HR: 10:50h
AN: H42B-03    [Abstracts]
TI: Tropical cyclone forcing of sediment transport in Taiwan
AU: * Galewsky, J
EM: galewsky@unm.edu
AF: Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131 United States
AU: Stark, C
EM: cstark@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory, Columbia University 61 Route 9W, Palisades, NY 10964 United States
AU: Dadson, S
EM: sjdad@ceh.ac.uk
AF: Centre for Ecology and Hydrology Wallingford, Maclean Building Crowmarsh Gifford, Wallingford, OX10 8BB United Kingdom
AU: Sobel, A
H42B-03 AF: Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10027 United States
AB: Erosion in mountain belts is commonly assumed to be jointly controlled by relief and annual mean precipitation. This assumption may be invalid in the Tropics, where much of the heavy rainfall is associated with tropical cyclones. Tropical cyclone rainfall is spatially and temporally intermittent and is dependent on topography in more complex ways than the storms that affect mid-latitude mountain belts. The links between tropical cyclone rainfall and landscape evolution in subtropical mountain belts are poorly understood. Here we use observations of precipitation and suspended sediment concentration from Taiwan along with numerical models of tropical cyclone dynamics to assess the links between tropical cyclone circulation, topography, precipitation, and sediment transport during Typhoons Herb (1996) and Toraji (2001). We show that (1) the sediment transport in the Kaoping River was driven by orographically enhanced tropical cyclone rainfall during both typhoons; (2) sediment transport in the Hualien River was controlled by tropical cyclone eyewall processes during Toraji; (3) sediment transport in the Choshui River, while largely controlled by coseismic effects of the 1999 Chichi earthquake, was enhanced by orographic effects during Toraji.
DE: 1815 Erosion
DE: 1817 Extreme events
DE: 1824 Geomorphology: general (1625)
DE: 1840 Hydrometeorology
DE: 1862 Sediment transport (4558)
SC: Hydrology [H]
MN: Fall Meeting 2005