Mountains are warming faster than valleys, hurting water supply in the West

A new global review examined more than 200 studies on how climate change is affecting high-elevation environments. The researchers found that rising temperatures are changing the way winter works in mountain landscapes: more storms are falling as rain instead of snow, and the snow that does accumulate is disappearing earlier in the spring.

Those changes disrupt the natural "water-tower" function that mountains play for much of the West, said John Knowles, a researcher at Montana State University and a co-author of the study.

"They collect precipitation all winter long," Knowles said. "They store it as snowpack, and then they release it slowly as nature's drip irrigation system all summer long, when we need it the most."

But with warming trends accelerating at high elevations, that s