As for the future of flora and fauna in subalpine and alpine regions like Niwot Ridge, there will be "winners and losers" as the climate warms, said Williams. Animals like American pikas, potato-sized denizens of alpine talus slopes in the West, need heavy snowpack to insulate them from cold winters as they huddle in hay piles beneath the rocks. In lower, more isolated mountain ranges in Nevada, researchers are already seeing a marked decline in American pika populations.
The predictions of the study authors are that microbes, plants and animals that depend on snow and ice will decrease if they are unable to move higher into areas of snow and ice. But shallower snow could cause big game like deer and elk to move higher in altitude to browse, according to the authors.
A big concern in temperate mountains like Colorado is the heath and welfare of coniferous trees as the climate changes, said Williams. "Trees in Colorado's mountains are under a tremendous amount of stress due to drought and pine beetle outbreaks. And the fire danger, at least now, is through the roof," he said.
"If some of these forested areas disappear, I think the chances of them coming back are pretty low," Williams said. "The climate they grew up in doesn't exist anymore. As we lose trees to drought, beetles and wildfires, we are likely to see an invasion of grasses and shrubs in areas where we have never seen them, causing a complete restructuring of our forest community."
As snowline moves up due to warming temperatures, so will parts of alpine tundra in the West, Williams said. "The tundra may be able to function reasonably well for several decades -- it will be awhile before warming climate change pushes the tundra off the tops of mountains. But that is the direction we are heading."
|Contact: Mark Williams|
University of Colorado at Boulder