the 
values are in any case as likely to increase in magnitude as to 
decrease. Further, as noted earlier, not all possible practices to 
drive negative or avoided emissions are included.
    Research and experience show that farmers, ranchers, and forest 
managers who own and manage non-Federal lands are willing to accept 
payments for providing ecosystem services such as soil organic matter 
accrual, nitrate leaching avoidance, wetland protection, and greenhouse 
gas avoidance.164, 165 For example, in 2017, USDA and its 
partners worked with 680,000 land managers to fund the development of 
conservation plans for 27 million acres of working lands.\166\ Both 
research 164, 165, 167-169 and over-subscribed USDA 
conservation programs point to farmers' and other landowners' openness 
to accepting conservation and other ecosystem service payments through 
a variety of mechanisms, including auctions. Thus, the principal 
barrier for engaging landowners and managers is not feasibility or lack 
of interest, but lack of policy support and financial incentive.
    How much financial incentive is necessary? The success of USDA 
conservation programs show that farmers and ranchers are willing to 
accept relatively low payments for changing specific practices, 
sometimes as low as a few dollars per acre. In many cases the payments 
depend on cobenefits. Building soil carbon, for example, benefits soil 
fertility, water holding capacity, and drainage, and experimental 
auctions have shown lower payments would be required than, for example, 
reducing nitrous oxide emissions, which are considered by farmers to 
have fewer cobenefits.165, 170 Practices with higher 
management costs--cover crops, for example--would likewise require 
higher payments. That said, most analyses to date that include economic 
costs conclude that many practices could be implemented at costs as low 
as $10 per MtCO2 ($2.70 per MtC). Griscom, et al.,\9\ for 
example, state that \1/3\ of the potentials they consider could be 
provided at this cost, with the remainder requiring no more than $100 
per MtCO2, which is consistent with the expected avoided 
cost of holding warming to below 2 C by 2100.\171\ USEPA modeling 
\106\ concludes that some forest and agricultural management practices 
could be incentivized at carbon prices as low as $1 per 
MtCO2, with full implementation at $50.
    Various voluntary efforts such as the USDA Building Blocks for 
Climate Smart Agriculture and Forestry (https://www.usda.gov/oce/
climate--change/buildingblocks.html) \172\ provide frameworks for 
farmers, ranchers, and landowners to respond to climate change. For 
example, the Building Blocks program provides a series of measures 
intended to assist a wide variety of land management stakeholders to 
increase carbon storage and reduce greenhouse gas emissions; ten 
categories of activities range from soil health and nitrogen 
stewardship to grazing and pastureland management. The program provides 
case studies to inspire users and provides technical assistance through 
NRCS and other USDA professionals to help individual land managers meet 
personal greenhouse gas reduction goals. Only 3 years old, the 
effectiveness of the Building Blocks initiative is largely untested but 
it provides an evidence-based framework for engaging landowners and 
managers in the sorts of meaningful activities identified herein. The 
Building Blocks framework is an important start, but the quantitative 
goal it contains (33 MtCeq yr-1 by 2025) is far 
below the 535 MtCeq yr-1 identified in the 
present analysis, and because the initiative is strictly voluntary with 
no incentives, it is unlikely to meet even this goal.
    More useful is the on-line COMET-Farm tool (http://cometfarm.nrel.
colostate.edu) \133\ that allows farmers and ranchers to calculate the 
greenhouse gas impacts of current and projected land management 
practices. Calculations are based on the USDA's methods for quantifying 
farm-level emissions (https://www.usda.gov/oce/climate_change/
estimation.htm).\132\ Calculations are specific to individual fields as 
identified by aerial and satellite imagery, and cover most of the crop 
and grazing land practices in Sections 3.2 and 4.2, including avoided 
emissions from improved nitrogen fertilizer management, all of which 
make comparisons between business-as-usual and alternative practices 
straightforward and directly relevant to the land being managed.
    Likewise, national carbon registries offer a framework to provide 
landowners and carbon markets detailed evidence-based protocols for 
voluntarily quantifying the carbon captured or emissions avoided by 
specific land management practices. Both the American Carbon Registry 
(www.americancarbonregistry.org) and the Verified Carbon Standard 
(www.verra.org), for example, provide protocols for awarding carbon 
credits based on avoided nitrous oxide emissions by improved nitrogen 
fertilizer management 130, 131 as well as avoided methane 
emissions from improved rice management and wetland restoration.\173\
    That said, scaling up sequestration nationwide on the order 
discussed in the present report will require revisiting the many 
Federal policies and incentives that influence agricultural, grazing, 
and forestry practices on both private and public lands of the U.S. 
Without supportive Federal policies and payments sufficient to cover 
costs, farmers, ranchers, and forest owners are unlikely to participate 
in sufficient numbers to effect meaningful change.
6.0 Concluding Opinions
    Based upon a review of the literature, my own research, and in 
consultation with other experts in the field, it is my expert opinion 
that through improved land management practices, at a combined peak 
rate of 535 MtCeq yr-1 (0.535 GtCeq 
yr-1), about 31 GtCeq of additional emissions 
could be sequestered and avoided by land management changes on U.S. 
forestland, rangelands, and farms between 2020 and 2100. Some 21 GtC 
could be provided by negative emissions, i.e., natural carbon removal 
and storage by practices such as improved cropland and rangeland 
management. Another 10 GtC could be provided by avoided emissions from 
practices such as improved nitrogen management and cellulosic bioenergy 
production. We have known for decades the potential for most of these 
practices to contribute to negative or avoided emissions. Sequestration 
on this scale would meet the scientific prescription for sequestration 
set forth by Hansen, et al.4, 174, 175
            Signed this 13th day of April, 2018 in Cambridge, UK.
            
            
                                                   G. Philip Robertson.
Exhibit D: Government Climate and Energy Actions, Plans, and Policies 
        Must Be Based on a Maximum Target of 350 ppm Atmospheric 
        CO2 and 1 C by 2100 to Protect Young People and 
        Future Generations
Introduction
    Human laws can adapt to nature's laws, but the laws of nature will 
not bend for human laws. Government climate and energy policies must be 
based on the best available climate science to protect our climate 
system and vital natural resources on which human survival and welfare 
depend, and to ensure that young people's and future generations' 
fundamental and inalienable human rights are protected.
    Because carbon dioxide (CO2) is the primary driver of 
climate destabilization and ocean warming and acidification, all 
government policies regarding CO2 pollution and 
CO2 sequestration should be aimed at reducing global 
CO2 concentrations below 350 parts per million (ppm) by 
2100. Global atmospheric CO2 levels, as of 2019, are 
approximately 407 ppm and rising.\1\ An emission reductions and 
sequestration pathway back to 350 ppm could limit peak warming to 
approximately 1.3 C this century and stabilize long-term heating at 1 
C above pre-industrial temperatures.
---------------------------------------------------------------------------
    \1\ Ed Dlugokencky & Pieter Tans, NOAA/ESRL, www.esrl.noaa.gov/gmd/
ccgg/trends/.
---------------------------------------------------------------------------
    As explained in more detail below, there are numerous scientific 
bases and lines of evidence supporting setting 350 ppm and 1 C by 2100 
as the uppermost safe limit for atmospheric CO2 
concentrations and global warming. Beyond 2100, atmospheric 
CO2 may need to return to below 300 ppm to prevent the 
complete melting of Earth's ice sheets and protect coastal cities from 
sea level rise. Fortunately, it is still not only technically and 
economically feasible to return to those levels, but transitioning to 
renewable energy sources will provide significant economic and public 
health benefits and improve quality-of-life.
Why 350 ppm And 1 C Long-Term Warming?
    Three lines of robust and conclusive scientific evidence, based on 
the paleo-climate record and realworld observations show that above an 
atmospheric CO2 concentration of 350 ppm there is: (1) 
significant global energy imbalance; (2) massive ice sheet 
destabilization and sea level rise; and (3) ocean warming and 
acidification resulting in the bleaching death of coral reefs and other 
marine life.
(1) Energy Balance
    Earth's energy flow is out of balance. Because of a buildup of 
CO2 in our atmosphere, due to human activities, primarily 
the burning of fossil fuels and deforestation,\2\ more solar energy is 
retained in our atmosphere and less energy is released back into 
space.\3\ The energy imbalance of the Earth is roughly equivalent to 
2500 Camp Creek \4\ fires per day burning around the world.\5\ 
Returning CO2 concentrations to below 350 ppm would restore 
the energy balance of Earth by allowing as much heat to escape into 
space as Earth retains, an important historic balance that has kept our 
planet in the sweet spot for the past 10,000 years, supporting stable 
sea levels, enabling productive agriculture, and allowing humans and 
other species to thrive.\6\ The paleo-climate record shows that 
CO2 levels, temperature, and sea level all move together 
(see Figure 1). Humans have caused CO2 levels to shoot off 
the chart (circled in red), rising to levels unprecedented over the 
past 3 million years, and causing the energy imbalance.\7\
---------------------------------------------------------------------------
    \2\ Intergovernmental Panel on Climate Change, Summary for 
Policymakers, Climate Change 2014: Impacts, Adaptation, and 
Vulnerability 5 (2014).
    \3\ James Hansen, et al., Assessing ``Dangerous Climate Change'': 
Required Reduction of Carbon Emissions to Protect Young People, Future 
Generations and Nature, PLOS ONE 8:12 (2013) [hereinafter Assessing 
``Dangerous Climate Change''].
    \4\ The Camp Creek fire was the 2018 California fire, the deadliest 
and most destructive in the state's history, that burned over 150,000 
acres (almost 240 square miles).
    \5\ Steven W. Running, Declaration in Support of Plaintiffs, 
Juliana v. United States (https://www.ourchildrenstrust.org/s/DktEntry-
21-12-Running-Dec-ISO-Urgent-Motion-for-Preliminary-Injunction.pdf), 
No. 18-36082, Doc. 21-12 (9th Cir. Feb. 7, 2019).
    \6\ James Hansen, Storms of My Grandchildren 166 (2009).
    \7\ Willeit, et al., Mid-Pleistocene transition in glacial cycles 
explained by declining CO2 and regolith removal. Science 
Advances (2019).
---------------------------------------------------------------------------
Figure 1


          Evidence from the paleo-climate record showing the 
        relationship between CO2 concentration, global 
        temperature, and sea level.
(2) Ice Sheets and Sea Level Rise
    The last time the ice sheets appeared stable in the modern era was 
in the 1980s when the atmospheric CO2 concentration was 
below 350 ppm. The consequences of >350 ppm and 1 C of warming are 
already visible, significant, and dangerous for humanity. With just 1 
C of warming, glaciers in all regions of the world are shrinking, and 
the rate at which they are melting is accelerating.\8\ Large parts of 
the Greenland and Antarctic ice sheets, which required millennia to 
grow, are teetering on the edge of irreversible disintegration, a point 
that if reached, would lock-in major ice sheet mass loss, sea level 
rise of many meters, and worldwide loss of coastal cities--a 
consequence that would be irreversible on any timescale relevant to 
humanity (see Figure 2).\9\ Greenland's ice sheet melt is currently 
occurring faster than anytime during the last 3\1/2\ centuries, with a 
33% increase alone since the 20th century.\10\ The paleo-climate record 
shows the last time atmospheric CO2 levels were over 400 
ppm, the seas were 70 higher than they are today and that heating 
consistent with CO2 concentrations as low as 450 ppm may 
have been enough to melt almost all of Antarctica.\11\ While many 
experts are predicting multi-meter sea level rise this century, even 
NOAA's modest estimate of 3-6 by 2100 would impact between 4 and 13 
million Americans (see Figure 3).\12\
---------------------------------------------------------------------------
    \8\ Zemp, et al., Global glacier mass changes and their 
contributions to sea-level rise from 1961-2016. Nature (2019); B. 
Menounos, Heterogeneous Changes in Western North American Glaciers 
Linked to Decadal Variability in Zonal Wind Strength, Geophysical 
Research Letters (2018).
    \9\ Hansen, Assessing ``Dangerous Climate Change,'' at 13; see also 
James Hansen, et al., Ice Melt, Sea Level Rise and Superstorms; 
Evidence from Paleoclimate Data, Climate Modeling, and Modern 
Observations that 2 C Global Warming Could be Dangerous, Atmos. Chem. 
& Phys. 16, 3761 (2016) [hereinafter Ice Melt, Sea Level Rise and 
Superstorms].
    \10\ Trusel, L.D., et al., Nonlinear rise in Greenland runoff in 
response to post-industrial Arctic warming, Nature (2018).
    \11\ Dec. of Dr. James E. Hansen, Juliana,, et al., v. United 
States, et al., No. 6:15-cv-01517-TC, 14 (D. Or. Aug. 12, 2015); 
Intergovernmental Panel on Climate Change: 2007 Working Group I: The 
Physical Science Basis, Chapter 6.3.2, What Does the Record of the Mid-
Pliocene Show?; Dowsett & Cronin, High eustatic sea level during the 
middle Pliocene: Evidence from the southeastern U.S. Atlantic Coastal 
Plain, Geology (1990); Shackleton, et al., Pliocene stable isotope 
stratigraphy of ODP Site 846, Proceedings of the Ocean Drilling 
Program, Scientific Results (1995).
    \12\ NOAA, Examining Sea Level Rise Exposure for Future 
Populations, https://coast.noaa.gov/digitalcoast/stories/population-
risk.
---------------------------------------------------------------------------
Figure 2


          Antarctic melt water from the Nansen ice shelf.

    Most climate models represent sea level rise as a gradual linear 
response to melting ice sheets, but the historic climate record shows 
something very different. In reality, seas do not rise slowly and 
predictably but rather in quick pulses as ice sheets destabilize.\13\ 
Scientists believe we have a chance to preserve the large ice sheets of 
Greenland and Antarctica and most of our shorelines and ecosystems if 
we limit long-term warming by the end of the century to no more than 1 
C above pre-industrial levels (short-term warming will inevitably 
exceed 1 C but must not exceed 1 C for more than a short amount of 
time).
---------------------------------------------------------------------------
    \13\ Wanless, H.R., et al., Dynamics and Historical Evolution of 
the Mangrove/Marsh Fringe Belt of Southwest Florida, in Response to 
Sea-level History, Biogenic Processes, Storm Influences and Climatic 
Fluctuations. Semi-annual Research Report (June 1993 to February 1994); 
Hansen, Ice Melt, Sea Level Rise and Superstorms, at 3761; Hansen, 
Assessing ``Dangerous Climate Change,'' at 20.
---------------------------------------------------------------------------
Figure 3


          South Florida, including Miami, will face significant 
        inundation with 6 of sea level rise.
(3) Ocean Warming and Acidification
    Our oceans have absorbed 93% of the excess heat in the atmosphere 
trapped by greenhouse gases (see Figure 4) as well as approximately 30% 
of CO2 emitted into the atmosphere, causing ocean 
temperatures to surge and the ocean to become more acidic.\14\ Indeed, 
our oceans are warming much more rapidly than previously-thought.\15\ 
Many marine ecosystems, and particularly coral reef ecosystems, cannot 
tolerate the increased warning and acidity of ocean waters that result 
from increased CO2 levels.\16\ At today's CO2 
concentration, around 407 ppm,\17\ critically important ocean 
ecosystems, such as coral reefs, are rapidly declining and will be 
irreversibly damaged from high ocean temperatures and repeated mass 
bleaching events if we do not quickly curtail emissions (see Figures 5 
and 6).\18\ According to the Intergovernmental Panel on Climate Change, 
bleaching events are occurring more frequently than the IPCC previously 
projected and 70-90% of the world's coral reefs could disappear as soon 
as 2030 (the IPCC also predicts 99% of coral reefs will die with 2 C 
warming).\19\ Even the recent National Climate Assessment acknowledged 
that coral reefs in Florida, Hawaii, Puerto Rico, and the U.S. Virgin 
Islands have been harmed by mass bleaching and coral diseases and could 
disappear by mid-century as a result of warming waters.\20\ Scientists 
believe we can protect marine life and prevent massive bleaching and 
die-off of coral reefs only by rapidly returning CO2 levels 
to below 350 ppm.\21\
---------------------------------------------------------------------------
    \14\ Hansen, Assessing ``Dangerous Climate Change,'' at 1; Climate 
Change 2013: The Physical Science Basis. Contribution of Working Group 
I to the Fifth Assessment Report of the Intergovernmental Panel on 
Climate Change (Cambridge University Press, 2013); Cheng, et al., How 
fast are the oceans warming? 363 Science 128 (2019); National Oceanic 
and Atmospheric Administration, What is Ocean Acidification?, https://
oceanservice.noaa.gov/facts/acidification.html.
    \15\ Cheng, L., et al., How fast are the oceans warming?, 363 
Science 128 (2019).
    \16\ Hughes, et al., Global warming impairs stock-recruitment 
dynamics of corals, Nature (2019).
    \17\ Ed Dlugokencky and Pieter Tans, NOAA/ESRL, www.esrl.noaa.gov/
gmd/ccgg/trends/.
    \18\ Frieler, K., et al., Limiting global warming to 2 degrees C is 
unlikely to save most coral reefs. Nature Climate Change 3: 165-170. 
(2013); Veron, J.,, et al; The coral reef crisis: The critical 
importance of <350ppm CO2. Marine Pollution Bulletin 58: 
1428-1436 (2009); Hughes, T., et al., Spatial and temporal patterns of 
mass bleaching of corals in the Anthropocene, Science 359: 80-83 
(2018); Hughes, T., et al. Global warming impairs stock-recruitment 
dynamics of corals, Nature (2019).
    \19\ Hoegh-Guldberg, Ove, et al., Impacts of 1.5 C Global Warming 
on Natural and Human Systems. In Global Warming of 1.5 C. An IPCC 
Special Report on the impacts of global warming of 1.5 C above pre-
industrial levels and related global greenhouse gas emission pathways, 
in the context of strengthening the global response to the threat of 
climate change, sustainable development, and efforts to eradicate 
poverty at pp. 225-226 (2018); IPCC, Summary for Policymakers of IPCC 
Special Report on Global Warming of 1.5 C Approved by Governments 
(2018).
    \20\ Pershing, A.J., et al., Oceans and Marine Resources. In 
Impacts, Risks, and Adaptation in the United States: Fourth National 
Climate Assessment, Volume II, USGCRP (2018)[.]
    \21\ Veron, J., et al., The coral reef crisis: The critical 
importance of <350 ppm CO2, 58 Marine Pollution Bulletin 
1428 (2009).
---------------------------------------------------------------------------
Figure 4


          Over 90% of the excess energy from human caused climate 
        change has been absorbed by the oceans, adding energy to storms 
        and harming coral reefs around the globe.

    No scientific institution, including the IPCC, has ever concluded 
that 2 C warming or 450 ppm would be safe for ocean life. According to 
Dr. Ove Hoegh-Guldberg, one of the world's leading experts on ocean 
warming and acidification, and a Coordinating Lead Author on the 
``Oceans'' chapter of the IPCC's Fifth Assessment Report and on the 
``Impacts of 1.5 C global warming on natural and human systems'' of 
the IPCC's Special Report on 1.5 C:

          ``Allowing a temperature rise of up to 2 C would seriously 
        jeopardize ocean life, and the income and livelihoods of those 
        who depend on healthy marine ecosystems. Indeed, the best 
        science available suggests that coral dominated reefs will 
        completely disappear if carbon dioxide concentrations exceed 
        much more than today's concentrations. Failing to restrict 
        further increases in atmospheric carbon dioxide will eliminate 
        coral reefs as we know them and will deny future generations of 
        children from enjoying these wonderful ecosystems.'' \22\
---------------------------------------------------------------------------
    \22\ Id.
---------------------------------------------------------------------------
Figure 5


          Healthy coral like this are already gravely threatened and 
        will likely die with warming of 1.5 C.
Figure 6


          Bleached coral from warmer ocean temperatures.
Additional Observations Illustrate the Dangers of Increased Warming
    In addition to the evidence discussed above which illustrates the 
necessity of ensuring that the atmospheric CO2 concentration 
returns to no more than 350 ppm, based on present day observations 
about climate impacts occurring now, it is clear that the present level 
of 1 C is already causing significant climate impacts and additional 
warming will exacerbate these already dangerous impacts. Climate 
impacts that are already being experienced today include:

   Declining snowpack and rising temperatures are increasing 
        the length and severity of drought conditions, especially in 
        the western United States and Southwest, causing problems for 
        agriculture users, forcing some people to relocate, and leading 
        to water restrictions.\23\
---------------------------------------------------------------------------
    \23\ Steven W. Running, Declaration in Support of Plaintiffs, 
Juliana v. United States (https://www.ourchildrenstrust.org/s/DktEntry-
21-12-Running-Dec-ISO-Urgent-Motion-for-Preliminary-Injunction.pdf), 
No. 18-36082, Doc. 21-12 (9th Cir. Feb. 7, 2019).

   In the western United States, the wildfire season is now 
        almost 3 months longer (87 days) than it was in the 1980s.\24\
---------------------------------------------------------------------------
    \24\ Steven W. Running, Declaration in Support of Plaintiffs, 
Juliana v. United States (https://www.ourchildrenstrust.org/s/DktEntry-
21-12-Running-Dec-ISO-Urgent-Motion-for-Preliminary-Injunction.pdf), 
No. 18-36082, Doc. 21-12 (9th Cir. Feb. 7, 2019).

   Extreme weather events, such as intense rainfall events that 
        cause flooding, are increasing in frequency and severity 
        because a warmer atmosphere holds more moisture.\25\ What are 
        supposedly 1-in-1,000-year rainfall events are now occurring 
        with alarming frequency--in 2018 there were at least five such 
        events.\26\
---------------------------------------------------------------------------
    \25\ Kevin E. Trenberth, Declaration in Support of Plaintiffs, 
Juliana v. United States (https://www.ourchildrenstrust.org/s/DktEntry-
21-3-Trenberth-Dec-ISO-Urgent-Motion-for-Preliminary-Injunction.pdf), 
No. 18-36082, Doc. 21-3 (9th Cir. Feb. 7, 2019).
    \26\ Belles, F., America's `One-in-1,000-Year' Rainfall Events in 
2018, The Weather Channel (Sept. 27, 2018).

   Tropical storms and hurricanes are increasing in intensity, 
        both in terms of rainfall and windspeed, as warmer oceans 
        provide more energy for the storms (we saw this with Hurricanes 
        Harvey, Irma, and Maria in 2017) (Figure 7).\27\
---------------------------------------------------------------------------
    \27\ Kevin E. Trenberth, Declaration in Support of Plaintiffs, 
Juliana v. United States (https://www.ourchildrenstrust.org/s/DktEntry-
21-3-Trenberth-Dec-ISO-Urgent-Motion-for-Preliminary-Injunction.pdf), 
No. 18-36082, Doc. 21-3 (9th Cir. Feb. 7, 2019).
---------------------------------------------------------------------------
Figure 7


          Flooding in Port Arthur, Texas on August 13, 2018 after 
        Hurricane Harvey.

   Terrestrial ecosystems are experiencing compositional and 
        structural changes, with major adverse consequences for 
        ecosystem services.\28\
---------------------------------------------------------------------------
    \28\ Nolan, et al., Past and future global transformation of 
terrestrial ecosystems under climate change, Science (2018).

   Terrestrial, freshwater, and marine species are experiencing 
        a significant decrease in population size and geographic range, 
        with some going extinct and others are facing the very real 
        prospect of extinction--the rapid rate of extinctions has been 
        called the 6th mass extinction.\29\
---------------------------------------------------------------------------
    \29\ G. Ceballos, et al., Accelerated modern human-induced species 
losses: Entering the sixth mass extinction, Science Advances (2015); 
Steven W. Running, Expert Report, Juliana v. United States (https://
www.ourchildrenstrust.org/s/Doc-264-1-Running-Expert-Report.pdf), No. 
6:15-cv-01517-TC, Doc. 264-1 (D. Or. June 28, 2018).

   Human health and well-being are already being affected by 
        heat waves, floods, droughts, and extreme events; infectious 
        diseases; quality of air, food, and water.\30\ Doctors and 
        leading medical institutions are calling climate change a 
        ``health emergency.'' \31\ Children are being uniquely impacted 
        by climate change.\32\
---------------------------------------------------------------------------
    \30\ Ebi, K. L., et al., Human Health. In Impacts, Risks, and 
Adaptation in the United States: Fourth National Climate Assessment, 
Volume II, USGCRP (2018).
    \31\ Solomon, C.G. & LaRocque R.C., Climate Change--A Health 
Emergency, N. Engl. J. Med. 380:3 (2019).
    \32\ May, C., et al., Northwest. In Impacts, Risks, and Adaptation 
in the United States: Fourth National Climate Assessment, Volume II, 
USGCRP (2018); Watts, N., et al., The 2018 report of the Lancet 
Countdown on health and climate change: shaping the health of nations 
for centuries to come, Lancet, Vol. 392 at 2482 (2018); Brief of Amici 
Curiae Public Health Experts, Public Health Organizations, and Doctors 
in Support of Plaintiffs (https://www.ourchildrenstrust.org/s/DktEntry-
47-Amicus-of-Public-Health-Experts-ISO-Pls.pdf), No. 18-36082, Doc. 47 
(9th Cir. Mar. 1, 2019).

   In addition to physical harm, climate change is causing 
        mental health impacts, ranging from stress to suicide, due to 
        exposure to climate impacts, displacement, loss of income, 
        chronic stress, and other impacts of climate change.\33\
---------------------------------------------------------------------------
    \33\ Lise Van Susteren, Expert Report, Juliana v. United States 
(https://www.ourchildrenstrust.org/s/Doc-271-1-Van-Susteren-Expert-
Report.pdf), No. 6:15-cv-01517-TC, Doc. 271-1 (D. Or. June 28, 2018).

   As Congress has recognized, ``climate change is a direct 
        threat to the national security of the United States and is 
        impacting stability in areas of the world both where the United 
        States Armed Forces are operating today, and where strategic 
        implications for future conflict exist.'' \34\ Senior military 
        leaders have called climate change ``the most serious national 
        security threat facing our Nation today,'' \35\ a conclusion 
        similarly recognized by our nation's intelligence 
        community.\36\ Climate change is increasing food and water 
        shortages, pandemic disease, conflicts over refugees and 
        resources, and destruction to homes, land, infrastructure, and 
        military assets, directly threatening our military personnel 
        and the ``Department of Defense's ability to defend the 
        Nation'' (see Figure 8).\37\
---------------------------------------------------------------------------
    \34\ National Defense Authorization Act for Fiscal Year 2018, Pub. 
L. No. 115-91, 131 Stat. 1358.
    \35\ Vice Admiral Lee Gunn, USN (Ret.), Declaration in Support of 
Plaintiffs, Juliana v. United States (https://
www.ourchildrenstrust.org/s/DktEntry-21-17-Gunn-Dec-ISO-Urgent-Motion-
for-Preliminary-Injunction.pdf), No. 18-36082, Doc. 21-17 (9th Cir. 
Feb. 7, 2019) (emphasis in original); see also CNA Military Advisory 
Board, National Security and the Accelerating Risks of Climate Change 
(2014), https://www.cna.org/cna_files/pdf/MAB_5-8-14.pdf.
    \36\ National Intelligence Council, Implications for U.S. National 
Security of Anticipated Climate Change (Sept. 2016), https://
www.dni.gov/files/documents/Newsroom/Reports and Pubs/
Implications_for_US_National_Security_of_Anticipated_Climate_Change.pdf.

    \37\ U.S. Dep't of Defense, 2014 Climate Change Adaptation Roadmap 
(2014), https://www.acq.osd.mil/eie/downloads/CCARprint_wForward_e.pdf.
---------------------------------------------------------------------------
Figure 8


          Offutt Air Force Base was impacted by flood waters during 
        flooding in Nebraska during spring 2019.

   Climate change is already causing vast economic harm in the 
        United States. Since 1980 the United States has experienced 246 
        climate and weather disasters that each caused damages in 
        excess of $1 billion, for a total cost of $1.6 trillion.\38\ In 
        2018 alone, Congress appropriated more than $130 billion for 
        weather and climate related disasters.\39\
---------------------------------------------------------------------------
    \38\ NOAA, Billion Dollar U.S. Weather/Climate Disasters 1980-2019 
(2019), http://www.ncdc.noaa.gov/billions/events.pdf.
    \39\ U.S. House of Representatives Committee on the Budget, The 
Budgetary Impact of Climate Change 2 (Nov. 27, 2018).

    These already serious impacts will grow in severity and will impact 
increasingly large numbers of people and parts of the world if 
CO2 concentrations continue to rise. If we want our children 
and grandchildren to have a safe planet to live on, full of health and 
biodiversity rather than chaos and conflict, we must follow the best 
scientific prescription to restore Earth's energy balance and avoid the 
destruction of our planet's atmosphere, climate, and oceans.
International Political Targets of 1.5 C Or 2 C Are Not Science-Based 
        and Are Not Safe
    International, politically-recognized targets like 1.5 C or ``well 
below'' 2 C--which are commonlyassociated with long-term atmospheric 
CO2 concentrations of 425 and 450 ppm, respectively--have 
not been and are not presently considered safe or scientifically-sound 
targets for present or future generations.
    Importantly, the Intergovernmental Panel on Climate Change 
(``IPCC'') has never established nor endorsed a target of 1.5 C or 2 
C warming as a limit below which the climate system will be 
stable.\40\ It is beyond the IPCC's declared mandate to endorse a 
particular threshold of warming as ``safe'' or ``dangerous.'' As the 
IPCC makes clear, ``each major IPCC assessment has examined the impacts 
of [a] multiplicity of temperature changes but has left [it to the] 
political processes to make decisions on which thresholds may be 
appropriate.'' \41\
---------------------------------------------------------------------------
    \40\ Dec. of Dr. James E. Hansen, Juliana, et al., v. United 
States, et al., No. 6:15-cv-01517-TC, 5 (D. Or. Aug. 12, 2015).
    \41\ IPCC, Climate Change 2014: Mitigation of Climate Change, 
Contribution of Working Group III to the Fifth Assessment Report, 125 
(2014), http://report.mitigation2014.org/report/
ipcc_wg3_ar5_chapter1.pdf.
---------------------------------------------------------------------------
    Neither 1.5 C nor 2 C warming above pre-industrial levels has 
ever been considered ``safe'' from either a political or scientific 
point of view. The 
2 C figure was originally adopted in the political arena ``from a set 
of heuristics,'' and it has retained predominantly political character 
ever since.\42\ It has recently been all-but-abandoned as a credible 
policy goal, in light of the findings in IPCC's 1.5 C Special Report, 
and the mounting evidence leading up to its publication, that 2 C 
would be catastrophic relative to lower, still-achievable levels of 
warming.\43\
---------------------------------------------------------------------------
    \42\ Randalls, S. History of the 2 C Temperature Target. 1. WIREs 
Climate Change 598, 603 (2010); Jaeger, C. and J. Jaeger, Three views 
of two degrees. 11 (Suppl. 1) Regional Environmental Change S15 (2011).
    \43\ IPCC, Summary for policymakers at 13-14, Climate Change 2014: 
Impacts, Adaptation, and Vulnerability (2014), http://www.ipcc.ch/pdf/
assessment-report/ar5/wg2/ar5_wgII_spm_en.
pdf; UNFCCC, Report on the structured expert dialogue on the 2013-2015 
review, 18 (2015), http://unfccc.int/resource/docs/2015/sb/eng/
inf01.pdf; Petra Tschakert, 1.5 C or 2 C: a conduit's view from the 
science-policy interface at COP20 in Lima, Peru, Climate Change 
Responses 8 (2015), http://www.climatechangeresponses.com/content/2/1/
3; IPCC, Global warming of 1.5 C: An IPCC Special Report on the 
impacts of global warming of 1.5 C above pre-industrial levels and 
related global greenhouse gas emission pathways, in the context of 
strengthening the global response to the threat of climate change, 
sustainable development, and efforts to eradicate poverty (2018), 
https://www.ipcc.ch/sr15/.
---------------------------------------------------------------------------
    On the other hand, the idea of a 1.5 C target was first raised by 
the Association of Small Island States (AOSIS) in the negotiations 
leading up to the ill-fated 2009 UNFCCC Conference of Parties in 
Copenhagen.\44\ AOSIS, however, was explicitly advocating a well below 
1.5 C and well below 1 C target, on the basis of the research of Dr. 
James Hansen and his colleagues.\45\ Political compromise on this 
science-based target then led to the adoption of a goal of ``pursuing 
efforts to limit the temperature increase to 1.5 C above pre-
industrial levels'' in Article 2 of the Paris Agreement. Yet the 2018 
IPCC Special Report on 1.5 C has made clear that allowing a 
temperature rise of 1.5 C:
---------------------------------------------------------------------------
    \44\ See Webster, R. A brief history of the 1.5C target. Climate 
Change News (December 10, 2015), http://www.climatechangenews.com/2015/
12/10/a-brief-history-of-the-1-5c-target/; Submission from Grenada on 
behalf of AOISIS to the Ad Hoc Working Group on Further Commitments for 
Annex I Parties Under the Kyoto Protocol, U.N. Doc. FCCC/KP/AWG/2009/
MISC.1/Add.1 (25 March 2009), https://unfccc.int/sites/default/files/
resource/docs/2009/awg7/eng/misc01a01.pdf.
    \45\ Submission from Grenada on behalf of AOISIS to the Ad Hoc 
Working Group on Further Commitments for Annex I Parties Under the 
Kyoto Protocol, U.N. Doc. FCCC/KP/AWG/2009/MISC.1/Add.1 (25 March 
2009), https://unfccc.int/sites/default/files/resource/docs/2009/awg7/
eng/misc01a01.pdf, citing Hansen, J., et al., Target Atmospheric 
CO2: Where Should Humanity Aim? 2 The Open Atmospheric 
Science Journal 217 (2008).

          is not considered `safe' for most nations, communities, 
        ecosystems, and sectors and poses significant risks to natural 
        and human systems as compared to current warming of 1 C (high 
        confidence) . . . .\46\
---------------------------------------------------------------------------
    \46\ Roy, J., et al., Sustainable Development, Poverty Eradication 
and Reducing Inequalities. In Global Warming of 1.5C. An IPCC Special 
Report on the impacts of global warming of 1.5C above pre-industrial 
levels and related global greenhouse gas emission pathways, in the 
context of strengthening the global response to the threat of climate 
change, sustainable development, and efforts to eradicate poverty at 
447 (2018) (emphasis added)

    Dr. James Hansen warns that ``distinctions between pathways aimed 
at 1 C and 2 C warming are much greater and more fundamental than the 
numbers 1 C and 2 C themselves might suggest. These fundamental 
distinctions make scenarios with 2 C or more global warming far more 
dangerous; so dangerous, we [James Hansen, et al.] suggest, that aiming 
for the 2 C pathway would be foolhardy.'' \47\ This target is at best 
the equivalent of ``flip[ping] a coin in the hopes that future 
generations are not left with few choices beyond mere survival. This is 
not risk management, it is recklessness and we must do better.'' \48\
---------------------------------------------------------------------------
    \47\ Id. at 15.
    \48\ Matt Vespa, Why 350? Climate Policy Must Aim to Stabilize 
Greenhouse Gases at the Level Necessary to Minimize the Risk of 
Catastrophic Outcomes, 36 Ecology Law Currents 185, 186 (2009), http://
www.biologicaldiversity.org/publications/papers/Why_350.pdf.
---------------------------------------------------------------------------
    Tellingly, more than 45 eminent scientists from over 40 different 
institutions have published in peer-reviewed journals finding that the 
maximum level of atmospheric CO2 consistent with protecting 
humanity and other species is 350 ppm, and no one, including the IPCC, 
has published any scientific evidence to counter that 350 is the 
maximum safe concentration of CO2.\49\
---------------------------------------------------------------------------
    \49\ James Hansen, et al., Target Atmospheric CO2: Where 
Should Humanity Aim? (2008); James Hansen, et al., Assessing 
``Dangerous Climate Change'': Required Reduction of Carbon Emissions to 
Protect Young People, Future Generations and Nature (2013); James 
Hansen, et al., Ice Melt, Sea Level Rise and Superstorms: Evidence From 
Paleoclimate Data, Climate Modeling, and Modern Observations That 2 C 
Global Warming Could Be Dangerous (2016); James Hansen, et al., Young 
People's Burden: Requirement of Negative CO2 Emissions 
(2017); Veron, J., et al., The Coral Reef Crisis: The Critical 
Importance of <350 ppm CO2 (2009); Frieler, K., et al., 
Limiting global warming to 2 C is unlikely to save most coral reefs 
(2012).
---------------------------------------------------------------------------
A 1.5 Or 2 C Target Risks Locking-In Dangerous Feedbacks
    The longer the length of time atmospheric CO2 
concentrations remain at dangerous levels (i.e., above 350 ppm) and 
there is an energy imbalance in the atmosphere, the risk of triggering, 
and locking-in, dangerous warming-driven feedback loops increases. The 
1.5 C or 2 C target reduces the likelihood that the biosphere will be 
able to sequester CO2 due to carbon cycle feedbacks and 
shifting climate zones.\50\ As temperatures warm, forests burn and 
soils warm, releasing their carbon. These natural carbon ``sinks'' 
become carbon ``sources'' and a portion of the natural carbon 
sequestration necessary to drawdown excess CO2 simply 
disappear. Another dangerous feedback includes the release of methane, 
a potent greenhouse gas, as the global tundra thaws.\51\ These 
feedbacks might show little change in the short-term, but can hit a 
point of no return, even at a 1.5 C or 2 C temperature increase, 
which will trigger accelerated heating and sudden and irreversible 
catastrophic impacts. Moreover, an emission reduction target aimed at 2 
C would ``yield a larger eventual warming because of slow feedbacks, 
probably at least 3 C.'' \52\ Once a temperature increase of 2 C is 
reached, there will already be ``additional climate change `in the 
pipeline' even without further change of atmospheric composition.'' 
\53\
---------------------------------------------------------------------------
    \50\ Id. at 15, 20.
    \51\ Id.
    \52\ Hansen, Assessing ``Dangerous Climate Change,'' at 15.
    \53\ Id. at 19.
---------------------------------------------------------------------------
It Is Technologically and Economically Feasible To Reduce 
        CO2 Levels to 350 ppm by 2100
    There are two steps to reducing CO2 levels to 350 ppm by 
the end of the century: (1) reducing CO2 emissions; and (2) 
sequestering excess CO2 already in the atmosphere. Carbon 
dioxide emission reductions of approximately 80% by 2030 and close to 
100% by 2050 (in addition to the requisite CO2 
sequestration) are necessary to keep long-term warming to 1 C and the 
atmospheric CO2 concentration to 350 ppm. Emission reduction 
targets that seek to reduce CO2 emissions by 80% by 2050 are 
consistent with long-term warming of 2 C and an atmospheric 
CO2 concentration of 450 ppm, which, as described above, 
would result in catastrophic and irreversible impacts for the climate 
system and oceans. Importantly, it is economically and technologically 
feasible to transition the entire U.S. energy system to a zero-
CO2 energy system by 2050 and to drawdown the excess 
CO2 in the atmosphere through reforestation and carbon 
sequestration in soils.\54\
---------------------------------------------------------------------------
    \54\ See Mark Z. Jacobson, et al., 100% Clean and Renewable Wind, 
Water, and Sunlight (WWS) All-Sector Energy Roadmaps for the 50 United 
States, 8 Energy & Envtl. Sci. 2093 (2015) (for plans on how the United 
States and over 100 other countries can transition to a 100% renewable 
energy economy see www.thesolutionsproject.org); see also Arjun 
Makhijani, Carbon-Free, Nuclear-Free: A Roadmap for U.S. Energy Policy 
(2007); B. Haley, et al., 350 ppm pathways for the United States 
(2019).
---------------------------------------------------------------------------
    Deep Decarbonization Pathways Project and Evolved Energy Research 
recently completed research and very sophisticated modeling describing 
a nearly complete phase out of fossil fuels in the U.S. by 2050.\55\ 
They describe six different technologically feasible pathways to 
drastically, and quickly, cut our reliance on fossil fuels and achieve 
the requisite level of emissions reductions in the U.S. while meeting 
our nation's forecasted energy needs. All of the 350 ppm pathways rely 
on four pillars of action: (a) investment in energy efficiency; (b) 
electrification of everything that can be electrified; (c) shifting to 
very low-carbon and primarily renewable electricity generation; and (d) 
carbon dioxide capture as fossil fuels are phased out. The six 
scenarios are used to evaluate the ability to meet the targets even 
absent one key technology. For example, one scenario describes a route 
to 350 absent construction of new nuclear facilities; another 
illustrates getting to 350 with extremely limited biomass technology; 
still another describes a way to 350 without any carbon capture and 
storage. Even absent a key technology, each of these six routes are 
viable and cost effective.
---------------------------------------------------------------------------
    \55\ B. Haley, et al., 350 ppm pathways for the United States 
(2019).
---------------------------------------------------------------------------
    The study also concludes that the cost of the energy system 
transition is affordable. The total cost of supplying and using energy 
in the U.S. in 2016 was about 5.6% of GDP (see Figure 9).\56\ A 
transition from fossil fuels to low carbon energy sources is expected 
to increase those costs by no more than an additional two to three 
percent of GDP. Even with this small and temporary added expense, the 
cost would still be well below the 9.5% of GDP spent on the energy 
system in 2009 (not to mention well below the harm to the economy 
caused by climate change). Once the transition is complete, the cost of 
energy will remain low and stable because we will no longer be 
dependent on volatile global fossil fuel markets for our energy 
supplies. As Nobel Laureate Economist Dr. Joseph Stiglitz has stated: 
``[t]he benefits of making choices today that limit the economic costs 
of climate change far outweigh any economic costs associated with 
limiting our use of fossil fuels.'' \57\
---------------------------------------------------------------------------
    \56\ B. Haley, et al., 350 ppm pathways for the United States 
(2019).
    \57\ Joseph E. Stiglitz, Ph.D., Declaration in Support of 
Plaintiffs, Juliana v. United States (https://
www.ourchildrenstrust.org/s/DktEntry-21-14-Stiglitz-Dec-ISO-Urgent-
Motion-for-Preliminary-Injunction.pdf), No. 18-36082, Doc. 21-14 (9th 
Cir. Feb. 7, 2019).
---------------------------------------------------------------------------
Figure 9


          Historic and Projected Costs of Energy in the U.S.

    Other experts have already prepared plans for all 50 U.S. states as 
well as for over 139 countries that demonstrate the technological and 
economic feasibility of transitioning off of fossil fuels toward 100% 
of energy, for all energy sectors, from clean and renewable energy 
sources: wind, water, and sunlight by 2050 (with 80% reductions in 
fossil fuels by 2030).\58\
---------------------------------------------------------------------------
    \58\ Mark Z. Jacobson, et al., 100% Clean and Renewable Wind, 
Water, and Sunlight (WWS) All-Sector Energy Roadmaps for the 50 United 
States, 8 Energy & Envtl. Sci. 2093 (2015). For a graphic depicting the 
overview of the plan for the United States see: https://
thesolutionsproject.org/why-clean-energy/#/map/countries/location/USA.
---------------------------------------------------------------------------
    Products already exist that enable new construction or retrofits 
that result in zero greenhouse gas buildings. We have the technology to 
meet all electricity needs with zero-emission electric generation. We 
know how to achieve zero-emission transportation, including aviation. 
These actions result in other benefits, such as improved health, job 
creation, and savings on energy costs.
    The amount of natural carbon sequestration required is also proven 
to be feasible. Researchers have evaluated the potential to drawdown 
excess carbon dioxide in the atmosphere by increasing the carbon stored 
in forests, soils, and wetlands, and have found significant potential 
for these natural systems to support a return to 350 ppm by the end of 
the century.\59\ We know the agricultural, rangeland, wetland, and 
forest management practices that decrease greenhouse gas emissions and 
increase sequestration.
---------------------------------------------------------------------------
    \59\ Benson W. Griscom, et al., Natural Climate Solutions, 
Proceedings of the National Academies of Sciences (2017); Joseph E. 
Fargione, et al., Natural Climate Solutions for the United States, 
Science Advances (2018).
---------------------------------------------------------------------------
    There is no scientific, technological, or economic reason to not 
adopt a 350 ppm and 1 C by 2100 target. There are abundant reasons for 
doing so, not the least of which is to do our best through human laws 
to respect the laws of nature and create a safe and healthy world for 
children and future generations who will walk this Earth.
Exhibit E.1: 350 PPM Pathways for the United States (2019), Executive 
        Summary, Evolved Energy Research
May 8, 2019

    Prepared by Ben Haley, Ryan Jones, Gabe Kwok, Jeremy Hargreaves & 
    Jamil Farbes, Evolved Energy Research
    James H. Williams, University of San Francisco, Sustainable 
    Development Solutions Network
Executive Summary
    This report describes the changes in the U.S. energy system 
required to reduce carbon dioxide (CO2) emissions to a level 
consistent with returning atmospheric concentrations to 350 parts per 
million (350 ppm) in 2100, achieving net negative CO2 
emissions by mid-century, and limiting end-of-century global warming to 
1 C above pre-industrial levels. The main finding is that 350 ppm 
pathways that meet all current and forecast U.S. energy needs are 
technically feasible using existing technology, and that multiple 
alternative pathways can meet these objectives in the case of limits on 
some key decarbonization strategies. These pathways are economically 
viable, with a net increase in the cost of supplying and using energy 
equivalent to about 2% of GDP, up to a maximum of 3% of GDP, relative 
to the cost of a business-as-usual baseline. These figures are for 
energy costs only and do not count the economic benefits of avoided 
climate change and other energy-related environmental and public health 
impacts, which have been described elsewhere.\1\
---------------------------------------------------------------------------
    \1\ See e.g., Risky Business: The Bottom Line on Climate Change, 
available at https://riskybusiness.org/.
---------------------------------------------------------------------------
    This study builds on previous work, Pathways to Deep 
Decarbonization in the United States (2014) and Policy Implications of 
Deep Decarbonization in the United States (2015), which examined the 
requirements for reducing GHG emissions by 80% below 1990 levels by 
2050 (``80 x 50'').\2\ These studies found that an 80% reduction by 
mid-century is technically feasible and economically affordable, and 
attainable using different technological approaches. The main 
requirement of the transition is the construction of a low carbon 
infrastructure characterized by high energy efficiency, low-carbon 
electricity, and replacement of fossil fuel combustion with 
decarbonized electricity and other fuels, along with the policies 
needed to achieve this transformation. The findings of the present 
study are similar but reflect both a more stringent emissions limit and 
the consequences of 5 intervening years without aggressive emissions 
reductions in the U.S. or globally.
---------------------------------------------------------------------------
    \2\ Available at http://usddpp.org/.
---------------------------------------------------------------------------
    The 80 x 50 analysis was developed in concert with similar studies 
for other high-emitting countries by the country research teams of the 
Deep Decarbonization Pathways Project, with an agreed objective of 
limiting global warming to 2 C above pre-industrial levels.\3\ 
However, new studies of climate change have led to a growing consensus 
that even a 2 C increase may be too high to avoid dangerous impacts. 
Some scientists assert that staying well below 1.5 C, with a return to 
1 C or less by the end of the century, will be necessary to avoid 
irreversible feedbacks to the climate system.\4\ A recent report by the 
IPCC indicates that keeping warming below 1.5 C will likely require 
reaching net-zero emissions of CO2 globally by mid-century 
or earlier.\5\ A number of jurisdictions around the world have 
accordingly announced more aggressive emissions targets, for example 
California's recent executive order calling for the state to achieve 
carbon neutrality by 2045 and net negative emissions thereafter.\6\
---------------------------------------------------------------------------
    \3\ Available at http://deepdecarbonization.org/countries/.
    \4\ James Hansen, et al., (2017) ``Young people's burden: 
requirement of negative CO2 emissions,'' Earth System 
Dynamics, https://www.earth-syst-dynam.net/8/577/2017/esd-8-577-
2017.html.
    \5\ Available at https://www.ipcc.ch/sr15/.
    \6\ Available at https://www.gov.ca.gov/wp-content/uploads/2018/09/
9.10.18-Executive-Order.pdf.
---------------------------------------------------------------------------
    In this study we have modeled the pathways--the sequence of 
technology and infrastructure changes--consistent with net negative 
CO2 emissions before mid-century and with keeping peak 
warming below 1.5 C. We model these pathways for the U.S. for each 
year from 2020 to 2050, following a global emissions trajectory that 
would return atmospheric CO2 to 350 ppm by 2100, causing 
warming to peak well below 1.5 C and not exceed 1.0 C by century's 
end.\7\ The cases modeled are a 6% per year and a 12% per year 
reduction in net fossil fuel CO2 emissions after 2020. These 
equate to a cumulative emissions limit for the U.S. during the 2020 to 
2050 period of 74 billion metric tons of CO2 in the 6% case 
and 47 billion metric tons in the 12% case. (For comparison, current 
U.S. CO2 emissions are about 5 billion metric tons per 
year.) The emissions in both cases must be accompanied by increased 
extraction of CO2 from the atmosphere using land-based 
negative emissions technologies (``land NETs''), such as reforestation, 
with greater extraction required in the 6% case.
---------------------------------------------------------------------------
    \7\ Hansen, et al., (2017).
---------------------------------------------------------------------------
Figure ES1


          Global surface temperature and CO2 emissions 
        trajectories. Hansen, et al., 2017.

    We studied six different scenarios: five that follow the 6% per 
year reduction path and one that follows the 12% path. All reach net 
negative CO2 by mid-century while providing the same energy 
services for daily life and industrial production as the Annual Energy 
Outlook (AEO), the Department of Energy's long-term forecast. The 
scenarios explore the effects of limits on key decarbonization 
strategies: bioenergy, nuclear power, electrification, land NETs, and 
technological negative emissions technologies (``tech NETs''), such as 
carbon capture and storage (CCS) and direct air capture (DAC).

                                  Table ES1. Scenarios Developed in this Study
----------------------------------------------------------------------------------------------------------------
                                                                                              Year 2050 maximum
                         Average annual rate     2020-2050  maximum     Year 2050 maximum     net CO2 with 50%
       Scenario            of CO2 emission       cumulative fossil     net fossil fuel CO2    increase in land
                              reduction          fuel CO2 (million       (million metric    sink (million metric
                                                    metric tons)              tons)                 tons)
----------------------------------------------------------------------------------------------------------------
              Base                      6%                 73,900                   830                  ^250
                  Low Biomass           6%                 73,900                   830                  ^250
                  Low Electrification   6%                 73,900                   830                  ^250
    No New Nuclear                      6%                 73,900                   830                  ^250
      No Tech NETS                      6%                 73,900                   830                  ^250
                  Low Land NETS        12%                 57,000                  ^200                  ^450
----------------------------------------------------------------------------------------------------------------

    The scenarios were modeled using two new analysis tools developed 
for this purpose, EnergyPATHWAYS and RIO. As extensively described in 
the Appendix,* these are sophisticated models with a high level of 
sectoral, temporal, and geographic detail, which ensure that the 
scenarios account for such things as the inertia of infrastructure 
stocks and the hour-to-hour dynamics of the electricity system, 
separately in each of fourteen electric grid regions of the U.S. The 
changes in energy mix, emissions, and costs for the six scenarios were 
calculated relative to a high-carbon baseline also drawn from the AEO.
---------------------------------------------------------------------------
    * Editor's note: the Our Children's Trust submission for the record 
for this hearing does not include Appendix. It has been reproduced, as 
submitted, herein. The full report (which includes the Appendix) is 
retained in Committee file and is available at: https://
docs.wixstatic.com/ugd/294abc_95dfdf602afe4e11a184ee65ba565e60.pdf.
---------------------------------------------------------------------------
    Relative to 80 x 50 trajectories, a 350 ppm trajectory that 
achieves net negative CO2 by midcentury requires more rapid 
decarbonization of energy plus more rapid removal of CO2 
from the atmosphere. For this analysis, an enhanced land sink 50% 
larger than the current annual sink of approximately 700 million metric 
tons was assumed.\8\ This would require additional sequestration of 25-
30 billion metric tons of CO2 from 2020 to 2100. The present 
study does not address the cost or technical feasibility of this 
assumption but stipulates it as a plausible value for calculating an 
overall CO2 budget, based on consideration of the scientific 
literature in this area.\9\
---------------------------------------------------------------------------
    \8\ U.S. EPA, Inventory of U.S. Greenhouse Gas Emissions and Sinks 
1990-2016, available at https://www.epa.gov/ghgemissions/inventory-us-
greenhouse-gas-emissions-and-sinks-1990-2016.
    \9\ Griscom, Bronson W., et al., (2017) ``Natural climate 
solutions.'' Proceedings of the National Academy of Sciences 114.44 
(2017): 11645-11650; Fargione, Joseph E., et al., (2018) ``Natural 
climate solutions for the United States.'' Science Advances 4.11: 
eaat1869.
---------------------------------------------------------------------------
Figure ES2 


          Four pillars of deep decarbonization--Base case.

    Energy decarbonization rests on the four principal strategies 
(``four pillars'') shown in Figure ES2: (1) electricity 
decarbonization, the reduction in emissions intensity of electricity 
generation by about 90% below today's level by 2050; (2) energy 
efficiency, the reduction in energy required to provide energy services 
such as heating and transportation, by about 60% below today's level; 
(3) electrification, converting end-uses like transportation and 
heating from fossils fuels to low-carbon electricity, so that 
electricity triples its share from 20% of current end uses to 60% in 
2050; and (4) carbon capture, the capture of otherwise CO2 
that would otherwise be emitted from power plants and industrial 
facilities, plus direct air capture, rising from nearly zero today to 
as much as 800 million metric tons in 2050 in some scenarios. The 
captured carbon may be sequestered or may be utilized in making 
synthetic renewable fuels.
    Achieving this transformation by mid-century requires an aggressive 
deployment of low-carbon technologies. Key actions include retiring all 
existing coal power generation, approximately doubling electricity 
generation primarily with solar and wind power and electrifying 
virtually all passenger vehicles and natural gas uses in buildings. It 
also includes creating new types of infrastructure, namely large-scale 
industrial facilities for carbon capture and storage, direct air 
capture of CO2, the production of gaseous and liquid 
biofuels with zero net lifecycle CO2, and the production of 
hydrogen from water electrolysis using excess renewable electricity. 
The scale of the infrastructure buildout by region is indicated in 
Figure ES3.
Figure ES3 


          Regional infrastructure requirements (Low Land NETS 
        scenario).

    Figure ES4 shows that all scenarios achieve the steep reductions in 
net fossil fuel CO2 emissions to reach net negative 
emissions by the 2040s, given a 50% increase in the land sink, 
including five that are limited in one key area. This indicates that 
the feasibility of reaching the emissions goals is robust due to the 
ability to substitute strategies. At same time, the more limited 
scenarios are, the more difficult and/or costly they are relative to 
the base case with all options available. Severe limits in two or more 
areas were not studied here but would make the emissions goals more 
difficult to achieve in the mid-century time frame.
Figure ES4


          2020-2050 CO2 emissions for the scenarios in this 
        study.

    Figure ES5 shows U.S. energy system costs as a share of GDP for the 
baseline case and six 350 ppm scenarios in comparison to historical 
energy system costs. While the 350 ppm scenarios have a net cost of 2-
3% of GDP more than the business as usual baseline, these costs are not 
out of line with historical energy costs in the U.S. The highest cost 
case is the Low Land NETs scenario, which requires a 12% per year 
reduction in net fossil fuel CO2 emissions. By comparison, 
the 6% per year reduction cases are more closely clustered. The lowest 
increase is the Base scenario, which incorporates all the key 
decarbonization strategies. These costs do not include any potential 
economic benefits of avoided climate change or pollution, which could 
equal or exceed the net costs shown here.
Figure ES5


          Total energy system costs as percentage of GDP, modeled (R.) 
        and historical (L.).

    A key finding of this study is the potentially important future 
role of ``the circular carbon economy.'' This refers to the economic 
complementarity of hydrogen production, direct air capture of 
CO2, and fuel synthesis, in combination with an electricity 
system with very high levels of intermittent renewable generation. If 
these facilities operate flexibly to take advantage of periods of 
excess generation, the production of hydrogen and CO2 
feedstocks can provide an economic use for otherwise curtailed energy 
that is difficult to utilize with electric energy storage technologies 
of limited duration. These hydrogen and CO2 feedstocks can 
be combined as alternatives for gaseous and liquid fuel end-uses that 
are difficult to electrify directly like freight applications and air 
travel. While the CO2 is eventually emitted to the 
atmosphere, the overall process is carbon neutral as it was extracted 
from the air and not emitted from fossil reserves. A related finding of 
this work is that bioenergy with carbon capture and storage (BECCS) for 
power plants appears uneconomic, while BECCS for bio-refineries appears 
highly economic and can be used as an alternative source of 
CO2 feedstocks in a low-carbon economy.
    There are several areas outside the scope of this study that are 
important to provide a full picture of a low greenhouse gas transition. 
One important area is better understanding of the potential and cost of 
land-based NETs, both globally and in the U.S. Another is the potential 
and cost of reductions in non-CO2 climate pollutants such as 
methane, nitrous oxide, and black carbon. Finally, there is the 
question of the prospects for significant reductions in energy service 
demand, due to lifestyle choices such as bicycling over cars, 
structural changes such as increased transit and use of ride-sharing, 
or the development of less-energy intensive industry, perhaps based on 
new types of materials.
    ``Key Actions by Decade'' below provides a blueprint for the 
physical transformation of the energy system. From a policy 
perspective, this provides a list of the things that policy needs to 
accomplish, for example the deployment of large amounts of low carbon 
generation, rapid electrification of vehicles, buildings, and industry, 
and building extensive carbon capture, biofuel, hydrogen, and synthetic 
fuel synthesis capacity.
    Some of the policy challenges that must be managed include: land 
use tradeoffs related to carbon storage in ecosystems and siting of low 
carbon generation and transmission; electricity market designs that 
maintain natural gas generation capacity for reliability while running 
it very infrequently; electricity market designs that reward demand 
side flexibility in high-renewables electricity system and encourage 
the development of complementary carbon capture and fuel synthesis 
industries; coordination of planning and policy across sectors that 
previously had little interaction but will require much more in a low 
carbon future, such as transportation and electricity; coordination of 
planning and policy across jurisdictions, both vertically from local to 
state to Federal levels, and horizontally across neighbors and trading 
partners at the same level; mobilizing investment for a rapid low 
carbon transition, while ensuring that new investments in long-lived 
infrastructure are made with full awareness of what they imply for 
long-term carbon commitment; and investing in ongoing modeling, 
analysis, and data collection that informs both public and private 
decision-making. These topics are discussed in more detail in Policy 
Implications of Deep Decarbonization in the United States.
Key Actions by Decade
    This study identifies key actions that are required in each decade 
from now to mid-century in order to achieve net negative CO2 
emissions by mid-century, at least cost, while delivering the energy 
services projected in the Annual Energy Outlook. Such a list inherently 
relies on current knowledge and forecasts of unknowable future costs, 
capabilities, and events, yet a long-term blueprint remains essential 
because of the long lifetimes of infrastructure in the energy system 
and the carbon consequences of investment decisions made today. As 
events unfold, technology improves, energy service projections change, 
and understanding of climate science evolves, energy system analysis 
and blueprints of this type must be frequently updated.
2020s
   Begin large-scale electrification in transportation and 
        buildings.

   Switch from coal to gas in electricity system dispatch.

   Ramp up construction of renewable generation and reinforce 
        transmission.

   Allow new natural gas power plants to be built to replace 
        retiring plants.

   Start electricity market reforms to prepare for a changing 
        load and resource mix.

   Maintain existing nuclear fleet.

   Pilot new technologies that will need to be deployed at 
        scale after 2030.

   Stop developing new infrastructure to transport fossil 
        fuels.

   Begin building carbon capture for large industrial 
        facilities.
2030s
   Maximum build-out of renewable generation.

   Attain near 100% sales share for key electrified 
        technologies (e.g., EVs).

   Begin large-scale production of biodiesel and bio-jet fuel.

   Large scale carbon capture on industrial facilities.

   Build out of electrical energy storage.

   Deploy fossil power plants capable of 100% carbon capture if 
        they exist.

  [] Maintain existing nuclear fleet.
2040s
   Complete electrification process for key technologies, 
        achieve 100% stock penetration.

   Deploy circular carbon economy using DAC and hydrogen to 
        produce synthetic fuels.

   Use synthetic fuel production to balance and expand 
        renewable generation.

   Replace nuclear at the end of existing plant lifetime with 
        new generation technologies.

   Fully deploy biofuel production with carbon capture.
Exhibit E.2: 350 PPM Pathways for Florida (2020), Executive Summary and 
        U.S. data from the Technical Supplement, Evolved Energy 
        Research
October 6, 2020

    Prepared by Ben Haley, Gabe Kwok, and Ryan Jones, Evolved Energy 
    Research
Executive Summary
    This study evaluates multiple scenarios to radically reduce the 
greenhouse gas emissions that result from Florida's energy system, and 
can serve as a tool to inform statewide energy system decisions.
    We detail five technically and economically feasible pathways to 
reduce carbon dioxide emissions and remain within a small enough 
``carbon budget'' to enable a return to 350 parts per million of carbon 
dioxide in the atmosphere by 2100, a level identified by scientists as 
a safe limit necessary to preserve a stable climate. These scenarios 
limit emissions while providing the same energy services for daily life 
and industrial production as the Department of Energy's long-term 
forecast.
    This study builds upon the research conducted by Evolved Energy 
Research and the Sustainability Development Solutions Network (SDSN) 
and published on May 8, 2019, titled 350 PPM Pathways for the United 
States.
Scenarios
    This study evaluates five energy decarbonization \1\ scenarios for 
the energy system of Florida:
---------------------------------------------------------------------------
    \1\ ``Decarbonization'' is the process of removing sources of 
carbon dioxide (and other greenhouse gases) from a system--in this 
case, removing fossil fuel emissions from Florida's energy system.
---------------------------------------------------------------------------
    Central: The least constrained scenario, this uses all options to 
decarbonize the energy system.
    Low Biomass: This scenario reduces the development of new biomass 
feedstocks \2\ by 50%.
---------------------------------------------------------------------------
    \2\ Biomass feedstocks are plant-based and animal-based sources of 
fuel, like trees, grasses, or animal fats, for example.
---------------------------------------------------------------------------
    Low Electrification: This scenario assesses the impact of a delayed 
adoption of electric vehicles and heat pumps.
    100% Renewable Primary: This scenario describes an energy system 
based solely on biomass, wind, solar, hydro, and geothermal sources by 
2050.
    No New Regional Transmission (TX): This scenario limits the 
development of new electricity transmission lines between regions 
within the U.S.
Florida Energy System Results
    Energy decarbonization in Florida relies on four principal 
strategies: (1) Electricity decarbonization requires reducing the 
amount of fossil fuels used for electricity generation, thereby 
reducing the amount of greenhouse gas emissions from every unit of 
electricity delivered by about 95% by 2050; (2) Energy efficiency is 
the reduction in energy required to provide energy services such as 
heating and transportation, and energy use per unit GDP is reduced by 
about 50% below today's level; (3) Electrification involves switching 
energy uses including transportation and building heating off of 
fossils fuels and onto low-carbon electricity, and (4) Capturing carbon 
that would otherwise be emitted from power plants and industrial 
facilities--with the captured carbon either stored permanently 
(sequestered) or used to create fuels like synthetic natural gas or 
synthetic diesel, by combining the carbon with renewably-generated 
hydrogen.
    Figure 1 shows historical and projected energy system costs as a 
share of State Gross Domestic Product (GDP). All scenarios evaluated in 
this study are in line with historical energy costs in Florida and, 
even with decarbonization, energy system costs are anticipated to 
decline as a share of GDP. The highest cost scenario is the 100% 
Renewable Primary pathway due to the emphasis on displacing all fossil 
fuels by 2050, rather than continuing to use some small amount of the 
lowest-cost fossil fuels and capturing and storing the associated 
carbon. The lowest cost scenario is the Central scenario, which allows 
for the most flexibility in terms of key decarbonization strategies.

    Note that the costs within this chart do not reflect any of the 
macroeconomic benefits of transitioning off of fossil fuels, including 
improved air quality, avoided climate impacts (like avoided sea level 
rise), reduced energy price volatility, and energy independence, which 
could equal or exceed the net costs shown here.
Figure 1


          Total energy system costs as percentage of GDP, historical 
        and projected for Florida.
Key Actions by Decade
    Achieving the transition described above is not expensive but 
requires significant changes in public policy. Some of the key policy 
challenges that must be managed in all scenarios include: (a) managing 
tradeoffs between using land for low carbon electricity generation 
(like wind farms and solar arrays) and improving natural carbon storage 
in forests and soils; (b) electricity market designs that maintain 
natural gas generation capacity for reliability while using gas 
generators very infrequently; (c) developing electricity rates that 
incentivize customers to flex their energy use to better match periods 
of electricity surplus and shortage that come with intermittent 
renewables like wind and solar; (d) encourage the development of carbon 
capture industries that can leverage periods of excess electricity 
generation; (e) coordination of planning and policy across sectors that 
previously had little interaction, such as transportation and 
electricity; (f) coordination of planning and policy across 
jurisdictions; (g) mobilizing investment for a rapid low carbon 
transition; and [h]) investing in ongoing modeling, analysis, and data 
collection that informs both public and private decision-making. These 
topics are discussed in more detail in Policy Implications of Deep 
Decarbonization in the United States.
    Achieving this transformation in Florida by mid-century at lowest 
cost requires an aggressive deployment of low-carbon technologies, 
including:
2020s
   Begin large-scale transition to electric technologies in key 
        sectors; moving to electric light duty vehicles and electric 
        heat pumps.

   Use coal fired power plants only when absolutely necessary, 
        prioritizing all other sources of electricity generation first. 
        Begin retiring coal assets.

   Ramp up construction of renewable electricity generation and 
        upgrade electricity transmission where needed.

   Allow strategic replacement of natural gas power plants to 
        support rapid deployment of low-carbon generation. These power 
        plants must be financed with the understanding that they will 
        run very infrequently to provide capacity, not as they are 
        operated today.

   Maintain existing nuclear power plants.

   Pilot new technologies that will need to be deployed at 
        scale after 2030.

   Stop developing new infrastructure to transport and process 
        fossil fuels.

   Begin building carbon capture for large industrial 
        facilities.
2030s
   Maximum build-out of renewable electricity generation.

   Nearly 100% of new vehicle sales and new building heating 
        systems using electric technologies.

   Begin large-scale production of biodiesel and bio-jet fuel.

   Large scale carbon capture on industrial facilities.

   Build out electrical energy storage.

   Deploy new natural gas power plants capable of 100% carbon 
        capture if they exist.

   Maintain existing nuclear power plants.

   Continue to reduce generation from gas-fired power plants.
2040s
   Complete the transition to electric technologies for key 
        sectors; virtually 100% of light duty vehicles and building 
        heating systems run on electricity.

   Produce large volumes of hydrogen for use in freight trucks 
        and fuel production.

   Use synthetic fuel production to balance and expand 
        renewable generation.

   Fully deploy biofuel production with carbon capture.

   Further limit gas generation to infrequent periods when 
        needed for system reliability.
          * * * * *
Technical Supplement
    The following technical supplement shows results for the U.S. as a 
whole as well as scenario figures not shown in the body of the main 
report for Florida.
U.S. Results
Figure 30


          E&I CO2 emissions trajectories--U.S.
Figure 31


          CO2 emissions by final energy/emissions category.
Figure 32 


          Cumulative E&I CO2 emissions trajectories.
Figure 33


          Four pillars of deep decarbonization--U.S.
Figure 34


          Final and primary energy demand for all scenarios from 2021-
        2050--U.S.
Figure 35


          Components of emissions reductions in the Central scenario--
        U.S.
Figure 36


          Components of emissions reductions in the Low Biomass 
        scenario--U.S.
Figure 37


          Components of emissions reductions in the Low Electrification 
        scenario--U.S.
Figure 38


          Components of emissions reductions in the No New Regional TX 
        scenario--U.S.
Figure 39


          Components of emissions reductions in the 100% Renewable 
        Primary scenario--U.S.
Figure 40


          Annual net system cost premium above baseline in $2018 and as 
        % of GDP--U.S.
Figure 41


          Net Change in E&I System Spending--U.S.
Figure 42


          Total energy system costs as % of GDP--historical and 
        projected--U.S.
                                Letter 4
        on behalf of agricultural retailers association, et al.

 
 
 
Hon. David Scott,                    Hon. Glenn Thompson,
Chairman,                            Ranking Minority Member,
House Committee on Agriculture,      House Committee on Agriculture,
Washington, D.C.;                    Washington, D.C.
 

    The farmers, cooperatives, researchers, retailers, seed producers, 
scientists and technology developers represented by the organizations 
signed below appreciate the opportunity to provide a statement for the 
record for the House Agriculture Committee hearing on February 25, 2021 
addressing ``Climate Change and the U.S. Agriculture and Forestry 
Sectors.'' We commend the Committee for addressing this important and 
complex issue. As organizations who embrace the use of crop varieties 
improved through biotechnology and recognize the many benefits this has 
enabled American agriculture to achieve, we want to specifically 
highlight the fact that agricultural biotechnology needs to be a part 
of any climate change discussion. Agriculture has achieved notable and 
well documented environmental improvements through the adoption of crop 
varieties improved through biotechnology that have enabled improved 
tillage practices, improved soil health and greatly reduced greenhouse 
gas (GHG) emissions, to name just a few. We are proud of the 
accomplishments achieved to date but are even more excited about the 
potential environmental benefits and climate change mitigation that 
could be possible through the continued development and adoption of new 
crop varieties improved with the help of innovative breeding methods 
such as gene editing, marker assisted selection, genomic selection and 
genetic engineering; new crop varieties that can produce more with 
less--less water, less land, less inputs.
    We support the ongoing public and private investment in the 
research and development of new breeding methods which have the 
potential to enhance the sustainability of agriculture, the 
environment, and our global food system. In order for U.S. agriculture 
to lead in the future, we must have access to every tool available to 
address pressing challenges caused by climate change such as severe 
weather events and rapidly evolving pests and diseases. We must do this 
while meeting societal expectations for reductions in the use of crop 
inputs and increasing new varieties of healthy and affordable food and 
fiber options. Technology will be helpful in confronting these 
challenges but we believe that biotechnology has demonstrated a unique 
ability to meet these demands.
    Our associations strongly support a regulatory system which fosters 
innovation, values the environmental benefits that crops improved using 
biotechnology enable, and recognizes the long and safe track record of 
plant breeding, and the overwhelming evidence of the safe use of 
genetic engineered plants. Congress should continue to encourage 
Federal agencies to broadly communicate how their policy decisions 
related to new plant varieties enable agriculture and forestry to 
further contribute to climate solutions. In 2020, the United States 
Department of Agriculture called for public input on the Agriculture 
Innovation Agenda to help ``stimulate innovation so that American 
agriculture can achieve the goal of increasing U.S. agricultural 
production by 40 percent while cutting the environmental footprint of 
U.S. agriculture in half by 2050.'' \1\  In a summary of the key 
findings from all of the feedback received, USDA published the 
``Agriculture Innovation Agenda: Scorecard Report.'' A key finding of 
that report was that a primary driver of productivity growth is 
``improvements in animal and crop genetics.'' \2\ Biotechnology is a 
critical tool in plant breeding to enhance the efficiency and efficacy 
of improvements in genetics that will maintain American agriculture as 
the world leader in efficiency and sustainability.
---------------------------------------------------------------------------
    \1\ https://www.usda.gov/aia.
    \2\ Agriculture Innovation Agenda: Scorecard Report, https://
www.usda.gov/sites/default/files/documents/aia-scoreboard-report.pdf, 
page 4.
    Editor's note: the report referred to is also retained in Committee 
file.
---------------------------------------------------------------------------
    The men and women represented by our associations believe in the 
vital contributions that our agriculture community can make to mitigate 
climate change and build toward a more sustainable and equitable food 
system. We believe in science and evidence-based solutions. We must 
acknowledge that scientific innovations, such as agricultural 
biotechnology, have resulted in environmental and societal benefits; 
and must continue to be a part of the comprehensive strategy on climate 
change and U.S. agriculture.
    Thank you again for the opportunity to provide this statement for 
the record.
            Sincerely,


 
 
 
Agricultural Retailers Association   National Association of Wheat
                                      Growers
American Farm Bureau Federation      National Corn Growers Association
American Seed Trade Association      National Cotton Council
American Soybean Association         National Council of Farmer
                                      Cooperatives
American Sugarbeet Growers           National Sorghum Producers
 Association
Beet Sugar Development Foundation    Produce Marketing Association
Biotechnology Innovation             Syngenta
 Organization
Crop Science Society of America      U.S. Canola Association
 

                                Letter 5
           on behalf of american society of agronomy, et al.
March 3, 2021

 
 
 
Hon. David Scott,                    Hon. Glenn Thompson,
Chairman,                            Ranking Minority Member,
House Committee on Agriculture,      House Committee on Agriculture,
Washington, D.C.;                    Washington, D.C.
 

    RE: Climate Change and the U.S. Agriculture and Forestry Sectors, 
            Outside Witness Testimony

    Dear Chair Scott and Ranking Member Thompson:

    The American Society of Agronomy (ASA), Crop Science Society of 
America (CSSA), and Soil Science Society of America (SSSA) represent 
more than 8,000 scientists in academia, industry, and government, 
12,500 Certified Crop Advisers (CCA), and 781 Certified Professional 
Soil Scientists (CPSS). We are the largest coalition of professionals 
dedicated to the agronomic, crop and soil science disciplines in the 
United States.
    The House Agriculture Committee's timely hearing on Climate Change 
demonstrates what the Societies also know--that agriculture and 
forestry are the linchpins of America's fight against climate change. 
Agricultural and forest soils have the potential to sequester enough 
carbon to make America carbon neutral, if not a carbon sink. American 
agriculture represents about ten percent of the country's greenhouse 
gas emissions, and agriculture accounts for nearly twenty-five percent 
of emissions globally.\1\ It does not need to be this way. Farmed soils 
have between 25 and 75 percent less carbon than undisturbed soils, 
which means that agriculture has the potential to be a significant 
carbon sink,\2\ providing as much as 0.2 Gt CO2 equivalents 
per year by 2050.\3\ American farmers can become globally recognized 
climate heroes by sequestering more than \1/5\ of U.S. carbon 
emissions, all without interfering with food production.\4\ Forest 
activities, such as reforestation, improved forest management, and 
reduced deforestation have the potential for even greater carbon 
sequestration. The technical potential for carbon uptake by forest 
measures is estimated to be from 0.5 to 1.5 Gt CO2 
equivalents per year by 2050. Forest managers and agroforestry 
producers along with farmers and rangers are poised to deliver enormous 
emissions reductions and offsets from elsewhere in the economy.
---------------------------------------------------------------------------
    \1\ https://www.epa.gov/ghgemissions/sources-greenhouse-gas-
emissions, https://www.epa.gov/ghgemissions/global-greenhouse-gas-
emissions-data#Sector
    \2\ Lal, Rattan. ``Managing soils and ecosystems for mitigating 
anthropogenic carbon emissions and advancing global food security.''  
BioScience 60.9 (2010): 708-721.
    Editor's note: entries annotated with  are retained in Committee 
file.
    \3\ E. Larson, et al. ``Net-Zero America: Potential Pathways, 
Infrastructure, and Impacts, interim report.''  Princeton University, 
Princeton, NJ. December 15, 2020.
    \4\ Fargione, Joseph E., et al. ``Natural climate solutions for the 
United States.''  Science Advances 4.11 (2018): eaat1869.
---------------------------------------------------------------------------
    Rural Americans have a strong voice in Congress through this 
Committee, but the fact that many rural Americans see environmental 
protection as destructive to their very livelihoods and way of life is 
an existential liability for the planet. We urge the Committee to 
quickly implement science-based policies that curb and mitigate climate 
change's effects while empowering producers with new tools, new sources 
of income, and the pride that comes from global recognition of their 
efforts.
Put Carbon Into Soil
Carbon-Rich Farms Are Healthy Farms
    Sequestering carbon on farmland is critical to maintaining a 
healthy planet for generations to come. Sustainable agriculture that 
focuses on a broad, systems approach that returns carbon to the soil 
and builds soil organic matter has the double effect of pulling carbon 
out of the atmosphere and building healthier soils.\5\ Soils with more 
organic matter absorb and retain more moisture, reducing the need for 
irrigation and increasing a farm's resilience to the damage associated 
with droughts or flooding.\6\ More specifically, farms with high soil 
organic matter require fewer additional fertilizers and can produce 
healthier crops and higher yields.\7\
---------------------------------------------------------------------------
    \5\ Lal, Rattan. ``Enhancing crop yields in the developing 
countries through restoration of the soil organic carbon pool in 
agricultural lands.'' Land Degradation & Development 17.2 (2006): 197-
209.
    \6\ Basche, Andrea. ``Turning Soils Into Sponges: How Farmers Can 
Fight Floods and Droughts.''  UCS, editor Washington, DC (2017): 1-18.
    \7\ Lal, Rattan. ``Soil carbon sequestration impacts on global 
climate change and food security.''  Science 304.5677 (2004): 1623-
1627.
---------------------------------------------------------------------------
Awareness of Best Practices Is Key
    Practices to sequester carbon include: no or low tillage; cover 
crops; diverse crop rotations, sometimes including grazing animals; 
land applications of manure, biosolids or urban compost; and precision 
agriculture.\8\ These techniques are based in science, but widespread 
adoption in the United States is hampered by a variety of factors, one 
of which is awareness. The U.S. Department of Agriculture (USDA) and 
universities use Extension agents on a county level to deliver 
knowledge discovered through research to the farmers who can directly 
apply it on their land, but funding for Extension in real dollars has 
declined, as has the number of Extension agents available to farmers. 
Congress should triple the funds for conservation technical assistance 
to empower a new Climate Conservation Corps, with NRCS, Certified Crop 
Advisors, and university Extension employees serving as the boots-on-
the-ground to help farmers transition to a new carbon economy.
---------------------------------------------------------------------------
    \8\ Montgomery, D.R. (2017). Growing a revolution: bringing our 
soil back to life. WW Norton & Company.
---------------------------------------------------------------------------
Make Sure Techniques Are Cost-Effective
    Concern over potential extra costs associated with switching to 
new, unfamiliar systems can be alleviated by USDA programs. For 
example, USDA could be funded to develop a cloud-based cover crop 
support tool that is easy to use, freely available nationally, and 
locally specific. The tool would give detailed recommendations for 
which crops to plant, seeding rates, and more. It would also provide 
long-term economic data for transitions to demonstrate a producer's 
likely return on investment, and, given adherence to its 
recommendations, USDA could offer loans that cover extra costs and 
potential lost income for the first 5 years to promote implementation. 
Once a transition is achieved, USDA could reduce insurance rates for 
the farm's now less risky, more resilient system. Crop insurance 
subsidies that are more generous and flexible to producers engaging in 
sustainable practices will encourage these practices and, subsequently, 
reduce risk.\9\ So as not to disadvantage producers who have already 
made investments in cover crops, for farmers who have already have a 5 
year or longer history of successful cover crop management experience, 
insurance premiums can be reduced to offset a portion of their 
investment and to not leave these pioneering early adopters behind. 
Important to note, these interventions become exponentially more 
effective with access to broadband, making rural connectivity a key 
driver to enabling sustainable practices.
---------------------------------------------------------------------------
    \9\ Pan, William L., et al. ``Integrating Historic Agronomic and 
Policy Lessons with New Technologies to Drive Farmer Decisions for Farm 
and Climate: The Case of Inland Pacific Northwestern U.S.''  Frontiers 
in Environmental Science 5 (2017): 76.
---------------------------------------------------------------------------
Carbon Markets Require Scientific Legitimacy
    Congress should consider policies that facilitate ecosystem 
services markets for producers to earn money directly from sequestering 
carbon, reducing emissions, preventing erosion, enhancing water 
quality, and improving the viability of carbon land sinks in both 
agricultural and forested lands. Such a market needs to be created and 
maintained with the most up-to-date science. Science is always moving 
forward--new information is constantly discovered, but this must not 
impede a market from forming now, nor should such a market be prevented 
from incorporating new findings as they come. Investments in ecosystems 
science, which includes, for example, soil science, agronomy, forestry, 
and data science working together, will inform a trusted market that 
accurately measures and values ecosystem services. Importantly, a lack 
of science underpinning such a market will greatly degrade trust in its 
value. This would lead not only to the system's demise but it could 
also doom future plans to pay producers for ecosystem services, even if 
subsequent ideas are defensible.
    Hundreds of millions of dollars per year in soil and forestry 
research are needed over the next decade to establish ecosystem health 
benchmarks so that best practices can be developed for producers over 
wide geographic ranges. There are proven means of management-based soil 
carbon sequestration,10-12   but which practices have the 
largest impact, and where these practices can be optimized, is 
essential information for valuing ecosystem credits. Also necessary are 
rapid soil tests that validate these benchmarks. USDA's National 
Institute of Food and Agriculture (NIFA) should carve out funding for 
research on soil and forest health and the sustainable, systems-based 
approaches that return carbon to the soil and build soil organic 
matter. Congress should fully fund AgARDA with a mandate to invest in 
high-risk and complex, systems-level research for improving carbon land 
sinks.
---------------------------------------------------------------------------
    \10\ Poeplau, Christopher, and Axel Don. ``Carbon sequestration in 
agricultural soils via cultivation of cover crops--A meta-analysis.'' 
Agriculture, Ecosystems & Environment 200 (2015): 33-41.
    \11\ Luo, Zhongkui, Enli Wang, and Osbert J. Sun. ``Can no-tillage 
stimulate carbon sequestration in agricultural soils? A meta-analysis 
of paired experiments.''  Agriculture, Ecosystems & Environment 139.1-
2 (2010): 224-231.
    \12\ McDaniel, M.D., L.K. Tiemann, and A.S. Grandy. ``Does 
agricultural crop diversity enhance soil microbial biomass and organic 
matter dynamics? A meta-analysis.''  Ecological Applications 24.3 
(2014): 560-570.
---------------------------------------------------------------------------
Invest in Conservation
Expand Conservation Programs Like the Conservation Reserve Program 
        (CRP) and the Environmental Quality Incentives Program (EQIP)
    Congress has decided that for some lands, the ecological impacts of 
farming outweigh the potential economic benefit to the producer. The 
Conservation Reserve Program (CRP) is an option Congress gives 
producers that pays them to take this land out of production and to 
restore forests and grasslands. But producers may decide that the 
potential profit made by planting crops could outweigh the CRP 
payments, compelling producers to plant on land better suited to 
conservation. Congress should adjust CRP guidelines to incentivize 
conservation under a variety of economic circumstances. The guidelines 
should also be amended to focus primarily on the marginal lands the 
program was intended to protect, while lands better suited to 
production should be channeled to the Environmental Quality Incentives 
Program (EQIP). EQIP is an excellent way to provide funding for 
conservation practices on working lands, but it is oversubscribed. 
Congress should allocate more funding for this program.
Water and Irrigation Research Helps Producers and Preserves Natural 
        Ecosystems
    Agriculture accounts for approximately 80 percent of freshwater use 
in the United States \13\ because irrigation can double or even triple 
grain yields in managed agriculture.\14\ But even as irrigation helps 
producers grow more food on less land, extreme weather events and 
increased development put pressure on freshwater resources. Research on 
improved regional irrigation strategies and on crops that require less 
water is key. This research has the combined benefit of helping 
producers withstand droughts and floods while preserving more 
freshwater for natural ecosystems and human consumption.\15\
---------------------------------------------------------------------------
    \13\ https://www.ers.usda.gov/topics/farm-practices-management/
irrigation-water-use/.
    \14\ Kukal, Meetpal, and Suat Irmak. ``Irrigation-limited yield 
gaps: trends and variability in the United States post-1950.''  
Environmental Research Communications (2019).
    \15\ Basche, Andrea D., and Marcia S. DeLonge. ``Comparing 
infiltration rates in soils managed with conventional and alternative 
farming methods: a meta-analysis.''  BioRxiv (2019): 603696.
---------------------------------------------------------------------------
Diverse Crops And Markets Make Resilient Farms
    As new weather patterns change which crops producers can grow, 
science needs to step in with new options to keep farms resilient. 
Research is needed to help current commodity crops adapt, but producers 
and their lands will benefit from a new generation of climate-resilient 
crops that are better at carbon sequestration and nitrogen use 
efficiency and more tolerant of droughts and floods. USDA can partner 
with universities and industry to breed these desperately needed crops. 
AQUAmax corn and perennial grain crops, for example, are promising new 
options. Research and partnerships to produce these crops rely on the 
USDA National Plant Germplasm System and USDA gene banks, which 
preserve and develop plant genetic resources, such as 
seeds.16-17   The genetic resources contained in USDA gene 
banks will be utilized more intensively, both for adapting existing 
crops and for introducing new crop species or crop uses to changing and 
more variable environments.
---------------------------------------------------------------------------
    \16\ Gepts P. (2006) Plant genetic resources conservation and 
utilization: The accomplishments and future of a societal insurance 
policy. Crop Science 46: 2278-2292 doi: 10.2135/
cropsci2006.03.0169gas.
    \17\ Byrne P.F., Volk G.M., Gardner C., Gore M.A., Simon P.W., 
Smith S. (2018) Sustaining the future of plant breeding: the critical 
role of the USDA-ARS National Plant Germplasm System. Crop Science 58: 
451-468 doi: 10.2135/cropsci2017.05.0303.
---------------------------------------------------------------------------
    Crop diversification will require expanded markets and market 
diversification, enabling producers to weather crop price fluctuations, 
and diverse crop rotations are a tenant of a soil health-centered 
agriculture--a win-win for both producers and climate.\18\ Agronomic 
research should widen to include a multitude of crops, agroecoforestry, 
and the investments needed in economics, marketing, and outreach to 
prepare for commercial production and expand their markets. Perennial 
crops, such as perennial grain crops, for example, have the potential 
to sequester carbon year after year while saving producers money in 
seeds and planting and enhancing biodiversity,\19\ but market 
infrastructure is key to ensuring profitability at comparable levels to 
current commodities.
---------------------------------------------------------------------------
    \18\ Pan, William L., et al. ``Integrating Historic Agronomic and 
Policy Lessons with New Technologies to Drive Farmer Decisions for Farm 
and Climate: The Case of Inland Pacific Northwestern U.S.''  Frontiers 
in Environmental Science 5 (2017): 76.
    \19\ Glover, Jerry D., et al. ``Increased food and ecosystem 
security via perennial grains.''  Science 328.5986 (2010): 1638-1639.
---------------------------------------------------------------------------
Expand On-Farm Energy Production Through Biofuel Systems
    Biofuels play an important role in meeting global energy demands, 
but many crops traditionally used for bioethanol production, such as 
corn (maize), sugarcane, and sugar beets, are more valuable as food and 
feed sources. Because the priorities of energy and food are in constant 
competition, these types of biofuel crops will not be able to meet 
rising global energy demands. Instead, investments are needed to 
research and deploy biofuel systems that use agricultural residues and 
food waste while promoting sustainable land use.\20\
---------------------------------------------------------------------------
    \20\ Gupta, Anubhuti, and Jay Prakash Verma. ``Sustainable bio-
ethanol production from agro-residues: a review.'' Renewable and 
Sustainable Energy Reviews 41 (2015): 550-567.
---------------------------------------------------------------------------
Nitrogen Management Research Benefits the Planet and the Producer's 
        Bottom Line
    The use of industrially produced nitrogen fertilizers on farms has 
saved billions from starvation and substantially reduced the amount of 
land that would have been cleared for agriculture. But applied nitrogen 
that a crop does not use immediately can lead to contaminated 
waterways, causing ``dead zones'' and ``do not drink'' water 
advisories. Excess nitrogen in the soil also converts to the potent 
greenhouse gas nitrous oxide,21-22   which causes three 
hundred times more global warming than carbon dioxide.
---------------------------------------------------------------------------
    \21\ Canfield, Donald E., Alexander N. Glazer, and Paul G. 
Falkowski. ``The evolution and future of Earth's nitrogen cycle.''  
Science 330.6001 (2010): 192-196.
    \22\ Snyder, C.S., et al. ``Agriculture: sustainable crop and 
animal production to help mitigate nitrous oxide emissions.''  Current 
Opinion in Environmental Sustainability 9 (2014): 46-54.
---------------------------------------------------------------------------
    Researchers are discovering new ways to reduce nitrogen 
applications without compromising yields. Precision agriculture, for 
example, is a promising technology powered by artificial intelligence 
that requires rural broadband for high-speed wireless connectivity. It 
combines best practices with on-farm data and digitally enabled 
equipment so that fertilizers can be applied according to variabilities 
across a field. This represents a major paradigm shift from managing an 
entire field the same way. Meanwhile, management techniques take 
advantage of rotations with crops that produce, or ``fix,'' their own 
nitrogen from the air, and a recent discovery of nitrogen fixation in a 
corn (maize) landrace represents a huge potential for reducing nitrogen 
applications worldwide,\23\ should researchers harness its potential in 
commercial varieties.
---------------------------------------------------------------------------
    \23\ Van Deynze, Allen, et al. ``Nitrogen fixation in a landrace of 
maize is supported by a mucilage-associated diazotrophic microbiota.'' 
 PLoS Biology 16.8 (2018): e2006352.
---------------------------------------------------------------------------
Research and Extension Are Vital
    Agricultural producers need healthy soils that sequester carbon, 
resist flooding, and retain moisture; they need Extension experts and 
Certified Crop Advisors who can rapidly bring them up to speed on the 
latest best practices; they need cost-effective policies that 
incentivize conservation and follow the latest science; and they need 
resilient crops and robust markets for them. Each of these needs can be 
met with increased investments in Extension and agricultural and 
forestry research on soil and ecosystem health, agricultural and 
forestry best practices, and a diversity of crops. Resilient, 
sustainable farms, forests, and ranches of the future must be our 
legacy.
    Thank you for your consideration. For additional information or to 
learn more about the ASA, CSSA, and SSSA please contact Karl Anderson, 
Director of Government Relations, Redacted or Redacted. We look forward 
to hearing from the Committee on how our membership's expertise can 
help farmers become climate heroes.

Cc: Members of the House Agriculture Committee.
                                Letter 6
                 biotechnology innovation organization
February 25, 2021

 
 
 
Hon. David Scott,                    Hon. Glenn Thompson,
Chairman,                            Ranking Minority Member,
House Committee on Agriculture,      House Committee on Agriculture,
Washington, D.C.;                    Washington, D.C.
 

    Dear Chairman Scott, Ranking Member Thompson, and Members of the 
Committee:

    The Biotechnology Innovation Organization (BIO) is pleased to 
submit a statement for the record to the to the United States House of 
Representatives Committee on Agriculture hearing entitled, ``Climate 
Change and the U.S. Agriculture and Forestry Sectors.''
Introduction
    BIO\1\ represents 1,000 members in a biotech ecosystem with a 
central mission--to advance public policy that supports a wide range of 
companies and academic research centers that are working to apply 
biology and technology in the energy, agriculture, manufacturing, and 
health sectors to improve the lives of people and the health of the 
planet. BIO is committed to speaking up for the millions of families 
around the globe who depend upon our success. We will drive a 
revolution that aims to cure patients, protect our climate, and nourish 
humanity.
---------------------------------------------------------------------------
    \1\ https://www.bio.org/.
---------------------------------------------------------------------------
Fighting Climate Change Through Biotechnology Innovation
    BIO applauds the Committee for putting its immediate focus on the 
climate crisis. As we outline in our attached ``100 Days of 
Innovation'' Blueprint \2\ (Appendix I), our nation is at a critical 
juncture. The start of the new administration and new Congress presents 
a unique opportunity to come together to galvanize our nation's 
scientific and entrepreneurial capacity, to mobilize new waves of 
homegrown innovation and American ingenuity to tackle the climate 
crisis, end the pandemic, and get more Americans back to work.
---------------------------------------------------------------------------
    \2\ https://archive.bio.org/sites/default/files/docs/toolkit/
BIO_100_Days_of_Innovation.pdf.
---------------------------------------------------------------------------
    COVID-19 has also exposed the vulnerabilities and inequalities in 
how communities are disproportionately impacted, our capacity to 
respond to crisis, our ability to maintain our supply chains, and to 
withstand an economic downturn. These challenges will only grow more 
prevalent and damaging because of climate change.
    To meet the challenge of climate change, it is crucial to lead with 
science and U.S. innovation. We must incentivize the adoption of 
innovative, sustainable technologies and practices; and streamline and 
expedite regulatory pathways for breakthrough technology solutions. 
Investment and deployment of cutting-edge technologies will be crucial 
to ensure farmers, ranchers, sustainable fuel producers, and 
manufacturers are able to respond to climate change and maintain the 
U.S.'s global leadership in agriculture. This includes removing 
barriers and assisting beginning and socially disadvantaged farmers and 
ranchers to access and utilize these technologies, so all producers can 
adapt to the challenges ahead. By accelerating and deploying 
innovation, American agriculture can be resilient, self-sustaining, and 
drive our economic recovery.
    BIO supports legislative action on climate change that catalyzes 
resilient and sustainable biobased economies. Federal climate policy 
should use science-based targets to increase the use of biobased 
manufacturing, low-carbon fuels, and sustainable agricultural 
solutions. Science-based policy will promote resilient and sustainable 
supply chains across economic sectors including translating 
sustainability to best practices to all bioindustries. If done right, 
climate legislation will create market pull incentives for investment 
in and use of innovative technologies and products that fight climate 
change.\3\ This will enable U.S. agriculture to combat climate change 
while producing enough food, feed, fuel, and fiber for a growing world.
---------------------------------------------------------------------------
    \3\ https://www.bio.org/strategic-vision.
---------------------------------------------------------------------------
Biotech Achievements
    The adoption of biotechnology in agriculture and the development of 
biobased technologies has already contributed to food security, 
sustainability, and climate change solutions. The acceptance of 
biotechnology has enabled large shifts in agronomic practices that have 
led to significant and widespread environmental benefits. Some biotech 
climate solutions include:

   Biotech crops, such as those that require no-tilling, have 
        saved 27.1 billion kg of carbon dioxide, equivalent to taking 
        16.7 million cars off the road.\4\
---------------------------------------------------------------------------
    \4\ https://www.isaaa.org/resources/publications/briefs/54/
executivesummary/default.asp.
    Editor's note: entries annotated with are retained in Committee 
file.

   Synthetic biology enables farmers to enhance soil health to 
        grow more food on less land, manufacturers to create new food 
        ingredients and alternative proteins, and industrial biotech 
        companies to revolutionize manufacturing by optimizing 
        processes for producing sustainable chemicals, biobased 
        products, and biofuels.\5\
---------------------------------------------------------------------------
    \5\ https://www.bio.org/blogs/synthetic-biology-sustain-
agriculture-and-transform-food-system.

   The use of feed additives for ruminant livestock, has been 
        demonstrated to reduce methane levels produced by ruminants by 
        up to 30 percent \6\ while the addition of enzymes \7\ to 
        chicken feed promotes better protein digestibility, which helps 
        reduce residual nitrogen emissions from manure.
---------------------------------------------------------------------------
    \6\ https://newfoodeconomy.org/feed-additive-methane-cow-burps/.
    \7\ https://www.novozymes.com/en/news/news-archive/2017/03/more-
from-one-acre-new-report.

   New research \8\ shows emissions from sustainable fuels made 
        from corn are 46 percent lower than gasoline. Advanced and 
        cellulosic biofuel technologies can reduce emissions from 101 
        to 115 percent.\9\
---------------------------------------------------------------------------
    \8\ https://iopscience.iop.org/article/10.1088/1748-9326/abde08.
    \9\ https://www.eesi.org/articles/view/biofuels-versus-gasoline-
the-emissions-gap-iswidening#:
:targetText=Argonne%20researchers%20show%20that%20compared, 
for%20the%20RFS%20from
%202010.

   Renewable chemicals and biobased products removed 12.7 
        million metric tons of CO2 from the manufacturing 
        sector in 2016 alone, and can continue to green our supply 
        chains, reduce plastic pollution, and provide sustainable 
        alternatives to fossil-based products.\10\
---------------------------------------------------------------------------
    \10\ https://www.biopreferred.gov/BPResources/files/
BiobasedProductsEconomicAnalysis
2018.pdf.

    To learn more about these technologies and the innovative 
breakthroughs that can reduce greenhouse gas emissions throughout 
agricultural supply chains, please see BIO's attached comments \11\ 
(Appendix II) to the U.S. Department of Agriculture's (USDA) 
Solicitation of Input from Stakeholders on Agricultural 
Innovations.\12\
---------------------------------------------------------------------------
    \11\ https://www.bio.org/letters-testimony-comments/bio-submits-
comments-usda-ag-innovation.
    \12\ https://www.govinfo.gov/content/pkg/FR-2020-04-01/pdf/2020-
06825.pdf.
---------------------------------------------------------------------------
Policy Recommendations
    As the Committee and Congress examine policies to combat climate 
change, while also aiming to strengthen the economy and create jobs, 
BIO recommends the following policy approaches:

   Incentivize Modern Ag Techniques. Enable America's farmers, 
        ranchers, and foresters to combat climate change by 
        incentivizing the adoption of modern agricultural techniques 
        and innovative technologies, including carbon sequestration, 
        enhancing animal feed with enzymes, microbes to reduce 
        emissions from livestock, precision plant breeding, and 
        biostimulants and microbial inoculants--which boost production 
        by building up soil carbon and using less fertilizer. This also 
        includes:

     Helping producers solve the technical entry barriers 
            to participating in carbon credit markets as proposed in 
            the Growing Climate Solutions Act.

     Incentivizing farm management decisions that have 
            large impact on reducing GHG emissions and increasing soil 
            organic carbon, such as expanding section 45Q of the Tax 
            Code to credit.

     Bolster U.S. Department of Agriculture (USDA) 
            conservation programs to promote improved soil health and 
            carbon sequestration.

   Certify Sustainable Ag Practices. Create a certification 
        program at USDA to allow producers to participate in carbon 
        credit markets which will enable the manufacturers of biobased 
        fuels, chemicals, plastics, food, animal feed, veterinary 
        products, and everyday materials to reliably demonstrate their 
        true environmental benefit--from farm to consumer.

   Promote Animal Biotechnology Innovations. Genetic innovation 
        in animals can help prevent and respond to future infectious 
        diseases. These technologies hold enormous potential to address 
        numerous agricultural, environmental, humanitarian, and public 
        health challenges associated with climate change by enabling 
        animal agriculture to produce more protein with fewer animals 
        and adapting livestock to a warming world. We need to 
        streamline oversight of animal biotechnology to create a clear, 
        timely, and science-based regulatory approval process that 
        provides a viable path to market for these critical new 
        innovations.

   Streamline Approval Process for Innovative Feed Additives. 
        Feed additives are key for promoting robustness and resilience 
        in livestock through improved nutrition. Furthermore, they 
        improve the return on investment for farmers and reduce 
        greenhouse gas emissions. Unfortunately, many of these new 
        innovative products lack a suitable regulatory product category 
        to ensure timely approval nationwide. An improved regulatory 
        process is necessary to bring these innovative technologies to 
        market to address climate change.

   Modernize Evaluation of Veterinary Products. Disruptive 
        innovations and advances in veterinary products can increase 
        protein production while decreasing emissions from livestock. 
        To better account for these environmental benefits, the U.S. 
        Food and Drug Administration and USDA's methods to evaluate the 
        efficacy of these technologies must also evolve to properly 
        measure the climate and sustainability improvements they 
        provide.

   Boost Access to Nutrition. Utilize technology to boost the 
        nutrient levels of fruits and vegetables. Biotech enables crops 
        to maintain yields in the face of drought and less water, which 
        has a direct bearing on improved food security and poverty 
        alleviation. Increased production from biotechnology crops can 
        help combat global hunger and malnutrition by increasing the 
        vitamin and mineral contents of plants.

   Eliminate Food Deserts and Reduce Food Waste. Incentivize 
        the use of biotech in specialty crops to address the lack of 
        fresh fruits and vegetables in food deserts in urban and rural 
        communities. Biotech advancements allow for fewer blemishes, 
        such as bruises, that lead to more sellable crops for farmers 
        requiring less acreage. These technologies can also extend the 
        shelf life of produce, cutting down on food waste, which 
        creates eight percent of all global emissions.* [1] 
        Ensure biotech products are used to achieve the U.S. 
        Environmental Protection Agency (EPA) and USDA's Food Loss and 
        Waste Reduction Goal in alignment with Target 12.3 of the UN 
        Sustainable Development Goal to reduce food waste by 50 percent 
        by 2030. Additionally, support the development of bioplastics 
        from sustainable chemicals that can be recyclable, 
        biodegradable, or compostable to divert food packaging waste 
        from landfills.
---------------------------------------------------------------------------
    * Editor's note: the footnote reference in the document as 
submitted is [1]. This is an endnote reference format, the extraneous 
formatting is retained herein.
    [1] http://www.fao.org/fileadmin/templates/nr/
sustainability_pathways/docs/FWF_and_cli
mate_change.pdf

   Ensure Regulatory and Government Support Keep Pace with 
        Technology Advancements. Innovations like synthetic biology, 
        gene editing, cell culturing, and fermentation hold tremendous 
        potential to solve urgent challenges throughout the 
        agricultural supply chain which will only be compounded by 
        climate change. Producers and developers will need access to 
        these innovative technologies to increase production while 
        cutting down on their environmental footprint. Enabling 
        regulatory systems to keep pace with advancements in biology is 
        essential if society is expected to fully benefit from food, 
        health, and industrial products developed using the very latest 
        cutting-edge platform technologies. Furthermore, domestic 
        regulatory pathways must provide for more expedient approval 
        timelines to ensure the economics of new product development 
        are not a deterrent to bringing new products to market. In the 
        absence of a predictable and well-designed regulatory product 
        approval system developers may choose to invest in more mature 
        markets with better approval timelines. Investments by the 
        government in next generation of biotechnologies and genomics 
---------------------------------------------------------------------------
        will also be critical to meet the challenge of climate change.

   Support Federal Biobased Procurement and Sustainability 
        Programs to Buy ``Green''. Enhance USDA Biopreferred program to 
        ensure that agencies are fulfilling their obligation to shop 
        Biopreferred. While the program has been successful in 
        certifying products over the years, procurement agencies have 
        not been held accountable to buy Biopreferred options where 
        available.

      Also critical to the development of the biobased economy is 
        determining its value and identifying the segments which need 
        investment and research and development. Key to this is 
        updating the North American Industry Classification System 
        (NAICS) codes to establish measurements for biobased products 
        as required under the 2018 Farm Bill.

   Accelerate Public and Private Research and Development to 
        Drive Investment in New Tools. Provide significant advances in 
        foundational tool development and practical applications 
        through supportive grants for research and development of new 
        tool start-ups. Foster coordination across agencies to advance 
        research and development in biomanufacturing, strengthening and 
        broadening the U.S.' synthetic biology capabilities and 
        developing the future bioeconomy workforce.

   Expand incentives for Carbon Capture Utilization, and 
        Sequestration. This technology presents a significant 
        opportunity to transform the manufacturing sector and reduce 
        greenhouse gas emission by turning carbon into value added 
        products. Extend and expand incentives to support carbon 
        utilization and innovative technologies to bolster the 
        potential of direct air capture technologies. USDA should 
        develop a verification methodology suitable for products of 
        biological carbon capture and utilization (CCU) to expand 
        opportunities for U.S. biomanufacturing as directed by the 2018 
        Farm Bill.

   Incentivize green manufacturing infrastructure. Spur 
        investment and development of biobased manufacturing through 
        supportive grants and tax incentives.

   Develop a Federal Low Carbon Fuel Standard (LCFS). A LCFS 
        that is technology and feedstock neutral and builds on the 
        success of the Renewable Fuel Standard (RFS) to ensure 
        agriculture and low carbon, sustainable fuels are part of the 
        solution will significantly reduce emissions in transport.

   Incentivize Advanced and Cellulosic Fuel Development. 
        Ensuring the growth of advanced and cellulosic biofuels 
        industry will require long-term tax incentives to avoid 
        creating uncertainty for investors and companies trying to 
        raise capital. The development of a long-term sustainable 
        aviation fuel specific blender's tax credit could attract 
        significant investment and address existing structural and 
        policy disincentives that have prevented the aviation biofuels 
        industry from taking off.

   Bring New Sustainable Fuel Technologies to Market and 
        Recognize Environmental Benefit. Direct the EPA to approve 
        stalled pathways and facility registrations for advanced and 
        cellulosic biofuel technologies to spur investment and 
        development in sustainable fuels projects as proposed in S. 
        193. Because of biotech innovations, the production of biofuels 
        is becoming more efficient and environmentally sustainable. To 
        reflect these improvements, EPA should update its greenhouse 
        gas modeling as proposed in S. 218.

   Investment in Research and Development and Grants to Develop 
        and Deploy Advanced Biofuels. To spur investment and 
        development of new biorefineries and deployment of advanced 
        biofuels, USDA's Biorefinery Assistance program and the 
        Department of Energy research and development programs should 
        be feedstock neutral. Investments in USDA's Higher Blends 
        Infrastructure Incentive Program (HBIIP) will help consumers 
        access low carbon fuels.

   One Health Approach to Public Health Preparedness. One 
        Health represents a much-needed collaboration that would align 
        human health, animal health, and environmental health 
        strategies to create smarter, multifaceted, and coordinated 
        efforts, including to help enhance the ability of our planet to 
        adapt to climate change. The thoughtful and bipartisan 
        Advancing Emergency Preparedness Through One Health Act (S. 
        1903/H.R. 3771) from the 116th Congress directs the U.S. Health 
        and Human Services and USDA to coordinate with other agencies 
        and state and local leaders to advance a national One Health 
        framework to better prevent, prepare for, and respond to 
        zoonotic disease outbreaks like COVID-19. Doing so will help 
        insulate human populations from future infectious diseases, 
        antimicrobial resistance (AMR), and other heath challenges 
        arising from climate change.

   Advance Global Climate Solutions. Build broad global support 
        for the U.S. government's recent regulatory modernization for 
        agricultural biotechnology and proactively advance 
        biotechnology as a valuable tool to combat climate change 
        through broad trade strategy approaches and efforts to reengage 
        in multilateral forums.
Conclusion
    BIO is committed to working with the Committee, Congress, and the 
Administration to address the climate crisis. We urge you to support 
policy that advances pioneering technology breakthroughs. With science 
we can return our nation and the world to health and prosperity by 
taking bold and drastic action to address the climate crisis.
Appendix I
100 Days of Innovation
    Our nation is at a critical juncture and how we approach the next 
100 days will be essential in terms of ending the pandemic and 
rebuilding our economy in a way that is more resilient, more dynamic, 
and more inclusive. America remains the most vibrant and 
entrepreneurial nation in the world. We have been tested time and time 
again and have always emerged stronger and more united. As the new 
Administration and new Congress begin, there is a unique opportunity 
for the private and public sectors to come together to galvanize our 
nation's scientific and entrepreneurial capacity, to mobilize new waves 
of homegrown innovation and American ingenuity and to organize our 
country around the clear and bold mission of ending the pandemic and 
getting more American's back to work. To do that we must:

  1.  Ensure a Speedy Transition and an Expedited Senate Confirmation 
            Process for Agency Leadership Critical to Advancing Public 
            Health, Nutrition, and Environmental Goals.

  2.  Reengage as a Leader on the World Stage, Including Rejoining the 
            World Health Organization and the Paris Climate Accords.

  3.  Develop and Approve More Vaccines, Therapeutics, and Diagnostics 
            To Prevent and Treat COVID-19[:]

      Specific Recommendations

       Provide increased R&D funding for a broad array of 
            innovative technologies 
              with the potential to fight COVID-19 and other emerging 
            infectious dis-
              eases.

       Ensure ample funding to complete research priorities and 
            procurement of 
              existing vaccines and therapeutics.

       Expand government coordination mechanisms beyond the 
            first wave of 
              COVID-19 vaccines, treatments, and diagnostics.

       Encourage more public-private partnerships and private 
            investment 
              through sound public policy.

       Continue expedited EUA and full approval processes for 
            existing and next 
              wave of COVID vaccines and therapies.

       Ensure that companies can continue to partner with HHS, 
            BARDA and 
              DOD without regard to their current global supply chain.

       Increase funding for CDC surveillance activities to help 
            evaluate the effec-
              tiveness of COVID vaccines and therapeutics and drive 
            evidence-based deci-
              sion making on development of updated or new medical 
            countermeasures.

  4.  Promote Robust and Equitable Patient Access to COVID-19 Vaccines, 
            Therapeutics, and Diagnostics[:]

      Specific Recommendations

       Eliminate all patient cost-sharing across government and 
            commercial insur-
              ance markets for COVID-related vaccines, treatments, and 
            diagnostics, in-
              cluding for administration and ancillary services.

       Ensure state Medicaid programs cover all FDA-approved 
            COVID-19 treat-
              ments and diagnostics, including those approved under an 
            EUA, without 
              delay and without prior authorization requirements.

       Cover COVID-19 treatment for the uninsured via Medicaid 
            at 100% 
              Federal match.

       Ensure that provider relief funds and other similar 
            assistance is targeted 
              to providers who serve Medicaid, the uninsured, and other 
            vulnerable pa-
              tients.

       Expand and adequately fund the range of sites 
            administering COVID-19 
              vaccines and treatments beyond acute care settings, 
            including home infu-
              sion of therapeutics.

       Mount a coordinated and well-funded national campaign to 
            build vaccine 
              confidence and facilitate vaccination, particularly in 
            minority communities 
              and among essential workers.

       Develop a national vaccination plan to accelerate 
            distribution and adminis-
              tration of COVID-19 vaccines in an equitable manner.

       Leverage Federal research funding to diversify Federal 
            clinical trial net-
              works and promote minority inclusion in COVID-19 trials.

       Encourage governors to expand the vaccine eligible 
            populations to the ACIP 
              recommendations expediently.

  5.  Better Prepare for Future Infectious Disease Outbreaks[:]

      Specific Recommendations

       Support a steady-state of public and private R&D on 
            emerging infectious 
              diseases by providing tax incentives for private 
            investment in early-stage 
              clinical R&D of medical countermeasures.

       Adequately fund and resource agencies engaged in 
            biodefense and emer-
              gency preparedness such as ASPR, BARDA, USDA, and the 
            CDC, so they 
              have the infrastructure in place for immediate response 
            and can improve 
              long-term strategic preparedness planning.

       Enable the creation, maintenance, and utilization of 
            advanced manufac-
              turing capabilities domestically, particularly for 
            biological products by 
              incentivizing private investment in facilities and 
            equipment, supporting ini-
              tiatives for training a new and expanded workforce, and 
            ensuring a clear 
              regulatory pathway.

       Increase physical and virtual inventories of critical 
            emergency supplies in 
              the Strategic National Stockpile.

       Pursue a ``One Health'' coordination approach across the 
            government that 
              recognizes the interrelationship between human, animal, 
            and environ-
              mental health.

       Rebuild and invest in the state and local public health 
            infrastructure.

  6.  Drive Economic Revival and BIO's Pledge Resiliency Through 
            Adoption of Advanced Biotechnology Solutions[:]

      Specific Recommendations

       Develop streamlined and expedited regulatory pathways 
            for breakthrough 
              technology solutions to climate change and nutrition 
            challenges.

       Expand support for scale-up of biorefineries and other 
            biobased manufac-
              turing.

       Incentivize the adoption of sustainable agricultural 
            practices and low-car-
              bon fuels.

       Enforce requirements that Federal agencies should be 
            purchasing biobased 
              products--``Buy Green America.''

       Incentivize the use of existing or future COVID-19 
            relief and recovery fund-
              ing to purchase biobased products to meet the demand for 
            personal protec-
              tion equipment (PPE), sterilizing and cleaning equipment 
            and cleaning 
              products, and with respect to broader efforts to ``build 
            back better.''

       In addition to these immediate actions, BIO calls on the 
            Federal Govern-
              ment, working with state, local, and private-sector 
            partners, to conduct a 
              comprehensive review of COVID outbreak and pandemic 
            response to iden-
              tify additional steps that could/should have been taken 
            or that could im-
              prove the nation's response and recovery in the future.
BIO's Pledge
    Working With Our Member Companies and Other Partners, BIO Will:

   Expand covidvaccinefacts.org to provide the public with 
        easily understandable, transparent, and credible information 
        about the safety and efficacy of COVID-19 vaccines and how they 
        can obtain access to them.

   Facilitate cooperative agreements to expand manufacturing 
        capabilities of vaccines to meet the demand.

   Promote continued diversity in COVID clinical trials.

   Always stand up for science.

   Highlight steps being taken by the Administration, Congress, 
        and BIO's member companies to resolve the COVID-19 pandemic in 
        BIO's public communication portals, meetings and events.
Appendix II
July 31, 2020

    Hon. Sonny Perdue,
    Secretary,
    U.S. Department of Agriculture,
    Washington, D.C.

    Re: U.S. Department of Agriculture Solicitation of Input from 
            Stakeholders on Agricultural Innovations (Docket No. USDA-
            2020-0003)

    Dear Secretary Purdue,

    The Biotechnology Innovation Organization (BIO) is pleased to 
respond to the U.S. Department of Agriculture's (USDA) Solicitation of 
Input from Stakeholders on Agricultural Innovations.\1\
---------------------------------------------------------------------------
    \1\ https://www.govinfo.gov/content/pkg/FR-2020-04-01/pdf/2020-
06825.pdf.
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    BIO represents 1,000 members from the biotech ecosystem around a 
central mission--to advance public policy that supports a wide range of 
companies and academic research centers that are applying biology and 
technology to improve the lives of people and the health of the planet. 
Our members operate at the nexus of environmental, human, and animal 
health. They are developing biology-based technologies to enhance 
cultivation and food production and produce sustainable fuels, 
renewable chemicals, and biobased products. With our growing 
understanding of the plant, animal, and microbial worlds and supportive 
policies and regulations we can modernize agriculture, energy, and 
manufacturing.
    These innovative breakthroughs can reduce greenhouse gas emissions 
throughout agricultural supply chains and strengthen producers 
resiliency to climate change while increasing production and help 
tackling hunger by bringing more nutritious offerings to all tables; 
and protect against this pandemic and the next by enhancing the 
response to public health emergencies and speed the transition of the 
U.S. economy to one that is more biobased and resilient. Already, 
innovative technologies have been widely adopted to increase 
productivity while reducing the footprint of agricultural production. 
Increasing use and acceptance of these technologies will enable U.S. 
agriculture to meet the Department's goal set forth in the Agriculture 
Innovation Agenda (AIA) of increasing agricultural production by 40 
percent to meet the needs of the global population in 2050 while 
cutting the environmental footprint in half.
    The U.S. has led the way in developing these innovations due to 
thoughtful, bipartisan public policy. This has created a favorable 
climate in which to undertake the lengthy and risky job of investing 
and developing the next biotech breakthroughs; allowed producers to use 
new technologies; and ensured a pathway to market for new products. 
However, America's continued success and leadership are not guaranteed, 
and it should not take its global leadership for granted. Foreign 
countries are taking overt steps to streamline regulatory systems and 
speed pathways to market, often with direct government support as part 
of national bioeconomy strategies.
    COVID-19 has also exposed the vulnerabilities and inequalities in 
how communities are disproportionately impacted, our capacity to 
respond to crisis, our ability to maintain our supply chains, and to 
withstand an economic downturn. These challenges will only grow more 
prevalent and damaging because of climate change. To ensure America is 
able to respond to future challenges in cleaner, more efficient ways, 
maintain its global leadership, and allow its farmers, ranchers, 
sustainable fuel producers, and manufacturers to have access to cutting 
edge technologies, the United State must invest in new technologies and 
have risk-proportionate regulations that spur biological innovations. 
The government should also focus on removing barriers and assisting 
beginning and socially disadvantaged farmers and ranchers in accessing 
and utilizing these technologies, so all producers can adapt to the 
challenges ahead. By accelerating and deploying innovation American 
agriculture can be resilient, self-sustaining, and drive our economic 
recovery.
    Below are five key drivers for successful growth of the bioeconomy 
and to enable U.S. agriculture to meet the Department's goals set forth 
in AIA:

  1.  Advance Modern Regulatory Approaches to Keep Pace with Innovation

        Innovative biotechnologies have allowed producers to increase 
            crop yields, enhance food animal production, improve soil 
            health, and provide biomass and waste feedstocks for 
            sustainable fuels and biobased manufacturing. Expanding the 
            adoption of innovative technologies and practices that 
            reduce the environmental footprint of agriculture while 
            combatting climate change will be necessary to provide the 
            world with adequate food, feed, fuel, and fiber.
        As such, it is critical that the government establish risk-
            proportionate, transparent regulations that spur biological 
            innovations while protecting health and the environment. 
            Enabling regulatory systems to keep pace with advancements 
            in biology is essential if society is expected to fully 
            benefit from food, health, and industrial products 
            developed using the very latest cutting-edge platform 
            technologies; such as, gene editing, synthetic biology, 
            cell culturing, and fermentation.

  2.  Provide Robust Funding of Public and Private Sector Scientific 
            Research

        We must foster an innovation ecosystem that unleashes the 
            transformative potential of science and take steps to 
            ensure the gains from these innovations are broadly shared 
            for the benefit of humanity. This research and development 
            will require the strong support of land-grant universities 
            and Historically Black Colleges and Universities (HBCUs), 
            to produce and develop young scientists and engineers 
            critical to moving the industry forward.
        Federal research programs under USDA's National Institute of 
            Food and Agriculture (NIFA) Agriculture and Food Research 
            Initiative (AFRI) have been fundamental to the applied 
            research, extension, and education of food and agricultural 
            sciences to improve rural economies and create new sources 
            of energy. These programs have been essential for the 
            foundational research and agricultural workforce 
            development that complements and underpins large systems-
            level research, education, and extension activities needed 
            to maintain America's global preeminence in food, 
            agricultural, and bioenergy production.
        Other Federal Government research and development programs have 
            been essential to the development of clean energy 
            technologies that strengthen the economy, protect the 
            environment, and reduce dependence on foreign oil. While 
            there has been increasing research and development in 
            biotechnology platform technologies--such as gene editing, 
            synthetic biology, cell culturing, and fermentation--
            increased Federal funding and coordination between agencies 
            will be critical to maintain America's leadership in an 
            increasingly competitive race to generate breakthroughs. 
            The new innovations unlocked from supportive scientific 
            research and development will enable agriculture to 
            increase production while reducing greenhouse gas emissions 
            across agriculture, transportation, and industry.

  3.  Modernize Infrastructure

        Ensuring farmers and ranchers can deploy innovative 
            technologies that increase production to create a resilient 
            bioeconomy while reducing pollution will also require 
            important investments in infrastructure. This includes, but 
            is not limited to increased lab capacity, widespread access 
            to broadband internet technology, pipelines and 
            distribution capacity for carbon dioxide and sustainable 
            fuels. It will also require the government working with 
            financial institutions and investors to promote access to 
            capital for startups and scaleup in the biobased 
            manufacturing sectors across agricultural, energy, and 
            material products.

  4.  Incentivize Farmers

        Supporting America's farmers, ranchers, and foresters who want 
            to adopt new technologies and innovative practices will be 
            critical to USDA achieving the goals set forth in the AIA. 
            To foster sustainability and economic resiliency in 
            agriculture and preserve America's rich environmental 
            diversity all producers must have access to and benefit 
            from new markets that reward practices for reducing the 
            environmental impact of agriculture.

  5.  Build Public Support and Increase Market Access for Innovative 
            Technologies

        Innovation flourishes when science and consumer values are 
            aligned and complement one another. BIO understands that 
            consumers want more information about innovative 
            biotechnologies; to know what is in their food and whether 
            their food is safe. Moreover, it should be clear that 
            biofuels and biobased products are sustainable. As such, 
            the government must help build trust and foster an 
            inclusive environment to address our most pressing 
            societal, nutritional, and environmental concerns to 
            achieve the goals put forward in the AIA.

    The following comments expands on these principles, highlights 
existing and developing technologies describing how increasing the 
utilization of biological innovations will enable U.S. agriculture to 
meet the Department's goals set forth in AIA for the betterment of 
society.
Table of Contents
Advance Modern Regulatory Approaches to Keep Pace with Innovation

    I. Food and Farm Applications
    II. Sustainable Fuels
    III. Biobased Manufacturing

Provide Robust Funding of Public and Private Sector Scientific Research

    I. Invest in Agricultural Research
    II. Sustainable Fuels
    III. Biobased Manufacturing
    IV. Investing in Platform Technologies

Modernize Infrastructure

    I. Access to Broadband
    II. Grants
    III. Investments in Biofuels Infrastructure
    IV. Tax Incentives
    V. Bolstering the Supply Chain

Incentivize Farmers

    I. Carbon Sequestration
    II. Incentivizing New Technologies

Build Public Support and Increase Market Access for Innovative 
Technologies

    I. Build Public Support and Market Access

Conclusion
Advance Modern Regulatory Approaches to Keep Pace with Innovation
I. Food and Farm Applications
Plant Biotech--Plant Biotech Innovations Benefits
    Biotech crops have already contributed to food security, 
sustainability, and climate change solutions. The acceptance of 
biotechnology has enabled large shifts in agronomic practices that have 
led to significant and widespread environmental benefits. No-till 
agriculture has been widely adopted due to the superior weed control 
from biotech crops that are able to tolerate the newer class of lower-
impact herbicides. In addition, a reduction in plowing has also enabled 
farmers to significantly lower the consumption of fuel and decrease 
greenhouse gas emissions. No-till farming also leads to better 
conservation of soil and water and a decrease in soil erosion and soil 
compaction. Biotechnology has also made possible pest control measures 
that are more precisely targeted at specific problem pests while 
dramatically reducing impacts on non-target species. According to the 
International Service for the Acquisition of Agri-biotech Applications 
(ISAAA) \2\ biotech-enhanced farming systems saved 452 million acres of 
lands from plowing and cultivation, and decreased use of pesticides by 
8.2 percent since 1996.
---------------------------------------------------------------------------
    \2\ http://www.isaaa.org/resources/publications/briefs/54/
executivesummary/default.asp.
    * 
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    Biotech has also enabled plants maintain yields in the face of 
drought and less water. While high-yielding biotech crops have a direct 
bearing on improved food security and poverty alleviation with 
increased production. As highlighted by the United Nations 
biotechnology can contribute to combating global hunger and 
malnutrition. Approximately 140 million children in low-income groups 
are deficient in Vitamin A. This situation has compounded into a public 
health challenge. The World Health Organization reports that an 
estimated 250,000 to 500,000 Vitamin A-deficient children become blind 
every year, half of them dying within 12 months of losing their sight. 
Golden Rice, a crop produced using the tools of biotechnology, contains 
three new genes that helps it to produce provitamin A.\3\ Because of 
these benefits, 150 Nobel Laureates and 13,270 scientists and citizens 
wrote in support of crops and foods improved through biotechnology.\4\
---------------------------------------------------------------------------
    \3\ https://unchronicle.un.org/article/biotechnology-solution-
hunger.
    \4\ https://www.supportprecisionagriculture.org/nobel-laureate-gmo-
letter_rjr.html.
---------------------------------------------------------------------------
    As great as these developments have been towards enabling 
agriculture to increase production while reducing its environmental 
impact; developing and deploying new innovations in crop production 
will be critical in adapting to the challenges brought on by climate 
change[.]
Future Plant Biotech Opportunities
    Gene editing is a process scientists use to make targeted 
modifications to a plant's DNA to strengthen the plant. Gene editing is 
the most recent breakthrough in a continuum of breeding methods that 
have been used to develop more beneficial food, fiber, and fuel for 
centuries. Our growing understanding of DNA allows this to happen in 
years, rather than decades. In many cases, the changes made through 
gene editing could happen naturally through an evolutionary process, 
making the gene-edited plant the same or very similar to products 
developed through other existing breeding methods.\5\
---------------------------------------------------------------------------
    \5\ https://innovature.com/basics.
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    Gene editing can fast track genetic improvements in food, fiber, 
and fuel crops to keep pace with global warming and a growing human 
population \6\ and enable growers to produce higher yields with lower 
fertilizer, water, and nitrogen inputs.\7\ Environmental stressors 
cause $14 to $19 billion in plant losses every year. The single biggest 
cause of those losses is limited water, and that will likely get worse 
with climate change.\8\ This technology can help us create more 
resilient crops able to withstand more variable weather events due to 
climate change by increasing plant tolerance to heat, floods, salinity, 
droughts and extreme cold.
---------------------------------------------------------------------------
    \6\ https://www.nytimes.com/2019/06/17/science/food-agriculture-
genetics.html#click=https://t.co/yb95Eso0kY.
    \7\ https://innovature.com/article/dr-kasia-glowacka-plants-may-
thrive-less-water.
    \8\ https://www.nsf.gov/awardsearch/showAward?AWD_ID=0820126.
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    Climate change will also exacerbate crop loss from insects by 10 to 
25 percent because insect populations and their appetites surge in warm 
temperatures.\9\ However, researchers are using gene editing to limit 
the threat to crops. Gene edited insects, like the genetically modified 
diamondback moths have the potential to reduce wild pest 
populations.\10\ Gene editing hold great potential help plants become 
more resilient to a range of environmental stressors including pest and 
disease. As an example, the deadly fungus--Fusarium oxysporum Tropical 
Race 4 (TR4)--has decimated banana plantations in southeast Asia for 30 
years and has made its way to Latin America.\11\ However, gene editing 
is being used to create a banana resistant to TR4. Not only can this 
technology create disease-resistant varieties, it can also bring more 
genetic diversity to the fruit to mitigate future disease.\12\
---------------------------------------------------------------------------
    \9\ https://science.sciencemag.org/content/361/6405/916.
    \10\ https://www.cnn.com/2020/01/29/us/genetically-engineered-
moths-crop-protection-study-scn/index.html.
    \11\ https://www.wired.co.uk/article/banana-disease-tr4-latin-
america.
    \12\ https://www.bio.org/blogs/bananas-are-brink-extinction-gene-
editing-can-reverse.
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    Gene editing can also boost the nutrient levels of fruits and 
vegetables. Increasing the vitamin and mineral contents of plants, 
particularly staple crops, such as, potatoes, corn, soybeans, and wheat 
can address hunger issues globally and, in the U.S., where large 
portions of the population do not meet their nutrient requirements.\13\
---------------------------------------------------------------------------
    \13\ https://innovature.com/article/dr-taylor-wallace-gene-editing-
could-mean-healthier-foods-and-healthier-planet.
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    Incentivizing the utilization of biotech in specialty crops can 
also help address the lack of fresh fruits and vegetables in food 
deserts in urban and rural communities. Consumers are already enjoying 
non-browning features in apples and potatoes. Extending the shelf life 
of produce can increase the availability of fruits and vegetables.
    Not only will this innovation make nutritional food more available 
to consumers, it will cut down on food waste. According to USDA, in 
2018 Americans threw away roughly 150,000 tons of food each day with 
fruits and vegetable accounting for 40 percent of that total.\14\ 
Globally, the U.N. Food and Agriculture Organization (FAO) \15\ 
estimates that worldwide, the amount of food wasted is enough to feed 
two billion people--more than double the number of people struggling 
with hunger. The global carbon footprint of all this wasted food was 
about 3.3 billion tons of carbon-dioxide equivalents, seven percent of 
all global emissions.\16\ Using technology to cut down on food waste 
can help us address hunger and tackle climate change.
---------------------------------------------------------------------------
    \14\ https://journals.plos.org/plosone/article?id=10.1371/
journal.pone.0195405.
    \15\ https://www.wfpusa.org/articles/8-facts-to-know-about-food-
waste-and-hunger/.
    \16\ https://www.washingtonpost.com/news/energy-environment/wp/
2016/03/28/the-enormous-carbon-footprint-of-the-food-we-never-eat/.
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    Synthetic biology also has major potential to improve agricultural 
production. Using tools in the synthetic biology toolbox, scientists 
typically stitch together long stretches of DNA and insert them into an 
organism's genome.\17\
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    \17\ https://www.genome.gov/about-genomics/policy-issues/Synthetic-
Biology.
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    Innovations like gene editing and synthetic biology hold tremendous 
potential to solve urgent challenges in agriculture which will only be 
compounded by climate change. Producers will need access to these 
innovative technologies to increase production while cutting down on 
their environmental footprint. Ensuring regulatory systems keep pace 
with these advancements will be essential for agricultural production 
to keep up with a growing population while reducing the environmental 
impacts.
Modernize Plant Biotech Regulations
    A regulatory climate that fosters innovation is an important 
component to ensuring the development and deployment of tools producers 
will need for meeting the agricultural and environmental challenges in 
the future. A 2011 study found that between 2008-2012, bringing a new 
plant biotechnology trait to market cost $136 million and took 
approximately 13.1 years, with regulatory requirements accounting for 
more than \1/3\ of the time required. The study also projected these 
costs and timeframes to increase in future years.\18\ These costly 
barriers for market entry have historically prohibited the 
participation of many academics and small- and medium-sized businesses 
in this sector and has unfortunately limited the deployment of these 
innovations to crops where these significant costs can be recouped.\19\
---------------------------------------------------------------------------
    \18\ https://croplife.org/wp-content/uploads/pdf_files/Getting-a-
Biotech-Crop-to-Market-Phillips-McDougall-Study.pdf.
    \19\ https://www.cast-science.org/publication/regulatory-barriers-
to-the-development-of-innovative-agriculturalbiotechnology-by-small-
businesses-and-universities/.
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Executive Order on Modernizing the Regulatory Framework for 
        Agricultural Biotechnology Products (E.O. 13874)
    BIO appreciates the Administration and USDA's efforts to create a 
predictable, streamlined, science-based regulatory system to spur 
investment in and deployment of innovative solutions. Last year's 
Executive Order on Modernizing the Regulatory Framework for 
Agricultural Biotechnology Products (E.O. 13874) \20\ set forth agency 
reforms that could facilitate the growth of technological innovation in 
agriculture for the foreseeable future. E.O. 13874 builds on calls to 
improve the regulatory process that has spanned multiple 
administrations.\21\
---------------------------------------------------------------------------
    \20\ https://www.whitehouse.gov/presidential-actions/executive-
order-modernizing-regulatory-frameworkagricultural-biotechnology-
products/.
    \21\ https://obamawhitehouse.archives.gov/sites/default/files/
microsites/ostp/2017_coordina
ted_framework_update.pdf.
---------------------------------------------------------------------------
SECURE Rule
    USDA's Animal and Plant Health Inspection Service (APHIS) Final 
Rule for biotechnology regulations, 7 CFR part 340, issued on May 14, 
2020 also helps ensure that regulations keep up with innovation. 
Referred to as the SECURE rule,\22\ which stands for Sustainable, 
Ecological, Consistent, Uniform, Responsible, Efficient, is the first 
comprehensive revision of APHIS' biotechnology regulations since they 
were established in 1987.
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    \22\ https://www.usda.gov/media/press-releases/2020/05/14/usda-
secure-rule-paves-way-agricultural-innovation.
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    BIO, overall, supports the USDA's final revisions to its plant 
biotechnology regulatory system. USDA has an excellent track record 
regulating plant biotechnology based on science and risk. The final 
rule acknowledges a history of safe use of plant biotechnology and the 
similarity of many gene edited plants to those derived from 
conventional breeding techniques.\23\
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    \23\ https://archive.bio.org/sites/default/files/docs/toolkit/
USDA_Part_340_Issue_Brief_FI
NAL.pdf?_ga=2.217235934.974532664.1591207008-377855674.1537910566
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Regulatory Barriers to Address
    The SECURE rule is a meaningful step forward in fostering 
innovation, enabled by its use of exemptions for certain, familiar, and 
low-risk plants and adoption of a new, more efficient risk assessment 
system. However, the lengthy timeframe over which the new rules will be 
implemented, and relatively narrow exemptions will delay development 
and commercialization for many innovative products. Those issues will 
need to be resolved going forward to ensure that innovative products 
face a clear, risk-based timely path to market. Visibly absent from 
this rule however were any revisions to the part 340 regulatory systems 
for future advances relevant to non-plant GE organisms. Also, because 
the SECURE rule allows developers to self-certify exemption from USDA 
regulations without notifying the agency, the rule raises issues 
related to transparency about products entering the marketplace. As 
discussed in more detail later in our comments, BIO will continue to 
drive a process to develop an inclusive and impactful approach to 
transparency for biotechnology in food and agriculture.
Microbial Biotech--Benefits of Microbial Technology in Farm, Food, and 
        Feed Applications
    Farm

    Synthetic biology can be used in a variety of ways to reduce 
agriculture's environmental impact. One example is through the 
development of soil microbes.\24\ Globally four percent of greenhouse 
gases are attributed to making ammonia, nitrogen fertilizer. When 
applied, half goes to crops and half ends up in water due to runoff. 
This excess nitrogen runoff can lead to ``dead zones'' in our large 
lakes and oceans.\25\ Plants like soybeans and other legumes have 
microbes in their roots that take on this chemical engineering process 
naturally fertilizing themselves. Corn, wheat, and rice, which make up 
half the global fertilizer usage do not have these microbes. Using 
synthetic biology you can take the DNA code from the microbes in 
soybeans, redesign it to work with the microbes in corn.\26\ Then you 
apply it as a seed treatment, and it will fertilize that crop so you 
can wean corn off fertilizer over time. By creating the right 
combination of microbes, scientists can make more resilient, efficient 
cropping systems.\27\
---------------------------------------------------------------------------
    \24\ https://www.bio.org/blogs/synthetic-biology-sustain-
agriculture-and-transform-food-system.
    \25\ https://www.bloomberg.com/news/features/2019-11-06/ginkgo-
bioworks-ceo-wants-biology-to-manufacture-physical-goods.
    \26\ https://onezero.medium.com/how-microbes-could-upend-americas-
toxic-dependence-on-nitrogen-fertilizer-548451117a63.
    \27\ https://innovature.com/article/microbes-nourish-plants-
naturally.
---------------------------------------------------------------------------
    Plant biostimulants can improve a plant's natural nutritional 
processes, which results in enhanced tolerance to abiotic and other 
environmental stresses that improves overall plant health, growth, 
quality, and yield. In doing so, these products can increase the uptake 
and utilization of existing and applied nutrients. Plant biostimulants 
also can increase yield and quality without increasing applied 
fertilizer, water, or expanding planted acres, thus, sustainably 
enhancing the efficient use of these inputs and natural resources. 
Comprehensively, these technologies will not only result in a 
significant reduction in agriculture's climate and water-quality 
footprint, but it is a win-win for farmers, as the costs for their crop 
inputs and labor needs would decrease.

    Food

    Altering microbes with synthetic biology also gives us new ways to 
sustainably develop food ingredients. Vanillin--one of the most popular 
synthetic ingredients in the world--makes up 99 percent of vanilla 
flavoring consumed but relies on coal and oil mining to produce. 
Through synthetic biology we can make vanillin that is molecularly 
identical to the bean without burning fossil fuels.\28\ Separately, 
using synthetic biology to edit brewer's yeast to produce hemoglobin is 
key to the development of new alternative proteins.\29\ This is the 
base technology that makes product taste like meat, i.e., the high 
concentration of heme, gives meat its signature texture and is key to 
several alternative meats such as the impossible burger.
---------------------------------------------------------------------------
    \28\ https://wholefoodsmagazine.com/columns/debates/synthetic-
biology-key-to-a-healthier-planet-or-threat-to-organic/.
    \29\ https://www.bio.org/blogs/synthetic-biology-sustain-
agriculture-and-transform-food-system.
---------------------------------------------------------------------------
    Using microbials and synthetic biology, we can boost nature's 
ability to grow more food on less land and create food ingredients 
without harming the environment.

    Feed

    Applications of biology-based innovation to animal feed holds 
potential for providing additional agricultural solutions. Enteric 
fermentation from ruminant animals--such as cows, sheep, goats, and 
buffalo are a major contributor of greenhouse gas emissions from 
agriculture. These animals, which use microflora to assist in the 
digestion of otherwise indigestible starchy plants, such as grasses, 
produce significant volumes of methane as a byproduct of the digestive 
process.\30\
---------------------------------------------------------------------------
    \30\  http://www.fao.org/in-action/enteric-methane/background/what-
is-enteric-methane/en/.
---------------------------------------------------------------------------
    Despite trends in plant-based protein, animal protein production is 
not expected to decrease any time soon. Not only has U.S. consumption 
of meat and poultry continued to increase,\31\ but global animal 
protein consumption is expected to jump 15 percent by 2027, especially 
in areas with growing global middle classes with increased access to 
disposable income.\32\ Due to methane's high, short-term global warming 
potential compared to CO2, solutions are immediately needed 
to facilitate this expansion sustainably.
---------------------------------------------------------------------------
    \31\ https://www.nationalchickencouncil.org/about-the-industry/
statistics/per-capita-consumption-of-poultry-and-livestock-1965-to-
estimated-2012-in-pounds/.
    \32\ https://www.agri-pulse.com/articles/11933-plant-based-animal-
protein-demand-shows-no-sign-of-letting-up.
---------------------------------------------------------------------------
    Existing innovations, such as feed additives for ruminant 
livestock, have been demonstrated to reduce methane levels in ruminant 
animals by up to 30 percent.\33\ The addition of enzymes \34\ to 
chicken feed promotes better protein digestibility, which helps reduce 
residual nitrogen emissions from manure. While probiotics \35\ in 
animal feed help improve gut health of the animal. Using methanotrophs 
and other microorganisms, such as E. coli, have also demonstrated the 
feasibility of converting natural gas and methane into proteins for 
animal feed. Where feasible, anaerobic digestion can be applied to 
convert manure and other carbonaceous wastes into renewable natural 
gas. However, many of these post-excrement solutions are not practical 
for free range ruminates. Innovation in ruminant feeds and animal 
genetics will be critical to expand upon these environmental benefits 
as growth in animal protein continues.
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    \33\ https://newfoodeconomy.org/feed-additive-methane-cow-burps/.
    \34\ https://www.novozymes.com/en/news/news-archive/2017/03/more-
from-one-acre-new-report.
    \35\ https://www.novozymes.com/en/advance-your-business/
agriculture/animal-health-nutrition/product/alterion.
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Regulatory Barriers to Address
    Barriers to Microbial Technologies

    While the SECURE Rule will help streamline the deployment of 
innovative plant technologies, it has created uncertainty for microbial 
technology. Under the previous regulations. developers of innovative 
microbial products could confirm whether a particular product was 
subject to regulation using USDA's ``Am I Regulated Process.'' The 
SECURE rule provides less certainty and fewer mechanisms for evaluating 
whether a product is subject to regulation, resulting in an unclear and 
uncertain regulatory process for microbial products of biotechnology.
    BIO requested in its comments \36\ on the proposed rule, Movement 
of Certain Genetically Engineered Organisms \37\ develop, propose, and 
implement a plan to facilitate research, develop, and commercialize 
non-plant GE organisms, including microbes and insects. The comment 
noted failure to do so will create a significant competitive 
disadvantage for these products and delay their introduction to the 
market.
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    \36\ https://www.bio.org/sites/default/files/2020-04/
BIO%20Comments%20on%20340FNL%20
080519.pdf
    \37\ https://www.federalregister.gov/documents/2019/06/06.
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    The SECURE rule is lacking a clear and predictable regulatory 
framework for non-plant GE organisms potentially subject to part 340. 
This uncertainty has significant potential to slow research, 
development, and commercialization of entire categories of innovative 
agricultural products with the potential to present novel lasting 
solutions to some of agriculture's most pressing challenges.
    Accordingly, BIO urges APHIS to promptly develop and issue guidance 
for non-plant GE organisms' potentially subject to regulation under 
Part 340. Without guidance, developers of non-plant GE organisms will 
lack any semblance of clear, predictable, risk-based regulatory 
options. In the absence of leadership from USDA companies may choose to 
commercialize their product in countries with a more predictable 
regulatory framework and path to commercialization. APHIS, should 
ensure any movement restrictions imposed on non-plant organisms, 
whether microorganisms or invertebrates, should be based on the fact 
that the organism itself poses plant pest risk and not on the fact that 
the non-plant is used to control plant pests.

    Regulatory uncertainty with feed additives

    As for feed additives, many of these new innovative products lack a 
suitable regulatory product category for timely approval of solutions 
that improve animal health without being veterinary drugs. For example, 
if a feed additive were to address methane emissions from cattle, that 
product would require one of three regulatory pathways. One is GRAS 
(Generally Recognized As Safe) notice to FDA, which will take an 
estimated 2 years for approval and limits the claims that can be made. 
Two is an Association of American Feed Control Officials (AAFCO) new 
ingredient definition submission, which may take between 3 and 5 years, 
and would limit the types of claims the feed producer could make. Three 
is a Food Additive Petition with FDA's Center for Veterinary Medicine 
(CVM), which may also take 3 to 5 years for approval and would also 
limit the claims the producer could make because it is not a full drug 
approval. None of these pathways offer the kind of quick assessment 
that is necessary to bring innovation to market to address climate 
change. Faster assessment route for these technologies will be critical 
in addressing emissions from livestock.

    Animal Biotech

    The outbreak of COVID-19 has brought to light the 
interconnectedness between human and animal health. Like the current 
coronavirus, scientists estimate that more than six out of every ten 
known infectious diseases in people can be spread from animals, and 
three out of every four new or emerging infectious diseases in people 
come from animals.\38\ In addition to the dreadful health implications, 
the resulting economic costs of a pandemic are profound. The World Bank 
estimates that, between 1997 and 2009, the global costs from six 
zoonotic outbreaks exceeded $80 billion.\39\ COVID-19 has already 
produced one of the sharpest economic downturns in U.S. history and is 
costing the U.S. treasury alone trillions of dollars.
---------------------------------------------------------------------------
    \38\ https://www.cdc.gov/onehealth/basics/zoonotic-diseases.html.
    \39\ http://documents.worldbank.org/curated/en/612341468147856529/
pdf/691450ESW0whit
0D0ESW120PPPvol120web.pdf.
---------------------------------------------------------------------------
    The U.S. was woefully unprepared for this pandemic. We must employ 
modern approaches to be ready for future outbreaks. Improvement of 
animal genetics will also be a critical aspect to helping livestock 
producers around the world adapt to climate change, develop resiliency, 
and reduce emissions in milk and protein production.
Benefits of Animal Biotech
    Human Health

    Innovations in animal biotechnology can yield significant benefits 
to human and animal health, agriculture and food production, and the 
environment. Among these potential benefits is the ability to prevent, 
prepare for, and respond to outbreaks of infectious diseases such as 
coronavirus, Ebola, Zika, avian influenza (HPAI), and MERS, by creating 
more disease-resistant animals and providing disease treatments for 
humans.
    Genetically designed cattle are being developed to produce fully 
human polyclonal antibodies to provide treatments for infectious 
diseases such as COVID-19. Scientists create a cow embryo with parts of 
human chromosomes, including human antibody genes, and turn off the 
animal antibody genes. Once grown, researchers inject a non-infectious 
part of the novel coronavirus into the cow, which produces human 
antibodies to the virus. Scientists draw blood from the cows, extract 
and purify the antibodies with the hope that these antibodies may treat 
the coronavirus in humans.\40\
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    \40\ https://www.bio.org/blogs/can-cows-help-treat-covid-19.
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    Similarly, scientists have developed a chicken that is resistant to 
contracting and transmitting avian influenza.\41\ Other innovations in 
animal biotechnology may be able prevent, prepare for, and respond to 
outbreaks of infectious diseases by providing prevention strategies and 
treatments for humans. These breakthroughs are even more important 
given reports such as the swine flu strain with human pandemic 
potential increasingly found in pigs in China.\42\
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    \41\ https://www.fooddive.com/news/gene-edited-chicken-cells-may-
stop-the-spread-of-bird-flu/556976/.
    \42\ https://www.sciencemag.org/news/2020/06/swine-flu-strain-
human-pandemic-potential-increasingly-found-pigs-china.
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    Biotechnology can also strategically reduce and even eliminate the 
populations of insects that cause the greatest harm. Mosquitoes are not 
just a pest, but responsible for outbreaks of diseases like West Nile, 
Zika, and dengue. Genetically modified mosquitoes can be designed to 
help decrease and eventually diminish the overall population of 
mosquitoes. The U.S. Environmental Protection Agency (EPA) has granted 
permission to release these mosquitoes in parts of Florida and Texas. 
If the solution goes worldwide, we may be able to eradicate the number 
one killer of children in Africa, malaria.\43\
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    \43\ https://www.bio.org/blogs/its-one-health-oclock.

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    Animal Health

    It is not just diseases transmitted between animals and humans that 
can have devastating consequences for the economy. In 2015, the 
outbreak of avian influenza devastated poultry producers in Minnesota. 
The outbreak infected more than 100 farms in the state, forced the 
destruction of millions of birds, and cost the state economy nearly 
$650 million.\44\ Porcine Reproductive and Respiratory Syndrome (PRRS) 
is a disease that attacks the pigs' reproductive and respiratory 
systems, making it difficult for them to give birth and breathe. It can 
devastate an entire herd of 1,000 pigs in just 2 short months. African 
Swine Fever (ASF) has been devastating herds throughout Asia.\45\ 
Researchers at Iowa State University (ISU) estimate an outbreak in the 
U.S. could cost up to $50 billion.\46\ Gene editing can prevent these 
future outbreaks, as researchers are working to develop pigs with 
genetic resistance to PRRS,\47\ ASF,\48\ and Foot-and-Mouth Disease 
(FMD). These technologies can be used to make other animals resistant 
to disease, protecting farmers and the food supply.
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    \44\ https://www.mprnews.org/story/2017/03/08/bird-flu-outbreaks-
elsewhere-worry-minnesota-farmers.
    \45\ http://www.fao.org/ag/againfo/programmes/en/empres/ASF/
situation_update.html.
    \46\ https://www.card.iastate.edu/products/publications/synopsis/
?p=1300.
    \47\ https://innovature.com/article/agricultural-innovations-
protect-your-favorite-foods.
    \48\ https://innovature.com/article/gene-editing-could-protect-
pigs-diseases.

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    Sustainable Animal Production

    Precision breeding of animals to produce more meat or milk will 
allow for the reduction of the total number of animals in production, 
thus reducing the aggregate environmental impact. For example, even 
though there are fewer than half the dairy cows in the United States 
today as there were in 1950s, average milk production per cow has 
nearly doubled, largely because of genetic improvements through 
traditional breeding.\49\ While these improvements took over 60 years 
to accomplish, the use of technologies, such as gene editing, could 
allow us to make similar improvements in a fraction of the time.
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    \49\ https://www.wpr.org/how-we-produce-more-milk-fewer-cows.
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    The first bioengineered food animal approved to date, the 
AquAdvantage salmon, is a fish that can grow large and healthy with 
fewer resources, helping to reduce the environmental impact of raising 
fish. Through biotechnology the salmon grows to market-size using 25 
percent less feed than traditional Atlantic salmon on the market today. 
This makes an already efficient protein producer even better because it 
requires fewer wild fish to be converted into salmon feed. Further by 
being developed in domestic facilities close to major metropolitan 
areas, it significantly cuts transportation distance from farm to 
table. Unlike imported salmon, this salmon has a carbon footprint that 
is 23 to 25 times less than for traditional farmed salmon.\50\
---------------------------------------------------------------------------
    \50\ https://aquabounty.com/sustainable/.
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    Improvement of animal genetics will also be a critical aspect to 
helping livestock producers around the world adapt to climate change. 
Globally, but especially in tropical and subtropical environments, 
protecting herds from increasing temperatures expected with climate 
change will be very important.\51\ Research is currently being done to 
improve animal genetics, such as in cattle, to adapt to expected 
increasing temperatures.\52\ The UN FAO has also reported that 
improving fertility, use of genomics and genetic improvement can play a 
significant role in reducing emissions from the livestock sector.\53\
---------------------------------------------------------------------------
    \51\ https://www.bio.org/blogs/recombinetics-animal-gene-editing-
could-transform-beef-industry.
    \52\ https://futurism.com/scientists-want-to-genetically-engineer-
heat-resistant-cows-to-survive-climate-change.
    \53\ http://www.fao.org/3/a-i8098e.pdf.

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    Regulatory Impediments

    Unfortunately, the current regulatory approach to these 
technologies is an impediment to innovation and commercialization. The 
Food and Drug Administration (FDA) uses its ``new animal drug'' 
authority under the Food, Drug, and Cosmetics Act to assess animal 
biotechnologies. Evaluating food animals under this pharmaceutical-
based framework is essentially forcing a square peg in a round hole. 
Under this system, genetically engineered animals and their progeny 
could be considered ``drugs'' and farms and ranches could be regulated 
as ``drug manufacturing facilities.'' For developers, the FDA's current 
evaluation process is time-consuming, opaque, unpredictable, and 
disproportionate to the actual risk posed by the products being 
evaluated.
    FDA has announced that it plans to also regulate gene-edited 
animals under this system--even those products with edits that could 
have occurred naturally or through conventional breeding. This puts at 
risk an entirely new generation of technologies and threatens to drive 
research, jobs, and innovation overseas. Similar concerns were raised 
by a bipartisan group of Members in the House of Representatives in a 
letter to FDA last year.\54\
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    \54\ https://www.bio.org/sites/default/files/2020-05/190726%20-
%20EC%20Letter%20to%20
FDA%20re%20Gene%20Editing.pdf.
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    In more than 2 decades, the United States has approved only one 
biotechnology food animal for production and sale. Fast action is 
needed, or the U.S. will be prevented from deploying this promising 
technology and risk losing our leadership position in livestock 
genetics and in global meat and dairy production and export. We are 
already out of sync with the rest of the world, including European 
authorities (and livestock breeders), who are increasingly 
characterizing such approaches simply as advanced breeding. Other 
countries, like China, Canada, Australia, and Brazil, will be deploying 
this technology with or without the guidance of the United States. They 
will also begin to become more formidable exporters of their beef, 
pork, poultry, and fish products.\55\
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    \55\ https://thehill.com/opinion/energy-environment/373361-
regulatory-restructure-of-biotech-is-critical-to-the-future-of-us.
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    As USDA rightly note in its Task Force on Agriculture and Rural 
Prosperity, Federal regulations are limiting technological innovation 
in animal biotech.\56\ To overcome these regulatory barriers, BIO 
supports USDA's \57\ efforts to create joint agreement with FDA whereby 
the USDA leads regulatory oversight of biotechnology-derived food 
animals and the FDA leads oversight of non-food and biomedical animals. 
In addition, FDA should conduct a review of its process and implement 
specific process changes to improve its decisionmaking, transparency, 
and timelines for reviews. Developers and other stakeholders need 
confidence that FDA will be held accountable for approval timelines and 
ensure that the pathway to commercialization is predictable, clear, 
consistent, and based on risk.
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    \56\ https://www.usda.gov/sites/default/files/documents/rural-
prosperity-report.pdf.
    \57\ https://www.agri-pulse.com/articles/13210-perdue-says-mou-
with-fda-could-be-solution-to-animal-biotech-regulation.
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    Taking these steps will ensure America's farmers and ranchers have 
access to cutting-edge technologies to remain globally competitive and 
resilient to disease and climate change, the United States must have 
risk-proportionate regulations that spur biological innovations, while 
protecting health and environment.

    One Health

    In addition to technology, better coordination will ensure that our 
country is better prepared for the next pandemic. The One Health 
collaboration eliminates barriers that often exist between human 
health, animal health, and environmental health regulatory strategies 
to create smarter, multi-faceted and coordinated efforts. The 
bipartisan, Advancing Emergency Preparedness Through One Health Act of 
2019,\58\ (H.R. 3771/S. 1903) would direct the U.S. Department of 
Health and Human Services and USDA to coordinate with other agencies 
and state and local leaders to advance a national One Health \59\ 
framework to better prevent, prepare for, and respond to zoonotic 
disease outbreaks like COVID-19.
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    \58\ https://www.congress.gov/bill/116th-congress/house-bill/3771.
    \59\ https://archive.bio.org/sites/default/files/
OneHealth_Final.pdf.
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II. Sustainable Fuels
Benefits of Sustainable Fuels to Agriculture
    The development of sustainable fuels enables agriculture to be a 
key contributor in addressing emissions from the transportation sector, 
which is the leading source of greenhouse gas emissions according to 
the EPA.\60\ Not only is this one of the largest sectors of emissions, 
it is growing.
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    \60\ https://nepis.epa.gov/Exe/ZyPDF.cgi?Dockey=P100WUHR.pdf.

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    Emissions Reductions

    Biofuels and those produced using biological systems provide a 
strong and immediate solution to reducing emissions from all forms of 
transportation, including aviation, which has an immediate and long-
term nee for liquid fuels. Development of sustainable fuels allow 
agriculture to play a crucial role in addressing climate change. It is 
critical that we recognize that these are solutions that are available 
today, and do not require a mass turnover in vehicles. It is commonly 
known that carbon emissions act much like compounding interest. Just in 
the way that a dollar saved today is better than a dollar saved 
tomorrow, limiting carbon emissions today is far more valuable than 
limiting the same or a greater volume of emissions at a later date.\61\
---------------------------------------------------------------------------
    \61\ Frank, Jenny. ``Quantifying the Comparative Value of Carbon 
Abatement Scenarios Over Different Investment Timing Scenarios'' 
National Biodiesel Board Conference and Expo, 28 January 2020, Tampa, 
Florida. Next Generation Scientists for Biodiesel.
---------------------------------------------------------------------------
    Because of biotech innovations, the production of biofuels is 
becoming more efficient and environmentally sustainable. Biocatalysts, 
such as enzymes, lower energy requirements, increase reaction rates, 
can reduce the number of process steps necessary to make chemical 
transformations. Enzymes are selective, specific, and have a high 
catalytic rate; they are more efficient, producing chemical products 
with higher purity and fewer byproducts or wastes. Enzymes are enabling 
biofuel producers to convert corn stover, wheat straw, wood chips, 
sawdust, waste, and sugarcane bagasse into fuel, and to collectively 
increase biofuel yield and energy efficiency throughout the sector. 
Biocatalysts (e.g., bacteria) are enabling production of fuels and 
chemicals from new waste and residue streams. New bio-boosting 
chemicals are increasing biomass yields while eliminating the need for 
antibiotics in feed bioproducts for livestock. Companies have 
commercialized enzymes for producing cellulosic ethanol from 
agricultural waste and are currently operating cellulosic 
biorefineries.\62\
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    \62\ https://www.bio.org/industrial-biotechnology-unique-potential-
pollution-prevention.
---------------------------------------------------------------------------
    We are already reaping the benefits of the development of advanced 
and cellulosic biofuels. The use of low-carbon biofuels, primarily used 
in passenger cars, has resulted in significant greenhouse gas 
reductions, with cumulative CO2 savings of nearly 600 
million metric tons (mmt) since the RFS was enacted.\63\
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    \63\ https://ethanolrfa.org/wp-content/uploads/2019/02/
LCARFSGHGUpdatefinal.pdf.
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    The greenhouse gas emission reductions and benefits will only 
expand with the utilization of new conversion technologies and the 
development of advanced and cellulosic biofuels across all 
transportation sectors. As USDA highlighted last year, greenhouse gas 
emissions from corn-based ethanol are about 39 percent lower than 
gasoline. The study also states that when ethanol is refined at natural 
gas-powered refineries, the greenhouse gas emissions are even lower, 
around 43 percent below gasoline.\64\ Current Federal policy supporting 
these fuels, the RFS, requires lifecycle greenhouse gas reductions of 
at least 50 percent versus the relevant petroleum-based alternative for 
a fuel to qualify as an advanced biofuel, and at least 60 percent for 
cellulosic biofuels.
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    \64\ https://www.usda.gov/media/press-releases/2019/04/02/usda-
study-shows-significant-greenhouse-gas-benefits-ethanol.
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    Existing advanced and cellulosic biofuel technologies are far 
surpassing these requirements. As highlighted in an Environmental and 
Energy Study Institute (EESI) report, ``according to Argonne's GREET 
model, an energy crop like miscanthus can have negative greenhouse gas 
emissions, meaning that over the crop's life cycle, carbon 
sequestration outweighs emissions. Argonne researchers show that, 
compared to gasoline, biofuel from energy crops can reduce emissions by 
101 to 115 percent. Corn stover, a residue from corn, can reduce 
emissions by 90 to 103 percent.'' \65\ As the industry improves its 
efficiencies and practices, the greenhouse gas reductions of approved 
advanced and cellulosic biofuels are likely to be substantially 
greater. Further, new technologies such as gas fermentation, provide 
alternative routes to advanced biofuels, including sustainable aviation 
fuel (SAF), from a variety of biomass residues.
---------------------------------------------------------------------------
    \65\ https://www.eesi.org/articles/view/biofuels-versus-gasoline-
the-emissions-gap-iswidening#:
:targetText=Argonne%20researchers%20show%20that%20compared, 
for%20the%20RFS%20from
%202010.
---------------------------------------------------------------------------
    The development and expansion of algae and aquatic plant 
cultivation has great potential for the development of advanced 
biofuels. Microalgae are aquatic plants that can be induced to rapidly 
accumulate lipids, often greater than 60 percent of their biomass, 
while consuming large amounts of carbon dioxide. They can be cultivated 
using closed loop systems, open ponds, and photo-bioreactors, using 
less land, energy, and water than land crops. The characteristics of 
algae biofuels include high flash point, biodegradability, and low or 
no aromatic or sulfur compound, so they are being used to produce a 
variety of biofuels such as bioethanol, bio-butanol, jet fuel, 
biodiesel, bio gasoline, green diesels, and methane.\66\
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    \66\ https://farm-energy.extension.org/algae-for-biofuel-
production/.

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    Air Quality Benefits

    The environmental benefits of biofuels go beyond greenhouse gas 
reductions. The outbreak of COVID-19 has highlighted the importance of 
clean air to human health. Harvard University found that small 
increases in exposure to long-term levels of tiny particulate matter 
were linked to a big jump in the mortality rate for COVID-19. Each 
extra microgram of fine particulate matter per cubic meter that people 
were exposed to over the long-term was linked to an eight percent 
increase in the mortality rate.\67\ Similar results were found by the 
University of Cambridge which overlaid nitrogen dioxide 
(NO2) and nitrogen oxide (NO) levels from more than 120 
monitoring stations across England with figures on coronavirus 
infections and deaths. They found a link between poor air quality and 
the lethality of COVID-19 in those areas.\68\
---------------------------------------------------------------------------
    \67\ https://www.researchgate.net/publication/
340492612_Exposure_to_air_pollution_and_
COVID-19_mortality_in_the_United_States_A_nationwide_cross-
sectional_study.
    \68\ https://www.medrxiv.org/content/10.1101/2020.04.16.20067405v5.
---------------------------------------------------------------------------
    As BIO stated in its comments to the EPA Scientific Advisory Board 
(SAB) Review of COVID-19 Pandemic Scientific and Technical Issues to 
Inform EPA's Research Actives,\69\ ``our member companies offer several 
solutions that can not only help combat this pandemic, but also lessen 
the impact of a future pandemic by helping to establish a resilient, 
sustainable bioeconomy.''
---------------------------------------------------------------------------
    \69\ https://yosemite.epa.gov/sab/sabproduct.nsf//0/
2996BA363B41C2598525854C0048EA69?
OpenDocument.
---------------------------------------------------------------------------
    Harmful tailpipe emissions, including particulate matter (PM) from 
the transportation sector disproportionately affect areas comprised of 
minority populations. For example, according to a study by the Union of 
Concerned Scientists (UCS), African Americans and Latinos breathe in 
about 40 percent more particulate matter from cars, trucks, and buses 
than white Californians.\70\ Another UCS study found Northeast 
communities of color breath 66 percent more air pollution from 
vehicles.\71\
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    \70\ https://www.ucsusa.org/resources/inequitable-exposure-air-
pollution-vehicles-california-2019.
    \71\ https://www.ucsusa.org/about/news/communities-color-breathe-
66-more-air-pollution-vehicles.
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    According to the National Bureau of Economic Research, the United 
States saw fine particulate pollution increase 5.5 percent between 2016 
and 2018. According to the American Lung Association, State of the Air 
report for 2019, more than four in ten Americans live in counties that 
have unhealthy levels of ozone pollution or particular matter.\72\ 
Prior to COVID-19, the World Health Organization \73\ found that 4.2 
million deaths \74\ every year occur as a result of exposure to ambient 
air pollution. Since then, numerous studies have found that long-term 
exposure to levels of tiny particulate matter were linked to a 
significant increase in the mortality rate for COVID-19.\75\
---------------------------------------------------------------------------
    \72\ http://www.stateoftheair.org/key-findings/.
    \73\ https://www.who.int/health-topics/air-pollution#tab=tab_1.
    \74\ https://www.who.int/gho/phe/outdoor_air_pollution/burden/en/.
    \75\ https://www.newscientist.com/article/2241778-are-you-more-
likely-to-die-of-covid-19-if-you-live-in-a-polluted-area/.
---------------------------------------------------------------------------
    Sustainable fuels represent a readily available solution to 
addressing air quality by reducing tailpipe emissions including 
particulate emissions, hydrocarbons, and carbon monoxide, which helps 
prevent the formation of ground-level ozone. Data from 222 EPA sensing 
sites show that ozone levels have fallen during the period in which 
ethanol blending increased.\76\ Additional data from the University of 
Illinois-Chicago (UIC) show substantial reductions in particulate 
matter and benzene with the addition of biofuels.\77\ The American Lung 
Association, Upper Midwest Region found higher volumes of biofuels can 
reduce ozone-forming pollutants and evaporative emissions.\78\
---------------------------------------------------------------------------
    \76\ http://www.ethanolrfa.org/2014/12/real-world-ozone-and-
particulate-data-expose-fallacy-of-minnesota-study/.
    \77\ http://www.erc.uic.edu/assets/pdf/UIC_Cook_County_Slides.pdf.
    \78\ https://www.cleanairchoice.org/fuels/e85.cfm.
---------------------------------------------------------------------------
    Such benefits are not unique to ground transportation; research has 
demonstrated that SAF reduce contrails, particulate matter and mass 
emissions compared to conventional fossil jet fuels, with the potential 
to improve air quality near airports and reduce the climate impacts of 
aviation at high altitude.\79\ Additionally, sustainable fuels produced 
via microbial fermentation of industrial waste gases can limit the 
impacts of carbon pollution on human and environmental health locally. 
Sustainable fuels can be produced from the organic fraction of 
municipal solid waste (MSW), a much healthier option than MSW 
incineration which can contribute to air pollution.
---------------------------------------------------------------------------
    \79\ https://www.nature.com/articles/nature21420.
---------------------------------------------------------------------------
    As we begin to bring the economy back online, it is critical we do 
so with a cleaner, more resilient energy sector. Biofuels are an 
immediately available path toward decarbonizing the transportation 
sector and improving air quality while lowering fuel prices, driving 
economic growth, and creating jobs. However, this will require stable 
policies and regulations.
Stable Policies for Sustainable Fuels
    Renewable Fuel Standard

    When allowed to work, the RFS has enabled billions of dollars of 
investment in new technologies that have led to the rapid growth of the 
renewable fuels industry, the development of new fuel technologies, and 
the biobased economy. The growth of the biofuels industry has bolstered 
our rural communities and provided agriculture producers stable 
commodity markets, benefitting our nation's economic and energy 
security.
    Unfortunately, the demand destruction caused by the EPA's drastic 
expansion of small refinery exemption waivers or SREs has had a major 
impact on the industry, costing jobs, stifling investment in 
innovation, and undermining efforts to reduce greenhouse gas emissions 
in the transportation sector.
    In January 2020, the U.S. Court of Appeals for the Tenth Circuit 
ruled in Renewable Fuels Association v. EPA that EPA had exceeded its 
authority in granting SREs under the Renewable Fuel Standard to three 
refineries in 2016 and 2017, and that moving forward, EPA may only 
issue SREs to refineries that have continuously received exemptions for 
every compliance year since 2011.
    Despite this ruling, refiners have now filed at least 58 
retroactive SRE requests.\80\ This comes on top of another 27 SRE 
applications pending for 2019 and 2020. Unfortunately, rather than 
comply with the ruling in the 10th Circuit and immediately reject the 
retroactive requests it is perpetuating the uncertainty about the RFS 
by letting these pending applications linger.
---------------------------------------------------------------------------
    \80\ https://www.epa.gov/fuels-registration-reporting-and-
compliance-help/rfs-small-refinery-exemptions.
---------------------------------------------------------------------------
    Beyond SREs, innovative biofuel producers are also stymied by EPA's 
delays in the approval of new advanced and cellulosic biofuel pathways 
and petitions for production facilities. These delays are arbitrarily 
keeping advanced and cellulosic biofuels from reaching the marketplace, 
hindering the growth of the industry. EPA's failure to approve the 
registration for corn ethanol facilities that have registered for 
producing cellulosic biofuel from corn kernel fiber (CKF).
    As a result of the uncertainty of the RFS and the delays in new 
technologies coming to market, companies who have researched and 
developed technologies in the United States are looking to 
commercialize advanced and cellulosic biofuel technologies in countries 
like India and China which are investing heavily in biofuels to improve 
their air quality.
    BIO appreciates USDA's continued support of the biofuels industry. 
To ensure success of the sustainable fuels industry, enable agriculture 
to reduce emissions and bring even greater job growth to rural America, 
we urge the Department to push EPA to end its unwarranted expansion of 
SREs and move forward on stalled pathways and facility registrations.
    Further, we request the Department to encourage and support EPA to 
interpret the RFS broadly and accommodate all pathways and approve 
facility registrations that could fall within the existing statute. 
Specific areas that would have an impact immediately to accelerate the 
production of low carbon sustainable fuels are related to biological 
carbon capture and utilization (CCU), the interpretation and 
eligibility of ``renewable biomass'', the use of biointermediates, and 
life-cycle and tracking methodologies for sustainable fuels from waste 
agricultural residues such as CKF. This would have immediate benefits 
for the agricultural sector by create more demand for waste feedstocks 
and renewable biomass.

    Transition from a RFS to a Clean Fuel Standard

    As the Department explores options to harness the power of 
agriculture to decarbonize our transportation sector, we urge it to 
support new policies and programs that are technology and feedstock 
neutral and are based off of performance and their ability to deliver 
carbon reductions. Toward that end it will be critical for the 
Department to work with Congress in developing a Clean Fuel Standard 
(CFS) that builds on the success of the RFS and ensures agriculture and 
biofuels are part of the solution in reducing emissions.
    Given the success of the California model, other states \81\ and 
regions \82\ are beginning to consider establishing their own CFS 
programs to address emissions and air pollution. Not only does the 
establishment of these programs provide an additional value to 
biofuels, helping spur investment, production, and consumption of 
advanced biofuels, a national CFS would spur immediate, and additional 
carbon savings by allowing America's farmers to contribute by adopting 
practices that enhance soils natural ability to sequester carbon. When 
a CFS is coupled with a voluntary carbon crediting and verification 
program it would allow farmers to contribute quickly and effectively to 
fighting climate change.
---------------------------------------------------------------------------
    \81\ https://www.act-news.com/news/california-leads-with-low-
carbon-fuel-standard-programs/.
    \82\ http://blog.opisnet.com/rfs-lcfs.
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    Adoption of a CFS would not only incentive advanced biofuels like 
sustainable aviation fuel, but it would also incentivize fuels which 
have traditionally been left out of the RFS. Advanced technologies for 
the conversion of waste carbon oxides to sustainable aviation fuels and 
cellulosic diesels from woody residues that are poised for success 
today but have traditionally been left out of the RFS due to regulatory 
interpretations. A CFS that builds off the volumes and infrastructure 
put in place by the RFS is a simple, yet elegant way to steadily reduce 
emissions in transportation, allowing all forms of cleaner mobility to 
contribute, and bridge the divide between rural America and urban 
America.
III. Biobased Manufacturing
Support Farmers and Revitalize Manufacturing
    The expansion of biobased manufacturing can revolutionize industry 
by creating a sustainable value chain that use biological processes to 
convert renewable, low cost, or waste feedstocks into everyday 
products. It creates new markets for agricultural crops, crop residues 
and waste streams, as well as opportunities for innovation in producing 
consumer goods.
    These technologies represent novel, innovative ways to address 
plastic pollution and climate change. Already some 8 mmt of plastics 
enter our ocean on top of the estimated 150 mmt that currently 
circulate our marine environments.\83\ Through the application of 
biotechnology, we can create renewable chemicals, which can be used to 
produce sustainable plastics that are recyclable or biodegradable. 
While these materials are molecularly like their petrochemical 
equivalent, they reduce greenhouse gas emissions since they are 
produced from renewable or waste resources instead of oil and gas.
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    \83\ https://oceanconservancy.org/trash-free-seas/plastics-in-
theocean/#::text=Every%20year
%2C%208%20million%20metric,currently%20circulate%20our%20marine%20enviro
nments.
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    According to the U.S. Energy Information Administration, U.S. 
chemical production uses 28 percent of the total energy used by all 
industrial sectors.\84\ Without action, these emissions are expected to 
grow. In January, Louisiana regulators approved an air quality permit 
that will allow Sunshine Project, to pump 13.6 million tons of carbon 
dioxide into the atmosphere every year. That is equivalent to adding 
2.6 million cars to the road annually. In 2018, only 13 coal plants 
emitted more.\85\ A report in Environmental Research Letters identified 
88 petrochemical projects along the Gulf Coast that are either in the 
planning stage or under construction. If all are completed, their 
combined emissions output could reach 150.8 mmt, the equivalent of 38 
coal plants.86-87 
---------------------------------------------------------------------------
    \84\ https://www.eia.gov/energyexplained/use-of-energy/
industry.php.
    \85\ https://www.eenews.net/climatewire/stories/1062133995.
    \86\ Ibid.
    \87\ https://iopscience.iop.org/article/10.1088/1748-9326/ab5e6f/
pdf.
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    However, biobased products can provide a solution to the increasing 
rise in emissions in petrochemical plastic production. The USDA found 
that the development of renewable chemicals and biobased products 
removed 12.7 mmt of CO2 from the manufacturing sector in 
2016 alone in its report, An Economic Impact Analysis of the U.S. 
Biobased Products Industry.\88\ This is due to the displacement of 
petroleum and reduction of fossil fuels in the manufacturing and use of 
biobased products. The report goes on to note:
---------------------------------------------------------------------------
    \88\ https://www.biopreferred.gov/BPResources/files/
BiobasedProductsEconomicAnalysis
2018.pdf.

          The use of biobased products reduces the consumption of 
        petroleum equivalents by two primary mechanisms. First, 
        chemical feedstocks from biorefineries have replaced a 
        significant portion of the chemical feedstocks that 
        traditionally originate from crude oil refineries. 
        Biorefineries currently produce an estimated 150 million 
        gallons of raw materials per year that are used to manufacture 
        biobased products. Second, biobased materials are increasingly 
        being used as substitutes for petroleum-based materials, which 
        have been used extensively for many years. An example of this 
        petroleum displacement by a biobased material is the use of 
        natural fibers in packing and insulating materials as an 
        alternative to synthetic foams, such as Styrofoam. In this 
        report we updated the oil displacement values from the 2016 
        report to reflect economic growth. In 2016 the estimated oil 
        displacement is estimated to be as much as 9.4 million barrels 
---------------------------------------------------------------------------
        of oil equivalents.

    In addition to the environmental benefits, USDA found that the 
value added to the U.S. economy by biobased products was $459 billion 
in 2016. While employment in the industry increasing from 4.22 million 
jobs in 2014 to 4.65 million jobs in 2016.
    Even greater reductions of greenhouse gas emissions are possible 
through the expansion of biotechnology in manufacturing. World Wildlife 
Fund found ``if existing biotech solutions were used extensively in 
other traditional industries, such as detergent, textile, and pulp and 
paper manufacturing, another 52 mmt of greenhouse gas emissions 
reductions would be achieved annually.'' \89\
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    \89\ http://assets.panda.org/downloads/wwf_biotech.pdf.
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    Biotechnology is enabling the production of biobased plastics 
providing a sustainable alternative to petroleum-based plastics. More 
than half of all plastic ever created was produced in the last 15 
years, and right now, about 335 mmt of new, virgin plastic is created 
each year. Virtually all that new plastic will be made from oil and 
gas. Plastics now account for 3.8 percent of global greenhouse gas 
emissions and at the current rate willaccount for 15 percent of global 
emissions by 2050.\90\
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    \90\ https://www.nature.com/articles/s41558-019-0459-
z?utm_source=commission_junction&
utm_medium=affiliate.
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    Because some bioplastics are derived at least in part from corn, 
sugarcane, or other plants, they have a smaller carbon footprint, with 
lower cradle-to-plant-gate greenhouse gas emissions than their fossil 
fuel-based counterparts.\91\ Substituting the annual global demand for 
fossil-based polyethylene (PE) with biobased PE would save more than 42 
mmt of CO2. This equals the CO2 emissions of ten 
million flights aground the world per year.\92\ Replacing conventional 
1,4-Butanediol (BDO) with biobased BDO would save over 7 million tons 
of greenhouse gas emission per year, or the equivalent of taking 1.5 
million cars off the road.\93\ In addition to reducing greenhouse gas 
emissions, biobased BDO can produce compostable plastic packaging, 
reducing plastic waste.
---------------------------------------------------------------------------
    \91\ https://ihsmarkit.com/research-analysis/bioplastics-offer-a-
smaller-carbon-footprint.html.
    \92\ https://www.european-bioplastics.org/bioplastics/environment/.
    \93\ https://www.genomatica.com/wp-content/uploads/Genomatica-
Sustainability-and-Social-Responsibility-2019.pdf.
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    All biomanufacturing processes--whether enzymatic or microbial--
share the unique characteristic of avoiding use of toxic feedstocks and 
process reagents, which in turn minimizes toxic waste and byproducts. 
Manufacturers must manage byproducts of bioprocesses to prevent 
pollution.\94\ Just as enzymes improve biofuel production, 
manufacturers are using enzymes commercially to produce pharmaceuticals 
and other chemical compounds, food ingredients, detergents, personal 
care products, textiles, and paper products, avoiding use of toxic 
feedstocks and process reagents, which in turn minimize toxic waste and 
byproducts.\95\ By utilizing enzymes, textile mills used less energy 
and reduced their CO2 emissions by 12 mmt. This technology 
also has the added benefit of reducing the use of water in textile 
production by 8.1 billion cubic meters, equal to the annual consumption 
of 140 million households.\96\
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    \94\ http://www.bioprocessintl.com/manufacturing/facility-design-
engineering/minimizing-the-environmental-footprint-of-bioprocesses-
303905/.
    \95\ https://www.thebalance.com/enzyme-biotechnology-in-everyday-
life-375750.
    \96\ https://www.novozymes.com/en/news/news-archive/2019/05/
biological-solutions-on-the-catwalk-to-find-answers-for-sustainable-
fashion.
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    Sugar from crops like corn and wheat can be fermented using yeast 
to create renewable bio-succinic acid, which is commonly used as an 
emollient or fragrance carrier in various skin creams and lotions. 
Succinic acid is effective in combating acne and reducing skin 
flakiness and wrinkles. By using biotechnology, many personal care 
products can be made using a range of renewable, sustainable resources, 
including agricultural feedstocks. Carbon captured from industrial 
processes can be recycled and fermented using microbes to create 
renewable non-toxic isopropanol, a common alcohol used to extract and 
purify oils found in skin care products, such as acne treatments. Using 
synthetic biology, carbon-rich gases can be used to develop esters, a 
class of chemical compounds used to create certain aromas and 
fragrances in perfumes and cosmetics. By capturing and recycling these 
gases to be converted to esters instead of going into the atmosphere, 
environmental impact is reduced. Replacing petroleum-based butylene 
glycol with butylene glycol produced from a sustainable and renewable 
sugar fermentation process reduces greenhouse gas emissions by 51 
percent and allows consumers to avoid petroleum-based ingredients in 
their personal care products.\97\
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    \97\ https://www.genomatica.com/wp-content/uploads/SOFW-LCA-
Article.pdf.
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    Biotechnology can also improve the environmental footprint of 
textiles. Replacing petroleum based paraxylene with a bio-paraxylene 
produced from a mix of sugar cane and corn-based ethanol results in a 
70 percent reduction in carbon emissions. Bio-paraxylene can be used to 
produce a 100 percent bio-polyester. This can lead to a 25 percent to 
50 percent reduction in carbon emissions when compared to petroleum 
based polyester products. Further bio-polyester produced using bio-
paraxylene can be recycled in the same recycling infrastructure as 
petroleum-based polyester.\98\ Gas fermentation, which uses biology to 
convert waste industrial emissions to ethanol production, can produce 
textiles through conversion of this sustainable ethanol into 
fibers.\99\
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    \98\ https://www.virent.com/technology/sustainability/.
    \99\ https://www.lanzatech.com/2019/10/07/world-first-products-
made-from-recycled-pollution-reduce-emissions-and-keep-carbon-in-the-
ground/
---------------------------------------------------------------------------
    Traditional carpets take up the second-largest amount of U.S. 
landfill space. Approximately 3.5 billion pounds of carpet are put in 
U.S. landfills every year. Carpets are made up of a complex array of 
chemicals, either made of nylon, polyester, or polypropylene. 
Biotechnology can manipulate the polyester to form every element of the 
carpet, from base to tufts. The flooring, when discarded, can be 
returned to the manufacturer, ground up, and repurposed as another 
carpet, reducing the need for petroleum to manufacture new carpet.\100\ 
Biological gas fermentation combined with gasification, can convert 
mixed flooring wastes into the same chemicals used in carpet 
production.
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    \100\ https://www.fastcompany.com/3067849/the-first-100-recyclable-
carpets-are-here.
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Overcoming Regulatory Barriers
    These novel, innovative approaches to address domestic and global 
climate challenges are desperately needed. Just as it did with air 
pollution from transportation, COVID-19 has brough to light the impact 
petrochemical production has on human health, particularly on 
communities of color. This is exemplified in what has been called 
``Cancer Alley'' in Louisiana.\101\ As Beverly Wright, the founder and 
executive director of the Deep South Center for Environmental Justice 
in New Orleans stated in the New York Times April 29, 2020 article, `A 
Terrible Price': The Deadly Racial Disparities of [COVID]-19 in 
America, ``As soon as I heard about [COVID], I started getting nervous 
about the relationship between PM2.5 and this virus.''
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    \101\ https://www.businessinsider.com/louisiana-cancer-alley-
photos-oil-refineries-chemicals-pollution-2019-11.
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    Regulatory proposals to address plastic waste and pollution should 
set a performance standard that recognizes reductions in emissions in 
the production of chemicals and plastics. Further government efforts to 
promote and incentivize recyclability and reduce plastic waste should 
also seek to promote the use of bioplastics. Finally, the government 
should give broad regulatory acceptance of, and where applicable, 
regulatory preference for, innovative and sustainable biobased 
products.
    With these policies and principals we can achieve our goal of 
creating value added markets for commodities, rebuilding our national 
economy and workforce in a forward-looking, self-sufficient manner with 
the added benefit of addressing climate change and enhancing human 
health through improved air quality.
Provide Robust Funding of Public- and Private-Sector Scientific 
        Research
    The Federal Government's long history of generously funding 
research is an important foundation for the nation's bioeconomy and the 
development of the revolutionary technologies highlighted throughout 
BIO's comments. The successful adoption and deployment of 
biotechnologies in agriculture, renewable energy, and the bioeconomy 
have been enabled by USDA, the U.S. Department of Energy (DOE), and the 
Department of Defense (DOD), among other Federal agencies.
    As America's foreign competitors are investing greater amounts in 
research to lure the development of new technology offshore, these 
programs to support and incentivize foundational research and 
development activities are ever more critical to maintaining America's 
global preeminence in food, agriculture, bioenergy, and biobased 
manufacturing production. This investment also translates into 
opportunities for large private-sector investment in applied research 
and development.
I. Invest in Agricultural Research
Benefits of Research and Development
    Research has been central to the improvements in agricultural 
productivity. As the National Coalition for Food and Agricultural 
Research (NC-FAR) highlights, recent analysis by the International Food 
Policy Research Institute of 292 studies of the impacts of agricultural 
research and extension published since 1953 found an average annual 
rate of return on public investments in agricultural research and 
extension of 48 percent--an extremely high rate of return by any 
benchmark.\102\
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    \102\ https://www.ncfar.org/need.asp.
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    USDA Research, Education, and Economics (REE) programs have been 
critical to this success. USDA National Institute of Food and 
Agriculture (NIFA) and the Agriculture and Food Research Initiative 
(AFRI) have been essential for the foundational research and 
agricultural workforce development that complements and underpins large 
systems-level research, education, and extension activities. This core 
competitive grant program has been essential in establishing America 
the preeminent global leader in food, agricultural, and bioenergy 
production.
    USDA's Agricultural Research Service (ARS) plays a critical role in 
partnering with the university community and industry to advance 
science-based solutions. Research and Extension Programs such as 
McIntire-Stennis, 1890 Extension, Evans Allen, Hatch Act, and Smith-
Lever have been assisting farmers and ranchers in adopting best 
practices that increase productivity while improving soil, water, and 
air quality.
Provide Greater Investment in Research and Development
    Public and private investments in U.S. agricultural research and 
practical application have paid huge dividends to the United States. 
However, this unparalleled success story in the nation's food and 
agricultural system is in large part the product of past investments. 
Federal funding for food and agricultural science has been essentially 
flat for over 20 years despite much greater demonstrated needs and has 
reportedly declined by about 25 percent in real terms since 2003.\103\
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    \103\ https://www.ncfar.org/NCFAR_Testimony_FY_20_House_040519.pdf.
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    As researchers with ISU CARD pointed out in its report Measuring 
Public Agricultural Research and Extension and Estimating their Impacts 
on Agricultural Productivity: New Insights from U.S. Evidence \104\ 
with the world expected to reach 9.6 billion people--a 29 percent 
increase over 2013--by 2050, society must increase agricultural 
productivity without causing immense environmental damage and hunger. 
To achieve this will require greater investment in agricultural 
research and extension.
---------------------------------------------------------------------------
    \104\ https://lib.dr.iastate.edu/agpolicyreview/vol2016/iss1/3/.
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    The need to modernize our nation's aging food and agricultural 
science infrastructure, both at USDA labs and universities, is 
critical. Greater funding should be made to strengthen land-grant 
universities and HBCUs. Not only to bolster research for scientific 
agricultural advances, but to train the next generation of ag 
scientists and researchers and farmers and ranchers. Additional 
investments in research and education is also critical in assisting 
producers in increasing their use of precision agriculture, deployment 
of new crops, and sequestering more carbon in their soil.
    Programs such as USDA's Biotechnology Risk Assessment Research 
Grants Program (BRAG) supporting the generation of new information that 
will assist Federal regulatory agencies in making science-based 
decisions about the potential effects of introducing into the 
environment genetically engineered organisms, including plants, 
microorganisms--such as fungi, bacteria, and viruses--arthropods, fish, 
birds, mammals and other animals excluding humans. Continuation of 
programs like BRAG will be critical in supporting these technologies 
with advancing modern regulatory approaches need to advance innovation.
II. Sustainable Fuels
Benefits of Research and Development
    Bolstering funding of DOE, USDA, and other government research 
programs is necessary for the growth of the advanced biofuels industry. 
DOE's Office of Energy Efficiency and Renewable Energy (EERE) invests 
in clean energy technologies that strengthen the economy, protect the 
environment, and reduce dependence on foreign oil.
    According to DOE's Aggregate Economic Return on Investment in the 
U.S. DOE Office of Energy Efficiency and Renewable Energy,\105\ 
research and development (R&D) investments provide significant economic 
benefits. A total taxpayer investment of $12 billion (inflation-
adjusted 2015 dollars) in EERE's R&D portfolio has yielded more than 
$388 billion in net economic benefits to the United States.
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    \105\ Dowd, J. ``Aggregate Economic Return on Investment in the 
U.S. DOE Office of Energy Efficiency and Renewable Energy.'' (Oct. 
2017) Available at: https://www.energy.gov/sites/prod/files/2017/11/
f39/Aggregate%20ROI%20impact%20for%20EERE%20RD%20-%2010-31-17.pdf.
---------------------------------------------------------------------------
    The Bioenergy Technologies Office (BETO) within EERE funds vital 
research and development of technologies to convert our nation's 
biomass resources into clean, renewable fuels. BETO recognizes that 
biofuels are especially needed in the aviation industry, where liquid 
fuels are still the only viable fuel source for commercial airlines.
    USDA regional perspective has also been critical. Research through 
NIFA has helped support the development and production of advanced 
biofuels compatible with agricultural systems. It has brought together 
researchers, landowners, communities, and private industry to grow 
bioenergy and develop new biomass crops and supply chains.
    Federal Aviation Administration (FAA) programs are also critical to 
support the research and development, commercialization, and deployment 
of Sustainable Aviation Fuel. FAA's Office of Environment and Energy's 
R&D Program provides scientific understanding, development of new 
technologies, fuels and operations, and analyses to support achieving 
the Next Generation Air Transportation System (NextGen), and its goals 
of environmental protection that allow for sustained growth. The 
NextGen program is working with partners to develop solutions to reduce 
the impacts associated with aviation noise and exhaust emissions and 
increasing energy efficiency and availability. In alliance with 
research institutions and industry stakeholders, the program will 
accelerate the maturation of engine and airframe technologies to reduce 
aviation noise, fuel use, and emissions. FAA's Center of Excellence 
(COE) is charged with discovering, analyzing, and developing science-
based solutions to the energy and environmental challenges facing the 
aviation industry. Through COE, FAA has been supportive of alternative 
jet fuel testing and analysis efforts through the ASCENT. This program 
is working collaboratively with its 16 main universities and five 
affiliate universities.
    These programs have been vital to research and development and 
growth of the advanced and cellulosic biofuels sector.
Greater Investments in Research and Development
    As the government seeks to reduce emissions throughout the economy 
its critical for the Federal Government to recognize that liquid fuels 
will remain the main source of energy for transportation and to 
continue to invest in research and development of technologies to 
convert biomass and waste feedstocks into clean renewable fuels.
    Research and development in sustainable fuels should also remain 
feedstock neutral. To advance the next generation of biofuels, DOE 
should also support policy, research, and infrastructure directed to 
the use of using corn cobs, stover, and corn kernel fiber as a fuel to 
generate steam and electricity and as a source of cellulosic feedstock 
for ethanol.
III. Biobased Manufacturing
Benefits of Research and Development
    Research supported by USDA ARS has been critical in finding new 
uses of agricultural commodities and by products. Research related to 
biobased products focuses on developing technologies leading to new and 
improved non-food products that expand markets for farm products, 
replace imports and petroleum-based products, and offer opportunity to 
meet environmental needs. Research also addresses the development of 
appropriate feedstocks for biobased products.
    DOE EERE programs including BETO and the Advanced Manufacturing 
Office (AMO) have been essential in supporting, developing, and 
deploying new, novel technologies that help domestic manufacturing 
become more sustainable resilient, adaptable, and globally competitive.
    Globally, there is a strong push to decarbonize fuels and materials 
from wastes and residues. Conversion technologies are being developed 
in Europe and Asia, where there is both supportive policies and 
significant investment in research, development, and demonstration 
projects. Technologies that have been developed in the U.S. are often 
initially commercialized elsewhere. We urge the Department to consider 
support for pilot and demonstration scale projects in the U.S., and, 
where appropriate, provide funding to support U.S. industry 
partnerships with international collaborators to speed the rate of 
deploying U.S. based technologies at home and abroad.
Greater Investments in Research and Development
    As USDA highlighted in its 2018 report An Economic Impact Analysis 
of the U.S. Biobased Products Industry many countries world-wide are 
investing in these technologies, and the U.S. should do so as well. 
Research is critical to spurring innovation and increasing the variety 
and efficacy of biobased products and fully utilizing biobased 
feedstocks. Many of the biobased innovation available today began in 
university laboratories. Supporting the source of these important 
developments will be vital to enhancing the growth of the industry. The 
government should increase opportunities for private sector and 
university collaboration through ongoing National Science Foundation 
(NSF), USDA, and DOE funding grants.\106\
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    \106\ https://www.biopreferred.gov/BPResources/files/
BiobasedProductsEconomicAnalysis
2018.pdf.
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    Also critical to the development of the biobased economy is 
determining its value and identifying the segments which need 
investment and research and development. Key to this is updating the 
North American Industry Classification System (NAICS) codes. BIO 
supported language in the 2018 Farm Bill.\107\ BIO applauds USDA's 
comments to the 2017 NAICS Updates for 2022 to establish a measurement 
for biobased products.\108\
---------------------------------------------------------------------------
    \107\ https://republicans-agriculture.house.gov/uploadedfiles/
greenwood_testimony.pdf
    \108\ https://www.regulations.gov/document?D=USBC-2020-0004-0046.
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    Funding of base biological and environmental research also has 
broad implication in environmental remediation, and reengineering of 
microorganisms and plants with direct relevance to energy, climate, and 
the environment and enhancing the sustainability of biobased products 
and renewable fuels.
    Support of land-grants and HBCUs will also be critical for STEM 
education so that as the bioeconomy grows, we have a domestic workforce 
that can take advantage of the increasing number of high-paying 
scientific jobs.
IV. Investing in Platform Technologies
    To achieve the goals set out in the AIA and meet the challenge of 
feeding a growing world and tackling climate change will require 
significant investments in platform technologies such as gene editing 
and synthetic biology.
    Investments in next generation biotechnologies and genomics also 
have great potential to meet this challenge and achieve the Departments 
goals set forth in the AIA. Gene editing for multi-trait seed 
improvements can enable agriculture to increase production by up to 400 
mmt, reduce emissions by up to 30 megatonnes of CO2, reduce 
freshwater withdrawals by up to 180 billion cubic meters, reduce the 
number of micronutrient deficient by up to $100 million, while 
generating up to $100 billion in additional farmer income.\109\
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    \109\ https://www.ncfar.org/HSS_20200713_Presentation.pdf.
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    As highlighted earlier, advancements in animal biotechnology can 
further our nation's efforts to safeguard animal health, food safety, 
and the environment. Increasing genomic research in animal agriculture 
will also unleash enormous progress in terms of food production and 
security.
    Just like animal biotech, research and development of plant protein 
and cellular agriculture can provide solutions for improving the 
productivity and environmental sustainability of food, feed, and animal 
production and addressing the increasing demand for protein in a 
growing world. These technologies have tremendous potential for 
expanding our nation's bioeconomy and diversifying our food supply to 
adapt and mitigate disease and environment. Supportive research by USDA 
AFRI can help advance the development and optimization of cell lines, 
cell culture media, scaffolding, and cultivators (bioreactors) for 
producing meat through cellular agriculture.
    Increasing research in synthetic biology will unlock innovations in 
agriculture and food productions, energy, and manufacturing. 
Biotechnology companies have identified opportunities to incorporate 
synthetic biology \110\ in groundbreaking advances in industrial 
biotechnology manufacturing processes. Companies have begun using 
science to optimize the processes for producing renewable chemicals, 
biobased products, and biofuels. With synthetic biology techniques, 
industrial biotechnology companies can save time by shortening the 
number of steps used in traditional processes, reducing costs while 
developing new products. They can also reduce the products' impact on 
the environment. With proper support synthetic biology can transform 
our economy.
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    \110\ https://www.bio.org/blogs/synthetic-biology-innovation-
industrial-biotechnology.
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    Because of strong Federal support, the United States is a leading 
nation in the development of synthetic biology. This success and high 
research productivity are not lost on foreign governments, including 
China, who are trying to kick-start their biomanufacturing sectors to 
catch up to, or even leapfrog, the U.S. Our continued growth will be 
fueled by robust scientific research, strong intellectual property 
rights, well-functioning technology transfer, dynamic capital 
investment, science- and risk-based regulation that minimizes 
obstacles, and public support that embraces the positive influence of 
biotechnology.
    Supportive grants for research and development and startup will 
provide significant advances in foundational tool development and 
practical applications ranging from bioenergy, biomanufacturing, to 
biomedicine. The recommendations put forward by the National Academies 
of Sciences Engineering Medicine report, Safeguarding the Bioeconomy 
\111\ can give further guidance in advancing the bioeconomy for the 
betterment of the U.S. and society.
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    \111\ https://www.nap.edu/resource/25525/interactive/.
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    BIO has also supported S. 3734, the Bioeconomy Research and 
Development Act \112\ to strengthen and broaden engineering biology by 
establishing an initiative to advance research and development, advance 
biomanufacturing, and develop the future bioeconomy workforce. The 
legislation would also establish a committee to coordinate research in 
engineering biology across the Federal agencies.
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    \112\ https://www.congress.gov/bill/116th-congress/senate-bill/
3734.
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    DOD's Synbio Manufacturing MII initiative also has great potential 
for collaborative, pro-innovation opportunities to expand American 
leadership in biotechnology.
Modernize Infrastructure
    Growing a resilient bioeconomy of the future will also require 
important investments in infrastructure, such as increased, widespread 
access to broadband internet technology, pipelines, construction of 
bioreactors and biobased manufacturing facilities, and distribution 
capacity for carbon dioxide and sustainable fuels. It will also require 
the government working with financial institutions and investors to 
promote access to capital for startups in the biobased manufacturing 
sectors across food, material products, and energy.
    COVID-19 showed the vulnerabilities in our supply chain. To 
mitigate the effect climate change will have on it in the future, it is 
critical we develop a cleaner, more resilient agricultural, energy, and 
manufacturing infrastructure.
I. Access to Broadband
    COVID-19 has highlighted the importance of broadband to the modern 
economy and the digital divide rural communities are facing. The 
Federal Communications Commission \113\ estimated in 2017 that it would 
cost $80 billion to bring high-speed internet to remaining parts of the 
country that do not have access, while a more recent U.S. Department of 
Agriculture \114\ report estimated it would require between $130 and 
$150 billion over the next 5 to 7 years, to adequately support rural 
coverage and 5G wireless densification.
---------------------------------------------------------------------------
    \113\ https://transition.fcc.gov/Daily_Releases/Daily_Business/
2017/db0119/DOC-343135
A1.pdf.
    \114\ https://www.usda.gov/sites/default/files/documents/case-for-
rural-broadband.pdf.
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    Despite this cost, bringing high-speed internet infrastructure to 
rural areas is essential to building a bioeconomy. Farmers and ranchers 
who participate in carbon markets will need reliable internet access to 
transmit the data that emissions reductions from soil carbon 
sequestration are real and verifiable. Reliable access to the internet 
is also critical to the deployment of next generation precision 
agriculture technologies which will be essential to sustainably 
increasing production.
    The internet is also critical to ensuring biobased manufacturers 
and biofuel producers can remain economically competitive
II. Grants and Loan Guarantees for biorefineries.
    USDA has been a critical partner in supporting and providing 
financial support to the development of advanced biofuels and renewable 
chemicals.
    The Biorefinery Assistance Program loan guarantee program provides 
manufacturers access to capital for large-scale projects in rural 
communities. Without the loan guarantee program, new innovative 
companies might never be able to pool sufficient capital to commence 
development of a project in rural communities with a small population. 
These biorefineries are proven drivers of job and economic growth for 
rural communities.
    The 2018 Farm Bill expanded access to this program to renewable 
chemical and biobased product manufacturers; however, it only provided 
mandatory funding to the program through Fiscal Year 2020. To spur 
growth of additional biorefineries in rural communities, USDA should 
provide loan guarantees to new projects from the funding already 
allocated to this program. Additional funding should be provided in 
future years to support the construction of additional biorefineries.
III. Investments in Biofuels Infrastructure
Pumps and Pipelines
    USDA has been a great champion in promoting the development of 
infrastructure needed to expand the marketplace to supply more 
renewable fuel to America's drivers through the Biofuel Infrastructure 
Partnership (BIP) and the proposed Higher Blends Infrastructure Program 
(HBIIP).
    In addition to funding the installation and conversion of pump 
infrastructure, the government should also make investments in 
pipelines and terminals to deliver greater volumes of sustainable fuels 
as well as distribute CO2 developed from biofuels. Having 
greater distribution capacity can help avoid the supply disruption the 
food industry faced due to COVID-19 when the closure of ethanol 
facilities led to a CO2 crunch.
Sustainable Aviation Fuels
    The development of sustainable aviation fuels also represents a 
growing opportunity for the development of biofuels producers and 
biomass producers. To support that effort investments should be made in 
infrastructure to incentivize the creation and use of sustainable 
aviation fuels in commercial aviation to reduce fuel costs, pollution, 
and the overall environmental footprint of U.S. aviation.
USDA Collaboration
    In 2016, the U.S. Navy Great Green Fleet demonstrated the potential 
of advanced biofuels in reducing emissions in maritime engines. Named 
to honor President Theodore Roosevelt's Great White Fleet, the year-
long initiative in the John C. Stennis Strike Group (JCSSG) used 
alternative fuel sources, energy conservation measures, and operational 
procedures to reduce its fuel consumption. The fleet used biofuels made 
from ten percent beef tallow provided from farmers in the Midwest and 
90 percent marine diesel, and it was cost competitive with traditional 
fuels. It is used as a drop-in alternative, meaning no modifications to 
engines or operational procedures are required.\115\
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    \115\ https://www.navy.mil/submit/display.asp?story_id=95398.
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    The Great Green Fleet was the result of the DOD, USDA, and DOE, 
providing funding under the Defense Production Act toward the 
construction of biorefineries that produce cost-competitive, drop-in 
military biofuels.\116\ As a result, these refineries are now coming 
online, capable of producing fuels for the military and aviation 
sector.
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    \116\ http://www.biofuelsdigest.com/bdigest/2014/09/19/breaking-
news-us-navy-doe-usda-award-210m-for-3-biorefineries-and-mil-spec-
fuels/.
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    The military is the nation's largest single consumer of fuel, so 
the Navy's purchase of 450,000 gallons of biofuel for the exercise 
signaled a potentially huge defense market for liquid renewables. 
However, when the program essentially ended in 2017, along with the 
Navy's issuance of short-term contracts, it left investors wary of 
financing biofuel refineries.
    Given the size of the military's fuel demand issuing a requirement 
for Federal agencies to use a certain volume of biofuels could spur 
long-term investment \117\ in the development of sustainable fuel 
facilities.
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    \117\ https://www.bloomberg.com/news/articles/2020-07-09/biofuel-
revolution-was-doomed-by-policy-and-investment-failures.
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IV. Tax Incentives
    The biobased economy and industrial biotechnology contribute 
greatly to the U.S. economy. Enacting sustained, supportive tax policy 
will lead to even greater growth domestically in this industry. 
Targeted tax policies will enable emerging technologies in advanced 
biofuels, renewable chemicals, and biobased products to overcome the 
challenging capital environment for first-of-a-kind biorefinery 
construction and allow them to bring their technologies to commercial 
deployment. This will unleash our members' scientific innovation 
potential and grow the bioeconomy.
Biofuels
    Biofuel tax provisions supporting the development of advanced and 
cellulosic biofuels--particularly the Second Generation Biofuel 
Producer Tax Credit (PTC), the Special Depreciation Allowance for 
Second Generation Biofuel Plant Property, the Biodiesel and Renewable 
Diesel Fuels Credit, and the Alternative Fuel Vehicle Refueling 
Property Credit--are incredibly important to our companies that are 
making significant investments to create new agricultural supply 
chains, build infrastructure for liquid biofuels, and develop 
innovative new technologies. These credits have enabled our industry to 
create new jobs, contribute to rural prosperity, and diversify our 
nation's energy supply. For example, the biodiesel tax credit has 
supported the production of biofuels used in aviation.\118\
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    \118\ https://www.nata.aero/assets/Site_18/files/GIA/121SMS/
Aviation%20Industry%20Co
alition%20Support%20for%20Biodiesel%20credit%20extension%20Neal%20Brady.
pdf.
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    The expiration and continued on-again off-again nature of these 
incentives has created uncertainty for investors and the industry about 
the availability of these credits, jeopardizing the long-term 
investments necessary for the development of biofuels. While these tax 
incentives enjoy broad \119\ bipartisan 120-121   support 
\122\ for these tax incentives their short-term availability makes it 
difficult for companies to make long-term planning decisions. Ensuring 
the growth of advanced and cellulosic biofuels industry will require 
long-term tax incentives to avoid creating uncertainty for investors 
and companies trying to raise capital.
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    \119\ https://finkenauer.house.gov/sites/finkenauer.house.gov/
files/documents/Second%20Gen
%20Biofuels%20Extender%20Support.pdf.
    \120\ https://www.biotech-now.org/wp-content/uploads/2019/11/
Second-Gen-Biofuels-Letter-11-26-
18.pdf?_ga=2.27182452.850446835.1573066958-1287514846.1535039721.
    \121\ http://kce.informz.net/KCE/data/images/
Final%20Signed%20Feb%202019%20Loebsack
%20LaHood%20Biodiesel%20Letter.pdf.
    \122\ https://finkenauer.house.gov/sites/finkenauer.house.gov/
files/3435_001.pdf.
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    The development of a long-term SAF specific blender's tax credit 
\123\ could attract significant investment to the sector and address 
existing structural and policy disincentives that have prevented the 
aviation biofuels industry from taking off.
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    \123\ https://www.bio.org/letters-testimony-comments/sustainable-
aviation-fuels-saf-tax-incentive-letter-congress.
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Renewable Chemicals
    To realize the full potential of the domestic renewable chemicals 
industry, existing renewable energy, manufacturing, or environmental 
tax incentive regimes should be opened to renewable chemicals. 
Providing a Federal income tax credit for domestically produced 
renewable chemicals, could create domestic jobs and other economic 
activity that can help secure America's leadership in the important 
arena of green chemistry. Like current law for renewable electricity 
production credits, the credits would be general business credits 
available for a limited period per facility.
Carbon Capture and Utilization
    Maintaining and extending the 45Q tax credits for CCUS will help 
drive investment and development of innovative new technologies which 
can capture carbon. The credit monetizes carbon to produce valuable 
products. Capturing waste carbon from power plants and manufacturing 
facilities can be converted into valuable products such as advanced 
biofuels, animal feed, and chemicals. As a result, CCUS helps displace 
petroleum and other carbon feedstocks. Already, integrating CCUS with 
biofuels projects is producing negative emissions fuels.\124\
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    \124\ https://www.gasworld.com/velocys-signs-ccus-agreement-with-
oxy/2017915.article.
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Opportunity Zones
    The Opportunity Zone (OZ) tax incentive has spurred investment in 
under-capitalized communities. Any corporation or individual with 
capital gains can qualify. However, the OZ guidance is unclear to 
investors and developers if biobased technologies can qualify for OZ 
tax incentivizes. A relatively minor clarification to OZ Guidance could 
potentially unlock billions of development dollars for bioeconomy 
manufacturing facilities.
V. Bolstering the Supply Chain
    Biobased manufacturing can be a solution to making sure those on 
the ground fighting the pandemic have the protection they need. Demand 
for personal protective equipment (PPE) is currently outpacing supply. 
To ensure that we can adequately fight the virus, it is critical that 
doctors, nurses, first responders, and scientists developing potential 
cures have access to PPE.
    Increasing production of renewable chemicals made from innovative 
biotechnologies and synthetic biology will help us meet the growing 
demand of PPE. Development of PPE and other products from biobased 
materials can also help address the increase in waste from disposable 
masks and other PPE which is posing new problems for the Earth's 
oceans.\125\ One study estimated if every person in the United Kingdom 
used a single-use face mask a day for a year it would create an 
additional 66,000 metric tons of contaminated waste and 57,000 metric 
tons of plastic packaging.\126\ Since these products can be 
biodegradable or recyclable, they can significantly reduce the amount 
of waste. It will also increase the demand for biomass feedstocks as 
producers are faced with a downturn in commodity prices.
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    \125\ https://www.fastcompany.com/90520661/masks-gloves-and-other-
coronavirus-waste-are-starting-to-fill-up-our-oceans?.
    \126\ https://www.greenbiz.com/article/how-face-masks-gloves-and-
other-coronavirus-waste-are-polluting-ocean.
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    In addition to PPE, biobased products can help meet the growing 
need for testing products to track the virus and research cures. It can 
also help us meet the demand for sterilizing and cleaning products. In 
addition to ethanol producers, biotech companies are developing key 
ingredients that can help in the production of hand sanitizers. Green 
surface cleaners can meet the growing demand to sterilize surfaces in 
hospitals, public places, and homes. While enzyme developers are 
enhancing detergents that can increase cleaning efficacy even in low 
temperature washing, circumventing the need for hot water and reducing 
the environmental footprint of the sterilization process.
    To meet this demand, the Department and the Administration need to 
make greater investments in research, development, and deployment of 
biobased products to tackle COVID-19. We would encourage USDA to use 
whatever authorities it has to bolster the biobased sector, including 
expedited distribution of loans under the Biorefinery, Renewable 
Chemical, and Biobased Product Manufacturing Assistance Program to 
build expedited capacity for biorefineries producing renewable 
chemicals, increasing promotion of the benefits biobased products can 
provide in addressing the COVID-19 under the BioPreferred Program and 
ensuring Federal agencies are adhering to the program's procurement 
requirements.
Incentivize Farmers
I. Carbon Sequestration
    To increase agricultural production while reducing the 
environmental impacts and emissions from production will require 
incentivizes throughout the entire value chain, especially at the farm 
level.
    Promoting greater utilization of crops and practices that impart 
more carbon into the soil and out of the atmosphere through their roots 
will be critical to keeping warming below 2 C. This can be 
accomplished through simple, low-cost incentives to farmers for 
capturing carbon. The FAO noted that soils can sequester approximately 
20 petagrams of carbon in 25 years, that's more than ten percent of 
anthropogenic emissions.\127\ The United States Mid-Century Strategy 
for Deep Decarbonization estimated that U.S. lands have been a net 
``carbon sink'' for the last 3 decades and through enhancement they 
could offset up to 45 percent of economy wide emissions by 2050.
---------------------------------------------------------------------------
    \127\ http://www.fao.org/fileadmin/user_upload/soils-2015/docs/
Fact_sheets/En_IYS_ClCng_
Print.pdf.
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    What is needed from government is the establishment of 
infrastructure to measure and verify those carbon sequestrations at the 
local farm level. Furthermore, farmers need assistance in understanding 
and accessing the current voluntary and compliance markets for these 
credits. Common sense policy will make sure that America agriculture 
continues to lead on this new frontier of climate change mitigation and 
restoration.
    Toward this end, BIO is supportive \128\ of the Growing Climate 
Solutions Act \129\ (GCSA) (S. 3894/H.R. 7393) introduced by Senators 
Mike Braun (R-IN) and Debbie Stabenow (D-MI) and Representatives 
Abigail Spanberger (D-VA) and Don Bacon (R-NE) This bill will support 
America's farmers, ranchers, and foresters who want to adopt innovative 
practices that combat climate change, while continuing to provide the 
world with food, feed, and fiber.
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    \128\ https://www.bio.org/press-release/bio-supports-growing-
climate-solutions-act.
    \129\ https://www.congress.gov/bill/116th-congress/senate-bill/
3894.
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II. Incentivizing New Technologies
    GCSA or other carbon markets can foster acceptance for new 
technologies that can further reduce the environmental impact of 
agriculture, including tools like precision plant breeding, 
biostimulants, and microbial inoculants and enhancing animal feed with 
enzymes and other additives to reduce emissions in livestock. These 
improved agricultural practices increase crop yields and provide 
several environmental benefits including capturing nitrogen directly 
from the atmosphere and increasing root growth that binds carbon to the 
soil.
    Combined with modern agricultural techniques and sustainable 
farming practices such as planting cover crops and no-till, these 
innovative technologies that enhance productivity can play a key role 
in sequestering carbon dioxide in the soil, improving soil health, and 
protecting America's waterways.
    To further encourage the use of these technologies additional 
incentivizes could be created. The Section 45Q provides a performance-
based tax credit to power plants and industrial facilities that 
capture, store, and/or utilize carbon oxides that would otherwise be 
emitted into the atmosphere as CO2. Expanding the credit to 
new technologies that are being developed to amplify soil carbon 
sequestration through forestry and crops would incentivize producers to 
utilize this technology reducing atmospheric carbon.
Build Public Support and Increase Market Access for Innovative 
        Technologies
I. Build Public Support and Market Access
Growing Trust in Innovation
    Innovation flourishes when science and consumer values are aligned 
and complement one another. The U.S. government's regulatory approach 
toward innovative products should be supported by credible transparency 
measures. A proactive approach to transparency stands to build trust 
with the broader agri-food ecosystem.
    During the public comment period on the SECURE Rule,\130\ BIO 
advocated \131\ for a process to improve public access to information 
about new agricultural biotechnology products. While the final rule 
does not contain a mechanism for mandatory notification, BIO encourages 
increased openness about products entering the marketplace and best 
practices developers use in advancing beneficial products to the 
commercial marketplace.
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    \130\ https://www.bio.org/letters-testimony-comments/bio-comments-
usdas-proposed-part-340-revisions.
    \131\ https://www.bio.org/letters-testimony-comments/bio-submits-
letter-office-management-and-budget-part-340.
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    BIO is advocating that the U.S. government play a role in driving 
an inclusive and impactful approach to transparency. We encourage 
agencies to ensure that regulatory policies are durable and legally 
defensible. Further, we encourage agencies to articulate to the public 
the rationale for their approach, including safety assessments.
    The U.S. Government should establish a biotechnology clearinghouse 
that is geared toward consumers and builds off the Food and Drug 
Administration's Agricultural Biotechnology Education and Outreach 
Initiative.\132\ This clearinghouse should provide information about 
common uses of biotechnology, like gene editing, and the safety of 
innovations commonly used in the food and agricultural system.
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    \132\ https://www.fda.gov/food/agricultural-biotechnology/
agricultural-biotechnology-education-and-outreach-initiative.
---------------------------------------------------------------------------
    We look forward to working with agency experts to evaluate 
mechanisms to affirm and communicate the safety and benefits of 
biotechnology.
    To learn more please visit BIO's Growing Trust in Innovation 
webpage: https://www.bio.org/growing-trust-innovation.
BioPreferred
    Managed by USDA, the goal of the BioPreferred program is to 
increase the purchase and use of biobased products from agricultural 
feedstocks. The BioPreferred Program was created by the 2002 Farm Bill 
and reauthorized and expanded in the 2018 Farm Bill. The program's 
purpose is to spur economic development, create new jobs and provide 
new markets for farm commodities. The increased development, purchase, 
and use of biobased products reduces our nation's reliance on 
petroleum, increases the use of renewable agricultural resources, and 
mitigates adverse environmental and health impacts.\133\ Prior to the 
2018 Farm Bill, due to limitations in verification methodology, the 
BioPreferred program only incentivized procurement of plant-based 
products. The 2018 Farm Bill requests USDA to develop verification 
methods for products made from biological CCU. This will expand 
opportunities for biobased products made from waste resources.
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    \133\ https://www.biopreferred.gov/BioPreferred/faces/pages/
AboutBioPreferred.xhtml.
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    The BioPreferred Program is transforming the marketplace for 
biobased products through two initiatives: purchasing requirements for 
Federal agencies and their contractors; and voluntary product 
certification and labeling. As highlighted above, the label is helping 
drive consumer recognition of biobased products that are displacing 
about 300 million gallons of petroleum per year--the equivalent to 
taking 200,000 cars off the road.\134\ However, while Federal law, the 
Federal Acquisition Regulation, and Presidential Executive Orders 
direct all Federal agencies and their contractors to purchase biobased 
products in categories identified by USDA through the BioPreferred 
Program,\135\ oftentimes Federal agencies fail to give preference to 
biobased products. To ensure the BioPreferred Program drives growth of 
the bioeconomy, the Administration should ensure Federal agencies 
follow through with the requirements to give preference to biobased 
products and identify noncompliance.
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    \134\ https://www.usda.gov/media/press-releases/2016/10/03/usda-
report-shows-growing-biobased-products-industry-contributes.
    \135\ https://www.gsa.gov/governmentwide-initiatives/
sustainability/buy-green-products-services-and-vehicles/buy-green-
products/biobased-and-biopreferred-products.
---------------------------------------------------------------------------
    The following recommendations put forward in An Economic Impact 
Analysis of the U.S. Biobased Products Industry \136\ can make this 
achievable:
---------------------------------------------------------------------------
    \136\ https://www.biopreferred.gov/BPResources/files/
BiobasedProductsEconomicAnalysis
2018.pdf.

   Improve the ability of the Federal Government, including the 
        General Services Administration and other acquisition 
        departments of Federal agencies, to track the purchase of 
        biobased products in acquisition systems. Currently, there is 
        not a singular way of doing so, and it is difficult to 
        accurately determine the increases in the use of biobased 
---------------------------------------------------------------------------
        products by the Federal Government.

   Expand marketing and consumer education of the BioPreferred 
        Program's USDA Certified Biobased Product label. Currently, 
        many consumers are confused or are unaware of what a biobased 
        product is, and they do not recognize or understand the label. 
        While there are certainly benefits to having products labelled 
        as USDA Certified Biobased, increased market recognition would 
        help the biobased products industry grow and encourage more 
        companies to pursue certification.

   Leverage the similar goals between the USDA and the DOE to 
        cooperate on increasing the purchase of biobased products. Both 
        agencies have similar objectives in terms of growth and less 
        reliance on nonrenewable resources, and research supported by 
        both agencies can provide greater power and increased success.
Demonstrate Sustainability
    Developing carbon markets are not only beneficial to incentivizing 
producers to sequester carbon in the soil, but can bring greater value 
to sustainable fuels, biobased products, and food and feed 
applications. These markets allow the manufacturers of biobased 
chemicals, plastics, food, animal feed, and everyday materials to 
reliably demonstrate their true environmental benefit, from farm to 
consumer.
    Additional mechanisms should be developed to better enable 
producers to showcase the benefits of these technologies.
Trade
    An effective U.S. Government trade policy is critically necessary 
to address tariff and nontariff barriers that affect the trade of, and 
innovation in, biotech products globally. In particular, the U.S. 
bioeconomy needs a proactive trade agenda focused on enhancing IP 
protection abroad, a harmonized and science-based regulatory 
environment, fair and equitable technology transfer policies, and 
access and enforcement policies that appropriately value American 
innovation and are governed by the rule of law. We applaud that the 
United States is actively negotiating agreements with key trading 
partners such as China to address systemic trade practices such as 
forced technology transfer and IP theft that threatens biotechnology 
ecosystem across sectors.
    With respect to agricultural biotechnology, U.S. leadership is 
essential to ensure that U.S. agriculture can benefit from advances in 
science that reduce its environmental footprint while improving crop 
production. Many U.S. trading partners, including China and Europe, 
maintain unjustified, non-science barriers that delay the approval of 
new plant biotech products. To reduce the potential for trade 
disruption, biotech companies will often delay commercialization of new 
products in the United States until China and Europe haveapproved the 
same products. Such delays impact U.S. competitiveness and cost 
oureconomy dearly. A recent study estimates Chinese delays between 2011 
and 2016 reducedfarm income by $5 billion and U.S. GDP by $7 
billion.\137\
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    \137\ https://www.bio.org/press-release/new-report-shows-
substantial-economic-costs-chinese-delays-ag-biotech-approvals.
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    For new innovations like gene editing, the global regulatory 
landscape is unclear, and there is a risk that genome-edited products 
will be brought under outdated, discriminatory, and highly burdensome 
regulatory frameworks previously adopted for transgenic ag-biotech 
products, even though many of the newer products being developed using 
gene editing do not contain DNA from outside the plants gene pool. This 
creates the potential for enormous barriers to entry for this emerging 
industry, potentially limiting the use of this game-changing technology 
to only a handful of companies and in only large-scale crops. The 
United States currently is working with like-minded governments to 
chart a more reasonable path forward for new innovations in 
biotechnology like gene editing. The U.S. government also has joined 
many governments from across the Americas, Africa, and Asia to support 
agricultural applications of precision biotechnology.\138\ This 
international effort is a clear signal to the world that innovations in 
precision biotechnology, like genome editing, should not face arbitrary 
and unjustified treatment by regulatory authorities. We applaud these 
efforts and encourage renewed urgency in their implementation.
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    \138\ https://www.usda.gov/media/press-releases/2018/11/02/wto-
members-support-policy-approaches-enable-innovation-agriculture.
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Conclusion
    BIO applauds USDA for taking a proactive approach and seeking 
information about facilitating the transformative breakthroughs for 
agriculture to meet the challenges of the 21st Century and increase 
agricultural production by 40 percent while cutting the environmental 
footprint by 50 percent.
    Achieving this goal and addressing the challenges of climate change 
and inequality in society, will require the rapid development and 
deployment of biology-based technologies throughout the agricultural 
supply chain. It will require USDA and the Federal Government to 
establish supportive policies and regulations, provide robust funding 
for research and development, modernize infrastructure, support all 
farmers and ranchers, and build public support of new technologies.
    We urge the Administration to seize the opportunity to expand on 
this American leadership, by acting and supporting the pro-innovation 
technologies and policies we outlined in our comments. We look forward 
to our continued partnership in this critical endeavor.
                                 ______
                                 
Submitted Statements by Hon. David Scott, a Representative in Congress 
                              from Georgia
                              Statement 1
on behalf of barbara p. glenn, ph.d., chief executive officer, national 
            association of state departments of agriculture
    On behalf of the National Association of State Departments of 
Agriculture (NASDA), we appreciate the opportunity to submit this 
statement outlining the priorities of state departments of agriculture 
on policies related to climate resilience. We request that this 
statement be included in the record of the upcoming, February 25th 
hearing of the Committee on Agriculture focusing on ``Climate Change 
and the U.S. Agriculture and Forestry Sectors''.
    NASDA represents the commissioners, secretaries, and directors of 
the state departments of agriculture in all 50 states and four U.S. 
territories. State departments of agriculture are responsible for a 
wide range of programs including food safety, combating the spread of 
disease, and fostering the economic vitality of our rural communities. 
Conservation and environmental protection are also among our chief 
responsibilities.
    In November 2020, NASDA along with several other national 
organizations representing farmers, ranchers, forest owners, the food 
sector, and environmental advocates formed the Food and Agriculture 
Climate Alliance (FACA). This alliance is dedicated to working together 
to define and promote shared climate policy priorities. On November 17, 
2020, FACA released more than 40 policy recommendations to guide the 
development of Federal climate legislation.
    Many of the FACA recommendations are reflective of NASDA priorities 
and we would ask that the Committee on Agriculture consider the 
following as part of any future legislative or oversight activities of 
the Committee:

   NASDA asks that any legislative or oversight activities 
        undertaken by the Congress related to climate focus on 
        advancing science-based outcomes.

   NASDA asks that any legislative or oversight activities 
        undertaken by the Congress promote fairness and equity within 
        the agriculture community through climate solutions.

   NASDA encourages Congress to enact and fund voluntary, 
        incentive-based climate smart agricultural programs as part of 
        the farm bill and other legislative vehicles that consider 
        agriculture's unique role in building resiliency and climate 
        adaptation.

   NASDA asks that the Congress fund research programs and 
        forecasting tools that will help agriculture adapt to the 
        effects of a changing climate, including increased pests and 
        disease, changes in suitable cropping and livestock production 
        systems and increases in extreme weather events.

   NASDA supports expanding Federal tools, including the soil 
        health provisions of the 2018 Farm Bill, to incentivize and 
        measure soil health improvements. Soil health incentives can 
        encourage farmers to adopt practices that improve soil heath 
        and increase carbon sequestration. Improved protocols for 
        measuring the gains in soil carbon from soil health 
        improvements can support development of markets for soil carbon 
        capture and storage.

   NASDA asks that the Congress enact policies that credit 
        ongoing efforts of many farmers and ranchers that have 
        previously adapted climate smart strategies to reduce 
        emissions, sequester carbon, and improve resiliency.

   NASDA supports the creation of voluntary, incentive-based 
        climate smart agricultural programs that are practical, and 
        provide benefits for farmers and ranchers.

    NASDA stands ready to assist this Committee in any way possible as 
it carves a path forward on this important policy issue.
    Please contact Zachary Gihorski (Redacted) if you have any 
questions or would like any additional information.
                              Statement 2
                     on behalf of basf corporation
Background
    BASF Corporation is the largest affiliate of BASF SE. Headquartered 
in Florham Park, New Jersey, it is a leading producer and marketer of 
chemicals and related products in the United States. BASF has the 
broadest portfolio in the chemical industry. Through science and 
innovation, we serve customers in nearly every industry.
    BASF has more than 150 production and R&D sites throughout North 
America, and roughly 14,616 employees in the U.S. and Puerto Rico.
    Research Triangle Park (RTP), North Carolina is the North American 
headquarters for the Agricultural Solutions division including 
regulatory affairs. RTP is also the global headquarters and a major R&D 
site for the Seeds & Traits business and Bioscience Research, as well 
as strategic marketing for herbicides and insecticides, and insecticide 
R&D and formulation development.
Introduction
    Farming today is more complex than ever before; the 
unpredictability of the weather, control of pest and weeds, market 
price volatility, scarcity of natural resources, and all this in a 
world heading toward nine billion people. Farmers are playing an 
increasingly important role today, advancing sustainable agriculture 
practices as the world faces the challenge of feeding a growing 
population with healthy crops, while respecting and preserving limited 
resources.
    The good news is that scientific knowledge is advancing at an ever-
increasing speed. Knowledge of plant genomics, advancements in crop 
breeding techniques, crop protection improvements, and data acquisition 
and interpretation are all opportunities to build a more sustainable 
and resilient food and agricultural system for the future.
    BASF provides farmers with crop protection products, seeds and 
digital solutions designed to sustainably meet their crop production 
needs. We believe that adoption of technology and innovation is one of 
the key elements to reducing agriculture's environmental footprint 
while also making farmers and ranchers more resilient to climate 
change.
BASF Sustainabilty Commitments
    We are continuously introducing sustainable solutions into the 
market to improve quality of life and conserve resources. With that in 
mind, BASF committed to clear and measurable targets to boost 
sustainable agriculture by 2030.
Climate Smart Farming
          Target: 30% reduction in CO2 emissions per ton of 
        crop produced by 2030 in wheat, soy, rice, canola and corn

    BASF will support farmers to become more carbon efficient and 
resilient to volatile weather conditions with technologies that 
increase yield, make farm management more effective, and decrease 
environmental impact.
Sustainable Solutions
          Target: 7% annual increase in our share of solutions with 
        substantial sustainability contribution

    BASF will increase the number of sustainable solutions it brings to 
farmers year by year. Therefore, the company is continuously investing 
in its strong R&D pipeline, steered systematically by sustainability 
criteria. BASF's R&D pipeline contains solutions that support the 
efficient use of resources and reduce the environmental footprint.
Digital Farming
          Target: bring digital technologies to over 980 million 
        cumulative acres of farmland globally by 2030

    Digitalization can make agriculture more resource-efficient and 
sustainable. Therefore, BASF will help farmers with digital tools to 
grow their businesses profitably, while reducing their environmental 
footprint. Using digital technologies allows farmers to produce more 
with less, to make farming processes more efficient from field 
monitoring to the food supply chain. BASF's xarvioT digital products 
enable more precise application of crop protection products, nutrient 
management, automated buffer zones and monitoring of biodiversity.
Smart Stewardship
          Target: To ensure safe use of our products with the right 
        stewardship

    BASF takes its commitment to safety for human health and the 
environment very seriously, offering the right stewardship with every 
product not only to satisfy applicable legal requirements but also to 
ensure the safe use of its products around the farm and in the field. 
The company provides access to stewardship tools and services that are 
tailored to every farmer's daily work. These include protective 
equipment, customized training, digital solutions, and new and future-
oriented application technologies such as drones that reduce working 
time and minimize potential exposure to agrochemicals.
Innovation and Technology As Part of the Climate Solution
    Over the last decades, agriculture technologies and innovation have 
been deployed at a significant scale around the globe, but more can 
still be done. As we work to increase production with limited resources 
and unreliable weather patterns, the continued deployment of new and 
existing technologies will be critical to address climate change.
    Innovations in plant breeding are enabling BASF to enhance yields 
and climate resiliency. The utilization of crop protection innovations 
will also allow farmers to produce more on the same amount of land.
    Additionally, optical sensors have allowed improvements in 
identification of target pests (weeds, insects, and plant pathogens) 
allowing for more targeted applications of crop protection tools and 
fertilizers. Sensors are also used to identify plant stresses like 
water and nutrient deficiencies, or abiotic plant stresses that can 
reduce yield. These sensors will allow for growers to quickly adapt to 
changing environmental conditions during the growing season and will be 
key to manage limited environmental resources.
    The benefit of these technologies can be broad in scope, but below 
are some of the potential outcomes of these innovation solutions:

   Lowering fuel and energy consumption thus reducing carbon 
        dioxide emissions

   Reducing the use of agricultural inputs by pinpointing 
        fertilizer and pest control needs

   Eliminating nutrient depletion through monitoring and 
        managing soil health

   Reducing ecological impact through high-yielding and stress-
        resistant varieties

   Maximizing water use efficiency

    As new technologies are developed, policies based on sound-science 
are necessary to ensure that new products and innovations are reaching 
the marketplace in a transparent and predictable manner so farmers and 
ranchers can take advantage of these tools as they face the increasing 
challenges of climate change.
Conclusion
    BASF appreciates the opportunity to submit these comments and 
stands ready to work collaboratively to assist the U.S. House Committee 
on Agriculture as climate change policy is developed. BASF is well 
positioned to provide input around some of the technologies and 
innovations that will assist farmers and ranchers to become more 
resilient to climate change, while also reducing their overall 
environmental footprint. Thank you again for the opportunity, and we 
look forward to working with you.
                                 ______
                                 
Submitted Letters by Hon. Jim Costa, a Representative in Congress from 
                               California
                                Letter 1
   on behalf of jim mulhern, president and chief executive officer, 
                   national milk producers federation
March 3, 2021

 
 
 
Hon. David Scott,                    Hon. Glenn Thompson,
Chairman,                            Ranking Minority Member,
House Agriculture Committee,         House Agriculture Committee,
Washington, D.C.;                    Washington, D.C.
 

    Dear Chairman Scott and Ranking Member Thompson:

    The National Milk Producers Federation appreciates the opportunity 
to submit testimony for your hearing entitled ``Climate Change and the 
U.S. Agriculture and Forestry Sectors'' held on Thursday, February 25, 
2021 at 12:30 p.m. We look forward to working with you and your 
Committee Members on this critical priority in the coming months.
    The National Milk Producers Federation develops and carries out 
policies that advance the well-being of dairy producers and the 
cooperatives they own. The members of NMPF's cooperatives produce the 
majority of the U.S. milk supply, making NMPF the voice of more than 
32,000 dairy producers on Capitol Hill and with government agencies.
    U.S. dairy farmers have been environmental stewards for decades, 
tending with great care to their land and water, and they value a 
proactive approach to sustainability. As agricultural practices and 
technologies have evolved and improved over time, so too have dairy 
producers adapted. As a testament to dairy's endeavors, greenhouse gas 
(GHG) emissions to produce a gallon of milk dropped nearly 20% over the 
10 years from 2007 to 2017 and the environmental footprint of a gallon 
of milk has significantly decreased since 1944 (e.g., 90% less land, 
65% less water, 63% smaller carbon footprint per unit of milk). We 
believe, however, that more can always be done and therefore support 
efforts to facilitate continuous improvement in this area.
    Unfortunately, sustained low milk prices have made it increasingly 
difficult for dairy farmers to succeed and we are grateful for the 
significant improvements included in the 2018 Farm Bill enacted into 
law. In light of the COVID-19 pandemic which has only served to 
exacerbate these challenges, it is these improvements and more which 
are needed to make both milk production and advanced environmental 
protection a source of economic strength for all dairy farms.
    To continue and enhance our efforts to combat climate change, the 
dairy industry has launched the Net Zero Initiative to reduce the 
industry's climate impact to become carbon-neutral by as early as 2050 
and minimize the water quality impacts of dairy farming. As part of the 
groundwork needed to launch this initiative, the dairy industry has 
worked to develop scientific and economic models to quantify the 
economic and environmental benefits associated with certain dairy farm 
technologies and practices, and various technologies have been 
catalogued and evaluated based on their effectiveness, resilience, and 
business prospects.
    Within the initiative, the industry hopes to deploy several 
demonstration farms around the country to explore the impact of 
multiple technologies and management practices that have an ability to 
aid in reducing dairy's carbon footprint and water quality impact. This 
effort will identify which technologies and practices work well for 
different types of operations, which will help inform policy 
discussions regarding the best ways to expand their adoption in pursuit 
of reducing dairy's environmental impact. In this context, carbon and 
other environmental markets will play an important role in helping us 
to achieve our goal.
    We are eager to advance multiple proactive policy solutions to help 
bring our efforts to fruition. Under this Committee's jurisdiction, 
USDA conservation programs will be instrumental for attaining the dairy 
industry's sustainability improvements over the next 30 years, but 
modifications to these programs will help producers better keep pace 
with scientific and technological advancements. Enteric methane 
emissions account for approximately \1/3\ of a dairy farm's GHG 
footprint. Enhancements could be made to conservation programs to help 
dairy farmers to adopt new approaches to feed management to reduce 
enteric methane emissions and subsequently reduce GHG emissions. USDA's 
NRCS is slated to review its Feed Management Practice Standard in 2021. 
Similarly, the Conservation Stewardship Program could be used more 
substantially to offer manure management practices for soil health 
benefits and cover crop adoption.
    We are also excited to support multiple bipartisan proposals 
previously introduced by Members of this Committee. The Growing Climate 
Solutions Act, authored by Representatives Abigail Spanberger (D-VA) 
and Don Bacon (R-NE), creates a certification program at USDA to help 
solve technical entry barriers that make it difficult for dairy farmers 
and other producers to participate in carbon credit markets. The 
Farmer-Driven Conservation Outcomes Act, authored by Ranking Member 
Thompson and Representative Marcia Fudge (D-OH), directs USDA to 
establish a process for measuring, evaluating, and reporting on 
conservation program outcomes, giving USDA the tools to quantify the 
environmental benefits of related activities.
    Outside of the immediate jurisdiction of this Committee, we support 
a 30 percent investment tax credit, introduced previously as the 
bipartisan Agriculture Environmental Stewardship Act, to cover the 
upfront capital costs of methane digesters and nutrient recovery 
technologies, which can help to reduce methane emissions and enable 
dairy farmers to use nutrients on and off the farm in a more 
sustainable manner. We also support activation of the Electric Pathway 
under the Renewable Fuel Standard (RFS) to provide meaningful new 
environmental opportunities to U.S. dairy farmers. The Electric Pathway 
allows electricity produced on-farm and sold to a commercial electrical 
grid to qualify as a renewable fuel under the RFS, which could yield 
significant dividends as many dairy farmers operate methane digesters 
to produce baseload electricity. Finally, we are urging the Food and 
Drug Administration to expedite its approval process for feed additives 
that can reduce enteric emissions.
    While we have focused these comments on climate-related issues, we 
understand that a brief conversation occurred at the hearing on farm 
milk prices. We are currently working with our membership and across 
the entire dairy community on recommended improvements to policies that 
affect milk pricing, including Federal Milk Marketing Order issues like 
the Class I mover and cheese pricing, to ensure that dairy farmers of 
all sizes and in all regions are treated fairly and equitably. Our 
dairy farmer members from coast to coast are engaged in these 
discussions. It is critically important that these complex issues be 
thoroughly understood in order to help develop the consensus necessary 
to make progress on behalf of all dairy farmers, and are efforts are 
focused on ensuring an informed producer community.
    In closing, we have appreciated the opportunity to work closely 
with you to develop a better safety net and array of risk management 
tools to help dairy producers better weather economic storms like the 
current one, and we are eager to work with you to advance important 
legislation to help the dairy sector build on its already significant 
sustainability efforts. Thank you again for the opportunity to comment.
            Sincerely,

Jim Mulhern,
President & CEO,
National Milk Producers Federation.
                                Letter 2
              on behalf of center for food safety, et al.
May 15, 2020

 
 
 
Hon. Nancy Pelosi,                   Hon. Mitch McConnell,
Speaker,                             Majority Leader,
U.S. House of Representatives,       U.S. Senate,
Washington, D.C.;                    Washington, D.C.;
 
Hon. Kevin McCarthy,                 Hon. Charles Schumer,
Minority Leader,                     Minority Leader,
U.S. House of Representatives,       U.S. Senate,
Washington, D.C.;                    Washington, D.C.
 

    Re: Foodborne Illness Risk from Meat and Poultry Inspection 
            Deregulation

    Dear Speaker Pelosi, Majority Leader McConnell, Minority Leader 
McCarthy and Minority Leader Schumer:

    The undersigned members of the Safe Food Coalition (SFC) write to 
urge you to vote against legislation that would lift prohibitions on 
the interstate sale of meat and poultry from state inspected 
facilities, and allow commercial sales from uninspected ``custom'' 
slaughter facilities, as an amendment to a fourth coronavirus relief 
package. Two proposals in particular--the New Markets for State-
Inspected Meat and Poultry Act of 2019, S. 1720, and the Processing 
Revival and Intrastate Meat Exemption ``PRIME'' Act--would critically 
undermine food safety. At the same time, these laws would do little to 
address the anticompetitive market conditions that are at the heart of 
recent supply chain disruptions in the meat industry.
    In 2018, members of the SFC wrote to the leaders of the Senate 
Agriculture Committee to oppose the New Markets for State-Inspected 
Meat and Poultry Act of 2018, S. 2814, as an amendment to the farm 
bill.\1\ Portrayed as an effort to stimulate new small businesses, that 
legislation would have operated to harm many such enterprises by 
undercutting investments in food safety and increasing the burden of 
foodborne illness on American consumers. Most significantly, S. 2814 
would have substituted uneven state inspection standards and 
enforcement for USDA's meat and poultry inspection program. 
Fortunately, Congressional leaders kept it out of the farm bill. 
However, this misguided legislation has recently commanded new 
attention.\2\
---------------------------------------------------------------------------
    \1\ See Safe Food Coalition Letter to Sen.'s Stabenow and Roberts 
re S. 2814 (June 13, 2018) available at: https://consumerfed.org/
testimonial/safe-food-coalition-opposes-new-markets-for-state-
inspected-meat-and-poultry-act-of-2018/.
    \2\ See, e.g., https://www.rounds.senate.gov/newsroom/press-
releases/rounds-king-lead-colleagues-in-letter-to-senate-leaders-
urging-inclusion-of-new-markets-for-state-inspected-meat-and-poultry-
act-in-next-covid-19-relief-bill.
---------------------------------------------------------------------------
    The proponents of S. 1720 now suggest that passing the law will 
help to alleviate the shortage in beef and pork processing capacity 
that has resulted from the closure of dozens of large meatpacking 
establishments with COVID-19 infection clusters among their workers. In 
a recent letter, the bill's proponents cite statistics indicating that 
beef, pork and poultry production is down by double-digit 
percentages.\3\ Notably, meat and poultry exports, particularly to 
China, have soared during this same time period.\4\ Regardless, what S. 
1720's proponents fail to mention is that the capacity of state-
inspected slaughter facilities is negligible compared to the massive 
federally inspected facilities that have closed. Overall, federally 
inspected facilities produce 98.9% of red meat sold in the United 
States.\5\ Allowing interstate sales from state-inspected 
slaughterhouses therefore will have no significant impact on the 
``backlogs'' of animals planned for slaughter.
---------------------------------------------------------------------------
    \3\ Id.
    \4\ https://www.reuters.com/article/us-usa-pork-braun/us-faces-
meat-shortage-while-its-pork-exports-to-china-soar-braun-idUSKBN22H2Q6.
    \5\ See USDA National Agricultural Statistics Service ``Livestock 
Slaughter, 2018 Summary,'' p. 7 (April 2019), available at: https://
downloads.usda.library.cornell.edu/usda-esmis/files/r207tp32d/
8336h934w/hq37vx004/lsslan19.pdf.
---------------------------------------------------------------------------
    More importantly, as SFC members explained in the 2018 letter, 
allowing interstate sales of meat and poultry from state inspected 
plants would expose consumers to increased foodborne illness risk. 
State meat and poultry inspection programs are not actually ``equal'' 
to Federal inspection, with arguably the exception of six states from 
which USDA already allows state inspected processors to ship across 
state lines through the Cooperative Interstate Shipment (CIS) program. 
Moreover, no state has authority to require a recall of adulterated 
food that has been inspected in a different jurisdiction, or to bar the 
sale of meat and poultry inspected by state programs with questionable 
safety records. S. 1720 would therefore increase the risk that 
adulterated meat and poultry will be sold and consumed. It would also 
create unfair competition for processors, including very small ones, 
who have invested in meeting Federal inspection requirements, it would 
undermine public confidence in the safety of the food supply because 
consumers would not be assured of Federal inspection, and it would 
undermine confidence in the government because none of these issues has 
been the subject of hearings in either house of Congress.
    The PRIME Act has similarly evaded serious scrutiny up to now. The 
bill would allow meat and poultry from an uninspected ``custom 
slaughter facility'' to be sold to consumers at ``restaurants, hotels, 
boarding houses, grocery stores, or other establishments located'' 
within the state's borders. There is no size limitation on the 
facilities that might avail themselves of this exemption, nor any 
prescriptions for states regarding how, or whether, they regulate these 
``custom'' establishments before their products are unleashed on 
unwitting consumers. Under current law, the custom slaughter exemption, 
which the PRIME Act would ``amend,'' does not allow product from these 
facilities to enter into commerce. They are ``exclusively for use by 
[the animal owner] and members of his household and his nonpaying 
guests and employees.'' 21 U.S.C. 623(a). The PRIME Act would be a 
dramatic departure from long-established food safety protections.
    The COVID-19 pandemic has exposed vulnerabilities in our food 
system, and nowhere is this more apparent than in our meat and poultry 
slaughterhouses, where decades of industry consolidation has 
concentrated workers into large, crowded establishments where disease 
can spread swiftly, shutting down large segments of the food supply 
overnight. Yet Congress must not address these shortcomings by undoing 
the vital inspection safeguards that ensure the safety of our food. 
Rather than undermine Federal inspection requirements, we urge Congress 
to work with USDA and state authorities to extend and strengthen the 
existing Cooperative Interstate Shipment (CIS) program, laying the 
groundwork to support and enhance local and regional supply chains 
while also ensuring food safety standards are met.
    We respectfully urge you to consider these issues, and to maintain 
food safety protections for meat and poultry shipped in interstate 
commerce and otherwise sold to consumers.
            Sincerely,

 
 
 
Center for Food Safety               Consumer Reports
Center for Science in the Public     Food & Water Watch
 Interest
Consumer Federation of America       National Consumers League
 

                                Letter 3
       on behalf of national cattlemen's beef association, et al.
May 15, 2020

    Dear Members of Congress:

    The undersigned organizations submit this letter opposing inclusion 
of the New Markets for State-Inspected Meat and Poultry Act (S. 1720 or 
the bill) in the next COVID-19 supplemental response bill. If enacted, 
S. 1720 would amend the Federal Meat Inspection Act and Poultry 
Products Inspection Act and allow state-inspected meat and poultry 
products to be sold in interstate commerce.
    The United States' Federal inspection system for meat and poultry 
products is the gold standard for the world. Not only would allowing 
interstate shipment of state-inspected meat and poultry as contemplated 
by the bill raise questions internationally, but the ability of state 
inspected plants to ship interstate was addressed 12 years ago.
    The long running debate regarding allowing interstate shipment of 
state-inspected meat was resolved in the 2008 Farm Bill with the 
establishment of the Cooperative Interstate Shipment (CIS) program. 
That program allows small- and medium-sized state-inspected plants to 
ship product in interstate commerce if they satisfy the same rules 
their federally inspected counterparts meet. Every state with an 
inspection system can participate in the CIS program but only six 
states \1\ have given their state-inspected plants this opportunity. In 
other words, state inspected plants that cannot ship in interstate 
commerce are being denied the opportunity by their state governments, 
not USDA.
---------------------------------------------------------------------------
    \1\ https://www.fsis.usda.gov/wps/portal/fsis/topics/inspection/
state-inspection-programs/cis/states-participating.
---------------------------------------------------------------------------
    Despite what some bill proponents assert, this issue is not about 
``big packers'' versus ``small packers.'' Thousands of small and very 
small packers and processors are subject to daily Federal inspection 
and enjoy the benefits it provides, including access to national and 
international markets. That there are thousands of small and very small 
federally inspected plants disproves the myth perpetuated by S. 1720 
proponents who assert it is too difficult to meet Federal requirements. 
Those thousands of small and very small Federal processors deserve a 
level playing field where every company selling in interstate commerce 
is playing by the same set of rules.
    Operating under state inspection is a business decision, it is not 
compulsory. Companies select the inspection regime that best fits their 
business needs. Changing the rules to allow state-inspected meat into 
interstate commerce would disadvantage the small and very small 
federally inspected plants that have invested time and money to develop 
food safety systems that comply with Federal requirements.
    The U.S. Department of Agriculture's Food Safety Inspection Service 
has a small and very small plant outreach program specifically designed 
to assist such plants with a variety of food safety and other issues. 
If a state-inspected plant makes the business decision it wants to ship 
interstate, there are numerous resources, including the small and very 
small plant outreach program, to help it transition to Federal 
inspection.
    In addition, the bill would create a food safety regulatory 
nightmare. State inspection authorities have no legal authority to 
control the disposition of product shipped outside their state. If, for 
instance, a State X inspection authority discovered adulterated product 
had been shipped out of state, that State X would have no legal 
authority to take regulatory action outside its state boundaries. 
Conversely, if a product causes illnesses in State Y, not the state of 
origin, there would be no way for State Y to take regulatory action in 
the state of origin, assuming the product is traceable.
    Allowing interstate shipment of state-inspected meat could also 
hurt international trade. State inspected product could find its way to 
processors as an ingredient in processed product that is exported, 
despite strict prohibitions. Or, more likely, another country would use 
the fear of state-inspected product being exported as an excuse for 
establishing non-tariff trade barriers against U.S. meat or poultry. 
The risk of damaging U.S. meat and poultry exports is real and too 
great to allow interstate shipment of state-inspected product.
    Meat and poultry imports systems also would be thrown into chaos. 
If state-inspected products may be sold in interstate commerce, to meet 
its international obligations, the U.S. would have to accept imported 
meat and poultry from local and provincial inspection systems in 
foreign countries. Such an outcome would present an unacceptable food 
safety risk to U.S. consumers.
    The discussion above demonstrates the reasons to oppose S. 1720 are 
many and for all of them the undersigned organizations oppose efforts 
to amend the Federal Meat Inspection Act and the Poultry Products 
Inspection Act to allow interstate shipment of state-inspected meat and 
poultry products.
            Sincerely,

 
 
 
National Cattlemen's Beef            National Turkey Federation
 Association
National Chicken Council             North American Meat Institute
National Pork Producers Council
 

                                 ______
                                 
Submitted Report by Hon. Chellie Pingree, a Representative in Congress 
                               from Maine
Maine Forestry and Agriculture Natural Climate Solutions Mitigation 
        Potential_Interim Report
        
        
        
        
          Cover photos credits: Garlic in mulch courtesy Johnny 
        Sanchez; Howland Research Forest from carbon flux tower 
        courtesy Meg Fergusson.

Adam Daigneault, Erin Simons-Legaard, Sonja Birthisel, Jen Carroll, 
Ivan Fernandez, Aaron Weiskittel, University of Maine

August 2020


Table of Contents
Executive Summary
1. Introduction
2. Methodology

    2.1  Estimating Costs and Benefits of GHG Mitigation
    2.2  Forestry

          2.2.1  Overview
          2.2.2  Forest NCS Practices/Scenarios
          2.2.3  Landis-based modeling
          2.2.4  Non-Landis modeling
          2.2.5  Forest Carbon and Cost Estimation
          2.2.6  Sensitivity Analysis

    2.3  Agriculture

          2.3.1  Overview
          2.3.2  NCS Practices/Scenarios
          2.3.3  Analytical Approach
          2.3.4  Agricultural enterprises
          2.3.5  NCS Mitigation costs and effectiveness by practice
          2.3.6  Sensitivity Analysis

3. Results

    3.1  Forestry
          3.1.1  Model Baseline
          3.1.2  Forest NCS practice results

                  3.1.2.1  Forest management in Landis
                  3.1.2.2  Afforestation and avoided conversion
                  3.1.2.3  Summary of core modeled results

          3.1.3  Sensitivity Analysis

                  3.1.3.1  Climate change impacts sensitivity
                  3.1.3.2  Economic benefits and costs sensitivity

    3.2  Agriculture

          3.2.1  Model Baseline
          3.2.2  Agriculture NCS practice results

4. Summary & Conclusions
Appendix A. Detailed Results
Appendix B. Detailed Input Data

    Maine forest systems
    Maine cropping systems
    Natural Climate Solutions for Agriculture

Appendix C. Statewide extrapolation of forest carbon estimates
References
Executive Summary
    The State of Maine has recently set a goal to reduce gross 
greenhouse gas (GHG) emissions by 80% by 2050 and to have their net 
GHGs (gross emissions less carbon sequestration from forestry, 
agriculture, and marine sources) be equal to zero or `net zero' by 
2045. To achieve climate goals, we must also look for ways to remove 
carbon from the atmosphere (i.e., negative emissions) and sequester it 
in soils. Natural climate solutions (NCS), such as cropland nutrient 
management, planting trees, and conservation, that sequester carbon or 
limit GHG emissions can affect near-term GHG mitigation goals in cost-
effective ways and enhance long-term ecosystem services. However, a 
comprehensive assessment of potential NCS practices and their cost/
benefits across Maine's primary sectors has yet to be attempted.
    This report is part of the larger `Maine Natural Climate Solutions 
Initiative' project that seeks to: (1) assess current practices to 
determine the degree to which foresters and farmers are using NCS; (2) 
determine the most cost-effective NCS for Maine; (3) understand key 
barriers to adopting NCS; and (4) generate information about which 
practices can be implemented on a broader scale. This was done by 
modeling a `baseline' or `business as usual' (BAU) pathway, to which 
all other scenarios or pathways were compared or measured against. 
Next, a list of potential NCS practices that could feasibly be 
implemented in Maine was established by a mix of expert input and data 
availability. Finally, an estimate of the `cost' and `effectiveness' of 
implementing the NCS practices under consideration was determined.
    Maine's forests currently sequester nearly 70% of the state's 
annual gross greenhouse gas emissions and continued to do so under a 
range of alternative management scenarios and potential futures. Using 
a forest landscape model and data available for 9.1 million acres of 
forest in northern Maine, it was determined that most forest management 
NCS practices can be implemented at a cost of $10-$20 per ton carbon 
dioxide equivalent (tCO2e), which is relatively inexpensive 
compared to most non-NCS opportunities (Table ES1). Increasing the 
intensity of active forest management could yield about 4.5 million 
tCO2e/yr for this study area in additional carbon 
sequestration at a cost of $64 million/yr or $14/tCO2e, 
which was significantly more effective than increasing rotation 
lengths. All scenarios tested have minimal potential leakage, while 
additional ecosystem services benefits were realized with some of the 
scenarios.
    For Maine agriculture, farmers could collectively amend their soil 
with biochar, reduce their tillage intensity, plant riparian buffers, 
and construct and utilize anaerobic digesters to manage dairy manure 
waste, thereby mitigating up to 786,000 tCO2e/yr in GHG 
emissions or about double the sector's current annual emissions (Figure 
ES1). This combined approach for the agricultural sector is estimated 
to cost $26.3 million/yr or $34/tCO2e. Consequently, setting 
aside the issue of uncertainties, this analysis showed that Maine's 
agricultural sector has the potential to reduce its within-sector 
emissions or even be net-negative as a sector.
    Although the analysis has some important limitations that will be 
refined in future efforts, this work represents a critical first step 
for exploring the potential benefits of incorporating NCS in Maine's 
climate action implementation. Currently, interviews and focus groups 
are being used to explore the potential technical, financial, social, 
and/or policy barriers and opportunities that stakeholders face in 
implementing the NCS practices. These findings will be incorporated 
into future modeling efforts and annual progress reports.
Figure ES1.
($/tCO2e)


          Summary of Maine NCS mitigation potential (tCO2e/
        yr) and break-even carbon price.
1. Introduction
    The State of Maine has recently set a goal to reduce gross 
greenhouse gas (GHG) emissions by 80% by 2050 and to have their net 
GHGs (gross emissions less carbon sequestration from forestry, 
agriculture, and marine sources) be equal to zero or `net zero' by 2045 
(An Act To Establish the Maine Climate Change Council To Assist Maine 
To Mitigate, Prepare for and Adapt to Climate Change, 2019). The Maine 
Department of Environmental Protection (DEP) tracks gross GHG emissions 
from numerous sources including the energy and agricultural sectors; 
however, they do not account for carbon (C) sequestration from the 
state's land use sectors (Eighth Biennial Report on Progress Toward 
Greenhouse Gas Reduction Goals, 2020). Furthermore, it is uncertain how 
many additional mitigation measures could be taken to help reduce 
Maine's GHG emissions, nor what it might cost to implement these 
practices.
    Maine's GHG reduction goals reflect the evidence of current and 
potential future harmful impacts climate change could have on the 
state's people and ecosystems. Milder winters and earlier springs will 
adversely impact forestry and farming in Maine (Dupigny-Giroux, et al., 
2018). The Northeast is warming faster than the rest of the U.S. 
(Karmalkar & Bradley, 2017), and Maine's temperature has increased by 
3.2 Fahrenheit since 1895, with greater increases along the coast. In 
Maine, we are acutely aware of the changing conditions in the Gulf of 
Maine, particularly in marine fisheries, and coastal communities. 
However, Maine's terrestrial environment is also being strongly 
influenced by changing climatic conditions that are likely to place 
increasing stress on Maine's forests, particularly those species that 
are either at their northern or southern limit, or vulnerable to 
emergent pests and pathogens. The growing season in Maine is two weeks 
longer than it was in 1950, and the state is experiencing an increase 
in precipitation intensity, with more likely to come (Fernandez, et 
al., 2020). This increased precipitation can cause delays in planting, 
soil compaction, soil erosion, and agricultural runoff. The frequency 
of heavy rainfall events before the final frost has been increasing and 
could prevent farmers from taking advantage of earlier springs and 
reduce the number of days that fields can be worked because they are 
overly wet (Wolfe, et al., 2018). Scientists also expect warmer winters 
to increase the pressure from pests and weeds. Of importance for Maine, 
rural communities have limited economic resilience because of a lack of 
redundancy in infrastructure and therefore have a limited ability to 
manage climate change impacts (Dupigny-Giroux, et al., 2018). Adopting 
new technologies, modifying management practices, and changing which 
commodities are produced can help forestry and agricultural systems 
adapt; however, there are limits to adaptive capacity and more 
strategies need to be developed (Gowda, et al., 2018).
    Recent studies have emphasized the need to do more than reduce GHG 
emissions from fossil fuels if increasingly costly impacts are to be 
avoided. To achieve climate goals, we must also look for ways to remove 
carbon from the atmosphere (i.e., negative emissions) and sequester it 
in soils. Natural climate solutions (NCS), such as reducing tillage 
intensity, planting perennial grasses and trees, and setting aside land 
that sequesters carbon or limits GHG emissions can affect near-term GHG 
mitigation goals in cost-effective ways and enhance long-term ecosystem 
services. Within the United States, NCS have the potential to mitigate 
21% of net annual GHG emissions (Fargione, et al., 2018). However, 
stakeholders from throughout Maine and the U.S. have determined that 
foresters and farmers need additional policies, tools, and incentives 
to adopt practices that promote better soil health at a scale that 
significantly contributes to climate change mitigation and adaptation.
    There is a need for an accessible way for stakeholders to evaluate 
and prioritize the various practices that could be used to achieve GHG 
mitigation goals, and Maine-specific analyses will inform the state 
climate action plan and enhance effective implementation of NCS 
practices. To date, most NCS studies are global and national-scale, and 
state-level estimates are often reliant on assumptions more applicable 
elsewhere. The practices covered are also often typical of more 
conventional forestry or agricultural systems. Moreover, Maine 
foresters and farmers may face unique implementation barriers important 
in the state, but are not evident elsewhere. The analysis presented in 
this report attempts to address these considerations by helping to 
identify efficient, cost-effective solutions to improve forest and 
agronomic land management, reduce carbon-negative land use change, and 
promote soil health in Maine.
    This report is part of the larger `Maine Natural Climate Solutions 
Initiative' project which seeks to (1) assess current practices to 
determine the degree to which foresters and farmers are using NCS; (2) 
determine the most cost-effective NCS for Maine; (3) understand key 
barriers of adopting NCS; and (4) generate information about which 
practices can be implemented on a broader scale.
    The report is organized as follows. First, we present the general 
methodology for estimating potential impacts from implementing NCS 
across Maine. Next, we present the model baseline and results from a 
wide range of scenarios and practices applied to the state's forest and 
agricultural sectors. We then conclude the main report with a summary 
of the key findings. Two appendices provide additional detail on the 
study results and model input data.
2. Methodology
2.1  Estimating Costs and Benefits of GHG Mitigation
    The main objective of this study was to estimate the GHG mitigation 
benefit and costs of implementing NCS practices in Maine's forest and 
agricultural sectors. First, to achieve this a model `baseline' or 
`business as usual' (BAU) pathway was established that all other 
scenarios or pathways will be compared to or measured against. In this 
case, we assumed a continuance of current policy and practices that 
essentially maintain the harvest, cultivation, and planting rates that 
have been apparent over the past decade. Second, we needed to define 
the geographical and temporal scale of the baseline. The framework for 
this study focused on impacts to two sectors (agriculture and forests) 
across the entire state, with a key exception of some of the forest 
modeling, which utilized a case study approach for a block of nine 
million acres of managed forestland in the northern part of the state. 
In terms of temporal scale, forest impacts were measured through 2100 
(80 years), while the agriculture sector impacts were measured over the 
next 20 years. Third, we specified the environmental conditions that 
the model baseline should follow, namely the effect of climate change 
on biophysical growth and yield. In this analysis, the forestry 
modeling baseline assumed that Maine's climate would follow a low 
emissions and impacts trajectory, specifically the Representative 
Concentration Pathway (RCP) 2.6. We did not assume any climate change 
impacts for the agricultural sector due to lack of data.
    The next key aspect of designing a mitigation modeling study was to 
establish a list of potential NCS practices that could feasibly be 
implemented in Maine. During such a process, there is often a debate 
about what mitigation should be included, both from a biophysical and 
socioeconomic perspective. Policy constraints and concerns about land-
based mitigation practices include ways to properly `measure, monitor, 
and verify' that practices are being implemented correctly and whether 
issues with permanence, additionality, and leakage make the project a 
risky investment. The set of NCS practices that we opted to analyze in 
this report was decided through a mix of expert input and data 
availability.
    The last key aspect of the analysis was to estimate the `cost' 
 and `effectiveness' of implementing the NCS practices under consideration. 
This is typically done using a suite of applications and methods that 
integrate both economic and biophysical modeling. Most of these models 
attempt to be empirically based but can be complicated by the complex 
nature of the land use sector. Implementing NCS practices across 
Maine's landscape is likely to accrue a number of costs and benefits 
relative to the baseline or BAU. Key benefits could include reduced 
GHGs or increased carbon sequestration, yield improvements, cost-
savings from reduced expenditures, and other environmental benefits 
such as improved soil health and water quality (Figure 1). Key costs 
that may accrue include added capital, labor, and maintenance costs, 
land acquisition costs, yield (and revenue reductions), and loss in 
harvestable area. The latter two can be considered opportunity costs 
because it is essentially the income that one is willing to forego to 
achieve the benefits associated with implementing the practice. All 
monetary values in this study are inflation adjusted and reported in 
2017 real dollars.
Figure 1. 


          Key costs and benefits of implementing natural climate 
        solutions relative to business as usual.

    Figure 2 provides an illustrative example of how the average 
benefits and costs of a given NCS practice are calculated, specifically 
the impact of shifting from intensive to reduced-till farming across 
50,211 acres of potatoes planted in Maine. In this case, each acre of 
land converted to reduced-till is estimated to provide 0.10 metric tons 
of carbon dioxide equivalent (tCO2e) per year of additional 
carbon sequestration, equating to just over 5,000 tCO2/yr in 
total mitigation across the state. That amount of mitigation can then 
be used to estimate the total cost and/or the cost relative to their 
baseline practice by multiplying the total area converted by the mean 
net revenue (commodity output revenue less input costs) change, which 
equates to about $1.1 million per annum, or $21.80/ac. This figure can 
then be converted into the amount that an average potato farmer may be 
willing to accept to `break even' by implementing this practice, which 
is quantified using the common mitigation cost metric of $/
tCO2e. In this example, that break-even carbon price for 
converting all eligible intensively tilled potato area in Maine to 
reduced till is estimated to be $218/tCO2e. We replicated 
this methodology for the dozens of crop and forest management scenarios 
that we describe in detail below.
Figure 2. 


          Example of how to calculate biophysical potential and 
        economic cost of converting all eligible Maine potato farms 
        from intensive to reduced crop tillage.
2.2  Forestry
2.2.1  Overview
    Forests currently cover about 17.5 million acres or nearly 89% of 
Maine's area. The forest industry sector is statewide, multi-faceted, 
and provides about $8 billion/yr in direct economic impact. 
Furthermore, Maine's forests currently sequester nearly 70% of the 
state's annual gross greenhouse gas emissions (Domke, et al., 2020; 
Eighth Biennial Report on Progress Toward Greenhouse Gas Reduction 
Goals, 2020), as carbon stored in new forest growth and harvested 
products is greater than the amount removed (Figure 3). However, 
significant changes to both natural forest and industry are expected in 
the decades to come via shifts in market demand, policy adjustments, 
and climate change. Furthermore, Maine's forest is a transitional 
ecotone with a broad mixture of species, which means that changing 
climatic conditions create significant stress as most species are 
either at their northern or southern limit. As a result, we seek to 
analyze the potential impacts on Maine's forest carbon sequestration 
through 2100 under a range of different management regimes. 
Furthermore, we evaluate the impact of our assumptions via sensitivity 
analysis. This section provides an overview of how the modeling of 
forest natural climate solutions was conducted.
Figure 3. Maine GHG Emissions and Forest Carbon Removals, 1990-2017 


          Source: Domke, et al., 2020; Maine DEP, 2020.
2.2.2  Forest NCS Practices/Scenarios
    We modeled a number of different forest practices with NCS 
potential that varied the approach to forest management and use on the 
nine million acre case study block of land in Maine. We established 
seven scenario foci with many including more than one set of scenarios 
within each focus (Table 1).
    These were:

  1.  Extended Rotation: increased minimum stand age eligible for 
            harvest from BAU 50 year to 85 or 100 years.

  2.  Clearcut/Partial harvest distribution: increased % of the area 
            harvested by clearcut (from 10% to 35% or 50%). Wood supply 
            was held constant by proportionally reducing overall 
            harvest footprint, assuming on average 1 acre of clearcut 
            would result in the same volume harvested as 2 acres of 
            partial harvest.

  3.  Planting: added planting (or artificial regeneration) after 
            clearcut with a 700 tree per acre mix of red and white 
            spruce.

  4.  Set-aside: Reserved 10% or 20% of forestland, which was 
            permanently removed from harvest.

  5.  Triad approach: Mix of BAU rotations, clearcuts with planting, 
            and permanent set-asides.

  6.  Avoided Forest Conversion: Held 2010 forest area constant via 
            renting land at cost of highest and best use if converted.

  7.  Afforestation: Plant trees in eligible areas not forested since 
            at least 1990.

    Impacts to aboveground carbon, harvested wood carbon, revenues, and 
costs were estimated using a mixed modeling approach, with most of the 
scenarios conducted with Landis, a landscape-level dynamic forest 
ecosystem model.

    Table 1. Forest NCS Practices modeled with and without Landis-II.
------------------------------------------------------------------------
 Scenario  Scenario                Min. Stand   Plant after   % Land Set
  Focus      Name     % Clearcut      Age        Clearcut       aside
------------------------------------------------------------------------
                         Landis-based Scenarios
------------------------------------------------------------------------
Baseline/  BAU age            10           50           No             0
 BAU        (min
            50)
Extended   Min 85             10           85           No             0
            years
Rotation   Min 100            10          100           No             0
            years
Clearcut/  35%                35           50           No             0
 Partial    Clearcu
            t (CC)
Harvest    50% CC             50           50           No             0
 Dist.
Clearcut   35% CC,            50           50          Yes             0
 & Plant    plant
           50% CC,            50           50          Yes             0
            plant
Set-aside  10% set-           10           50           No            10
 forest     aside
land       20% set-           10           50           No            20
            aside
Triad      35% CC,            35           50          Yes            10
 Approach   plant,
            10% set
            aside
           35% CC,            35           50          Yes            20
            plant,
            20% set
            aside
------------------------------------------------------------------------
                          Non-Landis Scenarios
------------------------------------------------------------------------
Afforesta  Afforest           10           50           No             0
 tion       ation
Avoided    Avoided            10           50           No             0
 conversi   convers
 on         ion
------------------------------------------------------------------------

2.2.3  Landis-based modeling
    Forest landscape models (FLMs) have become an essential tool for 
predicting the broad-scale effects of anthropogenic and natural 
disturbances on forested landscapes. One open-source FLM that has 
become widely used to compare alternative future scenarios across large 
areas is the LANDscape DIsturbance and Succession (LANDIS) model 
(Gustafson, et al., 2000; David J. Mladenoff, 2004; Scheller, et al., 
2007). First released in the mid-1990s, LANDIS was designed to 
stochastically simulate the spatio-temporal effects of repeated 
interactions between forest disturbance and succession based on a 
moderate number of user-specified parameters (D.J. Mladenoff, et al., 
1996; D.J. Mladenoff & He, 1999). Since its release, LANDIS or the 
updated version LANDIS-II have been used in more than 100 peer-reviewed 
publications to simulate the impacts of a wide variety of disturbances 
for which model extensions have been developed.
    Within LANDIS-II, the forest is represented by a raster grid of 
interacting cells, aggregated by user-defined ecoregions (homogenous 
soils and climate). Successional processes including tree 
establishment, growth, competition, and mortality are modeled for each 
cohort (i.e., group of trees defined by species and age) in each cell, 
and emergent conditions (e.g., aboveground biomass) are tracked for 
each cohort. Each cell can contain multiple cohorts, and initial forest 
conditions are generally provided by, for example, land cover or forest 
type maps. Cells are modeled as spatial objects linked by the processes 
of seed dispersal, natural disturbance, and land use. Execution of 
LANDIS-II requires the parameterization of tree species life history 
attributes, specification and parameterization of key ecological 
processes, and spatial representations of initial forest and landscape 
conditions.
    We used LANDIS-II to model the effects of alternative management 
strategies on the carbon dynamics of Maine's 13 most abundant tree 
species (Appendix B) between 2010 and 2070. Circa 2010, these 13 
species comprised 86% of Maine's aboveground forest biomass. Initial 
forest conditions were provided by maps of tree species relative 
abundance developed for our study area using USFS Forest Inventory and 
Analysis plot data and Landsat satellite imagery.\1\ Our study area 
(Figure 4) encompassed approximately 9 million acres of primarily 
commercial forestland. Owners within this area are predominantly 
considered large (>10,000 acres) land owners and represent a diverse 
range of ownership types (e.g., Family, Timber Investment Management 
Organizations, Real Estate Investment Trusts, and Nonprofit 
Organizations).
---------------------------------------------------------------------------
    \1\ Following the methods of Legaard, et al., 2020.
---------------------------------------------------------------------------
Figure 4. 


          Project study area for forest landscape projections using 
        LANDIS-II encompassed approx. 9.1 million acres of 
        predominantly commercial forestland in northern Maine.

    The LANDIS-II model comprises a core program and user-selected 
modules that have been developed to simulate succession and a variety 
of disturbance agents. We used the Biomass Succession module (Scheller 
& Mladenoff, 2004) to model forest growth and succession, the Base Wind 
module (Scheller, et al., 2007) to model blowdown, and the HARVEST 
module (Fargione, et al., 2018) to model timber harvesting. We modeled 
two harvest prescriptions: clearcut and partial harvest. Partial 
harvests were designed to remove an average of 50% of the live biomass 
from a stand. Biomass removal was variable, representing a combination 
of complete overstory removal within harvester trails and uniform 
selection in the remainder of the selected stand. Our baseline or 
Business-as-Usual (BAU) scenario emulated the average cumulative 
harvest rate within the study area, as estimated from a Landsat-derived 
time series of forest disturbance (2000-2010) (K.R. Legaard, 2018). The 
BAU scenario (hereafter referred to as BAU min50) set the minimum stand 
age eligible for harvest as 50 years old, which follows historical 
trends for Maine timber harvests.
    Annual net primary productivity (ANPP) is a key parameter in the 
modeling of forest growth and succession within LANDIS-II. We used the 
process-based PnET-II model (Aber, et al., 1995) to estimate ANPP for 
each species in a manner similar to previous LANDIS-II studies 
(Ravenscroft, et al., 2010). PnETII predicts monthly changes in 
photosynthesis and the production of biomass (foliar, wood, root) using 
species-specific traits (e.g., foliar nitrogen) and climate inputs, 
including average minimum/maximum surface temperature and total monthly 
precipitation. To estimate future (2020-2070) ANPP for each species we 
incorporated monthly, downscaled climate projections for our study 
area. Gridded projections were based on the AO (Atmospheric-Oceanic) 
variant of the Hadley global environment model v2 (HADGE-AO) under a 
low-emission scenario (RCP 2.6) and obtained from the USGS Geo Data 
Portal (USGS Geo Data Portal, 2020).
    Over the course of a simulation, LANDIS-II tracks aboveground 
biomass for each cohort in each cell, along with species and age 
information, and reports the results at a user-specified interval. We 
ran LANDIS-II at a 10 year time step and based on the results 
calculated total aboveground carbon at each interval 2010-2070 for each 
forest management scenario. In addition, for demonstration purposes we 
compared the status of a variety of ecosystem services ca. 2060 under a 
subset of the management scenarios relative to our baseline. We 
included spruce-fir carbon, late successional forest (>100 years old) 
for both spruce-fir forest (>75% balsam fir, spruce sp. relative 
abundance) and northern hardwood (>75% sugar maple, yellow birch, 
American beech relative abundance), as well as lynx foraging habitat 
(regenerating forest <40 years old with >50% spruce-fir relative 
abundance).
2.2.4  Non-Landis modeling
    Two of the forest NCS assessments were estimated for the entire 
State of Maine based on a methodology that did not utilize the LANDIS 
model: (a) afforestation of marginal non-forest land with trees, and 
(b) avoided conversion of current forestland that is considered under 
threat of being changed into developed or agricultural use.
    The afforestation (or forest restoration) estimates were derived 
based on methods from Cook-Patton, et al. (2020), which evaluated the 
potential for the contiguous U.S. at a high spatial resolution. 
Locations were initially constrained to areas where forests with %25% 
tree cover historically occurred. Additional assumptions excluded all 
cropland not located in areas with challenging soil conditions,\2\ all 
developed land not designated in the National Land Cover Database as 
`open space', and land designated as protected or wilderness areas. In 
total, we estimated that about 360,000 acres of land in Maine met the 
criteria for afforestation, with 65% of the area coming from pasture/
grassland, 25% from open space, 10% from cropland, and the remainder 
from `other' land covers. Afforested land was assumed to primarily be 
via natural regeneration and include a mix of tree species already 
growing in Maine. Annual tree biomass and carbon sequestration 
estimates from afforestation were derived from FIA. Mitigation costs 
included opportunity cost of the alternative land use (due to lost 
future revenue) as well as stand establishment and maintenance costs. 
Pasture and cropland values were based on USDA Cropland Reserve Program 
(2020) rental rates (where land has typically `marginal' productivity), 
while developed land values were obtained from Davis, et al. (2020).
---------------------------------------------------------------------------
    \2\ Areas with challenging soil conditions were identified using 
land capability classes 4e, 5w, 6, 7, or 8 in the Gridded Soil Survey 
Geographic Database (https://gdg.sc.egov.usda.gov/).
---------------------------------------------------------------------------
    Avoided forest conversion (i.e., deforestation) estimates were 
derived from methods similar to Fargione, et al. (2018). Future 
conversion was based on extrapolating historical trends forward, 
following the New England Landscape Futures (NELF) (New England 
Landscape Futures Explorer, n.d.) baseline projections. According to 
NELF, approximately 8,500 acres of land are estimated to be converted 
to development or agricultural land in Maine each year, with 76% of the 
conversion going to development (Figure 5. Projected Cumulative Maine 
land cover change, 2010 to 2060. (Source: NELF, 2020)). Costs of 
mitigation included opportunity costs of land sale, using the same 
sources as the afforestation estimates. Carbon sequestration estimates 
were based on an `average' Maine stand in FIA, and assumed to 
accumulate at a mean rate of 3.1 tCO2e/ac/yr. That is, 
landowners who are compensated for not converting their forest to other 
uses would be paid initially for maintaining their existing carbon 
stock as well as the additional carbon that could be accrued on their 
stand in the years after the initial payment.
Figure 5. Projected Cumulative Maine Land Cover Change, 2010 to 2060 


          Source: NELF, 2020.
2.2.5  Forest Carbon and Cost Estimation
    As discussed above, forest carbon sequestration was primarily 
estimated using FIA data. In addition to evaluating impacts of 
different practices on aboveground growing stock of biomass and carbon, 
we also estimated the potential change in carbon in harvested wood 
products and landfills over time. The harvested wood product and 
landfill estimates were derived using the methods from Smith, et al. 
(2006), and were roughly equivalent to 20% of the total biomass/carbon 
removed/harvested from the stand (Bai, et al., 2020). The remaining 
harvested carbon was assumed to be emitted immediately, either through 
combustion for energy or otherwise (Smith, et al., 2006). Total carbon 
sequestration in any given year was the sum of aboveground forest 
carbon and harvested wood and landfill carbon.
    Economic benefits and costs from implementing different types of 
forest practices were based on four primary components: (a) harvest 
revenue, (b) land acquisition costs, (c) planting costs, and (d) 
opportunity costs. Harvest revenues were estimated by multiplying the 
biomass harvested by mean state stumpage price for each product 
harvested (Annual Stumpage Price Reports, 2020). Planting costs were 
assumed to be a mix of seedlings ($0.37/plant) planted at a density of 
800 trees per acre ($296/ac) and site prep which included two spray 
applications ($250/ac), for a total of $546/ac. Land acquisition costs 
and annual rents varied by current or highest and best use and were 
acquired from USDA (Cropland Reserve Program Statistics, 2020) and 
Davis, et al. (2020) Finally, opportunity costs were estimated as the 
change in harvest and other land use revenue relative to the baseline 
or business as usual case. We note that there are cases where revenues 
can potentially be higher than the BAU estimate, such as plantations on 
stands that were initially naturally regenerated.
2.2.6  Sensitivity Analysis
    The Landis-based scenarios already evaluated the effect of varying 
minimum stand harvest age, percentage of land designated as no-harvest 
set asides, the distribution of partial and clearcut harvesting, and 
whether clearcut stands are artificially regenerated (i.e., planted). 
In addition, we conducted additional sensitivity analysis to assess the 
impact of some of the core assumptions on our model estimates. The 
first sensitivity analysis evaluated the effect of climate change on 
forest growth and sequestration in the Landis model. In this case, we 
adjusted the climate change input files from RCP 2.6 to 8.5, which has 
a higher climate variability compared to historical trends. The set of 
sensitivity analyses that we conducted varied the harvest revenue, 
planting, and land acquisition costs to be +/^25% of the original 
assumption. Taking this approach allowed us to assess the relative 
importance of various input assumptions on the total and break-even 
costs of the different scenarios. Second, we conducted a sensitivity 
analysis that adjusted the stumpage price and planting costs that 
landowners may face under different stand and market conditions by a 
factor of R25% compared to our core assumptions.
2.3  Agriculture
2.3.1  Overview
    The agricultural sector in Maine emitted 0.38 million tons of 
CO2e (MtCO2e) in 2018, approximately 2% of total 
state emissions (17.51 MTCO2e) across all reported sectors 
(Maine DEP, 2020). A bulk of the emissions are from livestock (via 
enteric fermentation and manure management), with dairy contributing 
48% of the total agricultural sector emissions (Figure 6). Agriculture, 
excluding forestry, fishing, and aquaculture, encompasses 1.3 million 
acres (2017 Census of Agriculture, 2019), has an annual economic impact 
of $3.8 billion, supports 25,000 jobs, includes 8,000 farms, and 
represents about 5% of the state's GDP (Lopez, et al., 2014). The 
primary crops grown in Maine include potatoes, blueberries, hay, and 
grains including corn, barley, and oats. These crops represent 76% of 
the total harvested acreage in 2017. Dairy and other livestock 
commodities represent over 20% of farm sales (2017 Census of 
Agriculture, 2019). Although 90% of Maine is covered by forest, 
agriculture remains an important part of Maine's cultural identity, 
local economies, and current and future food security.
Figure 6. Maine Ag GHG Emissions (2017)


          Maine Agricultural GHG Emissions by major enterprise. Source: 
        DEP, 2020.
2.3.2  NCS Practices/Scenarios
    Despite representing a smaller sector of the Maine economy than 
forestry, changes to agricultural management practices can also 
contribute to state-wide climate change mitigation while enhancing 
adaptation and resilience in the agricultural sector. Agricultural 
natural climate solutions have been identified as an important strategy 
for improving farm viability by increasing carbon storage, limiting 
greenhouse gas emissions, improving soil health and water quality, and 
increasing farmer yields and profits per acre. NCS practices can be 
adopted by farmers with operations of all sizes and production methods. 
We analyzed a range of agricultural NCS that were already being 
implemented on some of Maine's farms or were determined to be feasible 
given Maine's climate and farming conditions. These practices are 
summarized in Table 2. Additional details are provided below and in 
Appendix B.

   Table 2. Overview of agricultural NCS practices considered for this
                                analysis
------------------------------------------------------------------------
      Practice                 Overview                Application
------------------------------------------------------------------------
                       Cropland and Grassland NCS
------------------------------------------------------------------------
Cover cropping        Permanently implement      potatoes, corn, other
                       cover cropping as part     grains, vegetables
                       of farm system for
                       enhanced soil organic
                       carbon accumulation;
                       reduce erosional soil
                       losses, enhance water
                       infiltration, reduce N
                       losses (N2O, NO3)
Intensive to reduced  Permanently switch to      potatoes, corn, other
 till                  reduced till farming       grains, vegetables
                       that is targeted on
                       shallow soil disturbance
                       to reduce C loss
Reduced to no-till    Permanently switch to no-  corn, other grains,
                       till farming for           vegetables
                       enhanced soil organic
                       carbon accumulation
                       through less disturbance
                       of the soil
Intensive to no-till  Permanently switch to no-  corn, other grains,
                       till farming for           vegetables
                       enhanced soil organic
                       carbon accumulation
                       through less disturbance
                       of the soil
Biochar amendment     5.9 t/ac biochar           potatoes, corn, other
                       broadcast applied to       grains, vegetables,
                       soil in year 1 of a 20     hay, blueberries,
                       year cycle for enhanced    apples
                       soil C sink, improved
                       soil health, reduced GHG
                       losses and nutrient
                       runoff
Manure amendment      Substitute fertilizer      potatoes, corn, other
                       with manure and compost    grains, vegetables,
                       for reduced CO2, CH4,      hay, blueberries,
                       and N2O losses             apples
Perennial set asides  Permanently convert crop   potatoes, corn, other
                       and pasture to no-         grains, vegetables,
                       harvest set aside          hay, fruit
                       grassland. Soil C
                       enhanced through reduced
                       disturbance
Riparian planting     Plant 35 buffer of trees,  potatoes, corn, other
                       shrubs, and grass along    grains, vegetables,
                       streams running along      hay, fruit
                       marginal cropland and
                       pasture
------------------------------------------------------------------------
                         Dairy Manure Management
------------------------------------------------------------------------
Large Complete Mix    CH4 emissions are reduced  1 digester per 2,500
 Anaerobic Digester    using a large model low-   cows
 with electricity      rate digester in which
 generation            digestate is actively
                       mixed in a heated tank
                       with airtight cover.
                       Digestate is gradually
                       displaced by incoming
                       manure substrate
Covered Lagoon/       Passive digester in which  1 digester per 300 cows
 Holding Pond          an impermeable cover and
 Anaerobic Digester    pipe system traps and
                       collects CH4 for reduced
                       emissions. Technology is
                       simple and well-
                       established, but
                       supplemental heat may be
                       needed in northern
                       climates
Soild-liquid          Process for separating     Active SLS with a
 separation (SLS)      dairy solids from          screen separator, 1
                       liquids, either to         SLS per 1,000 cows
                       reduce manure transit
                       costs and associated
                       emissions or as a pre-
                       treatment for anaerobic
                       digestion
Small Complete Mix    CH4 emissions are reduced  1 digester per 300 cows
 Anaerobic digester    using a small model low-
 (AD) with             rate digester in which
 electricity           digestate is actively
 generation            mixed in a heated tank
                       with airtight cover.
                       Digestate is gradually
                       displaced by incoming
                       manure substrate
Plug Flow Anaerobic   CH4 emissions are reduced  1 digester per 300 cows
 digester (AD) with    using a low-rate
 electricity           digester in which
 generation            incoming high-fiber
                       substrate displaces and
                       moves digestate through
                       the system, usually
                       without active mixing.
                       Consists of a long
                       heated tank with
                       airtight cover
------------------------------------------------------------------------

2.3.3  Analytical Approach
    The agricultural NCS modeling was centered on a financial and 
agronomic response analysis that quantified the economic impacts 
(revenue, cost, etc.) of implementing NCS relative to the change in 
yields, GHG emissions, and carbon sequestration relative to the 
business as usual (BAU) or baseline case over the next 20 years. In 
this analysis, the baseline assumed that current yields and areas were 
held constant over time.\3\ The NCS practices included cover crops, 
reduced-till, no-till, biochar amendments, amending soils with manure, 
manure management, and perennial set-asides (Table 3). GHG emissions 
factors and sequestration for the model baseline and NCS practices were 
based on an extensive literature review. Most baseline emissions 
factors were based on estimates from Poore and Nemecek (2018). Crop NCS 
mitigation factors were primarily estimated using the COMET Planner 
tool (Swan, et al., 2020), while dairy manure management factors were 
primarily derived from the EPA Ag Star Livestock Anaerobic Digester 
Database (EPA, 2020). All impacts were estimated at the major crop, NCS 
practice, and county-level. Most of the results in the main report are 
presented at the aggregate state level, while more detailed results are 
presented in Appendix B.
---------------------------------------------------------------------------
    \3\ Due to lack of data, we were unable to model the impact of 
climate change on crop yields.
---------------------------------------------------------------------------
    Baseline and current NCS practice area by major crop category in 
Maine (Table 3) were drawn or extrapolated from data provided in the 
2017 USDA NASS Census of Agriculture (2017 Census of Agriculture, 
2019). Baseline crop production area values were: 50,211 acres of 
harvested potato, 38,660 acres of lowbush blueberry, 175,231 acres of 
hay and haylage, 32,571 acres of corn grown for grain and silage, 
39,419 acres of other grains, 7,441 acres of apples and other perennial 
crops, and 12,028 acres of vegetables other than potato. In developing 
Table 3, several assumptions were made. All area currently in no-till 
production (21,676 acres) was assumed to be in silage or grain corn 
systems.\4\ Area in reduced tillage (31,953 acres) was split between 
potato, other vegetables, and other grains.\5\ Given uncertainty around 
the proportion of potato rotation crops reported as cover crops vs. 
small grains, we used the sum of harvested potatoes in the top three 
potato-producing counties (49,772 acres) as an estimate for cover crop 
adoption, assuming a 1:1 rotation.\6\ The area of other vegetable land 
in cover crops was assumed to be the total (55,462 acres) minus the 
amount in potato systems. The total value of other grains was assumed 
to be equivalent to additional cover crop land, since small grains 
often function as cover crops. We assumed that all annual systems could 
be transitioned to rotations that are more diverse than what is 
currently implemented and therefore we assigned starting values of 
zero.\7\ Current adoption of biochar amendments was assumed to be zero 
based on our understanding that this practice is uncommon at 
present.\8\ The acreage on which nitrogen fertility is offset with 
dairy manure amendment (74,943 acres) was split between corn and 
hayfields such that a large fraction of silage and grain corn (90%; 
29,314 acres) were assumed to have implemented this practice, with the 
remainder (45,629 acres) allocated to hay and haylage.\9\
---------------------------------------------------------------------------
    \4\ Informed by personal communication with E. Mallory and J. 
Jemison, Spring 2020.
    \5\ Definitions of reduced tillage vary by system and may not align 
perfectly with the NRCS definition. Based on data from an organic 
vegetable farmer focus group (N. Lounsbury, unpublished data, February 
26, 2020) we assumed a large fraction of vegetable land (50%; 6,104 
acres) is employing some form of reduced tillage. The potato acreage 
employing a reduced tillage practice such as one-pass hilling was 
estimated by adding the area of potatoes harvested in the top three 
potato-producing counties assuming a 1:1 rotation (99,544 acres) and 
subtracting the total land in intensive production in these counties 
(81,030 acres) to arrive at 18,514 acres. The 13,439 reduced tillage 
acres remaining from the statewide total was assigned to other grains.
    \6\ Informed by data from potato farmer focus group (N. Lounsbury, 
unpublished data, January 23, 2020) indicating this rotation is common.
    \7\ The meaning of `diverse rotations' varies by system and can 
overlap with cover crop adoption.
    \8\ N. Lounsbury, unpublished data, January 23, 2020; S. O'Brien, 
unpublished data, Fall 2019.
    \9\ Though many diversified vegetable farms also utilize manure as 
a soil amendment, this use was excluded from the present analysis, 
which assumed on-farm use of manure for forage and feed production by 
commercial dairies.

                       Table 3. Estimated Baseline Area in NCS Practices for Maine (acres)
----------------------------------------------------------------------------------------------------------------
                                                                                             Convert
                 Total                Reduced     Cover     Diverse    Biochar    Amend w/      to      Riparian
  Major Crop      Crop     No-till    tillage      crop    rotations    Amend      manure   perennial    Buffer
                 Area*                                                                      set-aside
----------------------------------------------------------------------------------------------------------------
Potato            50,211          X     18,514     49,772          0          0          0          0          0
Lowbush           38,660          X          X          0          X          0          X          X          0
 blueberry
Hay & haylage    175,231          X          X          X          X          0     45,629          X          0
Silage &          32,571     21,676          0          0          0          0     29,314          0          0
 grain corn
Other grains      39,419          0     13,439     39,419          0          0          0          0          0
Apples &           7,441          X          X          X          X          0          X          X          0
 other
 perennials
Other             12,028          0      6,014      5,690          0          0          X          0          0
 vegetables
              --------------------------------------------------------------------------------------------------
  Total Study    355,561     21,676     37,967     94,881          0          0     74,943          0          0
   Area
----------------------------------------------------------------------------------------------------------------
* = not all crop area is currently in a NCS practice; More than 1 practice can be implemented on a given acre
  (e.g., no-till and cover crop); X = not eligible for NCS practice.

2.3.4 Agricultural enterprises
    The following section briefly describes the farm systems that we 
included in our analysis. We constructed representative cost budgets 
for the primary crops grown in Maine based on enterprise farm budgets 
for Maine or New England and expert consultation. Table 4 summarizes 
the per acre yield, price, revenue, and cost for each agricultural 
enterprise as well as net revenue and net GHG emissions. Price per unit 
was estimated from a five year average of the commodity's price in 
Maine from 2012-2017 (Crop Values Annual Summary, 2020). Detailed 
budgets and accompanying assumptions are included in Appendix B. The 
methodology and estimates for calculating net GHG emissions are also 
explained in Appendix B.

             Table 4. Key Maine agricultural enterprises baseline farm financial and GHG input data.
----------------------------------------------------------------------------------------------------------------
                    Yield
   Enterprise     (unit/ac/  Price  ($/unit)  Revenue  ($/ac/  Cost  ($/ac/yr)  Net Revenue  ($/ Net GHG (tCO2e/
                     yr)                            yr)                              ac/yr)           ac/yr)
----------------------------------------------------------------------------------------------------------------
Hay              6 tons                 $165             $992             $323             $670                0
Potato           240 cwt                 $10           $2,510           $1,382           $1,129             2.11
Blueberries      4,445                 $0.47           $2,102           $1,504             $598             0.32
                  pounds
Wheat            45 bushels              $19             $844             $312             $532             1.03
Corn             100                      $4             $369             $574            ^$205             1.21
                  bushels
Barley           48 bushels               $5             $233             $373            ^$139             0.18
Vegetables       varies               varies          $22,117          $17,276           $4,841             1.58
Apples           30,244                $0.31           $8,196           $5,966           $2,230             2.24
                  pounds
Dairy            158 cwt                 $23           $3,567           $4,442            ^$875             6.19
----------------------------------------------------------------------------------------------------------------

    Apples

    There are 449 farms with apple orchards in Maine covering 2,668 
acres. 38% of these orchards are smaller than one acre, and another 39% 
are between one and five acres in size (2017 Census of Agriculture, 
2019). Soil amendments with biochar and manure are NCS practices that 
can be implemented in orchards. We estimated that, on average, a 
typical apple system made $8,196/bearing-fruit-acre (bfa) in revenue 
and had $5,966/bfa in total costs. As a result, the system produced 
$2230/bfa in net revenue per year. Additional information about the 
apple system is available in Appendix B.

    Blueberries

    Approximately 60,000-65,000 acres of farmland in Maine are in wild 
or lowbush blueberry production, of which 850 acres are certified 
organic. Blueberries have a 2 year production cycle such that 
approximately half of this total acreage is harvested per annum. 
Between 66 and 70 million pounds of blueberries are produced annually 
in Maine (Drummond, et al., 2009; Rose, et al., 2013). Blueberry 
pricing has been a challenge for the industry in some recent years, 
with wholesale prices for conventional blueberries falling between 
$0.27-$0.75/lb between 2012 and 2018 (Calderwood & Yarborough, 2019). 
We estimated that an average blueberry system made $2,102/ac in revenue 
and had $1,504/ac in total costs. As a result, the system produced an 
average of $598/ac in net revenue per year. Additional information 
about the blueberry system is available in Appendix B.

    Dairy

    There are approximately 450 farms with dairy cows in Maine, a 
majority of which have herd sizes <50 cows. The current 218 commercial-
scale dairy farms house an estimated 28,000 cows.\10\ Economic risks 
from market price fluctuations are offset for conventional dairies 
through the ``tier program[''] (Drake, 2011), while pricing for organic 
milk is usually set in advance by 2-3 year contracts. About 30% of 
Maine dairy farmers are certified organic, with organic milk making up 
7% of milk volume produced. Dairy cows are fed a roughage-based diet of 
forage, hay, and corn silage which is generally locally produced. In 
addition, grazing is common during the summer, and diets may be 
supplemented with concentrate. While manure represents a resource that 
can be used as part of integrated farm systems, storage during winter 
and mud season is a necessity. Land access is a major limiting factor 
to dairy production in Maine, in part because lack of contiguous fields 
raises costs of manure transport.\11\ We estimated that, on average, a 
typical dairy farm made $3,567/cow in revenue and had $4,442/cow in 
total costs. As a result, the system produced ^$875/ac in net revenue 
per year for the 2012-2017 timeframe.\12\ Additional information about 
the dairy system is available in Appendix B.
---------------------------------------------------------------------------
    \10\ R. Kersbergen, personal communication, Spring 2020.
    \11\ R. Kersbergen, personal communication, Spring 2018.
    \12\ N.B., the negative net revenue for dairy over the 5 year 
period of our data maybe due to milk prices being lower than average 
over a longer historical period and/or the set of fixed costs that we 
accounted for, which may not be relevant for all Maine dairy farms.

---------------------------------------------------------------------------
    Grains (barley, corn, and wheat)

    Several types of grains, including grain and silage corn, barley, 
and wheat, are grown in Maine. These crops are primarily grown as feed 
for livestock and/or as part of rotational cropping systems. Several 
NCS practices can be implemented for grains, including no-till, reduced 
tillage, cover crops, and soil amendments. We estimated that, on 
average, the net revenue for barley, corn silage, and wheat were ^$139/
ac, ^$205/ac, and $532/ac, respectively. When coupled with a dairy 
farm, the negative net revenue per acre for barley and corn silage can 
be offset as feed for livestock. Acting as rotation crops in a potato 
system, barley and wheat function similarly to cover crops, requiring 
less intensive management and allowing soils to `rest.' Additional 
information about each of these grain systems is available in Appendix 
B.

    Hay

    According to USDA NASS, 174,000 acres of farmland in Maine are used 
for forage, including hay (2017 Census of Agriculture, 2019). Most 
hayfields are perennial sods consisting of clovers and grasses 
including bluegrass, orchard grass, quackgrass, and timothy. Periodic 
additions of lime are needed to reduce acidity, helping to manage weeds 
and maintain hayfield productivity (Kersbergen, 2004). More intensive 
management of hayfields including occasional tillage and re-seeding of 
desired species, as well as fertility applications, is also common for 
some applications (Hall, 2003). Hayfields are inherently no- or low-
tillage production systems. Additional NCS practices that might be 
applicable in managed hayfields include strategic integration of 
organic amendments including manure or biochar into production. We 
estimated that, on average, a typical hayfield system made $992/ac in 
revenue and had $191/ac in variable costs and $132/ac in annualized 
fixed costs. As a result, the system produced $670/ac in net revenue 
per year. Additional information about the hay system is available in 
Appendix B.

    Potato

    Potatoes are a high-value crop, but also expensive to grow.\13\ 
Approximately 50,000 acres of potatoes in Maine were grown in 2017 
(2017 Census of Agriculture, 2019) for three key markets: processing 
(30,000 acres), seed (11,000 acres), and tablestock (9,000 
acres).\14\ Most growers are using a 1:1 rotation with one year of 
potatoes and one year of a much less valuable cash crop like a grain, 
or an unharvested cover crop. Some growers are using a 2:1 rotation 
with a longer ``off'' period from potatoes.\15\ Potato cropping 
involves key vulnerable periods with respect to potential soil erosion 
and loss of organic matter. The multiple tillage/cultivation passes 
inherent to potato planting and hilling are harmful for soil organic 
matter retention and soil structure. Despite the adoption of one-pass 
hilling by some growers, potato cropping systems remain by necessity 
tillage-intensive. We estimated that, on average, a typical potato 
system made $2,510/ac in revenue and had $1,035/ac in variable costs 
and $347/ac in annualized fixed costs. As a result, the system produced 
$1,129/ac in net revenue per year. Additional information about the 
potato system is available in Appendix B.
---------------------------------------------------------------------------
    \13\ J. Jemison, personal communication, February 2018.
    \14\ J. Jemison, personal communication, February 2018.
    \15\ N. Lounsbury, unpublished data, January 23, 2020.

---------------------------------------------------------------------------
    Diversified vegetable farm

    This farm type is by nature diverse, often growing a wide variety 
of crops in complex multi-year rotations. According to USDA NASS data 
there were 881 Maine farms growing fresh market vegetables (not 
including potato farms) harvested for sale in 2017. Some of the 
prevalent crops are snap beans, potatoes, peppers, squash, sweet corn, 
and tomatoes (2017 Census of Agriculture, 2019). Diversified vegetable 
systems usually rely on regular tillage, both for weed control and 
preparation of a seedbed for planting (Myers, 2008). However, reduced-
till practices are possible and of interest to growers, so reduced-till 
and perhaps adoption of no-till in some cropping sequences represent 
possible NCS. Cover cropping is utilized by many diversified vegetable 
farmers at present, but their use of the practice is sometimes 
constrained by limited acreage and the opportunity cost of taking land 
out of production.\16\ Further adoption or increased intensity of cover 
cropping is likely feasible in these systems with altered incentive 
programs. We estimated that, on average, a typical diversified 
vegetable system made $22,117/ac in revenue and had $11,724/ac in 
variable costs and $5,552/ac in annualized fixed costs. As a result, 
the system produced $10,394/ac in net revenue per year. Additional 
information about the diversified vegetable system is available in 
Appendix B.
---------------------------------------------------------------------------
    \16\ R. Clements, unpublished data, 2019.
---------------------------------------------------------------------------
2.3.5  NCS Mitigation costs and effectiveness by practice
    Each NCS practice was assessed for its ability to reduce GHG 
emissions from Maine agriculture, as well as the cost that it might 
take to do so. The costs of each NCS practice were based on a mix of 
yield and revenue changes, capital expenditures, operating costs, and 
land rental rates. Periodic costs such as capital equipment or land 
acquisition were annualized over the study period (20 years) using a 
discount rate of 5% so that they could be directly compared with annual 
costs. More details on the sources of these costs are provided in 
Appendix B.
2.3.6  Sensitivity Analysis
    The Maine agriculture NCS practice model is dependent on a range of 
assumptions that varied in our literature review. These include the 
impact of practices on crop yields, farm revenue, and implementation 
costs. As a result, we conducted a sensitivity analysis where we use 
low, medium (core), and high parameter values for each of these key 
input assumptions. This approach allowed us to assess the relative 
influence of each parameter on the key model estimates, namely total 
mitigation cost and break-even carbon price for each practice. Note 
that we opted to exclude sensitivity of GHG mitigation factors from 
this analysis due to the wide variation in max and min estimates. 
Furthermore, we did not analyze the effect of climate change on crop 
yields and mitigation potential due to lack of data.
3. Results
3.1  Forestry
3.1.1  Model Baseline
    Circa 2010, LANDIS-II estimates based on initial forest conditions 
indicated there was approximately 1.33 Tg of aboveground carbon 
distributed broadly across our study area (Figure 7). At the cell-
level, aboveground carbon ranged from 116-7,976 g m-2, with 
an average of 4,250 gm-2, reflecting complex variation in 
tree species relative abundance and forest age across northern Maine.
Figure 7. Total Aboveground Carbon ca. 2010 gm-2


          Spatial distribution of total aboveground carbon ca. 2010, 
        also representing the starting conditions for forest landscape 
        simulations 2010-2070.

    Under the baseline (i.e., BAU min50 under RCP 2.6) scenario total 
aboveground carbon declined 7%, from approximately 1.33 Tg to 1.24 Tg, 
between 2010 and 2070 (Figure 8). On average 0.27 Tg of aboveground 
carbon was projected to be harvested every 10 years. The average total 
harvest footprint every 10 years was projected to be 1,486,963 acres, 
which translated into an annual harvest rate of approximately 1.7% for 
the study area.
Figure 8. 


          Total, live aboveground million metric tons of carbon (MMTC) 
        (standing; dashed line) and total harvested MMTC (gray bars) 
        every 10 years (e.g., 2010-2020, 2020-2030, etc.) under the 
        baseline or Business-as-usual (BAU) scenario, 2010-2070.

    Harvest levels in the 9.1 m acres of northern Maine tracked in the 
Landis model were estimated to be maintained around 9.3 million green 
tons per year, which is consistent with trends over the past 10 years. 
These harvests were expected to be a similar mix of sawlogs, pulpwood 
and low-diameter biomass that were converted into the relevant forest 
products, again matching historical trends. As a result, the BAU 
harvest of about 145,000 acres each year--of which 90% was partial 
harvest--was estimated to accrue $120 million/yr in stumpage revenue. 
These estimates were the values for which all the other Landis-based 
scenarios were compared against in this study.
3.1.2  Forest NCS practice results
    3.1.2.1  Forest management in Landis

    Total aboveground carbon followed a wide variety of trends, 
including increasing and declining, under RCP 2.6 and the different 
management scenarios (Figure 9). In general, total aboveground carbon 
was lower than the initial amount under the extended rotation 
scenarios, with the exception of the Min 100 years, which was the only 
scenario that projected a reversal in direction (rapidly increasing 
until 2040 and then rapidly declining). Increased clearcutting also 
resulted in a declining trend unless paired with planting. A set-aside 
resulted in a relatively stable aboveground carbon pool at 10%, or 
slightly increasing at 20%. Circa 2070, all scenarios were higher than 
BAU min50, ranging from +1% (35% clearcut) to +40% (50% clearcut, plant 
or 35% clearcut, plant, 20% set-aside).



          Comparison of total aboveground carbon stock (MMTC) under RCP 
        2.6 and the different forest management scenarios 2010-2070. 
        See Table 1 for scenario descriptions.

    Converting the aboveground and harvested carbon into annual figures 
allows us to estimate the annual change in carbon sequestration over 
different time periods, as well as the cost of doing so relative to the 
BAU (typically in the form of lost revenues or increased planting and 
management costs). Figure 10 indicates that extending the minimum stand 
age before harvest out to 100 years increased forest carbon over the 
first 20 years as many stands that were harvested under BAU were left 
to mature. However, those increases in carbon diminish over time as the 
same stands were then harvested between 2040 and 2070. In contrast, 
stands that involved active planting and/or set-asides continued to 
sequester carbon on a steady basis over the next 50 years. We estimated 
that simply clearcutting stands but not artificially regenerating them 
produced minimal carbon gains above the BAU case.
    Adjusting management to have longer rotations or 20% of total 
forest area established as no-harvest set asides resulted in a 
noticeable reduction in timber harvests (13-17% below BAU) over the 
next 50 years (Figure 11). All other scenarios projected changes of 8% 
or less. This finding suggests that for many of the proposed forest 
management options, it is possible to increase forest (and harvested 
wood product) carbon while simultaneously maintaining a consistent 
timber supply that is close to historical levels. Furthermore, the 
ability to maintain timber supply across the landscape suggests that 
there could be minimal `leakage' of forest carbon loss to other parts 
of the globe as a result of implementing forest NCS in Maine.
Figure 10. Mean Annual Forest + Product Carbon Baseline
(tCO2e/yr)


          Mean annual forest and harvested wood product carbon change 
        from BAU.
Figure 11. Mean Harvest Volume
(gt/yr)


          Mean annual timber harvest volume.

    The modeled scenarios indicate changes in total timber harvests 
(and revenue) coupled with increased costs associated with the planting 
scenarios will result in overall total costs for implementing these NCS 
relative to the BAU (Figure 12). The 100min scenario accrued the most 
costs over the first 20 years due to high opportunity costs associated 
with reduced harvests. When the analysis was extended to 50 years, 
scenarios that involved planting faced the highest costs. Of course, 
those higher costs resulted in greater amounts of carbon being 
sequestered on the stump and harvested wood products, thereby reducing 
the break-even carbon price that a landowner may be willing to receive 
to implement a specific practice (Figure 13). When assessing the GHG 
mitigation cost from this perspective, it is clear that most forest 
management NCS practices can be implemented at a cost of $10-20/
tCO2e, which is relatively inexpensive compared to most non-
NCS opportunities.
Figure 12. Mean Cost Relative to Baseline
($/yr)


          Mean total annual mitigation cost relative to BAU.
Figure 13. Mean Break Even Carbon Price
($/tCO2e)


    While our results are largely presented at the nine million acre 
study level, the Landis-modeling framework also allows one to assess 
impacts at a species and habitat level. Some of these aspects are 
summarized in Table 5. As presented above, total timber harvest was 
lower under all forest management scenarios relative to the baseline 
(BAU min50) 2010-2060, ranging from less than 0.5% lower under the 35% 
clearcut with or without planting to 13% lower under extended rotation 
to a minimum age of 100 years. However, the forest management scenarios 
varied widely in the impact on the ecosystem services we considered. 
Spruce-fir carbon increased under all scenarios, except 35% clearcut 
without planting. As with total aboveground carbon, planting after 
clearcutting increased spruce-fir carbon. Late successional (LS) forest 
for both spruce-fir (SF) and northern hardwood (NH) forest declined 
under Min 100 but increased with the addition of a 10% forest set-
aside. LS results under the 35% clearcut scenarios varied, but lynx 
foraging habitat increased under all three. Lynx habitat decreased with 
extended rotation (Min 100) or 10% forest set-aside.

 Table 5. Comparison of select forest NCS model outputs ca. 2060 under a subset of forest management strategies
  and RCP 2.6, including mean break even carbon price, and relative difference (compared to BAU min50) in total
    harvest, spruce-fir total aboveground carbon, late successional spruce-fir (SF) or northern hardwood (NH)
                                       forest, and lynx foraging habitat.
----------------------------------------------------------------------------------------------------------------
                               Break even       Total                        LS forest Change           Lynx
          Scenario            carbon price  harvest 2010- Spruce-Fir C ----------------------------    habitat
                                 ($/tCO2)       2060                         SF            NH          Change
----------------------------------------------------------------------------------------------------------------
              Min 100 years            $12          ^13%           33%           ^8%          ^13%          ^25%
              10% set-aside            $20           ^7%           10%            4%            4%           ^3%
                     35% CC             $6         ^0.4%           ^4%          ^12%            4%           33%
             35% CC + plant            $14         ^0.3%          117%            9%           ^7%          487%
  35% CC + plant + 10% set-            $12           ^8%          118%           ^4%            0%          427%
                       aside
----------------------------------------------------------------------------------------------------------------

    3.1.2.2  Afforestation and avoided conversion

    As discussed above, the afforestation and avoided forest conversion 
estimates were derived outside of the Landis model and encompass the 
entire State of Maine. Afforestation and restoration of areas that were 
determined to be forested historically, but not reduce agricultural 
production or low to high intensity development was estimated to be 
feasible on about 360,000 acres of land across the state (Cook-Patten, 
et al., 2020). The average afforested stand was estimated to sequester 
2.1 tCO2e/ac/yr, thereby yielding a total of 760,000 
tCO2e/yr in additional carbon sequestration. Implementing 
this NCS across Maine was estimated to cost about $22.8 million/yr, or 
$30/tCO2e.
    Incentivizing forest landowners to avoid converting their land to 
other uses has a wide range of costs depending on where the forest 
under threat is located in the state and what it is expected to be 
converted to. Following the historical trend that about 2,000 acres per 
year of forest is converted to agriculture in the state, we estimated 
that this could be avoided at a cost of about $21/tCO2e, 
thereby sequestering an average of 200,000 tCO2e/yr over the 
next 50 years. The cost of avoided conversion to developed land was 
much higher due to the expected land value associated with that land 
use. As a result, it could cost about $700/tCO2e to keep the 
6,500 acres of forest threatened by development every year as forests 
in perpetuity.\17\ If there was a willingness to pay this amount, then 
about 685,000 tCO2e/yr could be sequestered on average over 
the next 50 years by these `protected' areas.
---------------------------------------------------------------------------
    \17\ N.B., because an additional 8,500 acres of `new' land is 
threatened by conversion each year, the total amount of land that needs 
to be protected increases over time. As a result, over 420,000 acres of 
forest area could potentially be spared from conversion under this 
approach by 2070.

---------------------------------------------------------------------------
    3.1.2.3  Summary of core modeled results

    The 50 year average estimates of key results from all the forest 
NCS practices evaluated are summarized in Figure 14. The figure shows 
that many of the top mitigation options are expected to come from 
increasing clearcuts and planting and/or permanent set-asides. In 
addition, afforesting marginal pasture and cropland could also provide 
additional mitigation in addition to the improved forest management. We 
find that the average break-even carbon prices for most forest NCS 
practices are in the range of $10-$20/tCO2e. Additionally, 
if landowners could collectively change forest management across the 
9.1 million acres in northern Maine from BAU to 50% clearcut followed 
by planting in addition to afforesting marginal land and reducing 
conversion of forests to cropland across the state, we estimate that it 
could yield about 4.5 MtCO2e/yr in additional carbon 
sequestration at a cost of $64 million/yr or $14/tCO2e.
Figure 14. Total Maine Forest NCS Mitigation
(tCO2e/yr)


          Total Maine forest NCS mitigation potential 
        (tCO2e/yr), 2020-2070 annual average, RCP 2.6.
          (Note: the avoided conversion and afforestation scenarios 
        cover the entire state, while the other scenarios only include 
        9.1 million acres of managed forest in northern Maine.)
3.1.3  Sensitivity Analysis
    3.1.3.1  Climate change impacts sensitivity

    Total forest carbon was generally higher under the high emission 
scenario (RCP 8.5) across all management scenarios, until 2050 (Figure 
15). Beginning with the 2050-2060 interval (blue bar, Figure 15), there 
was a reversal in trends under RCP 8.5 that resulted in a negative net 
difference between RCP 8.5 and RCP 2.6. Across all scenarios, this 
difference increased 2060-2070 (dark blue bar, Figure 15).
Figure 15.


          Difference in MMTC, across scenarios, for aboveground carbon 
        per interval between RCP 8.5 and RCP 2.6. A positive difference 
        indicates that total forest carbon stock was higher in a given 
        interval (e.g., 2010-2020) under RCP 8.5.

    Table 6 summarizes the key differences between RCP 2.6 and RCP 8.5 
estimates based on a 50 year annual mean over 2020-2050. The analysis 
indicates that the most sensitive indicators are total forest carbon 
and total mitigation cost. Scenarios that specified more clearcuts and/
or planting appear to be more sensitive to climate impacts, which makes 
sense as this approach accelerates forest succession. Mean harvest 
volume only differed by 1% between the two RCPs, which was by design in 
our modeling exercise.

                               Table 6. Key RCP 8.5 model estimates and difference from RCP 2.6 scenarios, 2020-2070 mean.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                    Total Forest Carbon Above      Total Harvest  (gt/yr)        Total Cost  (mil $/yr)     Break-even carbon price  ($/
                                      Baseline  (tCO2e/yr)     ------------------------------------------------------------            tCO2e)
            Scenario             ------------------------------                                                            -----------------------------
                                     RCP 8.5         % Diff        RCP 8.5         % Diff        RCP 8.5         % Diff        RCP 8.5         % Diff
--------------------------------------------------------------------------------------------------------------------------------------------------------
                  Min 85 years         ^12,935           ^29%      9,573,938             1%          ^$1.8            ^4%            $15            ^2%
                 Min 100 years         856,688             3%      8,189,758             1%          $16.6             2%            $12             0%
             35% Clearcut (CC)         ^66,115            ^5%      9,388,191             1%           $0.6            18%             $6            ^5%
             50% Clearcut (CC)         170,936             3%      8,986,382             1%           $6.0             1%            $10            ^6%
                 35% CC, plant       2,290,789            ^7%      9,397,854             1%          $24.2             0%            $11             3%
                 50% CC, plant       3,317,819            ^6%      9,006,471             1%          $37.3             0%            $11             3%
                 10% set-aside         501,816             2%      8,746,120             1%           $9.2             2%            $19            ^1%
                 20% set-aside       1,315,509            13%      7,728,575             0%          $22.7             7%            $19            ^5%
  35% CC, plant, 10% set aside       2,631,673            ^5%      8,718,366             1%          $31.6             1%            $12             4%
  35% CC, plant, 20% set aside       3,073,542            ^4%      7,795,875             1%          $41.6             1%            $14             4%
                 Afforestation         735,443             0%      9,264,829             1%          $22.1             0%            $30             0%
      Avoided Conversion--Crop         100,086             0%      9,264,829             1%           $2.1             0%            $21             0%
 Avoided Conversion--Developed         341,358             0%      9,264,829             1%         $239.9             0%           $703             0%
--------------------------------------------------------------------------------------------------------------------------------------------------------

    3.1.3.2  Economic benefits and costs sensitivity

    The revenue and costs associated with timber harvests and planting 
can vary over time and space. As a result, we conducted a sensitivity 
analysis that adjusted the stumpage price and planting costs that 
landowners may face under different stand and market conditions by a 
factor of R25% compared to our core assumptions. As expected, changing 
stumpage prices had a linear effect on total cost and breakeven carbon 
prices for all scenarios that did not involve planting (Table 7). On 
the contrary, low/high stumpage prices had a relatively lower impact on 
costs for scenarios that also included planting. This is because 
planting trees contributes to a relatively large part of the total cost 
incurred by forests undertaking that practice. This finding is 
confirmed with the planting cost sensitivity analysis, which estimated 
that adjusting planting costs by 25% could lead to a 12% to 25% change 
in total costs in implementing those management practices.

                          Table 7. Change in forest NCS mitigation costs for stumpage price and planting sensitivity analysis.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                               Total Cost (Mil $/yr)                                     Break-even carbon price ($/tCO2e)
        Scenario         -------------------------------------------------------------------------------------------------------------------------------
                           Low Planting    High Planting   Low Stumpage    High Stumpage   Low Planting    High Planting   Low Stumpage    High Stumpage
--------------------------------------------------------------------------------------------------------------------------------------------------------
          Min 85 years               0%              0%            ^25%             25%              0%              0%            ^25%             25%
         Min 100 years               0%              0%            ^25%             25%              0%              0%            ^25%             25%
     35% Clearcut (CC)               0%              0%            ^25%             25%              0%              0%            ^25%             25%
     50% Clearcut (CC)               0%              0%            ^25%             25%              0%              0%            ^25%             25%
         35% CC, plant             ^25%             25%              0%              0%            ^23%             23%             ^2%              2%
         50% CC, plant             ^21%             21%             ^4%              4%            ^21%             21%             ^4%              4%
         10% set-aside               0%              0%            ^25%             25%              0%              0%            ^25%             25%
         20% set-aside               0%              0%            ^25%             25%              0%              0%            ^25%             25%
35% CC, plant, 10% set-            ^18%             18%             ^7%              7%            ^17%             17%             ^8%              8%
                 aside
35% CC, plant, 20% set-            ^12%             12%            ^13%             13%            ^12%             12%            ^13%             13%
                 aside
         Afforestation             ^33%             33%            ^33%             33%            ^33%             33%            ^33%             33%
Avoided Conversion--Crop             0%              0%              0%              0%              0%              0%              0%              0%
Avoided Conversion--Dev.             0%              0%              0%              0%              0%              0%              0%              0%
--------------------------------------------------------------------------------------------------------------------------------------------------------

3.2  Agriculture
3.2.1  Model Baseline
    The agricultural sector model baseline estimates are listed in 
Table 8. We estimated that the 355,561 acres of major crops and 30,443 
head of dairy cattle in the state collectively produced about $850 
million in revenue per year, or about $246 million/yr in net revenue 
(i.e., profit) once you take into account capital and operating 
expenses. These baseline farm enterprises emitted about 320,000 
tCO2e/yr of GHGs, but also sequestered about 42,000 
tCO2e/yr through activities such as no till and cover 
cropping.

                        Table 8. Key Maine agricultural sector model baseline estimates.
----------------------------------------------------------------------------------------------------------------
                         Area
                       (acres)/     Revenue     Cost  (Mil      Net       Gross GHG       Carbon       Net GHG
        Crop             Head      (Mil $/yr)     $/yr)       Revenue     (tCO2e/yr)  Sequestration   (tCO2e/yr)
                       (cattle)                              (Mil $/yr)                 (tCO2e/yr)
----------------------------------------------------------------------------------------------------------------
               Hay       175,231       $173.9        $56.5       $117.4            0         7,072        ^7,072
            Potato        50,211       $126.0        $69.4        $56.7       20,184        10,801         9,382
       Blueberries        38,660        $81.3        $58.1        $23.1       12,513             0        12,513
             Wheat        19,710        $16.6         $6.2        $10.5       20,445         4,220        16,225
              Corn        32,571        $12.0        $18.7        ^$6.7       39,297        14,406        24,891
            Barley        19,710         $4.6         $7.3        ^$2.7        3,625         4,220          ^594
        Vegetables        12,028       $266.0       $207.8        $58.2       18,998         1,626        17,373
            Apples         7,441        $61.0        $44.4        $16.6       16,622             0        16,622
                    --------------------------------------------------------------------------------------------
  Crop Total.......      355,561       $741.5       $468.4       $273.0      131,685        42,345        89,340
                    --------------------------------------------------------------------------------------------
  Dairy............       30,443       $108.6       $135.2       ^$26.6      188,442             0       188,442
                    ============================================================================================
    Major Ag Sector      355,561       $850.1       $603.6       $246.4      320,127        42,345       277,782
     Total.........
----------------------------------------------------------------------------------------------------------------

    The baseline Maine agricultural sector GHGs and carbon 
sequestration are shown in Figure 16. When adding the 67,000 
tCO2e/yr of non-dairy livestock emissions to our estimates 
in Table 8, we estimated that gross GHGs are equal to about 387,127 
tCO2e/yr, while carbon sequestration from current NCS 
practices reduced the sector footprint by 42,345. For comparison, DEP 
(2020) estimates Maine's 2017 agricultural sector gross GHG emissions 
to be 380,000, or just 2% lower than our gross GHG estimate.
Figure 16. 


          Maine DEP (2020) and modeled baseline agricultural sector GHG 
        emissions.
3.2.2  Agriculture NCS practice results
    Applying our core (i.e., `medium') agricultural sector model 
assumptions about mitigation potential, yield change, and practice 
costs, we estimate that there is wide variation in potential from 
implementing agricultural NCS in Maine (Figure 17). According to our 
results, the largest mitigation potential comes from the application of 
biochar, which could yield nearly 570,000 tCO2e/yr, followed 
by permanent conversion from managed cropland and pasture to non-
harvested perennial grass (363,255 tCO2e/yr). Both of these 
could be implemented at relatively low cost as well, in the range of 
$25-$34/tCO2e (Table 9). The large mitigation potential is 
primarily a factor of two things. First, both of these practices have 
relatively high per acre carbon sequestration rates. Second, the two 
NCS practices apply to a wide range of crops, including hay, which 
makes up a large proportion of Maine's total crop area.
    Many of the other practices considered for this study yielded 
relatively low total mitigation or were relatively costly. Cover crops 
and reduced intensity tillage practices yielded between 13,423 and 
32,755 tCO2e/yr due to low area applicability and low rates 
of carbon accumulation (0.1 to 0.4 t/ac/yr) on a per acre basis. 
However, we note that our study only focused on the climate mitigation 
and yield impacts of implementing these practices, while they are 
likely to produce additional co-benefits such as improved soil health 
and water quality.
Figure 17. Total Maine Agriculture NCS Mitigation
(tCO2e/yr)


          Total Maine agriculture NCS mitigation potential 
        (tCO2e/yr).

    The Maine agricultural NCS model estimates by specific crop are 
summarized in Table 9. This table highlights how the overall carbon 
sequestration potential of some agricultural management practices is 
limited by the small amount of land in crop production. Furthermore, it 
highlights that mitigation has the potential to come from a wide range 
of crops.

                                               Table 9. Maine agricultural NCS practice estimates by crop.
--------------------------------------------------------------------------------------------------------------------------------------------------------
       NCS Practice             Hay         Potato     Blueberry      Wheat         Corn        Barley       Veg.       Apples       Dairy       Total
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Annual Mitigation (tCO2e/yr)
--------------------------------------------------------------------------------------------------------------------------------------------------------
  No-till from Intensive             0            0            0        8,968       14,820        8,968            0           0           0      32,755
    No-till from Reduced             0            0            0        6,997            0        6,997            0           0           0      13,994
         Reduced tillage             0        5,021            0        1,971        3,257        1,971        1,203           0           0      13,423
 Cover Crops--non-legume             0        6,527            0        2,562        4,234        2,562        1,564           0           0      17,450
     Cover Crops--legume             0       11,549            0        4,533        7,491        4,533        2,766           0           0      30,873
      Cover Crops--mixed             0        9,038            0        3,548        5,863        3,548        2,165           0           0      24,161
                 Biochar       280,370       80,338       61,856       31,535       52,114       31,535       19,245      11,906           0     568,898
          Amend w/Manure        27,161        7,783        5,992        3,055        5,049        3,055        1,864       1,153           0      55,112
    Convert to Perennial       225,224       42,545            0       22,961       40,700       14,552       17,273           0           0     363,255
 Dairy Manure Management             0            0            0            0            0            0            0           0     119,139     119,139
         Riparian Buffer        28,789        5,302        0 476        1,629          384          836            0           0      37,418
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Annual Mitigation Cost (Mil $/yr)
--------------------------------------------------------------------------------------------------------------------------------------------------------
  No-till from Intensive          $0.0         $0.0         $0.0         $1.7         $0.6         $0.7         $0.0        $0.0        $0.0        $3.0
    No-till from Reduced          $0.0         $0.0         $0.0         $1.7         $0.0         $0.7         $0.0        $0.0        $0.0        $2.4
         Reduced tillage          $0.0         $1.1         $0.0        ^$0.1         $0.6         $0.5         $0.3        $0.0        $0.0        $2.3
 Cover Crops--non-legume          $0.0         $3.2         $0.0         $2.8         $1.8         $1.6         $0.8        $0.0        $0.0       $10.0
     Cover Crops--legume          $0.0         $3.2         $0.0         $1.3         $1.4         $1.3         $0.8        $0.0        $0.0        $7.9
      Cover Crops--mixed          $0.0         $3.7         $0.0         $2.3         $2.0         $1.6         $0.9        $0.0        $0.0       $10.5
                 Biochar          $7.1         $2.0         $1.6         $0.8         $1.3         $0.8         $0.5        $0.3        $0.0       $14.5
          Amend w/Manure          $2.4         $0.7         $0.5         $0.3         $0.4         $0.3         $0.2        $0.1        $0.0        $4.9
    Convert to Perennial          $7.7         $1.8         $0.0         $0.7         $1.1         $0.7         $0.4        $0.0        $0.0       $12.4
 Dairy Manure Management          $0.0         $0.0         $0.0         $0.0         $0.0         $0.0         $0.0        $0.0        $2.6        $2.6
         Riparian Buffer          $3.6         $0.7         $0.0         $0.1         $0.2         $0.1         $0.1        $0.0        $0.0        $4.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Break-even Carbon Price ($/tCO2e)
--------------------------------------------------------------------------------------------------------------------------------------------------------
  No-till from Intensive            $0           $0           $0         $189          $41          $73           $0          $0          $0         $90
    No-till from Reduced            $0           $0           $0         $243          $52          $94           $0          $0          $0        $168
         Reduced tillage            $0         $218           $0         ^$61         $198         $229         $218          $0          $0        $174
 Cover Crops--non-legume            $0         $483           $0       $1,080         $415         $614         $483          $0          $0        $573
     Cover Crops--legume            $0         $273           $0         $295         $189         $278         $273          $0          $0        $256
      Cover Crops--mixed            $0         $412           $0         $641         $334         $462         $412          $0          $0        $434
                 Biochar           $25          $25          $25          $25          $25          $25          $25         $25          $0         $25
          Amend w/Manure           $88          $88          $88          $88          $88          $88          $88         $88          $0         $88
    Convert to Perennial           $34          $41           $0          $30          $28          $48          $24          $0          $0         $34
 Dairy Manure Management            $0           $0           $0           $0           $0           $0           $0          $0         $22         $22
         Riparian Buffer          $124         $124           $0         $106         $103         $132          $95          $0          $0        $122
--------------------------------------------------------------------------------------------------------------------------------------------------------

    All of these practices are presented as a single-focused 
implementation on a given parcel of land. In reality, some of these 
practices can be `bundled' and applied simultaneously. In addition, the 
dairy manure management practices do not overlap with the crop 
practices. Thus, Maine farmers could collectively amend their soil with 
biochar, reduce their tillage intensity, plant riparian buffers, and 
construct and utilize anaerobic digesters to manage dairy manure waste. 
If these options were simultaneously implemented across all eligible 
farms, then Maine could expect to mitigate up to 786,000 
tCO2e/yr in agricultural GHG emissions or about double the 
sector's current annual emissions. This combined approach is estimated 
to cost $26.3 million/yr or about $34/tCO2e. Future research 
will explore the technical and financial feasibility of creating 
different bundles of practices for agricultural NCS.
    The dairy manure management estimates summarized above were based 
on the assumptions that Maine's dairy farms collectively implemented a 
mix of the five different dairy NCS practices under consideration 
(Table 10). Breaking out dairy by specific NCS practices , which were 
primarily different sized and types of anaerobic digesters (AD), 
reveals that the larger options (i.e., complete mix AD and SLS) were 
the most cost effective, yielding break-even carbon prices of $6-$8/
tCO2e. However, these two practices would also need to rely 
on waste from several dairy farms. This is the case for the Summit 
Utilities Inc. anaerobic digester being constructed in Clinton, which 
is expected to collect waste from up to 17% of the state's dairy herd 
(Summit Utilities Inc., 2019). However, our results may be optimistic 
for Maine's dairy sector, which is often made up of small herds (2017 
Census of Agriculture, 2019). As a result, widespread implementation 
will likely require extensive cooperation, capital investment, and 
potentially long waste hauling distances to achieve the scale of 
mitigation that we have estimated.

                                  Table 10. Dairy manure management NCS summary
----------------------------------------------------------------------------------------------------------------
                                                Large
                                            Complete Mix     Covered                      Small
                                              Anaerobic      Lagoon/    Solid-liquid  Complete Mix  Plug Flow AD
                 Estimate                     Digester    Holding Pond   separation      AD with        with
                                              (AD) with      AD with        (SLS)      electricity   electricity
                                             electricity   electricity                 generation    generation
                                             generation    generation
----------------------------------------------------------------------------------------------------------------
Total constructed (no)                                12           100            30           100           100
Total GHG Mitigation (tCO2e/yr)                  148,800       209,700       244,860       148,800       128,700
Total Mitigation Cost ($/yr)                    $922,221    $9,329,591    $1,866,098    $5,290,110    $9,251,873
Break-even Carbon Price ($/tCO2e)                     $6           $44            $8           $36           $72
----------------------------------------------------------------------------------------------------------------

    The model estimates were dependent on a wide range of assumptions 
about how NCS practices affect yield, cost, and mitigation 
potential.\18\ As a result, we conducted a sensitivity analysis that 
tested the effect of our assessment when the `core' (medium) 
assumptions were modified to a `Low' and `High' input cost and yield 
impact case. The analysis indicates that the mitigation costs were most 
sensitive for reduced tillage, biochar, conversion to perennial set 
asides, and manure management (Figure 18, Figure 19). However, biochar 
and manure management were still estimated to be relatively cheap, even 
under the `high' cost case, and thus should not be ruled out even if 
actual costs are higher than our core assumptions. If we apply the same 
list of feasible practices discussed above across Maine's farms, then 
we estimate a Low total (break-even) cost of $17.4 mil/yr ($22/
tCO2e) and a High cost of $47.1 mil/yr ($60/
tCO2e). While this range is found to be higher than most of 
the forest NCS practices, it is still well within the range of other 
NCS and land-based mitigation studies (Fargione, et al., 2018; Griscom, 
et al., 2017; Roe, et al., 2019) as well as the cost of implementing 
non-NCS options like renewable energy (Riahi, et al., 2017).
---------------------------------------------------------------------------
    \18\ N.B., for this analysis we opted to exclude a low and high 
mitigation sensitivity due to the extreme range in emissions scenarios 
published in the literature. We hope to explore this impact in a future 
analysis.
---------------------------------------------------------------------------
Figure 18. Total Ag GHG Mitigation Cost by Sensitivity Case
(Mil $/yr)


          Total annual Maine agriculture NCS practice cost (mil $/yr) 
        by sensitivity case.
Figure 19. Total Ag GHG Mitigation Break-even Price by Sensitivity Case
($/tCO2e)


          Total annual Maine agriculture NCS practice break-even carbon 
        price ($/tCO2e) by sensitivity case.
4. Summary & Conclusions
    This study sought to estimate the financial costs and GHG 
mitigation benefits of implementing a range of NCS practices across 
Maine's farms and forests. A summary of the key findings are listed in 
Table 11. Based on this assessment, we found that the following five 
practices for each of the forestry and agriculture sectors provided the 
most mitigation potential in Maine at relatively low cost.

 
             Forestry:                          Agriculture:
 
  1.  50% clearcut area + planting    1.  Amend soil with biochar
  2.  35% clearcut + 20% set aside    2.  Convert to perennial grasses
  3.  35% clearcut + 10% set aside    3.  Dairy manure management
  4.  35% clearcut + planting         4.  Amend soil with manure
  5.  Afforest marginal crop and      5.  Plant riparian buffers
   pasture
 

    The results in Table 11 present the impacts if specific practices 
were implemented on their own. However, in some instances, a subset of 
NCS practices can be implemented simultaneously, either on the same 
farm/stand or in separate areas, which will be explored in more detail 
in a future analysis. On the forestry side, collectively changing 
forest management across 9.1 million acres in northern Maine to 50% 
clearcut followed by planting in addition to afforesting marginal land 
and reducing conversion of forests to cropland across the state could 
yield about 4.5 MtCO2e/yr in additional carbon sequestration 
at a cost of $64 million/yr or $14/tCO2e. In terms of 
agriculture, Maine farmers could collectively amend their soil with 
biochar, reduce their tillage intensity, plant riparian buffers, and 
construct and utilize anaerobic digesters to manage dairy manure waste, 
thereby mitigating up to 786,000 tCO2e/yr in GHG emissions 
or about double the sector's current annual emissions. This combined 
approach for the agricultural sector is estimated to cost $26.3 
million/yr or $34/tCO2e.
    With respect to forestry, our analysis found that annual harvests 
were reduced by 5% or less compared to the BAU, thereby ensuring a 
steady timber supply even with an increase in forest carbon. The key 
exception is the scenario with the constraint that stands must be at 
least 100 years old to harvest. As harvests in most scenarios were 
close to BAU, there was also minimal risk of `leakage' in the form of 
increased harvests and lost forest carbon outside of our study area. 
Our study also found that there are potential habitat tradeoffs with 
increased clearcuts and planting versus natural regeneration. Finally, 
we note that the average break-even carbon prices that we estimated for 
the sector are in the range of $10-$20/tCO2e. These prices 
are relatively inexpensive compared to typical carbon prices for other 
sectors of economy and social cost of carbon estimates, thus indicating 
that application of NCS practices in Maine's forest sector could be a 
cost-effective option to help meet the state's greenhouse gas reduction 
goals.

                      Table 11. Summary of key findings for Maine NCS mitigation potential
----------------------------------------------------------------------------------------------------------------
                                                                                                        Total
                                                               GHG       Mitigation    Break-even    Applicable
     Land-use  Sector               NCS Practice           Mitigation    Cost ($/yr)  Carbon Price   Area (acres
                                                           (tCO2e/yr)                   ($/tCO2e)     or cows)
----------------------------------------------------------------------------------------------------------------
Forestry                   BAU age (min 50)                          0          $0.0            $0     9,100,000
                           Min 85 years                        ^18,276         ^$1.9           $15     9,100,000
                           Min 100 years                       830,094         $16.2           $12     9,100,000
                           35% Clearcut (CC)                   ^69,900          $0.5            $6     9,100,000
                           50% Clearcut (CC)                   165,926          $5.9           $11     9,100,000
                           35% CC, plant                     2,453,073         $24.1           $11     9,100,000
                           50% CC, plant                     3,516,260         $37.1           $11     9,100,000
                           10% set-aside                       493,224          $9.0           $20     9,100,000
                           20% set-aside                     1,159,547         $21.3           $20     9,100,000
                           35% CC, plant, 10% set-aside      2,766,020         $31.4           $12     9,100,000
                           35% CC, plant, 20% set-aside      3,195,906         $41.3           $13     9,100,000
                           Afforestation                       759,617         $22.8           $30       360,000
                           Avoided Conversion--Crop            200,155          $4.1           $21        95,300
                           Avoided Conversion--Developed       685,428        $481.8          $703       327,800
Agriculture                No-till from Intensive               32,755          $3.0           $90        71,990
                           No-till from Reduced                 13,994          $2.4          $168        39,419
                           Reduced tillage                      13,423          $2.3          $174       134,229
                           Cover Crops                          24,161         $10.5          $434       134,229
                           Biochar                             568,898         $14.5           $25       355,561
                           Amend w/Manure                       55,112          $4.9           $88       355,561
                           Convert to Perennial                406,022         $12.4           $30       241,346
                           Riparian Buffer                      39,805          $4.6          $115        21,309
                           Large Complete Mix AD               150,997          $0.9            $6        30,443
                           Covered Lagoon/Holding Pond         212,797          $4.1           $19        30,443
                            AD
                           Solid-liquid separation (SLS)       129,565          $1.9           $15        30,443
                           Small Complete Mix AD               150,997          $5.4           $36        30,443
                           Plug Flow AD                         76,305          $9.4          $123        30,443
----------------------------------------------------------------------------------------------------------------

    For Maine agriculture our results point to a high mitigation 
potential from amending soil with biochar, converting cropland and 
pasture to perennial grasses, and constructing anaerobic digesters for 
dairy manure management. There is abundant literature from throughout 
the globe on the potential effect of biochar on reducing GHG emissions, 
but it is less proven at the commercial level, especially in conditions 
such as Maine. In addition, converting land to perennial grasses could 
potentially take cropland out of production, thereby reducing the 
amount of locally sourced food available to Mainers. Dairy management 
relies on the investment in digesters, which require financial capital. 
Despite these potential uncertainties, Maine's agricultural sector has 
the potential to reduce its within-sector emissions or even be net-
negative as a sector while enhancing the sustainability and health of 
Maine's farms and food systems.
    We note that there are some important model limitations that could 
be addressed in future research applied to our forestry NCS assessment. 
First, the Landis-based model estimates were based on only a single 
`run' for each scenario that quasi-randomly selected which stands to 
harvest and/or plant. Conducting multiple model runs for the same 
management scenario would provide additional insight on the level of 
uncertainty surrounding the carbon estimates. The second limitation is 
that the analysis only covered the northern half of the state. To 
provide a statewide context for our estimates, we incorporated carbon 
information derived from FIA data for areas outside our project study 
area (Appendix C). Encompassing the carbon dynamics of southern Maine 
to a degree equal to the efforts demonstrated here for northern Maine 
should be a priority for future research.
    Our results show limited carbon sequestration of the agricultural 
NCS practices in Maine compared to forestry. Our model also only 
assessed their impact on yield and net GHG emissions and no other 
cobenefits such as the provision of other ecosystem services, improved 
climate change adaptation, and enhanced farm resilience. Further, 
locally collected data were often unavailable to inform our modeling 
approach, so many parameter values were drawn from regional estimates 
or extrapolated from growing systems with similarities to Maine as 
detailed in our methods description. Additional biophysical research 
specific to NCS practice application in Maine crops and cropping 
systems is needed to better understand local yield impacts and soil 
carbon sequestration dynamics. Further research could incorporate 
quantification of the potential co-benefits of NCS on aspects such as 
water quality and quantity and soil health. The analysis could also be 
extended to investigate interactions between the forestry and 
agricultural sectors.
    Our analysis also assumed that the practices would be fully 
implemented across all eligible land. In reality, not every farmer and 
forest landowner will have the technical and financial resources, or 
the inclination in light of their own circumstances, to undertake some 
of these practices. For example, while we found biochar to be an 
extremely cost-effective opportunity for Maine's agricultural sector, 
particularly given the abundance of raw materials available to produce 
biochar, very few farmers are currently implementing this on their land 
in Maine. As a result, we are using interviews and focus groups to 
explore the potential technical, financial, social, and/or policy 
barriers and opportunities that stakeholders face in implementing the 
NCS practices presented in this report that may limit the ability to 
reach our estimated potential. These findings will be incorporated into 
future modeling efforts.
    Finally, we offer two closing thoughts in light of this initial 
study. First, it is clear that while there is a tremendous body of 
knowledge in the literature upon which to draw to undertake these 
technical analyses, it is essential to support Maine decision-makers 
with Maine-based data and experience given the unique historical, 
biophysical, and socioeconomic character of Maine. Maine's spruce-
forests are not like southern pine and Maine's potato production 
systems and markets are not like California. Second, most of these NCSs 
have important contributions to make to the urgent need to reduce 
greenhouse gas concentrations in the atmosphere, and at the same time 
they typically provide vital co-benefits that are often lumped into a 
term like ecosystem services. It should be noted, however, that most 
but not all are finite. We can increase carbon in forests and soils up 
to a point, but not forever. That makes their contributions between now 
and mid-century most critical for investment.
Appendix A. Detailed Results

             Table 12. Maine forest NCS estimates for core (medium) analysis, 20 and 50 year means.
----------------------------------------------------------------------------------------------------------------
                                  Total Carbon Above  Harvest Volume (gt/ Mitigation Cost ($/ Break-even  Carbon
            Scenario             Baseline (tCO2e/yr)          yr)                 yr)          Price  ($/tCO2e)
----------------------------------------------------------------------------------------------------------------
                                            20 Year Mean (2020-2040)
----------------------------------------------------------------------------------------------------------------
           BAU age (min 50)                     0           9,218,608                  $0                  $0
               Min 85 years               977,442           8,293,587         $12,288,424                 $14
              Min 100 years             3,731,440           5,034,894         $55,578,455                 $15
          35% Clearcut (CC)               322,382           8,758,310          $6,114,819                  $2
          50% Clearcut (CC)               904,263           8,042,478         $15,624,267                 $19
              35% CC, plant             2,094,584           8,752,861         $29,847,046                 $15
              50% CC, plant             3,255,452           8,046,626         $47,118,239                 $15
              10% set-aside               592,715           8,532,867          $9,109,711                 $15
              20% set-aside             1,370,633           7,631,017         $21,090,314                 $15
35% CC, plant, 10% set-aside            2,536,070           8,103,470         $36,888,130                 $15
35% CC, plant, 20% set-aside            3,121,529           7,240,923         $31,400,585                 $15
              Afforestation               735,443           9,218,608         $22,063,299                 $30
   Avoided Conversion--Crop               100,086           9,218,608          $2,058,912                 $21
Avoided Conversion--Developed             341,358           9,218,608        $239,925,645                $703
----------------------------------------------------------------------------------------------------------------
                                             50 yr mean (2020-2070)
----------------------------------------------------------------------------------------------------------------
           BAU age (min 50)                     0           9,332,668                  $0                  $0
               Min 85 years               ^18,276           9,475,356         ^$1,895,530                 $15
              Min 100 years               830,094           8,115,025         $16,175,762                 $12
          35% Clearcut (CC)               ^69,900           9,291,435            $547,764                  $6
          50% Clearcut (CC)               165,926           8,887,980          $5,907,455                 $11
              35% CC, plant             2,453,073           9,301,018         $24,080,330                 $11
              50% CC, plant             3,516,260           8,911,726         $37,139,123                 $11
              10% set-aside               493,224           8,654,385          $9,010,648                 $20
              20% set-aside             1,159,547           7,728,575         $21,309,545                 $20
35% CC, plant, 10% set-aside            2,766,020           8,630,582         $31,400,585                 $12
35% CC, plant, 20% set-aside            3,195,906           7,708,553         $41,327,285                 $13
              Afforestation               759,617           9,332,668         $22,788,513                 $30
   Avoided Conversion--Crop               200,155           9,332,668          $4,117,478                 $21
Avoided Conversion--Developed             685,428           9,332,668        $481,757,790                $703
----------------------------------------------------------------------------------------------------------------


                         Table 13. Maine agricultural NCS estimates by sensitivity case.
----------------------------------------------------------------------------------------------------------------
                          Total             Total Cost (Mil $/yr)                Break-Even Price ($/tCO2e)
                        Mitigation -----------------------------------------------------------------------------
     NCS Practice       (tCO2e/yr)
                      -------------     Low         Medium        High         Low         Medium        High
                          Medium
----------------------------------------------------------------------------------------------------------------
        No-till from        32,755        $1.70        $2.96        $4.22          $52          $90         $129
            Intensive
No-till from Reduced        13,994        $2.21        $2.36        $2.50         $158         $168         $178
     Reduced tillage        13,423       ^$1.91        $2.34        $7.15        ^$142         $174         $532
         Cover Crops        24,161        $6.80       $10.48       $13.28         $281         $434         $549
             Biochar       568,898       $10.86       $14.48       $28.96          $19          $25          $51
      Amend w/Manure        55,112        $0.81        $4.85        $6.44          $15          $88         $117
Convert to Perennial       406,022        $7.97       $12.38       $21.24          $20          $30          $52
     Riparian Buffer        39,805        $3.41        $4.57        $5.73          $86         $115         $144
  Dairy Manure Mgmt.       144,132        $1.42        $4.33        $8.14          $10          $30          $56
----------------------------------------------------------------------------------------------------------------

Appendix B. Detailed Input Data
Maine forest systems

            Table 14. Landis baseline area by species, 2010.*
------------------------------------------------------------------------
               Species                           Area (acres)
------------------------------------------------------------------------
              Red Maple                             2,933,457
             Balsam Fir                             2,915,428
           Yellow Birch                             2,287,363
             Red Spruce                             2,244,374
            Sugar Maple                             1,933,383
   Northern White Cedar                             1,386,127
            Paper Birch                             1,264,980
         American Beech                               967,934
        Eastern Hemlock                               479,583
           Black Spruce                               462,059
              White Ash                               449,635
   Eastern Whi[t]e Pine                               449,049
           White Spruce                               326,810
------------------------------------------------------------------------
* Acres sum to more than the 10 million acres in total area covered by
  Landis because any given 30mpixel in the model can have anywhere from
  1 to 13 species present.

Maine cropping systems
    The following section includes additional information on each of 
the agricultural enterprise systems and detailed budgetary information. 
For all of the enterprises, costs were adjusted to 2017 dollars based 
on the Producer Price Index (PPI) to account for inflation, and revenue 
is based on a 5-yr (2012-2017) average of the commodity price in Maine 
(Crop Values Annual Summary, 2020).
Apples
    The financial budget for an apple system is calculated based on 
bearing fruit acres and was created based on economic information from 
a Cornell University study (Schmit, et al., 2018).

                     Table 15. Apple orchard budget
------------------------------------------------------------------------
               Component                      Per bearing fruit acre
------------------------------------------------------------------------
                                 Revenue
------------------------------------------------------------------------
                 Yield (lbs)                           30243.5
                       Price                             $0.31
           Estimated Revenue                         $8,196.00
------------------------------------------------------------------------
                             Variable Costs
------------------------------------------------------------------------
                            Labor                    $2,855.00
             Chemical Inputs                         $1,052.00
Insurance, Utilities, Interest, and                    $541.00
 professional/technical services
Equipment expenses (fuel, oil,                         $481.00
 trucking, maintenance, leasing)
  Miscellaneous Expenditures                              $630
                                        --------------------------------
  Total Variable Costs.................              $5,559.00
------------------------------------------------------------------------
                               Fixed Costs
------------------------------------------------------------------------
Real estate costs (repair, taxes, and                  $407.00
                     leasing)
                                        --------------------------------
                 Total Costs                         $5,966.00
                 Net Revenue                         $2,230.00
   Return over Variable Cost                         $2,637.00
------------------------------------------------------------------------

Barley
    According to the 2017 USDA NASS Census of Agriculture, 15,115 acres 
of barley were grown for grain (2017 Census of Agriculture, 2019). The 
financial budget for a typical barley cropping system assumes a farm of 
26 planted acres. Costs were adapted from data from the USDA Economic 
Research Service for the Northeast region and is partly based on USDA's 
Agricultural Resource Management Survey (Commodity Costs and Returns, 
2020).
    Table 16 summarizes the key revenues and costs for a typical Maine 
barley cropping system.

                      Table 16. Barley farm budget.
------------------------------------------------------------------------
                                      Total           Per planted acre
------------------------------------------------------------------------
                                 Revenue
------------------------------------------------------------------------
       Number of acres                      26
                 Yield                    (bu)               1248 48
                 Price                  ($/bu)                 $3.87
 Primary product grain               $4,825.60               $185.60
Secondary product silage/              $871.55                $33.52
          straw/grazing
                             -------------------------------------------
  Annual Revenue............         $5,697.15               $233.25
------------------------------------------------------------------------
                             Variable costs
------------------------------------------------------------------------
                  Seed                 $741.59                $28.52
          Fertilizer a               $1,313.84                $50.53
             Chemicals                  $57.95                 $2.23
       Custom services                 $699.20                $26.89
Fuel, lube, and electricity            $426.49                $16.40
               Repairs                 $504.51                $19.40
Other variable expenses b               $33.87                 $1.30
Interest on operating inputs            $39.39                 $1.51
                             -------------------------------------------
  Total Variable Costs......         $3,816.85               $146.80
------------------------------------------------------------------------
                               Fixed costs
------------------------------------------------------------------------
           Hired labor                  $54.44                 $2.09
Opportunity cost of unpaid           $1,398.64                $53.79
                  labor
   Capital recovery of               $1,651.27                $63.51
 machinery and equipment
Opportunity cost of land             $2,281.23                $87.74
   Taxes and insurance                 $146.26                 $5.63
 General farm overhead                 $337.43                $12.98
                             -------------------------------------------
  Total Fixed Costs.........         $5,869.28               $225.74
------------------------------------------------------------------------
           Total Costs               $9,686.12               $372.54
           Net Revenue              ^$3,988.98              ^$139.29
                             ===========================================
  Net Revenue over Variable          $1,880.30                $86.45
   Costs....................
------------------------------------------------------------------------
a Cost of commercial fertilizers, soil conditioners, and manure.
b Cost of purchased irrigation water and straw baling.

Blueberries
    Lowbush blueberries are clonal perennial shrubs that tolerate 
marginal, poorly drained sites but most commercial production takes 
place on freely drained and often sandy soils, most commonly under 
acidic soil conditions. They are managed on a 2 year cycle that 
utilizes mowing or (less commonly these days) burning in the non-
production year to maximize floral initiation, fruit set, yield, and 
ease of mechanical harvest during the production year. About 70% of 
blueberry plants' biomass is found underground in rhizomes, which 
enables their recovery from biannual mowing or burning (Files, et al., 
2008). An average of 14 gallons of diesel fuel per acre are required 
for mowing, whereas 80 gallons of diesel fuel per acre is required for 
burning. Other important field operations and inputs include rental of 
honeybees for pollination during production years, use of N-P-K 
fertilizers, applications of sulfur (often applied at a concentration 
of 1,000 lbs/acre) (Files, et al., 2008) to lower pH and manage weeds, 
application of herbicides, fungicides, and insecticides, and irrigation 
on an as-needed basis during both production and non-production years 
(Yarborough, 2012).
    According to former Extension wild blueberry specialist Dave 
Yarborough, opportunities for enhanced carbon sequestration in this 
crop may be limited because ``wild blueberries do not store much 
biomass as plants are pruned every other year and there is a slow 
decomposition of the cut stems. Prior to the 1970's, plant[s] were 
burned with #2 fuel oil and so we had a much higher carbon emission in 
the past but now most are mowed; so most of the carbon benefits have 
been accrued in past years with this change in practice.'' \19\ 
However, use of organic mulches including living mulches, as well as 
use of cover crops in lowbush blueberry systems, represent areas of 
theoretical promise in which new research is currently being 
conducted.\20\
---------------------------------------------------------------------------
    \19\ D. Yarborough, personal communication, January 27, 2020.
    \20\ L. Calderwood, personal communication, January 9, 2020.
---------------------------------------------------------------------------
    The financial budget for a typical blueberry cropping system was 
adapted from an enterprise budget prepared by the University of Maine 
Cooperative Extension (Blueberry Enterprise Budget, 2016) and reflects 
the following assumptions: a medium yield, conventional farm of 58 
acres. Table 17 summarizes the key revenues and costs for a typical 
Maine blueberry cropping system.

           Table 17. Lowbush Blueberry Farm Financial Budget.
------------------------------------------------------------------------
                                  Total         ($/Acre)       ($/lb)
------------------------------------------------------------------------
                                 Revenue
------------------------------------------------------------------------
    Number of Acres (Crop)           58.06
               Yield (lbs)         258,089
         Yield (lbs./Acre)        4,445.21
              Price ($/lb)            0.47
                             -------------------------------------------
  Annual Revenue............    122,024.43       2,101.70           0.47
------------------------------------------------------------------------
                             Variable Costs
------------------------------------------------------------------------
Pruning (burning and mowing)        $7,234           $125          $0.03
              Weed Control          $7,471           $129          $0.03
             Fertilization          $7,710           $133          $0.03
               Pollination         $15,435           $266          $0.06
           Pest Monitoring            $531             $9          $0.00
            Insect Control          $2,198            $38          $0.01
           Disease Control          $4,099            $71          $0.02
                Irrigation              $0             $0          $0.00
               Sulfur (pH)              $0             $0          $0.00
       Harvest (raking and         $36,711           $632          $0.14
                mechanical)
     Packing and Marketing              $0             $0          $0.00
       Interest on Capital          $2,571            $44          $0.01
             Blueberry Tax          $3,354            $58          $0.01
                             -------------------------------------------
  Total Variable Costs......       $87,315         $1,504          $0.34
  Total Costs...............       $87,315         $1,504          $0.34
                             ===========================================
    Net Revenue.............       $34,709           $598          $0.13
------------------------------------------------------------------------

Corn
    According to the 2017 USDA NASS Census of Agriculture, 7,237 acres 
of corn were grown for grain and 25,344 acres were grown for corn 
silage (2017 Census of Agriculture, 2019). Silage corn is planted at 
soil temperatures above 50 F, typically takes 70-95 days to grow to 
maturity, and yields 18-30 tons per acre of 30% dry matter feed.\21\ 
No-till (NT) and reduced-tillage (RT) practices are applicable to this 
crop, and biochar and set-aside programs may be as well. After harvest, 
silage corn is typically stored for fermentation in bunkers or silos. 
The financial budget is adapted from an enterprise budget prepared by 
the University of Maine Agricultural and Forestry Experimental Station 
(Hoshide, et al., 2004) and assumes a 160 acre farm. Table 18 
summarizes the key revenues and costs for a typical Maine silage corn 
cropping system.
---------------------------------------------------------------------------
    \21\ R. Kersbergen, personal communication, Spring 2018.

              Table 18. Silage Corn Farm Financial Budget.
------------------------------------------------------------------------
                                  Total         Per Acre       Per Bu
------------------------------------------------------------------------
                                 Revenue
------------------------------------------------------------------------
           Number of Acres             160
     Grain Corn Yield (bu)          16,000            100
              Price ($/bu)           $3.69
                             -------------------------------------------
  Annual Revenue............       $59,008        $368.80          $3.69
------------------------------------------------------------------------
                             Variable Costs
------------------------------------------------------------------------
                      Seed          $5,918         $36.99          $0.37
                Fertilizer         $14,434         $90.21          $0.90
                          Lime  $2,677.433         $16.73          $0.17
                 Chemicals          $5,382         $33.64          $0.34
                          Labor     $8,121         $50.75          $0.51
       Diesel Fuel and Oil          $2,853         $17.83          $0.18
    Maintenance and Upkeep          $5,221         $32.63          $0.33
                  Supplies          $2,207         $13.79          $0.14
                 Insurance             $73          $0.46          $0.00
                 Utilities            $441          $2.76          $0.03
                  Rent or Lease     $2,759         $17.24          $0.17
                    Drying          $4,264         $26.65          $0.27
                  Interest          $1,501          $9.38          $0.09
                             -------------------------------------------
  Total Operating Expenses..       $55,851        $349.07          $3.49
------------------------------------------------------------------------
                               Fixed Costs
------------------------------------------------------------------------
 Depreciation and Interest         $33,493        $209.33          $2.09
         Tax and Insurance          $2,444         $15.28          $0.15
                             -------------------------------------------
  Total Ownership Expenses..       $35,938        $224.61          $2.25
                             -------------------------------------------
         Total Annual Cost         $91,789        $573.68          $5.74
     Net Farm Income (NFI)        ^$32,781       ^$204.88         ^$2.05
                             ===========================================
  Return over Variable Cost         $3,157         $19.73          $0.20
   (ROVC)...................
------------------------------------------------------------------------

Dairy
    The dairy production cycle begins with the birth of a calf, which 
induces milk production. Milk is harvested for a 10-12 month period, 
which overlaps with the first seven months of the next nine month 
gestation period. The last two months prior to calving are usually a 
dry period provided for the health of the cow.
    Overall a mature dairy cow produces a calf every 12 to 14 months. 
Mature cows are replaced or culled from the herd at a rate of about 25% 
of a milking herd per year. Approximately 50% of new female calves are 
kept (sometimes sent elsewhere to be raised) for replacement, and reach 
the age of first calving at about 24 months, while the remaining excess 
calves are sold for veal or beef production (CAFO Permit Guidance 
Appendix B: Animal Sector Descriptions, 2003). Management-intensive 
rotational grazing (MIRG) is often considered an environmental best-
practice (Undersander, et al., 1993). The financial budget for a 
typical dairy system is adapted from an enterprise budget prepared by 
the University of Maine Agricultural and Forestry Experimental Station 
(Hoshide, et al., 2004) and assumes a coupled dairy and hayfield farm 
with 66 cows. The values in the budget are per cow, rather than per 
acre. Table 19 summarizes the key revenues and costs for a typical 
Maine dairy cropping system.

                      Table 19. Dairy Farm Budget.
------------------------------------------------------------------------
                                  Total         Per Cow        Per Cwt
------------------------------------------------------------------------
                                 Revenue
------------------------------------------------------------------------
            Number of Cows              66             --             --
Annual Milk Shipment (cwt)          10,413         157.77             --
  Milk Receipts.............  $1,643,983,61        $18.08          $0.93
                                         4
  Crop and Hay Revenue......   $42,266,367          $0.46          $0.02
  Livestock Revenue.........   $90,905,490          $1.00          $0.05
                             -------------------------------------------
    Total Revenue...........  $1,777,155,47        $19.55          $1.00
                                      1.00
------------------------------------------------------------------------
                             Variable Costs
                             Labor Expenses
------------------------------------------------------------------------
                    Family              $0          $0.00          $0.00
                     Hired    $112,710,312          $1.24          $0.06
                             -------------------------------------------
  Subtotal..................  $112,710,312.         $1.24          $0.06
                                        00
------------------------------------------------------------------------
                         Purchased Feed Expenses
------------------------------------------------------------------------
              Dairy Forage              $0          $0.00          $0.00
         Dairy Concentrate    $440,928,072          $4.85          $0.25
                             -------------------------------------------
  Subtotal..................  $440,928,072.         $4.85          $0.25
                                        00
------------------------------------------------------------------------
                           Livestock Expenses
------------------------------------------------------------------------
             Breeding Fees     $20,524,023          $0.23          $0.01
   Veterinary and Medicine     $43,745,013          $0.48          $0.02
                   Bedding     $24,595,506          $0.27          $0.01
             DHIA Expenses      $7,591,077          $0.08          $0.00
                          Lives$15,473,718nce       $0.17          $0.01
                             -------------------------------------------
  Subtotal..................  $111,929,337.         $1.23          $0.06
                                        00
------------------------------------------------------------------------
                        Crop and Pasture Expenses
------------------------------------------------------------------------
                     Seeds     $33,675,642          $0.37          $0.02
                 Chemicals     $24,887,070          $0.27          $0.01
                Fertilizer     $23,408,424          $0.26          $0.01
                          Lime $19,982,547          $0.22          $0.01
                     Other     $52,356,564          $0.58          $0.03
                             -------------------------------------------
  Subtotal..................  $154,310,247.         $1.70          $0.09
                                        00
------------------------------------------------------------------------
                   Maintenance and Equipment Expenses
------------------------------------------------------------------------
              Fuel and Oil     $61,457,526          $0.68          $0.03
         Machinery Repairs    $124,810,218          $1.37          $0.07
                             -------------------------------------------
  Subtotal..................  $186,267,744.         $2.05          $0.10
                                        00
------------------------------------------------------------------------
                           Deduction Expenses
------------------------------------------------------------------------
            Milk Marketing     $15,057,198          $0.17          $0.01
      Hauling and Trucking     $66,684,852          $0.73          $0.04
                             -------------------------------------------
                  Subtotal    $81,742,050.0         $0.90          $0.05
                                         0
Interest (5.4% on \1/2\ of    $29,372,969.5         $0.32          $0.02
   total operating expense)              7
                             ===========================================
  Total Variable Costs......  $1,117,260,73        $12.29          $0.63
                                      1.57
------------------------------------------------------------------------
                               Fixed Costs
                        Annual Overhead Expenses
------------------------------------------------------------------------
              Property Tax     $81,939,897          $0.90          $0.05
            Farm Insurance     $82,085,679          $0.90          $0.05
Dues and Professional Fees     $10,600,434          $0.12          $0.01
                 Utilities     $66,247,506          $0.73          $0.04
             Miscellaneous    $155,632,698          $1.71          $0.09
                             -------------------------------------------
  Subtotal..................  $396,506,214.         $4.36          $0.22
                                        00
------------------------------------------------------------------------
                Annual Depreciation and Interest Expenses
------------------------------------------------------------------------
                          Land $84,147,453          $0.93          $0.05
                 Buildings    $268,009,794          $2.95          $0.15
   Machinery and Equipment    $174,417,750          $1.92          $0.10
                             -------------------------------------------
  Subtotal..................  $526,574,997.         $5.79          $0.30
                                        00
------------------------------------------------------------------------
                         Livestock Herd Expenses
------------------------------------------------------------------------
    Cows (Milking and Dry)    $108,753,372          $1.20          $0.06
  Heifers...................   $45,890,091          $0.50          $0.03
  Calves....................   $17,264,754          $0.19          $0.01
  Dairy Bulls...............      $780,975          $0.01          $0.00
                             -------------------------------------------
    Subtotal................  $172,689,192.         $1.90          $0.10
                                        00
                             -------------------------------------------
      Total Fixed Costs.....  $1,095,770,40        $12.05          $0.62
                                      3.00
      Total Annual Cost.....  $2,213,031,13        $24.34          $1.25
                                      4.57
                             ===========================================
      Net Farm Income (NFI).  ^$435,875,663        ^$4.79         ^$0.25
                                       .57
      Return over Variable    $659,894,739.         $7.26          $0.37
       Cost (ROVC)..........            43
------------------------------------------------------------------------

Hay
    Hay is the most harvested crop in Maine by acreage. Grasslands are 
not a native ecosystem type in Maine, and without human intervention in 
the form of periodic mowing, early successional woody species including 
alders, birches, and poplars will invade, beginning the process through 
which, left to its own devices, the land will transition back to 
forest. It is possible that reversion of some hayfields to forest could 
be beneficial from an NCS standpoint. The financial budget for a 
typical hayfield cropping system is adapted from an enterprise budget 
prepared by the University of Maine Agricultural and Forestry 
Experimental Station (Hoshide, et al., 2004) and assumes that 200 acres 
of hay is grown. Table 20 summarizes the key revenues and costs for a 
typical Maine hayfield cropping system.

        Table 20. Conventional and Coupled Medium-Large Haylage.
------------------------------------------------------------------------
                                  Total         Per Acre       Per Ton
------------------------------------------------------------------------
                                 Revenue
------------------------------------------------------------------------
           Number of Acres             200
      Haylage Yield (tons)           1,200              6
             Price ($/ton)         $165.40
                             -------------------------------------------
  Total Revenue.............   $19,8480.00        $992.40        $165.40
------------------------------------------------------------------------
                             Variable Costs
------------------------------------------------------------------------
                     Seeds           $0.00             $0             $0
                Fertilizer       $8,607.51         $43.04          $7.17
                          Lime   $2,758.82         $13.79          $2.30
                 Chemicals           $0.00          $0.00          $0.00
                          Labor $10,023.28         $50.12          $8.35
       Diesel Fuel and Oil       $4,014.08         $20.07          $3.35
    Maintenance and Upkeep       $4,062.36         $20.31          $3.39
                  Supplies       $2,758.82         $13.79          $2.30
                 Insurance          $91.04          $0.46          $0.08
    Miscellaneous Rent or Lease  $3,448.52         $17.24          $2.87
  Storage and Warehousing...       $275.88          $1.38          $0.23
  Other Expenses............     $1,379.41          $6.90          $1.15
                  Interest         $736.60          $3.68          $0.61
                             -------------------------------------------
    Total Variable Costs....       $38,156        $190.78         $31.80
------------------------------------------------------------------------
                               Fixed Costs
------------------------------------------------------------------------
 Depreciation and Interest         $24,410        $122.05         $20.34
         Tax and Insurance          $1,944          $9.72          $1.62
                             -------------------------------------------
  Total Fixed Costs.........       $26,354        $131.77         $21.96
  Total Annual Cost.........       $64,510        $322.55         $53.76
                             ===========================================
    Net Farm Income (NFI)...      $133,970        $669.85        $111.64
    Return over Variable          $160,324        $801.62        $133.60
     Cost (ROVC)............
------------------------------------------------------------------------
Numbers may not sum due to rounding.

Potato
    Potatoes are second to hay in acres harvested in Maine. Growers 
selling to the processing market are generally under contract with the 
buyer who can have considerable influence on what growing practices are 
employed. Growers for the processing market generally receive bonuses 
for potato size and quality, ability to store the crop until 
processing, and for highest yield.\22\ Most growers are using a 1:1 
rotation with one year of potatoes and one year of a much less valuable 
cash crop like a grain or an unharvested cover crop. Some growers are 
using a 2:1 rotation with a longer ``off'' period from potatoes.\23\ 
Potato cropping involves key vulnerable periods with respect to 
potential soil erosion and loss of soil organic matter. Potatoes take 
about three weeks to emerge after planting, leaving the soil 
susceptible to erosion during this time.\24\ Soils are also generally 
uncovered and susceptible after potato harvest, as well as following 
fall tillage in the preceding rotation crop.\25\ The multiple tillage/
cultivation passes inherent to potato planting and hilling are harmful 
for soil organic matter and aggregation (i.e., good soil structure), 
and despite the adoption of one-pass hilling by some growers, potato 
cropping systems remain by necessity tillage-intensive. Nurse cropping 
(Jemison, 2019), use of organic amendments (Mallory & Porter, 2007), 
and transition to longer rotations represent key opportunities to 
improve soil health in Maine potato cropping systems. The financial 
budget for a typical potato cropping system assumes the farm is 320 
acres that grows 160 acres each of potatoes and corn in rotation. Table 
21 summarizes the key revenues and costs for a typical Maine potato 
cropping system.
---------------------------------------------------------------------------
    \22\ J. Jemison personal communication, February 2018.
    \23\ N. Lounsbury, unpublished data, January 23, 2020.
    \24\ J. Jemison personal communication, February 2018.
    \25\ Lounsbury, unpublished data, January 23, 2020.

                      Table 21. Potato Farm Budget.
------------------------------------------------------------------------
 
------------------------------------------------------------------------
                                 Revenue
------------------------------------------------------------------------
                              Potato (cwt)      Corn (bu)
------------------------------------------------------------------------
           Number of acres             160            160
                Yield/acre             240            100
                     Yield          38,400          8,960
                Unit Price          $10.46          $3.69
                             ------------------------------
  Annual Revenue............      $401,664     $33,044.48
                             -------------------------------------------
  Total Revenue.............   $19,8480.00        $992.40        $165.40
------------------------------------------------------------------------
                                     Total       Per Acre        Per Cwt
------------------------------------------------------------------------
                             Variable Costs
------------------------------------------------------------------------
                      Seed         $57,463        $179.57          $1.21
                Fertilizer         $45,534        $142.29          $0.96
                          Lime      $4,884         $15.26          $0.10
                 Chemicals         $41,711        $130.35          $0.88
                          Labor    $58,728        $183.53          $1.24
       Diesel Fuel and Oil         $19,486         $60.89          $0.41
    Maintenance and Upkeep         $29,710         $92.84          $0.63
                  Supplies         $14,918         $46.62          $0.31
                 Insurance         $12,300         $38.44          $0.26
------------------------------------------------------------------------
                              Miscellaneous
------------------------------------------------------------------------
                 Utilities          $8,857         $27.68          $0.19
               Custom Hire              $0          $0.00          $0.00
                  Rent or Lease    $16,553         $51.73          $0.35
      Freight and Trucking          $3,930         $12.28          $0.08
   Storage and Warehousing          $6,857         $21.43          $0.14
            Other Expenses          $1,324          $4.14          $0.03
                  Interest          $8,900         $27.81          $0.19
                             -------------------------------------------
  Total Variable Costs......   $331,156.06      $1,034.86          $6.99
------------------------------------------------------------------------
                               Fixed Costs
------------------------------------------------------------------------
 Depreciation and Interest        $104,264        $325.82          $1.60
         Tax and Insurance          $6,767         $21.15          $0.10
                             -------------------------------------------
  Total Fixed Costs.........   $111,031.38        $346.97          $1.70
  Total Annual Cost.........   $442,187.44      $1,381.84          $8.69
                             ===========================================
    Net Farm Income (NFI)...    $18,484.56         $57.76          $1.03
    Return over Variable       $129,515.94        $404.74          $2.73
     Cost...................
------------------------------------------------------------------------
Numbers may not sum due to rounding.

Diversified vegetable
    The financial budget for a typical diversified vegetable cropping 
system assumes a 150 acre farm with 120 acres in woodlot, 10 acres in 
annual vegetable production, 10 acres in cover crops, and 10 acres in 
animal pasture. We assume that the farm grows beans, bell peppers, 
cucumbers, peas, pumpkins, sweet corn, squash, and tomatoes. This 
assumption is based on expert consultation and data from the 2017 USDA 
Census of Agriculture (2017 Census of Agriculture, 2019). The crops are 
grown in five hundred 100 rows. Table 22 summarizes the key revenues 
and costs for a typical Maine diversified vegetable cropping system.
    Use of biochar is thought to be minimal in Maine at present,\26\ 
but because diverse rotations that often include numerous field 
operations per season are common, there exist many opportunities to 
incorporate organic amendments including biochar into diversified 
vegetable systems. Use of mulches is common in these systems, and 
particularly in the case of organic mulch, represents an additional 
means of improving soil health (Conservation Practice Standard: 
Mulching, 2017). Conservation set-aside programs, where a portion of 
the land is put into conservation uses, are also feasible in these 
systems.
---------------------------------------------------------------------------
    \26\ S. O'Brian, unpublished data, Fall 2019.

              Table 22. Diversified vegetable farm budget.
------------------------------------------------------------------------
                                               Total Veg
       Cost Component         Mean Veg (100   part of farm  Total/veg ac
                                   row)        (500 rows)
------------------------------------------------------------------------
                   Revenue         $442.35       $221,174    $ 22,117.43
            Variable Costs         $234.48       $117,238     $11,723.78
               Fixed Costs         $111.05        $55,524      $5,552.38
                             -------------------------------------------
  Mixed Veg Total Costs.....       $345.52       $172,762     $17,276.16
                             ===========================================
    Return over variable           $207.87       $103,936     $10,393.64
     costs..................
    Return over total costs.        $96.83        $48,413      $4,841.26
------------------------------------------------------------------------

Wheat
    According to the 2017 USDA NASS Census of Agriculture, 262 acres of 
winter wheat were grown in Maine (2017 Census of Agriculture, 2019). 
The financial budget for a typical wheat cropping system was adapted 
from an enterprise budget created by the University of Maine 
Cooperative Extension (Kary, et al., 2011). We assume the farm is 90 
acres and produces 45 acres each of wheat and straw.
    Table 23 summarizes the key revenues and costs for a typical Maine 
wheat cropping system.

                                             Table 23. Wheat budget.
----------------------------------------------------------------------------------------------------------------
                                          Unit              Unit/Acre         Revenue/Unit        Revenue/Acre
----------------------------------------------------------------------------------------------------------------
                                                     Revenue
----------------------------------------------------------------------------------------------------------------
                        Wheat                  bu.                  45              $15.42            $693.88
                        Straw             sq. bale                  45               $3.34            $150.34
                                                                                              ------------------
  Annual Revenue.................                                                                     $844.21
----------------------------------------------------------------------------------------------------------------
                                                 Variable Costs
                                                Material Expenses
----------------------------------------------------------------------------------------------------------------
                   Wheat Seed                   lb                 120               $0.51             $61.68
                       Manure                  ton                   5              $12.85             $64.25
              Chilean Nitrate                  ton                0.05             $868.63             $43.43
                             Lime              ton                 0.2              $20.56              $4.11
                                                                                              ------------------
  Subtotal.......................                                                                     $168.75
----------------------------------------------------------------------------------------------------------------
                                             Miscellaneous Expenses
----------------------------------------------------------------------------------------------------------------
                 Grain Drying                  bu.                  45               $0.34             $15.27
                             Leased Land      acre                0.25              $51.40             $12.85
                        Extra                    %               5.00%                 N/A             $14.99
                     Interest                    %               4.73%                 N/A              $8.60
                                                                                              ------------------
  Subtotal.......................                                                                      $51.71
----------------------------------------------------------------------------------------------------------------
                                            Field Operation Expenses
----------------------------------------------------------------------------------------------------------------
              Primary Tillage                 pass                   1               $6.61              $6.61
            Secondary Tillage                 pass                   2               $4.81              $9.62
             Manure Spreading                 pass                   1              $23.91             $23.91
         Fertilizer Spreading                 pass                   1               $3.14              $3.14
                             Lime Spreading   pass                 0.2               $3.14              $0.63
               Planting Wheat                 pass                   1               $5.54              $5.54
                    Combining                 pass                   1              $31.97             $31.97
                Hauling Wheat                 pass                   1               $2.08              $2.08
                 Baling Straw                 pass                   1               $6.18              $6.18
                Hauling Straw                 pass                   1               $2.05              $2.05
                                                                                              ------------------
  Subtotal.......................                                                                      $91.71
    Total Variable Costs.........                                                                     $312.17
                                                                                              ==================
      Total Costs................                                                                     $312.17
      Net Revenue................                                                                     $532.04
----------------------------------------------------------------------------------------------------------------

Natural Climate Solutions for Agriculture
    Emissions factor estimates for agricultural NCS practices used in 
our model, accompanied by relevant citations and notes, are outlined in 
Table 24 and 25. Additional input assumptions that we applied for the 
dairy manure management practices are listed in Table 26. Information 
and literature reviews concerning NCS practices and their applicability 
to growing systems in Maine is contained in the following sections of 
text corresponding to each included NCS practice and cropping system.

Table 24. Baseline and NCS emissions factor reduction estimate for major
                     crops applicable NCS practices.
------------------------------------------------------------------------
                        Emissions  factor  (Mg
         Crop              CO2e ac	1 yr	1)           Citation/Notes
------------------------------------------------------------------------
                             Baseline values
------------------------------------------------------------------------
Potato                                    2.11  Poore & Nemecek, 2018
Lowbush blueberry                         0.32  Percival & Dias, 2014
Wheat                                     0.47  Adom, et al., 2012
Corn grown for silage                     0.66  Adom, et al., 2012
Barley                               \27\ 0.47  Adom, et al., 2012
\27\ Assuming the
 same emissions for
 growing barley as a
 rotation crop as
 winter wheat for
 animal feed, due to
 similarities in
 equipment use and
 nitrogen fertility;
 Beegle, D. (2017).
 Estimating Manure
 Application Rates
 [University]. Penn
 State Extension.
 https://
 extension.psu.edu/
 estimating-manure-
 application-rates.
Vegetables                                2.21  Poore & Nemecek, 2018
Apples                                    2.23  Poore & Nemecek, 2018;
                                                 Karlsson, 2017
------------------------------------------------------------------------
                Reduction due to NCS practice application
------------------------------------------------------------------------
Change to NT from                         0.46  USDA COMET Planner
 intensive tillage                               (Swan, et al., 2020)
Change to NT from RT                      0.36  USDA COMET Planner
Change to RT from                         0.10  USDA COMET Planner
 intensive tillage
Use of cover crop                         0.13  USDA COMET Planner
 (rye)
Use of cover crop                         0.23  USDA COMET Planner
 (red clover)
Use of cover crop                         0.18  USDA COMET Planner
 (oats and peas mix)
Biochar application                   \28\ 1.6  Ciborowski, 2019
\28\ Assuming a one-
 time application of
 5.9 Mg/ac with
 benefits for 20
 years.
Amend with manure                         0.16  USDA COMET Planner
Convert to permanent                      1.29  Paustian, et al., 2019
 perennial grass set-
 aside
Permanent riparian                        1.69  National Council for Air
 border on marginal                              and Stream Improvement
 land                                            & U.S. Forest Service
                                                 Northern Research
                                                 Station, n.d.
------------------------------------------------------------------------


   Table 25. Baseline and NCS emissions factor reduction estimates for
                   dairy manure management practices.
------------------------------------------------------------------------
                             Emissions factor
   Manure management       factor  (tCO2e cow	1       Citation/Notes
        practice                  yr	1)
------------------------------------------------------------------------
                             Baseline value
------------------------------------------------------------------------
One dairy cow                               6.19  Maine DEP \29\
------------------------------------------------------------------------
                Reduction due to NCS practice application
------------------------------------------------------------------------
Large (up to 2,500                          4.96  AgSTAR Livestock
 cows) Complete Mix                                Anaerobic Digester
 Anaerobic Digester                                Database (EPA, 2020),
 with electricity                                  median value of
 generation                                        applicable digesters
                                                   located in northern
                                                   states \30\
\29\ Unpublished data
 obtained through
 personal communication
 with Maine Department
 of Environmental
 Protection, July 2020.
Covered Lagoon/Holding                      6.99  AgSTAR Livestock
 Pond Anaerobic                                    Anaerobic Digester
 Digester                                          Databas[e], mean of
                                                   applicable digesters
                                                   located in northern
                                                   states
\30\ We included in
 this analysis data
 from any digester in a
 northern state using
 dairy manure as a
 primary animal/farm
 type, with size
 limited to digesters
 serving a maximum of
 10,000 head of dairy
 cows. Northern states
 included CT, IA, ID,
 IL, IN, MA, ME, MI,
 MN, NE, MT, NY, OH,
 OR, PA, SD, VT, WA,
 WI, and WY. No data
 were available for ND,
 NH, NJ, and RI, which
 would otherwise have
 been considered
 applicable. Median
 values are reported in
 some cases to avoid
 biases in mean
 estimates resulting
 from skewed data
 distributions.
Soild-liquid separation                     8.16  (ICF International,
 (SLS)                                             2013)
Small (300 cows)                            4.96  AgSTAR Livestock
 Complete Mix Anaerobic                            Anaerobic Digester
 digester with                                     Database, median
 electricity generation                            value of applicable
                                                   digesters located in
                                                   northern states
Plug Flow Anaerobic                         4.29  AgSTAR Livestock
 digester with                                     Anaerobic Digester
 electricity generation                            Database, median
                                                   value of applicable
                                                   digesters located in
                                                   northern states
------------------------------------------------------------------------


 Table 26. Input assumptions for Maine dairy manure management practices. Estimates are based on data published
  in the EPA AgSTAR Database (EPA, 2020), ICF (2013), and USDA EQIP Cost Sheets (Maine Payment Schedules, 2020;
                                                USDA NRCS, 2014).
----------------------------------------------------------------------------------------------------------------
                             Large  complete                                    Small  complete     Plug flow
                              mix  anaerobic  Covered  lagoon/   Solid-liquid    mix  anaerobic     anaerobic
          Estimate            digester with     holding pond      separation     digester with    digester with
                               electricity       anaerobic          (SLS)         electricity      electricity
                                generation        digester                         generation       generation
----------------------------------------------------------------------------------------------------------------
Farm herd size (dairy cows)            2,500              300            1,000              300              300
GHG mitigated per farm                16,000            2,097            8,162            1,920            2,883
 (tCO2e/yr)
GHG mitigated per cow                   4.96             6.99             8.16             4.96             4.29
 (tCO2e/head/yr)
Annualized Capital Costs ($/         $96,564          $72,793          $34,894          $49,545          $75,983
 yr)
Operations and Maintenance          $158,136          $33,557          $27,309          $24,697          $37,877
 Cost ($/yr)
Energy Sold ($/yr)                  $177,848          $13,054               $0          $21,342          $21,342
                            ------------------------------------------------------------------------------------
  Total Cost Less Energy ($          $76,852          $93,296          $62,203          $52,901          $92,519
   farm/yr)
  Total Cost Less Energy ($              $31             $311              $62             $176             $308
   cow/yr)
----------------------------------------------------------------------------------------------------------------

No-till cropping (NT)
    No-till cropping practices address the amount, orientation,\31\ and 
distribution of crop and other plant residue on the soil surface year-
round. Crops are planted and grown in narrow slots or tilled strips 
established in the untilled seedbed of the previous crop (Residue and 
Tillage Management, No Till, 2016). This practice includes maintaining 
most of the crop residue on the soil surface throughout the year, 
commonly referred to as no-till. The common characteristic of this 
practice is that the only tillage performed is a very narrow strip 
prepared by coulters, sweeps, or similar devices attached to the front 
of the planter.
---------------------------------------------------------------------------
    \31\ Orientation refers to the direction that crops are planted in 
a field, and can vary based on slope and direction.
---------------------------------------------------------------------------
    Benefits to soil include increasing organic matter, improving soil 
tilth, and increasing productivity as the constant supply of organic 
material left on the soil surface and in the soils as roots is 
decomposed by a healthy population of earthworms and other soil macro- 
and microorganisms. Operations and maintenance for this practice 
includes evaluating the crop-residue cover and orientation for each 
crop to ensure the planned amounts, orientation, and benefits are being 
achieved. Weeds and other pests must be monitored to ensure pest 
populations do not exceed thresholds.
    According to the 2017 USDA NASS Census of Agriculture, there were 
21,676 acres of cropland in Maine reported to be implementing no-
tillage practices, or 14% of all 152,796 acres of cropland in Maine 
that reported their tillage practices. For context, the USDA NASS 
Census of Agriculture found that Maine has a total of 472,508 acres of 
cropland, indicating that only 32% of the total crop area in the state 
reported any type of tilling practice (2017 Census of Agriculture, 
2019). As a result, additional inference may need to be made to 
allocate tillage practices to the other 68% of cropland in the state, 
of which most could be no till (e.g., blueberries, hay, etc.).
Reduced-till cropping (RT)
    Reduced-till practice manages the amount, orientation, and 
distribution of crop and other plant residue on the soil surface and in 
the soils as roots year-round while limiting the soil-disturbing 
activities used to grow and harvest crops in systems where the field 
surface is tilled prior to planting (Residue and Tillage Management, 
Reduced Till, 2016). This practice includes tillage methods commonly 
referred to as mulch tillage where a majority of the soil surface is 
disturbed by non-inversion tillage operations such as vertical tillage, 
chiseling, and disking, and also includes tillage/planting systems with 
relatively minimal soil disturbance. Mulch tillage includes the uniform 
spreading of residue on the soil surface; planning the number, 
sequence, and timing of tillage operations to achieve the prescribed 
amount of surface residue needed; and using planting equipment designed 
to operate in high residue situations.
    RT cropping practice improves soil health by increasing organic 
matter, improving soil tilth, and increasing productivity as the 
constant supply of organic material left on the soil surface and in the 
soil is decomposed by a healthy population of earthworms and other soil 
macro- and microorganisms. Operations and maintenance for this practice 
includes evaluating the crop residue cover and orientation for each 
crop to ensure the planned amounts, orientation, and benefits are being 
achieved.
    According to the 2017 USDA NASS Census of Agriculture, there were 
31,953 acres of cropland in Maine reported to be implementing reduced-
tillage (but not no-till) practices, or about 20% of farmed acres in 
Maine with reported tillage practices (2017 Census of Agriculture, 
2019).
Cover cropping
    Cover cropping is growing a crop of grass, small grain, or legumes 
primarily for seasonal protection and soil improvement (Cover Crop, 
2014). This practice is used to control erosion, add fertility and 
organic material to the soil, improve soil tilth, increase infiltration 
and aeration of the soil, and improve overall soil health. The practice 
is also used to increase populations of bees for pollination purposes. 
Cover and green manure crops have beneficial effects on water quantity 
and quality. Cover crops have a filtering effect on movement of 
sediment, pathogens, and dissolved and sediment-attached pollutants.
    Operation and maintenance of cover crops include: controlling weeds 
by mowing or by using other pest management techniques, and managing 
for the efficient use of soil moisture by selecting water-efficient 
plant species and terminating the cover crop before excessive 
transpiration. Use of the cover crop as a green manure crop to recycle 
nutrients will impact when to terminate the cover crop to match the 
timing of the release of nutrients from the decomposing biomass with 
uptake by the following cash crop.
    Cover crops can generate a variety of benefits and costs, both 
internal and external to the farm. The net effect of these impacts on 
farm-level profitability is a function of many factors and in a given 
case may be either negative or positive, though appropriate selection 
of cover cropping design can dramatically reduce the likelihood of 
negative outcomes (Clark & Sustainable Agriculture Research & Education 
Program, 2007).
    According to the 2017 USDA NASS Census of Agriculture, there were 
55,462 acres of cropland in Maine reported to be implementing cover 
cropping, or 12% of all acres of cropland in Maine (2017 Census of 
Agriculture, 2019).
Biochar Amendments
    Biochar is a substance similar to charcoal, which can be used as a 
soil or growing media amendment. It is typically produced from biomass 
using pyrolysis technology where oxygen is either absent or depleted 
(K. Paustian, 2014). The pyrolysis process produces biochar as well as 
two additional materials, syngas and bio-oil that may have commercial 
value as energy sources. Biochars differ depending on the feedstock 
(starting material), temperature, and residence time. A wide variety of 
feedstocks can be used depending on location, cost, and availability.
    Biochars have utility as a tool for waste management and soil 
remediation. Biochars may also mitigate greenhouse gas (GHG) emissions 
through carbon sequestration. Biochar addition to agricultural soils 
has gained much recognition in the last decade because it can have 
positive effects on crop yield and soil nutrient stocks, among other 
parameters (Ding, et al., 2016). It should be noted, however, that 
yield improvements are not universal, and based on current data, are 
not expected in for our climate in major crops or systems including 
potato-grain (Jay, et al., 2015), corn (Aller, et al., 2018; Novak, et 
al., 2019), orchards (Khorram, et al., 2019; von Glisczynski, et al., 
2016), and vegetables (Jeffery, et al., 2017).
    A number of studies and reviews have highlighted the potential 
benefits of utilizing biochar as a soil amendment. These have covered 
issues such as mitigation of global warming through application of 
stable carbon into soil, waste management, bioenergy production, soil 
health, and productivity (Kookana, et al., 2011). However, full 
lifecycle assessments that include the effects of biochar amendment on 
non-CO2 trace gasses and soil nutrient fluxes are few 
(Gurwick, et al., 2013) and not necessarily applicable to our growing 
system. Perhaps the most relevant estimate for our systems comes from a 
Minnesota Pollution Control Agency report, which used a literature 
review approach to account for direct and indirect nitrous oxide 
emissions, methane sink removals, soil organic carbon, and greenhouse 
gasses from field removal and transit, calculating that biochar amended 
soils at a one-time application rate of 15 Mg ha-1 would 
sequester 0.85 Mg C ha-1 year-1.\32\ This value 
is in line with prior literature, which indicates a broad range of 
sequestration values from 0.2 to 5.3 Mg C ha-1 
year-1 (Eagle, et al., 2013; Woolf, et al., 2010). While 
this Minnesota estimate represents a useful starting place for the 
present analysis, it should be stressed given the range of possible 
outcomes and number of variables to consider that field studies 
conducted in local soils, using biochar from locally applicable 
feedstocks, are greatly needed to verify applicability of literature 
estimates to our system and provide additional data. (Gurwick, et al., 
2013). The assumption of a one-time application with results annualized 
over 20 years is in line with how commercial-scale farmers might 
implement this practice in Maine.\33\
---------------------------------------------------------------------------
    \32\ P. Ciborwski, personal communication, June 16, 2020.
    \33\ J. Jemison, personal communication, Spring 2020.
---------------------------------------------------------------------------
    Most studies using biochars as soil amendments show that biochar 
can increase soil productivity, but some show decreased productivity 
(Maguire & Agblevor, 2010). This is likely due to the wide variety of 
biochars that can be produced and the variability among soils and 
cropping systems. Biochar can increase soil productivity through the 
application of nutrients (for some biochars and some nutrients), a 
liming effect for alkaline biochars, and through improvements in soil 
properties that includes aeration, moisture retention, and improved 
soil structure. Most minerals present in the feedstock are concentrated 
in the biochars produced, but much of the nitrogen and sulfur is lost 
during pyrolysis. Therefore, supplemental nitrogen will generally be 
needed when using biochars as a soil amendment. Wood biochars, for 
which locally available feedstock is abundant in Maine, often have 
particularly low nutrient concentrations.
    Biochar can be applied by hand, or using widely available equipment 
including broadcast seeders and lime or manure spreaders at larger 
scales. To increase efficiency by limiting the number of field 
operations needed, biochar can be mixed with other amendments including 
lime and liquid manure prior to application. Biochar can be applied as 
a topdress amendment, broadcast and incorporated through subsequent 
tillage, or applied in surface or sub-surface bands. A potential 
tradeoff to consider is that biochar, especially when surface-applied 
in no-till or reduced-tillage systems, can bind to and diminish 
herbicide efficacy (Major, 2010). Additional research is needed to 
suggest tailored application rates most applicable to growing contexts 
in Maine.
    It is unknown how many farmers in Maine are currently incorporating 
biochar into their farm systems. There is no centralized reporting 
system for biochar use, and some farmers produce their own biochar from 
their woodlots. However the overall figure for Maine at this time is 
likely to be very small.
Manure Management
    Large dairy and hog farms with manure lagoons emit significant 
amounts of methane (CH4), a potent greenhouse gas that can 
be mitigated through a suite of practices, including changes to 
agricultural land management. Manure management--how manure is 
captured, stored, treated, and used--has important implications for 
farm productivity and the environment (Manure Management, 2020). For 
context, about 88% of CH4 emissions from livestock manure 
management in the US are generated from dairy (56%) and swine farms 
(32%) (Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2017, 
Chapter 5, Table 5-6, 2019). When applied according to the agronomic 
needs of crops, manure can improve productivity by reducing the need 
for commercial fertilizer while enhancing soil health. Manure 
management can also affect water quality primarily by leaching 
nutrients (e.g., nitrogen and phosphorus) to groundwater and runoff 
resulting in eutrophication.
    A single dairy cow weighs approximately 1,400 lbs and produces 
approximately 80 lbs of recoverable manure per day per 1,000 lbs of 
animal unit (Animal Manure Management, 1995), which works out to 112 
lbs of recoverable manure per dairy cow per day. This translates to 
40,880 lbs, or 18.5 metric tons, of manure produced per cow on an 
annual basis. On average, dairy manure produces about 0.023 m\3\ of 
methane per kilogram of manure (0.37\3\ per lb) on a wet basis 
(Aguirre-Villegas, et al., 2016), which translates to 15,126\3\ of 
methane per cow per year, or approximately 6 lbs of CO2-
equivalent per year.
    Most methane associated with manure is emitted during storage 
(Fangueiro, et al., 2008). Maine farmers must store manure over the 
winter months because they are prohibited from spreading manure at that 
time (Winter Spreading of Manure, 2003). There are a number of manure 
management practices that can be employed to mitigate GHG emissions. 
These include placing impermeable covers on lagoons and liquid/slurry 
ponds; adding a solids separator to lagoon systems, which can reduce 
emissions by 19% or more (Aguirre-Villegas, et al., 2016; Fangueiro, et 
al., 2008); and adopting an anaerobic digester system (e.g., a covered 
lagoon, complete mix, or plug flow system), which can reduce emissions 
by approximately 60% (Aguirre-Villegas, et al., 2016; Amon, 
Kryvoruchko, Amon, et al., 2006; Amon, Kryvoruchko, Moitzi, et al., 
2006). Farmers who install an anaerobic digester on their livestock 
operations can use manure to produce a biogas that can be burned to 
generate electricity. Digesters can also reduce greenhouse gas 
emissions from manure storage and handling. The size of the digester 
will vary by the area being managed and can range from farm- to 
community-scale. For example, Summit Energy announced in May 2019 that 
they will construct a $20 million digester in Clinton, Maine, that will 
utilize waste from five dairy farms that make up 17% of the state's 
dairy production, and the company claims this will generate about 
125,000 MMBtu of gas per year (Summit Utilities Inc., 2019).
    To our knowledge, only one Maine dairy farm currently utilizes as 
anaerobic digester for manure management, the Fogler Dairy Farm in 
Exeter (Stonyvale Farm (Fogler Farm) Anaeorobic Digester System, n.d.). 
Other mitigation systems have varying applicability in Maine, depending 
on the size of the herd, which has implications for installment costs, 
and on the challenges posed by Maine's cold climate (ICF International, 
2013). For example, freezing temperatures can impair the functioning of 
solids separators or inhibit the production of methane in digesters.
Manure Amendments
    Manure used as a soil amendment can act as a fertilizer and can 
also improve the physical qualities of the soil including tilth, water 
infiltration and retention, and soil porosity (Risse, et al., 2006). 
Most of these physical improvements are linked to an increase in soil 
organic matter. The addition of manure to soil can increase carbon 
sequestration (Koga & Tsuji, 2009), but it also increases nitrous oxide 
emissions (a potent greenhouse gas), especially when it is injected 
into soils rather than broadcast (Adair, et al., 2019; Dittmer, 2018; 
Duncan, et al., 2017). Increased carbon sequestration due to manure 
application may be offset by increased nitrous oxide emissions, at 
least on a global aggregate scale (Zhou, et al., 2017). Thus, the 
environmental benefits of manure as a soil amendment may not include a 
reduction in greenhouse gas emissions. Nonetheless, the potential for 
manure amendment to reduce dependency on chemical fertilizers, use of a 
byproduct of animal production that would otherwise be considered 
waste, and increase climate resilience through improvements to soil 
health are important benefits from this practice that warrant 
consideration.
    Manure amendment can help supply crop nutrient demand, but its 
nutrient composition varies (Brown, 2015; Chastain & Camberato, 2003). 
The average proportion of nitrogen-phosphorus-potassium in dairy manure 
is 11, 7, and 9 lbs per ton on a dry matter basis (Wilson, 2020). In 
general, plants require much more nitrogen than either phosphorus or 
potassium, and so applying manure to meet plant nitrogen needs will 
oversupply phosphorous and sometimes potassium. Further, most nitrogen 
in manure is stored in organic forms that are not plant-available and 
must be converted to inorganic forms through microbial processes 
influenced by the (carbon:nitrogen) ratio of the manure. The resulting 
variable rate of nutrient release makes timing manure application to 
coincide with plant fertility needs a challenge. The composition of the 
manure, nutritional demands of the crop, and the nutrient content and 
cropping history of the soil are all important considerations in 
determining amendment rates (Beegle, 2017; Koehler, 2020). 
Overapplication of fertility can result in negative consequences for 
water (Wilson, 2020) and air quality (Duncan, et al., 2017).
    Manure application methods vary depending on the liquid content of 
the manure. Both solid and liquid manure can be broadcast onto the 
surface of a field (and may be incorporated), while liquid manure can 
be injected (Rausch & Tyson, 2019; University of Minnesota Extension, 
2018). Broadcasting solid or semi-solid manure with a spreader is 
perhaps the oldest and simplest method of application. Liquid manure is 
applied using liquid manure tankers pulled behind a tractor or mounted 
on a truck. Liquid manure can also be broadcast using irrigation 
equipment, either by sprinkler irrigation or by a draghose, tractor-
mounted irrigation system (Rausch & Tyson, 2019). A drawback to the 
broadcasting method is the potential loss of inorganic and plant-
available nitrogen to volatilization. This loss can be mitigated by 
incorporating the manure into the soil. Manure can be incorporated 
immediately upon broadcast or within a few days; the more quickly it is 
incorporated, the less ammonia is released to the atmosphere.
    The injection method for liquid manure was developed to reduce 
odors and other issues related to the release of ammonia following the 
broadcasting of manure. It is also compatible with no-till systems. 
There are three injection methods: knife injection, in which vertical 
blades create 6-8" vertical grooves that collect manure; sweep 
injection, which places a broad, horizontal band of manure underneath 
the surface soil; and disk or coulter injection, which uses a rolling 
disk or a coulter to create a vertical groove that collects manure 
(University of Minnesota Extension, 2018). Injection of manure greatly 
reduces ammonia volatilization, in some cases by nearly 100%, but it 
can increase nitrous oxide emissions by up to 152% (Dittmer, 2018; 
Zhou, et al., 2017) and additionally result in increased nitrous oxide 
fluxes during winter freeze-thaw events (Adair, et al., 2019).
    Three factors that influence the cost of manure management are 
loading, transporting, and application. Each may require specialized 
equipment and have its own constraints. For example, loading is 
constrained to time periods when animals are not present (except in the 
case of an external storage structure). Transportation costs are 
influenced by the distance traveled, hauling capacity, and travel 
speed. Application is constrained by soil and plant conditions and 
requires specialized equipment (University of Minnesota Extension, 
2018).
    Manure may be stored, transported, and applied in three forms: 
solid, liquid and slurry. Solid manure is cheaper to transport due to 
its lower water content, and therefore can be transported farther. 
Liquid and slurry manure have the lowest loading costs, but they have 
high transport costs. Liquid manure, despite its high transport cost, 
is the cheapest to apply, especially when existing irrigation equipment 
is modified to broadcast manure (Massey & Payne, 2019). In general, 
manure is expensive to transport, and especially when it has a high 
liquid content; thus there are important economic tradeoffs between 
type of manure and hauling distance (Harrigan, 2001, 2011; Risse, et 
al., 2006). A study of manure application in New York suggested that on 
average, farms were able to apply just under 240,000 gallons of liquid 
manure in a 10 hour day to fields that were on average 3.5 miles away. 
On average, about 15,000 gallons of manure were spread per application 
hour--approximately the amount required to supply one acre of corn with 
its total nitrogen needs for the growing season, if the manure is 
incorporated. On average, the estimated total annual cost of manure 
application was $105,000, or about $134 per cow (Howland & Karszes, 
2012). Because it requires specialized equipment and more time to 
apply, injection is somewhat costlier than broadcasting (Hanchar, 
2014), though one study indicated it only increased the cost by about 
6% compared to broadcast application plus incorporation (Hadrich, et 
al., 2010).
Crop and grassland conservation
    Marginal cropland and pasture is often not profitable to farm in 
many years. As such, some farmers voluntarily retire cropland utilizing 
rental payments or easements. For example, the national Conservation 
Reserve Program (CRP) provides a yearly rental payment if farmers 
enrolled in the program agree to remove environmentally sensitive land 
from agricultural production and plant species that will improve 
environmental health and quality (Farm Service Agency, 2019). Contracts 
for land enrolled in the CRP are typically 10-15 years in length. The 
long-term goal of the program is to reestablish valuable land cover to 
help improve water quality, prevent soil erosion, and enhance wildlife 
habitat. Changes in vegetation and reduced soil disturbance are also 
likely to increase carbon sequestration and/or reduce GHG emissions as 
land is taken out of production.
    According to the USDA, there were 7,744 acres in Maine enrolled in 
the Conservation Reserve Program as of September 30, 2017 (Farm Service 
Agency, 2017). These lands received a mean rental payment of $38/acre/
yr for cropland and $18/acre/yr for grassland (Farm Service Agency, 
2018). These values are relatively low compared to other parts of the 
US, indicating that there are limited opportunity costs of setting 
aside marginal land in Maine.
    Additionally, the 2017 USDA Census of Agriculture reported that 484 
farms in Maine had a conservation easement totaling 36,274 acres (2017 
Census of Agriculture, 2019).
Riparian Buffer
    Riparian buffers are vegetated areas adjacent to streams that 
differ from their surrounding land practices (i.e., agriculture or 
forest land). In agricultural lands this usually involves planting 
trees, shrubs, and grasses 35 to 100 away from the stream boundary. 
Most literature suggests a three-stage approach to planting buffers 
(Dybala, et al., 2019). The first zone closest to the stream should 
consist of large woody trees and shrubs that have traditionally 
coevolved with streams to withstand flooding. This zone provides 
aquatic shade, streambank stability, and dead wood and leaf litter 
nutrients for the stream. Zone 2 filters runoff and absorbs water borne 
pathogens/nutrients. It has similar vegetation as Zone 1 as it is 
mostly trees and shrubs. This zone can have larger trees with smaller 
trees and shrubs beneath. This zone can also be used for commercial 
harvest of non-traditional agriculture and commercial tree species like 
Christmas trees, nut crops, shade loving wildflowers, ginseng, red oak, 
and sugar maple. Zone 3 filters water and slows down runoff. This zone 
should consist of tall grasses and is the last zone adjacent to working 
cropland and pastureland.
    Riparian buffers in agricultural land have large potential benefits 
for landowners and downstream communities. Riparian zones have a 
relatively large carbon sequestration potential that can also offset 
emissions from traditional agricultural practices. Furthermore, they 
filter nutrients and collect sediments, which can improve water quality 
(Zhang, et al., 2010). Riparian buffers can also provide local habitat 
and biodiversity benefits.
    Key costs to implement riparian buffers include planting, 
maintenance, and opportunity costs. Agricultural land directly adjacent 
to waterways is often less productive then the landowner's average 
farmland so the opportunity cost of retiring crop land is typically 
lower in buffer zones relative to the most productive areas of the farm 
(Daigneault, et al., 2017). There is estimated to be approximately 
21,000 acres of potential riparian buffer zone land in Maine 
agriculture (Cook-Patton, et al., 2020). The costs of implementing 
riparian buffers in Maine are listed in Table 27.

                Table 27. Detailed riparian buffer costs
------------------------------------------------------------------------
            Item                   Min            Med            Max
------------------------------------------------------------------------
                       Establishment Costs ($/ac)
First 2/3 Stages of Trees and Shrubs, tree dominated buffer. Assumed 80%
                           trees, 20% shrubs.
------------------------------------------------------------------------
             Tree Saplings         $386.49        $463.78        $541.08
            Shrub Saplings          $91.67        $110.00        $128.33
                     Tree Labor + M$297.30helters $356.76        $416.22
                    Shrub Labor + Ma$61.94         $74.32         $86.71
                   Shelters
       Tree shelter + mats         $594.59        $713.51        $832.43
                Shrub mats          $61.94         $74.32         $86.71
 Shipping and Handling for          $49.55         $59.46         $69.37
              tree mats and
                  shelters
 Shipping and Handling for           $4.95          $5.95          $6.94
                 Shrub mats
                             -------------------------------------------
  Total Stage 1 and 2            $1,548.42      $1,858.11      $2,167.79
   Establishment Cost.......
------------------------------------------------------------------------
                           3rd stage, grasses.
------------------------------------------------------------------------
                  Planting           $5.23         $42.23         $79.24
                     Seeds          $52.30        $204.44        $356.58
          Site Preparation           $9.41         $36.40         $63.39
               Fertilizer/Lime      $15.69         $47.46         $79.24
       Mowing or Herbicide           $5.23         $50.16         $95.09
                             -------------------------------------------
  Total Stage 3                     $87.86        $380.70        $673.53
   Establishment Cost.......
------------------------------------------------------------------------
                        Total Establishment Cost
------------------------------------------------------------------------
         Stage 1, 2, and 3       $1,636.28      $2,238.81      $2,841.33
         Establishment Cost
------------------------------------------------------------------------
                        Maintenance Costs ($/ac)
------------------------------------------------------------------------
  Replanting (assuming 80%          $58.57         $81.58        $104.60
             survival rate)
 Stage 1 & 2 Mowing and/or          $39.64         $79.28        $118.92
                  Herbicide
            Stage 3 Mowing           $6.28         $18.83         $31.38
         Stage 1, 2, and 3         $104.49        $179.69        $254.89
           Maintenance Cost
------------------------------------------------------------------------
                Total Riparian Buffer Costs and Benefits
------------------------------------------------------------------------
Total Riparian Buffer Cost       $1,740.77      $2,418.50      $3,096.22
                     ($/ac)
  Annualized Costs over 20         $139.68        $194.07        $248.45
          years ($/ac/yr) *
                             -------------------------------------------
     Annual Average Carbon            1.23           1.69           2.13
              Sequestration
             (tCO2e/ac/yr)
Break-Even Carbon Price ($/           $114           $115           $117
                     tCO2e)
------------------------------------------------------------------------
* Costs annualized over 20 years using a discount rate of 5%.


     Table 28. Range of agricultural NCS GHG mitigation factors from
                       literature (tCO2e/ac/yr) *
------------------------------------------------------------------------
        NCS Practice               Min          Median *         Max
------------------------------------------------------------------------
    No-till from Intensive            0.01           0.46           0.89
      No-till from Reduced            0.00           0.36           0.70
           Reduced tillage            0.00           0.10           0.19
               Cover Crops           ^0.15           0.18           1.06
                   Biochar            1.10           1.60           2.82
            Amend w/Manure           ^0.13           0.16           0.60
      Convert to Perennial            0.65           2.31           3.47
           Riparian Buffer            1.74           2.20           2.64
   Dairy Manure Management            1.94           4.73          6.68
------------------------------------------------------------------------
* Only median (medium) values were used for this analysis.

Appendix C. Statewide extrapolation of forest carbon estimates
    To incorporate the potential additive effects of the current forest 
carbon stock and future forest growth in areas outside our project 
study area we used US Forest Service Inventory and Analysis plot data 
to estimate (1) live forest carbon ca. 2010, and (2) average 10 year 
change in forest carbon. The live forest carbon ca. 2010 was 177 MMTC 
and the average 10 year change was 23.6 MMTC/yr based on all 1,700 
plots outside our project study area. We added these values to the 
simulated predictions for our study area to derive a statewide estimate 
of total aboveground forest carbon 2010-2070 (Figure 20). It is 
important to note that using this process, implicitly assumes no change 
in forest management on commercial forestlands outside our project 
study area, nor accounts for the potential effects of climate change on 
forest productivity.
Figure 20. 


          Total forest carbon stock (MMTC) for all of Maine, including 
        7.5 million acres outside of the Landis model study area, 
        modeled from 2010 to 2070.

 
 
 
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          Inside cover: Howland Research Forest, Dave Hollinger, USDA 
        Forest Service.

          Partners in this United States Climate Alliance project are 
        the State of Maine Governor's Office of Policy Innovation and 
        the Future; the U.S. Department of Agriculture Climate Hub; the 
        Northern Institute of Applied Climate Science; The Nature 
        Conservancy in Maine; Maine Farmland Trust; Maine Climate 
        Table; American Farmland Trust; and Wolfe's Neck Center of 
        Agriculture & the Environment.
          Funding support for this project was provided by the Doris 
        Duke Charitable Foundation, Maine Farmland Trust, and the 
        Senator George J. Mitchell Center for Sustainability Solutions.
          crsf.umaine.edu/forest-climate-change-initiative/ncs
                                 ______
                                 
Submitted Statement by Hon. Cheri Bustos, a Representative in Congress 
                             from Illinois
[https://bustos.house.gov/wp-content/uploads/2019/08/Rural-Green-
Partnership-1.pdf]

[August 6, 2019]
Combatting Climate Change: An Opportunity for Rural America *
---------------------------------------------------------------------------
    * Editor's note: there is an accompanying news release (https://
bustos.house.gov/bustos-announces-rural-green-partnership-to-combat-
climate-change-and-spur-economic-growth/) and video (https://
www.dropbox.com/s/t9tmc1votajbnrj/Rural%20Green_1.mp4?dl=0) that have 
been retained in Committee file.
---------------------------------------------------------------------------
    From agriculture to outdoor recreation, rural economies across the 
United States depend on a stable climate and consistent weather 
patterns. Combatting climate change is both a necessity in rural 
America and also an opportunity to reverse the economic headwinds which 
are widening the gap between rural communities and their urban 
counterparts. The unique opportunities for rural America stem from its 
vast land resources: 71% of U.S. territory (excluding Alaska) is 
privately-owned rural land \1\ where carbon can be sequestered in 
soils, vegetation and forests; where biobased and renewable products--
fuels, plastics and other renewable materials--can be grown and 
produced; where captured carbon dioxide can be stored deep underground 
or utilized in other ways; where wind farms and solar fields can be 
built on a large scale; and where a plethora of technical training 
schools like community colleges, tribal colleges, land-grant 
universities, union-registered apprenticeship programs and technical 
training colleges can prepare workforces that will grow rural economies 
while addressing climate change.
---------------------------------------------------------------------------
    \1\ USDA, NRCS National Resources Inventory Summary Report, 
September, 2018, p. 2-1.
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Goal
    To capitalize on these opportunities, we propose a Rural Green 
Partnership--a set of policies that work with Federal, local and state 
governments, local businesses, unions, producers, NGOs and other 
stakeholders to lower greenhouse gas (GHG) emissions in every economic 
sector of rural America and spur economic growth.
Rural Green Partnership Framework
    Five principles will guide Rural Green Partnership climate 
policies:

  (1)  Expand and improve conservation programs that are respected and 
            well known to farmers, and explore new markets for 
            ecosystem services that establish economic incentives to 
            adopt conservation practices that increase resilience, 
            sequester more carbon in soil, crops and forests, prevent 
            erosion and can be scaled up quickly and efficiently.

  (2)  Invest in rural infrastructure that will form the foundation of 
            new green economic growth: including faster broadband 
            speeds so farmers can take advantage of GPS for precision 
            agriculture, an expanded grid, green infrastructure and 
            carbon dioxide pipelines to transport captured carbon to 
            locations where it can be stored or utilized.

  (3)  Leverage zero and low interest loans, tax credits and grants to 
            incentivize new clean energy development and innovations 
            that drive down GHG emissions.

  (4)  Increase basic and applied research funding for farming 
            practices and sustainable land uses, clean energy 
            technologies, energy storage, energy efficiency and carbon 
            dioxide capture, storage and utilization as well as 
            extension efforts and technical assistance to ensure that 
            government research outcomes are transferred effectively to 
            stakeholders.

  (5)  Foster green workforce development at union and registered 
            apprenticeship programs, community colleges, tribal 
            colleges, technical training centers and other colleges and 
            universities across rural America.
Rural Green Partnership Policies
    The following sections outline policies to reduce GHG and increase 
clean energy opportunities in rural America across the five economic 
sectors that comprise total U.S. emissions: \2\ * agriculture, 
electricity, transportation, commercial & residential and industry. 
Policies will also increase carbon dioxide removals via land use and 
forestry practices.
---------------------------------------------------------------------------
    \2\ Data on greenhouse gas emissions by sector from EPA: https://
www.epa.gov/ghgemissions/sources-greenhouse-gas-emissions.
    * Editor's note: the footnote reference ``2'' should have been set 
as an endnote as it is used multiple times in this document.
---------------------------------------------------------------------------
Agriculture, Land Use and Forestry
    Agriculture contributes 9% of U.S. GHG emissions \2\--the least of 
all economic sectors. In the last 30 years, however, land use and 
forestry (LUF) activities in the United States have removed greater 
amounts of carbon dioxide from the atmosphere than they have generated. 
In 2017, for example, LUF offset nearly 11% of total U.S. GHG 
emissions.\3\ Moreover, the largest and most cost-effective potential 
sink for drawing down significant carbon dioxide emissions still 
remains the nation's soils and forests--rural America's greatest asset. 
Rural Green Partnership policies for agriculture will therefore focus 
on increasing soil organic carbon through soil health strategies that 
help farmers and ranchers manage risk by increasing long-term 
resiliency and adaptation to proliferating extreme weather events. For 
forestry, Rural Green Partnership policies will rely on sustainable 
management, reforestation and uses of forest products. Specifically, 
the Rural Green Partnership will:
---------------------------------------------------------------------------
    \3\ EPA Inventory of U.S. Greenhouse Gas Emissions and Sinks: 
https://www.epa.gov/ghgemissions/sources-greenhouse-gas-emissions.

   Increase funding and number of acres available for Federal 
        assistance to incentivize adoption and maintenance of proven, 
        science-based, precision agriculture and conservation 
        management farming practices that increase soil carbon, reduce 
        runoff and optimize fertilizer inputs as part of systemic farm 
        management. This work can be done through existing Natural 
        Resources Conservation Service (NRCS), Farm Service Agency 
        (FSA), other Federal programs or re-envisioned Federal 
---------------------------------------------------------------------------
        assistance.

   Expand the number and availability of conservation technical 
        experts capable of offering customized, one-on-one conservation 
        advice to agricultural producers.

   Streamline the process to sign up for NRCS/FSA programs.

   Facilitate widespread data collection to aid hyper-localized 
        management strategies that increase carbon sequestration and 
        increase resilience for the various geographies in the U.S.

   Incentivize integrated crop/livestock operations to maximize 
        the soil carbon sequestered in croplands.

   Expand grants, loans and tax incentives for farm and ranch 
        operations that improve energy efficiency, energy generation 
        and drive down GHG emissions through technologies like methane 
        digestors.

   Increase applied agricultural R&D (research and development) 
        for crop breeding, precision agriculture, soil health 
        practices, extension yield trials, and other on-farm 
        conservation research that mitigates risk and increases 
        resilience.

   Guarantee broadband access for farms, homes and small 
        businesses to ensure that data related to best management 
        practices is readily available.

   Incentivize sustainable forestry practices that sequester 
        carbon while creating new markets for biomass to heat and power 
        homes and business.

   Expand sustainable forestry practices such as pre-commercial 
        thinning, establishing forest stewardship plans and developing 
        fire resilient Wildland Urban Interfaces that reduce the 
        incidence and intensity of fires and CO2 emissions, 
        and further increase resources available for reforestation 
        after catastrophic loss.
Electricity
    The electricity sector comprises 28% of total U.S. annual GHG 
emissions. Despite this, 64% of U.S. electricity is generated from 
fossil fuels, while 19% comes from nuclear and 17% from renewables. 
Wind comprises just 7% of the total and solar a mere 1.6%. When 
accounting for GHG emissions, coal accounts for 27% of electrical 
production yet close to \2/3\ of carbon dioxide emissions. Rural Green 
Partnership policies for the electricity sector anticipate a future 
dominated by clean and net-zero energy that also works to reduce GHG 
emissions from fossil fuel sources. Policies for this sector will:

   Support the immediate and widescale deployment of carbon 
        capture, utilization and storage (CCUS) technologies on 
        existing fossil fuel energy facilities to significantly reduce 
        GHG emissions.

   Expand R&D for direct air capture (DAC) carbon dioxide 
        technologies that can be deployed in rural America.

   Expand R&D to overcome barriers to wider adoption for 
        intermittent renewables (including the integration of battery 
        storage) in order to further drive down costs.

   Ensure the continued safety and operation of the existing 
        nuclear fleet and the research, demonstration and deployment of 
        advanced nuclear reactors.

   Extend and increase renewable (solar, wind and biogas) tax 
        credits that enable rural businesses, including farms, to adopt 
        cleaner technologies, reduce costs and raise income.

   Invest in and support community colleges, tribal colleges, 
        technical schools, union and registered apprenticeship 
        programs, colleges and universities that engage in workforce 
        development programs for renewables and provide on-farm 
        assistance for renewable deployment.

   Make available investment tools to municipalities, 
        communities and extension services who form partnerships to 
        build and deploy renewables locally.

   Modernize and expand the electrical grid to facilitate the 
        greater utilization and deployment of renewable sources and 
        keep costs low for consumers.

   Provide assistance to rural municipalities and cooperatives 
        that are looking to bundle demand flexibility, energy 
        efficiency and rate design to ensure economic viability and 
        achieve GHG emissions.
Transportation
    At 29% of total U.S. GHG emissions,\2\ transportation is now the 
leading emitting sector. Light-duty vehicles account for 60% of 
emissions within transportation, while medium- and heavy-duty trucks 
account for 23% of the sector. To cut emissions and increase economic 
activity in rural America, the Rural Green Partnership focuses on the 
use of biofuels which have significantly lower lifecycle GHG emissions 
than gasoline and can save consumers money at the pump. For example, 
soybean biodiesel has a 57% reduction,\4\ and corn ethanol has a 19-48% 
reduced lifecycle GHG emissions compared to gasoline, with estimated 
reductions of approximately 70% when specific conservation practices 
are implemented. Moreover, increasing consumption of biofuels would 
increase stability for farmers while boosting rural economies and 
providing a catalyst for continuous economic sustainability. Targeted 
biofuels policies would:
---------------------------------------------------------------------------
    \4\ EPA Office of Transportation and Air Quality, July, 2016. 
https://www.epa.gov/sites/production/files/2016-07/documents/select-
ghg-results-table-v1.pdf.

   Expand use of biofuels (including ethanol, biodiesel, 
        advanced and other biofuels) that reduce GHG emissions by 
        strengthening, expanding or optimizing existing fuel standards 
        and/or creating new fuel standards (Renewable Fuel Standard, 
---------------------------------------------------------------------------
        High-Octane Fuel Standard, Low-Carbon Fuel Standard).

   Limit the expansive use of small refinery waivers that 
        undermine the Renewable Fuel Standard and increase GHG 
        emissions.

   Extend biodiesel and second-generation biofuel producer tax 
        credits.

   Incentivize land use practices, such as cover crops and no 
        till farming, to sequester more carbon, improve soil health and 
        further improve the lifecycle GHG benefits of biofuels.

   Create incentives for automobile manufacturers to produce 
        vehicles designed and warranted for higher blends of ethanol, 
        such as E30-E85 to help meet new efficiency and GHG emissions 
        reduction standards.

   Incentivize states to support fueling stations that install 
        E15 to E85 pumps.

    In addition, transportation policies should expand opportunities 
for electric vehicles (EV) and hybrid electric vehicles (HEV) in rural 
America. Because rural communities often generate significant business 
by providing service to interstate highway travelers (hotels, 
restaurants, gas stations), programs should not only focus on 
increasing U.S. EV sales (in 2017, these were still only a little over 
1% of total car sales), but also should assist rural businesses in 
installing EV charging infrastructure to facilitate interstate EV 
travel. To facilitate EV/HEV sales and infrastructure development, 
policies will:

   Make Federal funds available (low interest loans or grants) 
        to increase EV charging stations across rural America.

   Maintain and expand the EV tax credit for lower income 
        purchasers by making it available at the point of purchase.

   Make investment tax credits available for EV/HEV auto 
        manufacturers and businesses that manufacture EV/HEV parts in 
        rural America.

   Provide grant funds for community colleges, technical 
        schools, union and registered apprenticeship programs, colleges 
        and universities that engage in workforce development programs 
        for EV technicians and electrical workers.

    Finally, public transit is an important way to increase commerce 
and drive down GHG emissions in rural America. Rural Green Partnership 
policies will:

   Invest in high speed rail service to link rural communities 
        with urban job centers and markets.

   Support rural transit services that facilitate access to 
        jobs, schools and services across rural America.
Commercial & Residential
    Approximately 11% of total U.S. GHG emissions come from homes and 
commercial businesses (not including industry). Rural households 
typically face a higher energy burden than their urban and suburban 
counterparts. Low-income rural households are especially hard-hit, with 
an energy burden triple that of higher income families.\5\ Rural 
housing stock is typically older and less energy efficient. On average, 
energy efficiency upgrades can reduce energy burden by up to 25% in 
rural communities.\6\ Rural Green Partnership priorities for this 
sector would:
---------------------------------------------------------------------------
    \5\ Ross, et al., 2018. The High Cost of Energy in Rural America: 
Household Energy Burdens and Opportunities for Energy Efficiency 
(Prepared by ACEE) https://aceee.org/sites/default/files/publications/
researchreports/u1806.pdf.
    \6\ Ibid.

   Expand energy efficiency and renewable energy programs for 
---------------------------------------------------------------------------
        homes and buildings (new programs and retrofits).

   Help rural energy co-operatives expand innovative programs 
        to increase beneficial electrification programs in rural 
        America.

   Increase R&D for supporting more distributed energy systems 
        and integrated energy efficiency measures.

   Incentivize methane emission capture standards from 
        landfills and the efficient recycling and use of food waste.

   Provide loans and grants for energy efficiency at wastewater 
        treatment plants throughout rural America.
Industry
    Industrial processes produce goods and raw materials that are 
essential to our economy yet contribute to roughly 22% of annual GHG 
emissions. Many industrial plants that manufacture chemicals, vehicles 
and equipment, food products, pulp and paper, iron and steel, petroleum 
and biofuels are located throughout rural America and are the economic 
backbone of many of these communities. This is the only economic sector 
expected to significantly increase GHG emissions in the next decade, so 
creative policy solutions will be needed to help rural manufacturers 
cut GHGs while supporting economic growth. The Rural Green Partnership 
will:

   Implement zero and low interest loans for CCUS 
        infrastructure projects that transport carbon dioxide from 
        industrial sources to locations in rural areas where it can be 
        used or permanently stored in geologic sinks.

   Facilitate permitting for CCUS infrastructure and storage 
        reservoir assessments.

   Increase R&D funding and prizes for innovative, scalable 
        uses of carbon dioxide that will lead to new businesses in 
        rural America.

   Offer investment tax credits for industries that use carbon 
        dioxide and reduce emissions.

   Introduce tax incentives to encourage industries to switch 
        from higher CO2 emission fuel sources to zero or low 
        CO2 emission fuel sources.

   Establish tax incentives, loans and grants for the 
        development and use of biobased and sustainable forestry 
        products that lower GHG emissions.

   Provide a federally-backed match to all Small Business 
        Innovation Research (SBIR) recipients that receive funding for 
        the production of sustainably sourced biobased or recycled 
        products.

   Provide tax incentives, grants and technical assistance for 
        rural business that invest in industrial energy efficiency.
Conclusion
    Rural America continues to acutely experience the negative effects 
of climate change. This year alone, farmers across the heartland have 
faced record flooding and weather events that jeopardize both personal 
health and economic livelihoods. At the same time, rural communities 
could contribute significantly to clean energy utilization and more 
sustainable land use practices. The Rural Green Partnership focuses on 
economic growth through mitigation of and adaptability to the effects 
of climate change. Importantly, it gives rural America a front and 
center seat at the climate change table while respecting the unique 
needs and interests of the 19% of the population that call rural 
America home. Significantly lowering future GHG emissions is 
achievable, and rural America is primed to lead the way.
                                 ______
                                 
Submitted Letter by Hon. Kim Schrier, a Representative in Congress from 
                               Washington
    Robert Bonnie,
    Deputy Chief of Staff for Policy and Senior Advisor on Climate,
    United States Department of Agriculture,
    Washington, D.C.

    Dear Mr. Bonnie:

    Congratulations on your recent reappointment to the U.S. Department 
of Agriculture. I am writing to invite you to visit Washington's 8th 
Congressional District for a roundtable meeting with farmers, growers, 
and local stakeholders to discuss climate policy and agriculture with a 
specific focus on ensuring Federal policy supports the productivity of 
lands and the economic resiliency of our rural communities.
    Recent town halls and time spent with farmers and growers in my 
district have shown me they share the urgent need for action on climate 
change. They are the leading stewards of the land and are on the 
frontlines facing the impacts of climate change. Droughts, fires, and 
floods are affecting their livelihoods. Farmers are also driving much 
of the on-the-ground innovation and leading efforts to embrace and 
share climate smart practices. We must recognize, support, and bolster 
contributions from farmers and ensure they have a place at the table in 
Federal policy. That includes open and honest discussion on any 
immediate and downstream impacts Federal policy may have on agriculture 
stakeholders.
    In Washington State, we have a proud farming heritage that goes 
back multiple generations. Washington's climate, rich soils, and large-
scale irrigation make it one of the most productive growing regions in 
the world, enabling farmers to produce over 300 different crops each 
year. We are the nation's top producing state for apples, pears, and 
cherries--many of which are grown in Washington's 8th Congressional 
District. Our growers produce top-quality fruits that are in high 
demand around the globe, with roughly \1/3\ of our crops exported each 
year.
    As the only Member from the Pacific Northwest on the House 
Agriculture Committee, I am honored to be a voice for the farmers and 
growers in the region. I look forward to working together to ensure the 
values and contributions of our agriculture community are recognized 
and ensu[r]ing their voices are heard in ongoing policy discussions on 
climate change and agriculture.
            Sincerely,
            
            
Hon. Kim Schrier,
Member of Congress.
                                 ______
                                 
 Submitted Letters by Hon. Jimmy Panetta, a Representative in Congress 
                            from California
                                Letter 1
September 22, 2020

 
 
 
Hon. Nancy Pelosi,                   Hon. Mitch McConnell,
Speaker,                             Majority Leader,
U.S. House of Representatives,       U.S. Senate,
Washington, D.C.;                    Washington, D.C.;
 
Hon. Kevin McCarthy,                 Hon. Charles Schumer,
Minority Leader,                     Minority Leader,
U.S. House of Representatives,       U.S. Senate,
Washington, D.C.;                    Washington, D.C.
 

    Dear Majority Leader McConnell, Minority Leader Schumer, Speaker 
Pelosi, and Minority Leader McCarthy:

    We, the undersigned organizations and members of the Forest Climate 
Working Group, are writing today to express our strong support for the 
bipartisan REPLANT Act (S. 4357 and H.R. 7843), which would enable the 
U.S. Forest Service to address the millions of acres of National 
Forests in immediate need of reforestation and keep up with future 
demands.
    The Forest Climate Working Group (FCWG) is our country's only 
forest-climate coalition that represents every aspect of U.S. forests 
from government agencies, landowners, forest products, outdoor 
recreation, conservation and wildlife groups, academics, and carbon 
finance experts. Together, we represent diverse and bipartisan 
stakeholders that are committed to advancing scientifically informed 
forest policy that incorporates forests, forest products and natural 
working lands solutions as a key part of climate change mitigation. 
Reforesting National Forests through the REPLANT Act will yield 
significant climate mitigation benefits by sequestering carbon in 
growing trees, while creating jobs in rural communities and protecting 
America's water supplies.
    America's 193 million acres of National Forests are at a 
crossroads. They are a critical part of our daily lives, providing 
clean drinking water, supporting jobs and the economy, naturally 
capturing carbon from the atmosphere, and supporting our outdoor 
heritage. National Forests are the single most important source of 
water in the United States, providing water to 66 million people in 
3,400 communities, including cities.
    Yet, our National Forests are facing new challenges that we need to 
address. These public lands are being rapidly and intensely damaged by 
extreme wildfire, drought, and pests supercharged by a changing 
climate. We must speed up the process of reforesting millions of acres 
of degraded forestland to restore its ability to collect and filter 
drinking water, naturally capture carbon dioxide, generate wood and 
related forest jobs, and provide for wildlife and recreation. In some 
National Forests this is a ``now or never'' chance to reforest burned 
over areas that are not reforesting on their own. Without action, we 
risk losing these forests forever.
    The REPLANT Act will address this crisis by modernizing the 
Reforestation Trust Fund (16 U.S.C.  1606a) which was established by 
Congress in 1980 to reforest our National Forests. The Reforestation 
Trust Fund is funded by reliable, plentiful tariffs on designated wood 
products. There is just one catch: due to an outdated $30 million cap, 
most of these tariff revenues are unavailable for addressing ever-
increasing critical reforestation needs.
    This bipartisan legislation, introduced by Senators Udall, Portman, 
and Stabenow and Representatives Panetta, Simpson, Schrier, and 
LaMalfa, will remove this outdated cap, enabling the Forest Service to 
address almost 8 million of acres of National Forests in need of 
reforestation,\1\ which includes 1.3 million acres of forests in need 
of immediate treatment. This 1.3 million acre priority list is growing 
by approximately 200,000 acres each year because funding has not kept 
up with even the most urgent reforestation needs. Through the REPLANT 
Act, the Forest Service will be able to treat these priority lands and 
plant or naturally regenerate more than 1.2 billion trees over the next 
decade alone, creating nearly 49,000 jobs.
---------------------------------------------------------------------------
    \1\ USFS field staff report 1.378 million acres need reforestation 
as of 2019. Geospatial analyses suggest even greater need for 
reforestation than the data reported by USFS field staff. The USFS 
Rapid Assessment of Vegetation Condition after Wildfire (RAVG) dataset 
suggests that potential acreage could be as much as three times greater 
(https://data.fs.usda.gov/geodata/rastergateway/ravg/index.php). A 
recent estimate by The Nature Conservancy suggests total reforestation 
need on USFS land could reach 7.7 million acres (Fargione, et al., 2018 
and updated analysis in press Cook-Patton, et al., 2020).
---------------------------------------------------------------------------
    Now more than ever, America is turning to our public lands for 
physical, spiritual, economic and environmental renewal. By recently 
passing the Great American Outdoors Act, Congress made significant, 
strategic investments in repairing these lands. The REPLANT Act builds 
on this momentum by ensuring we can reforest millions of acres of 
National Forests and enjoy their benefits for generations. We urge you 
to prioritize and pass this vital legislation.
            Sincerely,

 
 
 
1. American Forest Foundation        20. Open Space Institute
2. American Forests                  21. Pinchot Institute for
                                      Conservation
3. Binational Softwood Lumber        22. Port Blakely Timber
 Council
4. California Forestry Association   23. PotlatchDeltic
5. EFM                               24. Rayonier
6. Forest Landowners Association     25. Society of American Foresters
7. Forest Stewards Guild             26. Sonen Capital
8. Green Diamond Resource Company    27. Spatial Informatics Group--
9. Hancock Natural Resource Group     Natural Assets Laboratory (SIG-
                                      NAL)
10. Land Trust Alliance              28. Sustainable Forestry and Land
                                      Retention Network
11. Michigan State University,       29. Sustainable Forestry Initiative
 Department of Forestry
12. Molpus Woodlands Group           30. The Climate Trust
13. National Alliance of Forest      31. The Forestland Group
 Owners
14. National Association of          32. The Nature Conservancy
 Conservation Districts
15. National Association of Forest   33. The Trust for Public Land
 Service Retirees
16. National Association of State    34. The Westervelt Company
 Foresters
17. National Association of          35. University of Kentucky,
 University Forest Resources          Department of Forestry
 Programs
18. National Wildlife Federation     36. Weyerhaeuser
19. New England Forestry Foundation  37. WoodWorks--Wood Products
                                      Council
 

                                Letter 2
September 30, 2020

 
 
 
Hon. Nancy Pelosi,                   Hon. Kevin McCarthy,
Speaker,                             Minority Leader,
U.S. House of Representatives,       U.S. House of Representatives,
Washington, D.C.;                    Washington, D.C.
 

    Dear Speaker Pelosi and Minority Leader McCarthy:

    We write to express strong support for the REPLANT Act (H.R. 7883), 
a bill that would enable the U.S. Forest Service to address the 
millions of acres of public lands in urgent need of reforestation and 
to keep up with future demands. This bipartisan legislation, introduced 
by Representatives Panetta, Simpson, Schrier and LaMalfa and Senators 
Udall, Portman and Stabenow will lift the cap placed on the 
Reforestation Trust Fund, enabling the Forest Service to replant and 
regenerate 1.2 billion trees every decade across America's National 
Forests. This is projected to create nearly 49,000 forestry-related 
jobs, inject economic vitality into gateway communities, and support 
the broader outdoor recreation economy.
    Prior to the pandemic, the outdoor recreation economy was 
generating $778 billion in gross economic output annually and was 
growing faster than the GDP. The sector provides millions of green, 
sustainable jobs that cannot be outsourced or exported. Many of these 
jobs are located in rural towns that look to the outdoor recreation 
economy as a way to strengthen their communities. For this industry to 
keep growing, the nation must have access to healthy public lands. This 
is truer than ever, due to Americans being eager to experience the 
outdoors as they look for ways to safely manage through the pandemic. 
The REPLANT Act's investment in our industry's core infrastructure--
public lands and waters--will allow our gateway towns to get back to 
what they do best: support Main Street entrepreneurs, put people back 
to work, and allow Americans to benefit from time spent outside.
    The REPLANT Act will also deliver important long-term value. Over 
the long haul, the outdoor recreation sector and our gateway 
communities depend on a healthy climate and healthy places to play in 
order to remain viable. Right now, America's 193 million acres of 
National Forests are being damaged much more rapidly and intensely by 
extreme wildfire, drought, and pests supercharged by a changing 
climate. The REPLANT Act will address this crisis this by modernizing 
the Reforestation Trust Fund and provide it with the needed funds to 
catch up and keep up with growing reforestation needs.
    The Forest Service already has prioritized more than 1.3 million 
acres of land for reforestation to repair disturbances such as severe 
wildfire. This waiting list is growing by approximately 200,000 acres 
each year because funding has not kept up with rising reforestation 
needs. Moreover, given the increasing intensity of wildfires and their 
severe impact on forest soils and landscapes, more and more of these 
impacted forests will be lost forever unless we invest in Reforestation 
Trust Fund resources to bring them back.
    The resulting severe impacts on the outdoor recreation sector would 
frustrate economic and job recovery, unduly limit public recreation use 
of public lands, and hamper future economic growth. In contrast, the 
REPLANT Act will bolster outdoor recreation and economic growth across 
the country; add 1.2 billion trees on 4.1 million acres of our National 
Forests each decade; create thousands of green jobs, primarily in rural 
communities hardest hit by COVID-19; capture millions of metric tons of 
carbon dioxide; and protect drinking water supplies for millions of 
Americans.
    At this challenging moment in our history, America is turning to 
our public lands for physical, spiritual, economic, and environmental 
renewal. The Great American Outdoors Act, which was recently signed 
into law, shows that Congress is ready to make strategic investments in 
repairing our public lands--investments that will put Americans back to 
work and better meet the needs of the public. To continue building on 
this momentum, we need the REPLANT Act. We strongly urge you to advance 
the REPLANT Act to secure the lasting recreation and economic value of 
our National Forests for generations to come.
            Sincerely,

 
 
 
REI Co-op                            Arcteryx
Patagonia                            Keen
Burton                               Hydro Flask
Columbia                             Klean Kanteen
The North Face                       Jones Snowboards
Big Agnes                            NEMO Equipment
Petzl                                L.L Bean
Renee Thompson Designs               Peak Designs
Ruffwear                             Mountain Shades/Optic Nerve
Salewa                               Tahoe Mountain Sports
Western Spirit Cycling               Yakima Products
Rooted, Grounded, Renewed            22 Designs
Alpine Shop, Ltd.                    The Conservation Alliance
Outdoor Industry Association         Outdoor Recreation Roundtable
California Outdoor Recreation        American Sportfishing Association
 Partnership
American Horse Council               Specialty Equipment Market
                                      Association
International Snowmobile             National Association of RV Parks
 Manufacturers Association            and Campgrounds
 

cc: House Agriculture Committee Chairman Collin C. Peterson and Ranking 
Member K. Michael Conaway.
                                Letter 3
November 10, 2020

 
 
 
Hon. Nancy Pelosi,                   Hon. Mitch McConnell,
Speaker,                             Majority Leader,
U.S. House of Representatives,       U.S. Senate,
Washington, D.C.;                    Washington, D.C.;
 
Hon. Kevin McCarthy,                 Hon. Charles Schumer,
Minority Leader,                     Minority Leader,
U.S. House of Representatives,       U.S. Senate,
Washington, D.C.;                    Washington, D.C.
 

    Dear Speaker Pelosi, Minority Leader McCarthy, Majority Leader 
McConnell, and Minority Leader Schumer:

    Our businesses, which collectively employ nearly 70,000 people, 
generate more than $26B in revenue annually, and represent a spectrum 
of industries and perspectives, share a common commitment to climate 
solutions that will foster resilience for our communities, our national 
economy, and our planet. We recognize the particularly vital role that 
forests play as a natural asset that efficiently stores and manages 
carbon. In that context, we are writing to urge action before the end 
of this Congress on the bipartisan REPLANT Act (H.R. 7843/S. 4357), a 
bill that would address the critical reforestation backlog in America's 
National Forests and catalyze 49,000 jobs over the next decade.
    American businesses recognize the existential threat posed by 
climate change and are helping to lead the way to a better future with 
dynamic, market-based changes to reduce our carbon footprint and invest 
in in natural carbon solutions. Actions by the business community, 
while critical, must be complemented by Congressionally-led public 
policy actions. Enhancing America's forest resources is a necessary 
component of that public response. America's forests and forest 
products already capture and store 15 percent of our nation's carbon 
emissions each year, with the potential for substantially increased 
sequestration through targeted reforestation efforts.
    The REPLANT Act will dramatically increase the pace of 
reforestation on America's 193 million acres of National Forests--
providing the resources to regenerate 1.2 billion trees per decade and 
remove almost 758 million metric tons of carbon dioxide equivalent over 
their lifetimes.
    The Forest Service has identified more than 1.3 million acres of 
National Forest awaiting reforestation due to disturbances such as 
severe wildfire. This waiting list is growing by approximately 200,000 
acres each year as funding has not kept up with rising reforestation 
needs. Moreover, as severe wildfires and disease increase across the 
country, more and more forests will be lost forever without 
Reforestation Trust Fund resources to bring them back. The REPLANT Act 
will respond to accelerated forest losses by removing the 40 year old 
cap on the Reforestation Trust Fund providing essential funding, 
billions of trees and create and support approximately 49,000 jobs.
    Beyond its positive climate impacts, the REPLANT Act will provide 
significant additional community benefits as well. Forests provide 
clean drinking water for more than 50 percent of all Americans. They 
clean our air and help reduce respiratory diseases such as asthma. They 
support fish and wildlife habitat, forest recreation opportunities, and 
the broader outdoor economy. The REPLANT Act is a win-win solution that 
addresses the full spectrum of these needs.
    We strongly support the REPLANT Act and urge Congress to pass it 
this year.
            Sincerely,
            
            

 
 
 
[Salesforce.com, inc.]               [Sazerac Company, Inc.]
 

                                     
                                     

 
 
 
[Recreational Equipment, Inc.]       [Independent Stave Company, Inc.]
 

                                     
                                     

 
 
 
[Sierra Nevada Brewing Co.]          [Robinson Stave Mill and East
                                      Bernstadt Cooperage]
 

cc: House Agriculture Committee Chairman Collin C. Peterson and Ranking 
Member K. Michael Conaway; Senate Agriculture Committee Chairman Pat 
Roberts and Ranking Member Debbie Stabenow.

                                Letter 4
November 24, 2020

 
 
 
Hon. Mitch McConnell,                Hon. Charles Schumer,
Majority Leader,                     Minority Leader,
U.S. Senate,                         U.S. Senate,
Washington, D.C.;                    Washington, D.C.;
 
Hon. Nancy Pelosi,                   Hon. Kevin McCarthy,
Speaker,                             Minority Leader,
U.S. House of Representatives,       U.S. House of Representatives,
Washington, D.C.;                    Washington, D.C.
 

    Dear Majority Leader McConnell, Speaker Pelosi, Democratic Leader 
Schumer, and Republican Leader McCarthy:

    On behalf of the undersigned organizations, which together 
represent millions of hunters and anglers all across America, we would 
like to express our thanks for your important conservation achievements 
thus far in the 116th Congress, and to urge action before adjournment 
to pass the REPLANT Act (S. 4357 and H.R. 7843). This bipartisan 
legislation provides a critically needed response to the damage that 
wildfires and other disasters continue to inflict on our National 
Forests, the vital fish and wildlife habitats these lands host, and the 
local recreation economies they support.
    Public lands, and specifically our nation's network of National 
Forests, are home to a truly remarkable array of game and nongame 
wildlife populations, and they provide irreplaceable hunting, fishing, 
and other public recreation access. These resources, however, have 
suffered from devastating forest losses from the increasing number and 
severity of wildfires and from the destructive impacts of severe 
storms, drought, disease, and insect infestation. Inadequate funding to 
address these losses has resulted in a backlog of unmet reforestation 
need in the National Forests; the U.S. Forest Service has identified 
more than 1.3 million acres that may never recover without replanting 
or regeneration assistance, and other estimates of the need are far 
higher, even as the backlog grows by some 200,000 acres annually. Lands 
at risk include forest and riparian habitats essential for key fish and 
wildlife populations, and just as essential for the future of outdoor 
recreation in a host of public land-dependent communities.
    The REPLANT Act will reverse these unsustainable losses by removing 
the outdated funding cap on the Reforestation Trust Fund, which has 
remained fixed at just $30 million per year for the past 4 decades, 
despite exponentially growing needs throughout the National Forest 
System. Enactment will bring the resources to maintain the outdoor 
recreation value of these vital public lands and to eliminate the 
reforestation backlog in National Forests within 10 years. At the same 
time, it will create and support an estimated 49,000 reforestation 
jobs, establish an additional 1.2 billion trees per decade, and 
sequester an estimated 75 million metric tons of carbon per decade, 
with corresponding benefits to wildlife communities everywhere.
    The REPLANT Act is a win-win opportunity to enhance stewardship and 
resource management of our National Forests, and to ensure their 
ongoing resource values for local communities and for America's 
sportsmen and women. With deep appreciation for your commitment to our 
nation's fish and wildlife, our public lands, and our outdoor economy, 
we strongly support this important legislation and ask that you do all 
you can to secure passage without delay.
            Sincerely,

 
 
 
American Woodcock Society            National Wild Turkey Federation
Archery Trade Association            National Wildlife Federation
Boone & Crockett Club                North American Grouse Partnership
California Waterfowl                 Orion: The Hunter's Institute
Campfire Club of America             Pheasants Forever
Congressional Sportsmen's            Pope and Young Club
 Foundation
Conservation Force                   Public Lands Foundation
Council to Advance Hunting and the   Quail Forever
 Shooting Sports
Dallas Safari Club                   Ruffed Grouse Society
Delta Waterfowl                      Texas Wildlife Association
Houston Safari Club                  Theodore Roosevelt Conservation
                                      Partnership
Izaak Walton League of America       Whitetails Unlimited
Masters of Foxhounds Association     Wild Sheep Foundation
Mule Deer Foundation National        Wildlife Forever
 Association of Forest Service       Wildlife Management Institute
 Retirees
National Deer Association            Wildlife Mississippi
National Shooting Sports Foundation
 

                                 ______
                                 
                          Submitted Questions
Response from Jim Cantore, Senior Meteorologist, The Weather Channel, 
        Atlanta, GA
Questions Submitted by Hon. Jimmy Panetta, a Representative in Congress 
        from California
Forests and Climate Change
    Question 1. Mr. Cantore, I appreciate your efforts to connect the 
dots between climate change and billion-dollar natural disasters like 
the record-breaking wildfires that my district experienced just a few 
months ago.
    While wildfires are natural and beneficial in certain contexts, the 
fires we have been experiencing across the American West are laying 
claim to the very forestland we rely on to sequester 10% of our 
nation's emissions.
    In California alone, we lost an unprecedented 4.4 million acres to 
wildfires last year, about 4% of our entire state, with over 640,000 of 
those acres in my district.
    Reforestation efforts, like those supported by my REPLANT Act, 
which increases funding for the Reforestation Trust Fund, can help us 
reclaim the incomparable value of forests as carbon sinks while also 
helping protect our communities from mudslides and other disastrous 
after-effects.
    In addition to ecologically-sound post-fire reforestation, we must 
also do a better job of protecting existing forests, particularly old-
growth forests, from future fire risk.
    Mr. Cantore, from your perspective as a meteorologist, can you 
elaborate on the climate-related benefits of better protecting existing 
forests and increasing the pace and quantity of reforestation efforts? 
What happens if don't take these steps?
    Answer. Healthy forests are good for the natural environment and 
ecosystem. In addition to carbon storage, forests serve as wildlife 
habitats, supply fiber and wood products and are enjoyed for the 
recreational activities they provide. As you mention, we rely on our 
forests to sequester roughly 10% of the country's emissions. It is 
important we do not minimize or lose this important role forests play 
because the more CO2 in the atmosphere the more warming and 
subsequent negative impacts. Extreme heat and drought, which is 
increasing across portions of the country, especially the western U.S., 
including California, can cause stress and reduce forest productivity 
and even increase tree mortality. It is important to preserve and 
restore our nation's forests, because without good maintenance and 
preventive measures we could continue to see the erosion of quality and 
quantity of our great forests, allowing the negative effects such as 
large wildfires, mudslides and loss of habitat to continue. REPLANT Act 
also adds native species back to their natural environment faster. What 
I can't tell you is when we can string several average or above average 
water/snow years together here (also needed for a healthy forest).

    Question 2. Mr. Cantore, when we talk about reforestation, we also 
need to talk about climate-forward forestry, which means planting the 
right tree in the right place. Do you have any thoughts to share on how 
we can be smarter about planting trees, including climate-ready species 
that are better suited to climate changes?
    Answer. Planting native species has always been a great practice. 
We have seen what adding non-native trees and plants can do in the 
wrong areas: like aiding the 2007 Harris fire in San Diego and covering 
the southeast in invasive kudzu that was brought in for erosion 
control. That said, my knowledge of certain species of trees and their 
ability to flourish in certain regions of the country is limited as a 
meteorologist. I will say, however, climate projections should be 
considered when choosing where and when to plant certain tree species. 
Some areas of the country may become more prone to drought, for 
example, so trees that are better at thriving through times of low 
water would be a smarter choice.
Forestry Workforce
    Question 3. Mr. Cantore, research has shown that each $1 million 
invested in forest restoration and reforestation has the potential to 
support as many as 40 jobs.
    As Congress looks ahead to an infrastructure package, I firmly 
believe we must invest Federal resources in workforce development in 
forestry sector.
    That's why I introduced the Save Our Forests Act, which would 
provide funding to address chronic staffing shortages at the U.S. 
Forest Service. Increasing staff capacity in our Federal forests will 
not only help prevent fires but it will also help create the capacity 
needed to implement climate solutions in our Federal forests and the 
wildland-urban interface.
    Mr. Cantore, based on your experience covering and studying natural 
disasters and their aftermath, do you think bolstering the forestry 
workforce will help create and sustain more resilient forests that are 
better able to sequester carbon?
    Answer. Unfortunately, I don't know enough about the forestry 
workforce and their role in creating resilient forests to answer 
directly. I can, however, speak broadly on the topic of natural 
disasters. It has been my experience that the more resources, funding, 
and attention focused toward prevention and education can help mitigate 
losses after a natural disaster and potentially lead to a quicker 
return to normal. We have seen examples of communities building 
intelligently around floodplains to minimize infrastructure loss during 
heavy rain events. And better building codes have shown to make an 
incredible difference in reducing damage after severe weather and 
hurricanes. Marshland and forests can be natural barriers to many 
things and any attempt to shrink these beneficial ecosystems is further 
harm to our planet, in my opinion.
Response from Pamela N. Knox, Director, University of Georgia Weather 
        Network; Agricultural Climatologist, UGA Cooperative Extension, 
        Athens, GA
Questions Submitted by Hon. Chellie Pingree, a Representative in 
        Congress from Maine
    Question 1. One thing my bill, the Agriculture Resilience Act, 
focuses on is additional technical assistance and training on climate 
resilience and reducing emissions-not just for farmers, but also for 
the NRCS professionals and extension agents who work with them. Given 
your previous work with the Southeast Climate Hub, how would that 
additional support improve adoption of some of the climate-smart 
practices we discussed at the hearing?
    Answer. Thank you for tackling this important question. The 
additional support provided by your bill would improve adoption of 
climate-smart practices in several ways. First, by sponsoring targeted 
research on methods for applying smart irrigation and other climate-
smart management practices, the bill will help scientists to provide 
specific, actionable methods for reducing the use of water and 
agricultural chemicals that farmers can take and utilize on their 
farms. This will benefit the farmers economically as well as reduce 
emissions of greenhouse gases. It will also improve the health of 
surrounding ecosystems and communities by improvements in air and water 
quality. Second, the support would foster the use of workshops, 
publications, and field visits to allow direct transmission of the 
applied research to those who work with producers ``on the ground'', 
including extension agents and NRCS professionals. Providing ``hands-
on'' experience is a more targeted and useful approach to providing 
technical assistance than just publications, although those also have 
their place in providing information to farmers. Third, in that process 
of interaction, farmers would also be able to guide future development 
of useful methods of farm management that would be driven by the most 
important needs of the farm communities. As people who are actually 
doing the daily work of farming, they are best equipped to know what 
management strategies are workable and economically valuable as well as 
sustainable. That will ensure the best use of the funds and other 
resources provided by the Agriculture Resilience Act to directly 
benefit both agricultural producers and the larger community through 
improvements in climate resilience.

    Question 2. One of the issues you mentioned in your testimony is a 
great interest of mine--reducing greenhouse gas emissions by reducing 
food waste. Can you elaborate on how food waste contributes to climate 
change and where you see opportunities to reduce food waste throughout 
the supply chain?
    Answer. As you have pointed out, food waste contributes 
significantly to greenhouse gas emissions. This occurs in a variety of 
ways. When food is produced and then thrown away unused, all of the 
water, chemicals, fuel, and soil nutrients that went into the 
production of that food are essentially discarded too, resulting in 
unnecessary emissions of greenhouse gases, loss of available water, and 
reduced productivity of the soil. That will have to be supplemented in 
future crops on those fields, resulting in additional inputs of fuel, 
water, and chemicals that will also contribute to greenhouse gas 
emissions. Transportation of that food costs time and fuel to bring the 
food from the field to the factories or markets where they are 
processed or purchased for consumption. That transportation also adds 
to the emission of greenhouse gases through the use of fuel to power 
the trucks and trains needed for moving the products through the 
system. When food waste is discarded, either at the factory level or in 
individual kitchens, it is often placed into landfills where it decays 
anaerobically into methane, one of the most powerful greenhouse gases 
in its ability to add to global warming. Landfills are the third 
largest human-related source of methane emissions in the United States, 
and so reductions in landfill emissions by eliminating or decreasing 
food waste would contribute significantly to reductions in greenhouse 
gas emissions overall.
    Fortunately, there are a number of methods available to use the 
food waste before it decays. This includes the use of digesters which 
convert the methane into usable fuel, feeding of food waste to 
livestock, and composting on municipal and individual scales, which 
reduce the output of methane. Encouraging factories to adopt lower-
waste methods for processing the food and consumers to make better use 
of their food so that less is thrown out are also opportunities for 
reducing the impact of food waste on climate change.

    Question 3. In your testimony, you made the point that farmers who 
own their land have the greatest incentive to improve their soil 
health. However, a huge number of producers, particularly young people 
and farmers of color, don't own the land they farm. In your view, how 
can we improve land access for these farmers? How can our policies 
better incentivize renters to make long-term investments in soil health 
if they're not sure they'll be the ones who reap the rewards?
    Answer. To encourage the improvement of agricultural soils, we need 
to take a two-pronged approach. First, we need to encourage landowners 
to participate in efforts to increase carbon sequestration on their 
land by providing monetary or other incentives to encourage their 
tenants to practice carbon-smart techniques for improving their soils 
through the use of no-till agriculture, cover crops, and other 
regenerative practices. Landowners should be given the means of 
communicating how to do this to their tenants and rewarding those 
tenants who are best able to practice this, for example, by bonuses for 
excellent land use, lower rents, or multi-year leases that encourage 
smarter use of the land over numerous years.
    Second, tenant farmers should be given access to information about 
climate-smart practices such as smart irrigation to reduce unneeded 
water use and fuel for pumping. They should also be provided with 
information from extension agents, NRCS specialists, and others on how 
to use inputs like chemicals efficiently to reduce overuse and to 
minimize their inputs, which will increase the amount of money they 
make on each crop. Access to broadband internet services is an 
important part of making the best use of their land, but it also 
requires knowledge acquired through training and education to see how 
these sustainable techniques work in practice. Access to affordable 
soil moisture sensors and other weather information will allow them 
make the best use of the information they have. Programs to encourage 
producers to purchase their own land such as low-cost loans should also 
be considered.
Question Submitted by Hon. Salud O. Carbajal, a Representative in 
        Congress from California
    Question. All our public forests are an incredible carbon sink, 
especially our intact temperate rainforests along the West Coast and in 
Alaska. While some carbon is stored in long lived wood products, far 
more is lost to the atmosphere as the result of logging and soil 
disturbance. I believe that legislation such as the Roadless Area 
Conservation Act, and other protective policies and legislation are 
necessary in our climate fight. According to the best available 
science, what are some key policy opportunities to elevate the role our 
forests play storing and sequestering carbon?
    Answer. The Roadless Area Conservation Act and other legislation 
are important steps towards protecting and maintaining our immense and 
valuable forests across the United States, especially those in the 
western U.S. that are less touched by human activities than those in 
the eastern U.S. This protection is important not only because of the 
incredible amounts of carbon that they store, but also to maintain 
valuable ecosystem diversity and water quality of streams flowing 
through the forests. We can elevate the role of forests in sequestering 
carbon by first recognizing that the best way to reduce emission of 
greenhouse gases is not to emit it in the first place. That means 
reduction in the widespread clearcutting of forests in favor of more 
targeted harvesting of trees that reduces soil disturbance and 
preserves ecological diversity and water quality. Preservation of older 
and more diverse forests is an important part of that solution. It also 
means a reduction in the uses of forest products like paper so that 
fewer trees are needed, including a shift to other sustainable products 
like bamboo or hemp. Policies should also encourage improved management 
of forest lands to decrease the threat of wildfires, which release huge 
amounts of carbon into the atmosphere along with pollutants like soot 
when they occur. That would also reduce the health and property risks 
to vulnerable populations living near those forests.
    Once trees are harvested, they should be quickly replaced by other 
trees to help absorb the carbon released by the trees that were 
removed. Restoration and replacement of degraded forests will also 
improve their ability to absorb excess carbon; in fact, some studies 
suggest that those processes could provide almost a third of the 
mitigation needed to counteract climate change by 2030. Extending our 
knowledge of wise management of forests to other countries would also 
help with greenhouse gas emissions overall, since wood use for fuel and 
clearing of tropical rain forests for food production are large 
contributors to greenhouse gas emissions around the world.
Questions Submitted by Hon. Jimmy Panetta, a Representative in Congress 
        from California
Land Ownership and Climate
    Question 1. Ms. Knox, you mentioned that producers who own their 
land, rather than rent it, reap greater benefits from taking steps to 
improve the health of their soils.
    I completely agree--when farmers, ranchers, and foresters own their 
land, they not only have a greater incentive but also a greater 
capacity to invest in its long-term health.
    In my district on the Central Coast, organizations like the 
Agriculture and Land-Based Training Association (ALBA) are working to 
help limited-resource minority farmers launch organic farming 
businesses.
    Graduates of ALBA's training program now own and operate some of 
the most successful and ecologically conscious operations in my 
district.
    Ms. Knox, Can you elaborate on the connection between land 
ownership and climate-smart agriculture?
    Answer. As you point out, farmers, ranchers, and foresters that own 
their land have a greater incentive to protect it as well as invest in 
its long-term health. When you rent the land and don't own it, the 
increased value due to higher organic matter in soils, reduced erosion 
and loss of valuable topsoil, and water-holding capacity benefits the 
landowner much more than the farmer working the land, since the 
landowner can raise the rent in future years to capture the increased 
value of better soil fertility and structure. Little to none of the 
economic benefit is returned to the farmer who improved the soil in the 
first place. In some cases, the original farmer may be priced out of 
renting that land in future years, so any extra work he or she puts 
into improving the land can negatively affect their ability to rent 
those fields next year. If you own the land, then any benefits you get 
from practicing climate-smart management are returned directly to you 
in reduced need to add water and fertilizer in subsequent years, which 
increases the profitability of the harvests in later years. Many 
climate-smart techniques such as no-till production and smart 
irrigation also promote wiser and more judicious use of inputs like 
pumped irrigation water and agricultural chemicals like fertilizers, 
fungicides, and herbicides, which cost money both in direct purchases 
as well as in labor costs to apply them. This results in higher net 
income to the farmers since less money is paid out to protect the crops 
and supplement soil nutrient levels. Organic farming reduces the cost 
of man-made chemicals and also provides an economically valuable 
product that improves farmers' net profit as well as improves 
ecological diversity and soil fertility.

    Question 2. Ms. Knox, Do you think USDA can better achieve its 
climate goals by creating more economic opportunities for minority 
farmers?
    Answer. The USDA must achieve its climate goals by engaging with 
farmers at all scales to promote climate-smart approaches to farming. 
Engaging with minority farmers is an important part of that approach 
since many minority farmers have a strong interest in preserving their 
family farms for future generations. That requires excellent care of 
the farm characteristics such as soil fertility, water-holding 
capacity, and reductions in erosion to ensure the future productivity 
of their land. All of these approaches have the double benefit of both 
reducing emissions of greenhouse gases and improving the economic well-
being of the minority farmers as well as their farmland. Additional 
methods such as the work promoted by organizations like the Agriculture 
and Land-Based Training Association (ALBA) to educate and encourage the 
development of organic farming businesses have the added advantage of 
providing minority farmers with highly profitable organic produce that 
maximizes their net income from selling their products.
Question Submitted by Hon. Glenn Thompson, a Representative in Congress 
        from Pennsylvania
    Question. In my district, we have a great example of an effort to 
tap private markets and private capital to capture and store carbon in 
our forests--which is also bringing new private money to rural, small 
family forest owners, helping them afford to stay on the land and 
manage it well.
    Ms. Knox, what role do you see these private markets playing and 
how can we best leverage these opportunities to bring private sector 
support to rural America?
    Answer. Private markets play an integral role as partners with 
agriculture and forestry in providing information, tools, and capital 
to producers working at all scales, from the largest commercial growers 
to the smallest family farms. They have the ability to react more 
quickly than many government agencies to disasters and changing market 
conditions that can affect the value of working forests. Private 
markets can help family forest owners by providing education and 
guidance on proper maintenance of their forest lots to maximize the 
value of the trees on those lots and determine appropriate timing for 
sales of the timber to maximize their profit overall. They can also 
help farmers replace harvested trees with new seedlings that will 
continue to absorb carbon from the atmosphere and provide future profit 
for those families. Private markets can also promote the wise use of 
forest products for low-carbon building materials in both residential 
and commercial buildings and the use of wood pellets for fuel. By 
putting private markets to use, we can provide a much wider array of 
targeted services to family forest owners than government agencies 
could do without their expertise.
Response from Zippy Duvall, President, American Farm Bureau Federation, 
        Washington, D.C.
Question Submitted by Hon. Jimmy Panetta, a Representative in Congress 
        from California
Role of Specialty Crops in USDA Climate Efforts
    Question. I represent the Central Coast of California, also known 
as the Salad Bowl of the World. The farmers and farmworkers in my 
district grow over 100 specialty crops--you name it, we grow it--and 
they are part of a very rich agricultural history in the region.
    Mr. Duvall, while you didn't specifically mention specialty crop 
producers in your testimony, I know that many of your members are 
specialty crop producers, and I am proud to represent many of those 
members on the Central Coast.
    Have you engaged with your members in the specialty crop sector to 
ensure their views are being considered as Congress and USDA work to 
develop strategies to incentivize more climate-smart agriculture?
    Answer. The American Farm Bureau Federation represents growers of 
every facet of agriculture, including specialty crops, as you noted. I 
agree that it is important their viewpoints are part of this 
conversation surrounding climate too and I can assure you they've had a 
voice both within our organization and beyond. Much of our climate work 
has been in conjunction with the Food and Agriculture Climate Alliance 
in which several organizations specifically representing specialty crop 
producers are members.
    We believe Congress and USDA must take into consideration the 
diversity of American agriculture when crafting any climate policy. 
Existing carbon markets may not provide the same level of opportunity 
to all farmers, growers, ranchers, and foresters due to regional 
differences, crop and production types, total acreage under crop 
production, and farm size. Efforts should focus on reducing these 
barriers and providing a range of opportunities to ensure broad 
participation in climate-smart agricultural practices.
Question Submitted by Hon. Glenn Thompson, a Representative in Congress 
        from Pennsylvania
    Question. In my district, we have a great example of an effort to 
tap private markets and private capital to capture and store carbon in 
our forests--which is also bringing new private money to rural, small 
family forest owners, helping them afford to stay on the land and 
manage it well.
    Mr. Duvall--what role do you see these private markets playing and 
how can we best leverage these opportunities to bring private-sector 
support to rural America?
    Answer. Our mission at Farm Bureau is to build a sustainable future 
of safe and abundant food, fiber and renewable fuel for our nation and 
the world while ensuring the economic success of farmers, ranchers and 
rural communities. We are excited about opportunities like the one you 
mentioned. Investment in rural communities and keeping our families on 
the land is a priority for us. That is why Farm Bureau is at the table 
working with private industry and Congress to ensure that all 
opportunities are being presented to our landowners. We are exploring 
the best ways to leverage private markets but still must address any 
barriers to farmer participation. With this investment and voluntary, 
incentive-based initiatives, I am excited about the future.
Questions Submitted by Hon. Troy Balderson, a Representative in 
        Congress from Ohio
    Question 1. Thank you for being here, Mr. Duvall. The work and the 
relationship the American Farm Bureau--as well as the Ohio Farm Bureau 
back home--have with Ohio farmers is critical, so thank you for your 
work.
    In data provided by the EPA and USDA, the American Farm Bureau 
calculates that U.S. greenhouse gas emissions from beef, swine, and 
dairy per unit have declined by 8, 18, and 25 percent, respectively, 
between 1990 and 2018.
    Based upon some of the testimony we've heard here today, how do 
these figures fit into the broader narrative of U.S. agriculture being 
the primary culprit of climate change?
    Answer. We certainly do not believe that U.S. agriculture is a 
culprit of climate change, but quite the opposite. We believe U.S. 
agriculture can be part of the solution. U.S. agriculture is just 10% 
of our overall greenhouse gas emissions. And our per unit GHGs have 
fallen, while production has increased. Nearly 100 million more acres 
would have been needed in 1990 to match 2018 production. In the last 30 
years, we lost almost 30 million acres of cropland but on the remaining 
cropland our emissions flux has remained steady while we are producing 
50 percent more per acre. We want to build upon this strong foundation 
of innovation and climate-smart practices and are looking for partners 
to continue to improve.

    Question 2. The EPA attributes 15 percent of global greenhouse gas 
emissions to the United States, with China at 30 percent. Based upon 
the Netflix video ``Kiss the Ground'', in which Mr. Brown appears, I 
get the impression that the way American farmers use their land is 
doing more harm than good.
    Mr. Duvall, how has the AFBF worked with farmers to increase their 
use of environment-benefiting technology on their land and how 
successful would you say these efforts have been?
    Answer. U.S. agriculture has a great sustainability story to tell, 
thanks to the ways we have embraced technology and innovation and 
adopted modern conservation practices. Farmers everywhere want to 
protect our natural resources and keep our land productive for 
generations to come, and we are always looking for ways to do better. 
Unfortunately, American farmers haven't always gotten credit for our 
efforts, and that's partly on us because we haven't been great at 
telling that story. Historically, we weren't engaged in the 
conversation--especially when it comes to climate change--and yet we 
expected the public to somehow know what we were doing and the 
advancements we've achieved.
    Here are a few of the great strides U.S. farmers and ranchers have 
made reducing our environmental footprint and protecting our natural 
resources:

   U.S. agriculture is just 10% of our overall greenhouse gas 
        emissions.

   Ag's per unit GHGs have fallen, while production has 
        increased. Nearly 100 million more acres would have been needed 
        in 1990 to match 2018 production.

   140 million acres (15% of all farmland) are enrolled in USDA 
        conservation programs. That's equal to the total land area of 
        California and New York combined.

   In 2018 alone, the use of ethanol and biodiesel reduced GHG 
        emissions by 71 million metric tons. That's the equivalent of 
        taking 17 million cars off the road.

   In a 5 year period, U.S. farmers and ranchers have put in 
        132% more renewable energy sources including geothermal, solar 
        panels, windmills, hydro systems and methane digesters.

    At the American Farm Bureau Federation, we want U.S. farmers and 
ranchers to be recognized as the leaders they are when it comes to 
climate-smart solutions. That's what led us to join with other U.S. ag 
groups, as well as food, forestry and environmental groups in founding 
the Food and Agriculture Climate Alliance (FACA).
Response from Gabe Brown, Co-Owner/Operator, Brown's Ranch, Bismarck, 
        ND
Question Submitted by Hon. Chellie Pingree, a Representative in 
        Congress from Maine
    Question. I appreciated your reference to the PRIME Act at the 
hearing. I've been working on improving meat and poultry processing 
infrastructure for many years. I view this as a part of the climate 
conversation not just because producers often have to drive their 
animals hundreds of miles to reach the nearest facility, but also 
because it's a part of our food system where greater resilience is 
sorely needed. Can you talk a little about how having a local 
processing option fits into your regenerative operation? What more can 
Congress do to increase processing options?
    Answer. In order to sell our pastured proteins, they must be 
inspected for retail sale. Processors that have their facilities 
inspected are few and far between. We knew that in order to sell our 
products, we needed to invest in a slaughter plant and then patronize 
that plant. In 2014 a group of us started a co-op called Bowdon Meat 
Processors. It is a cooperative that is open for anyone to have animas 
processed there. Congress can allow meat that is processed at state-
inspected facilities the ability to be sold anywhere in the U.S. This 
would allow producers to patronize their local processors but yet they 
would have access to more markets. This would also help to provide food 
security in cases where large processors are closed, such as that which 
occurred during the [COVID]-19 pandemic.
Question Submitted by Hon. Glenn Thompson, a Representative in Congress 
        from Pennsylvania
    Question. In my district, we have a great example of an effort to 
tap private markets and private capital to capture and store carbon in 
our forests--which is also bringing new private money to rural, small 
family forest owners, helping them afford to stay on the land and 
manage it well.
    Mr. Brown--what role do you see these private markets playing and 
how can we best leverage these opportunities to bring private sector 
support to rural America?
    Answer. Government needs to realize that the current farm program 
is not working. Farmers and ranchers assume all of the risk for very 
marginal returns. We need more capital investment in agriculture. There 
are a number of private markets that are looking to purchase carbon to 
offer to industry/businesses for carbon offsets. Congress needs to 
allow and encourage the expansion of these markets. Farmers and 
ranchers need to be paid for the ecological services they provide. I am 
working with a fund that is investing money in farms and ranches that 
are using regenerative practices which will significantly enhance both 
farm profitability and ecosystem function. Congress needs to encourage 
and support regenerative practices.
Response from Michael Shellenberger, Founder and President, 
        Environmental Progress, Berkeley, CA
Question Submitted by Hon. Glenn Thompson, a Representative in Congress 
        from Pennsylvania
    Question. In my district, we have a great example of an effort to 
tap private markets and private capital to capture and store carbon in 
our forests--which is also bringing new private money to rural, small 
family forest owners, helping them afford to stay on the land and 
manage it well.
    Mr. Shellenberger--what role do you see these private markets 
playing and how can we best leverage these opportunities to bring 
private-sector support to rural America?
    Answer. The most important role for the private-sector in farming 
is to increase yields on existing farmland. Doing so lowers the amount 
of land used for farmland, which allows ecosystems and forests that 
store carbon to return. U.S. farmers have been wildly successful at 
increasing yields, and we have some of the most innovative farmers in 
the world. Since the advent of tractors and combine harvesters, the 
amount of U.S. farmland has decreased by 25 percent, an area the size 
of California.
    We should be wary of plans to grow small plots of forest on 
farmland when those forests are not contiguous. While small plots store 
some carbon, they can't be used as habitat by animals who require 
contiguous habitat. Free range meat production should also be avoided. 
Free range or pasture beef requires 14-19 times more land than 
industrial beef and releases 300 to 400 times more carbon emissions. 
Indoor chicken production also has land use and carbon benefits when 
compared to free range chicken.
    The U.S. Federal Government, state governments, and private 
companies should continue to invest in research and development in 
innovative agricultural technologies that boost yields. Governments 
should also support the use of innovative technologies like GMOs, and 
private companies shouldn't prohibit those products in their stores out 
of wrongful environmental concerns.
    For example, one technology that has struggled due to private 
business bans is AquAdvantage salmon, which are genetically modified 
salmon that are grown on land. Because they are grown on land, they 
pose a business opportunity to landowners in rural areas. These farmed 
fish grow twice as fast as wild salmon and require less feed. They are 
incredibly efficient at turning feed into consumer meat. While 8 pounds 
of feed is needed to harvest 1 pound of beef, only 1 pound of feed is 
needed to create 1 pound of AquAdvantage salmon. Fish farming takes 
pressure off of wild salmon, which, like many aquatic species, are 
facing immense pressure from overfishing. Despite these benefits, 
environmental groups oppose AquAdvantage salmon, which they believe 
will eventually enter the wild and displace wild salmon. It is unlikely 
AquAdvantage salmon will ever harm wild salmon since these farmed fish 
are not as fit as wild salmon and would struggle in the wild. These 
environmental groups have persuaded private companies such as Trader 
Joe's, Whole Foods, Costco, Target, and Kroger to not sell AquAdvantage 
salmon.
Question Submitted by Hon. Troy Balderson, a Representative in Congress 
        from Ohio
    Question. The IPCC (Attachment 1) released an assessment in 2018 
which outlined their concerns if global temperatures increased by more 
than 1.5 C from pre-industrial levels. The report also concluded that 
major cuts across our global carbon output would need to be achieved in 
order to prevent this threshold from being crossed. The Institute for 
Energy Research released a report (Attachment 2) last month saying 
global emissions fell by seven percent in 2020.
    Last year, National Geographic published an article (Attachment 3) 
that stated global emissions would need to decline by 7.6 percent each 
year through 2030 and beyond to prevent the IPCC's 1.5 C level from 
being reached.
    Mr. Shellenberger--given these conclusions, what's the most 
productive way for farmers in other countries to play their part? It 
sure feels like we're placing the majority of the burden of agriculture 
emissions on the American farmer, when all I've seen from folks back 
home is an increasing level of environmentally-conscience farming.
    Answer. U.S. farmers deserve recognition for their efforts to boost 
yields and protect the environment. However, we should be wary of any 
farming practices that brand themselves as environmentally friendly but 
require more land or don't maximize yields. Minimizing the land needed 
for farming by maximizing yields is one of the most important 
environmental practices farmers can do.
    Farming only produces ten percent of U.S. carbon emissions, so 
blaming farmers for climate change is not based in fact. But, there are 
ways to decarbonize farming without sacrificing yields. We can use 
clean energy, namely nuclear, to create fertilizer. Tractors and other 
machinery can be powered by electricity or hydrogen that comes from 
clean energy.
    Likewise, farmers in other countries can best help the environment 
by boosting crop yields so that they can use less land for farming and 
allow forests and ecosystems to return. In some countries, yields can 
grow five-fold by modernizing. The U.S. should actively help countries 
boost their crop yields through existing foreign aid programs.
                              attachment 1
[https://www.ipcc.ch/site/assets/uploads/sites/2/2019/05/
SR15_SPM_version_re
port_LR.pdf]
Global Warming of 1.5 C
An IPCC Special Report on the impacts of global warming of 1.5 C above 
        pre-industrial levels and related global greenhouse gas 
        emission pathways, in the context of strengthening the global 
        response to the threat of climate change, sustainable 
        development, and efforts to eradicate poverty
Summary for Policymakers *
---------------------------------------------------------------------------
    * Editor's note: the full report is retained in Committee file and 
is available at: https://www.ipcc.ch/sr15/download/#full.
---------------------------------------------------------------------------
          Drafting Authors:

          Myles Allen (UK), Mustafa Babiker (Sudan), Yang Chen (China), 
        Heleen de Coninck (Netherlands/EU), Sarah Connors (UK), Renee 
        van Diemen (Netherlands), Opha Pauline Dube (Botswana), Kristie 
        L. Ebi (USA), Francois Engelbrecht (South Africa), Marion 
        Ferrat (UK/France), James Ford (UK/Canada), Piers Forster (UK), 
        Sabine Fuss (Germany), Tania Guillen Bolanos (Germany/
        Nicaragua), Jordan Harold (UK), Ove Hoegh-Guldberg (Australia), 
        Jean-Charles Hourcade (France), Daniel Huppmann (Austria), 
        Daniela Jacob (Germany), Kejun Jiang (China), Tom Gabriel 
        Johansen (Norway), Mikiko Kainuma (Japan), Kiane de Kleijne 
        (Netherlands/EU), Elmar Kriegler (Germany), Debora Ley 
        (Guatemala/Mexico), Diana Liverman (USA), Natalie Mahowald 
        (USA), Valerie Masson-Delmotte (France), J. B. Robin Matthews 
        (UK), Richard Millar (UK), Katja Mintenbeck (Germany), Angela 
        Morelli (Norway/Italy), Wilfran Moufouma-Okia (France/Congo), 
        Luis Mundaca (Sweden/Chile), Maike Nicolai (Germany), 
        Chukwumerije Okereke (UK/Nigeria), Minal Pathak (India), Antony 
        Payne (UK), Roz Pidcock (UK), Anna Pirani (Italy), Elvira 
        Poloczanska (UK/Australia), Hans-Otto Portner (Germany), Aromar 
        Revi (India), Keywan Riahi (Austria), Debra C. Roberts (South 
        Africa), Joeri Rogelj (Austria/Belgium), Joyashree Roy (India), 
        Sonia I. Seneviratne (Switzerland), Priyadarshi R. Shukla 
        (India), James Skea (UK), Raphael Slade (UK), Drew Shindell 
        (USA), Chandni Singh (India), William Solecki (USA), Linda Steg 
        (Netherlands), Michael Taylor (Jamaica), Petra Tschakert 
        (Australia/Austria), Henri Waisman (France), Rachel Warren 
        (UK), Panmao Zhai (China), Kirsten Zickfeld (Canada).

          This Summary for Policymakers should be cited as:

          IPCC, 2018: Summary for Policymakers. In: Global Warming of 
        1.5 C. An IPCC Special Report on the impacts of global warming 
        of 1.5 C above pre-industrial levels and related global 
        greenhouse gas emission pathways, in the context of 
        strengthening the global response to the threat of climate 
        change, sustainable development, and efforts to eradicate 
        poverty [Masson-Delmotte, V., P. Zhai, H.-O. Portner, D. 
        Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. 
        Pean, R. Pidcock, S. Connors, J.B.R. Matthews, Y. Chen, X. 
        Zhou, M.I. Gomis, E. Lonnoy, T. Maycock, M. Tignor, and T. 
        Waterfield (eds.)]. In Press.
Introduction
    This Report responds to the invitation for IPCC `. . . to provide a 
Special Report in 2018 on the impacts of global warming of 1.5 C above 
pre-industrial levels and related global greenhouse gas emission 
pathways' contained in the Decision of the 21st Conference of Parties 
of the United Nations Framework Convention on Climate Change to adopt 
the Paris Agreement.\1\
---------------------------------------------------------------------------
    \1\ Decision 1/CP.21, paragraph 21.
---------------------------------------------------------------------------
    The IPCC accepted the invitation in April 2016, deciding to prepare 
this Special Report on the impacts of global warming of 1.5 C above 
pre-industrial levels and related global greenhouse gas emission 
pathways, in the context of strengthening the global response to the 
threat of climate change, sustainable development, and efforts to 
eradicate poverty.
    This Summary for Policymakers (SPM) presents the key findings of 
the Special Report, based on the assessment of the available 
scientific, technical and socioeconomic literature \2\ relevant to 
global warming of 1.5 C and for the comparison between global warming 
of 1.5 C and 2 C above pre-industrial levels. The level of confidence 
associated with each key finding is reported using the IPCC calibrated 
language.\3\ The underlying scientific basis of each key finding is 
indicated by references provided to chapter elements. In the SPM, 
knowledge gaps are identified associated with the underlying chapters 
of the Report.
---------------------------------------------------------------------------
    \2\ The assessment covers literature accepted for publication by 15 
May 2018.
    \3\ Each finding is grounded in an evaluation of underlying 
evidence and agreement. A level of confidence is expressed using five 
qualifiers: very low, low, medium, high and very high, and typeset in 
italics, for example, medium confidence. The following terms have been 
used to indicate the assessed likelihood of an outcome or a result: 
virtually certain 99-100% probability, very likely 90-100%, likely 66-
100%, about as likely as not 33-66%, unlikely 0-33%, very unlikely 0-
10%, exceptionally unlikely 0-1%. Additional terms (extremely likely 
95-100%, more likely than not >50-100%, more unlikely than likely 0-
<50%, extremely unlikely 0-5%) may also be used when appropriate. 
Assessed likelihood is typeset in italics, for example, very likely. 
This is consistent with AR5.
---------------------------------------------------------------------------
A. Understanding Global Warming of 1.5 C \4\
---------------------------------------------------------------------------
    \4\ See also Box SPM.1: Core Concepts Central to this Special 
Report.
---------------------------------------------------------------------------
    A.1  Human activities are estimated to have caused approximately 
1.0 C of global warming \5\ above pre-industrial levels, with a likely 
range of 0.8 CC to 1.2 C. Global warming is likely to reach 1.5 C 
between 2030 and 2052 if it continues to increase at the current rate. 
(high confidence) (Figure SPM.1) (1.2)
---------------------------------------------------------------------------
    \5\ Present level of global warming is defined as the average of a 
30 year period centred on 2017 assuming the recent rate of warming 
continues.

    A.1.1  Reflecting the long-term warming trend since pre-industrial 
times, observed global mean surface temperature (GMST) for the decade 
2006-2015 was 0.87 C (likely between 0.75 C and 0.99 C) \6\ higher 
than the average over the 1850-1900 period (very high confidence). 
Estimated anthropogenic global warming matches the level of observed 
warming to within R20% (likely range). Estimated anthropogenic global 
warming is currently increasing at 0.2 C (likely between 0.1 C and 
0.3 C) per decade due to past and ongoing emissions (high confidence). 
(1.2.1, Table 1.1, 1.2.4)
---------------------------------------------------------------------------
    \6\ This range spans the four available peer-reviewed estimates of 
the observed GMST change and also accounts for additional uncertainty 
due to possible short-term natural variability. (1.2.1, Table 1.1)
---------------------------------------------------------------------------
    A.1.2  Warming greater than the global annual average is being 
experienced in many land regions and seasons, including two to three 
times higher in the Arctic. Warming is generally higher over land than 
over the ocean. (high confidence) (1.2.1, 1.2.2, Figure 1.1, Figure 
1.3, 3.3.1, 3.3.2)
    A.1.3  Trends in intensity and frequency of some climate and 
weather extremes have been detected over time spans during which about 
0.5 C of global warming occurred (medium confidence). This assessment 
is based on several lines of evidence, including attribution studies 
for changes in extremes since 1950. (3.3.1, 3.3.2, 3.3.3)

    A.2  Warming from anthropogenic emissions from the pre-industrial 
period to the present will persist for centuries to millennia and will 
continue to cause further long-term changes in the climate system, such 
as sea level rise, with associated impacts (high confidence), but these 
emissions alone are unlikely to cause global warming of 1.5 C (medium 
confidence). (Figure SPM.1) (1.2, 3.3, Figure 1.5)

    A.2.1  Anthropogenic emissions (including greenhouse gases, 
aerosols and their precursors) up to the present are unlikely to cause 
further warming of more than 0.5 C over the next two to 3 decades 
(high confidence) or on a century time scale (medium confidence). 
(1.2.4, Figure 1.5)
    A.2.2  Reaching and sustaining net zero global anthropogenic 
CO2 emissions and declining net non-CO2 radiative 
forcing would halt anthropogenic global warming on multi-decadal time 
scales (high confidence). The maximum temperature reached is then 
determined by cumulative net global anthropogenic CO2 
emissions up to the time of net zero CO2 emissions (high 
confidence) and the level of non-CO2 radiative forcing in 
the decades prior to the time that maximum temperatures are reached 
(medium confidence). On longer time scales, sustained net negative 
global anthropogenic CO2 emissions and/or further reductions 
in non-CO2 radiative forcing may still be required to 
prevent further warming due to Earth system feedbacks and to reverse 
ocean acidification (medium confidence) and will be required to 
minimize sea level rise (high confidence). (Cross-Chapter Box 2 in 
Chapter 1, 1.2.3, 1.2.4, Figure 1.4, 2.2.1, 2.2.2, 3.4.4.8, 3.4.5.1, 
3.6.3.2)

    A.3  Climate-related risks for natural and human systems are higher 
for global warming of 1.5 C than at present, but lower than at 2 C 
(high confidence). These risks depend on the magnitude and rate of 
warming, geographic location, levels of development and vulnerability, 
and on the choices and implementation of adaptation and mitigation 
options (high confidence). (Figure SPM.2) (1.3, 3.3, 3.4, 5.6)

    A.3.1  Impacts on natural and human systems from global warming 
have already been observed (high confidence). Many land and ocean 
ecosystems and some of the services they provide have already changed 
due to global warming (high confidence). (Figure SPM.2) (1.4, 3.4, 3.5)
    A.3.2  Future climate-related risks depend on the rate, peak and 
duration of warming. In the aggregate, they are larger if global 
warming exceeds 1.5 C before returning to that level by 2100 than if 
global warming gradually stabilizes at 
1.5 C, especially if the peak temperature is high (e.g., about 2 C) 
(high confidence). Some impacts may be long-lasting or irreversible, 
such as the loss of some ecosystems (high confidence). (3.2, 3.4.4, 
3.6.3, Cross-Chapter Box 8 in Chapter 3)
    A.3.3  Adaptation and mitigation are already occurring (high 
confidence). Future climate-related risks would be reduced by the 
upscaling and acceleration of far-reaching, multilevel and cross-
sectoral climate mitigation and by both incremental and 
transformational adaptation (high confidence). (1.2, 1.3, Table 3.5, 
4.2.2, Cross-Chapter Box 9 in Chapter 4, Box 4.2, Box 4.3, Box 4.6, 
4.3.1, 4.3.2, 4.3.3, 4.3.4, 4.3.5, 4.4.1, 4.4.4, 4.4.5, 4.5.3)
Cumulative emissions of CO2 and future non-CO2 
        radiative forcing determine the probability of limiting warming 
        to 1.5 C
(a) Observed global temperature change and modeled responses to 
        stylized anthropogenic emission and forcing pathways
Global warming relative to 1850-1900 (C)
Figure SPM.1



 
 
 
(b) Stylized net global   (c) Cumulative net CO2   (d) Non-CO2 radiative
 CO2 emission pathways           emissions            forcing pathways
 Billion tonnes CO2 per     Billion tonnes CO2    Watts per square metre
    year (GtCO2/yr)               (GtCO2)                 (W/m\2\)
 

                                                   
                                                   

 
 
 
    Faster immediate          Maximum temperature rise is determined by
 CO2 emission              cumulative net CO2 emissions and net non-CO2
 reductions limit            radiative forcing due to methane, nitrous
 cumulative CO2               oxide, aerosols and other anthropogenic
 emissions shown in                       forcing agents.
 panel (c).
 

          Panel a: Observed monthly global mean surface temperature 
        (GMST, grey line up to 2017, from the HadCRUT4, GISTEMP, 
        Cowtan-Way, and NOAA datasets) change and estimated 
        anthropogenic global warming (solid orange line up to 2017, 
        with orange shading indicating assessed likely range). Orange 
        dashed arrow and horizontal orange error bar show respectively 
        the central estimate and likely range of the time at which 1.5 
        C is reached if the current rate of warming continues. The 
        grey plume on the right of panel a shows the likely range of 
        warming responses, computed with a simple climate model, to a 
        stylized pathway (hypothetical future) in which net 
        CO2 emissions (grey line in panels b and c) decline 
        in a straight line from 2020 to reach net zero in 2055 and net 
        non-CO2 radiative forcing (grey line in panel d) 
        increases to 2030 and then declines. The blue plume in panel a) 
        shows the response to faster CO2 emissions 
        reductions (blue line in panel b), reaching net zero in 2040, 
        reducing cumulative CO2 emissions (panel c). The 
        purple plume shows the response to net CO2 emissions 
        declining to zero in 2055, with net non-CO2 forcing 
        remaining constant after 2030. The vertical error bars on right 
        of panel a) show the likely ranges (thin lines) and central 
        terciles (33rd-66th percentiles, thick lines) of the estimated 
        distribution of warming in 2100 under these three stylized 
        pathways. Vertical dotted error bars in panels b, c and d show 
        the likely range of historical annual and cumulative global net 
        CO2 emissions in 2017 (data from the Global Carbon 
        Project) and of net non-CO2 radiative forcing in 
        2011 from AR5, respectively. Vertical axes in panels c and d 
        are scaled to represent approximately equal effects on GMST. 
        (1.2.1, 1.2.3, 1.2.4, 2.3, Figure 1.2 and Chapter 1 
        Supplementary Material, Cross-Chapter Box 2 in Chapter 1)
B. Projected Climate Change, Potential Impacts and Associated Risks
    B.1  Climate models project robust \7\ differences in regional 
climate characteristics between present-day and global warming of 1.5 
C,\8\ and between 1.5 C and 2 C.\8\ These differences include 
increases in: mean temperature in most land and ocean regions (high 
confidence), hot extremes in most inhabited regions (high confidence), 
heavy precipitation in several regions (medium confidence), and the 
probability of drought and precipitation deficits in some regions 
(medium confidence). (3.3)
---------------------------------------------------------------------------
    \7\ Robust is here used to mean that at least \2/3\ of climate 
models show the same sign of changes at the grid point scale, and that 
differences in large regions are statistically significant.
    \8\ Projected changes in impacts between different levels of global 
warming are determined with respect to changes in global mean surface 
air temperature.

    B.1.1  Evidence from attributed changes in some climate and weather 
extremes for a global warming of about 0.5 C supports the assessment 
that an additional 0.5 C of warming compared to present is associated 
with further detectable changes in these extremes (medium confidence). 
Several regional changes in climate are assessed to occur with global 
warming up to 1.5 C compared to pre-industrial levels, including 
warming of extreme temperatures in many regions (high confidence), 
increases in frequency, intensity, and/or amount of heavy precipitation 
in several regions (high confidence), and an increase in intensity or 
frequency of droughts in some regions (medium confidence). (3.2, 3.3.1, 
3.3.2, 3.3.3, 3.3.4, Table 3.2)
    B.1.2  Temperature extremes on land are projected to warm more than 
GMST (high confidence): extreme hot days in mid-latitudes warm by up to 
about 3 C at global warming of 1.5 C and about 4 C at 2 C, and 
extreme cold nights in high latitudes warm by up to about 4.5 C at 1.5 
C and about 6 C at 2 C (high confidence). The number of hot days is 
projected to increase in most land regions, with highest increases in 
the tropics (high confidence). (3.3.1, 3.3.2, Cross-Chapter Box 8 in 
Chapter 3)
    B.1.3  Risks from droughts and precipitation deficits are projected 
to be higher at 2 C compared to 1.5 C of global warming in some 
regions (medium confidence). Risks from heavy precipitation events are 
projected to be higher at 2 C compared to 1.5 C of global warming in 
several northern hemisphere high-latitude and/or high-elevation 
regions, eastern Asia and eastern North America (medium confidence). 
Heavy precipitation associated with tropical cyclones is projected to 
be higher at 2 C compared to 1.5 C global warming (medium 
confidence). There is generally low confidence in projected changes in 
heavy precipitation at 2 C compared to 1.5 C in other regions. Heavy 
precipitation when aggregated at global scale is projected to be higher 
at 2 C than at 1.5 C of global warming (medium confidence). As a 
consequence of heavy precipitation, the fraction of the global land 
area affected by flood hazards is projected to be larger at 2 C 
compared to 1.5 C of global warming (medium confidence). (3.3.1, 
3.3.3, 3.3.4, 3.3.5, 3.3.6)

    B.2  By 2100, global mean sea level rise is projected to be around 
0.1 metre lower with global warming of 1.5 C compared to 2 C (medium 
confidence). Sea level will continue to rise well beyond 2100 (high 
confidence), and the magnitude and rate of this rise depend on future 
emission pathways. A slower rate of sea level rise enables greater 
opportunities for adaptation in the human and ecological systems of 
small islands, low-lying coastal areas and deltas (medium confidence). 
(3.3, 3.4, 3.6)

    B.2.1  Model-based projections of global mean sea level rise 
(relative to 1986-2005) suggest an indicative range of 0.26 to 0.77 m 
by 2100 for 1.5 C of global warming, 0.1 m (0.04-0.16 m) less than for 
a global warming of 2 C (medium confidence). A reduction of 0.1 m in 
global sea level rise implies that up to ten million fewer people would 
be exposed to related risks, based on population in the year 2010 and 
assuming no adaptation (medium confidence). (3.4.4, 3.4.5, 4.3.2)
    B.2.2  Sea level rise will continue beyond 2100 even if global 
warming is limited to 1.5 C in the 21st century (high confidence). 
Marine ice sheet instability in Antarctica and/or irreversible loss of 
the Greenland ice sheet could result in multi-metre rise in sea level 
over hundreds to thousands of years. These instabilities could be 
triggered at around 1.5 C to 2 C of global warming (medium 
confidence). (Figure SPM.2) (3.3.9, 3.4.5, 3.5.2, 3.6.3, Box 3.3)
    B.2.3  Increasing warming amplifies the exposure of small islands, 
low-lying coastal areas and deltas to the risks associated with sea 
level rise for many human and ecological systems, including increased 
saltwater intrusion, flooding and damage to infrastructure (high 
confidence). Risks associated with sea level rise are higher at 2 C 
compared to 1.5 C. The slower rate of sea level rise at global warming 
of 1.5 C reduces these risks, enabling greater opportunities for 
adaptation including managing and restoring natural coastal ecosystems 
and infrastructure reinforcement (medium confidence). (Figure SPM.2) 
(3.4.5, Box 3.5)

    B.3  On land, impacts on biodiversity and ecosystems, including 
species loss and extinction, are projected to be lower at 1.5 C of 
global warming compared to 2 C. Limiting global warming to 1.5 C 
compared to 2 C is projected to lower the impacts on terrestrial, 
freshwater and coastal ecosystems and to retain more of their services 
to humans (high confidence). (Figure SPM.2) (3.4, 3.5, Box 3.4, Box 
4.2, Cross-Chapter Box 8 in Chapter 3)

    B.3.1  Of 105,000 species studied,\9\ 6% of insects, 8% of plants 
and 4% of vertebrates are projected to lose over half of their 
climatically determined geographic range for global warming of 1.5 C, 
compared with 18% of insects, 16% of plants and 8% of vertebrates for 
global warming of 2 C (medium confidence). Impacts associated with 
other biodiversity-related risks such as forest fires and the spread of 
invasive species are lower at 1.5 C compared to 2 C of global warming 
(high confidence). (3.4.3, 3.5.2)
---------------------------------------------------------------------------
    \9\ Consistent with earlier studies, illustrative numbers were 
adopted from one recent meta-study.
---------------------------------------------------------------------------
    B.3.2  Approximately 4% (interquartile range 2-7%) of the global 
terrestrial land area is projected to undergo a transformation of 
ecosystems from one type to another at 1 C of global warming, compared 
with 13% (interquartile range 8-20%) at 2 C (medium confidence). This 
indicates that the area at risk is projected to be approximately 50% 
lower at 1.5 C compared to 2 C (medium confidence). (3.4.3.1, 
3.4.3.5)
    B.3.3  High-latitude tundra and boreal forests are particularly at 
risk of climate change-induced degradation and loss, with woody shrubs 
already encroaching into the tundra (high confidence) and this will 
proceed with further warming. Limiting global warming to 1.5 C rather 
than 2 C is projected to prevent the thawing over centuries of a 
permafrost area in the range of 1.5 to 2.5 million km\2\ (medium 
confidence). (3.3.2, 3.4.3, 3.5.5)

    B.4  Limiting global warming to 1.5 C compared to 2 C is 
projected to reduce increases in ocean temperature as well as 
associated increases in ocean acidity and decreases in ocean oxygen 
levels (high confidence). Consequently, limiting global warming to 1.5 
C is projected to reduce risks to marine biodiversity, fisheries, and 
ecosystems, and their functions and services to humans, as illustrated 
by recent changes to Arctic sea ice and warm-water coral reef 
ecosystems (high confidence). (3.3, 3.4, 3.5, Box 3.4, Box 3.5)

    B.4.1  There is high confidence that the probability of a sea ice-
free Arctic Ocean during summer is substantially lower at global 
warming of 1.5 C when compared to 2 C. With 1.5 C of global warming, 
one sea ice-free Arctic summer is projected per century. This 
likelihood is increased to at least one per decade with 2 C global 
warming. Effects of a temperature overshoot are reversible for Arctic 
sea ice cover on decadal time scales (high confidence). (3.3.8, 
3.4.4.7)
    B.4.2  Global warming of 1.5 C is projected to shift the ranges of 
many marine species to higher latitudes as well as increase the amount 
of damage to many ecosystems. It is also expected to drive the loss of 
coastal resources and reduce the productivity of fisheries and 
aquaculture (especially at low latitudes). The risks of climate-induced 
impacts are projected to be higher at 2 C than those at global warming 
of 1.5 C (high confidence). Coral reefs, for example, are projected to 
decline by a further 70-90% at 1.5 C (high confidence) with larger 
losses (>99%) at 2 C (very high confidence). The risk of irreversible 
loss of many marine and coastal ecosystems increases with global 
warming, especially at 2 C or more (high confidence). (3.4.4, Box 3.4)
    B.4.3  The level of ocean acidification due to increasing 
CO2 concentrations associated with global warming of 1.5 C 
is projected to amplify the adverse effects of warming, and even 
further at 2 C, impacting the growth, development, calcification, 
survival, and thus abundance of a broad range of species, for example, 
from algae to fish (high confidence). (3.3.10, 3.4.4)
    B.4.4  Impacts of climate change in the ocean are increasing risks 
to fisheries and aquaculture via impacts on the physiology, 
survivorship, habitat, reproduction, disease incidence, and risk of 
invasive species (medium confidence) but are projected to be less at 
1.5 C of global warming than at 2 C. One global fishery model, for 
example, projected a decrease in global annual catch for marine 
fisheries of about 1.5 million tonnes for 1.5 C of global warming 
compared to a loss of more than 3 million tonnes for 2 C of global 
warming (medium confidence). (3.4.4, Box 3.4)

    B.5  Climate-related risks to health, livelihoods, food security, 
water supply, human security, and economic growth are projected to 
increase with global warming of 1.5 C and increase further with 2 C. 
(Figure SPM.2) (3.4, 3.5, 5.2, Box 3.2, Box 3.3, Box 3.5, Box 3.6, 
Cross-Chapter Box 6 in Chapter 3, Cross-Chapter Box 9 in Chapter 4, 
Cross-Chapter Box 12 in Chapter 5, 5.2)

    B.5.1  Populations at disproportionately higher risk of adverse 
consequences with global warming of 1.5 C and beyond include 
disadvantaged and vulnerable populations, some indigenous peoples, and 
local communities dependent on agricultural or coastal livelihoods 
(high confidence). Regions at disproportionately higher risk include 
Arctic ecosystems, dryland regions, small island developing states, and 
Least Developed Countries (high confidence). Poverty and disadvantage 
are expected to increase in some populations as global warming 
increases; limiting global warming to 1.5 C, compared with 2 C, could 
reduce the number of people both exposed to climate-related risks and 
susceptible to poverty by up to several hundred million by 2050 (medium 
confidence). (3.4.10, 3.4.11, Box 3.5, Cross-Chapter Box 6 in Chapter 
3, Cross-Chapter Box 9 in Chapter 4, Cross-Chapter Box 12 in Chapter 5, 
4.2.2.2, 5.2.1, 5.2.2, 5.2.3, 5.6.3)
    B.5.2  Any increase in global warming is projected to affect human 
health, with primarily negative consequences (high confidence). Lower 
risks are projected at 1.5 C than at 2 C for heat-related morbidity 
and mortality (very high confidence) and for ozone-related mortality if 
emissions needed for ozone formation remain high (high confidence). 
Urban heat islands often amplify the impacts of heatwaves in cities 
(high confidence). Risks from some vector-borne diseases, such as 
malaria and dengue fever, are projected to increase with warming from 
1.5 C to 2 C, including potential shifts in their geographic range 
(high confidence). (3.4.7, 3.4.8, 3.5.5.8)
    B.5.3  Limiting warming to 1.5 C compared with 2 C is projected 
to result in smaller net reductions in yields of maize, rice, wheat, 
and potentially other cereal crops, particularly in sub-Saharan Africa, 
Southeast Asia, and Central and South America, and in the 
CO2-dependent nutritional quality of rice and wheat (high 
confidence). Reductions in projected food availability are larger at 2 
C than at 1.5 C of global warming in the Sahel, southern Africa, the 
Mediterranean, central Europe, and the Amazon (medium confidence). 
Livestock are projected to be adversely affected with rising 
temperatures, depending on the extent of changes in feed quality, 
spread of diseases, and water resource availability (high confidence). 
(3.4.6, 3.5.4, 3.5.5, Box 3.1, Cross-Chapter Box 6 in Chapter 3, Cross-
Chapter Box 9 in Chapter 4)
    B.5.4  Depending on future socioeconomic conditions, limiting 
global warming to 1.5 C compared to 2 C may reduce the proportion of 
the world population exposed to a climate change-induced increase in 
water stress by up to 50%, although there is considerable variability 
between regions (medium confidence). Many small island developing 
states could experience lower water stress as a result of projected 
changes in aridity when global warming is limited to 1.5 C, as 
compared to 2 C (medium confidence). (3.3.5, 3.4.2, 3.4.8, 3.5.5, Box 
3.2, Box 3.5, Cross-Chapter Box 9 in Chapter 4)
    B.5.5  Risks to global aggregated economic growth due to climate 
change impacts are projected to be lower at 1.5 C than at 2 C by the 
end of this century \10\ (medium confidence). This excludes the costs 
of mitigation, adaptation investments and the benefits of adaptation. 
Countries in the tropics and Southern Hemisphere subtropics are 
projected to experience the largest impacts on economic growth due to 
climate change should global warming increase from 1.5 C to 2 C 
(medium confidence). (3.5.2, 3.5.3)
---------------------------------------------------------------------------
    \10\ Here, impacts on economic growth refer to changes in gross 
domestic product (GDP). Many impacts, such as loss of human lives, 
cultural heritage and ecosystem services, are difficult to value and 
monetize.
---------------------------------------------------------------------------
    B.5.6  Exposure to multiple and compound climate-related risks 
increases between 1.5 C and 2 C of global warming, with greater 
proportions of people both so exposed and susceptible to poverty in 
Africa and Asia (high confidence). For global warming from 1.5 C to 2 
C, risks across energy, food, and water sectors could overlap 
spatially and temporally, creating new and exacerbating current 
hazards, exposures, and vulnerabilities that could affect increasing 
numbers of people and regions (medium confidence). (Box 3.5, 3.3.1, 
3.4.5.3, 3.4.5.6, 3.4.11, 3.5.4.9)
    B.5.7  There are multiple lines of evidence that since AR5 the 
assessed levels of risk increased for four of the five Reasons for 
Concern (RFCs) for global warming to 2 C (high confidence). The risk 
transitions by degrees of global warming are now: from high to very 
high risk between 1.5 C and 2 C for RFC1 (Unique and threatened 
systems) (high confidence); from moderate to high risk between 1 C and 

1.5 C for RFC2 (Extreme weather events) (medium confidence); from 
moderate to high risk between 1.5 C and 2 C for RFC3 (Distribution of 
impacts) (high confidence); from moderate to high risk between 1.5 C 
and 2.5 C for RFC4 (Global aggregate impacts) (medium confidence); and 
from moderate to high risk between 1 C and 2.5 C for RFC5 (Large-
scale singular events) (medium confidence). (Figure SPM.2) (3.4.13; 
3.5, 3.5.2)

    B.6  Most adaptation needs will be lower for global warming of 1.5 
C compared to 2 C (high confidence). There are a wide range of 
adaptation options that can reduce the risks of climate change (high 
confidence). There are limits to adaptation and adaptive capacity for 
some human and natural systems at global warming of 1.5 C, with 
associated losses (medium confidence). The number and availability of 
adaptation options vary by sector (medium confidence). (Table 3.5, 4.3, 
4.5, Cross-Chapter Box 9 in Chapter 4, Cross-Chapter Box 12 in Chapter 
5)

    B.6.1  A wide range of adaptation options are available to reduce 
the risks to natural and managed ecosystems (e.g., ecosystem-based 
adaptation, ecosystem restoration and avoided degradation and 
deforestation, biodiversity management, sustainable aquaculture, and 
local knowledge and indigenous knowledge), the risks of sea level rise 
(e.g., coastal defence and hardening), and the risks to health, 
livelihoods, food, water, and economic growth, especially in rural 
landscapes (e.g., efficient irrigation, social safety nets, disaster 
risk management, risk spreading and sharing, and community-based 
adaptation) and urban areas (e.g., green infrastructure, sustainable 
land use and planning, and sustainable water management) (medium 
confidence). (4.3.1, 4.3.2, 4.3.3, 4.3.5, 4.5.3, 4.5.4, 5.3.2, Box 4.2, 
Box 4.3, Box 4.6, Cross-Chapter Box 9 in Chapter 4).
    B.6.2  Adaptation is expected to be more challenging for 
ecosystems, food and health systems at 2 C of global warming than for 
1.5 C (medium confidence). Some vulnerable regions, including small 
islands and Least Developed Countries, are projected to experience high 
multiple interrelated climate risks even at global warming of 1.5 C 
(high confidence). (3.3.1, 3.4.5, Box 3.5, Table 3.5, Cross-Chapter Box 
9 in Chapter 4, 5.6, Cross-Chapter Box 12 in Chapter 5, Box 5.3)
    B.6.3  Limits to adaptive capacity exist at 1.5 C of global 
warming, become more pronounced at higher levels of warming and vary by 
sector, with site-specific implications for vulnerable regions, 
ecosystems and human health (medium confidence). (Cross-Chapter Box 12 
in Chapter 5, Box 3.5, Table 3.5)
How the level of global warming affects impacts and/or risks associated 
        with the Reasons for Concern (RFCs) and selected natural, 
        managed and human systems
    Five Reasons For Concern (RFCs) illustrate the impacts and risks of 
different levels of global warming for people, economies and ecosystems 
across sectors and regions.
Figure SPM.2
Impacts and risks associated with the Reasons for Concern (RFCs)


Impacts and risks for selected natural, managed and human systems


          Confidence level for transition: L=Low, M=Medium, H=High, and 
        VH=Very high.
          Five integrative reasons for concern (RFCs) provide a 
        framework for summarizing key impacts and risks across sectors 
        and regions, and were introduced in the IPCC Third Assessment 
        Report. RFCs illustrate the implications of global warming for 
        people, economies and ecosystems. Impacts and/or risks for each 
        RFC are based on assessment of the new literature that has 
        appeared. As in AR5, this literature was used to make expert 
        judgments to assess the levels of global warming at which 
        levels of impact and/or risk are undetectable, moderate, high 
        or very high. The selection of impacts and risks to natural, 
        managed and human systems in the lower panel is illustrative 
        and is not intended to be fully comprehensive. (3.4, 3.5, 
        3.5.2.1, 3.5.2.2, 3.5.2.3, 3.5.2.4, 3.5.2.5, 5.4.1, 5.5.3, 
        5.6.1, Box 3.4)
          RFC1 Unique and threatened systems: ecological and human 
        systems that have restricted geographic ranges constrained by 
        climate-related conditions and have high endemism or other 
        distinctive properties. Examples include coral reefs, the 
        Arctic and its indigenous people, mountain glaciers and 
        biodiversity hotspots.
          RFC2 Extreme weather events: risks/impacts to human health, 
        livelihoods, assets and ecosystems from extreme weather events 
        such as heat waves, heavy rain, drought and associated 
        wildfires, and coastal flooding.
          RFC3 Distribution of impacts: risks/impacts that 
        disproportionately affect particular groups due to uneven 
        distribution of physical climate change hazards, exposure or 
        vulnerability.
          RFC4 Global aggregate impacts: global monetary damage, 
        global-scale degradation and loss of ecosystems and 
        biodiversity.
          RFC5 Large-scale singular events: are relatively large, 
        abrupt and sometimes irreversible changes in systems that are 
        caused by global warming. Examples include disintegration of 
        the Greenland and Antarctic ice sheets.
C. Emission Pathways and System Transitions Consistent with 1.5 C 
        Global Warming
    C.1  In model pathways with no or limited overshoot of 1.5 C, 
global net anthropogenic CO2 emissions decline by about 45% 
from 2010 levels by 2030 (40-60% interquartile range), reaching net 
zero around 2050 (2045-2055 interquartile range). For limiting global 
warming to below 2 C \11\ CO2 emissions are projected to 
decline by about 25% by 2030 in most pathways (10-30% interquartile 
range) and reach net zero around 2070 (2065-2080 interquartile range). 
Non-CO2 emissions in pathways that limit global warming to 
1.5 C show deep reductions that are similar to those in pathways 
limiting warming to 2 C. (high confidence) (Figure SPM.3a) (2.1, 2.3, 
Table 2.4)
---------------------------------------------------------------------------
    \11\ References to pathways limiting global warming to 2 C are 
based on a 66% probability of staying below 2 C.

    C.1.1  CO2 emissions reductions that limit global 
warming to 1.5 C with no or limited overshoot can involve different 
portfolios of mitigation measures, striking different balances between 
lowering energy and resource intensity, rate of decarbonization, and 
the reliance on carbon dioxide removal. Different portfolios face 
different implementation challenges and potential synergies and trade-
offs with sustainable development. (high confidence) (Figure SPM.3b) 
(2.3.2, 2.3.4, 2.4, 2.5.3)
    C.1.2  Modelled pathways that limit global warming to 1.5 C with 
no or limited overshoot involve deep reductions in emissions of methane 
and black carbon (35% or more of both by 2050 relative to 2010). These 
pathways also reduce most of the cooling aerosols, which partially 
offsets mitigation effects for 2 to 3 decades. Non-CO2 
emissions \12\ can be reduced as a result of broad mitigation measures 
in the energy sector. In addition, targeted non-CO2 
mitigation measures can reduce nitrous oxide and methane from 
agriculture, methane from the waste sector, some sources of black 
carbon, and hydrofluorocarbons. High bioenergy demand can increase 
emissions of nitrous oxide in some 1.5 C pathways, highlighting the 
importance of appropriate management approaches. Improved air quality 
resulting from projected reductions in many non-CO2 
emissions provide direct and immediate population health benefits in 
all 1.5 C model pathways. (high confidence) (Figure SPM.3a) (2.2.1, 
2.3.3, 2.4.4, 2.5.3, 4.3.6, 5.4.2)
---------------------------------------------------------------------------
    \12\ Non-CO2 emissions included in this Report are all 
anthropogenic emissions other than CO2 that result in 
radiative forcing. These include short-lived climate forcers, such as 
methane, some fluorinated gases, ozone precursors, aerosols or aerosol 
precursors, such as black carbon and sulphur dioxide, respectively, as 
well as long-lived greenhouse gases, such as nitrous oxide or some 
fluorinated gases. The radiative forcing associated with non-
CO2 emissions and changes in surface albedo is referred to 
as non-CO2 radiative forcing. (2.2.1)
---------------------------------------------------------------------------
    C.1.3  Limiting global warming requires limiting the total 
cumulative global anthropogenic emissions of CO2 since the 
preindustrial period, that is, staying within a total carbon budget 
(high confidence).\13\ By the end of 2017, anthropogenic CO2 
emissions since the pre-industrial period are estimated to have reduced 
the total carbon budget for 1.5 C by approximately 2200 R 320 
GtCO2 (medium confidence). The associated remaining budget 
is being depleted by current emissions of 42 R 3 GtCO2 per 
year (high confidence). The choice of the measure of global temperature 
affects the estimated remaining carbon budget. Using global mean 
surface air temperature, as in AR5, gives an estimate of the remaining 
carbon budget of 580 GtCO2 for a 50% probability of limiting 
warming to 1.5 C, and 420 GtCO2 for a 66% probability 
(medium confidence).\14\ Alternatively, using GMST gives estimates of 
770 and 570 GtCO2, for 50% and 66% probabilities,\15\ 
respectively (medium confidence). Uncertainties in the size of these 
estimated remaining carbon budgets are substantial and depend on 
several factors. Uncertainties in the climate response to 
CO2 and non-CO2 emissions contribute R400 
GtCO2 and the level of historic warming contributes R250 
GtCO2 (medium confidence). Potential additional carbon 
release from future permafrost thawing and methane release from 
wetlands would reduce budgets by up to 100 GtCO2 over the 
course of this century and more thereafter (medium confidence). In 
addition, the level of non-CO2 mitigation in the future 
could alter the remaining carbon budget by 250 GtCO2 in 
either direction (medium confidence). (1.2.4, 2.2.2, 2.6.1, Table 2.2, 
Chapter 2 Supplementary Material)
---------------------------------------------------------------------------
    \13\ There is a clear scientific basis for a total carbon budget 
consistent with limiting global warming to 1.5 C. However, neither 
this total carbon budget nor the fraction of this budget taken up by 
past emissions were assessed in this Report.
    \14\ Irrespective of the measure of global temperature used, 
updated understanding and further advances in methods have led to an 
increase in the estimated remaining carbon budget of about 300 
GtCO2 compared to AR5. (medium confidence) (2.2.2)
    \15\ These estimates use observed GMST to 2006-2015 and estimate 
future temperature changes using near surface air temperatures.
---------------------------------------------------------------------------
    C.1.4  Solar radiation modification (SRM) measures are not included 
in any of the available assessed pathways. Although some SRM measures 
may be theoretically effective in reducing an overshoot, they face 
large uncertainties and knowledge gaps as well as substantial risks and 
institutional and social constraints to deployment related to 
governance, ethics, and impacts on sustainable development. They also 
do not mitigate ocean acidification. (medium confidence) (4.3.8, Cross-
Chapter Box 10 in Chapter 4)
Global Emissions Pathway Characteristics
    General characteristics of the evolution of anthropogenic net 
emissions of CO2, and total emissions of methane, black 
carbon, and nitrous oxide in model pathways that limit global warming 
to 1.5 C with no or limited overshoot. Net emissions are defined as 
anthropogenic emissions reduced by anthropogenic removals. Reductions 
in net emissions can be achieved through different portfolios of 
mitigation measures illustrated in Figure SPM.3b.
Figure SPM.3a


          Global emissions pathway characteristics. The main panel 
        shows global net anthropogenic CO2 emissions in 
        pathways limiting global warming to 1.5 C with no or limited 
        (less than 0.1 C) overshoot and pathways with higher 
        overshoot. The shaded area shows the full range for pathways 
        analysed in this Report. The panels on the right show non-
        CO2 emissions ranges for three compounds with large 
        historical forcing and a substantial portion of emissions 
        coming from sources distinct from those central to 
        CO2 mitigation. Shaded areas in these panels show 
        the 5-95% (light shading) and interquartile (dark shading) 
        ranges of pathways limiting global warming to 1.5 C with no or 
        limited overshoot. Box and whiskers at the bottom of the figure 
        show the timing of pathways reaching global net zero 
        CO2 emission levels, and a comparison with pathways 
        limiting global warming to 2 C with at least 66% probability. 
        Four illustrative model pathways are highlighted in the main 
        panel and are labelled P1, P2, P3 and P4, corresponding to the 
        LED, S1, S2, and S5 pathways assessed in Chapter 2. 
        Descriptions and characteristics of these pathways are 
        available in Figure SPM.3b. (2.1, 2.2, 2.3, Figure 2.5, Figure 
        2.10, Figure 2.11)
Characteristics of Four Illustrative Model Pathways
    Different mitigation strategies can achieve the net emissions 
reductions that would be required to follow a pathway that limits 
global warming to 1.5 C with no or limited overshoot. All pathways use 
Carbon Dioxide Removal (CDR), but the amount varies across pathways, as 
do the relative contributions of Bioenergy with Carbon Capture and 
Storage (BECCS) and removals in the Agriculture, Forestry and Other 
Land Use (AFOLU) sector. This has implications for emissions and 
several other pathway characteristics.
Figure SPM.3b
Breakdown of contributions to global net CO2 emissions in 
        four illustrative model pathways
        
        
          Characteristics of four illustrative model pathways in 
        relation to global warming of 1.5 C introduced in Figure 
        SPM.3a. These pathways were selected to show a range of 
        potential mitigation approaches and vary widely in their 
        projected energy and land use, as well as their assumptions 
        about future socioeconomic developments, including economic and 
        population growth, equity and sustainability. A breakdown of 
        the global net anthropogenic CO2 emissions into the 
        contributions in terms of CO2 emissions from fossil 
        fuel and industry; agriculture, forestry and other land use 
        (AFOLU); and bioenergy with carbon capture and storage (BECCS) 
        is shown. AFOLU estimates reported here are not necessarily 
        comparable with countries' estimates. Further characteristics 
        for each of these pathways are listed below each pathway. These 
        pathways illustrate relative global differences in mitigation 
        strategies, but do not represent central estimates, national 
        strategies, and do not indicate requirements. For comparison, 
        the right-most column shows the interquartile ranges across 
        pathways with no or limited overshoot of 1.5 C. Pathways P1, 
        P2, P3 and P4 correspond to the LED, S1, S2 and S5 pathways 
        assessed in Chapter 2 (Figure SPM.3a). (2.2.1, 2.3.1, 2.3.2, 
        2.3.3, 2.3.4, 2.4.1, 2.4.2, 2.4.4, 2.5.3, Figure 2.5, Figure 
        2.6, Figure 2.9, Figure 2.10, Figure 2.11, Figure 2.14, Figure 
        2.15, Figure 2.16, Figure 2.17, Figure 2.24, Figure 2.25, Table 
        2.4, Table 2.6, Table 2.7, Table 2.9, Table 4.1)

    C.2  Pathways limiting global warming to 1.5 C with no or limited 
overshoot would require rapid and far-reaching transitions in energy, 
land, urban and infrastructure (including transport and buildings), and 
industrial systems (high confidence). These systems transitions are 
unprecedented in terms of scale, but not necessarily in terms of speed, 
and imply deep emissions reductions in all sectors, a wide portfolio of 
mitigation options and a significant upscaling of investments in those 
options (medium confidence). (2.3, 2.4, 2.5, 4.2, 4.3, 4.4, 4.5)

    C.2.1  Pathways that limit global warming to 1.5 C with no or 
limited overshoot show system changes that are more rapid and 
pronounced over the next 2 decades than in 2 C pathways (high 
confidence). The rates of system changes associated with limiting 
global warming to 1.5 C with no or limited overshoot have occurred in 
the past within specific sectors, technologies and spatial contexts, 
but there is no documented historic precedent for their scale (medium 
confidence). (2.3.3, 2.3.4, 2.4, 2.5, 4.2.1, 4.2.2, Cross-Chapter Box 
11 in Chapter 4)
    C.2.2  In energy systems, modelled global pathways (considered in 
the literature) limiting global warming to 1.5 C with no or limited 
overshoot (for more details see Figure SPM.3b) generally meet energy 
service demand with lower energy use, including through enhanced energy 
efficiency, and show faster electrification of energy end use compared 
to 2 C (high confidence). In 1.5 C pathways with no or limited 
overshoot, low-emission energy sources are projected to have a higher 
share, compared with 2 C pathways, particularly before 2050 (high 
confidence). In 1.5 C pathways with no or limited overshoot, 
renewables are projected to supply 70-85% (interquartile range) of 
electricity in 2050 (high confidence). In electricity generation, 
shares of nuclear and fossil fuels with carbon dioxide capture and 
storage (CCS) are modelled to increase in most 1.5 C pathways with no 
or limited overshoot. In modelled 1.5 C pathways with limited or no 
overshoot, the use of CCS would allow the electricity generation share 
of gas to be approximately 8% (3-11% interquartile range) of global 
electricity in 2050, while the use of coal shows a steep reduction in 
all pathways and would be reduced to close to 0% (0-2% interquartile 
range) of electricity (high confidence). While acknowledging the 
challenges, and differences between the options and national 
circumstances, political, economic, social and technical feasibility of 
solar energy, wind energy and electricity storage technologies have 
substantially improved over the past few years (high confidence). These 
improvements signal a potential system transition in electricity 
generation. (Figure SPM.3b) (2.4.1, 2.4.2, Figure 2.1, Table 2.6, Table 
2.7, Cross-Chapter Box 6 in Chapter 3, 4.2.1, 4.3.1, 4.3.3, 4.5.2)
    C.2.3  CO2 emissions from industry in pathways limiting 
global warming to 1.5 C with no or limited overshoot are projected to 
be about 65-90% (interquartile range) lower in 2050 relative to 2010, 
as compared to 50-80% for global warming of 2 C (medium confidence). 
Such reductions can be achieved through combinations of new and 
existing technologies and practices, including electrification, 
hydrogen, sustainable biobased feedstocks, product substitution, and 
carbon capture, utilization and storage (CCUS). These options are 
technically proven at various scales but their large-scale deployment 
may be limited by economic, financial, human capacity and institutional 
constraints in specific contexts, and specific characteristics of 
large-scale industrial installations. In industry, emissions reductions 
by energy and process efficiency by themselves are insufficient for 
limiting warming to 1.5 C with no or limited overshoot (high 
confidence). (2.4.3, 4.2.1, Table 4.1, Table 4.3, 4.3.3, 4.3.4, 4.5.2)
    C.2.4  The urban and infrastructure system transition consistent 
with limiting global warming to 1.5 C with no or limited overshoot 
would imply, for example, changes in land and urban planning practices, 
as well as deeper emissions reductions in transport and buildings 
compared to pathways that limit global warming below 2 C (medium 
confidence). Technical measures and practices enabling deep emissions 
reductions include various energy efficiency options. In pathways 
limiting global warming to 1.5 C with no or limited overshoot, the 
electricity share of energy demand in buildings would be about 55-75% 
in 2050 compared to 50-70% in 2050 for 2 C global warming (medium 
confidence). In the transport sector, the share of low-emission final 
energy would rise from less than 5% in 2020 to about 35-65% in 2050 
compared to 25-45% for 2 C of global warming (medium confidence). 
Economic, institutional and socio-cultural barriers may inhibit these 
urban and infrastructure system transitions, depending on national, 
regional and local circumstances, capabilities and the availability of 
capital (high confidence). (2.3.4, 2.4.3, 4.2.1, Table 4.1, 4.3.3, 
4.5.2)
    C.2.5  Transitions in global and regional land use are found in all 
pathways limiting global warming to 1.5 C with no or limited 
overshoot, but their scale depends on the pursued mitigation portfolio. 
Model pathways that limit global warming to 1.5 C with no or limited 
overshoot project a 4 million km\2\ reduction to a 2.5 million km\2\ 
increase of non-pasture agricultural land for food and feed crops and a 
0.5-11 million km\2\ reduction of pasture land, to be converted into a 
0-6 million km\2\ increase of agricultural land for energy crops and a 
2 million km\2\ reduction to 9.5 million km\2\ increase in forests by 
2050 relative to 2010 (medium confidence).\16\ Land-use transitions of 
similar magnitude can be observed in modelled 2 C pathways (medium 
confidence). Such large transitions pose profound challenges for 
sustainable management of the various demands on land for human 
settlements, food, livestock feed, fibre, bioenergy, carbon storage, 
biodiversity and other ecosystem services (high confidence). Mitigation 
options limiting the demand for land include sustainable 
intensification of land-use practices, ecosystem restoration and 
changes towards less resource-intensive diets (high confidence). The 
implementation of land-based mitigation options would require 
overcoming socioeconomic, institutional, technological, financing and 
environmental barriers that differ across regions (high confidence). 
(2.4.4, Figure 2.24, 4.3.2, 4.3.7, 4.5.2, Cross-Chapter Box 7 in 
Chapter 3)
---------------------------------------------------------------------------
    \16\ The projected land-use changes presented are not deployed to 
their upper limits simultaneously in a single pathway.
---------------------------------------------------------------------------
    C.2.6  Additional annual average energy-related investments for the 
period 2016 to 2050 in pathways limiting warming to 1.5 C compared to 
pathways without new climate policies beyond those in place today are 
estimated to be around 830 billion USD2010 (range of 150 billion to 
1,700 billion USD2010 across six models \17\). This compares to total 
annual average energy supply investments in 1.5 C pathways of 1460 to 
3510 billion USD2010 and total annual average energy demand investments 
of 640 to 910 billion USD2010 for the period 2016 to 2050. Total 
energy-related investments increase by about 12% (range of 3% to 24%) 
in 1.5 C pathways relative to 2 C pathways. Annual investments in 
low-carbon energy technologies and energy efficiency are upscaled by 
roughly a factor of six (range of factor of 4 to 10) by 2050 compared 
to 2015 (medium confidence). (2.5.2, Box 4.8, Figure 2.27)
---------------------------------------------------------------------------
    \17\ Including two pathways limiting warming to 1.5 C with no or 
limited overshoot and four pathways with higher overshoot.
---------------------------------------------------------------------------
    C.2.7  Modelled pathways limiting global warming to 1.5 C with no 
or limited overshoot project a wide range of global average discounted 
marginal abatement costs over the 21st century. They are roughly 3-4 
times higher than in pathways limiting global warming to below 2 C 
(high confidence). The economic literature distinguishes marginal 
abatement costs from total mitigation costs in the economy. The 
literature on total mitigation costs of 1.5 C mitigation pathways is 
limited and was not assessed in this Report. Knowledge gaps remain in 
the integrated assessment of the economy-wide costs and benefits of 
mitigation in line with pathways limiting warming to 1.5 C. (2.5.2; 
2.6; Figure 2.26)

    C.3  All pathways that limit global warming to 1.5 C with limited 
or no overshoot project the use of carbon dioxide removal (CDR) on the 
order of 100-1,000 GtCO2 over the 21st century. CDR would be 
used to compensate for residual emissions and, in most cases, achieve 
net negative emissions to return global warming to 1.5 C following a 
peak (high confidence). CDR deployment of several hundreds of 
GtCO2 is subject to multiple feasibility and sustainability 
constraints (high confidence). Significant near-term emissions 
reductions and measures to lower energy and land demand can limit CDR 
deployment to a few hundred GtCO2 without reliance on 
bioenergy with carbon capture and storage (BECCS) (high confidence). 
(2.3, 2.4, 3.6.2, 4.3, 5.4)

    C.3.1  Existing and potential CDR measures include afforestation 
and reforestation, land restoration and soil carbon sequestration, 
BECCS, direct air carbon capture and storage (DACCS), enhanced 
weathering and ocean alkalinization. These differ widely in terms of 
maturity, potentials, costs, risks, co-benefits and trade-offs (high 
confidence). To date, only a few published pathways include CDR 
measures other than afforestation and BECCS. (2.3.4, 3.6.2, 4.3.2, 
4.3.7)
    C.3.2  In pathways limiting global warming to 1.5 C with limited 
or no overshoot, BECCS deployment is projected to range from 0-1, 0-8, 
and 0-16 GtCO2 yr-1 in 2030, 2050, and 2100, 
respectively, while agriculture, forestry and land-use (AFOLU) related 
CDR measures are projected to remove 0-5, 1-11, and 1-5 
GtCO2 yr-1 in these years (medium confidence). 
The upper end of these deployment ranges by mid-century exceeds the 
BECCS potential of up to 5 GtCO2 yr-1 and 
afforestation potential of up to 3.6 GtCO2 yr-1 
assessed based on recent literature (medium confidence). Some pathways 
avoid BECCS deployment completely through demand-side measures and 
greater reliance on AFOLU-related CDR measures (medium confidence). The 
use of bioenergy can be as high or even higher when BECCS is excluded 
compared to when it is included due to its potential for replacing 
fossil fuels across sectors (high confidence). (Figure SPM.3b) (2.3.3, 
2.3.4, 2.4.2, 3.6.2, 4.3.1, 4.2.3, 4.3.2, 4.3.7, 4.4.3, Table 2.4)
    C.3.3  Pathways that overshoot 1.5 C of global warming rely on CDR 
exceeding residual CO2 emissions later in the century to 
return to below 1.5 C by 2100, with larger overshoots requiring 
greater amounts of CDR (Figure SPM.3b) (high confidence). Limitations 
on the speed, scale, and societal acceptability of CDR deployment hence 
determine the ability to return global warming to below 1.5 C 
following an overshoot. Carbon cycle and climate system understanding 
is still limited about the effectiveness of net negative emissions to 
reduce temperatures after they peak (high confidence). (2.2, 2.3.4, 
2.3.5, 2.6, 4.3.7, 4.5.2, Table 4.11)
    C.3.4  Most current and potential CDR measures could have 
significant impacts on land, energy, water or nutrients if deployed at 
large scale (high confidence). Afforestation and bioenergy may compete 
with other land uses and may have significant impacts on agricultural 
and food systems, biodiversity, and other ecosystem functions and 
services (high confidence). Effective governance is needed to limit 
such trade-offs and ensure permanence of carbon removal in terrestrial, 
geological and ocean reservoirs (high confidence). Feasibility and 
sustainability of CDR use could be enhanced by a portfolio of options 
deployed at substantial, but lesser scales, rather than a single option 
at very large scale (high confidence). (Figure SPM.3b) (2.3.4, 2.4.4, 
2.5.3, 2.6, 3.6.2, 4.3.2, 4.3.7, 4.5.2, 5.4.1, 5.4.2; Cross-Chapter 
Boxes 7 and 8 in Chapter 3, Table 4.11, Table 5.3, Figure 5.3)
    C.3.5  Some AFOLU-related CDR measures such as restoration of 
natural ecosystems and soil carbon sequestration could provide co-
benefits such as improved biodiversity, soil quality, and local food 
security. If deployed at large scale, they would require governance 
systems enabling sustainable land management to conserve and protect 
land carbon stocks and other ecosystem functions and services (medium 
confidence). (Figure SPM.4) (2.3.3, 2.3.4, 2.4.2, 2.4.4, 3.6.2, 5.4.1, 
Cross-Chapter Boxes 3 in Chapter 1 and 7 in Chapter 3, 4.3.2, 4.3.7, 
4.4.1, 4.5.2, Table 2.4)
D. Strengthening the Global Response in the Context of Sustainable 
        Development and Efforts to Eradicate Poverty
    D.1  Estimates of the global emissions outcome of current 
nationally stated mitigation ambitions as submitted under the Paris 
Agreement would lead to global greenhouse gas emissions \18\ in 2030 of 
52-58 GtCO2eq yr-1 (medium confidence). Pathways 
reflecting these ambitions would not limit global warming to 1.5 C, 
even if supplemented by very challenging increases in the scale and 
ambition of emissions reductions after 2030 (high confidence). Avoiding 
overshoot and reliance on future large-scale deployment of carbon 
dioxide removal (CDR) can only be achieved if global CO2 
emissions start to decline well before 2030 (high confidence). (1.2, 
2.3, 3.3, 3.4, 4.2, 4.4, Cross-Chapter Box 11 in Chapter 4)
---------------------------------------------------------------------------
    \18\ GHG emissions have been aggregated with 100 year GWP values as 
introduced in the IPCC Second Assessment Report.

    D.1.1  Pathways that limit global warming to 1.5 C with no or 
limited overshoot show clear emission reductions by 2030 (high 
confidence). All but one show a decline in global greenhouse gas 
emissions to below 35 GtCO2eq yr-1 in 2030, and 
half of available pathways fall within the 25-30 GtCO2eq 
yr-1 range (interquartile range), a 40-50% reduction from 
2010 levels (high confidence). Pathways reflecting current nationally 
stated mitigation ambition until 2030 are broadly consistent with cost-
effective pathways that result in a global warming of about 3 C by 
2100, with warming continuing afterwards (medium confidence). (2.3.3, 
2.3.5, Cross-Chapter Box 11 in Chapter 4, 5.5.3.2)
    D.1.2  Overshoot trajectories result in higher impacts and 
associated challenges compared to pathways that limit global warming to 
1.5 C with no or limited overshoot (high confidence). Reversing 
warming after an overshoot of 0.2 C or larger during this century 
would require upscaling and deployment of CDR at rates and volumes that 
might not be achievable given considerable implementation challenges 
(medium confidence). (1.3.3, 2.3.4, 2.3.5, 2.5.1, 3.3, 4.3.7, Cross-
Chapter Box 8 in Chapter 3, Cross-Chapter Box 11 in Chapter 4)
    D.1.3  The lower the emissions in 2030, the lower the challenge in 
limiting global warming to 1.5 C after 2030 with no or limited 
overshoot (high confidence). The challenges from delayed actions to 
reduce greenhouse gas emissions include the risk of cost escalation, 
lock-in in carbon-emitting infrastructure, stranded assets, and reduced 
flexibility in future response options in the medium to long term (high 
confidence). These may increase uneven distributional impacts between 
countries at different stages of development (medium confidence). 
(2.3.5, 4.4.5, 5.4.2)

    D.2  The avoided climate change impacts on sustainable development, 
eradication of poverty and reducing inequalities would be greater if 
global warming were limited to 1.5 C rather than 2 C, if mitigation 
and adaptation synergies are maximized while trade-offs are minimized 
(high confidence). (1.1, 1.4, 2.5, 3.3, 3.4, 5.2, Table 5.1)

    D.2.1  Climate change impacts and responses are closely linked to 
sustainable development which balances social well-being, economic 
prosperity and environmental protection. The United Nations Sustainable 
Development Goals (SDGs), adopted in 2015, provide an established 
framework for assessing the links between global warming of 1.5 C or 2 
C and development goals that include poverty eradication, reducing 
inequalities, and climate action. (high confidence) (Cross-Chapter Box 
4 in Chapter 1, 1.4, 5.1)
    D.2.2  The consideration of ethics and equity can help address the 
uneven distribution of adverse impacts associated with 1.5 C and 
higher levels of global warming, as well as those from mitigation and 
adaptation, particularly for poor and disadvantaged populations, in all 
societies (high confidence). (1.1.1, 1.1.2, 1.4.3, 2.5.3, 3.4.10, 5.1, 
5.2, 5.3. 5.4, Cross-Chapter Box 4 in Chapter 1, Cross-Chapter Boxes 6 
and 8 in Chapter 3, and Cross-Chapter Box 12 in Chapter 5)
    D.2.3  Mitigation and adaptation consistent with limiting global 
warming to 
1.5 C are underpinned by enabling conditions, assessed in this Report 
across the geophysical, environmental-ecological, technological, 
economic, socio-cultural and institutional dimensions of feasibility. 
Strengthened multilevel governance, institutional capacity, policy 
instruments, technological innovation and transfer and mobilization of 
finance, and changes in human behaviour and lifestyles are enabling 
conditions that enhance the feasibility of mitigation and adaptation 
options for 1.5 C-consistent systems transitions. (high confidence) 
(1.4, Cross-Chapter Box 3 in Chapter 1, 2.5.1, 4.4, 4.5, 5.6)

    D.3  Adaptation options specific to national contexts, if carefully 
selected together with enabling conditions, will have benefits for 
sustainable development and poverty reduction with global warming of 
1.5 C, although trade-offs are possible (high confidence). (1.4, 4.3, 
4.5)

    D.3.1  Adaptation options that reduce the vulnerability of human 
and natural systems have many synergies with sustainable development, 
if well managed, such as ensuring food and water security, reducing 
disaster risks, improving health conditions, maintaining ecosystem 
services and reducing poverty and inequality (high confidence). 
Increasing investment in physical and social infrastructure is a key 
enabling condition to enhance the resilience and the adaptive 
capacities of societies. These benefits can occur in most regions with 
adaptation to 1.5 C of global warming (high confidence). (1.4.3, 
4.2.2, 4.3.1, 4.3.2, 4.3.3, 4.3.5, 4.4.1, 4.4.3, 4.5.3, 5.3.1, 5.3.2)
    D.3.2  Adaptation to 1.5 C global warming can also result in 
trade-offs or maladaptations with adverse impacts for sustainable 
development. For example, if poorly designed or implemented, adaptation 
projects in a range of sectors can increase greenhouse gas emissions 
and water use, increase gender and social inequality, undermine health 
conditions, and encroach on natural ecosystems (high confidence). These 
trade-offs can be reduced by adaptations that include attention to 
poverty and sustainable development (high confidence). (4.3.2, 4.3.3, 
4.5.4, 5.3.2; Cross-Chapter Boxes 6 and 7 in Chapter 3)
    D.3.3  A mix of adaptation and mitigation options to limit global 
warming to 
1.5 C, implemented in a participatory and integrated manner, can 
enable rapid, systemic transitions in urban and rural areas (high 
confidence). These are most effective when aligned with economic and 
sustainable development, and when local and regional governments and 
decision makers are supported by national governments (medium 
confidence). (4.3.2, 4.3.3, 4.4.1, 4.4.2)
    D.3.4  Adaptation options that also mitigate emissions can provide 
synergies and cost savings in most sectors and system transitions, such 
as when land management reduces emissions and disaster risk, or when 
low-carbon buildings are also designed for efficient cooling. Trade-
offs between mitigation and adaptation, when limiting global warming to 
1.5 C, such as when bioenergy crops, reforestation or afforestation 
encroach on land needed for agricultural adaptation, can undermine food 
security, livelihoods, ecosystem functions and services and other 
aspects of sustainable development. (high confidence) (3.4.3, 4.3.2, 
4.3.4, 4.4.1, 4.5.2, 4.5.3, 4.5.4)

    D.4  Mitigation options consistent with 1.5 C pathways are 
associated with multiple synergies and tradeoffs across the Sustainable 
Development Goals (SDGs). While the total number of possible synergies 
exceeds the number of trade-offs, their net effect will depend on the 
pace and magnitude of changes, the composition of the mitigation 
portfolio and the management of the transition. (high confidence) 
(Figure SPM.4) (2.5, 4.5, 5.4)

    D.4.1  1.5 C pathways have robust synergies particularly for the 
SDGs 3 (health), 7 (clean energy), 11 (cities and communities), 12 
(responsible consumption and production) and 14 (oceans) (very high 
confidence). Some 1.5 C pathways show potential trade-offs with 
mitigation for SDGs 1 (poverty), 2 (hunger), six (water) and 7 (energy 
access), if not managed carefully (high confidence). (Figure SPM.4) 
(5.4.2; Figure 5.4, Cross-Chapter Boxes 7 and 8 in Chapter 3)
    D.4.2  1.5 C pathways that include low energy demand (e.g., see P1 
in Figure SPM.3a and SPM.3b), low material consumption, and low GHG-
intensive food consumption have the most pronounced synergies and the 
lowest number of trade-offs with respect to sustainable development and 
the SDGs (high confidence). Such pathways would reduce dependence on 
CDR. In modelled pathways, sustainable development, eradicating poverty 
and reducing inequality can support limiting warming to 1.5 C (high 
confidence). (Figure SPM.3b, Figure SPM.4) (2.4.3, 2.5.1, 2.5.3, Figure 
2.4, Figure 2.28, 5.4.1, 5.4.2, Figure 5.4)
Indicative Linkages Between Mitigation Options and Sustainable 
        Development Using SDGs
(The Linkages Do Not Show Costs and Benefits)
    Mitigation options deployed in each sector can be associated with 
potential positive effects (synergies) or negative effects (trade-offs) 
with the Sustainable Development Goals (SDGs). The degree to which this 
potential is realized will depend on the selected portfolio of 
mitigation options, mitigation policy design, and local circumstances 
and context. Particularly in the energy-demand sector, the potential 
for synergies is larger than for trade-offs. The bars group 
individually assessed options by level of confidence and take into 
account the relative strength of the assessed mitigation-SDG 
connections.
Figure SPM.4


          Potential synergies and trade-offs between the sectoral 
        portfolio of climate change mitigation options and the 
        Sustainable Development Goals (SDGs). The SDGs serve as an 
        analytical framework for the assessment of the different 
        sustainable development dimensions, which extend beyond the 
        time frame of the 2030 SDG targets. The assessment is based on 
        literature on mitigation options that are considered relevant 
        for 1.5 C. The assessed strength of the SDG interactions is 
        based on the qualitative and quantitative assessment of 
        individual mitigation options listed in Table 5.2. For each 
        mitigation option, the strength of the SDG-connection as well 
        as the associated confidence of the underlying literature 
        (shades of green and red) was assessed. The strength of 
        positive connections (synergies) and negative connections 
        (trade-offs) across all individual options within a sector (see 
        Table 5.2) are aggregated into sectoral potentials for the 
        whole mitigation portfolio. The (white) areas outside the bars, 
        which indicate no interactions, have low confidence due to the 
        uncertainty and limited number of studies exploring indirect 
        effects. The strength of the connection considers only the 
        effect of mitigation and does not include benefits of avoided 
        impacts. SDG 13 (climate action) is not listed because 
        mitigation is being considered in terms of interactions with 
        SDGs and not vice versa. The bars denote the strength of the 
        connection, and do not consider the strength of the impact on 
        the SDGs. The energy demand sector comprises behavioural 
        responses, fuel switching and efficiency options in the 
        transport, industry and building sector as well as carbon 
        capture options in the industry sector. Options assessed in the 
        energy supply sector comprise biomass and non-biomass 
        renewables, nuclear, carbon capture and storage (CCS) with 
        bioenergy, and CCS with fossil fuels. Options in the land 
        sector comprise agricultural and forest options, sustainable 
        diets and reduced food waste, soil sequestration, livestock and 
        manure management, reduced deforestation, afforestation and 
        reforestation, and responsible sourcing. In addition to this 
        figure, options in the ocean sector are discussed in the 
        underlying report. (5.4, Table 5.2, Figure 5.2)
          Information about the net impacts of mitigation on 
        sustainable development in 1.5 C pathways is available only 
        for a limited number of SDGs and mitigation options. Only a 
        limited number of studies have assessed the benefits of avoided 
        climate change impacts of 1.5 C pathways for the SDGs, and the 
        co-effects of adaptation for mitigation and the SDGs. The 
        assessment of the indicative mitigation potentials in Figure 
        SPM.4 is a step further from AR5 towards a more comprehensive 
        and integrated assessment in the future.

    D.4.3  1.5 C and 2 C modelled pathways often rely on the 
deployment of large-scale land-related measures like afforestation and 
bioenergy supply, which, if poorly managed, can compete with food 
production and hence raise food security concerns (high confidence). 
The impacts of carbon dioxide removal (CDR) options on SDGs depend on 
the type of options and the scale of deployment (high confidence). If 
poorly implemented, CDR options such as BECCS and AFOLU options would 
lead to trade-offs. Context-relevant design and implementation requires 
considering people's needs, biodiversity, and other sustainable 
development dimensions (very high confidence). (Figure SPM.4) (5.4.1.3, 
Cross-Chapter Box 7 in Chapter 3)
    D.4.4  Mitigation consistent with 1.5 C pathways creates risks for 
sustainable development in regions with high dependency on fossil fuels 
for revenue and employment generation (high confidence). Policies that 
promote diversification of the economy and the energy sector can 
address the associated challenges (high confidence). (5.4.1.2, Box 5.2)
    D.4.5  Redistributive policies across sectors and populations that 
shield the poor and vulnerable can resolve trade-offs for a range of 
SDGs, particularly hunger, poverty and energy access. Investment needs 
for such complementary policies are only a small fraction of the 
overall mitigation investments in 1.5 C pathways. (high confidence) 
(2.4.3, 5.4.2, Figure 5.5)

    D.5  Limiting the risks from global warming of 1.5 C in the 
context of sustainable development and poverty eradication implies 
system transitions that can be enabled by an increase of adaptation and 
mitigation investments, policy instruments, the acceleration of 
technological innovation and behaviour changes (high confidence). (2.3, 
2.4, 2.5, 3.2, 4.2, 4.4, 4.5, 5.2, 5.5, 5.6)

    D.5.1  Directing finance towards investment in infrastructure for 
mitigation and adaptation could provide additional resources. This 
could involve the mobilization of private funds by institutional 
investors, asset managers and development or investment banks, as well 
as the provision of public funds. Government policies that lower the 
risk of low-emission and adaptation investments can facilitate the 
mobilization of private funds and enhance the effectiveness of other 
public policies. Studies indicate a number of challenges, including 
access to finance and mobilization of funds. (high confidence) (2.5.1, 
2.5.2, 4.4.5)
    D.5.2  Adaptation finance consistent with global warming of 1.5 C 
is difficult to quantify and compare with 2 C. Knowledge gaps include 
insufficient data to calculate specific climate resilience-enhancing 
investments from the provision of currently underinvested basic 
infrastructure. Estimates of the costs of adaptation might be lower at 
global warming of 1.5 C than for 2 C. Adaptation needs have typically 
been supported by public sector sources such as national and 
subnational government budgets, and in developing countries together 
with support from development assistance, multilateral development 
banks, and United Nations Framework Convention on Climate Change 
channels (medium confidence). More recently there is a growing 
understanding of the scale and increase in non-governmental 
organizations and private funding in some regions (medium confidence). 
Barriers include the scale of adaptation financing, limited capacity 
and access to adaptation finance (medium confidence). (4.4.5, 4.6)
    D.5.3  Global model pathways limiting global warming to 1.5 C are 
projected to involve the annual average investment needs in the energy 
system of around 2.4 trillion USD2010 between 2016 and 2035, 
representing about 2.5% of the world GDP (medium confidence). (4.4.5, 
Box 4.8)
    D.5.4  Policy tools can help mobilize incremental resources, 
including through shifting global investments and savings and through 
market and non-market based instruments as well as accompanying 
measures to secure the equity of the transition, acknowledging the 
challenges related with implementation, including those of energy 
costs, depreciation of assets and impacts on international competition, 
and utilizing the opportunities to maximize co-benefits (high 
confidence). (1.3.3, 2.3.4, 2.3.5, 2.5.1, 2.5.2, Cross-Chapter Box 8 in 
Chapter 3, Cross-Chapter Box 11 in Chapter 4, 4.4.5, 5.5.2)
    D.5.5  The systems transitions consistent with adapting to and 
limiting global warming to 1.5 C include the widespread adoption of 
new and possibly disruptive technologies and practices and enhanced 
climate-driven innovation. These imply enhanced technological 
innovation capabilities, including in industry and finance. Both 
national innovation policies and international cooperation can 
contribute to the development, commercialization and widespread 
adoption of mitigation and adaptation technologies. Innovation policies 
may be more effective when they combine public support for research and 
development with policy mixes that provide incentives for technology 
diffusion. (high confidence) (4.4.4, 4.4.5).
    D.5.6  Education, information, and community approaches, including 
those that are informed by indigenous knowledge and local knowledge, 
can accelerate the wide-scale behaviour changes consistent with 
adapting to and limiting global warming to 1.5 C. These approaches are 
more effective when combined with other policies and tailored to the 
motivations, capabilities and resources of specific actors and contexts 
(high confidence). Public acceptability can enable or inhibit the 
implementation of policies and measures to limit global warming to 1.5 
C and to adapt to the consequences. Public acceptability depends on 
the individual's evaluation of expected policy consequences, the 
perceived fairness of the distribution of these consequences, and 
perceived fairness of decision procedures (high confidence). (1.1, 1.5, 
4.3.5, 4.4.1, 4.4.3, Box 4.3, 5.5.3, 5.6.5)

    D.6  Sustainable development supports, and often enables, the 
fundamental societal and systems transitions and transformations that 
help limit global warming to 1.5 C. Such changes facilitate the 
pursuit of climate-resilient development pathways that achieve 
ambitious mitigation and adaptation in conjunction with poverty 
eradication and efforts to reduce inequalities (high confidence). (Box 
1.1, 1.4.3, Figure 5.1, 5.5.3, Box 5.3)

    D.6.1  Social justice and equity are core aspects of climate-
resilient development pathways that aim to limit global warming to 1.5 
C as they address challenges and inevitable trade-offs, widen 
opportunities, and ensure that options, visions, and values are 
deliberated, between and within countries and communities, without 
making the poor and disadvantaged worse off (high confidence). (5.5.2, 
5.5.3, Box 5.3, Figure 5.1, Figure 5.6, Cross-Chapter Boxes 12 and 13 
in Chapter 5)
    D.6.2  The potential for climate-resilient development pathways 
differs between and within regions and nations, due to different 
development contexts and systemic vulnerabilities (very high 
confidence). Efforts along such pathways to date have been limited 
(medium confidence) and enhanced efforts would involve strengthened and 
timely action from all countries and non-state actors (high 
confidence). (5.5.1, 5.5.3, Figure 5.1)
    D.6.3  Pathways that are consistent with sustainable development 
show fewer mitigation and adaptation challenges and are associated with 
lower mitigation costs. The large majority of modelling studies could 
not construct pathways characterized by lack of international 
cooperation, inequality and poverty that were able to limit global 
warming to 1.5 C. (high confidence) (2.3.1, 2.5.1, 2.5.3, 5.5.2)

    D.7 Strengthening the capacities for climate action of national and 
sub-national authorities, civil society, the private sector, indigenous 
peoples and local communities can support the implementation of 
ambitious actions implied by limiting global warming to 1.5 C (high 
confidence). International cooperation can provide an enabling 
environment for this to be achieved in all countries and for all 
people, in the context of sustainable development. International 
cooperation is a critical enabler for developing countries and 
vulnerable regions (high confidence). (1.4, 2.3, 2.5, 4.2, 4.4, 4.5, 
5.3, 5.4, 5.5, 5.6, 5, Box 4.1, Box 4.2, Box 4.7, Box 5.3, Cross-
Chapter Box 9 in Chapter 4, Cross-Chapter Box 13 in Chapter 5)

    D.7.1 Partnerships involving non-state public and private actors, 
institutional investors, the banking system, civil society and 
scientific institutions would facilitate actions and responses 
consistent with limiting global warming to 1.5 C (very high 
confidence). (1.4, 4.4.1, 4.2.2, 4.4.3, 4.4.5, 4.5.3, 5.4.1, 5.6.2, Box 
5.3).
    D.7.2 Cooperation on strengthened accountable multilevel governance 
that includes non-state actors such as industry, civil society and 
scientific institutions, coordinated sectoral and cross-sectoral 
policies at various governance levels, gender-sensitive policies, 
finance including innovative financing, and cooperation on technology 
development and transfer can ensure participation, transparency, 
capacity building and learning among different players (high 
confidence). (2.5.1, 2.5.2, 4.2.2, 4.4.1, 4.4.2, 4.4.3, 4.4.4, 4.4.5, 
4.5.3, Cross-Chapter Box 9 in Chapter 4, 5.3.1, 5.5.3, Cross-Chapter 
Box 13 in Chapter 5, 5.6.1, 5.6.3)
    D.7.3 International cooperation is a critical enabler for 
developing countries and vulnerable regions to strengthen their action 
for the implementation of 1.5 C-consistent climate responses, 
including through enhancing access to finance and technology and 
enhancing domestic capacities, taking into account national and local 
circumstances and needs (high confidence). (2.3.1, 2.5.1, 4.4.1, 4.4.2, 
4.4.4, 4.4.5, 5.4.1 5.5.3, 5.6.1, Box 4.1, Box 4.2, Box 4.7).
    D.7.4 Collective efforts at all levels, in ways that reflect 
different circumstances and capabilities, in the pursuit of limiting 
global warming to 1.5 C, taking into account equity as well as 
effectiveness, can facilitate strengthening the global response to 
climate change, achieving sustainable development and eradicating 
poverty (high confidence). (1.4.2, 2.3.1, 2.5.1, 2.5.2, 2.5.3, 4.2.2, 
4.4.1, 4.4.2, 4.4.3, 4.4.4, 4.4.5, 4.5.3, 5.3.1, 5.4.1, 5.5.3, 5.6.1, 
5.6.2, 5.6.3)

------------------------------------------------------------------------
 
-------------------------------------------------------------------------
         Box SPM.1: Core Concepts Central to this Special Report
 
    Global mean surface temperature (GMST): Estimated global average of
 near-surface air temperatures over land and sea ice, and sea surface
 temperatures over ice-free ocean regions, with changes normally
 expressed as departures from a value over a specified reference period.
 When estimating changes in GMST, near-surface air temperature over both
 land and oceans are also used.\19\ (1.2.1.1)
\19\ Past IPCC reports, reflecting the literature, have used a variety
 of approximately equivalent metrics of GMST change.
    Pre-industrial: The multi-century period prior to the onset of large-
 scale industrial activity around 1750. The reference period 1850-1900
 is used to approximate pre-industrial GMST. (1.2.1.2)
    Global warming: The estimated increase in GMST averaged over a 30
 year period, or the 30 year period centred on a particular year or
 decade, expressed relative to pre-industrial levels unless otherwise
 specified. For 30 year periods that span past and future years, the
 current multi-decadal warming trend is assumed to continue. (1.2.1)
    Net zero CO2 emissions: Net zero carbon dioxide (CO2) emissions are
 achieved when anthropogenic CO2 emissions are balanced globally by
 anthropogenic CO2 removals over a specified period.
    Carbon dioxide removal (CDR): Anthropogenic activities removing CO2
 from the atmosphere and durably storing it in geological, terrestrial,
 or ocean reservoirs, or in products. It includes existing and potential
 anthropogenic enhancement of biological or geochemical sinks and direct
 air capture and storage, but excludes natural CO2 uptake not directly
 caused by human activities.
    Total carbon budget: Estimated cumulative net global anthropogenic
 CO2 emissions from the pre-industrial period to the time that
 anthropogenic CO2 emissions reach net zero that would result, at some
 probability, in limiting global warming to a given level, accounting
 for the impact of other anthropogenic emissions. (2.2.2)
    Remaining carbon budget: Estimated cumulative net global
 anthropogenic CO2 emissions from a given start date to the time that
 anthropogenic CO2 emissions reach net zero that would result, at some
 probability, in limiting global warming to a given level, accounting
 for the impact of other anthropogenic emissions. (2.2.2)
    Temperature overshoot: The temporary exceedance of a specified level
 of global warming.
    Emission pathways: In this Summary for Policymakers, the modelled
 trajectories of global anthropogenic emissions over the 21st century
 are termed emission pathways. Emission pathways are classified by their
 temperature trajectory over the 21st century: pathways giving at least
 50% probability based on current knowledge of limiting global warming
 to below 1.5 C are classified as `no overshoot'; those limiting warming
 to below 1.6 C and returning to 1.5 C by 2100 are classified as `1.5 C
 limited-overshoot'; while those exceeding 1.6 C but still returning to
 1.5 C by 2100 are classified as `higher-overshoot'.
    Impacts: Effects of climate change on human and natural systems.
 Impacts can have beneficial or adverse outcomes for livelihoods, health
 and well-being, ecosystems and species, services, infrastructure, and
 economic, social and cultural assets.
    Risk: The potential for adverse consequences from a climate-related
 hazard for human and natural systems, resulting from the interactions
 between the hazard and the vulnerability and exposure of the affected
 system. Risk integrates the likelihood of exposure to a hazard and the
 magnitude of its impact. Risk also can describe the potential for
 adverse consequences of adaptation or mitigation responses to climate
 change.
    Climate-resilient development pathways (CRDPs): Trajectories that
 strengthen sustainable development at multiple scales and efforts to
 eradicate poverty through equitable societal and systems transitions
 and transformations while reducing the threat of climate change through
 ambitious mitigation, adaptation and climate resilience.
------------------------------------------------------------------------

                              attachment 2


[https://www.instituteforenergyresearch.org/climate-change/global-
carbon-dioxide-emissions-fell-7-percent-in-2020/]
Institute for Energy Research
Commentary (https://www.instituteforenergyresearch.org/type/commentary/
)
Global Carbon Dioxide Emissions Fell 7 Percent in 2020
By IER (https://www.instituteforenergyresearch.org/about/ier-site-
manager/articles)

January 26, 2021

    Due mainly to the lockdowns from the coronavirus pandemic, carbon 
dioxide emissions are estimated to have declined by 7 percent globally 
\1\ in 2020, while U.S. carbon dioxide emissions are estimated to have 
declined more--by 10.3 percent \2\--to the lowest level since 1990, 3 
decades ago. Despite China's carbon dioxide emissions falling during 
the first 4 months of 2020, they are expected to have increased as the 
country had an increase in its GDP of 2.3 percent \3\ in 2020, 
according to its National Bureau of Statistics--the only major economy 
to have its economy recover from the coronavirus pandemic. The 
International Energy Agency's Birol \4\ agrees with this expected 
increase in China's carbon dioxide emissions in 2020.
---------------------------------------------------------------------------
    \1\ https://www.carbonbrief.org/global-carbon-project-coronavirus-
causes-record-fall-in-fossil-fuel-emissions-in-2020.
    \2\ https://qz.com/1956081/the-pandemic-took-us-emissions-to-their-
lowest-level-in-decades/.
    \3\ https://www.nytimes.com/2021/01/17/business/china-economy-
gdp.html.
    \4\ https://www.reuters.com/article/us-china-emissions/chinas-co2-
emissions-will-be-higher-in-2020-than-in-2019-says-ieas-birol-
idUSKBN28510F.
---------------------------------------------------------------------------
The World
    The seven percent \5\ annual decline in global carbon dioxide 
emissions is the largest absolute drop in emissions ever recorded, and 
the largest relative fall since the second world war. Carbon dioxide 
emissions have fallen in most of the world's biggest emitters, the 
United States, the European Union, and India. This year has also seen 
the first fall in global emissions since a 1.3 percent drop in 2009,\6\ 
which was driven by the global financial crisis that started in 2008.
---------------------------------------------------------------------------
    \5\ https://www.carbonbrief.org/global-carbon-project-coronavirus-
causes-record-fall-in-fossil-fuel-emissions-in-2020.
    \6\ https://www.nature.com/articles/ngeo1022.
---------------------------------------------------------------------------
Global CO2 Emissions from Fossil Fuels by Region, 1959-2020


          Source: Carbon Brief.\7\
---------------------------------------------------------------------------
    \7\ https://www.carbonbrief.org/global-carbon-project-coronavirus-
causes-record-fall-in-fossil-fuel-emissions-in-2020.

    The decline in carbon dioxide emissions in the EU27 \8\ is expected 
to be 11 percent in 2020. Carbon dioxide emissions from oil, natural 
gas and cement are estimated to drop by 12 percent, three percent, and 
five percent, respectively. Consumption of both oil and natural gas, 
however, have been rebounding in recent years.
---------------------------------------------------------------------------
    \8\ https://europa.eu/european-union/about-eu/countries_en.
---------------------------------------------------------------------------
    A 13-percent decline in emissions is predicted in the UK this year 
as a result of the extensive lockdown measures introduced in March, 
plus the second wave of the pandemic. The only country that is expected 
to have a larger drop in carbon dioxide emissions is France--by 15 
percent.
    Carbon dioxide emissions in India \9\--the world's third largest 
emitter--increased by just one percent in 2019 before the pandemic hit. 
This was a result of economic turmoil and strong hydropower generation. 
Despite a trend of growing emissions in India from oil and coal over 
the past decade--alongside moderate growth in natural gas and cement--
the pandemic is expected to reduce carbon dioxide emissions by seven 
percent, ten percent, 2 percent and 15 percent, respectively, in 2020 
in these four areas. 2020 is the first year in 4 decades in which 
emissions in India are expected to decline--a nine-percent overall 
reduction.
---------------------------------------------------------------------------
    \9\ https://www.carbonbrief.org/the-carbon-brief-profile-india.
---------------------------------------------------------------------------
United States
    The biggest drop in U.S. carbon dioxide emissions was in the 
transportation sector. For the first 9 months of 2020, carbon dioxide 
emissions in the transportation sector dropped 15 percent \10\--similar 
to air and road passenger travel miles, which fell 15 percent below 
2019 levels for the first 10 months of 2020. The steep drop-off \11\ in 
air travel was the biggest contributor, with jet fuel consumption 
falling 68 percent \12\ at the peak of lockdowns in April and May. 
Gasoline (primarily from passenger vehicles) was down 40 percent in 
April and May and diesel (used in shipping and trucking) was down 18 
percent. Jet fuel demand recovered somewhat bouncing back to around 35 
percent below 2019 levels in December based on preliminary data. Diesel 
spurred by holiday deliveries returned to near 2019 levels in December.
---------------------------------------------------------------------------
    \10\ https://www.eia.gov/totalenergy/data/monthly/pdf/sec11_8.pdf.
    \11\ https://qz.com/1952203/are-people-traveling-by-air-again-
despite-covid-19/.
    \12\ https://rhg.com/research/preliminary-us-emissions-2020/.
---------------------------------------------------------------------------
    Passenger travel bounced back quickly after travel restrictions 
were lifted in May and June in most regions. The first round of 
shelter-in-place orders led to a sharp decline in passenger vehicle 
travel (measured by vehicle-miles-traveled), dropping 40 percent \13\ 
at its peak in April. But travel recovered quickly by June (down only 
13 percent) with a more gradual recovery through October (the last 
month of available data).
---------------------------------------------------------------------------
    \13\ https://rhg.com/research/preliminary-us-emissions-2020/.
---------------------------------------------------------------------------
Figure 3
Change in Monthly Passenger Vehicle Miles Traveled, 2020 vs. 2019
Percent Change from 2019 Levels


          Source: Rhodium Group.\14\
---------------------------------------------------------------------------
    \14\ https://rhg.com/research/preliminary-us-emissions-2020/.

    In the U.S. electric power sector, carbon dioxide emissions dropped 
12 percent \15\ for the first 9 months of the year. The pandemic 
hastened current trends, with coal use declining and natural gas and 
renewable energy increasing. Those trends are expected to continue with 
solar and wind power accounting for 70 percent,\16\ 39 percent and 31 
percent, respectively, of planned new power installations for 2021 and 
natural gas accounting for 16 percent, according to the Energy 
Information Administration (EIA). The new nuclear reactor at the Vogtle 
power plant in Georgia will account for three percent of the new 
capacity and batteries for 11 percent. Total new capacity announced by 
utilities for 2021 is almost 40 gigawatts.
---------------------------------------------------------------------------
    \15\ https://www.eia.gov/totalenergy/data/monthly/pdf/sec11_9.pdf.
    \16\ https://www.eia.gov/todayinenergy/
detail.php?id=46416&src=email.
---------------------------------------------------------------------------
    Taxpayers will pay subsidies for the solar, wind, and battery 
capacity coming on line this year. According to EIA, the average 
capital cost for solar PV is $1,331 per kilowatt.\17\ With 15.4 
gigawatts of announced capacity, and an investment tax credit of 26 
percent, taxpayers will pay $5.3 billion for the solar capacity subsidy 
in 2021. Battery technology also gets the same subsidy. With 4.3 
gigawatts of announced battery capacity at an average cost of $1,383 
per kilowatt \18\ according to EIA, taxpayers will pay $1.55 billion in 
subsidies. Wind also gets a tax subsidy; it is on the amount of 
electricity production from the wind turbines and lasts for the first 
10 years of their operation.
---------------------------------------------------------------------------
    \17\ https://www.eia.gov/outlooks/aeo/assumptions/pdf/
table_8.2.pdf.
    \18\ https://www.eia.gov/outlooks/aeo/assumptions/pdf/
table_8.2.pdf.
---------------------------------------------------------------------------
Planned U.S. Utility-Scale Electricity Generating Capacity Additions 
        (2021)
gigawatts (GW)


          Source: Energy Information Administration.\19\
---------------------------------------------------------------------------
    \19\ https://www.eia.gov/todayinenergy/detail.php?.
---------------------------------------------------------------------------
China
    China's economy shrank 6.8 percent in the January-March \20\ period 
compared with 2019--the first contraction in nearly half a century as 
travel and business was nearly halted. Since then, the economy has 
improved steadily, finishing the year with growth of 6.5 percent in the 
last 3 months compared to the same period in 2019. Factories across 
China are filling overseas orders and cranes are busy at construction 
sites--this boom is expected to drive the economy in 2021.
---------------------------------------------------------------------------
    \20\ https://www.nytimes.com/2020/04/16/business/china-coronavirus-
economy.html.
---------------------------------------------------------------------------
    When Wuhan was still under lockdown, China moved to get 
manufacturing up and running in other areas. The government provided 
long-haul buses to get workers from their home villages to factories 
after the Chinese New Year. State-owned banks extended special loans to 
factories, while many government agencies gave partial refunds of 
business taxes that had been paid before the pandemic.
    Beijing also ramped up its infrastructure spending. With every 
major city in China already connected with high-speed rail lines, new 
lines were added to smaller cities and new expressways crisscrossed 
remote western provinces. Construction companies turned on floodlights 
at many sites so that work could continue around the clock.
    Despite the trade war and tariffs, American and European companies 
turned to China for parts and goods when factories elsewhere struggled 
to meet demand. Factories within China turned to nearby suppliers to 
replace imports as transoceanic supply lines became less dependable.
    Exports and infrastructure fueled much of the growth over the past 
year. China's exports grew 18.1 percent in December \21\ compared with 
the same month a year earlier, and were up 21.1 percent in November. 
Fixed-asset investment in everything from high-speed rail lines to new 
apartment buildings increased 2.9 percent last year.
---------------------------------------------------------------------------
    \21\ https://www.nytimes.com/2021/01/17/business/china-economy-
gdp.html.
---------------------------------------------------------------------------
    The Chinese Academy of Social Sciences predicts that the country's 
economy would expand 7.8 percent in 2021.\22\ If it does, it would be 
China's strongest performance in 9 years. With that expansion, the 
world can expect increased carbon dioxide emissions as China uses 
mainly fossil fuels to fuel its economy \23\ and is increasing their 
use at a breakneck speed.
---------------------------------------------------------------------------
    \22\ https://www.nytimes.com/2021/01/17/business/china-economy-
gdp.html.
    \23\ https://www.instituteforenergyresearch.org/international-
issues/chinas-economy-is-based-on-fossil-fuels/.
---------------------------------------------------------------------------
    Birol, the head of the International Energy Agency, expects \24\ 
China's oil demand to be slightly higher in 2020 than it was in 2019, 
and its natural gas demand to be much higher in 2020 compared to 2019. 
China has been and is being hit with an extreme cold spell \25\ that 
will increase its heating fuel demand.
---------------------------------------------------------------------------
    \24\ https://www.reuters.com/article/us-china-emissions/chinas-co2-
emissions-will-be-higher-in-2020-than-in-2019-says-ieas-birol-
idUSKBN28510F.
    \25\ https://www.instituteforenergyresearch.org/.
---------------------------------------------------------------------------
Conclusion
    Most countries are expected to lower their carbon dioxide emissions 
in 2020 due to lockdowns caused by the coronavirus pandemic. The only 
exception is China, whose economy grew by 2.3 percent in 2020 and who 
is taking advantage of the downturn in manufacturing in other 
countries, increasing its exports tremendously by the end of 2020. It 
appears China is very serious about spurring its economic growth for 
its citizens' welfare and is using more energy--fossil energy--to do 
so.
                              attachment 3
[https://www.nationalgeographic.com/science/article/plunge-in-carbon-
emissions-lockdowns-will-not-slow-climate-change]


National Geographic


          Power plants, industry, and other carbon-emitting activities 
        kept on belching out greenhouse gases during the coronavirus-
        related lockdowns.
          Photograph By Bartek Sadowski, Bloomberg/Getty Images.
Plunge in carbon emissions from lockdowns will not slow climate change
          Emissions may be down, but carbon dioxide still piles up 
        relentlessly in the atmosphere. It's more important than ever 
        to find climate change solutions, experts say.

By Alejandra Borunda

Published May 20, 2020

    In May, the concentration of carbon dioxide in the atmosphere crept 
up to about 418 parts per million.\1\ It was the highest ever recorded 
in human history and likely higher than at any point in the last 3 
million years.
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    \1\ https://www.esrl.noaa.gov/gmd/ccgg/trends/monthly.html.
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    That record was broken in the midst of the coronavirus pandemic, 
even though the health crisis has driven one of the largest, most 
dramatic drops in CO2 emissions ever recorded. During the 
peak of the global confinements in the first quarter of the year, daily 
emissions were about 17 percent below last year's, according to 
research published this week in Nature Climate Change.\2\
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    \2\ https://www.nature.com/articles/s41558-020-0797-x.
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    But even such big drops in carbon dioxide emissions will have 
little impact on overall CO2 concentration \3\ in the 
atmosphere, says Richard Betts \4\--a scientist at the U.K.'s Met 
Office--and that's what matters most for climate change.
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    \3\ https://www.nationalgeographic.com/environment/article/global-
warming-causes.
    \4\ https://www.metoffice.gov.uk/research/people/richard-betts.
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Percentage change in global daily fossil CO2 emissions, 
        since Jan. 4, 2020
        
        
          Ng Staff.
          Source: Le Quere, et al. Nature Climate Change (2020); Global 
        Carbon Project.

    The pandemic has disrupted life around the world, and stay-at-home 
orders have kept large swaths of the world at home for months now. But 
the disruption only results in a tiny drop in the overall concentration 
of CO2 in the atmosphere because of how long the gas 
effectively lingers.
    So that record concentration of 418 parts per million? That would 
have been just 0.4 parts per million higher without the virus-driven 
emissions drop, according to an analysis posted on climate science and 
policy website CarbonBrief \5\ earlier in May.
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    \5\ https://www.carbonbrief.org/analysis-what-impact-will-the-
coronavirus-pandemic-have-on-atmospheric-co2.
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    Still, for energy and climate expert Constantine Samaras,\6\ the 
message is clear: Just because this devasting pandemic has only a small 
impact on today's CO2 levels doesn't mean the climate crisis 
is lost.
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    \6\ https://www.cmu.edu/cee/people/faculty/samaras.html.
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    ``A pandemic is the worst possible way to reduce emissions. There's 
nothing to celebrate here,'' says Samaras, of Carnegie Mellon 
University. ``We have to recognize that, and to recognize that 
technological, behavioral, and structural change is the best and only 
way to reduce emissions.''
What did we see with CO2 emissions vs. concentrations?
    During this unprecedented, deadly global event, millions of people 
who could stay at home did just that. Cars sat in driveways. Air travel 
ground to a halt. Manufacturing plants slowed or stopped. Public 
buildings shut their doors. Even construction slowed down. Nearly every 
sector of the energy-using economy reacted to the shock in one way or 
another.
    The result was one of the biggest single drops in modern history in 
the amount of carbon dioxide humans emit.
    Over the first few months of 2020, global daily CO2 
emissions averaged about 17 percent lower than in 2019. At the moments 
of the most restrictive and extensive lockdowns, emissions in some 
countries hovered nearly 30 percent below last year's averages, says 
Glen Peters,\7\ one of the authors of the Nature Climate Change 
analysis and a climate scientist at Norway's Center for International 
Climate Research.
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    \7\ https://cicero.oslo.no/no/rapid-response-glen-peters.
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    China's emissions decreased by about a quarter in February. Other 
countries saw drops of a few percent in March and April, a team led by 
Tsinghua University's Zhu Liu \8\ found in a separate analysis.\9\ The 
effects, in some ways, are big--but in other ways, not big enough, he 
says.
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    \8\ https://scholar.harvard.edu/zhu/home.
    \9\ https://arxiv.org/pdf/2004.13614.pdf.
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    ``Only when we would reduce our emissions even more than this for 
longer would we be able to see the decline in concentrations in the 
atmosphere,'' he says. ``We would probably need, like, a 20 percent 
reduction for the whole year--so every month, for the whole world, like 
April. But the world cannot suffer so long a lockdown.''
    The International Energy Agency estimates that by the end of 2020, 
global emissions will decline by about eight percent \10\ compared to 
last year. That would work out to about 2.6 billion tons of carbon not 
added to the atmosphere. The Nature Climate Change team estimates that 
drop to be somewhere between four to seven percent, depending on the 
way lockdowns develop over the rest of the year. If people are driven 
back into their homes by rising COVID-19 infection rates, emissions 
could fall even more.
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    \10\ https://www.iea.org/news/global-energy-demand-to-plunge-this-
year-as-a-result-of-the-biggest-shock-since-the-second-world-war.
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    But that doesn't mean the carbon dioxide problem is solved, or even 
that there will be much positive effect on skies overfull with 
CO2.
    ``Climate change is a cumulative problem,'' says Peters. ``It's not 
like other pollution, where someone is putting something in the river 
and then they stop putting it in the river and [the] problem is solved. 
It's all our emissions in the past that matter.''
    Think of the atmosphere as a bathtub. Human-driven CO2 
emissions are like the water coming out of the tap. The ocean and land, 
which absorb or use up some of that CO2, are the drain--but 
even when they're wide open, they can only let out half the water that 
comes in.
    When a momentous event like this pandemic happens to push 
CO2 emissions down, it's as if the bath's tap has been shut 
by 17 percent. But over 80 percent of the water is still gushing into 
the tub, so the water level in the tub will still rise. It might not 
fill quite as quickly as it did before, but it's definitely not 
draining completely.
    In short, even though emissions have dropped, CO2 is 
still going into the atmosphere and it will still accumulate there, 
just as it has since humans started burning vast amounts of fossil 
fuels.
    ``We treat the atmosphere like this big waste dump,'' says Ralph 
Keeling,\11\ a scientist at the Scripps Institution of Oceanography 
whose lab runs the Mauna Loa long-term monitoring project of 
atmospheric CO2.\12\ ``But when you throw something in the 
trash, it's still in the landfill. It's still out there. We can't just 
sweep it away.''
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    \11\ https://rkeeling.scrippsprofiles.ucsd.edu/.
    \12\ https://www.esrl.noaa.gov/gmd/obop/mlo/.
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What does this emissions drop mean for for climate?
    Scientists have a pretty good idea of how much more atmospheric 
CO2 will accumulate each year: about half as much as we pump 
up there (the other half gets absorbed by plants and the oceans). Each 
year, the average concentration gets higher. In 2018, for example, 
concentrations rose by 2.5 parts per million,\13\ to an average of 
407.4; 2019 averages have not yet been released, but a similar value is 
expected.
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    \13\ https://www.ametsoc.org/ams/index.cfm/publications/bulletin-
of-the-american-meteorological-society-bams/state-of-the-climate/.
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    On top of this rising pattern--which depends primarily on how much 
humans emit--CO2 concentrations go up and down during the 
seasons. They're highest in late spring each year, as plants around the 
Northern Hemisphere wake up from the winter and gobble up the carbon 
food, and lowest in early fall, as plants slow down for the coming 
winter (the Northern Hemisphere has so much more land and plants than 
the southern that it dominates the pattern).
    Betts and his colleagues run a model that makes these predictions 
for the coming year. Their forecasts are usually remarkably 
accurate.\14\ As soon as it became clear that coronavirus would 
suppress emissions this year, they realized that they could figure out 
exactly how much the drop would affect the overall concentrations of 
CO2 in the atmosphere.
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    \14\ https://royalsocietypublishing.org/doi/10.1098/rstb.2017.0301.
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    By the beginning of the pandemic, Betts's team had already 
predicted what atmospheric CO2 was supposed to do in 2020. 
They forecast that in May, at the peak of the gas's annual seasonal 
cycle, its concentration would probably hover around 417 ppm (and sure 
enough, in early May the station saw a concentration of just over 418 
parts per million.) The team also expected that at its seasonal low in 
September, it would be around 410 parts per million. So the final 
prediction, for the average over the course of the year: 414 parts per 
million. That's barely different than what the team expected without 
the coronavirus-related impacts.
    ``The message of all that is that there's a limit of what you can 
do with individual actions,'' says Betts--actions such as driving or 
flying less. ``We've probably done as much as we can, personally, to 
reduce our own emissions during this devastating time.''
    So, he says, ``it's not about going back to the way things were, 
but to a better way.''
We're still emitting way too much CO2
    What Betts showed was the dark side of the emissions problem. Even 
with all this economic upheaval and the emotional toll of isolating, 
our emissions have dropped only 17 percent in the short term and will 
likely drop by less than ten percent for the year. The effects of those 
declines on the overall greenhouse gas problem are infinitesimal.
    Framed another way: We're still spitting out more than 80 percent 
as much CO2 as normal, even when life feels devastatingly 
different. Staying home, it is abundantly clear now, is far from enough 
to solve the climate crisis.
    ``From humanity's perspective, the COVID-19 pandemic is the largest 
event many of us have ever experienced. It affects literally everyone 
on the planet,'' says Anna Michalak,\15\ a scientist at Stanford's 
Carnegie Institution for Science.
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    \15\ https://dge.carnegiescience.edu/people/michalak.
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    ``In a way, it's hard to mentally reconcile that with just a small 
difference in emissions; it seems almost dismissive. But what's 
important to remember is that this shows how the use of carbon as a 
fuel source is so deeply embedded in every aspect of how humanity runs 
itself, so the emissions keep happening,'' she says.
    The IPCC has warned that global temperature rises should be limited 
to 2.7 F (1.5 C) \16\ beyond pre-industrial levels in order to keep 
the worst,\17\ most devastating \18\ effects of climate change from 
battering human societies. To hit that goal, overall human-caused 
greenhouse gas emissions need to start dropping by about 7.6 percent 
each year \19\ from now until 2030 (and beyond). Eventually, of course, 
they need to get to zero.
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    \16\ https://www.nationalgeographic.com/environment/article/ipcc-
report-climate-change-impacts-forests-emissions.
    \17\ https://www.nationalgeographic.com/environment/article/
climate-change-model-warns-of-difficult-future.
    \18\ https://www.nationalgeographic.com/environment/article/ipcc-
un-food-security.
    \19\ https://wedocs.unep.org/bitstream/handle/20.500.11822/30797/
EGR2019.pdf?sequence=
1&isAllowed=y.
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    This year's emissions drop is right around eight percent. Samaras 
says that in no way represents what a concerted global effort to 
actually hit that goal would do. But it also shouldn't be taken as an 
indication that efforts would be futile.
    ``The message shouldn't be: It's too hard,'' he says. ``The message 
should be: We have to work hard to find a way to do this well.''
Where is all the CO2 still coming from?
    The Nature Climate Change team split the CO2 sources 
into six categories and looked at how much each changed between January 
and April, while countries rolled in and out of confinement.
    The biggest change in activity was in aviation; it dropped by an 
average of 75 percent by early April. But planes only make up about 
three percent of the CO2 emissions problem, so even that 
giant decrease has had only a small effect on the gushing of the 
CO2 ``tap.''
    The other huge change was in surface transport such as cars and 
trucks, where daily activity sank an average of 50 percent. That change 
translated into a big effect on emissions, because driving makes up a 
bigger piece of the normal CO2-waste pie. In the 4 months 
that people drove less, about 6 megatons of CO2 didn't go 
into the atmosphere each day, equal to about 1.2 million American cars' 
yearly mileage.
    About 45 percent of the world's CO2 waste generally 
comes from making heat and power. During the crisis, people needed 
those almost as much as ever. Emissions from power use dropped by about 
15 percent--which translated into about 3.3 megatons of CO2 
not added to the atmosphere each day.
    All in all, the reduction in daily emissions got us, as a planet, 
back down to the levels we were at in 2006. The IPCC's 2.7 F goals 
suggest that we need to get back to 1990s emissions levels within about 
a decade.
    ``This pandemic--it's tragic,'' says Michalak. ``It's not anyone's 
preferred way to get [CO2 reductions]. But what this 
experience does show is when humanity is united around a goal, big 
changes can happen on short time scales.''

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