USGCRP has a legal mandate to conduct a state-of-the-science synthesis of climate impacts and trends across U.S. regions and sectors every four years, known as the National Climate Assessment (NCA). The fourth, and most recent, NCA is being conducted in two volumes. 

 

NCA4 Volume I (Climate Science Special Report), released in November 2017, covers observed and projected changes in the physical climate system. Volume II (Impacts, Risks, and Adaptation in the United States), released in November 2018, focuses on climate-related risks to humans and systems that support our well-being and economy.   

 

The NCA aims to inform natural resource and utility managers, public health officials, emergency planners, financial risk managers, and other stakeholders as they consider climate-related risks in their decision making. By distilling a large body of research into relevant, accessible language framed around risks to people and important resources, the assessment provides a means for connecting the scientific and management communities. It also serves as a more general educational resource about what’s at stake for society as a result of climate change.

 

 

USGCRP approaches assessment as a sustained process that enables integration of new information as it emerges. Sustained assessment products developed by USGCRP member agencies improve the thoroughness of the quadrennial report while serving particular stakeholder groups such as public health officials or food security decision makers.

  

An important part of the sustained assessment process is the development of a set of national climate change indicators that track conditions and trends related to climate over time. Climate-related indicators—which may be physical, ecological, or societal—can be used to understand how environmental conditions are changing, assess risks and vulnerabilities, and help inform resiliency and planning for climate impacts. For more information, explore USGCRP’s Indicators Platform.

 

“Scenarios” depict a range of plausible future conditions against which risks, vulnerability, and opportunities can be assessed at regional and national scales. As part of the sustained assessment process, Federal interagency groups have developed a suite of scenario products for use by the broader scientific community. USGCRP encourages researchers and decision makers to use these products in their work, which can inform future sustained assessment products.

  

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