Rapid Response Research (RAPID) Proposal to NSF Hydrologic Sciences: Impacts of Forest Fire on Snow Accumulation and Melt

Oregon State University, Corvallis OR

Investigators

Abstract

Recent work documenting snow-vegetation interactions in burned and unburned forests show that burned forests experience increased snow accumulation but earlier and more rapid melt. Burned areas also experience higher wind speeds and as a result, increased sublimation losses and sensible heat inputs. At the local-to-watershed scale, wildfire-derived black carbon sloughing from burned trees onto the snowpack has been suggested as an additional important forcing of earlier melt and anecdotal evidence suggests that snowpacks in the wildfire areas appear to be experiencing this forcing. The effects of fire are likely to represent a new paradigm for snow-vegetation dynamics and their hydrologic impacts. This hydrologic research will focus on a recently burned headwaters catchment, Shadow Lake in the Oregon Cascades, which typically receives over 2 m of snow water equivalent each winter. This research will provide substantial direct results on the impacts of wildfire on snowpack accumulation and ablation and the magnitudes of the mechanisms involved. Paired sites will allow us to quantify site differences, 3-dimensional measurements will provide key vegetation structure information, transects provide information across burned-unburned gradients and between recent and older burn sites, and data from monitoring networks will provide key spatial and temporal contextual information. The results of this work will provide important insights into the hydrologic impacts of fire on snowpack dynamics with potential to redefine the paradigm of snow-vegetation interactions in fire-affected watersheds.