Rising wildfire activity and stronger rainfall in the western US have increased Post-Fire Debris Flow hazards (PFDF). The United States Geological Survey (USGS) employs the M1 model to evaluate PFDF likelihood, with basin-averaged differenced Normalized Burn Ratio (dNBR) as a primary input. The Thomas Fire reports non-normal dNBR distributions in 81% of basins, reducing the means’ capacity to capture burn heterogeneity. Here,...

Indicators of social vulnerability are frequently analyzed using methods that assume spatial stationarity, meaning that the relationships between these indicators and the outcome of interest are presumed to remain consistent across space. However, this assumption can obscure important variations if spatial heterogeneity is present, that is if the relationships between social vulnerability indicators and the outcome vary across...

Human exposure to floods continues to increase, driven by changes in hydrology and land use. Adverse impacts amplify for socially vulnerable populations, who disproportionately inhabit flood-prone areas. This study explores the geography of flood exposure and social vulnerability in the conterminous United States based on spatial analysis of fluvial and pluvial flood extent, land cover, and social vulnerability. Using bivariat...