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On Colorado’s Western Slope or in southern Utah, you might notice the snow often has a dirty tinge: red dust. Carried by westerly winds, dust blows hundreds of miles from the deserts of central Utah and lands on the high peaks of the San Juans and Wasatch.
Dust can wreak havoc on snowpack. It creates weak layers that can cause massive wet slides once the snow warms up, and it accelerates snowmelt by lowering the albedo (reflectivity) of the snow surface, leading to faster heat absorption. This not only worsens avalanche danger in spring (a typically less avalanche-prone time), but leads to early and inconsistent spring runoff, threatening agricultural and drinking water statewide. This dirt-on-snow phenomenon is relatively new, and it’s most often attributed to grazing, development, and extended drought on the vast Colorado Plateau.
The problem is serious enough that Colorado funds the Colorado Dust On Snow Program (CODOS), a scientific effort aimed at better understanding the causes and effects of these dust deposits. CODOS maintains 11 mountain research stations around its Silverton base to gather data.
Learn more at codos.org.