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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This report provides an overview of the scientific consensus on the current and future climate changes of particular relevance to U.S. transportation, including the limits of present scientific understanding as to their precise timing, magnitude, and geographic location; identifies potential impacts on U.S. transportation and adaptation options; and offers recommendations for both research and actions that can be taken to prepare for climate change.
An ad hoc committee, composed of individuals who have studied, participated in, or been users of global change assessments, was convened to prepare this report. For the report’s conclusions, the committee draws both from existing literature and from its examination of a relatively small but varied selection of global change assessments, each analyzing global change processes that are at least in part driven by human activities.
This report presents a vision for the Earth science program; an analysis of the existing Earth Observing System and recommendations to help restore its capabilities; an assessment of and recommendations for new observations and missions for the next decade; an examination of and recommendations for effective application of those observations; and an analysis of how best to sustain that observation and applications system.
This report summarizes a workshop that focused on two case studies to provide different perspectives on multiple environmental stressors: 1) drought; 2) atmosphere-ecosphere interactions. Workshop participants identified the development of comprehensive regional frameworks for conducting environmental studies as a key part of understanding multiple environmental stresses.