[House Hearing, 111 Congress]
[From the U.S. Government Publishing Office]
A RATIONAL DISCUSSION OF CLIMATE CHANGE:
THE SCIENCE, THE EVIDENCE, THE RESPONSE
=======================================================================
HEARING
BEFORE THE
SUBCOMMITTEE ON ENERGY AND
ENVIRONMENT
COMMITTEE ON SCIENCE AND TECHNOLOGY
HOUSE OF REPRESENTATIVES
ONE HUNDRED ELEVENTH CONGRESS
SECOND SESSION
__________
NOVEMBER 17, 2010
__________
Serial No. 111-114
__________
Printed for the use of the Committee on Science and Technology
Available via the World Wide Web: http://www.science.house.gov
----------
U.S. GOVERNMENT PRINTING OFFICE
62-618 PDF WASHINGTON : 2010
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Washington, DC 20402-0001
COMMITTEE ON SCIENCE AND TECHNOLOGY
HON. BART GORDON, Tennessee, Chair
JERRY F. COSTELLO, Illinois RALPH M. HALL, Texas
EDDIE BERNICE JOHNSON, Texas F. JAMES SENSENBRENNER JR.,
LYNN C. WOOLSEY, California Wisconsin
DAVID WU, Oregon LAMAR S. SMITH, Texas
BRIAN BAIRD, Washington DANA ROHRABACHER, California
BRAD MILLER, North Carolina ROSCOE G. BARTLETT, Maryland
DANIEL LIPINSKI, Illinois VERNON J. EHLERS, Michigan
GABRIELLE GIFFORDS, Arizona FRANK D. LUCAS, Oklahoma
DONNA F. EDWARDS, Maryland JUDY BIGGERT, Illinois
MARCIA L. FUDGE, Ohio W. TODD AKIN, Missouri
BEN R. LUJAN, New Mexico RANDY NEUGEBAUER, Texas
PAUL D. TONKO, New York BOB INGLIS, South Carolina
STEVEN R. ROTHMAN, New Jersey MICHAEL T. McCAUL, Texas
JIM MATHESON, Utah MARIO DIAZ-BALART, Florida
LINCOLN DAVIS, Tennessee BRIAN P. BILBRAY, California
BEN CHANDLER, Kentucky ADRIAN SMITH, Nebraska
RUSS CARNAHAN, Missouri PAUL C. BROUN, Georgia
BARON P. HILL, Indiana PETE OLSON, Texas
HARRY E. MITCHELL, Arizona
CHARLES A. WILSON, Ohio
KATHLEEN DAHLKEMPER, Pennsylvania
ALAN GRAYSON, Florida
SUZANNE M. KOSMAS, Florida
GARY C. PETERS, Michigan
JOHN GARAMENDI, California
VACANCY
------
Subcommittee on Energy and Environment
HON. BRIAN BAIRD, Washington, Chair
JERRY F. COSTELLO, Illinois BOB INGLIS, South Carolina
EDDIE BERNICE JOHNSON, Texas ROSCOE G. BARTLETT, Maryland
LYNN C. WOOLSEY, California VERNON J. EHLERS, Michigan
DANIEL LIPINSKI, Illinois JUDY BIGGERT, Illinois
GABRIELLE GIFFORDS, Arizona W. TODD AKIN, Missouri
BEN R. LUJAN, New Mexico RANDY NEUGEBAUER, Texas
PAUL D. TONKO, New York MARIO DIAZ-BALART, Florida
JIM MATHESON, Utah
LINCOLN DAVIS, Tennessee
BEN CHANDLER, Kentucky
JOHN GARAMENDI, California
BART GORDON, Tennessee RALPH M. HALL, Texas
CHRIS KING Democratic Staff Director
SHIMERE WILLIAMS Democratic Professional Staff Member
ADAM ROSENBERG Democratic Professional Staff Member
JETTA WONG Democratic Professional Staff Member
ANNE COOPER Democratic Professional Staff Member
ROBERT WALTHER Democratic Professional Staff Member
DAN BYERS Republican Professional Staff Member
TARA ROTHSCHILD Republican Professional Staff Member
JANE WISE Research Assistant
ALEX MATTHEWS Research Assistant
C O N T E N T S
November 17, 2010
Page
Witness List..................................................... 2
Hearing Charter.................................................. 3
Opening Statements
Statement by Representative Brian Baird, Chairman, Subcommittee
on Energy and Environment, Committee on Science and Technology,
U.S. House of Representatives.................................. 8
Written Statement............................................ 10
Statement by Representative Ralph M. Hall, Ranking Minority
Member, Committee on Science and Technology, U.S. House of
Representatives................................................ 11
Written Statement............................................ 13
Statement by Representative Bob Inglis, Ranking Minority Member,
Subcommittee on Energy and Environment, Committee on Science
and Technology, U.S. House of Representatives.................. 13
Written Statement............................................ 15
Prepared Statement by Representative Jerry F. Costello,
Subcommittee on Energy and Environment, Committee on Science
and Technology, U.S. House of Representatives.................. 16
Panel I:
Dr. Ralph J. Cicerone, President, National Academy of Sciences
Oral Statement............................................... 17
Written Statement............................................ 19
Biography.................................................... 24
Dr. Richard S. Lindzen, Alfred P. Sloan Professor of Meteorology,
Department of Earth Atmospheric and Planetary Science,
Massachusetts Institute of Technology
Oral Statement............................................... 25
Written Statement............................................ 27
Biography.................................................... 50
Dr. Gerald A. Meehl, Senior Scientist, National Center for
Atmospheric Research
Oral Statement............................................... 51
Written Statement............................................ 53
Biography.................................................... 58
Dr. Heidi M. Cullen, CEO and Director of Communications, Climate
Central
Oral Statement............................................... 58
Written Statement............................................ 64
Biography.................................................... 73
Discussion
The Impacts of CO2 Increases on Temperatures........ 73
Humans Have Caused Increases in Atmospheric CO2........ 74
The Greater Proportion of Record High Temperatures............. 74
Quantifying Climate Sensitivity and Water Vapor................ 76
The Common Cause for Clean Energy Development.................. 78
Climate Skepticism............................................. 80
Panel II:
Dr. Patrick J. Michaels, Senior Fellow in Environmental Studies,
Cato Institute
Oral Statement............................................... 85
Written Statement............................................ 89
Biography.................................................... 99
Dr. Benjamin D. Santer, Atmospheric Scientist, Program for
Climate Model Diagnosis and Intercomparison, Lawrence Livermore
National Laboratory
Oral Statement............................................... 99
Written Statement............................................ 104
Biography.................................................... 104
Dr. Richard B. Alley, Evan Pugh Professor, Department of
Geosciences and Earth and Environmental Systems Institute, The
Pennsylvania State University
Oral Statement............................................... 115
Written Statement............................................ 120
Biography.................................................... 125
Dr. Richard A. Feely, Senior Scientist, Pacific Marine
Environmental Laboratory, National Oceanic and Atmospheric
Administration
Oral Statement............................................... 126
Written Statement............................................ 129
Biography.................................................... 134
Discussion
Ocean Acidification and Coral Damage........................... 134
Measuring Glacial Changes...................................... 135
Evidence of Anthropogenic Change............................... 135
Ocean Acidification and Economic Impacts....................... 141
Science and the Federal Government............................. 143
More on Glaciers and Evidence of Anthropogenic Change.......... 144
Fossil Fuel Resources and Climate Change....................... 148
The Impacts of Current CO2 Emissions................ 151
Panel III:
Rear Admiral David W. Titley, Oceanographer and Navigator of the
U.S. Navy
Oral Statement............................................... 153
Written Statement............................................ 155
Biography.................................................... 157
Mr. James Lopez, Senior Advisor to the Deputy Secretary, U.S.
Department of Housing and Urban Development
Oral Statement............................................... 158
Written Statement............................................ 160
Biography.................................................... 166
Mr. William Geer, Director of the Center for Western Lands,
Theodore Roosevelt Conservation Partnership
Oral Statement............................................... 166
Written Statement............................................ 169
Biography.................................................... 172
Dr. Judith A. Curry, Chair of the School of Earth and Atmospheric
Sciences, Georgia Institute of Technology
Oral Statement............................................... 172
Written Statement............................................ 174
Biography.................................................... 179
Discussion
The U.S. Navy and Weather Conditions........................... 179
Climate Monitoring Instrumentation............................. 181
Adaptation Challenges and Poor Communities..................... 182
A National Climate Service..................................... 184
The Impacts of Climate Change on Recreational Fishing.......... 186
Adaptation of Animal Species to a Changing Climate............. 187
Combined Factors Affecting Climate............................. 188
Blogging, Scientific Integrity, and Public Information......... 189
An Anecdote on Risk Management................................. 190
Appendix: Answers to Post-Hearing Questions
Dr. Ralph J. Cicerone, President, National Academy of Sciences... 194
Dr. Richard S. Lindzen, Alfred P. Sloan Professor of Meteorology,
Department of Earth Atmospheric and Planetary Science,
Massachusetts Institute of Technology.......................... 198
Dr. Patrick J. Michaels, Senior Fellow in Environmental Studies,
Cato Institute................................................. 200
Dr. Benjamin D. Santer, Atmospheric Scientist, Program for
Climate Model Diagnosis and Intercomparison, Lawrence Livermore
National Laboratory............................................ 203
Dr. Judith A. Curry, Chair of the School of Earth and Atmospheric
Sciences, Georgia Institute of Technology...................... 209
A RATIONAL DISCUSSION OF CLIMATE CHANGE: THE SCIENCE, THE EVIDENCE, THE
RESPONSE
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WEDNESDAY, NOVEMBER 17, 2010
House of Representatives,
Subcommittee on Energy and Environment
Committee on Science and Technology
Washington, DC.
The Subcommittee met, pursuant to call, at 10:38 a.m. In
Room 2325, Rayburn House Office Building, Hon. Brian Baird
[Chairman of the Subcommittee] presiding.
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
hearing charter
COMMITTEE ON SCIENCE AND TECHNOLOGY
SUBCOMMITTEE ON ENERGY AND ENVIRONMENT
U.S. HOUSE OF REPRESENTATIVES
A Rational Discussion of Climate Change:
the Science, the Evidence, the Response
wednesday, november 17th, 2010
10:30 am
2325 rayburn house office building
Purpose
On Wednesday, November 17, 2010 the Subcommittee on Energy and
Environment of the House Committee on Science and Technology will hold
a hearing entitled: ``A Rational Discussion of Climate Change: the
Science, the Evidence, the Response''. The Subcommittee will receive
testimony on the basic science underlying how climate change happens;
the evidence and the current impacts of climate change; and the actions
that diverse sectors are taking today to respond to and prepare for a
changing climate.
Witnesses
Panel 1
Dr. Ralph Cicerone is the President of the National
Academy of Sciences. Dr. Cicerone will explain the basic
science, including the fundamental physics, underlying how
climate change happens. He will also discuss the role of the
National Academy of Sciences in advancing climate science and
informing the public on the issue.
Dr. Heidi Cullen is the CEO and Director of
Communications at Climate Central. Dr. Cullen will discuss the
basic science of climate change, including the fundamental
chemistry, the causes of production of greenhouse gases; and
the expected impacts on the climate.
Dr. Gerald A. Meehl is a Senior Scientist in the
Climate and Global Dynamics Division at the National Center for
Atmospheric Research. Dr. Meehl will discuss the basic physics
underlying how climate change happens and how the physics is
incorporated into the development of the climate models.
Dr. Richard Lindzen is the Alfred P. Sloan Professor
of Meteorology in the Department of Earth, Atmospheric, and
Planetary Sciences at Massachusetts Institute of Technology.
Dr. Lindzen will discuss how greenhouse gas emissions resulting
from human activities will only minimally contribute to
warming. He will also discuss the limitations in the global
climate models and the problems with the positive feedbacks
built into the models.
Panel 2
Dr. Benjamin Santer is an Atmospheric Scientist in
the Program for Climate Model Diagnosis and Intercomparison at
the Lawrence Livermore National Laboratory. Dr. Santer will
discuss the evidence of climate change; how well the science
validates that climate change is happening; and the
computational climate models, including how the various climate
data sets are utilized and analyzed.
Dr. Richard Alley is the Evan Pugh Professor in the
Department of Geosciences and an Associate of the Earth and
Environmental Systems Institute at Pennsylvania State
University. Dr. Alley will describe the effects of climate
change on ice dynamics and explain how changes in levels of
carbon dioxide in the atmosphere have led to a rise in global
temperatures.
Dr. Richard Feely is a Senior Scientist at the
Pacific Marine Environment Laboratory of the National Oceanic
and Atmospheric Administration (NOAA). Dr. Feely will discuss
the current science and understanding of ocean acidification,
the factors that contribute to the acidification process, and
the resulting impacts.
Dr. Patrick Michaels is a Senior Fellow in
Environmental Studies at the Cato Institute. Dr. Michaels will
discuss the rate of greenhouse-related warming; the
Endangerment Finding by the Environmental Protection Agency;
and scientific integrity.
Panel 3
Rear Admiral David Titley is an Oceanographer and
Navigator for the United States Department of the Navy,
Department of Defense. RADM Titley will discuss the impacts of
climate change on U.S. Navy missions and operations, the
national security implications of climate change, and the role
of the U.S. Navy's Task Force Climate Change.
Mr. James Lopez is the Senior Advisor to the Deputy
Secretary at the Department of Housing and Urban Development.
Mr. Lopez will discuss the impacts of climate change on
vulnerable populations and communities; HUD's proposed
Sustainable Communities Initiative; and how the Department is
working to improve the coordination of transportation and
housing investments to ensure more regional and local
sustainable development patterns, more transit-accessible
housing choices, and reduced greenhouse gas emissions.
Mr. William Geer is the Director of the Center for
Western Lands for the Theodore Roosevelt Conservation
Partnership. Mr. Geer will discuss the threat of climate change
to hunting and fishing; its impacts on fish and wildlife; and
how the Theodore Roosevelt Conservation Partnership is
responding to the impacts of climate change.
Dr. Judith Curry is the Chair of the School of Earth
and Atmospheric Sciences at Georgia Institute of Technology.
Dr. Curry will discuss how uncertainty in data and conclusions
is evaluated and communicated. She will also discuss how this
uncertainty should be incorporated into decision-making
efforts.
Background
Human society is shaped by the climate in fundamental ways, and so
for many decades researchers around the world have been working to
understand how humans are affecting the climate, the impacts of these
changes, and how society can mitigate and prepare for these effects.
Since human settlement began, climate has influenced what we wear, the
food that we eat, where we live, and how we build our houses. And
despite our greatest technological advances, climate still affects how
and where we live our lives today, as well as our economy and national
security. Various sectors, from agriculture to transportation, rely on
climate certainty. Climate change has increased uncertainty in many
sectors; therefore, many decisions with significant economic impacts
will have to be made with greater levels of associated risk.
Advancements in climate science may reduce uncertainty in climate
dependent sectors, thus better informing decisions that impact the
quality of our lives.
Climate and Weather
Climate can be defined as the product of several meteorological
elements \1\ in a given region over a period of time. In addition,
spatial elements such as latitude, terrain, altitude, proximity to
water and ocean currents affect the climate. We experience climate on a
daily basis through the weather. The difference between weather and
climate is a measure of time--weather consists of the short-term
(minutes to months) changes in the atmosphere. Weather is often thought
of in terms of temperature, humidity, precipitation, cloudiness,
brightness, visibility, wind, and atmospheric pressure. Weather is what
conditions of the atmosphere are over a short period of time, and
climate is how the atmosphere ``behaves'' over relatively long periods
of time. In most places, weather can change from minute-to-minute,
hour-to-hour, day-to-day, and season-to-season. Climate, however, is
the average of weather over a period of years to decades. Generally,
climate is what you expect, like a very hot summer in the American
Southwest, and weather is what you get, like a hot day with pop-up
thunderstorms.\2\
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\1\ Meteorological elements such as temperature, humidity,
atmospheric pressure, wind, rainfall, and atmospheric particle count.
\2\ See -pages/noaa-n/
climate/climate-weather.html>.
The Science
Climate can be influenced by a variety of factors, including:
changes in solar activity, long-period changes in the Earth's orbit,
natural internal processes of the climate system, and anthropogenic
(i.e. human-induced) increases in atmospheric concentrations of carbon
dioxide (CO2) and other greenhouse gases (GHGs).\3\ As
described above, ``climate'' is the long-term average of a region's
weather patterns, and ``climate change'' is the term used to describe
changes in those patterns. Climate change will not have a uniform
effect on all regions and these differing effects may include changes
to average temperatures (up or down), changes in season length (e.g.
shorter winters), changes in rain and snowfall patterns, and changes in
the frequency of intense storms. The scientific community has made
tremendous advances in understanding the basic physical processes as
well as the primary causes of climate change. And researchers are
developing a strong understanding of the current and potential future
impacts on people and industries.
---------------------------------------------------------------------------
\3\ In addition to long-term climate change, there are shorter term
climate variations. This so-called climate variability can be
represented by periodic or intermittent changes related to El Nino, La
Nina, volcanic eruptions, or other changes in the Earth system.
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Throughout Earth's history, the climate has changed in dramatic
ways. What makes this point in time different from the past is the
human influence on this change and the rate at which this change is
occurring. Volumes of peer-reviewed scientific data show that CO2
concentrations in the atmosphere have increased substantially since
industrialization began. Fossil fuel use has become an increasingly
important part of our lives, and as a result, CO2
concentrations have increased approximately 30% since pre-industrial
times.\4\ And the current level of CO2 in the atmosphere is
the highest in the past 650,000 years.\5\ According to the National
Academies, there is strong scientific consensus that these increases in
CO2 concentrations intensify the greenhouse effect, and this
effect plays a critical role in warming our planet.\6\
---------------------------------------------------------------------------
\4\ See -factsheet.pdf>.
\5\ Michael Hopkin, Greenhouse-Gas Levels Highest for 650,000
Years: Climate Record Highlights Extent of Man-Made Change, Nature
News. Published Online. (24 Nov 2005). doi:10.1038/news051121-14.
\6\ National Research Council, America's Climate Choices: Advancing
the Science of Climate Change (2010).
Greenhouse Effect
Greenhouses work by trapping heat from the sun. The glass panels of
the greenhouse let in light but keep heat from escaping. This causes
the greenhouse to heat up, much like the inside of a car parked in
sunlight. Greenhouse gases in the atmosphere behave much like the glass
panes in a greenhouse. Sunlight enters the Earth's atmosphere, passing
through the blanket of greenhouse gases. As it reaches the surface, the
Earth's land, water, and biosphere absorb the sun's energy. Once
absorbed, this energy is eventually transmitted back into the
atmosphere through physical processes such as heat conduction,
convection, and evaporation. Some of the energy passes back into space,
but much of it remains trapped in the atmosphere by the greenhouse
gases, causing the Earth to heat up.
As a basis for discussion about GHGs and their influence on the
climate, it should be noted that there is a natural, non-anthropogenic
greenhouse effect, which Joseph Fourier discovered more than 150 years
ago. Fourier argued that ``the atmosphere acts like the glass of a
hothouse because it lets through the light rays of the sun but retains
the dark rays from the ground''.\7\ This is a major simplification in
describing the greenhouse effect, but it does provide insight into why
the Earth's surface is considerably warmer than it would be without an
atmosphere.
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\7\ Joseph Fourier, Remarques Generales Sur Les Temperatures Du
Globe Terrestre Et Des Espaces Planetaires, 27 Annales de Chimie et de
Physique p.136-67 (1824). and Joseph Fourier, Memoire Sur Les
Temperatures Du Globe Terrestre Et Des Espaces Planetaires, 7 Memoires
de l'Academie Royale des Sciences p.569-604 (1827).
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Several scientists built on Fourier's greenhouse theory by
recognizing the importance of the selective absorption of some of the
minor constituents of the atmosphere, such as CO2 and water
vapor. Swedish chemist Svante Arrhenius conducted an extensive analysis
of the greenhouse effect.\8\ Arrhenius calculated the temperature
increase caused by the greenhouse effect as a function of the
atmospheric concentration of ``carbonic acid'' \9\, latitude, and
season. The values Arrhenius obtained for the warming of the atmosphere
are very much in agreement with what are now being obtained using
complex climate models. Further research in the 1930s showed that, due
to the more extensive use of fossil fuels, the atmospheric
concentration of carbon dioxide was increasing, and the first
projection of the atmospheric CO2 concentration was made in
the late 1950s.\10\ As these scientific findings were coming to light,
operational data collection programs were initiated for measuring
atmospheric CO2 in Scandinavia, Mauna Loa, Hawaii and at the
South Pole.
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\8\ Svante Arrhenius, On the Influence of Carbonic Acid in the Air
upon the Temperature of the Ground 41 Philosophical Magazine p.237-276
(1896). and Elisabeth T. Crawford, Arrhenius: From Ionic Theory to the
Greenhouse Effect (Science History Publications) (1996).
\9\ Carbonic acid is a byproduct of carbon dioxide when dissolved
in water.
\10\ Roger Revelle and Hans E. Suess, Carbon Dioxide Exchange
Between Atmospheric and Ocean and the Question of an Increase of
Atmospheric CO2 during the Past Decades, 9 Tellus p.18-27
(1957).
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Carbon dioxide (CO2) is a greenhouse gas (GHG) that
traps the sun's radiation within the troposphere, i.e. the lower
atmosphere. It has accumulated along with other man-made greenhouse
gases, such as methane (CH4), chlorofluorocarbons (CFCs),
nitrous oxide (N2O), hydrofluorocarbons (HFCs),
perfluorocarbons (PFCs), and sulfur hexafluoride (SF6). GHGs
are an important part of our atmosphere because they keep Earth from
having an inhospitably cold surface temperature.\11\ That said, if the
greenhouse effect becomes stronger, through increased concentrations of
GHGs and water vapor, it could make the Earth warmer than human
civilization and its surrounding ecosystem has currently adapted to.
Even a small additional warming is predicted to cause significant
issues for humans, plants, and animals.
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\11\ See .
The Scientific Process: Uncertainty, Consensus, and Peer Review
Climate science, like all science, is an iterative process of
collective learning: data are collected; hypotheses are formulated,
tested, and refined; theories are constructed and models are built in
order to synthesize understanding and to generate predictions; and
experiments are conducted to test these hypotheses, theories, and
models. New observations and refined theories are incorporated
throughout this process, and predictions and theories will be further
supported or refuted. Confidence in a theory grows if it is able to
survive this rigorous testing process, if multiple lines of evidence
converge in agreement, and if competing explanations can be ruled out.
The scientific community uses a highly formalized version of peer
review to validate research results and improve our understanding of
the relevance of these results. Through this process, only those
concepts that have been described through well-documented research and
subjected to the scrutiny of other experts in the field become
published papers in science journals and accepted as current scientific
knowledge. Although peer review does not guarantee that any particular
published result is valid, it does provide a high assurance that the
work has been carefully vetted for accuracy by informed experts prior
to publication. The overwhelming majority of peer-reviewed papers about
global climate change acknowledge that human activities are substantial
contributing factors.
Science is based on observations and therefore uncertainty is
inherent to the scientific process. Uncertainties about climate change
will never be completely eliminated by scientific research, but science
can enable decision makers to make informed choices in the face of
risks.\12\
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\12\ National Research Council, America's Climate Choices:
Advancing the Science of Climate Change p.15 (2010).
The Evidence
There are numerous effects that can result from climate change.
Some effects are already being felt today, and some are projected by
scientists to occur in the future. Scientifically documented evidence
of climate change includes:
Sea Level Rise. The global sea level rose about 17 centimeters (6.7
inches) in the last century. The rate in the last decade, however, is
nearly double that of the last century.\13\
---------------------------------------------------------------------------
\13\ J.A. Church and N.J. White, A 20th Century Acceleration in
Global Sea Level Rise, 33 Geophysical Research Letters (2006).
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Global Temperature Rise. The major comprehensive global surface
temperature reconstructions, which use a wide variety of data sources
from satellites to weather stations, show that Earth has warmed since
1880.\14\ Most recorded warming has occurred since the 1970s, with the
twenty warmest years having occurred since 1981 and with all ten of the
warmest years occurring in the past twelve years.\15\ Even though the
2000s witnessed a solar output decline resulting in an unusually deep
solar minimum in 2007-2009, surface temperatures continue to
increase.\16\
---------------------------------------------------------------------------
\14\ See .
\15\ T.C. Peterson et. al., State of the Climate in 2008, 90
Special Supplement to the Bulletin of the American Meteorological
Society p.S17-S18 (2009).
\16\ I. Allison et. al., The Copenhagen Diagnosis: Updating the
World on the Latest Climate Science, (UNSW Climate Change Research
Center, Sydney, Australia) (2009).
---------------------------------------------------------------------------
Warming Oceans. The oceans have absorbed much of the increased
heat, with the top 700 meters (about 2,300 feet) of ocean showing
warming of 0.302 degrees Fahrenheit since 1969.\17\
---------------------------------------------------------------------------
\17\ Levitus et. al., Global Ocean Heat Content 1955-2008 In Light
of Recently Revealed Instrumentation Problems, 36 Geophysical Research
Letters (2009).
---------------------------------------------------------------------------
Shrinking Ice Sheets. The Greenland and Antarctic ice sheets have
decreased in mass. Data from NASA's Gravity Recovery and Climate
Experiment show Greenland lost 150 to 250 cubic kilometers (36 to 60
cubic miles) of ice per year between 2002 and 2006, while Antarctica
lost about 152 cubic kilometers (36 cubic miles) of ice between 2002
and 2005.\18\
---------------------------------------------------------------------------
\18\ See , and -deepsolarminimum.htm>.
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Declining Arctic Sea Ice. Both the extent and thickness of Arctic
sea ice has declined rapidly over the last several decades.\19\
---------------------------------------------------------------------------
\19\ L. Polyak et. al., History of Sea Ice in the Arctic In Past
Climate Variability and Change in the Arctic and at High Latitudes,
U.S. Geological Survey, Climate Change Science Program Synthesis and
Assessment Product 1.2. chapter 7 (2009). and R. Kwok and D.A.
Rothrock, Decline in Arctic sea ice thickness from submarine and ICESAT
records: 1958-2008, 36 Geophysical Research Letters (2009).
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Glacial Retreat. Glaciers are retreating almost everywhere around
the world--including in the Alps, Himalayas, Andes, Rockies, Alaska,
and Africa.\20\
---------------------------------------------------------------------------
\20\ See -balance.html>
and .
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Extreme Weather Events. The number of record high temperature
events in the United States has been increasing, while the number of
record low temperature events has been decreasing, since 1950. The U.S.
has also witnessed increasing numbers of intense rainfall events.\21\
---------------------------------------------------------------------------
\21\ See .
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Ocean Acidification. The carbon dioxide content of the Earth's
oceans has been increasing since 1750, and is now increasing at a rate
of approximately 2 billion tons per year. This has increased ocean
acidity by about 30 percent.\22\
---------------------------------------------------------------------------
\22\ C.L. Sabine et. al., The Oceanic Sink for Anthropogenic
CO2, 305 Science p.367-371 (2004),; Copenhagen. Also see
.
The Response
Scientific research is also invested in developing ways to respond
and adapt to climate change, in addition to developing technologies and
policies that can be used to limit the magnitude of future changes to
the climate. The issues of mitigating, adapting, and responding to the
impacts of climate change are currently being explored through global
collaborative input from a wide range of experts, including physical
scientists, engineers, social scientists, public health officials,
business leaders, economists, and governmental officials. Demand for
information to support climate-related decisions has grown as people,
organizations, and governments have moved ahead with plans and actions
to reduce greenhouse gas emissions and to adapt to the impacts of
climate change. Today, however, the nation lacks comprehensive, robust,
and credible information systems to inform climate choices and evaluate
their effectiveness.
Scientific research plays a role in guiding the nation's response
to climate change by:
projecting the beneficial and adverse effects of
climate changes;
identifying and evaluating the likely or possible
consequences, including unintended consequences, of different
policy options to address climate change;
improving the effectiveness of existing options and
expanding the portfolio of options available for responding to
climate change; and
developing improved decision-making processes.
Chairman Baird. The hearing will now come to order. Our
hearing today is titled: ``A Rational Discussion of Climate
Change: The Science, the Evidence, the Response.'' The purpose
of today's hearing is to conduct an objective review of the
science behind the greenhouse effect, climate change, and
acidification.
My impression has been for some time that many members of
the public and perhaps some in Congress have never had the
opportunity to consider the basic science and, for that matter,
the long history of investigation and data that underlies
scientific understanding of the greenhouse effect, and more
recently, of ocean acidification.
Therefore, today we have three panels of experts with us.
The first will begin today's hearing by setting the foundation
of basic science. They will explain to us the fundamental
physics and chemistry underlying the role of CO2 and
other atmospheric gases in regulating or altering our planet's
temperature and the acidity of the oceans. A bit of a
scientific history lesson will be included as we learn that the
science behind this issue goes back more than 100 years. The
panel will also address questions about how much CO2
has been entering the atmosphere, from what sources, and with
what predicted effects.
From basic scientific findings and methodologies described
by the first panel, we will then consider whether or not the
predicted impacts of CO2 on temperature and ocean
acidity are, in fact, occurring. In other words, we will ask
the question if basic science makes certain predictions about
what should happen if CO2 levels increase in the air
and oceans, what is actually happening in the real world? How
do we know if it is happening or not, and what can we predict
for the future?
The third and final panel will then discuss the impacts
that are being observed and that can be anticipated from
climate change and ocean acidification. Our witnesses will
discuss how we are already responding today and actions we need
to take to prepare for the future. The analysis includes such
matters as national security, social impacts, economic effects,
and health concerns, among others.
I have had the opportunity in preparation for this hearing
to read all of the written testimony. I want to thank the
witnesses for taking time from their busy schedules to prepare
this material and submit it beforehand for the Committee's
analysis. We are also going to post that on the Science
Committee website for those of you who are interested. And I
hope you will be. It is wonderful testimony and very
illuminating.
Before we hear from the witnesses, I want to make just a
few key points. Having taught scientific methodology and basic
statistics and having published, myself, in peer-reviewed
journals, I personally place a paramount importance on
scientific integrity. That is why in the America COMPETES Act,
I authored the provision that insists that institutions seeking
to receive NSF funding have specific course training in
scientific ethics. My understanding is that from academia and
from NSF that this is having a salutary impact, and I am proud
of that impact.
I mention it today because, after all, this is the Science
and Technology Committee. We must, if we are to have any
credibility at all, insist that our witnesses adhere to the
highest standards of integrity, and simultaneously we, Members
of Congress, must hold ourselves and this Committee as an
institution to that standard in our study of the issues and in
our conduct today and in the future.
In the context of climate change and ocean acidification, I
also believe that because our Nation is the biggest historical
producer and second largest current producer of greenhouse
gases, we have a profound moral responsibility to be sure we
get this right. Scripture teaches us to love thy neighbor as
thyself. If our disproportionate impacts on the rest of the
world are harming billions of other people and countless other
species, we are not living up to that scriptural guidance.
Finally, even if one completely rejects the evidence that
will be presented today in reports from the National Academies
of Science and countless other respected bodies, I believe it
still makes good sense to strive for our Nation to be a leader
in clean-energy technology for economic self-interest alone.
Is not the reality of sending hundreds of billions of
dollars abroad, often to countries with values antithetical to
our own, at least a bit troubling for all of us? Is not the
national security risk this creates disconcerting? Are the
known impacts of events such as Exxon Valdez, the Gulf oil
spill, and numerous other events not of sufficient concern to
argue for change, and are not the facts of red-alert days in
our Nation's cities, in which it is unsafe for our children to
breathe, sufficient cause for some degree of consternation and
change?
I personally believe the evidence of climate change and
ocean acidification is compelling and troubling. But even
without that conclusion, I am convinced we must change our
energy policies for reasons of economics, national security,
and environmental and human health. Our Nation has long been a
leader in renewable-energy technology and I believe we must
remain a leader.
This Committee, under the leadership of Chairman Gordon,
and before him Chairman Boehlert, have taken positive steps to
ensure that continues. So too we have been at the forefront of
climate research and should remain a leader there as well. We
must continue this endeavor if we intend to leave our children
and our grandchildren a strong economy and truly an independent
and secure Nation and an environment in which to live, work,
and play.
Finally, as the parent of 5-1/2-year-old twin boys, the
whole effort of my service in Congress and on this committee
has been to ensure that they have a brighter and better future.
If we don't address this issue well and responsibly, I fear we
will fail in that mission and leave them a much less pleasant
future than we have been able to enjoy.
I am excited about today's hearing and these three panels
of witnesses. I thank them for their time. They will help us
better understand the concepts and impacts of climate change.
And I personally thank each of you for being here. And I thank
our outstanding Committee staff for their work in bringing such
superb witnesses.
[The prepared statement of Chairman Baird follows:]
Prepared Statement of Chairman Brian Baird
Good morning and welcome to today's hearing--A Rational Discussion
of Climate Change: the Science, the Evidence, the Response. Several
months ago I suggested to our Science Committee staff that it was time
this Committee held a comprehensive and in depth hearing to really
discuss the science behind climate change and ocean acidification.
I wanted the hearing to fully present the information as
objectively and clearly as possible so that we could all have a sense
of the basic science behind the greenhouse effect and ocean
acidification, and the likely impacts. I also believed it would be
important for our understanding to ensure that scientists with
differing views be invited to testify.
Therefore, today we have three panels of experts with us. The first
panel will begin today's hearing by setting the foundation of basic
science. They will explain to us the basic physics and chemistry
underlying the role of CO2 and other atmospheric gases in
regulating or altering our planet's temperature and the acidity of the
oceans. A bit of scientific history lesson will be included as we learn
that the fundamental science behind this issue goes back more than one
hundred years. This panel will also address questions about how much
CO2 has been entering the atmosphere, from what sources, and
with what predicted effects.
From the basic scientific findings and methodologies described by
the first panel, we will then consider whether or not the predicted
impacts of CO2 on temperature and ocean acidity are, in
fact, occurring. In other words, we will ask the question, ``If basic
science makes certain predictions about what should happen if CO2
levels increase in the air and the oceans, what is actually happening
in the `real world,' how do we know if it is happening or not, and what
can we predict for the future?''
The third and final panel will then discuss the impacts that are
being observed and that can be anticipated from climate change and
ocean acidification. Our witnesses will discuss how we are already
responding today and actions we need to take to prepare for the future.
This analysis includes such matters as national security, social
impacts, economic effects, and health concerns, among others.
I have had the opportunity in preparation for this hearing to read
all of the written testimony. I want to thank the witnesses for taking
time from their busy schedules to prepare this material and submit it
beforehand for the Committee analysis. I hope and trust many of my
colleagues have taken the time as I have to read the testimony from all
the witnesses.
In addition to the written testimony provided by our panelists, I
should note that I have personally gone well beyond to review published
articles by many of those will testify before us today. I have also had
the privilege to participate in various scientific forums domestically
and globally that have examined this issue. Further, I have followed
the matter very closely in the pages of Science magazine, which I
subscribe to personally as a long time member of the American
Association for the Advancement of Science.
Before we hear from the witnesses, I want to make just a few key
points. First, as someone who has taught scientific methodology and
basic statistics, and having published in peer review journals myself,
I place a great importance, paramount importance, on scientific
integrity. That is why I authored the language in the America COMPETES
Act which makes it mandatory for those institutions seeking National
Science Foundation funding to include explicit training in scientific
ethics as a required part of their curriculum. I am proud to say that
initial reports from NSF and the academic community indicate that this
policy is having a substantial and positive effect, as institutions
that formally provided no such explicit training have indeed
incorporated it into their training regimes.
I mention this here because this is, after all, the Science and
Technology Committee. We simply must, if we are to have any credibility
at all, insist that our witnesses adhere to the highest standards of
scientific integrity. Simultaneously, we must hold ourselves and this
Committee as an institution to that standard in our study of the issues
and in our conduct today and in the future.
Recently, some of our colleagues and friends in Congress have
suggested that we needn't worry about this issue of climate change
because God has promised not to let anything happen to us. Speaking
personally, I would be the last to presume that I know God's
intentions. I would, however, suggest that we were given brains for a
reason and the role of this Committee on Science and Technology is to
use those brains to evaluate the information before us as thoroughly
and objectively as possible and take responsible action on that basis.
Perhaps, just perhaps, that is what God might want us to do and that is
how we are supposed to prevent cataclysmic events from occurring.
For those who are convinced, in spite of the evidence, that the
threat of climate change and ocean acidification is not real, we must
ask if the United States, as the biggest historical producer and second
largest current producer of greenhouse gases, does not bear a great and
indeed a moral responsibility to the rest of the world to be sure we
get this right and do not impose adverse consequences on others as the
result of disproportionate impacts from our own actions. Referring to
scripture myself, the Golden Rule, ``love thy neighbor as thyself,''
and other pearls of wisdom seem especially relevant here.
Moreover, even if one completely rejects the evidence that will be
presented today and in reports from the National Academies of Science
and countless other respected bodies, does it not make sense to strive
for our nation to be a leader in clean energy technology for economic
self-interest alone? Is not the reality of sending hundreds of billions
of dollars abroad, often to countries with values antithetical to our
own, at least a bit troubling? Is not the national security risk this
creates disconcerting? Are the known impacts, such as Exxon Valdez, the
recent Gulf Oil spill, and numerous other events not of sufficient
concern to argue for change? Are not the facts of ``red alert'' days in
our nation's cities, days in which it is ``unsafe to breathe'' for our
children, cause for some degree of consternation?
The United States has been a leader in renewable energy technology
and I believe we must remain a leader. Likewise, we have been at the
forefront of climate research and should remain a leader there as well.
Many of the satellite monitoring capabilities, ground observations, and
other tools that enable us to know our local weather and climate
patterns, the health of our ecosystems and oceans, and the quality of
the air we breathe, and that track the many changes occurring on Earth
are available only because of our investments in science programs at
our many federal agencies and academic institutions. We must continue
our investments if we intend to leave our children and grandchildren an
environment in which they too can live, work, and play.
I am excited about this hearing and these three panels of star
witnesses that will help us to better understand these concepts of
climate change and ocean acidification. I want to personally and
sincerely thank you for being here today and I look forward to each of
your testimonies.
Chairman Baird. And with that, I recognize my friend and
colleague, Mr. Inglis, for opening remarks. Sorry. Mr. Hall has
to leave. Are you ready, Mr. Hall? I am told you have to leave
at some point.
Mr. Hall. I am not ready, but I will go.
Chairman Baird. All right. Then, we will recognize you out
of respect for the likely-soon-to-be Chairman of this committee
and a dear friend and a respected member. I recognize Mr. Hall
for as much time as----
Mr. Hall. Thank you, Mr. Chairman. Mr. Chairman, I do thank
you for holding this hearing and I welcome all of the witnesses
testifying on today's three panels. I think we have one witness
for each panel, which is kind of an improvement. Usually we
have one witness for each hearing. But one out of three is
about a fair match, I think. It depends on the quality. But we
are going to have a lot of different approaches to this and
disagreements on it. And I appreciate everybody being here.
Today our country finds itself at a crossroads and we face
a staggering national debt of more than 13 trillion. Almost one
in ten people are out of work, and a bloated Federal
Government. These are serious problems that require solutions
that are defined by restraint and discipline. No longer should
the economy be strained by writing checks we can't afford and a
burdensome regulatory regime brought about by policies that
serve to hamper industry and productivity across our country.
Despite this economic reality, the Administration is
proceeding with regulations to reduce greenhouse gas emissions,
a policy to supplant the cap and trade proposal that failed to
win Congressional approval. The Secretary of Energy testified
before this Committee that such a policy would raise energy
prices for every American. The Energy Information
Administration conducted an analysis of the cap and trade bill
that passed the House in June. It was projected that this
legislation would increase energy prices for consumers anywhere
between 20 percent and 77 percent.
The Administration claims that we must cut our emissions of
carbon dioxide despite the cost, so that we stave off global
climate disruption. They had been calling it global climate
warming. First of all, this new terminology pronounced by the
White House Office of Science and Technology Policy is just
another example of this Administration attempting to rebrand
events to suit their policy objectives. There is no more war.
We don't have war now according to them. Now we have what they
say is overseas contingency operations. There are no more
terrorist acts, despite that guy that murdered those people at
Fort Hood. There is no more terrorist acts. We now have man-
caused disasters, according to the Administration. Let me tell
you something. Changing the name doesn't change what it is. It
is high time the Administration learns how to call a bluebird
blue.
Secondly, this Administration argues--if cutting greenhouse
gas emissions is the policy direction that is justified by the
science, I think this hearing today will demonstrate and could
demonstrate that reasonable people have serious questions about
our knowledge of the state of the science, the evidence, and
what constitutes a proportional response. Furthermore, there
has been an escalating sense of public betrayal by those who
would claim the science justifies these policy choices.
The e-mails posted last November from the Climate Research
Unit at the University of East Anglia in England expose a
dishonest undercurrent within the scientific ethics community.
This incident ignited a renewed public interest in the level of
uncertainty of the scientific pronouncements and an increased
concern that the policy of cap and trade may not achieve its
objective of reducing the impacts of climate change.
While there are only a few scientists involved in this
unethical behavior, it only takes a few bad apples to spoil the
whole bunch. It has created a general atmosphere of doubt with
regards to all scientific endeavors involving the government.
We need only look at how the Administration responded to the
Deepwater Horizon oil spill and see how scientific information
was distorted to promote a specific policy agenda or to change
people's perception of the government's competence.
To add insult to injury, this Administration has neglected
to follow through on promises to issue basic guidelines for
scientific integrity, a failure that has only served to further
erode the public trust.
Given these persistent problems, Mr. Chairman, the public
has even more questions and concerns about how Federal
officials use science to inform policy debates. Sorting
scientific fact from rhetoric is essential and we have a long
way to go on this topic. We must insist on information derived
from objective and transparent scientific practices and we must
hold this Administration accountable for meeting a level of
scientific integrity that the public expects from their
government. Above all, we cannot afford to enact policies that
destroy jobs, hinder economic growth and whittle away our
competitiveness.
I look forward to hearing from our witnesses today and I
yield back my time.
[The prepared statement of Mr. Hall follows:]
Prepared Statement of Representative Ralph M. Hall
Mr. Chairman, thank you for holding this hearing and I welcome all
of the witnesses testifying on today's three panels.
Today, our country finds itself at a crossroads. We face a
staggering national debt of more than $13.7 trillion, almost one in ten
people are out of work, and a bloated federal government. These are
serious problems that require solutions that are defined by restraint
and discipline. No longer should the economy be strained by writing
checks we cannot afford and a burdensome regulatory regime brought
about by policies that serve to hamper industry and productivity across
America.
Despite this economic reality, the Administration is proceeding
with regulations to reduce greenhouse gas emissions, a policy to
supplant the ``cap and trade'' proposal that failed to win
Congressional approval. The Secretary of Energy testified before this
committee that such a policy would raise energy prices for every
American. The Energy Information Administration conducted an analysis
of the ``cap and trade'' bill that passed the House in June. It was
projected that this legislation would increase energy prices for
consumers anywhere between 20% and 77%.
The Administration claims that we must cut our emissions of carbon
dioxide, despite the costs, so that we stave off ``global climate
disruption''. First of all, this new terminology pronounced by the
White House Office of Science and Technology Policy is just another
example of this Administration attempting to rebrand events to suit
their policy objectives. There is no more war, now we have overseas
contingency operations. There are no more terrorist acts; we now have
man-caused disasters. Changing the name does not change what it is.
It's high time the Administration learn, as we say, to call a bluebird
blue.
Secondly, this Administration argues that cutting greenhouse gas
emissions is a policy direction that is justified by the science. I
think this hearing today will demonstrate that reasonable people have
serious questions about our knowledge of the state of the science, the
evidence and what constitutes a proportional response.
Furthermore, there has been an escalating sense of public betrayal
by those who would claim the science justifies these policy choices.
The emails posted last November from the Climate Research Unit at the
University of East Anglia in England exposed a dishonest undercurrent
within the scientific community. This incident ignited a renewed public
interest in the level of uncertainty of the scientific pronouncements
and an increased concern that the policy of ``cap and trade'' may not
achieve its objective of reducing the impacts of climate change.
While there were only a few scientists involved in this unethical
behavior, it only takes a few bad apples to spoil the whole bunch. It
has created a general atmosphere of doubt with regards to all
scientific endeavors involving the government. We need only to look at
how the Administration responded to the Deepwater Horizon oil spill to
see how scientific information was distorted to promote a specific
policy agenda or to change people's perception of the government's
competence. To add insult to injury, this Administration has neglected
to follow through on promises to issue basic guidelines for scientific
integrity, a failure that has only served to further erode the public
trust.
Given these persistent problems, the public has even more questions
and concerns about how federal officials use science to inform policy
debates. Sorting scientific fact from rhetoric is essential, and we
have a long way to go on this topic. We must insist on information
derived from objective and transparent scientific practices. And, we
must hold this Administration accountable for meeting a level of
scientific integrity the public expects from their government.
Above all, we cannot afford to enact policies that destroy jobs,
hinder economic growth and whittle away our competitiveness. I look
forward to hearing from our witnesses today, and I yield back the
remainder of my time.
Chairman Baird. I thank the gentleman. And I am pleased to
recognize my friend and colleague, the Ranking Member of the
Subcommittee, Mr. Inglis.
Mr. Inglis. Thank you, Mr. Chairman. And this is the last
time that you will be chairing a subcommittee, so I want to
thank you for your service. And I hope everybody will join me
in recognizing Mr. Baird for his excellent service here on this
Committee.
Chairman Baird. If I may, I am going to interrupt my friend
because this is the last time he will be in the Ranking chair,
and he has been an outstanding partner to work with and a real
model of a distinguished Member of Congress. Please join me
in--yeah.
Mr. Inglis. There is a cautionary tale there about what
happens when you get friendly with a Democrat. But actually he
is a dear friend and a great guy. Anyhow, I am very excited to
be here, Mr. Chairman, because this is on the record. And, you
know, it is a wonderful thing about Congressional hearings,
they are on the record.
Kim Beazley, who is Australia's Ambassador to the United
States, tells me that when he runs into climate skeptics, he
says to them to make sure to say that very publicly, because I
want our grandchildren to read what you said and what I said.
And so we are on the record and our grandchildren or great-
grandchildren are going to read it.
And so some are here suggesting to those children that here
is the deal. Your child is sick--this is what Tom Friedman gave
me as a great analogy yesterday. Your child is sick. Ninety-
eight doctors say treat him this way. Two say no, this other is
the way to go. I will go with the two. You are taking a big
risk with those kids. Ninety-eight of the doctors say do this
thing. Two say do the other.
So on the record, we are here with important decisions to
be made. And I would also suggest to my free-enterprise
colleagues, especially conservatives here, whether you think it
is all a bunch of hooey that we have talked about in this
Committee, the Chinese don't. And they plan on eating our lunch
in this next century. They plan on innovating around these
problems and selling to us and the rest of the world the
technologies to lead the 21st century. So we may just press the
pause button here for several years, but China is pressing the
fast forward button. And as a result, if we wake up in several
years and we say, gee, this didn't work very well for us, the
two doctors turned out not to be so right. Ninety-eight might
have been the ones to listen to. Then what we will find, is we
are way behind those Chinese folks. Because, you know, if you
have got a certain number of geniuses in the population, if you
are one in a million in China, there are 1,300 of you. And you
know what? They plan on leading the future. So whether you--if
you are a free-enterprise conservative here, just think, if it
is a bunch of hooey, this science is a bunch of hooey, if you
miss the commercial opportunity, you have really missed
something.
And so I think it is great to be here on the record. I
think it is great to see the opportunity that we have got ahead
of us. And since this is sort of a swan song for me and Mr.
Baird, I would encourage scientists that are listening out
there to get ready for the hearings that are coming up in the
next Congress. Those are going to be difficult hearings for
climate scientists, but I would encourage you to welcome those
as fabulous opportunities to teach. Don't come here
defensively. Don't come to this committee defensively. Say I am
glad you called me here today, I am glad you are going to give
me an opportunity to explain the science of climate change.
Because I am here to show you what you spent, say $340 million
a year on the U.S. polar programs. So you spent the money.
Now I am here to tell you what you got out of it. I am
happy to educate you on what the data is. And hopefully we will
have experts like some who are here today, but also--you know,
on a trip from this committee to Antarctica to visit with the
money, the $340 million a year we spent on the polar programs--
that Donald Manahan, who is a professor at USC--the other one.
We claim the real one is in Columbia, South Carolina. But the
other one, you know, the one out on the west coast. That one.
Dr. Manahan is a master teacher. I hope he is one of the
witnesses here, because he is the kind of guy that would
welcome the inquiry and would lead a tutorial for folks that
are skeptics so they could see the science.
Meanwhile, we have got people that make a living and a lot
of money on talk radio and talk TV pronouncing all kinds of
things. They slept at Holiday Inn Express last night and they
are now experts on climate. And those folks substitute their
judgment for the people who have Ph.D.s and who are working
tirelessly to discover the data.
So we have some real choices ahead of us. But I hope in the
future, as we have these hearings, that we realize it is all on
the record and our grandchildren and great grandchildren are
going to get to see. And it could turn out the science is all
wrong. You know, we have had that before. We used to blood-let
people, and I think John Quincy Adams, the Speaker, made the
very helpful suggestion that we move him to the window, and the
poor guy froze to death. Right? He had the stroke over there in
the Lindy Boggs room. So sometimes science turns out to be
wrong.
But other times it turns out to be very right and the key
to scientific endeavor is what we are here to discuss today, is
openness, access to the data, and full challenging of the data.
That is how we advance science.
And I look forward to the hearing, Mr. Chairman. Thank you
for the opportunity.
Chairman Baird. Thank you, Mr. Inglis, for your opening
remarks and for your many years of service in the Congress and
on this committee.
[The prepared statement of Mr. Inglis follows:]
Prepared Statement of Representative Bob Inglis
Good morning, and thank you, Dr. Baird for this hearing and for
your great leadership as Chairman of this Subcommittee.
I'm not a scientist; I just play one in Committee. That's why I'm
so excited about this hearing. After years of intense conversations
about climate policy, energy markets, and technology innovation, we're
closing with a frank discussion about the science of climate change.
This is our chance to ask lingering questions about whether the climate
is changing, what the causes are, and what impacts we can expect to
see. It's a great opportunity to get answers from some of the people
that know best, and to engage people on all sides of the debate in an
endeavor to understand the science.
Right now, I think the most important questions about climate
change are what impacts we can expect to see, and where. Changing
rainfall, temperature patterns, and ocean acidity will have huge
impacts on agriculture, energy infrastructure, ecosystems, and the
marine-based economy. These changes will be very different in the
upstate of South Carolina and in southwest Washington. Those
differences mean big things for farmers, insurance agents, energy
companies, government planners, and anyone else making long term
investments on the ground. I hope to hear from our witnesses how
scientists are working to fill the gaps in our knowledge and give us
the tools we need to cope with a changing climate.
I also hope that the panelists will touch on the Climategate
scandal. While the hacked and leaked emails did not shake the
foundations of scientific agreement on climate change, they exposed a
breach of the public trust. We count on our scientists to live up to
the highest standards of scientific integrity, collaborative science,
and peer review. I'd like to hear about the status of scientific
discourse in the climate community and what improvements need to be
made.
Finally, climate science is so important on capitol hill because of
how climate policy will impact our energy markets. There is an
irrefutable connection between the ways we use energy and the quantity
of greenhouse gases that we emit. There is also an irrefutable
connection between the ways that we use energy and the amount of risk
we expose ourselves to in terms of our public health and our national
security. It's difficult to get Congress to come to agreement on
climate science, but I hope we'll bridge that gap to build a more
prosperous, secure, innovation-driven economy.
I look forward to hearing from our distinguished panelists about
all these issues.
Thank you again, Mr. Chairman, it has been a pleasure serving with
you on this Subcommittee. I would yield to Mr. Hall for his opening
remarks.
[The prepared statement of Mr. Costello follows:]
Prepared Statement of Representative Jerry F. Costello
Good Morning. Thank you, Mr. Chairman, for holding today's hearing
to receive testimony and engage in a discussion of the science,
evidence, and actions different sectors are using to respond to climate
change.
This Committee has met several times in the 111th Congress to
discuss the implications of the changing climate and what solutions are
available to mitigate these impacts. I agree that we must have complete
information from both sides of the debate about how and why our climate
is changing based on science and what steps we can take to address
these changes now and in the future.
First, the majority of scientists now agree the planet is warming,
based on dramatic increases in ocean acidification, rising temperatures
and rainfall, the retreating of glaciers, and the shrinking of ice
sheets. Based on this scientific evidence, these changes will impact
our society and will require responses from public health officials,
economists, scientists, and government officials worldwide. Along with
our international partners, we are taking a variety of approaches to
reduce emissions and improve energy efficiency, but to date no global
response to climate change has been adopted. I would like to hear from
our witnesses how the United States in collaboration with our
international partners can respond to impacts of climate change.
I welcome our panels of witnesses, and I look forward to their
testimony. Thank you again, Mr. Chairman.
Panel I
Chairman Baird. With that, it is my pleasure to introduce
our distinguished first panel of witnesses. And I think Mr.
Inglis' desire to have people who are thoughtful and critical
analysts of the data will be realized with this outstanding
panel. The panel includes Dr. Ralph Cicerone, the President of
the National Academy of Sciences; Dr. Richard Lindzen, the
Alfred P. Sloan professor of meteorology for the Department of
Earth, Atmospheric and Planetary Science, at Massachusetts
Institute of Technology; Dr. Gerald Meehl, Senior Scientist for
the Climate and Global Dynamics Division at the National Center
for Atmospheric Research (NCAR); and Dr. Heidi M. Cullen, the
Chief Executive Officer and Director of Communications for
Climate Central.
Now, those introductions took me about five seconds to read
each. If you read the distinguished biographies of these
extraordinary individuals, it would take you almost five years,
almost, to read. So forgive me for not going into such detail,
but I hope you will check them out on their website. You will
see this is indeed a very competent and capable group of
individuals.
As our witnesses know, we are asking you to summarize an
entire career of research in five brief minutes, after which we
will ask a series of questions. And this is the first panel. We
have two other panels after this. And we will do our level best
to make sure that each panel gets a proportionate amount of
time at our hearing today.
And with that, Dr. Cicerone, please begin.
STATEMENT OF RALPH J. CICERONE, PRESIDENT, NATIONAL ACADEMY OF
SCIENCES
Dr. Cicerone. Thank you, Chairman Baird and Members of the
Subcommittee, for the opportunity to participate in your
hearing today. With your permission, I will present only a
summary of my written testimony.
Scientists have records from geological history of many
past climate changes. For example, there is physical evidence
of past ice ages with warmer intervals in between and of a
100,000-year cycle of ice ages in the past. Volcanoes have also
caused climate changes. For example, a worldwide cooling
followed the June 1991 explosive eruption of Mount Pinatubo in
the Philippines. Our ability to calculate the amount of that
cooling is very high if the volcanic cloud material amounts and
types are measured well. Natural climate changes are likely to
occur in the future.
However, the main reason that we are here today in this
hearing is that humans are also capable of causing Earth's
climate to change. The underlying mechanism is the greenhouse
effect, wherein certain gases and clouds in the atmosphere
surrounding the planet can absorb outgoing planetary infrared
radiation. Each greenhouse gas selectively absorbs infrared
radiation at specific wavelengths, and this signature can be
seen by Earth-orbiting satellites, and was indeed seen as long
ago as 1972.
The natural greenhouse effect has been enhanced by the
increased amounts of greenhouse gases in the air due to human
activity. These increases have occurred in a period of only a
few decades, a very rapid change. The climatic impact of these
greenhouse gases in the atmosphere is influenced also by
changes in atmospheric water vapor and clouds that are
initiated in turn by the warming. As water warms, it evaporates
faster--in fact, disproportionately faster--than the warming.
The evaporation injects water vapor into the air.
While some scientists propose that water vapor increases
due to greenhouse warming might not amplify the original
warming, they are fighting against a fundamental fact of
physics, the steep dependence of vapor pressure of water, which
is the Clausius-Clapeyron equation. The human-caused greenhouse
effect exerts additional leverage on Earth's surface energy
budget. The changes that have been observed in the last three
decades, greenhouse gas concentration increases, temperature
rises on the surface of the Earth, and decreased ice amounts,
can all be seen from space. In fact, that is how many of the
data have been obtained, by looking at the Earth from space.
The specific molecular properties of greenhouse gases have
been measured through laboratory experiments so that the
calculations of the enhanced greenhouse effect due to these
increases in concentrations are very quantitative today. The
equations are the same that we use in designing nuclear weapons
and neutron transport. The impacts of materials which are less
uniformly distributed of various kinds is more difficult to
estimate.
A change in the amount of sunlight reaching the Earth would
also be very important for the planetary energy balance, and
scientists have proposed that changes from the sun are causing
contemporary climate change. But recent evidence from
monitoring the sun itself shows that the amount of solar energy
reaching the Earth has not increased during the last 30 years,
this time of clearly observed climate changes.
Increased concentrations of greenhouse gases have been
observed worldwide for carbon dioxide. The data are of
extremely high quality. Measurements are taken frequently from
many locations on the surface from aircraft satellites and from
dated ice cores that extend back hundreds and thousands of
years; carbon dioxide amounts have increased from approximately
280 parts per million in the late 19th century to around 390
parts per million now, and that the increases are due to human
activities is clear from several lines of evidence.
Fossil fuel burning is causing approximately 85 percent of
the rise, while the release of carbon dioxide from
deforestation, perhaps 15 percent of the total. Methane has
also risen rapidly in the last century, as evidenced from
surface measurements of all kinds and from dated ice cores.
Methane sources for the atmosphere include rice agriculture,
emissions from cattle, the use and transmission of natural gas,
the decay of organic matter placed in landfills, and many human
activities.
Nitrous oxide and other greenhouse gas also has an array of
processes that injects it into the air, mostly traceable to the
increased human usage of synthetic nitrogen fertilizer for
agriculture.
Several classes of chemicals containing fluorine are also
contributing to the enhanced greenhouse effect. And these
increases observed in the concentration in all of these gases
are clearly attributed to human activities.
Now, some observed changes: Surface temperatures, both of
air and of water, show a warming of the Earth in all regions.
The globally averaged warming since 1980 is approximately 1
degree Fahrenheit. Stronger warmings have been measured in the
Arctic region, along with differences season by season and
locality by locality.
Just as one example, the calendar year 2009 was
significantly warmer than the long-term average in the Northern
Hemisphere, but it was cooler than several of the previous
years, while the temperatures in the Southern Hemisphere in
2009 were at a 130-year record high. Further temperature rises
are usually larger over land areas than over oceans.
Chairman Baird. Dr. Cicerone, I am sorry. I will ask you to
summarize briefly if you can. It is always hard to keep it in
the five minutes.
Dr. Cicerone. The heat content of the oceans have increased
roughly in accord with the calculated greenhouse effect and sea
level rise has been increasing more rapidly since the early
nineties than had been observed earlier. And now we are in a
position for measured ice losses over Greenland and Antarctica,
to sum up what is causing the sea level rise. And we got an
answer which is in accord with the measured sea level rise.
This is enormous progress over the last few years. A lot of
continued research is underway. It is needed, for example, for
quantitative calculations and where we go in the future.
I will just close by saying that the National Academy of
Sciences has been active in our national efforts to understand
these issues for over 30 years, and that in all of our reports
we have always said that there is a lot more to learn about
future climate change, but the potential for future changes,
including sudden, abrupt, and large changes is large. Thank
you, Mr. Chairman.
Chairman Baird. Thank you very much.
[The prepared statement of Dr. Cicerone follows:]
Prepared Statement of Ralph J. Cicerone
Chairman Baird and members of the Subcommittee on Energy and
Environment, thank you for the opportunity to participate in your
hearing today. I will address the basic science and physics of climate
change and how climate change happens. In addition, I will describe the
role of the National Academy of Sciences in advancing the science and
informing the public on this topic.
Climate Change in the Past
Earth's climate shapes the conditions for life and it has done so
over geological history as it does now. The kinds of plant and animal
species that can survive are determined or are strongly influenced by
climate as are the locations and kinds of human installations and
settlements such as agricultural areas and routes of transportation on
rivers and oceans.
We have records of many past climate changes from sea-level
changes, from deposits of soils and rocks, and from fossils and other
debris from plant and animal life, big and small, and from chemical
traces such as abundances of elements and their isotopes. There is such
evidence of periodic Ice Ages when glaciers extended over the northern
half of North America, for example, and of intervening warm periods.
The mapping of many of these historical climate changes is imprecise,
that is, we do not know exactly how big were the geographical regions
that experience the changes. Yet, some patterns are clear. For example,
there is a 100,000-year cycle of Ice Ages in the past. These repeated
events were probably triggered by changes in the non-circularity
(eccentricity) of the earth's orbit around the sun. Earth's orbit is
not circular but more like an elipse and just how non-circular the
orbit is, changes slowly. Also, Earth's tilt angle of the access of its
rotation changes periodically and its access of rotation wobbles a bit
over tens of thousands of years. These astronomical changes lead to
small changes in the amount of sunlight received by earth and to the
geographical distribution of sunlight. While no one has yet been able
to predict exactly how Ice Ages are brought on or how earth exits them,
and how quickly, the principles of our understanding are sound.
Volcanoes of certain types have also caused climate changes in the
past. Regions of the earth or even the entire earth can experience
cooling due to volcano injection of reflective matter that floats in
the upper atmosphere (stratosphere). For a year or a few years, such
coolings have been observed, for example, following the June 1991
explosive eruption of Mt. Pinatubo (in the Philippines). Our ability to
calculate the amount of cooling is very high if the volcanic cloud
material amounts and types are measured well.
Earth's Energy Balance and Climate Change Today
These kinds of natural climate changes are likely to occur in the
future although their timing and sizes are not predictable. The main
reason that we are here in this hearing today is that humans are
capable of causing earth's climate change. The underlying mechanism is
the greenhouse effect and the leverage that it exerts is worth
understanding. In fact, many people are not yet aware of how large this
leverage is, or how it arises.
The key scientific principles can be seen by considering the energy
balance of the Earth. The Earth receives energy from the sun and it
sends energy back to space. Every physical body that is warmer than its
surroundings loses energy to its surroundings. Because of the
temperature of the sun, the form of energy that escapes it is mostly
visible light while the temperature of the Earth causes most of the
energy sent away from the Earth to be in the form of infrared
wavelengths. For example, if you have ever done any infrared
photography such as looking at an inhabited house from outside on a
cold winter night, you can see where the hot spots are. Also, some
infrared detector devices for military purposes also operate in
infrared wavelengths. The Earth's energy balance is such that we
receive approximately 237 watts per square meter from the sun as
visible light, averaged over day and night, over the entire surface of
the Earth. A watt is a rate of energy flow of one Joule per second.
Approximately, the same amount of energy leaves the Earth, 237 watts
per square meter, but as infrared waves. One of the earliest scientific
instruments ever orbited around Earth saw the wavelength matter and
distribution of Earth's planetary radiation to space (IRIS instrument),
thus demonstrating the greenhouse effect. Many more recent instruments
and measurements have led to the numbers that I just quoted.
The greenhouse effect is a natural phenomenon that has been active
over the history of the Earth. This fact can be demonstrated by
calculating the temperatures of various planets using the energy-
balance framework and the principles that I just outlined. When we
calculate the temperature of Mars from the amount of sunlight that
reaches it and its reflectivity, we obtain very close to the right
answer as compared to actual measurements. When we calculate the
temperatures of Earth or of Venus using the same framework with
appropriate numbers, we arrive at too low a temperature. We calculate
that the average temperature of Earth is approximately 15 degrees below
zero centigrade which is perhaps 30 degrees centigrade too low and we
calculate a temperature of Venus which is far below what is actually
measured. These errors indicate that something is missing from the
calculation and it is easily demonstrated that inclusion of the natural
greenhouse effect enables one to get much closer to the actual observed
temperature in a revised calculation.
Greenhouse Gases
The key ingredients in the greenhouse effect are greenhouse gases
and clouds which when in the atmosphere surrounding the planet can
absorb outgoing planetary infrared radiation. Mars has a very thin
atmosphere with not much gas at all. Venus has a very thick high-
pressure carbon dioxide atmosphere with many clouds and Earth has the
atmosphere which we have measured and experienced with significance
amounts of natural greenhouse gases, carbon dioxide, water vapor,
methane, and several others. The signature of a greenhouse gas is the
selectivity in how it absorbs infrared radiation at different
wavelengths. This signature is measured in laboratory experiments using
each gas and the signature of individual greenhouse gases can be seen
by Earth-orbiting instruments or even from some other vantage point in
space.
The natural greenhouse effect on Earth has been enhanced or
amplified by the increased amounts of greenhouse gases in the air due
to human activities. The human-enhanced greenhouse effect due to such
increased atmospheric concentrations is now calculated to be 2.7 watts
per square meter, or more than one percent of the incoming solar
energy. And this increase has occurred in a period of a few decades, a
very rapid change. The components of this increase listed in order
starting with the largest is carbon dioxide, methane, nitrous oxide, a
number of fluorine-containing chemicals, and ozone in the lower
atmosphere, etc. When one attempts to calculate the impact on the
climate of the earth, the way that wind motions are forced, and how
temperatures and precipitation amounts change, one must include the
additional forcing due to water-vapor changes caused by the original
greenhouse-gas forcings. The climatic impact of these atmospheric
greenhouse-gas increases is influenced by changes in atmospheric water
vapor and clouds which are initiated by warming. As water warms, it
evaporates faster, disproportionately faster than the amount of
warming. Thus, water vapor is injected into the air. While some
scientists continue to propose that water-vapor changes due to
greenhouse forcing might not amplify the original warming, they are
fighting against this fundamental fact of physics, the dependence of
vapor pressure on temperature (Clausius-Clapeyron Effect).
As I said earlier, it is important to realize that this enhanced
greenhouse effect represents leverage over Earth's energy balance and
Earth's climate. If we look only at humans direct influence on Earth's
energy budget, we find a smaller influence. In particular if we take
all energy, all human energy usage today, all nuclear power, the
burning of all fossil fuels, coal, petroleum, gasoline, natural gas,
the burning of wood, the use of hydroelectric power, of geothermal
power, tidal and solar and wind power, and we average it over the
surface of the Earth, we find a number of 0.025 watts per square meter
or barely 1/100th of the enhanced greenhouse effect. Thus, we see that
the greenhouse effect is exerting leverage of more than a factor of 100
over the impact on Earth's energy budget due only to human energy
usage. This notion and these numbers are very important to understand.
From the viewpoint of atmospheric chemistry, this leverage is not very
surprising considering that chemical catalysis causes minute amounts of
chemicals to be far more important than their small numbers might
suggest. The chemical impact of catalysts can be enhanced by 100,000 to
a million times through the mechanism of catalysis.
Less technically, one can appreciate this leverage by realizing
that these changes on Earth that have been observed in the last three
decades--the greenhouse-gas concentrations, the temperature rises on
the surface of the Earth, the ice amounts on Earth--can all be seen
from space looking back at Earth. In fact, that is how many of the data
have been obtained, by looking at the Earth from space. So these
changes are not small. One of the easiest tasks in foreseeing how
climate change due to human activities will happen, is indeed
evaluating the enhanced greenhouse effect. We know the properties of
greenhouse gases that make them either more or less effective. For
example, because the outgoing planetary radiation occurs mostly in a
well-defined range of wavelengths, an ideal greenhouse gas is one that
absorbs radiation in that same range and does so effectively. An ideal
greenhouse gas is also one which can survive in the atmosphere without
being broken apart and which can be distributed more or less uniformly
on a global scale without being removed. Those properties are largely
chemical and they can be measured through laboratory experiments, and
they have been so measured, so that the calculations of the enhanced
greenhouse effect due to a measured increase in the gas's concentration
are very quantitative and reasonably precise today.
The concept of radiative forcing was first created and employed by
scientists who created the first fluid dynamical models of the
atmosphere. Bob Dickinson and I used the concept to permit a comparison
of the effectiveness of greenhouse gases and their amounts in 1986. In
the early and mid-1980s scientists had become aware that not only are
the increased carbon dioxide amounts capable of influencing Earth's
climate but a number of other chemicals also have this capability
although in lesser amounts. Radiative forcing is a measure of how
strongly substances in the atmosphere affect Earth's energy budget. The
concept has been extended to materials which are less uniformly
distributed such as aerosol particles from biomass burning, from sulfur
pollution, from fossil-fuel burning, smoke particles, and the like. The
impact of those less uniformly distributed substances is more difficult
to estimate because the substance's geographical distributions are not
as well known, so the estimates of such substances on Earth's energy
budget are not as well defined.
Now, obviously, if our concern is over changes to the net energy
balance of the Earth, then a change in the amount of sunlight reaching
the earth is also very important. In fact, any number of scientists
have tried to focus on whether changes from the sun are causing
contemporary climate change. But it is only in the last few years that
we have had enough evidence to be able to say that the changes in
climate that have been observed over the last several decades, are not
due to changes in the output of the sun. It has been known in principle
for a long time that the sun, like other stars, can change its
luminosity over geological timescales but there is no evidence from
other stars or any theory of stellar evolution that suggests that the
sun's output could change by as much of the enhanced greenhouse effect
has changed, that is, over one percent in say 50 years. A more solid
kind of evidence has come from monitoring the sun itself. By stringing
together the records of a series of satellites that have orbited the
earth while observing the incoming sunlight, several scientists have
shown that the amount of sunlight energy reaching the Earth has
oscillated with an approximate 11-year cycle over the last 30 years,
that is, the amount of solar energy reaching the Earth has not
increased during the time of the observed climate changes. So we are
left with the realization that the enhanced greenhouse effect is 15 or
20 times larger than the difference between solar maximum and solar
minimum in the output of the sun. Moreover, the enhanced greenhouse
effect is not oscillating, it is simply continuing to rise, so the
evidence today rules out any significant role for solar changes in
causing the observed climate changes of the last several decades.
I have alluded to increased concentrations of greenhouse gases that
have been observed worldwide that demonstrate human impact. In the case
of carbon dioxide, our data are of extremely high quality; measurements
are taken frequently from many locations on the surface of the Earth,
from aircraft, satellites, and from dated ice cores extending back over
hundreds and thousands of years. The evidence that the increase in
carbon dioxide worldwide amounts from approximately 280 parts per
million in the late 19th century to approximately 390 parts per million
this year is very strong and that the increases due to human activities
is also clear. The lines of evidence that one uses in attributing the
carbon dioxide increase to human activities includes the rate of the
concentration increase compared to the rate of release of carbon
dioxide from fossil-fuel usage, the isotopic content of the carbon
dioxide, the carbon dioxide patterns geographically compared to the
places where carbon dioxide is being released by human activity, by
oceanic amounts, and by known patterns of movement of atmospheric
chemicals. There is a contribution to this increase from human-caused
deforestation. This contribution is approximately 15 percent of the
total while fossil-fuel usage is approximately 85 percent of the total.
The release of carbon dioxide from deforestation is due both to the
direct burning of wood and the decay of exposed soil organic matter.
Methane as a greenhouse gas has also risen rapidly since the late
19th century as evidenced by surface measurements made at many sites
around the world, by satellite measurements and by the amounts of
methane extracted from dated ice cores. The list and sizes of methane
sources for the atmosphere is complicated and it includes rice
agriculture, the domestication of cattle, the use and transmission of
natural gas, the decay of organic matter placed in landfills, and many
other sources. Nitrous oxide, another greenhouse gas, also has an array
of processes that injected it into the atmosphere, mostly traceable to
the increased human usage of synthetic nitrogen fertilizer for
agriculture. Several classes of chemical gases containing fluorine also
contribute to the enhanced greenhouse effect. The chlorofluorocarbons
whose usage was regulated and banned due to the Montreal Protocol and
later amendments to it, still reside in the atmosphere. Several kinds
of replacement chemicals for the chlorofluorocarbons, namely,
hydrochlorofluorocarbons and hydrofluorocarbons are observed to be
increasing in concentration worldwide along with measured increases of
perfluorinated chemicals such as carbon tetrafluoride and
perfluoroethane along with sulfur hexafluoride. The increases observed
in the concentrations of all of these gases are clearly attributed to
human activities. While the enhanced greenhouse effect due to all of
these greenhouse gases has been an inadvertent consequence of human
activities, this force, led by carbon dioxide emissions, continues to
grow with larger consequences for future climate.
Observed Climate Changes
A number of meaningful changes to Earth's climate have been
measured since 1980 or the late 1970s. These include globally averaged
surface temperatures, both of air and of water. Large data sets
covering almost all of the world are available from at least three
climate centers around the world, one from NASA, one from NOAA, and one
from the University of East Anglia. These data sets are generally
similar although they consist of somewhat different entries with more
or less weighting from individual continents and the Arctic and they
employ somewhat different methods to adjust for potential biases such
as the encroachment of urban areas and the urban heat-island effect on
thermometer stations which were at one time far from urban areas. As an
example, the data sets use slightly different time periods of
comparison but they all show a warming of the earth in all regions. The
globally averaged warming since 1980 is approximately one degree F.
Stronger warmings have been measured in the Arctic region with, of
course, differences season-by-season and locality-by-locality. Just as
one example, the calendar year 2009 was significantly warmer than the
long-term average of the Northern Hemisphere but it was cooler than
several of the previous years while the temperatures in the Southern
Hemisphere in 2009 were at an all-time record high. Further,
temperature rises are higher over land areas than over oceans.
The data on the temperatures and heat content of the upper layers
of the ocean are very important as a measure of global climate change
yet these data are more difficult to obtain with the density of
stations that we would desire because the oceans are not as well
monitored as the atmosphere. Nonetheless, in the last several years,
new data sets have materialized which show an upward trend with time
over the last 40 or 50 years with the amount of heat stored in the
upper layers of the ocean rising, roughly in accord with calculations
of the enhanced greenhouse effect.
A climate variable of great importance especially in the longer
term is sea level. Since 1992, sea level has been measured by Earth-
orbiting instruments on satellites which are capable of measuring sea
level nearly worldwide and frequently so that the trend of rising sea
levels has now been measured more accurately and more precisely in more
places than had been possible before 1992. There is now evidence of a
rate of sea-level rise since 1992 which is approximately twice as fast
as the sea-level rise observed from the late 19th century to 1992 with
far more primitive and fewer instruments in coastal environments.
The amounts of ice residing on land formations in Greenland and
Antarctica are now being measured by independent instruments, vertical
ranging devices on Earth-orbiting satellites, as well as instruments
which measure the deviations of the Earth's gravitational field from
that of a perfect sphere and the rate at which those deviations are
changing. In other words, the data from this instrument can be used to
infer the rate of change of ice mass over those continents. Both kinds
of data now show that over the last perhaps seven or eight years, that
is the entire record of the measurements, that the masses of ice lodged
on Greenland and Antarctica are both decreasing with time with a
possibly accelerating rate. When combined with the inferred amount of
ice lost from continental glaciers and the rate at which sea level is
rising due to thermal expansion, due to the increased temperatures, one
can now calculate how fast sea level is rising and find agreement with
the sea-level rise that is actually measured independently. So this
kind of evidence is new and rather compelling.
Many other important measures of climate change are being gathered,
measures of variables which are directly important to human, animal and
plant life, but which are inherently more variable spatially, that is,
geographically and with time such as the rate of flows of various
streams and rivers, the amounts and kinds of cloudiness, the frequency
and duration of droughts and of storms in many locations, and the
length of growing season and the frequency of new high-temperature
settings and of new low-temperature settings. Continued research on
these variables and many others is essential for us to gauge and
predict climate changes that are underway and how effective human
responses might be.
Efforts to predict more detailed evolution of future climate change
begin with mathematical expressions of the laws that govern the motion
of fluids and their temperatures and of ice amounts. These equations
are of the type which cannot be solved with paper and pencil and with
neat mathematical expressions. Instead, they can only be solved by
numerical computations, computations that are becoming more rigorous
and more understood. Other witnesses will describe more of the
actuality and the details of these efforts, but I do want to emphasize
several kinds of inputs to these mathematical models which require
continued scientific effort. One is the specification of the role of
aerosol particles and of clouds in the atmosphere and another is the
need to specify the rate at which fossil-fuel burning will be used
discharging carbon dioxide into the atmosphere, which rate depends on
growing human population, human activities and energy technology.
The National Academy of Sciences has been active in our national
efforts to detect, understand and predict climatic change. Most of our
analyses are conducted through our operating arm, the National Research
Council, which is co-administered by the National Academy of Sciences
and the National Academy of Engineering. And we often obtain help from
our own Institute of Medicine. There are, of course, many other nations
that are active in climate research and are attempting to mitigate
climate change and/or to adapt to it. And some of these nations not
only conduct research but perform their own nationally based
assessments. In addition, there are international bodies performing
analyses of climate change such as the Intergovernmental Panel on
Climate Change which is a creature of the World Meteorological
Organization and of the United Nations Environmental Program.
Our NAS/NRC reports have been issued more frequently and they have
grown in size over the last 30 years with one of the first major
reports being released in the last 1970s followed by another in 1983,
another series in 1991-92, and then a large number in the early part of
this decade. In the past year, we have written and released a series of
reports entitled, America's Climate Choices, in response to a
Congressional request from the House Subcommittee on Commerce, Justice,
Science and Related Agencies under Chairman Mollohan. This series of
reports examined the state of climate science, what we know, and what
we believe we still must learn along with the state of strategies for
climate mitigation and climate adaptation as well as an analysis of how
to communicate with decision makers and the general public. Another
recent report on climate from the National Research Council is on how
to estimate the emissions of greenhouse gases with regard to any
international agreement that might be adopted and on how well we could
determine compliance with any international agreement. On a completely
separate topic, the National Research Council issued a report recently
on what impacts could be expected by stabilizing the atmosphere at
various target levels of greenhouse gas concentrations. We have also
been asked in the last several years, both by Congress and by Federal
agencies, to examine the effectiveness of the United States Climate
Change Science Program under President Bush, both its plans and its
achievements. All of our reports have been clear that there is much to
learn about future climate change and that the potential of future
disruptions is large.
The Congressional Charter under President Lincoln that created the
National Academy of Sciences in 1863, charges us to be responsive to
requests from the Federal Government for analyses of topics involving
science. Our analyses are conducted by leading American experts
occasionally augmented by talent from other countries. Each of our
reports is peer reviewed by participants who did not engage in the
study itself but whose evaluations and analyses are used so as to
suggest revisions or corrections to the early draft versions of our
reports. This method and the high standards which we attempt to employ
assure that our reports will be of value as our government, our
businesses, and our citizens continue to gauge how to respond to the
challenges which we face today and in the future concerning human-
caused climate change.
Biography for Ralph J. Cicerone
Ralph J. Cicerone is President of the National Academy of Sciences
and Chair of the National Research Council. His research in atmospheric
chemistry, climate change and energy has involved him in shaping
science and environmental policy at the highest levels nationally and
internationally.
Dr. Cicerone's research has focused on atmospheric chemistry, the
radiative forcing of climate change due to trace gases, and the sources
of atmospheric methane, nitrous oxide and methyl halide gases. He has
received a number of honorary degrees and awards for his scientific
work. Among the latter, the Franklin Institute recognized his
fundamental contributions to the understanding of greenhouse gases and
ozone depletion with its 1999 Bower Award and Prize for Achievement in
Science. One of the most prestigious American awards in science, the
Bower Award also recognized his public policy leadership in protecting
the global environment. In 2001, he led a National Academy of Sciences
study of the current state of climate change and its impact on the
environment and human health, requested by President Bush. The American
Geophysical Union awarded Dr. Cicerone its James B. Macelwane Award in
1979 for outstanding contributions to geophysics by a young scientist
and its 2002 Roger Revelle Medal for outstanding research contributions
to the understanding of Earth's atmospheric processes, biogeochemical
cycles, and other key elements of the climate system. In 2004, the
World Cultural Council honored him with the Albert Einstein World Award
in Science. Dr. Cicerone is a member of the National Academy of
Sciences, the American Academy of Arts and Sciences, the American
Philosophical Society, the Accademia Nazionale dei Lincei, the Russian
Academy of Sciences, the Korean Academy of Science and Technology, and
Academia Sinica. He has served as president of the American Geophysical
Union, the world's largest society of earth scientists.
Dr. Cicerone was educated at the Massachusetts Institute of
Technology and the University of Illinois at Urbana-Champaign. In his
early career, he was a research scientist and held faculty positions in
electrical and computer engineering at the University of Michigan. The
Ralph J. Cicerone Distinguished University Professorship of Atmospheric
Science was established there in 2007. In 1978 he joined the Scripps
Institution of Oceanography at the University of California, San Diego
as a research chemist. From 1980 to 1989, he was a senior scientist and
director of the Atmospheric Chemistry Division at the National Center
for Atmospheric Research in Boulder, Colorado. In 1989 he joined the
University of California, Irvine, where he was founding chair of the
Department of Earth System Science and the Daniel G. Aldrich Professor
of Earth System Science. As Dean of the School of Physical Sciences
from 1994 to 1998, he recruited outstanding faculty and strengthened
the school's curriculum and outreach programs. Immediately prior to his
election as Academy president, Dr. Cicerone served as Chancellor of UC
Irvine from 1998 to 2005, a period marked by a rapid rise in the
academic capabilities of the campus.
Chairman Baird. Dr. Lindzen.
Dr. Lindzen. Thank you, Mr. Baird.
Chairman Baird. Make sure the mic is on.
STATEMENT OF RICHARD S. LINDZEN, ALFRED P. SLOAN PROFESSOR OF
METEOROLOGY, DEPARTMENT OF EARTH ATMOSPHERIC AND PLANETARY
SCIENCE, MASSACHUSETTS INSTITUTE OF TECHNOLOGY
Dr. Lindzen. Yes. Thank you, Mr. Baird. Thank you,
Committee, for the opportunity to speak here.
As a student, I was told something rather important; that
the primary thing in solving the problem is to have the right
question. And here I am, a little bit concerned about the
guidelines for this meeting.
I think if we are to properly consider our concern over
greenhouse gases, we must separate the basic science upon which
there is great agreement from the specific bases for our
concern. For instance, there is general agreement that climate
is always changing. There is agreement that over the last two
centuries there has been on the order of 3/4 of a degree
Centigrade increase in something called globally averaged
temperature anomaly.
There is no such thing as average temperature for the
Earth. There is a greenhouse effect. Nobody is arguing that.
That CO2 is a greenhouse gas is not argued by anyone
I know. And that CO2 is increasing due to man's
activities is also widely accepted. To be sure, general
agreement hardly guarantees truth, but I am not questioning it
at this stage. But what is commonly forgotten--and that is
crucial to this hearing--is that these facts do not lead to
major climate concern per se. So, for example, if doubling
carbon dioxide alone leads to only about a degree of warming
and if all the increase in globally averaged temperature
anomaly were due to the added greenhouse gases that Dr.
Cicerone described, it would suggest a sensitivity that is even
lower than that.
The only--the case for alarm rests on three rather doubtful
propositions. One is that climate sensitivity to increasing
greenhouse gases is much greater than the above, due to the
alleged dominance of positive feedbacks. The second is the
association of phenomena, such as sea level rise, arctic sea
ice and so on, which depend on many, many factors, of which
globally averaged temperature anomaly is not even the most
important factor. And to use these changes as evidence for
dangerous warming is illogical. This is especially true with
arctic sea ice. The oversimplification--this is the third
item--of climate to a single number globally averaged
temperature anomaly and a single forcing number--let us say a
radiative forcing from CO2--is a gross distortion of
what is really going on.
Now, with respect to climate sensitivity, greenhouse
physics tells us that temperature changes at the surface should
reduce certain change in outward flux of heat, which at the top
of the atmosphere is in the form of radiation. It will in the
absence of feedbacks correspond to a sensitivity of about 1
degree for a doubling of CO2. Now, if you have
positive feedbacks and you go to space and measure the outgoing
flux associated with the temperature perturbation, you should
see less than you would expect without feedbacks. And if you
have negative feedbacks, you should see more.
Now, it turns out that the models, when you ask what they
calculate, calculate what is consistent with positive
feedbacks. If you go to the data, you find the opposite. Most
recently, there has been an attempt to measure these fluxes
from the surface. Now, you have to understand, the flux might
be reasonably constant through the atmosphere, but its process
is different. So at the top of the atmosphere it is radiation.
At the surface it is mostly evaporation.
And there is a problem that has been noted for some years.
Models predict very little change in evaporation as you warm,
compared to observations. And this can be directly translated
into sensitivity. The model's behavior is consistent with 1-1/2
to 4-1/2 degrees for a doubling of CO2. The data
suggests it is closer to half the lowest limit. So there too, I
mean, one has the problem that the observations, when
specifically turned to feedbacks rather than specific
mechanisms, show the opposite. And this isn't surprising.
One speaks of clouds as a kind of peripheral uncertainty.
But they are capable--they involve changes in the radiative
balance that are, you know, more than a factor of 20, larger
than what you get from a doubling of CO2.
Now, parenthetically, we might wonder why models that have
such high sensitivity can simulate past behavior if the past
behavior is consistent with low sensitivity. And the answer is
I think, as Jerry would point out, is aerosols. Now, you might
say there are really aerosols, so they cancel some of the
greenhouse. But if you check, each model uses a different
value. And the aero--because they want to adjust their model to
look right, so it is an adjustable parameter.
And the aerosol community, Schwartz, Roda, Charlson and so
on have published a paper in the last year pointing out the
uncertainties, meaning that if you include arbitrary aerosols
you can get any sensitivity you want. That is hardly
reassuring.
Chairman Baird. Dr. Lindzen, I will ask, if I may----
Dr. Lindzen. Okay.
Chairman Baird. We are about a minute and a half over. I
know it is hard to summarize. But if you can----
Dr. Lindzen. Okay. Let me just put it--let me just point
out that in my full testimony there are examples, further
examples of each of these things. The climate is certainly
worth understanding better, but the basis for grave worries is
poor; certainly poorer than the changes of suggested policies,
though perhaps not so poor as the prospects for suggested
policies to significantly impact climate or even CO2
levels. Thank you.
Chairman Baird. Thank you, Dr. Lindzen.
[The prepared statement of Dr. Lindzen follows:]
Prepared Statement of Richard S. Lindzen
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Biography for Richard S. Lindzen
Professor Lindzen is a dynamical meteorologist with interests in
the broad topics of climate, planetary waves, monsoon meteorology,
planetary atmospheres, and hydrodynamic instability. His research
involves studies of the role of the tropics in mid-latitude weather and
global heat transport, the moisture budget and its role in global
change, the origins of ice ages, seasonal effects in atmospheric
transport, stratospheric waves, and the observational determination of
climate sensitivity. He has made major contributions to the development
of the current theory for the Hadley Circulation, which dominates the
atmospheric transport of heat and momentum from the tropics to higher
latitudes, and has advanced the understanding of the role of small
scale gravity waves in producing the reversal of global temperature
gradients at the mesopause, and provided accepted explanations for
atmospheric tides and the quasi-biennial oscillation of the tropical
stratosphere. He pioneered the study of how ozone photochemistry,
radiative transfer and dynamics interact with each other. He is
currently studying what determines the pole to equator temperature
difference, the nonlinear equilibration of baroclinic instability and
the contribution of such instabilities to global heat transport. He has
also been developing a new approach to air-sea interaction in the
tropics, and is actively involved in parameterizing the role of cumulus
convection in heating and drying the atmosphere and in generating upper
level cirrus clouds. He has developed models for the Earth's climate
with specific concern for the stability of the ice caps, the
sensitivity to increases in CO2, the origin of the 100,000
year cycle in glaciation, and the maintenance of regional variations in
climate. Prof Lindzen is a recipient of the AMS's Meisinger, and
Charney Awards, the AGU's Macelwane Medal, and the Leo Huss Walin
Prize. He is a member of the National Academy of Sciences, and the
Norwegian Academy of Sciences and Letters, and a fellow of the American
Academy of Arts and Sciences, the American Association for the
Advancement of Sciences, the American Geophysical Union and the
American Meteorological Society. He is a corresponding member of the
NAS Committee on Human Rights, and has been a member of the NRC Board
on Atmospheric Sciences and Climate and the Council of the AMS. He has
also been a consultant to the Global Modeling and Simulation Group at
NASA's Goddard Space Flight Center, and a Distinguished Visiting
Scientist at California Institute of Technology's Jet Propulsion
Laboratory. (Ph.D., '64, S.M., '61, A.B., '60, Harvard University)
Chairman Baird. Dr. Meehl.
STATEMENT OF GERALD A. MEEHL, SENIOR SCIENTIST, NATIONAL CENTER
FOR ATMOSPHERIC RESEARCH
Dr. Meehl. Thank you, Chairman Baird, Members of the
Committee, for the opportunity to communicate information
regarding processes involved with climate change, climate
models, extreme weather, and climate events. But first I want
to begin with a personal perspective that I think is worth
stressing. I think that one of the most interesting, exciting,
and challenging science problems--I emphasize the word
``science'' problems--facing the research community today is
the following: If you add greenhouse gases to the atmosphere,
what is the response of the climate system? It is because of
this compelling science problem that I find research in this
area fascinating and a tremendous intellectual challenge, and
it is why I am here today.
So anyway, the idea that additional CO2 and
other greenhouse gases would cause a warming of the climate is
not a new one. The so-called greenhouse effect has been studied
since the late 1800s, and a number of simple calculations
performed over the early 20th century indicated that the
doubling of CO2 in the atmosphere would likely warm
the planet by at least several degrees.
However, a major development in this field of study was the
emergence of numerical models that could be run on computers.
Equations from fluid dynamics, physics, and thermodynamics can
be used to simulate weather, and this had already been
addressed early in the 20th century in a series of arduous
calculations, performed at that time by hand. It was not until
electronic computers came into use in the 1950s that the
equations could be solved in a rapid enough manner to be used
for actual weather forecasts. This new science of numerical
weather prediction became feasible for operational forecasts in
the 1960s and is still in use today.
Using the same principles and many of the same equations,
early climate models in the 1960s were devised that could be
mathematically integrated forward in time, much like numerical
weather forecasts but for much longer into the future. It was
well known that after about a week, due to the chaotic nature
of the atmosphere, the time evolution of individual storms
could not be resolved by climate models. Instead, the climate
simulations attempted to capture the statistics of weather over
months, seasons, years and decades.
Since the climate models look to weather and climate in
this new way, other factors that could change slowly and thus
affect the statistics of weather had to be included. Therefore,
unlike weather predictions where there was only an atmospheric
numerical model, climate models had an atmosphere as well as
confluence of oceans, land surface, sea ice and equations that
accounted for heating and greenhouse gases or cooling from
visible air pollution.
All of these components were linked together in one large
computer program, run on the fastest supercomputers available,
so that as much detail as possible could be included in the
equations. These models account for physical processes and
feedbacks such as those alluded to by Dr. Lindzen. And these
feedbacks involve water vapor, changes in snow and sea ice and
clouds. And, of course, all of these affect how the climate
system responds to changes in greenhouse gases.
Some of the uncertainty to the range of model responses
seen in increasing CO2 arises from uncertainties in
these feedbacks, particularly clouds. However, climate models
with a cooling contribution from negative cloud feedback still
warms significantly on average over the 20th and 21st century
due to the contributions to increased temperatures, not only
from increasing greenhouse gases but also from warming
feedbacks involving increased water vapor, decreased snow, and
sea ice.
Since the end of the 19th century, global average
temperatures have warmed nearly 3-1/2 degrees Fahrenheit. Many
wonder why we should worry about such seemingly small increases
of temperature. However, even small changes in average
temperature produces very large and more noticeable changes in
weather and climate extremes. It stands to reason that in a
warmer climate, there will be more very hot days and fewer very
cold days.
For precipitation, there is also a temperature-related
connection. As more moisture evaporates from the warming
oceans, the warmer atmosphere can hold that increased moisture.
And when that moisture gets caught up in a storm, there is a
greater moisture source for precipitation. Therefore, we
typically see a greater intensity of precipitation in a warmer
climate. That is, we see greater daily rainfall totals, or when
it rains it pours. Exactly these kind of changes have been
documented in the observations; namely, more heat extremes and
pure cold extremes and increases in precipitation and
intensity.
Additionally, the shift to warmer temperatures has also
produced an increase in daily record-high temperatures compared
to daily record-low temperatures over the United States, with
this ratio currently being about 2-to-1.
For example, since January 1, 2000, there have been over
300,000 daily record-high maximum temperatures set and only
about 150,000 daily record-low minimum temperatures set, a
ratio of about 2-to-1. Just this year since January 1, 2010,
there have been over 17,000 daily record highs and about 6,000
daily record lows, a ratio of more than 2-to-1. Thus, as the
average temperatures warm, the probabilities have shifted
towards more unprecedented heat and less unprecedented cold.
To a first order, climate models are able to reproduce
these changes of temperature and precipitation extremes, thus
building credibility for their future projections. Those
projections of future climate change show ever-increasing heat
extremes and reductions in cold extremes, ongoing increases of
precipitation intensity, and a growing ratio of record-setting
heat compared to record-setting cold.
For example, in one model for one future climate change
scenario, the current ratio of about 2-to-1 record highs to
record lows increases to about 20-to-1 by mid-century and about
50-to-1 by late century. However, even in the late 21st
century, when warming average over the United States was about
4 degrees C, or roughly 70 degrees Farenheit in that model,
there are still record-setting daily low temperatures
occurring. Thus, even in a climate that has warmed
significantly in the model, winter still occurs and it does
occasionally get extremely cold in some locations, cold enough
to set a few daily record-low temperatures every year in that
model. However, those few daily record lows occur in the
context of many more daily record-high maximum temperatures.
And this is yet another aspect of a future warmer climate.
Thank you.
Chairman Baird. Thank you, Dr. Meehl.
[The prepared statement of Dr. Meehl follows:]
Prepared Statement of Gerald A. Meehl
Introduction
I thank the Chairman and other Members of the Committee for the
opportunity to communicate to you today information regarding processes
involved with climate change, climate models, and extreme weather and
climate events. My name is Gerald Meehl, Senior Scientist at the
National Center for Atmospheric Research (NCAR) in Boulder, Colorado.
My research interests include tropical climate involving the monsoons
and El Nino Southern Oscillation, climate variability and climate
change. I have authored or co-authored more than 185 peer-reviewed
scientific journal articles and book chapters. I was a lead author on
the U.S. Climate Change Science Program (CCSP) Report 1.1 on
temperature trends in the atmosphere, and was co-coordinator of the
CCSP Report 3.3 on weather and climate extremes in a changing climate.
I have been involved with the Intergovernmental Panel on Climate Change
(IPCC) assessments since the first one that was published in 1990. I
was a Contributing Author on that first assessment and its update in
1992, a Lead Author for the 1995 Assessment, a Coordinating Lead Author
for the 2001 and the 2007 assessments, and I am currently a lead author
for the recently initiated IPCC Fifth Assessment Report (AR5) due to be
completed in 2013. I am chair of the National Academy of Sciences/
National Research Council Climate Research Committee (CRC). I have been
involved with committees of the World Climate Research Program (WCRP)
on Climate Variability and Predictability (CLIVAR), and am currently
co-chair of the WCRP/CLIVAR Working Group on Coupled Models (WGCM).
This committee organized and coordinated the international modeling
groups in performing climate model experiments for assessment in the
AR4, and in the collection and analysis of data from those model
experiments that was made openly available to the international climate
research community. Our committee is currently involved in performing
similar coordination activities for climate change experiments now
being run by about 20 international climate modeling groups to increase
our understanding of climate model performance and to provide insight
into the climate system response to future climate change mitigation
scenarios. As before, these experiments will be made openly available
for analysis by the international climate science community, and will
also be assessed as part of the IPCC AR5.
The greenhouse effect and how increasing greenhouse gases warm the
climate
Since roughly the beginning of the Industrial Revolution in the
second part of the 19th century, human societies have come to rely on
fossil fuels for an energy source. These fossil fuels--coal, oil, and
natural gas--produce greenhouse gases when they are burned. Thus, as
humans have excavated fossil fuels from beneath the surface of the
earth where they have been sequestered for millions of years, those
fuels have been burned for energy and have released forms of carbon
into the air--greenhouse gases such as CO2 and methane. These
greenhouse gases in trace amounts occur naturally in the atmosphere and
effectively trap some heat in the climate system that would otherwise
escape to space. This occurs because molecules with more than two atoms
(e.g. CO2, CH4, H2O) have the well-known property of being able to
absorb and re-emit infrared or heat energy.
Most molecules are transparent to incoming sunlight, and almost all
sunlight that is not reflected by clouds reaches the earth's surface.
That sunlight heats the surface. and heat (infrared radiation) is
emitted upwards. If greenhouse gases were not in the atmosphere, most
of this heat energy would make it out of the system to space, leaving
the earth a much colder and inhospitable place. However, greenhouse
gases intercept some of this heat or infrared energy, absorb it, and
re-radiate some of it upwards where it continues on out to space, and
some of it is re-radiated downwards, thus staying in the system to warm
the planet. Thus, this heat-trapping effect of greenhouse gases makes
the planet habitable for human, plant and animal life.
Greenhouse gases have been present in our atmosphere for millennia.
It has been shown, from air bubbles trapped in ice sheets, that
greenhouse gases such as CO2 have fluctuated naturally over at least
the past 800,000 years with the ice ages. Of course humans were not
present to cause these fluctuations, but, due to well-understood
orbital variations that change the intensity of solar input, the planet
cools and warms naturally over thousands of years producing the ice
ages and inter-glacial periods. We also know that warmer oceans tend to
emit more CO2 to the atmosphere, while cooler oceans absorb CO2. Thus,
as the orbital variations produce differences in the intensity of solar
input to the climate system that contribute to the ice ages, the oceans
warm and cool as the ice ages come and go naturally, and there is an
amplifying effect from CO2 to enhance the warmth between ice ages (i.e.
the warmer oceans emit more CO2 that warms the climate more), while the
opposite occurs during ice ages to contribute to even colder
conditions.
The concept that CO2 and other greenhouse gases, released when
fossil fuels are burned, would cause a warming of the climate is not a
new idea. In 1895 Svante Arrhenius postulated that increasing levels of
greenhouse gases in the air would warm the climate such that a doubling
of CO2 would warm the planet on average by about 5 to 6C (he later
revised this number downward to 1.6C). These numbers, calculated very
simply from early radiative theory, are not that far off from modem
estimates of 2C to 4.5C derived from global climate models and inferred
from observational data. In the late 1930s Guy Callendar suggested that
the burning of fossil fuels should increase greenhouse gases in the
atmosphere, and that these increases should warm the climate. It wasn't
until the late-1950s, when Charles Keeling started to directly measure
the time evolution of CO2 in the atmosphere to show that there was,
indeed, an increasing trend, that the earlier theoretical estimates of
CO2 increase from the burning of fossil fuels had a basis in a
definitive time series measurement.
The concept that equations from fluid dynamics, physics and
thermodynamics could be used to simulate weather was addressed early in
the 20th century when L.F. Richardson attempted to use a set of those
equations to calculate, by hand, a simple weather forecast for a single
location. However, due to the complexity of the equations and
considerable numerical calculations required, it was not until
electronic computers came into use in the 1950s that the equations
could be solved to produce simulations of the weather in a rapid enough
manner to be used for actual weather forecasts. This new science of
numerical weather prediction became feasible for operational forecasts
in the 1960s. and is still in use today to produce weather forecasts.
Using the same principles, and even many of the same equations,
early climate models were devised that could be integrated forward in
time, much like numerical weather forecasts, but for much longer into
the future. It was well-known that after about a week, due to the
chaotic nature of the atmosphere, the time evolution of individual
storms cannot be resolved by climate models. Instead, the climate
simulations attempted to capture the statistics of weather over months,
seasons, years and decades. Since climate models looked at weather and
climate in this new way, other factors that could change slowly and
thus affect the statistics of weather had to be included. Therefore,
equations that took into account the effects of greenhouse gases were
refined. The varying output of the sun could also be included, as well
as the effects of volcanic eruptions in equations that accounted for
how visible air pollution could cause cooling of the climate. Perhaps
most importantly for longer term variations of the statistics of
weather and climate, the slowly varying parts of the climate system had
to be included, namely the oceans and sea ice, as well as land surface
processes. Unlike weather prediction where there was only an
atmospheric numerical model, climate models had an atmosphere (similar
to a numerical weather prediction model), as well as components of
ocean, land surface, sea ice, and sophisticated equations that
accounted for the heating of greenhouse gases or the cooling of visible
air pollution. All of these components were linked together in one
large computer program that had be run on the fastest supercomputers
available so that as much detail in the equations could be included as
possible, balanced by the need to run the models for tens and even
hundreds of years (as opposed to only about a week for numerical
weather prediction models). Thus, most of the physics, processes, and
feedbacks known to be operating in the climate system were included in
even the earliest global climate models that began to be used in the
1960s.
The warming produced by increases of greenhouse gases, along with
the first order feedbacks, were shown to occur in these very early
climate models. This led to the ``Charney Report'' published by the
National Academy of Sciences in 1979, over 20 years ago. That report
noted that the measured increases in CO2 in the atmosphere, when
included in the basic climate models of that time, produced significant
warming on average over the planet, and that, with further increases in
CO2, the climate would continue to warm. Interestingly, this report was
published after over 30 years of the observed climate not warming
(there was warming until the 1940s, and then little warming until the
late 1970s). Thus, based on the physics of climate already known in the
19th century, and the basic understanding of that time of the processes
that could be captured in equations and included in climate models to
study the statistics of climate, future warming was predicted as a
result of ongoing increases of greenhouse gases, even though the
observed climate had not been warming for decades. Since the time the
Charney Report was published in the late 1970s, there has been an
overall average warming trend. It was not until over 20 years later, at
the beginning of the 21st century, that a generation of improved
climate models, along with better observed datasets, was able to show
how the combinations of natural and human factors that influence
climate produced the time evolution of observed temperature change over
the 20th century.
Results from those studies showed that the warming in the early
part of the 20th century was mainly due to natural causes; a hiatus of
warming from the 1940s to the 1970s was mostly due to a balance between
the warming that would have occurred due to the increases of greenhouse
gases, and the cooling from the visible air pollution in part produced
by the burning of fossil fuels; and finally in the 1970s after air
quality was improved, thereby reducing cooling from visible air
pollution, the ongoing increases of greenhouse gases produced a multi-
decadal warming trend over the past 35 years or so. This warming trend
is not uniform in time (i.e. each year is not warmer than the year
before) due to internally generated natural variability of the climate
system. Depending on the start and end points used to calculate ten
year trends, there are some decades when the warming trend is nearly
flat (e.g.1986-1995; 1998-2007) and times when the warming trend for a
given decade is greater than the longer term trend (e.g. 1975-1984;
1988-1997)
Measurements from the ice cores of air bubbles trapped over the
last 800,000 years indicate the CO2 amount in the atmosphere only ever
got about as high as 280 ppm. In just the last 100 years, that CO2
amount has increased to an unprecedented (over the last 800,000 years)
amount of about 380 ppm currently. Since we know CO2 traps heat in the
atmosphere, the increase in CO2 alone would warm the climate somewhat.
But, just as CO2 acts as an amplifier to past ice ages and inter-
glacials, it also produces other amplifying effects in the atmosphere
called ``feedbacks''. The main ones are water vapor feedback and ice
albedo feedback.
As the oceans warm from the effects of increasing human-produced
greenhouse gases, more moisture evaporates and goes into the atmosphere
as water vapor. Water vapor itself is a greenhouse gas, and also
contributes to trapping heat in the atmosphere, thus amplifying the
effects from increasing CO2 and other greenhouse gases. Ice-albedo
feedback involves ice that covers high latitude oceans (``sea ice'') as
well as snow cover over land. As the climate warms, there is less snow
and sea ice during winter. Because snow and sea ice are highly
reflective (``high albedo''), when there are decreases in snow and sea
ice there are more areas with lower reflectivity. The land and ocean
surfaces with lower reflectivity absorb more energy from sunlight in
the non-winter months. That increase in surface heat content then
inhibits snow and ice from forming in the following winter, thus
leaving even more open ocean and snow-free land to absorb even more
heat the next summer, and so on.
Another feedback that is less certain is cloud feedback. That is,
if clouds increase in a warming climate, there would be more sunlight
reflected and that would be a check on warming (a ``negative
feedback''). However if clouds decrease in a warming climate, the cloud
feedback would be positive and would contribute to even more warming.
To first understand how cloud feedback works, and then incorporate
those processes in climate models, there have to be high quality
observations of the three dimensional structure of clouds. However,
this three dimensional structure has traditionally been very difficult
to observe, though a new generation of recent satellites is, for the
first time, providing observations of just that three dimensional
structure. It is hoped that these new data, coupled with improved
representations of clouds in climate models, will be better able to pin
down the sign and magnitude of cloud feedback. However, even in models
that have a negative cloud feedback, the climates of those models still
warm significantly over the 20th and 21st centuries due to
contributions to warming from increasing greenhouse gases and the other
feedbacks, such as those involved with water vapor, snow and sea ice.
Those have been observed to operate on various timescales that can be
measured, such as the seasonal cycle, and then validated in climate
models.
Many climate change impacts will be experienced through changes in
weather and climate extremes
Droughts, floods, hurricanes, record heat and cold extremes affect
human societies, economies and ecosystems in significant ways, from
effects on human health and mortality, to disruptions of agriculture
and economic activity, to impacts on outdoor activities and tourism.
Though there are many types and categories of extremes, I will focus
here on changes in daily temperature and precipitation extremes.
Weather and climate extremes are a naturally occurring part of our
climate system, and thus have always had a disruptive effect on humans
and the natural system. As such there has been a certain degree of
adaptation to such extreme events. These adjustments range from such
mundane things as air conditioning, to insurance programs that cover
losses from extreme events. However, if the naturally occurring aspects
of weather and climate extremes change significantly, so will the
impacts, and thus weather and climate extremes in a changing climate
become of interest for a variety of applications.
A small change in average climate produces a disproportionately large
change in extremes
Since the end of the 19th century, globally averaged temperatures
have warmed about 0.8C or about 1.4F. Projections for the end of the
21st century made with climate models using a variety of scenarios of
future climate change show temperature increases that range from a
couple of degrees Centigrade (about 3.5F) for a low emissions scenario
to over 8C (about 14F) for a high emission scenario by the end of this
century. However, these are seemingly small increases when the day-
night temperature differences at certain locations are often tens of
degrees. Many wonder why we should worry about such seemingly small
increases in temperature.
Of course these small changes in globally averaged temperature do
not reflect the geographic pattern of change where some regions so far
have seen very little warming (e.g. the southeastern part of the U.S.)
to other areas that have already experienced substantial warming of
nearly 10C in some high latitude areas of the Arctic. And these average
changes are reflected by a host of impacts that happen over the long
term that have already affected human societies.
However, even such small changes in average temperature produce
disproportionately large changes in extremes. A good example is
temperature. A weather station with a record long enough to capture
most of the eventualities of weather at that location usually has a
probability of a certain temperature occurring at that location in the
form of the familiar ``bell-shaped curve''. There is the highest
probability of a temperature occurring that is near the long term
average (near the center of the curve), with a much smaller probability
of an extremely hot or cold temperature occurring (out near the right
and left ``tails'' of the curve, respectively). Thus, if there is even
a small warming in the average temperature, all else being equal, the
curve shifts to the right a bit. But this small shift is reflected in a
much higher probability of an extremely hot temperature occurring, and
a much lower probability of an extremely cold temperature happening.
Therefore, seemingly small warming can produce very large and more
noticeable changes in extremes.
The physical processes involved in changes in daily temperature and
precipitation extremes are relatively
straightforward to understand in the observed
system, and can be captured by climate models
There are a couple of relatively simple physical principles that
govern daily extremes of temperature and precipitation. For
temperature, as noted above, a small average warming produces a
disproportionately large increase in hot extremes and a greater
decrease in cold extremes. It stands to reason that in a warmer
climate, there will be more very hot days, and fewer very cold days.
For precipitation, there is a temperature-related connection in that
warmer air can hold more moisture. Thus, as the climate warms, more
moisture evaporates from the warming oceans, the warmer atmosphere can
hold that increased moisture, and when that more moist air gets caught
up in a storm, there is a greater moisture source for precipitation.
Therefore, we typically see a greater intensity of precipitation in a
warmer climate (i.e. greater daily rainfall totals, or ``when it rains
it pours'').
Have we already seen a change in daily temperature and precipitation
extremes over the U.S.?
Since there are thousands of weather stations over the U.S. (and
internationally) that routinely collect daily temperature and rainfall
data, there have been a number of studies that have catalogued an
increase in extreme heat over the past 50 years, a decrease in extreme
cold, and an increase in precipitation intensity. During this time
period, average temperatures have warmed, and, from the physical
principles noted above, we would expect to see just these kinds of
changes in extremes in a warming climate. Such changes have been
documented not only in numerous publications in the peer-reviewed
scientific literature, but also summarized in various assessments of
that literature (e.g. the IPCC AR4, CCSP3.3, and the recent National
Academy of Sciences America's Climate Choices Science Panel Report).
For example, there has been a documented observed trend of
decreases of ``frost days'' (i.e. when the nighttime temperatures go
below freezing), with greater decreases of frost days in the western
U.S. compared to the eastern U.S., also reflecting average warming
patterns over the second half of the 20th century when there has been a
good coverage of stations reporting daily temperature data. The
reduction of extreme cold has had numerous impacts, one being an
increase of pine bark beetles in the western U.S. Extreme cold is
needed to kill the dormant insects during the winter. Due to the
average warming, there has been less extreme cold, and more live to
become active in summer, and they kill even more pine trees. Increases
in extreme warm days have also been documented in observations over the
U.S.
The shift to warmer temperatures has also produced an increase in
daily record high temperatures compared to daily record low
temperatures over the U.S., with this ratio currently being about two
to one. For example, Since January 1, 2000, there have been 311,734
record daily high maximum temperatures set, and only 152,329 daily
record low minimum temperatures, a ratio of about two to one. Since
January 1, 2010, this year, there have been 17,148 daily record highs,
and 6,315 daily record lows, more than a ratio of two to one. Thus, as
the average temperature has warmed, the probabilities have shifted
towards more unprecedented heat, and less unprecedented cold.
For precipitation, the intensity of daily precipitation has also
been observed to increase since the second half of the 20th century,
again when we have a good geographic coverage of daily temperature
data.
Climate models are able to reproduce these observed changes of
temperature and precipitation extremes, and thus build credibility that
we can believe what they tell us about the future. Projections of
future climate change in the models with scenarios of future greenhouse
gas emissions show ever-increasing heat extremes and reductions in cold
extremes, ongoing increases of precipitation intensity, and a growing
ratio of record-setting heat compared to record-setting cold, with, in
one model for one scenario, the current ratio of about two to one
increasing to twenty to one by mid-century, and about fifty to one by
late century. However, even in the late 21st century when warming
averaged over the U.S. is about 4C (or roughly 7F) in the model, there
are still record-setting daily low temperatures occurring. Thus, even
in a climate that has warmed significantly in the model, winter still
occurs, and it does occasionally get extremely cold in some locations,
cold enough to set a few daily record low temperatures every year.
However, those few record daily lows occur in the context of many more
daily record high maximum temperatures that would occur every year.
Summary
The concept that greenhouse gases in the atmosphere make the planet
warm enough to be habitable, and that increasing those greenhouse gases
by the burning of fossil fuels could make the planet even warmer, is
not a new idea and has been studied for over a century. Early attempts
at numerical weather prediction, solving the relevant equations that
describe the physics and thermodynamics of the atmosphere by hand for a
single location in the early 1900s, presaged modem numerical weather
predictions performed routinely by atmospheric models run on
supercomputers. Those atmospheric models attempt to resolve the time
evolution of individual storm systems over the next few days.
Subsequently developed global climate models include atmospheric
components similar to those used in numerical weather prediction, but
add components of the slowly varying parts of the climate system
(ocean, sea ice, and land surface processes). The dynamical coupling of
those components in the models, as in the real world, is relevant to
the statistics of weather over climate timescales of months to years to
decades to centuries. Climate models also have equations that capture
the effects of greenhouse gases and relevant feedbacks in the climate
system that can influence climate. These climate models can reproduce,
to first order, the observed changes in temperature and precipitation
extremes observed over the past 50 years or so. These have included
more heat extremes, fewer cold extremes, greater increases in daily
record high temperatures compared to daily record low temperatures, and
increased precipitation intensity. This lends credibility to the
climate models such that there is likely to be useful information in
their climate projections about future changes of extremes. With
continued increases of greenhouse gases and consequent warming, these
model projections depict a world with ongoing increases in heat
extremes and record heat, reductions in cold extremes and record cold,
and greater precipitation intensity.
Biography for Gerald A. Meehl
Gerald A. Meehl is a Senior Scientist at the National Center for
Atmospheric Research. His research interests include studying the
interactions between El Nino/Southern Oscillation (ENSO) and the
monsoons of Asia; identifying possible effects on global climate of
changing anthropogenic forcings, such as carbon dioxide, as well as
natural forcings, such as solar variability; and quantifying possible
future changes of weather and climate extremes in a warmer climate. He
was contributing author (1990), lead author (1995), and coordinating
lead author (2001, 2007) for the first four Intergovernmental Panel on
Climate Change (IPCC) climate change assessment reports, and is
currently a lead author on the near-term climate change chapter for the
IPCC AR5. He received his Ph.D. in climate dynamics from the University
of Colorado, and was a recipient of the Jule G. Charney Award of the
American Meteorological Society in 2009. Dr. Meehl is an Associate
Editor for the Journal of Climate, a Fellow of the American
Meteorological Society, and a Visiting Senior Fellow at the University
of Hawaii Joint Institute for Marine and Atmospheric Research. He
serves as chair of the National Academy of Sciences/National Research
Council Climate Research Committee, and co-chair of the Community
Climate System Model Climate Change Working Group. Additionally, he is
co-chair of the World Climate Research Programme (WCRP) Working Group
on Coupled Models (WGCM), the group that coordinates international
global climate model experiments addressing anthropogenic climate
change.
Chairman Baird. Dr. Cullen.
STATEMENT OF HEIDI M. CULLEN, CEO AND DIRECTOR OF
COMMUNICATIONS, CLIMATE CENTRAL
Dr. Cullen. Thank you, Chairman Baird and Members of the
Subcommittee, for this opportunity to have a rational
discussion on the science of climate change. I have got a
PowerPoint, which we are going to bring up. And it will
reinforce several of the points that have already been made on
the panel this morning. And I will say that my background is a
little bit different than some of my panel members in the sense
that I spent several years at The Weather Channel as their on-
camera climate expert, and it was a great experience. And it
was really interesting to me because when I got there, most
people just assumed I was a meteorologist. So I got a lot of
questions about what the five-day forecast would be. And while
I love the five-day forecast, it was a really important
opportunity to just help people understand the difference
between climate and weather, the difference between
climatologists and meteorologists, and the difference between
weather forecasts and climate forecasts.
You see the great quote by Mark Twain up there.
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He basically said it all, which is, ``Climate is what we
expect, weather is what we get.'' And I will say basically it
is a lot easier to see the weather. It is a lot easier to see
what we get. Climate is a statistical construct and it is tough
to see it. So our job today is to help you see it and to help
you understand why the forecasts that we make for the end of
this century are something that we can trust.
To start out with, Mother Nature's strongest fingerprint on
our climate system is the seasonal cycle. So here is a climate
forecast for you. Here in DC. It is going to be colder in
January, but then it is going to warm up in July. The climate
forecast. My grandmother could give it to you. It doesn't take
a genius. But it shows you that we have an understanding of our
climate system that allows us to look further into the future.
The other thing that I really hope that our discussion this
morning can help you understand is why our long-term forecast
for the future is something that so many of us on this panel
are deeply concerned about. I made it here by training.
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I worked on Wall Street for a little while and then decided
I was really fascinated by climate. It is a lot like Wall
Street. In many respects it looks kind of like stock market,
ups and downs on various time scales. And I will say that the
tremendous variability of the climate system is fascinating to
me. And this gets to ice core records that you see.
Focus on the last 10,000 years. The top part, which is
pretty flat, that is the last 10,000 years of our climate. And
what is really fascinating is it is relatively stable. So what
drew me into climate science was this question of, to what
extent does climate stability link with human civilization?
These complex human civilizations started at about 10,000 years
ago, right about the same time where our climate began to
become more stable.
So if any of you have read the book ``Collapse'' by Jared
Diamond, you will note that civilizations have failed over time
due to the inability to look out on long enough time scales and
to be adaptive to our environment.
Now, my next slide is more or less to just highlight the
fact that, gosh, we have been studying this problem for an
incredibly long time.
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The gentleman in the oil painting is Svante Arrhenius. He
got the Nobel prize in chemistry in 1903 for doing the back-of-
the-envelope calculation that Dr. Meehl spoke about, which is
that if we doubled CO2 in our atmosphere, our planet
would warm roughly eight degrees Farenheit. Where Arrhenius
made his mistake was that he was around at the turn of the
century in the 1800s, and he basically assumed that we would
continue to emit fossil fuels at the 1895 rate, so it would
take 3,000 years to double. And he was wrong there.
But that is where Bert Bolin came in. Bert Bolin actually
calls for the creation of the IPCC. And he did his own back-of-
the-envelope calculation which suggested that CO2
would increase by about 30 percent by the year 2000. That
turned out to be very true.
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Charles David Keeling, another giant in the field of
climate science, basically figured out how to measure this
invisible greenhouse gas we call carbon dioxide. We wouldn't
need to have this panel if we could see carbon dioxide, because
it is everywhere. By burning fossil fuels and through
deforestation we emit it. But he figured out a way to create
and build a machine that was like an atmospheric Breathalyzer
that could measure CO2 in the atmosphere. And he
showed, just as Bert Bolin calculated, that we have increased
our CO2 in the atmosphere by about 36 percent now.
We are at 390 parts per million. I know that that does not
sound like a lot. But because of the special chemical structure
of carbon dioxide, unlike nitrogen and oxygen, which there is
so much more of in our atmosphere--they have just two atoms--
CO2 has three. And that allows it to absorb
tremendous amounts of long-wave radiation and be a great
absorber of heat. And that is why our planet is essentially
warming up.
The other thing that Keeling was able to do was to
chemically fingerprint the CO2 so that we knew that
it was coming from us. Carbon comes in three different flavors.
You call them isotopes.
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Fossil fuels, when they give off CO2 from
burning, they have essentially no C14 because they are ancient.
So what Keeling was able to do is just say that roughly one out
of every four carbon dioxide molecules in our atmosphere today
was put there by us. It is our human fingerprint on the climate
system.
As Jerry said, we are increasing the overall temperature of
our climate about 1.4 degrees Farenheit over the past century.
How does that make its way into our weather? My experience at
The Weather Channel made it very clear that we can see our
weather, we experience our weather, we know what that means.
But how is climate change impacting our weather?
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Essentially, Mark Twain's quote can now be rewritten, which
is to say that climate is what we expect and weather is what it
gets us. So we can expect to see more extreme events. And if
you talk to, you know, Warren Buffet or anyone who deals with
insurance, they will tell you that if we don't take climate
change into account, we are making very, very costly mistakes.
We insure very, very high amounts of weather-related
disasters each year. This is a picture from the national flood
of 2010. It was considered a 1 in 1,000 year event. That
probability is expected to increase more so with each passing
year if we continue to emit greenhouse gases. Business as
usual.
And just to summarize. I am a scientist by training and I
have to say my time at The Weather Channel really--it just awed
me the way our country could rally around a weather forecast.
Whether it was sand-bagging in advance of the Red River floods
or evacuating in advance of Hurricane Gustav, we know what to
do with the weather forecast. I mean, it is really impressive.
And the thing is how do we figure out how to respond similarly
to a climate forecast. Weather forecast is all defense. I mean,
we get the information, we have got to figure out what to do.
With the climate forecast, the one difference is that we have
the opportunity to change it because it is just one potential
future. So essentially when we think about the future, we are
talking about an increase of 10 degrees Farenheit by the end of
the century, three feet of sea level rise, a radically
different climate.
And the question is, if climate change is this ultimate
procrastination problem, we are in a race essentially to
understand our climate forecasts and just get to the point
where we can act on them. And I would just say that as a
scientist, if we don't do that, that would just simply be
irrational.
Chairman Baird. Thank you, Dr. Cullen.
[The prepared statement of Dr. Cullen follows:]
Prepared Statement of Heidi M. Cullen
Chairman Baird and Members of the Subcommittee, thank you for this
opportunity to engage in a rational discussion of the science of
climate change. My testimony will focus on the basic science and
physics of climate change, the causes and production of anthropogenic
greenhouse gases and the expected impacts on the climate.
Introduction
I am a climate scientist by training, but I have spent the last
several years as a climate science educator--producing reports for
outlets like PBS NewsHour and The Weather Channel. When I first started
at The Weather Channel in 2003 people assumed that if I worked at a 24/
7 weather network, I must be a meteorologist. The question I was asked
most often was ``What's the forecast?'' I was always happy to provide
the local weather forecast. But these experiences made me realize that
many people do not truly understand the difference between climate and
weather, between climatologists and meteorologists. Here's a rough
answer: climatologists pick up where meteorologists leave off. We focus
on timescales beyond the memory of the atmosphere, which is only about
one week. Climatologists look at patterns that range from months to
hundreds, thousands, and even millions of years. The single most
important and obvious example of climate is the seasonal cycle,
otherwise known as the four seasons. Summer, the result of the Earth
being tilted closer to the sun, is warmer. And winter, the result of
the Earth being tilted away from the sun, is colder. The forecast
follows the physics. Which is why, if in January, I issued a forecast
that said it would be significantly warmer in six months, you might not
think I was a genius, but you'd believe it.
There are countless others patterns on our planet that influence
the weather. Take El Nino, for example. El Nino can bring drought to
northern Australia, Indonesia, the Philippines, southeastern Africa and
northern Brazil. Heavier rainfall is often seen along coastal Ecuador,
northwestern Peru, southern Brazil, central Argentina, and equatorial
eastern Africa. There are many ways in which climate can work itself
into the weather.
Meteorologists focus on the atmosphere, whereas climatologists
focus on everything that influences the atmosphere. The atmosphere may
be where the weather lives, but it speaks to the ocean, the land, and
sea ice on a regular basis. The hope is that if scientists can untangle
all the messy relationships at work within our climate system, we
should be better able to keep people out of harm's way. The further we
can extend our forecasts, the longer out in time a society can see, the
better prepared we'll be for what's in the pipeline.
And this is where global warming enters the equation. If the four
seasons are Mother Nature's most powerful signature within the climate
system, then global warming, the term that refers to Earth's increasing
temperature due to a build-up of greenhouse gases in the atmosphere, is
humanity's most powerful signature.
The Basic Science and Physics of Climate Change
We tend to think of man-made global warming as a purely modern
concept, something that has come into vogue in the last 20 or so years,
but in reality this idea is more than 100 years old. The notion that
the global climate could be affected by human activities was first put
forth by Svante Arrhenius in 1895, who based his proposal on his
prediction that emissions of carbon dioxide from the burning of fossil
fuels (i.e., coal, petroleum, and natural gas) and other combustion
processes would alter atmospheric composition in ways that would lead
to global warming. Arrhenius calculated the temperature increase to be
expected from a doubling of CO2 in the atmosphere--a rise of
about 8+F.
More than a century later, the estimates from state-of-the-art
climate models doing the same calculations to determine the increase in
temperature due to a doubling of the CO2 concentration show
that the calculation by Arrhenius was in the right ballpark. The Fourth
Assessment Report of the Intergovernmental Panel on Climate Change
(IPCC) synthesized the results from 18 different climate models used by
groups around the world to estimate the climate sensitivity and its
uncertainty. They estimated that a CO2 doubling would lead
to an increase in global average temperature of about 5.4+F with an
uncertainty spanning the range from about 3.6+F to 8.1+F. It's pretty
amazing that Arrhenius, doing his calculations by hand and with very
little data, came so close to the much more detailed calculations that
can be done today.
In the following section, I aim to provide a brief history of
climate change that will explain the basic physics and chemistry of
global warming and important climate discoveries that serve as the
groundwork of our current scientific understanding of this life-
threatening issue.
- The discovery of the greenhouse effect
The French mathematician and physicist Joseph Fourier in 1824
helped discover the greenhouse effect. Specifically, Fourier was
looking to use the principles of physics to understand what sets the
average temperature of Earth. Fourier was interested in understanding
some basic principles about the flow of heat around the planet. It made
perfect sense that the sun's rays warmed the surface of the Earth, but
this left a nagging question: when light from the sun reaches the
surface of the Earth and heats it up, why doesn't the Earth keep
warming up until it's as hot as the sun? Why is the Earth's temperature
set at roughly 59+F--the average temperature at the Earth's surface?
Fourier reasoned that there must be some type of balance between
what the sun sends in and what the Earth sends back out, so he coined
the term planetary energy balance, which is simply a fancy way of
saying that there is a balance between energy coming in from the sun
and going back out to outer space. If the Earth continually receives
heat from the sun yet always hovers around an average temperature of
59+F, then the Earth must be sending an equal amount of heat back to
space. Fourier suggested that the Earth's surface must emit invisible
infrared radiation that carries the extra heat back into space.
Infrared radiation (IR), like sunlight, is a form of light. But it's a
wavelength that our eyes can't see.
It was a great idea, but when he actually tried to calculate the
planet's temperature using this effect, he got a temperature well below
freezing. So, he knew he must be missing something. To arrive at 59+F,
the Earth's average temperature, Fourier realized that he needed the
atmosphere to pick up the slack. And in the process, he discovered a
phenomenon he called the greenhouse effect. The greenhouse effect is a
process whereby the gases in the Earth's atmosphere trap certain
wavelengths of sunlight, not allowing them to escape back out to space.
Like the glass in a greenhouse, these greenhouse gases let sunlight
through on their way in from space, but intercept infrared light on
their way back out.
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In 1849, an Irish scientist named John Tyndall was able to build on
this idea after he became obsessed with the glaciers he was climbing
while visiting the Alps on vacation. Like so many other scientists at
the time, Tyndall wanted to understand how these massive sheets of ice
formed and grew. He brought his personal observations of glaciers into
the laboratory with him in 1859, when at the age of 39, he began a
series of groundbreaking experiments.
Tyndall was intrigued by the concept of a thermostat. We know them
today as devices that regulate the temperature of a room by heating or
cooling it. So Tyndall devised an experiment that tested whether the
Earth's atmosphere might act like a thermostat, helping to control the
planet's temperature. Tyndall reasoned that it might help explain how
ice ages had blanketed parts of the Earth in the past.
For his experiment, Tyndall built a device, called a
spectrophotometer, which he used to measure the amount of radiated heat
(like the heat radiated from a stove) that gases like water vapor,
carbon dioxide, or ozone could absorb. His experiment showed that
different gases in the atmosphere had different abilities to absorb and
transmit heat. While some of the gases in the atmosphere--oxygen,
nitrogen and hydrogen--were essentially transparent to both sunlight
and IR, other gases were in fact opaque, in that they actually absorbed
the IR, as if they were bricks in an oven. Those gases include
CO2, but also methane, nitrous oxide and even water vapor.
These ``greenhouse gases'' are very good at absorbing infrared light.
They spread heat back to the land and the oceans. They let sunlight
through on its way in from space, but intercept infrared light on its
way back out. Tyndall knew he was on to something. The fact that
certain gases in the atmosphere could absorb infrared radiation had the
makings of a very clever natural thermostat, just as he suspected. His
top three thermostat picks were water vapor, without which he said the
Earth's surface would be ``held fast in the iron grip of frost'',
methane, ozone, and of course, carbon dioxide. Bingo, a natural
thermostat right inside our atmosphere.
Tyndall's experiments proved that Fourier's greenhouse effect was
indeed real. His experiment proved that nitrogen (78%) and oxygen
(21%), the two main gases in the atmosphere, are not greenhouse gases
because these molecules only have two atoms, so they cannot absorb or
radiate energy at infrared wavelengths. However, water vapor, methane
and carbon dioxide, which each have three or more atoms, are excellent
at trapping infrared radiation. They absorb 95% of the long-wave or
infrared radiation emitted from the surface. So, even though there are
only trace amounts of CO2 in the atmosphere, a little goes a
long way to making it really tough for all the heat to escape back into
space. In other words, greenhouse gases in the atmosphere act as a
secondary source of heat in addition to the sun. And it's the
greenhouse gases that provide the additional warming that Fourier
needed to explain that average temperature of 59+F.
Thanks to Tyndall it is now accepted that visible light from the
sun passes through the Earth's atmosphere without being blocked by
CO2. Only about 50% of incoming solar energy reaches the
Earth's surface, with about 30% being reflected by clouds and the
Earth's surface (especially in icy regions), and about 15% absorbed by
water vapor. The sunlight that makes it to the Earth's surface is
absorbed and re-emitted at a longer wavelength known as infrared
radiation that we cannot see, like heat from an oven. Carbon dioxide
(and other heat-trapping gases such as methane and water vapor) absorbs
the infrared radiation and warms the air, which also warms the land and
water below it. More carbon dioxide translates to more warming. And
this is where the concept of a natural thermostat becomes very
powerful--mess with the amount of CO2 in the atmosphere and
you're resetting the thermostat of the planet.
- The discovery of global warming
Svante Arrhenius (1859-1927), a Swedish physicist and chemist,
began his research on global warming by trying to understand the cause
of ice ages. He took Tyndall's thermostat mechanism and explored
whether the amount of CO2 in the atmosphere could raise or
lower the Earth's temperature.
We refer to events or processes that result in changes to the
climate as forcings. A volcano eruption is an example of a natural
forcing. A forcing can often result in an amplification (positive) or a
reduction (negative) in the amount of change and often comes hand in
hand with something known as a feedback--a situation where some effect
causes more of itself. A negative feedback tends to reduce or stabilize
a process, while a positive feedback tends to grow or magnify it.
Arrhenius believed some type of positive feedback mechanism was
responsible for plunging the planet into an ice age. For example, a
drop in carbon dioxide would lead to a drop in temperature creating
more snow and ice. When snow and ice cover a region, such as the Arctic
or Antarctica, their white, light-reflecting surface tends to bounce
sunlight back out to space, helping to further reduce temperature. If
snow and ice covered regions expanded over more of North America and
Europe, the climate would further cool while also leading to growing
ice sheets.
Arrhenius thought his theory was pretty solid, but he wanted to
prove it mathematically. So he set about doing a series of grueling
calculations that attempted to estimate the temperature response of
changing levels of carbon dioxide in the atmosphere. It was a classic
`back of the envelope' calculation, but he was confident enough that he
published the work in 1896 for his colleagues to read. The end result
of all that work was one simple number: 8+F. That number represented
roughly how much Arrhenius thought the Earth's average temperature
would drop if the amount of CO2 in the atmosphere fell by
half.
But back in the time of Arrhenius, global warming impacts were
mainly left to future investigation--at the time, the majority of
scientists still needed to be convinced that the concentration of
CO2 in the atmosphere could vary, even over very long
timescales, and that this could affect the climate. Scientists at the
time were focused more on trying to understand the gradual shifts that
took place over periods a thousand times longer than Arrhenius'
estimate, those that accounted for alternating ice ages and warm
periods, and in distant times (more than 65 million years ago), the
presence of dinosaurs. They couldn't even begin to wrap their minds
around climate change on a human time scale, like decades or centuries.
Nobody thought there was any reason to worry about Arrhenius's
hypothetical future warming that he suggested would be caused by humans
and their fossil fuel burning. It was an idea that most experts at the
time universally dismissed. Simply put, most scientists of the era
believed that humanity was too small and insignificant to influence the
climate.
- the chemical fingerprint of human activity
Fast-forward to the mid-1950's and enter Charles David Keeling, a
brilliant and passionate scientist who was just beginning his research
career at Cal Tech. Keeling had become obsessed with carbon dioxide and
wanted to understand what processes affected fluctuations in the amount
of CO2 in the atmosphere. Answering a question like that
literally required an instrument that didn't exist, the equivalent of
an ultra-accurate `atmospheric breathalyzer'. So Keeling built his own
instrument and then spent months tinkering with it until it was as
close to perfect as he could get at measuring the concentration in
canisters with a range of values of known concentration. Keeling tried
his instrument out by measuring CO2 concentrations in
various locations around California and then comparing these samples in
the lab against calibration gases. He began to notice that the samples
he took in very pristine locations (i.e., spots where air came in off
the Pacific Ocean) all yielded the same number. He suspected that he
had identified the baseline concentration of CO2 in the
atmosphere; a clear signal that wasn't being contaminated by emissions
from factories or farms or uptake by forests and crops. With this
instrument, formally called a gas chromatograph, Keeling headed to the
Scripps Institution of Oceanography to begin what is perhaps the single
most important scientific contribution to the discovery of global
warming. Keeling was on a mission to find out, once and for all, if
CO2 levels in the atmosphere were increasing. He would spend
the next 50 years carefully tracking CO2 and building, data
point by data point, the finest instrumental record of the CO2
concentration in the atmosphere, generating a time history that is now
known to scientists simply as the Keeling Curve.
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The Keeling Curve refers to a monthly record of atmospheric carbon
dioxide levels that begins in 1958 and continues to today. The
instrument Keeling built, the gas chromatograph, works by passing
infrared light through a sample of air and measuring the amount of
infrared light absorbed by the air. Because carbon dioxide is a
greenhouse gas, Keeling knew that the more infrared light absorbed by
the air, the higher the concentration of CO2 in the air.
Because CO2 is found in very small concentrations, the gas
chromatograph doesn't measure in terms of per cent, which means out of
a hundred, but in terms of parts per million (ppm). What he found was
both disturbing and fascinating. Keeling, using his Mauna Loa
measurements, could see that with each passing year CO2
levels were steadily moving upward. In 2010, more than fifty years
after Keeling began his observations, the concentration at Mauna Loa is
390 ppm. Keeling's measurements thus provided solid evidence that the
atmospheric CO2 concentration was increasing. If anything
proved Arrhenius was on to something, it was these data. Keeling's
record was the icing on the cake and he rightly stands with Fourier,
Tyndall, and Arrhenius as one of the giants of climate science. He
helped prove the importance of the greenhouse effect and the reality of
global warming. He provided the data upon which the groundbreaking
theories of Tyndall and Arrhenius firmly rest. As is the case in
research science, Keeling's painstaking measurements have been verified
and supplemented by many others. Measurements at about 100 other sites
have confirmed the long-term trend shown by the Keeling Curve.
Keeling established that carbon dioxide was rising in the
atmosphere. The next step was to find the smoking gun, and see what or
who was causing the increase. In order to put Arrhenius's theory to
rest once and for all, scientists were looking to identify the source
of all that additional carbon dioxide. And they came up with some very
clever ways to identify this smoking gun.
Just as we come into this world with our own unique set of
fingerprints, so too does carbon. Carbon enters the atmosphere from a
lot of different places, places that stamp each molecule of carbon
dioxide and send it off into the atmosphere with a unique fingerprint.
Volcanoes emit CO2 into the atmosphere when they erupt, the
soil and oceans release CO2 into the atmosphere, and plants
and trees give off carbon dioxide when they are cut or burned. Burning
coal, oil and natural gas are all sources that release carbon into the
atmosphere to forms carbon dioxide. The average person, in fact,
breathes out about two pounds of carbon dioxide every day. When you
have the right tools, distinguishing where an individual molecule of
CO2 comes from is not that hard. As with many other
important advances in the fields of climate and weather, this
fingerprint device was an outgrowth of military activity.
Carbon, like virtually all of the chemical elements, come in
different varieties known as isotopes, distinguished by the number of
neutrons in their atomic cores. Carbon dioxide can be made from all of
the isotopes of carbon--but not all sources of CO2 have the
same types of carbon atoms in them. In addition to carbon-14, there is
carbon-12, which is the most common form of carbon, as well as carbon-
13, which makes up only about 1 in every 100 carbon atoms. Carbon-14,
the radioactive one, is even more rare, with only one carbon-14 isotope
for every trillion carbon atoms in the atmosphere. Scientists can use
these isotopes to fingerprint the origin of the carbon. You can
literally trace where the CO2 in the atmosphere originated
by measuring the amount of different carbon isotopes. It's like a
tracing a bullet back to the gun from which it was shot.
All living organisms are built out of carbon atoms. Coal, oil and
natural gas are ancient. In fact, they are called `fossil fuels'
because coal, oil and natural gas come from plants and marine organisms
that lived roughly 200-300 million years ago. Fossil fuels such as
coal, oil and natural gas, for example, have no carbon-14, and neither
does the CO2 that comes from burning them. A small fraction
of the CO2 molecules that enter the atmosphere through
natural means such as the decay of plants, on the other hand, does
contain carbon-14. Because they have extra neutrons, atoms of carbon-14
are more massive than atoms of carbon-12, and so are the CO2
molecules they are made of. Instruments called mass spectrometers
measure that difference. Based on how much of the heavier CO2
they measure in samples of atmosphere, scientists calculate that about
a quarter of the CO2 present today must come from fossil
fuels. From the perspective of a molecule of carbon dioxide, that means
roughly one out of every four CO2 molecules in the
atmosphere today, was put there by us. That conclusion is confirmed by
the fact that this fraction amounts to most of the growth in CO2
over the last 250 years, when fossil-fuel burning has really taken off.
It is this increase in CO2 concentrations that is primarily
responsible for the increase in global average temperatures over the
past century, and especially in recent decades. So while it's true that
most of the carbon dioxide in the atmosphere today comes from natural
sources, most of the additional CO2 that's been placed in
the atmosphere over the last 250 years comes from us.
- the causes and production of anthropogenic greenhouse gases
From 1000 A.D. to about 1750 AD, carbon dioxide levels in the
atmosphere hovered between 275 and 285 parts per million (ppm), and
then began to increase. Initially, the increase was largely due to the
burning of coal, which was the primary energy source for the Industrial
Revolution, and whose exhaust products when burned include
CO2. Since then, the other major fossil fuels, oil and
natural gas, have also become sources of growth in CO2
levels. The latest IPCC report presents statistics over the years since
1970, which are indicative of the historical proportion that fossil
fuel burning occupies in the sources of CO2. The percentage
of emissions from solid, liquid and gas fuels represents about a 70%
fraction of CO2 emissions and has seen its share increasing
during this period.
But other factors contribute as well. For example, the widespread
cutting down of forests can add CO2 to the atmosphere if the
trees are burned; like fossil fuels, they release this greenhouse gas
as well. If the trees are left to rot, that too releases
CO2, albeit more slowly. And because living trees absorb
CO2 in the process of photosynthesis, the cutting of forests
eliminates a source of CO2 removal, so the gas builds up
more quickly than it otherwise might. The same estimates from the IPCC
quantify deforestation and land-use change emissions as about 22% of
CO2 emissions.
Some manufacturing processes add CO2 to the atmosphere
as well. The manufacture of cement is one; it does not just require
energy, which often comes from fossil-fuels, but the chemical reactions
involved in its manufacture release large amounts of the gas as well.
All in all cement production has occupied a 3% share of CO2
emissions. All this said, fossil fuel burning remains the predominant
source of the historical increase in atmospheric CO2
concentrations that added about 100 ppm (36%) over the last 250 years
to the CO2 levels of the pre-industrial era.
- the expected impacts on the climate
Data collected over the past 50 years point to the fact that our
weather is getting more extreme. But trying to isolate the fingerprint
of global warming within the weather is much harder than isolating the
fingerprint of global warming within the climate system. That doesn't
mean it's not there; it just means seeing climate change in the weather
is a much noisier, more chaotic and more complicated process.
Statistical analyses can help us see the story buried beneath the
noise. And climate scientists have come up with some very clever
variations on using a slow motion instant replay of the weather to help
them see how the statistics of extreme events are changing.
It turns out that you can use climate models as an ``instant
replay'' to recreate a specific weather event. Think of it like doing
an autopsy, except it's being performed on a specific extreme weather
event. The European heat wave of 2003, an extreme weather event that
killed over 35,000 people, offers the best example of how climate
models can help us see the global warming embedded within our weather.
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
When you step back and compare the summer of 2003 with summers
past, it becomes even more obvious. As you can see in Figure 3, there
are a series of vertical lines that almost look like a bar code. Each
vertical line represents the mean summer temperature for a single year
from the average of four stations in Switzerland over the period 1864
through 2003. Until the summer of 2003, the years 1909 and 1947 stood
out at the edges as the most extreme temperatures in terms of hot and
cold summers. Climate scientists estimate the summer of 2003 was
probably the hottest in Europe since at least AD 1500.
If climate is what you expect and weather is what you get, then the
summer of 2003 in Europe was way outside the envelope of what anyone
would have expected. Statistically speaking, in a natural climate
system with no man-made CO2 emissions, the chance of getting
a summer as hot as 2003 would have been around once every thousand
years or one in a thousand.
The point of this weather autopsy isn't so much whether the 2003
heat wave was caused solely by global warming. Indeed, almost any
weather event can occur on its own by chance in an unmodified climate.
But using climate models, it is possible to work out how much human
activities may have increased the risk of the occurrence of such a heat
wave. It's like smoking and lung cancer. People who don't smoke can
still get the disease, but smoking one pack of cigarettes a day for 20
years increases your chances of developing lung cancer 20-fold. Thanks
to some sophisticated climate models and well-honed statistical
techniques, scientists can identify the push that global warming is
giving the weather.
This weather autopsy showed that human influences had at least
doubled the very rare chance of summers as hot as the one Europe
experienced in 2003. More specifically, climate models showed that
greenhouse gas emissions had contributed to an increase in 2003-style
summers--moving from a one in a thousand years to at least once in
every 500 years and possibly as high as once in every 250 years. What
is perhaps the most shocking is what happens when you run the models in
forecast mode instead of autopsy mode. If the summer of 2003 had been a
freak event of nature, we could just chalk it up to the luck of the
draw. But according to the model predictions, by the 2040's, the 2003-
type summers will be happening every other year. And by the end of this
century, people will look back wistfully upon the summer of 2003 as a
time when summers were much colder.
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Scientists now believe that the Earth could warm up by more 7+F, on
average, by the end of the century, if emissions of greenhouse gases
continue to grow at current rates. That's significant enough to trigger
all sorts of big changes in the environment. To start with, scientists
expect sea level to rise by three feet or more--partly because water
expands as it warms, partly due to melting ice in Greenland and other
places. Low-lying areas--including significant parts of states like
Florida, and entire countries like Bangladesh and the Maldive Islands
will be much more prone to erosion and to catastrophic flooding from
storm surges. The warming could also make the most powerful of tropical
storms even more powerful. And rainstorms in general are likely to
become more intense, with more of them causing damaging floods.
As mountain glaciers melt, they'll cause even more flooding--at
first. But if they shrink enough, the fresh water they provide will
become scarce. Billions of people in India and China, for example,
depend on water that comes off glaciers in the Himalayas and the
Tibetan Plateau. In the U.S., warmer winters and spring will induce
earlier snowmelt in the Rocky and Sierra Nevada mountains. That means
less meltwater for a thirsty California, especially during the summer
when water is really needed.
In already arid regions (Australia and the American West are just
two examples) droughts are likely to come more often and be more
severe, and they could last longer. That's likely to lead to more
wildfires. Heat waves will be more frequent too, not just in deserts
but in temperate zones, including most of the continental U.S.
All of these changes will have an impact on people, our physical
safety and our ability to grow food and get water. But climate change
could have an even greater impact on the survival of some species.
Plants and animals thrive in certain specific climate conditions. They
cannot easily adapt to the changes that have already begun. The trees
that produce Vermont maple syrup, for example, may have trouble
surviving in Vermont as the New England climate changes, and Georgia
may lose its population of Brown Thrashers--the state bird. Not all of
the changes will happen on land. The warming of the oceans has already
contributed to a worldwide die-off in coral reefs, which is expected to
accelerate as temperatures continue to rise. Corals are home to a wide
variety of sea-dwelling creatures, so when they go, many other species
could be in big trouble.
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Conclusion
When I worked at The Weather Channel, I was constantly awestruck by
the extent to which people rallied around a weather forecast. Whether
it was sandbagging in advance of the Red River flood, or evacuating in
advance of Hurricane Gustav. There's something so inspiring about the
way communities can pull together under these extremely challenging
circumstances. We're clearly pretty good at processing the risks
associated with extreme weather, which is why it's so important for
people to understand that their weather is their climate. As such
climate and global warming need to be built into our daily weather
forecasts because by connecting climate and weather we can begin to
work on our long-term memory and relate it to what's outside our window
today. If climate is cold statistics, weather is personal experience.
We need to reconnect them.
The weather forecast is so engrained in our existence that we know
very well how to make it actionable. If we hear on the radio in the
morning that it's going to rain, we bring an umbrella. If we hear that
the temperature is going to be unseasonably cool, then we pack a
sweater. By definition, weather is a timescale we can't stop. With a
weather forecast, we're strictly working on our defense. However, with
the climate forecast, the necessary actions are not as straightforward,
and this highlights some of the basic philosophical differences between
weather and climate. I've come to view long-range climate projections
as an ``anti-forecast'' in the sense that it's a forecast you want to
prevent from happening. Until now, we've been able to view extreme
weather like flooding as an act of God. But the science tells us that
due to climate change these floods will happen more often and we need
to be prepared for them. I say that a climate forecast is an ``anti-
forecast'' because it is in our power to prevent it from happening. It
represents only a possible future, if we continue to burn fossil fuels
business as usual. The future is ultimately in our hands. And the
urgency is that the longer we wait, the further down the pipeline
climate travels and works its way into weather, and once it's in the
weather, it's there for good.
We are currently in a race against our own ability to intuitively
trust what the science is telling us, assess the risks of global
warming, and predict future impacts. So when we look at a climate
forecast out to 2100 and see significantly warmer temperatures (both
average and extreme) and sea level three feet higher, we need to assess
the risk as well as the different solutions necessary to prevent it
from happening. The challenge is to reduce greenhouse gas emissions,
replace our energy infrastructure and adapt to the warming already in
the pipeline.
Thank you for affording me this opportunity to share with you this
brief history of climate change. I would be pleased to address any
questions you might wish to raise.
Biography for Heidi M. Cullen
In addition to her responsibilities as interim CEO and Director of
Communications, Dr. Heidi Cullen serves as a research scientist and
correspondent for Climate Central--a non-profit science journalism
organization headquartered in Princeton, NJ. Before joining Climate
Central, where she reports on climate and energy issues for programs
like PBS NewsHour, Dr. Cullen served as The Weather Channel's first on-
air climate expert and helped create Forecast Earth, a weekly
television series focused on issues related to climate change and the
environment. Prior to that Dr. Cullen worked as a research scientist at
the National Center for Atmospheric Research (NCAR) in Boulder, CO. She
received the NOAA Climate & Global Change Fellowship and spent two
years at Columbia University's International Research Institute for
Climate and Society working to apply long-range climate forecasts to
the water resources sector in Brazil and Paraguay. She is a member of
the American Geophysical Union, the American Meteorological Society and
is an Associate Editor of the journal Weather, Climate, Society. Dr.
Cullen also serves as a member of the NOAA Science Advisory Board. She
received a Bachelor of Science degree in Industrial Engineering from
Columbia University and went on to receive a Ph.D. in climatology and
ocean-atmosphere dynamics at the Lamont-Doherty Earth Observatory of
Columbia University. Dr. Cullen is the author of The Weather of the
Future published in August of 2010 by Harper Collins.
Discussion
Chairman Baird. Thanks to all of our witnesses.
At this point, I will recognize myself for five minutes,
and we will follow in alternating order as Members wish to have
questions.
The Impacts of CO2 Increases on Temperatures
Just to start with a premise that I don't think people
often appreciate, and I don't think there is any disagreement
on this panel--though I think I have heard disagreement by some
of my colleagues occasionally--that CO2 is essential
to maintain the current temperature of the Earth. If it were
not for CO2 and/or some other greenhouse gas--Dr.
Lindzen?
Dr. Lindzen. Certainly understand if you double
CO2----
Chairman Baird. No, that is not what I am saying. Let me
finish my question.
Dr. Lindzen. The current climate is mostly water vapor and
clouds.
Chairman Baird. Okay. But let me finish the question. It is
established science that the presence of CO2 in the
atmosphere has an important role in maintaining the current
surface temperature of the Earth in the atmosphere. If you did
not have CO2, would the Earth be a cooler place or a
warmer place?
Dr. Lindzen. It would be approximately 2-1/2 degrees
cooler.
Chairman Baird. Any others wish to comment on that?
Dr. Cicerone. I think it would be a much bigger effect than
that.
Chairman Baird. Hit the mic.
Dr. Cicerone. In the mid-1980s, Bob Dickinson and I did
some of the earliest calculations of the radiative forcings.
And Bob is one of the few geniuses in this field. And when he
tried to do the experiment that you just referred to, to figure
out what impact the current amount of CO2 is having,
the calculations broke apart because the disruptions in the
atmosphere were so large that he had to go back and start over.
I think it would be far more than 2-1/2 degrees.
Chairman Baird. Let me ask a second question. Is there any
doubt that CO2 absorbs more heat than oxygen?
Dr. Cicerone. No.
Humans Have Caused Increases in Atmospheric CO2
Chairman Baird. No doubt about that. Is there any
doubt that human activity has increased the amount of CO2
in the air? No doubt of that. That is a given.
Dr. Lindzen. How shall I put it? I would advise you to stop
with the no doubt. But, you know, that is the prevailing view.
Chairman Baird. Okay. Fair enough. Okay. I am a Ph.D.
scientist. I understand that science is never 100 percent,
Doctor. But I would say the prevailing view and abundant
evidence suggests that humans have caused a substantial
increase of CO2. Is that fair?
Dr. Lindzen. Yeah.
The Greater Proportion of Record High Temperatures
Chairman Baird. Okay. Now, here is the question. Is there
disagreement with Dr. Meehl's analysis and Dr. Cullen's
analysis and Dr. Cicerone's of greater proportion of record
highs in recent years relative to record lows? Each person will
need to use their mic when they speak.
Dr. Lindzen. Yeah. I don't think they are meaningful
statements. I mean, during this whole period that he is
referring to, if you look at it, it still looks like a random
process, one. And two, the instrumentation has changed
dramatically during that period so that the response time of
modern thermometers is almost infinitesimal compared to the
ones used in the earlier part of the record.
Chairman Baird. Actually, I will rephrase my question
because I think it was pretty clear, but your answer didn't
address it. My question is: Is there a doubt that in the recent
years--and I will state it as clearly as I can--there is a
greater preponderance of record highs than record lows? Unless
you are suggesting in the past that the measurement devices
were erroneous in one direction and not another.
Dr. Lindzen. Absolutely, because you have high response
time. You will pick up perturbations----
Chairman Baird. I am not talking perturbations. Simply are
we suggesting Dr. Meehl, Dr. Cullen--if you are suggesting that
the thermometers today are more sensitive to increases than to
cooling----
Dr. Lindzen. Yeah. Oh, yeah.
Chairman Baird. That is right. That is your----
Dr. Lindzen. I think that is pretty much true. But there is
another issue here which is a bit weird; namely, why do we have
record highs and record cold on any given day?
Chairman Baird. I don't want to ask the why first. I just
want to get the facts.
Dr. Meehl, Dr. Cullen, Dr. Cicerone, is it generally
accepted scientific fact that there are more record highs today
than record lows? Dr. Meehl.
Dr. Meehl. Yes.
Chairman Baird. Dr. Cullen?
Dr. Cullen. Yes.
Chairman Baird. Dr. Cicerone?
Dr. Cicerone. Yes.
Chairman Baird. Dr. Lindzen may disagree with that. It
seems to me that that is a fairly objective piece of evidence
that we could look at, that there are more general record--you
may disagree, but part of what is happening here is that we
have a preponderance of folks. If I look at a temperature, a
thermometer, and I say this is pretty hot, other people could
say it is pretty cold. But if we have got a measurement device
we have been using for a very long time and it is showing a
hotter temperature than what it showed a year ago, either the
measurement device has changed or the temperature has changed.
Maybe the measurement device has changed, but we are talking
thousands of measurement devices changing and only in one
direction.
Dr. Meehl.
Dr. Meehl. May I just add a little bit to that? This
analysis we did, we were looking at basically temperature
records in the second half of the 20th century from weather
stations that had good daily records. And this is actually, I
think, a bigger problem than the thermometer problem. You have
to have stations recording their daily high temperature and
daily low temperature every day so you can have a lot of daily
records.
And this ratio, which is now 2-to-1, which we thought was
kind of odd, we thought initially--in fact, this came from a
guy at The Weather Channel, because he was noticing this. He
was keeping track of records on his own. He is a meteorologist.
And Heidi invited me down there. And he said, what is with this
2-to-1 ratio? I said, I don't know. He said, Well, is that some
kind of unique thing about climate change? I said, I have no
idea. I said, Let's look at it.
So we started looking at it and it turns out this ratio--we
just happen to be at about 2-to-1 right now. A decade ago it
was a little less than 2-to-1, and a decade before that it was
a little less than that. If you had a climate that wasn't
changing, you would expect that ratio to be about 1-to-1,
because you would have an equal chance of getting record highs
and record lows.
So I think what was interesting about that study is it
showed--and I think this is a thing that we have trouble
communicating to the public, but climate change is a shift in
statistics, it is a shift in the odds of certain things
happening. So as you warm the average temperature, you just
have a greater chance of extreme warm temperatures and less
chance of extreme cold temperatures.
Chairman Baird. Thank you.
Dr. Cullen. And if I could just build on that very quickly.
What Jerry did was he carried that thought experiment forward,
which is part of the exercise that we all need to go through.
And what they found was if we continue to make greenhouse gas
business as usual, by the middle of the century that would then
become 20-to-1. So it gets worse as you move forward in time.
Chairman Baird. Because of the shifting and the
probability.
Mr. Inglis.
Quantifying Climate Sensitivity and Water Vapor
Mr. Inglis. Thank you, Mr. Chairman. I notice the
discrepancy in some numbers here. Dr. Lindzen said that a
doubling of CO2 would cause a one degree C increase
in temperature. Doubling of CO2 would cause a one
degree increase in----
Dr. Lindzen. I said by itself. In other words, absence of
feedbacks--and this the IPCC says also--you expect about one
degree from changing CO2 from 280 to 560. You again
get the same thing for a doubling from 560 to 10,120. It is
nonlinear. It is logarithmic. So every molecule of CO2
does a little less than its predecessor. But one degree is what
you expect from a doubling. Anything more is due to the
positive feedbacks, from water vapor and clouds primarily. In
the models.
Mr. Inglis. I am going to ask the others to say whether
they agree with that. Dr. Cullen, I think I heard you say it is
an eight degree Farenheit rise, right? So it is----
Dr. Cullen. No. The basic climate sensitivity doubling of
CO2 experiments suggests an eight degree Farenheit
rise. That was the Svante Arrhenius calculation. IPCC estimates
give a range, including all the feedbacks.
Mr. Rohrabacher. I didn't hear the answer. What did she
say?
Mr. Inglis. Somebody help me explain that. Maybe Dr.
Cicerone wants to try that.
Dr. Cicerone. Yes. What Dr. Lindzen is saying is if we
could isolate the impacts one by one, the CO2 effect
itself and the way it interacts with the planetary radiation
would cause about a one degree warming under these
circumstances Centigrade. It's the additional forcing, which I
mentioned in my testimony briefly, of adding more water that
causes part of the increased effect.
Part of it would be due to the way clouds are being treated
in the calculations, also. But if I focus on the water, that's
when I mentioned the disproportionate amount of evaporation
increase as we warm a body of water. This is just a fact of
physics. So that people who propose that this enhancing effect,
which Dr. Lindzen denies, people who propose to deny that
enhancing effect are fighting against a very fundamental part
of physics.
Dr. Lindzen. May I respond?
Dr. Cicerone. The fact that the rate at which a liquid
evaporates is a grossly disproportionate function of the
temperature.
Dr. Lindzen. May I respond?
Mr. Inglis. Please.
Dr. Lindzen. What Dr. Cicerone is referring to is the
Clausius-Clapeyron relation. That is a relation that tells you
what the saturation vapor pressure is for water as a function
of temperature. The atmosphere, first of all, is almost never
saturated. So the basic physics that Cicerone is referring to
is stating if you have a big bottle and somebody has this cup,
no matter what I have done to pour water into each, this will
always have more. That doesn't make much sense.
But the other thing is the data are----
Mr. Inglis. Let me stop you right there. What does that
mean? Dr. Cicerone, what is your response to that?
Dr. Cicerone. I didn't follow him. I know the Clausius-
Clapeyron equation.
Chairman Baird. You need to turn your mic on.
Dr. Cicerone. I know the relationship he is speaking of. I
know the relationship with the entropy and thermodynamic
quantities, and I don't understand what he is saying.
Dr. Lindzen. I am saying it's the saturation vapor
pressure, right?
Dr. Cicerone. Yeah, sure.
Dr. Lindzen. Okay. Is the atmosphere saturated?
Dr. Cicerone. No, we have a more or less relative humidity,
on average, of 70 percent.
Dr. Lindzen. Yeah, fluctuating all over the place.
Dr. Cicerone. Yeah.
Dr. Lindzen. Clausius-Clapeyron tells you nothing about
that.
Dr. Cicerone. It gives you an approximation to the slope.
Chairman Baird. I will ask both gentlemen to use your mics.
Dr. Lindzen. Okay.
Dr. Cicerone. We can get an approximation to the slope.
That is the way----
Chairman Baird. You need to turn your mic on. Go ahead and
leave it on.
Dr. Cicerone. All right.
The way the evaporation takes place can be also
approximated by the thermodynamic quantities that give the
slope of the relationship. And it's just a rapid increase. It's
very hard to hold back the vapor pressure of a liquid against
this relationship, whether it's evaporating into gas above it
that's saturated or not.
Mr. Inglis. Yes, Dr. Meehl.
Dr. Meehl. Yeah, I was just going to add that this quantity
we are talking about, which is an equilibrium response of the
climate system to a doubling of CO2, actually has a
history to it that goes back to the early days of climate
modeling, which that's about all you could do, would be to
double the CO2 and see what happens. So it has ended
up being this kind of equilibrium climate sensitivity. And that
actually goes back even earlier than that. We will never
actually see the equilibrium value because it takes so long for
the oceans to catch up. So this is a kind of metric we use to
gauge, give us a rough calibration of how the climate system
may respond. So these are kind of relative numbers.
But I think maybe the point is that there is a range of
what we think this number may be. The current range we think is
anywhere between two degrees Centigrade and 4-1/2 degrees
Centigrade. This number was derived a lot of times from models,
but now we have multiple lines of evidence. People have
actually looked at observations, they have looked at the
response of the climate system to big volcanic eruptions, they
have looked at paleoclimate data. So now we have multiple lines
of evidence that seem to suggest that that's probably about the
right range and that the most likely value is actually around
three. And I think Dr. Alley is going to say a lot more about
this in Panel II.
Mr. Inglis. Thank you.
Thank you, Mr. Chairman. I am out of time.
Chairman Baird. Dr. Bartlett.
The Common Cause for Clean Energy Development
Mr. Bartlett. Thank you very much.
This hearing today I think is one of the more important
things that the Science Committee needs to do. There should be
no dispute as to what the facts are relative to climate change,
and there is a lot of dispute as to what the facts are. There
can be a great deal of dispute as to how you interpret those
facts. But before you can have an honest discussion, you need
to agree on the facts, and we don't now agree on the facts. So
I really appreciate the Chairman holding this hearing and thank
the witnesses for their contribution to this.
The Chairman's question, if there was no CO2,
would the Earth be colder? Not if there was just a little bit
more water vapor. Because water vapor is a hugely more
important greenhouse gas than CO2. I know the
Chairman meant that if all other things remained equal would
the Earth be colder if there was no CO2? And, of
course, it would. But CO2 is a pretty small
greenhouse gas compared to water vapor. That doesn't mean that
it's not important, because it can be the tipping point.
There are three groups that have common cause in wanting to
reduce the consumption of fossil fuels; and, regretfully, they
are at each other's throat rather than joining hands and
marching forward.
One group is a group that is represented today, those who
are concerned about climate change and the effect that the
CO2 produced from burning fossil fuels would have on
that.
A second group is a group that is really concerned that the
United States has only two percent of the known reserves of oil
in the world, and we use 25 percent of the world's oil, and we
import just about two-thirds of what we use. And the solution
to that, obviously, is to stop burning so much fossil fuel and
use alternatives, which is exactly the same solution that we
have today in looking at the effect of CO2 on
climate. We would like to produce less of it by moving to
alternatives which do not produce CO2 if you have a
short cycle rather than a million-year cycle like we have in
fossil fuels.
And the third group that has common cause in this--and I
just happen to have a paper this morning that just came out,
the World's Energy Outlook for 2010 now out. And I will try to
have this thrown on the screen later today, because it is
really a startling picture. It shows that we have now peaked in
conventional oil production at about 65 million barrels a day.
The total world production is about 84. The rest of that is
made up of natural gas liquids and unconventional oil. This
chart has that plummeting to about 15--only about 15 million
barrels a day by 2035. That's just 25 years from now. And it
has the difference made up--because they have plateaued
essentially with production of oil. And the difference is made
up, and it's I think about 42 million barrels per day, they say
that we are going to get from fields yet to be developed or
found. You know, that's the impossible dream. That's not going
to happen.
Now, the solution to this problem, the fact that the fossil
fuels just aren't going to be there to burn, is to move to
alternatives. And so whether or not you are right that the
increase in CO2 is producing climate change, there
are two other very good reasons for doing exactly what you want
to do, and that is to move away from fossil fuel use to
alternatives.
Why aren't these three groups locking arms and marching
together? Because they have exactly the same solution to very
different problems. What keeps you from doing that?
Dr. Cullen. I think the three groups have locked arms and
have moved together. But I think there is a lot of opposition.
I think it's a very difficult thing to change one's invested
infrastructure. And I think much of the discussion about
climate change and alternative energy is making that leap and
moving forward and embracing new technologies. So, you know,
can we do a better job? Absolutely. But I do think that our
three communities have aligned and, you know, it's clear that
there are multiple reasons to shift away from fossil fuel.
Mr. Bartlett. You know, even if your premise is not
correct, that is, that human production of CO2 is
not changing the climate, what you want to do about it is
exactly the right thing to do for two other very good reasons.
Again, I ask why do not these three groups, instead of
sniping at each other's premise and ridiculing each other, why
don't you just lock arms and march forward? Because the
solution to these three very different problems is exactly the
same solution: less fossil fuels and more alternatives.
Thank you, Mr. Chairman, for holding this hearing.
Dr. Lindzen. Would you like an answer?
Mr. Bartlett. Yes, sir.
Dr. Lindzen. It's profoundly dishonest. And I think
integrity is important. I think Mr. Baird emphasized that. If
somebody is asking you how climate changed and you influence
your answer because you have some ideas on energy policy, you
are short-changing your interlocutor. And I don't think that's
appropriate. If somebody has an energy policy they wish to
propose, it should be defended on its own grounds and sold on
its own grounds.
The notion that a climate scientist who disagrees that
CO2 is important there should join the bandwagon--or
even if they did agree, to say to push my view of greenhouse
gases I will also support your view of energy, it's confusing
the issue for the public. It's not helping it for everyone to
march in lockstep.
Mr. Bartlett. Sir, in a former life I was a scientist. I
have a Ph.D. I have about a hundred papers in the literature. I
understand science. And I am a rare Republican. I tell
audiences that I am a conservative Republican, but on these
kind of issues I am not an idiot.
Dr. Lindzen. I am not accusing you of that. But I am saying
that when you ask a scientist to lock arms with a politician
because they both have aims that have the same policy, that's
probably dangerous.
Mr. Bartlett. If the goal you want to accomplish is a
national security goal--and, ultimately, it is--then I don't
see a compromise of science because you happen to have a common
goal with a political or a military person.
Chairman Baird. Dr. Bartlett, if I may, as well as I know
Dr. Bartlett, I would never expect Dr. Bartlett to suggest that
a scientist should modify his or her findings to fit a
political agenda. This, by the way, goes to both sides. But I
do believe what he is suggesting, and he suggested it many
times--and not only does he suggest it in hearings, he embodies
it in his life--that there are national interests that are
meritorious beyond single aims. I mean, the debate today is
about the scientific findings. I think what he is saying and
what he has literally embodied in his own life--he is more off
the grid than anybody I know, and I mean that as a compliment.
He is off the electricity grid because he is so on the grid of
the data. He is saying, I think, that this is not a matter of
distorting the scientific findings, but let's make our policy
consistent with the common interests.
Mr. Bartlett. Yes, sir. We have three common interests, and
there is no reason that we should be limiting our ability to
reach those common goals because we simply disagree with each
other's premise. That's all I am saying.
Chairman Baird. Dr. Cicerone, I know you want to comment,
but I am going to invite Mr. Rohrabacher, who has rejoined us.
If we have time, I will get back to you on this matter because
I know it's important. Mr. Rohrabacher.
Climate Skepticism
Mr. Rohrabacher. Thank you very much, Mr. Chairman.
And, again, we will miss Chairman Baird. I appreciated his
leadership, although we have strongly disagreed on several
issues, this being one of them. And I actually would thank him
very much for including one witness out of four to present the
other point of view.
The fact is, in the past, as Ranking Member Hall mentioned,
we have had one witness in a whole hearing, as compared to any
type of balanced presentation. This has been--this tactic of
not permitting the other side to be heard or trying to muzzle
people in academe and elsewhere from expressing opposition
views to the manmade global warming theory is a travesty, and
it's about time that people in the scientific world admit that
that's what's been going on. Because what we have had is, yeah,
one witness out of four; in the past, we had one witness out of
16.
And how many of us have heard over and over again ``case
closed'', where there are presentations with nobody on the
other side being able to express their opinion. They have made
a mockery out of science. And I am very happy that at least
today we have one witness out of four in the panels who are
going to present the other side.
Because there is a fundamental disagreement on whether or
not the climate cycle that we are in today is basically being
caused by mankind or whether or not this is a natural cycle.
And if it is created by some sort of human activity, is it
something that we should be concerned about because it is not a
major factor but a minor factor in what's going on?
Mr. Chairman, I noted that you used your case to say why
CO2 should be of more concern in terms of--because
it adjusts the oxygen in the atmosphere because CO2
does absorb more heat. Well, let us just note that oxygen is, I
believe, 21 percent of the atmosphere. CO2 is 390
parts per million. That's one-half of one-tenth--less than one-
half of one-tenth of one percent of the atmosphere as compared
to 21 percent. Of this, 58 parts per million are manmade as
compared to what's in there naturally.
So this idea that CO2--most people who are
discussing this issue, the presentation to the public has been
so skewed and the debate has been so hampered by not presenting
the other side that most people believe that CO2
represents ten percent or 20 percent of the atmosphere. Ask the
people around you, and you will find even Members of Congress
giving you that answer.
Well, today, we are trying to get to the bottom of this;
and I appreciate the fact that, again, we are having a debate
where at least one out of four witnesses is going to be able to
address some issues.
Let me ask Dr. Lindzen some of the points that you have
made. I would like to specifically ask you whether or not you
believe that there will be dire consequences due to our
lifestyle on the climate of this planet.
Dr. Lindzen. No, I don't think so. I think--we are talking
about finite issues. The elevation of finite issues to
catastrophism probably would leave behind a large portion of
the scientific community.
I think there has been a problem that the agreement is on
the trivial. The controversy is on really obscure things that
depend on many factors. I mean, one of the things that bothers
me in this in the discussion of extremes and storms and so on,
a basic feature of meteorology is the cause of storms in mid-
latitudes is the temperature difference between the Equator and
pole. Under a warmer climate, that should be reduced, and that
should lead to fewer storms. It is the storms that bring in
record highs and lows by carrying air from distant places. Why
suddenly in this complex thing a particular observation that is
actually contrary to the basic physics assumes importance, I
don't know.
Mr. Rohrabacher. We have had many cycles of warming and
cooling throughout the history of this planet, many, many
cycles. And a minuscule change in the amount of CO2
in the atmosphere, as compared to other time periods when there
were other cycles going on, when CO2, by the way,
was dramatically higher than what it is today, we have seen
that the relationship between CO2----
This is what it comes down to. People are trying to tell
us--in the scientific community, there are people trying to
tell us that we have got to accept Draconian changes in our way
of life mandated by law because the CO2 that we are
emitting is going to cause drastic consequences to the planet's
climate. That does not seem to hold up.
Dr. Lindzen. It's also that even if the U.S. shut down
period, retired from the world, its impact on the CO2
levels would be rather undramatic.
Mr. Rohrabacher. And the CO2 levels in the
atmosphere are rather undramatic.
Dr. Lindzen. Yeah.
Mr. Rohrabacher. The fact is CO2 is a minor,
minuscule part of the atmosphere. Its increase during the time
period where mankind has increased the standard of living of
the people of the human race has been used as a scare tactic to
frighten people into accepting controls over their lives that
they otherwise would not accept. That's what this debate is all
about. And, frankly, I have seen in the past--I am a former
journalist. I have seen example after example where people in
the political world will try to frighten the public on an issue
in order to achieve a political end, and this is one of the
worst examples of that that I have seen.
Thank you very much, Mr. Chairman.
Chairman Baird. Mr. Rohrabacher, whereas you began your
statements by emphasizing the importance of hearing from all
sides and during the most recent questioning you heard from one
side, I am going to invite the witnesses if they--other
witnesses if they wish to respond to some of the points that
you made to do so, because I am sure you would want to hear
their responses.
Dr. Meehl. There was a number of different points made
there. I don't know quite where to start. Maybe I will just
take a couple of them.
This is one of the things that I personally find difficult,
that a lot of times the science gets kind of blurred together
with the political side of this issue. What we are here to talk
about is the science of this issue. When you talk about dire
consequences, those are value judgments made by human societies
that aren't science issues.
You know, there has been an effort in the European
community to come up with a number of two degrees sea warming
above preindustrial as a threshold for dangerous climate
change, and people argue about that a lot. And that number is
out there, but I think you would find a lot of disagreement
even among the scientific community about what constitutes
dangerous climate change.
Certainly with climate change things will shift around. You
will have dry areas probably getting dryer; wet areas will get
wetter. You will see changes to extremes. You see things that
would have impacts on human societies.
But the fact that these greenhouse gases, which we call
trace gases--because, as you point out, rightfully so, they
constitute a really small fraction of the composition of the
Earth's atmosphere--the fact that they have this interesting
and unique property that they have more than two atoms per
molecule. Oxygen and nitrogen, which are the biggest
constituents, as you say, have only two atoms per molecule,
when you have more than two atoms per molecule that makes that
molecule really active and really important, and it can absorb
and reemit heat and trap it. So I think that----
Mr. Rohrabacher. But if it's so minuscule, how does that
then have a greater impact?
Dr. Meehl. See, that's the interesting thing about it.
Because even at these really small quantities they can be
really important to the climate system and really make a
difference in how the climate of the Earth is behaving. So I
think in terms of the science, these are the things that we
grapple with, too. You know, we try to incorporate these things
in the models the best we can, and we try to use the tools the
best we can, and these are the indications that we get.
In terms of evidence, science is a great thing because, you
know, Dick Lindzen has his theories about low climate
sensitivity. Other people have tried to use other evidence to
contradict what he said, and this is how science works. We have
this ongoing discussion, and at the end of the day try to come
up with some idea of what we think is really going on out there
in the world. So I think that's why all of us probably got into
science in the first place, because we are really interested in
how the world works.
But, you know, focusing on the science makes it a very
interesting problem that has all these interesting things that
go on in terms of physical processes that we can try to use
tools like climate models to understand. And I think that's
where the interest is for us. I think that's what makes this a
very interesting problem.
Now, as far as what you decide to do as policymakers about
this problem is something we can try to give you information
on. I think Mr. Inglis' example of the advice you get from
doctors that maybe 98 give you A, and two say B, and you say,
well, okay, what do you want to do? It's still a call that you
have to make as policymakers as to what you do with this
information. But I think we have to do the best we can to give
you the best possible information from our community.
Chairman Baird. So help us understand.
First of all, I very much appreciate what you said, Dr.
Meehl, because on this committee and elsewhere in the public
and the media there is an assertion that climate science is a
hoax, meaning something intentionally perpetrated. Piltdown Man
is a hoax, but I don't see this as a hoax. People may disagree
on the findings and implications and the models, et cetera, but
the idea that it's a conspiracy to force Draconian changes or
that it's a hoax flies in the face of what I know about the
individuals on all sides before us today. And so, if nothing
else, let us put to rest this assertion that in some way you
are motivated by some bizarre intent to change our way of life.
Help us understand, though, the fundamental question that
Mr. Rohrabacher asked about how a relatively small trace
element impacts raising temperatures. That's really----
Mr. Rohrabacher. As compared to the natural cycles.
Chairman Baird. That's a fair question. That's a fair
question. Help us understand that. Dr. Cicerone. I am going to
call on--we will work our way down.
Dr. Lindzen. I will be happy to answer that.
There is no simple relation between the amount of a
constituent and its ability to absorb radiation. If you have a
very strong absorbing molecule, then you need less of it to do
something.
CO2 is a significant absorber. I differ with my
colleagues about the reason why. It's the permanent dipole
moment that's important. You know, OH, NO, all have two atoms
and they absorb well in the infrared. So, I don't know, that
makes me wonder about the testimony.
But, still, it is possible for a trace gas to be important.
It isn't strictly the amount, even though the amount is
minuscule. For instance, a very thin visibly invisible cloud
will absorb more infrared than all the other infrared absorbers
in the atmosphere when it's present.
Chairman Baird. Dr. Cicerone.
Dr. Cicerone. The framework is the energy balance of the
planet. And so in deciding whether an entry is small or
diminutive or whatever, it's when we look at those balancing,
as you said, Mr. Rohrabacher, compared to the natural balances.
And these polyatomic molecules that have vibrational and
rotational modes that they can interact with the infrared
radiation, as Dr. Lindzen just said, sometimes the tiniest
presence can intercept parts of the spectrum which are
otherwise transparent.
Generally speaking, the Earth's atmosphere is transparent
in some of these infrared wavelength regions where the planet's
emitting. So it's not too much of a mystery. We have to go
through the numbers.
If I may, Mr. Chairman, could I make a comment on Mr.
Bartlett's very interesting puzzle about energy policy?
Chairman Baird. Please. And then I will give one more
opportunity to others, and then we will finish. We have two
more panels to get through.
Dr. Cicerone. I have heard a very graphic presentation of
the same three conundrums in testimony to the House from a
former CIA director, Jim Woolsey, where he gets back to your
three overlapping groups and interests by having a fictional
conversation between John Muir, Mahatma Gandhi, and General
George Patton. And he shows that they can agree on the kinds of
things that you just said. He testified in the House a year or
two ago, and I have heard him give this presentation. It's
fascinating.
Getting down to basics, energy efficiency is a solution
that should appeal to all three of your groups; and yet if all
of this free money is lying on the floor to be saved with
energy efficiency, why aren't more people taking advantage of
it? We now have some analysis from business groups of why
various companies and individuals are not doing more to capture
this free energy through efficiency, and I am optimistic that
people will get their acts together who are concerned about
those three different sides of the issue.
Chairman Baird. Any final comments by Dr. Meehl or Dr.
Cullen? And then we will release this excellent panel for the
next one.
Dr. Cullen. I think one remark I would like to simply make
is that with this notion that extreme weather events will
increase over time, I think it's important to just remember
that in our daily lives as we move forward there are numerous
things we all need to worry about. And if you look at the
tragic events that happened during the national floods, yes, we
dealt with extreme weather events in the past, but from an
infrastructure standpoint, from doing things in the short term
to reduce to our overall vulnerability, I think rather than
think about catastrophes it's thinking about the fact that we
have information that can reduce our overall vulnerability,
make our communities stronger.
And, you know, I just come back to the fact that, just as
meteorologists on the short term are trying to keep people out
of harm's way, this is information that is ultimately meant to
make our communities stronger and safer. And it's sort of as
simple as that as we move forward over the next decade or two.
Chairman Baird. Dr. Meehl, any final comment?
I want to thank this outstanding panel for their expertise,
for their years of work, and for modeling a productive and
constructive discussion. Thank you very much.
We will recess for about four or five minutes until the
next panel can be seated. I am sure my colleagues join me in
thanking this panel of witnesses, and I will ask them to retire
at this moment and invite our others to join us.
[Recess.]
Panel II
Chairman Baird. I appreciate everyone joining us again. We
now will begin our second panel.
As before, it's my pleasure to introduce our second panel
of witnesses: Dr. Patrick Michaels is a Senior Fellow in
Environmental Studies for the Cato Institute. Dr. Benjamin D.
Santer is an Atmospheric Scientist for the Program for Climate
Model Diagnosis and Intercomparison at Lawrence Livermore
National Laboratory. Dr. Richard B. Alley is the Evan Pugh
Professor for the Department of Geosciences and Earth and the
Environmental Systems Institute at Pennsylvania State
University. And Dr. Richard Feely, from my home State of
Washington, is a Senior Scientist for the Pacific Marine
Environmental Laboratory with the National Oceanic and
Atmospheric Administration.
As our witnesses observed before, we do our level best to
try to stick to five minutes. Sometimes if you go a little bit
over I will be as patient as I can. But please do your best to
keep it at five minutes. And following the presentations, we
will have a series of questions. Again, I thank our witnesses.
Dr. Michaels, you are welcome to begin. Thank you.
STATEMENT OF PATRICK J. MICHAELS, SENIOR FELLOW IN
ENVIRONMENTAL STUDIES, CATO INSTITUTE
Dr. Michaels. Thank you, Congressman Baird. It's very nice
to be here. It's an honor to be here.
I think the first panel set what I think what is an
interesting scientific discussion. What we are really looking
at here is to whether the sensitivity of temperature to carbon
dioxide is as large as some people think or whether there are
other factors that are responsible for the temperature changes
that we have seen.
I would like to show the first slide, if I could.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
The important thing about climate change to remember is
that it doesn't matter whether people change the climate. One
of the rhetorical devices that is inaccurate on this is to say
all scientists agree that human beings have an influence on
climate. So what? What matters is how much we influence the
climate. And we are getting some guidance from Mother Nature on
this, despite our best efforts, if you will.
This slide shows--each piece of colored spaghetti on this
slide is a computer model. There are 21 different models from
the United Nations IPCC scenario for concentrations in the
atmosphere that pretty much resemble what's been going on in
the atmosphere. One of the things you see is each one of those
pieces of colored spaghetti is pretty much a straight line, and
the reason for that is because we put carbon dioxide in the
atmosphere exponentially, but the response is logarithmic, and
it tends to do that.
Now, ask yourself the question: Since the planet started
its warming of the late 20th century, has the warming been a
straight line? And the answer is yes. So how do you
discriminate between these straight lines? The same thing you
tell students in weather forecasting, which I have taught. When
different models say different things, look out the window. And
when you look out the window, what you see here is at the low
end of this line.
Now, I hope it went to the next image. Very good.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Another way to look at this issue is to look at the
frequency distribution of temperatures produced by all these
temperature trends produced by all these models for periods say
of five on out to 15 years. And the blue line are the observed
trends from the Climate Research Center--Climate Research Unit
at East Anglia. And what you can see, which corresponds to what
we saw on the last slide, is in fact the warming is clearly
below the average predicted by these models. Yes, we have a
greenhouse gas fingerprint, and we are going to hear about that
in this talk. But I submit to you that it's a pinkie. It's not
one of the dreaded other fingers.
And, furthermore, if we take a look at the attempts like
this, they are very sensitive to the years that are chosen.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
This particular paper right here is probably the most
famous paper ever published on attribution of climate change.
It appeared in 1996, and it shows that the temperature between
1963 of the free atmosphere and 1987 corresponded remarkably to
what was modeled. It was fantastic. It was a wonderful result.
And here is the left-hand side, is the computer.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
You can see in the Southern Hemisphere, which is on the
right-hand side of the left-hand image, a massive warming, and
you see from 1963 through 1987 in the Southern Hemisphere a
massive warming. What a wonderful finding. But the weather data
actually begins in 1957, the weather balloon record for this,
and it ends in 1995 for the purposes of a paper published in
1996.
I offer you the observation by the way, this paper appeared
four days before probably the most important conference on
climate change ever held by the United Nations Policy
Committee; and it was highly, highly influential.
At any rate, when you add in all the data from 1957 through
1995, the relationship vanishes. So these studies are very,
very sensitive to what goes on with the temperature--what
period we study, rather.
So the search goes on. Sulfates, aerosols, the sensitivity
or the effect of them is estimated between zero and minus two
watts per meter squared. You can pick pretty much any value you
want, which makes it very easy to fit curves.
Then there is the problem of volcanoes. After this
appeared, another research effort was made to look at the
effect of volcanoes on the temperature. You see, scientists
actually are involved mainly in trying to find out why it has
warmed so little compared to the greenhouse-gas-only models.
And so a paper came out by pretty much the same group that
said, well, if we go back to Krakatoa in 1883 and we factor in
the volcanoes, my God, 2/3 of the warming that would have
occurred has been suppressed. Wow.
That's another remarkable finding that turns out to be
incredibly time-dependent. Because, you see, there were
volcanoes before 1883. Mount Tambora went off in 1815, created
the year without a summer, 1816. We have these records.
And, very recently, Jonathan Gregory just got a paper
accepted, and it will be published very soon, which uses the
entire volcanic record.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
And I offer you this is an artifact of experimental design
caused by the models having been spun up to a steady state with
episodic volcanic forcing before the historical simulations
began. This artifact could be misleading in comparison and
attributions observed and simulated changes in climate.
So I will tell you what my conclusion is.
First of all, scientists works by tentative hypotheses, and
you look at data to see whether you can maintain your tentative
hypothesis or whether you have to modify it. My tentative
hypothesis would be that the sensitivity has been
overestimated, in agreement with Lindzen and Spencer and a
whole host of other scientists; and that is the prospect that
we need to test.
Now, I realize some people might not agree with me on this,
because some people say there is no such thing as climate
change, and some people say, well, yes, climate change is the
end of the world. If you disagree, you can join this Facebook
site that appeared and you can take care of me.
Thank you very much.
[The prepared statement of Dr. Michaels follows:]
Prepared Statement of Patrick J. Michaels
Thank you for inviting my testimony. I am a Senior Fellow in
Environmental Studies at the Cato Institute and Distinguished Senior
Fellow in the School of Public Policy at George Mason University. This
testimony represents no official point of view from either of these
institutions and is tendered with the traditional protections of
academic freedom.
My testimony has four objectives
1) Demonstration that the rate greenhouse-related warming is
clearly below the mean of climate forecasts from the United
Nations Intergovernmental Panel on Climate Change (IPCC) that
are based upon changes in atmospheric carbon dioxide
concentrations that are closest to what is actually being
observed,
2) demonstration that the Finding of Endangerment from
greenhouse gases by the Environmental Protection Agency is
based upon a very dubious and critical assumption,
3) demonstration that the definition of science as a public
good induces certain biases that substantially devalue efforts
to synthesize science, such as those undertaken by the IPCC and
the U.S. Climate Change Science Program (CCSP), and
4) demonstration that there is substantial discontent with
governmental and intergovernmental syntheses of climate change
and with policies passed by this House of Representatives.
``Climate change'' is nothing new, even climate change induced by
human activity. What matters is not whether or not something so obvious
exists, but to what magnitude it exists and how people adapt to such
change.
For decades, scientists have attempted to model the behavior of our
atmosphere as carbon dioxide and other greenhouse gases are added above
the base levels established before human prehistory. The results are
interesting but are highly dependent upon the amount of carbon dioxide
that resides in the atmosphere, something that is very difficult to
predict long into the future with any confidence. It is safe to say
that no one--no matter whether he or she works for the government, for
industry, or in education--can tell what our technology will be 100
years from now. We can only say that if history is to be any guide, it
will be radically different from what we use today and that therefore
projecting greenhouse gas emissions so far into the future is, to
choose a word carefully, useless.
One thing we are certain of, though, is that the development of
future technologies depends upon capital investment, and that it would
be foolish to continue to spend such resources in expensive programs
that will in fact do nothing significant to global temperature.
Fortunately, despite the doomsaying of several, we indeed have the
opportunity to not waste resources now, but instead to invest them much
further in the future. That is because the atmosphere is clearly
declaring that the response to changes in carbon dioxide is much more
modest that what appears to be the consensus of scientific models.
Testimony Objective #1: Greenhouse-related warming is clearly below the
mean of relevant climate forecasts from the IPCC
Figure 1 shows the community of computer model projections from the
IPCC's ``midrange'' scenario. Observed changes in atmospheric carbon
dioxide concentrations correspond closer to this one than to others.
You will note one common characteristic of these models: they predict
warmings of a relatively constant rate. This is because, in large part,
the response of temperature to changes in atmospheric carbon dioxide is
logarithmic (meaning that equal incremental increases produce
proportionally less warming as concentration increases), while the
increase in carbon dioxide itself is a low-order exponent rather than a
straight line. This combination tends to produce constant rates of
warming.
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Figure 1. Projected temperature rise over the course of the 21st
century from climate models used in the IPCC's Fourth Assessment Report
(colored lines) running a `midrange'' emissions scenario, with observed
temperatures superimposed (red circles).
The various models just produce different quasi-constant rates.
Divining future warming then becomes rather easy. Do we have a constant
rate of warming? And if so, then we know the future rate, unless the
functional form of all of these models is wrong. And if this is wrong,
scientists are so ignorant of this problem, that you are wasting your
time in soliciting our expertise.
How does the observed rate of global temperature increase compare
to what is being projected? For that, we can examine the behavior of
literally hundreds of iterations of these models. For time periods of
various lengths, some of these models will actually produce no
significant warming trend (as has been observed since 1996), or even a
short-term interval of cooling.
Figure 2 gives us the mean and 95% confidence limits of the
midrange family of IPCC models as well as temperatures observed by the
Climate Research Unit at the University of East Anglia. (More will be
said on this history below). It is quite apparent that the observed
rates of change are below the mean value forecast by the IPCC.
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Figure 2. Range of climate model probabilities of surface temperature
trends (gray shading) overlaid with the observed surface temperature
trend from the Climate Research Unit (blue line) (data through
September 2010).
An additional and important discrepancy between the models and
reality extends into the lower atmosphere as well. In the lower
atmosphere, climate models expectations are that the degree of warming
with increasing greenhouse gas concentrations should be greater than
that experienced at the surface, with the lower atmosphere warming
about 1.4 times faster than the average surface temperature. Despite
claims that observations and models are in agreement (Santer et al.,
2008), new analyses incorporating a large number of both observational
datasets as well as climate model projections, clearly and strongly
demonstrate that the surface warming (which itself is below the model
mean) is significantly outpacing the warming in the lower atmosphere--
contrary to climate model expectations. Instead of exhibiting 40% more
warming than the surface, the lower atmosphere is warming 25% less--a
statistically significant difference (Christy et al., 2010).
And further, the climate models are faring little better with
oceanic temperature changes. There again, they project far more warming
than has been observed. In a much-publicized paper published in Nature
magazine in 2006 (by authors Gleckler, Wigley, Santer, Gregory,
AchutaRao, Taylor, 2006), it was claimed that by including the cooling
influence of a string of large volcanic eruptions starting in 1880,
that climate models produced a much closer match to observed trends in
ocean warming than when the models did not include the volcanic
impacts. Further, it was claimed that volcanic eruptions as far back as
Krakatoa in 1883 were still significantly offsetting warming from human
greenhouse gas emissions. However, a soon-to-be-published paper by one
of the Nature paper's original authors, Jonathan Gregory, shows that
the influence of volcanoes was greatly exaggerated as the original
climate models assumed that no major volcanic eruptions had occurred
prior to Krakatoa. In fact, episodic major eruptions are an integral
part of the earth's natural climate. Gregory shows that had climate
models been equilibrated with more realistic natural conditions, that
the long-term impact of volcanoes since the late 19th century would be
greatly minimized. In that case, the apparent match between model
simulations and observations of oceanic heat content that was noted by
Gleckler et al. would deteriorate, leaving climate models once again
over-responsive to rising levels of greenhouse gases.
I caution you that analyses of climate models can be highly
dependent upon the time period chosen. There was a major El Nino event
in 1998, which is the warmest year in the instrumental histories. Thus
any analysis beginning in this year will show little warming. On the
other hand, if one studies the last twenty years, there is a major
volcano at the beginning of the record (Pinatubo in 1991), so any
analysis beginning then will show anomalously large warming trends.
An example of the time dependency of model validation can be seen
in one of the most famous papers ever published on this subject, by
Santer et al. (1996). It was clearly rushed to print by Nature magazine
in order to provide a scientific justification for the Second
Conference of the Parties to the United Nations Framework Convention on
Climate Change, held in Geneva a mere few days after its publication.
The findings were reported in virtually every major newspaper on the
planet in this politically sensitive timeframe.
The analysis shows a remarkable fit between the observed three-
dimensional changes in the atmosphere and what was projected by models
between 1963 and 1987. But, indeed, this three-dimensional history
actually begins in 1957, and, for the purposes of this paper, clearly
ends in 1995, not 1987.
The major match for this record results from the substantial
warming of the southern hemisphere compared to the northern (Figure 3).
Indeed the time evolution of southern hot spot is striking from 1963
through 1987. But, when all of the data are used, the warming trend
completely disappears.\1\
---------------------------------------------------------------------------
\1\ The attitude displayed in the famous ``climategate'' emails has
a long provenance. This finding was shown in an invited presentation to
the American Meteorological Society annual meeting in 1997. A scientist
whom I had held in high esteem, Tim Barnett of Scripps Institute of
Oceanography, in the discussion after its presentation, threatened to
asphyxiate me with the microphone cord ``if I ever gave it again''.
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Figure 3. Modeled (upper left) and observed (upper right) temperatures
changes throughout the atmosphere. Time series of temperatures in the
region of the highlighted box in the upper right panel, 1957-1995.
Filled circles: 1963-1987; Open circles, 1957-62 and 1988-95. Use of
---------------------------------------------------------------------------
all the available data clearly changes the result.
Nonetheless, the Geneva conference marked the turning point in
international climate change policy. It was agreed there that at the
next conference, in Kyoto, that the nations of the world would adopt a
binding protocol to reduce carbon dioxide emissions. The resultant
Kyoto protocol demonstrably did nothing about climate change and was an
historic, expensive failure that led to the ultimate failure in
subsequent policy that took place in Copenhagen last December.
Testimony Objective #2: The Finding of Endangerment from greenhouse
gases by the Environmental Protection Agency is
based upon a very dubious and critical assumption
The reluctance of the Senate to mandate significant reductions in
carbon dioxide emissions has resulted in EPA taking the lead in this
activity. Consequently it issued an ``endangerment finding'' on
December 7, 2009. The key statement in this Finding is adapted from the
Fourth Assessment Report of the IPCC and from the CCSP:
Most of the observed increase in global average temperatures
since the mid-20th century is very likely due to the observed
increase in anthropogenic GHG [greenhouse gas] concentrations.
[italics added]
Here the EPA gives us a very testable hypothesis. ``Most'' means
more than 50%. ``Very likely'', according to the IPCC and CCSP, means
with a subjective probability of between 90 and 95 %. ``Since the mid-
20th century'' means after 1950. So, is more than half of the warming
since 1950 a result of ``the observed increase in anthropogenic GHG
concentrations?''
Figure 4 is a plot of observed global surface temperature since
1950 from the Climate Research Unit of the University of East Anglia.
Note that its linear behavior is quite striking, with a warming trend
of 0.70+C.
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Figure 4. Annual global average temperature history from 1950 to 2009
(source: U.K. Hadley Center).
Thompson et al., writing in Nature in 2008, noted that sea-surface
temperatures were measured too cold between the mid-1940s and mid-
1960s. Accounting for this lowers the surface warming trend from 0.70
to 0.55+C; see Figure 5.
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Figure 5. Annual global average temperature history from 1950 to 2009
(source: U.K. Hadley Center) and adjusted annual global average
temperature to remove SST errors (Thompson et al., 2008).
Late in 2007, Ross McKitrick and I published an analysis of ``non
climatic'' trends in surface temperature data. While the global effect
was not as large as some erroneous reports have stated, we found that
approximately .08+C of the warming trend was a result of these factors.
We were looking at effects that could only occur over land, and
Thompson et al. was concerned with the ocean, so these two adjustments
are obviously independent, additive, and not from GHG changes. The
remaining warming is now 0.47+C (Figure 6).
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Figure 6. Annual global average temperature history from 1950 to 2009
(source: U.K. Hadley Center) and adjusted annual global average
temperature to remove SST errors (Thompson et al., 2008) and non-
climatic influences (McKitrick and Michaels, 2007).
In January, 2010, in an attempt to explain the lack of significant
warming that has been observed since 1996, Susan Solomon published a
new simulation in Science that took into effect the radiative
consequences of changing water vapor in the stratosphere. No one really
knows why this is happening, but it is not an obvious consequence of
changing GHG concentrations. This additional factor drops the warming
to 0.41+C; see Figure 7.
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Figure 7. Annual global average temperature history from 1950 to 2009
(source: U.K. Hadley Center) and adjusted annual global average
temperature to remove SST errors (Thompson et al., 2008), non-climatic
influences (McKitrick and Michaels, 2007) and the influence of
stratospheric water vapor increases (Solomon et al., 2010).
In 2009, Ramanathan and Carmichael reviewed the effects of black
carbon--which is not a GHG--on temperature and concluded it was
responsible for approximately 25% of observed warming. This now drops
the residual warming to a ceiling of 0.31+C, or 44% of the original
0.70+ (Figure 8). Note that this catena of results does not invoke
solar variability, as estimates of its impact on recent climate vary
widely (Scafetta, 2009).
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Figure 8. Annual global average temperature history from 1950 to 2009
(source: U.K. Hadley Center) and adjusted annual global average
temperature to remove SST errors (Thompson et al., 2008), non-climatic
influences (McKitrick and Michaels, 2007), the influence of
stratospheric water vapor increases (Solomon et al., 2010) and the
influence of black carbon aerosols (Ramanathan and Carmichael, 2009).
Consequently EPA's core statement (as well as that of the IPCC and
the CCSP), ``Most of the observed increase in global average
temperatures since the mid-20th century is very likely due to the
observed increase in anthropogenic GHG [greenhouse gas]
concentrations'', is not supported.
Testimony Objective #3: The definition of science as a public good
induces certain biases that substantially devalue
efforts to synthesize science, such as those
undertaken by the IPCC and the U.S. Climate Change
Science Program (CCSP).
Visitors to the website of Scientific American have been invited to
participate in an ongoing survey on global warming. This survey finds--
despite the general environmentalist bent of its readership--that only
a tiny minority (16%) agree that the IPCC is ``an effective group of
government representatives, scientists, and other experts''. 84% agree,
however, that it is ``a corrupt organization, prone to groupthink, with
a political agenda'' (Figure 9). The concordance between the IPCC and
the bizarre one-sidedness of the CCSP Synthesis would compel the
respondents to say the same about it, if asked.
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Figure 9. Only a tiny minority of respondents (16%) agree that the IPCC
is ``an effective group of government representatives, scientists, and
other experts''. 84% agree, however, that it is ``a corrupt
organization, prone to groupthink, with a political agenda'' (Questions
4 from a Scientific American on-line poll, downloaded November 12,
2010).
This stems from the very nature of modern science, which is treated
largely as a public good, to be funded by taxpayer dollars. But, like
other tax-supported entities, science also competes within itself for
attention to its disciplines and problems. In the environment of
Washington, the most emergent or apparently urgent subjects receive
proportional public largesse. With regard to incentives, no scientific
community ever came into this House of Representatives and claimed that
its area of interest was overemphasized and that funding should be
directed elsewhere. This is normal behavior.
However, an implication of this behavior is that the peer-review
process is also populated by a community of incentivized individuals.
The test of this hypothesis would be in fact if that literature were
demonstrably biased.
Rather than use the inflammatory subject of climate change as an
example, I draw your attention to the everyday weather forecast. In the
US, we recast our global forecasting models twice a day, based upon
three dimensional measurements of atmospheric state variables that
simultaneously updated.
If the initial forecast model is unbiased, each new pieced of
information has an equal probability of either raising or lowering the
high temperature forecast three days from now. And, indeed, that turns
out to be the case.
The same should apply to climate science if there is no
incentivized bias. In fact, the ``mainstream'' community of climate
scientists claims this is true. In their Amicus brief in Massachusetts
v EPA, the supreme court case that required the EPA to determine
whether or not carbon dioxide caused ``endangerment'', Battisti et al.,
writing as ``The Climate Scientists'' state:
Outcomes may turn out better than our best current prediction,
but it is just as possible that environmental and health
damages will be more than severe than the best predictions.
As with the EPA's use of ``most'' and ``mid-20th century'', ``just
as possible'' is a quantitatively testable hypothesis. In this case,
``The Climate Scientists'' are stating that there is an equal
probability that a new scientific finding in global warming, in amount
or consequence makes future prospects either worse than previously
thought or not as bad.
I examined 13 consecutive months of Nature and Science to test the
hypothesis of unbias. Over a hundred articles were examined. Of those
that demonstrably had a ``worse than'' or ``not as bad as'' component,
over 80 were in the ``worse'' category and 11 were ``not as bad''.
The possibility that this did not reflect bias can be determined
with a binomial probability. It is similar to the likelihood that a
coin could be tossed 93 times with only 11 ``heads'' or ``tails''. That
probability is less than 1 in 100,000,000,000,000,000.
In fact, climate science holds itself apart from other quantitative
fields. Both economics and biomedical science acknowledge this problem,
known as ``publication bias'' when doing meta-analyses. It a concept is
completely foreign to the dominant mainstream in my profession, in the
IPCC and in the CCSP.
Testimony Objective #4: There is substantial discontent with
governmental and intergovernmental syntheses of
climate change and with policies passed by this
House of Representatives.
In response to a perceived political need for mandated reductions
to demonstrate our national resolve at Copenhagen, this House passed a
cap-and-trade bill on June 26, 2009. The Senate never considered such
legislation and it will rest when this Congress adjourns.
The survey by Scientific American shows the unpopularity of this
approach. Figure 10 shows that only 7.5% of nearly 7,000 respondents
say cap and trade was the course that should have been taken.
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Figure 10. Only 7.5% of nearly 7,000 respondents said cap and trade
was the course that should have been taken (Questions 7 from a
Scientific American on-line poll, downloaded November 12, 2010).
Conclusion
I hope to have demonstrated in this testimony that observed warming
rates are certainly below the mean of the most likely suite of climate
models, and that the finding of endangerment by the EPA is based upon
an important assumption that may not be true.
Further, science and scientists are demonstrably incentivized, as
publicly funded goods, in ways that make any synthesis of the
scientific literature highly susceptible to bias. Finally, an ongoing
survey by Scientific American reveals profound distrust of scientific
institutions such as the IPCC, and by extension, the CCSP, probably
caused by the incentives noted above.
References:
Battisti, D., et al., 2006. Brief of the Amici Curiae Climate
Scientists David Battisti et al. Supreme Court of the United
States, case 05-1120. 30pp.
Christy, J. R., et al. 2010. What do observational datasets say about
modeled tropospheric temperature trends since 1979? Remote
Sensing, 2, 2148-2169, doi:10.3390/rs2092148.
Gleckler, P. J., T. M. L. Wigley, B. D. Santer, J. M. Gregory, K.
AchutaRao, and K. E. Taylor, 2006. Krakatoa's signature
persists in the ocean. Nature, 439, 675, doi:10.1038/439675a.
Gregory, J. M., 2010. The long-term effect of volcanic forcing on ocean
heat content. Geophysical Research Letters, in press.
Intergovernmental Panel on Climate Change, 2007. Climate Change 2007:
The Physical Basis. Solomon S., et al. (eds). Cambridge
University Press, Cambridge, U.K., 996 pp.
McKitrick, R. R., and P. J. Michaels, 2007. Quantifying the influence
of anthropogenic surface processes inhomogeneities on gridded
global climate data. Journal of Geophysical Research, 112,
D24S09, doi:10.1029/2007JD008465.
Michaels, P.J., and P. C. Knappenberger, 1996. Human effect on global
climate? Nature, 384, 522-523.
Michaels, P.J., 2008. Evidence for ``publication bias'' concerning
global warming in Science and Nature. Energy & Environment, 19,
287-301
Ramanathan V., and G. Carmichael, 2009. Global and regional climate
changes due to black carbon. Nature GeoScience, 1, 221-227.
Santer, B.D., et al., 1996. A search for human influences on the
thermal structure of the atmosphere. Nature, 382, 39-46.
Santer, B.D., et al., 2008. Consistency of modeled and observed
temperature trends in the tropical troposphere. International
Journal of Climatology. doi:10.1002/joc.1756.
Scafetta, N., 2009. Empirical analysis of the solar contribution to
global mean air surface temperature change. Journal of
Atmospheric and Solar-Terrestrial Physics, 71, 1916-1923.
Solomon, S., et al. 2010. Contributions of stratospheric water vapor to
decadal changes in the rate of global warming. Science,
published on-line January 28, 2010.
Thompson, D., et al., 2008. A large discontinuity in the mid-twentieth
century in observed global-mean surface temperature. Nature,
453, 646-649.
Biography for Patrick J. Michaels
Patrick J. Michaels is Senior Fellow in Environmental Studies at
the Cato Institute Distinguished Senior Fellow in the School of Public
Policy at George Mason University. He is a past president of the
American Association of State Climatologists and was program chair for
the Committee on Applied Climatology of the American Meteorological
Society. Michaels was also a research professor of Environmental
Sciences at University of Virginia for thirty years. Michaels was a
contributing author and is a reviewer of the United Nations
Intergovernmental Panel on Climate Change, which was awarded the Nobel
Peace Prize in 2007. His writing has been published in the major
scientific journals, including Climate Research, Climatic Change,
Geophysical Research Letters, Journal of Climate, Nature, and Science,
as well as in popular serials worldwide. He was an author of the
climate ``paper of the year'' awarded by the Association of American
Geographers in 2004. He has appeared on most of the worldwide major
media. Michaels holds A.B. and S.M. degrees in biological sciences and
plant ecology from the University of Chicago, and he received a Ph.D.
in ecological climatology from the University of Wisconsin at Madison
in 1979.
Michaels is the author of five books on climate change, the latest
of which is Climate of Extremes: Global Warming Science They Don't Want
You to Know (Cato Books, 2009).
Chairman Baird. Dr. Santer.
STATEMENT OF BENJAMIN D. SANTER, ATMOSPHERIC SCIENTIST, PROGRAM
FOR CLIMATE MODEL DIAGNOSIS AND INTERCOMPARISON, LAWRENCE
LIVERMORE NATIONAL LABORATORY
Dr. Santer. Thank you very much, Chairman Baird, for the
opportunity to talk to you here today about climate change and
have a rational discussion.
I am not going to address some of the issues that Professor
Michaels raised. I hope that I may be able to do so in the
question and answer session.
Today is November the 17th, and my dad was born 91 years
ago on November the 17th, 1919.
[The information follows:]
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This figure is from the report which was published last
year by the U.S. Global Change Program, Global Climate Change
Impacts in the United States; and what you see on the right-
hand side is a scale that shows you the change in atmospheric
CO2 levels, as Dr. Cicerone mentioned earlier,
measured worldwide. On the left-hand side, the temperature
change, this difficult estimate of the average temperature of
the planet.
And the point I want to illustrate with this is over a
human lifetime there has been a change from roughly 300 parts
per million per volume CO2 in the atmosphere to 390.
That's not a belief system. People often ask me, Dr. Santer, do
you believe in global warming? I believe in facts and evidence.
This is a fact. I think we can all agree on this.
So the question is, what did this change in atmospheric
composition do, if anything? Well, that's a difficult question
to answer. Climate change is not an either/or proposition. It's
not either all human influences or all natural influences.
Clearly, many things are happening simultaneously: massive
volcanic eruptions, changes in the Sun's energy output, human
changes in greenhouse gases, and aerosol particles. The
difficulty is separating the natural factors from the
nonnatural factors.
In the real world, of course, we can't do that. We have no
undisturbed Earth without any human intervention. But with
computer models of the climate system we can look purely at the
natural factors, and that's what you see here, and how they may
have changed over the 20th century, changes in the Sun's energy
output and volcanic aerosols.
[The information follows:]
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You use a computer model, many computer models in this
case, and what you can see is that just with natural factors
you can't explain the warming we have observed over the second
half of the 20th century. When you have put in combined human
and natural factors, you can.
Now, this isn't convincing evidence. I agree with Dr.
Lindzen on that point. He said, you know, if you just look at
global temperature alone it's difficult to make reliable
influences about causation.
And that's why, as scientists since 1979, since the first
paper on fingerprinting, we have looked beyond the global mean.
We have looked at complex patterns of climate change. And what
you see here, again from last year's Global Climate Change
Impacts in the United States report, is a model-based estimate
of the fingerprints of different factors which affect climate.
[The information follows:]
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And there are five different fingerprints up there. There
are changes in well-mixed greenhouse gases. There are changes
in sulfate aerosol particles. Both of those are human. Sulfate
aerosols are produced by the burning of fossil fuels. Then
there are changes in stratospheric and tropospheric ozone,
changes in volcanic aerosols, solar irradiance, and then the
final pattern is all factors considered together.
Now, I don't want to go into the details. The key point
here is that they are all different. And what we are doing here
is we are looking at slices of the atmosphere from the Earth's
surface right up to 20 miles, and from the North Pole to the
South Pole; and these are model-based estimates of changes in
temperature over the last 50 years of the 20th century. They
are different, and we exploit those differences in
fingerprinting to try and understand cause and effect
relationships.
As you have heard, some people still posit even today that
the Sun explains everything. That is a testable hypothesis. We
routinely look at that hypothesis. Our best understanding is,
if the Sun's energy output had slightly increased over the last
50 years, there would be more solar energy arriving at the top
of the atmosphere; we would see heating throughout the full
vertical extent of the atmosphere. We don't see that.
[The information follows:]
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The reality is that the observations look much more similar
to the top fingerprint, the signature of well-mixed greenhouse
gases. They don't look anything like the Sun explains
everything.
[The information follows:]
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Also, as Dr. Cicerone mentioned earlier, for the last 30
years we have measured with a number of different satellite
instruments the Sun's energy output in space, and we know that
there are these 11-year cycles, but there is no overall
increase in temperature in solar irradiance over the last 30
years. There is, however, an increase in temperature over the
last 30 years. So the Sun explains everything does not
convincingly explain observed climate change. It doesn't fit
the bill.
Now, back at the time when this fingerprinting work first
came to the fore, Professor Michaels mentioned that in the mid-
1990s it was criticized. Quite rightly, I believe. People said
if there really is a human-caused fingerprint in observations,
go look in many different locations, not just at the at the
surface of the Earth, not just in atmospheric temperatures. But
look in rainfall, look in moisture, look in pressure patterns.
And that's exactly what the community has done. The community
has looked in many different aspects of the climate system,
used these statistical rigorous comparisons to look at patterns
of change, not global mean numbers, and has been able to show
that the changes in all of these things are not consistent with
natural causation alone. Now, you may not like that result, but
that's our best understanding that we have. The climate system
is telling us an internally and physically consistent story.
[The prepared statement of Dr. Santer follows:]
Biography and Prepared Statement of Benjamin D. Santer
1. Biographical information
My name is Benjamin Santer. I am a climate scientist. I work at the
Program for Climate Model Diagnosis and Intercomparison (PCMDI) at
Lawrence Livermore National Laboratory (LLNL) in California. I am
testifying today as a member of Lawrence Livermore National Laboratory
and of PCMDI.
I have been employed at PCMDI since 1992. PCMDI was established in
1989 by the U.S. Department of Energy, and has been at LLNL since then.
PCMDI's mission is to quantify how well computer models simulate
important aspects of present-day and historical climate, and to reduce
uncertainties in model projections of future climate change.
PCMDI is not engaged in developing its own computer model of the
climate system (``climate model ''). Instead, we study the performance
of all the world's major climate models. We also coordinate
international climate modeling simulations, and help the entire climate
science community to analyze and evaluate climate models.
I have a Ph.D. in Climatology from the Climatic Research Unit of
the University of East Anglia in the United Kingdom. I went to the
Climatic Research Unit in 1983 because it was (and still is) one of the
world's premier institutions for studying past, present, and future
climate. During the course of my Ph.D., I was privileged to work
together with exceptional scientists--with people like Tom Wigley, Phil
Jones, Keith Briffa, and Sarah Raper.
My thesis explored the use of so-called ``Monte Carlo'' methods in
assessing the quality of different climate models. After completing my
Ph.D. in 1987, I spent five years at the MaxPlanck Institute for
Meteorology in Hamburg, Germany. During my time in Hamburg, I worked
with Professor Klaus Hasselmann on the development and application of
``fingerprint'' methods, which are valuable tools for improving our
understanding of the nature and causes of climate change.
Much of the following testimony is adapted from a chapter Tom
Wigley and I recently published in a book edited by the late Professor
Stephen Schneider (1), and from previous testimony I gave to the House
Select Committee on Energy Independence and Global Warming (2).
2. Introduction
In 1988, the Intergovernmental Panel on Climate Change (IPCC) was
jointly established by the World Meteorological Organization and the
United Nations Environment Programme. The goals of this panel were
threefold: to assess available scientific information on climate
change, to evaluate the environmental and societal impacts of climate
change, and to formulate response strategies. The IPCC's first major
scientific assessment, published in 1990, concluded that ``unequivocal
detection of the enhanced greenhouse effect from observations is not
likely for a decade or more'' (3).
In 1996, the IPCC's second scientific assessment made a more
definitive statement regarding human impacts on climate, and concluded
that ``the balance of evidence suggests a discernible human influence
on global climate'' (4). This cautious sentence marked a paradigm shift
in our scientific understanding of the causes of recent climate change.
The shift arose for a variety of reasons. Chief amongst these was the
realization that the cooling effects of sulfate aerosol particles
(which are produced by burning fossil fuels that contain sulfates) had
partially masked the warming signal arising from increasing atmospheric
concentrations of greenhouse gases (5).
A further major area of progress was the increasing use of
``fingerprint'' studies (6, 7, 8). The strategy in this type of
research is to search for a ``fingerprint'' (the climate change pattern
predicted by a computer model) in observed climate records. The
underlying assumption in fingerprinting is that each ``forcing'' of
climate--such as changes in the Sun's energy output, volcanic dust,
sulfate aerosols, or greenhouse gas concentrations--has a unique
pattern of climate response (see Figure 1). Fingerprint studies apply
signal processing techniques very similar to those used in electrical
engineering (6). They allow researchers to make rigorous tests of
competing hypotheses regarding the causes of recent climate change.
The third IPCC assessment was published in 2001, and went one step
further than its predecessor. The third assessment reported on the
magnitude of the human effect on climate. It found that ``There is new
and stronger evidence that most of the warming observed over the last
50 years is attributable to human activities'' (9). This conclusion was
based on improved estimates of natural climate variability, better
reconstructions of temperature fluctuations over the last millennium,
continued warming of the climate system, refinements in fingerprint
methods, and the use of results from more (and improved) climate
models, driven by more accurate and complete estimates of the human and
natural ``forcings'' of climate.
This gradual strengthening of scientific confidence in the reality
of human influences on global climate continued in the IPCC AR4 report,
which stated that ``warming of the climate system is unequivocal'', and
that ``most of the observed increase in global average temperatures
since the mid-20th century is very likely due to the observed increase
in anthropogenic greenhouse gas concentrations'' (10) (where ``very
likely'' signified >90% probability that the statement is correct). The
AR4 report justified this increase in scientific confidence on the
basis of ``. . . longer and improved records, an expanded range of
observations and improvements in the simulation of many aspects of
climate and its variability'' (10). In its contribution to the AR4,
IPCC Working Group II concluded that anthropogenic warming has had a
discernible influence not only on the physical climate system, but also
on a wide range of biological systems which respond to climate (11).
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Figure 1: Climate simulations of the vertical profile of temperature
change due to five different factors, and the effect due to all factors
taken together. The panels above represent a cross-section of the
atmosphere from the North Pole to the South Pole, and from the surface
up into the stratosphere. The black lines show the approximate location
of the tropopause, the boundary between the lower atmosphere (the
troposphere) and the stratosphere. This Figure is reproduced from Karl
et al. (12).
Extraordinary claims require extraordinary proof (13). The IPCC's
extraordinary claim that human activities significantly altered both
the chemical composition of Earth's atmosphere and the climate system
has received extraordinary scrutiny. This claim has been independently
corroborated by the U.S. National Academy of Sciences (14), the Science
Academies of eleven nations (15), and the Synthesis and Assessment
Products of the U.S. Climate Change Science Plan (16). Many of our
professional scientific organizations have also affirmed the reality of
a human influence on global climate (17).
Despite the overwhelming evidence of pronounced anthropogenic
effects on climate, important uncertainties remain in our ability to
quantify the human influence. The experiment that we are performing
with the Earth's atmosphere lacks a suitable control: we do not have a
convenient ``undisturbed Earth'', which would provide a reference
against which we could measure the anthropogenic contribution to
climate change. We must therefore rely on numerical models and
paleoclimate evidence (18, 19, 20) to estimate how the Earth's climate
might have evolved in the absence of any human intervention. Such
sources of information will always have significant uncertainties.
In the following testimony, I provide a personal perspective on
recent developments in the field of detection and attribution (``D&A'')
research. Such research is directed towards detecting significant
climate change, and then attributing some portion of the detected
change to a specific cause or causes (21, 22, 23, 24). I also make some
brief remarks about openness and data sharing in the climate modeling
community, and accommodation of ``alternative'' views in the IPCC.
3. Recent Progress in Detection and Attribution Research
Fingerprinting
The IPCC and National Academy findings that human activities are
affecting global-scale climate are based on multiple lines of evidence:
1. Our continually-improving physical understanding of the
climate system, and of the human and natural factors that cause
climate to change;
2. Evidence from paleoclimate reconstructions, which enables
us to place the warming of the 20th century in a longer-term
context (25, 26);
3. The qualitative consistency between observed changes in
different aspects of the climate system and model predictions
of the changes that should be occurring in response to human
influences (10, 27);
4. Evidence from rigorous quantitative fingerprint studies,
which compare observed patterns of climate change with results
from computer model simulations.
Most of my testimony will focus on the fingerprint evidence, since
this is within my own area of scientific expertise.
As noted above, fingerprint studies search for some pattern of
climate change (the ``fingerprint'') in observational data. The
fingerprint can be estimated in different ways, but is typically
obtained from a computer model experiment in which one or more human
factors are varied according to the best-available estimates of their
historical changes. Different statistical techniques are then applied
to quantify the level of agreement between the fingerprint and
observations and between the fingerprint and estimates of the natural
internal variability of climate. This enables researchers to make
rigorous tests of competing hypotheses (28) regarding the possible
causes of recent climate change (21, 22, 23, 24).
While early fingerprint work dealt almost exclusively with changes
in near-surface or atmospheric temperature, more recent studies have
applied fingerprint methods to a range of different variables, such as
changes in ocean heat content (29, 30), Atlantic salinity (31), sea-
level pressure (32), tropopause height (33), rainfall patterns (34,
35), surface humidity (36), atmospheric moisture (37, 38), continental
river runoff (39), and Arctic sea ice extent (40). The general
conclusion is that for each of these variables, natural causes alone
cannot explain the observed climate changes over the second half of the
20th century. The best statistical explanation of the observed climate
changes invariably involves a large human contribution.
These fingerprint results are robust to the processing choices made
by different groups, and show a high level of physical consistency
across different climate variables. For example, observed atmospheric
water vapor increases (41) are physically consistent with increases in
ocean heat content (42, 43) and near-surface temperature (44, 45).
There are a number of popular misconceptions about fingerprint
evidence. One misconception is that fingerprint studies consider
global-mean temperatures only, and thus provide a very poor constraint
on the relative contributions of human and natural factors to observed
changes (46). In fact, fingerprint studies rely on information about
the detailed spatial structure (and often the combined space and time
structure) of observed and simulated climate changes. Complex patterns
provide much stronger constraints on the possible contributions of
different factors to observed climate changes (47, 48, 49).
Another misconception is that computer model estimates of natural
internal climate variability (``climate noise'') are accepted
uncritically in fingerprint studies, and are never tested against
observations (50). This is demonstrably untrue. Many fingerprint
studies test whether model estimates of climate noise are realistic.
Such tests are routinely performed on year-to-year and decade-to-decade
timescales, where observational data are of sufficient length to obtain
reliable estimates of observed climate variability (51, 52, 53, 54).
Because regional-scale climate changes will determine societal
impacts, fingerprint studies are increasingly shifting their focus from
global to regional scales (55). Such regional studies face a number of
challenges. One problem is that the noise of natural internal climate
variability typically becomes larger when averaged over increasingly
finer scales (56), so that identifying regional and local climate
signals becomes more difficult.
Another problem relates to the climate ``forcings'' used in
computer model simulations of historical climate change. As scientific
attention shifts to ever smaller spatial scales, it becomes more
important to obtain reliable information about these forcings. Some
forcings are both uncertain and highly variable in space and time (57,
58). Examples include human-induced changes in land surface properties
(59) or in the concentrations of carbon-containing aerosols (60,61).
Neglect or inaccurate specification of these factors complicates D&A
studies.
Despite these problems, numerous researchers have now shown that
the climate signals of greenhouse gases and sulfate aerosols are
identifiable at continental and sub-continental scales in many
different regions around the globe (62, 63, 64, 65). Related work (66,
67) suggests that a human-caused climate signal has already emerged
from the background noise at spatial scales at or below 500 km (68),
and may be contributing to regional changes in the distributions of
plant and animal species (69).
In summarizing this section of my testimony, I note that the focus
of fingerprint research has evolved over time. Its initial emphasis was
on global-scale changes in Earth's surface temperature. Subsequent
research demonstrated that human fingerprints were identifiable in many
different aspects of the climate system--not in surface temperature
only. We are now on the verge of detecting human effects on climate at
much finer regional scales of direct relevance to policymakers, and in
variables tightly linked to climate change impacts (70, 71, 72, 73,
74).
Assessing Risks of Changes in Extreme Events
We are now capable of making informed scientific statements
regarding the influence of human activities on the likelihood of
extreme events (75, 76, 77).
As noted previously, computer models can be used to perform the
control experiment (no human effects on climate) that we cannot perform
in the real world. Using the ``unforced'' climate variability from a
multi-century control run, it is possible to determine how many times
an extreme event of a given magnitude should have been observed in the
absence of human interference. The probability of obtaining the same
extreme event is then calculated in a perturbed climate--for example,
in a model experiment with historical or future increases in greenhouse
gases, or under some specified change in mean climate (78). Comparison
of the frequencies of extremes in the control and perturbed experiments
allows climate scientists to make probabilistic statements about how
human-induced climate change may have altered the likelihood of the
extreme event (53, 78, 79). This is sometimes referred to as an
assessment of ``fractional attributable risk'' (78).
Recently, a ``fractional attributable risk'' study of the 2003
European summer heat wave concluded that ``there is a greater than 90%
chance that over half the risk of European summer temperatures
exceeding a threshold of 1.6 K is attributable to human influence on
climate'' (78).
This study (and related work) illustrates that the ``D&A''
community has moved beyond analysis of changes in the mean state of the
climate. We now apply rigorous statistical methods to the problem of
estimating how human activities may alter the probability of occurrence
extreme events. The demonstration of human culpability in changing
these risks is likely to have significant implications for the debate
on policy responses to climate change.
4. Summary of Detection and Attribution Evidence
In evaluating how well a novel has been crafted, it is important to
look at the internal consistency of the plot. Critical readers examine
whether the individual storylines are neatly woven together, and
whether the internal logic makes sense.
We can ask similar questions about the ``story'' contained in
observational records of climate change. The evidence from numerous
sources (paleoclimate data, rigorous fingerprint studies, and
qualitative comparisons of modeled and observed climate changes) shows
that the climate system is telling us an internally consistent story
about the causes of recent climate change.
Over the last century, we have observed large and coherent changes
in many different aspects of Earth's climate. The oceans and land
surface have warmed (29, 30, 42, 43, 44, 45, 80, 81). Atmospheric
moisture has increased (36, 37, 38, 41). Rainfall patterns have changed
(34, 35). Glaciers have retreated over most of the globe (82, 83, 84).
The Greenland Ice Sheet has lost some of its mass (85). Sea level has
risen (86). Snow and sea-ice extent have decreased in the Northern
Hemisphere (40, 87, 88, 89). The stratosphere has cooled (90), and
there are now reliable indications that the troposphere has warmed (16,
91, 92, 93, 94, 95, 96, 97, 98, 99, 100). The height of the tropopause
has increased (33). Individually, all of these changes are consistent
with our scientific understanding of how the climate system should be
responding to anthropogenic forcing. Collectively, this behavior is
inconsistent with the changes that we would expect to occur due to
natural variability alone.
There is now compelling scientific evidence that human activity has
had a discernible influence on global climate. However, there are still
significant uncertainties in our estimates of the size and geographical
distribution of the climate changes projected to occur over the 21st
century (10). These uncertainties make it difficult for us to assess
the magnitude of the mitigation and adaptation problem that faces us
and our descendants. The dilemma that confronts us, as citizens and
stewards of this planet, is how to act in the face of both hard
scientific evidence that our actions are altering global climate and
continuing uncertainty in the magnitude of the planetary warming that
faces us.
5. Openness and Data Sharing in the Climate Modeling Community
Recently, concerns have been expressed about ease of access to the
information produced by computer models of the climate system.
``Climate modeling'' is sometimes portrayed as a secretive endeavor.
This is not the case.
In the 1970s and 1980s, the evaluation and intercomparison of
climate models was largely a qualitative endeavor, mostly performed by
modelers themselves. It often involved purely visual examination of
maps from a single model and observations (or from several different
models). There were no standard benchmark experiments, and there was
little or no community involvement in model diagnosis. It was difficult
to track changes in model performance over time (101).
This situation changed dramatically with the start of the
Atmospheric Model Intercomparison Project (AMIP) in the early 1990s.
AMIP involved running different Atmospheric General Circulation Models
(AGCMs) with observed sea-surface temperatures and sea-ice changes over
1979 to 1988. Approximately 30 modeling groups from 10 different
countries participated in the design and diagnosis of the AGCM
simulations. Subsequent ``revisits'' of AMIP enabled the climate
community to track changes in model performance over time (102).
The next major Model Intercomparison Project (``MIP'') began in the
mid-1990s. In phase 1 of the Coupled Model Intercomparison Project
(CMIP-1), over a dozen fully-coupled Atmosphere/Ocean General
Circulation Models (A/OGCMs) were used to study the response of the
climate system to an idealized climate-change scenario--a 1% per year
(compound interest) increase in levels of atmospheric CO2
(103). The key aspect here was that each modeling group performed the
same benchmark simulation, allowing scientists to focus their attention
on the task of quantifying (and understanding) uncertainties in
computer model projections of future climate change.
AMIP and CMIP have spawned literally dozens of other international
Model Intercomparison Projects. ``MIPs'' are now a de facto standard in
the climate science community. They have allowed climate scientists to:
Identify systematic errors common to many different
models;
Track changes in model performance over time (in
individual models and collectively);
Make informed statements about the relative quality
of different models;
Quantify uncertainties in model projections of future
climate change.
Full community involvement in ``MIPs'' has led to more thorough
model diagnosis, and to improved climate models.
Perhaps the best-known model intercomparison is phase 3 of CMIP.
The CMIP-3 project was a valuable resource for the Fourth Assessment
Report (FAR) of the IPCC (10). In the course of CMIP-3, simulation
output was collected from 25 different A/OGCMs. The models used in
these simulations were from 17 modeling centers and 13 countries.
Twelve different types of simulation were performed with each model.
The simulations included so-called ``climate of the 20th century''
experiments (with estimated historical changes in greenhouse gases,
various aerosol particles, volcanic dust, solar irradiance, etc.), pre-
industrial control runs (with no changes in human or natural climate
forcings), and scenarios of future changes in greenhouse gases. All of
the simulation output was stored at LLNL's PCMDI.
At present, 35 Terabytes of CMIP-3 data are archived at PCMDI, and
nearly 1 Petabyte of model output (1 Petabyte = 1015 bytes)
has been distributed to over 4,300 users in several dozen countries.
The CMIP-3 multi-model archive has transformed the world of climate
science. As of November 2010, over 560 peer-reviewed publications used
CMIP-3 data. These publications formed the scientific backbone of the
IPCC FAR. The CMIP-3 archive provided the basis for roughly 75% of the
figures in Chapters 8-11 of the Fourth Assessment Report, and for 4 of
the 7 figures in the IPCC ``Summary for Policymakers'' (10).
The CMIP-3 database can be used by anyone, free of charge. It is
one of the most successful data-sharing models in any scientific
community--not just the climate science community.
6. Accommodation of ``alternative'' views in the IPCC
Some parties critical of the IPCC have claimed that it does not
accommodate the full range of scientific views on the subject of the
nature and causes of climate change. In my opinion, such claims are
specious. I would contend that all four previous IPCC Assessments (3,
4, 9, 10) have dealt with ``alternative viewpoints'' in a thorough and
comprehensive way. The IPCC reports have devoted extraordinary
scientific attention to a number of highly-publicized (and incorrect)
claims.
Examples include the claim that the tropical lower troposphere
cooled over the satellite era; that the water vapor feedback is zero or
negative; that variations in the Sun's energy output explain all
observed climate change. The climate science community has not
dismissed these claims out of hand. Scientists have done the research
necessary to determine whether these ``alternative viewpoints'' are
scientifically credible, and have shown that they are not.
7. Concluding Thoughts
My job is to evaluate climate models and improve our scientific
understanding of the nature and causes of climate change. I chose this
profession because of a deep and abiding curiosity about the world in
which we live. The same intellectual curiosity motivates virtually all
climate scientists I know.
As my testimony indicates, the scientific evidence is compelling.
We know, beyond a shadow of a doubt, that human activities have changed
the composition of Earth's atmosphere. And we know that these human-
caused changes in the levels of greenhouse gases make it easier for the
atmosphere to trap heat. This is simple, basic physics. While there is
legitimate debate in the scientific community about the size of the
human effect on climate, there is really no serious scientific debate
about the scientific finding that our planet warmed over the last
century, and that human activities are implicated in this warming.
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Chairman Baird. Thank you Dr. Santer.
Dr. Alley.
STATEMENT OF RICHARD B. ALLEY, EVAN PUGH PROFESSOR, DEPARTMENT
OF GEOSCIENCES AND EARTH AND ENVIRONMENTAL SYSTEMS INSTITUTE,
THE PENNSYLVANIA STATE UNIVERSITY
Dr. Alley. Yes. Thank you for the honor, Chairman Baird,
Mr. Rohrabacher. It's a pleasure to be here.
Your body has, in its wisdom, established mechanisms to
gain an assessment of the science. Because, as you know, the
lead scientists sometimes can argue about things. In fact, you
pay us to argue about things. We love arguing about things. And
so you have set up things such as the National Academy to give
you assessments that are outside of the argument and say, what
does the science say?
And if you look at the assessments, the science is now very
clear for my interests, or especially with ice as well as
climate history. And the science says that the ice is melting
almost everywhere, almost all of it consistent with warming.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
There are a few really cold places, the top of Greenland
and the frozen ocean water around Antarctica, that increasing
precipitation has still been controlling. And that is also
consistent with our understanding of the effects of warming,
and that is expected to switch to shrinkage in the fairly near
future.
So when we look at the world, what we see is ice shrinking
because it's getting warmer. And in fact you can estimate the
warming from looking at how much the ice shrinks. And that
agrees with the thermometers.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
This is the plot of melting of mountain glaciers
contributing to the global sea level rise. You will find people
that put the plummeting one there and say catastrophe, and you
will find people that look at that blue one on top that's
Norway that grew a little bit before it started shrinking, or
they look at one wiggle in that black one, which is the
Himalayas, and they say, oh, nothing's happening. If you look
at those curves, the mountain glaciers assessed taken together
are shrinking, and they are contributing to sea level rise. And
there is really no serious question about that.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Now, if we want to know what happens in the future, this is
a very complicated plot, and I hope that you don't look in any
great detail at it. This is how much warming we expect from
rising CO2. And this particular one is if you just
doubled CO2 and then let the climate come into
equilibrium how much warming. We may go way past doubled
CO2. But the blue number up there, which is a little
over five degrees Fahrenheit, is sort of the most likely. If
you could bet on one horse, you would bet on that horse.
You have heard Dr. Michaels and earlier you heard Dr.
Lindzen arguing, well, couldn't it be lower than that, down the
green arrow? And it certainly could be. That's within the realm
of scientific possibility. But the orange arrow shows that it
could be higher than that, and the red arrow shows it could be
a lot higher than that.
You have now sort of had a discussion or a debate here
between people who are giving you the blue one and people
giving you the green one. This is certainly not both sides. If
you want both sides of it, we would have to have somebody in
here who is screaming hairy panic conniption fit on the red
end. But you are hearing just one, very optimistic side--we
wish that Dr. Michaels and Dr. Lindzen were correct--against
the assessed central value.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Now, when we look at the impacts of warming we get the same
sort of story. The IPCC looked at sea level rise, and they
said, well, this century it's probably not going to be huge.
But that excludes anything weird that the ice sheets do. And we
are very nervous because the ice sheets have started doing
something weird, and they started doing it a hundred years
before we expected them to from the previous assessment. So
when you look at sea level rise, what you find is that it's
going to rise. There is virtually no way to avoid that. But
there is a big unknown.
And so if you look at what people have been planning for,
it's something. It might be a little better, a little worse, or
a lot worse. But we don't find any evidence for a lot better.
The ice sheets are already shrinking, and they are shrinking
way before we expected them to.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Now, we do not believe in any way that you could melt a
whole ice sheet in mere decades. But we are very nervous that
within decades we could get warm enough to melt a whole ice
sheet. Now, Greenland would be seven meters plus of sea level.
Antarctica is very much bigger than Greenland. The last
estimate I saw, ten percent of the world population lives
within 10 meters of sea level. So the amount of ice which is in
play is huge for people and where they live and what they do.
We don't have really reliable projections, but we do see
sea level rising and the possibility that this century we get
to a point where we are committed to very, very large rises. So
what the planning people have been doing on this is our best
estimate. It could be a little better, a little worse, or a lot
worse, where worse I mean larger impacts on people.
So, just to summarize then, it's getting warmer. That's
melting ice. This is all consistent with what we understand
about what should happen. Everything is in there. We keep
hoping that we have overestimated the impacts, it will be
better than that. But if you plot all of the unknowns, it could
be a little better, a little worse, or a lot worse.
Thank you.
[The prepared statement of Dr. Alley follows:]
Prepared Statement of Richard B. Alley
Introduction. My name is Richard Alley. I am Evan Pugh Professor of
Geosciences and Associate of the Earth and Environmental Systems
Institute at the Pennsylvania State University. I have authored over
200 refereed scientific papers, which are ``highly cited'' according to
a prominent indexing service, and I have made many hundreds of public
presentations concerning my areas of expertise. My research is
especially focused on the great ice sheets of Greenland and Antarctica,
their potential for causing major changes in sea level, the climate
records they contain, and their other interactions with the
environment; I also study mountain glaciers, and ice sheets of the
past. I have served with distinguished national and international teams
on major scientific assessment bodies, including chairing the National
Research Council's Panel on Abrupt Climate Change (report published in
2002), and serving the Intergovernmental Panel on Climate Change (IPCC)
in various ways, and the U.S. Climate Change Science Program. I had the
honor of testifying to the Subcommittee on Investigations and Oversight
of the House Committee on Science and Technology in 2007; my testimony
today updates and extends the material I presented then.
Background on Climate Change and Global Warming. Scientific
assessments such as those of the National Academy of Sciences of the
United States (e.g., National Research Council, 1975; 1979; 2001; 2006;
2008; 2010a; 2010b), the U.S. Climate Change Science Program, and the
Intergovernmental Panel on Climate Change have for decades consistently
found with increasingly high scientific confidence that human
activities are raising the concentration of CO2 and other
greenhouse gases in the atmosphere, that this has a warming effect on
the climate, that the climate is warming as expected, and that the
changes so far are small compared to those projected if humans burn
much of the fossil fuel on the planet.
The basis for expecting and understanding warming from CO2
is the fundamental physics of how energy interacts with gases in the
atmosphere. This knowledge has been available for over a century, was
greatly refined by military research after World War II, and is
directly confirmed by satellite measurements and other data (e.g.,
American Institute of Physics, 2008; Harries et al., 2001; Griggs and
Harries, 2007).
Although a great range of ideas can be found in scientific papers
and in statements by individual scientists, the scientific assessments
by bodies such as the National Academy of Sciences consider the full
range of available information. The major results brought forward are
based on multiple lines of evidence provided by different research
groups with different funding sources, and have repeatedly been tested
and confirmed. Removing the work of any scientist or small group of
scientists would still leave a strong scientific basis for the main
conclusions.
Ice Changes. There exists increasingly strong evidence for
widespread, ongoing reductions in the Earth's ice, including snow,
river and lake ice, Arctic sea ice, permafrost and seasonally frozen
ground, mountain glaciers, and the great ice sheets of Greenland and
Antarctica. The trends from warming are modified by effects of changing
precipitation and of natural variability, as I will discuss soon, so
not all ice everywhere is always shrinking. Nonetheless, warming is
important in the overall loss of ice, although changes in oceanic and
atmospheric circulation in response to natural or human causes also
have contributed and will continue to contribute to changes. The most
recent assessment by the IPCC remains relevant (Lemke et al., 2007).
Also see the assessment of the long climatic history of the Arctic by
the U.S. Climate Change Science Program (CCSP, 2009), showing that in
the past warming has led to shrinkage of Arctic ice including sea ice
and the Greenland ice sheet, and that sufficiently large warming has
removed them entirely.
The large snowfalls that closed much of Washington, D.C. last
winter are successfully explained by the accidental ``weather'' of El
Nino and the North Atlantic Oscillation (Seager et al., 2010), and do
not undermine our understanding of the long-term effects of warming on
snow and ice. The existence of such variability virtually guarantees
that any climate record will be ``bumpy'', but scientific techniques
successfully identify the long-term trends in such bumpy records.
For sea ice (frozen ocean water), the trends in Arctic sea-ice area
and volume have been strongly downward. The reports of the National
Snow and Ice Data Center (a research institute at the University of
Colorado with funding from NSF, NASA, and NOAA) provide up-to-date
data; also see Kwok and Rothrock (2009) among many other studies. Note
that the observed shrinkage of Arctic sea ice with warming is
consistent with (although somewhat faster than) expectations from a
great range of climate models. The models generally project shrinkage
of Antarctic sea ice once warming becomes notably larger, but for the
warming to date some models have projected growth of Antarctic sea ice
in response to changing winds and ocean conditions in the very cold
Antarctic winter including freshening of the surface waters from
increasing precipitation and shrinkage of the land ice, consistent with
observations (e.g., Manabe et al., 1992; Turner et al., 2009; Liu and
Curry, 2010).
Glaciers and ice caps occur primarily in mountainous areas, and
near but distinct from the Greenland and Antarctic ice sheets. On
average, the world's glaciers were not changing much around 1960 but
have lost mass since, generally with faster mass loss more recently.
Glacier melting contributed almost an inch to sea-level rise during
1961-2003 (about 0.50 mm/year, and a faster rate of 0.88 mm/year during
1993-2003). Glaciers experience numerous intriguing ice-flow processes
(surges, kinematic waves, tidewater instabilities), allowing a single
glacier over a short time to behave in ways that are not controlled by
climate. Care is thus required when interpreting the behavior of a
particular iconic glacier (and especially the coldest tropical
glaciers, which interact with the atmosphere somewhat differently from
the great majority of glaciers). But, ice-flow processes and regional
effects average out if enough glaciers are studied for a long enough
time, allowing glaciers to be quite good indicators of climate change.
Furthermore, for a typical mountain glacier, a small warming will
increase the mass loss by melting roughly 5 times more than the
increase in precipitation from the ability of the warmer air to hold
more moisture. Thus, glaciers respond primarily to temperature changes
during the summer melt season. Indeed, the observed shrinkage of
glaciers, contributing to sea-level rise, has occurred despite a
general increase in wintertime snowfall in many places (Lemke et al.,
2007). An erroneous paragraph about Himalayan Glaciers in the IPCC
assessment from Working Group II in 2007 was identified by a
distinguished scientific team with ties to the IPCC (Cogley et al.,
2010), and this in no way changes the reality that strong glacier
melting has been occurring, with more warming expected to cause more
melting (Meehl et al., 2007).
Ice-sheet changes. The large ice sheets of Greenland and Antarctica
are of special interest, because they are so big and thus could affect
sea level so much. Melting of all of the world's mountain glaciers and
small ice caps might raise sea level by about 1 foot (0.3 m), but
melting of the great ice sheets would raise sea level by just over 200
feet (more than 60 m). We do not expect to see melting of most of that
ice, but even a relatively small change in the ice sheets could matter
to the world's coasts; roughly 10% of the world's population lives
within 10 m of sea level (McGranahan et al., 2007).
Data collected recently show that the ice sheets very likely have
been shrinking and contributing to sea level rise over 1993-2003 and
with even larger loss by 2005 and more recently, as noted in the IPCC
report and updated elsewhere (e.g., Allison et al., 2009). Thickening
in central Greenland from increased snowfall has been more than offset
by increased melting in coastal regions. Many of the fast-moving ice
streams that drain Greenland and parts of Antarctica have accelerated,
transferring mass to the ocean and further contributing to sea-level
rise.
Measurements of mass loss from the ice sheets rely on multiple
techniques, implemented by multiple groups. Techniques include
repeatedly ``weighing'' the ice sheets using the GRACE gravity
satellites, measuring changes in surface elevation using radar or laser
altimeters from satellite or aircraft, and comparing snow delivered to
the ice sheets (estimated from measurements on the ice or from
atmospheric models) to loss of ice by melting or flow into the ocean;
the results are checked against changes in the ocean level (together
with estimates of sea-level rise from other sources) and against
changes in Earth's rotation caused by the water moving from ice sheets
into the ocean (e.g., Allison et al., 2009; Cazenave et al., 2009;
Lemke et al., 2007). To date, sea-level rise has been controlled more
by mountain-glacier melting and expansion of ocean water as it warms,
but ice sheets have the greatest potential to increase their
contribution in the future.
Ice-sheet behavior. An ice-sheet is a two-mile-thick, continent-
wide pile of snow that has been squeezed to ice under the weight of
more snowfall. All piles tend to spread under their own weight,
restrained by their own strength (which is why spilled coffee spreads
on a table top but the stronger table beneath does not spread), by
friction beneath (so pancake batter spreads faster on a greased griddle
than on a dry waffle iron), or by ``buttressing'' from the sides (so a
spatula will slow the spreading of the pancake batter). Observations in
Greenland have shown that meltwater on top of the ice sheet flows
through the ice to the bottom and reduces friction there. More melting
in the future thus may reduce friction further, speeding the production
of icebergs or exposing more ice to melting from warmth at low
altitude, and thus speeding the increase in sea level (Parizek and
Alley, 2004).
Some early gothic cathedrals suffered from the ``spreading-pile''
problem, in which the sides tended to bulge out while the roof sagged
down, with potentially unpleasant consequences. The beautiful solution
was the flying buttress, which transfers some of the spreading tendency
to the strong earth beyond the cathedral. Ice sheets also have flying
buttresses, called ice shelves. The ice reaching the ocean usually does
not immediately break off to form icebergs, but remains attached to the
ice sheet while spreading over the ocean. The friction of these ice
shelves with local high spots in the sea floor, or with the sides of
embayments, helps restrain the spreading of the ice sheet much as a
flying buttress supports a cathedral. The ice shelves are at the
melting point where they contact water below, and are relatively low in
elevation hence warm above. Ice shelves thus are much more easily
affected by climatic warming than are the thick, cold central regions
of ice sheets. Rapid melting or collapse of several ice shelves has
occurred recently, allowing the ``gothic cathedrals'' behind to spread
faster, contributing to sea-level rise. Many additional ice shelves
remain that have not changed notably, and these contribute to
buttressing of much more ice than was supported by those ice shelves
that experienced the large recent changes, so the potential for similar
changes contributing to sea-level rise in the future is large.
Although science has succeeded in generating useful understanding
and models of numerous aspects of the climate system, similar success
is not yet available for ice-sheet projections, for reasons that I
would be happy to explore with the committee. We do not expect ice
sheets to collapse so rapidly that they could raise sea level by meters
over decades; simple arguments point to at least centuries. However,
the IPCC (2007) is quite clear on the lack of scientific knowledge to
make confident projections of ice-sheet behavior. The changes in ice-
sheet flow that have been contributing to sea-level rise were not
projected in the 2001 assessment (see Lemke et al., 2007), part of the
reason why best-estimate projections of sea-level rise have fallen
below observations (Rahmstorf et al., 2007). For 2007, the IPCC noted
that the sea-level-rise projections provided excluded contributions
from ``future rapid dynamical changes in ice flow'' (Table SPM-3)
``because a basis in published literature is lacking'' (page SPM14), so
that it was not possible to ``provide a best estimate or an upper bound
for sea level rise'' (page SPM15). (The 2007 report also noted a
similar difficulty arising from lack of knowledge of feedbacks in the
carbon cycle, referring to the possibility that warming will cause much
release of methane and carbon dioxide from soils in the Arctic,
sediments under the sea, or elsewhere, contributing to more warming.)
In the absence of an assessed estimate of sea-level rise, various
``back-of-the-envelope'' estimates have been provided. Without in any
way representing an assessed projection, these estimates show that a
meter or more of sea-level rise this century, with additional and
probably faster rise beyond that, falls within the realistic scientific
discussion (e.g., Pfeffer et al., 2008; Vermeer and Rahmstorf, 2009).
Tipping Points, and Abrupt Climate Change. A golden retriever
leaping to the side will force a canoe to lean, but usually the canoe
will remain upright. If an ice chest slides across the seat towards the
retriever, this positive feedback will cause the canoe to lean further.
In exceptional circumstances a tipping point may be crossed, leading to
an abrupt change as the canoe dumps the dog, ice chest, and paddlers
into the water.
Much scientific and popular discussion has focused on the
possibility that human-caused climate change may force the Earth to
cross one of its tipping points. Paleoclimatic history shows clearly
that very large, rapid and widespread changes occurred repeatedly in
the past (e.g., National Research Council, 2002; CCSP, 2008). An ice-
sheet collapse, a large change in the circulation of the North Atlantic
Ocean, a rapid outburst of methane stored in sea-floor sediments, a
sudden shift in rainfall patterns, or others are possible based on
available scientific understanding (CCSP, 2008).
The available assessments, and in particular that of the U.S.
Climate Change Science Program (CCSP, 2008), do not point to a high
likelihood of triggering an abrupt climate change in the near future
that is large relative to natural variability, rapid relative to the
response of human economies, and widespread across much or all of the
globe. However, such an event cannot be ruled out entirely, and rapidly
arriving regional droughts seem more likely than the others considered,
with potentially large effects on ecosystems and economies.
Projections of warming from a given release of greenhouse gas
generally include a best estimate, the possibility of a somewhat
smaller or somewhat larger rise, and the slight possibility of a much
larger rise; because of the way feedbacks interact in the climate
system, very large changes remain possible if unlikely, and are not
balanced by an equal probability of very small changes (e.g., Meehl et
al., 2007). The possibility of an abrupt climate change gives a similar
shape to the uncertainties about damages from whatever warming occurs,
with a chance of very large impacts.
Synopsis. With high scientific confidence, human CO2 and
other greenhouse gases are having a warming influence on the climate,
and the resulting rise in temperature is contributing to changes in
much of the world's ice. Shrinkage of the large ice sheets was
unexpected to many observers but appears to be occurring, and the poor
understanding of these changes prevents reliable projections of future
sea-level rise over long times. Large, rapid changes in the ice sheets,
or in other parts of the Earth system, may be unlikely but cannot be
excluded entirely, and such an event could have very large effects.
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Biography for Richard B. Alley
Dr. Richard Alley is Evan Pugh Professor of Geosciences and
Associate of the Earth and Environmental Systems Institute at The
Pennsylvania State University, University Park, where he has worked
since 1988. He was graduated with the Ph.D. in 1987 from the University
of Wisconsin-Madison and with M.Sc. (1983) and B.Sc. (1980) degrees
from The Ohio State University-Columbus, all in Geology. Dr. Alley
teaches, and conducts research on the climatic records, flow behavior,
and sedimentary deposits of large ice sheets, to aid in prediction of
future changes in climate and sea level. His experience includes three
field seasons in Antarctica, eight in Greenland, and three in Alaska.
His awards include election to the US National Academy of Sciences, the
Tyler Prize for Environmental Achievement, the Revelle Medal of the
American Geophysical Union and the Horton Award of their Hydrology
Section and Fellowship in the Union, the Seligman Crystal of the
International Glaciological Society, the Agassiz Medal of the European
Geosciences Union Cryospheric Section, Fellowship in the American
Association for the Advancement of Science and the American Academy of
Arts and Sciences, the US Presidential Young Investigator Award, the
Public Service Award of the Geological Society of America, the
Easterbrook Award of their Quaternary Geology and Geomorphology
Division and Fellowship in the Society, the American Geological
Institute Award For Outstanding Contribution To Public Understanding of
the Geosciences, and at Penn State, the Eisenhower Teaching Award, the
Evan Pugh Professorship, the Faculty Scholar Medal in Science, and the
College of Earth and Mineral Sciences Wilson Teaching Award, Mitchell
Innovative Teaching Award and Faculty Mentoring Award. Dr. Alley has
served on a variety of advisory panels and steering committees,
including chairing the National Research Council's Panel on Abrupt
Climate Change and participating in the UN Intergovernmental Panel on
Climate Change (which was co-recipient of the 2007 Nobel Peace Prize),
and has provided requested advice to numerous government officials in
multiple administrations including a US Vice President, the President's
Science Advisor, and committees and individual members of the US Senate
and the House of Representatives. He has published over 200 refereed
papers, and is a ``highly cited'' scientist as indexed by ISI. His
popular account of climate change and ice cores, The Two-Mile Time
Machine, was chosen science book of the year by Phi Beta Kappa in 2001.
Dr. Alley is happily married with two daughters, two cats, two
bicycles, and a pair of soccer cleats.
Chairman Baird. Thank you, Dr. Alley.
Dr. Feely.
STATEMENT OF RICHARD A. FEELY, SENIOR SCIENTIST, PACIFIC MARINE
ENVIRONMENTAL LABORATORY, NATIONAL OCEANIC AND ATMOSPHERIC
ADMINISTRATION
Dr. Feely. Good morning Chairman Baird, Ranking Member
Inglis, and Members of the Subcommittee. Thank you for giving
me the opportunity to speak today about ocean acidification,
its impacts on marine life, and our economic values.
I know this issue is one that this subcommittee has the
strongest interest in; and I would like to recognize and thank
you for your bipartisan leadership in passing the seminal
legislation, the Federal Ocean Acidification Research and
Monitoring Act of 2009, that is now the driving force behind a
NOAA, interagency, and academic effort throughout this country
to understand this new phenomenon.
Fundamental changes in seawater chemistry are occurring
throughout the world's oceans. Over the past two-and-a-half
centuries, the release of carbon dioxide from the industrial,
agricultural activities has resulted in atmospheric carbon
dioxide concentrations that have increased from 280 to about
390 parts per million.
To date, the oceans absorbed about one-third of the carbon
dioxide emissions by human activities during this period. This
natural process of absorption has benefited humankind by
significantly reducing global warming in the atmosphere and
reducing some of the impacts of global warming as well.
However, decades of ocean observation and research from NOAA,
the National Science Foundation, and the Department of Energy
has shown that the daily uptake of 22 million tons of carbon
dioxide is having a significant effect on the oceans' chemistry
and biology.
When carbon dioxide reacts with seawater, chemical changes
occur that causes a decrease in seawater pH and carbonate ions.
These chemical changes are largely referred to as ``ocean
acidification'' because of the direction of change involved.
Scientists have estimated that ocean pH has fallen about .1 pH
units since the beginning of the industrial period.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
This first slide want to I show you shows the atmospheric
concentration of CO2 at the Mauna Loa site that Dr.
Charles Keeling started in 1957, and underneath it you find the
Hawaiian Ocean Time-Series data that's maintained by the
University of Hawaii under the direction of the National
Science Foundation. You can see the increase in surface ocean
CO2 is commensurate in terms of the rate of change
with the atmospheric CO2 concentration, about 1.7
parts per million per year. Underneath that is the
corresponding pH measurements from this site, and we see a .02
pH change at this site over the last decade. So you can see
from measurements alone we can see the acidification process.
Since the pH scale is like the Richter scale, it is
logarithmic. This change in pH represents a 20 percent increase
in the hydrogen ion concentration of seawater or the acidity of
seawater. Further predictions out through the end of the
century suggest that we could have a 150 percent increase in
the acidity of seawater using the IPCC business-as-usual
scenario.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Now, it's important to note that at present we are
exceeding the CO2 emission scenarios to date. Many
marine organisms that produce calcium carbonate shells and
skeletons are negatively impacted by increasing ocean
acidification and have been shown to reduce their ability to
produce their shells and skeletons. For example, in a recent
paper just published last week, coral reef biologists have
shown that acidification could compromise fertilization and
settlement of elkhorn coral. Elkhorn coral is an endangered
species, and we are causing further harm to these organisms.
These research results suggest that ocean acidification could
severely impact the ability of coral reefs to recover from any
kind of disturbances, including major storms.
Other research indicates that by the end of this century
coral reefs may erode faster than they can be rebuilt. This
could compromise the long-term viability of those particular
ecosystems that perhaps impact over a million species that
depend on coral reefs for their survival.
Ongoing research that decrease in pH may also negatively
affect commercially important fish and shellfish species is
well under way. Both crab and sea bream larvae exhibit high
mortality rates in a high CO2 world. The
calcification rates of edible mussels and Pacific oysters
decline linearly with increasing CO2 levels. Since
2006, some oyster hatcheries in the Pacific Northwest along
Washington, Oregon, and California have experienced massive
mortalities of oyster larvae in association with a combination
of factors, including the upwelling of cold, high
CO2-rich waters.
Scientists have also seen a reduced ability of some types
of marine plankton that produce calcium carbonate shells, and
these organisms are food sources for many marine species. One
type of free-swimming mollusk called the pteropod is eaten by
organisms ranging in size from all the way from krill to
whales. Pteropods are the major food source for North Pacific
salmon and are a major food for mackerel, herring, and cod.
You can see the importance of these species to our ocean
ecosystem as they rise through the food chain. The impact of
ocean acidification in our fisheries and coral reef ecosystems
could reverberate through the United States and global economy.
The United States is the third largest seafood consumer in the
world, and total consumer spending on fish and shellfish is
about $70 billion per year. Coastal and marine commercial
fisheries generate up to $35 billion per year and employ 70,000
people.
In conclusion, ocean acidification is caused by the buildup
of carbon dioxide in the atmosphere and can have significant
impacts on marine ecosystems. Ocean acidification is an
emerging scientific issue and much research is needed before
all the ecosystem responses are understood. However, to the
limit of the scientific understanding we have about this issue
right now, the potential for environmental, economic, and
societal risks are very high, hence demanding serious and
immediate attention.
Thank you for your attention, and I look forward to your
questions.
[The prepared statement of Dr. Feely follows:]
Prepared Statement of Richard A. Feely
Introduction
Chairman Baird and members of the Subcommittee, thank you for
giving me the opportunity to speak with you today on the evidence of
climate change and ocean acidification. My name is Richard Feely. I am
a Senior Scientist at the Pacific Marine Environmental Laboratory of
the National Oceanic and Atmospheric Administration (NOAA) in Seattle,
WA. My personal area of research is the study of the oceanic carbon
cycle and ocean acidification processes. I have worked for NOAA for 36
years and have published more than 300 peer-reviewed scientific journal
articles, book chapters and technical reports. I serve on the U.S.
Ocean Carbon and Biogeochemistry Scientific Steering Committee and I am
the co-chair of the U.S. Repeat Hydrography Program Scientific
Oversight Committee. I am also a member of the International Scientific
Advisory Panel for the European Program on Ocean Acidification and the
Interagency Working Group on Ocean Acidification, under the Joint
Subcommittee on Science and Technology. Today I will discuss observed
ocean acidification, its impacts on marine life, and potential economic
impacts.
What is Ocean Acidification?
Over the past two and a half centuries, the release of carbon
dioxide (CO2) from our collective industrial and
agricultural activities has resulted in atmospheric CO2
concentrations that have increased from about 280 parts per million
(ppm) to 392 ppm. The atmospheric concentration of CO2 is
now higher than experienced on Earth for at least the last 800,000
years, and is expected to continue to rise, leading to significant
temperature increases in the atmosphere and oceans by the end of this
century. To this day, the oceans have absorbed more than 500 billion
tons of carbon dioxide from the atmosphere, equivalent to about one
third of the anthropogenic CO2 emissions released during
this period (Sabine and Feely, 2007). This natural process of
absorption has benefited humankind by significantly reducing the
greenhouse gas levels in the atmosphere and reducing the magnitude of
global warming experienced thus far.
Unfortunately the ocean's daily uptake of 22 million tons of
CO2 is having a significant impact on the chemistry and
biology of the oceans. Over the last three decades, NOAA, the National
Science Foundation and the Department of Energy have co-sponsored
repeat hydrographic and chemical surveys of the world's oceans,
documenting their response to increasing amounts of carbon dioxide
being emitted to the atmosphere by human activities. These surveys have
confirmed the oceans are absorbing increasing amounts of carbon
dioxide. Both the hydrographic surveys and modeling studies reveal that
chemical changes in seawater resulting from absorption of carbon
dioxide are increasing the acidity of seawater or lowering of its pH. A
drop in pH indicates an increase in acidity, as on the pH scale 7.0 is
neutral, with points lower on the scale being ``acidic'' and points
higher on the scale being ``basic'' (Raven et al, 2005; Feely et al.,
2009). Scientists have estimated that the pH of our ocean surface
waters has already fallen by about 0.1 units from an average of about
8.2 to 8.1 since the beginning of the industrial revolution. Because
the pH scale, like the Richter scale, is logarithmic, a 0.1 unit
decrease represents approximately a 26 percent increase in acidity.
Future predictions indicate that the oceans will continue to absorb
carbon dioxide and become even more acidic. (Feely et al., 2004; On et
al., 2005; Caldeira and Wickett, 2005; Doney et al., 2009a; Feely et
al., 2009). The United Nation's Intergovernmental Panel on Climate
Change emission scenarios and numerical circulation models indicate
that by the middle of this century, future atmospheric carbon dioxide
levels could reach more than 500 ppm, and near the end of the century
they could be as much as 700-800 ppm (On et al., 2005). This would
result in a surface water pH decrease of approximately 0.3 pH units as
the ocean becomes more acidic, which is equivalent to a doubling of
acidity. To put this in historical perspective, the resulting surface
ocean pH would be lower than it has been for at least the last 20
million years (Feely et al., 2004). When CO2 reacts with
seawater, fundamental chemical changes occur that cause seawater to
become more acidic. The interaction between CO2 and seawater
also reduces the availability of carbonate ions, which play an
important role in shell formation for a number of marine organisms such
as corals, marine plankton, and shellfish. This phenomenon, which is
commonly called ``ocean acidification,'' could affect some of the most
fundamental biological and geochemical processes of the sea in coming
decades. This rapidly emerging issue has created serious concerns
across the scientific and marine resource management communities.
Evidence of Ocean Acidification Effects on Coral Reefs
Many marine organisms that produce calcium carbonate shells are
negatively impacted by increasing carbon dioxide levels in seawater
(and the resultant decline in pH). For example, increasing ocean
acidification has been shown to significantly reduce the ability of
reef-building corals to produce their skeletons, affecting growth of
individual corals and making the reef more vulnerable to erosion
(Kleypas et al., 2006; Doney et al., 2009a; Cohen and Holcomb, 2009).
Some estimates indicate that, by the end of this century, coral reefs
may erode faster than they can be rebuilt. This could compromise the
long-term viability of these ecosystems and perhaps impact the
thousands of species that depend on the reef habitat. Decreased
calcification may also compromise the fitness or success of these
organisms and could shift the competitive advantage towards organisms
that are not dependent on calcium carbonate. Carbonate structures are
likely to be weaker and more susceptible to dissolution and erosion in
a more acidic environment. Furthermore, recent findings suggest that
the calcium carbonate cementation that serves to bind the reef
framework together may be eroded (Manzello et al., 2008). Such effects
could compromise reef resiliency in the face of other threats, such as
thermal stress, diseases, storms, and rising sea level (e.g., Silverman
et al., 2009). For example, in CO2-enriched waters around
the Galapagos Islands, reef structures were completely eroded to rubble
and sand in less than 10 years following an acute warming disturbance
(1982-83 El Nino event; Manzello et al., 2008). In long-term laboratory
and mesocosm experiments, or contained laboratory model ecosystems
under controlled conditions, corals that have been grown under lower pH
conditions for periods longer than one year have not shown any ability
to adapt their calcification rates to the lower pH levels. In fact, two
studies showed that the projected increase in CO2 is
sufficient to dissolve the calcium carbonate skeletons of some coral
species (Fine and Tchernov, 2007; Hall-Spencer et al., 2008).
Evidence of Ocean Acidification Effects on Fish and Shellfish
Ongoing research is showing that decreasing pH may also have
deleterious effects on commercially important fish and shellfish
larvae. Both king crab and silver seabream larvae exhibit very high
mortality rates in CO2-enriched waters (Ishimatsu et al.,
2004). Some of the experiments indicated that other physiological
stresses were also apparent. Exposure of some fish and shellfish to
lower pH levels can cause decreased respiration rates, changes in blood
chemistry, and changes in enzymatic activity. The calcification rates
of the edible mussel (Mytilus edulis) and Pacific oyster (Crassostrea
gigas) decline linearly with increasing CO2 levels (Gazeau
et al. 2007). Squid are especially sensitive to ocean acidification
because it directly impacts their blood oxygen transport and
respiration (Portner et al., 2005). Sea urchins raised in lower-pH
waters show evidence for inhibited growth due to their inability to
maintain internal acid base balance (Kurihara and Shirayama, 2004). The
supply of these commercially valuable species is in jeopardy from ocean
acidification.
Scientists have also seen a reduced ability of marine algae and
free-floating plants and animals to produce protective carbonate shells
(Feely et al., 2004; On et al., 2005; Doney et al., 2009b). These
organisms are important food sources for other marine species. One type
of free-swimming mollusk called a pteropod is eaten by organisms
ranging in size from tiny krill to whales. In particular, pteropods are
a major food source for North Pacific juvenile salmon, and also serve
as food for other salmon species, mackerel, pollock, herring, and cod.
Other marine calcifiers, such as coccolithophores (microscopic algae),
foraminifera (microscopic protozoans), coralline algae (benthic algae),
echinoderms (sea urchins and starfish), and mollusks (snails, clams,
and squid) also exhibit a general decline in their ability to produce
their shells with decreasing pH (Kleypas et al., 2006; Fabry et al.,
2008).
Evidence of Ocean Acidification Effects on Marine Ecosystems
Since ocean acidification research is still in its infancy, it is
impossible to predict exactly how the individual species responses will
cascade throughout the marine food chain and impact the overall
structure of marine ecosystems. It is clear, however, from both the
existing data and from the geologic record that some coral and
shellfish species will be negatively impacted in a high-CO2
ocean. The rapid disappearance of many calcifying species in past
extinction events has been attributed, in large part, to ocean
acidification events (Zachos et al., 2005; Vernon, 2008). Over the next
century, if CO2 emissions continue to increase as predicted
by the IPCC CO2 emissions scenarios, humankind may be
responsible for increasing oceanic CO2 and making the oceans
more corrosive to calcifying organisms than at anytime in the last 20
million years. Thus, the decisions that are made about carbon dioxide
emissions over the next few decades will probably have a profound
influence on the makeup of future marine ecosystems for centuries to
millennia.
Potential Economic Impacts of Ocean Acidification
The impact of ocean acidification on fisheries and coral reef
ecosystems could reverberate through the U.S. and global economy. The
U.S. is the third largest seafood consumer in the world with total
consumer spending for fish and shellfish around $70 billion per year.
Coastal and marine commercial fishing generates upwards of $35 billion
per year and employs nearly 70,000 people (NOAA Fisheries Office of
Science and Technology; http://www.st.nmfs.gov/stl/fus/fus05/
index.html). In a recent study by Cooley and Doney (2009) the total
value of U.S. commercial harvests from U.S. waters and at-sea
processing was approximately $4 billion in 2007. Almost a quarter (24%)
of all U.S. commercial harvest revenue was from harvesting fish that
prey directly on calcifying organisms. Different species dominate
different regional revenues; mollusks are more important in the New
England and mid- to south-Atlantic regions, crustaceans contribute
greatly to New England and Gulf of Mexico fisheries, and predators
dominate the Alaskan, Hawaiian, and Pacific territory fisheries. On the
west coast shellfish industries bring in more than $110 million in
revenue each year. Bivalves, such as oysters, also filter marine and
estuarine waters and create habitat for other species, serving
important ecosystem services (NOAA OA Plan, 2009; Feely et al., 2010).
Since 2006, some oyster hatcheries in the Pacific Northwest region have
experienced mass mortalities of oyster larvae in association with a
combination of factors, including unusually saline surface waters and
the upwelling of cold, CO2- and nutrient-rich waters (Feely et al.,
2008).
Healthy coral reefs are the foundation of many viable fisheries, as
well as the source of jobs and businesses related to tourism and
recreation. Increased ocean acidification may directly or indirectly
influence the fish stocks because of large-scale changes in the local
ecosystem dynamics. It may also cause the dissolution of the newly
discovered deepwater corals in the West Coast and Alaskan Aleutian
Island regions, where many commercially important fish species in this
region depend on this particular habitat for their survival. In the
Florida Keys alone, coral reefs attract more than $1.2 billion in
tourism annually (English et al., 1996). In Hawaii, reef-related
tourism and fishing generate $360 million per year, and their overall
worth has been estimated at close to $10 billion (Cesar et al., 2002).
In addition to sustaining commercial fisheries, tourism, and
recreation, coral reefs also provide vital protection to coastal areas
that are vulnerable to storm surges and tsunamis.
NOAA Ocean Acidification Research
Ocean acidification is an important new scientific frontier which
we must understand better given its potentially adverse consequences.
NOAA research activities offer significant contributions to improving
our understanding and assessing the impacts of this rapidly emerging
issue. In response to the Federal Ocean Acidification Research and
Monitoring Act of 2009 (FOARAM Act), NOAA is in the process of hiring a
permanent ocean acidification program director as a final step to the
establishment of a new NOAA ocean acidification program, per section
12406 of the FOARAM Act. NOAA has also developed an integrated Ocean
Acidification and Great Lakes research and long-term monitoring plan
for assessing climate change impacts on living marine resources and the
businesses and communities that depend on their sustainable use. The
primary goals of this plan are to:
Assess the ecological and socioeconomic effects of
ocean acidification on commercial fish species and the greater
ecosystems on which they rely;
Develop and provide sensors to monitor ocean
acidification both for fixed platforms and for mobile use by
researchers and coastal managers in the field;
Determine and monitor the status and potential
effects of ocean acidification on coral reefs and other
protected areas such as National Marine Sanctuaries; and
Expand carbonate analytical capabilities at NOAA
science centers in order to meet the growing demand for quality
control on samples being collected both in the field from U.S.
waters and from researchers studying the impacts of ocean
acidification on critical species through laboratory
experiments.
The results of this research will help to inform future strategies
to help communities, ecosystems, and industries respond to ocean
acidification. The increased research capabilities will complement,
accelerate, and enhance current NOAA ocean acidification activities
within the Office of Oceanic and Atmospheric Research, National Ocean
Service, and National Marine Fisheries Service.
Interagency Planning
The FOARAM Act directed the Joint Subcommittee on Ocean Science and
Technology (JSOST) of the National Science and Technology Council to
create an Interagency Working Group on Ocean Acidification (IWG-OA),
chaired by NOAA. The IWG-OA was charged with developing a strategic
plan for Federal research and monitoring on ocean acidification that
will provide for an assessment of the impacts of ocean acidification on
marine organisms and marine ecosystems and the development of
adaptation and mitigation strategies to conserve marine organisms and
marine ecosystems. The IWG-OA has developed a draft strategic plan that
is presently undergoing review, in preparation for delivery in early
spring 2011 as requested by the FOARAM Act.
Conclusion
In conclusion, ocean acidification is caused by the buildup of
carbon dioxide and other acidic compounds in the atmosphere and is
expected to have significant impacts on marine ecosystems. Results from
laboratory, field and modeling studies, as well as evidence from the
geological record, clearly indicate that marine ecosystems are highly
susceptible to the increases in oceanic CO2 and the
corresponding decreases in pH. Because of the very clear potential for
ocean-wide impacts of ocean acidification at all levels of the marine
ecosystem, from the tiniest phytoplankton to zooplankton to fish and
shellfish, we can expect to see significant impacts that are of immense
importance to humankind. Ocean acidification is an emerging scientific
issue and much research is needed before the breadth and magnitude of
ecosystems'' responses are well understood. However, to the limit that
the scientific community understands this issue right now, the
potential for environmental, economic and societal risk is quite high,
hence demanding serious and immediate attention. Thank you for giving
me the opportunity to address this Subcommittee. I look forward to
answering your questions.
References and Additional Sources
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Cohen, A.L., and M. Holcomb. 2009. Why corals care about ocean
acidification: Uncovering the mechanism. Oceanography
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Doney, Scott C., Victoria J. Fabry, Richard A. Feely, and Joan A.
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Biography for Richard A. Feely
Dr. Richard A. Feely is a Senior Scientist at the NOAA Pacific
Marine Environmental Laboratory in Seattle. He also holds an affiliate
full professor faculty position at the University of Washington School
of Oceanography. His major research areas are carbon cycling in the
oceans and ocean acidification processes. He received a B.A. in
chemistry from the University of St. Thomas, in St Paul, Minnesota in
1969. He then went to Texas A&M University where he received both a
M.S. degree in 1971 and a Ph.D. degree in 1974. Both of his post-
graduate degrees were in chemical oceanography. He is the co-chair of
the U.S. CLIVAR/CO2 Repeat Hydrography Program. He is also a member of
the Steering Committee for the U.S. Carbon and Biochemistry Program. He
is a member of the American Geophysical Union, the American Association
for the Advancement of Science and the Oceanography Society. Dr. Feely
has authored more than 200 refereed research publications. He was
awarded the Department of Commerce Gold Award in 2006 for research on
ocean acidification. In 2007, Dr. Feely was elected to be a Fellow of
the American Geophysical Union. He recently was awarded the Heinz Award
for his pioneering research on ocean acidification.
Discussion
Chairman Baird. Thank you, Dr. Feely. Thanks to all the
witnesses.
At this point, I will recognize myself for five minutes and
follow-up questions from my colleagues.
Ocean Acidification and Coral Damage
Dr. Feely, you focused on the evidence of ocean
acidification. It appears to be a pretty strong connection. Two
questions for you, one tangential. There has, my understanding,
been an enormous coral die-off worldwide, particularly in the
Caribbean, as we have seen coral bleaching from high sea
temperatures. Can you very briefly comment on that?
And then, secondly, are there alternative explanations that
seem credible to explain the acidification levels that you have
been measuring?
Dr. Feely. To answer your first question, because of the
increasing level of temperatures in the ocean, we have seen
coral die-offs of as much as 16 percent globally. And the
projections are that out to the end of this century we may not
see very many of the coral reefs be able to survive. That's the
dire situation we are faced with.
The concern we have in terms of the acidification is that
some of the preliminary research has shown that the combination
of increased CO2 and the increased temperature
associated with global warming enhances the bleaching impact on
those corals. So their risk of survival is even greater.
Chairman Baird. Do you want to--are there other
alternatives? What is another alternative explanation for the
measured increase in acidity or, in other words, lowered pH,
other than the CO2 hypothesis?
Dr. Feely. The major alternative suggestion is that perhaps
CO2 evolution from volcanic activity, hydrothermal
activity in the deep sea, could be enriching the CO2
levels in the surface oceans. But we have published papers on
this subject to show that the amount of CO2 from
volcanic activity in any given year is 1/100 of the amount of
CO2 that enters the atmosphere.
Chairman Baird. Thanks, Dr. Feely.
Measuring Glacial Changes
Dr. Alley, two questions. One, tell us a little bit about
how--from your graph, it looked like you feel pretty confident
that the data suggests the ice sheets, glaciers around the
world are melting, with a few exceptions. Tell us a little bit
about the methodology by which that is measured first.
And secondly, haven't there been times in the past when we
have seen receding glaciers and receding ice sheets and
comments about my goodness, things seem to be going in the
opposite direction. Glaciers--you know. And what is the
difference now?
Dr. Alley. Right. So for measuring, say, what Greenland is
doing, some of that work is done by weighing the ice sheet
using the GRACE gravity satellites, which is truly wonderful.
It is like watching cars on a roller coaster and the one going
down gets away from the one that is going up, and then the one
going down catches up. And you watch----
Chairman Baird. As I understand it, it is fascinating with
satellites sort of pursuing each other and gravitational
attraction slows one down, relative to the other. And by
measuring the rate of that different speed, you can tell how
much mass is underneath you. And as that mass declines, there
is less slowing down.
Dr. Alley. Perfect. I should retire and let you teach this.
Chairman Baird. I just think it is beautiful.
Dr. Alley. So you weigh them using GRACE, but then you
measure changes in surface elevation, is it going down or up,
using a radar or a laser from a plane or a satellite, and all
of those have been done. And then you figure out how much snow
is being added and how much melt water is leaving and how much
ice is leaving. And then you compare all of these to see if
they give the same answer. And all of them indicate shrinkage
of Greenland.
You are certainly correct that the ice has grown and shrunk
in the past. And I had the honor of serving for the United
States Government on the Climate Change Science Program on a
report of the history of the arctic. And what we found was very
clear for Greenland. When nature made it warmer, Greenland got
smaller. And when nature made it colder, Greenland got bigger.
And we are now making it warmer and Greenland is getting
smaller.
Evidence of Anthropogenic Change
Chairman Baird. How do we know it is we, not nature? I
mean, we have the increase in CO2. But the skeptic
would argue, well, wait a second, I can go back to 1927 and
find articles about glaciers retreating. What is the
difference? I mean, you know, you can look at a football team
and say they were losing back then and they are losing now, so
what is the difference?
Dr. Alley. Right. So the first one is the physics. We just
cannot get away from the warming effect of CO2. It
has been known for over a century. It was really clarified by
the Air Force who were actually interested in what wavelength
should I use for the sensor on my heat-seeking missile. But
CO2 interacts with radiation and there is enough
CO2 to make a difference. And we just can't get away
from that physics.
The second one is--is looking at is there any other
possible thing to explain this. And it really took--I am sorry,
sir, it took a few billion dollars of your money and about 30
years to say that there is nothing else that we can find in
nature to do this. And this is because satellites are
expensive.
But someone says it is the sun. Well, then you need a
satellite to watch the sun to see if the sun is getting
brighter, but it isn't. And if someone says, well, it is
volcanoes, then we need a history of volcanoes and we need to
know what they are doing. And someone says it is cosmic rays,
we need cosmic ray monitors. And it has taken sort of 30 years
to get to the point of saying, no, we have looked really hard,
we can't find anything else.
And there is a third piece, which is the fingerprinting,
which is what Dr. Santer was discussing. If you were to say,
okay, yeah, I know we spend a lot of money on satellites and
the satellites say the sun is not getting brighter, but maybe,
maybe, maybe the satellites are wrong and the sun is getting
brighter and we can't see it. That makes a prediction. It gets
warmer down here and it gets warmer way up at the top of the
stratosphere. CO2 says warm down there or colder up
there. What is going on is warmer down here and colder up
there? So the fingerprinting and time in space says that we got
it right on the other two pieces. It is mostly us now.
Chairman Baird. I want to be clear. It is not my money. It
is your money.
Dr. Alley. Thank you, sir. Absolutely.
Chairman Baird. It is the taxpayers' money. I never forget
it. But I think at the same time, if we don't address our
energy dependence and if we don't address appropriately, then
by my judgment, real impacts of this will vastly exceed a
billion dollars. And if we can make some measured changes to
reduce that impact, the savings will exceed the expenditures
by--Dr. Santer, you might want to comment, Dr. Michaels? And
then I will recognize my colleague.
Dr. Santer. Yeah. I just wanted to comment briefly on what
Dr. Alley said about the fingerprinting. We have known that
increases in CO2 have this characteristic
fingerprint of warming the lower atmosphere, the troposphere,
and cooling the upper atmosphere since about the late 1950s,
early 1960s, when people performed the first numerical model
experiments and doubled CO2. And they saw this
characteristic pattern of cooling of the stratosphere and
warming of the troposphere. Very robust. We see that in
virtually every model experiment that has been performed. And
as mentioned, we also see it in observations, too. We see it in
satellite data. We see it in weather balloon data.
Now, people often say these computer models are not
falsifiable. They make predictions that we can't test. That is
not true. Back in the 1960s, when Suki Manabe and his
colleagues at the Geophysical Fluid Dynamics Lab in Princeton
made these calculations and doubled atmospheric CO2
and saw this fingerprint, we didn't really have the
observational data to see whether the stratosphere was actually
cooling, whether the troposphere was warming. They have. The
stratosphere has cooled. The troposphere has warmed. That
fingerprint is robust and it is just not consistent with other
natural causes.
Chairman Baird. Dr. Michaels, did you care to comment on
any of this?
Dr. Michaels. I have several comments I would like to make.
It would probably take up the rest of the day. So I will just
limit--that won't happen, no, it certainly won't. I will limit
it to the notion of--what we are talking about here, you've
noticed, is everybody says that the planet has warmed up and
that people have something to do with it. So what really
matters is the magnitude of it.
If I can have the clicker, this is just going to take a
second. It is not going to be as bad as you think. There it is.
Right there. This is the warming from the IPCC--from the CRU
record from 1950. And our Environmental Protection Agency
which, as you know, has taken over the regulatory aspect of
this because of what happened in the Congress, issued an
endangerment finding on warming. And they asserted in their
endangerment finding that more than half of the warming of the
late 20th century is a result--very likely a result of human
greenhouse gases. More than half means more than 50 percent.
Late 20th century means after 1950. Do you agree with that?
Second--sorry. I said second half of the 20th century.
Well, in fact there are four different factors that are totally
independent of the greenhouse effect. One that we
overestimated--underestimated sea surface temperatures from
1944 to 1965. That was published by Thompson in Nature
Magazine. Number two, that there are nonclimatic subtle effects
on the temperature history. That was published by McKitrick in
the Journal of Geophysics Atmospheres. Susan Solomon found that
water vapor in the stratosphere is responsible for a lot of the
secular changes. And we don't know why water vapors fluctuate
in the stratosphere. It is not a greenhouse effect. I mean, it
is not--it is not, apparently, from greenhouse gas emissions.
And number four, Rominoffon at Stanford said, well, about 25
percent of the warming is a result of black carbon going in the
atmosphere. That is also not a greenhouse gas.
When you add all of those up, the warming drops from .7 to
.3 degrees. So the assertion that over half the warming is a
function of greenhouse gases is challenged by four completely
independent factors. I think we have got a lot more work to do
on this frankly.
Chairman Baird. Any very quick response to that? And then
Mr. Inglis.
Dr. Santer. Yes, might I respond to that?
Chairman Baird. Very quickly.
Dr. Michaels. Dr. Michaels' analysis is wrong. I am sorry.
It is just completely incorrect. What he has attempted to do
here is explain the observed temperature change over the last
60 years from 1950 through 2010. And he said that the estimated
total change in temperature is .7 degrees. Now, he has
identified four things--economic activity, black carbon, errors
in the sea surface temperature data and stratospheric water
vapor--and he said, I think all of those things have had a
warming influence, so I am going to subtract them from this .7
degrees and I am left with .3. Point 3 is less than half of .7,
therefore the IPCC is wrong. And the conclusion that more than
half of the observed warming over the 20th century was very
likely due to increases in greenhouse gases is one of the
central conclusions of the IPCC. So if Dr. Michaels is right,
that central conclusion is wrong.
What Dr. Michaels did not mention either here or in his
written testimony is the cooling effect of sulfate aerosols,
which has already been discussed at this hearing. If you
indulge me for a moment, I am just going to bring up one slide
here.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Now, this is a slide from a paper published in 2006 by
Peter Stott at the Hadley Center. So what you see in the bottom
are three different climate models, and it is the estimate of
their sulfate cooling caused by the scattering effects of
sulfate aerosols over the 20th century. It is negative.
Now, if you assume conservatively that that cooling effect
over 1950 to 2010 period Dr. Michaels looked at was, say, minus
.4 degrees Celsius over that 60-year period and you assume that
Dr. Michaels was completely correct in estimating the magnitude
of the four factors that he removed from the observations, you
would be adding minus .4 and plus .4. You would get to zero. So
you still need to explain .7. You need to get to the observed
total temperature change over the 60-year period.
What could that be? Could it be the sun? No way. It
couldn't be the sun. If solar effects were that large on the
60-year time scale, we could see a huge 11-year cycle in the
temperature data. We don't. Could it be volcanoes? No, it
couldn't be volcanoes. Could it be some mode of natural
variability, some internal oscillation of the climate system
that could generate that .7 degree temperature increase? Not
plausible.
The most plausible explanation is an increase in
atmospheric CO2. We know CO2 has changed.
Again, that is not some assertion. That is not supposition. We
know that. So what the IPCC found here and what they reported
on was that actually the change in temperature due to
greenhouse gases, which is what you see in red, was larger than
the actually observed change in temperature, which is that
horizontal black line. So the greenhouse gas signal was offset.
That is our best understanding by the cooling caused by these
sulfate aerosols. They scatter incoming sunlight and they also
change cloud properties.
Dr. Michaels. Excuse me. Excuse me. I beg your pardon for a
second. The IPCC gives the range of prospective forcing from
sulfate aerosol at zero, a range from zero to minus two watts
per meter square. That gives you an incredible wiggle room any
time you want to make an argument, doesn't--doesn't it now?
It is very interesting to look at sulfate aerosol in terms
of the history of science. The first book I ever read at the
University of Chicago was ``The Structure of Scientific
Revolutions'' by Thomas Kuhn. I recommend it to everyone. It
predicts that when a paradigm experiences anomalous data, then
increasingly strange explanations are brought forth.
In 1985, Tom Wigley, who was Ben's advisor, recognized in a
paper that the greenhouse gas models were producing too much
warming and invoked sulfates. And then you can tune models with
sulfates and get things to work perfectly well. Well, the fact
of the matter is that our understanding of what the radiative
effects of these things are is so wide that I can give you
virtually any answer. And So I am just assuming to leave that
alone.
Chairman Baird. I recognize Mr. Inglis.
Mr. Inglis. And I think it is worth following up on that
because--and this is why this hearing is so valuable, because
these are the kind of things that confuse people and confuse
the public a great deal. So, Dr. Santer, do you want to
continue with your--what is your retort?
Dr. Santer. Yes, if I could. Dr. Michaels was wrong again.
He claimed that the IPCC's published estimate of the radiative
effect of sulfate aerosols was zero to minus two watts per
square meter. That serves for the indirect effect. That is for
the effect of aerosols on clouds, on cloud cover and on cloud
brightness, which is very uncertain.
The IPCC's estimate of the direct scattering of effect of
aerosols, how they scatter incoming sunlight back into space,
does not intersect with zero. It is negative. And the best
estimate is an order of minus .5 watts per square meter.
The cooling effect of sulfate aerosols has been established
not only observationally and in models and theoretically. In
dozens of studies, we can see these things from space. They are
not supposition. This is not science fiction. And leaving out
this negative forcing in his testimony to you is misleading
you. I am sorry.
Dr. Michaels. The problem here is that the error bars
around these things are very, very large. And furthermore,
there is an issue with the sensitivity. Excuse me. I would like
to finish.
This discussion is really about the sensitivity of
temperature to various and sundry forcings. And there is quite
a discussion as to, in fact, what the change in temperature is
per change in watt per meter squared down while in flux. If it
is on the order of I think what Lindzen thinks it is, then the
sulfates aren't going to be all that important. So this is
just--this is an open matter for discussion. I am sorry. We
just don't know everything.
Chairman Baird. Dr. Santer.
Dr. Santer. Might I respond very quickly? I am glad that
Dr. Michaels raised the issue of uncertainties. In the
fingerprinting work that we do, we constantly look at
uncertainties. They are part and parcel of our lives. We look
at uncertainties in the fingerprints, those patterns I showed
you that arise from use of different models. We look at
uncertainties in model estimates of natural climate noise. And
we look at uncertainties in the statistical methods that we use
to compare models and observations. We spend all of our time
looking at uncertainties.
In this analysis here on Dr. Michael's slide, you will see
there are no error bars. In this subtraction exercise, no error
bars, and the temperature changes are given to within a
thousandth of a degree C.
Now, to me, again, that is just completely ignoring the
significant scientific uncertainties in this partitioning of
natural and human effects. You have to account for them. You
have to look at all effects, both positive and negative. You
can't forget sulfate aerosols. This analysis has not done that.
And anything that claims to overturn the central finding of the
IPCC's fourth assessment report should do it as thoroughly and
comprehensively as possible. This analysis fails in that
regard.
Dr. Michaels. Is that why one would use 1963 through 1987,
when there was data through 1995? Is that why one would, in
fact, begin a volcanic analysis in 1883 when the atmosphere was
loaded with volcanic junk prior to then?
Chairman Baird. I am going to intervene just a little bit.
I think for understandable reasons, people have published
different papers. And the challenge is if two individuals are
sort of in the scientific community going at it with each
other, it is an interesting and important discussion.
So I want Dr. Santer to respond to that because you
addressed it earlier, Mr. Michaels. But I don't want to
dominate. I am interrupting my colleague's time here. But I
just want to set a little bit of ground rules. We won't go on
forever with this particular debate. Is that all right with
you, Bob?
Mr. Inglis. Yeah.
Chairman Baird. I will give my colleague more time to
finish.
Dr. Santer. Thank you, Chairman Baird. I really appreciate
the opportunity go on the record on this issue. I thank Pat
Michaels for referring to this as the most famous paper
published in climate science. And he criticized this analysis
back in 1996 when it was published.
I would like to address three aspects of that criticism
very briefly. The first aspect was that the editorial process
of Nature magazine had been interfered with, that somehow I had
imposed on Nature to publish this paper shortly before the
conference of the parties. That is wrong. That is incorrect.
The second claim is that there was selective data analysis
that we looked at a time period from 1963 to roughly 1988 in
observational weather balloon data, compared computer model
output with that. And then if you looked at a longer period of
record, you got different results.
First of all, Professor Michaels was right. If you looked
at a longer period of record, you did get different results.
Had there been intent to fool people to manipulate data? No. We
were doing a fingerprint analysis pattern--observational data,
grided data. And at that time they were only available from one
source. That source extended from 1973 through to 1988.
When Professor Michaels criticized our paper, we responded
as scientists do, we addressed the scientific criticism. What
we found was that when we looked at a newly available weather
balloon data set that went through to 1995, he was right, and
this change in the temperature asymmetry between the Northern
Hemisphere and Southern Hemisphere had this sort of u-shape.
What we were able to show and what others have convincingly
repeated since then is that that change is forced behavior. If
you look at models with combined changes in greenhouse gases
and sulfate aerosols, indeed the Stott paper that I mentioned
earlier shows that models--including greenhouse gases and
aerosol changes--replicate that behavior. It was not, as
Professor Michaels mentioned, some representation of natural
causes alone.
Actually doing the additional science strengthened our
confidence in the ability of the models to reproduce this
subtle interhemispheric temperature change difference. He has
not reported, unfortunately, on those responses to his
scientific criticism, which I do not think is correct.
Dr. Michaels. Can I--one thing.
Chairman Baird. I am going to recognize Mr. Inglis.
Dr. Michaels. Ask me questions after the hearing on this,
written questions.
Mr. Inglis. Okay. Good. I think it is very interesting to
kind of back-and-forth because it does show that scientists are
involved in trying to criticize each other's work and hope to
reach better science, which is very helpful. And then there are
some things that are sort of basic.
Ocean Acidification and Economic Impacts
And so, you know, I am not a scientist, but I play one on
the Science Committee when I am here. So we did this little
science experiment that I hope to convince some folks about the
ocean acidification. You know, what it is is an egg that we put
in vinegar, a vinegar water. And you come back in a couple of
days and--this is a science experiment you did in seventh
grade. There is no more shell. Now, this is of rather worldly
concern, because--rather than other-worldly and perhaps
academic debate in that--you know, my brother is a shrimper. If
he had his choice in what he would like to do. He has got to do
other things because you really can't make a living in South
Carolina shrimping. And so he has got a pickup truck in the
back. And the back of it says no wetlands, no seafood. Richard
is no tree-hugging environmentalist, but he is a guy who loves
to go shrimping. And he knows that if you don't have wetlands,
you don't have any seafood. And he is, I think, beginning to
see that if you melt the shells of these calcium-based
plankton, you end up with a hole in the bottom of the food
chain. It is a little bit of a problem to have a hole in the--
at the top of the food chain. You lose a polar bear, it is a
really bad day. But if you open a hole in the bottom of the
food chain--Dr. Feely, I think it is what you are talking
about--you have really ruined a lot of people's day. Because as
I understand it, there is something like a billion people
around the world that depend on the ocean for food, right? It
is something like that.
Dr. Feely. About 20 percent of the protein resources that
we as humans require come from the oceans.
Mr. Inglis. Yeah. And so--why don't you speak to the--am I
right about this, that this is sort of a seventh grade science
explanation of how it might work and the risk that we face and
the real-world consequences of Richard Inglis, a shrimper off
of Hilton Head?
Dr. Feely. Well, if we start at the marine phytoplankton
level which is the marine plants, about 11 percent of the
abundance of marine plants form calcium carbonate shells. These
are called coccolithophores. And they clearly show that the
formation of shell is decreased in a higher CO2
world. It is anywhere from nine to 45 percent. And then we go
up at the next level. The coccolithophores are generally eaten
by the zooplankton, and the zooplankton such as protozoans,
such as foraminifera, for example, or the pteropods that I
talked about, these free-swimming pteropods, you can see them
with your naked eye. That is the primary food source for
juvenile fish. That is what they want to eat because they don't
want to eat plankton per se. So they are dependent on those
pteropods and those species.
While living pteropods are placed in high CO2
water while still alive, well, the shell will begin to dissolve
within 48 hours. And the shell will be gone within a few weeks.
So this is a significant problem for that ecosystem.
Mr. Inglis. Is there doubt about the chemistry of higher
CO2 levels and impact on ocean acidification?
Dr. Feely. There is no doubt about that. And let me explain
why. We have worked at the international level with--through
the 1990 WOCE program, a Lowes hydrographic survey, with 8
countries working together, collecting over 72,000 samples in
the 1990s from surface to bottom along every portion of the
ocean, from Antarctica to the Arctic Ocean, from Japan to the
United States. All these countries worked together. The data
sets were brought to my laboratory. We processed the entire
data set and made all the corrections to the data set and that
allowed us to determine exactly where all the anthropogenic
CO2 was going. We did this by determining the
changes in anthropogenic CO2 since pre-industrial
times, using a combination of observations and models working
together.
We also had colleagues on those same cruises collecting
samples for the isotopic signature of that CO2, and
the changes in the isotopic signature were consistent with the
increase in anthropogenic carbon dioxide, which has a very
unique isotopic signature. And that penetration of the
anthropogenic CO2 goes down to, for the most part,
the upper 1,500 meters of the water column. So most of the
anthropogenic CO2 is still in the upper part of the
water count where most of our organisms live. And we know that
extremely well.
Now, in this decade, in 2000-2010, we have been repeating
those cruises. So we can see the direct changes to the uptake
of carbon dioxide from the atmosphere from the 1990s to the
present. And on those cruises, we see the same rate of change
of pH that we do at the time series sites at HOTS and BATS. So
we know now from the large extended surveys across our oceans
that we are seeing an exact rate of change of pH and CO2
increases in the water column. This is the only extreme one.
There is no debate about that at all.
Mr. Inglis. I think I am way over time, Mr. Chairman.
Chairman Baird. Thank you. I am not sure if it would be Dr.
Bartlett or Mr. Rohrabacher. Mr. Rohrabacher. Thank you, Dr.
Bartlett for your----
Science and the Federal Government
Mr. Rohrabacher. Thank you very much. And for the record, I
would like to place in the record a----
Chairman Baird. I cannot hear.
Mr. Rohrabacher. Can you hear me now? Let me--I would like
to place in the record a portion of President Eisenhower's
farewell remarks to the country in which he warned about what
happens when science and politics gets too intertwined and
government grants become the goal for various researchers.
Chairman Baird. Will that include the military-industrial
complex portion of it?
Mr. Rohrabacher. This was--that is exactly right.
Chairman Baird. I understand. I read the whole document. I
would never object to Mr. Eisenhower being entered into the
record.
[The information follows:]
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
Mr. Rohrabacher. What you need to understand is that
Eisenhower equated the threat of the military-industrial
complex with--similarly, with intertwining science and the
government.
Chairman Baird. Without objection.
More on Glaciers and Evidence of Anthropogenic Change
Mr. Rohrabacher. All right. Dr. Alley, with all due
respect, you didn't answer the Chairman's question. You know,
can--the question was a very good question. There have been
these back-and-forth between--on glaciers and the melting that
we have seen over and over again. Why did it happen, then, if
these same factors that you are blaming it on didn't exist
then?
Dr. Alley. I can give you as much or as little answer that
you would like.
Mr. Rohrabacher. Give me 15 seconds.
Dr. Alley. Okay. Give me 30 if I may.
Mr. Rohrabacher. Okay. Go ahead.
Dr. Alley. The ice ages are caused by features of Earth's
orbit. Your brightness is the sun. This, my head, is the earth.
This, through my nose, is the equator. Here, the top of my
head, is the North Pole. If the North Pole stood straight up,
you could never give me a sunburn on my bald spot. But in fact
as you know, it is tipped over a little bit and it nods a
little more and a little less over 41,000 years. Now, when it
nods more, my bald spot ice melts and the equator is a little
more shaded and now the ice grows and now the ice melts. But it
takes 41,000 years for this change to happen. We know what that
is doing right now and it is not fast enough to explain what we
are seeing.
Mr. Rohrabacher. No. You are trying to tell me all of the
other melts and backs-and-forth took all those thousands of
years? There wasn't a situation where on Mount Kilimanjaro you
had it--10 years you had this much ice and then the next year
you didn't and vice versa?
Dr. Alley. On Kilimanjaro, the records are fairly short. It
would be not the best one to lean on, unfortunately. You know,
what you do with glaciers--and I had hoped that I had made that
point--is that one glacier can do interesting things. The
world's glaciers tend to listen to the climate. And so you need
to take a large data set of glaciers to know what is going on.
What you then do find is that----
Mr. Rohrabacher. We all know that these things happen. The
major question that we will debate today--and I am again very
grateful to the Chairman for bringing this and having an honest
exchange of ideas--is what role mankind is playing. And thus if
mankind is playing a minor role, how does that then justify
some of what we consider to be Draconian solutions in
controlling human behavior that has been offered to us by
people who are espousing this particular theory?
Mr. Santer, I--let me ask you this. You said--I think it
was you who said--the sun--or some people try to say the sun
explains everything. No. A lot of people are trying to say the
sun explains a lot. Maybe you could explain to me why we have
noticed that there are similar trends of these meltings of the
polar ice cap that are going on on Mars. If it is not the sun
that is a major factor and human activity, why is that?
Dr. Alley. If I--if I may?
Mr. Rohrabacher. Sure. Go ahead.
Dr. Alley. Mars actually is linked a lot to the orbit as
well. It also has some dust storm issues to deal with.
Mr. Rohrabacher. Well, of course it does. But if we have
the same thing going on at the same time, and you are blaming
human activity for what is going on on Earth but you see it at
the same time on Mars, why do you automatically assume, well,
that must be human activity?
Dr. Alley. If, sir, I wanted to get a measure of how bright
the sun was and whether it was getting brighter or dimmer,
looking at an ice cap on Mars, which is changing its orbit, has
features which would change the sunshine, and it has dust
storms which change the sunshine. That is a very, very
indirect, imprecise measure when we have very precise
satellites that the people paid for with their taxpayer money,
which are measuring and then show no increase in the sun's
brightness.
Mr. Rohrabacher. You will have to correct me if I am wrong
because I am not a Ph.D.
Dr. Alley. Mars is a bad solar sensor and the satellites
are actually very good solar sensors.
Mr. Rohrabacher. But if you have a situation on Mars that--
you have that situation, is it just--when people talk about
solar activity, are we just talking about the brightness? Are
we talking about other type of solar activity that has an
impact on human--or not human climate, but the climate of this
planet and the other planets of the hemisphere?
Dr. Alley. It is a very interesting question that you ask,
sir, because at some level we know that we see the sun spot
cycle and we see a very weak response in the temperature. So we
know that the sun spots are affecting the climate. And it
actually looks like they are affecting it just a tiny bit more
than you would expect from the change in the brightness. So
there is a little possibility of a fine-tuning knob on the sun,
which is not just the brightness, it is other factors.
Mr. Rohrabacher. But we do know there has been these
changes because we do know that there was a medieval warming
period, even though we can see that there has been attempts
over the research--history of this research into global warming
of trying to basically negate the changes that took place
between the medieval period and the current period of time. But
was the temperature higher on the Earth during the medieval
period? Is there any evidence that the temperature got to be as
high? And if it did, how could we blame that, then, on the
production of CO2?
Dr. Alley. Yeah, we have fairly high confidence that--that
is why we call it the medieval climate anomaly. And it reflects
a low in volcanos blocking the sun and a slight high in the
brightness of the sun. And the best reconstructions that we
have indicate that it is not as warm as what we are having now.
But with uncertainties, that if you sort of go to the far
fringe, it just might be about where you are.
Now, this is a very interesting thing you bring up because
nature--you know, when the snow melts and the glaciers melt and
then they reflect less sun and they soak up more heat and get
us warmer, those positive feedbacks don't care whether we made
it warmer or whether the sun made it warmer, other things made
it warmer. They just care that it got warmer. So we actually
use the size of the medieval anomaly as one of many ways to
find out how much warming we might get from CO2.
Mr. Rohrabacher. That is the essence of the discussion
today. It comes down to whether or not this has--it is Mother
Nature or the master of the universe versus human beings doing
something that now--they now need to be controlled about. Dr.
Michaels, before my time is up, I should give you a chance to
comment.
Dr. Michaels. On that one? Well, I would look beyond the
medieval warm period and I would look at the end of the--what
is called the beginning of the postglacial period, for several
millennia where we know, based upon fallen trees--when a tree
falls in the tundra--or in the northern part of the
distribution--falls into acid, an acid environment and it is
saved, it is preserved so we can date the tree with carbon
dating and find out when it existed. We know that the boreal
forest, the north woods extended all the way to the Arctic
Ocean in Eurasia and, in fact, on to the Arctic Ocean islands.
We know that it has to be about 6 to 7 degrees Celsius. That
is, like, 12 degrees warmer in July for that forest to exist.
That is how much warmer it had to be.
Mr. Rohrabacher. And that is before human kind had any type
of impact on this. And let us note this.
But let us note this. Okay. Let us note this. But let us
note this. The actual statistics when you start your statistics
of how much warmer it is getting now, you are starting--you are
starting your calculations at the bottom of a 500-year decline
in world temperature which is the mini Ice Age. Is that right,
Dr. Michaels or Dr. Alley?
Dr. Alley. Yeah. No, it is very, very clear. A lot of my
work is reconstructing the history. Nature has changed climate
a lot by itself, for reasons that we understand reasonably
well, and we know are not active in this one.
Mr. Rohrabacher. That is the point.
Dr. Alley. If we were not here--you know, if humans weren't
here and we didn't care about anything that lives here--If this
were a video game, I would push the button and see what
happens, because it would be really exciting. But it is not a
video game.
Dr. Michaels. Well, the reason I brought up the Eurasian
arctic is because--again, it appears it was quite warmer for
millennia up there, and the only way you can get it--get it
that warm is to run water into the Arctic Ocean that is very
warm. And there is only one gate for the water. It is the
strait between Greenland and Europe. So that means the
temperature of at least eastern Greenland had to be quite a bit
warmer for a very long time, and the integrated warming is
probably greater than what we could produce if we tried to burn
as much carbon fuel as we could. And the ice still didn't
rapidly fall off of Greenland, as some people are saying it is
going to fall off in 100 years. Well, it didn't fall off a
couple of thousand years.
Dr. Alley. Central Greenland was about one degree warmer,
1-1/2 degree warmer based on about five lines of evidence that
I could summarize for you. Greenland was smaller during this
warm time by something like half a meter of sea level.
Dr. Michaels. But again, the scenario of the rapid loss of
ice simply didn't occur and that is--that is what is really
driving the policy on this. It is not the gradual warming that
is driving it.
Chairman Baird. For the record here, the stenographer here
can't record that Dr. Alley is periodically pointing to the top
of his head. And it is actually substantive, because his
argument was illustrated by the point that the angle of the
Earth relative to the sun can change over time with a bit of a
wobble and axis of the Earth. And the top of Dr. Alley's head
presumably represents the North Pole. I won't speculate where
the South Pole is. But the symbolism is apparently that the
Earth tips towards the sun and that may be accounting for some
of these prior periods in the absence of anthropogenic
CO2. I want to recognize----
Mr. Rohrabacher. Which is fine.
Dr. Michaels. And the polar bear survived and the Inuit
culture developed.
Chairman Baird. I want to recognize Dr. Bartlett.
Fossil Fuel Resources and Climate Change
Mr. Bartlett. Thank you very much. I apologize for my
absence. The Chevy Volt is on the Mall and I have been
scheduled for quite some time to speak briefly to the group
there at the introduction of the Chevy Volt to the Capitol
Hill. So I am very sorry that I missed your testimony.
You know, in the past, the Earth has been very much warmer.
We had subtropical seas at the north slope of Alaska or we
wouldn't have oil there, and there weren't any humans there
then. So clearly something else caused it. That does not mean
that our activities today aren't enormously important in
climate change because you are at--if you are at the tipping
point--if a car is half way over a cliff and it is at the
tipping point and then a little baby comes up and pushes on the
rear end of it, it is going over, isn't it? So if we are at the
tipping point, it is irrelevant whether our contribution is
small or great. If we are at the tipping point and we tip it
over, we have done it.
I had a chart that I had hoped that the staff could get up
on the screen. Can you get that up on the screen? Okay.
[The information follows:]
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And I want to apologize for my question to the first panel
because I know--I am a scientist. I know that scientists
shouldn't be concerned with policy. But the only reason you are
here is because we are concerned with policy and we would like
science to illuminate our policy. And so my question was better
directed to other people, you know, regardless of what the
science is, whether you agree with it or you disagree with it.
What the people want to do who want to move to less fossil
fuels is exactly the right thing to do for two other very good
reasons. If we can get that--this was the chart--and this is
quite a startling chart because just a few years ago nobody
would have predicted that--that we would be saying this today,
because our USGS was predicting that oil was going to be ever
more and more abundant, that the consumption of oil is going up
and up forever. That is in spite of the fact that in 1956 M.
King Hubbert predicted the United States would peak in 1970,
and we did right on schedule.
There is the chart up on the little screen over there. The
dark blue area--here it is on the screen behind you. The dark
blue area is conventional oil that we now know about that
peaked in 2006. And for the three or four years before the
recession, the production of oil worldwide was static and
demand was going up. With static supply and increasing demand,
the price went up 50, 100, $150 a barrel. Then we had the
recession which we should have capitalized on because it gave
us a little breather.
Of course we did none of that. And SUVs and pickup trucks
are back on the road in grand style in our country. But you
look at that chart there and what we are predicting--you see
that light blue area? You know, that is a dream. That is a
dream that says that we are going to find enough--more oil or
produce more oil from the sites that we have found. And many of
these new sites are deepwater sites, enormously difficult to
get at, enormously expensive to get at. I don't think that
there is even a prayer that we are even going to come close to
producing as much oil as they say we are going to produce by
developing the fields we now know and finding new fields.
If you look at the oil chart in the discovery zone, most of
them were in the past. The new oil--by the way, a large
discovery of oil is 10 billion barrels of oil. Every 12 days,
the world uses a billion barrels of oil. That is pretty simple
arithmetic. But 84 million barrels a day--84 goes into a 1,000
roughly 12 times, doesn't it? So if you have a 10 billion
barrel discovery of oil, oh, you breathe a sigh of relief. It
is all over, guys, we have got oil, 120 days that will last the
world. Big deal.
So, you know, what we are trying to do--I know the
scientists are concerned about science and I am a scientist,
but we are concerned about policy. And the only reason you are
here is because we want you to illuminate our policy. And
whether you agree with my colleague that we are a major factor
in this or not is totally irrelevant, because the right policy
is to do exactly what people want to do. If you believe that
human activity is increasing CO2 and changing the
climate, you want to move to fossil fuel. That is exactly the
same thing that those are concerned about national security
want to do. We have only two percent of the oil. We use 25
percent of the oil. We import 2/3 of what we use. Exactly the
same thing that people want to do who recognize--by the way,
the first person to recognize this was Hyman Rickover in 1957.
Pull up his speech. You can find the link on our website or do
a Google search for Rickover and energy speech. And one of the
really important things he said in that speech was that how
long the age of oil lasted was important in only one regard.
The longer it lasted, the more time we would have to plan an
orderly transition to other sources of energy.
I will close, Mr. Chairman, by noting that we in this
country have now blown 30 years. We knew of an absolute
certainty in 1980--when we look back to 1970, which is when M.
King Hubbert said that oil would peak in this country, we knew
with an absolute certainty that he was right about the United
States. Now, we tried to make him out a liar by doing a lot of
things. We have drilled more oil wells than all the rest of the
world put together. We have found oil, a lot of it, in Alaska
and the Gulf of Mexico. But in spite of those things, today we
produce half of the oil, less than half the oil than we did in
1970. He predicted the world would be peaking about now and we
are.
And so--if the policy we are looking for is whether or not
we have got to be moving away from fossil fuels to
alternatives, absolutely.
Just one more word. There are two kinds of energy that we
use--electricity and liquid fuels. The future will have all the
electricity that we need with more nuclear plants producing 80
percent with nuclear, with more wind and solar and micro hydro
and true geothermal. That is not your heat pump looking at 50,
60 degrees rather than 90 degrees in the summer and 10 degrees
in the wintertime. We will use as much electricity as we would
like to use.
The real crunch is going to be liquid fuels. If you are
wildly optimistic about every one of the possibilities for
liquid fuels, they don't--alternatives--they don't even come
close to 84 million barrels a day. Two bubbles have already
broken. One is the hydrogen bubble. Have you heard anybody talk
about hydrogen anymore? They finally figured out it is not an
energy source. It is just the equivalent of a battery that
carries energy from one place to another. Although real clean
when you use it. You get water when you burn it.
The second bubble that broke was the corn ethanol bubble.
The National Academy of Sciences has said that if we could turn
all of our corn into ethanol and discount it for a fossil fuel
input, still leaves you to pretend you are displacing fossil
fuels if you are simply using them in another form.
We would displace 2.4 percent of our gasoline--this is not
Roscoe Bartlett--this is the National Academy. They further
said--and this is their statement--that we would save more gas
than we would by turning all of our corn into ethanol if we
just tuned up our car and put air in the tires.
Now, the next bubble that is going to break is going to be
the cellulosic ethanol bubble. We will get something from
biomass. It will not even come close to what they hoped to get.
Life on this Earth is dependent largely, except what comes from
the sea, on about 8 or 10 inches of topsoil. That is topsoil
because it has organic material in it. This year's weeds grow
largely because last year's weeds died and are fertilizing
them. We can only for a short period of time rape the topsoil
and get away with it.
What is the sustainability of cellulosic ethanol? That is
the next bubble that will break. We just have to come to the
realization that fossil fuels or liquid energy in the amounts
that we would like to use it just aren't going to be there. We
are going to go largely to an electric world, an electric car.
You can't electrify the airplane, by the way. And big trucks
won't run on batteries very well. So we are going to have a
very--and this is a very challenging future for me, Mr.
Chairman, because every six hours we go another billion dollars
in debt and every 12 hours we have another billion dollar trade
deficit.
The jobs that went overseas aren't coming back, so we have
got to create new ones. And my dream is that we can create
those new jobs in the green area and we can once begin--become
a major exporting country. And this Committee is going to be
very important in that regard in sponsoring the basic science
that will make this green technology.
I am sorry I ran over my time, but this is something
obviously that I am kind of passionate about. Thank you very
much for holding the hearing.
Chairman Baird. One would not detect the passion. Dr.
Bartlett, I appreciate the eloquence and the sentiments and
echo them myself. I share them. And as I mentioned at the
outset, you have embodied them in your own choices about how
you power your own life. And it is admirable that you do.
The Impacts of Current CO2 Emissions
One last question for Dr. Feely, if I may. One of the
concerns that many of us have about--about this phenomenon is
to what extent are we making decisions now that put us well
down the road of a long-term impact even if we make changes
today? And so the--sort of at what point do we start bending
the curve in the right direction?
My understanding is that--is that--well, enlighten us. To
what extent is the CO2 already present going to
cause problems for the ocean?
Dr. Feely. That is the exact question that the scientific
community is wrestling with right now. And there is already
evidence from looking at organisms in sea water; we already see
that we have already had an impact. Foraminifera shells are
getting smaller. You can compare shells that are collected at
present with living organisms to which shells that were on the
bottom of the sea from 200 years or longer ago; there is a
significant difference. So we already know that we are having
impacts.
We know with our own shellfish industry on the west coast
that we are having significant impacts. Have we reached a
tipping point yet? This is the question we are really asking
ourselves. And it is very hard to answer that question. What we
do know for sure, if we get above 450 parts per million, we
will cause the Arctic Ocean and the Antarctic Ocean to go
corrosive from top to bottom. That is a tremendous impact on
that----
Chairman Baird. Say that again. To go corrosive----
Dr. Feely. Corrosive from top to bottom throughout the
entire water column.
Chairman Baird. Corrosive to the marine organisms at----
Dr. Feely. To the calcifying organisms, which means that
the pH would be about 7.7 or so. And consequently, that is not
too far away. And we have to begin to concern ourselves of
whether or not we will go much farther in terms of CO2
levels beyond that which would impact large areas of the
Pacific and Atlantic Oceans as well.
The projections out to the end of the century say that we
would have CO2 levels as high as 800 parts per
million, which would have impacts on the entire southern ocean,
would impact the coral reefs throughout the world oceans, and
would even impact our deepwater corals which we know very
little about.
Chairman Baird. So let me just make sure I understand. We
are already having problems with current rates of CO2
in the atmosphere. At projected increases with economic
development, et cetera, if we don't change, as Dr. Bartlett has
been talking about, if we don't change our energy system to a
less fossil fuels-based energy system, the projected levels
could reach levels where in the major polar regions and
elsewhere in the oceans, the water itself would become
corrosive to the organisms that have evolved over many millions
of years to live there, and the base food chain for much of
ocean life could be significantly impacted. Is that a fair
statement?
Dr. Feely. That is absolutely correct.
Chairman Baird. Now, this highlights something that is
fundamental to this hearing and it is this. It goes back to my
friend Dr. Bartlett's analogy. If your car might be at the
tipping point and even if there is some uncertainty about that,
do you tell the baby to stop pushing? It just seems to me if
the car is going to go off the bloody cliff, if there is doubt,
you stop pushing, especially when the solution can be
beneficial to your economy, beneficial to your national
security perspective, beneficial to your environment,
beneficial to human health. Why not stop pushing, for goodness'
sake, if there is doubt?
And Bob Inglis had the example earlier, the analogy. We
have bent over backwards on this Committee and this hearing
today to include folks like Dr. Michaels, Dr. Lindzen. But the
reality is surveys of topflight scientists have shown the vast
majority suggest that there is real reason for concern. And if
there is real reason for concern, should we not tell the baby
to stop pushing if we have ways to do it?
So I thank this panel. We are now going to talk further
about what possible impacts might be. I thank the panel. It has
been a spirited discussion, a constructive one. Again, as I
have done before for folks--please, Dr. Bartlett.
Mr. Bartlett. I cannot stay. But I would like to note that
the importance of these hearings is not the fact that some
Congressman is up here listening to you. The importance of this
hearing is that it is on the record. And so thank you very much
for coming.
The next panel will be on the record. I really regret that
I can't be here. But my Chairman will ask the questions that I
might have asked and do it better than I.
Chairman Baird. Well, Doctor, I can't do it better than
you, I am sure, my friend. But one thing I am certain of--and I
was going to say--you anticipated it. The transcript, the
written transcripts, the oral transcripts, the video of this
will be on the record. So people can actually access the
Committee website if you can't sit through the whole thing or
don't want to.
And having had the privilege to read all the transcripts. I
note for example, Dr. Cullen, if you want to get a really
marvelous, understandable grasp of the history of this, I think
Dr. Cullen's testimony is just spectacular in that regard. And
all of the others are. Some of it is, frankly, too deep for me
and others, but you will get the sense. And I think it is good.
And, Dr. Bartlett, thanks.
With this, I thank our panelists for their presentations
today and their years of scientific work. We will take a five-
minute recess followed by the final panel. Let's reconvene in
about 30 seconds if we can. I know we are having spirited
discussion. But let's try to reconvene so that we can hear from
our extraordinarily distinguished final panel whose patience I
greatly appreciate and--as do I appreciate that of our guests
in the audience today and my colleagues who have, for very
understanding reasons, had to depart. But I am very, very
grateful, again.
This is available to Members of Congress, their staff, and
to the general public and media on our website. And so I hope
you will not consider the fact that we have very important and
unfortunately timed organizational meetings on both the
Democratic and Republican side happening as we speak. Again, we
did our level best to be sure people were here and in the
process made sure people were somewhere else, which was a
misfortune. But the fact that you are all here is what matters
the most in my judgment. And the fact that our colleagues who
care--and I hope they do care--will have a chance to review all
of the testimony is tremendously important. And thus we begin
our final panel as soon as I can find the introductory page.
[Recess.]
Panel III
Chairman Baird. Thus we begin our final panel, as soon as I
can find the introductory page.
Here we go. Again, appreciate the witness's presence.
Rear Admiral David W. Titley is the Oceanographer and
Navigator of the United States Navy. I love that title. The
Navigator for the United States Navy. Every time a ship crashes
into another ship it's your fault, right?
Admiral Titley. Yes, sir.
Chairman Baird. Mr. James Lopez, Senior Advisor to the
Deputy Secretary for the U.S. Department of Housing and Urban
Development. Mr. Lopez, thanks for being here.
Mr. William Geer is the Director of the Center for Western
Lands of the Theodore Roosevelt Conservation Partisanship; and
Dr. Judith Curry, the Chair of the School of Earth and
Atmospheric Sciences at Georgia Institute of Technology. Thank
you, Doctor, for being here.
We will begin our testimony. As you saw, we will try to
limit the initial comments to around five minutes, and then we
will follow up with questions. Thank you.
We will begin with Admiral Titley. Thank you.
STATEMENT OF REAR ADMIRAL DAVID W. TITLEY, OCEANOGRAPHER AND
NAVIGATOR OF THE U.S. NAVY
Admiral Titley. Thank you, sir.
Mr. Chairman, and distinguished colleagues, I want to thank
you for the opportunity to address you today regarding why the
Navy cares about climate change and how we are responding to
the opportunities and challenges it presents. Rather than read
from my written statement, sir, I will provide brief
introductory remarks on the topic and invite any questions from
you.
The 2010 Quadrennial Defense Review, or----
Chairman Baird. You have a voice that I could hear, but
without the mic apparently the others didn't.
Admiral Titley. Are we on? Okay. Have to be five percent
smarter than the microphone.
The 2010 Quadrennial Defense Review, or QDR, and 2010
National Security Strategy both require the Department of
Defense to take action regarding climate change by recognizing
the effects climate change may have on its operating
environment, roles, missions, facilities, and military
capabilities. Taking into account this guidance, the Navy
recognizes the need to adapt to climate change and is closely
examining the impacts that climate change will have on military
missions and infrastructure.
The Navy is watching the changing Arctic environment with
particular interest. The changing Arctic has national security
implications for the Navy. The Navy's maritime strategy
identifies that new shipping routes have the potential to
reshape the global transportation system.
The QDR identifies the Arctic as a region where the
influence of climate change is most evident in shaping the
operating environment and directs the Department of Defense to
work with the Coast Guard and the Department of Homeland
Security to address gaps in Arctic communications, domain
awareness, search and rescue, and environmental observation and
forecasting capabilities.
There are other impacts of climate change on missions that
the Navy must consider, including water resources and fisheries
redistribution, shifting precipitation patterns, and
implications for humanitarian assistance and disaster relief.
The Navy must understand where, when, and how climate change
will affect regions around the world and work with Federal
partners to develop the capabilities needed to ensure readiness
in the 21st century.
The Navy must also be aware of impacts to military
infrastructure both within and outside the continental United
States due to increased sea level rise and storm surge. The
Navy's operational readiness hinges on continued access to
land, air, and sea training and test spaces; and many overseas
bases provide strategic advantage to the Navy in terms of
location and logistic support. Any adaptation efforts
undertaken are required to be informed by the best possible
science and initiated at the right time and cost.
The Navy is currently beginning assessments that will
inform Navy strategy, policy, and plans. The Department of
Defense is already conducting adaptation efforts through a
variety of activities, including two Navy roadmaps on the
Arctic and global climate change and the leveraging of
cooperative partnerships to ensure best access to science and
information. For example, the Navy is partnering with the
National Oceanic and Atmospheric Administration [NOAA] and the
United States Air Force to advance U.S. environmental
prediction capability to mitigate the impact of severe weather
and answer operational requirements facing our Nation.
The Navy understands the challenges and opportunities that
climate change will present to its missions and installations.
We are beginning to conduct the assessments necessary to inform
future investments and are initiating adaptation activities in
areas where we have enough certainty with which to proceed.
Thank you, sir, and I stand ready to answer any questions
the Subcommittee may have.
[The prepared statement of Admiral Titley follows:]
Prepared Statement of David Titley
Mr. Chairman, members of the subcommittee and distinguished
colleagues, I want to thank you for the opportunity to address you
today regarding the Navy's climate change interests. My name is Rear
Admiral David Titley and I am the Oceanographer of the Navy and the
Director of Navy's Task Force Climate Change. The Chief of Naval
Operations, Admiral Gary Roughead, established Task Force Climate
Change in May of 2009 to address implications of climate change for
national security and naval operations. Today I am speaking about why
the Navy cares about climate change and how we are responding to the
challenges and opportunities it presents.
The 2010 Quadrennial Defense Review (QDR) identifies climate change
as an issue that will play a significant role in shaping the future
security environment, and directs the Department of Defense to take
specific action to reduce the risks associated with climate change,
while also identifying climate change and energy security as
``inextricably linked.'' In addition, climate change is addressed in
the 2010 National Security Strategy, which states that the issue is a
key challenge requiring broad global cooperation.
The QDR discusses how climate change will affect the Department of
Defense (DoD) in two broad ways: first, by shaping the operating
environment, roles, and missions that we undertake due to physical
changes such as rising temperature and sea level, retreating glaciers,
earlier snowmelt, and changing precipitation patterns and geopolitical
impacts resulting from these changes; and second, the QDR describes the
need for DoD to adjust to the impacts of climate change on our
facilities and military capabilities by constructing a strategic
approach that considers the influence of climate change.
In addition, DoD participates in the Interagency Climate Change
Adaptation Task Force. In October, the Task Force submitted a progress
report to the President with recommendations for how Federal policies
and programs can better prepare the Nation to respond to the impacts of
climate change. The Task Force recommended that Agencies and
Departments, including DoD, make adaptation a standard part of planning
to minimize climate risks and damages and to ensure that resources are
invested wisely and that services and operations remain effective in a
changing climate.
Taking into account the DoD guidance and Interagency Climate Change
Adaptation Task Force recommendations, the Navy recognizes the need to
adapt to climate change and is closely examining the impacts that
climate change will have on its military missions and infrastructure.
In terms of climate change impact on missions, the Navy is watching
with great interest the changing Arctic environment. September 2007 saw
a record low in sea ice extent and the declining trend has continued--
September 2010 was third lowest extent on record and the overall trend
has shown an 11.2 percent decline per decade in seasonal ice coverage
since satellites were first used to measure the Arctic ice in 1979.
Perhaps more significantly, estimates from the University of
Washington's Applied Physics Lab show that the amount of sea ice
continues to decrease dramatically. September ice volume was the lowest
recorded in 2010 at 78 percent below its 1979 maximum and 70 percent
below the mean for the 1979-2009 period. Regardless of changes to sea
ice, the Arctic will remain ice covered in the winter through this
century and remains a very difficult operating environment. The
changing Arctic has national security implications for the Navy. The
QDR identifies the Arctic as the region where the influence of climate
change is most evident in shaping the operating environment and directs
DoD to work with the Coast Guard and Department of Homeland Security to
address gaps in Arctic communications, domain awareness, search and
rescue, and environmental observation and forecasting capabilities. The
Navy's Maritime Strategy identifies that new shipping routes have the
potential to reshape the global transportation system. For example, the
Bering Strait has the potential to increase in strategic significance
over the next few decades as the ice melts and the shipping season
lengthens, and companies begin to ship goods over the pole rather than
through the Panama Canal.
While the Arctic is a bellwether for global climate change, there
are other impacts of climate change on missions that the Navy must
consider, including water resources, fisheries, and implication for
humanitarian assistance and disaster relief. Availability of freshwater
will change with the redistribution of precipitation patterns and
saltwater intrusion resulting from sea level rise. Furthermore,
alterations in freshwater systems will present challenges for flood
management, drought preparedness, agriculture, and water supply. On the
other hand, some areas of the world, such as Russia, will likely see
longer growing seasons and an increase in water availability,
potentially providing opportunities for economic growth. In addition to
water supply, large scale redistribution of fisheries catch potential
is a concern in areas of the world that depend heavily upon this
industry as a primary food source. Leading fishery scientists estimate
decreases of up to 40% in overall catch potential for most major
fisheries near the tropics over the next four decades due to warming
and changes in ocean chemistry, while the Arctic region may see an
increase in overall catch potential. Further impacts to marine
ecosystems will be caused by ocean acidification, often referred to as
``global warming's silent partner.'' Shifting precipitation patterns
and frequency of floods and droughts may generate humanitarian
assistance and disaster response requirements and the Navy, with its
expeditionary capabilities, may be tasked to support these requests in
accordance with the 2010 National Security Strategy, which states that
``a changing climate portends a future in which the United States must
be better prepared and resourced to exercise robust leadership to help
meet critical humanitarian needs.'' The Navy must understand where,
when, and how climate change will affect regions around the world and
work with federal partners to develop the capabilities needed to ensure
readiness in the 21st century.
In addition to impacts to Navy missions, we must be aware of
impacts to military infrastructure, both within and outside of the
Continental United States. The recent National Research Council Report,
``Advancing the Science of Climate,'' notes that many United States
military bases are located in areas likely to be affected by sea level
rise and tropical storms. The Navy's operational readiness hinges on
continued access to land, air, and sea training and test spaces.
Coastal infrastructure is particularly vulnerable because it will be
affected by changes in global and regional sea level coupled with a
potential increase in storm surge and/or severe storm events. Overseas
bases may be impacted by sea level rise, changing storm patterns, and
water resource challenges. Bases such as Guam and Diego Garcia provide
a strategic advantage to the Navy in terms of location and logistics
support.
The potential impacts of climate change on Navy missions and
infrastructure require adaptation efforts that are informed by the best
possible science, and initiated at the right time and cost. For
example, the Strategic Environmental Research and Development Program
(the DoD's environmental science and technology program) is currently
funding four research projects, situated in different geophysical
settings along the US coastline, that collectively are developing the
physical process models and assessment methodologies needed to assess
the impacts of sea level rise and associated storm surge on DoD coastal
installations. In addition, via its recently submitted Strategic
Sustainability Performance Plan mandated by Executive Order 13514, DoD
has articulated is strategy for a QDR-directed, comprehensive
assessment of military installations to assess the potential impacts of
climate change on DoD's missions. The associated research and
development aspects of this effort will result in impact and
vulnerability assessment tools designed for military installations,
regionally applicable climate change information, and adaptation
strategies appropriate for DoD requirements. The Defense Science
Board's Task Force on Trends and Implications of Climate Change for
National and International Security is making recommendations on the
role DoD should play in dealing with other U.S. government agencies to
mitigate potential consequences of environmental change in areas
important to U.S. national security. The Navy has sponsored the
National Research Council's Naval Studies Board to study the national
security implications of climate change on U.S. Naval forces, and is
currently conducting a Capabilities Based Assessment for the Arctic to
identify capabilities required for future operations in the region and
possible capability gaps, shortfalls, and redundancies. Assessments
such as these will inform Navy strategy, policy, and plans to guide
future investments.
The Navy is already executing adaptation efforts through a variety
of activities. The Navy is conducting wargames that include climate
change impacts on future tactical, operational, and strategic Naval
capabilities. Within the last year the Navy promulgated two roadmaps
concentrated on the Arctic and global climate change. The roadmaps
guide strategy, future investment, action, and public discussion on the
Arctic and global climate change. The Navy Arctic Strategic Objectives,
released in May 2010, specify the objectives required to ensure the
Arctic remains a safe, stable, and secure region where U.S. national
and maritime interests are safeguarded and the homeland is protected.
This past summer, the Navy participated in Canada's largest annual
Arctic exercise, Operation NANOOK, which provided our sailors valuable
operating experiencing in the region. The Navy established Task Force
Energy to meet the growing energy challenges that we face as a service
and a nation, and subsequently, the five energy goals as outlined by
the Secretary of the Navy. Task Force Climate Change and Task Force
Energy work closely to ensure that overlapping issues of climate change
and energy security are addressed.
Furthermore, the Navy is actively leveraging interagency,
international, and academic partnerships to ensure it has access to the
best science and information and to avoid duplication of efforts. We
are participating, in coordination with appropriate DoD offices, in
many of the interagency efforts being conducted on climate change,
including the National Science and Technology Council's Roundtable on
Climate Information and Services, co-chaired by the Office of Science
and Technology Policy, the National Oceanic and Atmospheric
Administration, and the U.S. Geological Survey and the U.S. Global
Change Research Program's National Climate Assessment, which in part
are coordinating agency climate science needs and adaptation efforts
across the federal government. Finally, the Navy is joining an effort
with the Air Force and the National Oceanic and Atmospheric
Administration to advance U.S. environmental prediction capability to
mitigate the impact of the severe weather and answer operational
requirements facing our nation. This capability will combine the
forecasting skills of the Navy's and the National Weather Service's
global numerical weather, ocean, and ice models to provide a better
Earth Systems Prediction Capability.
I would like to close with a quote from Vice Admiral Richard Truly,
former NASA Administrator, and Director of Department of Energy's
National Renewable Energy Lab. ``The stresses that climate change will
put on our national security will be different than any we've dealt
with in the past . . . this is why we need to study this issue now, so
that we'll be prepared and not overwhelmed by the required scope of our
response when the time comes.'' The Navy understands the challenges and
opportunities that climate change presents to its missions and
installations. We are beginning to conduct the assessments necessary to
inform future investments and are initiating adaptation activities in
areas where we have enough certainty with which to proceed.
Thank you Mr. Chairman and I look forward to answering any
questions the Subcommittee may have.
Biography for David Titley
[GRAPHIC(S) NOT AVAILABLE IN TIFF FORMAT]
A native of Schenectady, N.Y., Rear Admiral Titley was commissioned
through the Naval Reserve Officers Training Commissioning program in
1980. While aboard USS Farragut (DDG 37) from 1980-1983, Titley served
as navigator, qualified as a surface warfare officer, and transferred
to the Oceanography community the following year.
Subsequent sea duty included tours as oceanographer aboard USS
Belleau Wood (LHA 3) 1985-1987, USS Carl Vinson (CVN 70) in 1990,
Carrier Group 6 1993-1995 and U.S. 7th Fleet 1998-2000. Titley has
completed seven deployments to the Mediterranean, Indian Ocean and
Western Pacific theaters. His Belleau Wood deployment included winter-
time amphibious operations north of the Aleutian Islands.
Titley has commanded the Fleet Numerical Meteorological and
Oceanographic Center in Monterey Calif., and was the first commanding
officer of the Naval Oceanography Operations Command. He served his
initial flag tour as commander, Naval Meteorology and Oceanography
Command.
Previous shore tours include assignments at the Regional
Oceanography Centers at Pearl Harbor and Guam, the Naval Oceanographic
Office, on the staff of the Assistant Secretary of the Navy (Research,
Development and Acquisition), Office of Mine and Undersea Warfare, as
the executive assistant to the Principal Deputy Assistant Secretary of
the Navy (Research, Development and Acquisition) and as chief of staff,
Naval Meteorology and Oceanography Command.
Titley also served on the U.S. Commission on Ocean Policy, as
Special Assistant to the Chairman (Admiral (ret.) James Watkins) for
Physical Oceanography and as senior military assistant to the Director
of Net Assessment in the Office of the Secretary of Defense.
In 2009, Titley assumed duties as oceanographer and navigator of
the Navy.
Education includes a Bachelor of Science in meteorology from the
Pennsylvania State University, a Master of Science in meteorology and
physical oceanography and a Ph.D in meteorology, both from the Naval
Postgraduate School. His dissertation concentrated on better
understanding Tropical Cyclone Intensification. In 2003-2004, Titley
attended the Massachusetts Institute of Technology Seminar XXI on
Foreign Politics, International Relations and National Interest. He was
elected a Fellow of the American Meteorological Society in 2009.
Chairman Baird. Thank you very much, Admiral.
Mr. Lopez.
STATEMENT OF JAMES LOPEZ, SENIOR ADVISOR TO THE DEPUTY
SECRETARY, U.S. DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT
Mr. Lopez. Thank you very much.
Is that on? No? How about now? Good?
Good morning, Chairman Baird, Ranking Member Inglis,
Members of the Subcommittee. My name is Jim Lopez, and I am the
Senior Advisor to Deputy Secretary Ron Sims at HUD. Thank you
for the opportunity to testify today.
On behalf of Secretary Shaun Donovan and Deputy Secretary
Sims, I appreciate this opportunity to tell you how HUD--
individually and in partisanship with other federal agencies--
is working to develop more sustainable, resilient communities
across the Nation. In fact, we believe that sustainable
communities are resilient communities.
Before coming to HUD, I worked on climate change issues in
King County, Washington State; and over the past year, I have
had the opportunity to serve as part of the President's
Interagency Climate Change Adaptation Task Force, which is
chaired by the Council on Environmental Quality, NOAA, and the
Office of Science and Technology Policy and includes 20 federal
agencies and executive branch offices.
The Council last month released its progress report, with
charts and a roadmap for federal action on climate adaptation
and resilience. The report highlights the need to better
understand and prepare for climate change and offers a flexible
framework for federal agencies to engage in that important
work.
The fact is that even if we could halt greenhouse gas
emissions today, the scientific evidence, as we have heard
today, suggests that the world would still experience changing
climate for decades to come. While government efforts have
tended to focus on reducing greenhouse gas emissions, climate
mitigation, there should be an increasing focus on preparing
for and responding to the threat that climate change impacts
already represent to our social well-being, the economy, and
the environment. That is climate resilience, and that is where
I would like focus my remarks today.
I would like to make three quick points.
First, as noted before above, we must continue to work to
reducing GHG emissions. We must also step up our efforts to
prepare for and respond to climate change. Across the country,
cities, counties, and states are putting in place strategies to
adapt to risks and stresses caused by climate change such as
flooding and extreme precipitation, temperature spikes, and
urban heat island effects, water shortages and drought, and
rises in sea level in coastal communities.
Second, there is a growing recognition that if we are to
make progress on climate change, we need to focus on the built
environment. That is on where we build, how we build, and how
we move people and goods to the places we live, work, and play.
And, third, it's important that we tackle climate change in
ways that respect and protect the most vulnerable populations:
infants and children, pregnant women, the elderly with chronic
medical conditions, low-income households, and outdoor workers.
And I am pleased to report to you that the Federal
Government is paying attention to climate resilience. Federal
agencies are supporting local efforts to adapt the built
environment to these new challenges and to protect vulnerable
populations through innovative programs and partnerships.
In HUD, we have formed an unprecedented partisanship with
EPA and DOT, the Partisanship for Sustainable Communities,
which will, we hope, result in reduced carbon emissions as we
draw attention to the benefits of more compact, walkable, and
climate-friendly communities.
We also hope to show that sustainable communities are
resilient communities as HUD requests for proposals explicitly
encourage communities to address climate adaptation and
resilience as part of their regional planning efforts.
Another important component of HUD and the Federal
Government's work to support sustainable communities is in the
area of energy efficiency and green building. Properly
implemented and maintained, investments in energy retrofits can
significantly reduce energy use in existing buildings,
improving comfort for residents and lowering carbon emissions.
Let me conclude by briefly touching on what we are doing to
foster similar cooperation between federal agencies on climate
adaptation. The Interagency Climate Change Adaptation Task
Force, of which HUD is a member, submitted a report to the
President emphasizing the importance of this issue to the
Federal Government. President Obama signed an executive order
in October, 2009, that called on the task force to recommend
how federal agencies could play a role in a national climate
change adaptation strategy. In the progress report we released
last month, we reaffirmed the Obama Administration's commitment
to mitigating greenhouse gas emissions and in the long term to
improve our ability to manage the impact these emissions have
on our lives. Mitigation and adaptation are inextricably linked
and both are required in order to reduce the impacts of climate
change.
The task force recommended in its progress report that
federal agencies make adaptation a standard part of strategic
planning to ensure that resources are invested wisely and that
federal programs, services, and operations remain effective in
a changing climate. In short, the federal response is rising to
the level of the challenges before us.
Thank you, Mr. Chairman. I looked look forward to answering
your questions.
[The prepared statement of Mr. Lopez follows:]
Prepared Statement of James C. Lopez
Good morning, Chairman Baird, Ranking Member Inglis, members of the
Subcommittee. My name is Jim Lopez, and I am Senior Advisor to Deputy
Secretary Ron Sims at HUD, who has been tasked by Secretary Donovan to
lead HUD's climate change efforts. Thank you for this opportunity to
testify today.
On behalf of the Deputy Secretary and Secretary Donovan, I want to
thank and commend you for your leadership in developing and pushing for
innovative and integrated approaches to the critical issue of climate
change. I appreciate this opportunity to tell you how we at HUD--
individually and in partnership with other federal agencies--are
working to develop more sustainable, resilient communities across the
nation.
I should note that this is an issue with which I've had hands-on
experience at the local level. Before coming to HUD, I coordinated King
County's climate change preparedness initiative in Washington State and
I was a contributing author to Preparing for Climate Change. A
Guidebook for Local, Regional and State Governments.\1\ My experience
at the county level has given me an important perspective on what the
federal government could and should be doing on this critical issue.
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\1\ ICLEI, University of Washington, 2007.
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Efforts to curb greenhouse gas emissions, known as climate change
mitigation, have become a widespread imperative for all levels of
government. However, scientific evidence indicates that even if we
could halt greenhouse gas (GHG) emissions today, the world would still
experience a changing climate for decades to come due to the long-lived
nature of carbon dioxide and other greenhouse gases as well as the
absorption of heat by oceans.\2\ While federal, state, and local
efforts, including HUD's, have tended to focus on reducing GHG
emissions, there is an increasing focus on developing complementary
climate resilience strategies, defined by the National Research Council
of the National Academy of Sciences as the ``capability to prepare for,
respond to, and recover from significant multi-hazard threats with
minimum damage to social well-being, the economy and the
environment.\3\ ''
---------------------------------------------------------------------------
\2\ Council on Environmental Quality, Progress Report of the
Interagency Climate Change Adaptation Task Force, p. 15.
\3\ National Academy of Sciences, National Research Council,
Adapting to the Impacts of Climate Change, Prepublication Copy.
Climate Change and the Built Environment
The consequences of climate change are complex and far reaching. It
is becoming increasingly clear that GHG emissions, the primary cause of
climate change, are in large part a result of energy use in our built
environment--either as a result of energy use in buildings themselves,
or transportation energy used to move people and goods.\4\
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\4\ Energy Information Administration, http://www.eia.doe.gov/oiaf/
1605/ggccebro/chapter1.
html. Buildings generate about 40 percent of emissions overall, and
transportation generates 28 percent.
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Climate change is affecting many aspects of our society, our
livelihoods and our environment. Communities across the nation are
experiencing climate change impacts, such as changes in average
temperatures, more extreme weather events, and rising sea levels.\5\
---------------------------------------------------------------------------
\5\ Karl, Thomas R, Melillo, Jerry M. Peterson, Thomas C Global
Climate Change Impacts in the United States (2009), cited in Progress
Report, of the Interagency Climate Change Adaptation Task Force, p. 15
(2010).
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The effects of climate change are expected to be significant for
both rural communities and metropolitan regions (where most of the
built environment is located). As a federal cabinet agency focused on
the built environment, on strengthening metropolitan areas as well as
rural communities, and expanding opportunity for all Americans, we at
HUD recognize the need to take action.
Reducing GHG emissions in the built environment is essential to
making progress on climate change at the speed and scale required.
Across the country, cities, counties and States are finding innovative
solutions to climate change that involve the built environment--from
King County to Miami-Dade County, from Chicago to Los Angeles, from
Milwaukee to New York City, and from Phoenix to San Francisco. In
addition, home builders and community- and faith-based organizations,
public housing authorities and private building owners, and financial
institutions and foundations are taking action to prepare the built
environment for climate change.\6\
---------------------------------------------------------------------------
\6\ Center for Clean Air Policy, Ask the Climate Question: Adapting
to Climate Change Impact in Urban Regions (June 2009).
---------------------------------------------------------------------------
These communities--and many others--are putting in place strategies
to adapt to risks and stresses caused by climate change, such as
flooding and extreme precipitation; temperature spikes and urban heat
island effects; water shortages and drought; and rises in sea-level in
coastal communities.\7\
---------------------------------------------------------------------------
\7\ Ibid, p. 11-14.
Addressing Vulnerable Populations
Critical to all of these efforts is the need to pay particular
attention to the impact of climate change on vulnerable populations. As
noted in the National Research Council's Report, Adapting to the
Impacts of Climate Change, groups with increased vulnerability to
climate change are infants and children, pregnant women, the elderly
with chronic medical conditions, low-income households, and outdoor
workers.\8\
---------------------------------------------------------------------------
\8\ Adapting to the Impacts of Climate Change, National Academies
of Sciences, 2010, pp.32-33.
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Low-income, often minority, families are frequently most at risk
from the effects of extreme heat that will become more frequent due to
climate change. They may be unable to afford the high cost of utilities
in these conditions, or invest in the cooling equipment needed to
mitigate these effect--often with tragic results.\9\
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\9\ Center for Clean Air Policy, Ask the Climate Question: Adapting
to Climate Change Impact in Urban Regions, p.12, June 2009. In Chicago,
for example, upward of 600 mostly poor, elderly and African American
persons died in the wake of a sever heat wave in that city. As a
result, Chicago has adopted an aggressive plan to enhance its
capability to manage heat waves.
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As noted by the U.S. Global Science Research Program, ``in the
future (as in the past), the direct impacts of climate change are
likely to fall disproportionately on the disadvantaged. People with few
resources often live in conditions that increase their vulnerability to
the effects of climate change. The fate of the poor can be permanent
dislocation, leading to the loss of social relationships and community
support networks provided by schools, churches and neighborhoods.''
\10\
---------------------------------------------------------------------------
\10\ Karl, Melillo and Peterson, Global Climate Change Impacts in
the United States (2009).
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That's why we asked grant applicants for HUD's new regional
sustainability planning grants (described below) to pay particular
attention to addressing the needs of low-income and underserved
populations; and why we are expanding our efforts to lower carbon
emissions through improved energy efficiency in the affordable housing
sector. Let me describe these initiatives in more detail.
HUD's Role--Sustainable Communities Initiative
I am pleased to report that through the Sustainable Communities
Initiative HUD is supporting a new generation of community and regional
planning that we think will result in more climate resilient
communities. Just last month Secretary Donovan announced the first
Regional Planning Grants to be awarded under the Sustainable
Communities Initiative--our flagship effort to enable communities to
develop more integrated regional responses to both mitigating, and
adapting to the effects, of climate change.
This initiative is being implemented through an unprecedented
partnership with EPA and DOT, the Partnership for Sustainable
Communities. This important cross-agency collaboration is designed to
encourage integrated solutions to the multidimensional environmental,
housing and transportation challenges faced by cities and suburbs and
rural areas.
The initiative will foster collaboration across jurisdictional
lines and enable metropolitan leaders to ``join up'' housing,
transportation, and other policies to address the critical issues of
affordability, competitiveness, and sustainability. Moreover, our
partnership with EPA encourages recipients to consider water
infrastructure planning and conservation along with their housing and
transportation plans. As noted in the National Academy of Sciences
Report, climate change will place additional burdens on already
stressed water resources. More intense droughts and flooding events are
projected to become common in some regions.\11\
---------------------------------------------------------------------------
\11\ National Academy of Sciences, Adapting to the Impacts of
Climate Change, p.34 (2010).
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HUD's Notice of Funds Availability (NOFA) for the regional
sustainability planning grants encouraged communities to address
climate adaptation and resilience as part of their regional planning
efforts. Eligible activities include:
Conduct comprehensive climate change impacts assessments to
guide regional planning and implementation strategies.
Assessments may comprehensively evaluate a range of likely
climate change impacts or may focus on an impact area of
special concern in the region (e.g.: sea level rise or reduced
water availability. Findings from climate impact assessments
should be used as a basis for defining adaptation actions to be
implemented in appropriate plans and strategies.
Some of the grant awards were to regional planning bodies in areas
most vulnerable to flooding and extreme weather conditions: the South
Florida Regional Planning Council (Hollywood, Florida), the Houston-
Galveston Area Planning Council and the Gulf Regional Planning Council
(Gulfport, Mississippi). The goal of these grants is not just to
develop plans--it is to articulate a vision for growth tailored to
specific metropolitan markets that federal housing, transportation, and
other federal investments can support.
Funding to these metropolitan regions and rural communities can be
used to support the development of integrated, state-of-the-art
regional development plans that use the latest data and most
sophisticated analytic, modeling, and mapping tools available.
In addition to these regional sustainability grants, HUD
collaborated with DOT to award another $75 million in Community
Challenge grants for local communities to initiate innovative housing,
transportation, rural development and urban revitalization initiatives
that are also likely to yield lower carbon emissions in these
communities.
These efforts will benefit urban, suburban and rural communities
alike. The 2007 American Housing Survey estimates that nearly 50
percent of people who live in rural places today live within the
boundaries of metropolitan statistical areas. This requires a level of
integrated planning that spans jurisdictional boundaries in new and
unprecedented ways.
Energy Efficiency and Green Building
Another important component of HUD's work to support sustainable
communities is in the area of energy efficiency and green building.
Properly implemented and maintained, relatively modest investments in
energy retrofit improvements can significantly reduce energy use in
existing buildings, as well as improve comfort for residents.\12\
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\12\ Hendricks, Goldstein, Detchon and Shickman, Rebuilding
America: A National Policy Framework for Investment in Energy
Efficiency Retrofits, Center for American Progress (August 2009). In
the residential sector, investments of $5,000 to $20,000 per unit can
achieve energy savings of 20--40 percent on average. In commercial
properties, investments of $10 to $30 per square foot can deliver
energy savings of up to 40 percent.
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HUD itself spends more than $5 billion on utilities in public
housing and other federally-assisted and public housing, and is taking
steps to lower energy consumption in this stock, which houses some of
our more vulnerable populations, including the elderly.
Through the Recovery Act, we have invested heavily in energy
efficiency in housing, including, for example through the Green
Retrofit Program, which has provided grants and loans to owners of
privately-owned multifamily buildings. Average expenditure will be
approximately $10,000 per unit, and we expect to retrofit some 20,000
units through the program.
In addition, significant investments have been made in public
housing. Through the Recovery Act, 1,500 new units will be built to
green standards or achieve the Energy Star for New Homes and another
35,000 units of public housing should lower energy use by at least 20
percent \13\. We also provide incentives for public housing authorities
to utilize third-party Energy Performance Contracts, and plan to
retrofit another 15,000 units through this mechanism over the next two
years. We have also established a partnership with the Department of
Energy to lower barriers to the use of DOE's Weatherization Assistance
Program in housing stock supported by HUD.\14\
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\13\ U.S. Department of Housing and Urban Development Capital Fund
Recovery Competition Grants, Notice of Funds Availability, May, 2009.
\14\ See www.hud.gov/recovery/weatherization.
Interagency Climate Change Adaptation Task Force and the Federal Role
The same level of interagency cooperation that underlies the
Partnership for Sustainable Communities and our partnership with DOE to
improve the energy efficiency of our buildings is now shaping federal
actions to address climate adaptation and resilience. Last month, the
Interagency Climate Change Adaptation Task Force, of which HUD is a
member, submitted a report to the President emphasizing the importance
of this issue to the Federal government.
The Task Force began meeting in the Spring, 2009. It is co-chaired
by the Council on Environmental Quality (CEQ), the National Oceanic and
Atmospheric Administration (NOAA), and the Office of Science and
Technology Policy (OSTP.) Recognizing the important role of the Federal
Government in adaptation, President Obama signed an Executive Order on
October 5, 2009 that called on the Task Force to recommend how the
policies and practices of Federal agencies can be made compatible with
and reinforce a national climate change adaptation strategy. The
Executive Order charged the Task Force with delivering a report through
the Chair of the CEQ to the President within one year.
The Task Force's Report to the President reiterated the scientific
consensus that climate change is a scientific fact, and that human
activities are a major contributing factor. It re-affirmed the
Administration's commitment to both take steps to mitigate greenhouse
gas emissions, as well as develop adaptation strategies to enable
communities to withstand and respond to the effects of climate change:
There is scientific consensus that the Earth is warming due to
increased concentrations of greenhouse gases (including carbon
dioxide) in the atmosphere (IPCC 2007, GCCI 2009, NRC 2010).
Increased energy trapped in the atmosphere and the oceans due
to these higher concentrations of greenhouse gases is already
leading to impacts, in the United States and globally,
including warmer average water and air temperatures.
The Obama Administration is committed to mitigating (i.e.,
reducing) greenhouse gas emissions to minimize the future
impacts of climate change. However, the climate impacts we are
observing today will continue to increase, at least in the
short-term, regardless of the degree to which greenhouse gas
emissions are managed. Even under lower emissions scenarios,
global average temperatures are predicted to rise by over 2+F
over the next 100 years (Figure 2) due to factors such as the
long-lived nature of certain greenhouse gases in the atmosphere
and the absorption of heat by the Earth's oceans. In the long-
term, the ability to manage greenhouse gas emissions and
moderate or reduce atmospheric concentrations of greenhouse
gases will affect the magnitude of the impacts that we will
need to adapt to (NRC 2010). Therefore, mitigation and
adaptation are inextricably linked, and both are required in
order to reduce the impacts of climate change.\15\
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\15\ Council on Environmental Quality, Progress Report of the
Interagency Climate Change Adaptation Task Force: Actions and
Recommendations In Support of a National Climate Change Adaptation
Strategy, October 5, 2010.
The Federal Role
The Task Force found that the Federal Government has an important
and unique role in climate adaptation--but it is only one part of the
broader effort that must be supported by multiple levels of government
and various other private and non-governmental partners throughout the
country.
In particular, ``Federal leadership, guidance, and support are
vital to empowering others to act and to enabling decisions based on
the best available information and science. Just as importantly, the
Federal Government can learn from and build off the efforts of others,
as many cities and states within and outside the United States have
already begun to implement adaptive measures.''
The Task Force also acknowledged that the Federal Government has an
important stake in adaptation because climate change directly affects a
wide range of Federal services, operations and programs, particularly
those associated with management of public lands, infrastructure, and
national security, among others.
The Task Force recommended in its Progress Report that Federal
Agencies make adaptation a standard part of strategic planning to
ensure that resources are invested wisely and that Federal programs,
services and operations remain effective in a changing climate.
The Task Force also recommended that the Government continue to
enhance climate services that enable informed decisions based on the
best available science, and to work with the international community to
improve knowledge sharing and coordinate adaptation investments.
We also need to pay more attention to the unintended consequences
of policies that may increase our vulnerability to climate risks and
thus make adaptation more costly and difficult; for example, certain
policies may lead to high risk activities in the very areas that
climate science would suggest people avoid.
The Interagency Task Force adopted a set of Climate Adaptation
Principles (see Attachment A), as well as five Policy Goals that we
hope will shape federal action in this arena. In addition, we expect to
initiate a number of pilot projects where these principles and goals
can be tested in partnership with local communities.
Thank you Mr. Chairman, and members of the Committee--I look
forward to answering your questions.
Attachment A: Federal Interagency Task Force Climate Adaptation
Principles
Adopt integrated approaches. Climate change preparation and
response should be integrated into core policies, planning, practices,
and programs whenever possible.
Prioritize the most vulnerable. Adaptation plans should prioritize
helping people, places, and infrastructure that are most vulnerable to
climate impacts. They should also be designed and implemented with
meaningful involvement from all parts of society. Issues of inequality
and environmental justice associated with climate change impacts and
adaptation should be addressed.
Use best-available science. Adaptation should be grounded in best-
available scientific understanding of climate change risks, impacts,
and vulnerabilities. Adaptive actions should not be delayed to wait for
a complete understanding of climate change impacts, as there will
always be some uncertainty. Plans and actions should be adjusted as our
understanding of climate impacts increases.
Build strong partnerships. Adaptation requires coordination across
multiple sectors, geographical scales, and levels of government and
should build on the existing efforts and knowledge of a wide range of
stakeholders. Because impacts, vulnerability, and needs vary by region
and locale, adaptation will be most effective when driven by local or
regional risks and needs.
Apply risk-management methods and tools. A risk management approach
can be an effective way to assess and respond to climate change because
the timing, likelihood, and nature of specific climate risks are
difficult to predict. Risk management approaches are already used in
many critical decisions today (e.g., for fire, flood, disease
outbreaks), and can aid in understanding the potential consequences of
inaction as well as options for risk reduction.
Apply ecosystem-based approaches. Ecosystems provide valuable
services that help to build resilience and reduce the vulnerability of
people and their livelihoods to climate change impacts. Integrating the
protection of biodiversity and ecosystem services into adaptation
strategies will increase resilience of human and natural systems to
climate and non-climate risks, providing benefits to society and the
environment.
Maximize mutual benefits. Adaptation should, where possible, use
strategies that complement or directly support other related climate or
environmental initiatives, such as efforts to improve disaster
preparedness, promote sustainable resource management, and reduce
greenhouse gas emissions including the development of cost-effective
technologies.
Continuously evaluate performance. Adaptation plans should include
measurable goals and performance metrics to continuously assess whether
adaptive actions are achieving desired outcomes. In some cases, the
measurements will be qualitative until more information is gathered to
evaluate outcomes quantitatively. Flexibility is a critical to building
a robust and resilient process that can accommodate uncertainty and
change.
Attachment B: Federal Interagency Task Force Policy Goals
Encourage and mainstream adaptation planning across the Federal
Government.
Improve integration of science into decision making.
Address key cross-cutting issues.
Enhance efforts to lead and support international adaptation.
Align and coordinate capabilities of the Federal Government to support
national adaptation.
Biography for James C. Lopez
James (Jim) Lopez is the Senior Advisor to Deputy Secretary Ron
Sims at the Department of Housing and Urban Development. Under the
Deputy Secretary's Office, he has played a leading role in creating and
implementing several of HUD's interagency initiatives including HUD's
work on sustainable and livable communities, climate change adaptation,
and energy efficiency.
Before joining HUD, Jim served in various senior advisor positions
for King County in Seattle, Washington. Of note, he was the Director of
Strategic Planning and Performance Management in the office of King
County's former Executive Ron Sims. He also served as Executive Sims'
Deputy Chief of Staff and key policy strategist. Jim led King County's
internationally recognized Climate Change program and helped create the
county's award winning Health Reform Initiative.
Prior to his entry into government, Jim practiced law for nine
years in Boston, Massachusetts.
Jim received a law degree from Case Western Reserve in 1992 and a
M.P.A. from Harvard University's John F. Kennedy School of Government
in 2003. He resides in Gaithersburg, MD with his wife and two
daughters.
Chairman Baird. Thank you, Mr. Lopez.
Mr. Geer.
STATEMENT OF WILLIAM GEER, DIRECTOR OF THE CENTER FOR WESTERN
LANDS, THEODORE ROOSEVELT CONSERVATION PARTNERSHIP
Mr. Geer. Thank you, Mr. Chairman.
We appreciate the opportunity to sit before this committee
and share the concerns we have on climate change and recite
what we are doing about it, what we see in the field, what we
are doing about it today.
I have no PowerPoint slides, but I represent a community of
people, both professionally and in terms of passionate views,
that have a great concern about what's happening in
environmental change.
Professionally, I represent fish and wildlife biologists. I
have been one for 38 years, and so I have had a chance to work
on a lot of impacts and a lot of development projects, and I
have seen changes. I don't always know the causes of all those
changes, but the people in my field always have to deal with
the consequences and manage accordingly, even if we can't
always decide where exactly did that change come from.
In terms of the passionate users, I represent hunters and
anglers. Many of these hunters and anglers are not scientists.
Some in fact are; most are not. But they have a passion for use
of the resource, and we often feel that they also are some of
the first observers of change in the field. They see things in
a natural environment because it affects the distribution of
animals, or perhaps they pursue hunting and fishing, and of
course they want us to do something about it.
I live in Montana, where about half the population actually
hunts and fishs. Twenty percent still hunt, and about half of
them hunt or fish. And that's a sustainable outdoor recreation
economy, in a state of less than a million people, of over a
billion dollars a year. It's economically pretty significant.
And I meet frequently with these sportsmen in more than 32
cities scattered around the state on a regular basis. I talk
about many conservation issues, climate change being one. And
what I have found over the past few years in talking about
climate change is, while some sportsmen won't utter the words
climate change--it's partisan right now and it's almost a toxic
phrase--most of them will readily acknowledge that the shorter
winters, reduced snow pack, increasing spring rainfall, lower
stream flows, melting glaciers, and mountain pine beetle
epidemic reflect an environmental change that does not bode
well for fish and wildlife or hunting and fishing as
recreational activities.
As a consequence, in 2008, nine of the Nation's leading
hunting and fishing conservation organizations released a book
called Seasons' End, a report predicting the impacts of climate
change on fish and wildlife habitat and its implications for
sustainable hunting and fishing, and some of the conclusions
are based on the best available predictions from scientists.
We heard earlier that upland birds face disruptions in life
cycles that will sever reproduction and the emergence of
critical food resources. In cold, wet springs, young birds
sometimes suffer fatal exposure to cold from loss of thermal
snow cover. Reduced nesting success leading to losses in
specific age classes and eventually to population instability,
coupled with increased predation and an influx of invasive
species, result in fewer birds in the hunters' bags.
In Montana, though, we have some complications. Because
climate change isn't the only stressor on the landscape. We
find that sage grouse declines have also been tied to natural
gas drilling disturbance too close to leks and brood rearing
areas. So we have to integrate many sources of stress on a
resource and try to manage around them and be successful.
There are species like mountain goats and bighorn sheep
that have a much more narrowly defined habitat and are much
more sensitive to a changing climate. They will have to compete
for increasingly isolated, fragmented, and diminished habitat.
Rising temperatures in the Rockies potentially will allow trees
and shrubs to overwhelm sagebrush ecosystems that now provide
desirable winter forage for pronghorn, elk, and mule deer; and
big game hunters in Montana are already having less success
because winter snows are arriving later in the fall, keeping
elk and mule deer at a higher elevation and less accessible
areas for most of the hunting season.
It's not just a matter of we enjoy hunting. Hunting is a
necessary management tool. If you are in the business of
managing wildlife, many of our hunts are based on population
management and migrations downhill into areas where people can
get to provide the hunting necessary for herd size management.
Shorter winters will affect the availability of waterfowl
food and cover and quality of habitat. Longer ice-free seasons
will lead to changes in migratory timing, routes, and wintering
locations. Sea level rise on the coasts certainly will inundate
coastal wetlands and squeeze waterfowl into narrowing bands of
habitat. And the prairie pothole region, of which Montana is
part, could lose up to 90 percent of its wetlands--small
wetlands to climate change and reducing the region's breeding
ducks by as much as 69 percent in an area that we call
America's duck breeding factory. Hunters throughout the country
now report that waterfowl migrations are occurring later in the
season and in some cases not occurring at all.
Warming waters will slow trout growth rates, increase
stress and susceptibility to toxins, parasites, and disease.
Trout will be forced to congregate in constricted habitats and
compete with invasive species.
Nonnative smallmouth bass have already moved 40 river miles
upstream in the Yellowstone River, displacing Yellowstone
cutthroat trout, a very cold water species, because of warming
water. The physical habitat was there, but now the water's
warmed up. There is lower June runoff, lower August
precipitation, lower August flows. Water warms up, we change
the species mix.
Declining stream flows with less snow pack have already
decimated fishing opportunities in some western states, where
trout populations could be reduced by up to 50 percent. Trout
fishing spots and success will change significantly, and mostly
not for the better.
Climate change could fundamentally change the participation
rates of America's 13 million hunters and 28 million freshwater
anglers. As fish and wildlife habitat, abundance, and
distribution shift in response to a changing climate, patterns
of recreational activities will shift as well. The loss of big
game and upland bird hunting opportunities in Idaho, Montana,
and Wyoming in the northern Rockies would impair a sustainable
recreational economy that currently supports more than 4.3
million hunter days annually and generates more than $3.45
billion annually in economic value. Nationally, outdoor
recreation, including hunting and fishing activities,
contribute 6.5 million jobs, which are pretty necessary in
today's economy, and a total economic value of $725 billion per
year.
We have another new report now. It's not just a matter of
reporting impacts, but it's what are we going to do about it?
We are in the business of doing adaptive management; and we
have presented ideas and adaptation strategies which we
distributed in a book called Beyond Seasons' End yesterday to
the committee in which we identify candidate types of
strategies and projects that we could do, along with the likely
costs, to help alleviate and ameliorate the effects of climate
change.
There is going to be species that win and species that
lose. We can't change the climate necessarily. We are not the
greenhouse gas emission experts. What we specialize in is how
do we adapt to what's left.
The report gives numerous examples of what can be done on
the ground, real-world stuff to restore and protect crucial
habitat for waterfowl, warm and cold water fisheries, big game
and upland birds and saltwater fish and to secure connective
corridors between habitats, allocate water for sport fish,
adjust population management and harvests and develop state and
national adaptation plans.
We already have some mechanisms that you fund through
Congress called state wildlife grants, state wildlife action
plans--they are now at landscape level--that will help become
fundamental tools for managing landscapes of changing
environment in the field. We estimate that the cost of such an
adaptational plan nationally is likely at the start to be in
the neighborhood of, nationwide, at $1 to $3 billion a year.
But we think that the consequences of not taking action now
are going to be much more expensive in the future. It will have
economic consequences to the economy, and certainly the quality
of living for our children and grandchildren are going to be
affected.
I have one statement I would like to make, one sentence I
thought was pertinent that economists made back in March, not
biologists like me. I think it reflects today's attitude
somewhat: Action on climate is justified not because the
science is certain, but precisely because it is not.
Thank you.
[The prepared statement of Mr. Geer follows:]
Prepared Statement of William H. Geer
I want to thank the chairman and members of the committee for the
opportunity to present testimony on this important issue.
I live in Montana, where 20 percent of the population hunts and
fishes, supporting a sustainable outdoor recreation economy exceeding a
billion dollars every year. In fact, the hunting-and-fishing economy in
Montana is at least as big as the state's energy economy. A bumper
sticker recently spotted in Montana said, ``Hunting is not matter of
life or death--it's much more important than that.'' Needless to say,
we place great value on our sporting traditions in the Treasure State.
I meet frequently with sportsmen across Montana and have traveled
to rod and gun clubs in 32 towns throughout the state to discuss
climate change and its impacts on fish and wildlife. Sportsmen tell me
that they both feel and see the effects of the average air temperature
increase of 2.3 degrees Fahrenheit that has occurred since 1951. They
are observing delayed onset of winter conditions, a snowpack that has
declined 17 percent over the past 60 years and spring rainfall amounts
that have increased nearly 6 percent. They also are experiencing late
summer precipitation that has declined more than 20 percent and flows
in coldwater streams that are declining noticeably throughout Montana.
They realize that the glaciers in Glacier National Park are likely to
disappear by 2030 (at this time, only 26 remain of the 150 that existed
in 1850). And, finally, they see that Montana's warmer winters and
drier summers have allowed the mountain pine beetle to expand its
natural infestation of Montana's lodgepole pine forests to epidemic
levels, resulting in 2 million acres of beetle-killed trees.
While some of these sportsmen might never utter the words ``climate
change,'' they readily acknowledge that the later and shorter winters,
reduced snowpack, increasing spring rain, lower streamflows, melting
glaciers and widespread pine beetle epidemic reflect an environmental
change that is beyond rational debate. They also know that this
magnitude of environmental change will eventually result in serious
declines in many species of fish and wildlife. Global climate change
does not bode well for the future of fish and wildlife and recreational
hunting and fishing.
The Theodore Roosevelt Conservation Partnership's fundamental
beliefs regarding climate change are
Global climate change is real.
Sportsmen likely will be the first to experience the
repercussions of climate change.
We need to safeguard fish and wildlife resources from
climate change with adaptation strategies.
How we address global climate change now will dictate
whether future generations will continue to enjoy sporting
traditions.
In 2008, the Wildlife Management Institute and eight of the
nation's leading hunting and fishing organizations released Seasons'
End: Global Warming's Threat to Hunting and Fishing
(www.seasonsend.org), a report detailing the predicted impacts of
climate change on fish and wildlife habitat and its implications for
sustainable hunting and fishing. Some of the report's conclusions
follow.
Upland birds face a severe future as climate change progresses.
Disruptions in life cycles likely will sever reproduction and the
emergence of critical food sources. Young birds could suffer fatal
exposure to winter cold from loss of thermal snow cover, with reduced
nesting success and increased predation leading to major population
reductions. These declines coupled with an influx of invasive species
will result in fewer birds in the hunters' bags. Increasing droughts
could devastate food sources for upland birds, with prairie chickens,
sage grouse, sharp-tailed grouse and pheasants among the species most
likely to be diminished in number. Many eastern Montana ranchers
consider the prime prairie grouse and pheasant hunting on their lands
to be an important cash crop, along with cattle and wheat.
Big game likely will be adversely impacted in several ways.
Mountain goats and bighorn sheep will compete for increasingly
isolated, fragmented and diminished habitat. Rising temperatures in the
Rocky Mountains will allow trees and shrubs to overwhelm sagebrush
ecosystems that in the past provided desirable winter forage for
pronghorn, elk and mule deer. As fragmentation and loss of critical
winter range continues, mule deer and elk could dwindle in numbers,
particularly in Montana, Wyoming, Utah, Colorado and New Mexico. Forage
becomes less nourishing in prolonged droughts, and elk and mule deer
are likely to remain at higher elevations longer. Big-game hunters in
Montana already are having less success because winter snows are
arriving later in the fall, keeping elk and mule deer at higher
elevations and in less accessible areas through most of the hunting
season.
Unlike big game, waterfowl can move quickly and cover vast
distances. Nevertheless, shorter winters will affect the availability
of waterfowl food and cover and quality of habitat. Longer ice-free
seasons will lead to changing migratory timing, routes and wintering
locations. Sea level rise inundating coastal wetlands will squeeze
waterfowl into narrowing bands of habitat. The prairie pothole region,
which includes portions of Iowa, Minnesota, Montana and the Dakotas,
could lose up to 90 percent of its wetlands to climate change, reducing
the region's breeding ducks by as much as 69 percent in an area often
called North America's duck breeding factory. No species can withstand
the loss of 90 percent of its critical habitat base. Hunters throughout
the United States report that waterfowl migrations are occurring later
in the season and, in some cases, not occurring at all.
The outlook for trout in the West is warming water that will slow
trout growth rates, increase stress and increase susceptibility to
toxins, parasites and disease. Trout will be forced to congregate in
constricted habitats and compete with invasive species. Diminishing
streamflows from declining snowpack already have decimated trout
populations and fishing opportunities in some Montana streams, such as
Lolo Creek south of Missoula where low flows have reduced once-thriving
populations of cutthroat, rainbow, brown and brook trout. Western trout
populations could be reduced by 50 percent. Trout fishing spots and
success will change significantly--and not for the better.
Global climate change has the power to fundamentally change the
participation rates of America's 13 million hunters and 28 million
freshwater anglers, as well as the geography of hunting and fishing in
North America. As fish and wildlife habitat, abundance and distribution
shift in response to a changing climate, patterns of recreational
activities will shift as well. Today's carefully delineated protected
areas may not even be encompassed within the new habitat zones where
the mobile species of wildlife may be forced to migrate under a
changing climate.
Collectively, Idaho, Montana and Wyoming still harbor the finest
hunting for big game and upland bird and trout fishing resources in the
country. The loss of big game and upland gamebird hunting opportunities
in these northern Rocky Mountain states would impair what has been a
sustainable recreational economy that currently supports more than 4.3
million hunter-days annually and annually generates more than $3.45
billion in total economic value (Backcountry Bounty, Sonoran Institute,
June 2006).
Now, Beyond Seasons' End (www.seasonsend.org), a new report
released in 2010 by 10 of the nation's leading hunting and fishing
organizations, along with the TRCP, presents adaptation strategies,
measures and costs to aid fish and wildlife in adapting to global
climate change. The common-sense and science-based recommendations that
are spelled out and ``cost out'' in Beyond Seasons' End are well-
conceived, field-tested and can be accomplished if funding can be
provided. This application of science shows what can be done on the
ground to restore and protect crucial fish and wildlife habitat, secure
migration corridors and connectivity between habitats, allocate water
for sport fish and develop regional and national adaptation plans.
A number of state fish and wildlife agencies are in the process of
revising their state wildlife action plans (funded largely by State
Wildlife Grant appropriations from Congress) to incorporate
comprehensive strategies for fish and wildlife adaptation to climate
change. The state wildlife action plans, when based on landscape-level
habitat management and conservation, will become one of the fundamental
tools of state agencies for improving the resiliency and sustainability
of fish and wildlife under a changing climate, particularly when they
are developed in concert with neighboring states that share the habitat
ranges and connective corridors for wildlife that do not recognize
political borders.
The Montana Department of Fish, Wildlife & Parks is updating its
comprehensive fish and wildlife conservation strategy to include
adaptive measures to better sustain and manage fish and wildlife across
broad landscapes in a changing climate, using strategies presented in
Beyond Seasons' End. The revised strategy will emphasize crucial areas,
such as new areas of winter range for elk, and corridors that will
enable mobile fish and wildlife species to move to suitable habitat.
The agency's new Crucial Areas Planning System integrates many computer
databases that provide wildlife managers with the physical, biological
and social information to better predict impacts of climate change and
development on fish and wildlife--and hunting and fishing--and develop
more effective mitigation and adaptive management measures.
The Yellowstone River Strategy is one example of the landscape-
level approaches identified by Montana Fish, Wildlife & Parks and a
working group comprised of non-agency specialists to help Yellowstone
cutthroat trout survive in a warming river environment. The June runoff
and late summer flows have been declining since the early 1950s, and
the water now is favoring smallmouth bass over cutthroats. The main
factors behind a decline in Yellowstone cutthroat trout in the
Yellowstone River have been contraction of coldwater habitats in upper
reaches, increasing temperatures and loss of connectivity from reduced
flows in lower reaches, loss of tributary connectivity from reduced
flows and diversion dams and a decline of Yellowstone cutthroat trout
with encroaching smallmouth bass upstream to Reed Point. The
Yellowstone River System strategy would safeguard genetically pure
Yellowstone cutthroat trout by conserving their strongholds in
headwater tributaries; constructing temporary, high-elevation water
storage to augment downstream flows in the summer; re-establishing
stream connectivity to allow fish to disperse in mid-elevation
downstream reaches; removing fish passage barriers and restoring
riparian areas, wet meadows and wetlands in lower-elevation downstream
reaches while maintaining the prime coldwater fishing opportunities for
which the river is famous.
Another example of a Montana Fish, Wildlife & Parks landscape-level
climate adaptation project is the Sagebrush Steppe System Initiative in
southwestern and eastern Montana. The sagebrush habitat community
provides critical habitat to many of the big-game, waterfowl and upland
bird species prized by hunters. These are the likely effects of climate
change on these species in the sagebrush steppe area: elk, mule deer
and pronghorn overwinter survival might improve with milder winters,
but recruitment to the population likely will decline due to forage
nutritional deficiencies; Greater sage-grouse are likely to be hurt by
the declining extent and density of sagebrush for food and shelter; and
waterfowl likely will decline from drier climate and loss of small
wetlands.
In the Sagebrush Steppe System Initiative, Montana Fish, Wildlife &
Parks more closely coordinates with agencies, namely the U.S. Forest
Service and Bureau of Land Management, which manage the majority of
Montana's publicly owned habitat and which now are required to consider
impacts of their management on the climate. Also, the agency will work
closely with private agricultural landowners using private-land
conservation incentives in the 2008 Farm Bill, such as the Conservation
Stewardship, Environmental Quality Incentives and Farm and Ranchland
Protection programs. Conserving and maintaining crucial areas and
migratory corridors will receive special emphasis.
As Congress develops climate and energy legislation, I urge you to
ensure that such legislation establishes a national program to mitigate
the causes of global warming by reducing emissions of greenhouse gases
and sequestering carbon from the atmosphere.
The unavoidable adverse effects of climate change on fish and
wildlife and their habitats may be minimized or prevented in some cases
through adaptation measures and management actions initiated at the
earliest time possible. There is a compelling and urgent need for fish
and wildlife managers to initiate specific conservation actions--such
as ensuring crucial habitat availability and connectivity--that would
help fish and wildlife maintain self-sustaining populations through an
ongoing flexible management process of adaptive management.
Specifically, a House bill should establish a national policy framework
to help protect, reconnect and restore public and private lands;
provide increased scientific capacity; identify wildlife migration
corridors; coordinate and share information; and dedicate a sufficient
amount of funding to federal, state and tribal agencies to implement
identified actions needed assure the resiliency and sustainability of
our fish and wildlife resources.
The activities of the federal resource agencies needed to restore
and protect fish and wildlife from the impacts of climate change should
be directed and coordinated through a comprehensive national strategy,
developed in close consultation with states, tribes and other
stakeholders and with advice from the National Academy of Sciences and
a science advisory board.
The activities of the state resource agencies should be directed
and coordinated through individual, state-based, comprehensive
strategies for fish and wildlife adaptation to climate change that are
approved by the Secretary of the Interior and integrated into state
wildlife action plans, state coastal zone management plans and other
state wildlife species or habitat plans. Opportunities should be
provided for scientific and public input during the development and
implementation of these strategies.
Most sportsmen pay homage to President Theodore Roosevelt because
he had the courage and foresight to advance a strong conservation
agenda and restore depleted fish and wildlife against a political tide,
bequeathing to us the rich fish and wildlife heritage sportsmen cherish
to this day. Roosevelt had the foresight to recognize that Congress
must take action at a critical time to safeguard this legacy for future
generations of Americans. For the sake of our children and
grandchildren, we now must act at what is another critical time. While
no one has all the answers to the challenge of climate change, we know
we are dealing with a rapidly changing world. We must step up today to
do the conservation work that will ensure the future--not only of
hunting and fishing, but of our very quality of life.
Thank you.
Biography for William H. Geer
William Geer joined the TRCP staff full time in 2005 as policy
initiatives manager. After earning a bachelor of science from the
University of Montana School of Forestry and a master of science in
limnology from Montana State University, Bill has spent the past 38
years as a professional fish and wildlife conservationist. Before
joining the TRCP, he served as the director of the Utah Division of
Wildlife Resources, coordinator for the North American Waterfowl
Management Plan for the National Fish and Wildlife Foundation, vice
president for both field operations and conservation programs for the
Rocky Mountain Elk Foundation, Inland Northwest conservation manager
for the Nature Conservancy in Idaho and executive director of the
Outdoor Writers Association of America.
Chairman Baird. Thank you, Mr. Geer.
Dr. Curry.
STATEMENT OF JUDITH A. CURRY, CHAIR OF THE SCHOOL OF EARTH AND
ATMOSPHERIC SCIENCES, GEORGIA INSTITUTE OF TECHNOLOGY
Dr. Curry. I would like to--Hello? Okay.
I would like to thank the Chairman and the Committee for
the opportunity to participate in this hearing.
You have heard forceful arguments from climate scientists
for a looming future threat from anthropogenic climate change.
Anthropogenic climate change is a theory whose basic mechanism
is well understood but whose magnitude is highly uncertain.
This conflict regarding this theory is over the level of our
ignorance regarding what is known about natural climate
variability, about what is unknown about natural climate
variability, and the feedback processes.
Based on the background knowledge that we have, the threat
from global climate change does not seem to be an existential
one on the time scale of the 21st century, even in its most
alarming incarnation. It seems more important that robust
policy responses be formulated than to respond urgently with
policies that may fail to address the problem and whose
unintended consequences have not been adequately explored.
How to deal with this complex problem presents many
challenges at the interface between science and policy. Over
the past 20 years, scientists have become entangled in an
acrimonious scientific and political debate where the issues in
each have become confounded. Debates over relatively arcane
aspects of the scientific argument have become a substitute for
what should be a real debate about politics and values.
I have been publicly raising concerns since 2003 about how
uncertainty surrounding climate change is evaluated and
communicated. At this point, it seems more important to explore
the uncertainties associated with future climate change, rather
than to attempt to reduce the uncertainties in a consensus-
based approach.
It's time for climate scientists to change their view of
uncertainty. It's not just something that is merely to be
framed and communicated to policymakers while mindful that
doubt is a political weapon in the decision-making process.
Characterizing, understanding, and exploring uncertainty is at
the heart of the scientific process; and, further, the
characterization of uncertainty is critical information for
robust policy decisions.
It's important to broaden the scope of global climate
change research to develop a better understanding of natural
climate variability and the impact of land use changes; and far
more attention needs to be given to establishing robust and
transparent climate data records, particularly the paleoclimate
record. Regional planners and resource managers want accurate,
high-resolution climate model projections to support local
climate adaptation plans and climate-compatible development.
The need for such models is unlikely to be met at least in the
short term.
In any event, anthropogenic climate change on time scales
of decades is arguably less important in driving vulnerability
than increasing population, land use practices, and ecosystem
degradation. Regions that find solutions to current problems of
climate variability and extreme weather events and address
challenges associated with an increasing population will be
better prepared to cope with any additional stresses from
climate change.
Climate researchers need to engage with regional planners,
economists, military intelligence organizations, development
banks, energy companies, and governments in the developing
world. Such engagement can develop a mutual understanding about
what kind of information is needed, promote more fruitful
decision outcomes, and to find new scientific challenges to be
addressed by research.
The need for climate researchers to engage with social
scientists and engineers has never been more important, and
there is an increasing need for social scientists and
philosophers of science to scrutinize and analyze our field to
prevent dysfunction at the science-policy interface, which has
been so evident this past year.
Climate scientists and the institutions that support them
need to acknowledge and engage with ever-growing groups of
citizens, scientists, and extended peer communities that have
become increasingly well organized by the blogosphere. The more
sophisticated of these groups are challenging our conventional
notions of expertise and are bringing much-needed scrutiny
particularly into issues surrounding historical and
paleoclimate data records. These groups reflect the growing
public interest in climate science and a growing concern about
possible impacts of both climate change and climate change
policies.
And, further, this interest has illuminated the fundamental
need for improved and transparent historical and paleoclimate
data sets and improved information systems so that these data
are easily accessed and interpreted. We need to identify and
secure the common interests in dealing with the climate,
energy, and ocean acidification problems.
A diversity of views on interpreting the scientific
evidence and a broad range of ideas on how to address these
challenges doesn't hinder the implementation of diverse,
bottom-up solutions. Securing the common interest on local and
regional scales provides a basis for the successful
implementation of climate adaptation strategies and successes
on the regional scale and then national scale make it much more
likely that global issues can be confronted in an effective
way.
Thank you.
[The prepared statement of Dr. Curry follows:]
Prepared Statement of Judith A. Curry
I thank the Chairman and the Committee for the opportunity to offer
testimony today on ``Rational Discussion of Climate Change.'' I am
Chair of the School of Earth and Atmospheric Sciences at the Georgia
Institute of Technology. As a climate scientist, I have devoted 30
years to conducting research on a variety of topics including climate
feedback processes in the Arctic, energy exchange between the ocean and
the atmosphere, the role of clouds and aerosols in the climate system,
and the impact of climate change on the characteristics of hurricanes.
As president of Climate Forecast Applications Network LLC, I have been
working with decision makers on climate impact assessments, assessing
and developing climate adaptation strategies, and developing
subseasonal climate forecasting strategies to support adaptive
management and tactical adaptation. Over the past year, I have been
actively engaging with the public (particularly in the blogosphere) on
the issue of integrity of climate science, and also the topic of
uncertainty.
The climate change response challenge
Climate change can be categorized as a ``wicked problem.'' \1\
Wicked problems are difficult or impossible to solve, there is no
opportunity to devise an overall solution by trial and error, and there
is no real test of the efficacy of a solution to the wicked problem.
Efforts to solve the wicked problem may reveal or create other
problems.
---------------------------------------------------------------------------
\1\ Rittel, Horst, and Melvin Webber; ``Dilemmas in a General
Theory of Planning,'' pp. 155-169, Policy Sciences, Vol. 4, Elsevier
Scientific Publishing Company, Inc., Amsterdam, 1973. http://
www.uctc.net/mwebber/
Rittel+Webber+Dilemmas+General-Theory-of-
Planning.pdf
---------------------------------------------------------------------------
The United Nations Framework Convention on Climate Change (UNFCCC)
and the Intergovernmental Panel on Climate Change (IPCC) have framed
the climate change problem (i.e. dangers) and its solution (i.e.
international treaty) to be irreducibly global. Based upon the
precautionary principle, the UNFCCC's Kyoto Protocol has established an
international goal of stabilization of the concentrations of greenhouse
gasses in the atmosphere. This framing of the problem and its solution
has led to the dilemma of climate response policy that is aptly
described by Obersteiner et al. \2\:
---------------------------------------------------------------------------
\2\ http://helda.helsinki.fi/bitstream/handle/1975/292/2001-
Managing-climate-risk.pdf?sequence=1
The key issue is whether ``betting big today'' with a
comprehensive global climate policy targeted at stabilization
``will fundamentally reshape our common future on a global
scale to our advantage or quickly produce losses that can throw
---------------------------------------------------------------------------
mankind into economic, social, and environmental bankruptcy.''
In a rational discussion of climate change, the question needs to
be asked as to whether the framing of the problem and the early
articulation of a preferred policy option by the UNFCCC has
marginalized research on broader issues surrounding climate change, and
resulted is an overconfident assessment of the importance of greenhouse
gases in future climate change, and stifled the development of a
broader range of policy options.
The IPCC/UNFCCC have provided an important service to global
society by alerting us to a global threat that is potentially
catastrophic. The UNFCCC/IPCC has made an ambitious attempt to put a
simplified frame around the problem of climate change and its solution
in terms of anthropogenic forcing and CO2 stabilization
polices. However, the result of this simplified framing of a wicked
problem is that we lack the kinds of information to more broadly
understand climate change and societal vulnerability.
Uncertainty in climate science
Anthropogenic climate change is a theory in which the basic
mechanism is well understood, but in which the magnitude of the climate
change is highly uncertain owing to feedback processes. We know that
the climate changes naturally on decadal to century time scales, but we
do not have explanations for a number of observed historical and paleo
climate variations, including the warming from 1910-1940 and the mid-
20th century cooling. The conflict regarding the theory of
anthropogenic climate change is over the level of our ignorance
regarding what is unknown about natural climate variability.
I have been raising concerns \3\ since 2003 about how uncertainty
surrounding climate change is evaluated and communicated. The IPCC's
efforts to consider uncertainty focus primarily on communicating
uncertainty, rather than on characterizing and exploring uncertainty in
a way that would be useful for risk managers and resource managers and
the institutions that fund science. A number of scientists have argued
that future IPCC efforts need to be more thorough about describing
sources and types of uncertainty, making the uncertainty analysis as
transparent as possible. Recommendations along these lines were made by
the recent IAC \4\ review of the IPCC.
---------------------------------------------------------------------------
\3\ http://curry.eas.gatech.edu/climate/pdf/crc-102103.pdf
\4\ http://reviewipcc.interacademycouncil.net/
---------------------------------------------------------------------------
Because the assessment of climate change science by the IPCC is
inextricably linked with the UNFCCC polices, a statement about
scientific uncertainty in climate science is often viewed as a
political statement. A person making a statement about uncertainty or
degree of doubt is likely to become categorized as a skeptic or denier
or a ``merchant of doubt,'' \5\ whose motives are assumed to be
ideological or motivated by funding from the fossil fuel industry. My
own experience in publicly discussing concerns about how uncertainty is
characterized by the IPCC has resulted in my being labeled as a
``climate heretic'' \6\ that has turned against my colleagues.
---------------------------------------------------------------------------
\5\ Oreskes, N. and E.M. Conway, 2010: Merchants of Doubt: How a
Handful of Scientists Obscured the Truth on Issues from Tobacco to
Global Warming. Bloomsbury Press, 368 pp.
\6\ http://www.scientificamerican.com/article.cfm?id=climate-
heretic
Climate change winners and losers
A view of the climate change problem as irreducibly global fails to
recognize that some regions may actually benefit from a warmer and/or
wetter climate. Areas of the world that currently cannot adequately
support populations and agricultural efforts may become more desirable
in future climate regimes.
Arguably the biggest global concern regarding climate change
impacts is concerns over water resources. This concern is exacerbated
in regions where population is rapidly increasing and water resources
are already thinly stretched. China and South Asia (notably India,
Pakistan, and Bangladesh) are facing a looming water crisis arising
from burgeoning population and increasing demand for water for
irrigated farming and industry. China has been damming the rivers
emerging from Tibet and channeling the water for irrigation, and there
is particular concern over the diversion of the Brahmaputra to irrigate
the arid regions of Central China. China's plans to reroute the
Brahmaputra raises the specter of riparian water wars with India and
Bangladesh.
The IPCC AR4 WGII makes two statements of particular relevance to
the water situation in central and south Asia:
``Freshwater availability in Central, South, East and South-
East Asia . . . is likely to decrease due to climate change,
along with population growth and rising standard of living that
could adversely affect more than a billion people in Asia by
the 2050s (high confidence).'' \7\
---------------------------------------------------------------------------
\7\ http://www.ipcc.ch/publications-and-data/
ar4/wg2/en/ch10s10-es.html
``Glaciers in the Himalaya are receding faster than in any
other part of the world and, if the present rate continues, the
likelihood of them disappearing by the year 2035 and perhaps
sooner is very high if the Earth keeps warming at the current
rate. Its total area will likely shrink from the present
500,000 to 100,000 km2 by the year 2035 (WWF, 2005).'' \8\
---------------------------------------------------------------------------
\8\ http://www.ipcc.ch/publications-and-data/
ar4/wg2/en/ch10s10-6-2.html
The lack of veracity of the statement about the melting Himalayan
glaciers has been widely discussed, and the mistake has been
acknowledged by the IPCC.\9\ However, both of these statements seem
inconsistent with the information in Table 10.2 of the IPCC AR4 WG II
and the statement:
---------------------------------------------------------------------------
\9\ http://www.ipcc.ch/pdf/presentations/himalaya-statement-
20january2010.pdf
``The consensus of AR4 models . . . indicates an increase in
annual precipitation in most of Asia during this century; the
relative increase being largest and most consistent between
models in North and East Asia. The sub-continental mean winter
precipitation will very likely increase in northern Asia and
the Tibetan Plateau and likely increase in West, Central,
South-East and East Asia. Summer precipitation will likely
increase in North, South, South-East and East Asia but decrease
in West and Central Asia.'' \10\
---------------------------------------------------------------------------
\10\ http://www.ipcc.ch/
publications-and-data/ar4/wg2/en/ch10s10-
3.html#10-3-1
Based on the IPCC's simulations of 21st century climate, it seems
that rainfall will increase overall in the region (including wintertime
snowfall in Tibet), and the IPCC AR4 WGII does not discuss the impact
of temperature and evapotranspiration on fresh water resources in this
region. The importance of these omissions, inconsistencies or mistakes
by the IPCC is amplified by the potential of riparian warfare in this
region that supports half of the world's population.
A serious assessment is needed of vulnerabilities, region by
region, in the context of possible climate change scenarios,
demographics, societal vulnerabilities, possible adaptation, and
current adaptation deficits. A few regions have attempted such an
assessment. Efforts being undertaken by the World Bank Program on the
Economics of Adaptation to Climate Change to assess the economics of
adaptation in developing countries are among the best I've seen in this
regard. This is the kind of information that is needed to assess
winners and losers and how dangerous climate change might be relative
to adaptive capacities.
Climate surprises and catastrophes
The uncertainty associated with climate change science and the
wickedness of the problem provide much fodder for disagreement about
preferred policy options. Uncertainty might be regarded as cause for
delaying action or as strengthening the case for action. Low-
probability, high-consequence events in the context of a wicked problem
provide particular challenges to developing robust policies.
Extreme events such as landfalling major hurricanes, floods,
extreme heat waves and droughts can have catastrophic impacts. While
such events are not unexpected in an aggregate sense, their frequency
and/or severity may increase in a warmer climate and they may be a
surprise to the individual locations that are impacted by a specific
event. Natural events become catastrophes through a combination of
large populations, large and exposed infrastructure in vulnerable
locations, and when humans modify natural systems that can provide a
natural safety barrier (e.g. deforestation, draining wetlands). For
example, the recent catastrophic flooding in Pakistan \11\ apparently
owes as much to deforestation and overgrazing as it does to heavy
rainfall. Addressing current adaptive deficits and planning for climate
compatible development will increase societal resilience to future
extreme events that may be more frequent or severe in a warmer climate.
---------------------------------------------------------------------------
\11\ http://judithcurry.com/2010/09/20/pakistan-on-my-mind/
---------------------------------------------------------------------------
Abrupt climate change \12\ is defined as a change that occurs
faster than the apparent underlying driving forces. Abrupt climate
change, either caused by natural climate variability or triggered in
part by anthropogenic climate change, is a possibility that needs
investigation and consideration. Catastrophic anthropogenic climate
change arising from climate sensitivity on the extreme high end of the
distribution has not been adequately explored, and the plausible worst-
case scenario has not be adequately articulated. To what extent can we
falsify scenarios of very high climate sensitivity based on our
background knowledge? What are the possibilities for abrupt climate
change, and what are the possible time scales involved? What regions
would be most vulnerable under this worst-case scenario?
---------------------------------------------------------------------------
\12\ http://www.nap.edu/openbook.php?isbn=0309074347
---------------------------------------------------------------------------
Weitzmann \13\ characterizes the decision making surrounding
climate change in the following way:
---------------------------------------------------------------------------
\13\ http://dash.harvard.edu/bitstream/handle/1/3693423/
Weitzman-OnModeling.pdf7
sequence=2
``Much more unsettling for an application of expected utility
analysis is deep structural uncertainty in the science of
global warming coupled with an economic inability to place a
meaningful upper bound on catastrophic losses, from disastrous
temperature changes. The climate science seems to be saying
that the probability of a system-wide disastrous collapse is
non-negligible even while this tiny probability is not known
---------------------------------------------------------------------------
precisely and necessarily involves subjective judgments.''
When a comprehensive decision analysis includes plausible
catastrophes with unknown probabilities, the policy implications can be
radically different from those suggested by optimal decision making
strategies targeted at the most likely scenario. Weitzmann argues that
it is plausible that climate change policy stands or falls to a large
extent on the issue of how the high impact low probability catastrophes
are conceptualized and modeled. Whereas ``alarmism'' focuses unduly on
the possible (or even impossible) worst-case scenario, robust policies
consider unlikely but not impossible scenarios without letting them
completely dominate the decision.
In summary, the IPCC focus on providing information to support the
establishment of an optimal CO2 stabilization target doesn't
address two important issues for driving policy:
reducing vulnerability to extreme events such as
floods, droughts, and hurricanes
examination of the plausible worst case scenario.
There are no ``silver bullet'' solutions
Xu, Crittenden et al.\14\ argue that ``gigaton problems require
gigaton solutions.'' The wickedness of the climate problem precludes a
gigaton solution (either technological or political). Attempts to
address the climate change problem through a U.N. treaty for almost two
decades have arguably not been successful. The climate change problem
now walks hand-in-hand with the ocean acidification problem, the link
between the two problems being the proposed stabilization of
atmospheric CO2. The proposed solution to the wicked climate
problem and ocean acidification in terms of stabilization of
atmospheric CO2 has revealed and created new problems in
terms of energy policy. Energy policy is driven by a complicated mix of
economics and economic development, energy security, environmental
quality and health issues, resource availability (e.g. peak oil), etc.
---------------------------------------------------------------------------
\14\ http://www.spp.gatech.edu/faculty/marilynbrown/sites/default/
files/attachment/Gigaton%20Problems %20Need%20Gigaton%20Solutions.pdf
---------------------------------------------------------------------------
Even if climate change is not the primary driver in energy policy,
the climate-energy nexus is a very important one. Not just in the sense
of anthropogenic climate change motivating energy policy, but weather
and climate are key drivers in energy demand and even supply. On the
demand side, we have the obvious impact of heating and cooling degree
days. On the supply side, we have oil and gas supply disruptions (e.g.
hurricanes in the Gulf of Mexico) plus the dependence of hydro, solar,
and wind power on weather and climate. What is perhaps the most
important connection, and one often overlooked, is the energy-water
nexus, whereby power plants requiring water for cooling compete with
domestic, agricultural, industrial, and ecosystems for the available
water supply.
The complexity of both the climate and energy problems and their
nexus precludes the gigaton ``silver bullet'' solution to these
challenges. Attempting to use carbon dioxide as a control knob to
regulate climate in the face of large natural climate variability and
the inevitable weather hazards is most likely futile. In any event,
according to climate model projections reported in the IPCC AR4,
reducing atmospheric CO2 will not influence the trajectory
of CO2 induced warming until after 2050. The attempt to
frame a ``silver bullet'' solution by the UNFCCC seems unlikely to
succeed, given the size and the wickedness of the problem. The wicked
gigaton climate problem will arguably require thousands of megaton
solutions and millions of kiloton solutions.
Moving forward
Climate scientists have made a forceful argument for a looming
future threat from anthropogenic climate change. Based upon the
background knowledge that we have, the threat does not seem to be an
existential one on the time scale of the 21st century, even in its most
alarming incarnation. It is now up to the political process
(international, national, and local) to decide how to contend with the
climate problem. It seems more important that robust responses be
formulated than to respond urgently with a policy that may fail to
address the problem and whose unintended consequences have not been
adequately explored.
The role for climate science and climate scientists in this process
is complex. In the past 20 years, dominated by the IPCC/UNFCCC
paradigm, scientists have become entangled in an acrimonious scientific
and political debate, where the issues in each have become confounded.
This has generated much polarization in the scientific community and
has resulted in political attacks on scientists on both sides of the
debate, and a scientist's ``side'' is often defined by factors that are
exogenous to the actual scientific debate. Debates over relatively
arcane aspects of the scientific argument have become a substitute for
what should be a real debate about politics and values.
Continuing to refine the arguments put forward by the IPCC that
focus on global climate model simulations projections of future climate
change may have reached the point of diminishing returns for both the
science and policy deliberations. Further, the credibility of the IPCC
has been tarnished by the events of the past year. It is important to
broaden the scope of global climate change research beyond its focus on
anthropogenic greenhouse warming to develop a better understanding of
natural climate variability and the impact of land use changes and to
further explore the uncertainty of the coupled climate models and the
capability of these models to predict emergent events such as
catastrophic climate change. And far more attention needs to be given
to establishing robust and transparent climate data records (both
historical and paleoclimate proxies).
Regional planners and resource managers need high-resolution
regional climate projections to support local climate adaptation plans
and plans for climate compatible development. This need is unlikely to
be met (at least in the short term) by the global climate models. In
any event, anthropogenic climate change on timescales of decades is
arguably less important in driving vulnerability in most regions than
increasing population, land use practices, and ecosystem degradation.
Regions that find solutions to current problems of climate variability
and extreme weather events and address challenges associated with an
increasing population will be better prepared to cope with any
additional stresses from climate change.
Hoping to rely on information from climate models about projected
regional climate change to guide adaptation response diverts attention
from using weather and climate information in adaptive water resource
management and agriculture on seasonal and subseasonal time scales.
Optimizing water resource management and crop selection and timing
based upon useful probabilistic subseasonal and seasonal climate
forecasts has the potential to reduce vulnerability substantially in
many regions. This is particularly the case in the developing world
where much of the agriculture is rain fed (i.e. no irrigation). It
would seem that increasing scientific focus on seasonal and subseasonal
forecasts could produce substantial societal benefits for tactical
adaptation practices.
The global climate modeling effort directed at the IPCC/UNFCCC
paradigm has arguably reached the point of diminishing returns in terms
of supporting decision making for the U.N. treaty and related national
policies. At this point, it seems more important to explore the
uncertainties associated with future climate change rather than to
attempt to reduce the uncertainties in a consensus-based approach. It
is time for climate scientists to change their view of uncertainty: it
is not just something that is merely to be framed and communicated to
policy makers, all the while keeping in mind that doubt is a political
weapon in the decision making process. Characterizing, understanding,
and exploring uncertainty is at the heart of the scientific process.
And finally, the characterization of uncertainty is critical
information for robust policy decisions.
Engagement of climate researchers with regional planners,
economists, military/intelligence organizations, development banks,
energy companies, and governments in the developing world to develop a
mutual understanding about what kind of information is needed can
promote more fruitful decision outcomes, and define new scientific
challenges to be addressed by research. The need for climate
researchers to engage with social scientists and engineers has never
been more important. Further, there is an increasing need for social
scientists and philosophers of science to scrutinize and analyze our
field to prevent dysfunction at the science-policy interface.
And finally, climate scientists and the institutions that support
them need to acknowledge and engage with ever-growing groups of citizen
scientists, auditors, and extended peer communities that have become
increasingly well organized by the blogosphere. The more sophisticated
of these groups are challenging our conventional notions of expertise
and are bringing much needed scrutiny particularly into issues
surrounding historical and paleoclimate data records. These groups
reflect a growing public interest in climate science and a growing
concern about possible impacts of climate change and climate change
policies. The acrimony that has developed between some climate
scientists and blogospheric skeptics was amply evident in the sorry
mess that is known as Climategate. Climategate illuminated the
fundamental need for improved and transparent historical and
paleoclimate data sets and improved information systems so that these
data are easily accessed and interpreted.
Blogospheric communities can potentially be important in
identifying and securing the common interest at these disparate scales
in the solution space of the energy, climate and ocean acidification
problems. A diversity of views on interpreting the scientific evidence
and a broad range of ideas on how to address these challenges doesn't
hinder the implementation of diverse megaton and kiloton solutions at
local and regional scales. Securing the common interest on local and
regional scales provides a basis for the successful implementation of
climate adaptation strategies. Successes on the local and regional
scale and then national scales make it much more likely that global
issues can be confronted in an effective way.
Biography for Judith A. Curry
Dr. Judith Curry is Professor and Chair of the School of Earth and
Atmospheric Sciences at the Georgia Institute of Technology and
President of Climate Forecast Applications Network (CFAN). Dr. Curry
received a Ph.D. in atmospheric science from the University of Chicago
in 1982. Prior to joining the faculty at Georgia Tech, she has held
faculty positions at the University of Colorado, Penn State University
and Purdue University. Dr. Curry's research interests span a variety of
topics in climate; current interests include air/sea interactions,
climate feedback processes associated with clouds and sea ice, and the
climate dynamics of hurricanes. She is a prominent public spokesperson
on issues associated with the integrity of climate science, and has
recently launched the weblog Climate Etc. Dr. Curry currently serves on
the NASA Advisory Council Earth Science Subcommittee and has recently
served on the National Academies Climate Research Committee and the
Space Studies Board, and the NOAA Climate Working Group. Dr. Curry is a
Fellow of the American Meteorological Society, the American Association
for the Advancement of Science, and the American Geophysical Union.
Discussion
Chairman Baird. Thank you, Dr. Curry.
I apologize. Our AV unit, which none of you, apparently,
requires, is deciding to cool itself off, perhaps
metaphorically. It may be smarter than we think.
Thank you all for your testimony.
The structure of today's hearing, as I mentioned from the
outset, was to talk first about the basic science. Are we
seeing impacts and then what are the impacts? What is happening
and how does it impact our lives? We have got outstanding
witnesses, and what I would like to do is follow up with each
of you sort of on individual themes, but then, if there are
crosscurrents to that, please address those.
The U.S. Navy and Weather Conditions
Admiral Titley, I have had the privilege when I have been
to Afghanistan, Iraq, and other theaters, you know, there are
command daily briefings. And the idea is that a regional
commander gets to look at all sorts of things: What's our force
strength, what's our availability mobility, et cetera, et
cetera.
One of the key elements of that is always weather. You
know, are there going to be dust storms? Are there going to be
clouds? Can the drones see what their targets are? Will we have
air cover? Et cetera.
It must be especially acute in the Navy for your mission,
and what occurs to me is you would be irresponsible as a
commander if you did not take into account weather changes. The
things you have talked to us today about, including the
infrastructure commands, the changing potential in sea lanes,
available access to ports, et cetera, that's a longer-term
frame. But would you not be equally irresponsible if you didn't
look ahead to that and try to make long-term strategic plans,
not just tactics but strategy on the ground?
Elaborate on how the Navy views this issue.
Admiral Titley. Yes, sir. I am not sure I can say it much
better than what you did, but at the risk of going downhill
from here, I will try.
You are absolutely right, sir. I have done weather
forecasting in the Navy now for over 30 years. It starts off
sort of at the unit level or the tactical level. We look at
both the safety of the forces--really, you know, the Navy has
learned that really from time immemorial going to sea.
But certainly, in the typhoon of 1944, Admiral Halsey
tragically lost three destroyers and over 700 sailors because
we didn't know there was a typhoon out there. We fixed that. We
have a Joint Typhoon Warning Center staffed by the Navy and the
Air Force, and we have not had a repeat of that situation,
thank God, since then.
As you get more senior, you start looking at operational
level. What will be weather and the ocean be in three, four, or
five days? Where do I put my units to best have my chance of
success?
I think Heidi Cullen mentioned that climate is putting the
odds in your favor, and that's how I look at the weather. I
talk about the weather as we all operate in nature's casino,
and I intend to count the cards. The bad news is there is a lot
more than 52 cards. The good news, if you can do it, nobody
breaks your kneecaps. So that is really what we are trying to
do, is to put the odds in our favor.
And now, sir, as you absolutely have it spot on, we are
looking strategically out. So not just three, four, or five
days, but what are the next 20, 30, 50 years going to look
like?
We can see the signal in the Arctic. The observations tell
us what's going on. We see that the percentage of what's called
multiyear, the thick ice has dropped to levels that, frankly,
we have not recorded before. So although 2007 was in area
extent the least amount of sea ice that was recorded, in '08,
'09, and '10 the levels were slightly higher, when you look at
the volume of ice, the volume as of last September has never
been lower.
And in respect to Congressman Rohrabacher, I should not say
never. In the last several thousand years, it has not been
lower.
So we see the probable, probable opening of the Arctic. I
have told Admiral Gary Roughead, our Chief of Naval Operations,
that we expect to see about four weeks of basically ice-free
conditions in the Arctic in the mid to late 2030s. By the
middle of the century, we could be seeing quite easily two to
three months of ice-free conditions. That's enough time to
allow the trans-ocean shippers, assuming they have governance,
search and rescue, charting, insurance, all of those other
conditions, but by the middle of the century that's very, very
possible.
When I talk to my colleagues in Iceland, Iceland is
actively thinking about how do they become the Singapore of the
21st century? How do they become that southern terminus? This
becomes a very different ocean and a very different world for
our Navy to operate in.
So this is just one example. I could talk about sea level.
I could talk about ocean acidification. In the interests of
time, sir, I will stop here.
But you are exactly right. This is looking at what we
believe, not guaranteed, but is likely to happen and looking at
consequences, times probabilities, and planning for those kinds
of situations. And that's what we have embarked on, sir.
Chairman Baird. That's a very, very helpful summary.
Climate Monitoring Instrumentation
A context of that also is that not with infrequency people
here on the Committee will hear a suggestion that all the money
that has been spent on climate change research has been wasted.
Well, a fair bit of the instrumentation that has been used to
gather the data that leads to the analysis came from Defense
applications, whether it's satellites in the air, whether it's
sensors on equipment. And certainly my hunch would be that down
the road you folks will be mighty glad to have those sensors
and the data that they have given you as you make your
planning.
Admiral Titley. Yes, sir. The data are very useful.
We use data from a wide variety of sources. I am sure you
know, sir, that the submarine missions that we had run not only
in the Cold War but in the 1990s, they provide very, very
valuable ground truth observations of how thick is that ice so
we can then calibrate or basically tune our satellites.
I would be remiss, though, sir, in saying this does not
also work in the other direction. The Department of Defense is
a big user of the civil structure that in part is appropriated
from your committee. We work very closely with NOAA. I have a
great relationship with Dr. Lubchenco.
And one of the things, sort of on the practical adaptation
side we are jointly looking at between the Navy and NOAA and
the Air Force, also have Department of Energy and NASA
involved, is how do we look at a next generation of weather,
ocean, ice coupled prediction models so that by roughly 2020,
in about ten years from now, we can predict that system as a
whole and really going--spanning between weather time frames,
say hours to days, out to say roughly about two or three
decades.
Because as we are planning for our infrastructure--or let's
say if you are the port of New York and New Jersey, you are
planning for your infrastructure. You want to be looking at
that. There are--for very, very good reasons there are
boundaries in the science community between the weather folks,
the oceanographers, the glaciologists, the climatologists. But
if you are a decision-maker, if you are running a business, if
you are running a government agency, you know, with all due
respect, you don't really care what those boundaries are. You
need an answer, and your answers span these time frames.
I wish I had thought of putting it this way, but the words
of Rick Anthes, a former Director of the National Center for
Atmospheric Research, he said, hey, Titley, what you are trying
to do is go between a condition forced by initial conditions,
you know, what is today's weather, to one forced by boundary
conditions. What is the Sun doing? What are the greenhouse
gases doing? How do we get through there? Open science
questions.
Big challenge. But I think it's a great challenge for this
Nation of ours and one that will help us as we adapt in a cost-
constrained environment.
Thank you, sir.
Chairman Baird. Thank you. Thank you, very much.
Adaptation Challenges and Poor Communities
Mr. Lopez, I am intrigued by this issue of mitigation and
adaptation, particularly as things apply to perhaps
disadvantaged communities. And it seems there are two--well,
there are multiple factors, but one is not only domestically in
the United States but globally a lot of the folks who are going
to get--if there are the impacts which are projected, which
seems more probable than not, in many cases, anyway, if those
impacts happen, they are going to impact some of the people who
had the least to do with causing the problem and the fewest
resources to cope with the problem. Can you elaborate on that
domestically within our own sociodemographic span but also if
you have insights into it globally how that impacts the world?
Mr. Lopez. I think that's absolutely correct. I think
that's of particular concern for us at HUD.
As we implement our programs and policies, we want to make
sure that the populations that we serve, we are thinking
through adequately about the future stresses that might be
imposed on those populations, knowing that the more stresses
you have today the more likely you are impacted to be tomorrow.
And I think there is a couple of points of insight, focusing
more on the domestic side of things, that I would like to make.
And, first, as the Admiral points out, you know, these
decisions, they are being made today. It's not like we can
wait. Moving beyond the military example, the hundred-year
flood plan, the management of goods and services, agricultural
economic development, the built infrastructure, which is what
we deal with at HUD, we have to make decisions now about the
future. And those decisions can't wait. So our challenge is how
do you take that fact and build a system or a process that
helps to mainstream or integrate the climate change variable?
And I would suggest a couple of things.
One, and I think it's endemic to these grants we put out,
is to find the triggers. There are those communities that are
aware of the assumptions of climate change, but there are
opportunities that happen, planning opportunities like the
challenge grants and the Regional Planning Grants that we have
put out. Disaster recovery is an opportunity where you open up
and start to say, okay, what does the future look like when we
have to rebuild? Infrastructure investments. When you have to
spend a billion dollars on a wastewater treatment facility you
want to make the best decision you can. And it's really about
learning as much as you can right now about what you need to
know about the future.
So I really think, Mr. Chairman, it comes down to better
decisions. And for us it's the populations in large measure
that you identified. So it's about scenario planning, and it's
really about how do you help communities make a decision most
compatible with uncertainty?
We know there is uncertainty. Local governments and
governments at all levels make decisions with uncertainty every
day. It's about making the assumptions about climate in those
decisions transparent, understanding them better, and making
decisions in uncertainty.
And one guiding lesson we learned, in my perspective coming
from local government to the Federal Government, is to think on
the margin. It's about the marginal cost of what you need do
next. It's not necessarily about building a whole new system.
It's about the marginal cost of building the reclaimed water
system to the billion dollar investment you already made. And
when you reach that point you can do a cost-benefit analysis
based on the margins to see how much you know, how much you
understand about the future, and whether or not the investment
is worth it.
And the final point I would make is you always have to
consider the co-benefits. For us, we are acutely aware of where
you build, how you build, how you help communities prepare for
the future. That's what we do. Green roofs, green space, energy
efficiency, water. It's reuse. It's conservation. All of these
things are co-benefits to decisions that have to be weighed in
I think when you are analyzing the marginal cost of the
decision.
Chairman Baird. Very well put.
I had the privilege of riding on a cross-country flight
with Secretary Sims, who I have great respect for and served
our region very well. You mentioned the co-benefits. One of the
things that I was so impressed with was the Secretary's
analysis of things like health benefits from healthier
communities. If we do if right, there is a positive synergy to
this. If we preserve green space, that, if properly planted,
can take up CO2. If we change how roofs are colored,
that can produce greater reflectance, et cetera, and reduce
temperatures inside homes, et cetera.
One of the things I would hope we don't do as a body is
those who are antagonistic to the climate change scenario, that
they don't say anything that was ever done in the name of
climate science we are going to reverse, sort of analogous to
taking the photovoltaic panels off the White House as a
statement. Well, if we do that, we are going to roll back a lot
of things that have co-benefits in and of themselves, and I
think that would be really unfortunate for all of the interests
we have heard today.
Briefly, I will particularly direct this to Rear Admiral
Titley and Mr. Lopez, but if others want to comment as well,
and then I will get back to specific questions.
A National Climate Service
We in this committee have had significant discussion over
whether or not a climate service is needed. If so, what would
its benefits be? From Admiral Titley and then Mr. Lopez and
then Mr. Geer and Dr. Curry, what are your thoughts about with
whether or not a climate service would be useful to you? And
what would be useful about it if it existed?
Admiral Titley. Sir, thanks very much for the question.
A climate service, I believe, would be very useful for the
Navy. It provides--I almost hate the phrase--but a one-stop
shop, if you will, or at least a source of both coherent and
authoritative data. It would be ideally staffed by people who
would be conversant with those data, as well as, of course,
machine to machine ways of pulling these.
We have lots of different places with very good quality
that produce various types of climate models. The National
Centers for Atmospheric Research, the Department of Energy have
some tremendous programs, as do academia, et cetera. As a DOD,
I do not want to replicate or duplicate. We cannot spend our
taxpayers' dollars doing things that have already been done
well, but I need access to that.
Chairman Baird. But you need that data.
Admiral Titley. But I need access, and I need to be able to
get it without sort of the hunt and peck method, or whatever we
call Google now on the hunted. Back when you and I were growing
up, it would be the hunt and peck method.
So having that, you know, probably in one agency. I know
NOAA has looked at this. And, you know, that would make sense
to us. So whatever the Committee and the Congress and the
administration ultimately decide, the concept of a climate
services would be very, very useful.
Chairman Baird. The model of that would be that it would
interface with a number of other areas like Agriculture,
conceivably Fish and Wildlife, conceivably HUD, obviously, the
Defense applications. That's the model that we had in mind. And
you know, it's not a one-way street. It's not that the climate
service tells you what's happening. Ideally, the climate
service gathers information from your resources and expertise
and data sets, and it's a synergistic model.
Mr. Lopez or any others want to comment on that issue? Mr.
Geer?
Mr. Geer. Yes. From the Fish and Wildlife perspective, we
support heavily the establishment of a national climate
service. We feel that as additional information becomes
available on a scientific basis we need to have that
information to make intelligent management prescriptions on
specific places around the country geographically. What's
pertinent in the intermountain west, which is a relatively arid
environment in a changing climate, may still be different than
what it is in the Southeastern U.S. And what we need is
geographically specific information, the best prediction we can
get.
So the strategies that we put on the ground are the ones
that are pertinent and applicable for that particular area so
we don't waste the money either for them to be effective. We
need a information central kind of area where we can store the
information, we can retrieve the information, we can find out
where it comes from, we consult with others, we have a much
better information base, we are better informed as
professionals, and we can do a more effective job.
We think that such a climate service ought to be
coordinated among the state and federal agencies so everyone
can--this is a worldwide issue. We can all participate in the
data gathering and the data sharing and the interpretation.
Chairman Baird. Dr. Curry and then Mr. Lopez.
Dr. Curry. With regards to climate service, I think the
fundamental need is really the information system. For example,
the sea ice issue that was raised earlier, which of the 12 sea
ice data sets that are out there should we be looking at? I
mean, there is a bunch of different data sets. The average user
doesn't know which one to use. There is no error assessments.
And then they look at it and they see sea ice in Mediterranean
and how are they supposed to interpret that? I mean, these data
sets are not--
Chairman Baird. There is no sea ice in the Mediterranean.
Dr. Curry. I know, but some data sets give it to you there.
Chairman Baird. Is that true?
Dr. Curry. Oh, yeah.
Chairman Baird. That's obviously not a data set.
Dr. Curry. Certain satellite products, if there is clouds,
they will mistake clouds for sea ice.
Chairman Baird. Got you. Okay.
Dr. Curry. And you can get sea ice in the Mediterranean. So
how useful are those kind of data sets?
Chairman Baird. Could we ski in it?
Dr. Curry. My point is we need to establish authoritative
climate data records, where people sift through the
information, look at the uncertainties, and give somebody one
data set that they can use.
Chairman Baird. With some error boundaries.
Dr. Curry. With some error bounds on it.
And, also, it's an issue of accessibility. People need to
be able to search and use the data sets. And, otherwise, trying
to--even for somebody like me, sometimes trying to get the
climate data I need, it's like--it's torture----
Chairman Baird. Yeah.
Dr. Curry. Okay--compared to somebody who is not even a
climate researcher, who is just trying to use the data set. We
have a very fundamental need for a climate data information
system.
Chairman Baird. So some kind of combination of open source
but with a qualitative filter to it.
Dr. Curry. Open source would be an interesting route to go.
Chairman Baird. Mr. Lopez?
Mr. Lopez. Thank you, Mr. Chairman.
I think I would like to stay within the confines of the
task force report, part of our charge, and what we were calling
is a National Climate Change Adaptation Strategy. And I think a
lot of the principles that we have discussed--the need to get
information out, the need for a dialogue with the scientific
community, a process by which we can evaluate that information
and embed it into our mission of each agency and across the
Federal Government and down to the states and local
governments--is part of that process. And I think moving
forward we hope to continue a dialogue with you as we work on
that.
Chairman Baird. Okay. Thank you.
The Impacts of Climate Change on Recreational Fishing
Mr. Geer, I want to ask you specifically, I represent an
area where hunting and fishing is huge. The southwest
Washington people love to hunt. I grew up as a hunter. We
literally fed our family by hunting and fishing. That was our
main source of protein, was venison or elk or antelope or
rabbit or duck, whatever. If it moved, we shot it. If we shot
it, we ate it. And we ate all of it. And that's the case in a
lot of my district.
And, in addition, the recreational pursuit is tremendously
important to people. I had the opportunity to talk to--one of
the ongoing fights back home is gill nets versus sports
fishermen. I had a long conversation with a bunch of sports
fishermen concerned about gill netting, and I think it's a
legitimate and important debate. But, at the end of it, we
began to talk about ocean acidification; and these folks really
hadn't heard much about it. And it struck me that, you know, we
are focusing so much on one issue sometimes.
What impact do you see--if we have ocean acidification, as
you heard Dick Feely testify to earlier, and you lose
pteropods, you lose the basic food chain for salmonids, and if
you increase the temperature of the water--back home, we go
nuts, appropriately so, providing shade, et cetera, for streams
and other tributaries so that the salmon can spawn in cool
water. What do you see is the combination with more acidic
water and higher temperature water on just, say, for example,
salmonids to take one example?
Mr. Geer. Well, I think it's a fairly simple prediction in
some regards. If you have less food, you have a smaller
population base perhaps of less healthy fish who are able to go
upstream and spawn. Then you have an environment upstream
that's not particularly inviting for them in the first place.
There are some questions to be asked on whether or not, for
example, will the chemical makeup of the water at that time
change to the point they do not recognize their homing stream
anymore, which will upset their spawning behavior? And if they
do find the correct stream, or a stream, will they have a
physical environment that still enables them not only to
spawn--it's not just the act of spawning, the act of
recruitment is you also have to have egg hatch.
One of the things, if you have worked in fish hatcheries,
we deal with things called degree days. A degree day is one
Centigrade for one day. And, typically, an egg for a salmonid
is going to require a little over 300 degree days to hatch. And
if you have a species that's spawning in spring and is tied to
the flow, you have fewer days with warming water than a species
that spawns in the fall and has cold water for a longer time.
But those cycles are timed to not only when the eggs hatch
but what physical environment for the young-of-the-year fish
exists at that time. Is there side water for younger-than-year
fish, which are not muscular, they are small, they are prone to
being washed away and to be preyed upon by big fish. Are there
areas of flow at the time of year that they can escape to so
you have successful recruitment, spawning, hatching, and
survival of young fish to the next age class so they can go
downstream?
So it's a whole series of factors. But if you start with
the fact that you have fewer fish to move upstream because you
have a smaller body of fish in the ocean and they are of poorer
health, they have physiologically a less suitable condition,
you have a smaller population going up, you have a reduced
spawn size, perhaps a less favorable environment, a lower
recruitment, and you have a decline of salmonid populations.
You are talking steelhead and Pacific salmon.
Adaptation of Animal Species to a Changing Climate
Chairman Baird. What you have hit upon seems so important
to me. Because when we talk about this issue sometimes people
say to themselves--I hear it a lot--wait a second, you are
talking one degree, two degrees. My understanding of the
biology of many species is that many of them live fairly near
the upper bounds of their temperature tolerance. And a one
degree change in water temperature over a period of time can be
lethal. A change in pH level can be lethal. Integrated, they
can have a terribly negative synergy. And now you are adding in
all the of the other variables about stream flow, other habitat
issues, nutrition supplies, et cetera. Even small changes can
produce those impacts?
Mr. Geer. Depending on where they are on the tolerance
curve. If you have something, for example, like rainbow trout,
that, if you are looking Fahrenheit, that have an optimal
temperature of 55 degrees Fahrenheit, you have some wiggle room
on either side where you can still have either good growth or
slower growth and a viable population. But when you get up five
degrees or something, you are getting to smallmouth bass range.
Suddenly, you have physiologically less adaptable fish, you
have lower reproductive success, and you have the opportunity
for what we are calling invasive species, species that don't
normally belong there intruding on their territory, which is
what's happening in the Yellowstone River, the Clark Fork
River, the Bitterroot River, and some other areas. You have
species that are more competitive, that operate in a higher
temperature range. When you get on the upper edge of their
thermal tolerance, that's when you get the higher level of
risk.
One of the things I have noted over the years as sort of a
general observation, though, that as humans we tend to think as
the center of the universe, and we tend to think that what we
understand is really what's important. We confuse lack of
understanding with lack of importance. We don't understand how
a small temperature difference can make a large difference to
something else where it may not to us.
We are in an insulated environment. We are in a comfortable
room, thermostat controlled, comfortable. Well, if you are
outside living in the environment without a thermostat, things
are a little bit different, and they don't respond to the same
stimuli that we respond to.
And one of the things that we work on in animals, we can
debate, for example, whether or not the science is exactly
right, whether or not they are at the upper ends of the thermal
tolerance or whatever. We can debate the policy outcomes that
come out of this and even the range of the economy. But the
animals don't get that vote.
Chairman Baird. They don't get to turn the thermostat up.
Mr. Geer. They go where the environment is within their
life history and their tolerance. If their habitat's not here,
if they are mobile enough, they will go to where it is. And
some of them will not enjoy that advantage. They are already at
the limits of their tolerance, and there is nowhere else to go.
If you are a mountain goat, where do you go? You are already at
the high end. So they go to where the habitat suits them. If it
no longer suits them, then we have a decline in the species.
Chairman Baird. And they don't have time to evolve to adapt
at the pace of change.
Mr. Geer. No, at the pace that we are changing things right
now, we are talking evolutionary changes, maybe a hundred years
or perhaps thousands of years. But we are talking things that
are going to change much more rapidly, and they simply haven't
got time to physiologically adapt in many cases to the
environment that we predict may occur. And I hope that we are
all wrong, actually, and that we have overestimated that. But
the odds aren't looking good.
Chairman Baird. Yeah.
Combined Factors Affecting Climate
Dr. Curry, I was intrigued by one of your observations I
thought was very telling and I think important. It's not just
CO2. There are other factors. I caught at least two
of them, population and land use. Those are also integrated,
however, with CO2 output. Can you elaborate? I mean,
there is--they combine to have combined effects. Can you
elaborate on that somewhat?
Dr. Curry. Well, our vulnerability to global warming is
largely associated with ever-increasing population, where we
choose to build and what we do to our ecosystems and how we
engineer our, you know, we get rid of some of our barriers. At
the same time, as population increases this is, you know, a big
part of the carbon dioxide problem. So it's a big, complex,
wicked problem that's coupled in very complicated ways.
And, again, I tried to make the point that there is no
silver bullet solution. And there is all these intersecting
problems. I mean, the climate problem doesn't stand alone. It's
coupled to population, it's coupled to energy, increasingly to
ocean acidification. And we need to look at the broad solution
space, possible solution space for all these issues and try to
figure out what makes sense.
Chairman Baird. This population issue seems so important to
me. Because if each individual has their own personal carbon
footprint, if you will, the popular term, but basically what it
takes for you to live your lifestyle, add a lot more people
wanting a more carbon-intensive lifestyle, you just magnify the
impact.
Dr. Curry. Okay. And the population--where the population
is growing is in central and south Asia. That's where the
rapid, rapid, rapid population is growing. This is where
economic development is huge. And what's going on there is
going to totally dominate--well, it's already dominating the
CO2 story, and it's going to explode really in terms
of dominating the carbon dioxide situation. And so that becomes
a whole political issue about, you know, what India and China
does and how we deal with risks.
And the whole issue of who is a winner and loser, again,
north China looks a lot more favorable in a warmer climate
potentially, okay, with more water and a nicer climate, you
know, during part of the year. And so what is going to be their
motivation?
You know, we haven't really looked at, you know, the
winners and losers part of this story in the way that we should
and really understood vulnerabilities. I mean, in the United
States we have a fairly good of it. But in a lot of the
developing world that are either very vulnerable, or like India
and China, South Asia, that are going to be the big powerhouses
in terms of emissions and populations, we just really haven't
done a lot of the analysis that we need to do to really sort
this out.
Chairman Baird. What about the argument that, well, you
know, there are so many Chinese, so many people in India and
Indonesia, et cetera, they are going to pump out so much
CO2 that what we do here doesn't matter?
Dr. Curry. Well, superficially, it doesn't, but the Chinese
have already poisoned their environment in pretty serious ways.
So their big motivation for doing something about it is really
trying to stop the poisoning of their soil, water, and air.
Okay. So that's their motivation.
And on one hand it doesn't. But everybody's going to need--
there is no way that the developing world is going to be able
to compete for, like, petroleum, you know, in terms of dollars,
especially when we see peak oil or whatever. So there is going
to have to be alternative energy sources of some sort. And the
people who take the leadership in that area is going to be less
vulnerable to price swings and global security issues and
whatever. So there is a lot of motivation for being out there
in front and taking a leadership position on all these
alternative energy strategies.
Blogging, Scientific Integrity, and Public Information
Chairman Baird. One final question for you, and then we
will bring it to a close, I suppose.
I had the opportunity in almost every case here to look
online at other things that you had done. And you mentioned the
blogosphere. I will tell you I was pretty troubled by--I went
on a few climate sites on both sides, and it was not the
scientific dialogue that I am trained in. It was snarky, it was
nonsubstantive, it was ad hominem, it was juvenile, and it was
unconstructive.
Dr. Curry. A lot of it is. Okay. But there is what I would
call the technical climate blogs that have spun up, and these
are people who have an interest in analyzing the data and
looking into the science, and people from both sides of the
debate show up. So some of the more high-profile ones are very
snarky and polarizing. But the blogosphere has sort of
developed this sort of lukewarmer technical blogging community
where people are actually looking at the data, debating
scientific papers, people from both sides in a fairly civilized
way. And so I view this as something that it's important to tap
into and acknowledge this interest, and there is potential for
reducing polarization.
Chairman Baird. Somehow there has got to be. And I
mentioned at the outset--and I know you have written on this. I
mentioned at the outset this issue of science integrity. We
literally wrote it into the America COMPETES bill. Now you
can't get a NSF grant. But you can blog with nothing. It's an
important point. And the reason it's so important and the
reason we are having this hearing is to try to say, look, this
idea of science by ad hominem attack, by politicization, by
false accusations, by conspiratorial theories, by labeling
things hoaxes, that ain't science.
Dr. Curry. I know it's not. But it's going to happen
whether the blogosphere is there or not.
I am just saying by engagement, a lot of it--so many people
distrust climate scientists and climate science. I mean, they
view them as arrogant and whatever, and they were worried about
U.N. policies taking over everything, and they were sort of
scared. And then when Climategate struck with the e-mails, you
know, then people really had more of a concrete reason that
they felt not to trust scientists.
Chairman Baird. Would you say that that, though,
obliterates all the legitimate data----
Dr. Curry. Not at all. But it is an issue of the public
trust, and a lot of the things like the IPCC assessment report
is a heavy dose of expert judgment in those conclusions. And if
you don't trust the experts, you know, what are we to make of
their judgment? So the data and the fundamental research is
there. It is how it is assessed, communicated, and by whom it
becomes an issue.
Chairman Baird. This is helpful.
You know, I thank you all.
An Anecdote on Risk Management
I will share an anecdote that occurs to me. Some years ago,
I was climbing Mount Rainier. We were going up in the
springtime. It was early and these wicked whiteouts happened.
And if you have never been in a whiteout, it is really quite an
experience. You literally have no sense of vertical, up or
down. And we were walking with ski poles in front of us so we
don't walk off. We are literally sort of probing because you
can't see the earth. It is bizarre. And I had had the good
fortune and maybe good sense to actually when we left this hut
at Camp Muir to actually take my compass out and take a compass
reading. And so we follow this compass reading.
Everybody else was just walking the way they think we
should walk, and I had the compass reading. And at some point I
said, I just don't like the feel of this. We haven't come back
across the trail I thought we should have and our intuition
says we should go this way. If we are wrong, I knew from many
climbs previously, there is about a 1,500 foot drop down to the
Nisqually Glacier.
Now, I said, you know, maybe what we ought to do is gather
together and check our instruments. I happened to have an
altimeter with me and a top map. It was mighty handy. So I had
the top map. I had the topographic map, I had the altimeter,
and I had the compass reading from where we had gone.
Everybody else in the party pretty much was saying we are
going to go this way. We are sure it is this way. And I said,
well, here is the point on the map where my instruments tell me
we are. If we walk another 200 meters this way, I think we walk
off a 1,500 foot cliff as many others have done in equal
conditions. The alternative, unfortunately--because we had gone
this way this far--was unpleasant. We had to actually go
uphill. And when you have climbed all day and you have got a
heavy backpack on and it is deep snow and it is spooky and it
is--you don't want to go back uphill. You hate it. It is hard
work. You are tired. It is not what you want. Relative to a
1,500 foot downhill----
Well, we trusted the instruments because I had them, and we
walked back. And I have never been so happy as I have in my
life to see some spilled Gatorade on the snow about a half hour
later. We had to literally change direction and walk uphill.
The instruments gave us the data. And we could have gone where
we wanted to go, where it seemed easy to go, where our
intuition and our experience seemed to suggest it would go, but
the data suggested something otherwise and we followed the
data. And I probably wouldn't be here today because I was on
the lead of the sharp end of the rope.
The point of our hearing today--and I think the point of
this committee I hope, which I am loath and sad to leave--is
that we have an obligation to approach decision making in a
constitutional democratic republic with rationale, empirical
judgment and information, imperfect and uncertain but the best
we can do. And the hope today was we had a model of how that
can happen. We won't reach any conclusions.
I don't think anybody is going to say, well, dang, I was a
complete skeptic before, now it has turned. Maybe some will go
the other way. But the process that we try to follow and the
process of science is what is going to get us there. And I
would hope that that process, that legacy on this committee, if
no other, is one based on empirical decision making, mutual
respect, critical analysis, objective analysis.
I am grateful for the witnesses on all sides that have
helped us put this forward, and I hope for the sake of the two
5-1/2-year-old boys on which I make every fundamental decision
in my life and countless others that are near and dear to you
that we will weigh the consequences of inaction or inaccurate
action against the consequences of acting in responsible,
reasonable, rational ways for the broader good of not only our
society but the globe itself. And the stakes are pretty darn
high, and we have really got to get it right.
I thank all of you for being here today and all of you who
are--the audience for your perseverance and your patience and
your expert input.
Customarily, there will be two weeks allowed for anyone who
wishes to enter additional extraneous comments into the record.
And with that--thanks. And I would like finally to thank
the staff on both the Majority side and Minority side for their
participation in making this hearing in this last session of
Congress so successful.
With that, the hearing stands adjourned.
[Whereupon, at 2:35 p.m., the Subcommittee was adjourned.]
Appendix:
----------
Answers to Post-Hearing Questions
Answers to Post-Hearing Questions
Responses by Dr. Ralph J. Cicerone, President, National Academy of
Sciences
Questions submitted by Chairman Brian Baird
Human actions and climate change
In your testimony you describe the basic energy balance of the
Earth. In that explanation you state that the Earth's calculated
temperature is lower than the measured temperature. You then state
something must be missing in the calculated temperature of the Earth.
Q1. Does this mean that global warming due to anthropogenic effects is
the missing factor and that the increase in Earth's temperature is due
to human activity?
A1. The big gap that I referred to is that the temperature which we
calculate for the surface of the Earth by balancing the incoming energy
from the Sun, with that which is emitted by the Earth, is about 30C
lower than our actual temperature and this is due to the natural
greenhouse effect. It does not include a human impact. The gap
illustrates the fact that the greenhouse effect is a natural force and
that if we calculate the temperature of Earth's surface or the
temperature of Venus's surface without the greenhouse effect, we obtain
answers which are far lower temperatures than are actually measured.
The cause of this discrepancy is that we have ignored the greenhouse
effect of gases in the atmospheres of Earth and Venus and of clouds in
those atmospheres. The reason that we can calculate the correct
temperature for Mars in this simple way is that Mars has such a thin
atmosphere with so little carbon dioxide and water. This evidence for
the existence of a natural greenhouse effect is one indication of why
the human-enhanced greenhouse effect is also capable of changing
Earth's climate.
Q2. It is important to understand what the human contribution to the
greenhouse effect means. Your testimony states that human's direct
influence is small but we must consider all human energy usage (i.e.
nuclear power, the burning of all fossil fuels, the burning of wood,
etc). What sort of human impact does this translate into for the
greenhouse effect and global warming?
A2. I hope that I did not confuse the issue by mentioning the fact that
all of human energy usage today on Earth that is due to all fossil-fuel
burning, coal, petroleum, and natural gas added to all the energy used
from nuclear power plants, hydroelectricity, all renewable sources of
energy together, add up to only about 1/100th, that is one percent, of
the extra energy trapped near the surface of the Earth by the human
enhanced greenhouse effect. I mention this comparison to show how
powerful the greenhouse effect is as leverage over Earth's physical
climate. I also mentioned it because sometimes I encounter people who
when they hear ``fossil-fuel burning'' think that it is the waste heat
from all of that fossil-fuel burning to which we refer as a possible
cause of planetary climate change. Instead, of course, it is the extra
greenhouse effect caused by the growth in atmospheric concentrations of
the byproducts of fossil fuel usage such as carbon dioxide and methane
which represents human leverage over the climate. Just to provide one
more comparison, I note that all of human energy usage today is
approximately 1/9000th of the energy Earth receives from the Sun while
the human-enhanced greenhouse effect is approximately 1/90th of the
solar energy received by the planet.
Questions submitted by Representative Ralph M. Hall
Of the many revealing aspects of the ClimateGate email scandal,
perhaps none are as disappointing as the great lengths at which
scientists worked to block other researchers from gaining access to
scientific data associated with key global warming findings.
Climate scientist Phil Jones exemplified this attitude when he
responded to a fellow researcher's request by saying ``Why should I
make the data available to you, when your aim is to try and find
something wrong with it?''
This behavior is, at its core, unscientific. The National Academy
of Sciences' Guide to Responsible Conduct in Research states that
``When a scientific paper or book is published, other researchers must
have access to the data and research materials needed to support the
conclusions stated in the publication if they are to verify and build
on that research . . . [G]iven the expectation that data will be
accessible, researchers who refuse to share the evidentiary basis
behind their conclusions, or the materials needed to replicate
published experiments, fail to maintain the standards of science.''
As President of the National Academies, you are obviously very
influential in how scientists apply this basic principle of openness
and data sharing. In an interview after ClimateGate, however, you said
some climate scientists ``are now receiving requests that are bordering
on harassment. They're being asked for all the data that went into a
publication, sometimes in addition to all data analyses, all equations,
used in interpretations, detailed descriptions of all statistical
techniques, all computer programs used--even access to any physical
samples. These are fishing expeditions.''
Q1. Please help us reconcile your statement calling these requests
``fishing expeditions'' with the Academies' guidance stating that
researchers who refuse to share materials needed to replicate published
experiments fail to maintain the standards of science.
Q2. Do you think the Federal government should withhold funding from
researchers that refuse to make their data and materials available for
public scrutiny? Should such research be excluded from use in policy
debates and scientific assessments such as those by the National
Academies or IPCC?
A1, 2. I will address this array of questions and observations by
outlining to you some of the things that the National Academy of
Sciences and I have been doing in the last several years. First, we
published in late 2009 a new report authored by a superb committee of
academic scientists, people from corporations and legal experts,
entitled Ensuring the Integrity, Accessibility, and Stewardship of
Research Data in the Digital Age. This ``data integrity'' report dealt
with a very large array of questions about the form, volume, and value
of various kinds of research data. One of the findings was very similar
to the statement which you quoted from the National Academy of
Sciences' Guide to Responsible Conduct and Research, namely, that
``research data, methods, and other information integral to publicly
reported results should be publicly accessible.'' Implementing this
principle would encourage scientific research to proceed more
efficiently and openly, which is a goal that we all share. The report
notes that in many fields of science, especially those which are of
practical importance such as pharmaceutical development, intellectual
property and software and manufacturing, many kinds of medical
research, and environmental issues where there are sometimes competing
forces at work, there are also specific factors which make it difficult
for all data to be provided to all parties at all times. For example,
there are proprietary restrictions on research that has been supported
by industry. Similarly, there are issues of personal privacy in some
kinds of medical and social research. Third, for example in climate
change, there are datasets which are now the property of individual
governments due to a move that began two or three decades ago to
nationalize meteorological services so that the data and the weather
forecasts can be sold to recover the costs of the government in
establishing meteorological stations and meteorological satellites and
models. Each of these limitations is potentially serious and they must
be dealt with in ways which are appropriate for each field.
Our ``data integrity'' 2009 report noted that in some scientific
fields the individuals most knowledgeable in that particular field of
research have created uniform standards to be employed by researchers
in each specific field and in the journals where they publish. The
report provides examples from a number of fields including space
research, crystallography, and in molecular biology and genetic
databases. In some cases, these field-by-field standards are
promulgated and enforced through research journals, in other cases by
Federal funding agencies, and in still further cases, by leading
scientists in the field who have created a supportive culture for those
standards. In several examples, Federal agencies have provided funds to
create and maintain data repositories which accept data from scientists
who are publishing results and the data repositories provide
professional and permanent archiving of data. The National Academy of
Sciences-National Research Council data integrity report of 2009 also
noted that in the digital age, forms of data are becoming more varied
and numerous, and data storage now involves the maintenance of
supporting data (metadata) required to interpret the data such as
statistical techniques, computer programs to maintain metadata or
housekeeping data, for example, on the position of an Earth-orbiting
satellite or other features of the research protocol that went into
obtaining the data in the first place.
I also note that it was in 2007 when the NAS and the NRC decided to
launch the study that led to our 2009 data-integrity report. The study
was funded by ourselves, several journals and scientific societies and
private foundations, with about one third of the funding from Federal
agencies.
In the last couple of years I have focused my own efforts on how to
create the most uniform set of standards we can in the field of climate
science. For example, in February 2010, I made a special trip to the
annual meeting of the American Association for the Advancement of
Science in San Diego, to propose the need for such standards and to
stimulate discussion among scientists from different disciplines. I
also spoke at public meetings in San Diego on how and why these
standards must be achieved. Just before that San Diego meeting, I wrote
the enclosed editorial for SCIENCE magazine where I addressed these
issues.
In my 2010 annual address to the members of the National Academy of
Sciences, I focused on the issue of the need for standards for data
access across fields of science, again in our desire to advance science
and also to be as responsible as possible to members of the public, to
people with commercial and proprietary interests as well as to protect
scientists from potential harassment. Also early in 2010, I met with
the editors-in-chief of three of the world's major scientific journals
to describe these issues to the journal editors and to learn what they
were already doing to help to promulgate and maintain standards for
access to data on which research publications are based. Following that
meeting, I wrote to and telephoned the elected officers of two strong
American scientific societies who publish important climate research
papers, namely, the American Geophysical Union and the American
Meteorological Society.
In these meetings and contacts, it has become clear that climate
science is an especially challenging field for which to create
standards of data access because the field is comprised of many
subfields such as remote sensing by Earth-orbiting satellites, by
observations of the Sun, by observations of oceanography, of
meteorology both on continents and ocean, and by observations from
paleo objects such as fossilized biological specimens at the bottoms of
lakes, oceans, and soil. The field of climate also includes
mathematical modeling of Earth's climate which in turn generates
enormous datasets, certainly of the order of a few terabytes per
computer run. The field also includes records from sea-level changes
from glaciology and isotopic data from biological and physical
specimens worldwide. Accordingly, climate research is published in
many, many different journals, some of which are owned by the private
sector and are commercial enterprises, other journals of which are
published by scientific societies which are nonprofit. And the rules
governing these publications vary.
In the fall of 2010, I have arranged for more meetings between
myself and officials of the AGU and the AMS to continue to pursue these
questions, and I have begun to reach out to individual leading
scientists to ask them to identify best practices in their field and
the potentials for creating more uniform standards for data access
along with learning from them the pitfalls of trying to implement what
might be seen as simple solutions of a one-size-fits-all nature but
which would be counterproductive and extremely difficult to implement.
I mentioned earlier that there are some kinds of requests for data,
which appear to be harassing because the authors and the scientific
researchers in question have provided reasonable amounts of data to
requestors but have not been able to give away access to individual
physical samples when, for example, the conditions under which the
samples were obtained mitigates against the free distribution of the
samples (as does their scarcity) and expense of distributing the
samples intervenes.
Some of our Federal agencies that conduct research and sponsor
research extramurally, have already put in place standards and data
repositories which are enabling some climate data to be archived,
maintained, and made available in ways which are exemplary. For
example, two of the leading providers of global temperature records,
NASA and NOAA in the United States, have documented very well in a
public way the sources of all of their data, the numbers involved, and
any mathematical operations that they have applied to the data,
including data which have been omitted or otherwise altered before
being used in the dataset. These records are easily available through
NASA and NOAA websites, and I think they have encouraged research by
other people as well as making the results easily visible to anyone who
will take the time to look. Similarly, there are procedures in place
for certain NASA missions which have long time latency, that is, times
during which satellite instruments are being conceived, being built
before they can be flown, and then after the initial flight until the
results can be presented in geophysically meaningful ways. There are
rules promulgated and enforced by NASA on how to make those data
accessible to the public as soon as possible. There are other rules in
place at the National Institutes of Health on molecular, biological,
and genetic data, so-called genebanks, as well as databanks for protein
structures and crystallographic information on the crystals of
proteins. There are additional rules and processes implemented by the
National Science Foundation in certain fields, and these developments,
some of which were summarized in our 2009 data integrity report, are
very impressive and very encouraging. On the other hand, there is
certainly additional financial cost associated with the curating,
archiving, maintaining, and distributing these datasets, some of which
are quite large and heterogeneous in nature.
Accordingly, in response to your question as to whether the Federal
government should withhold funding in various ways, I think the reply
would be more that the Federal government should help to pay for
constructive ways to provide better access to data which were generated
with public funds especially those data which have appeared publicly in
publications, in ways that are compatible with field-by-field standards
that are now being developed. I worry that a one-size-fits-all solution
could turn out to be clumsy and counterproductive. Instead, we require
standards as specific as possible to be applied field-by-field in
recognition of the different kinds, types, values, restrictions, and
volumes of data in each research field.
Thank you for attention to this important issue.
Answers to Post-Hearing Questions
Responses by Dr. Richard S. Lindzen, Alfred P. Sloan Professor of
Meteorology, Department of Earth Atmospheric and Planetary
Science, Massachusetts Institute of Technology
Questions submitted by Representative Ralph M. Hall
Q1a. What is the contribution of clouds to global warming compared
with the contribution of greenhouse gases to global warming?
A1a. Global warming refers to the response to external forcing. Thus,
one doesn't usually refer to clouds as causing global warming. Clouds,
however, can act as feedbacks that could amplify or reduce global
warming. In models, clouds amplify the response, but explicit
measurements suggest that they actually reduce the response.
Q1b. Are the uncertainties in the effects of clouds large enough to
upset model results?
A1b. Doubling CO2 is associated with a 2% change in the
earth's energy budget. Clouds are associated with a 40% contribution to
the earth's energy budget. Thus, small changes in cloud distribution
can easily swamp the contribution of CO2, and uncertainties
as well as identifiable errors in model simulated cloudiness are large.
Q2a. Approximately what percentage of current and expected future
warming is anthropogenic, and what percentage is natural? Is it 50%?
75%?
A2a. At this point, we don't know, but as I noted in my testimony, even
if the answer were 100%, it would still be consistent with small
warming. Remember, we are talking about tenths of a degree. My own work
suggests that about 33% of current warming is anthropogenic. For the
future, this implies that the contribution of added CO2 will
be much less than 1C. No percentages can be offered because the natural
internal climate variability is, itself, not currently predictable.
Q2b. And how much are estimates on this question based on actual
climate observations versus computer modeling?
A2b. High estimates are based on models. Low estimates are based on
observations. All estimates for future are based on either models or
theory.
Q2c. If we don't know the answer to this question with any precision,
how can we have any idea whether policies aimed at addressing projected
warming will have any impact?
A2c. Actually, almost all proposed policies will have so little impact
on levels of CO2, that it is widely acknowledged that they
will have no discernible impact on climate regardless of what one
believes about climate. Only policies that involve almost complete
elimination of fossil fuels will have significant impacts on CO2
levels so that they might have some impact on climate if sensitive
climate models are correct, but this too seems doubtful.
Q3. Some members of the scientific community seem to discount the
affects clouds and aerosols have on global warming. In fact, the IPCC
states that ``Confidence, in attributing some climate change phenomena
to anthropogenic influences is currently limited by uncertainties in
radiative forcing, as well as uncertainties in feedbacks and in
observations.''
a. Can you explain what is currently known and what is not
known about the effect of clouds and aerosols on climate
change?
A3a. The uncertainty in both the nature of aerosols and their
distribution is on the order of a factor of 10. This means that
sensitivity cannot be derived from observed temperature time series. It
also means that there is enough scope for arbitrary adjustment in
aerosols to permit any model to be consistent with any observations. As
to clouds, there is enough known to be confident that all models badly
misrepresent clouds, and that the misrepresentation is sufficient to
swamp anthropogenic influences. Observations of clouds and aerosols are
improving and strongly suggest that many models are exaggerating the
influence of aerosols and that clouds are, indeed, constituting a
negative rather than a positive feedback, and that this negative
feedback is sufficient to dominate the response of the climate system
to anthropogenic forcing..
Q3b. Can you describe the level of uncertainty related to radiative
forcing and feedbacks?
A3b. There is, by now, ample evidence that feedbacks in nature are
negative rather than positive (which is what they are in models).
Radiative forcing by greenhouse gases is reasonably well determined,
but the contribution of aerosols to radiative forcing is poorly
constrained (see previous answer).
Q4. It has been reported that global average temperatures have
increased 0.6+C in the last century.
a. How much of that increase is attributable to each of the
following: natural variability, land-use change, and emissions
of greenhouse gases?
A4a. Precise attribution is currently impossible. What can be said is
that it is possible to simulate the observed change in global mean
temperature anomaly by natural internal variability (ie El Nino,
Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation), and it
is also possible to simulate it with anthropogenic effects--provided
that one is allowed to adjust unknowns like aerosol forcing and solar
forcing arbitrarily. With respect to land use change, it is entirely
possible that it is a significant contributor to the small observed
change in global mean temperature anomaly--as are changes in
instruments and changes in instrument placement.
Q4b. What is the level of uncertainty in each of these answers?
A4b. The commonly stated uncertainty in the temperature record, itself,
is +/- 0.2C. This is probably an underestimate, and already constitutes
a significant part of the total change. As concerns attribution, the
presence of large adjustable factors makes attributions totally
unreliable, though, at least, the attempts to simulate the past with
natural internal variability do not need the egregious adjustments that
the attempts to simulate with anthropogenic forcing need.
Q5a. Do you believe the current IPCC processes are working?
A5a. It depends on what one thinks the purpose of the IPCC is. The
stated purpose is to produce summaries of the research in support of
the negotiating process. Given the intrinsic bias of this purpose, the
IPCC is doing what it is supposed to do. That said, the work of IPCC
working groups II and III is pretty useless since it assumes the worst
for the science and proceeds to spin implausible impacts and responses.
The full Working Group I report on the science is not terrible (though
an index would make it vastly more accessible). Unfortunately, for most
people, however, the only science from Working Group I that they hear
about comes from the press release that accompanies the release of the
Summary for Policymakers (which generally precedes the release of the
full report). For last three reports, the iconic statements have been
that current warming is unprecedented for for 400 years (the infamous
hockey stick), that the balance of evidence points to a human role in
recent warming, and that it is highly likely that man has contributed
most of the warming over the past 50 years. None of these statements
(whether true or not) is actually alarming, but the public is made to
think otherwise.
Q5b. If so, why?
A5b. See preceding answer.
Q5c. If not, what specific actions can be taken to repair them, and in
the meantime, why should the product of a process that isn't working be
relied upon as the basis for policy actions that would impose enormous
costs on the United States economy?
A5c. Frankly, the IPCC reports are not the basis for various proposed
policies. Rather, the IPCC is exploited to claim the existence of a
scientific argument for the proposed policies. Thus, the problem is the
existence of the IPCC, and its statutory authority derived from the Rio
Framework Convention of 1992 plus the fact that policymakers never try
to understand what is actually in the WG I report or even to understand
how vacuous the iconic statements are.
Answers to Post-Hearing Questions
Responses by Dr. Patrick J. Michaels, Senior Fellow in Environmental
Studies, Cato Institute
Questions submitted by Chairman Brian Baird
Q1. Please explain how you get increased levels of black carbon
without also having increased greenhouse gases.
A1. You don't. Black carbon is a result of incomplete combustion of
hydrocarbon fuels or vegetation. My point was that this is not a
greenhouse-gas-induced warming effect, and my point was in response to
EPA's December, 2009 Endangerment Finding in which it states,
Most of the observed increase in global average temperatures
since the mid-20th century is very likely due to the observed
increase in anthropogenic GHG [greenhouse gas] concentrations.
[italics added]
Black carbon is not a gas, nor does it cause an ``observed increase
in global average temperature'' through absorption of upwelling
infrared radiation (i.e. an enhanced greenhouse effect). Whether or not
black carbon is a result of the combustion of fossil fuels is not
germane to this point.
Q2. How is water vapor in the atmosphere not connected to increased
greenhouse gases?
A2. I don't believe I ever stated that. However, there is an emerging
stream of evidence based upon actual observation of what happens in the
atmosphere during major El Nino/La Nina cycles indicating that the
carbon dioxide-water vapor-cloud feedback may have been overestimated,
and even possibly of the wrong sign. (Spencer and Braswell, Journal of
Geophysical Research, 2010, article D16109).
If you are referring to stratospheric (rather than ``atmospheric''
water vapor), Solomon states that she sees variations in stratospheric
water vapor that are not monotonic as are changes in carbon dioxide; in
fact the sign of the relationship with sea surface temperature changes
with time. (Solomon et al., Science, March 5, 2010).
Questions submitted by Representative Ralph M. Hall
Q1. There have been claims that the models and observations of
average surface temperature are in agreement and there have been claims
that they are not. Which is it? Can you explain how they are or are not
in agreement? How do you explain a different interpretation of the
numbers.
A1. I showed in my written and spoken testimony that the IPCC's
midrange suite of models predicts that warming should be taking place
at a constant rate. Indeed, if one looks at the East Anglia temperature
history since 1975, the rate has been remarkably constant.
Mathematically, any departure from a constant rate is not statistically
significant. So the models have the ``form'' of the warming right.
However, if you look at the magnitude of the warming it is clearly
below the mean and median values projected by these models going back
at least 15 years. So you might say that we have the form correct, but
not the size. This latter should be very important to policymakers.
Q2. During the hearing, you and Dr. Santer were engaging in a debate
regarding his 1996 paper. Dr. Santer brought up 3 aspects of the
criticism laid against his paper, specifically: the editorial process
of the scientific journal Nature had been interfered with; the selected
data analysis that showed an upward trend in temperature, and; the
additional scientific work conducted since then that has strengthened
confidence in the ability of the models to reproduce the temperature
change first characterized in the 1996 paper. Unfortunately, time
limitations prevented you from having a chance to respond to Dr.
Santer's claims: Please provide the response to these claims that you
were unable to testify to at the hearing.
A2. Dr. Santer claimed that I stated that the editorial process at
Nature had been interfered with.
I have written much on his 1996 Nature paper. The core error was
using data from 1963 through 1987, when data were available from 1957
through 1995. Using the complete data set completely invalidates his
headline-making finding.
Either peer-reviewers did in fact note this problem and were
ignored, or they simply did not note it, which would mean that each of
the peer-reviewers missed a glaring and obvious error. I can't tell
which it was--perhaps you should ask the appropriate editors at Nature
for the peer reviews and their response. Whatever happened, it was the
most egregious error I have ever seen in a major climate paper.
Santer's claim that our criticism was invalid in using all the data
at the time is simply false. I know of no other word to describe this.
In fact, as is shown in my testimony, the behavior of the important
warm spot in the Southern Hemisphere changes in sign when all the data
are used!
I should point out that Dr. A. H. Oort, of MIT, who assembled the
upper-air record that began in 1957 was in fact one of the co-authors
of the infamous 1996 Santer paper. I think it is impossible to believe
that Oort did not know of the problem. He either mentioned it and was
ignored, or chose not to mention it.
With regard to the timing of the paper, I believe its publication
just days before the Geneva UN conference was no accident. Perhaps the
peer reviewers wanted it rushed to print, perhaps the editors ignored
negative reviews in order to do so . . . we will never know until you
ask Nature.
Q3. In your testimony, you talk about publication bias. That a
substantial number of the papers published today (at least in Science
and Nature) claim that future climate prospects are worse than
previously suggested. How does one regain some balance in a particular
science field's publication rate?
a. Is it appropriate for scientists to encourage or lobby
other-scientists to not publish in a particular journal because
that journal published something that was contrary to their
thinking?
b. Is it appropriate for scientists to conspire to stack
editorial boards so that only one view of a scientific field is
accepted for publication?
c. Is it ethical to then refuse to consider papers for larger
assessments that were not published in popular journals with
skewed editorial boards because their content went against the
``consensus''?
A3. You ask, ``How does one regain some balance in a particular science
field's publication rate''?
My thesis is that an additional finding with regard to a previously
unbiased projection has an equal probability of essentially raising or
lowering the forecast. This is clearly true for weather forecasting
models; climate models share many of their characteristics, as was
noted by other witnesses at your Hearing.
The problem probably lies in the nature of modern science. It is
almost all taxpayer-funded, and individual ``problems'' compete for
finite resources. As a result, the ``problems'' have to be portrayed in
increasingly stark and dire terms, and whole fields are financed upon
the premise of disaster. What incentive is there for anyone to write a
paper that would argue otherwise? What incentive is there for Science,
the journal of the American Association for the Advancement of Science,
to publish such a result? The Association is the scientific community's
Washington lobby. They should be expected to be make it very difficult
to publish anything counter to the interests of its supporters.
You ask if it is appropriate for scientists to encourage their
colleagues to not publish in a journal because it published something
they disagree with. Of course it is not appropriate; in fact it is
deadly wrong and poisons the free exchange of ideas. I think it would
be appropriate for you to ask Dr. Mann of Penn State University this
question. A counter witness should be Chris deFreitas from Auckland
University, whom Mann claimed was inserting papers into the journal
Climate Research that were inappropriate. The two should testify
together, despite the problems with bringing Dr. deFreitas in from New
Zealand.
While it is inappropriate to stack editorial boards in favor of the
disastrous view of climate change, that is the natural result of the
incentive structure, is it not? We spend billions of dollars per year
on this ``problem'', which results in promotion, tenure, and honors at
major Universities. This will never stop until Congress stops feeding
it. Rather, the distortions of science will grow ever larger and
louder.
Of course it is not ethical to bar papers in the peer-reviewed
literature from assessments like those of the IPCC. Even if these
papers were disproven it is important to note their existence, and the
subsequent arguments against them. But, again, is there any incentive
to include things that disagree with the hypothesis that global warming
is a terrible problem?
Q4. Do you believe the current IPCC processes are working? If so,
why? If not, what specific actions can be taken to repair them, and in
the meantime, why should the product of a process that isn't working be
relied upon as the basis for policy actions that would impose enormous
costs on the United States economy?
A4. In a word, ``no''; in two words, ``they can't''. Again it is the
problem of incentives. Congress has been presented with the disaster
that it bought. Corrective action will take much decades, and will
probably impossible to achieve. You will never get a strong counter-
consensus as long as it is professionally dangerous to espouse it. My
profession knows well of the treatment of climate scientists who have
not bought into the apocalyptic view of climate change.
I would not rely on any of these large-scale assessments unless the
editorial panels showed some semblance of balance--but again, that is
very difficult to achieve this given that the professional rewards
handed out on one side, while punishment is meted out to the other. .
Answers to Post-Hearing Questions
Responses by Dr. Benjamin D. Santer, Atmospheric Scientist, Program for
Climate Model Diagnosis and Intercomparison, Lawrence Livermore
National Laboratory
Questions submitted by Chairman Brian Baird
Terminology--climate change versus global warming
Some people are unclear or unhappy about the use of ``climate
change'' instead of the less-precise term ``global warming.''
Q1. Can you explain why ``climate change'' is a more accurate
representation of the phenomenon?
A1. ``Global warming'' is a potentially misleading term. In my opinion,
use of the term ``global warming'' implies two different expectations
about the ``climate signal'' arising from human-caused changes in the
atmospheric concentrations of greenhouse gases. The first is that
climate scientists expect every location on Earth's surface--and every
layer of Earth's atmosphere and oceans--to warm in response to human-
caused changes in greenhouse gases. The second is that climate
scientists expect each year to be successively warmer than the previous
year (in some global average sense).
Neither expectation is correct.
Consider first the ``every location should warm'' expectation.
Since the late 1980s, climate scientists have known that this
expectation is incorrect. Pioneering work at a number of different
research groups around the world (1, 2, 3, 4, 5, 6) helped scientists
to understand the complex of effects of sulfate aerosol particles on
climate.
The main source of sulfate aerosols is fossil fuel burning (7).
Sulfate aerosols affect climate in two ways--by direct scattering of
incoming sunlight back to space, and by influencing the optical
properties and lifetime of clouds. In areas where the atmospheric
burdens of sulfate aerosol particles are high, they can cause local or
regional cooling of the Earth's surface.\1\ The cooling effects of
sulfate aerosols on surface temperatures have been identified in many
different ``fingerprint'' studies, which involve rigorous statistical
comparisons of modeled and observed patterns of climate change (8, 9,
10, 11, 12, 13, 14, 15).
---------------------------------------------------------------------------
\1\ Because of the dynamic nature of the atmospheric general
circulation, sulfate aerosols can also induce ``far field'' climate
effects, at locations remote from regions where there are high
atmospheric burdens of sulfate aerosol particles. The IPCC Fourth
Assessment Report (7) concluded that the best current estimate of the
radiative forcing associated with the direct scattering effects of
sulfate aerosols is ^0.4 0.2 Wm-2. The indirect effects of
sulfate aerosols on clouds are more uncertain.
---------------------------------------------------------------------------
The local and regional-scale cooling caused by sulfate aerosols is
occurring against the backdrop of the broad, global-scale surface
warming arising from human-caused changes in greenhouse gases.
Other human influences can also have important local or regional
effects on climate. Examples of such influences include human-caused
changes in black carbon aerosols (which cause warming), and in the
properties of the land surface (which can cause either cooling or
warming, depending on the nature of the modification to the land
surface) (7).
The bottom line is that human effects on climate are complex over
space and time. The human-caused climate change ``fingerprint'' is a
mixture of climate forcings which cause global-scale warming of the
Earth's surface (like changes in well-mixed greenhouse gases) and
forcings which cause local to regional-scale surface cooling (like
changes in the atmospheric concentrations of sulfate aerosols). In a
global average sense, the net human-caused forcing of climate is
positive. The warming effects of greenhouse gases and soot aerosols
more than compensate for the cooling influences of sulfate aerosols,
other reflective aerosols, and land use changes (7). But at individual
locations--such as in heavily-polluted areas, where atmospheric burdens
of sulfate aerosols are large--the cooling effects associated with
negative forcing factors can predominate. Thus the term ``global
warming'' does not capture the very complex nature of human effects on
climate, and does not convey the message that even local or regional
surface cooling can be human-induced.
As I mentioned above, ``global warming'' also implies that each
year will be inexorably warmer than the previous year. This is not what
climate scientists expect to observe.
Climate change is not an either/or proposition--either all due to
human factors, or all due to natural causes. It is due to both human
and natural factors. The human-caused climate change ``signal'' is
embedded in the background ``noise'' of natural climate variability.\2\
As has been recognized since the late 1970s, identifying human effects
on climate is a signal-to-noise problem (16), requiring the application
of signal processing techniques similar to those used in electrical
engineering.
---------------------------------------------------------------------------
\2\ This ``climate noise'' has both externally-forced and
internally-generated components. The externally-forced contributions to
``climate noise'' are caused by natural changes in 1) the Sun's energy
output; and 2) the amount of volcanic dust in the atmosphere. The
internally-generated component of ``climate noise'' arises from natural
oscillations of the coupled atmosphere-ocean-sea ice system. Examples
of such ``unforced'' oscillations include El Ninos and La Ninas, the
Pacific Decadal Oscillation, and the Atlantic Decadal Oscillation.
---------------------------------------------------------------------------
Because of the effects of climate noise, we do not expect each year
to be warmer than the preceding year. For example, during a year with a
large La Nina event, climate scientists expect global-mean surface
temperature to be slightly cooler than average. One could not infer
from a single cool ``La Nina'' year that the gradual warming of the
Earth's surface over the past 150+ years had ceased!
This is why climate scientists look at signal-to-noise behavior
over many decades rather than over very short periods (10 years or
less). Over longer periods of time (decades to centuries), there are
larger changes in the human-caused factors which influence climate,
leading to larger climate-change ``signals''. Furthermore, the
``climate noise'' in most meteorological and oceanographic time series
tends to be largest on year-to-year timescales, and becomes smaller
over longer averaging periods (17, 18). So when analysts search for a
human effect on climate, they focus their attention on long, multi-
decadal records, with more favorable signal-to-noise ratios.
If there were more widespread understanding of such basic signal-
to-noise concepts, little attention would be paid to invalid claims
that a single cool year--or even a single cool decade--provided
``evidence of absence'' of a human effect on climate.
The key point here is that even in the presence of strong human-
caused ``forcing'' of the climate system, natural climate variability
will continue. Because of this natural variability, each of the next 90
years in the 21st century will not be warmer than the preceding year--
which is the expectation that ``global warming'' conveys.
IPCC reliable information
Q1. Based on your experience as a contributor to four previous IPCC
assessments, do you regard the IPCC as an effective means of providing
policymakers with reliable information on the nature and causes of
climate change?
A1. Yes.
First let me explain why I believe I am qualified to answer this
question.\3\ I contributed to all four Scientific Assessment Reports of
the Intergovernmental Panel on Climate Change. I served as Convening
Lead Author of Chapter 8 of the 1995 IPCC Second Assessment Report
(19).\4\ I was also a Contributing Author to the ``Detection and
Attribution'' chapters of the IPCC's First, Third, and Fourth
Assessment Reports.
---------------------------------------------------------------------------
\3\ I note that many of the public commentators on the reliability
of the scientific information provided by the IPCC have little or no
direct IPCC experience.
\4\ This chapter was entitled ``Detection of Climate Change and
Attribution of Causes''. Chapter 8 concluded that ``the balance of
evidence suggests a discernible human on global climate''. After
publication of the Second Assessment Report in 1996, I spent over a
year of my scientific career defending the ``discernible human
influence'' finding, and defending the process by which this finding
had been reached.
---------------------------------------------------------------------------
Since its inception in 1988, the IPCC--and many climate scientists
who have worked in its service--have been the subject of much
unjustified criticism. I'd like to briefly address three areas of
criticism. All relate to issues I am directly familiar with.
``Political interference'' and ``scientific cleansing'' allegations
After publication of the IPCC's Second Assessment Report (SAR),
parties critical of the IPCC's finding of a ``discernible human
influence'' on global climate alleged that Chapter 8 of the SAR had
been modified for political purposes, and ``cleansed'' of all
scientific uncertainties. Such allegations are baseless. They have been
rebutted in many different fora. Chapter 8 was not subjected to
``political tampering'' or ``scientific cleansing''. Changes made to
Chapter 8 after the November 1995 IPCC Plenary Meeting in Madrid were
made for scientific reasons, not for political reasons. Changes were in
response to Government review comments and to the scientific
discussions which took place in Madrid.
Unfortunately, some individuals have persisted in resurrecting
these false ``political tampering'' and ``scientific cleansing''
allegations. My response to these allegations (and the IPCC's response)
is a matter of public record.\5\
---------------------------------------------------------------------------
\5\ http://www.realclimate.org/index.php/archives/2010/02/close-
encounters-of-the-absurd-kind/
Accommodation of the ``full range of scientific views''
Some parties critical of the IPCC have claimed that the IPCC does
not accommodate the full range of scientific views on the subject of
the nature and causes of climate change. In my opinion, such claims are
specious. I would contend that IPCC Scientific Assessment Reports have
dealt with alternative viewpoints in a thorough and comprehensive way.
For example, the IPCC has devoted extraordinary scientific attention to
a number of highly-publicized claims. Examples include the claim that
the tropical lower troposphere cooled over the satellite era; that the
water vapor feedback is zero or negative; that solar irradiance
variations explain all observed climate change. The IPCC and the
climate science community have not dismissed these claims out of hand.
Scientists have performed the research necessary to determine whether
these ``alternative viewpoints'' are scientifically credible. They are
not.
Furthermore, I note that holders of these ``alternative
viewpoints'' are often directly involved in the IPCC process, either as
Lead Authors or reviewers.
Openness and data sharing
Another frequent criticism relates to data sharing, particularly
with regard to model data. This issue is discussed in my written
testimony of November 17, 2010.
The database of coupled model output produced in support of the
IPCC's Fourth Assessment Report (FAR) has transformed the world of
climate science. At present, 35 Terabytes of data from the so-called
CMIP-3 project are archived at Livermore, and nearly 1 Petabyte of data
has been distributed to well over 4,300 users. To date, over 560 peer-
reviewed publications have used CMIP-3 data. These publications formed
the scientific backbone of the IPCC FAR. There is no substance to the
criticism that the IPCC is some kind of ``closed shop'', and does not
open its doors to detailed scrutiny of the climate model data used in
its Assessment Reports.
``Groupthink''
Several public critics of the IPCC have argued that it engages in
``groupthink''. I fundamentally disagree with this criticism.
My own personal experience of the IPCC (obtained during my service
as a Convening Lead Author and Contributing Author) is that the IPCC,
like other scientific assessments, brings together a very diverse group
of experts, with a diverse set of skills and knowledge. IPCC Lead
Author meetings are the antithesis of ``groupthink'' encounters.
Participants in such meetings do not engage in continuous self-
congratulatory behavior. They behave like scientists at any other
scientific meeting. They challenge accepted wisdom and orthodoxy. They
revisit old academic debates and rivalries. They are combatants in an
arena of scientific facts and theories. They argue over the robustness
of different analysis methods and findings. They debate the strengths
and weaknesses of simple and complex numerical models. They struggle to
quantify and reduce scientific uncertainties. They spend many hours
trying to explain difficult technical issues in plain English, trying
to capture what is known with confidence and what is not.
Anyone who has witnessed such IPCC Lead Author meetings would never
use the word ``groupthink'' to describe them.
In summary, I believe that the IPCC is the best mechanism we have
for providing policymakers with reliable information on the nature and
causes of climate change, the likely impacts of climate change, and
possible mitigation and adaptation strategies. The scope and rigor of
IPCC assessments is extraordinary.
Yet the IPCC is not infallible. Inaccurate information can make its
way into an IPCC Report, despite exhaustive review procedures. Several
inaccuracies in a 1,000-page Report do not undermine the entire science
of climate change. The IPCC is working hard to further improve its
review procedures, and to guard against the inclusion of erroneous
information in subsequent Assessment Reports.
Peer review process
You noted in your testimony, ``Extraordinary claims demand
extraordinary proof.'' The scrutiny and study of climate change has
been extraordinary.
Q1. Are most scientific claims subject to the same amount of
scientific rigor and review before they are considered affirmed? Less?
A1. The IPCC's claim that ``most of the observed increase in global
average temperatures since the mid-20th century is very likely \6\ due
to the observed increase in anthropogenic greenhouse gas
concentrations'' (20) has indeed been subjected to extraordinary
scrutiny. In my opinion, most scientific claims are not subject to a
similar degree of review ``before they are considered affirmed''.
---------------------------------------------------------------------------
\6\ Where the term ``very likely'' signified >90% probability that
the statement is correct.
---------------------------------------------------------------------------
At its core, science is about reproducibility. Findings of a
``discernible human influence'' on global climate have been
independently reproduced by many research groups around the world.
As I noted in my testimony of November 17, 2010, climate scientists
have now analyzed changes in many different components of Earth's
climate system. They have looked at surface and atmospheric
temperature, ocean heat content, Atlantic salinity, sea-level pressure,
tropopause height, rainfall patterns, atmospheric moisture, continental
river runoff, and Arctic sea-ice extent. The general conclusion is that
for each of these variables, natural causes alone cannot explain the
observed climate changes over the second half of the 20th century. The
best statistical explanation of the observed changes invariably
involves a large human contribution. These results are robust to the
processing choices made by different groups, and show a high level of
physical consistency across different independently-monitored climate
variables.
Findings of a ``discernible human influence'' on global climate do
not rest on a single observational dataset, a single scientific study,
or a single scientific assessment, as some uninformed commentators have
claimed. Such findings are subject to multiple review phases during the
course of developing an IPCC report. These review phases involve
literally hundreds of climate scientists.
I would like to contrast this rigorous review of IPCC findings with
the apparent absence of detailed peer review of the material presented
to the House Science and Technology Committee by Professor Patrick
Michaels. In his written testimony of November 17th, 2010, Professor
Michaels showed an analysis of the causes of changes in global-average
temperature over 1950 to 2009. He claimed that this analysis does not
support the IPCC's 2007 finding that ``most of the observed increase in
global average temperatures since the mid-20th century is very likely
due to the observed increase in anthropogenic greenhouse gas
concentrations'' (20). If Professor Michaels' claim were correct, and
if the analysis he presented were sound, it would be a very serious
matter.
Prior to casting doubt on one of the central findings of the IPCC's
Fourth Assessment Report, most scientists would ensure that their work
was subjected to rigorous review by their peers. They would check that
their data, analysis methods, and inferences were sound.
Yet despite the extraordinary nature of the claim made in his
testimony, Professor Michaels provides no information on the source of
his analysis of the causes of global-mean temperature changes. It is
unclear where (or even whether) his analysis has been published. He
does not give any description of the method he used in subtracting the
effects of four different factors \7\ from an observed record of
global-average temperature change. There is no discussion or treatment
of uncertainties in his selected method of removing ``non-
CO2'' warming influences from observational data. His
analysis provides no error bars.
---------------------------------------------------------------------------
\7\ The four factors identified by Professor Michaels were 1)
errors in sea-surface temperature data; 2) ``non-climatic influences;
3) stratospheric water vapor changes; and 4) changes in black carbon
aerosols.
---------------------------------------------------------------------------
One asymmetry is particularly troubling. Professor Michaels argues
that black carbon aerosols--which cause net warming--are important. The
warming effects of these soot aerosols are included in his analysis of
the factors contributing to global-mean temperature change. However,
Professor Michaels does not account for the cooling effects of sulfate
aerosols. These cooling effects have been studied for over 20 years by
dozens of research groups around the world (see response to ``Questions
for the Record'' #1).
Professor Michaels does not provide a rigorous quantitative
assessment of the contributions of different forcing factors to
observed global-mean temperature changes. His analysis serves to
highlight the differences between the thoroughly reviewed IPCC claim of
a ``discernible human influence'' on global climate, and Professor
Michaels' unreviewed claim of a very small human impact on climate.
References
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2 Charlson, R.J., J. Langner, and H. Rodhe, 1990: Sulfate
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Warren, 1991: Perturbation of the Northern Hemisphere radiative
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E. Roeckner, R. Voss, and J. Waszkewitz, 1997: Multi-
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Answers to Post-Hearing Questions
Responses by Dr. Judith A. Curry, Chair of the School of Earth and
Atmospheric Sciences, Georgia Institute of Technology
Questions submitted by Representative Ralph M. Hall
I would like to thank the Committee for this opportunity to expand
upon my testimony. I found the questions to be particularly insightful
and profound. The answers to these questions about a very complex
situation are not simple or straightforward. In preparing my answers to
these questions, I sought input from participants in my blog Climate
Etc. (at http://judithcurry.com/2010/12/03/testimony-follow-up/), which
received 265 comments from a diverse group of scientists, other
professionals and anonymous citizens, from the U.S. as well as
internationally. The diversity of opinions and ideas regarding these
questions is evidenced by the broad range of thoughtful and insightful
viewpoints expressed on the blog, and I acknowledge the contributions
expressed on my blog in preparing this statement.
Q1. It is clear from your public statements that you generally agree
with the mainstream view of global warming and cannot easily be
characterized as a climate change ``denier'' or ``skeptic.''
Nonetheless, you have been quite critical of the process under which
climate science is conducted, saying that ``it is difficult to
understand the continued circling of the wagons by some climate
researchers with guns pointed at skeptical researchers by apparently
trying to withhold data and other information of relevance to published
research, thwart the peer review process, and keep papers out of
assessment reports.''
a. Why are so many scientists ``pointing their guns'' at
skeptics when sharing data and embracing debate seems to be an
obvious way for scientists to increase the credibility of their
arguments and influence public debate?
A1a. While the majority of climate scientists are not engaged in these
adversarial tactics, the CRU emails revealed a siege mentality adopted
by a group of influential and highly visible climate researchers.
Understanding how and why this situation evolved in the way it did is a
topic that should be investigated by historians and sociologists of
science.
My own understanding of this is described in the context of the
IPCC/UNFCCC ideology. What I'm referring to as the IPCC/UNFCCC ideology
is described in my blog post at http://judithcurry.com/2010/11/07/no-
ideologues-part-iii/ and is apparent in this interview with Michael
Mann http://bos.sagepub.com/content/66/6/1.full. The basic elements of
this ideology are outlined as:
1. Anthropogenic climate change is real.
2. Anthropogenic climate change is dangerous and we need to
something about it.
3. The fossil fuel industry is trying to convince people that
climate change is a hoax.
4. Deniers are attacking climate science and scientists, and
their disinformation is misleading the public.
5. Deniers and the fossil fuel industry are delaying UNFCCC
mitigation policies, providing a political motivation to
counter the disinformation from the deniers.
The book ``Merchants of Doubt'' by Oreskes and Conway describes
``how a loose-knit group of high-level scientists, with extensive
political connections, ran effective campaigns to mislead the public
and deny well-established scientific knowledge over four decades. . .
showing how the ideology of free market fundamentalism, aided by a too-
compliant media, has skewed public understanding of some of the most
pressing issues of our era.'' The ``circling the wagons'' strategy
revealed in the CRU emails was designed to counter the tactics of the
merchants of doubt and other deniers in delaying the UNFCCC mitigation
policies. This strategy was apparently designed under the tutelage of
advocacy groups, learning lessons from the wars with big tobacco, etc.
While free market fundamentalism and ``big oil'' may have been a
major source of skepticism in the past, the current dominant group of
skeptics, enabled by the blogosphere, seeks accountability. Many of
these skeptics have professional backgrounds and extensive experience
with the practical application of science and regulation, without any
particular political motivations and certainly without funding from
``big oil.'' Failing to recognize this new breed of climate skeptics,
and dismissing them as politically motivated deniers or merchants of
doubt, led to the events that were revealed by the CRU emails.
An additional motivation for circling the wagons seems to be
insecurity and fear that uncertain or flawed analyses will damage
professional reputations, as a result of this extraordinary scrutiny of
their research. This motivation is revealed by Phil Jones' email to
Warwick Hughes saying: ``Why should I give you my data when you only
want to find fault in it?'' Scientists who have invested considerable
work and their professional reputations in developing a certain line of
research want to be ``right'', and defend their research against
challenges from skeptical researchers. The normal process of scientific
debate eventually sorts things out. However, when the battle lines were
drawn between the ``virtuous'' scientists and the anti-science deniers,
other scientists lined up in a ``consensus'' to fight against the
forces of anti-science, without a careful examination of the scientific
issue at hand. The end result is that genuine skeptical arguments were
marginalized and ignored, which diminishes the credibility of science
that is being defended.
Another issue is the evolving importance and changing dynamic of
climate research. Two decades ago, climate science was conducted in a
purely academic environment and there were no data quality requirements
or regulatory requirements for models. As climate science has become
increasingly policy relevant, demands on quality and traceability
(particularly retrospective ones) could not be met. This produced
defensiveness amongst the scientists, who did not want to provide any
ammunition for the merchants of doubt; they sought refuge in the
``consensus'' and argued by appealing to their own authority.
In the midst of all this, scientific best practices became
compromised.
b. Given the potentially enormous influence of climate science
on economic and environmental policy--which ultimately boils
down to jobs--shouldn't it be held to a higher standard in the
public debate? For example, should Congress consider blocking
funding for researchers that do not make their data and
materials available for public scrutiny?
A1b. The key issue is openness and traceability. Scientists supported
by government funding should ensure that their data and methods are
made available to any researcher for purposes of replication. However,
the practical aspects of wholesale enforcement of this are not
straightforward. U.S. agencies that supervise and fund climate research
(e.g. USGCRP, NSF, NOAA, NASA) already have substantial requirement in
place for data archival and full and open access to data. Many journals
also have requirements for archiving data and ensuring that the data
and methods used are made available for purposes of replication. These
requirements are not uniformly enforced. How to enforce these
requirements in a cost effective way is an important topic to address.
Climate science used for public policy should be held to a higher
standard, in a manner similar to medical/pharmaceutical research that
is used in the health marketplace. There is normal academic peer
reviewed medical research, but higher standards are required in the
context of regulated science before a drug or procedure can be
marketed. The analogy for climate science is normal academic peer
reviewed science, versus an accountable assessment process for policy
makers. As part of the assessment process, greater accountability is
required, which might consist of fact checking, statisticians auditing
the statistical methods, computer scientists auditing the algorithms,
etc.
With regards to funding, as part of the proposal process,
scientists should state how they will archive their data or otherwise
make available data and other information to others attempting to
reproduce their results. Scientists should be held accountable for
actually having made their data available in consideration for future
funding. I am aware of some funding programs and program managers that
actually do this, but overall this does not seem to be enforced.
The principal climate data records should be maintained by
government agencies, with full documentation, quality and version
control, complete documentation, and support to respond to user
queries. University research groups are ill equipped to handle this,
and researchers generally find the painstaking work of quality control
to be scientifically boring.
c. Should such research be excluded from use in policy debates
and scientific assessments such as those by the National
Academies or IPCC?
A1c. There is no prima facie reason to exclude any relevant information
from policy and scientific debates. The ``scientific juries'' of the
IPCC and National Academies will use their own standards to decide
which scientific studies are suitable for inclusion in their assessment
reports. However, there is a significant gap between a scientific
assessment of research and accountable information for actual policy
making and regulatory purposes. Accountability for issuing regulations
under the EPA endangerment finding could demand that all relevant
information be independently assessed for its accuracy and reliability
to determine its usefulness. Information that has not been assessed or
cannot be assessed owing to unavailability of data and other source
materials would not be used in this context. Such a requirement would
motivate the science community to ensure that its products are useful
in the context of policy making and government regulations.
Q2. You state in your testimony that the conflict regarding the theory
of anthropogenic climate change is over the level of our ignorance
regarding what is unknown about natural climate variability. For a long
time, the scientific community did not consider uncertainty a bad
thing. In fact, the word ``certainty'' was something that was almost
never used (you are not certain the sun will rise tomorrow morning, but
you are reasonably sure that it is very likely to occur).
a. At what point did uncertainty become a bad thing in the
climate community?
A2a. Uncertainty became a bad thing in the climate science community
with the creation of the UN Framework Convention on Climate Change
(UNFCC) Treaty in 1992. The UNFCCC states that future greenhouse gas
emissions are uncertain, as are climate change damages. However,
following the precautionary principle, ``lack of full scientific
certainty shall not be used as a reason for postponing cost-effective
measures to prevent environmental degradation.'' While lack of full
certainty does not preclude action, the level of certainty needs to
reach some sort of threshold before action is triggered under the
precautionary principle. While this threshold of certainty is vague,
reducing the uncertainty makes action more likely.
In the 1980's and 1990's, climate research programs were aimed
explicitly at the reduction of uncertainties in future climate
projections. By the mid 1990's, climate modelers were beginning to
realize that the increasing complexity of climate models and the
fundamentally chaotic nature of climate system precluded full
predictability of the climate system. Nevertheless, the emphasis from
policy makers and funding agencies was on the reduction of uncertainty.
The U.S. Climate Change Science Program Science Plan (published in
2003) emphasized reducing uncertainty, using the phrase in many of its
goals.
Classical decision making theory involves reducing uncertainties
before acting. There has been a growing sense of the infeasibility of
reducing uncertainties in global climate models owing to the continued
emergence of unforeseen complexities and sources of uncertainties.
While reducing the overall uncertainty isn't viable, at the same time
not acting could be associated with catastrophic impacts. Since a
higher level of confidence would make decision makers more willing to
act, political opponents to action sold doubt and the scientists
countered by selling certainty and consensus. Scientific statements
about uncertainty became viewed as political statements.
b. How did this shift within the scientific community occur?
How does it shift back?
A2b. Climate science got caught up in a highly charged political
debate: the consequences predicted by the models were dire, and many of
the climate scientists were persuaded by the predictions of the models.
Climate science is a relatively young field, and one that was ill
prepared for participation in such a highly charged political debate.
The traditions of science in disclosing all of the weaknesses of their
work were at odds with this adversarial political process.
The actual shift within the community seems to have occurred in the
context of the IPCC process. The entire framing of the IPCC was
designed around identifying sufficient evidence so that the human-
induced greenhouse warming could be declared unequivocal, and so
providing the rationale for developing the political will to implement
and enforce carbon stabilization targets in the context of the UNFCCC.
National and international science programs were funded to support the
IPCC objectives. Scientists involved in the IPCC advanced their
careers, obtained personal publicity, and some gained a seat at the big
policy tables. This career advancement of IPCC scientists was done with
the complicity of the professional societies and the institutions that
fund science. Eager for the publicity, high impact journals such as
Nature, Science, and PNAS frequently publish sensational but dubious
papers that support the climate alarm narrative. Especially in
subfields such as ecology and public health, these publications and the
media attention help steer money in the direction of these scientists,
which buys them loyalty from their institutions, who appreciate the
publicity and the dollars. Further, the institutions that support
science use the publicity to argue for more funding to support climate
research and its impacts. And the broader scientific community
inadvertently becomes complicit in all this. When the IPCC consensus is
attacked by deniers and the forces of ``anti-science,'' scientists all
join in bemoaning these dark forces fighting a war against science, and
support the IPCC against its critics. The media also bought into this,
by eliminating balance in favor of the IPCC consensus.
The bottom line is that scientists worked within the system to
maximize their professional reputations, influence, and funding. Rather
than blame the scientists for optimizing their rewards within the
system, we need to take a careful look at the system, most particularly
the climate science-policy interface and the federal funding of climate
science.
How does it shift back? Change the system to improve the science-
policy interface and change the funding priorities. A top priority for
research funding should be exploring the significance and
characteristics of uncertainty across the range of climate science, not
only the climate models themselves, but also solar forcing, surface
temperature datasets, natural internal modes of climate variability,
etc. Change the decision making framework from the classical ``reduce
the uncertainty before acting'' paradigm to a robust decision making
framework that incorporates understanding of uncertainty as information
in the contemplation and management of environmental risks.
Changing the funding priorities is key. We need to reduce reliance
on building ever more complex climate models for being the primary
source of reducing uncertainties regarding climate change. Climate
researchers need to engage with a broader range of expertise in and
build strong links to disciplines experienced in complex nonlinear
modeling and statistical inference, among others. We need a much better
understanding of natural climatic variability. More research is needed
on understanding abrupt climate change and developing a more extensive
archive of paleoclimate proxies. And finally, greater resources need to
be provided to accelerating the establishment of definitive climate
data records.
Openness and transparency enables critical examination by a broad
range of scientists and citizens. Recognition of the extended peer
review communities enabled by the blogosphere is essential, and frank
discussions with skeptics are needed. We need to eliminate the elitism
that argues that certain scientists are more ``important'' voices in
the debate than others (by virtue of their academic recognitions,
citations, etc), that scientists with expertise outside of the
traditional climate disciplines can be ignored, and that the only valid
contributions come in the form of peer reviewed journal publications.
With regard to the latter point, well-documented analyses/audits of
data sets occurring on technical blogs have provided significant
contributions to understanding and improving data quality. This elitism
is counter to the traditions of science, characterized by physicist
Richard Feynman as ``Science is the belief in the ignorance of the
experts.'' It is the merits of the scientific argument that count; not
the qualifications of the person making the argument.
c. Are there any efforts within the scientific community to
self-correct this paradigm shift? If there is not, what does
this mean for the decision-makers needing objective and
unbiased scientific information to inform their policies?
A2c. Science is subject to human fallibility, and such shifts have
happened in the past. Science always manages to correct itself, but the
process is not necessary quick or painless. Scientific professional
societies and universities have a key role to play in setting the
standards for scientific research and for establishing a useful
interface between science and policy.
That said, the first reaction of the climate establishment to the
release of the CRU emails and the errors identified in the IPCC reports
has generally been one of defensiveness, and lacking introspection and
discussion of correction. Some of the climate scientists at the center
of ``storm'' seem to be battling a scientific version of post traumatic
stress syndrome, overwhelming their ability to cope with the issues.
Dealing with these issues requires active involvement by the broader
climate research community and particularly by the institutions that
include climate researchers but are not dominated by them, including
the American Geophysical Union, the American Association for the
Advancement of Science, the National Academies.
If the government wants objective and unbiased scientific
information to inform their policies, then the guidelines and
incentives need to be changed. Stop asking for scientists to reduce the
uncertainties; rather, ask for our understanding of the range of risks
that we might be facing from climate change (both natural and
anthropogenic). Fund climate research that is much broader, not just
studies designed to support the IPCC/UNFCCC. Support the development of
improved connections with disciplines that conduct research into
complex nonlinear systems, statistical inference, and decision making
under uncertainty. Change the nature of the ``carrot'' and the
scientific community will respond.
Finally, I have to state that my own efforts to stimulate such a
correction have been highly controversial within the field of climate
research, and relatively few climate researchers are speaking out
publicly in support of what I am trying to do. I regard my own
scientific reputation as secure, as well as my research funding, so I
don't feel that I am risking anything that I can't afford to lose by
speaking out. But other scientists feel much more vulnerable if they
were to attempt to rock the boat in some way, and I have received many
emails from scientists expressing this kind of concern. This culture
that has developed in climate science that greatly concerns me,
particularly in the context of university departments and government
labs. Ten years ago, I used to think that university tenure was
irrelevant in my field. Right now, the controversy surrounding climate
science makes tenure seem essential. Scientific debate should be the
spice of academic life; climate research lost this in the midst of the
politicization of the subject.
Q3. Do you believe the current IPCC processes are working? If so, why?
If not, what specific actions can be taken to repair them, and in the
meantime, why should the product of a process that isn't working be
relied upon as the basis for policy actions that would impose enormous
costs on the United States economy?
A3. A number of people have put forth arguments that the IPCC is
structurally unsound and fatally flawed, owing to its connection with
the UNFCCC. Some people who have been supportive of the IPCC view its
work as being finished. I view the major flaws of the IPCC to be:
A focus on providing scientific information on
anthropogenic climate change for use as justification of a
Treaty, at the expense of a thorough assessment of natural
climate variability, the limitations and uncertainties
associated with climate model projections, etc.
The requirement for broad based international
participation in the IPCC assessment, resulting in a heavy
emphasis on participation by scientists that are merely
industrious rather than those that are exceptionally qualified,
experienced and insightful. Compare the list of authors on the
IPCC AR4 report with those involved in the 1979 Charney Report
on Carbon Dioxide and Climate, which included the premier U.S.
scientists of the time. The broad geographical and
international distribution of authors, some with relatively
meager qualifications and experience, seems motivated more by
political reasons to gain support for the Treaty rather than by
the needs of the scientific assessment itself.
Working Groups II and III on impacts and mitigation
have produced reports that are judged by many to be inaccurate
and misleading. The emphasis of these reports seems to be to
convince policy makers that anthropogenic climate change is
dangerous and the problem of carbon mitigation can be addressed
feasibly and without economic damage.
So in one sense, the IPCC process is ``working'' in terms of
garnering support for the UNFCCC treaty. But as a scientific assessment
of climate variability and change and the vulnerabilities to climate
change, I would judge the IPCC process not to be working. I don't think
that the IPCC can be repaired without a major overhaul of its
justification and organization. For an IPCC under the auspices of the
UN, I would recommend that the WG I assessment be undertaken under the
auspices of the WMO/WCRP (and not the UNEP and UNFCCC).
Many other initiatives with international implications are
undertaken without the involvement of the UN. An approach whereby
disparate organizations conduct assessments would be beneficial,
producing new ideas and new directions and a more diverse scientific
and policy debate. An alternative to the IPCC is to conduct assessments
within individual nations or a group of nations who share a common
interest. However, the recent U.S. assessment reports seem to mostly
parrot the IPCC assessment, with many of the people participating in
the U.S. assessments having also participated in the IPCC. A broader
base of scientists should participate in the assessments, including
those whose scientific reputations and funding aren't tied to climate
change. Skeptical perspectives should be sought and included.
Regarding use of the scientific assessments as a basis for policy
actions, I argue that an intermediate step is required, analogous to
that for regulated science such as pharmaceuticals, food safety, human
genetic manipulation, etc. Independent assessment, auditing, due
diligence, whatever you want to call it, can insure that quality
standards are met and that the assessment addresses the wider interests
of the public.
There are no simple answers to addressing the complex and wicked
problem of climate change, but a rethinking of our broader strategies
is needed.