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Fifth National Climate Assessment - Read the Report

Overview: Fourth National Climate Assessment Volume II: Impacts, Risks, and Adaptation in the United States

The Overview is a summary of the findings of NCA4 Vol. II, as presented in Chapter 1 of the full report. Volume II of the Fourth National Climate Assessment focuses on the human welfare, societal, and environmental elements of climate change and variability for 10 regions and 18 national topics, with particular attention paid to observed and projected risks, impacts, consideration of risk reduction, and implications under different mitigation pathways. Where possible, NCA4 Vol. II provides examples of actions underway in communities across the United States to reduce the risks associated with climate change, increase resilience, and improve livelihoods.This assessment was written to help inform decision-makers, utility and resource managers, public health officials, emergency planners, and other stakeholders who are interested in better understanding the effects of climate change on the United States.