A vicious cycle of heat and drought is pushing wildfires to higher elevations, threatening the winter snowpack critical for water supplies across the Western U.S. a recent study shows. The research, published last week in the Proceedings of the National Academy of Sciences, finds the snowpack in areas like those burned by major 2020 Colorado wildfires melted nearly a month earlier than in comparable, unburned areas — due in large part to the charred (and darker) vegetation and soot on the snow absorbing more heat from the sun.
Across the West’s “late snow zone” where snow normally persists until May but is now melting 18-24 days earlier, 70% have experienced an increase in wildfire activity since 1984. Historically slow-melting snowpack is a main water source in the West, and the weeks-early melting at higher altitudes poses “a major threat to a critical water reservoir for the region,” CSU scientist and co-author of the paper Dan McGrath, told the Washington Post. (Washington Post $, High Country News, Courthouse News; Climate signals background: 2020 Western wildfire season, Western U.S. megadrought)