Climate, wildfire, and erosion ensemble foretells more sediment in western USA watersheds

Joel B. Sankey; Jason R. Kreitler; Todd Hawbaker; Jason L. McVay; Mary Ellen Miller; Erich R. Mueller; Nicole M. Vaillant; Scott E. Lowe; Temuulen T. Sankey

doi:10.1002/2017gl073979

USGS · 70190547

Climate, wildfire, and erosion ensemble foretells more sediment in western USA watersheds

Joel B. Sankey·Jason R. Kreitler·Todd Hawbaker·Jason L. McVay·Mary Ellen Miller·Erich R. Mueller·Nicole M. Vaillant·Scott E. Lowe·Temuulen T. Sankey

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Abstract

The area burned annually by wildfires is expected to increase worldwide due to climate change. Burned areas increase soil erosion rates within watersheds, which can increase sedimentation in downstream rivers and reservoirs. However, which watersheds will be impacted by future wildfires is largely unknown. Using an ensemble of climate, fire, and erosion models, we show that post-fire sedimentation is projected to increase for nearly nine-tenths of watersheds by > 10% and for more than one-third of watersheds by > 100% by the 2041 to 2050 decade in the western USA. The projected increases are statistically significant for more than eight-tenths of the watersheds. In the western USA, many human communities rely on water from rivers and reservoirs that originates in watersheds where sedimentation is projected to increase. Increased sedimentation could negatively impact water supply and quality for some communities, in addition to affecting stream channel stability and aquatic ecosystems.

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Joel B. Sankey, Jason R. Kreitler, Todd Hawbaker, Jason L. McVay, Mary Ellen Miller, Erich R. Mueller, Nicole M. Vaillant, Scott E. Lowe, Temuulen T. Sankey. 2017-09-07. Climate, wildfire, and erosion ensemble foretells more sediment in western USA watersheds. https://doi.org/10.1002/2017gl073979

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