That old culprit DUST is causing snow and glacial melting. Who would ever have thought that? First it was volcanoes putting out the dust or ash, then it was forest fires and "slash and burn" agricultural methods. Now researchers in the American west correlate the dust to man's activities in the dusty, dry deserts.
How does this coincide with the concept that carbon dioxide emissions are causing all of the global warming? I bet someone will come up with the idea of selling "dust credits". I smell the stench of more laws, more lawsuits, more "documentary films".
Peter
from: http://www.denverpost.com/ci_6228554
denver & the west
Dusty snow blamed for faster melting
By Katy Human Denver Post Staff Writer
Desert dust loosened by cattle's hooves and miners' machinery is blowing onto Colorado's snowcapped mountains, catching the sun and making snow melt faster, according to a new report.
More than a month faster.
"The snowpack 150 years ago was probably much cleaner, and by being cleaner, it lasted longer, potentially weeks longer," said Tom Painter, a researcher with the National Snow and Ice Data Center in Boulder.
The faster melt means less water late in the summer for farmers relying on flowing streams, and less for city water providers, who also use mountain snowpacks to store water for later in the summer, Painter said.
Dirty snow could also mean more warming in the region, he said, as white snow reflects solar radiation back into space, and dark grit absorbs heat.
In 2006, eight dust storms from northern Arizona and New Mexico covered Colorado's San Juan Mountains with layers of orange and red grit, Painter and his colleagues reported. In most years there are fewer than four such dust storms.
Last year's dusty snow melted 24 to 35 days earlier than in dust-free years, the scientists reported, based on computer water models and ground data.
The study is published online and in the current edition of Geophysical Research Letters.
Joe Sloan, a community-relations expert with Denver Water, said the study bodes poorly for the region.
Fast melting can increase flood risk, Sloan said, "and when melt is slower, it's easier to manage, it's a better resource from the water provider's view."
The new findings are not limited to Colorado's San Juan Mountains, Painter said.
"Around the world, but particularly in the Southwest, it appears that dust emission has increased," Painter said.
Researchers have even found evidence that windstorms increasingly coat Antarctica's high peaks with dust - sent there from Patagonia, where intensified sheep grazing has damaged soils, according to Joseph McConnell of the Desert Research Institute based in Reno, Nev.
Jayne Belnap, a U.S. Geological Survey ecologist in Moab, Utah, said that in the West, cattle, people, the military and energy exploration are to blame for disturbing the region's delicate soils.
"The idea that deserts create lots of dust naturally doesn't fly," said Belnap, who was not directly involved in the study.
Staff writer Katy Human can be reached at 303-954-1910 or khuman@denverpost.com.
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