RAPID: Death Valley after Hurricane Hilary: A study of desert landscape re-equilibration after extreme events

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

On August 20, 2023, the first tropical storm to hit California since the 1930’s traversed Death Valley National Park. Total of 2.2 inches of rain fell over the park in a single day, setting a new record equivalent to the park’s average annual rainfall. This led to unprecedented flooding and landscape change, the extent of which is still being determined. During normal conditions, Death Valley is among the most arid places in the world with landscape change driven by wind and infrequent alluvial and fluvial activity. In the aftermath of Hurricane Hilary, widespread flash flooding and debris flows carved deep channels will fundamentally alter the landscape providing an unprecedented opportunity to learn about the rates and drivers of landscape change following extreme events. This work will identify meter- to hundred-meter-scale changes caused by the storm and quantitatively document the post-storm landscape state. The immediate results of debris flows, flooding, and associated erosion define the boundary condition for future landscape development and recovery. This baseline landscape state is actively decaying and must be rapidly documented to address scientific questions related to landscape change in the wake of extreme events including What are the timescales of landscape re-equilibration at meter- to hundred-meter scales? How do extreme events redistribute or create new sources and sinks of sediment? How does vegetation recover in the wake of an extreme event? Exploring these questions requires the proposed baseline dataset that will be collected in this effort. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.