U.S. Senate Committee on Environment & Public Works
U.S. Senate Committee on Environment & Public Works
Hearing Statements
Date:   07/08/2003
Sen. Thomas R. Carper, of Delaware
Agricultural Sequestration of Carbon Dioxide

To our witnesses, good morning, and thank you for being here today. To our Chairman, Senator Voinovich, good morning.

I am pleased that we have before us some experts on the issue of carbon sequestration who can help us better understand the risks and benefits of one of the more common methods mentioned to address rising atmospheric CO2 levels.

There is a growing consensus that greenhouse gases such as CO2 emissions from power plants are contributing to climate change. The time has come to set up mechanisms that will address these emissions without impeding economic growth. By establishing a modest goal of capping CO2 emissions from electrical generators at 2001 levels by 2012, we can begin go make progress. Generators can meet such a goal with a flexible system that includes agricultural sequestration.

I am pleased to see that so many of our witnesses, in their testimony, say that we can take steps to reduce levels of CO2, and even more importantly, they say that we should do so.

At recent subcommittee meetings I have questioned witnesses, and even members of the Committee, about the Administration’s plan to reduce ‘Greenhouse Gas Intensity by 18 percent’, and I think I have made it clear that I don’t consider that an adequate goal.

I think it is interesting that according to the White House’s “Global Climate Change Policy Book, Addendum” from 2002 - total U.S. greenhouse gas emissions in 2012 that can be expected from meeting the 18 percent emission intensity, measured in tons reduced per dollar of GDP- in 2012 would be 13 percent over the estimated 2002 emissions.

Jim Connaughton, The Chairman of the Council on Environmental Quality said, during a Commerce Committee hearing in 2002, that under the Administration's emissions intensity approach total CO2 emissions will continue to rise.

Lets agree that we should do more than the Administrations plan. The question for us is how to move forward in addressing this challenge.

I look forward to today’s testimony, and will have a few questions for our witnesses.

ATTACHMENT 1 World Meteorological Organization—A Specialized Agency of the United Nations For use of the information media - WMO-No 695



Geneva, 2 July 2003 - Record extremes in weather and climate events continue to occur around the world. Recent scientific assessments indicate that, as the global temperatures continue to warm due to climate change, the number and intensity of extreme events might increase, the World Meteorological Organization (WMO) states in a press release issued today.

In June, record high temperatures were recorded across southern France, with maximum temperatures exceeding 40°C in parts of southwest France. This resulted in June average temperatures of 5 to 7°C above the long-term average. In Switzerland, the month of June was the hottest in at least the past 250 years, according to environmental historians. In Geneva, since 29 May, maximum daytime temperatures did not drop below 25°C, making June the hottest June on record for the city.

In the United States, there were 562 tornados during May, which resulted in 41 deaths. This established a record for the number of tornados in any month. The previous monthly record was 399 tornados in June 1992. In the eastern and southeastern part of the US, wet and cold conditions prevailed for well over a month. Weekly negative temperature anomalies of –2°C to –6°C were experienced in May while precipitation excesses, ranging from 50 mm to 350 mm over a period of more than 12 weeks starting in March 2003, have been recorded.

In India, this year’s pre-monsoon heat wave brought peak temperatures of between 45°C and 49°C which correspond to weekly temperature departures from the normal of +2 to +5°C. At least 1400 people died in India due to the hot weather. In Sri Lanka, heavy rainfalls from Tropical Cyclone 01B exacerbated already wet conditions, resulting in flooding and landslides and killing at least 300 people. The infrastructure and economy of southwestern Sri Lanka was heavily damaged. A reduction of 20-30% is expected for the output of low-grown tea in the next three months.

These record extreme events (high temperatures, low temperatures and high rainfall amounts and droughts) all go into calculating the monthly and annual averages which, for temperatures, have been gradually increasing over the past 100 years. New record extreme events occur every year somewhere in the globe, but in recent years the number of such extremes have been increasing. According to recent climate change scientific assessment reports of the joint WMO/UNEP Intergovernmental Panel on Climate Change (IPCC), the global average surface temperature has increased since 1861. Over the 20th century the increase has been around 0.6°C. This value is about 0.15°C larger than that estimated by the previous reports. New analyses of proxy data for the Northern Hemisphere indicate that the increase in temperature in the 20th century is likely to have been the largest in any century during the past 1000 years. It is also likely that, in the Northern Hemisphere, the 1990s were the warmest decade and 1998 the warmest year. While the trend towards warmer globally averaged surface temperatures has been uneven over the course of the last century, the trend for the period since 1976 is roughly three times that for the past 100 years as a whole. Global average land and sea surface temperatures in May 2003 were the second highest since records began in 1880. Considering land temperatures only, last May was the warmest on record.

The influence of El Niño and La Niña on these extreme events is in general undefined. The World Meteorological Organization (WMO) and its Members, the National Meteorological and Hydrological Services along with various research institutes, will continue to organize research and document the influence of El Niño and other large scale climate phenomena on climate extreme events.


For more information please contact:

Ms Carine Richard-Van Maele

Chief, Information and Public Affairs

World Meteorological Organization

Tel: +41 (0) 22 730 83 14/5

Fax:+41 (0) 22 730 80 27

E-mail: ipa@gateway.wmo.ch

Internet website: http://www.wmo.ch


7 July 2003

AGU Release No. 03-19

For Immediate Release

Contact: Harvey Leifert

+1 (202) 777-7507


Leading Climate Scientists Reaffirm View That Late 20th Century Warming Was Unusual and

Resulted From Human Activity

WASHINGTON - A group of leading climate scientists has reaffirmed the "robust consensus view" emerging from the peer reviewed literature that the warmth experienced on at least a hemispheric scale in the late 20th century was an anomaly in the previous millennium and that human activity likely played an important role in causing it. In so doing, they refuted recent claims that the warmth of recent decades was not unprecedented in the context of the past thousand years.

Writing in the 8 July issue of the American Geophysical Union publication Eos, Michael Mann of the University of Virginia and 12 colleagues in the United States and United Kingdom endorse the position on climate change and greenhouse gases taken by AGU in 1998. Specifically, they say that "there is a compelling basis for concern over future climate changes, including increases in global-mean surface temperatures, due to increased concentrations of greenhouse gases, primarily from fossil-fuel burning."

The Eos article is a response to two recent and nearly identical papers by Drs. Willie Soon and Sallie Baliunas of the Harvard-Smithsonian Center for Astrophysics, published in

Climate Research and Energy & Environment (the latter paper with additional co-authors). These authors challenge the generally accepted view that natural factors cannot fully explain recent warming and must have been supplemented by significant human activity, and their papers have received attention in the media and in the U.S. Senate. Requests from reporters to top scientists in the field, seeking comment on the Soon and Baliunas position, lead to memoranda that were later expanded into the current Eos article,

which was itself peer reviewed.

Paleoclimatologists (scientists who study ancient climates) generally rely on instrumental data for the past 150 years and "proxy" indicators, such as tree rings, ice cores, corals, and lake sediments to reconstruct the climate of earlier times. Most of the available data pertain to the northern hemisphere and show, according to the authors, that the warmth of the northern hemisphere over the past few decades is likely unprecedented in the last 1,000 years and quite possibly in the preceding 1,000 years as well.

Climate model simulations cannot explain the anomalous late 20th century warmth without taking into account the contributions of human activities, the authors say. They make three major points regarding Soon and Baliunas's recent assertions challenging these


First, in using proxy records to draw inferences about past climate, it is essential to assess their actual sensitivity to temperature variability. In particular, the authors say, Soon and Baliunas misuse proxy data reflective of changes in moisture or drought, rather than temperature, in their analysis.

Second, it is essential to distinguish between regional temperature anomalies and hemispheric mean temperature, which must represent an average of estimates over a sufficiently large number of distinct regions. For example, Mann and his co- authors say, the concepts of a "Little Ice Age" and "Medieval Warm Period" arose from the Eurocentric origins of historic climatology. The specific periods of coldness and warmth differed from region to region and as compared with data for the northern hemisphere as a whole.

Third, according to Mann and his colleagues, it is essential to define carefully the modern base period with which past climate is to be compared and to identify and quantify uncertainties. For example, they say, the most recent report of the Intergovernmental

Panel on Climate Change (IPCC) carefully compares data for recent decades with reconstructions of past temperatures, taking into account the uncertainties in those reconstructions. IPCC concluded that late 20th century warmth in the northern hemisphere likely exceeded that of any time in the past millennium. The method used by Soon and Baliunas, they say, considers mean conditions for the entire 20th century as the base period and determines past temperatures from proxy evidence not capable of resolving trends on a decadal basis. It is therefore, they say, of limited value in determining whether recent warming in anomalous in a long term and large scale context.

The Eos article started as a memorandum that Michael Oppenheimer and Mann drafted to help inform colleagues who were being contacted by members of the media regarding the Soon and Baliunas papers and wanted an opinion from climate scientists and paleoclimatologists who were directly familiar with the underlying issues.

Mann and Oppenheimer learned that a number of other colleagues, including Tom Wigley of the University Corporation for Atmospheric Research (UCAR) in Boulder, Colorado; Philip Jones of the University of East Anglia's Climatic Research Unit in Norwich, United Kingdom; and Raymond Bradley of the University of Massachusetts in Amherst were receiving similar media requests for their opinions on the matter. Their original memorandum evolved into a more general position paper jointly authored by a larger group of leading scientists in the field.

Mann says he sees the resulting Eos article as representing an even broader consensus of the viewpoint of the mainstream climate research community on the question of late 20th century warming and its causes. The goal of the authors, he says, is to reaffirm support for the AGU position statement on climate change and greenhouse gases and clarify what is currently known from the paleoclimate record of the past one-to-two thousand years and, in particular, what the bearing of this evidence is on the issue of the detection of human influence on recent climate change.


Notes for Journalists:

The article, "On Past Temperatures and Anomalous Late-20th

Century Warmth," appears in Eos, Volume 84, No. 27, 8 July

2003, page 256.

Authors (full list):

Michael Mann, University of Virginia, Charlottesville, Virginia; Caspar Ammann and Kevin Trenberth, National Center for Atmospheric Research, Boulder, Colorado; Raymond Bradley, University of Massachusetts, Amherst, Massachusetts; Keith Briffa, Philip Jones, and Tim Osborn, Climatic Research Unit, University of East Anglia, Norwich, United Kingdom; Tom Crowley, Nicholas School of the Environment and Earth Science, Duke University, Durham, North Carolina; Malcolm Hughes, Laboratory of Tree-Ring Research, University of Arizona, Tucson, Arizona; Michael Oppenheimer, Princeton University, Princeton, New Jersey; Jonathan Overpeck, Department of Geosciences and Institute for the Study of Planet Earth, University of Arizona, Tucson, Arizona; Scott Rutherford, University of Rhode Island, Narragansett, Rhode Island; Tom Wigley, University Corporation for Atmospheric Research and National Center for Atmospheric Research, Boulder, Colorado.

AGU's position statement, Climate Change and Greenhouse Gases (1998), may be read at


A peer reviewed article, discussing the scientific background to the position statement, appeared in Eos, Volume 80, No 39, September 28, 1999, page 453, and may be read at