A research paper published earlier this month warns that dirty snow melts faster, but predicts the increased use of clean energy can help protect the snowpack.

Airborne black carbon (BC) particles released by fossil fuel use can travel significant distances in the wind before landing on snow. While bright white clean snow reflects sunlight, darkened snow absorbs light and warms faster, causing the snow to prematurely melt. This leaves more of the mountain's dark terrain exposed, which absorbs even more sunlight and warms the surrounding air, causing regional climate change.

In a study published in Nature Communications in early October, A cleaner snow future mitigates Northern Hemisphere snowpack loss from warming, researchers Dalei Hao, Gautam Bisht, Hailong Wang, et al., modeled two scenarios examining BC particles and dust using Earth System Model simulations based on the Tibetan Plateau. 

In a Wired article examining the study, biology and environment writer Matt Simon explains that in the first scenario, the study’s authors considered a future without a huge change in fossil fuel use but “some improvement in clean energy technology.” There, the researchers predicted the Tibetan Plateau would lose nearly 60 percent of its snowpack by 2100, but a “modest upgrade in clean air technology” could reduce particulate pollution enough to bring that number down to 55 percent. 

Under the second scenario, however, researchers examined a future with significantly more clean energy technology and reduced fossil fuel use, which would result in less warming and air pollution. The difference was extraordinary: The Plateau would lose just 15 percent of its snowpack by the end of the century, and the reduction in particulates would lower that number further to only around 8 percent. 

“These results stress the importance of reducing combustion aerosol emissions by developing clean, renewable energy and negative-emission technologies, in addition to mitigating climate change,” the researchers concluded.

The good news? Snow quality rebounds quickly with decreased fossil fuel use. 

“When we start reducing the burning of fossil fuels, the tiny particles in the air don't last that long,” study co-author L. Ruby Leung told Simon. Simon adds that other researchers have observed that the significant drop in air pollution during the COVID-pandemic lockdowns also reduced pollution on snow and ice.

Still, Simon explains that other airborne particles contribute to dirty snow — like smoke particles from wildfires and dust from agricultural land use. Responsible forest management and farming practices can help minimize these impacts. But to dramatically reduce this trifecta of harm threatening the snowpack — black carbon emissions, smoke particles and dust — comprehensive climate action is desperately needed.