Climate Warming, Forests and Hydroclimate Extremes in Southeast US Mountains

The mountains of the eastern United States have extensive forest cover that provides a wealth of ecosystem services, including carbon sequestration, flood regulation, and freshwater resources. However, increasing hydroclimate extremes including intense storms and drought fueled by climate change and shifting forest biodiversity threaten to undermine these benefits, producing greater risk and exposure of growing populations in and downstream of our forest mountains. Adaptation strategies for impacted communities include structural reinforcement, drainage infrastructure, land use planning, forest management, and improved forecast systems. 

Hurricane Helene resulted in catastrophic flooding and land sliding in western Virginia and North Carolina in late September of this year. While heavy rains from the hurricane were forecast, the scale of destruction and impact on urban and rural communities was unexpected and devastating. Boosted by orographic uplift to elevations of 4000-6000 feet and then interacting with a stalled cold front, Helene was the deadliest inland hurricane on record, exceeded only by Camille in 1969 in Nelson County. Hundreds of landslides in the steep mountain slopes cascaded into narrow canyons and funneled into mainstream. Debris jams from landslides and massive storm runoff contributed to unprecedented high-water levels and destructive erosion. Three-day total rainfall peaked at more than 750 mm over the mountains east of Asheville, with extensive areas receiving rainfall exceeding 1000-year events. In terms of the human toll, both large urban and small rural towns were severely impacted. 

This project will build a set of remote sensing/modeling tools that leverage our past research on forest mountain resilience to major storms to produce both long-term expectations of flood and landslide hazards and short to real-time emergency hazard forecasts. The integration and leveraging of these products into our advancing workflows will produce a technology basis for both fundamental new knowledge development, for hazard mitigation forecasting and planning, and to develop large new research and translational research proposals.