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Published on: November 14, 2017
High-severity fire now dominant in California forests
Mitchell J Hung1,2, A Park Williams1,3
1Department of Geography, University of California-Los Angeles, Los Angeles, CA 90095.
Summary
California
Area of Science:
- Forest ecology
- Environmental science
- Remote sensing
Background:
- Forest fires are critical ecological drivers globally.
- California has seen a dramatic increase in annual forest fire area.
- Understanding burn severity trends is vital for policy and management.
Purpose of the Study:
- To assess trends and drivers of burn severity in California forests.
- To develop high-resolution maps of fire severity using remote sensing.
- To analyze data from 1985-2024 for 4,391 forest fires.
Main Methods:
- Development of high-resolution, remotely sensed fire severity maps.
- Analysis of 4,391 forest fires across California.
- Assessment of burn severity trends and contributing factors from 1985-2024.
Main Results:
- A significant shift from low-severity to high-severity fire has occurred since 2012.
- High-severity, stand-replacing fires are now the most common class.
- This trend is most pronounced in high-biomass forests, linked to fuel loads from fire exclusion.
Conclusions:
- California's forests are increasingly experiencing fires of unsustainable severity.
- This shift threatens forest resilience and the ecosystem services they provide.
- The rise in high-severity fires will likely incur substantial socioeconomic costs.
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