Introduction
A primary goal of the U.S. National Climate Assessment (NCA) is to help the nation anticipate, mitigate, and adapt to impacts from global climate change, including changes in climate variability, in the context of other national and global change factors. Since 1990, when Congress authorized the U.S. Global Change Research Program (USGCRP) through the Global Change Research Act18 and required periodic updates on climate science and its implications, researchers from many fields have observed significant climate change impacts in every region of the United States. The accelerating pace of these changes (for example, the recent rapid reductions observed in the extent and thickness of Arctic sea ice), as well as scenario-based projections for future climate changes and effects, is articulated in this third NCA.
Based on recommendations stemming from the National Research Council (NRC), USGCRP in its most recent strategic plan6 identified the rationale and benefits of implementing a sustained assessment process. In response, a vision for a new approach to assessments took shape as the third NCA report was being prepared. The vision includes an ongoing process of working to understand and evaluate the nation’s vulnerabilities to climate variability and change and its capacity to respond. A sustained assessment, in addition to producing quadrennial assessment reports as required by law, recognizes that the ability to understand, predict, assess, and respond to rapid changes in the global environment requires ongoing efforts to integrate new knowledge and experience. It accomplishes this by: 1) advancing the science needed to improve the assessment process and its outcomes, building associated foundational knowledge, and collecting relevant data; 2) developing targeted scientific reports and other products that respond directly to the needs of federal agencies, state and local governments, tribes, other decision-makers, and end users; 3) creating a framework for continued interactions between the assessment partners and stakeholders and the scientific community; and 4) supporting the capacity of those engaged in assessment activities to maintain such interactions.
To provide decision-makers with more timely, concise, and useful information, a sustained assessment process would include both ongoing, extensive engagement with public and private partners and targeted, scientifically rigorous reports that address concerns in a timely fashion. A growing body of assessment literature has guided and informed the development of this approach to a sustained assessment.19,20,1,2,3
The envisioned sustained assessment process includes continuing and expanding engagement with scientists and other professionals from government, academia, business, and non-governmental organizations. These partnerships broaden the knowledge base from which conclusions can be drawn. In addition, sustained engagement with decision-makers and end users helps scientists understand what information society wants and needs, and it provides mechanisms for researchers to receive ongoing feedback on the utility of the tools and data they provide.
An ongoing process that supports these forms of outreach and engagement allows for more comprehensive and insightful evaluation of climate changes across the nation, including how decision-makers and end users are responding to these changes. The most thoughtful and robust responses to climate change can be made only when these complex issues, including the underlying science and its many implications for the nation, are documented and communicated in a way that both scientists and non-scientists can understand.
This sustained assessment process will lead to better outcomes for the people of the United States by providing more relevant, comprehensible, and usable knowledge to guide decisions related to climate change at local, regional, and national scales. Additional details about the components of the sustained assessment process are provided in “Preparing the Nation for Change: Building a Sustained National Climate Assessment Process,” the first special report of the National Climate Assessment and Development Advisory Committee.17