Field photos of burned forest and graphs showing reflectance properties.
Field measurement sites in high (top left) and moderate (top right) burn severity forests with the foreground of the latter showing burned debris and needles deposited onto the snow surface. The plots below show reflectance properties of snow albedo for unburned (gold), moderate burn severity (orange) and high burn severity (red) during January (Caldor), February (Creek Fire) and April (Creek Fire). The lower reflectance magnitudes for higher burn severity sites implies higher amount of energy available for snowmelt during winter and therefore earlier loss of the snowpack. Credit: Hatchett et al. [2023], Figure 2(c-e)
Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: Geophysical Research Letters

Wildfires in California during 2020 and 2021 show an abrupt change in their regime as compared to the prior two decades. As fires reach zones of seasonal snowpack the question is: what are the mechanisms in which they can affect watershed hydrology?

While there has been much research on impacts during warm seasons, Hatchett et al. [2023] show that post-fire effects can influence processes during the snow period. Specifically, the reduction of canopy cover and the decline of snow reflectance due to the deposition of burned material on snowpack in burned forests can enhance mid-winter snowmelt, leading to detectable changes in snow quantity. These findings call for improved assessments of seasonal water resource distribution in fire-impacted landscapes. 

Hatchett, B. J., Koshkin, A. L., Guirguis, K., Rittger, K., Nolin, A. W., Heggli, A., et al. (2023). Midwinter dry spells amplify post-fire snowpack decline. Geophysical Research Letters, 50, e2022GL101235. https://doi.org/10.1029/2022GL101235

—Valeriy Ivanov, Editor, Geophysical Research Letters

Text © 2023. The authors. CC BY-NC-ND 3.0
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