These data show all the postfire erosion results affiliated with this data release summed by wildfire and attached to a polygon of each fire perimeter, as defined by Monitoring Trends in Burn Severity (MTBS). The results are shown as attributes for each polygon of wildfire perimeter. Some of the original MTBS data (name, ignition date, and ID) were preserved to allow for joining to other MTBS data. Results include WEPP modeling results of hillslope and channel erosion, a sum of postfire debris flow modeling results and field-based measurements, and a few derived results such as total sediment and total yield (mass per area).

This is a shapefile containing polygons of watersheds that were burned in wildfires that occurred in California between 1984 and 2021. The Water Erosion Prediction Project (WEPP) model for postfire erosion was run on all watersheds for the first year following wildfire and the results of this modeling effort are included as attributes of each watershed polygon.

This table contains measured and modeled postfire debris flow volumes alongside the associated sources for debris flow documentation, locations, and volumes. We conducted a search of scientific literature and news media reports to find documentation of debris flows that may have followed all wildfires greater than 100 square kilometers that occurred between 1984 and 2021 in California. The wildfires listed are all the fires we found that had documented postfire debris flows. Some fires had field-measurements of debris flow volume. Where field-measurements of volume did not exist, we used model data on postfire debris-flow likelihood and volume from U.S. Geological Survey Emergency Assessment of Post-Fire Debris-Flow Hazards Team (see Lineage section in this metadata). In some cases, exact locations (but not volumes) were known, in which case we used modeled volumes for these locations. Where debris flows were documented but not exact locations, we used the volumes from all basins with a probability greater than eighty percent of having postfire debris flows.

This table contains measured and modeled postfire debris flow volumes alongside the associated sources for debris flow documentation, locations, and volumes. We conducted a search of scientific literature and news media reports to find documentation of debris flows that may have followed all wildfires greater than 100 square kilometers that occurred between 1984 and 2021 in California. The wildfires listed are all the fires we found that had documented postfire debris flows. Some fires had field-measurements of debris flow volume. Where field-measurements of volume did not exist, we used model data on postfire debris-flow likelihood and volume from U.S. Geological Survey Emergency Assessment of Post-Fire Debris-Flow Hazards Team (see Lineage section in this metadata). In some cases, exact locations (but not volumes) were known, in which case we used modeled volumes for these locations. Where debris flows were documented but not exact locations, we used the volumes from all basins with a probability greater than eighty percent of having postfire debris flows.

These data were used to examine how post-fire sedimentation might change in western USA watersheds with future fire from the decade of 2001-10 through 2041-50. The data include previously published projections (Hawbaker and Zhu, 2012a, b) of areas burned by future wildfires for several climate change scenarios and general circulation models (GCMs) that we summarized for 471 watersheds of the western USA. The data also include previously published predictions (Miller et al., 2011) of first year post-fire hillslope soil erosion from GeoWEPP that we summarized for 471 watersheds of the western USA. We synthesized these summarized data in order to project sediment yield from future fires for 471 watersheds through the year 2050 at the hydrologic unit 8 (HUC8) scale. The detailed methods, results, and original data sources (i.e.: Hawbaker and Zhu, 2012a, b; Miller et al., 2011) were reported in the manuscript.

These data were used to examine how post-fire sedimentation might change in western USA watersheds with future fire from the decade of 2001-10 through 2041-50. The data include previously published projections (Hawbaker and Zhu, 2012a, b) of areas burned by future wildfires for several climate change scenarios and general circulation models (GCMs) that we summarized for 471 watersheds of the western USA. The data also include previously published predictions (Miller et al., 2011) of first year post-fire hillslope soil erosion from GeoWEPP that we summarized for 471 watersheds of the western USA. We synthesized these summarized data in order to project sediment yield from future fires for 471 watersheds through the year 2050 at the hydrologic unit 8 (HUC8) scale. The detailed methods, results, and original data sources (i.e.: Hawbaker and Zhu, 2012a, b; Miller et al., 2011) were reported in the manuscript.

These data were used to examine how post-fire sedimentation might change in western USA watersheds with future fire from the decade of 2001-10 through 2041-50. The data include previously published projections (Hawbaker and Zhu, 2012a, b) of areas burned by future wildfires for several climate change scenarios and general circulation models (GCMs) that we summarized for 471 watersheds of the western USA. The data also include previously published predictions (Miller et al., 2011) of first year post-fire hillslope soil erosion from GeoWEPP that we summarized for 471 watersheds of the western USA. We synthesized these summarized data in order to project sediment yield from future fires for 471 watersheds through the year 2050 at the hydrologic unit 8 (HUC8) scale. The detailed methods, results, and original data sources (i.e.: Hawbaker and Zhu, 2012a, b; Miller et al., 2011) were reported in the manuscript.

These data show model estimates of debris flow likelihood and volume that may be produced by a storm in a recently burned landscape. The scientific methods used by the U.S. Geological Survey Emergency Assessment of Post-Fire Debris-Flow Hazards were changed following 2015, and these shapefiles are a re-release of ten fires that occurred between 1997 and 2015 fires, using the updated methods. These ten fires were re-run to provide estimates of debris flow volumes as post-fire debris flows were documented but no field measurements were published.

These data show model estimates of debris flow likelihood and volume that may be produced by a storm in a recently burned landscape. The scientific methods used by the U.S. Geological Survey Emergency Assessment of Post-Fire Debris-Flow Hazards were changed following 2015, and these shapefiles are a re-release of ten fires that occurred between 1997 and 2015 fires, using the updated methods. These ten fires were re-run to provide estimates of debris flow volumes as post-fire debris flows were documented but no field measurements were published.

Following wildfire, mountainous areas of the western United States are susceptible to enhanced runoff and erosion and an increased vulnerability to debris flow during intense rainfall. Convective storms that can generate debris flows in recently burned areas may occur during or immediately after the wildfire, leaving insufficient time for development and implementation of risk mitigation strategies. We present a method for estimating post-fire debris-flow hazards prior to wildfire using historical data to define the range of potential fire severity for a given location based on the statistical distribution of severity metrics obtained from remote sensing. Estimates of debris-flow likelihood, magnitude and triggering rainfall threshold based upon the statistically simulated fire severity data provide hazard predictions consistent with those calculated from fire severity data collected after wildfire. Simulated fire severity data also produce hazard estimates that replicate observed debris-flow occurrence, rainfall conditions, and magnitude at a monitored site in the San Gabriel Mountains of southern California. Future applications of this method should rely upon a range of potential fire severity scenarios for improved pre-fire estimates of debris-flow hazard. The method presented here is also applicable to modeling other post-fire hazards, such as flooding and erosion risk, and for quantifying historic trends in fire severity in a changing climate. This release contains the data used to derive the historical distributions of fire severity, including a) the data used to derive a Weibull cumulative distribution function to historical measures of the differenced normalized burn ratio for fires >= 4 square kilometers (1000 acres) that burned between 2001 and 2014 in the western United States, b) the shape and scale parameters for the Weibull cumulative distribution function for every class of existing vegetation type, and the statistics describing goodness-of-fit of the Weibull distribution to these data, and c) the data used to determine the BARC4 threshold defining the break between pixels burned at low and moderate or high severity.