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 Working Group I contribution to the IPCC Fifth Assessment Report (WGI AR5) provides a comprehensive assessment of the physical science basis of climate change. Here, the Working Group I report is summarized for both technical and policy audiences.