Intergovernmental Panel on Climate Change Third Assessment Report

Intergovernmental Panel on Climate Change Third Assessment Report
Name	Third Assessment Report
Date	2001
Publisher	Intergovernmental Panel on Climate Change
Subject	Climate change science and impacts

Intergovernmental Panel on Climate Change Third Assessment Report

The Third Assessment Report was a major scientific appraisal completed in 2001 by the Intergovernmental Panel on Climate Change, synthesizing evidence on climate system change, impacts, and response options. It informed deliberations in forums such as the United Nations Framework Convention on Climate Change, the Kyoto Protocol processes, and national policy debates involving institutions like the European Commission and the United States Congress. The report's assessment chapters drew on work by scientists affiliated with universities and agencies including the Hadley Centre, NASA, NOAA, and the Max Planck Institute.

Background and Preparation

The report was prepared under the leadership of the Intergovernmental Panel on Climate Change secretariat in collaboration with authors from institutions such as the Met Office, Columbia University, MIT, Princeton University, and the Potsdam Institute. Review cycles involved governments including United States and Japan and organizations such as the World Meteorological Organization and the United Nations Environment Programme. Lead authors and review editors from universities like University of Oxford and Stanford University coordinated inputs from modelers at centers including the Hadley Centre and Centre National de Recherches Météorologiques, while policymakers from the European Union and the World Bank observed release processes. The preparation built on earlier assessments authored during periods marked by events like the 1997 Kyoto Protocol negotiations and the 1998 El Niño.

Key Findings and Conclusions

The assessment concluded that warming of the climate system was evident from observations at sites including Mauna Loa Observatory and datasets produced by NASA and NOAA, and that most of the observed increase in global average temperatures since the mid-20th century was very likely due to anthropogenic greenhouse gas concentrations from activities in regions such as China and India. It summarized projections from climate models developed at centers like the Hadley Centre, GISS and the Max Planck Institute showing continued warming under scenarios used by the Intergovernmental Panel on Climate Change that referenced socioeconomic pathways relevant to policy fora such as the G8. The report linked projected impacts to sectors regulated in forums including the World Trade Organization and to infrastructure in cities such as New York City, Mumbai, and Shanghai.

Methodology and Assessment Process

Authors employed detection and attribution methods developed at institutions including Lawrence Livermore National Laboratory and Scripps Institution of Oceanography, using climate models from groups such as Hadley Centre and GFDL and paleoclimate reconstructions from teams at University of Arizona and University of Bern. The assessment synthesized peer-reviewed literature published in journals like Nature, Science, and Journal of Climate after coordinated author meetings held in locations including Geneva and Tokyo. Review procedures allowed comments from governments including Canada and Australia and expert reviewers from bodies such as the Royal Society and the National Academy of Sciences (United States), with final approval by representatives from ministries in countries such as France and Germany.

Impacts and Regional Assessments

Regional chapters incorporated studies of vulnerabilities and adaptation options for regions such as Europe, Africa, Latin America, Asia, and island states including Kiribati and Maldives. Impacts on sectors were described drawing on analyses from organizations like the Food and Agriculture Organization, the International Monetary Fund, and the World Health Organization, including effects on agriculture in the Sahel, glacier retreat in the Himalayas, and sea level rise affecting delta regions such as the Ganges Delta and port cities like Rotterdam and Bangkok. The report integrated findings on ecosystems from teams at Smithsonian Institution and the Woods Hole Oceanographic Institution and on hydrology from the US Geological Survey.

Policy Implications and Responses

The report provided scientific input relevant to negotiations under the United Nations Framework Convention on Climate Change and to instruments such as the Kyoto Protocol and informed policy deliberations in parliaments including the United Kingdom Parliament and the United States Congress. It evaluated mitigation options involving energy technologies promoted by groups such as the International Energy Agency and the potential role of afforestation projects overseen by agencies like the United Nations Development Programme. Cost estimates and policy instruments were compared with analysis from bodies including the World Bank and think tanks such as the Brookings Institution.

Reception and Criticism

Governments including the United States and Russia and scientific bodies such as the American Meteorological Society and the Royal Society reacted to the report, while critiques emerged from commentators associated with institutions like the Competitive Enterprise Institute and some authors in media outlets such as The Wall Street Journal and The Times (London). Debates concerned interpretation of detection and attribution results, uncertainties highlighted by researchers at Lawrence Berkeley National Laboratory and skeptics associated with universities including Penn State University and discussions in policy forums such as the G77. Subsequent exchanges involved clarifications by IPCC authors and responses by academies including the Australian Academy of Science.

Legacy and Influence on Subsequent Assessments

The Third Assessment Report influenced the structure and scope of later assessments including the Fourth Assessment Report and the Sixth Assessment Report, and it informed the work of agencies such as the European Environment Agency, Inter-American Development Bank, and national programs at institutions like CSIRO and NOAA. Its synthesis contributed to subsequent scientific syntheses cited by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services and to negotiations culminating in agreements referenced in forums such as the Conference of the Parties (UNFCCC). The report remains a landmark in bridging research communities at universities including Harvard University and University of California, Berkeley with policymakers in capitals such as Washington, D.C. and Beijing.

Category:Intergovernmental Panel on Climate Change reports