Landslide Sensitivity and Response to Precipitation Changes in Wet and
Dry Climates
Abstract
Slow-moving landslides are hydrologically driven. Yet, landslide
sensitivity to precipitation, and in particular, precipitation extremes,
is difficult to constrain because landslides occur under diverse
hydroclimatological conditions. Here we use standardized open-access
satellite radar interferometry data to quantify the sensitivity of 38
landslides to both a record drought and extreme rainfall that occurred
in California between 2015 and 2020. These landslides are hosted in
similar rock types, but span more than ~2 m/yr in mean
annual rainfall. Despite the large differences in hydroclimate, we found
these landslides exhibited surprisingly similar behaviors and hydrologic
sensitivity, which was characterized by faster (slower) than average
velocities during wetter (drier) than average years, once the impact of
the drought diminished. Our findings may be representative of future
landslide behaviors in California where precipitation extremes are
predicted to become more frequent with climate change.