[Senate Hearing 109-1111]
[From the U.S. Government Publishing Office]

                                                       S. Hrg. 109-1111

                       PROJECTED AND PAST EFFECTS
                     OF CLIMATE CHANGE: A FOCUS ON



                               before the

                              AND IMPACTS

                                 OF THE

                         COMMITTEE ON COMMERCE,
                      SCIENCE, AND TRANSPORTATION
                          UNITED STATES SENATE

                       ONE HUNDRED NINTH CONGRESS

                             SECOND SESSION


                             APRIL 26, 2006


    Printed for the use of the Committee on Commerce, Science, and 

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                       ONE HUNDRED NINTH CONGRESS

                             SECOND SESSION

                     TED STEVENS, Alaska, Chairman
JOHN McCAIN, Arizona                 DANIEL K. INOUYE, Hawaii, Co-
CONRAD BURNS, Montana                    Chairman
TRENT LOTT, Mississippi              JOHN D. ROCKEFELLER IV, West 
KAY BAILEY HUTCHISON, Texas              Virginia
OLYMPIA J. SNOWE, Maine              JOHN F. KERRY, Massachusetts
GORDON H. SMITH, Oregon              BYRON L. DORGAN, North Dakota
JOHN ENSIGN, Nevada                  BARBARA BOXER, California
GEORGE ALLEN, Virginia               BILL NELSON, Florida
JOHN E. SUNUNU, New Hampshire        MARIA CANTWELL, Washington
JIM DeMINT, South Carolina           FRANK R. LAUTENBERG, New Jersey
DAVID VITTER, Louisiana              E. BENJAMIN NELSON, Nebraska
                                     MARK PRYOR, Arkansas
             Lisa J. Sutherland, Republican Staff Director
        Christine Drager Kurth, Republican Deputy Staff Director
             Kenneth R. Nahigian, Republican Chief Counsel
   Margaret L. Cummisky, Democratic Staff Director and Chief Counsel
   Samuel E. Whitehorn, Democratic Deputy Staff Director and General 
             Lila Harper Helms, Democratic Policy Director


                   DAVID VITTER, Louisiana, Chairman
TED STEVENS, Alaska                  FRANK R. LAUTENBERG, New Jersey, 
JOHN McCAIN, Arizona                     Ranking
OLYMPIA J. SNOWE, Maine              JOHN F. KERRY, Massachusetts

                            C O N T E N T S

Hearing held on April 26, 2006...................................     1
Statement of Senator Lautenberg..................................     3
Statement of Senator Stevens.....................................     2
Statement of Senator Vitter......................................     1


Akasofu, Dr. Syun-Ichi, Director, International Arctic Research 
  Center, University of Alaska Fairbanks.........................    39
    Prepared statement...........................................    40
Armstrong, Dr. Thomas R., Program Coordinator, Earth Surface 
  Dynamics Program, U.S. Geological Survey, Department of the 
  Interior.......................................................    20
    Prepared statement...........................................    22
Corell, Dr. Robert W., Senior Fellow, American Meteorological 
  Society; Affiliate, Washington Advisory Group; Chair, Arctic 
  Climate Impact Assessment......................................    47
    Prepared statement...........................................    50
Murawski, Ph.D., Steven A., Director of Scientific Programs/Chief 
  Science Advisor, National Marine Fisheries Service and 
  Ecosystem Goal Team Lead, National Oceanic and Atmospheric 
  Administration, Department of Commerce.........................     5
    Prepared statement...........................................     8
Reiter, Paul, Chief, Insects and Infectious Disease Unit; 
  Professor, Institut Pasteur....................................    71
    Prepared statement...........................................    73


Inouye, Hon. Daniel K., U.S. Senator from Hawaii, prepared 
  statement......................................................    89
Response to written questions submitted by Hon. Daniel K. Inouye 
  to Steven A. Murawski, Ph.D....................................    89
Response to written questions submitted by Hon. Frank R. 
  Lautenberg to:
    Dr. Syun-Ichi Akasofu........................................    98
    Steven A. Murawski, Ph.D.....................................    92

                       PROJECTED AND PAST EFFECTS
                     OF CLIMATE CHANGE: A FOCUS ON


                       WEDNESDAY, APRIL 26, 2006

                               U.S. Senate,
         Subcommittee on Global Climate Change and Impacts,
        Committee on Commerce, Science, and Transportation,
                                                    Washington, DC.
    The Subcommittee met, pursuant to notice, at 2:30 p.m. in 
room SD-562, Dirksen Senate Office Building, Hon. David Vitter, 

Chairman of the Subcommittee, presiding.

                  U.S. SENATOR FROM LOUISIANA

    Senator Vitter. This is the Subcommittee on Global Climate 
Change and Impacts of the Senate Commerce Committee, and our 
hearing today is on the projected and past effects of climate 
change, a focus on marine and terrestrial systems.
    Thank you all for being here. Today, we'll have a hearing 
on just that, the projected and past effects of climate change, 
with a particular focus on marine and land systems.
    It's clear that we are experiencing a warming trend. Many 
scientists say that temperatures we're seeing right now are not 
outside of historical ranges experienced on Earth; however, if 
temperatures continue to increase, we would be entering 
uncharted territory.
    Similarly, carbon dioxide concentrations in both our 
atmosphere and oceans are at levels never seen before. And 
while I enjoy forging new frontiers in many areas, this is not 
one any of us are excited to do.
    So, this hearing will concentrate on the realized 
historical and also future predicted impacts of climate change, 
specifically on the health of our oceans, humans, plants and 
animals, and other Earth systems.
    I'm very interested in examining, through this hearing, how 
much we can ascertain from historical climatic variation and 
apply this knowledge to current and future changes and 
conditions. For once, we're not here to argue about the causes 
of observed warming trends or whether mandatory or market-based 
incentives are the best solution to reducing greenhouse gas 
emissions. Rather, we all agree that clearly understanding the 
potential changes we face in our environment as a result of 
this current cycle is an important task.
    We've seen predictions that our seas will rise 30 feet, and 
other extraordinary estimates. Certainly, I hope those won't 
come true. If so, I imagine many of us will have to migrate to 
higher ground in Alaska, maybe even run against Ted Stevens. I 
don't look forward to that. I know what the outcome would be.
    In addition, the State of Louisiana has many low-lying 
coastal areas, as many in the Nation discovered after 
Hurricanes Katrina and Rita. The impressive work of LSU's 
Spatial Reference Center and the Center for GeoInformatics and 
the National Geodetic Survey have been very helpful in 
providing data we need in our part of the world, in terms of 
that situation in south Louisiana.
    So, we're facing many of these challenges at home. The land 
is sinking, levees are settling. We lose a football field of 
wetlands every 38 minutes. The Corps of Engineers is currently 
rebuilding our flood and hurricane protection systems without 
the design flaws of the past, but the issue of net sea-level 
rise is very important as we do that work, as well.
    Sea-level rise is just one component of the hearing today. 
The State of Louisiana is the largest producer of fisheries in 
the lower 48, and we need to gain a better understanding of how 
ocean changes could affect our fishermen and the growing demand 
for wild, domestic seafood.
    We'll also discuss other potential changes related to our 
polar and temperate glaciers, impacts on plants and animals, 
and, of course, the important issue of human health.
    I want to commend to my colleagues that we share the common 
goal of ensuring the best science and understanding of all of 
these potential future changes.
    As CEQ Chair Jim Connaughton testified at our last hearing, 
the U.S. is dedicating more resources to climate change science 
and technology than any other country, probably more than all 
other countries combined. We're seeing reductions in our 
emissions intensity now, and we must continue these efforts to 
meet national goals.
    In closing, I want to point out that we have witnesses that 
have traveled from Paris and Fairbanks to be with us today. 
And, while I appreciate all of you being here today, I want to 
extend a special thanks to Dr. Akasofu and Dr. Reiter for your 
efforts to be with us. And I look forward to everyone's 
    With that, we'll turn to the full Committee Chairman, 
Senator Stevens.

                    U.S. SENATOR FROM ALASKA

    The Chairman. Well, thank you very much, Senator Vitter, 
for conducting this hearing.
    At my suggestion, the full Committee created this new 
subcommittee to deal specifically with global climate change. 
And it's imperative that the decisionmakers in all our 
governments and industry have the best possible science to rely 
upon as we deal with the problems of global climate change.
    There is a great deal of uncertainty, as we all know, about 
the causes, but I don't think there's much, really, doubt that 
there are changes taking place, and in particular in Alaska and 
the Arctic. We have faced severe coastal erosion. We have faced 
polar glacier recession. We have had melting permafrost, 
migration of species, all sorts of problems regarding our 
forests, and increased risks of fires in Alaska. And our native 
villages have faced the problems of changes that are much 
greater than taking place anywhere else in the United States.
    We think that if we can understand and, really, watch 
what's going on in Alaska, that the rest of the country will 
learn from it. And I hope that this hearing will demonstrate 
    It is critical that we examine the problems of Alaska on 
the basis of sound science, and that's why I'm delighted that 
there are some familiar faces here today, for me. Dr. Bob 
Corell is Chair of the Arctic Climate Impact Assessment Team, 
and he's done a great deal of research. We'll learn more about 
that today. And my long-time friend and advisor, Dr. Syun 
Akasofu, who directs our International Arctic Research Center 
in Fairbanks. He has, as you said, flown a long way, and I 
think it's about the third time he's come down this year, at 
our request, to appear in various ways. He earned his doctorate 
in studying the composition of the aurora borealis--``northern 
lights,'' to most people--and he's devoted 20 years now to 
studying the climate of our area. So, I know of no one in the 
world that I would rely on more than Syun, who has, I think, 
demonstrated his objectivity and his honesty, in terms of 
dealing with these issues.
    So, again, I think that this is a very timely hearing. I 
wish the whole Senate was here to listen to these people, 
because these are the people that can give us the information 
now that we ought to listen to as we try to consider some of 
the suggestions that are being made concerning what the Federal 
Government could do--should do concerning global climate 
    Thank you very much.
    Senator Vitter. Thank you, Mr. Chairman.
    And we also have our Ranking Member, Senator Lautenberg.
    Thank you for being here, Senator. And if you have any 
opening statement, please feel free to make it.

                  U.S. SENATOR FROM NEW JERSEY

    Senator Lautenberg. Thanks, Mr. Chairman. I'm pleased to be 
here. And I'm pleased, particularly, that our Chairman of the 
whole Committee is with us.
    We have, Mr. Chairman, a vote that's started. And I don't 
know what you'd like to schedule. Should we--I'll make my 
statement, and then shall we adjourn for a few minutes to carry 
on with our business? I'm----
    Senator Vitter. Why don't we do just that, if it's----
    Senator Lautenberg. Yes.
    Senator Vitter.--agreeable to you.
    Senator Lautenberg. That'd be perfect.
    And one of the reasons that I'm pleased to share this 
platform today with each of you is the fact that you, in 
Louisiana and Alaska and New Jersey, are all threatened by 
these climate changes that we see and that we worry about, the 
sea-level rise and Atlantic storms, the increased air 
pollution, harm to our fisheries. But we're also affected by 
things that happen beyond our shores. We'll be harmed by the 
impacts of global warming that occur across the oceans or on--
even on the other side of the world.
    Now, if the Greenland ice sheet melts into the sea, we'll 
be affected. If the glaciers of Central Asia disappear, taking 
water used for drinking and irrigation for more than a billion 
people with them, we will be affected. If the sea rises and 
washes over homes in Bangladesh, we will be affected. And if a 
range of plant and animal species go extinct, from frogs to sea 
coral to polar bears, we, all of us, will be affected.
    Thousands of scientists around the world have identified 
potential impacts of global warming, and many of their dire 
predictions are already coming true; in some cases, at a rate 
far faster than forecasted. The indicators include increased 
hurricane intensity, the retreat of glaciers, loss of sea ice, 
and our oceans are becoming more acidic. There is no dispute 
that these changes are occurring. Senator Stevens said it very 
clearly, and there is broad scientific consensus, that the 
global warming that we are experiencing is mostly due to human 
activity, not the result of natural climate cycles.
    The most common argument heard from those who oppose prompt 
action to address global warming is that we don't want to wreck 
our economy until we're absolutely sure that the threat is 
real. Well, there are two fallacies to this argument. First, 
reducing global warming will not wreck our economy. In recent 
years, some companies have reduced greenhouse gases and have 
actually found that they've saved money. Second, we can't 
afford to delay taking action until every doubter is convinced. 
Once greenhouse gases enter our atmosphere, they're going to 
remain for a long time, and we can't continue to race toward 
catastrophe, hoping that we can throw the car in reverse at the 
last minute. We've got to slow it down now.
    We've heard these doubters before. Every time a meaningful 
protection of our environment or public health has been 
proposed, they raise reasons as to why we shouldn't be 
concerned about it now. The tobacco industry successfully 
fought efforts to curtail its deadly products for decades, 
based on the claim, ``We just didn't know enough.'' But we did 
know enough to justify taking action.
    In 1994, when President Clinton proposed stronger 
protections from air pollution, industry-funded think tanks 
argued that our economy would be ruined and that barbecues and 
fireworks on the 4th of July would be barred. But after 
President Clinton strengthened air-quality standards, our 
economy did thrive, and fireworks and barbecues continued.
    Now, we know that global warming is occurring. We also know 
it will continue to increase even if we act quickly to flatten 
and then reduce our greenhouse gas emissions. We know that the 
impacts of this warming are already being observed, and that it 
will continue and quicken, particularly if we take no action to 
reverse our current course.
    So, our country's got to act. And this doesn't mean that 
when we act, that we'll see an immediate result. But at some 
point a beginning has to be made, and failure to do so could be 
our greatest failure as a nation and as human beings.
    Now, I'm pleased that we have two panels of witnesses today 
before us. I'm particularly interested in the views of Dr. 
Corell, whose ideas on this matter are well respected, as are 
others in the field of climate science.
    Mr. Chairman, I went down to the South Pole a few years. I 
wanted to see what the National Science Foundation was doing. 
And it seemed to me, at night, that you could almost hear the 
glaciers groaning as there were climate shifts and as the 
temperatures changed. And 70 percent of the world's fresh water 
was stored in those--in that ice. Much of that ice has 
disappeared, and much more of it will disappear.
    And so, once again, Mr. Chairman, I thank you for doing 
this. I look forward to hearing from our witnesses, and sorry 
that we have to delay them, but we'll be back. It's been said 
    Senator Vitter. Thank you, Senator.
    And right now we'll take a very brief recess to vote on the 
Senate floor, and we'll all return absolutely as quickly as 
possible. I apologize for the delay.
    Senator Vitter. We'll reconvene the hearing. Thanks to 
everyone, particularly our witnesses, for their patience.
    We'll start with Panel I, comprised of two individuals. 
First, Dr. Steve Murawski, Director of Scientific Programs and 
Chief Science Advisor for the National Marine Fisheries Service 
and Ecosystem Goal Team Lead with the National Oceanic and 
Atmospheric Administration, and then he'll be followed by Dr. 
Thomas Armstrong, Program Coordinator of the Earth Surface 
Dynamics Program with the U.S. Geological Survey.
    Thank you both for being here. And, Dr. Murawski, please 


    Dr. Murawski. Good afternoon, Chairman Vitter and Chairman 
Stevens. Thanks for the opportunity to testify.
    Among NOAA's diverse missions, our tasks include 
understanding and predicting changes in the Earth's environment 
and acting as the Nation's principal steward of coastal and 
marine resources critical to our Nation's economic, social, and 
environmental needs.
    Climate change is only one of a complex set of interacting 
factors that simultaneously influence the marine ecosystems. It 
is challenging, but vital, for us to isolate the influences of 
individual factors, such as natural and anthropogenic climate 
cycles and other influences, such as pollution, land 
development, fishing pressures, and others on ecosystems.
    In order to manage such a complex set of human activities, 
NOAA is committed to an ecosystem approach that addresses the 
many simultaneous pressures affecting resources, including the 
effects of climate change.
    Because changing climate is one of the significant long-
term influences on marine species, we must meet this challenge 
head-on. Climate-related issues are of particular concern for 
marine ecosystems that include the effects of long-term rising 
sea levels, increasing acidification of the world's oceans, 
bleaching of shallow-water coral reefs, loss of sea ice, and 
rising water temperatures. All of these factors have been 
documented as influencing marine ecosystems, and all are cause 
for concern. As Winston Churchill said, ``The farther backward 
you can look, the farther forward you're likely to see.''
    Paleoclimate and paleoecological indicators provide 
perspective on the scale of recent observed changes in marine 
ecosystems. Over hundreds of thousands of years, numerous ice 
ages and warming events have occurred, and populations have 
responded by changing growth patterns, abundance, and 
geographic location.
    Over the last 10,000 years since the last ice age, there 
were slightly warmer than average conditions during 1200 to 
1400 A.D., slightly cooler conditions from 15- to 1800 A.D.--
that is the Little Ice Age--and an increase in the last 
centuries to temperatures that are the warmest in the last 
    Companion biological records show that, as compared to the 
preceding 1,000 years, organisms and the ecosystems are now 
exhibiting unusual patterns of growth, abundance, distribution, 
and other characteristics.
    Recent changes in the Earth's climate are having observable 
impacts on marine ecosystems and the human communities that 
depend on them. Rising sea levels alter ecosystems and habitat 
in coastal regions. The coastlines of our Atlantic and Gulf 
States, as well as portions of Alaska and the Pacific Islands 
are especially vulnerable to long-term sea-level rise. For 
example, coastal Louisiana is projected to have sea-level rise 
3 to 4 feet over the next century. Factors contributing to sea-
level rise in coastal Louisiana are complex and multifaceted. 
Rising sea levels in coastal Louisiana are having effects on 
coastal marshes that are important to nursery areas for Gulf 
Coast fisheries.
    The oceans are the largest reservoir of carbon dioxide. 
Estimates are that by the middle of this century, atmospheric 
carbon dioxide levels will increase, resulting in a decrease in 
the surface water pH by approximately 0.4 pH units.
    As the oceans become more acidic, more species of marine 
plankton will have a reduced ability to produce protective 
calcium carbonate shells. These plankton species are the base 
of the marine food web, and shifts in the base can have 
cascading consequences through trophic levels. The loss of 
calcium carbonate will also have negative impacts on the 
world's coral reefs, which are areas of the highest 
biodiversity in the ocean. Coral reefs are also extremely 
vulnerable to sea surface temperatures. Rising global 
temperatures over the past 30 years have been accompanied by an 
increase in the extent and frequency of coral bleaching in many 
tropical areas of the world. September of 2005 was, by far, the 
warmest in the eastern Caribbean in the entire 100-year record 
that we have. Many of these areas experienced over 90 percent 
of corals bleached, and 30 percent of the corals have died in 
some of these areas. This loss is significant, as coral reef 
ecosystems are among the most diverse and biologically complex 
areas in the oceans.
    The loss of sea ice has been documented in both the Arctic 
and the Antarctic. The amount and duration of ice cover in the 
southeast Bering Sea has decreased substantially since the 
early 1970s as the southeast Bering Sea has warmed 2 to 3 
degrees Centigrade in the past 10 years. These changes have had 
substantial biological impacts on the distribution and 
abundance of many commercial finfish and shellfish species. 
This means that the resource base supporting individual 
communities has been displaced, affecting the economics of 
fisheries and the communities. Other changes in the food web of 
the Bering Sea have occurred, affecting marine mammals and 
subsistence hunting for them.
    Temperatures in the South Shetland Islands in Antarctica 
have warmed by over 4 degrees Centigrade since the 1940s, and 
the extent of ice around Antarctica has declined appreciably. 
The density of krill, a central link in the Antarctic food web, 
has decreased by more than 90 percent in the region since 1976. 
Declines in krill have been associated with decreasing 
populations of penguins, seals, and other marine life.
    In temperate regions, many marine fish and shellfish 
species have been observed to shift their distributions 
northward in response to warmer waters.
    This is just a sample from the growing body of evidence 
linking climate change to marine ecosystem function. It is our 
challenge to understand these linkages both to better predict 
their effects and to identify the conservation and management 
policies in the face of changing climate that may help to 
mitigate their effects.
    Improving the predictability of ocean responses to a 
changing climate will require improvements in ocean observing, 
research, and modeling. A large broadscale and robust system 
for observing and measuring oceanographic climate and economic 
conditions is essential to better understanding climate change 
effects and ecosystem effects.
    To provide such a comprehensive set of measurements, the 
Administration and NOAA have supported the development of the 
U.S. Integrated Ocean Observing System, or IOOS. The full 
development of IOOS is a high priority for improving our 
understanding of climate effects on marine ecosystems.
    And, last, the President's FY 2007 budget request restores 
significant cuts made by Congress in NOAA's climate program in 
2006. This funding is critical to NOAA's ability to understand 
and study climate change, including the impacts of climate on 
ecosystems. And we urge the Committee to support NOAA's FY 2007 
budget request.
    Thank you, Mr. Chairman. I'd be happy to answer questions.
    [The prepared statement of Dr. Murawski follows:]

Prepared Statement of Steven A. Murawski, Ph.D., Director of Scientific 
 Programs/Chief Science Advisor, National Marine Fisheries Service and 
      Ecosystem Goal Team Lead, National Oceanic and Atmospheric 
                 Administration, Department of Commerce
    Good afternoon, Mr. Chairman and Members of the Committee. My name 
is Steven Murawski, and I am the Director of Scientific Programs and 
Chief Science Advisor at the National Marine Fisheries Service (NMFS), 
within the National Oceanic and Atmospheric Administration (NOAA). I 
also serve as leader of NOAA's Ecosystem Goal Team, which integrates 
the Agency's many ecological activities across its various offices. 
Thank you for inviting NOAA to discuss projected and past effects of 
climate change with a focus on marine and terrestrial ecosystems. Among 
NOAA's diverse missions, our tasks include understanding and predicting 
changes in the Earth's environment and acting as the Nation's principal 
steward of coastal and marine resources critical to our Nation's 
economic, social and environmental needs.
    Today I will focus my remarks on how changes in climate affect 
marine ecosystems, particularly as they relate to NOAA's stewardship 
responsibilities. NOAA's work on climate change and ecosystems relevant 
to this hearing includes observations of the physical environment and 
biota, research to understand the changes in the environment and the 
broader ecosystem, and incorporating projected impacts of climate 
change into NOAA's conservation and management programs for living 
marine resources and ecosystems. Climate change is only one of a 
complex set of factors that influence marine ecosystems. It can be 
difficult to separate the influence of natural climate cycles, recent 
climate change, and other factors such as overfishing, air pollution 
such as sulfates, agricultural run-off, land use changes resulting from 
land fills, drainage practices, uses of pesticides and fertilizers, 
development, recreational facilities and practices, inadequate storm 
water management, and sewage treatment. NOAA is committed to an 
ecosystem approach to resource management that addresses the many 
simultaneous pressures affecting ecosystems.
    This Administration recognizes climate change as a complex and 
important issue and acknowledges human activities are contributing to 
recent observed changes in the climate system. However, scientific 
uncertainties still remain, including how much of the observed warming 
is due to human activities and how large and fast future changes will 
be. In 2002, the Administration created the Climate Change Science 
Program (CCSP; the Federal interagency program focused on climate 
change research) to ensure the Federal Government's efforts and 
resources are used to obtain the best possible scientific knowledge as 
the foundation to address challenging climate change questions and 
support decisionmaking. There is much important research yet to be done 
and CCSP--whose leadership resides in NOAA--is seeking to increase our 
understanding of climate change. Within CCSP there is an Ecosystem 
Interagency Working Group which is currently examining a variety of 
topics relevant to today's hearing, including: (1) the use of 
integrated modeling systems, observations, and process studies to 
project the effects of climate variability and change on near-coastal 
and marine ecosystems and communities; (2) combined effects of changes 
in land use and climate on non-point sources of pollution entering 
estuaries; and (3) a long-term study of the western U.S. mountains and 
the relationship of observed sudden ecosystem changes to changes in 
climate conditions.
    The Climate Change Science Program is a coordinated effort across 
13 agencies (U.S. Agency for International Development; Department of 
Agriculture; Department of Commerce, National Oceanic and Atmospheric 
Administration and National Institute of Standards and Technology; 
Department of Defense; Department of Energy; Department of Health and 
Human Services, National Institutes of Health; Department of State; 
Department of Transportation; Department of the Interior, U.S. 
Geological Survey; Environmental Protection Agency; National 
Aeronautics and Space Administration; National Science Foundation; and 
the Smithsonian Institution), 12 of which fund CCSP research. Funding 
for NOAA's CCSP initiatives are included within the NOAA Climate 
Program. The fiscal 2007 President's budget request for NOAA includes 
spending for CCSP near-term research focus areas, including integrating 
new remote-sensing observations with expanded observations to build the 
next generation of climate prediction capabilities; development of an 
integrated Earth system analysis capability; integrating of water cycle 
observations, research and modeling; using global LANDSAT data to 
answer critical climate questions; an integrated North American Carbon 
Program; understanding the impacts of climate variability and change on 
ecosystem productivity and biodiversity; coping with drought through 
research and regional Partnerships; the International Polar Year; and 
an Integrated Ocean Observing System. The President's budget restores 
cuts made by Congress to NOAA's Climate Program in 2006, particularly 
in the area of Research Supercomputing, critical to NOAA's ability to 
reduce some of the highest uncertainties in understanding impacts of 
climate variability and change. We urge the Committee to support the FY 
2007 President's budget request for NOAA.
    In my testimony today I will: (a) provide information on NOAA's 
contributions relevant to climate change science and links to effects 
on marine ecosystems, (b) detail the importance of understanding 
climate-ecosystem links both for the affected marine areas and the 
human communities dependent upon them, (c) briefly describe some 
paleontological observations of how ecosystems have changed in response 
to climate variations in the past, and (d) review some contemporary 
observed changes in marine ecosystems thought to be related to changes 
in the Earth's climate and issues surrounding them. Finally, I will 
outline some of the scientific challenges and needs for improving 
science to better define ecosystem impacts and inform conservation and 
management strategies for living marine resources taking into account 
climate impacts.
NOAA's Roles in Climate and Ecosystem Sciences
    Within the climate science community, NOAA is a recognized leader 
both nationally and internationally. Our scientists actively 
participate in many important national and international climate 
working groups and assessment activities. One of NOAA's mission goals 
is to ``understand climate variability and change to enhance society's 
ability to plan and respond.'' NOAA is the only Federal agency that 
provides operational climate forecasts and information services 
(nationally and internationally). NOAA is the leader in implementing 
the Global Ocean Observing System (NOAA contributes 51 percent of the 
world-wide observations to GOOS, not including satellite observations). 
NOAA also provides scientific leadership for the Intergovernmental 
Panel for Climate Change Working Group I and CCSP. To better serve the 
Nation, NOAA recently created a Climate Program Office (CPO) to provide 
enhanced services and information for better management of climate 
sensitive sectors, such as energy, agriculture, water, and living 
marine resources, through observations, analyses and predictions, and 
sustained user interaction. Services include assessments and 
predictions of climate change and variability on timescales ranging 
from weeks to decades.
    Within the ecosystem community, NOAA's ecosystem researchers have 
been at the forefront of establishing links between ocean variability 
and impacts on marine ecosystems. NOAA has funded some research 
programs specifically dedicated to evaluating impacts of changes in the 
physical environment on marine resources. These include a program 
jointly undertaken with the National Science Foundation called GLOBEC 
(Global Ocean Ecosystem Dynamics), which just last week co-hosted a 
symposium on ``Climate variability and ecosystem impacts on the North 
Pacific'' with PICES (the North Pacific Marine Science Organization of 
which the U.S. is also a member). An exclusively NOAA program called 
NPCREP (North Pacific Climate Regimes and Ecosystem Productivity) seeks 
to improve climate-ecosystem science in the Alaskan Large Marine 
Ecosystem complex. Even more information on the impacts of climate on 
marine ecosystems is derived from NOAA's many observing programs 
established to aid in the management of fisheries, protected species, 
marine sanctuaries, corals and other specific Agency mandates.
    These data, primarily collected in support of NOAA's ecosystem 
stewardship authorities, provide a wealth of information for 
interpreting climate impacts when combined with NOAA's climate, 
oceanographic and weather information. Results of these analyses have 
been widely disseminated and NOAA's contributions to the emerging 
science of ecosystem impacts of climate change have been significant. 
However, a greater understanding of the full range of climate induced 
impacts on ecosystems will require us to increase our observation of 
ecosystems in relation to variable climate forcing and focus our 
research on the mechanisms through which ecosystems are affected. In 
this way we can develop quantitative assessments and projections of 
climate's ecological impacts, including impacts on the resources on 
which human communities rely.
Why are Links between Climate and Marine Ecosystems So Important?
    Irrespective of the ultimate causality, changes in the world's 
climate has resulted in changes in marine ecosystems, on several 
different time scales, affecting the abundance, distribution and 
feeding relationships among components of many marine communities 
\1\, \2\, \3\, \4\, 
\5\, \6\ While we are still working toward a complete 
understanding of the causes of the observed phenomena, recent 
projections indicate that a number of climate change scenarios have the 
potential to affect marine ecosystems in even more fundamental ways. 
These changes are related both to long-term trends in the ocean 
environment and to the cyclic variation in ocean conditions observed in 
many areas. These changes are important in their own right, but even 
more so because of the dependence of many of our coastal communities on 
living marine resources--for food, recreation, and cultural 
fulfillment. Over half of the U.S. population now lives within 100 
miles of the coast, and this proportion is increasing dramatically. Our 
$60 billion per year seafood industry, marine tourism industries, 
recreational activities, and the very existence of some communities may 
be dependent on changing ocean conditions affecting marine ecosystems.
    Changing climate is one of the most significant long-term 
influences on the structure and function of marine ecosystems and must 
therefore be accounted for in NOAA's management and stewardship goals 
to ensure healthy and productive ocean environments. Changes and 
variations in climate may directly or indirectly impact marine 
ecosystems. This includes changes and variations of sea surface 
temperature, ocean heat content, sea level, sea ice extent, freshwater 
inflow and salinity, oceanic circulation and currents, pH, and carbon 
inventories. Each of these properties of the global ocean is being 
measured to varying degrees by NOAA. Through the continued collection 
of data and the implementation and integration of observing systems, we 
strive to create longer, more globally inclusive data records that will 
improve our understanding of climate change and our ability to reliably 
predict impacts on marine ecosystems over time scales of interest to 
our constituents now (e.g., 5-10 year time horizon) and in the future.
A Paleontological Perspective on the Impacts of Climate Change on 
        Marine Ecosystems
    The paleoclimate record provides a long view of how populations and 
entire ecosystems have responded to climate change over hundreds to 
thousands of years. Many sources of paleoclimate data are from 
biological indicators such as tree rings, corals, and fossil plankton. 
By comparing the time series from biological indicators with 
paleoclimate data from non-biological material such as ice cores, 
boreholes, and cave stalagmites, one can reconstruct not only how 
climate has changed, but also how marine and terrestrial populations 
have responded.
    Over hundreds of thousands of years, ice ages have come and gone, 
and populations have responded by changing growth patterns, abundance 
and geographic location. Remarkably only a few documented extinctions 
occurred in terrestrial and marine ecosystems during ice age cycles, 
apart from the extinction of the Pleistocene megafauna (e.g., the 
woolly mammoth). Just as the changes in climate during the ice ages 
were large and sometimes abrupt, ecosystem changes were similarly large 
and abrupt. For example, at the end of the last ice age, pollen from 
lake sediments indicate an abrupt northward migration and establishment 
of the modern biomes across North America,\7\ while in the adjacent 
oceans fossil plankton from marine sediments reveal that the region 
where certain plankton species were abundant also moved to higher 
    While these changes in the ocean environment were abrupt compared 
to the radiation changes that caused the ice ages, the changes were 
slow compared to the changes occurring in the current millennium. The 
end-of-the-ice-age ecosystem changes occurred over thousands of years. 
Over the last 10,000 years climate has remained relatively stable apart 
from small changes caused by the changes in seasonal solar radiation. 
Over the past 1,000 years, where the paleoclimate record is most 
complete, climate has been even more constant except for the recent 
trends in temperature and rainfall. The climate of the last 1,000 years 
can be characterized as: 1200-1400 AD--slightly warmer than average 
conditions; 1500-1800 AD--slightly cooler than average conditions; and 
1900-2000 AD--an increase in the last centuries to temperatures that 
are likely to be the warmest in the last millennium.\9\, 
\10\ Companion biological records show that organisms and ecosystems 
are changing in growth pattern, abundance, and other characteristics in 
ways that are unusual compared to the preceding 1,000 years. Detailed 
information on terrestrial and marine ecosystem responses to past 
climate change is detailed on the NOAA Paleoclimatology website 
(www.ncdc.noaa.gov/paleo). One selected example relevant to marine 
ecosystems involves the long record of sockeye salmon populations in 
    The paleoclimate record of sockeye salmon from Alaskan lakes 
reveals the difficult task of separating the influence of natural 
climate cycles, recent climate change, and fishing pressure on salmon 
abundance. Sockeye salmon return to lakes in Alaska to spawn, and their 
remains are reflected in chemical (e.g., nitrogen-15) concentrations in 
lake sediments, creating a 2000 year-long record of salmon abundance. 
Dr. Bruce Finney, from the University of Alaska, and his colleagues 
correlated centuries-long cycles in salmon abundance with climate 
variations from other paleo proxies, demonstrating the existence of 
natural cycles in salmon populations prior to significant human 
activity in the region.\11\ Near the end of the record the decline due 
to intense fishing pressure in the last century is also evident. Finney 
and colleagues note that natural cycles in salmon abundance appear out 
of phase with the abundance of other fish species farther south in the 
California Current system, a pattern they also attribute to natural 
climate variability. In addition to fish abundance, paleo-ecological 
records have also been developed for plankton that form the base of the 
food chain. Compared to the fish proxies, the plankton records are more 
complete and subject to fewer uncertainties. While these records are 
continuously being developed, the records published so far document a 
clear link between climate change and marine ecosystems. One important 
conclusion from this work is that marine ecosystems are sensitive to 
even small changes in climate.
Current and Projected Impacts of Climate Change on Marine Ecosystems 
        and Living Marine Resources
Impacts of Sea Level Rise on Ecosystems
    Sea level rise is projected to accelerate during the 21st century, 
with the most significant impacts in low-lying regions where subsidence 
and erosion problems already exist. Rising sea level has worldwide 
consequences because of its potential to alter ecosystems and habitat 
in coastal regions. Sea level rise and global climate change issues in 
the coastal zone include:

   Higher (deeper) and more frequent flooding of wetlands and 
        adjacent shores;

   Increased flooding due to more intense storm surge from 
        severe coastal storms;

   Increased wave energy in the nearshore area;

   Upward and land-ward migration of beaches;

   Accelerated coastal retreat and erosion;

   Saltwater intrusion into coastal freshwater aquifers;

   Damage to coastal infrastructure; and

   Broad impacts on the coastal economy.

    The coastlines of our Atlantic and Gulf states, as well as portions 
of the Alaska coastline are especially vulnerable to long-term sea 
level rise. The slope of these areas is so gentle that any small rise 
in sea level can produce a large inland shift of shoreline.
    Sea level rise threatens to alter wetland ecosystems. Sea level 
rise may also result in increased susceptibility to nutrient-related 
eutrophication, due to changes in estuarine circulation. Changes in the 
wetland and estuarine processes will affect resident marine organisms 
and the fisheries dependent upon them.
    NOAA has maintained long-term continuously operating stations of 
the National Water Level Observation Network (NWLON), and has recently 
documented the relative sea level trends at all of the longest-term 
stations (1854-present). The map below (also available at http://
tidesandcurrents.noaa.gov/sltrends/slrmap.html) shows sea level trends 
for the United States for those locations where tide stations exist. 
This map provides an indication of the differing rates of relative sea 
level rise (vertical land and sea level motion combined) around the 
United States. There is a general scientific agreement that sea level 
rise is occurring at a global average rate of 2 mm per year. Referring 
to the map the mid-Atlantic and Gulf Coast are experiencing 3-5 mm and 
5-15 mm per year rise in sea level, respectively.

    One area particularly vulnerable to sea level rise is coastal 
Louisiana. The graphic above illustrates that these areas are projected 
to have sea levels rise 3-4 feet over the next century. Factors 
contributing to sea level rise in coastal Louisiana are complex and 
multifaceted, including land subsidence due to petroleum extraction, 
declining sediment loads deposited from rivers into the marshes, land 
use practices exacerbating wetlands loss, and rising sea levels due to 
global climate change and other factors. Whatever the causes, a 3-4 
foot rise in sea level in coastal Louisiana will have profound effects 
on marine resources, since coastal marshes there are important nursery 
areas for most of the valuable living resources (e.g., shrimp, oysters, 
many finfish species) in the Gulf of Mexico. In addition, loss of 
Louisiana's coastal marshes to sea level rise makes coastal communities 
much more vulnerable to recurring storm events.
    The Northwestern Hawaiian Islands (NWHI) are of particular concern 
with respect to sea level rise. The NWHI have high conservation value 
due to their concentration of endemic, endangered and threatened 
species, and large numbers of nesting seabirds. Most of these islands 
are low-lying and therefore potentially vulnerable to increases in 
global average sea level. The potential for NWHI habitat loss was 
recently assessed by the NMFS Pacific Islands Fisheries Science Center, 
by creating topographic models of several islands and atolls in the 
NWHI and evaluating the potential effects of sea-level rise by 2100 
under a range of basic passive flooding scenarios. Projected 
terrestrial habitat loss varied greatly among islands: 3 percent to 65 
percent under a median scenario (48-cm rise), and 5 percent to 75 
percent under the maximum scenario (88-cm rise). Spring tides may 
repeatedly inundate all land below 89 cm (median scenario) and 129 cm 
(maximum scenario) in elevation. Sea level is expected to continue 
increasing after 2100, which would have greater impact on atolls such 
as French Frigate Shoals and Pearl and Hermes Reef, where virtually all 
land is less than 2 m above sea level. Higher islands such as 
Lisianski, Laysan, Necker, and Nihoa may provide longer-term refuges 
for species. The effects of habitat loss on NWHI biota are difficult to 
predict, but may be greatest for endangered Hawaiian monk seals, 
threatened Hawaiian green sea turtles, and the endangered Laysan finch 
at Pearl and Hermes Reef.
Ocean Acidification
    The oceans are the largest natural long-term reservoir for carbon 
dioxide, absorbing approximately one-third of the carbon dioxide added 
to the atmosphere by human activities each year. Over the past 200 
years the oceans have absorbed 525 billion tons of carbon dioxide from 
the atmosphere, or nearly half of the fossil fuel carbon emissions over 
this period. Over the next millennium, the global oceans are expected 
to absorb approximately 90 percent of the carbon dioxide emitted to the 
    For over 20 years, NOAA has participated in decadal surveys of the 
world oceans, documenting the ocean's response to increasing amounts of 
carbon dioxide being emitted to the atmosphere by human activities. 
These surveys confirm that oceans are absorbing increasing amounts of 
carbon dioxide. Estimates of future atmospheric and oceanic carbon 
dioxide concentrations, based on the Intergovernmental Panel on Climate 
Change emission scenarios and general circulation models, indicate that 
by the middle of this century atmospheric carbon dioxide levels could 
reach more than 500 parts per million (ppm), and near the end of the 
century they could be over 800 ppm. This would result in a surface 
water pH decrease of approximately 0.4 pH units as the ocean becomes 
more acidic, and the carbonate ion concentration would decrease almost 
50 percent by the end of the century. To put this in historical 
perspective, this surface ocean pH decrease would be lower than it has 
been for more than 20 million years.\13\
    Recent studies indicate that such changes in water chemistry, or 
ocean acidification as the phenomenon is called, would have effects on 
marine life, such as corals and plankton.\13\, \14\ The 
carbonate chemistry of seawater has a direct impact on the dissolution 
rates of calcifying organisms (coral reefs and marine plankton). As the 
pH of the oceans decreases and becomes more acidic, some species of 
marine algae and plankton will have a reduced ability to produce 
protective calcium carbonate shells. This makes it more difficult for 
organisms that utilize calcium carbonate in their skeletons or shells 
to build and maintain their structures. These organisms form the 
foundation of the food chain, upon which other marine organisms feed. 
Decreased calcification may also compromise the fitness or success of 
these organisms and could shift the competitive advantage toward 
organisms not dependent on calcium carbonate. Carbonate skeletal 
structures are likely to be weaker and more susceptible to dissolution 
and erosion. There is paleooceangraphic evidence that during the last 
high CO2 regime (55 million years ago) increased ocean 
acidification was associated with mass extinctions of phytoplankton 
species, followed by a recovery period of about 80,000 years.\15\ 
Because of the importance of phytoplankton to marine food webs, 
biodiversity and productivity of the oceans may be altered \14\, which 
may result in adverse impacts on fishing, tourism, and other economies 
that rely on the continued health of our oceans.
    Recent findings indicate that such conditions could develop within 
decades at high latitudes.\14\ This will likely have impacts on high 
latitude ecosystems because pteropods, a shelled, swimming mollusk, is 
a significant prey item for fish in these regions. It is important to 
gain a better understanding of how ocean chemistry and biology will 
respond to higher carbon dioxide conditions so that predictive models 
of the processes and their impacts on marine ecosystems can be 
Coral Bleaching Events
    Coral reef ecosystems are among the most diverse and biologically 
complex ecosystems on Earth and provide resources and services worth 
billions of dollars each year to the United States economy and 
economies worldwide. Coral reefs support more species per unit area 
than any other marine environment, including about 4,000 species of 
fish, 800 species of hard coral and thousands of other species. 
Approximately half of all federally-managed fish species depend on 
coral reefs and related habitats for a portion of their life cycles. 
The National Marine Fisheries Service estimates the annual commercial 
value of U.S. fisheries from coral reefs is over $100 million. Local 
economies also receive billions of dollars from visitors to reefs 
through diving tours, recreational fishing trips, hotels, restaurants, 
and other businesses based near reef ecosystems. In the Florida Keys, 
for example, coral reefs attract more than $1.2 billion annually from 
tourism. In addition, coral reef structures buffer shorelines against 
waves, storms and floods, helping to prevent loss of life, property 
damage and erosion.
    Coral reefs are extremely vulnerable to increased sea surface 
temperatures. As global temperatures have risen over the past 30 years, 
there has been a corresponding increase in the extent and frequency of 
extremely high sea surface temperatures and coral bleaching events in 
many tropical regions.\4\, \16\
    Coral bleaching is a response of corals to unusual levels of stress 
primarily thought to be associated with light and ocean temperature 
extremes. Bleaching occurs when corals expel their symbiotic algae and 
lose their algal pigment. Loss of the symbiotic algae leaves the coral 
tissue pale to clear and, in extreme cases, causes a bleached 
appearance. Corals often recover from mild bleaching. However, if the 
stress is prolonged and/or intense, the corals may die or weaken, 
causing them to be more susceptible to disease and other stressors.
    Coral bleaching has occurred in both small localized events and at 
large scales. Although many stressors can cause bleaching, mass 
bleaching events have almost exclusively been linked to unusually high 
ocean temperatures. There is still much that we do not know about the 
impacts of bleaching-associated mass coral mortality on: (1) the 
function of coral reef ecosystems; (2) the associated fisheries; and 
(3) the value (loss) to recreation and tourism industries.
    Through satellite and in situ monitoring of thermal stress, NOAA 
tracks the conditions that may lead to coral bleaching. When the data 
show that conditions are conducive to bleaching, NOAA provides watches, 
warnings, and alerts to users throughout the globe through NOAA's Coral 
Reef Watch project and Integrated Coral Observing Network. Coral 
bleaching alerts allow managers and scientists to deploy monitoring 
efforts which can document the severity and impacts of the bleaching to 
improve our understanding of the causes and consequences of coral 
    Large scale or mass bleaching events were first documented in the 
eastern Pacific in the early 1980s in association with the El Nino 
Southern Oscillation.\16\ In 1997-1998, coral bleaching became a global 
problem when a strong El Nino (period of warmer than average water 
temperature), followed by a La Nina (period of colder than average 
water temperature) caused unprecedented coral bleaching and mortality 
    However, coral bleaching events are not only tied to the El Nino/La 
Nina phenomena. In 2005, a year lacking El Nino or La Nina climate 
patterns, unusually warm temperatures were recorded in the tropical 
North Atlantic, Caribbean, and Gulf of Mexico. Corals in the Caribbean 
region experienced temperatures in 2005 that greatly exceeded any of 
the previous 20 years. While the thermal stress in the Caribbean has 
increased over the last 20 years, 2005 was a major anomaly from the 
upward trend in temperatures there. As a result of NOAA satellite and 
in situ monitoring, we were able to alert managers and scientists to 
this temperature anomaly. The unusually warm temperatures gave rise to 
the most intense coral bleaching event ever observed in the Caribbean. 
NOAA is working with local partners in Florida, Puerto Rico and the 
U.S. Virgin Islands to better assess the impacts from the 2005 
bleaching event. It is clear that mass bleaching is a serious concern 
to the communities that depend upon these resources.
    Preliminary analyses by NOAA show that the cumulative thermal 
stress for 2005 was 50 percent larger than the cumulative stress of the 
prior 20 years combined.\18\ September 2005 was by far the warmest 
September in the Eastern Caribbean in the entire 100-year record. Many 
areas, including the U.S. Virgin Islands, averaged over 90 percent of 
their corals bleached and some have already lost 30 percent of these 
corals due to direct thermal stress or subsequent disease. NOAA is 
currently analyzing the impact of this bleaching event on already 
vulnerable elkhorn and staghorn coral species. These two species have 
been proposed for listing as ``threatened'' under the Endangered 
Species Act.
    NOAA and the Department of the Interior (DOI) are leading the 
interagency effort of the U.S. Coral Reef Task Force to respond to and 
assess the massive coral bleaching event in the Caribbean region in 
2005. This effort has engaged many government and non-government 
partners from across the region to assess the impacts of the massive 
event and make recommendations on how to prepare for and address future 
events. For example, NOAA, DOI, and the National Aeronautics and Space 
Administration (NASA) conducted missions in October and December 2005 
to examine the extent of bleaching and recovery/mortality of corals 
within the Buck Island Reef National Monument, as well as obtain aerial 
and hyperspectral imagery to quantify the extent of bleaching within 
St. Croix, St. John, and southwestern Puerto Rico. Initial findings 
indicate that in many areas, including the U.S. Virgin Islands, over 90 
percent of coral cover had bleached. While some recovery had occurred 
by December, hardest hit areas have already had over 30 percent of 
their coral die. Further analyses are currently underway.
Impacts of Climate on Fisheries and Protected Resources
    NOAA has stewardship responsibilities for coastal and living marine 
resources from over 90 Acts of Congress. Resources managed under these 
authorities are extremely valuable to the country, with fisheries alone 
contributing over $60 billion a year and 520,000 jobs to the U.S. 
economy. Interannual climate variability (e.g., El Nino, La Nina) and 
trends (e.g. global warming) can cause profound geographic shifts in 
marine ecosystems and are of great consequence to fishery-dependent 
communities. Climate variability/change impacts environmental 
conditions on multiple time scales, ranging from interannual to 
decadal; since Earth's temperature is warming on a global scale, it is 
important to assess the environmental impacts on large marine 
    In the past several decades, there have been significant changes in 
the distribution, growth, and abundance of living marine resources 
resulting from changes in ocean temperatures and related ocean 
conditions. These changes have occurred in polar regions, in temperate 
waters, and in the tropics. These changes have altered the productivity 
and structure of marine food webs and change the flow of goods and 
services to coastal communities. Below are cited some specific examples 
of ecosystems changes documented by NOAA that are likely linked to 
climate variations.
    Polar Regions: Loss of sea ice at high latitudes has been 
documented in a number of recent scientific articles and other forums. 
Until recently, the northern Bering Sea ecosystem had extensive 
seasonal sea ice cover and high water column and sediment carbon 
production. Recently, NOAA researchers and other colleagues have 
demonstrated that these ecosystems are shifting away from these 
characteristics.\2\, \19\ The amount and duration of ice 
coverage in the southeast Bering Sea has decreased substantially since 
the early 1970s. In addition, the southeast Bering Sea has warmed 2-3+C 
over the past 10 years. Recent work has documented differences in ice 
coverage and thickness as far north as St. Lawrence Island in the 
northern Bering Sea. These changes have substantial impacts to both 
arctic and subarctic marine species in the area. For example, Greenland 
turbot, a flatfish that prefers cold temperatures, has shown a steady 
decrease in abundance since the mid-1970s. During this same time 
period, abundance of walleye pollock, which prefers warmer waters, has 
increased dramatically, with the present landings valued at $295 
million per year. Bering Sea snow crab distribution has shifted 
northward, and pollock distribution in the Bering Sea may soon follow, 
affecting ecosystem interactions, fishery assessment surveys and the 
economics of the fishing fleet which have to travel farther and spend 
more days at sea to find and capture the same number of fish. In 
addition, juvenile pollock act as forage fish in this ecosystem and 
changes in their abundance, size, or distribution has the potential to 
affect marine mammals.
    Changes in the Bering Sea marine mammals have also been observed. 
Gray whales have shifted their distributions northward, apparently in 
response to decreases in sea ice and declines in their preferred prey 
on the ocean floor.\20\ In addition, ice-dependent seals (ring, 
spotted, bearded, and ribbon seals) require ice for parts of their life 
history (molting and pupping) and there is concern that these animals 
are being forced away from suitable feeding grounds as the ice 
retreats.\21\ Similar concerns have been expressed regarding polar bear 
and walrus populations in Alaska.\21\, \22\ These changes to 
the ecosystem have clear implications for subsistence harvests in 
Alaskan native communities.
    In addition to the effects of climate variability and change on the 
distribution and abundance of commercially important species of fish 
and shellfish, as well as marine mammal species important to 
subsistence hunters, the reduction in the extent and duration of sea 
ice in the Bering and Chukchi Seas in recent years has led to serious 
erosion problems for several remote villages and towns, including 
Barrow, Pt. Lay, Wales, and particularly in the village of Shishmaref. 
In these villages, traditionally the sea ice would buffer the impacts 
of storm driven waves during the winter and spring. With less sea ice, 
wave action is causing serious erosion problems and threatening 
buildings and roads. To better predict the likely rate at which erosion 
will impact this area, requires better information on trends in sea 
level height, extent and duration of sea ice, and storm frequency.
    Decreases in sea ice appear to be affecting other ecosystems as 
well. The annual air temperature near the South Shetland Islands, 
Antarctica has warmed by over 4+C since the 1940s \23\ and ice extent 
around areas of Antarctica monitored by NOAA has declined 
appreciably.\24\ Air temperatures at Palmer station are closely 
correlated with the annual amount of ice cover. While air temperatures 
in the Shetlands have increased, the density of krill, a shrimp-like 
organism that is the central link in the Antarctic food web has 
decreased by more than 90 percent in the region since 1976.\25\ Warming 
of Antarctic waters and loss of ice affect predator (seals, penguins, 
whales, etc.) and krill populations in the Southern Ocean in several 
ways. Krill are a keystone species in the Antarctic because so many 
species (fish, seals, penguins, sea birds, whales) feed upon them. 
Declines in krill populations will negatively affect populations of 
krill predators. Over the past two decades, populations of Adelie and 
chinstrap penguins have declined significantly on the Antarctic 
Peninsula, and the average reproduction rate of fur seals in the South 
Shetlands has slowed as well. Years of low sea ice appear to be 
associated with low krill production but relatively high populations of 
salps (a gelatinous zooplankton, of little nutritional value to krill 
predators).\5\ In addition, some predators are dependent upon sea ice 
to haul out and rest during the over-wintering migrations, and declines 
and shifts in sea-ice will impact their movements and distributions. 
Thus, climate-related changes in the environment of Antarctica have had 
and will likely continue to have important consequences for the marine 
ecosystems of the region.
    Temperate Regions: Climate-induced shifts in species distribution 
and abundance have been observed in the temperate regions of the 
Atlantic and Pacific. Many marine fish species have been observed to 
shift their distributions northward in response to warming 
waters.\3\, \26\ Populations of surf clams, an economically 
important species along the mid-Atlantic coast of the United States 
(particularly from New Jersey to Virginia), show evidence of increased 
mortality in the southern regions of their territory. This is thought 
to be due to elevated sea temperatures.\27\ These populations are also 
susceptible to low oxygen events that may increase in frequency and 
severity with the anticipated warming in the Mid-Atlantic region. A 
severe low oxygen event off New Jersey in 1976 caused economic losses 
of over $70 million to the clam fishery and it was many years before 
the clam populations recovered.\28\ Declining recruitment levels of 
some species linked to cooler water temperature (e.g., yellowtail 
flounder in Southern New England) impedes rebuilding of the stock to 
provide long-term sustainable fisheries.
    In the western North Atlantic, a study of the distribution patterns 
of three dozen pelagic and demersal fish species was conducted using 
consistent data from over three decades to examine impacts of water 
temperature changes on geographic distributions.\25\ This study 
revealed a set of species whose center of distribution shifts from 0.5-
0.9 degrees of latitude pole-ward for each degree Celsius of water 
temperature increase. Because not all species responded in this manner, 
there is likelihood that the structure of predator-prey relationships 
in the ecosystem would be altered under a scenario of long term warming 
of Atlantic waters.\17\, \24\ Studies from the eastern 
Atlantic have drawn similar conclusions. In the southern North Sea, 
there has been a gradual replacement of species with primarily cold 
water affinities with ones previously associated with more southern 
    In the California Current ecosystem there have also been sustained 
shifts in the dominance of various fish species over the past few 
decades. Off California, the dominant fish fauna has shifted from cold-
water species to ones of primarily warm water affinities. These changes 
have occurred gradually over a sustained two decade period, and are 
confounded by overfishing of many of the stocks.
    From the 1970s through the 1990s there were overall declines in the 
California fishery landings that coincided with an unprecedented period 
of unusually warm ocean conditions and a decline in ecosystem 
productivity.\30\ Changes in the survival of Pacific salmon appear to 
follow a decadal-scale cycle (the Pacific Decadal Oscillation, or PDO), 
with salmon survivorship being relatively high during the cool periods 
and low during warm periods.\6\ In addition the California sardine 
collapse in the 1940s was driven in part by a shift to cooler 
conditions and a different ecosystem structure. Ocean sediment records 
indicate sardine biomass has fluctuated for centuries on time scales 
associated with decadal-scale shifts in the north Pacific 
    Climate and weather patterns over the North Atlantic are strongly 
influenced by the relative strengths of two large-scale atmospheric 
pressure cells--the Icelandic Low and a high pressure system generally 
centered over the Azores in the eastern Atlantic. A deepening of the 
Icelandic Low often corresponds with a strengthening of the Azores High 
and vice versa. This see-saw pattern is called the North Atlantic 
Oscillation (NAO) and a simple index of its state is given by the 
difference in sea level pressure between the Azores and Iceland.
    When the NAO index is positive, we see an increase in westerly 
winds across the Atlantic and in precipitation over southeastern 
Canada, the eastern seaboard of the United States, and northwestern 
Europe.\3\ We also see increased storm activity tracking toward Europe. 
Water temperatures are markedly low off Labrador and northern 
Newfoundland, and warm off the United States. Conversely, when the NAO 
index is negative, we have decreased storminess, and drier conditions 
over southeastern Canada, and colder conditions over the eastern United 
States and northwestern Europe. Water temperatures are warmer off 
Labrador and Newfoundland, but cooler off the eastern United States. 
These changes in the state of the North Atlantic Oscillation show a 
tendency to persist on decadal time scales. The NAO was generally 
positive during the 1980s and 1990s but has shown a tendency to 
decrease since about the year 2000.
    Variation in the NAO has very different effects on cod recruitment 
on the western and eastern Atlantic.\3\ The direction of the NAO effect 
on cod recruitment exhibits patterns consistent with the regional 
manifestation of the NAO in the North Atlantic, with a coherence in the 
NAO effect in northern Canada and Iceland and between southern Canada-
United States and western Europe. The decline in cod in areas such as 
the North Sea has been linked to the interplay of over-exploitation and 
changes in the planktonic ecosystem affecting the food supply of larval 
cod (which is in turn affected by the NAO). Specifically, the supply of 
the copepod Calanus finmarchicus declined during positive NAO 
conditions and was replaced by smaller bodied species, apparently less 
suitable as food for larval cod.
    In the Northwest Atlantic, researchers have suggested a linkage 
between oceanographic conditions related to the North Atlantic 
Oscillation, abundance of the copepod Calanus finmarchicus, and the 
calving success of the endangered right whale in Gulf of Maine.\32\
    Abundance of adult Calanus declined with these water mass changes 
and a concomitant decline in the birth rate of right whales was 
observed. The decline in the calving success comes at a time when other 
human impacts such as ship strikes threaten recovery of this species. 
These observations suggest that climate-induced changes can have far 
reaching ramifications for commercially important fish species 
throughout the North Atlantic and for critically endangered marine 
mammal species.
    These examples of climate-related effects on marine ecosystems are 
just a sample from the growing body of evidence linking climate change 
to marine ecosystem function. All of these changes, whether trended or 
variable over some time scale, may have profound implications for the 
health and viability of marine ecosystems and for the human communities 
that are dependent upon them. It is our challenge to understand these 
linkages both to better predict their effects and to identify the 
conservation and management policies in the face of climate variability 
and change that may help to mitigate their effects.
    Various management authorities have responded. For example, the 
Pacific Fisheries Management Council routinely takes into account 
decadal-scale changes in marine productivity regimes when setting 
harvest policies for Pacific groundfish and other species. Similar 
management responses are being used or contemplated in other living 
marine resource arenas in which NOAA participates.
Ongoing Challenges for Improving Climate and Ecosystems Information
    Marine ecosystems and their component parts have proved to be 
sentinels of climate change and ocean variability. Changes in living 
marine resources, when observed at proper scales, give us new 
information about how changes in climate are affecting the Earth, and 
have opened new avenues of research into understanding the importance 
of human activities contributing to these observed changes. It is vital 
that we improve our understanding of past, current and projected 
ecosystem impacts of climate change in order to improve the stewardship 
of these resources. Management policies we use in living marine 
resource management can either help mitigate or exacerbate changes due 
to impacts of climate variation. Below I detail a few of NOAA's 
scientific priorities in improving the predictability of ecosystem 
responses to climate change.
Regional Climatologies
    Regional impacts of climate variability and change are important 
and are being studied. In fact, some region-specific modeling predicts 
that part of the planet--and the marine environment--will experience 
cooler and/or wetter conditions, while other areas will be hotter and 
drier. Therefore, regional ecosystem responses may result in stable or 
increasing resources in one region while at the same time resulting in 
declines in abundance and distribution shifts elsewhere.
    Understanding these regional impacts on marine and associated 
terrestrial ecosystems will require more detailed regional models and 
data linking global climate variations to regional atmospheric and 
ocean conditions. This requirement is consistent with NOAA's focus over 
the last 5 years to integrate multidisciplinary research at the Large 
Marine Ecosystem level. Eight such marine ecosystems have been 
recognized in the U.S. Exclusive Economic Zone. It is at the ecosystem 
scale where we expect to be able to fully realize how anthropogenic 
effects (e.g., fishing, land use practices, pollution) and naturally 
driven environmental variation combine to produce the current abundance 
levels and composition of species in each of our marine ecosystems.
    The following will help improve our understanding the ecosystem 
consequences of climate change:
Improved Climate and Ecosystem Modeling
    Extreme weather events as well as long term trends in atmospheric 
and ocean conditions necessitate that we further improve our predictive 
understanding of the climate system and its impacts on ecosystems. To 
do so, NOAA believes that expanded Earth and ecosystems modeling could 
serve as a tool for studies of: (1) the impacts of climate variability 
and change on land ecosystems, ocean ecosystems and carbon cycling; (2) 
the strength of ecological and carbon feedbacks on climate (e.g. the 
effects of increasing atmospheric carbon dioxide on plant growth, which 
in turn affects distributions of atmospheric carbon dioxide); and (3) 
improved predictions of the impacts of climate trends on regional large 
marine ecosystems and their species. An expanded Earth and ecosystems 
model capability would take advantage of the current suite of weather, 
air quality, climate variability, and ecosystem models to include 
biogeochemical cycling, dynamic vegetation, atmospheric chemistry, and 
anthropogenic forcing (e.g. carbon and aerosols) of climate. Existing 
hydrodynamic models of ocean circulation would be expanded to include 
trophic interactions, primary productivity, and spatial distributions 
and movement models for specific taxa, among other ecological 
phenomena. It would employ a unified modeling framework, enabling 
integration of a comprehensive suite of physics, assimilation, 
biogeochemical, and ecosystem model components.
    As model development progresses, components will be expanded to 
include: (a) a land model (currently under evaluation) that simulates 
dynamic land vegetation and land use changes, as well as the exchange 
of water and energy between land, vegetation, and atmosphere; (b) a 
comprehensive ocean biogeochemical model (under refinement) and (c) 
state-of-the-art marine ecological models incorporating ocean 
circulation and spatially explicit processes.
    Comprehensive Earth-ecosystems models have a wide range of 
applicability for managers of marine ecosystems, including:

   Short term (6 months to 1 year) and medium term (2-5 year) 
        projections of the regional response of fisheries and protected 
        species to climate change

   Seasonal-interannual prediction of the abundance and 
        distribution of marine populations;

   Seasonal forecasting of coral bleaching potential and 
        assessment of the long-term impact of climate variability and 
        change on coral bleaching frequency;

   Assessments of the health of coastal ecosystems under the 
        stress of pollution and runoff;

   Predictions of harmful algal blooms and eutrophication 

   Identification of impact of climate change on species 

   Analysis relating to land use practices and climate;

   Design of marine protected areas and other management 

   Predictions of pollution transport and effects on human 
        health; and

   Understanding seasonal patterns of plant reproduction and 
        animal migration.

    In order to develop these integrated regional and global models of 
ecosystem response, we face a number of technical challenges. 
Additional research to provide the information needed to understand the 
underlying processes linking climate change to the response of living 
marine resources is critical. Many of the examples of ecological 
response cited above are based on statistical correlations of time 
series of environmental data rather than a fundamental understanding of 
the complex relationships responsible for the observed phenomena. 
Predictive models must take such complex dynamics into account. 
Expanded ecosystem research capabilities will be required to assess 
these critical links. At the same time, expanded modeling capabilities 
will require more comprehensive physical observations and related 
routine monitoring data than we have the capability to deploy today.
Importance of the Integrated Ocean Observing System
    NOAA has a large, broad-scale and robust system of oceanographic, 
climate, and ecosystem measurement stations throughout the U.S. EEZ and 
the world. To make data from these systems available to climate and 
ecosystem scientists both within the U.S. and globally, NOAA is working 
with other Federal agencies and academic and State partners to build 
the U.S. Integrated Ocean Observing System (IOOS). IOOS, when fully 
integrated, will provide more complete and improved access to 
observations of the oceans, including ecological and physical 
parameters linked to climate variability and change and requisite 
social and economic information, to serve multiple societal goals. IOOS 
will support regional climatologies and will provide information 
necessary to model climate impacts on ecosystems at appropriate global, 
regional, and local scales. Full development of IOOS is a high priority 
in understanding climate effects on U.S. marine ecosystems, and 
contributes to U.S. support of the Global Earth Observing System of 
Systems (GEOSS).
Management of Living Marine Resources using Ecosystems Approaches
    Our current understanding of climate impacts on marine ecosystems 
points to the critical need to employ ecosystem-based approaches to 
monitoring, assessing, and managing living marine resources. Climate 
change is only one of a complex set of factors (both human-induced and 
naturally-occurring), that influence living marine resources. These 
include harvesting policies for fisheries, protected species recovery 
policies, and management of increasingly complex uses of the coastal 
zone for a variety of other societal needs. Effective management of 
resources in this complex environment means we will have to balance 
many competing and simultaneous objectives. NOAA is committed to 
advancing an ecosystem approach to its many stewardship 
responsibilities as a way forward in striking this balance. NOAA 
defines an ecosystem approach to managing living resources is one that 
is geographically specified, collaborative, adaptive, accounts for the 
broad scope of ecosystem knowledge and uncertainties, considers 
multiple factors affecting resources, is incremental in approach, and 
balances diverse societal objectives. Incorporating the effects of 
climate change into the conservation of living marine resources is one 
of the Nation's greatest and most critical challenges facing ocean 
ecosystems management.
    Thank you Mr. Chairman, I would be pleased to answer any questions 
you or the other Committee members may have.
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    Senator Vitter. Thank you very much, Doctor.
    We also have, as I said, Dr. Armstrong. Thank you for being 
here, as well, Doctor, and please proceed with your testimony.


    Dr. Armstrong. OK. Mr. Chairman and members of the 
Subcommittee, thank you for the opportunity to participate in 
today's hearing.
    I am Dr. Thomas Armstrong, Program Coordinator for the 
Earth Surface Dynamics Program at the U.S. Geological Survey. I 
also represent USGS in the Department of the Interior with the 
U.S. Climate Change Science Program and the Climate Change 
Working Group of the Arctic Monitoring and Assessment Program.
    The USGS strives to understand how the Earth works and to 
anticipate changes in how the Earth functions. To accomplish 
this, USGS science aims to understand the interrelationships 
amongst Earth's surface processes, ecological systems, and 
human activities. This includes understanding current changes 
in the context of prehistoric and recent Earth processes, 
distinguishing between natural and human-induced changes, and 
recognizing ecological and physical responses to changes in 
    The scientific community is largely in agreement that human 
activity in the 20th and 21st centuries has enhanced greenhouse 
gas concentrations in the atmosphere and has affected global 
temperature and climate. But climate change is also a natural, 
continuous, inevitable Earth process that has occurred 
throughout Earth's history. Natural climate change is 
influenced by many forces, one of which is concentration of 
both naturally-emitted and human-induced greenhouse gases into 
the atmosphere. In fact, natural climate change has occurred on 
a regular basis on this planet for millions of years.
    Paleoclimate research conducted at USGS and elsewhere has 
shown that the Earth has experienced several episodes of global 
warming in the last 800,000 years, during which air 
temperatures and levels of CO2 increased in ways 
comparable to present changes. By studying various parameters 
or proxies in the prehistoric record, such as tree rings, ice 
cores, and fossil records, scientists at USGS and elsewhere 
have developed a detailed record of prehistoric climate change, 
including changes in temperature and atmospheric CO2 
concentrations over the last several hundred-thousand years. 
This record shows that natural climate change is generally 
cyclical in nature, with 40,000- to 50,000-year-long cycles of 
global cooling and glaciation, punctuated by, typically, 
10,000-to 15,000-year-long cycles of global warming and 
deglaciation, which are often called interglacial periods.
    The general consensus among climate scientists is that we 
are now in an interglacial period with related global warming.
    One of the major challenges facing the climate science 
community today is distinguishing natural change from change 
imposed upon the natural system through human activities. 
Although the prehistoric climate record includes temperature 
conditions comparable to those today, ice core records and 
other recent scientific findings show that the current 
concentrations of CO2 in the atmosphere are now 
higher than at any time in human existence or in the 
prehistoric record. This trend suggests a significant excursion 
from the prehistoric natural climate record that may lead to 
unprecedented climatic conditions in the future. A better 
understanding of the causes of this change is necessary before 
scientists can differentiate between the natural and human-
influenced components of present climate change, as well as the 
potential influence of human activities on future global 
    Understanding the processes and distinguishing natural 
variability from human-influenced change is just the first step 
toward success in the field of climate change. Equally 
important is effectively communicating climate science to the 
rest of the world.
    Scientists must relay the information, analyses, and, more 
importantly, conclusions to policymakers, resource managers, 
and the general public in ways that are both easy to understand 
and useful. In addition, and very important, scientific 
findings related to climate change must be delivered in a 
timely manner so that decisionmakers will be informed by the 
most relevant, up-to-date, objective information possible. 
Furthermore, scientists must provide this information with very 
accurate estimates of uncertainty so that conclusions and 
recommendations drawn from scientific studies can be properly 
    The climate science community continues to struggle with 
development of a consensus on the specifics of the long-term 
climate future for our planet, but, as we continue to conduct 
well-planned science to make progress on defining natural 
climate change and to better distinguish natural from human-
influenced climate change, we will gain a fuller and more 
useful understanding of how climate has changed in the past, 
how it occurs today, and how it may occur in the future under 
different sets of human-influenced scenarios.
    Thank you, Mr. Chairman, for the opportunity to present 
this testimony, and I will be pleased to answer any questions 
you and the other Members of the Subcommittee may have.
    [The prepared statement of Dr. Armstrong follows:]

  Prepared Statement of Dr. Thomas R. Armstrong, Program Coordinator, 
 Earth Surface Dynamics Program, U.S. Geological Survey, Department of 
                              the Interior
    Mr. Chairman and Members of the Subcommittee, thank you for the 
opportunity to participate in this hearing on climate change and its 
effects on terrestrial and marine systems. My name is Tom Armstrong, 
and I am the Program Coordinator for the Earth Surface Dynamics Program 
at the U.S. Geological Survey (USGS). I also represent USGS and the 
Department of the Interior as a member of the U.S. Climate Change 
Science Program and the Climate Change Working Group of the Arctic 
Monitoring and Assessment Program.
    The USGS strives to understand how the Earth works and to 
anticipate changes in how the Earth functions. To accomplish this, USGS 
science aims to understand the interrelationships among Earth surface 
processes, ecological systems, and human activities. This includes 
understanding current changes in the context of pre-historic and recent 
Earth processes, distinguishing between natural and human-influenced 
changes, and recognizing ecological and physical responses to changes 
in climate.
    We conduct scientific research in order to understand the likely 
consequences of climate change, especially by studying how climate has 
changed in the past and using the past to forecast responses to 
shifting climate conditions in the future. My testimony today will 
address three major sets of challenges:

        1. Distinguishing natural from human-influenced climate change;

        2. Understanding ecological and physical responses to climate 
        change, and predicting the related impacts of these responses 
        on climate; and

        3. Effectively conveying cutting-edge climate science to 
        policy-makers, decision-makers, and the public.

    I will conclude my testimony with a brief discussion of the state 
of our understanding of climate science and how this provides a roadmap 
to our future understanding of long-term climate change and its impact 
on people, natural resources, and the Earth.
Distinguishing Natural from Human-influenced Climate Change
    In a statement on behalf of the Administration to the Senate in 
July, 2005, Dr. James R. Mahoney, now former Assistant Secretary of 
Commerce for Oceans and Atmosphere, and Director of the U.S. Climate 
Change Science Program, stated, ``We know that an increase in 
greenhouse gases from the use of energy from fossil fuels and other 
human activities is associated with the warming of the Earth's 
surface.'' This statement underlies the growing public debate on 
climate change: are humans and their activities the driving force 
behind global warming? The scientific community is largely in agreement 
that human activity in the 20th and 21st centuries has enhanced 
greenhouse gas concentrations in the atmosphere, and these added gases 
have an effect on global temperatures and climate. Climate change is 
also a natural, continuous, inevitable Earth process that is influenced 
by many forces, one of which is the concentration of both naturally-
emitted and human-induced greenhouse gases in the atmosphere. Many 
other forces also control climate change, including cyclical changes in 
solar radiation, movement of the Earth's tectonic plates, oscillations 
in ocean temperatures and ocean currents, and the positions and 
magnitudes of meteorological entities such as high, low, and convergent 
zones. In fact, natural climate change has occurred on a regular basis 
on this planet for at least the last 800,000 years and possibly much 
longer. Paleoclimate research has shown that the Earth has experienced 
several episodes of global warming in this timeframe during which air 
temperatures and levels of CO2 increased in ways comparable 
to the present day changes, although the ice record indicates that the 
current concentrations of CO2 in the atmosphere are 
unprecedented during human existence. Understanding the science of 
natural variability in climate is essential to the formation of 
effective policy regarding the mitigation of or adaptation to climate 
change, both human and natural.
    One of the major challenges facing the climate science community is 
distinguishing natural climate change from that imposed upon the 
natural system through human activities. This science must also develop 
an effective understanding of the consequences of the human-induced 
component. The science we conduct in order to understand both the human 
component of climate change and its potential impacts on the natural 
climate system is known as climatology; paleoclimatology looks into the 
prehistoric past of the Earth in order to determine how climate change 
occurred prior to human activity. Through paleoclimate studies, 
scientists have been able to determine that climate changes naturally, 
and that there indeed are natural climate cycles that have occurred 
regularly, and in a predictable fashion, over at least the last 800,000 
years of Earth history.
    By studying various parameters, or proxies, in the prehistoric 
record, such as tree-rings, ice-cores, and fossil pollen records, 
scientists at USGS and elsewhere have been able to develop a detailed 
record of climate change, including changes in temperature and 
atmospheric CO2 concentrations over the last several hundred 
thousand years (Figure 1). This record shows that natural climate 
change predates human influence and is generally cyclical in nature, 
with long-term periods of global cooling and glaciation (40,000 to 
50,000) years long, punctuated by shorter-term periods of global 
warming and deglaciation (10,000 to 15,000 years in duration). The 
general consensus among climate scientists is that we are within a new 
interglacial period with related global warming.

Ecological and Physical Responses to Climate Change
    A second set of very important challenges relates to developing a 
better understanding of how the Earth and its physical and biological 
processes respond to climate change over the short-term and well into 
the Earth's future. Scientific research conducted over the past several 
decades reveals that climatic changes are part of a larger interactive 
system of changes in ecosystems, oceans, glaciers, atmospheric 
chemistry, and many other components. The geologic record provides 
information on how this complex system has operated over time and clues 
to the potential causes of change. By looking back into the Earth's 
geologic record, scientists have been able to determine how ecological 
and physical systems and processes change, adapt, or terminate as 
climate changes; and how these responses can alter climate (known as a 
feedback mechanism). Many of these climate changes are gradual and 
continuous, with ecological and physical responses occurring over 
hundreds or thousands of years. Some of these climate changes are 
abrupt, spanning decades, with the resulting ecological and physical 
changes being short-lived but very dramatic.
    Some examples of responses and feedbacks to climate change include:

   The temperature of the United States has increased by an 
        average of less than 1 degree Celsius during the past 56 years, 
        with much variation among regions. For example, Alaska has 
        experienced an average warming of 4 degrees since 1950, more 
        than 4 times the U.S. average of 1 degree.

   The higher the latitude, the greater the increase in 
        temperature. Of particular concern are the rapid changes 
        occurring in northern latitudes, where temperature changes have 
        been greater than elsewhere on the globe. Permafrost is thawing 
        and has the potential of releasing significant amounts of 
        carbon dioxide to the atmosphere and nutrients to the coastal 
        ocean. Decreasing ice cover is exposing coastlines to rapid 
        erosion and the Arctic Ocean to accelerated warming. The USGS 
        and the U.S. Forest Service are initiating a multi-agency, 
        multi-disciplinary research and monitoring effort to track and 
        understand these changes in the Yukon River Basin in Alaska and 
        northwest Canada. The Yukon Basin will serve as a benchmark 
        landscape for interpreting and responding to rapid climatic, 
        hydrologic, and ecological changes occurring in Northern 

   Decreased cloud cover in the northern latitudes related to 
        climate change correlates to decreased snow levels, less solar 
        reflection, and thus greater melting of snow, glacial ice and 
        permafrost. This creates an additional feedback mechanism where 
        more melting leads to greater atmospheric water vapor, which in 
        turn leads to a warmer atmosphere.

   Over the last 50 years, climate change in the northeast 
        (Maine and New Hampshire) and mountain-west (Washington and 
        Oregon) of the United States has led to between 8 and 17 
        percent declines in annual winter snow pack. The physical 
        response to this decline includes decreased recharge of the 
        ground-water systems, decreases in surface-water flows, 
        increased stress to public water systems, changes in the timing 
        of river ice-outs, and significant impacts on the spawning 
        environments for fish such as Pacific and Atlantic salmon.

The Effective Conveyance of Climate Science to Policy-makers, Decision-
        makers, and the Public
    Scientists must relay relevant information, analyses, and 
conclusions to policymakers, resource managers, and the general public 
as a whole. Besides global warming, other ecological and physical 
consequences of climate change may include strong storms, sea-level 
rise, droughts and floods. If scientists can better inform decision-
makers about what to expect from climate change, this will effectively 
enhance the development of short- and long-term strategies for 
protecting the public welfare and maintaining healthy and viable 
ecosystems and natural resources. For instance, studies conducted by 
USGS and others are showing that sea-level rise will continue to impact 
coastal zones throughout the world. Present and future resource 
managers will need to take into consideration this scientific 
conclusion when developing an adaptive management strategy for 
restoration and long-term stewardship of land, water, and biological 
    Scientific findings related to climate change must be delivered in 
a timely manner so that decision-makers are informed by the most 
relevant, up to date, objective information possible. Furthermore, 
scientists must provide this information with very accurate estimates 
of uncertainty so that conclusions and recommendations drawn from 
scientific studies can be properly evaluated. The U.S. Climate Change 
Science Program, of which USGS and the Department of the Interior are 
members, is actively involved in developing a more effective decision 
support strategy for all interested stakeholders.
The Future of Climate Change
    Understanding the paleoclimate history--where we look at climate 
information well beyond the 50 to 100 year instrumental record--is 
important because it provides us a natural climate baseline from which 
to work. The instrumental record provides us only a momentary glimpse 
of the entire picture of past and future climate change. We need to 
understand what has happened in the past in order to forecast future 
short- and long-term climate trends. Once the baseline has been 
established we can then begin to distinguish the human-induced factors 
that must be considered. This information then allows us to validate 
model predictions of past climate change and use that information to 
develop better-constrained models to forecast the effects of future 
climate change, and related ecological and physical responses and 
    For all of the information we have gathered, and for all of the 
understanding of climate change that we have developed, the climate 
science community continues to strive toward development of a consensus 
on the long-term climate future for our planet. Given our current 
scientific understanding of climate change, the following are areas in 
which USGS science can make a valuable contribution:

   Determining the baseline physical, chemical, and ecological 
        conditions of the Arctic and Subarctic. Without new baseline 
        data and monitoring infrastructure, our ability to determine 
        what changes are occurring in northern latitudes, and our 
        capacity to help society develop cost-effective adaptations to 
        those changes, may be greatly diminished.

   Developing decision support systems for the impact of sea-
        level rise. Current research concludes that sea level rise will 
        continue. Since sea-level rise is already having impacts on 
        some ecosystems and human communities, decision support systems 
        will be critical tools for planners to anticipate levee 
        construction or relocation of shoreline infrastructure.

   Focusing attention on the potential changes in the most 
        vulnerable regions and systems (e.g., polar regions, coastal 
        zones, and the tropics), and assessing regional impacts of 
        long-term climate change.

   There might be surprises: critical thresholds in Earth and 
        biological systems may be abruptly reached that have long-term 
        or even permanent consequences.

   Adaptation strategies can minimize negative impacts of 
        natural climate change, as well as the impacts of human-induced 
        climate change; mitigation may work to quell human-induced 
        climate change and variability.

   Although possibly successful, mitigation of natural changes 
        may very likely lead to unforeseen additional problems unless 
        the system under study is extremely well understood.

    Thank you, Mr. Chairman, for the opportunity to present this 
testimony. I will be pleased to answer questions you and other Members 
of the Subcommittee might have.

    Senator Vitter. Thank you both very much.
    I'll open it up with questions, and pose this question to 
both of you. Where do 20th century measurements and trends fall 
in the very, very long-term historical record, in terms of 
previous natural historical cycles?
    Dr. Armstrong. Senator, I'll go first.
    The current conditions of temperature fit within what we 
see in terms of cycles of climate change over the last 400,000 
years. We need to look at climate both in terms of long-term 
climate change over a long-term many thousands-of-years in 
order to distinguish various long-term natural climate cycles, 
but also to distinguish those long-term cycles from human-
induced change. But temperature is a component that is on--in 
the realm of what we've seen in the prehistoric past.
    What is most unique, I think, is that the temperature is 
out of alignment with the present CO2 concentrations 
and methane concentrations that we see in the atmosphere. 
Those, according to the most recent scientific information, are 
at unprecedentedly high levels compared to the prehistoric 
    Senator Vitter. Doctor?
    Dr. Murawski. Just look at the shorter time cycle, the last 
10,000 year, since the last ice age. The current temperatures 
and current amount of precipitation is actually the highest 
levels that we've seen in the last thousand years.
    Senator Vitter. But that's sort of one cycle. I guess what 
I'm asking is, If you look at previous historical cycles, 
including peaks, is this--fall within those boundaries, or not?
    Dr. Murawski. I agree with the testimony that Dr. Armstrong 
gave, in terms of long-term cycling of----
    Senator Vitter. Right.
    Dr. Murawski.--ice ages that have come and gone.
    Senator Vitter. What would be the temperature point or line 
beyond which this current trend would clearly be moving beyond 
previous historical experience?
    Dr. Armstrong. I can get the specific information for you.
    But I can say, offhand, that we are--within the 
uncertainties that we have from the geological record, we are 
on par for being at the peaks of what we've seen in long-term 
climate cycles. We are at a peak, in terms of temperature. If 
it goes much higher than what we see today, we will be getting 
into that realm within the uncertainties of the information we 
have in the past, where temperatures will reach unprecedented 
levels. But it really--I want to stress, Senator, that it is 
the CO2 and the methane levels in the atmosphere 
that are significantly higher than what we have seen in the 
prehistoric record.
    Senator Vitter. Right. Right. But, of course, one of our 
biggest concerns about those levels is impact on temperature.
    Dr. Armstrong. Correct.
    Senator Vitter. And so, that's why I'm----
    Dr. Armstrong. That is correct.
    Senator Vitter.--asking about impact on temperature.
    Dr. Armstrong. Right. And that is something that USGS 
science looks a lot at the past record, and we see that there 
is a coincidence between changes in greenhouses gases naturally 
emitted, obviously, in the prehistoric record, greenhouse gas 
concentrations, and temperature changes. They do mimic each 
other. What--if we look at the present scientific literature, 
the most recent information from ice core records and other 
information, there seems to be a disconnect now between levels 
of greenhouse gases, which are going up, compared to what we 
see with temperature.
    Senator Vitter. OK. Also, another pretty broad question for 
both of you. What's each of your opinions regarding the state 
of science, in terms of climate models? Obviously, in terms of 
your projection to the future and impacts that it could have on 
the environment and animals, as well as human populations, we 
need to depend on certain models and predictions. What's your 
assessment of the current state of the accuracy and fine-tuning 
of those models?
    Dr. Murawski. We see a convergence of many global climate-
change models that are being run now, and we see a general 
convergence in the results. In fact, there was a paper 
published in Nature a couple of weeks ago that looked at the 
various model runs and looked at their assumptions. And we do 
seem to be closing in on the general range of temperature 
increases that'll be there.
    That being said, we know that we have to do more, in terms 
of the modeling, in terms of understanding regional impacts, 
because that's what's so important for the ecosystems, both 
terrestrial and in the ocean, how the regional climatologies 
will influence what goes on, because even the global models 
that we have now, are indicating some places will be wetter and 
cooler under a general rise in Earth's temperature. And so, we 
need to understand and step those models down into the regional 
size to understand the regional ecosystem impacts better.
    Senator Vitter. And I assume--Doctor, before you answer--I 
assume part of this analysis of modeling is how a model 
predicts past behavior. And how do they? How do the best models 
we have developed to date compare, in terms of predicting past 
    Dr. Murawski. Well, I'm not a climatologist, so I'll pass 
on that one. We can certainly get that information back to you.
    Senator Vitter. OK.
    Dr. Armstrong. Yes, I would actually like to go back to 
what Dr. Murawski was saying about the articles in Nature by 
Dr. Overpeck and other scientists. There are several in the 
journal, Nature and Science.
    One of the global circulation models that was used in this 
paper was doing just what you asked, Senator, and that was 
looking--using the current model framework and incorporating 
the geologic record, the prehistoric record into the model, and 
found that, as they put in various parameters from the past 
into the framework of this model, including starting conditions 
and intermediate and long-term conditions, they were able to 
mimic very well the proxy record or the conditions that the--
you would predict, that we know occurred in the past, and then 
take that, in turn, and look toward the future. And I would say 
that's one of the things at USGS that we--I would have to say 
are--have been critical of in the past with research, is that 
some of the research hasn't really looked at the natural 
variability of systems as effectively as it needed to. And I 
think these papers, by Dr. Overpeck and others, are a real 
significant breakthrough in the use of the paleorecord in order 
to better understand or calibrate to the past to predict into 
the future.
    Senator Vitter. OK.
    Dr. Murawski, in your testimony you mentioned, somewhat in 
passing, that subsidence in Louisiana, which I'm obviously very 
interested in, is attributable to hydrocarbon recovery in 
coastal areas. I've talked to some experts down there who also 
say that there is long-term natural subsidence unrelated to 
more recent activity. Would you like to comment on how you 
think those two factors contribute, in terms of subsidence in 
coastal Louisiana, in particular?
    Dr. Murawski. Sure. There are a lot of factors that are 
influencing the rate of sea-level rise there. And, of course, 
coastal Louisiana is the hotspot for sea-level rise throughout 
the country. Obviously, you've got the issues of the reduction 
in sediment coming down the Mississippi and other major rivers, 
which are contributing to the marshlands being reduced in size. 
You've got all sorts of exploration and production activities 
that are creating voids there, that contribute to subsidence. 
And then, you've got general sea-level rise. And so, it's the 
mix of those three factors that's important. And, of course, 
we're trying to mitigate sea-level rise issues in the coastal 
marshes down there, because they're so important to the marine 
fisheries of the Gulf area, because most of the species there 
are estuarine dependent. That means their juvenile nursery 
areas are in those marshes, and they're so important.
    Senator Vitter. In terms of the relative significance of 
the various factors, do you think there is a scientific 
consensus about it? Because obviously that drives, in part, 
what we might do to stop it or mitigate it.
    Dr. Murawski. Well, there has been a lot of work in trying 
to look at those relative factors, and they're probably playing 
out differently in different locations. Obviously, the 
reduction in sediment load in the Mississippi over the last 
century has been very significant, in terms of that, but, of 
course, you know, in various places the balance of those 
factors may play out differently, just because of the nature of 
those activities, the very local, you know, exploration 
activities, et cetera.
    Senator Vitter. OK, thank you.
    Chairman Stevens?
    The Chairman. In terms of looking at the long, long, long 
history of the world, what is the--sort of, the period of time 
that the cycles have taken place? One of you go back 30- to 
40,000 years. How far back do you go, in terms of your 
    Dr. Armstrong. Well, the science that I was referring to, 
Senator, we were looking back over the geologic record 400- to 
800,000 years, and obviously the farther back you go, the less 
perfect the record, the lower our resolution, and the higher 
our uncertainty, which is important to clearly define.
    There are different cycles related to different things--
orbital forcing, solar insulation. These cycles occur on time 
periods of cycles of 100,000 years, 40,000 years, 17,000 years, 
possibly 9,000 years. But these cycles combine to present what 
is a very regular cyclical pattern over that long-term 
geological record.
    The Chairman. If I understood Dr. Armstrong, if you compare 
the current period to the distant past, there still are some 
cycles where the highs and lows and the differences would be 
similar to what we're--we've gone through in the past. Is that 
    Dr. Armstrong. That's correct. That's in my written 
testimony, as well, at figure 1. Absolutely so.
    The Chairman. So, we could--then we could be either at the 
top of the cycle and going up, or we could be at the top of the 
cycle and starting to turn down.
    Dr. Armstrong. The--one of the problems you'll see, even in 
figure 1 of my written testimony, is that if we try to 
telescope too much the instrumental record, be it 40 years or 
100 years, we're looking at a very short period of time in that 
long-term climate cycle. It is not much information, in terms 
of the long period of time. And without that geologic--that 
paleoclimate information, we really can't deduce the long-term 
cycle. That's why the ice core analyses, both from west 
Antarctica and Greenland, have been so invaluable to us in 
understanding long-term climate cycles, because those cycles 
are much, much longer than the instrumental record itself.
    The Chairman. All right. As you say--if your number-one 
challenge is to distinguish natural from human-influenced 
climate change, right?
    Dr. Armstrong. I believe that is one of our major 
challenges, yes.
    The Chairman. What do we need to do to do that job better?
    Dr. Armstrong. I think one of the things that we've been 
trying to do at the USGS--and I know that other people at NOAA, 
with their group on paleoclimate, and academia, are trying to 
develop better proxies or better indicators of past climate 
conditions, and certainly a better handle on age uncertainties 
of the climate record itself, so that we can have a higher 
resolved, more accurate understanding of when changes occurred, 
exactly, or as close to exactly we can in the geologic record, 
and what were the exact conditions that occurred, both in terms 
of temperature or gas concentrations or other valuable pieces 
of information, including ecological responses to climate 
change over the geologic record.
    The Chairman. Well, Dr. Akasofu's volcano observatory can 
give us a prediction of how soon a volcano may erupt, but we 
can't get a prediction over a period of years ahead how often 
is that going to happen. Those are natural emissions, right? 
Now, do we need any more measurements to determine how much is 
natural and how much is manmade on--from the natural side?
    Dr. Armstrong. My opinion is, yes, we do. We need more 
science that can distinguish--first, truly understand natural 
variability, natural climate change, because that baseline is 
not static, it is not flat, it is changing. It's constantly 
changing. It may not change a lot on a daily basis or over 100 
years, but at times it can be abrupt or it can occur 
dramatically over 1,000 years. Having more information on that 
natural baseline and how it changes and will change over time 
is critical to understanding what the additive effects of human 
activities are on global climate, and as Dr. Murawski said, on 
regional climate, as well.
    The Chairman. All right. Dr. Murawski, you're more 
connected with the ocean side of this, right?
    Dr. Murawski. Right.
    The Chairman. Which is two-thirds of the world's surface, 
    Dr. Murawski. Right.
    The Chairman. Do you really think you have the ability to 
measure that two-thirds today?
    Dr. Murawski. Well, one of our proposals, obviously, is to 
try to improve the observing that we're doing in the ocean side 
through the Integrated Ocean Observing System and other things. 
We're trying to take more and more physical measurements and 
correlate them with a more dense biological observing system, 
as well. I mean, we're trying to measure things like changes in 
walrus distribution and whale distribution in the Bering Sea, 
along with the fish species, crab species, and other things. 
It's a----
    The Chairman. I'm a fisherman. I think the whales and 
mammals go where the fish are, just like we do. But I'll put 
that aside.
    What do you think you need, in terms of ability to measure 
the oceans, that you don't have?
    Dr. Murawski. Well, we need a lot more dense observation 
network, in terms of physical measurements--basic buoys, the 
sea surface temperatures from satellites. Next generation, we 
need the basic tools to measure the biological processes that 
we're looking at. They need to be more dense. They need to be 
distributed around the coasts. We have a system that's about 50 
percent built out at this point, in terms of measuring the 
various parameters, both on the physical----
    The Chairman. Right.
    Dr. Murawski.--side and----
    The Chairman. Last question, I'll--I've got a lot more 
questions, but I'll only ask one more. I'm sure you're familiar 
with what Dr. Sylvia Earl is doing with her submersibles. Are 
we learning anything from those submersibles, in terms of 
what's happening in the deep sea, as compared to what's 
happening on the surface?
    Dr. Murawski. Well, in terms of the deep sea, obviously, 
you know, this is one of the most unexplored areas on the 
planet. Now, we have an ocean exploration project in NOAA that 
we've been trying to nip away at, understanding deep coral 
reefs and other things. We're learning that, there's a lot more 
biological diversity down there than we have anticipated. For 
example, the coral gardens off Alaska, in the deep water, were 
unknown to science until we started poking around in the deep 
water. We definitely need a research program that looks not 
only at the coastal ocean, but the deeper ocean, as well.
    The Chairman. Well, I've just--I lie a little, that that 
was my last question. What's the impact of changes in the deep 
sea, as far as human experience, compared to that on the 
surface? Is there anything going on down there we should--we 
really should be excited about?
    Dr. Murawski. Well, one of the things that we need to be 
careful about is this new discovery of these deep coral gardens 
that we see in the deep oceans. Those deep cold-water corals 
are at risk to increasing acidification of the ocean, because 
those corals are formed by the accumulation of calcium 
carbonate. And if, in fact, the calcium carbonate budget of the 
deep ocean is going to decline, particularly in the polar 
areas, which some of the projections indicate, then they could 
be at risk for long-term climate change.
    The Chairman. Well, I have a bill to authorize further 
ocean exploration to deal with that kind of research. 
Unfortunately, we have a Senator that doesn't want anything 
else new authorized, thinks there are too many programs already 
authorized. So, we'll probably have to wait until we solve that 
    Thank you very much, Senator.
    Senator Vitter. Thank you, Mr. Chairman.
    Senator Lautenberg?
    Senator Lautenberg. Thanks, Mr. Chairman.
    I'm sorry I didn't hear all of the testimony that each of 
you gave, but I've read through, and I would just like to ask 
you, What do each of you think about the widest differences of 
view for those who don't see any real alarm out there, as 
opposed to those who are--who feel that this is a matter of 
great urgency? Are we now being forced to take actions, if I 
may use the expression, before it's too late, in terms of the 
climate change in--that we're seeing?
    Dr. Murawski. As I said in my verbal testimony--and I'm 
sorry you weren't here--these factors of increasing 
acidification of the ocean, sea-level rise, changes in the 
distribution of animals are all sources of concern that we have 
to have, in terms of the ecosystem effects of climate change.
    Senator Lautenberg. Serious concern.
    Dr. Murawski. Certainly.
    Senator Lautenberg. Urgent.
    Dr. Murawski. The urgency of the issue depends on the 
issue, in terms of where we are.
    Senator Lautenberg. Well----
    Dr. Murawski. We have a number of issues----
    Senator Lautenberg.--because we have a debate, an honest 
debate among us in the Senate, those who think that, as I said 
in my opening remarks, that we're going to endanger our 
economy. And I have a comma, and that is, ``if we're still 
alive after that.'' And so, you know, the--I'm, kind of, one of 
those who could be called an alarmist. The principal reason for 
that is, I have ten grandchildren. They're very young. And we 
love the outdoors in my family. And it's not simply going for a 
swim or fishing. I have a grandchild who has asthma fairly 
severely, and we have to be very careful when he over-exercises 
or what have you. And now, is the world that we're looking at 
going to endanger his health even more? We see a--substantial 
rises in the number of juvenile asthmatics and other autoimmune 
diseases that are connected to the respiratory well-being. Is 
that--might we expect a turnaround in things and suddenly see 
the air start to clear up? Or will we be looking at face masks 
along the way?
    Dr. Murawski. Well, obviously we're concerned about issues 
like oceans and human health. That's a new, emerging set of 
sciences that we're trying to understand the ramifications of 
how changes in ocean systems influence the prevalence of 
disease, the relationship of atmospheric issues to ocean 
changes, et cetera. And those are obviously areas of emerging 
science and emerging interest, in terms of you and others.
    Senator Lautenberg. Dr. Armstrong, do you have any comments 
about my question?
    Dr. Armstrong. Yes, sir. And I am--I'm sorry you missed my 
oral--part of my oral testimony----
    Senator Lautenberg. I am, too.
    Dr. Armstrong.--as well. I think the issue that you're 
really getting at here, first and foremost, is the disagreement 
on how much of what we're seeing today--and Senator Stevens 
said it, we've heard it in testimony--I don't think there's 
much disagreement that there is ecological and physical 
response to global warming, to climate change. There are 
responses. There always have been responses. The question 
becomes, What is natural change and response, and what is 
human-induced change? And I think the question really becomes, 
Can we distinguish between natural climate change or climate 
variability and that influenced or induced by human activity? 
And that is something that I think we still have a fair amount 
of disagreement of, is, How much of each of those components 
plays into what we see today? But we recognize that both have a 
very large role, and we need more science to really help 
distinguish that. But, beyond that, sir, I'd have to say that, 
as a scientist, it isn't my job to define urgency or what 
mitigation or what policy needs to occur; rather, provide you 
with the science you need in order to--you and others--to make 
those decisions.
    Senator Lautenberg. Well, if we know that human activity 
causes a significant part of the changing climate that we see, 
are we wise to, instead of trying to balance the scales and see 
which comes from where, to get on with that part that we can 
deal with and accept some of the natural responses that we get? 
Shouldn't we focus on that part, that we know the reduction of 
the effects of the human production of problems to the 
climate--wouldn't it be a good idea to get going on those 
things and----
    Dr. Armstrong. I agree that in order to mitigate, you need 
to understand what you can mitigate. And science can help 
provide the information you need in order to understand what it 
is that can be mitigated and what are the things that may have 
to--we may need to adapt to. But in terms of what those are, I 
believe that we just need to provide you with the best, most 
relevant science to make those decisions.
    Senator Lautenberg. Well, if there's a fire at home, and 
you know that it's going to engulf you, and--what you do is, 
you immediately respond to getting the fire out, and not try to 
just run through the house and find the coolest place. And, you 
know, when I see what I think are the irrefutable results of 
life as we know it, is that when we look at places like Glacier 
National Park and we see that it won't be too long before there 
are no more glaciers in Glacier National, or if we see 
Kilimanjaro, if we see places in Greenland where shelves of ice 
are floating away and leaving something different--and then 
Senator Stevens--there are few who are better naturalists than 
Senator Stevens, but Alaska is a place with its abundant 
beauty, but also there are obviously problems arising. And when 
I see what's happened--there was a--and I'm not sure which of 
the programs I was watching--the polar bears, and how their 
reductions in weight is endangering their existence, and cubs 
are born less--in smaller numbers than they used to be--
commonly two or three at a time, now it's barely one at a time, 
and the reproduction rate is substantially reduced. When I see 
things like that, it--I must confess you, it scares me.
    Now, am I correct in saying of the hottest years on record, 
19 occurred in the 1980s, or later, and three of the warmest 
years on record, average global temperatures, in 1998, 2002, 
and 2005? Stop me if I'm incorrect with any of these. 2005 was 
the highest annual average temperature worldwide since 
instruments--instrumental recordings began, in the late 1800s. 
To your knowledge, are those statements correct?
    Dr. Murawski. I believe they're accurate.
    Dr. Armstrong. Yes.
    Senator Lautenberg. Don't know?
    Dr. Armstrong. I believe they're accurate.
    Senator Lautenberg. They're accurate. Did you say you 
weren't sure----
    Dr. Armstrong. I said I believe they're accurate.
    Senator Lautenberg. Oh, OK. Well, the--that tells me that 
we've got to get going.
    I would ask if any of you have--it's--Mr. Chairman, you've 
picked an interesting subject on the--it's one that should 
absorb even more attention than we're giving it--have you--
either of you been approached by NOAA scientists who are 
concerned that we're not doing enough to address the threat of 
global warming?
    Dr. Murawski. I'll take that issue. Obviously, you know, we 
have 5,000 scientists in NOAA, and we give scientific opinions 
on a lot of different issues. And we have a lot of intense 
debate about these issues, in terms of what we're trying to 
deal with. Admiral Lautenbacher, who runs the agency, has 
expressed to all the staff the importance of having open 
debate, in terms of these issues of policy. Our corporate 
culture is, trying to make sure that the science is available. 
We have an interest in making sure that our science is peer-
reviewed. And so, once it's peer-reviewed, it's generally 
available in the public. And, you know, we publish that 
science, and we make it widely available within the climate-
change science program and elsewhere. And so, that's our 
corporate policy, in terms of dealing with the science that we 
    Senator Lautenberg. Dr. Armstrong, have you been approached 
by anybody from the USGS registering alarm at the pace of our 
response to climate change?
    Dr. Armstrong. In terms of the pace of conducting our 
    Senator Lautenberg. Yes.
    Dr. Armstrong. No, sir, I have not.
    Senator Lautenberg. Oh, everybody--that--they think that 
we're moving at the right pace, investing enough resources in 
doing that, is that--is that your view?
    Dr. Armstrong. I--the scientists who I personally fund and 
am responsible for, I believe--we have not had an open 
discussion about that, but I can say that they feel that 
they're adequately funded to do the work that they have at 
hand, yes, sir.
    Senator Lautenberg. Dr. Murawski?
    Dr. Murawski. I think we have a fair difference of opinion 
in our agency, as any individual science would have a 
difference of opinion about their research and the importance 
of their research. And, obviously, we have to balance what we 
can afford with what Congress gives us to do our work.
    Senator Lautenberg. Just one last thing, Mr. Chairman.
    Do we have obvious examples--and you may have had this in 
your testimony--commercially significant fish and shellfish, 
their responses to acidification--are these species at risk as 
a result of the changing acid levels in ocean waters?
    Dr. Murawski. Well, it's interesting, because we had a 
similar event about 55 million years ago, in terms of the 
rising acidification----
    Senator Lautenberg. I know I'm old, but I don't remember 
    Dr. Murawski. Neither do I. And what we saw was rapid loss 
of species of plankton that are the base of the food chain. And 
so, we're concerned that as acidification rises, that we will 
see not only issues with various plankton species, which 
support the food web, but also the deep corals, which are 
potentially at risk, as well.
    Senator Lautenberg. Thanks, Mr. Chairman.
    The Chairman. Could I just----
    Senator Vitter. Sure. Mr. Chairman?
    The Chairman. I don't want to be obtuse, but, Doctor, I had 
a briefing from the BLM that located a site in northern Alaska 
where there is a promontory that they decided was--I'm sure you 
know about it, Dr. Armstrong--a watching place for hunters who 
used to hunt dinosaurs----
    Dr. Armstrong. Yes.
    The Chairman.--and such animals. Now, I don't want to 
offend you, but what if, at that period, someone had gotten 
alarmed about the rate of change and tried to disturb the 
natural occurrence of change? Are we in a similar position?
    Dr. Armstrong. Senator, I think that, as I said, if natural 
change is inevitable, and it's part of just the Earth's engine 
and its processes, then we do need to understand what it is 
that we are dealing with. We need to understand, as best we 
can, what is natural change, versus human-induced change, 
because if we do try to mitigate natural issues, natural change 
itself, if we do not understand, in totality, the system in 
which that natural change is occurring, there may be unforeseen 
complications or other problems that occur due to the 
mitigation itself.
    So, my point is not to say that we should not mitigate. My 
point is not to say we shouldn't adapt. My point is simply that 
the science needs to inform you as to our best understanding 
today what is natural change, what do we believe is--based on 
the scientific information with the degrees of uncertainty we 
have today, what is the human-influenced part of climate 
change, so that the people that are really the ones responsible 
for mitigation and policy on adaptation can make those 
decisions in an informed environment.
    The Chairman. Well, thank you. That's my hope, that we'll 
concentrate not just on the change that's caused by man, but 
concentrate on trying to understand how much of it is natural.
    Dr. Murawski. Yes, I'd like to comment on that. I think 
we're already starting to see some of our public resource 
agencies stepping out on this and trying to accommodate, you 
know, changes in the Earth's climate, in terms of the fishery 
management, for example. And one good example is, in the 
Pacific there is a phenomenon known as the Pacific decadal 
oscillation, which is a climatological feature that varies the 
climate between Alaska and the Pacific West Coast. The fishery 
managers there know that this happens from time to time, and 
the productivity of the stocks goes up and down when these 
cycles change. And so, what they're trying to do is put in 
polices that recognize when these cycles are changing back and 
forth, and shift the management accordingly, so that you don't 
over-harvest in times when it's poor, or you take advantage of, 
when the cycle is actually favorable.
    The Chairman. Absolutely. That's what my interest is.
    Thank you very much.
    Senator Vitter. Just final wrap-up questions.
    Dr. Armstrong, I'm really very interested in your figure 1 
in your testimony. And, looking at that, one obvious question 
that jumps out is, What might the lag time be between CO2 
rises and CH4 rises and temperature rises? Is the 
past historical record from Antarctic ice cores or anything 
else with regard to high temperature periods clear enough to 
tell us, in a pretty narrow number of years, which is what 
we're experiencing in the 20th century, what that lag might be 
so that, you know, we have some beginning of an understanding 
of whether the temperature chart is about to spike or not?
    Dr. Armstrong. Senator, I will--before I give you my 
answer, I'd like to say that I think several of the people, 
including Dr. Corell, on the second panel, are outstanding 
scientists who ask that very same question, too, and will have 
some very--a more accurate estimate for you, or a more 
insightful prediction.
    But what I will say is that there is a significant amount 
of debate in the scientific literature itself about whether or 
not the next--the current interglacial we're in now is one that 
will--is similar to the past, in terms of frequency and in 
terms of duration. There's a fair amount of debate over that. 
There are some scientists who have published recently--in the 
past 15 years, that have said that, based on predictions of 
orbital forcings and solar insulation, that we may be looking 
at a longer interglacial this time than what we've seen in the 
last 400,000 years, and that it is, in fact, a unique natural 
cycle that we're going into.
    I'm not enough of an expert on that field to give you an 
opinion on that, but I would say that that, in itself, is 
something that we need to look into more specifically, as to 
nail down just what will the next 15- to 35,000 years look like 
in terms of the natural climate change, and how will, with 
increasing greenhouse gases that I think we all agree we're 
seeing in the instrumental record--how will those impact 
temperature along with the natural cycle over the next 100,000 
or tens of thousands of years?
    Senator Vitter. What about the very narrow question I posed 
about the lag time, if any, between CO2, 
CH4, and temperature? Is the historical record, you 
know, going back a long time to previous high temperature eras, 
precise enough for us to know anything about that?
    Dr. Armstrong. I would say that it almost becomes a moot 
point, sir, because of the additive effect of the human-
influenced greenhouse gas emissions, that we need to have a 
better understanding of what the response will be to the 
combined--the additive and the cumulative--effect of natural 
and human-induced greenhouse gases. And I will defer to Dr. 
Corell on that question. I think you'll get an accurate--a 
better understanding of the answer to that question. I do not 
have estimates for you.
    Senator Vitter. OK. Well, what I'm getting at, I don't 
think is a moot point, because it basically goes to whether, at 
the end of your figure 1, we're going to experience a spike in 
temperature or not.
    Dr. Armstrong. I do not have the answer to that question. 
That--I didn't mean to infer that that--you know, your question 
was a moot----
    Senator Vitter. Right.
    Dr. Armstrong.--point. It's not. It's a very important 
point. And it really need--we need to have a better 
understanding from the people that are conducting the models 
and forecasting forward, what will be the additive effect in 
this case, in this interglacial----
    Senator Vitter. Right.
    Dr. Armstrong.--which is unique because of the human 
activity on this planet. What will be the additive effect to 
both greenhouse gas emissions for the future, and, therefore, 
the impact on temperature--global temperatures, for the near 
future and the long-term future? I do not have the answer to 
that question, sir.
    Senator Vitter. Thanks. And I'd invite, ahead of time, the 
second panel to respond to that question, too.
    And, Dr. Murawski, in the Magnuson-Stevens reauthorization, 
I've included some authority for restoration work for fish 
habitat, particularly with the hurricanes and other events in 
mind, that would go through the National Marine Fisheries 
Service, through NOAA. Do you have any comment about the 
usefulness of that sort of work?
    Dr. Murawski. Well, as you know, NOAA is involved in a 
number of activities for restoration. There is quite a vigorous 
program in Louisiana, in particular, that's--the Army Corps of 
Engineers, NOAA, USGS, and the State of Louisiana are involved 
in something called CWPPRA. And CWPPRA is quite successful. 
This is the Breaux bill. It funds about $55 million a year, in 
terms of habitat restoration. And the projects that we're 
responsible for in CWPPRA, have been quite successful. In fact, 
they negotiated the hurricanes quite well, in terms of the 
design of their properties. And we see that coastal restoration 
can work in those areas, that we can mitigate against sea-level 
loss and loss of those marshes by projects that go through that 
sort of process, where we get the best projects, and the 
highest priority ones.
    Senator Vitter. Great. Thank you all very, very much. 
Appreciate your testimony.
    Dr. Murawski. Thank you.
    Dr. Armstrong. Thank you.
    Senator Vitter. I was going to, but, Senator, if you have 
any further questions----
    Senator Lautenberg. Well, just--at what point is there a 
predictability, that's reasonable from evidence that you've 
seen in your studies, that says that there is no going back to 
the conditions that we've seen before--talking about the 
shellfish, talking about what's happening with wetlands as the 
flooding takes place and so forth, what happens to those bird 
populations or the fish populations that dwell in those areas. 
Is it expected that there's always going to be some replacement 
for those? I mean, are we--if we're going to be a hot world, is 
it likely that we're going to be able to sustain life as we 
know it? I mean, one thing we know is that there's going to be 
more carbon poured into our atmosphere than there is now. 
That's--one doesn't have to be a forecaster for that. Well, 
what's that going to do to us?
    And I admire your patience, I must tell you, as you search 
the scientific routes for knowledge. But I'm an ordinary plain 
human being, and I worry about the things that I see in front 
of me, about things that change, temperatures changing, the--I 
mentioned the polar bears. There are other species that are 
under assault as a result of this. We see penguin populations. 
I've told you spent time in Antarctica, and went to the South 
Pole, and scientists who are working there are very worried 
about what's happening.
    And, at some point, when do we extinguish the fire before 
it totally consumes the forest? And at what point do we work on 
these problems that we see in front of us to say there's enough 
out there to alarm us, to--for us to say, ``Hey, we're going to 
find out more about the natural cycles that can be 
anticipated?'' But we know something that we're doing that has 
affected it. There's a report by the National Academy of 
Sciences that say that the human influence on us is a--the 
changes observed--temperature is, in fact, rising. It's--the 
changes observed over the last several decades are likely 
mostly due to human activities. We can't rule out that some 
significant part of these changes are also a reflection of the 
natural variability--National Academy of Science, 2001. Do we 
dismiss that in the interest of research and say, ``OK, that's 
there, but we've got to get on with it, with doing more 
research before we dampen the fire? ''
    Dr. Murawski. Sir, I think most of the research that we're 
trying to do is to try to frame these sets of issues for 
people, as yourself, the people who make public policy, in 
terms of how we're going to make adjustments or mitigation or 
adaptation to these issues. And we're trying to narrow the 
bounds of uncertainty, and to try to understand particularly 
the regional effects, which will play out in many of the 
examples that you talked about.
    As to what we do about them, it's a much larger problem 
than scientists can actually deliver the information and the 
bounds of certainty, but this is in the public-policy arena.
    Dr. Armstrong. Sir, one of our----
    Senator Lautenberg. Doctor?
    Dr. Armstrong.--responsibilities is--at USGS is--being the 
science wing of the Department of the Interior, is to provide 
science information to our land resource brethren at National 
Park Service, Bureau of Land Management, Fish and Wildlife 
Service, Bureau of Indian Affairs. And I will tell you that the 
problems that you've addressed today are real problems, and 
they are things that we are--the response of polar bears, of 
seals, of invasive species, of plants and other animals, 
especially in climate-sensitive areas, are things that we are 
currently addressing and looking into and trying to develop an 
understanding of the cause and effect. What causes a polar bear 
to lose weight, or what causes a seal population to migrate to 
other areas? We're looking at these things now.
    And I would actually say to you that it would be 
irresponsible of us, as scientists, not to provide you the 
information you need and to give you our best professional 
judgment. But, in doing that, we need to show you, also, what 
degree of certainty and what kind of confidence level can we 
give you that information you need to make decisions with. And 
that's the thing that we're working on now, is trying to better 
understand those cause-and-effect processes.
    Senator Vitter. Second panel.
    Senator Lautenberg. Yes, OK. So--and I'll wrap up here--I 
just--would it be advisable for us to try to reduce 
deforestation of our wooded lands? Do they matter? Would it be 
wise for you folks to say, ``Hey, listen, cut down on the 
amount of carbons that are released into the atmosphere''? 
We're--is that a good idea, or is that to be left for another 
day or another year, another century?
    Dr. Armstrong. I think it's appropriate for the 
policymakers and the resource managers to give you that 
information that they determine to be appropriate. At USGS, 
it's up to us to provide the science to those people that make 
those decisions.
    Senator Lautenberg. Thank you.
    Senator Vitter. Thank you all very much.
    Dr. Armstrong. Thank you.
    Senator Vitter. And as the second panel is taking the 
witness table, I'll begin to introduce our three panelists who 
comprise the second panel.
    First we'll hear from Dr. Syun-Ichi Akasofu, Director of 
the International Arctic Research Center in Fairbanks, Alaska. 
And we thank him, again, for traveling such a distance to be 
with us. We're also joined by Dr. Robert Corell, Senior Policy 
Fellow of the American Meteorological Society and affiliate of 
the Washington Advisory Group; and, also, Dr. Paul Reiter, 
Professor of the Institut Pasteur, in Paris, France. And we 
also thank him for traveling such a long distance.
    And as soon as everyone is settled, we'll begin with Dr. 
Akasofu's testimony.
    Thank you.
    The Chairman. Could I introduce Dr. Akasofu to you?
    Senator Vitter. Absolutely, Mr. Chairman.
    The Chairman. I just think you should know that Dr. Akasofu 
conceived the idea of the Arctic Research Center and obtained 
the support of Japan and of Canada and the United States, and, 
to a certain extent, of Russia, for the activities that are 
conducted there. This is an international center. Substantial 
Japanese funds have gone into that, as well as others. And I 
think we owe him a debt of gratitude for what he's done, 
dedicated a substantial portion of his life to this one area of 
    Senator Vitter. Absolutely. I agree completely.


    Dr. Akasofu. Mr. Chairman and members of the Subcommittee, 
I really appreciate, thank you for providing me with the 
opportunity to testify at this important hearing today.
    The Chairman. Syun, pull the mike toward you, will you? 
Pull it right----
    Dr. Akasofu. Let's see. As Senator Stevens says, that I am 
the Director of the International Arctic Research Center. 
Senator Stevens helped us to establish the center. We have been 
working on--specifically on climate change.
    I would like to summarize my testimony. And the most--the 
prominent warming in the world was taking place in the 
continental Arctic during the last half of the last century. 
So, it--the three times more than the rest of the world. So, 
the warming signals are the largest, so we like to concentrate 
on that to try to understand it.
    The--in the continental Arctic, we have--because of 
warming, we have degradation of permafrost--forests and so on, 
and many other phenomena.
    However, we have at least two firm scientific indicators 
that show it is incorrect to conclude that this warming in the 
continental Arctic is due entirely to the greenhouse effect 
caused by man. The first indicator is that most advanced 14 
IPCC global climate models, which includes the best scientific 
knowledge of the greenhouse effect, cannot reproduce the 
warming of the continental Arctic during last half of the last 
century. The IPCC cannot reproduce. This is what we call 
hindcasting. We are using last 50 years of data, last IPCC--
best IPCC group to reproduce that. And so, we think it's best 
scientific test of the greenhouse hypothesis.
    In the scientific methodology, what we do is we make 
observation--in this case, global warming. Then we hypothesize 
the causes of the warming, the second step. And the last step 
is to verify the hypothesis. If necessary, using the 
supercomputer. And if computer simulation and observation 
agree, then the observations and the--our understanding becomes 
scientific fact.
    But if there is--computer cannot reproduce what we observe, 
then the hypothesis has to be disproved. And--but you still 
insist that--someone still insists that greenhouse effects is 
going, then that belongs to the area of what we call science 
fiction, because the science fiction you don't have to rely on 
any science.
    So, then--so, the first test is, we cannot reproduce the 
continental warming, which is--as the largest, most prominent 
feature of the warming today. The second indicator is that 
geographic pattern of the warming in the Arctic has been 
drastically changing during the last--in recent years. Strong 
continental Arctic warming trend is no longer evident during 
the last two decades.
    If the warming trend during the last half of the last 
century were entirely due to the greenhouse effect, the past 
geographic pattern of the warming should intensify, but this is 
not the case. Various warming and cooling of similar magnitudes 
has continuously occurred at different locations and different 
times during the last hundred years. So, it's natural to 
conclude that such a trend will continue, as Dr. Armstrong 
said, the--both natural and manmade component.
    In addition, long-term record of the glaciers and the sea 
ice show that they have been--those glaciers and the sea ice 
have been receding around about 1,800, well before the CO2 
effects became serious. We have some evidence that the present 
recession of sea ice in the Arctic Ocean is due partly to the 
intrusion of warm North Atlantic water, which is caused by what 
we call North Atlantic oscillation, a natural phenomenon, like 
El Nino. So, this warm water is now flowing around the Siberian 
coast and approaching Alaska.
    Also, it's very important to notice that our sun is 
changing. The solar physicists have been working on this for 
years, and they've found that very important solar output is 
    So, it is my conclusion that it is urgent to identify both 
natural and manmade components of the present warming. So, 
results that will be--of--like house-fire example that Senator 
mentioned, we are not sure if the house is really on fire. And 
to put the water where it would make water damage may be more 
    That's my testimony.
    [The prepared statement of Dr. Akasofu follows:]

 Prepared Statement of Dr. Syun-Ichi Akasofu, Director, International 
         Arctic Research Center, University of Alaska Fairbanks
    Thank you for providing me with the opportunity to testify at this 
important hearing today.
    In order to avoid any misunderstanding, I would like to state at 
the outset that it is in the best interests of mankind to reduce the 
rate of increase of our release of CO2. My talk is about how 
much this future reduction should be. For this purpose, I would like to 
demonstrate that:

        1. Prominent climate change is in progress in the Arctic, 
        compared with the rest of the world. However,

        2. arctic climate change consists of both natural change and 
        the greenhouse effect, and thus

        3. it is incorrect to conclude that the present warming in the 
        Arctic is due entirely to the greenhouse effect caused by man.

        4. Therefore, it is important to find out the contribution of 
        both natural and manmade components to the present climate 
        change in the Arctic.

    The first statement can be illustrated in Figure 1. The range of 
temperature change along the coastline of the Arctic Ocean is much 
greater than that of the global average. Please note a rapid increase 
from 1920 to 1940, a decrease from 1940 to 1970, and a rapid increase 
again from 1970 on.

    It is also important to note that both the Arctic and global 
temperatures began to decrease in about 1940, when our release of 
greenhouse gases began to increase rapidly. Thus, the increase-decrease 
between 1920 and 1970 must be natural change. One important task we 
have is to find out the nature of the warming periods from 1920 to 
1940, and from 1970 to the present time. An important question is 
whether or not the present rise will continue or whether future 
temperatures will decrease, as was the case during 1940 to 1970.
    Let us examine where in the Arctic temperature changes occurred 
during the last half of the last century. The left-hand side of Figure 
2 shows clearly that the most prominent warming was in the continental 
Arctic (Siberia, Alaska, and Canada), except in Greenland, where it 

    The IPCC Arctic Group, consisting of 14 Global Climate Modeling 
(GCM) teams headed by V. Kattsov, tried to reproduce the temperature 
change for about the same time period on their models. Their results 
are shown in the right-hand side of Figure 2. The simulation result 
bears no resemblance to the observed, real temperatures in the 
continental Arctic. If the simulation were reasonably accurate, the 
results should be similar. This is the most quantitative test to date 
to examine if the continental arctic warming during the last half of 
the last century was caused by the manmade greenhouse effect. This 
comparison shows clearly that much of the prominent warming in the 
continental Arctic after 1970 was not caused by the human-induced 
greenhouse effect.
    If, in fact, the continental warming indicated in the right-hand 
side of Figure 2 were caused by the greenhouse effect, this trend 
should have been intensified during the last few decades. However, that 
is not the case. The continental warming in the upper part of Figure 3 
(which is similar to the left-hand side of Figure 2) is absent during 
the last 20 years (the lower part of Figure 3). Thus, the continuous 
increase of the warming is not taking place any more. Instead, intense 
warming is now in progress in Greenland, which experienced cooling in 
the recent past.

    Further, let us examine temperature changes during the last 
century. Figure 4 is similar to Figure 1, except it includes the 
Subarctic, and the zero line represents the average value of the last 
century. One can see that warming and cooling continuously occurred 
during the last century. Thus, it is not difficult to infer that the 
rise after 1970 is not entirely due to the manmade greenhouse effect.

    Fortunately, we now have longer-period ice core data from an island 
in the Arctic Ocean. It is shown at the top of Figure 5. The bottom 
trace is the reproduction of Figure 1, and the middle one is the 
temperature record in northern Norway. All three traces show similar 
change from 1900. In addition, the ice core data show clearly that 
there are both linear and irregular changes from 1725, well before the 
effects of the Industrial Revolution became serious. Thus, it is clear 
that the last rise since 1970 is not entirely due to the greenhouse 

    It is likely that part of the rises and falls of temperature in 
1920-1970 can be identified as what is called a ``multi-decadal 
change.'' One possible cause of this multi-decadal change is the 
changing intensity of the intruding warm North Atlantic water into the 
Arctic Ocean (Figure 6), which is associated with a natural phenomenon 
called the North Atlantic Oscillation (NAO). At the present, the warm 
water is flowing toward the Alaska coast. Studying and tracking this 
warm-water pulse, which may be a natural reason for some loss of sea 
ice, is one of the major projects of the International Arctic Research 
Center (IARC), conducted with the help of the Russian Icebreaker 
Kapitan Dranitsyn.

    In recent years, there have been a large number of reports that 
both glaciers and sea ice in the Arctic Ocean have been receding. 
However, longer-term records show that such phenomena have been in 
progress continuously since 1800 or earlier (Figures 7a and 7b), and 
are not phenomena that began after 1970. Glaciers in the Glacier Bay 
National Park began to recede at least by the time Captain Vancouver 
passed by in 1794, and the ice edge in the Norwegian Sea began to 
recede in about 1800.

    These data show clearly that it is dangerous to infer causes of 
climate change using only data that cover the last 40 years or so. In 
recent years, there have been a large number of excellent papers that 
describe arctic climate change since about 1970. This is because high 
quality satellite data became available only after 1970. Fortuitously, 
this period also coincides with the beginning of temperature rise 
during the last several decades. Thus, all such reports on scientific 
results are naturally related to the topic of rising temperatures.
    Although I respect the authors of those papers, I cringe somewhat 
when the papers are consumed immediately by the media and then the 
public. Unfortunately, members of the press often champion these papers 
as showing examples of the greenhouse effect, which tends to 
sensationalize the results. Thus, the general public often interprets 
the results to mean that all climate change in the Arctic must be 
caused by the manmade greenhouse effect.
    These scientific reports should be treated like any other 
scientific papers in professional journals. Any significant conclusions 
should be scrutinized by the scientific community before they become 
material for public consumption. This requires a certain period of 
time. Although I am happy to have the present great public interest in 
our research topic of global warming, such instant reporting of results 
for relatively short time periods can cause much confusion in the minds 
of the public. It is not as simple as stating that ``warming melts 
    Unfortunately, data gathering for periods before the 1970s is much 
more difficult and much more time consuming than obtaining satellite 
data. Today, many climatologists tend to avoid dealing with the topic 
of climate change before the 1970s. Further, those data may not be of 
the quality researchers desire, and some researchers tend to discredit 
results based on data before 1970, which is a good excuse to avoid 
longer-period data. Therefore, these days there are only a handful of 
researchers who deal with climate changes over the last century in 
great detail. In fact, it is alarming that only a few researchers in 
the world are studying the sharp increase of temperature that occurred 
from about 1920 to 1940 and the sharp decrease that occurred from 1940 
to 1970.
    Our understanding of the change between 1920 and 1970 is crucial 
for interpreting the rapid rise from 1970 on and also for future 
predictions, because the change between 1920 and 1940 is most likely a 
natural one. If computer modeling were adjusted to reproduce the 
present rise, assuming that the present rise is due entirely to the 
greenhouse effect, its prediction for future years will not be 
    We tend to forget that some climatologists, who were studying the 
temperature decrease from 1940 to 1970, warned the public that a new 
Ice Age was just around the corner. Apparently, we have not learned the 
lesson of the ``new Ice Age mistake'': short-period data do not tell 
the whole story.
    In conclusion, the nature of the climate change after 1970 should 
be a matter of great debate. It should not be assumed that this short 
period of warming is entirely due to the greenhouse effect caused by 
the actions of man. The prediction of future trends depends greatly on 
the understanding of the nature of the rise after 1970.
    Thank you again for the opportunity to present this testimony 
today, and thank you for your interest in this important issue. Please 
feel free to contact me if you have any additional questions.
ACIA (Arctic Climate Impact Assessment), Cambridge University Press, 
Fritzsche, D., R. Schutte, H. Meyer, H. Miller, and F. Wilhelms, T. 
            Opel, L.M. Savatyugin, Late Holocene ice core record from 
            Akademii Nauk Ice cap, Severnaya Zemlya, Russian Arctic, in 
            Papers accepted for publication in Annals 42, International 
            Symposium on Arctic Glaciology, Geilo, Norway, 23027 August 
            2006, J.W. Dowdeswell and I.C. Willis, Eds., Annals of 
            Glaciology, No. 42, A150, 2006.
Hansen, J., L. Nazarenko, Reto Ruedy, Makiko Sato, Josh Willis, Anthony 
            Del Genio, Dorothy Koch, Andrew Lacis, Ken Lo, Surabi 
            Menon, Tica Novakov, Judith Perlwitz, Gary Russell, Gavin 
            A. Schmidt, and Nicholas Tausnev, Earth's energy imbalance: 
            Confirmation and implications, Science, Vol. 308, no. 5727, 
            pp. 1431-1435, doi:10.1126/science.1110252, 2005.
IPCC (Intergovernmental Panel on Climate Change), http://www.ipcc.ch.
Polyakov, I., R.V. Bekryaev, G.V. Alekseev, U. Bhatt, R. Colony, M.A. 
            Johnson, and A.P. Makshtas, Variability and trends of air 
            temperature and pressure in the maritime Arctic, 1875-2000, 
            J. Climate, 16(12), 2067-2077, 2003.
Polyakov, I.V., G.V. Alekseev, L.A. Timokhov, U. Bhatt, R.L. Colony, 
            H.L. Simmons, D. Walsh, J.E. Walsh, and V.F. Zakharov, 
            Variability of the intermediate Atlantic Water of the 
            Arctic Ocean, over the last 100 years, J. Climate, 17(23), 
            4485-4497, 2004.
Vinje, T. Anomalies and Trends of Sea-Ice Extent and Atmospheric 
            Circulation in the Nordic Seas during the Period 1864-1998, 
            J. Climate, 14, 255-267, 2001.
Wiley, S.D., Blue Ice in Motion: the story of Alaska's Glaciers, The 
            Alaska Natural History Association, 1990.

    Senator Vitter. Thank you very much, Doctor.
    Dr. Corell, welcome.





    Dr. Corell. Thank you, and good afternoon, Mr. Chairman, 
Senator Stevens, Senator Lautenberg, and all gathered here. I 
really appreciate the opportunity to join you in this hearing 
    I'd like to put some context for our discussion, because 
there have been significant shifts of the climate in our 
planet, with substantial changes and increases in temperature, 
particularly during the last 150 years or so, as reported by 
Professor Moberg and many others who have documented, as 
depicted here, the picture over the last 2,000 years, the so-
called hockey stick. And, as you can see, the instrumental 
record is clear that things are happening in the last 150 years 
that certainly are unparalleled in the last 2,000 years.
    The IPCC third report concludes that while some of the 
fluctuations we see--and you can see them here, they are 
natural in character--come from natural variability, it is 
clear now, to the IPCC any ways, that human influences are 
responsible for most of the roughly 1 degree Fahrenheit global 
warming that has occurred over the 20th century, and that the 
IPCC predicts and suggests that those temperatures, over the 
next hundred years, may reach as much as 5 to 9 degrees 
    First let me say a word or two about the ocean and the 
marine setting. A simple and important message, the oceans 
control the timing and magnitude of the changes of the climate 
system, and do so over decadal timescales. Further, the--any 
imbalance of incoming radiation--and we do have an imbalance at 
the moment--90 percent of that energy ends up in the ocean. The 
10 percent is what we hear about, reducing sea ice, melting 
glaciers, warming the atmosphere. So, the oceans are the 
dominant player in the situation.
    Professor and Dr. Hansen and his group in Columbia have 
done an extensive study of the last 10 years of this increased 
warming of the ocean, and have concluded that the Earth is now 
absorbing about .85, plus or minus a small amount, watts per 
square meter. That number doesn't mean anything, but it does 
mean the following, and that is, already stored in the ocean is 
another .6 degrees, or roughly 1 degree Fahrenheit, of warming 
of the planet without any further increase of greenhouse gases 
in the atmosphere. So, it's like a supertanker. It stores it, 
and it takes a long time for it to play out.
    And, in that regard, Mr. Chairman, in answer to your 
question, at least when we're combining warming that's due to 
both natural and anthropogenic factors, it's clear that there 
is a lead-lag relationship, that, as CO2 goes up and 
the warming takes place of the ocean, it will take a somewhat 
longer time for that to be expressed as a warming of the 
overall atmosphere.
    This oceanic warming has a wide range of impacts, both 
physically and biologically. The first is that there's a long-
term effect on sea level, which I'll come back to. As the heat 
is propagated downward into the ocean, we're only heating the 
upper few hundred meters already, and we have 4,000 meters to 
go. And as that heat propagates down, the oceans expand, and 
sea level will continue to rise. And I should note that most of 
the sea-level rise that we've experienced to date has come from 
this thermal expansion of the ocean, and not from land-based 
ice melting.
    As Dr. Murawski has indicated, there certainly is a clear 
impact on fisheries, marine mammals, sea birds, and other 
marine life, and it will have a significant change in the 
future. The shift in fisheries have already been observed, and 
will continue to occur as both oceanic temperatures and 
currents shift. Marine mammals, including walrus, sea whale, 
seals, and polar bears, are already being impacted, as Senator 
Lautenberg aptly pointed out.
    While the ocean, as a whole, can store vast amounts of 
CO2, it's not very well mixed, and much of that 
absorption of CO2 builds up near the surface. And 
this has the effect of altering the oceanic chemistry and 
resulting in increased acidity of the ocean, which has already 
been noted by previous testimony.
    What I'd like to note here is that as the CO2 in 
the atmosphere increases from our present level, about 380 or 
so parts per million, up toward the 6-700 region, laboratory 
experiments on the calcification process of plankton strongly 
indicate that these animals--or these plants at the lower end 
of the food chain will have a very difficult time forming. And 
you can see the difference between the lower left and the lower 
right. So, the acidification will play a profound role, and the 
impact in the whole life chain in the oceanic region.
    The extent of summer sea ice has already been reduced by 
about 20 percent in the past 20 years or so, and the Northern 
Sea route is already opening up along the Russian coast, which 
will, in the end, open up seaways that are about 45 percent 
closer in time between the two markets of the Far East and 
    What are some of the impacts in the terrestrial biosphere? 
Changes in CO2 itself will have an effect on the 
terrestrial biosphere. As a result, higher concentrations will 
lead to greater carbon uptake by plants. Storage in the plant 
material will increase as long as the soils have adequate 
nutrients, such as nitrogen, to support it. Food production 
will likely increase in the short term, or at least until 
concentration gets sufficiently high that--where other factors 
will start limiting their productivity.
    So, for natural systems in forests and grasslands, the 
situation is likely to be even more problematic than it is in 
the agricultural region. Each ecosystem has a preferred set of 
conditions, relationships between each element in the system. 
And as the climate shifts some range--some ecosystem elements 
can move slowly, some move fastly. And, therefore, the out-year 
composition of those ecosystems is likely to be quite different 
than they are now.
    The temperature increases that we've already experienced in 
Alaska since 1970 in the Kenai peninsula have indicated how 
disastrous those modest temperature increases can have, because 
the over-wintering of the spark--the spruce bark beetle has 
already led to sudden and really widespread loss of the white 
spruce forests.
    Finally, the projected increase in frequency of droughts, 
wildfires, floods, and other extremes, such as hurricanes, are 
the kind of thing that we can expect to have impact not only on 
our ecosystems, but on our society as a whole. And because 
these projected changes are evident in the frequency of the 
events, the timing and the intensity, and the localization of 
some of the participation, all sorts of challenges lie ahead, 
some of which we have ability to see, others of which will 
require continued research, and one of the most important of 
which is the status of freshwater reserves around the planet.
    Now, in the Arctic, the melting of snow cover and the 
river-ice permafrost combined with the loss of sea ice has had, 
and will continue to have, a really profound effect on 
wildlife, particularly on its movement across the regions. 
Warmer species--warming conditions have already resulted in new 
species. If you go to the Inuits, in the north of Canada, the 
word ``robin'' doesn't exist in their vocabulary or in their 
language, and robins are now prolific in those regions.
    As a result of these kinds of changes across the U.S. and 
also around the world, conditions such as heat waves, drought 
conditions, will be more favorable to propagate wildfires, as 
Alaska has experienced one of the most incredible wildfires a 
couple of years ago, of 600--6.5 million acres destroyed in one 
    On the other side of the precipitation question, there is 
going to be more intense----
    Senator Vitter. Doctor, if you could start to sum up, I 
want to----
    Dr. Corell. I would--surely. There will be more intense 
rainfall, which will result in more flooding.
    I want to say a word or two about Greenland. The ice 
melting there is pretty dramatic, as you can see in these 
images. And there has been a melt of about 20 percent increase 
just in the past 25 years, and last year the melt region was 
the largest in recorded history.
    Sea-level rise will have an impact, such as 1 meter of sea-
level rise on Florida, as indicated in this diagram here; and 
elsewhere around the planet, even more profound implications.
    I was just recently in Alaska to visit Shishmaref, which is 
a very important village to the Alaskans, and the picture in 
the lower right--lower left-hand corner was taken only a couple 
of weeks ago. It resulted from a storm last fall, that the sea 
ice used to protect that shoreline, and the sea ice is no 
longer there to do so. And, as a consequence, the village is 
going to have to move, at very costly levels.
    So, the Arctic now is really experiencing some of the most 
rapid and severe changes, and it's going to be that way in the 
    Let me just summarize by saying that the Arctic is one of 
the most important regions to note what's happening. As Senator 
Stevens said, it's the bellwether, it's the place in which we 
will see the most change most rapidly, and it is a part of our 
    And while it's clear to me that global change is here, 
we've got a major task ahead of us. I urge all of us to join 
together in giving this serious attention to look at 
assessments as a vehicle by which science can communicate its 
knowledge at global, regional, and national levels to 
policymakers like yourself.
    Thank you for your attention and your time.
    [The prepared statement of Dr. Corell follows:]

Prepared Statement of Dr. Robert W. Corell,\1\ Senior Fellow, American 
 Meteorological Society; Affiliate, Washington Advisory Group; Chair, 
                    Arctic Climate Impact Assessment
    Mr. Chairman, Members of the Subcommittee, and all gathered here 
today, I thank you for the opportunity to participate in today's 
hearing on the ``Projected and Past Effects of Climate Change: A Focus 
on Marine and Terrestrial Systems.'' I am honored to join you to 
explain the science that underpins understanding of the past and 
projected effects of climate change, especially in terms of the impacts 
on marine and terrestrial systems in North America, across the Arctic 
region, and around the world.
    In offering these perspectives, I will be drawing primarily from 
the findings of major scientific assessments, a number of which I have 
been involved with, because these assessments very thoughtfully draw 
together the collective findings of the scientific community. These 
assessments deserve very high and special consideration because their 
credibility has been well established as a result of their extensive 
open review processes, which have helped to carefully hone their 
    At the national level, I will be drawing upon the results of the 
U.S. National Assessment that was completed 5 years ago.\2\ In my role 
from 1990-1999 as chair of the Subcommittee on Global Change Research 
that directed the U.S. Global Change Research Program, I was 
instrumental in the organization of this assessment, and after I left 
government service I served on the National Assessment Synthesis Team 
that summarized the assessment's findings. In describing potential 
consequences for the Arctic, I will be drawing mainly from the results 
of the Arctic Climate Impact Assessment (ACIA), which was completed in 
2004,\3\ having been established and charged to conduct the assessment 
by the Arctic Council \4\ and the International Arctic Sciences 
Committee.\5\ For ACIA, I served as chair, leading an international 
team of over 300 scientists, other experts, and elders and other 
insightful indigenous residents of the Arctic region in preparing a 
comprehensive analysis of the impacts and consequences of climate 
variability and changes across the Arctic region. At the international 
level, I will be drawing mainly from the results of the 
Intergovernmental Panel on Climate Change (IPCC), which I was 
instrumental in helping to conceive in the late 1980s in my role as 
Assistant Director for Geosciences at the National Science Foundation 
(NSF) from 1987-1999. The IPCC's members are the nations of the world 
and the periodic assessments that they commission represent the 
collective evaluation of scientific understanding by the international 
scientific community. That the IPCC's assessments of 1990, 1995, and 
2001 have been unanimously accepted by the world's community of nations 
gives a strong indication of the widespread agreement that exists 
regarding the major finding that human-induced climate change is 
already influencing the climate and the environment and that much 
larger changes lie ahead.\6\ For more detailed information and 
scientific citations on most of my points, reference should be made to 
the cited assessments. In areas where the pace of research has been 
especially rapid or significant in recent years, however, I will also 
be drawing upon the results of more recent scientific articles, which I 
will specifically reference.
Context for Today's Hearing
    The IPCC's Third Assessment Report \7\ summarized the peer-reviewed 
scientific evidence that human activities, in particular the ongoing 
emissions of carbon dioxide (CO2) and other greenhouse gases 
to the atmosphere resulting primarily from the combustion of coal, oil, 
and natural gas, are causing the Earth's climate to warm more rapidly 
and persistently than at any time since the beginning of civilization. 
While some of the fluctuations are likely a result of natural factors 
(e.g., variations in solar irradiance and major volcanic eruptions), 
the IPCC evaluation concluded that the strength and patterns of these 
change makes clear that human influences are responsible for most of 
the roughly 0.6+C (1+F) warming during the 20th century. In particular, 
despite the cooling influence of the 20th century's largest volcanic 
eruption in 1991, the fifteen warmest years in the instrumental 
temperature record available since 1860 have all occurred in the last 
25 years,\8\ and comparison with paleoclimatic reconstructions \9\ of 
temperatures over the last two thousand years indicates that recent 
warmth is unprecedented, at least for the Northern Hemisphere where 
paleoclimatic data are most available.\10\ In addition to the warming 
of the surface, which has been particularly strong in the Arctic,\11\ 
warming is also evident in ocean temperatures (causing some of the sea 
level rise), below ground temperatures, and temperatures well up in the 
troposphere.\12\ Other evidence of climate change includes diminishing 
sea ice and snow cover in the Northern Hemisphere, melting back of 
mountain glaciers in the tropics and in most other locations around the 
world, and an increasing tendency for precipitation to occur in 
relatively heavy amounts.
    For the future, IPCC projects that significantly greater warming 
lies ahead. Considering a wide range of possible scenarios for how 
human activities (e.g., changes in population, technological 
development, energy use and supply, economic development, and 
international cooperation) are likely to alter atmospheric composition 
during the 21st century, the IPCC projects a further increase in 
average annual surface air temperature around the globe of roughly 1-
2+C (1.8-3.6+F) from 1990 to 2050 and a further 1-2.5+C (1.8-4.5+F) by 
2100, bringing the projection for total human influence from the start 
of the Industrial Revolution to 2100 to roughly 2.5-5+C (about 4.5-
9+F).\13\ As is the case for the warming over the 20th century, future 
changes are expected to be greater over land than over the ocean, 
greater in mid- to high latitudes than in low latitudes, and, except 
where regions really dry out, greater during the winter than during the 
summer and greater during nighttime than daytime. As will be explained 
more fully in discussing likely impacts, many other aspects of the 
world's weather and climate will also be affected.
    That such changes in the climate will occur as a result of human 
activities is no longer scientifically controversial. During the rest 
of my testimony, I will discuss what the likely consequences of the 
changes in atmospheric composition and climate are likely to be for the 
environment, focusing on three specific domains:

   Oceans and marine systems;
   The terrestrial biosphere; and
   The interface between the marine and terrestrial 

    My discussion will focus on the links between climate change and 
these systems. It is important to recognize, however, that a number of 
additional stresses are affecting each of these environments, including 
air pollution, nitrogen deposition, toxics such as mercury, 
unsustainable extraction of resources, over-fishing, nutrient-induced 
eutrophication, depletion of stratospheric ozone and UV enhancement, 
etc. Climate change is thus only one aspect of global environmental 
change, although a continuously accumulating one that over time will 
have very large impacts, and for a full evaluation of likely 
environmental consequences for both marine and terrestrial 
environments, comprehensive research and assessment efforts are 
Interactions and Impacts Linking Climate Change and the Ocean and 
        Marine Environment
    Oceans cover about 70 percent of the Earth's surface. Because of 
their large heat capacity, the oceans moderate climatic swings by 
supplying heat to the atmosphere and adjacent continents during the 
winter and, because they warm relatively slowly during the summer, are 
the source of cooling sea breezes during times of peak solar radiation. 
Much of the heat absorbed by the oceans goes into evaporating water, 
providing the moisture that supplies vital precipitation for land areas 
via the monsoons and tropical and extratropical storms. These rains and 
associated geochemical interactions help to cleanse the atmosphere of 
pollution. In addition, oceans support a wide diversity of biological 
life that supplies fish, birds, marine mammals and other species higher 
in the food chain, and supports the fisheries that in turn provide 
substantial food for humans.
    While the oceans seem so large that it is hard to imagine that 
human activities could affect them, records over geological time and 
observations of recent changes make clear that both the physical and 
biological systems in the ocean are quite sensitive to changes, and, 
indeed, are being affected. The very human activities that are causing 
the climate to change are becoming the major influence on the oceans.
    First, the oceans affect atmospheric chemistry. In their natural 
state, cold waters forced to the surface by wind patterns in low 
latitudes release large amounts of CO2 to the atmosphere as 
they warm. Before humans started altering the carbon cycle, roughly the 
same amount was taken up in mid- to high latitude ocean areas as the 
ocean waters cooled and marine organisms grew, died and sank to the 
ocean depths. With this balance, which was modified somewhat during 
glacial periods when the oceans were colder, the atmospheric CO2 
concentration has been held in the range of about 180 to 300 ppmv \14\ 
for the past several million years. As human activities began to emit 
large amounts of CO2 as a result of combustion of coal, oil, 
and natural gas, the atmospheric concentration has been driven higher 
because the oceans and living biosphere cannot absorb it all. On time 
scales of years to centuries, the oceans take up about a third of the 
emitted amount, limiting the atmospheric buildup and thus moderating 
the pace of climate change.
    While the oceans as a whole can hold vast amounts of dissolved 
CO2, the oceans are not well mixed vertically, and so most 
of the added CO2 builds up in the near surface layer. This 
has the effect of altering oceanic chemistry, most importantly by 
making the ocean more acidic.\15\ Increasing oceanic acidity has a 
range of effects, but the most important is that it makes it chemically 
more difficult for marine organisms to form shells. For corals, the 
rise in the CO2 concentration from its preindustrial value 
of about 280 ppmv to its present value of 380 ppmv has already caused a 
significant shrinkage in the regions most favorable for reef-forming, 
and by 2050, virtually all of the most favorable regions in the world 
will have disappeared, simply due to the rise in the CO2 
    Adding in the sensitivity of corals to warmer ocean waters (the 
``coral bleaching'' effect), the prospect for more powerful storms and 
wave conditions, the increasing threats from coastal runoff and fish-
harvesting, and other stresses, the prospects for many of the world's 
reefs are very problematic. While the potential impacts on coral are of 
most immediate concern, impacts on other shell-forming organisms are 
also likely to become significant over coming decades, particularly as 
the CO2 level approaches 750 ppmv.\17\
    As the rising concentrations of CO2 and other greenhouse 
gases have trapped more infrared radiation, making it more difficult 
for the Earth's surface to cool, most of the additional heat has been 
taken up by the oceans because they are capable of mixing it through 
the upper hundred meters (yards) or so of ocean depth. Surveys of ocean 
temperature give a clear indication that the ocean's upper layers are 
warming; \18\ indeed, the warming that is being observed is in good 
agreement with climate model simulations of how the oceans are being 
projected to warm as a results of the changes in atmospheric 
    This oceanic heating is having a wide range of both physical and 
biologically important impacts. Because the oceans are able to mix the 
heat downward, they are able to slow the warming of the atmosphere, 
which is beneficial, but it also means that we are not experiencing the 
full extent of warming to which past emissions of CO2 have 
committed the world. Experiments with climate models indicate, for 
example, that the world would be committed to further warming of about 
0.5+C (almost 1+F) even if global emissions of CO2 were to 
be quickly cut to near zero.
    Warming of the oceans also makes more energy available to the 
atmosphere if just the right conditions prevail. For example, warm 
ocean waters provide the energy needed to intensify tropical cyclones 
(i.e., hurricanes and typhoons), and indeed, recent studies \20\ are 
finding that increasing sea surface temperatures are leading to an 
increasing proportion of tropical cyclones to be in the most powerful 
and destructive categories (more on the consequences of more powerful 
tropical cyclones in the section dealing with the ocean-land 
interface). While there has been significant debate recently about 
whether the available record provides a definitive indication of this 
linkage, a paper in press in the Bulletin of the American 
Meteorological Society, of which I am a co-author, finds that there are 
many reasons to suggest that there is indeed a strong linkage and that 
it may well be limitations in our detective work that are the 
problem.\21\ If this is indeed the case, and it seems quite likely, 
then the world faces a situation where the storm season is becoming 
longer, storms may well last longer, and the likelihood of relatively 
intense storms is increasing, likely leading to greater and greater 
destruction and loss of life unless our adaptive efforts \22\ are 
significantly increased.
    Climate change also has the potential to influence the pattern and 
character of the normal year-to-year fluctuations of the climate. For 
the Pacific region and then for much of the U.S., the natural variation 
of the El Nino-Southern Oscillation (ENSO) is of critical importance, 
variously causing El Nino and La Nina events (i.e., unusual warming or 
cooling in the eastern tropical Pacific, respectively) that redirect 
the Northern Hemisphere jet stream, thereby creating either quite wet 
or quite dry winter conditions across various parts of the U.S. (e.g., 
this year, the ocean conditions are causing the U.S. West Coast to be 
inundated with very large amounts of rain). Research to date only hints 
at how ENSO may be affected, with some indication that the overall 
conditions may become more El Nino-like with more intense El Nino 
events (meaning, for example, more winter precipitation for California, 
increasing flooding potential in the spring and increasing the stock of 
burnable vegetation). However, there remains significant disagreement 
among model results and this area is, therefore, being investigated 
intensively by various research groups.
    Changes in atmospheric winds and weather (a result of the warming) 
and increasing ocean temperatures (which also feed back to affect the 
weather) also lead to changes in ocean currents. Under normal 
conditions, warm ocean waters are pulled poleward to replace cold 
waters that sink to the ocean depths in high latitudes. As these waters 
are pulled poleward, for example in the Gulf Stream, heat is given off 
that tends to keep Europe relatively warm in winter, given its 
latitude. As climate change prevents ocean waters in high latitudes 
from cooling as much, the rate of sinking waters declines, and so less 
warm water is pulled poleward, providing less winter heat. While this 
slows the human-induced warming rate in Europe, it leaves that heat in 
lower latitudes, causing those regions to be warmer and even more 
moisture to evaporate, moisture that is likely to result in more 
intense rainfall events. Slowing the generation of oceanic deep water 
also slows the transport of dissolved CO2 into the deep 
ocean, releasing somewhat the oceanic brake on the pace of global 
    Fisheries, marine mammals, seabirds, and other marine life will all 
be significantly affected by these changes. Both the increasing 
temperature and freshening of upper ocean waters in some regions by 
increased precipitation will tend to increase stratification of the 
upper ocean, affecting the vertical distribution and productivity of 
biological activity.\23\ Shifts in fisheries will occur (and some 
changes are already being observed) as ocean temperatures shift and 
changes in abundance will occur as the amounts of upwelling nutrients 
and associated biological activity are reduced. The retreat of sea ice 
will also lead to changes in fisheries, as the ice edge is normally a 
very productive site as a result of the release of nutrients from the 
melting ice and the protection from intense waves provided by the ice 
itself. Marine mammals, including walrus, seals, and polar bears, 
depend on the presence of sea ice to raise their young and to hunt for 
food, and the retreat of ice is already having a significant 
impact.\24\ The shifts in ocean conditions, both of sea ice and of 
biological activity, are also starting to have effects on sea birds, 
which are also facing increasing competitive pressures from birds that 
normally are shifting northward as warming increases.
    An added result of sea ice retreat will be the potential for 
greater access by ships. The melting back of sea ice is already near to 
opening the Northern Sea Route that would connect the Atlantic and 
Pacific Oceans via open water north of Eurasia. Not only would such a 
route cut shipping time significantly, but the route will also increase 
seasonal access to arctic resources, both below coastal waters and on 
land (although, perversely, the summer melting of the permafrost will 
make transport over land much more difficult). Already the Northwest 
Passage is becoming navigable for icebreakers and in the decades ahead 
greater access should be possible. Environmentally, such access will 
greatly increase the risk of contamination from spills and other 
pollution, and there is virtually no experience or effective approach 
for cleaning up such spills. Politically, the increased access is 
already raising questions of sovereignty, ownership of coastal zone 
resources, and rights to the shifting fisheries that will result. The 
identification of such issues as part of the Arctic Climate Impact 
Assessment formed the basis of the policy guidance document that was 
prepared by the Arctic nations as a framework for future 
    Overall, human-induced climate change is thus already having 
significant effects on the ocean, the weather systems that the ocean 
generates, and on the biological systems that are dependent on its 
resources. Adding on the impacts of sea level rise on the coastal 
environment, which is treated below, the global oceanic environment on 
which we all depend is already screaming, at least in a figurative 
sense, for actions to greatly slow the pace of change, especially as 
roughly an equal amount of change as has already occurred is almost 
certain to result as a consequence of past human activities.
Interactions and Impacts Linking Climate Change and the Terrestrial 
    Changes in both the CO2 concentration itself and in the 
climate will affect terrestrial systems. Because CO2 is 
needed by plants to grow, the increase in its concentration will, as a 
whole, enhance plant growth and allow the stomata (pore openings) on 
the undersides of leaves to open less, allowing less harmful air 
pollution in and less moisture out, thereby improving the overall 
health and water use efficiency of plants. As a general result, the 
higher CO2 concentration will thus lead to greater carbon 
uptake and enhanced storage as plant material and in soils as long as 
nutrients and sufficient soil moisture are available. Recent studies 
suggest that the CO2 fertilization effect will be limited by 
tropospheric ozone concentrations \26\ as well as the availability of 
nitrogen in ecosystems.\27\
    However, different plants respond quite differently. Under 
conditions with adequate moisture and nutrients, many types of crops 
(key exceptions are maize, millet, sorghum, and sugar cane) respond 
quite strongly to the increase in the CO2 concentration, but 
then so too do many weedy plants, necessitating additional control 
measures. Assuming that farmers can overcome problems with weeds and 
increased occurrence of pests and that moisture amounts are sufficient, 
the per acre yield of many food crops is likely to increase by tens of 
percent.\28\ It is for this reason that the IPCC and other assessments 
suggest that overall global food production will increase, at least 
until the CO2 concentration gets much higher when the effect 
can saturate or even changeover (i.e., become essentially toxic). 
Simple economic analysis would then suggest that with more agricultural 
production, food prices will drop and that there will be sufficient 
food, at least for those who can afford it, providing a net economic 
benefit to society. However, the situation in the real world is a good 
bit more complex. In the U.S., for example, overproduction currently 
leads to the need for subsidies as a result of overproduction, and so 
an increase in productivity and a decrease in commodity prices may well 
lead to calls for larger subsidies. With the climate also changing, 
there will also be a constant need to adjust seed strains to ensure 
optimal productivity,\29\ creating greater needs for support of crop 
development programs at, for example, the land grant universities.
    In addition, while productivity will go up in both good and 
marginal farming areas, the increase will be greater in absolute amount 
in the better farming areas, and so the economics of farming in 
marginal areas is likely to worsen, leading potentially to the 
abandonment of farming in such areas unless a switch can be made to 
other crops for which there is demand (e.g., a non-food crop that can 
be used to produce biofuels). For those now growing niche crops (e.g., 
crops such as apples and broccoli in cool summer regions such as 
upstate New York and New England; tomatoes in regions where nighttime 
temperatures are cool enough for fruit to set; etc.), warming is likely 
to make such regions uncompetitive for continued production of these 
crops. Because soils are typically not fertile enough to compete 
economically with regions now growing warm season crops, farming in 
such regions is also likely to be threatened. Thus, while overall food 
production in regions such as the U.S. is projected to increase, there 
are likely to be hard times for many farmers (and the rural communities 
associated with them) as adjustments occur. Lost in the transformation 
is likely to be the effective role present-day farmers play in caring 
for the land, which is likely to create ecological challenges because 
returning such regions as the southern Great Plains to their pre-
farming vegetation is unlikely to be successful due to the altered 
climatic conditions.
    For natural systems such as forests and grasslands, the situation 
is more problematic. Each ecosystem type has a set of preferred 
conditions, as is evident from the changing distributions of types of 
forest ecosystems going poleward or up a mountain. As climatic 
conditions shift, the preferred ranges for each type of ecosystem will 
shift, and numerical models that simulate this process indicate that 
the projected changes in climate over the 21st century will have 
profound effects. Starting from the Arctic (and focusing on the 
coarsest subdivision of ecosystem types), the tundra, which is summer 
home and nesting ground for many migrating birds and mammals, will be 
squeezed against the Arctic Ocean as the boreal forest becomes 
established further and further to the north. Across the United States 
and Canada, temperate forests and grasslands will push northward, with 
the northeast mixed forest giving way to more temperate vegetation and 
with forests giving way to savanna and grasslands in regions where 
precipitation does not increase enough to supply the needed moisture in 
the face of rising temperatures. For the southeastern and southwestern 
U.S., this balance will be particularly important. As described in the 
U.S. National Assessment, if the summertime conditions become warmer 
and moister, the southeastern mixed forest can persist, but if 
precipitation does not increase sufficiently, the soils will dry and 
the temperatures will increase even more, creating a situation where 
more frequent fires become likely to accelerate the transition to a 
sparser savanna woodland situation.\30\ In the southwestern United 
States, increased precipitation, particularly in the winter, may be 
sufficient to increase biological productivity in desert areas, 
allowing greater vegetation growth in winter. While seemingly 
beneficial, if summers become hotter and remain dry, the potential for 
increased fire is significant (e.g., increased wintertime growth of 
chaparral would likely only increase the likelihood of periodic fires, 
which can be particularly threatening to communities in the West).\31\
    While adapting to a situation of relatively slowly shifting 
ecosystems on the continental scale may seem comparable to adapting to 
the reforestation of the Northeast over the 20th century, the actual 
situation on the local scale, both for wildlife and for communities, is 
likely to be much more challenging. This is the case because there are 
significant variations in the response of the different plant species 
that make up the ecosystems to the changes in CO2 and 
climate, and this will mean that the preferred ranges of different 
species will shift by different amounts and at different rates, thus 
pulling apart current ecosystems without there becoming stable climatic 
conditions in which new ecosystems can evolve--instead, everything will 
be changing at once.
    Determining the thresholds that might lead to abrupt changes in the 
functioning of natural systems is, however, particularly difficult, and 
there are likely to be thresholds or tipping points that initiate a 
sequence of changes beyond which systems are likely to collapse. For 
example, a temperature increase of about 1+C per decade since 1970 in 
the Kenai Peninsula in Alaska has caused permafrost melting and allowed 
the over-wintering of spruce bark beetles and the influx of additional 
disease vectors, weakening the trees, and enhancing the extent and 
intensity of wildfire. Together, these effects have led to the sudden 
and widespread loss of the white spruce forest, and to a situation in 
which, even were the new climatic conditions stable, it would take 
centuries for new species to develop into a new, fully mature 
ecosystem; with stable conditions not likely for at least many decades, 
development of a new, mature forest system is likely far off in the 
future. As another example of the sensitivity of extant ecosystems, a 
massive die-off of pinyon pine (Pinus edulis) covering 12,000 square 
kilometers in the southwestern United States was observed during the 
recent severe drought. Although the soil moisture deficit was no worse 
than the one endured in the 1950s, the higher average temperature 
appears to have combined with the extreme dryness to make the trees 
more vulnerable to attacks from bark beetles.\32\
    Increased frequency of droughts, wildfires, floods, and other 
extremes, including greater damage from increased and more persistent 
winds and precipitation from tropical cyclones,\33\ are other types of 
changes that have the potential to exceed the adaptive capacity of 
existing ecosystems. In addition, more frequent fires and the reduced 
productivity of some ecosystems will limit the amount of carbon being 
taken up and stored by the biosphere, thus leaving a larger fraction of 
the emitted CO2 to exacerbate global warming. For example, 
the recent Indonesian fires driven by ENSO drying and human land use 
changes led to significant releases of CO2 to the 
atmosphere. A recent international comparison of coupled carbon climate 
simulations \34\ found that all of the models projected some 
destabilization of tropical ecosystems, leading to soil drying, reduced 
plant/tree growth, and increased occurrence of fire and net emission of 
CO2 to the atmosphere, thereby accelerating warming 
(positive feedback loop).\35\ Models typically suggested that by 2100 
these ``carbon-climate'' feedbacks would lead to the atmospheric 
CO2 concentration being higher by 20 to 200 ppmv \36\ and 
additional warming of 0.1 to 1.5+C, with the worst-case model scenario 
projecting the complete die off of the Amazon rain forest. These 
feedbacks are not yet well understood or represented, requiring coupled 
treatment of climate change, CO2 fertilization, nitrogen 
limitation, and the ability of trees to tap deep soil horizon water; 
however, these processes do indicate the potential for the likely 
outcome being more toward the upper end of the IPCC range of 
    Because projected shifts in the frequency, timing, intensity, and 
location of precipitation will lead to all sorts of challenges, issues 
relating to freshwater resources, although of a variety of types, were 
a common thread across all regions in the U.S. National Assessment (see 
Table 1 for a brief summary of key regional consequences). For example, 
the increased likelihood of additional wintertime precipitation in the 
western U.S., as projected in both models used in the U.S. National 
Assessment, increases the potential for mudslides and high river levels 
as well as increasing the likelihood of mountain precipitation falling 
as rain, causing accelerated loss of the snowpack, a further increase 
in runoff and an even greater likelihood of flooding. At the same time, 
warmer temperatures will lead to a rise in the snowline and, on 
average, a reduction in the springtime snowpack that is so vital for 
sustaining stream and river flows into the summer. For the rest of the 
U.S., projections indicate a continuation of the shift of precipitation 
toward more precipitation falling in the more intense (i.e., 
convective) rainfall events. Reducing the time for rainfall to seep 
into aquifers has the effect of increasing runoff, especially once the 
upper layer of soil has become saturated, thereby increasing the 
likelihood of high river levels and flooding. Warmer summertime 
temperatures, and a greater interval between significant rainfall 
events, are projected by many of the models to lead to increased 
evaporation of soil moisture in the Great Plains, and so a more rapid 
onset of drought conditions. For the Great Lakes, most models project a 
few foot lowering of lake levels as the increase in summertime 
evaporation exceeds the increase in winter precipitation, significantly 
impacting community, recreational and commercial use of lake 
waters.\38\ Reduced duration and extent of snowfall will also affect 
the Northeast and other areas, likely shortening the ski season and 
lengthening the time for warm weather recreational use of the 
landscape, assuming drying and fire do not become threats.
    In the Arctic, the melting back of snow cover, river ice, and 
permafrost, combined with offshore melting back of sea ice, will have 
significant effects on wildlife and on movement generally across the 
region. For many types of wildlife, the snow cover provides protection 
and even habitat, and climate change is likely to break vital links 
(e.g., lemmings and voles survive the winter mostly between the snow 
layer and the underlying tundra, and their loss would deplete food 
resources for snowy owls and foxes, etc.). Reindeer and caribou depend 
on the snow cover to protect vegetation that serves as winter feed, and 
episodic freeze-thaw conditions can create ice crusts that cannot be 
easily broken, reducing access to the food necessary to survive. The 
migrating herds also depend on frozen river ice in springtime to cross 
rivers along migration routes to summer breeding grounds.\39\ Warmer 
conditions are already leading to new species appearing in the Arctic, 
and these new species will tend to push existing species northward, 
likely eventually to extinction as the land ends and the Arctic Ocean 
    In addition, the melting of permafrost (and frozen sediments on the 
continental shelves) has the potential to release large amounts of 
methane (CH4) that is tied up in hydrates. On a per molecule 
basis, methane is roughly 20 times as effective as trapping infrared 
radiation as is a CO2 molecule, which is why there is so 
much attention being devoted to human-induced changes in methane 
concentrations (human contributions have caused about a 150 percent 
increase in the preindustrial CH4 concentration). While 
permafrost melting has begun, determining how much CH4 is 
being released has proven quite difficult and so the IPCC projections 
do not yet account for the potential warming influence of such 
releases, but the potential for substantial releases is quite 
significant, especially because warming in the Arctic is projected to 
be greater than for the world as a whole.
    Continued warming and changes in snowfall are also likely to 
further increase the ongoing retreat of mountain glaciers and the great 
ice sheets. In virtually all regions of the world, including on high 
tropical mountains, glaciers are retreating at a rapid rate. Because 
the annual glacier runoff in many cases serves as water resources for 
wildlife and communities, the eventual loss of the glaciers is likely 
to have very significant consequences in many regions around the world. 
The area of the Greenland Ice Sheet that melts each year is also 
increasing, and satellite observations indicate that ice mass is 
decreasing.\40\ What appears to be happening is that rather than small 
puddles forming and then refreezing in the fall, larger puddles are 
forming, and then finding channels and crevasses to flow to the bedrock 
and eventually into the ocean, allowing a greater fraction of the 
increase in downward infrared radiation caused by the higher greenhouse 
gas concentrations to go into melting of ice as opposed to the very 
energy intensive process of evaporation of water. The situation is much 
like what would happen if one of those decorative ice statues on 
banquet tables were taken out of a freezer for longer and longer 
intervals--if out for only a short period, the thin meltwater layer on 
the statue might refreeze when the statue is put back in the freezer; 
however, if kept out longer, the meltwater created each time would be 
lost, and soon there would be no ice statue at all.\41\
    Projections are that high-latitude warming of a few degrees Celsius 
(so perhaps 5+F), which is projected for the second half of the 21st 
century, would be likely to lead to the melting of roughly half of the 
Greenland Ice Sheet over a period of up to several centuries,\42\ 
mirroring a similar event that occurred during the last 
interglacial,\43\ likely mainly as the result of a particular set of 
variations in the Earth's orbit at that time that brought comparable 
warmth to high northern latitudes. The effects on sea level of such 
extensive changes are discussed in the next section.
    While much of the above discussion has focused on the projected 
changes in seasonal to annual timescale changes, what really has most 
effect on people and the environment are the extremes of the weather 
that are combined to get the changes in the averages. The weather 
(i.e., the instantaneous state of the atmosphere) is determined by the 
interaction of all of the various forcings and gradients in the global 
system. Observations indicate that day-to-day weather conditions tend 
to vary about the mean conditions in a more-or-less standard way, 
creating a bell-shaped distribution of conditions with a few instances 
much above and below the average and a greater likelihood of the 
conditions being near the average expected at each time of year. The 
projected change in climate will shift this distribution, moving the 
average higher, and thereby creating a much greater likelihood that 
conditions will exceed a particular threshold (e.g., 90 or 95+F). The 
likelihood of presently unusual events could also be changed if the 
shape of the bell-like distribution is changed, which could occur, for 
example, if the characteristics of the global circulation are changed 
(e.g., by moving the winter jet stream relative to mountain ranges such 
as the Himalayas, or by altering the oceans in ways that affect the 
irregular cycling or intensity of El Nino or La Nina events).
    As a result of the changes in climate, conditions such as heat 
waves (which exacerbate the heat index and thermal stress in cities 
\44\) and drought conditions favorable for wildfires are expected to 
become more frequent and more intense. In fact, Dai et al. (2004) 
calculate that the amount of land experiencing severe drought has more 
than doubled in the last 30 years, with almost half of the increase 
being due to rising temperatures rather than decreases in rainfall or 
snowfall.\45\ Not surprisingly, therefore, observations indicate that 
wildfires have been increasing on all continents, particularly sharply 
in North America, and projections are that this trend is likely to 
intensify with further increases in surface temperature.\46\ In 
addition, freeze events, which are important to controlling many types 
of pests and associated diseases, are projected to be less likely. As 
already mentioned, the occurrence of more intense and more frequent 
heavy rainfall events is likely to increase the occurrence of flooding. 
Analyses by Milly et al. (2002) indicate that the frequency of very 
large floods has increased substantially during the 20th century, which 
is consistent with climate model simulations, and modeling studies 
suggest that the trend will continue in the future.\47\ With respect to 
the potential severity of this type of effect, results from the 
Canadian climate modeling group cited in the U.S. National Assessment 
indicate that the return period of what are now once in a hundred year 
events will, by the end of the century, likely be reduced to about once 
every 30 years, with even more severe events occurring once every 
hundred years. In that much of society's infrastructure is only 
designed to withstand once in a hundred year events, having more severe 
events occurring more often than once a century is likely to increase 
the likelihood of very damaging events,\48\ causing very adverse and 
costly impacts for both society and the environment.
    Some media reports and criticisms by skeptics question the rising 
concern about the increasing risks from more intense and more frequent 
occurrence of extreme weather events, indicating that no specific event 
can be attributed to global warming. To better understand the 
situation, consider the simple analogy of the Earth's weather being 
equivalent to a pot of slowly boiling water, with each bubble 
indicating an extreme event somewhere across the globe. If the heat 
under the pot is turned up, there will be more bubbles, some of which 
are the size of the previous largest bubble and perhaps some even 
larger. There is no way to say that any particular bubble was due to 
the increased heat or was bigger because of it, yet clearly the 
intensified bubbling is due to the additional heat. Now, the real world 
situation is further complicated by seasonal changes (roughly 
equivalent to the heat being slowly turned up and down, but each time 
to higher levels), spatial linkages resulting from the oceanic and 
atmospheric circulations (roughly equivalent to adding noodles to the 
boiling water), and the presence of mountains and other geographic 
features (roughly equivalent to having a pot of varying shape and 
thickness); as a result formally detecting the changes in extreme 
events is indeed a challenge. But there is no question that adding heat 
to the system will lead to greater extremes (were the subtropics not so 
warm, the incidence of tropical cyclones would be much less).
Consequences at the Coastal Interface of the Terrestrial and Marine 
    At coastlines, the consequences of the changes in marine and 
terrestrial components come together. Because the coastal region 
provides habitat to so many species, from shrimp to shore birds, and 
from plant species to humans, past and projected changes occurring in 
this boundary environment have particular importance for the 
environment and society.
    Bays, inlets, estuaries, barrier islands, marshes, wetlands, and 
more provide habitat to a wide range of species, in some cases year-
round and in other cases at particular times as species migrate from 
one region to another. These regions are breeding grounds for fish and 
fowl, and those, including humans, that live off of them. The 
particular conditions each species needs results from the balance 
between the saline ocean waters and the terrestrial freshwaters, all 
mixed by the tides and ocean currents and moderated and mixed by the 
particular weather conditions ranging from mild sea breezes to raging 
storms. Nutrients are provided by the oceanic and river flows and by 
atmospheric deposition, all then cycled through by the chain of living 
plants and animals (including both terrestrial and marine life). 
Productivity has been able to develop as a result of the relative 
stability of the shoreline environment, with niches being filled to 
make optimal use of available resources.
    Climate change is not the only stress that is now being imposed on 
this environment. Harvesting, air and water pollution, encroachment, 
toxics, excessive nitrogen deposition, oxygen deprivation, and more are 
all creating stresses, and now comes sea level rise and climate change 
(i.e., warming, changes in precipitation that alter runoff, intensified 
storms, changes in winds and ocean currents, and more). Sea level has 
been roughly stable for the past several thousand years, yet has 
recently begun to rise. Warming of ocean waters (which leads to their 
expansion, just as mercury expands to fill a thermometer as the 
temperature increases) and water added to the ocean, likely mostly from 
melting of mountain glaciers, caused global sea level to rise 4-8 
inches (10-20 cm) during the 20th century.\49\ For the 21st century, 
the early projections have been that sea level will go up by another 
12-20 inches (30-50 cm); \50\ with the apparent acceleration in the 
melting of the Greenland Ice Sheet that has been observed,\51\ the 
Arctic Climate Impact Assessment concluded that projections of sea 
level rise for the 21st century could quite possibly exceed 20 inches 
(50 cm), reaching toward the upper limit of the IPCC projections. What 
is particularly problematic is that the factors contributing the most 
to sea level rise, namely thermal expansion and the ultimate melting of 
the Greenland and West Antarctic Ice Sheets, are likely to continue to 
contribute to sea level rise for centuries after the rise in greenhouse 
gases is halted, meaning that significant areas of the shoreline will 
be inundated and lost over coming decades and centuries, and that 
protection of the most valuable regions through levee construction 
needs to receive early attention.\52\ To date, no nation has prepared 
for sea level rise of a meter or more within a century, but the 
possibility warrants appropriate planning beyond normal disaster 
    While the rise in sea level itself might seem small, when amplified 
by the effects of storms creating waves and storm surges, the situation 
is particularly threatening. In the Arctic, the melting away from the 
shore of the sea ice away has allowed winter waves to pound the barrier 
islands, causing significant erosion. This is particularly a problem 
because coastal regions are where many native communities have been 
located, often for thousands of years, in order to harvest the bounty 
of both the land and the ocean. The most endangered community is 
currently Shishmaref, which is being eroded away so rapidly that 
community relocation has already started. As the Government 
Accountability Office has projected,\53\ relocation of all the 
endangered villages is going to be very costly. Both the climate 
changes themselves and the relocations will lead to substantial 
disruption of subsistence harvesting \54\ and indigenous culture and 
traditions that have sustained these communities through thousands of 
    For coastal regions exposed to hurricanes and the waves and the 
storm surges that they create, the danger is also very great. While 
international assessments have generally suggested that developing 
countries are more vulnerable to global warming than developed nations 
because they lack the resources to be able to adapt, the developed 
nations have at risk far greater investments in coastal infrastructure, 
including roads, highways, railroads, airports, ports, sewage treatment 
facilities, and residential and commercial buildings. Many of these 
structures are fully exposed to the oceans, unlike New Orleans, which 
at least at one time was protected by extensive wetlands. With the 
power and duration of intense hurricanes observed to be increasing, and 
with greater changes likely ahead as ocean temperatures continue to 
rise, the coastal region is particularly at risk. While building levees 
is likely to be able to work for a while, if sea level rise reaches a 
few meters within a few centuries, retreat is ultimately going to be 
required in many regions. Disrupted coastlines are also likely to 
disrupt the resident and migrating wildlife. While some new wetlands 
may be formed further inland, it is unlikely that such new areas will 
be as extensive or as able to fill the many roles of existing areas, 
especially as the process of coastal inundation will be continuous 
rather than allowing full development at some altered, but fixed, 
change in sea level.
Summary and Concluding Thoughts
    While the discussion above has focused on the great variety of 
changes and interactions that the increase in the CO2 
concentration and changes in climate are leading to (and the above list 
is only a sampling), what will be experienced by the environment and 
society will be all of these changes together, plus the impacts of all 
of the other changes going on, ranging from air and water pollution to 
resource utilization and land cover change. While a number of these can 
be (and are being) ameliorated by regulations and policy, climate 
change presents several unique aspects. First, climate change will keep 
growing and growing--it is an influence that can only be slowed, not 
reversed (at least in any reasonable time horizon). Second, it is fully 
global, and because the world is environmentally and economically 
interconnected, impacts in one location can create impacts in other 
locations. And third, the changes are larger and occurring more rapidly 
than can be accounted for using any analogs to the past, making very 
real the potential for surprises, unexpected changes, unidentified 
thresholds, and tipping points. As Australian author and scientist 
Barrie Pittock has put it, ``Uncertainty is inevitable, but risk is 
certain.'' \55\
    For the natural world, change is already evident. Analyses by 
Parmesan and Yohe (2003) indicate with very high confidence that a 
large fraction of the plant and animal species studied are showing a 
response consistent with that expected to result from changes in 
climate.\56\ The types of responses include shifts in range (e.g., the 
Inuits are spotting types of birds never seen before that far north), 
changes in number and vitality (e.g., the polar bear population around 
Hudson's Bay), and unprecedented susceptibilities (e.g., to pest 
outbreaks). There is no question that the natural world is changing, 
and the main question is how much change can occur before changes in 
keystone species begin to cause the collapse of ecosystems (e.g., of 
the Amazon rainforest \57\) and significant reductions in the ecosystem 
services (e.g., air and water purification, food and fiber generation, 
fish and shrimp production) that these systems provide to society. Of 
particular concern are how all of these changes affect migrating 
species from birds to butterflies and fish to whales, for they have 
generally developed a dependence on a timeline of resources at 
particular locations in order to survive, and significant loss could 
occur from substantial disruption of any of them.
    While modern society may seem less dependent on the natural world, 
many linkages remain, not only between communities and nearby 
ecosystems, but also with conditions around the world. Increased 
temperatures (along with higher absolute humidity--so much higher heat 
indices) will stress those not able to stay in and pay for air-
conditioned space. While those in colder climates that have tight 
houses can readily transfer savings on heating bills to pay for 
increased cooling, those in more open homes in presently southern 
climates will have to invest in considerable structural upgrading to 
make air-conditioning a viable remedy. That the cost of upgrading will 
be high, and the need for it greatest among the poor, will create a 
serious issue of equity, with the least fortunate responsible for the 
lowest energy use yet suffering the largest consequences.
    The effects will not only be personal. Not only do modern societies 
draw resources and food from ecosystems and countries around the world, 
but products also come from around the world and investment portfolios 
typically include a mix of international stocks, coupling one's 
economic state to the state of the world. In addition, with people 
traveling extensively for business and pleasure, the health of people 
around the world is interconnected, and what happens in one location 
can soon affect those in other locations. In that warm conditions are 
generally more favorable for the presence of disease vectors such as 
mosquitoes, warming will lead to the loss of the ally of freezing 
conditions for helping to control mosquito populations. As a result, 
except in regions (such as the U.S.) where rigorous public health 
practices and community building standards have over time separated the 
disease from the disease vector and from people, warming and increased 
precipitation are likely to exacerbate the likelihood of exposure to 
disease vectors.\58\ Even in countries such as the U.S., isolated 
occurrences are likely given the magnitude of international travel, and 
so extra resources will have to be devoted to maintaining high 
standards and quickly addressing new infestations (e.g., by spraying 
for mosquitoes). Changes in the distribution and level of activity of 
various plant species can also exacerbate health problems, as for 
example the increased production of pollen that can exacerbate 
incidence of asthma.\59\
    The shifting climatic patterns and rising sea level are likely to 
be most problematic for small countries and other similarly sized 
entities. For island nations made up mainly of coral atolls, rising sea 
level and higher storm surges are already having deleterious effects on 
aquifers, and continuing sea level rise is likely to inundate several 
island nations over the coming century. For small countries, especially 
those that have focused on growing a particular crop, shifting climatic 
patterns are likely to require changes in crop species, which is likely 
to be difficult to compete as there will likely be the need to break 
into new markets. Whereas many indigenous peoples, including the 
American Indian, have long traditions of adaptation, at the root of 
previous successes was often the ability to relocate; with tribal 
reservations now fixed, community relocation is no longer possible, and 
medicinal plants and other historic species are likely to shift to 
quite removed locations, negating the passed on ecological wisdom 
developed over so many generations.
    For many regions, changes in water resources will be the most 
important effect, with increased competition for reduced resources 
among agricultural, community, industrial and ecological interests. For 
coastal regions, sea level rise and increases in storm intensity will 
pose the most important threats, requiring both enhancement of 
resilience in the near-term and possible relocation in the long-term. 
For those in urban areas, the increased likelihood of heat stress 
conditions and higher air pollution levels \60\ may well pose the most 
significant threat. Because the particular situation of each region 
will depend on its individual circumstances, as indicated in Table 1, 
it is vital that the Nation have an ongoing assessment activity that 
helps regions and sectors to understand, prepare for, and ameliorate 
the most deleterious circumstances. Such an effort, as is called for in 
the Global Change Research Act of 1990 [Pub.L. 101-606], was begun in 
earnest in 1997 with the undertaking of the U.S. National Assessment; 
that this effort was essentially terminated in 2001 after having made 
significant progress in involving stakeholders in regional activities 
has been most unfortunate.
    What is most clear is that global climate change is underway and 
that the risk of adverse consequences for both marine and terrestrial 
environments is quite high. While it will take substantial efforts and 
many decades to limit emissions of greenhouse gases and bring climate 
change to a stop as called for in the U.N. Framework Convention on 
Climate Change ratified by the U.S. Senate in 1992, that virtually no 
effort is being made by the U.S. to accomplish this in the face of all 
the scientific information about impacts is most unfortunate. For the 
people of the Arctic and of the U.S. whom I have had the privilege of 
representing in assessment activities, I urge your most urgent 
consideration of a national effort to prepare for the inevitable 
climate change that lies ahead and to take actions to sharply limit the 
climate change that will be brought on by future emissions.
Websites of Particular Relevance to Understanding of Climate Impacts
    U.S. National Assessment of the Potential Consequences of Climate 
Variability and Change (http://www.usgcrp.gov/usgcrp/nacc/default.htm)

    Arctic Climate Impact Assessment (http://www.acia.uaf.edu/)

    Intergovernmental Panel on Climate Change: (http://www.ipcc.ch/)

    Millennium Ecosystem Assessment: (http://

    Climate Institute (http://www.climate.org/CI/index.shtml)

  Table 1: Examples of important climate change consequences affecting
                          regions of the U.S.*
                           Examples of Key Consequences Affecting:
    Regions and    -----------------------------------------------------
    Subregions        the Environment     the Economy     People's Lives
Northeast--New      Northward shifts    Reduced          Rising
 England and         in the ranges of    opportunities    summertime
 upstate NY,         plant and animal    for winter       heat index
 Metropolitan NY,    species (e.g., of   recreation       will make
 Mid-Atlantic        colorful maples);   such as          cities less
                     Coastal wetlands    skiing;          comfortable
                     inundated by sea-   increased        and require
                     level rise.         opportunities    more use of
                                         for warm-        air-
                                         season           conditioning;
                                         recreation       Reduced snow
                                         such as hiking   cover.
                                         and camping;
                                         will need to
                                         be buttressed.
Southeast--Central  Increased loss of   Increased        Increased
 and Southern        barrier islands     productivity     flooding along
 Appalachians,       and wetlands,       of hardwood      coastlines,
 Gulf Coast,         affecting coastal   forests, with    with increased
 Southeast           ecosystems;         northward        threat from
                     Changing forest     shift of         storms; Longer
                     character, with     timber           period of high
                     possibly greater    harvesting;      heat index,
                     fire and pest       Increased        forcing more
                     threat.             intensity of     indoor living.
                                         coastal storms
Midwest--Eastern    Higher lake and     Increasing       Lowered lake
 Midwest, Great      river               agricultural     and river
 Lakes               temperatures        productivity     levels,
                     cause trend in      in many          impacting
                     fish populations    regions,         recreation
                     away from trout     ensuring         opportunities;
                     toward bass and     overall food     Higher
                     catfish.            supplies but     summertime
                                         possibly         heat index
                                         lowering         reduces urban
                                         commodity        quality of
                                         prices.          life.
Great Plains--      Rising wintertime   Increasing       Altered and
 Northern,           temperatures        agricultural     intensified
 Central,            allow increasing    productivity     patterns of
 Southern,           presence of         in north, more   climatic
 Southwest/Rio       invasive plant      stressed in      extremes,
 Grande Basin        species,            the south;       especially in
                     affecting           Summertime       summer;
                     wetlands and        water            Intensified
                     other natural       shortages        springtime
                     areas; Disruption   become more      flood and
                     of migration        frequent.        summertime
                     routes and                           drought
                     resources.                           cycles.
West--California,   Changes in natural  Rising           Shifts toward
 Rocky Mountains/    ecosystems as a     wintertime       more warm
 Great Basin,        result of higher    snowline leads   season
 Southwest/          temperatures and    to earlier       recreation
 Colorado River      possibly            runoff,          activities
 Basin               intensified         stressing some   (e.g., hiking
                     winter rains.       reservoir        instead of
                                         systems;         skiing);
                                         Increased crop   Greater fire
                                         yields, but      potential
                                         with need for    created by
                                         greater          more winter
                                         controls of      rains and dry
                                         weeds and        summers;
                                         pests.           Enhanced
Pacific Northwest   Added stress to     Earlier winter   Reduced
                     salmon              runoff will      wintertime
                     populations due     limit water      snow pack will
                     to warmer waters    availability     reduce
                     and changing        during warm      opportunities
                     runoff patterns.    season; Rising   for skiing,
                                         forest           increase
                                         productivity.    opportunities
                                                          for hiking;
Alaska              Forest disruption   Damage to        Retreating sea
                     due to warming      infrastructure   ice and
                     and increased       due to           earlier
                     pest outbreaks;     permafrost       snowmelt alter
                     Reduced sea ice     melting;         traditional
                     and general         Disruption of    life patterns;
                     warming disrupts    plant and        Opportunities
                     polar bears,        animal           for warm
                     marine mammals,     resources        season
                     and other           supporting       activities
                     wildlife.           subsistence      increase.
Coastal and         Increased stress    Increased        Intensification
 Islands--Pacific    on natural          pressure on      of flood and
 Islands, South      biodiversity as     water            landslide-
 Atlantic Coast      pressures from      resources        inducing
 and Caribbean       invasive species    needed for       precipitation
                     increase;           industry,        during
                     Deterioration of    tourism and      tropical
                     coral reefs.        communities      storms; More
                                         due to           extreme year-
                                         climatic         to-year
                                         fluctuations,    fluctuations
                                         storms, and      in the
                                         saltwater        climate.
                                         intrusion into
Native People and   Shifts in           The shifting     Disruption of
 Homelands           ecosystems will     climate will     the religious
                     disrupt access to   affect           and cultural
                     medicinal plants    tourism, water   interconnectio
                     and cultural        rights, and      ns of Native
                     resources.          income from      people and the
                                         use of natural   environment.
* MacCracken, M. C., 2001: Climate Change and the U.S. National
  Assessment, pp. 40-43 in McGraw Hill Yearbook of Science and
  Technology 2002, McGraw-Hill, New York, 457 pp.

    Attachment 1: Arctic Temperature Change--Over the Past 100 years

        Released June 28, 2005 by Gordon McBean, Lead author of Chapter 
        2, ACIA Report. The authors of Chapter 2 are: G. A. McBean, G. 
        Alekseev, D. Chen, E. Forland, J. Fyfe, P.Y. Groisman, R. King, 
        H. Melling, R. Vose and P. H. Whitfield.

    This note has been prepared in response to questions and comments 
that have arisen since the publication of the Arctic Climate Impact 
Assessment overview document--``Impacts of a Warming Arctic.'' It is 
intended to provide clarity regarding some aspects relative to the 
material from Chapter 2 Arctic Climate--Past and Present that will 
appear in full with the publication of the ACIA scientific report in 
    The authors of Chapter 2 began their work in 2000. It was 
recognized that the observational data base for the Arctic is limited, 
with few long-term stations and a paucity of observations in general. 
Because at that time the published literature on Arctic temperature 
changes was not comprehensive nor up-to-date, it was decided to 
undertake a new set of calculations, based only on data sets that were 
fully documented in the literature, but updated to the present, using 
the documented procedures. The Global Historical Climatology Network 
(GHCN) data base (updated from Peterson and Vose, 1997) was selected 
for this analysis. A comparison was made with the Climatic Research 
Unit (CRU) data base (Jones and Moberg, 2003) because both data bases 
were used in the Third Assessment Report (IPCC, 2001b) to summarize the 
patterns of temperature change over global land areas since the late 
19th century. The GHCN dataset includes selected quality controlled 
long-term stations suitable for climate change studies. The U.S. 
National Climate Data Center was asked to do the calculations since 
they had both datasets in their archives.
    There are several possible definitions of the Arctic depending on, 
for example, tree line, permanent permafrost, and other factors. It was 
decided for purposes of this analysis that the latitude 60+N would be 
defined as the southern boundary. Although somewhat arbitrary, this is 
no more arbitrary than choosing 62+N, 67+N or any other latitude. Since 
the marine data in the Arctic are very limited in geographical and 
temporal coverage, it was decided, for consistency, to only use data 
from land stations.
    The analysis showed that the annual land-surface air temperature 
variations in the Arctic (north of 60+N) from 1900 to 2002 using the 
GHCN and the CRU datasets led to virtually identical time series, and 
both documented a statistically significant warming trend of 0.09 +C/
decade during that period (Figure 1). Annual land-surface air 
temperature trends were calculated for the periods 1900-2003, 1900-
1945, 1946-1965, and 1966-2003. Trends were calculated from annually 
averaged gridded anomalies using the method of Peterson et al. (1999) 
with the requirement that annual anomalies include a minimum of 10 22 
months of data. For the period 1900-2003, trends were calculated only 
for those 5+ x 5+ grid boxes containing annual anomalies in at least 70 
of the 104 years. The minimum number of years required for the shorter 
time periods (1900-1945, 1946-1965, and 1966-2003) was 31, 14, and 26, 

        Figure 1. Annual anomalies of landsurface air temperature (+C) 
        from 60-90+N for the period 1900-2002. Anomalies are relative 
        to a 1961-90 base period. The smoothed curve was created using 
        a 21-point binomial filter giving near decadal averages. Panel 
        (a)(upper) depicts the GHCN time series (updated from Peterson 
        and Vose, 1997), and panel (b)(lower) depicts the CRU time 
        series (Jones and Moberg, 2003).

    In response to critical comments about the ACIA analysis of the 
temperature record, it is important to note that the choice to use the 
CHCN dataset was made before the analysis was done, before the Polyakov 
et al. (2002) paper was published and based on the logical arguments 
that it was the most comprehensive land-station data base available and 
was well documented in the literature. As noted, the other well-
documented data base, of the CRU, gave virtually identical results.
    It needs to be stressed that the spatial coverage of the region 
north of 60+ N is quite varied. During the period (1900-1945), there 
are 7 grid boxes meeting the requirement of 31 years of data in the 
Alaska/Canadian Arctic/West Greenland sector. The largest number of 
grid boxes is in the North Atlantic sector (East Greenland/Iceland/
Scandinavia) with 13 grid boxes. There were 10 grid boxes over Russia. 
The coverage for periods since 1945 is more uniform. Based on these 
analyses, the annual land-surface air 23 temperature (+C) from 60-90+N, 
smoothed with a 21-point binomial filter giving near decadal averages, 
were warmer in the most recent decade (1990s) than they were in the 
1930-1940s period.
    The analysis of Polyakov et al. (2002) showed the 1930-1940s period 
warmer than the most recent decade. They used individual stations and 
the distributions of stations, according to the Figure 1 in their 
paper, was quite varied for different time periods. The total number of 
stations of more than 65 years is 8 stations in the Alaska/Canada/West 
Greenland sector compared to 43 stations in the North Atlantic/Russian 
sector. Over the whole period of record, their analysis considered 18 
stations for the Alaska/Canada/West Greenland sector compared with 50 
stations from the North Atlantic/Russian sector. The Polyakov paper 
also considered only maritime (or coastal) stations north of 62+N, 
while the analysis presented in Chapter 2 of the ACIA report considered 
all land stations north of 60+N. It should be noted that several of the 
locations of greatest warming in recent decades are apparent as a 
result of the continental stations between 60+ and 62+N (in Russia, 
Canada and Alaska).
    Another important paper is that of Johannessen et al. (2004) who 
found, with a dataset extensively augmented by Russian station data not 
previously available, that the ``early warming trend in the Arctic was 
nearly as large as the warming trend for the last 20 years'' but 
``spatial comparison of these periods reveals key differences in their 
patterns''. Their analysis, consistent with the analysis presented in 
the ACIA Chapter 2, showed that average annual temperatures were higher 
in the most recent decade than in the 1930-1940 period. Further, the 
pattern of temperature increases over the past few decades, they note, 
is different and more extensive than the pattern of temperature 
increases during the 1930s and 1940s, when there was weak (compared to 
the present) lower-latitude warming.
    Chapter 3 of the ACIA report, entitled ``The Changing Arctic: 
Indigenous Perspectives'' documents the traditional knowledge of Arctic 
residents and indicates that substantial changes have already occurred 
in the Arctic and supports the evidence that the most recent decade is 
different from those of earlier in the 20th century.
    Although all data bases suffer from a lack of data in the Alaska/
Canada/West Greenland sector except for the last 50 years, Polyakov et 
al. (2002), ACIA Chapter 2, Johannessen et al. (2004), Serreze, et al. 
(2000) and other analyses all show that the recent decades are warm 
relative to at least most of the period of instrumental record.
    The rate of warming in the recent decades is also much greater than 
the average over the past 100 years (Figure 2). Least-squares linear 
trends in annual anomalies of arctic (60+ to 90+ N) land-surface air 
temperature from the GHCN (updated from Peterson and Vose, 1997) and 
CRU (Jones and Moberg, 2003) datasets for the period 1966-2002 both 
gave warming rates of 0.38 (+C/decade). This is consistent with the 
analysis of Polyakov et al. (2002) and confirmed with satellite 
observations over the whole Arctic, for the past 2 decades (Comiso, 

        Figure 2. Trends in land-surface air temperatures (solid lines) 
        and their 95 percent significance levels (dashed lines) over 
        the past 120 years for (a) 60+ to 90+ N and (b) 0 to 60+ N 
        (data from the GHCN dataset, updated from Peterson and Vose, 

    The modeling studies Johannessen et al. (2004) showed the 
importance of anthropogenic forcing over the past half century for 
modeling the arctic climate. ``It is suggested strongly that whereas 
the earlier warming was natural internal climate-system variability, 
the recent SAT (surface air temperature) changes are a response to 
anthropogenic forcing''. A new paper, published after completion of the 
ACIA Chapter, by Bengtsson et al. (2004) states in its summary, with 
reference to the warming of the 1930-1940s: ``This study suggests that 
natural variability is a likely cause . . .''
    As stated by the IPCC (2001b), model experiments show ``a maximum 
warming in the high latitudes of the Northern Hemisphere''. In 
reference to warming at the global scale, the IPCC (2001a) also 
concluded, ``There is new and stronger evidence that most of the 
warming observed over the past 50 years is attributable to human 
activities''. Karoly et al. (2003) concluded that temperature 
variations in North America during the second half of the 20th century 
were probably not due to natural variability alone. Zwiers and Zhang 
(2003) were able to detect the combined effect of changes in greenhouse 
gases and sulfate aerosols over both Eurasia and North America for this 
period, as did Stott et al. (2003) for 25 northern Asia (50-70+ N) and 
northern North America (50-85+ N). In any regional attribution study 
for the Arctic (which has not yet been published), the importance of 
variability must be recognized. In climate model simulations, the 
arctic signal resulting from human-induced warming is large but the 
variability (noise) is also large. Hence, the signal to noise ratio may 
be lower in the Arctic than at lower latitudes. In the Arctic, data 
scarcity is another important issue. However, it is implausible to 
conclude that the warming of the recent decades is not of anthropogenic 
    In the context of this report, the authors agreed on the following 
terminology. A conclusion termed as ``very probable'' is to be 
interpreted that the authors were 90-99 percent confident in the 
conclusion. The term ``probable'' conveys a 66-90 percent confidence.
    The conclusions of Chapter 2 were that:

        ``Based on the analysis of the climate of the 20th century, it 
        is very probable that the Arctic has warmed over the past 
        century, although the warming has not been uniform. Land 
        stations north of 60+ N indicate that the average surface 
        temperature increased by approximately 0.09 +C/decade during 
        the past century, which is greater than the 0.06 +C/decade 
        increase averaged over the Northern Hemisphere. It is not 
        possible to be certain of the variation in mean land-station 
        temperature over the first half of the 20th century because of 
        a scarcity of observations across the Arctic before about 1950. 
        However, it is probable that the past decade was warmer than 
        any other in the period of the instrumental record.''

    Polar amplification refers to the relative rates of warming in the 
Arctic versus other latitude bands. Using comparable data sets (the 
GHCN dataset), the warming for land stations over the region north of 
60+N, is almost double that for stations in the latitude bands 0-60+N 
(Figure 2). The conclusions of Chapter 2 were that:

        ``Evidence of polar amplification depends on the timescale of 
        examination. Over the past 100 years, it is possible that there 
        has been polar amplification, however, over the past 50 years 
        it is probable that polar amplification has occurred.''

Bengtsson, L., V.A. Semenov and O.L. Johannssen, 2004; The early 
            twentieth-century warming in the Arctic--a possible 
            mechanism. J. Climate, 17, 4045-4057.
Comiso, J., 2003. Warming trends in the Arctic from clear sky satellite 
            observations. Journal of Climate, 16:3498-3510.
IPCC, 2001a. Climate Change 2001: Synthesis Report. A Contribution of 
            Working Groups I, II, and III to the Third Assessment 
            Report of the Intergovernmental Panel on Climate Change. 
            Watson, R.T., and the Core Writing Team (eds.). Cambridge 
            University Press, 398 pp.
IPCC, 2001b. Climate Change 2001: The Scientific Basis. Contribution of 
            Working Group I to the Third Assessment Report of the 
            Intergovernmental Panel on Climate Change. Houghton, J.T., 
            Y. Ding, D.J. Griggs, M. Noguer, P.J. van der Linden, X. 
            Dai, K. Maskell and C.A. Johnson (eds.) Cambridge 
            University Press, 881 pp.
Johannessen, O.M., L. Bengtsson, M.W. Miles, S.I. Kuzmina, V.A. 
            Semenov, G.V. Alekseev, A.P. Nagurnyi, V.F. Zakharov, L.P. 
            Bobylev, L.H. Pettersson, K. Hasselmann and H.P. Cattle, 
            2004. Arctic climate change: observed and modelled 
            temperature and sea-ice variability. Tellus A, 56:328-341.
Jones, P.D. and A. Moberg, 2003. Hemispheric and large-scale surface 
            air temperature variations: an extensive revision and an 
            update to 2001. Journal of Climate, 16:206-223.
Karoly, D.J., K. Braganza, P.A. Stott, J.M. Arblaster, G.A. Meehl, A.J. 
            Broccoli and K.W. Dixon, 2003. Detection of a human 
            influence on North American climate. Science, 302:1200-
Peterson, T.C. and R.S. Vose, 1997. An overview of the Global 
            Historical Climatology Network temperature data base. 
            Bulletin of the American Meteorological Society, 78:2837-
Peterson, T.C., K.P. Gallo, J. Livermore, T.W. Owen, A. Huang and D.A. 
            McKittrick, 1999. Global rural temperature trends. 
            Geophysical Research Letters, 26:329-332.
Polyakov, I.V., G.V. Alekseev, R.V. Bekryaev, U. Bhatt, R.L. Colony, 
            M.A. Johnson, V.P. Karklin, A.P. Makshtas, D. Walsh and 
            A.V. Yulin, 2002. Observationally based assessment of polar 
            amplification of global warming. Geophysical Research 
            Letters, 29(18):1878.
Serreze, M.C., J.E. Walsh, F.S. Chapin III, T. Osterkamp, M. Dyurgerov, 
            V. Romanovsky, W.C. Oechel, J. Morison, T. Zhang and R.G. 
            Barry, 2000. Observational evidence of recent change in the 
            northern high latitude environment. Climatic Change, 
Stott, P.A., G.S. Jones and J.F.B. Mitchell, 2003. Do models 
            underestimate the solar contribution to recent climate 
            change? Journal of Climate, 16:4079-4093.
Zwiers, F.W. and X. Zhang, 2003. Toward regional climate change 
            detection. Journal of Climate, 16:793-797.
    \1\ Prepared in cooperation with Dr. Michael MacCracken, chief 
scientist for climate change programs at the Climate Institute, 
Washington DC, and Dr. Rosina Bierbaum, Dean of the School of Natural 
Resources and Environment at the University of Michigan in Ann Arbor.
    \2\ National Assessment Synthesis Team, 2000: Climate Change 
Impacts on the United States: The Potential Consequences of Climate 
Variability and Change: Overview Report, U. S. Global Change Research 
Program, Cambridge University Press, Cambridge UK, 154 pp.
    [Also see Foundation Report, U.S. Global Change Research Program, 
Cambridge University Press, Cambridge UK, 612 pp. published in 2001]. 
The most significant results of the National Assessment were summarized 
in the U.S. Climate Action Report--2002, which was submitted to the 
U.N. under the Framework Convention on Climate Change as the Third 
National Communication of the United States of America (thus 
representing the official position of the U.S. Government in a document 
formally approved by all of the involved agencies and departments); 
this document is available from the U.S. Government Printing Office 
website at http://bookstore.gpo.gov and is posted at http://
    \3\ Arctic Climate Impact Assessment (ACIA), 2004: Impacts of a 
Warming Arctic: Arctic Climate Impact Assessment, Cambridge University 
Press, 140 pp. [Also see ACIA, 2005, Cambridge University Press, 1042 
    \4\ The Arctic Council was established on September 19th, 1996 in 
Ottawa, Canada. The Arctic Council is a high-level intergovernmental 
forum that provides a mechanism to address the common concerns and 
challenges faced by the Arctic governments and the people of the Arctic 
as a means of improving the economic, social and cultural well being of 
the north. The national members of the Council are Canada, Denmark, 
Finland, Iceland, Norway, the Russian Federation, Sweden, and the 
United States of America; the Association of Indigenous Minorities of 
the North, Siberia and the Far East of the Russian Federation, the 
Inuit Circumpolar Conference, the Saami Council, the Aleutian 
International Association, Arctic Athabaskan Council and Gwich'in 
Council International are Permanent Participants in the Council. Many 
additional entities participate through a provision that provides for 
non-arctic states, inter-governmental and inter-parliamentary 
organizations and nongovernmental organizations to become involved as 
Official Observers.
    \5\ The International Arctic Sciences Committee (IASC) was founded 
28 August 1990 by national science organizations representing all of 
the arctic countries. It provides the major venue for national science 
organizations, mostly academies of science, to facilitate and foster 
cooperation in all fields of arctic research. IASC currently has 
participation by scientists from Canada, China, Denmark, Finland, 
France, Germany, Iceland, Italy, Japan, The Netherlands, Norway, 
Poland, Republic of Korea, Russia, Sweden, Switzerland, United Kingdom, 
and the United States.
    \6\ The IPCC's assessments are all published by Cambridge 
University Press, and are also available over the Internet at http://
www.ipcc.ch. IPCC's Fourth Impact Assessment Report is due to be 
completed in 2007.
    \7\ IPCC, 2001: Climate Change 2001: The Scientific Basis, edited 
by J. T. Houghton et al., Cambridge University Press, 881 pp., see also 
    \8\ For example, see http://data.giss.nasa.gov/gistemp/2005/. 
Results of other centers give similar results.
    \9\ Such reconstructions estimate past values of surface 
temperature using tree-rings, coral growth patterns, changes in 
vegetation indicated by changes in pollen preserved in lake sediments, 
    \10\ For example, see Mann, M. E., and P. D. Jones, 2003: Global 
surface temperatures over the past two millennia. Geophysical Research 
Letters 30, 1820-1824, doi. 10.1029/2003 GL017814. Controversies over 
the findings reported in this initial paper have largely been addressed 
over the years since it was published.
    \11\ See Attachment 1 for an overview by the authors of ACIA's 
chapter on past climate change regarding the unprecedented patterns of 
modern warming and reconciling this finding with the analyses of 
supposed similarly warm conditions in the early to mid-20th century.
    \12\ The near final draft of a tightly focused assessment by the 
U.S. Climate Change Science Program (see http://www.climatescience.gov/
Library/sap/sap1-1/third-draft/default.htm) of trends in surface and 
upper troposphere temperatures indicates that previous criticisms that 
warming rates have been significantly different are not valid. This 
focused assessment reports near resolution of this issue as a result of 
studies that have identified corrections needed in satellite and 
balloon records as a result of instrument and observational factors.
    \13\ These estimates allow for uncertainties in projections of 
future energy-related emissions. However, two other factors can also 
introduce uncertainties. First, present models have only a limited 
treatment of the processes that govern how rapidly CO2 will 
be taken up by the land and ocean carbon reservoirs; preliminary 
studies by Cox et al. (Cox, P.M., R.A. Betts, C.D. Jones, S.A. Spall, 
and I.J. Totterdell, 2000: Acceleration of global warming due to carbon 
cycle feedbacks in a coupled climate model, Nature, 408, 184-187) and 
Fung et al. (Fung, I., S.C. Doney, K. Lindsay, and J. John, 2005: 
Evolution of carbon sinks in a changing climate, Proceedings of the 
National Academy of Sciences (USA), 102, 11201-11206, doi:10.1073/
pnas.0504949102) indicate that current models are overestimating the 
amount of carbon that can be taken up, thus leading to small 
underestimates of the rate of warming. Second, limits in our estimates 
of how the climate will respond to changing atmospheric composition are 
estimated to have the potential to increase or decrease the temperature 
changes in 2050 by about 0.3+C (roughly 0.5+F) and in 2100 by about 
twice this amount, with the likelihood (as a result of recent studies 
of the likely effects of sulfate aerosols) that the change could be 
greater than estimated more likely than that these are overestimates.
    \14\ ppmv stands for parts per million by volume, or number of 
CO2 molecules per million molecules of air.
    \15\ See Doney, S.C., 2006: The dangers of ocean acidification, 
Scientific American, 294(3), March 2006, 58-65; and Ocean Acidification 
Due to Increasing Atmospheric Carbon Dioxide, Royal Society, 2005. 
Available at http://www.royalsoc.ac.uk/displaypagedoc.asp?id=13314.
    \16\ See Kleypas, J. A., R. W. Buddemeier, D. Archer, J-P. Gattuso, 
C. Langdon, and B. N. Opdyke, 1999: Geochemical consequences of 
increased atmospheric carbon dioxide on coral reefs, Science, 284, 118-
120; and Buddemeier, R. W., J. A. Kleypas, and R. B. Aronson, 2004: 
Coral reefs & global climate change: Potential contributions of climate 
change to stresses on coral reef ecosystems, Prepared for the Pew 
Center on Global Climate Change, http://www.pewclimate.org/global-
    \17\ See: Orr, J.C., V.J. Fabry, O. Aumont, L. Bopp, S.C. Doney, 
R.A. Feely, A. Gnanadesikan, N. Gruber, A. Ishida, F. Joos, R.M. Key, 
K. Lindsay, E. Maier-Reimer, R. Matear, P. Monfray, A. Mouchet, R.G. 
Najjar, G.-K. Plattner, K.B. Rodgers, C.L. Sabine, J.L. Sarmiento, R. 
Schlitzer, R.D. Slater, I.J. Totterdell, M.-F. Weirig, Y. Yamanaka, and 
A. Yool, 2005: Anthropogenic ocean acidification over the twenty-first 
century and its impact on marine calcifying organisms, Nature, 437, 
681-686, doi:10.1038/nature04095.
    \18\ Levitus, S., J. I. Antonov, and T. P. Boyer, 2005: Warming of 
the world ocean, 1955-2003, Geophysical Research Letters, 32 (L02604), 
doi: 10.1029/2004GL021592. Levitus et al. find that over 90 percent of 
the energy trapped by the increasing concentrations of greenhouse gases 
ends up in the ocean.
    \19\ Barnett, T. P., D. W. Pierce, K. M. AchutaRao, P. J. Gleckler, 
B. D. Santer, J. M. Gregory, and W. M. Washington, 2005: Penetration of 
human-induced warming into the world's oceans, Science, 309, 284-287.
    \20\ For example, see Webster, P. J., G. J. Holland, J. A. Curry, 
and H.-R. Change, 2005: Changes in tropical cyclone number, duration, 
and intensity in a warming environment, Science, 309, 1844-1846 and 
Emanuel, K. A., 2005: Increasing destructiveness of hurricane intensity 
on climate, Nature, 326, 483-485.
    \21\ Anthes, R. A., R. W. Corell, G. Holland, J. W. Hurrell, M. C. 
MacCracken, and K. E. Trenberth, 2006: Hurricanes and Global Warming--
Potential Linkages and Consequences, Bulletin of the American 
Meteorological Society, 87 (May, in press). With regard to the most 
important limitation in detection studies, it has been the presumption 
by a number of investigators (e.g., Pielke et al., 2005, Bulletin of 
the American Meteorological Society, 86, 1571-1575) that the response 
should be a linear trend in hurricane number (or in other factors) over 
the course of the century that is made dubious by many detection-
attribution studies that indicate that human influences led to a time 
history of Northern Hemisphere temperature change during the 20th 
century consisting of warming early in the century, a slight cooling in 
mid-century (especially in the North Atlantic sector that is key in 
affecting hurricane characteristics), and then a sharp warming since 
the 1970s.
    \22\ Building societal resilience through adaptive efforts could 
include, in the short-term, more effective evacuation, stronger levees, 
beach restoration, enhancing vegetation cover of dunes, strengthening 
of buildings, etc., and longer-term, withdrawal from the most 
vulnerable areas, enhanced building codes, storm surge barriers (e.g., 
being proposed to protect New York harbor), adding capacity to 
evacuation routes, etc.
    \23\ See for example: Sarmiento, J., R. Slater, R .Barber, L. Bopp, 
S.C. Doney, A.C. Hirst, J. Kleypas, R. Matear, U. Mikolajewicz, P. 
Monfray, V. Soldatov, S. Spall, R. Slater, and R. Stouffer, 2004: 
Response of ocean ecosystems to climate warming, Global Biogeochemical 
Cycles, 18, GB3003, doi:10.1029/2003GB002134.
    \24\ For example, see report in the Washington Post, April 15, 2006 
entitled ``Warming Arctic is Taking a Toll,'' which reports on results 
of a scientific study appearing in the journal Aquatic Mammals that 
walrus calves are being found abandoned at sea (and almost certain to 
starve and drown) because there is no longer any sea ice for them to 
rest on in the areas shallow enough for their mothers to feed off the 
    \25\ Policy Document is available at: www.acia.uaf.edu/PDFs/
    \26\ Karnosky, D. F., K. S. Pregitzer, D. R. Zak, M. E. Kubiske, G. 
R. Hendrey, D. Weinstein, M. Nosal, and K. E. Percy, 2005: Scaling 
ozone responses of forest trees to the ecosystem level in a changing 
climate, Plant, Cell, and Environment, 28, 965-981.
    \27\ Reich, P. B., S. E. Hobbie, T. Lee, D. S. Ellsworth, J. B. 
West, D. Tilman, J. M. H. Knops, S. Naeem, and J. Trost, 2006: Nitrogen 
limitation constrains sustainability of ecosystem response to 
CO2, Nature, 440, 922-925.
    \28\ Indeed, a number of studies suggest that, along with 
technology and seed enhancements, the increased CO2 
concentration is already contributing to higher yields.
    \29\ Note, however, that greater year-to-year variability or more 
frequently exceeding various temperature and/or moisture (or dryness) 
thresholds may make optimization to a narrow range of climatic 
variables more risky, and farmers may instead choose not to select seed 
strains that tolerate a wider range of conditions in exchange for 
slightly reduced productivity. A key determinant will be how rapidly 
improvements are made in the skill of seasonal forecasts, a topic on 
which research attention is being closely focused.
    \30\ National Assessment Synthesis Team, 2001: Climate Change 
Impacts on the United States: The Potential Consequences of Climate 
Variability and Change: Foundation, U.S. Global Change Research 
Program, Cambridge University Press, 612 pp. Available at http://
    \31\ Ibid.
    \32\ Breshears, D. D., et al. 2005: Regional vegetation die-off in 
response to global-change-type drought, Proceedings of the National 
Academy of Sciences, 102 (Oct. 18), 15144-15148. Available at http://
    \33\ Emanuel, K., 2005: Increasing destructiveness of tropical 
cyclones over the past 30 years, Nature 436, 686-688.
    \34\ Friedlingstein, P., P. Cox, R. Betts, W. von Bloh, V. Brovkin, 
S. Doney, M. Eby, I. Fung, B. Govindasamy, J. John, C. Jones, F. Joos, 
M. Kawamiya, W. Knorr, K. Lindsay, H.D. Matthews, T. Raddatz, P. 
Rayner, C. Reick, E. Roeckner, K.-G. Schnitzler, R. Schnur, K. 
Strassmann, S. Thompson, A.J. Weaver, and N. Zeng, 2006: Climate-carbon 
cycle feedback analysis; Results from the C4MIP model intercomparison, 
Journal of Climate, in press.
    \35\ See, for example, the Cox et al. and Fung et al. references 
provided above.
    \36\ For comparison, the CO2 increase from preindustrial 
to the present has been about 100 ppmv.
    \37\ Beedlow, P.A., D.T. Tingey, D.L. Phillips, W.E. Hotsett, and 
D.M. Olszyk, 2004: Rising atmospheric CO2 and carbon 
sequestration in forests, Ecological Environment, 2, 315-322.
    \38\ Warmer lake temperatures also mean delayed formation of lake 
ice in the winter, perversely allowing a longer period for lake effects 
storms to dump snow on the surrounding regions.
    \39\ Arctic peoples and the energy industry also depend on the 
frozen ground to enable moving around the Arctic; warming has already 
reduced by about half the number of days the ground is hard enough for 
movement of some oil-drilling equipment.
    \40\ See ``Changes in the Velocity Structure of the Greenland Ice 
Sheet'' by Eric Rignot and Pannir Kanagaratnam, Science Vol 311 17 
February 2006, as well as ``The Greenland Ice Sheet and Global Sea-
Level Rise by Julian A. Dowdeswell, Science Vol 311 17 February 2006, 
and also see Paterson, W.S.B., and N. Reeh, 2001: Thinning of the ice 
sheet in northwest Greenland over the past forty years, Nature, 414, 
    \41\ Note that throughout this process, the temperature of the ice 
surface when out on the banquet table would still be at the freezing 
point, even with an infrared lamp shining on it. What matters is the 
amount of heat being delivered while the temperature is fixed at the 
melting point--not that the temperature has not risen (as some Skeptics 
use as an argument to try to find fault with attributing the 
unprecedented melting back of glaciers to the unprecedented human-
induced increase in greenhouse gas concentrations.
    \42\ See Gregory, J.M., P. Huybrechts, and S.C.B. Raper, 2004: 
Climatology: Threatened loss of the Greenland Ice Sheet, Nature, 428, 
616; doi:10.1038/428616a. The IPCC's Third Assessment Report suggests 
that the time scale for such melting would be millennia, but the recent 
identification of the meltwater runoff mechanism for more rapid melting 
is likely to lead to reductions in the estimates included in future 
    \43\ That such melting occurred is evident by the absence of older 
ice in ice cores drilled in southern Greenland, but the presence of ice 
that old in cores drilled in northern Greenland. Beach horizons on 
remote islands that are located a few meters above present sea level 
appear to confirm that a comparable amount of water (or perhaps even 
more from some loss of the West Antarctic Ice Sheet) had been added to 
the oceans. See ``Paleoclimatic Evidence for Future Ice-Sheet 
Instability and Rapid Sea-Level Rise'' Jonathan T. Overpeck, Bette L. 
Otto-Bliesner, Gifford H. Miller, Daniel R. Muhs, Richard B. Alley, 
Jeffrey T. Kiehl Science 24 March 2006: Vol. 311. no. 5768, pp. 1747-
1750 DOI: 10.1126/science.1115159
    \44\ The very hot European summer of 2003 that led to a month-long 
heat wave that caused the premature deaths of tens of thousands is the 
type of rare event that is estimated to have become much more likely as 
a result of recent warming, and will become even more likely in the 
future (e.g., see Schar, C. et al., 2004: The role of increasing 
temperature variability in European summer heat waves, Nature, 427, 
    \45\ Dai, A., K. E. Trenberth, and T. Qian, 2004: A global dataset 
of Palmer Drought Severity Index for 1870-2002: Relationship with soil 
moisture and effects of surface warming, Journal of Hydrometeorology, 
5, 1117-1130.
    \46\ McKenzie, D., Z. Gedalof, D. L. Peterson, and P. Mote, 2004: 
Climatic change, wildfire, and conservation, Conservation Biology, 18, 
    \47\ Milly, P.C.D., R.T. Wetherald, K.A. Dunne, and T.L. Delworth, 
2002: Increasing risk of great floods in a changing climate, Nature, 
415, 514-17.
    \48\ A large hurricane striking New Orleans is only one example of 
a very damaging event. Other examples identified during the U.S. 
National Assessment included a storm surge into New York harbor, and 
the entire northeast coastline that has been spared strong hurricanes 
for several decades has since become increasingly developed, and 
susceptible to very high damage events.
    \49\ See IPCC Working Group I Third Assessment Report, 2001. Over 
the past few decades, the rate of rise is consistent with a rate that 
exceeds the upper end of this range, indicating that an acceleration in 
the rate may have begun during this period (e.g., see Rignot, E., and 
P. Kanagaratnam, 2005: Changes in the velocity structure of the 
Greenland Ice Sheet, Science, 311, 986-990).
    \50\ The full range for the IPCC estimate is about 4 to 35 inches 
considering the full range of all emissions scenarios and climate 
sensitivities, whereas the central estimate used in the text is for the 
average response across all climate models and emissions scenarios.
    \51\ Although projecting a rather significant buildup of ice on 
East Antarctica, IPCC's Third Assessment Report projected only very 
limited melting of the Greenland and West Antarctic Ice Sheets over the 
21st century. Observations since publication of that report suggest 
that at least the Greenland Ice Sheet is likely to experience 
significant loss of ice as the warming builds up over coming decades.
    \52\ Low levees have already been installed around LaGuardia 
airport due to a severe storm some 50 years ago, and many additional 
areas are at risk. Low lying islands in the Chesapeake Bay have also 
been lost over recent times, more due to natural land subsidence than 
human-induced sea level rise, but providing an insight into the likely 
consequences of an acceleration of the rate of rise due to global 
warming. And the severe loss of coastal wetlands in the Mississippi 
delta region (again due mainly to other factors up to the present) 
provides a telling example of how important the coastal islands are for 
protecting communities.
    \53\ GAO, 2004: Alaska Native Villages: Villages Affected by 
Flooding and Erosion Have Difficulty Qualifying for Federal Assistance, 
Statement of Robert A. Robinson, Managing Director, Natural Resources 
and Environment, GAO-04-895T.
    \54\ It is substantially more difficult to catch a whale or seal by 
chasing it in open waters than by waiting for it to surface at an air 
    \55\ Pittock, A. B., 2005: Climate Change: Turning Up the Heat, 
Earthscan, London, 316 pp.
    \56\ Parmesan, C., and G. Yohe, 2003: A globally coherent 
fingerprint of climate change impacts across natural systems, Nature, 
421, 37-42.
    \57\ For example, see Cox, P.M., R.A. Betts, C.D. Jones, S.A. 
Spall, and I.J. Totterdell, 2000: Acceleration of global warming due to 
carbon cycle feedbacks in a coupled climate model, Nature, 408, 184-
    \58\ For example, see Watson, R.T., J. Patz, D.J. Gubler, E.A. 
Parson, and J. H. Vincent, 2005: Environmental health implications of 
global climate change, Journal of Environmental Monitoring, 7, 834-843, 
and Hunter, P. R., 2003: Climate change and waterborne and vector-borne 
disease, Journal of Applied Microbiology, 94, 37S-46S.
    \59\ Beggs, P.J., and H.J. Bambrick, 2005: Is the global rise of 
asthma and early impact of anthropogenic climate change? Environmental 
Health Perspectives, 113, 915-919.
    \60\ For a given level of pollution, higher temperatures accelerate 
the rate of formation of photochemical smog.

    Senator Vitter. Thank you very much, Doctor.
    And, Dr. Reiter, welcome.


    Dr. Reiter. Thank you, Senator Lautenberg, Senator Stevens, 
Mr. Chairman, Members of the Committee.
    I am a specialist in the natural history and biology of 
mosquitoes, the epidemiology of the diseases they transmit, and 
strategies for their control. I worked, for 22 years, for the 
Centers for Disease Control and Prevention, CDC, including 2 
years as a research scholar at Harvard. I am a member of the 
World Health Organization Expert Advisory Committee on Vector 
Biology and Control. I have directed many entomological 
investigations of outbreaks of mosquito-borne disease and 
others, such as Ebola hemorrhagic fever. I was a lead author of 
the U.S. National Assessment of the Potential Consequences of 
Climate Variability and Change. I'm presently professor of 
medical entomology at the Institut Pasteur, in Paris, France.
    In this presentation, I restrict my comments to my own 
field, to malaria, and I will want to emphasize to you four 
points. First of all, that malaria is not an exclusively 
tropical disease. Second of all, the transmission dynamics of 
the disease are complex, and the interplay of climate, ecology, 
mosquito biology, mosquito behavior, and many other factors 
defies simplistic analysis. It is--third, it is facile to 
attribute the current resurgence of the disease to climate 
change or to use models based on temperature to predict future 
prevalence. And, last, many environmental activists are using 
the ``big talk'' of science to create a simple, but very false, 
paradigm. Specialists, like myself, who protest this paradigm 
are generally ignored or are labeled ``skeptics.''
    In the early 1990s, malaria topped the list of dangerous 
impacts of global warming. The disease was going to move to 
rich countries in the temperate regions as temperatures 
increased. This prediction ignored the fact that malaria was 
once an important cause of morbidity and mortality throughout 
most of the United States and Europe, even in the period that 
our climatology colleagues have called the Little Ice Age. In 
the United States, as in Western Europe, despite a steadily 
warming climate, prevalence of malaria declined in the 19th 
century as a result of multiple changes in agriculture, 
lifestyle that affected the abundance of mosquitoes, their 
contact with people, and the availability of antimalarial 
drugs. Nevertheless, the most catastrophic epidemic of all time 
on record anywhere in the world occurred in the Soviet Union in 
the 1920s, with a peak incidence of 13 million cases per year 
and 600,000 deaths. Transmission was high in many parts of 
Siberia, and there were 30,000 cases and 10,000 deaths in 
Archangel, close to the Arctic Circle. The disease persisted in 
many parts of Europe until the advent of DDT. Clearly here, 
temperature was not a limiting factor in the distribution or 
prevalence of malaria.
    In the mid-1990s, activist emphasis changed to the 
transmission of malaria in poorer countries, often referred to 
as ``those least able to protect themselves,'' particularly in 
sub-Saharan Africa. Yet in most of Africa, temperatures are 
already far above the minimum required for transmission. In 
addition, in most sub-Saharan Africa, transmission is termed 
``stable,'' because people are already exposed to many 
infective bites, sometimes more than 300 per year. So, annual 
incidence is fairly constant. Mortality is highest in the 
newcomers, young children and immigrants. Those that survive 
acquire a partial immunity that reduces the risk of fatal 
    In other regions, transmission is endemic, but termed 
``unstable,'' because annual transmission is variable. In these 
regions, the potential for epidemics is much higher, because 
immunity declines in periods of low transmission. Climatic 
factors, particularly rainfall, are sometimes, but by no means 
always, relevant.
    In recent years, activist emphasis has shifted to highland 
malaria, particularly in East Africa. Despite carefully 
research articles by malaria specialists, there has been a 
flurry of articles by nonspecialists who claim an increase in 
the altitude of malaria transmission that is already 
attributable to warming and quote models that predict further 
increase in the next 50 years. Tellingly, these people rarely, 
if ever, give any detail of the views of specialists who 
challenge them, nor do they mention that maximum altitudes for 
transmission in the period from 1880 until 1945 were 500 to 
1,500 meters higher than in the areas that are quoted as 
examples. And, in any case, highland above 2,000 meters 
constitutes a mere 1.3 percent of the whole continent, an area 
about the size of Poland, totally dwarfed by regions of stable 
and unstable transmission at lower altitudes.
    An exasperating aspect of the debate is that this spurious 
science is endorsed in the public forum by influential panels 
of experts. I refer particularly to the Intergovernmental Panel 
on Climate Change. Every 5 years, this U.N.-based organization 
publishes a consensus of the world's top scientists in all 
aspects of climate change. Quite apart from what we consider to 
be the rather dubious process by which these scientists are 
selected, consensus, sir, is the stuff of politics and not of 
science. Science proceeds by observation, hypothesis, and 
experiment. The complexity of this process and the 
uncertainties involved are a major obstacle to meaningful 
understanding of scientific issues by the lay public. In 
reality, a genuine concern for mankind and the environment 
demands the inquiry, accuracy, and skepticism that are 
intrinsic to authentic science. A public that is unaware of 
this is vulnerable to abuse.
    The current increase in malaria is alarming, but the 
principal factors involved are deforestation, new agricultural 
practices, population increase, urbanization, poverty, civil 
conflict, war, AIDS, resistance to antimalarials, and 
resistance to insecticides. In my opinion, we should give 
priority to a creative and organized effort to stem the 
burgeoning tragedy of uncontrolled malaria, rather than 
worrying about the weather.
    Thank you for the honor of having spoken here.
    [The prepared statement of Dr. Reiter follows:]

           Prepared Statement of Paul Reiter, Chief, Insects 
        and Infectious Disease Unit; Professor, Institut Pasteur
Malaria in the Debate on Climate Change and Mosquito-borne Disease
    I am a specialist in the natural history and biology of mosquitoes, 
the epidemiology of the diseases they transmit, and strategies for 
their control. I worked for 22 years for the Centers for Disease 
Control and Prevention (CDC), including 2 years as a Research Scholar 
at Harvard. I am a member of the World Health Organization Expert 
Advisory Committee on Vector Biology and Control. I have directed many 
investigations of outbreaks of mosquito-borne disease, and of others 
such as Ebola Haemorrhagic Fever. I was a Lead Author of the U.S. 
National Assessment of the Potential Consequences of Climate 
Variability and Change. I am presently Professor of Medical Entomology 
at the Institut Pasteur in Paris, France.
    In this brief presentation I restrict my comments to malaria, and 
emphasize four points:

        1. Malaria is not an exclusively tropical disease.

        2. The transmission dynamics of the disease are complex; the 
        interplay of climate, ecology, mosquito biology, mosquito 
        behavior and many other factors defies simplistic analysis.

        3. It is facile to attribute current resurgence of the disease 
        to climate change, or to use models based on temperature to 
        ``predict'' future prevalence.

        4. Environmental activists use the ``big talk'' of science to 
        create a simple but false paradigm. Malaria specialists who 
        protest this are generally ignored, or labelled as 

    In the early 1990s, malaria topped the list of dangerous impacts of 
global warming; the disease would move to temperate regions as 
temperatures increased. This prediction ignored the fact that malaria 
was once an important cause of morbidity and mortality throughout most 
of the U.S. and Europe, even in a period that climatologists call the 
``Little Ice Age.'' In the US, as in western Europe, prevalence 
declined in the 19th century as a result of multiple changes in 
agriculture and lifestyle that affected the abundance of mosquitoes, 
their contact with people, and the availability of anti-malarial drugs. 
Nevertheless, the most catastrophic epidemic on record anywhere in the 
world occurred in the Soviet Union in the 1920s, with a peak incidence 
of 13 million cases per year, and 600,000 deaths. Transmission was high 
in many parts of Siberia, and there were 30,000 cases and 10,000 deaths 
in Archangel, close to the Arctic circle. The disease persisted in many 
parts of Europe until the advent of DDT. Clearly, temperature was not a 
limiting factor in its distribution or prevalence.
    In the mid-1990s, activist emphasis changed to transmission in 
poorer countries, often referred to as those ``least able to protect 
themselves,'' particularly in sub-Saharan Africa. Yet in most of the 
continent, temperatures are far above the minimum required for 
transmission, and most of sub-Saharan Africa, transmission is termed 
``stable'' because people are exposed to many infective bites, 
sometimes more than 300 per year, so annual incidence is fairly 
constant. Mortality is highest in ``newcomers''--young children and 
immigrants. Those that survive acquire a partial immunity that reduces 
the risk of fatal illness. In other regions, transmission is endemic 
but `unstable' because annual transmission is variable; the potential 
for epidemics is great because immunity declines in periods of low 
transmission. Climatic factors, particularly rainfall, are sometimes--
but by no means always--relevant.
    In recent years, activist emphasis has shifted to ``highland 
malaria,'' particularly in East Africa. Despite carefully researched 
articles by malaria specialists, there has been a flurry of articles by 
non-specialists who claim a recent increase in the altitude of malaria 
transmission attributable to warming, and quote models that ``predict'' 
further increase in the next 50 years. Tellingly, they rarely quote the 
specialists who challenge them. Nor do they mention that maximum 
altitudes for transmission in the period 1880-1945 were 500-1500m 
higher than in the areas that are quoted as examples. Moreover, 
highland above 2000m constitutes a mere 1.3 percent of the whole 
continent, an area about the size of Poland that is totally dwarfed by 
regions of stable and unstable transmission at lower altitudes.
    A galling aspect of the debate is that this spurious ``science'' is 
endorsed in the public forum by influential panels of ``experts.'' I 
refer particularly to the Intergovernmental Panel on Climate Change 
(IPCC). Every 5 years, this UN-based organization publishes a 
`consensus of the world's top scientists' on all aspects of climate 
change. Quite apart from the dubious process by which these scientists 
are selected, such consensus is the stuff of politics, not of science. 
Science proceeds by observation, hypothesis and experiment. The 
complexity of this process, and the uncertainties involved, are a major 
obstacle to meaningful understanding of scientific issues by non-
scientists. In reality, a genuine concern for mankind and the 
environment demands the inquiry, accuracy and skepticism that are 
intrinsic to authentic science. A public that is unaware of this is 
vulnerable to abuse.
    The current increase in malaria is alarming, but the principal 
factors involved are deforestation, new agricultural practices, 
population increase, urbanization, poverty, civil conflict, war, AIDS, 
resistance to anti-malarials, and resistance to insecticides, not 
climate. In my opinion, we should give priority to a creative and 
organized effort to stem the burgeoning tragedy of uncontrolled 
malaria, rather than worrying about the weather.

           The Lancet Infectious Diseases, Vol. 4, June 2004

 Reflection & Reaction--Global Warming and Malaria: a Call for Accuracy

    For more than a decade, malaria has held a prominent place in 
speculations on the impacts of global climate change. Mathematical 
models that ``predict'' increases in the geographic distribution of 
malaria vectors and the prevalence of the disease have received wide 
publicity. Efforts to put the issue into perspective \1\- 
\5\ are rarely quoted and have had little influence on the political 
debate. The model proposed by Frank C Tanser and colleagues \6\ in The 
Lancet and the accompanying Commentary by Simon Hales and Alistair 
Woodward \7\ are typical examples.
    The relation between climate and malaria transmission is complex 
and varies according to location,\2\ yet Tanser et al base their 
projections on thresholds derived from a mere 15 African locations. 
Slight adjustments of values assigned to such thresholds and rules can 
influence spatial predictions strongly.\8\ The authors invest 
considerable effort in assessments of the sensitivity of their model, 
at the expense of defining the internal sensitivities of their 
thresholds and rules. The predictive skill of their model is low (63 
percent sensitivity, 95 percent CI 61-65 percent) but they consider 
projections acceptable if prevalence is projected ``to within a month'' 
(presumably +/- 1 month?), thereby biasing their model toward success. 
A model covering an entire year in a parasite-positive site would 
always be correct, although in such areas it would be relatively 
insensitive to climate. By contrast, sites in which transmission is 
seasonal would provide a more reliable test of accuracy, but estimation 
is more difficult because climate sensitivity is greater. Furthermore, 
because parasite clearance in communities is not instantaneous,\9\ spot 
samples of parasitaemia on survey dates are not a suitable indicator of 
the duration of the transmission season. Last, ``person/months'' are 
unsuitable as a measure of transmission: an extension of season from 1 
to 4 months will have more impact than from 10 to 12 months. According 
to their model, an extension of transmission from 11 to 12 months 
results in 10 \6\ more person/months in a population of 10 \6\ people, 
whereas an extension from 1 to 5 months gives the same increase in a 
population of 250,000.
    What Tanser and colleagues have modelled is merely the duration of 
the transmission season, which they interpret as ``heightened 
transmission'' and increased incidence. A greater failing is their 
reliance on ``parasiteratio studies.'' The relations between 
transmission season and parasite prevalence, and parasite prevalence 
and clinical disease, are unclear but unlikely to be linear. Moreover, 
they use 1995 data for human populations, although these are projected 
to double by 2030. In addition, the proportion living in urban areas--
with a specific climate \10\ and orders of magnitude less malaria 
transmission \11\, \12\--is projected to rise from 37 
percent to 53 percent.\13\ For all these reasons, we do not accept the 
model as a ``baseline against which interventions can be planned.''
    It is regrettable that many involved in this debate ignore the rich 
heritage of literature on the subject. For example, in 1937, in his 
classic textbook,\14\ L W Hackett stated: ``Everything about malaria is 
so moulded and altered by local conditions that it becomes a thousand 
different diseases and epidemiological puzzles. Like chess, it is 
played with a few pieces, but is capable of an infinite variety of 
situations.'' A pressing question in Hackett's time was the changing 
distribution of the disease in Europe. On the role of climate, he 
wrote: ``Certainly, climate lays down the broad lines of malaria 
distribution . . . Nevertheless, although this is a very simple and 
plausible explanation . . . even the early malariologists (sic) felt 
that there was something unsatisfactory about it . . . malaria has not 
so much receded as it has contracted, oftentimes toward the north . . . 
Thus in Germany it is the northern coast which is still malarious, the 
south is free . . . There is, therefore, no climatic reason why 
(malaria) should have abandoned south Germany or the French Riviera.''
    We quote Hackett because we feel that the classic components of 
science--unbiased observation and systematic experimentation--cannot be 
sidestepped with models that omit many of his chess pieces. Yet Hales 
and Woodward \7\ begin by stating: ``The present geographical 
distribution of malaria is explained by a combination of environmental 
factors (especially climate) and social factors (such as disease-
control measures).'' In our opinion, ``even the early malariologists'' 
would surely disagree: much of the decline of malaria in Europe took 
place without control measures during a period when the climate was 
    The text by Hales and Woodward that follows displays a lack of 
knowledge. Thus, ``Most people at risk of malaria live in areas of 
stable transmission . . . '' is simply wrong. It is true that in many 
parts of the world malaria is termed ``stable'' because transmission 
remains relatively constant from year to year, the disease is endemic, 
the collective immunity is high, and epidemics are uncommon. However, 
in many other regions, the disease is endemic but ``unstable'' because 
annual transmission varies considerably, and the potential for 
epidemics is great. Climatic factors, particularly rainfall, are 
sometimes, but by no means always, relevant.\15\
    Again, ``On the fringes of endemic zones, where transmission is 
limited by rainfall . . . there are strong seasonal patterns, and 
occasional major epidemics'' is also wrong. In many regions, far from 
any ``fringes,'' malaria is endemic, stable, but highly seasonal. For 
example, in semi-arid regions of Mali, transmission is restricted to 
the rainy season, from July to September. The same 3 months constituted 
the transmission season for Plasmodium falciparum in Italy before it 
was eliminated.\16\ Paradoxically, in parts of the Sudan, rainfall is 
restricted to a month at most, but malaria is transmitted throughout 
the year. Female Anopheles gambiae survive severe drought and extreme 
heat by resting in dwellings and other sheltered places.\17\ Blood 
feeding and transmission continue, but the mosquitoes do not develop 
eggs until the rains return. This phenomenon, termed gonotrophic 
dissociation, is remarkably similar to the winter survival strategy of 
Anopheles atroparvus, the principal vector of malaria in Holland until 
the mid 20th century.\16\
    By contrast, malaria is unstable in many regions that normally have 
abundant rainfall, and epidemics occur during periods of drought. An 
illustrative example is the catastrophic 1934-1935 epidemic in Ceylon 
(now Sri Lanka), estimated to have killed 100,000 people.\18\ Worst hit 
was the southwestern quadrant of the country, where average annual 
rainfall is greater than 250 cm, and malaria was endemic, but unstable 
and relatively infrequent. The dominant vector, Anopheles culicifacies, 
breeds along the banks of rivers and tends to be scarce in normal 
years. In the years 1928-1933 there was abundant rainfall, river flow 
was high, An culicifacies was rare, and the human population was 
exceptionally malariafree. However, after failure of two successive 
monsoons, the drying rivers produced colossal numbers of An 
culicifacies, and the resulting epidemic was exacerbated by the low 
collective immunity. In the drier parts of the island, where An 
culicifacies was dominant but transmission was more stable, immunity 
protected the population from the worst ravages of the disease.
    Hales and Woodward state that ``the underlying problem'' of the 
future ``extension of seasonality'' of malaria is ``pollution of the 
atmosphere'', and call for rich countries to ``recognise their 
obligations to the poorest by substantially reducing fossil-fuel 
consumption.'' We understand public anxiety about climate change, but 
are concerned that many of these muchpublicised predictions are ill 
informed and misleading. We urge those involved to pay closer attention 
to the complexities of this challenging subject.

        Paul Reiter, Christopher J Thomas, Peter M Atkinson, Simon I 
        Hay, Sarah E Randolph, David J Rogers, G Dennis Shanks, Robert 
        W Snow, and Andrew J Spielman.

        PR is professor of medical entomology, Institut Pasteur, Paris, 
        France; CJT is senior lecturer in spatial ecology and Wolfson 
        Institute fellow in health and environment, School of 
        Biological and Biomedical Sciences, University of Durham, UK; 
        PA is professor of geography, University of Southampton, UK; 
        SIH is a Wellcome Trust research fellow, SER is professor of 
        parasite ecology, and DJR is professor of ecology, Department 
        of Zoology, University of Oxford, UK; GDS is at the U.S. Army 
        Centre for Health Promotion and Preventive Medicine, MD, USA; 
        RWS is professor of tropical public health, University of 
        Oxford; AJS is professor of tropical public health, immunology 
        and infectious diseases, Harvard School of Public Health, 
        Boston, MA, USA. SIH and RWS are also at the KEMRI Wellcome 
        Trust collaborative programme, Kenya.

    \1\ Reiter P. From Shakespeare to Defoe: malaria in England in the 
little ice age. Emerg Infect Dis 2000; 6: 1-11.
    \2\ Reiter P. Climate change and mosquito-borne disease. Environ 
Health Perspect 2001; 109 (suppl 1):141-61.
    \3\ Hay SI, Cox J, Rogers DJ, et al. Climate change and the 
resurgence of malaria in the East African highlands. Nature 2002; 415: 
    \4\ Shanks GD, Hay SI, Stern DI, Biomndo K, Snow RW. Meteorologic 
influences on Plasmodium falciparum malaria in the highland tea estates 
of Kericho, Western Kenya. Emerg Infect Dis 2002; 8: 1404-08.
    \5\ Rogers DJ, Randolph SE. The global spread of malaria in a 
future, warmer world. Science 2000; 289: 1763-66.
    \6\ Tanser FC, Sharp B, le Sueur D. Potential effect of climate 
change on malaria transmission in Africa. Lancet 2003; 362: 1792-98.
    \7\ Hales S, Woodward A. Climate change will increase demands on 
malaria control in Africa. Lancet 2003; 362: 1775.
    \8\ Thomas CJ, Davies G, Dunn CE. Mixed picture for changes in 
stable malaria distribution with future climate in Africa. Trends 
Parasitol 2004; 20: 216-20.
    \9\ Smith T, Charlwood JD, Kihonda J, et al. Absence of seasonal 
variation in malaria parasitaemia in an area of intense seasonal 
transmission. Acta Trop 1993; 54: 55-72.
    \10\ Arnfield A. Two decades of urban climate research: a review of 
turbulence, exchanges of energy and water, and the urban heat island. 
Int J Climatol. 2003; 23: 1-26.
    \11\ Snow R, Trape J, Marsh K. The past, present and future of 
childhood malaria mortality in Africa. Trends Parasitol 2001; 17: 593-
    \12\ Robert V, Macintyre K, Keating J, et al. Malaria transmission 
in urban sub-Saharan Africa. Am J Trop Med Hyg 2003; 68: 169-76.
    \13\ United Nations. World urbanization prospects: the 2001 
revision. Data tables and highlights. New York: United Nations, 2002.
    \14\ Hackett LW. Malaria in Europe, an ecological study. London: 
Oxford University Press, 1937.
    \15\ Gilles HM, Warrell DA, eds. Bruce-Chwatt's essential 
malariology. London: Edward Arnold, 1993.
    \16\ Bruce-Chwatt LJ, de Zulueta J. The rise and fall of malaria in 
Europe, a historico-epidemiological study. Oxford: Oxford University, 
    \17\ Omer SM, Cloudsley-Thompson JL. Survival of female Anopheles 
gambiae Giles through a 9-month dry season in Sudan. Bull World Health 
Organ 1970; 42: 319-30.
    \18\ Dunn C. Malaria in Ceylon: an enquiry into its causes. London: 
Bailliere, Tindall and Cox, 1937.
Other Attachments
    These articles are in committee files and can be found at their 
respective websites:

        Climate Change and Mosquito-Borne Disease, Paul Reiter, 
        Environmental Health Perspectives, Vol. 109, Supplement 1: 
        Reviews in Environmental Health, 2001 (Mar., 2001), pp. 141-


        From Shakespeare to Defoe: Malaria in England in the Little Ice 
        Age, Paul Reiter

        Emerging Infectious Diseases, Vol. 6, No. 1, January-February 


    Senator Vitter. Thank you very, very much, Doctor. I'll 
kick off the questioning.
    Dr. Corell----
    Dr. Corell. Yes.
    Senator Vitter.--I wonder if you could put up one of your 
first slides, which was the temperature chart, because I'm 
trying to understand it, in part, by----
    Dr. Corell. Sure.
    Senator Vitter.--comparing it to Dr. Armstrong's figure 1. 
Are you familiar with Dr. Armstrong's----
    Dr. Corell. I am not----
    Senator Vitter.--slide?
    Dr. Corell.--but I'd be happy to have a look at it. Yes, 
OK. I now know what----
    Senator Vitter. Right. Your----
    Dr. Corell. This----
    Senator Vitter.--chart basically goes back to----
    Dr. Corell. This is 2,000 years.
    Senator Vitter.--2,000 years. Dr. Armstrong's figure 1 is 
much more long term, I think.
    Dr. Corell. That's correct.
    Senator Vitter. It goes back 400,000 years.
    Dr. Corell. Right.
    Senator Vitter. And so, I guess the comparison--the 
conclusion from the comparison is--and correct me if I'm 
wrong--that the Earth has experienced similar temperature 
levels to the present day, but much further back than 2,000 
    Dr. Corell. That's correct. And I would say it's the 
CO2 that is way above the record, certainly in the 
record that's in his testimony, but there are several papers 
that suggest that we have not had these CO2 levels 
for 25 million years.
    Senator Vitter. Right. And his chart also suggests that, 
because if----
    Dr. Corell. Right.
    Senator Vitter.--you're looking at it----
    Dr. Corell. That's----
    Senator Vitter.--his chart of CO2 and 
CH4, they're----
    Dr. Corell. Are well----
    Senator Vitter.--way beyond----
    Dr. Corell.--well beyond the----
    Senator Vitter.--anything in the last 400,000 years. And 
    Dr. Corell. And----
    Senator Vitter.--provoked my question----
    Dr. Corell. Yes, about----
    Senator Vitter.--which is----
    Dr. Corell.--the lead-lag issue.
    Senator Vitter. Right.
    Dr. Corell. Let me say a word or two about it and go to 
another slide here, if I can, and that's this one. As this 
imbalance of heat comes into the system, and the ocean observe 
it--absorbs it, it's going to re-radiate that and heat--and 
reheat the atmosphere. But this out-of-balance is due to the 
CO2 level being much higher, creating the greenhouse 
effect. And so, there's--during a time when we have both 
natural variability and human-induced variability, or human-
induced warming, during that time the temperature is going to 
lag behind the rise in CO2. Do you follow that, from 
    Senator Vitter. Now, why is that different from a period 
where it's a purely natural process?
    Dr. Corell. Because--well, several reasons. One, there's a 
much slower rate of warming occurring in--during the natural 
process period. And, quite frankly, if you look at this 
400,000-year record, it's pretty hard to sort out the lead-lag 
relationship. In fact, some will argue that it--sometimes 
temperature leads the CO2 and other times it lags 
the CO2, and that's probably due to a bunch of--a 
whole group of natural processes. A lot of them are the 
wobbling and the precessions of the planet and so on. But what 
I want to make--the difference is that we are in a region now 
where we have clearly natural variability, and, on top of that, 
we have the human-induced increase in CO2, and that 
human-induced in CO2 is likely to cause the 
temperature to lag behind the CO2 rise.
    So, the answer to your question, in my judgment, is that we 
are going to see a continued rise in temperature. Most recent 
meeting in the U.K. held by John Shellnhuber and the group on 
the dangerous intervention issue, concluded that as we sit 
here, we're likely to see 2 to 3 degrees of warming, 
Centigrade, during this coming century. So, whether--we 
definitely will have a rise in temperature, given the rate at 
which CO2 is increasing today.
    Senator Vitter. Dr. Akasofu, do you have any reaction or 
    Dr. Akasofu. No, on this particular point, because as Dr. 
Corell mentioned, all the changes are going on. Climate change 
is going on, definite. No question about that. And the only 
thing we are trying to find is which portion is natural, which 
is manmade.
    Senator Vitter. Right.
    Dr. Akasofu. From our study, we--the--we cannot tell.
    Senator Vitter. Right.
    I want to go to Dr. Akasofu's figure 1, which is really 
interesting to me. His basic explanation of the dip in both 
Arctic and the smaller dip in global temperature between 1940 
and 1970 is that you have major natural factors, as well as 
manmade. What would be your explanation, Dr. Corell?
    Dr. Corell. Well, I think there are times when a--the--in 
this early part of the rise in temperature, where the natural 
variability can override. And we will see--I think the general 
consensus of the literature is that that relative cooling--
relative cooling that occurred in--as Dr. Akasofu has pointed 
out--has--was due to a natural variability factor. But now I 
think we can see from the record, certainly in the last half a 
century, that the IPCC and much of the literature will indicate 
that the predominant factor of the warming is coming from 
human-induced CO2 contributions to the atmosphere.
    Senator Vitter. How do they reach that conclusion? How do 
they parcel out natural versus human?
    Dr. Corell. Well, one way to do it--there are several--one 
is to take your models--and I would like to talk a little about 
the models, because you asked a very good question about that--
and ask yourself, How could we get the temperature that we have 
today? And we have a pretty good idea of solar variability over 
the last 50 to 100 years. We have a clear idea of what volcanic 
eruptions are. Those are--you know, those are cooling effects. 
In other words, we have a pretty good idea of the major 
contributing factors. If you try to get the temperature that we 
have today without the human-induced factor, you just can't get 
there. And there have been numerous papers that do this.
    Now, we're talking at the global scale. And I think----
    Senator Vitter. May I interrupt for a second?
    Dr. Corell. Yes.
    Senator Vitter. Why can't you get there, since, 
historically, Earth has been there?
    Dr. Corell. Well, the conditions of the past at which it 
got there were quite different than the ones we have today. I 
mean, there are times when we've had much warmer regions of the 
Arctic there. You know, we had mastodons running around in a 
much warmer--a much warmer set of conditions.
    What we're talking about here is, What's changing the 
conditions now, over the last, well, let's say 2 and a half 
million years, when we have had the glaciation periods with all 
these cycles occurring? During that time, we could not get to 
the temperatures we've gotten today--I mean, the CO2 
and temperatures we've got today--without having CO2 
being put into the atmosphere by humans.
    Senator Vitter. Well, again, doesn't Dr. Armstrong's figure 
1 suggest otherwise with regard to temperature, not 
    Dr. Corell. Well, he's not only talking about--Dr. 
Armstrong's--yes. Try me again. I was thinking of Dr. Akasofu's 
    Senator Vitter. No, no, that other figure----
    Dr. Corell. Oh, I----
    Senator Vitter.--the one----
    Dr. Corell.--I know which one you're talking--I just 
    Senator Vitter. Doesn't that----
    Dr. Corell.--your question.
    Senator Vitter.--suggest, contrary to what you just said, 
that you can't get there otherwise with regard to temperature, 
not--I mean CO2 levels, clearly----
    Dr. Corell. CO2, methane----
    Senator Vitter.--all-time high----
    Dr. Corell. Right.
    Senator Vitter.--nothing. But temperature level is not, at 
least yet.
    Dr. Corell. At this stage, we're at about the level--the 
maximum levels we've seen during the glacial period of the last 
million or 2 million years, that's correct. But what I'm 
suggesting is that we already know there's more temperature 
buried in the ocean to come out from CO2 already put 
in the atmosphere by humans during the past 10, 20, 30 years, 
so that the future----
    Senator Vitter. Well, but that is----
    Dr. Corell.--will be warm.
    Senator Vitter.--that conclusion assumes that CO2 
is driving--the single factor or predictor.
    Dr. Corell. Well, I think the physics on that is pretty 
clear, that CO2 and the greenhouse gases do trap the 
energy between the upper atmosphere and the ground, and warm 
the planet. I think that's--the physics on that's clear.
    I'm maybe not getting your point, sir.
    Senator Vitter. Well, again, it seems to me, in terms of 
the historical record, you're sort of assuming that CO2 
is the perfect predictor and overrides anything else.
    Dr. Corell. Well, I think if you do the physics on CO2 
and the other greenhouse gases, they will trap the energy 
between the upper atmosphere and the ground, and will warm the 
planet. And what is clear to us now is, the ocean has enough 
information--enough heat in it to warm the planet beyond 
anyplace we have been over the last, say, 400,000 years.
    Senator Vitter. Dr. Akasofu, obviously the Arctic is an 
extreme case compared----
    Dr. Akasofu. Yes.
    Senator Vitter.--to global situations.
    Dr. Akasofu. That's correct.
    Senator Vitter. Now, that could suggest that it's the 
perfect place to study, because it is--shows a heightened level 
of trends that are global, or it--maybe it could suggest the 
opposite, that it's sort of an anomaly. What's your conclusion 
about that basic question?
    Dr. Akasofu. It goes--the Antarctic, as you said, is an 
signal magnitude or amplitude is at least three times bigger. 
So, so much easier to study. And, furthermore, what really--in 
this latitude, you don't see .6 degree temperature change 
what's happening, but Arctic, you can see all kinds of----
    Senator Vitter. Right.
    Dr. Akasofu.--climatic--climate changes going on. So, the 
Arctic is, to me, the place we should study. That's--there is 
no disagreement with----
    Dr. Corell. No, no----
    Dr. Akasofu.--Dr. Bob Corell, yes. But the--Dr. Corell says 
yes, physics of the CO2 is greenhouse gas. Our 
question is, quantitatively, how many degrees, and where? And 
the observations show that the actual largest, most prominent 
warming taking--that was taking place in the continental 
Arctic. But somehow the IPCC computer could not produce that. 
And that means, to me, it's something else. And we found that 
it is something else, not the greenhouse effect. So, we have to 
be very careful here.
    Senator Vitter. I'm glad you mentioned that, because it 
goes back to some of the testimony from the first panel, where 
they suggested that some of the very recent work, including a 
publication in Nature very recently, fine-tuned some of the 
climatic models in such a way that it was very predictive, 
looking back to what we have measured historically. Can you 
react to that?
    Dr. Akasofu. Sorry, I don't think so at this time. I--our 
interest is try to understand the increase from 1920 to 1940--
    Senator Vitter. Right.
    Dr. Akasofu.--and then the decrease from 1940 to 1970. 
Unless we understand that, we don't think we understand the 
increase from 1970 on.
    Senator Vitter. Right.
    Dr. Akasofu. Yes.
    Senator Vitter. Let me ask it a different way. How good and 
perfected do you think the current climatic models are, in 
terms of temperature prediction, if you test it against that 
bit of history?
    Dr. Akasofu. I believe that there are all kinds of 
complexities there, but the general pattern, to me, that 
computers should be able to produce--I mean, we have advanced 
so much in our simulators, all kinds of a major supercomputers 
working, so I trust that, at least, you know, some aspects 
should be--you know, computer should reproduce. And if the 
computers cannot reproduce--and, you know, that was the basis 
for the Kyoto Protocol.
    Senator Vitter. Right.
    Dr. Akasofu. And if you say the computers are no good, then 
we have to abandon the Kyoto Protocol, too. So,----
    Senator Vitter. Right.
    Chairman Stevens?
    The Chairman. Thank you.
    Dr. Akasofu, at your request we authorized funding for 
further temperature measurements in the Arctic Ocean over the--
what, the last 3 years? How many years?
    Dr. Akasofu. Yes.
    The Chairman. And there--have you had any tentative 
conclusions from those temperatures as to whether there is 
noticeable change now, as far as the temperature of the Arctic 
    Dr. Akasofu. Yes. The--what's happening is that the warm 
North Atlantic water is intruding into the Arctic Ocean, and we 
are tracing this water. It's moving around Siberian coast, and 
then moving toward Alaska. So, although it's a very complicated 
thing, but suddenly tremendous heat is coming from the North 
Atlantic into the Arctic Ocean, which is, I'm sure, the partial 
reason for the ice melting there.
    The Chairman. And is that in any way related to the recent 
intensity of the sun's heat, as far as the Atlantic Ocean is 
    Dr. Akasofu. That, I can't tell. We just learned that--in 
the last paper, that as much as 30 to 40 percent of temperature 
increase could have been due to just the solar output increase. 
But we have to now go back and look at the computer modeling 
and put it in that and see if that will warm up North Atlantic 
or not. We have not done that yet.
    The Chairman. And this--we have your statement, and figure 
6 showing the distribution of that Atlantic water, the so-
called Atlantic oscillation. How long has that been going on, 
do you know?
    Dr. Akasofu. Oh, as far as we determine, you know, it's at 
least 50--accurately, the last 50-60 years over good data--what 
we call NAO, North Atlantic oscillation, intensity changes, and 
we know that.
    The Chairman. Well, is that warming of the Arctic Ocean 
related to some of the change we see in our State now, as far 
as the permafrost and basic change in the climate?
    Dr. Akasofu. OK, that's--our scientists have--different 
scientists have a different point of view. The continental 
portion of warming, they think that could be something else. 
But the--they are not sure yet.
    The Chairman. By that, you mean what's happening in the 
Arctic Ocean could be both natural and manmade.
    Dr. Akasofu. I think so.
    The Chairman. How long a period do we have to study that to 
reach a--any tentative conclusion on it?
    Dr. Akasofu. The--in the past--I think--this is my view--
that people are aware that the--there are natural and manmade, 
both components, but not many people really spent the time to 
separate those out. It's very difficult. Whenever there is--we 
should make the effort. And we are now concentrating--some of 
us really working hard to do that particular job, rather than 
study with just the North Atlantic water coming in or something 
    The Chairman. Have you flown over the Arctic area recently?
    Dr. Akasofu. Not recently, not last year or so.
    The Chairman. I took one flight--this'll be my last 
comment--over--coming from the West Coast, going over to 
Barrow, and it was pointed out to me the places where the ocean 
had been up far inland from where it is now. And the pilot 
indicated that it showed that while we think the water is 
rising now, it hasn't come up near where it was in years--many 
years gone by.
    Dr. Akasofu. Yes.
    The Chairman. Now, are you able to study those other areas 
and see what the fluctuation has been, in terms of the Arctic 
Ocean's intrusion upon the Alaska part of our continent?
    Dr. Akasofu. Some of us are studying the ocean conditions 
or land--the features from the last Ice Age, not before that. 
But I think our people are collecting lots of data from during 
the last age, can see the major changes. And also even during a 
little ice age we had from 1300 to 1800, some major changes in 
terms of glaciers advance and retreat.
    The Chairman. I don't know if my colleagues had a chance to 
read the statement you've got--that you've submitted, but very 
clearly I take it that the impact that you're trying to leave 
with us, is, we don't know enough yet to make a judgment as to 
what part of this is manmade and what part is natural.
    Dr. Akasofu. I think I agree with Dr. Armstrong. We are 
trying, trying. This is very hard. And perhaps IPY, 
International Polar Year, when some scientists concentrate on 
this, we may make good progress.
    The Chairman. Thank you very much.
    Senator Vitter. Thank you.
    Senator Lautenberg?
    The Chairman. I want to thank the others, too, also, but I 
have to go to a meeting. I don't want to prolong this right 
    Senator Lautenberg. Mr. Chairman, I'm a little confused 
here with something--some of the things that are said. And I 
ask Dr. Akasofu, Are you aware of any peer-reviewed science 
study that's said--or asserted that the present warming in the 
Arctic or globally is entirely due to human-caused global 
    Dr. Akasofu. It's--I believe that is more of the press 
takes that view, but most scientists agree that there are two 
components, those manmade----
    Senator Lautenberg. I understand that, sir. I just want to 
be sure, because as I read your paper I had the--I drew the 
understanding that you ascribe most of this to human-caused 
global warming, and that the natural phenomena, the natural 
changes that are caused, are not something to be as concerned 
about. And now you do say there's a division, that there--it--
the--both areas result in these changes that we're seeing. The 
changes are obvious. You've confirmed that in your----
    Dr. Akasofu. Yes.
    Senator Lautenberg.--statement.
    Dr. Akasofu. Right. No question.
    Senator Lautenberg. Yes.
    Dr. Akasofu. Yes. Dr. Corell described it beautifully, 
those changes.
    Senator Lautenberg. Yes.
    Dr. Akasofu. The question is, How much is due to----
    Senator Lautenberg. Yes. How much, Dr. Akasofu, would you--
do you think that we ought to get after those things that we 
identify as caused by human existence, CO2? Is that 
largely caused by human activities, or is that--is there any of 
that, that comes from natural----
    Dr. Akasofu. OK. In science--in scientific methodologies, 
we assume, say, it is due to carbon dioxide, and then the--we 
use a supercomputer--supercomputer behave like virtual Earth. 
We put in CO2 into, and then calculate the result.
    Senator Lautenberg. Yes.
    Dr. Akasofu. And if the results agree with the 
observations, then that is the way to confirm that----
    Senator Lautenberg. Yes, I----
    Dr. Akasofu.--it's CO2.
    Senator Lautenberg. Forgive me for----
    Dr. Akasofu. There is, so far----
    Senator Lautenberg.--interrupting, but----
    Dr. Akasofu. There is, so far, no confirmation yet.
    Senator Lautenberg. Well, but--so, should we not intervene 
in trying to reduce the human contribution to----
    Dr. Akasofu. No, I am not saying that at all.
    Senator Lautenberg. No, I know you're not saying that, 
but--I'd like you to say that. But the thing is that--at what 
point do you say--``you,'' I'm saying, generic ``you,'' lots of 
people--say, ``Hey, we know that this is a phenomena that 
portends bad things for the human race.'' And if we agree with 
that, then I say, ``Well, what--at what point do we ask the 
politicians''--Dr. Reiter said something about political hay 
being made of this, as opposed to science. I'm going to ask you 
about that. And so, at what point, Dr. Corell, does the alarm 
sound loudly enough that says, ``Hey, let's stop destroying our 
forests, let's stop emitting these carbon dioxide chemicals--or 
results into the air''? At what point do we take care to join 
in the protection of our environment and our lives?
    Dr. Akasofu. There is no question that we have to--I don't 
think we can ever reduce the total amount of carbon dioxide in 
the air, but we should try to reduce the rate of increase. 
China is----
    Senator Lautenberg. Dr.----
    Dr. Akasofu.--coming, India is coming----
    Senator Lautenberg. Thank you.
    Dr. Akasofu. Yes.
    Senator Lautenberg. Dr. Corell?
    Dr. Corell. Yes, I think it's pretty clear from the 
assessments that the scientific community have put together, a 
variety of them, whether it be IPC, national assessment of the 
U.S. or Canada or other countries around the world, our recent 
Arctic assessment clearly indicates that it's time for action. 
And let me tell you why I believe so strongly it is time for 
    If we were wise enough to take our CO2 and 
reduce it, like, over the next 100-150 years, OK--this is the 
result of some model studies--it would take the planet about 
200 years for the CO2 to stabilize at some higher 
level, 700 or so, something--some number, quite a bit higher 
than we are today. It'll take another 200 years, roughly, for 
the temperature to stabilize. So, we're talking about 3- to 500 
years before the planet's stabilized. This is if we act, and it 
takes us 100 to 150 years to bring things down.
    The real sleeper is that sea-level rise will continue for 
probably 1,000 or more years, with those increased temperatures 
that are a result of the higher levels of greenhouse gases. So, 
if that's so--and we believe strongly, it is; this is IPCC 
results that came out of our study, as well--it seems logical 
that you ought to move that action time shorter to lower those 
temperature rates and to reduce the time for the stabilization 
to occur.
    So, I think the conventional wisdom within the scientific 
community is that we know enough now to take appropriate 
action. That's a political issue. That's an issue for you and 
others like you, to figure out how you take those steps, but 
we're trying to suggest to you, it is timely, and it is now 
that such steps should----
    Senator Lautenberg. Sure.
    Dr. Corell.--be taken.
    Senator Lautenberg. Yes, a recommendation is being clearly 
made from the abundance--from the gathering of science--
scientific knowledge that we have now, that we ought to get on 
with changing the pattern of what we see overtaking us, by 
intervening in the emission of CO2--and, again, I 
use deforestation as the example, but lots of things that we do 
as humans that violate the chances for our environment to 
succeed, as we know it.
    Dr. Corell. Agreed.
    Senator Lautenberg. Dr. Reiter--unfortunately, we're going 
to have to rush through this--you use the equivalent of the 
canary and the coal mine, in terms of malaria. And you know 
what that example, traditional----
    Dr. Reiter. Oh, they were British mines, I think.
    Senator Lautenberg. Yes. So, you say that, and you don't 
like the environmental activists using big talk of science to 
create simple, but false, paradigms. We have every right--and 
I'm not talking as a United States Senator, and I'm talking 
about every right as a human being--to take what we hear and 
take what we read and take the evidence that we see in front of 
us, all kinds of indications that this world is a less 
accommodating place than it was. And you--your closing comment, 
I think, is one of the, kind of, more interesting, worrying 
about the weather, ``Ah, don't worry about that.'' You're 
right, why worry about a Katrina or a tsunami or frequency of 
these storms and the ferocity of these storms, when malaria is 
not shown to be anything that's produced that's essentially or 
totally a tropical disease or--it doesn't indicate any real 
growth over the years, with substantial reductions, but a 
little spike. And you're a scientist, and a very well educated 
one, but I think worrying about the weather, other than to--
buying an umbrella or something like that, is probably a good 
idea. And so--and it's consistent with what we want to do here; 
and that is, gather information that helps us spur some 
activity. That's what we do. We're--we have the political 
muscle to do things, unless it's counteracted by structure of 
    You know, I think that, you know, we have a suggestion now 
that as--that gas prices are so high that we ought to break 
environmental rules that exist now and get on with it, getting 
that gasoline price down. As they say in my old schoolyard--I 
grew up in a tough area--``It ain't gonna happen that way,'' I 
can tell you. We can violate good environmental activities, and 
it's not going to affect what we--what happens in gas prices. 
We're--there's a whole other thing there.
    And what we do here, as legislators, is react to things. We 
rarely ever do anything that's creative in major magnitude 
that's induced by other than a reaction to a--what happens. And 
I was listening to these discussions about the hundreds of 
years away, and--but we have an obligation to worry about those 
hundreds of years away.
    And when I see a report put out for the Navy that says, 
``The Navy's got to be prepared in the second half of this 
century to fight off refugees seeking higher land,'' we know 
now people will get into tire tubes and chance trips with 
shark-filled waters to get to this great country of ours. But 
if people are going to be deluged by water--and we're talking 
about places that are not so distant from us, not necessarily 
Bangladesh, which is a--threatened, but the Netherlands and 
places like that.
    And, Mr. Chairman, you've experienced the worst of what 
happened in the--when a storm hits and the water rises above 
your capacity to contain it. So, we ought to get on with our 
task. And I would hope that the scientists would scare us a 
little bit and not let--let us feel too comfortable about, 
``Well, natural causes.'' If there is a natural cause, there's 
a natural cause, but if there isn't, then we ought to do 
something about that share of it.
    Dr. Reiter. May I answer your question?
    Senator Lautenberg. Sure.
    Dr. Reiter. First of all, I didn't mean to be flippant 
about the importance of the weather. What--and, again, I chose 
my own field as an illustration of problems of public health.
    I'm very glad that you say that I'm well educated. I like 
to think I could be better educated.
    What I would urge you to do--and I would urge all of those 
who are interested, at least in the health aspects of this 
debate--is to look up the credentials, the scientific 
credentials of the principal exponents--proponents, I'm sorry--
proponents of this disastrous situation, and compare them to 
the credentials, scientific credentials, of those who are 
essentially saying, ``Well, wait a moment. What are you saying? 
We don't have--we don't have the evidence for this.'' And if 
you look--I mentioned the IPCC, and I know that others have 
talked about the IPCC in a different way. I can only talk in 
the field of health. I can tell you, please look at----
    Senator Lautenberg. So, you're critical of the IPCC.
    Dr. Reiter. Yes. Well, hang on. May I finish? If you look 
at the credentials of the lead authors----
    Senator Lautenberg. Dr. Reiter, I must leave. And I don't 
want to leave an empty chair and be disrespectful. So, I would 
say this, that when the National Academy of Sciences 
contributes their view, that there is pretty solid evidence 
there, and other distinguished science groups. I say, ``Well, 
OK, you might be wrong.''
    Forgive me, I've got to go.
    Senator Vitter. Dr. Reiter, please finish up. I'm all ears.
    Dr. Reiter. Well--no, I don't want to continue about the 
IPCC--that's a quite different issue--except to suggest that 
you look at the credentials of the lead authors. You will find 
that none of them--neither of them have any credentials in the 
field of public health. And if you look back to the reports of 
2001 and 1995, you will see exactly the same. You will find 
that there are people there whose previous studies were on 
motorcycle crash helmets and the effects of cellular telephones 
on brain cancer. These are issues that really may be important, 
but, when we are talking about public--important public-health 
issues, we need to go to the people who specialize in public 
    Senator Vitter. Actually, I was going to ask you about the 
IPCC, because I find it very interesting that both you and Dr. 
Corell refer to it, in, of course, completely different ways. 
I'd just ask you to follow up on your comments and your 
testimony. The IPCC exercise, how driven do you think it is by 
scientific rigor or politics and ideology?
    Dr. Reiter. First of all, again, I can only speak for the 
health chapter, Chapter 8. In my opinion, we have to remember 
that this is the Intergovernmental Panel on Climate Change. 
Those--you may notice that I added to my dossier for you a 
paper--an article that nine of us, who consider ourselves 
leading experts in our field, published in The Lancet. We 
called it, ``A Call for Accuracy: Malaria and Climate Change.'' 
And, basically, none of us are on the panel--are on the Chapter 
8 Panel. I can also tell you that I know of certain very highly 
respected persons that were nominated by the U.S. Government 
for lead authorship in Chapter 8 and were turned down in favor 
of people--one person who has not a single scientific article 
written in the whole career.
    So, I think, at least in my field, yes, there is a strongly 
biased selection of people, and I know, also, from people who 
have been expert reviewers, that the expert--the review system 
is very interesting. Normally in science, review is by 
anonymous peer review. And the--in the IPCC, it is the 
opposite. It is by nonanonymous peer review. The expert 
reviewers discuss with the authors and come to so-called 
consensus. Now, when we did the U.S. Government evaluation in--
about 5 years ago, it was the opposite, or, rather, those of 
us--well, let me go on to what the real opposite was. The 
discussions were public domain. You can actually find out what 
those discussions were by looking on the Web. You cannot see 
what the criticisms were of the authorship in the first and the 
second draft of the health chapter. In other words, what I feel 
is that a major investigation of the means by which the 
conclusions of the IPCC, at least in my field, are drawn, is 
    Senator Vitter. Is it fair to say, then, that some of the 
traditional methods brought to scientific publication, like 
anonymous peer review, are abandoned in that U.N. process?
    Dr. Reiter. Well, it certainly isn't anonymous peer review. 
And it is very hard for those of us who are in this field--as I 
mentioned before, it is very hard for us to make some sort of 
scientific comment without either being ignored or being called 
``skeptics,'' in a rather derogatory way.
    What I tried to say, policymakers like yourself 
increasingly depend on science for making policy. And, by the 
way, scientists depend a great deal on policymakers for their 
living. But in a democratic society, policymakers respond to 
the public conceptions of these issues. We scientists are not 
really very good at essentially communicating with the public; 
or, rather, I think the public doesn't quite realize the way--
the difficulty there is in conveying the way that science 
    Public conceptions are essentially shaped by the press. We 
scientists also find it very difficult to deal in a scientific 
way with the press. The press normally picks up on those 
things, as is obvious, that have, perhaps, the most extreme 
implications on life on Earth.
    On the other hand, those people who would like to speak on 
behalf of scientists, whether they are scientists or not, have 
a very much greater influence on the press, on public 
conceptions, and, therefore, on policymaking. And this, I feel, 
is not only in this field of climate change, but it also 
applies to many other issues that have become controversial or 
have become important in the way that policy is made.
    Senator Vitter. Thank you very much.
    Thanks to all of you. This has been quite significant and 
lengthy and wide-ranging hearing. I appreciate all of your 
testimony and participation. Again, several of you came from 
quite a distance, we deeply appreciate that.
    And, with that, the Subcommittee hearing is adjourned.
    [Whereupon, at 5 p.m., the hearing was adjourned.]
                            A P P E N D I X

 Prepared Statement of Hon. Daniel K. Inouye, U.S. Senator from Hawaii
    In just the last few months a number of alarming new studies have 
come out on the projected and observed effects of climate change. These 
studies--and the testimony today--report that some projected climate 
change impacts are already occurring, and these changes are taking 
place at a faster pace than predicted.
    Latest estimates foresee a warming of the Earth's temperature of 
somewhere around five degrees by the end of the century. By 2100, sea 
levels could be several feet higher than they are now, which would have 
devastating effects on coastal areas, including my home State of Hawaii 
and the other Pacific Island nations. We have already seen the powerful 
destruction tsunami or severe weather can have on our low lying 
islands, and this damage will be magnified under the National Oceanic 
and Atmospheric Administration's (NOAA) projections of a one to three 
foot rise in sea level.
    Scientists also tell us that if trends continue as projected, we 
will see an increase in the already alarming growth in ocean 
acidification and coral bleaching events. These ocean changes would 
have virtually irreversible impacts on the fisheries and tourism 
industries and thus the Hawaiian economy. NOAA tells us that it took 
80,000 years for ecosystems to recover from the last mass extinction 
from ocean acidification.
    As I have noted previously, I also have serious concerns about the 
Administration's efforts to suppress or downplay the findings of 
government scientists, particularly in this area of global climate 
research. It is only through broad dissemination of their research and 
public conversation that we can effectively tackle the causes of 
climate change. We must have the benefit of a full and open scientific 
assessment of the likely effects of climate change in the next 20 to 50 
years, as already required by law. The Administration should not be 
avoiding and suppressing our scientists and their message, but rather 
listening to them attentively, and making plans to prevent dangerous 
interference with the climate system.
    I am very interested to hear more today about how climate change is 
going to affect all of us, what the Administration and others think we 
can do to prevent the worst impacts, and what we must do to prepare for 
the impacts that are already unavoidable.
  Response to Written Questions Submitted by Hon. Daniel K. Inouye to 
                       Steven A. Murawski, Ph.D.
    Question 1. There is a general scientific agreement that sea level 
rise is occurring at a global average rate of two millimeters per year. 
Sea level rise is projected to accelerate during the 21st century, with 
the most significant impacts in low-lying regions where subsidence and 
erosion problems exist. Rising sea level has worldwide consequences 
because of its potential to alter ecosystems and habitat in coastal 
regions. Sea level rise and global climate change issues in the coastal 
zone include:

   Higher and more frequent flooding of wetlands and adjacent 

   Increased flooding due to more intense storm surge from 
        severe coastal storms;

   Increased wave energy in the nearshore area;

   Upward and land-ward migration of beaches:

   Accelerated coastal retreat and erosion;

   Saltwater intrusion into coastal--freshwater aquifers;

   Damage to coastal infrastructure; and

   Broad impacts on the coastal economy.

    Dr. Murawski, in your testimony you discuss the effects of sea 
level rise on islands and several atolls in the Northwestern Hawaiian 
Islands. I am more interested in hearing about the potential impacts of 
sea level rise on the inhabited islands of the Pacific region.
    Can you tell us about the potential for adverse impacts from sea 
level rise on the population centers of the Central and Western 
Pacific, particularly with respect to port and road infrastructure, 
coastal habitats, living marine resources, and vulnerability of towns 
and villages to extreme coastal events, like tsunamis and typhoons?
    Answer. NOAA monitors sea level and uses the data to compute 
trends. The following table provides estimates of relative mean sea 
level trends based on analysis of tide gauge observations. The trends 
included in this table are ``relative'' measurements because they 
include both the effects of global sea level change and the local 
vertical land movement. The accepted range of global sea level rise by 
the scientific community is between 2.0 and 3.0 mm/yr.

       Station                      Trend               Standard Error *
Johnston Atoll         0.68 mm/yr (0.22 ft/century)    0.31 mm/yr
Midway Islands         0.09 mm/yr (0.03 ft/century)    0.31 mm/yr
Guam                   0.10 mm/yr (0.03 ft/century)    0.09 mm/yr
Pago Pago              1.48 mm/yr (0.49 ft/century)    0.56 mm/yr
Kwajalein              1.05 mm/yr (0.34 ft/century)    0.51 mm/yr
Chuuk Atoll            0.68 mm/yr (0.22 ft/century)    0.09 mm/yr
Wake Island            1.89 mm/yr (0.62 ft/century)    0.35 mm/yr
Honolulu               1.50 mm/yr (0.49 ft/century)    0.14 mm/yr
Hilo                   3.36 mm/yr (1.10 ft/century)    0.21 mm/yr
Mera, Japan            3.66 mm/yr (1.20 ft/century)    0.12 mm/yr
Aburastubo. Japan      3.33 mm/yr (1.09 ft/century)    0.14 mm/yr
Tonoura. Japan         0.38 mm/yr (0.12 ft/century)    0.12 mm/yr
Wajima, Japan          -0.80 mm/yr (-0.26 ft/century)  0.13 mm/yr
Xiaman, China          1.02 mm/yr (0.33 ft/century)    0.30 mm/yr
* The standard errors provide a measure of uncertainty in the computed

    Even with the low rates of relative sea level rise tabulated above, 
any increase or acceleration in the trends due to climate variability 
and change could have significant long-term effects on the remote ocean 
islands. This is because portions of many of the islands are low-lying 
with relatively flat topographies. Analysis of the tide gauge records 
from these islands show no apparent acceleration in the relative sea 
level trends to date.
    NOAA is working with local coastal managers and stakeholders in the 
Pacific, through the Pacific Services Center, to improve the 
development and delivery of risk management-related information 
products and services in the Pacific. The project is called Pacific 
Risk Management `Ohana (family) (PRiMO).
    On a larger scale, NOAA is working with other Federal agencies on 
the Climate Change Science Program, which is directing a range of 
research to address coastal sensitivity to climate change.
    URL References:



    Question 2. As you know, we had tragic loss of life in Hawaii due 
to a dam failure after a period of torrential rains. Does the National 
Oceanic and Atmospheric Administration's (NOAA) research suggest we 
will need to pay more attention to mudslides and infrastructure failure 
as the oceans warm and rise?
    Answer. One need only look at Central America's experience with 
Hurricane Mitch in 1998, and California during the 1997-1998 El Nino 
event, to see the potential devastation that intense precipitation can 
bring to a vulnerable region and its infrastructure. More recently, 
loss of life and property due to heavy rains were reported in Hawaii 
(February to March 2006) and the northeastern United States (May 2006), 
and the early onset of the summer monsoon in India killed 38 people 
(June 2006). NOAA research indicates that warmer climates will bring 
higher probabilities of extreme precipitation, even in locations where 
average precipitation may be decreasing. \1\ NOAA data show increases 
in water vapor as the global climate has warmed, consistent with 
theoretical expectations. Thus, as the oceans warm and sea level rises 
the compounding effects of heavy rainfall and storm surge will need to 
be assessed to understand their full impact on coastal infrastructure.
    \1\ Karl, T. R., and K. E. Trenberth, 2003. Modern Global Climate 
Change. Science, 302: 1719-1723.

    Question 3. What is the range of marine ecosystem impacts that we 
might expect to see in the Western Pacific, and over what timeframes?
    Answer. Sea level rise is compounded by subsidence on islands such 
as Maui and Hawaii, which have rates of relative sea level rise of 3.5 
to 5 mm/yr. Impacts to marine environments in the Western Pacific could 
include changes in water circulation, wave dynamics, sediment 
production and resuspension, transport of pollutants and nutrients, and 
possibly larval transport. Ecosystem-based management strategies can 
help mitigate the effects on reef environments.
    Changes to reef processes and reef distribution may occur in areas 
most vulnerable to changes in sea level. According to the U.S. 
Geological Survey, which has undertaken a study to understand and 
predict the response of reefs to accelerated sea-level rise, projected 
sea level rise will be particularly significant for low-lying coral 
atolls, many of which have maximum elevations of less than 5m above 
present sea level. Even in high island settings (e.g., main Hawaiian 
islands and Guam), large volumes of sediment stored at or near sea 
level could be exhumed and transported to reefs by increases in sea 
    Coral ecosystems in the Western Pacific are also susceptible to 
other ramifications of climate variability and change, including coral 
bleaching caused by elevated sea surface temperatures and ocean 
acidification caused by increased carbon dioxide concentrations. There 
is not a strong consensus on the potential effects of climate 
variability and change on other coastal and marine island ecosystems. 
such as mangrove and seagrass ecosystems of the Western Pacific.
Accelerating Ocean Acidification
    Question 4. A National Oceanic and Atmospheric Administration 
(NOAA) study released in April 2006 shows that rising temperatures are 
increasing the daily uptake of carbon dioxide by oceans. This changes 
the chemistry of seawater, making it more acidic, and having negative 
effects on corals and other marine life. NOAA oceanographers confirmed 
studies conducted in the 1990s showing that ocean acidification is 
occurring at ``significantly increased rates,'' and say ocean chemistry 
is changing at least 100 times more rapidly than it has during the 
650,000 years preceding our industrial era. At current levels of carbon 
dioxide emissions, NOAA computer models predict that oceans will 
continue to acidify to ``an extent and at rates that have not occurred 
for tens of millions of years.''
    Dr. Murawski, the National Oceanic and Atmospheric Administration's 
(NOAA) recent study shows that ocean acidification is occurring at 
``significantly increased rates,'' adversely affecting water chemistry 
and leading to ``major negative impacts'' on corals and other marine 
    The National Oceanic and Atmospheric Administration (NOAA) has 
stated that ocean acidification could substantially alter the 
biodiversity and productivity of the oceans. Can you tell us when we 
might see the effects of ocean acidification on the biodiversity and 
productivity of the ocean in the Pacific islands region?
    Answer. While many of the models applied to describe the projected 
trends in ocean acidification have centered on the Pacific Ocean, the 
models are not specific to the Pacific islands region and uncertainty 
remains regarding the precise timing and biological impacts. Recent 
estimates indicate roughly half of the anthropogenic CO2 
released since the industrial revolution has been absorbed by the 
surface waters of the world's oceans. \2\ This has resulted in probably 
the most dramatic decrease in ocean pH for the past 400,000 years. \3\ 
This process of ocean acidification imparts an important control on the 
degree to which the surface waters are supersaturated with respect to 
carbonate minerals (i.e., saturation state), from which some marine 
organisms construct their skeletal structures. Studies on hermatypic 
corals, coralline algae, mesocosm coral reef communities and natural 
coral reef ecosystems have shown that the calcification of a diverse 
selection of organisms and natural systems correlate strongly with 
aragonite saturation state.
    \2\ Sabine. CI., R.A. Feely, N. Gruber. R.M. Key, K. Lee, J.L. 
Bullister, R. Wanninkhof, C.S. Wong, D.W.R. Wallace, B. Tilbrook. F.J. 
Millero, T.-H. Peng, A. Kozyr. T. Ono. and A. F. Rios 2004. The oceanic 
sink for anthropogenic CO2. Science. 305, 367-371.
    \3\ Orr J.C., Fabry V.J. Aumont 0., Bopp L. Doney S. C., Feely R.A. 
Gnanadesikan A. Gruber N., Ishida A. Joos F., Key R. M., Lindsay K., 
Maier-Reimer E. Matear R., Monfray P., Mouchet A. Najjar R. G. Plattner 
G.-K,. Rodgers K.B. Sabine C.L. Sarmiento J.L. Schlitzer R., Slater 
R.D., Totterdell I.J., Weirig M.-F., Yamanaka Y., and Yool A. 2005. 
Anthropogenic ocean acidification over the twenty-first century and its 
impact on calcifying organisms. Nature. 437(7059), 681.
    The aragonite (calcium carbonate) saturation state has already 
declined from pre-industrial levels by more than 10 percent in the 
tropics and could drop a further 20-30 percent by 2100 if CO2 
emissions continue as projected by the Intergovernmental Panel on 
Climate Change (IPCC)1S92a ``Business as Usual'' scenario (1995). Model 
results based on the more conservative IPCC SRES B2 emissions 
atmospheric CO2 increase scenario, together with laboratory 
estimates of the sensitivity of corals to ocean acidification, suggest 
that the waters of the Pacific islands region will may not support 
optimal coral calcification rates beyond approximately 2050 
20 years. \4\
    \4\ Guinotte J. M., Buddemeier R. W., and Kleypas J. A. 2003. 
Future coral reef habitat marginality: temporal and spatial effects of 
climate change in the Pacific basin. Coral Reefs, 22(4). 551.
    These scenarios are projections of what is likely to occur with 
regards to the broad oceanic changes in saturation state. However, the 
projections are less likely to accurately predict coastal zone 
conditions, where complexities can arise involving buffering by 
dissolution of carbonate minerals. Furthermore, the models assume an 
equitable biologic response to changes in saturation state while it is 
well demonstrated that the magnitude of the effects is not universal 
and varies between species and even among individual organisms within 
the same species.
    We are only beginning to understand how rapid changes in ocean 
chemistry will impact marine biota. The magnitude of the effects is not 
universal and varies between species and even among individual 
organisms within the same species. It is not yet fully understood how 
such changes in calcification rate will impact marine ecosystems at the 
community scale. For example, it has been suggested that although the 
calcification rates of corals are expected to decrease in response to 
ocean acidification, organisms such as seagrasses and algae could 
benefit from the increased CO2 and thereby hasten the 
community shift to a lower biodiversity environment. In addition to 
impacts resulting from ocean acidification, marine ecosystems will also 
respond to other climate-and human-induced stresses (e.g., increasing 
sea surface temperature, rising sea level, overfishing. etc.).
    Studies have begun to investigate the synergistic effects of 
decreased saturation state and increased temperature on selected coral 
species. It is difficult to determine the combined effect these 
stressors will have, and the precise timing of any impacts. As a 
consequence of our current uncertainty with regards to the anticipated 
coastal changes in saturation state, the variability in the biological 
response to such changes, and the complexities of other climate change 
variables, we cannot be certain of the exact rates, final extent, and 
detailed geographic distributions of the impacts of ocean 
acidification. The current prevailing scientific view is that such 
changes will largely be detrimental to coral communities and that such 
changes will likely be experienced within this century.

    Question 5. What will be the effects of ocean acidification on the 
corals and associated fisheries and tourism businesses that the Pacific 
islands are so dependent upon?
    Answer. The full range and magnitude of the biological and 
biogeochemical effects of ocean acidification are still so uncertain 
that a reliable and quantitative estimate of the likely socioeconomic 
effects is not yet possible.

    Question 6. What future programs or products are planned by NOAA to 
monitor the oceans' response to growing carbon dioxide levels and 
provide decision-makers with advice on mitigation options, particularly 
in the Pacific?
    Answer. Ocean acidification is an emerging issue: hence current 
understanding does not offer many specific mitigation options at this 
time. Efforts have begun to develop observatories at select U.S. coral 
reefs that monitor a Reef Metabolic Index (RMI) designed to track broad 
changes in community-scale calcification. These observatories will 
expand on existing monitoring stations, remote sensing efforts, and 
near-reef carbon measurements to measure overall biological performance 
of the ecosystem. In addition, efforts have begun using satellite 
remote sensing to document the coastal and global long-term 
distribution of the phytoplankton Emiliania huxleyi, which is a key 
algal species demonstrated to exhibit sensitivity to changes in ocean 
pH. This kind of information will be essential for decision-makers to 
develop an understanding of the magnitude and extent of the changes 
that are occurring within U.S. coral reef ecosystems over time, and for 
developing and testing the effectiveness of newly developed mitigation 
Response to Written Questions Submitted by Hon. Frank R. Lautenberg to 
                       Steven A. Murawski, Ph.D.
    Question 1. In your written testimony you indicate that scientific 
uncertainties remain on how much of the observed warming is due to 
human activities. Given the complexity of global climate change, that 
past observations of the climate are uncertain, and that projections 
are being asked looking a century or more into the future, is it 
inevitable that there will be uncertainties, no matter how much 
research is done?
    Answer. The short answer is that yes, there will be uncertainties 
no matter how much research is done because the climate system is not a 
completely deterministic system. Uncertainty associated with climate 
variability and change can have many sources, including the nature and 
quality of the available data: the ability of models to capture 
processes and their relationships (including predictability); and other 
factors related to the impacts of human behaviors \1\ (Moss and 
Schneider, 2000). There is also uncertainty about the natural 
interactions among the various components of the climate system. Given 
the impact uncertainty has on our efforts to understand, communicate, 
and adapt to climate change, the scientific community continues to 
pursue this area of research and has taken steps in recent years to 
address the nature of uncertainty in their assessment efforts, as 
reflected in the U.S. Climate Change Science Program (CCSP) and the 
Intergovernmental Panel on Climate Change (IPCC) reports.
    \1\ Moss. R., and S. Schneider, 2000. Uncertainties, in Guidance 
Papers on the Cross Cutting Issues of the Third Assessment Report of 
the IPCC, edited by R. Pachauri, T. Taniguchi, and K. Tanaka, 
Intergovernmental Panel on Climate Change (IPCC), Geneva.
    For example, the CCSP Synthesis and Assessment Product 5.2 is 
intended to further develop this topic through the synthesis, 
assessment, and communication of what is known about the character and 
magnitude of uncertainty, as it applies to climate, and to address some 
potential approaches to decision-making given the uncertainty. This 
report will address uncertainty related to decision support activities, 
ranging from the conduct and communication of research to the actual 
consideration and use of scientific knowledge and information products 
in decision-making.
    Research is also leading to improved understanding of natural 
climate variability and its impacts. Current global climate models are 
improving our understanding of global climate sensitivity, ocean 
dynamics, climate feedbacks, and trends in extreme weather events and 
enhancing our ability to forecast climate on seasonal time scales and 
beyond. As models continue to improve, uncertainties in climate 
response will continue to be reduced resulting in a better 
understanding of current and future climate projections.

    Question 1a. Does NOAA make decisions on many matters governing 
resource management (e.g., fisheries management) where there are also 
significant uncertainties?
    Answer. NOAA develops fishery management plans (FMPs) and 
amendments, under authority of the Magnuson-Stevens Fishery 
Conservation and Management Act, based upon the best scientific 
information available (Section 301(a)(2)). Where there are significant 
uncertainties, NOAA supports using a precautionary approach.

    Question 1b. What metric is being used to document how much 
uncertainty exists and the progress being made to reduce uncertainties?
    Answer. NOAA is tracking research progress in reducing uncertainty 
through two performance measures under the Government Performance 
Results Act (GPRA):

        1. Reduce the Uncertainty in Model Simulations of the Influence 
        of Aerosols on Climate, and

        2. Reduce the Uncertainty in the Magnitude of the North 
        American (NA) Carbon Uptake.

    These high-level NOAA Corporate performance measures aim to track 
our skill in reducing uncertainty in estimates of North American carbon 
uptake from the atmosphere and in model simulations of aerosol impacts 
on climate. Improvements in measurements of carbon uptake will be 
important in validating carbon trading options at the regional level 
(e.g., carbon trading markets being discussed in CA and New England). 
The uncertainty of NOAA estimates of North American carbon uptake has 
decreased each year since 2003 as the NOAA North American carbon 
observation network approaches completion.

    Question 1c. What efforts are underway that relate one uncertainty 
to another and that amalgamate individual uncertainties into an overall 
uncertainty, determining whether an individual uncertainty is important 
or not?
    Answer. The overall uncertainty in the uptake of carbon by the 
North American continent is a suitable high-level measure that 
represents considerable effort to identify and attribute regional 
sources and sinks of carbon dioxide and other related gases. Several 
lower-level, more specifically focused measures are used to guide our 
efforts. Work is currently underway to employ both vertical 
observations from the network and analysis modeling to generate maps of 
regional emissions of carbon gases. The early maps, based upon the 
network at this time, are promising. They suggest a very real 
opportunity to provide, within a few years, emission and uptake maps on 
spatial and temporal scales that are useful for making regional 
decisions on managing carbon. As regional sources and sinks are 
identified and quantified, uncertainty decreases considerably. This 
effort is a necessary component of the North American Carbon Program, 
which involves a host of universities and many U.S. agencies, including 
NOAA, the National Aeronautics and Space Administration, Department of 
Energy (DOE), U.S. Department of Agriculture, U.S. Geological Survey, 
and the Environmental Protection Agency, among others. The goal is to 
build a system that can measure the transfer of carbon between land and 
atmosphere across the continent to vastly improve our understanding of 
its cycling. Subsequently, the U.S. Climate Change Science Program 
(CCSP) embraced this effort and a good part of its coordination is now 
conducted through the Carbon Cycle Interagency Working Group of the 
CCSP, of which NOAA is a major player. The idea was that measurements 
of ecosystem emissions or uptake (done or overseen by other agencies) 
should be verifiable with a vertical network of atmospheric 
observations (provided by NOAA and its partners) combined with coupled 
models that accounted for transport, fires, human emissions, and ocean 
influences. The greater understanding that comes with this effort will 
allow attribution of sources, lending considerable support to 
management and mitigation options for society.
    A second benefit of NOAA's carbon effort is the potential use of 
satellites to detect carbon emissions and uptake. Today, satellites are 
incapable of measuring CO2, with the accuracy and precision 
needed for such a study. However, that does not belie their potential 
use in the future, and their ability to provide high-frequency spatial 
coverage is unsurpassed. Because satellites measure total column 
amounts, success of satellite measurements requires a ground-based 
vertical network to support them. Satellites also require the 
calibrations of the ground based network, as sensors tend to drift, 
given that they operate in an inhospitable environment.
    A third area where we are focused on reducing uncertainty is 
through our work to improve understanding of the growth, distribution, 
and chemistry of aerosols in the atmosphere. Unlike carbon dioxide or 
other long-lived greenhouse gases, uncertainty in estimating the 
contribution of aerosols to global warming is significant. Current 
information suggests that aerosols have predominantly a cooling effect, 
and the effect could be large. Because aerosols are not well-mixed in 
the atmosphere, their effect on cooling or heating depends upon their 
distribution, size, and chemical composition. NOAA and its partners 
(DOE, University of Colorado, and others) currently are developing an 
observational record of aerosols at key locations around the world. We 
also are studying aerosol and related processes in the field and 
laboratory to improve our understanding of their effect on climate. By 
using these findings to improve aerosol-climate models, we 
systematically reduce the uncertainty in our estimate of their overall 
contribution to climate.
    Work is also progressing on the development of an index that 
separates uncertainties in climate projections into three components: 
(1) sub-seasonal: (2) seasonal; and (3) decadal. Once completed, this 
index will allow us to assess the uncertainties in climate projections 
for time scales ranging from days to decades.

    Question 2. What studies is NOAA undertaking to determine how 
available information on climate change is being and can be used, and 
what the role is of uncertainties in decision-making?
    Answer. The Regional Decision Support (RDS) program of NOAA's 
agency-wide Climate Mission Goal includes a focused research capability 
designed to address the role of climate and climate information in 
decision-making processes for climate-sensitive regions and sectors. 
The RDS effort harnesses the intellectual capabilities of NOAA and the 
external scientific community through a competitive grants process, and 
is conducted in partnership with NOAA's operational and transition 
activities to ensure that NOAA's climate services are well oriented to 
the needs and capabilities of the constituencies it serves. The RDS 
research effort is composed of two programs that address the use of 
climate information in decision-making: the Regional Integrated 
Sciences and Assessments (RISA) Program. and the Sectoral Applications 
Research Program (SARP). These programs complement and enhance each 
other, approaching the critical research issue of climate information 
for decision support from a regional and sectoral perspective. NOAA has 
more than a 10-year investment in research on the impacts and potential 
research applications associated with climate variability and change. 
This research has mostly been focused on shorter time scales (seasonal 
to interannual), but has provided useful insight into society's demand 
for and the potential value of climate information over multiple time 
scales, from intraseasonal (weeks/months) through decadal.
    In addition to the RDS research effort, NOAA is leading the 
development and production of two Climate Change Science Program (CCSP) 
Synthesis and Assessment Products (SAPs) that address the use of 
climate information and the role of uncertainty in decision-making:

        a) CCSP SAP 5.2: Best practice approaches for characterizing, 
        communicating, and incorporating scientific uncertainty in 
        decision-making; and

        b) CCSP SAP 5.3: Decision support experiments and evaluations 
        using seasonal to interannual forecasts and observational data. 

    NOAA supports similar work internationally by funding the 
International Research Institute for Climate Prediction, whose mission 
is to enhance society's capability to understand. anticipate, and 
manage the impacts of seasonal climate fluctuations in order to improve 
human welfare and the environment, especially in developing countries 
in Asia, Africa, and the Americas.

    Question 2a. If any studies of this nature have been completed by 
NOAA, what were the findings?
    Answer. Studies conducted by the NOAA RDS effort have addressed the 
use of climate information in a suite of diverse regions and sectors, 
including the following:

              Sectors                            U.S. Regions
Natural hazard preparedness          Pacific Islands
Agriculture and food security        Pacific Northwest
Water resource management            California
Coastal management                   Southwest
Public health                        Southeast (two regions)
Urban                                New England
Ecosystem management                 Intermountain West

    There are certain sectors where NOAA has been more active, and thus 
has more knowledge of the role of climate and climate information, 
including the nature and implications of uncertainty. Examples of such 
sectors include fire management, public health, water management, and 
natural hazards preparedness. Other sectors, such as coastal, urban, 
and conservation, are beginning to articulate their interest in 
climate. Two sector-specific examples of NOAA's work follow:

   Climate information is being used to predict pre-season fire 
        potential for the United States. NOAA-funded climate 
        researchers, USDA-Forest Service, and the National Interagency 
        Coordination Center have developed a series of National 
        Seasonal Assessment Workshops to enhance fire preparedness, 
        prescribed fire management, and awareness of the connections 
        between climate and fire. Participants synthesize and analyze 
        climate, forestry, and fire science information to predict fire 
        potential for the upcoming fire seasons.

   Climate information is being used to a limited extent by 
        municipal water managers. Through an ongoing NOAA-supported 
        study, we have found that municipal planners use a diverse set 
        of climate information, including climate/water indices, and 
        some use paleo data to inform thinking about long-term climate. 
        Some municipal water providers create their own system-specific 
        indices to determine what might trigger water supply and demand 
        issues for their water system.

    Specific findings of the RDS studies can be found on the websites 
for the RISA and SARP activities: http://www.climate.noaa.gov/cpo_pa/
risa/ and http://www.climate.noaa.gov/cpo_pa/sarp/. Although the 
findings of NOAA's research vary depending on the characteristics of 
the decision-making challenge at hand, this body of work underscores 
the potential value of climate information for decision-making, and the 
demand for climate information.
    In addition. there are some overarching lessons that have been 
generated regarding the relationship between humans and climate, and 
the characteristics of effective decision support efforts that take 
uncertainty into account. Examples include the following:

   Climate forecasts are often just one tool utilized by 
        decisionmakers in addressing a resource management challenge. 
        Climate forecasts are not deterministic; the utilization of 
        climate information by decision-makers requires a synthesis of 
        science, practical resource management strategies and an 
        anticipation of the requirements for the health and welfare of 
        human society and the environment.

   Effective climate decision support systems include sustained 
        processes for interaction and collaboration between the 
        producers and users of climate information. Users include 
        decision-makers such as farmers, water managers, public health 
        and safety managers and others responsible for managing 
        climate-sensitive sectors.

   Climate information often requires specific tailoring before 
        it can be utilized by users. For example. climate-based 
        forecasts of total water volume might be useful for one type of 
        water resource decision, but another type of decision might 
        require information about the onset of seasonal precipitation.

   Communication methods must take into account the various 
        levels of uncertainty associated with both the climate 
        information and the context within which decisions are being 
        made (i.e., markets, culture, other environmental stressors).

    Question 2b. How does NOAA plan to build on these efforts to assist 
the public and government decisionmakers?
    Answer. The NOAA Climate Goal and its component programs are 
dedicated to providing the Nation with climate services through an 
``end-to-end'' process (observations, analysis, prediction, 
application, delivery), and over all time scales. The NOAA Climate 
Program Office improves climate services through its five components:

   The Climate Observations and Analysis (COA) Program--The COA 
        program's goal is to describe and understand the state of the 
        climate system through integrated observations, analysis, and 
        data stewardship.

   The Climate Forcing (CF) Program--The CF program's goal is 
        to reduce uncertainty in the information on atmospheric 
        composition and feedbacks that contribute to changes in Earth's 

   The Climate Predictions and Projections (CPP) Program--CPP 
        program's goals are to provide (1) climate forecasts for 
        multiple time scales to enable regional and national managers 
        to better plan for the impacts of climate variability, and (2) 
        climate assessments and projections to support policy decisions 
        with objective and accurate climate change information.

   The Climate and Ecosystems (C&E) Program--C&E program's goal 
        is to understand and predict the consequences of climate 
        variability and change on marine ecosystems.

   The Regional Decision Support (RDS) Program--RDS program's 
        goal is to build effective bridges between users and producers 
        of climate information so that public and private sector 
        decision-makers have access to and participate in the creation 
        of new knowledge, processes, tools, and products to improve 
        risk management, response, and mitigation in sectors sensitive 
        to climate variability and change.

    The National Integrated Drought Information System (NIDIS) is an 
example of an end-to-end process covering multiple time scale and 
climate program components. The vision for NIDIS is a dynamic and 
accessible drought information system that provides users with the 
ability to determine the potential impacts of drought and the 
associated risks they bring, and the decision support tools needed to 
better prepare for and mitigate the effects of drought. Implementation 
of NIDIS will require:

   Building a national drought monitoring and forecasting 

   Creating a drought early warning system;

   Providing an interactive drought information delivery system 
        for products and services, including an Internet portal and 
        standardized products (databases, forecasts, Geographic 
        Information Systems (GIS), maps, etc.); and

   Designing mechanisms for improved interaction with the 
        public (education materials, forums. etc.).

    Question 3. In your written testimony, on page 3, you list various 
types of assessment efforts that NOAA has been involved in. You do not 
mention that NOAA played an important role in the various sectoral, 
regional, and national components of the U.S. National Assessment, 
including leading the assessment of the likely impacts on coastal areas 
and marine resources and sponsoring several regional studies. Can you 
explain why the important results that emerged from these studies were 
not discussed in your testimony?
    Answer. The work from the U.S. National Assessment report on coasts 
and marine resources is mentioned and cited in the testimony. For 
example, on page 4 of the testimony the summary article by Scavia et 
al. (2002) is referenced. Several studies cited in the U.S. National 
Assessment report (e.g., Tynan and DeMaster, 1997; Brown, 1997) are 
also cited in the testimony. The U.S. National Assessment report on 
coasts and marine resources was published in 2000. The science on this 
topic is rapidly evolving. The testimony provides a synopsis of 
important recent findings, especially over the 6 years since the 2000 
report was published on such topics as ocean acidification, which had 
not been well-studied at the time of the U.S. National Assessment.

    Question 4. The regional, sectoral, and national results of the 
National Assessment formed the basis for the chapter on impacts and 
adaptation in the U.S. Climate Action Report 2002 that was endorsed by 
all agencies before being submitted to the U.N. Framework Convention on 
Climate Change as the official government position. Have any recent 
scientific developments caused NOAA to reevaluate its positions 
regarding the potential consequences of climate variability and change, 
both based on the national level and for the regional and sectoral 
efforts that it led and/or sponsored?
    Answer. Recent research results from prominent Earth system 
scientists are garnering considerable attention, particularly in the 
area of sea level rise, and potential trends in extreme events such as 
hurricanes, floods, and drought. These results warrant further 
attention, investigation, and dialogue across the Federal agencies and 
in partnership with Congress. For example, the experience over the past 
several years throughout the U.S. West with severe sustained drought 
has raised a broad range of issues ranging from drought management to 
assessing long-term drought trends, which have important implications 
for fire and water management, and ecosystem sustainability. NOAA is 
responding in the context of the development and cross-agency 
implementation of the National Integrated Drought Information System 
(MIDIS). We expect there will be more such calls for a range of climate 
information services responsive to the needs of local, state, and 
Federal managers.

    Question 5. In your written testimony, you indicate on page 5 that 
``Remarkably only a few documented extinctions occurred in terrestrial 
and marine ecosystems during the ice age cycles . . . .'' You indicate 
that one reason for this was likely that, overall, the climatic changes 
were ``slow compared to the changes in the current millennium.''
    Given that the human influence has been primarily during the latter 
20th century rather than over the entire millennium, would it be fair 
to say that changes during the last glacial period were very slow 
compared to the changes over the past 50 years, and that the rate of 
change might well be so fast that assurances that species survived 
glacial cycling likely provide no assurance that there will be 
remarkably few extinctions as a result of human-induced warming?
    Answer. Yes, it would be fair to say that survival of many species 
during glacial cycling likely provides no assurance that there will be 
few extinctions as a result of human-induced warming. Two aspects of 
human-induced warming might cause species to become extinct in the 
future. One is the rapid rate of human-induced warming, roughly ten 
times faster than the rate observed in the paleoclimate record (the 
average Earth temperature warmed 4+C in a few thousand years at the end 
of the last Ice Age.\2\ compared to the warming of 0.7+C in the past 
100 years.\3\, \4\ The second aspect is that climate is 
expected to reach conditions outside the range (of temperature, 
precipitation, ocean pH, and ocean and atmosphere circulation) 
experienced during the glacial cycles.\5\, \6\ Unlike 
glacial times, future changes will occur in a world with 6 billion 
people within ecosystems now fragmented by human land use.
    \2\ Imbrie, J.I., E.A. Boyle, S.C. Clemens, A. Duffy, W.R. Howard, 
G. Kukla, et al. 1992. On the structure and origin of major glaciation 
cycles: 1. Linear responses to Milankovitch forcing. Paleoceanography. 
7: 701-738.
    \3\ Jones, P.D., T.J. Osborn, K.R. Briffa, C.K. Folland, E.B. 
Horton, L.V. Alexander, et al. 2001. Adjusting for sampling density in 
grid box land and ocean surface temperature time series. Journal of 
Geophysical Research. 106: 3371-3380.
    \4\ Parker, D.E., C.K. Folland and M. Jackson 1995. Marine surface 
temperature observed variations and data requirements. Climatic Change, 
31: 559-600.
    \5\ COHMAP Project Members 1988. Climate changes of the last 18,000 
years: Observations and model simulations. Science, 241: 1043-1052.
    \6\ Houghton, J.T. et al. 2001. Climate Change 2001: The Scientific 
Basis, Cambridge University Press.

    Question 6. A recent paper appearing in Nature (Grottoli et al.) 
indicates that a species of coral has been found that seems to be able 
to adapt to higher temperatures. In your testimony, you indicated that 
both the temperature increase and ocean acidification are threats to 
the coral. Is this newly identified species of coral also able to 
survive the ocean acidification that will be caused by the higher 
CO2 concentrations?
    Answer. Grottoli et al. \7\ found that one of the corals they 
studied, the branching coral Montipora capitata, was able to switch to 
feeding on zooplankton for its predominant food source. This allows it 
to better survive a bleaching event, but does not change its tendency 
to bleach. A recent study \8\ on the impacts of elevated carbon dioxide 
on coral photosynthesis and calcification included M. capitata as part 
of the coral assemblage investigated. Although M. capitata appears to 
survive bleaching better relative to other corals \7\ it is not immune 
from the effects of ocean acidification. Rather, M. capitata was found 
to exhibit a pronounced reduction in calcification rate in response to 
elevated carbon dioxide.
    \7\ Grottoli, A.G., L.J. Rodrigues, and J.E. Palardy. 2006. 
Heterotrophic plasticity and resilience in bleached corals. Nature. 
440: 1186-1189.
    \8\ Langdon, C., and M.J. Atkinson. 2005. Effect of elevated 
pCO2 on photosynthesis and calcification of corals and 
interactions with seasonal change in temperature/irradiance and 
nutrient enrichment. Journal of Geophysical Research--Oceans. 110(C9): 

    Question 7. In your written testimony you indicate that, apparently 
associated with an increase in air temperatures, ``the density of krill 
. . . has decreased by more than 90 percent in the region since 1976'' 
and that this is having associated impacts on other species. Is this 
evidence of a dangerous anthropogenic interference with one of nature's 
key ecosystems?
    Answer. The reasons for the decline in krill populations in 
Antarctica are not clear and cannot be explained fully. Many factors 
are believed to have contributed to the declines. We know that the 
Southern Ocean is undergoing a warming trend, which likely influences 
ocean circulation and sea-ice dynamics. Although these factors likely 
affect krill populations, the definitive link between climate change 
and anthropogenic interference has not been established. Due to its 
relative isolation, the direct anthropogenic effects in Antarctica are 
substantially less than in other parts of the world. It also is clear 
that the decline in krill populations is not directly related to 
overfishing. The present annual harvests in Antarctica are around 
100,000 tonnes, while the International Commission for the Conservation 
of Antarctic Marine Living Resources precautionary catch limits are 
more than 4 million tonnes. The catch limits are based on relatively 
recent surveys. There is considerable debate in the scientific 
community concerning the role indirect effects may have played in this 
ecosystem. As my testimony indicated, reduced sea ice is generally 
believed to have played a major role in reduced krill populations. 
Other causal effects are difficult to quantify. Evidence suggesting 
anthropogenic interference with the Antarctic ecosystem is not clear 
and considerable debate exists among scientists. We are addressing 
these concerns, but it will be some time before cause and effect is 
clearly delineated.

    Question 7a. If not at 90 percent, at what point would it be that 
NOAA management would strongly advocate publicly and with the 
Administration for actions to slow and limit further changes in the 
    Answer. NOAA will continue to carry out our mission to ``understand 
and describe climate variability and change to enhance society's 
ability to plan and respond'' through our research, observations, and 
modeling capabilities, but we do not focus on advocacy. As a key part 
of the U.S. Climate Change Science Program, we are working on 
developing synthesis and assessment products intended to provide the 
best possible scientific information, developed by a diverse group of 
climate experts, for the decision community. These reports are designed 
to address a full range of scientific questions and evaluate options 
for responses that are of greatest relevance to planners and decision-
 Response to Written Questions Submitted by Hon Frank R. Lautenberg to 
                         Dr. Syun-Ichi Akasofu
    I am glad to have this opportunity to express my thoughts on the 
global warming issues in more detail, since it was not easy to do so 
during the testimony due to the time constraints. I have tried to 
answer all your questions.
    If you have further questions, please do not hesitate to contact 
me. Also, I am more than happy to explain more when I come to 
Washington, D.C., next time.
    Question 1. Regarding Figure 1 in your written testimony--Why is it 
that the graph indicating sources of energy ends at 1985 and does not 
show the associated increase of energy use with temperature up to the 
    Answer. I received the invitation to testify while I was in Tokyo 
and had only a few days to prepare the written document by working with 
my staff in Fairbanks, Alaska, via phone and fax. The original Figure 1 
in my testimony was prepared under these difficult circumstances.

    Question 1a. Could you please provide an updated plot that extends 
the energy record to at least the year 2000, or preferably extends both 
the emissions and temperature records to 2005?
    Answer. I am glad to have an opportunity now to provide you with an 
updated version of Figure 1, which is now Figure A in this 
correspondence. I also prepared a new one with the CO2 data 
alone (Figure B), which I wanted to use to begin with. Please notice 
that the range of temperature changes is much greater in the Arctic 
than the global average provided by the IPCC Reports.

    Question 2. In Figure 1, is the mid-20th century jump (i.e., 
increase and then decrease) in the Arctic temperature record that you 
show a usual occurrence; that is, is there any indication that such 
sudden and short duration warming periods have occurred previously?
    Answer. Before 1850 or so, there were not many thermometers in the 
whole world. Therefore, we have to rely on proxy data. Unfortunately, a 
1000-year temperature record based on the tree ring analysis by Mann 
(the so-called `hockey stick') used most frequently and prominently in 
IPCC Reports and others, is now very controversial; please see your 
item 7.
    The most reliable data for the past are deduced from ice cores 
(O18). We are fortunate to have such a high-resolution (in time) data 
from Severnaya Zemlya (Figure 5 in my testimony, which is reproduced 
here as Figure C). There have been a number of fluctuations, large and 
small, superposed on a linear increase (which is discussed in 
conjunction with your Item 8).
    Please note that the top, middle, and bottom traces agree 
reasonably well, confirming the accuracy of all the data shown.

    Question 3. Might there be problems with the data set that is used 
to generate this record, especially given the limited time over which 
observations are available in the Arctic? Could you supply some 
indication of the number of measurements going into the Arctic record 
and the percentage coverage of the Arctic that is represented over time 
by this record?
    Could it be that only one part of the Arctic was as warm in the mid 
20th century as it is currently and other parts that did not warm were 
not represented in the temperature record of Polyakov?
    Answer. The top of Figure D shows the same temperature record as 
that of Figure A (or Figure 1 of my testimony). Please note that added 
to it, as an insert, is the distribution of the stations from which 
data was used. They are distributed mostly along the entire arctic 
coast. (Russia actually kept excellent temperature records even in 
Siberia and recorded carefully watched changes in natural phenomena, 
better than some other places in the world.)

    The bottom of Figure D shows sea water temperature data. They are 
taken from the middle of the Arctic Ocean as the insert shows.
    Please note that the temperature record similar to figure A is 
shown on page 23 of the ACIA Report ``Impact of a Warming Arctic'' 
(Figure 4 of my testimony); it includes continental data in the Arctic. 
It shows a larger increase after 1970 than in 1940, because a very 
prominent warming occurred in the continental Arctic, which is 
disappearing during the last decade or so, as shown in Figure 3 of my 

    Question 4. With the Arctic indicated to be as warm in the mid-20th 
century as at present, and with that warming lasting for a time 
comparable to the time of the current warming, is there evidence that 
indicates that the same types of changes in sea ice, permafrost, 
glacial melting, species shifts, etc. occurred as we are seeing at 
present? Do the Indigenous elders recall such warm periods and the 
appearance of the new birds and other species that are now occurring in 
the Arctic?
    Answer. Sea ice: The only reliable, long-term data before 1950 are 
observations of the southern ice edge in the Norwegian Sea (Figure E; 
my testimony Figure 7b). Please note that the range of changes during 
1920-1960 (corresponding to what you term `the mid-20th century jump' 
was much larger than the present change after 1970; the present change 
is much smaller than that during the mid-20th century in the Norwegian 
Sea. Please note also a linear change similar to the ice core change 
that will be discussed in your Item 8.

    Permafrost: Figure F shows the best available temperature data on 
permafrost, from both Siberia and Fairbanks. Please note that the 
temperature was decreasing until 1970, in spite of the fact that the 
amount of CO2 began to increase rapidly in about 1940. 
Permafrost temperature closely follows air temperature (please compare 
Figure F with Figure A).
    Glaciers: Old Russian records show that many Alaskan glaciers have 
been receding since 1800 or earlier (Figure 7a in my testimony). The 
recession did not start in 1970; please see also Figure G. Changes in 
the European Alps are similar to it.

    Many recent TV programs show large blocks of ice falling off the 
glacier terminus, implying that this phenomenon is a manifestation of 
global warming. Most people do not realize that glaciers are actually 
``rivers of ice'' (where ice flows) and that ice has been falling off 
glacier termini for thousands and thousands of years.
    Others: Some species are obviously quite sensitive to temperature 
changes; fish are quite sensitive to sea water temperature changes. I 
am not an expert on such issues, but happen to have an interesting 
figure (Figure H), which shows changes of fish populations in the 
Pacific. It seems that such changes are a common occurrence.

    Question 5. In your written testimony you state that ``It is also 
important to note that both the Arctic and global temperatures began to 
decrease in about 1940, when our release of greenhouse gases began to 
increase rapidly. Thus the increase-decrease between 1920 and 1970 must 
be natural change.'' The most often mentioned natural factors that 
could be responsible for a warming are a reduction in the amount of 
volcanic aerosol and an increase in solar radiation. If these factors 
are indeed responsible for this warming, it would seem to lead to the 
conclusion that the Arctic climate is very, very sensitive to slight 
changes in the amount of energy driving the climate system, in that the 
volcanic and solar influences, in terms of Watts per square meter, have 
been relatively small. Thus, should not your assertion that these 
changes are natural make us very, very concerned about the climatic 
changes that lie ahead given the large changes in atmospheric radiation 
being caused by the continuing human-induced increases in the 
concentrations of greenhouse gases?

    Question 6. The detection and attribution studies reported on by 
the IPCC conclude that the warming prior to about 1940 was likely due 
partly to natural factors and partly to the release of greenhouse 
gases, and that the subsequent cooling was due mainly to the increasing 
emissions of SO2 and possibly a slight diminution in solar 
radiation and return of volcanic eruptions. These carefully done 
detection and attribution studies, endorsed by the IPCC, make clear 
that such analyses must include consideration of all forcing factors 
(and that there are natural and human-induced factors that induce 
warming and other factors that can induce cooling). It therefore seems 
to be quite a jump to suggest that the mid-century part of the record 
must be entirely due to natural factors without considering the human 
influences also likely to have exerted influences throughout the 20th 
century. What steps does your analysis take to conclude that the full 
set of human-induced factors is not having an influence?
    Answer to Questions 5 and 6. I believe that all the IPCC GCMs 
consider effects of observed volcano effects (past major eruptions), 
solar output changes, aerosol effects (SO2), etc., and their 
positive/negative feedback effects as well, quantitatively with the 
best knowledge available. However, they cannot reproduce the mid-20th 
century jump. It is very hard to explain the 1940-1970 decrease, 
particularly since CO2 began to increase rapidly at that 
time; the initial increase is also hard to explain. Therefore, at this 
stage, I must come to the same conclusion I did earlier during my oral 
testimony, as I describe below again.
    We always come up with interesting ideas about how to explain 
natural phenomena, but if they fail the quantitative tests, we have to 
abandon them. This happens every day in science. If the idea has failed 
the test and knowing that the test was conducted with the best 
knowledge available at the time, scientists should not pretend or claim 
that their interesting ideas are still alive. Such interesting but 
unproven ideas belong to science fiction. During my testimony I showed 
that the continental arctic warming during 1970-2000 belongs to that 
category (Figure 2 of my testimony), too. Nothing is 100 percent 
certain in climatology, but I believe that the Senate subcommittee 
members did not want `noncommittal' statements from the panel members. 
On the other hand, if the idea passes the test, I am happy to support 
the idea. Since I am not a climatologist, I have no hang-up in either 
camp. What I can say as an auroral physicist is that the present 
climatology is very abnormal.
    As you may know, the ``mid-20th century jump'' is a northern 
hemisphere phenomenon, not a southern hemisphere phenomenon. Thus, it 
is NOT A GLOBAL phenomenon. This is very clear in the paper by Jones, 
which became the basis of the IPCC Report. In fact, it appears to be a 
phenomenon above 40+ latitude in the northern hemisphere, so that it is 
doubtful that it is really a global phenomenon. It may well be that 
this is why the GCMs cannot reproduce it as the greenhouse effect! 
(Just as is the case of the continental arctic warming!)
    Some people argue that the GCMs have not advanced enough to be used 
for such tests. If so, they would logically also have to doubt the 
basis of the Kyoto protocol on global warming. There may be some 
problems with prediction, because we have to assume the amount of 
CO2 released in the future. On the other hand, we are using 
GCMs for what we call ``hind-casting'' based on the observed CO2 
data, and the GCMs are accurate enough for our purpose; furthermore, we 
are using 14 GCMs.

    Question 7. You indicate on page 1 of your written testimony that 
``It is incorrect to conclude that the present warming in the Arctic is 
due entirely to the greenhouse effect caused by man.'' In answer to a 
question, you indicated that such assertions were being made mainly by 
the media and did not indicate any scientific assessments that were 
making this assertion. Is it your opinion, therefore, that we can rely 
on the IPCC and ACIA assessments, even though there may be some 
misimpressions given by some in the media, or are you suggesting that 
the assessments are also flawed?

    Question 7a. If the latter, please provide specific examples where 
you think the complete picture is not being presented. What part of the 
warming do you judge to be human-induced and what fraction natural, and 
what is your estimate of how this ratio has changed over time?
    Answers to Questions 7 and 7a. Both the IPCC and ACIA Reports 
served in raising awareness of the CO2 problem. However, I 
am not very happy about the ``tactics'' they used (you must have heard 
about some of the complaints from the contributors). There was no 
``refereeing'' like scientific papers for scientific journals. During 
our testimony, Dr. Reiter was quite critical of one chapter on malaria, 
saying that the contents was very poor. You will recall that this was 
also a major complaint by Dr. Michael Crichton during his testimony in 
one of the earlier hearings. As I also mentioned in my testimony, the 
present climate research presented by the IPCC Report is not taking the 
normal scientific practice. For example, Mann's ``hockey stick'' figure 
was so appealing for the purpose of raising awareness of the greenhouse 
effect, it was prominently used by the IPCC Reports. Mann's figure 
shows neither the Medieval warming nor the Little Ice Age, so that some 
scientists questioned its accuracy. Finally, two Canadian experts in 
statistics analyzed the same data (which they said Mann was very 
reluctant to make available; as you may know, Congress finally demanded 
he submit the data) and showed that there is no ``hockey stick'' in the 
data (Figure I). I am afraid that Mann's results, the IPCC 
``flagship,'' may turn out to be a flawed case. Dr. Robert Correll used 
it in his testimony without telling us that there is some problem with 
it, even if he believes its accuracy. It is unfortunate that it gave 
the impression that the greenhouse effect did indeed take off.

    In science, new results should be scrutinized by the community, and 
if they survive the scrutiny, they become scientific facts. It is my 
belief that the IPCC way of mobilizing hundreds of scientists is not a 
good practice in science. I wonder how many of the IPCC contributors 
can defend Mann's work, in spite of the fact that they are the co-
    Another important issue: as I testified, many climatologists use 
satellite data, which became available only in the 1970s, when the 
latest rise in temperature occurred. Therefore, what they report is 
naturally related to the temperature rise. Many of the presently active 
scientists were born in the 1960s and 1970s, so that it is natural for 
them to assume that the temperature rise has been happening during 
their whole life. However, in terms of genuine climatology, it is but 
an instant. That is why I want to call them ``instant climatologists''; 
many of them do not want to work on the mid-20th century jump, since it 
will take a great deal of effort to get data similar to what satellites 
can provide readily. In order to work on climatology, I am asking my 
colleagues that they should try to get at the very least data that 
spans a few hundreds years. Climatology used to be like anthropology. 
However, after the advent of satellites and computers, it has become an 
instant climatology.
    Now, the present problem is that the media and many special 
interest groups take the scientific data after the 1970s as scientific 
fact for the greenhouse effect. As soon as results associated with the 
rising temperature are reported in scientific papers (or even before), 
they are immediately reported by them as scientific facts proving the 
greenhouse effect, confusing the term global warming as synonymous with 
the greenhouse effect. Many media people do not have enough scientific 
background on the greenhouse effect. I might add that scientists who 
doubt or criticize greenhouse studies are demonized by the media these 
days. All this is a very abnormal circumstance in science, I am afraid. 
Whenever an issue is raised, the media defends itself by saying that 
hundreds of scientists joined in the preparation of the IPCC Reports. I 
hope you can understand the problem.
    Distinguishing between natural and manmade components of climate 
change is a very difficult task, but IARC scientists are challenging 
the problem, since this is the one way to ``reduce uncertainty in 
climate change predictions''; please see your item 8.

    Question 8. In your Figure 7b (top) you include a linear trend line 
beginning in 1760 and going to the year 2000. Why do you assume that 
human-induced influences should be linear, especially given the 
temporal and spatial variations in the forcing terms, interactions 
these might have for the atmospheric and oceanic circulations, etc.?
    Answer. The linear line in Figure C is NOT meant to be human-
induced influence at all. It is only recently that the ice core (O18) 
analysis provided us with proxy data for the last 200 years. The longer 
the analysis period is, the more accurate the baseline becomes, on 
which various fluctuations are superposed. In the 100-year data (Figure 
A), we could not see clearly the linear trend (the ACIA Report, p. 23, 
used the 100-year average value as the baseline). There is little doubt 
about the presence of the linear trend in the 200-year data.
    As you correctly observed, there is no way to explain the linear 
trend by the greenhouse effect. I speculate that it is a natural 
change; the sea ice data and some other O18 data show similar linear 
trends. Are we still recovering from the Little Ice Age?
    IPCC Reports say that the global temperature increased by 0.6+C 
during the last century, and it implies that the increase is caused by 
the greenhouse effect. If the linear change continued until recently, 
and if it were indeed to be natural change, the greenhouse effect will 
not be a large fraction of the 0.6+C. This is the uncertainty we have 
to face in climate change research at the present time. We have to 
isolate the linear trend and other natural changes in detail and find 
out the real contribution of the greenhouse effect.

    Question 8a. Might it be that conditions continue in one state for 
a while and then flip, for example, once the ice melt reaches a certain 
amount or once temperatures in key regions exceed the freezing point?
    Answer. What you are referring to may be what we call the 
``threshold'' point. For example, many researchers told me earlier that 
sea ice in the Arctic Ocean off the Alaskan coast had crossed ``the 
point of no-return'' during the summer months based on satellite data. 
However, sea ice was much closer to the Alaskan coast in 2005 than in 
2004 or 2003. It came back last year.
    In principle, what you say may occur; however, I am not sure if the 
present climatology can predict accurately the threshold point of any 
climate change phenomena.

    Question 9. Although climate models may not provide sufficiently 
accurate representations of the spatial distribution of warming, do you 
agree that they do include representations of the overall thermodynamic 
and dynamic influences, so that the global integral of the influence, 
which is presumably based on the overall balance of energy, of 
increasing concentrations of greenhouse gases, and of other factors is 
roughly correct? What improvements do you think are most needed in the 
available climate models?
    Answer. The physics of the greenhouse effect is sound and clear; 
that is not the question. The questions are: (1) how much did the 
greenhouse effect contribute to the 0.6+C increase and the mid-20th 
century jump, and (2) how much will the temperature increase by 2100, 
more than 6+C or less than 1+C? (When I say this, some scientists 
immediately argue with me and say that I deny the greenhouse effect. 
They forget the normal scientific practice, and the IPCC must have 
created such an unscientific atmosphere.)
    At the International Arctic Research Center (IARC), our main 
objective is to ``reduce uncertainty in future climate change 
predictions.'' Certainly, our progress in science will improve the 
modeling effort. On the other hand, we should not forget that the 
Earth's temperature fluctuates all the time. We cannot understand the 
cause(s) of the Big Ice Age, the Medieval warming (1000-1300 AD, almost 
as warm as the present time), and the Little Ice Age (1400-1900?), in 
addition to the fact that the temperature was higher at the beginning 
of the present interglacial period and some other interglacial periods 
when only anthropoids were present on Earth. This is what Dr. Thomas 
was stressing during his testimony. There is no reason to assume that 
the linear change suddenly stopped after 1900. We have to identify and 
subtract natural change from the on-going changes; the rest will give 
us some idea about the greenhouse effect.
    I am afraid that this communication is getting too heavy, so that I 
have put two cartoons at the end. I find that cartoonists observe well 
the present situation.