The early pandemic years overlapped with some of California’s worst wildfires on record, creating haunting, orange-tinted skies and wide swathes of burned landscape. Some of the impacts of these fires are well known, including drastic declines in air quality, and now a new study shows how these wildfires combined with midwinter drought conditions to accelerate snowmelt.
In a study published Jan. 20 in Geophysical Research Letters, a DRI-led research team examined what happens to mountain snowpacks when sunny, midwinter dry spells occur in forests impacted by severe wildfire. The researchers found a substantial increase in wildfires burning in California’s snowy landscapes throughout 2020 and 2021, when large blazes like the Dixie, Caldor, and Creek fires concentrated in snow zones. Using a 2013 midwinter dry spell as comparison, they found that similar weather in the winter of 2021-2022 led to 50% less snow cover. The compounding impacts of wildfire on snow melt include an increase in sun exposure due to loss of forest canopy, and a reduction in the snow’s ability to reflect sunlight.
“It’s already established that wildfires are increasing spring snow melt, but we wanted to know what happens when you add a long winter dry spell on top of that,” said Arielle Koshkin, M.S., a Ph.D. student now at the Colorado School of Mines who co-led the study as part of her master’s research at DRI and the University of Nevada, Reno. “The Caldor fire burned in our backyard, it was so close to where we live and work. So, the following winter, we wanted to investigate what it looked like.”
Read more at: Desert Research Institute
Snow under burned trees from the Caldor fire. The new study shows that snow melted more rapidly during midwinter drought conditions within the footprints of wildfires. (Photo Credit: Anne Heggli, DRI)