The Center for Naval Analyses (CNA), a Pentagon-funded think tank, issued a report last year that called climate change a “serious national security threat.”

The U.S. intelligence apparatus has worked up the first national intelligence assessment to focus on the implications of climate change for U.S. national security by 2030.

“There is increasing attention on the hard security side of climate change, and officials in the Pentagon are starting to take the topic a lot more seriously,” said Richard Moss, a climate-change specialist with the World Wildlife Fund.