Climate & national securityNational security in the Fourth National Climate Assessment

Published 30 November 2018

NCA4 vol. 2: “Climate change presents added risks to interconnected systems that are already exposed to a range of stressors such as aging and deteriorating infrastructure, land-use changes, and population growth. Extreme weather and climate-related impacts on one system can result in increased risks or failures in other critical systems, including water resources, food production and distribution, energy and transportation, public health, international trade, and national security. The full extent of climate change risks to interconnected systems, many of which span regional and national boundaries, is often greater than the sum of risks to individual sectors.”

On Friday, 23 November 2018, the Fourth National Climate Assessment Volume II was released. NCA4 Vol II, Impacts, Risks, and Adaptation in the United States, assesses a range of potential climate change-related impacts, with an aim to help decision makers better identify risks that could be avoided or reduced. The assessment follows Vol I, the Climate Science Special Report (CSSR), which was released in November 2017. Together, these reports meet the requirements of the Global Change Research Act, which mandates a quadrennial assessment of our understanding of global change and its impacts on the United States.

The last NCA3 was released in 2014. The Center for Climate and Security (CCS) notes that one of the main “Topics for Consideration in Future Assessments” was “National Security.” As such, there was a significant increase in the coverage of national security matters in this latest National Climate Assessment. This is consistent with assessments coming from both the Department of Defense and the National Intelligence Council during this Administration.

Below is a list of only the explicit mentions of climate change impacts on national security and the military in the report. The full assessment also covers broader human, food, water, and energy security matters, which can certainly have national security implications, so we encourage readers interested in climate and security to explore the whole report.

National security in the Fourth National Climate Assessment
The text below contains direct excerpts from the “Report-in-Brief” and the individual chapters, highlighting explicit mentions of climate change impacts on “national security” and the “military.”