The report lays out a road map for how the military will adapt to rising sea levels, more violent storms and widespread droughts. The Defense Department will begin by integrating plans for climate change risks across all of its operations, from war games and strategic defense planning situations to a rethinking of the movement of supplies.

Defense Secretary Chuck Hagel, speaking Monday at a summit meeting of defense ministers in Peru, highlighted the report’s findings and the global security threats of climate change.

“The loss of glaciers will strain water supplies in several areas of our hemisphere,” Mr. Hagel said. “Destruction and devastation from hurricanes can sow the seeds for instability. Droughts and crop failures can leave millions of people without any lifeline, and trigger waves of mass migration.”