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Observed increases in wildfire activity across the contiguous United States (U.S.), together with continued warming and expanding development in fire-prone landscapes, highlight the need to anticipate near-term changes in fire regimes. We apply a Bayesian statistical model that integrates projected population density (SSP2) and downscaled climate simulations under a moderate emissions scenario (RCP 4.5) to estimate future wildfire occurrence, maximum fire size (using the 90th percentile of fire size distribution), and total area burned for large fires (>1000 acres) across all EPA Level III ecoregions for 2020–2060. Relative to 1984–2019, we project nationwide increases of 56% in fire occurrence and 59% in area burned, with larger increases in maximum fire size (63%) in 2020–2060. Spatial patterns vary substantially: fire occurrence increases most strongly in the eastern U.S., including regions where large fires have historically been rare, while western ecoregions experience the largest absolute increases in burned area and extreme fire size. The disproportionate growth in maximum fire size suggests that changes in fire weather will amplify extreme events beyond increases in ignition frequency alone. These projections indicate expanding wildfire risk across diverse U.S. landscapes and underscore the need for regionally tailored fire management and preparedness strategies.
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This content will become publicly available on July 23, 2027
Fire weather waves drive extreme fires globally
Abstract We define fire weather waves as persistent extreme fire weather, which can intensify fire activity by sustaining exceptionally warm, dry, and windy conditions. Here, we use daily fire weather index, fire activity, and meteorological data to examine the impacts of fire weather waves on fires, as well as their patterns and trends across global terrestrial ecoregions. Fire weather waves account for only 4% of days but coincide with 26% of the area burned and nearly half of the top 1% most energetic fires in forested ecoregions. Compared with grassland and shrubland fires, forest fires exhibit a larger and more persistent increase in daily burned area in response to fire weather waves, particularly in Mediterranean forests. Fire weather wave frequency has significantly increased across most burnable lands during 1979–2024. Climate projections indicate that fire weather waves will increase throughout the 21st century. These findings underscore fire weather waves as an essential component of early warning systems to strengthen preparedness for extreme fires.
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- PAR ID:
- 10712750
- Publisher / Repository:
- Communications Earth and Environment
- Date Published:
- Journal Name:
- Communications Earth & Environment
- ISSN:
- 2662-4435
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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