Abstract
As climate warms, snow-water storage is decreasing while forest fires are increasing in extent, frequency, and duration. The majority of forest fires occur in the seasonal snow zone across the western US. Yet, we do not understand the broad-scale variability of forest fire effects on snow-water storage and water resource availability. Using pre- and post-fire data from 78 burned SNOTEL stations, we evaluated post-fire shifts in snow accumulation (snow-water storage) and snowmelt across the West and Alaska. For a decade following fire, maximum snow-water storage decreased by over 30 mm, and the snow disappearance date advanced by 9 days, and in high severity burned forests snowmelt rate increased by 3 mm/day. Regionally, forest fires reduced snow-water storage in Alaska, Arizona, and the Pacific Northwest and advanced the snow disappearance date across the Rockies, Western Interior, Wasatch, and Uinta mountains. Broad-scale empirical results of forest fire effects on snow-water storage and snowmelt inform natural resource management and modeling of future snow-water resource availability in burned watersheds.
Highlights
Across the western US, the majority of freshwater, critical for drinking, irrigation, industrial use, and ecosystem health, originates as snowpack in mountainous headwaters [1,2,3,4]
The volume of winter snow-water storage controls the volume of downstream water resources the following summer, while the timing of snowmelt is essential for the timing of downstream water resource availability [5,6,7]
Post-fire snow hydrologic hydrologic responses responses were were evaluated evaluated using using four four annual annual snow snow metrics metrics calculated for stations located within forest fire calculated for 78 Snow Telemetry (SNOTEL) stations located within forest fire perimeters perimeters burned from 1984–2019 in the eleven western states including, Arizona, California, Colorado, Idaho, Montana, New Mexico, Nevada, Oregon, Washington, Wyoming, and Utah, and Alaska (Figure 2, Table S1)
Summary
Across the western US, the majority of freshwater, critical for drinking, irrigation, industrial use, and ecosystem health, originates as snowpack in mountainous headwaters [1,2,3,4]. Headwater snow storage depends on accumulated snowpacks remaining cold with a negative snowpack energy balance into spring [8]. A warming climate is reducing snow-water storage, driving earlier snowmelt and lower summer stream flows, raising stream temperatures [4,5,6,7,9], and lengthening the summer drought and duration of the fire season [10]. Climate warming is shifting the timing of snowmelt earlier, lengthening the period of snowmelt, and slowing the rate of snowmelt [4,10,11]. Forest fires are increasing in frequency, extent, and duration, during the years of early snowmelt [12,13]. The vast majority of forest fires occur in the seasonal snow zone across the West [14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
