Articles | Volume 24, issue 7
https://doi.org/10.5194/nhess-24-2359-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/nhess-24-2359-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Probabilistic assessment of postfire debris-flow inundation in response to forecast rainfall
Alexander B. Prescott
CORRESPONDING AUTHOR
Department of Geosciences, The University of Arizona, Tucson, AZ, USA
Luke A. McGuire
Department of Geosciences, The University of Arizona, Tucson, AZ, USA
Kwang-Sung Jun
Department of Computer Science, The University of Arizona, Tucson, AZ, USA
Katherine R. Barnhart
U.S. Geological Survey, Denver, CO, USA
Nina S. Oakley
California Geological Survey Burned Watershed Geohazards Program, Sacramento, CA, USA
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Fire in steep landscapes increases the potential for debris flows that can develop during intense rainstorms. To explore possible debris flow hazards, we utilize a computational model of the physical processes of debris flow initiation and runout. Such process-based models are computationally intensive and of limited use in rapid hazard assessments. Thus we build statistical surrogate of these physical models to examine how inundation footprints vary with rainfall intensity and time since fire.
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Short summary
Fire can dramatically increase the risk of debris flows to downstream communities with little warning, but hazard assessments have not traditionally included estimates of inundation. We unify models developed by the scientific community to create probabilistic estimates of inundation area in response to rainfall at forecast lead times (≥ 24 h) needed for decision-making. This work takes an initial step toward a near-real-time postfire debris-flow inundation hazard assessment product.
Fire can dramatically increase the risk of debris flows to downstream communities with little...
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