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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AMAP, 2019. Arctic Ocean Acidification Assessment 2018: Summary for Policy-Makers
This assessment report presents the results of the 2018 Arctic Monitoring and Assessment Programme (AMAP) assessment of Arctic Ocean Acidification. This is the second such assessment dealing with ocean acidification from an Arctic-wide perspective , and complements several assessments that AMAP has delivered over past years concerning the effects of climate change on Arctic ecosystems and people.
These State Climate Summaries were produced to meet a demand for state-level information in the wake of the Third U.S. National Climate Assessment, released in 2014. The summaries cover assessment topics directly related to NOAA’s mission, specifically historical climate variations and trends, future climate model projections of climate conditions during the 21st century, and past and future conditions of sea...
This Overview Report presents a summary of the first comprehensive assessment of Arctic Ocean Acidification conducted by the Arctic Monitoring and Assessment Programme (AMAP).
Ocean acidification is occurring at a rapid and accelerating pace, and the Arctic Ocean is on the frontline of this global change. AMAP’s 2013 assessment of Arctic Ocean acidification provides the first Arctic-wide perspective on today’s progressively increasing seawater acidity.
The 2009 Arctic Marine Shipping Assessment (AMSA) called for the Arctic States to identify areas of heightened ecological and cultural significance in light of changing climate conditions and increasing multiple marine uses. This report identifies those areas.
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.
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.
US CLIVAR is a national research program investigating the variability and predictability of the global climate system on time scales ranging from seasons to hundreds of years, with a particular emphasis on the role of the ocean.
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.