Essential Site Maintenance: Authorea-powered sites will be updated circa 15:00-17:00 Eastern on Tuesday 5 November.
There should be no interruption to normal services, but please contact us at [email protected] in case you face any issues.

loading page

Midwinter dry spells amplify post-fire snowpack decline
  • +9
  • Benjamin J Hatchett,
  • Arielle Koshkin,
  • Kristen Guirguis,
  • Rittger Karl,
  • Anne Nolin,
  • Heggli Anne,
  • Alan M. Rhoades,
  • Amy E East,
  • Erica R. Siirila-Woodburn,
  • W. Tyler Brandt,
  • Alexander Gershunov,
  • Kayden Haleakala
Benjamin J Hatchett
Desert Research Institute

Corresponding Author:[email protected]

Author Profile
Arielle Koshkin
Colorado School of Mines
Author Profile
Kristen Guirguis
Scripps Institution of Oceanography, Univ. California, San Diego
Author Profile
Rittger Karl
Institute of Arctic and Alpine Research, University of Colorado, Boulder
Author Profile
Anne Nolin
University of Nevada, Reno
Author Profile
Heggli Anne
Desert Research Institute
Author Profile
Alan M. Rhoades
Lawrence Berkeley National Laboratory
Author Profile
Amy E East
United States Geological Survey
Author Profile
Erica R. Siirila-Woodburn
Lawrence Berkeley National Laboratory (DOE)
Author Profile
W. Tyler Brandt
Scripps Institution of Oceanography
Author Profile
Alexander Gershunov
Scripps Institution of Oceanography, Univ. California, San Diego
Author Profile
Kayden Haleakala
University of California Los Angeles
Author Profile

Abstract

Increasing wildfire and declining snowpacks in mountain regions threaten water availability. We combine satellite-based fire detection with snow seasonality classifications to examine fire activity in California’s seasonal and ephemeral snow areas. We find a nearly tenfold increase in fire activity during 2020 and 2021 compared to 2001-2019 as measured by satellite data. Accumulation season snow albedo declined 17-77% in two burned sites as measured by in-situ data relative to un-burned conditions, with greater declines associated with increased soil burn severity. By enhancing snowpack susceptibility to melt, decreased snow albedo drove mid-winter melt during a multi-week midwinter dry spell in 2022. Despite similar meteorological conditions in 2013 and 2022, which we link to persistent high pressure weather regimes, minimal melt occurred in 2013. Post-fire differences are confirmed with satellite measurements. Our findings suggest larger areas of California’s snowpack will be increasingly impacted by the compounding effects of dry spells and wildfire.