Scientists explore link between dust, snowpack

By digging in the muck of Rocky Mountain ponds and lakes, scientists have been able to establish an accurate historic record of how human activities have increased the amount of dust falling on high country snowpack. Using satellite images and analyzing the dust, other researchers have been able to pinpoint specific sources, including off-road vehicle disturbances, livestock grazing and oil and gas development on the Colorado Plateau. “It's profound,” said researcher Tom Painter, director of the snow optics laboratory at the University of Utah. “Areas that are actively disturbed release 1,000 times more dust,” Painter said, adding that dust layers in 2009 caused the snow pack to melt 45 to 48 days earlier than normal. Areas that haven't been disturbed by human activities release very little dust, Painter said. “This has huge impacts on hydrology and snow cover,” Painter said, explaining that water managers have to account for changes in runoff as they plan the operation of reservoirs and diversions. Painter said research in the last few years has enabled scientists to look back about 5,000 years. Lake sediments show a dramatic increase in dust deposition coincided with the settlement of the West, beginning in the late 1800s, he explained. The dust levels stayed high through the early 1900s and then declined in the 1930s, when new grazing laws changed the way ranchers ran their herds of cattle. Overall, the amount of dust being released since the advent of human disturbance is 500 times greater than prior to the disturbance of the West, Painter said...DailyNews