Climate Crisis: Impact of Wildfires on Sierra Snow Melt

Scientists have found that snow in parts of the Sierra Nevada is melting faster than ever, and it’s not because of warmer temperatures.

In a study by the Desert Research Institute in Reno, scientists analyzed satellite data from past seasons, most recently from 2021-2022, when the Kaldor Fire broke out near South Lake Tahoe. They found that during dry spells in the middle of winter, burnout areas in the Sierra experienced significant snowmelt.

“During these mid-winter dry periods, we have found that it is possible to lose almost half of that snowpack due to melting, and in some lower places, even more,” said Benjamin Hatchett of the Desert Research Institute. “But in places higher in the mountains, where we don’t expect much change, even if it was dry after the fires, the snow melted much faster in these high altitude areas.”

The effects of wildfires on snowmelt include increased exposure to the sun due to loss of the forest canopy and reduced ability of snow to reflect sunlight, also known as albedo. In winter, immediately after a fire, the snow is covered with black carbon from burned vegetation, which can accelerate the rate of snow melt.

Scientists say that while extreme weather may become our new normal, we have the ability to adapt, manage and mitigate the effects.

“How do we deal with fire, actually by adding more fire,” Hatchett said. “We need good fire, or low-severity prescribed fire, or cultural fires to rebalance these systems that have had good fire taken from them for hundreds of years at this point.”