Fourth National Climate Assessment Vol I + II
NCA4 Vol II: Impacts, Risks, and Adaptation in the United States
NCA4 Vol I: Climate Science Special Report
The Reports Library features scientific assessments, annual reports, strategic research plans, and other resources produced by USGCRP and the collaborative efforts of our member agencies. Select reports by other authoritative scientific bodies with whom we work, such as the Intergovernmental Panel on Climate Change (IPCC) and the National Research Council (NRC), are also accessible here. Most reports are available for download (open and click View); some can be ordered in print free of charge (open and click Add to Cart).
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The Synthesis Report synthesizes the main findings of the IPCC's Fifth Assessment Report, based on contributions from Working Group I (The Physical Science Basis), Working Group II (Impacts, Adaptation and Vulnerability), and Working Group III (Mitigation of Climate Change), plus two additional IPCC reports.
This report synthesizes the contributions of Working Groups I, II, and III to the IPCC’s Fourth Assessment Report, and also draws on recent IPCC Special Reports. It draws together policy-relevant scientific, technical, and socioeconomic information related to climate change, with the goal of assisting governments and other decision makers in formulating and implementing responses.
The Working Group I contribution to the IPCC’s Fifth Assessment Report (WGI AR5) provides a comprehensive assessment of the physical science basis of climate change.
This Special Report of the IPCC Working Groups I and II explores the social as well as physical dimensions of weather- and climate-related disasters, considering opportunities for managing risks at local to international scales.