Intergovernmental Panel on Climate Change (IPCC)

The Intergovernmental Panel on Climate Change (IPCC) was established in 1988 as a joint project of the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO). The primary mission of the IPCC is to bring together the world's leading experts on the earth's climate to gather, assess, and disseminate scientific information about climate change, with a view to informing international and national policy makers. The IPCC has become the highest-profile and best-regarded international agency concerned with the climatic consequences of "greenhouse gases," such as carbon dioxide and methane , that are a byproduct of the combustion of fossil fuels . The IPCC is an organization that has been and continues to be at the center of a great deal of controversy.

The IPCC was established partly in response to Nobel Laureate Mario Molina's 1985 documentation of chemical processes which occur when human-made chemicals deplete the earth's atmospheric ozone shield. Ozone depletion is likely to result in increased levels of ultraviolet radiation reaching the earth's surface, producing a host of health, agricultural, and environmental problems. Molina's work helped to persuade most of the industrialized nations to ban chlorofluorocarbons and several other ozone-depleting chemicals. It also established a context in which national and international authorities began to pay serious attention to the global environmental consequences of atmospheric changes resulting from industrialization and reliance on fossil fuels.

Continuing to operate under the auspices of the United Nations and headquartered in Geneva, Switzerland, the IPCC is organized into three working groups and a task force, and meets about once a year. The first group gathers scientific data and analyzes the functioning of the climate system with special attention to the detection of potential changes resulting from human activity. The second group's assignment is to assess the potential socioeconomic impacts and vulnerabilities associated with climate change. It is also charged with exploring options for humans to adapt to potential climate change. The third group focuses on ways to reduce greenhouse gas emissions and to stop or reduce climate change. The task force is charged with maintaining inventories of greenhouse emissions for all countries.

The IPCC has published its major findings in "Full Assessment" Reports, first issued in 1990 and 1995. The Tenth Session of the IPCC (Nairobi, 1994) directed that future full assessments should be prepared approximately every five years. The Third Assessment Report was entitled "Climate Change 2001". Special reports and technical papers are also published as the panel identifies issues.

The IPCC has drawn a great deal of criticism virtually from its inception. Massive amounts of money are at stake in policy decisions which might seek to limit greenhouse gas emissions, and much of the criticism directed at the IPCC tends to come from lobbying and research groups mostly funded by industries that either produce or use large quantities of fossil fuels. Thus, a lobbying group sponsored by energy, transportation , and manufacturing interests called the Global Climate Coalition attacked parts of the 1995 report as unscientific. At the core of the controversy was Chapter Eight of the report, "Detection of Climate Change and Attribution of Causes". Although the IPCC was careful to hedge its conclusions in various ways, acknowledging difficulties in measurement, disagreements over methodologies for interpreting data, and general uncertainty about the conclusions of its findings, it nevertheless suggested a connection between greenhouse gas emissions and global warming. Not satisfied with such caveats, the Global Climate Coalition charged that the IPCC's conclusions had been presented as far less debatable than they actually were. This cast a cloud of uncertainty over the report, at least for some United States policymakers. However, other leaders took the report more seriously. The Second Assessment Report provided important input to the negotiations that led to the development of the Kyoto Protocol in 1997, a treaty aimed at reducing the global output of greenhouse gases .

In the summer of 1996, results of new studies of the upper atmosphere were published which provided a great deal of indirect support for the IPCC's conclusions. Investigators found significant evidence of cooling in the upper atmosphere and warming in the lower atmosphere, with this effect being especially pronounced in the southern hemisphere. These findings confirmed the predictions of global warming models such as those employed by the IPCC.

Perhaps emboldened by this confirmation, but still facing a great deal of political opposition, the IPCC released an unequivocal statement about global warming and its causes in November 1996. The IPCC declared that "the balance of evidence suggests that there is a discernible human influence on global climate". The statement made clear that a preponderance of evidence and a majority of scientific experts indicated that observable climate change was a result of human activity. The IPCC urged that all nations limit their use of fossil fuels and develop more energy-efficient technologies.

These conclusions and recommendations provoked considerable criticism from less-developed countries. Leaders of the less-industrialized areas of the world tend to view potential restrictions on the use of fossil fuels as unfair hindrance of their efforts to catch up with the United States and Western Europe in industry, transportation, economic infrastructure, and standards of living. The industrialized nations, they point out, were allowed to develop without any such restrictions and now account for the vast majority of the world's energy consumption and greenhouse gas emissions. These industrialized nations therefore should bear the brunt of any efforts to protect the global climate, substantially exempting the developing world from restrictions on the use of fossil fuels.

The IPCC's conclusions and recommendations have also drawn strong opposition from industry groups in the United States, such as the American Petroleum Institute, and conservative Republican politicians. These critics charge that the IPCC's new evidence is only fashionable but warmed-over theory, and that no one has yet proven conclusively that climate change is indeed related to human influence. In view of the likely massive economic impact of any aggressive program aimed at the reduction of emissions, there is no warrant for following the IPCC's dangerous and ill-considered advice. Under Republican leadership, Congress slashed funds for Environmental Protection Agency and Department of Energy programs concerned with global warming and its causes, as well as funds for researching alternative and cleaner sources of energy.

These funding cuts and the signals they sent created foreign relations problems for the Clinton Administration. The United States was unable to honor former President Bush's 1992 pledge (at the Rio de Janeiro Earth Summit) to reduce the country's emission of carbon dioxide and methane to 1990 levels by the year 2000. Indeed, owing in part to low oil prices and a strong domestic economy, the United States was consuming more energy and emitting more greenhouse gases than ever before by 2000.

In the summer of 2001, the IPCC released its strongest statement to date on the problem of global warming, in its Third Assessment Report. The report, "Climate Change 2001", provides further evidence for global warming and its cause—the widescale burning of fossil fuels by humans. The report projects that global mean surface temperatures on earth will increase by 2.5–10.4°F (1.5–5.9°C) by the year 2100, unless greenhouse gas emissions are reduced well below current levels. The report also notes that this warming trend will represent the fasting warming of the earth in 10,000 years, with possible dire consequences to human society and the environment .

In the early 2000s, the administration of President George W. Bush, a former oilman, was resistant to the ideas of global warming and reducing greenhouse gas emissions. The administration strongly opposed the Kyoto Treaty and domestic pollution reduction laws, claiming such measures would cost jobs and reduce the standard of living, and that the scientific evidence was inconclusive. In June 2001, a National Academy of Science (NAS) panel reported to President Bush that the IPCC's studies on global warming were scientifically valid. In April 2002, with pressure from the oil industry, the Bush administration forced the removal of IPCC Chairman Robert Watson, an American atmospheric scientist who had been outspoken over the issue of climate change and the need for greenhouse gas reduction in industrialized countries.

The IPCC elected Dr. Rajendra K. Pachauri as its next Chairman at its nineteenth session in Geneva. Dr. Pachauri, a citizen of India, is a well-known world-class expert in economics and technology, with a strong commitment to the IPCC process and to scientific integrity.

[Lawrence J. Biskowski and Douglas Dupler ]

RESOURCES

BOOKS

McKibbin, Warwick J., and Peter Wilcoxen. Climate Change Policy After Kyoto: Blueprint for a Realistic Approach. Washington DC: The Brookings Institution Press, 2002.

PERIODICALS

McKibben, Bill. "Climate Change 2001: Third Assessment Report." New York Review of Books, July 5, 2001, 35.

Trenberth, Kevin E. "Stronger Evidence of Human Influences on Climate: The 2001 IPCC Assessment." Environment, May 2001, 8.

OTHER

Intergovernmental Panel on Climate Change Home Page. [cited July 2002]. <http://www.ipcc.ch>.

Union of Concerned Scientists Global Warming Web Page. [cited July 2002]. <http://www.ucsusa/warming>.

World Meteorological Organization Home Page. [cited July 2002]. <http://www.wmo.ch>.

ORGANIZATIONS

IPCC Secretariat, C/O World Meteorological Organization, 7bis Avenue de la Paix, C.P. 2300, CH-1211, Geneva, Switzerland 41-22-730-8208, Fax: 41-22-730-8025, Email: ipcc.sec@gateway.wmo.ch, <http://www.ipcc.ch>

Intergovernmental Panel on Climate Change (IPCC)

Introduction

The Intergovernmental Panel on Climate Change (IPCC) is a scientific panel or committee established in 1988 by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO), both arms of the United Nations (UN). The purpose of the IPCC is to pool, evaluate, and summarize the state of scientific knowledge about all aspects of climate change, especially human-caused climate change, and to evaluate policies related to climate change. Experts from more than 130 countries were participating in the IPCC in late 2007. The IPCC does not conduct original research, but is a forum in which the consensus view of the world's climate and meteorology communities can be hammered out. Its reports have been influential in the formation of world opinion about the reality and causes of climate change.

Historical Background and Scientific Foundations

The theory that Earth is kept warm by the heat-capturing effect of carbon dioxide and other gases was first proposed by Swedish chemist Svante Arrhenius (1859-1927) in 1896. Starting in the 1950s, some scientists, notably Canadian physicist Gilbert Plass (1921-2004), began to propose that human-caused increases in greenhouse gas concentrations, especially of carbon dioxide

and methane, might cause the world's climate to warm. In 1979, the World Meteorological Organization (WMO), the United Nations' organization for the study of weather and other aspects of earth science, organized a World Climate Conference, the first of its kind. Scientists at the conference agreed that possible human-caused climate warming was a concern.

In 1985, a UN scientific conference in Austria also concluded that significant human-caused global warming might be occurring or occur in the future. The tenth congress of the WMO recommended an international, scientific assessment of climate change. The new group, the IPCC, was authorized by the Executive Council of the WMO and the Governing Council of the UNEP in 1988. Its facilities are in Geneva, Switzerland.

The work of the IPCC is primarily to prepare reports on climate issues after sifting and debating scientific evidence from peer-reviewed scientific sources. A peer-reviewed source is an article or book that is subjected to criticism by some of the author's fellow scientists (that is, his or her peers or equals) before publication. Peer review is the scientific community's method of screening out faulty work.

Experts are appointed to the IPCC by each participating government. Such scientists work as volunteers. IPCC reports are prepared following a complex process in which authors prepare a draft that is peer-reviewed, revised, reviewed by experts and the participating governments, and revised again to produce a final draft that is again reviewed by participating governments. The IPCC's reports are some of the most intensively peer-reviewed summaries of scientific knowledge ever produced.

Impacts and Issues

The IPCC has produced special reports on the storage of carbon dioxide, the ozone layer, and other climate topics. Its most influential products have been its four Assessment Reports on global climate change in 1990, 1995, 2001, and 2007. Responsibility for each of these reports was divided among three Working Groups. The first group reported on the scientific basis of climate-change knowledge. This included weather observations from surface and satellite sources; paleoclimate data from ice cores, ocean-sediment cores, and other sources; observations of changes in ecosystems such as forests; and the results of computer calculations. The second Working Group reported on the impacts of climate change on agriculture, forestry, ecosystems, water resources, human settlements, and oceans. The third reported on possible adaptation and vulnerability to climate change. All three sub-reports emphasized areas of uncertainty and ignorance.

The IPCC's Fourth Assessment Reports, titled Climate Change 2007, were released in 2007. New data were available to the scientists drafting this report, including more information about ancient climate and a widened range of carefully tested computer models. The scientific uncertainties of earlier years were reduced. As of 2007, the IPCC stated that “warming of the climate system is unequivocal” and that “most of (>50% of) the observed increase in globally averaged temperatures since the mid-20th century is very likely (confidence level >90%) due to the observed increase in anthropogenic (human) greenhouse gas concentrations.”

The IPCC's 2007 report has been both praised and criticized. Among the critics are those who doubt greenhouse warming and argue that global warming is either not real or is merely a natural process, not human-caused. Many of these critics are not scientists, or are not experts in climate or weather science, though a few are qualified scientists. The great majority of climate and weather scientists agreed, as of 2007, that the IPCC's conclusions were valid.

In turn, the 2007 IPCC report has also been criticized for being too conservative in discussing climate change and its effects. Possible reasons for IPCC over-optimism include the report's exclusion of data collected after the end of 2005 (data collected since that time show faster melting of ice in Greenland and part of Antarctica). Another possible reason is the influence over the IPCC report-preparation process by governments such as those of the United States, China, and Saudi Arabia, which have so far refused to agree to binding changes in their industrial, agricultural, and other climate-related practices.

WORDS TO KNOW

ANTHROPOGENIC: Made by people or resulting from human activities. Usually used in the context of emissions that are produced as a result of human activities.

GREENHOUSE GASES: Gases that cause Earth to retain more thermal energy by absorbing infrared light emitted by Earth's surface. The most important greenhouse gases are water vapor, carbon dioxide, methane, nitrous oxide, and various artificial chemicals such as chlorofluorocarbons. All but the latter are naturally occurring, but human activity over the last several centuries has significantly increased the amounts of carbon dioxide, methane, and nitrous oxide in Earth's atmosphere, causing global warming and global climate change.

ICE CORE: A cylindrical section of ice removed from a glacier or an ice sheet in order to study climate patterns of the past. By performing chemical analyses on the air trapped in the ice, scientists can estimate the percentage of carbon dioxide and other trace gases in the atmosphere at that time.

PALEOCLIMATE: The climate of a given period of time in the geologic past.

PEER REVIEW: The standard process in science for reducing the chances that faulty or fraudulent claims will be published in scientific journals. Before publication of an article, scientists with expertise in the article's subject area review the manuscript, usually anonymously, and make criticisms that may lead to revision or rejection of the article.

In 2007, the work of the IPCC, along with that of former U.S. Vice President Al Gore, was acknowledged with the Nobel Peace Prize. According to the Nobel Committee, they were chosen “[f]or their efforts to build up and disseminate greater knowledge about man-made climate change, and to lay the foundations for the measures that are needed to counteract such change.” Following the announcement, some wondered why the IPCC and Gore had won the “peace” prize, rather than one in the sciences. In a press release, the Nobel committee explained its selection, noting that it is “highlighting the link …between the risk of accelerating climate change and the risk of violent conflict and wars.” The committee observed that climate change could impact living conditions throughout the world, leading various peoples to migrate to less impacted areas. As Earth's resources become more limited, violence and conflict would likely result.

See Also Climate Change Skeptics; IPCC Climate Change 2007 Report; IPCC Climate Change 2007 Report: Criticism; IPCC Climate Change 2007 Report: Impacts, Adaptation and Vulnerability; IPCC Climate Change 2007 Report: Mitigation of Climate Change; IPCC Climate Change 2007 Report: Physical Science Basis.

BIBLIOGRAPHY

Books

Committee on the Science of Climate Change, National Academy of Sciences. Climate Change Science: An Analysis of Some Key Questions. Washington, DC: National Academies Press, 2001.

Metz, B., et al, eds. Climate Change 2007: Mitigation of Climate Change: Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. New York: Cambridge University Press, 2007.

Parry, M. L., et al, eds. Climate Change 2007: Impacts, Adaptation and Vulnerability: Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. New York: Cambridge University Press, 2007.

Solomon, S., et al, eds. Climate Change 2007: The Physical Science Basis: Contribution of Working Group I to the Fourth Assessment Report of theIntergovernmental Panel on Climate Change. New York: Cambridge University Press, 2007.

Web Sites

“16 Years of Scientific Assessment in Support of the Climate Convention.” Intergovernmental Panel on Climate Change (IPCC), December 2004. <http://www.ipcc.ch/about/anniversarybrochure.pdf> (accessed October 9, 2007).

“The Nobel Peace Prize 2007.” Nobel Foundation, October 2007. <http://nobelprize.org/nobel_prizes/peace/laureates/2007/> (accessed November 12, 2007).

Larry Gilman

Intergovernmental Panel on Climate Change

Introduction

The Intergovernmental Panel on Climate Change (IPCC) is a scientific committee established in 1988 by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO), both arms of the United Nations. The purpose of the IPCC is to pool, evaluate, and summarize the current state of scientific knowledge about all aspects of climate change, especially human-caused climate change, and to evaluate policies related to climate change. Experts from more than 130 countries were participating in the IPCC as of 2008. The IPCC does not conduct original research, but is a forum in which the consensus view of the world’s climate and meteorology communities can be forged in open debate. Its reports have been influential in the formation of world public opinion about the reality and causes of climate change.

Historical Background and Scientific Foundations

The theory that Earth is kept warm by the heat-capturing effect of carbon dioxide and other gases was first proposed by Swedish chemist Svante Arrhenius (1859–1927) in 1896. Starting in the 1950s, some scientists, notably Canadian physicist Gilbert Plass (1921–2004), began to propose that human-caused increases in greenhouse-gas concentrations, especially of carbon dioxide and methane, might cause the world’s climate to warm. In 1979, the WMO, the United Nations’ organization for the study of weather and other aspects of earth science, organized a World Climate Conference, the first of its kind. Scientists at the conference agreed that possible human-caused climate warming was a concern.

In 1985, a United Nations scientific conference in Austria also concluded that significant human-caused global warming might be occurring or occur in the future. The tenth congress of the WMO recommended an international, scientific assessment of climate change. The new group, the IPCC, was authorized by the Executive Council of the WMO and the Governing Council of the UNEP in 1988. Its facilities are in Geneva, Switzerland.

The work of the IPCC is primarily to prepare reports on climate issues after sifting and debating scientific evidence from peer-reviewed scientific sources. A peer-reviewed source is an article or book that is subjected to criticism by some of the author’s fellow scientists (that is, his or her peers or equals) before publication. Peer review is the scientific community’s method of screening out faulty work.

Experts are appointed to the IPCC by each participating government. Such scientists work as volunteers. IPCC reports are prepared following a complex process in which authors prepare a draft that is peer-reviewed, revised, reviewed by experts and the participating governments, and revised again to produce a final draft that is again reviewed by participating governments. The IPCC’s reports are some of the most intensively peer-reviewed summaries of scientific knowledge ever produced.

Impacts and Issues

The IPCC has produced special reports on the storage of carbon dioxide, the ozone layer, and other climate topics. Its most influential products have been its four Assessment Reports on global climate change in 1990, 1995, 2001, and 2007. Responsibility for each of these reports was divided among three working groups. The first group reported on the physical scientific basis of climate-change knowledge. This included weather observations from surface and satellite sources; paleoclimate data from ice cores, ocean-sediment cores, and other sources; observations of changes in ecosystems such as forests; and the results of computer calculations. The second working group reported on the impacts of climate change on agriculture, forestry, ecosystems, water resources, human settlements, and oceans. The third reported on possible adaptation and vulnerability to climate change. All three sub-reports emphasized areas of uncertainty and ignorance.

The IPCC’s fourth Assessment Reports, titled Climate Change 2007, were released in 2007. New data were available to the scientists drafting this report, including more information about ancient climate and a widened range of carefully tested computer models. The scientific uncertainties of earlier years were reduced. In its 2007 report, the IPCC stated that “warming of the climate system is unequivocal” and that “most (&gt;50%) of the observed increase in globally averaged temperatures since the mid-20th century is very likely (confidence level &gt;90%) due to the observed increase in anthropogenic (human-caused) greenhouse-gas concentrations.”

The IPCC’s 2007 report has been both praised and criticized. Among the critics are those who doubt greenhouse warming and argue that global warming is either not real or is merely a natural process, not human-caused. Many of these critics are not scientists, or are not experts in climate or weather science, though a few are qualified scientists. The great majority of climate and weather scientists agreed, as of 2007, that the IPCC’s basic conclusions were valid.

On the other hand, the 2007 IPCC report has also been criticized for being too conservative in discussing climate change and its effects. Possible reasons for IPCC over-optimism include the report’s exclusion of data collected after the end of 2005 (data collected since that time show faster melting of ice in Greenland and part of Antarctica). Another possible reason is the influence over the IPCC report-preparation process by governments—such as those of the United States, China, and Saudi Arabia—which have so far refused to agree to binding changes in their industrial, agricultural, and other climate-related practices.

In 2007, the work of the IPCC, along with that of former U.S. Vice President Al Gore, was acknowledged with the Nobel Peace Prize. According to the Nobel Committee, they were chosen "for their efforts to build up and disseminate greater knowledge about man-made climate change, and to lay the foundations for the measures that are needed to counteract such change.” Following the announcement, some wondered why the IPCC and Gore had won the “peace” prize, rather than one in the sciences. In a press release, the Nobel committee explained its selection, noting that in awarding the

WORDS TO KNOW

ANTHROPOGENIC: Made by humans or resulting from human activities.

GREENHOUSE GAS: A gas whose accumulation in the atmosphere increases heat retention.

ICE CORE: A cylindrical section of ice removed from a glacier or ice sheet in order to study climate patterns of the past.

PALEOCLIMATE: The climate of a given period of time in the geologic past.

PEER REVIEW: The standard process in science for reducing the chances that faulty or fraudulent claims will be published in scientific journals. Before publication of an article, scientists with expertise in the article’s subject area review the manuscript, usually anonymously, and make criticisms that may lead to revision or rejection of the article.

prize as it did, it was “highlighting the link… between the risk of accelerating climate change and the risk of violent conflict and wars.” The committee observed that climate change could impact living conditions throughout the world, leading various peoples to migrate to less-impacted areas. As Earth’s resources become more limited, increased violence and conflict may result.

See Also Climate Change; Global Warming; IPCC 2007 Report

BIBLIOGRAPHY

Books

Committee on the Science of Climate Change, National Academy of Sciences. Climate Change Science: An Analysis of Some Key Questions. Washington, DC: National Academies Press, 2001.

Metz, B., et al, eds. Climate Change 2007: Mitigation of Climate Change: Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. New York: Cambridge University Press, 2007.

Parry, M. L., et al, eds. Climate Change 2007: Impacts, Adaptation and Vulnerability: Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. New York: Cambridge University Press, 2007.

Solomon, S., et al, eds. Climate Change 2007: The Physical Science Basis: Contribution of Working Group I to the Fourth Assessment Report of the

Intergovernmental Panel on Climate Change. New York: Cambridge University Press, 2007.

Web Sites

Intergovernmental Panel on Climate Change (IPCC). “16 Years of Scientific Assessment in Support of the Climate Convention.” December 2004. http://www.ipcc.ch/pdf/10th-anniversary/anniversary-brochure.pdf (accessed March 25, 2008).

Nobel Foundation. “The Nobel Peace Prize 2007.” October 2007. http://nobelprize.org/nobel_prizes/peace/laureates/2007/ (accessed March 25, 2008).

Larry Gilman

IN CONTEXT: FRANK AND STARK WARNINGS

“Continued greenhouse-gas emissions at or above current rates would cause further warming and induce many changes in the global climate system during the 21st century that would very likely be larger than those observed during the 20th century.”

…“It is very likely that hot extremes, heat waves and heavy precipitation events will continue to become more frequent.”

SOURCE: Solomon, S., et al, eds. “IPCC, 2007: Summary for Policymakers.” In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. New York: Cambridge University Press, 2007.