ARS | Publication request: Evaluation of sediment hazards by extreme rainfall in wildfire lands

Submitted to: Trans American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: September 16, 2011
Publication Date: December 4, 2011
Citation: Shin, S., Park, S., Pierson Jr, F.B. 2011. Evaluation of sediment hazards by extreme rainfall in wildfire lands. Trans American Geophysical Union.

Technical Abstract: Extreme rainfall events in mountainous terrain impacted by wildfire can erode hillslopes and stream channels and produce flooding with large sediment yields. In 2002, typhoon Rusa with a one-day rainfall total of 944.5 mm and a maximum one-hour rainfall intensity of 114.5 mm/hr hit land impacted by wildfire in South Korea. The intense storm caused 10 times as many landslides in areas that were burned forest compared to unburned forest. Sediment yields from hillslope-scale experimental plots increased by heavy rain, but decreased with degree of vegetation recovery following fire. Measured sediment yields increased over 40 times at the hillslope-scale and over 800 fold at the watershed-scale. RUSLE, WEPP and SEMMA underestimated sediment yields by 52 %, 62 %, and 75 %, respectively at the hillslope-scale and over- or under-estimated sediment yields by 174.4 %, 46.0 %, and 3.9 %, respectively at the watershed-scale. These results indicate that such models need to be improved in order to address extreme rainfall events.