Rockies' Snowpack Shrinking
by: Paul Foy 1 December 2006
The Rocky Mountains are seeing more rain than snow at the start and end of winter, an indication of global warming, an expert said.
Another sign of climate change: The spring snow melt is starting a week earlier than it did 50 years ago.
Both trends could shorten the ski season.
The Rockies, however, are expected to handle the changes better than New England, where low-elevation ski areas are more vulnerable to dwindling snowpacks.
And Utah and Colorado's ski areas, commonly found near 10,000 feet in elevation, could benefit from feeble winters in the East.
"They won't be able to ski in New England. They'll have to come to Utah," said Kevin Trenberth, a climate expert who gave a lecture Wednesday at the University of Utah.
Trenberth, head of the climate-analysis section of the National Center for Atmospheric Research in Boulder, Colo., said climate change could make the arid West even drier, setting loose other problems.
The dwindling snowpacks are more evident at lower elevations in the Rockies, leaving many of the ski areas secure for now, he said.
But combined with an earlier spring, shrinking snowpacks rob moisture from the soil at the start of growing season. "It sets the stage for drought," he said.
The West is experiencing more and larger wildfires in recent summers, he said.
Soil moisture - or the lack of it - is a critical factor for farmers and ranchers in mountain states.
Dry soils absorb snowmelt faster, leaving less runoff for mountain streams, which can't recharge reservoirs like Lake Powell, a source of water for 25 million people and irrigation for millions of acres from Colorado to California.
Lake Powell is barely half-full, reflecting a drought that took hold in 2000, government hydrologists say.
Trenberth said that drought may not be over yet, despite some recovery from the past two wet winters.
At the end of last winter, the Colorado Plateau snowpack looked substantial, but much of it evaporated into the air by May 1, Trenberth said.
Flashing charts, slides, streaming video and pictures of the "bathtub ring" left by a shrinking Lake Powell, Trenberth emphasized the problems of climate change.
Salt Lake City Mayor Rocky Anderson offered some solutions.
Anderson said he took action in 2001 to cut greenhouse-gas emissions from city operations by 21 percent. He planned to accomplish the reduction by 2012, but managed to achieve it last year.
City Hall switched to compact fluorescent light bulbs, using the savings on electricity to buy wind power.
Salt Lake City is changing traffic signals over to LED lights, saving $50,000 a year on its electric bill, he said.
Anderson said he downsized the city's fleet, trading 41 sport-utility vehicles for smaller cars. The city bought some three-wheeled utility vehicles. It's also powering some dump trucks with compressed natural gas - the same fuel Anderson uses for his own vehicle.
The mayor also embraced "green" buildings," signing an executive order that says all future city-owned buildings be built from energy-efficient designs and recycled materials. The methane released by the city and county landfill and a sewer plant is being captured to generate electricity.
Whether any corrective action can reverse climate change is uncertain.
Trenberth said the best to hope for is to slow climate change, not reverse it - to buy more time before the worst effects take hold.
"The carbon dioxide we have with us now is not going away," he said. "Global warming is guaranteed to continue to some extent."