Researchers from Colorado State University focused on areas they call “late snow zones” – regions in the Western mountains where snow doesn’t typically melt until May or later.
They found that between 1984 and 2020, wildfire activity increased in 70% of these zones throughout the West. The mountain ranges studied included the Sierra Nevada, Cascades, Basin and Range, and Northern and Southern Rockies.
In the Southern Rockies, specifically, more forest burned in late-melt snow zones in 2020 than in the previous 36 years combined.
These burn scars at higher elevations, the researchers discovered, affect how much snow the mountains can hold, and for how long.
Dan McGrath, an assistant professor of geosciences at Colorado State University who co-authored the study, says the findings have big implications for water supplies around the West.
“Less snow accumulated in the burned areas compared to the nearby unburned areas,” McGrath said. “Further, we found that the snowpack melted out much earlier – as much as seven to 14 days earlier at high-elevation sites, and 27 days earlier at lower elevation sites.”
McGrath says this accelerated melting comes at a time when the West’s snowpack has already dropped by 15% to 30% over the last 70 years due to climate change.
This story was produced by the Mountain West News Bureau, a collaboration between Wyoming Public Media, Nevada Public Radio, Boise State Public Radio in Idaho, KUNR in Nevada, the O'Connor Center for the Rocky Mountain West in Montana, KUNC in Colorado, KUNM in New Mexico, with support from affiliate stations across the region. Funding for the Mountain West News Bureau is provided in part by the Corporation for Public Broadcasting.
