The NAS website says that “the US intelligence community” is funding the project, and William Kearney, a spokesman for NAS, told Mother Jones that phrase refers to the CIA. Edward Price, a spokesman for the CIA, refused to confirm the agency’s role in the study, but said, “It’s natural that on a subject like climate change the Agency would work with scientists to better understand the phenomenon and its implications on national security.” The CIA reportedly closed its research center on climate change and national security last year, after GOP members of Congress argued that the CIA shouldn’t be looking at climate change.

Liebelson and Mooney note that the government’s interest in geoengineering dates back to the 1960s:

The first big use of weather modification as a military tactic came during the Vietnam War, when the Air Force engaged in a cloud seeding program to try to create rainfall and turn the Ho Chi Minh Trail into muck, and thereby gain tactical advantage. Between 1962 and 1983, other would-be weather engineers tried to change the behavior of hurricanes using silver iodide. That effort, dubbed Project Stormfury, was spearheaded by the Navy and the Commerce Department.

Kelsey D. Atherton points out that the military has good reason to worry about global warming:

Climate change, it turns out, is one of the major threats to national security, as specified in the 2013 “Worldwide Threat Assessment of the US Intelligence Community.” Climate change threatens food and water supplies, which in turn, could lead to all sorts of geopolitical conflicts. The intelligence community report singles out droughts in the “Nile, Tigris-Euphrates, Niger, Amazon, and Mekong river basins,” and notes that increased populations will put intense pressure on (already scarce) resources. This doesn’t speak to a direct, pressing security threat, but instead thousands of future problems.