WASHINGTON — Climate change is accelerating, and it will place unparalleled strains on American military and intelligence agencies in coming years by causing ever more disruptive events around the globe, the nation’s top scientific research group said in a report issued Friday.

The group, the National Research Council, says in a study commissioned by the C.I.A. and other intelligence agencies that clusters of apparently unrelated events exacerbated by a warming climate will create more frequent but unpredictable crises in water supplies, food markets, energy supply chains and public health systems.

Hurricane Sandy provided a foretaste of what can be expected more often in the near future, the report’s lead author, John D. Steinbruner, said in an interview.

“This is the sort of thing we were talking about,” said Mr. Steinbruner, a longtime authority on national security. “You can debate the specific contribution of global warming to that storm. But we’re saying climate extremes are going to be more frequent, and this was an example of what they could mean. We’re also saying it could get a whole lot worse than that.”