Articles | Volume 19, issue 3
https://doi.org/10.5194/gmd-19-1157-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-19-1157-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
The Western United States Large Forest-Fire Stochastic Simulator (WULFFSS) 1.0: a monthly gridded forest-fire model using interpretable statistics
A. Park Williams
CORRESPONDING AUTHOR
Department of Geography, University of California, Los Angeles, Los Angeles, CA, USA
Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, Los Angeles, CA, USA
Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA
Winslow D. Hansen
Cary Institute of Ecosystem Studies, Millbrook, NY, USA
Caroline S. Juang
Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA
Department of Earth and Environmental Sciences, Columbia University, New York, NY, USA
John T. Abatzoglou
Management of Complex Systems Department, University of California, Merced, Merced, CA, USA
Volker C. Radeloff
SILVIS Lab, Department of Forest and Wildlife Ecology, University of Wisconsin, Madison, Madison, Wisconsin, USA
Bowen Wang
Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
Jazlynn Hall
Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA
Jatan Buch
Department of Earth and Environmental Engineering, Columbia University, New York, NY, USA
Gavin D. Madakumbura
Department of Geography, University of California, Los Angeles, Los Angeles, CA, USA
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A. Park Williams, Caroline S. Juang, and Karen C. Short
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The Western United States MTBS-Interagency Database of Large Wildfires, 1984–2024 (WUMI2024a) represents more than 22000 large (≥1 km2) wildfires in the western United States from 1984 through 2024, including maps of fire perimeters and areas burned. It was compiled from seven government datasets and quality controlled. This dataset will aid research on the causes and effects of wildfire in a changing world.
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We leverage machine learning techniques to construct a statistical model of grid-scale fire frequencies and sizes using climate, vegetation, and human predictors. Our model reproduces the observed trends in fire activity across multiple regions and timescales. We provide uncertainty estimates to inform resource allocation plans for fuel treatment and fire management. Altogether the accuracy and efficiency of our model make it ideal for coupled use with large-scale dynamical vegetation models.
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The Western United States MTBS-Interagency Database of Large Wildfires, 1984–2024 (WUMI2024a) represents more than 22000 large (≥1 km2) wildfires in the western United States from 1984 through 2024, including maps of fire perimeters and areas burned. It was compiled from seven government datasets and quality controlled. This dataset will aid research on the causes and effects of wildfire in a changing world.
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The second State of Wildfires report examines extreme wildfire events from 2024 to early 2025. It analyses key regional events in Southern California, Northeast Amazonia, Pantanal–Chiquitano, and the Congo Basin, assessing their drivers and predictability and attributing them to climate change and land use. Seasonal outlooks and decadal projections are provided. Climate change greatly increased the likelihood of these fires, and without strong mitigation, such events will become more frequent.
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EGUsphere, https://doi.org/10.5194/egusphere-2024-2284, https://doi.org/10.5194/egusphere-2024-2284, 2024
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Matthew W. Jones, Douglas I. Kelley, Chantelle A. Burton, Francesca Di Giuseppe, Maria Lucia F. Barbosa, Esther Brambleby, Andrew J. Hartley, Anna Lombardi, Guilherme Mataveli, Joe R. McNorton, Fiona R. Spuler, Jakob B. Wessel, John T. Abatzoglou, Liana O. Anderson, Niels Andela, Sally Archibald, Dolors Armenteras, Eleanor Burke, Rachel Carmenta, Emilio Chuvieco, Hamish Clarke, Stefan H. Doerr, Paulo M. Fernandes, Louis Giglio, Douglas S. Hamilton, Stijn Hantson, Sarah Harris, Piyush Jain, Crystal A. Kolden, Tiina Kurvits, Seppe Lampe, Sarah Meier, Stacey New, Mark Parrington, Morgane M. G. Perron, Yuquan Qu, Natasha S. Ribeiro, Bambang H. Saharjo, Jesus San-Miguel-Ayanz, Jacquelyn K. Shuman, Veerachai Tanpipat, Guido R. van der Werf, Sander Veraverbeke, and Gavriil Xanthopoulos
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This inaugural State of Wildfires report catalogues extreme fires of the 2023–2024 fire season. For key events, we analyse their predictability and drivers and attribute them to climate change and land use. We provide a seasonal outlook and decadal projections. Key anomalies occurred in Canada, Greece, and western Amazonia, with other high-impact events catalogued worldwide. Climate change significantly increased the likelihood of extreme fires, and mitigation is required to lessen future risk.
Yavar Pourmohamad, John T. Abatzoglou, Erin J. Belval, Erica Fleishman, Karen Short, Matthew C. Reeves, Nicholas Nauslar, Philip E. Higuera, Eric Henderson, Sawyer Ball, Amir AghaKouchak, Jeffrey P. Prestemon, Julia Olszewski, and Mojtaba Sadegh
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The FPA FOD-Attributes dataset provides > 300 biological, physical, social, and administrative attributes associated with > 2.3×106 wildfire incidents across the US from 1992 to 2020. The dataset can be used to (1) answer numerous questions about the covariates associated with human- and lightning-caused wildfires and (2) support descriptive, diagnostic, predictive, and prescriptive wildfire analytics, including the development of machine learning models.
Jatan Buch, A. Park Williams, Caroline S. Juang, Winslow D. Hansen, and Pierre Gentine
Geosci. Model Dev., 16, 3407–3433, https://doi.org/10.5194/gmd-16-3407-2023, https://doi.org/10.5194/gmd-16-3407-2023, 2023
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Jianning Ren, Jennifer C. Adam, Jeffrey A. Hicke, Erin J. Hanan, Christina L. Tague, Mingliang Liu, Crystal A. Kolden, and John T. Abatzoglou
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Mountain pine beetle outbreaks have caused widespread tree mortality. While some research shows that water yield increases after trees are killed, many others document no change or a decrease. The climatic and environmental mechanisms driving hydrologic response to tree mortality are not well understood. We demonstrated that the direction of hydrologic response is a function of multiple factors, so previous studies do not necessarily conflict with each other; they represent different conditions.
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Short summary
The new Western United States Large Forest Fire Stochastic Simulator (WULFFSS) is a monthly gridded model to simulate forest fires across the western United States in response to vegetation, topographic, anthropogenic, and climate factors. The model is highly skillful, accounting for over 80 % of the observed variability in annual forest-fire area and capturing observed spatial, intra-annual variations, and trends.
The new Western United States Large Forest Fire Stochastic Simulator (WULFFSS) is a monthly...