ENVIRONMENT
Dust From Great Salt Lake Negatively Impacts Utah Snowpack
Dec 21, 2018, 6:17 PM | Updated: Dec 22, 2018, 4:45 pm
SALT LAKE CITY, Utah – A study published by a University of Utah researcher shows the shrinking Great Salt Lake has had an unexpected negative impact on Utah’s snowpack.
Experts believed that impact could diminish our water supply and shorten the ski season on the Wasatch Front.
Utah not only depends upon “The Greatest Snow on Earth” for skiing and snowmobiling, everyone needs that snowmelt for drinking water and to water lawns.
Declining water levels on the lake have exposed more earth. That exposed dust is one of the culprits melting Utah’s snow faster in the mountains.
“I basically came to ski,” said McKenzie Skiles, the lead author of the study and an assistant professor of geography at the University of Utah.
Skiles first wondered about the impact of dust on snow while backcountry skiing in Utah as an undergraduate student more than 10 years ago.
“I noticed that there was dust on snow deposition,” she said. “I didn’t really think about the impact at that point.”
As a mountain hydrologist, she started to understand how snow, darkened by dust, accelerates snowmelt, and started to study the process in Colorado. Two years ago, she started studying dust deposits in snow near Alta.
“I really wanted to understand if dust was impacting our snowmelt, and by how much,” she said.
Possibly, more rapid snowmelt does shift evapotranspiration rates, which can lead to lower water yields- we’ll need a few more years studying this to fully understand this feedback, and how it compares to/compounds the water loss due to upstream water withdrawals.
— Dr. McKenzie Skiles (@UTSnowHydro) December 21, 2018
Her team discovered large dust deposits throughout the spring, and focused on a dust storm in April 2017.
“We hypothesized that part of the dust might be coming from the dry lake bed of the Great Salt Lake,” she said. “When we did some computer simulations of that dust event, we (confirmed) the dust was coming from the dry lake bed. That’s really interesting because the Great Salt Lake has been in steady decline.”
Skiles’ research determined the dust storm accelerated snowmelt that spring by a week. Combined with other dust deposits, snowmelt was 25 percent faster that spring.
“(The exposed lake bed) will continue to be a dust source into the future,” she said.
The low Great Salt Lake water levels can be seen from the Layton foothills looking toward the Oquirrh Mountains on Friday, Dec. 21, 2018. (The low Great Salt Lake water levels can be seen from the Layton foothills looking toward the Oquirrh Mountains on Friday, Dec. 21, 2018.)
Skiles and other researchers have studied even faster melting in southwestern Colorado.
“The dust in southern Colorado Rockies accelerates melt by a month on average, and up to two months in really heavy dust deposition years,” she said.
The dust there, tinted red by iron, melts snow even faster. Skiles said it’s the most important factor in snowmelt in that region.
“Air temperature doesn’t even play a role in snowmelt there because the dust impact is so dramatic,” she said.
Skiles next planned to compare the impact of dust on snowmelt here in the Rockies with other mountains globally.
