HR: 10:20h
AN: H42B-01    [Abstracts]
TI: Rocks and Rain: orographic precipitation and the form of mountain ranges
AU: * Roe, G H
EM: gerard@ess.washington.edu
AF: Department of Earth and Space Sciences, University of Washington Condon Hall, Seattle, Wa 98195 United States
AU: Anders, A M
EM: anders@u.washington.edu
AF: Department of Earth and Space Sciences, University of Washington Condon Hall, Seattle, Wa 98195 United States
AU: Durran, D R
EM: durrand@atmos.washington.edu
AF: Department of Earth and Space Sciences, University of Washington Condon Hall, Seattle, Wa 98195 United States
AU: Durran, D R
EM: durrand@atmos.washington.edu
AF: Department of Atmospheric Sciences, University of Washington ATG, Seattle, Wa 98195 United States
AU: Montgomery, D R
EM: dave@ess.washington.edu
AF: Department of Earth and Space Sciences, University of Washington Condon Hall, Seattle, Wa 98195 United States
AU: Hallet, B
EM: hallet@u.washington.edu
AF: Department of Earth and Space Sciences, University of Washington Condon Hall, Seattle, Wa 98195 United States
AB: In mountainous landscapes patterns of erosion reflect patterns of precipitation that are, in turn, controlled by the orography. Ultimately therefore, the feedbacks between orography and the climate it creates are responsible for the sculpting of mountain ranges. Key questions concerning these interactions are: 1) how robust are patterns of precipitation on geologic time scales? and 2) how do those patterns affect landscape form? Since climate is by definition the statistics of weather, there is tremendous information to be gleaned from how patterns of precipitation vary between different weather events. However up to now sparse measurements and computational limitations have hampered our knowledge of such variations. For the Olympics in Washington State, a characteristic midlatitude mountain range, we report results from a high-resolution, state-of-the-art numerical weather prediction model and a dense network of precipitation gauges. Down to scales around 10 km, the patterns of precipitation are remarkably robust both storm-by-storm and year-to-year, lending confidence that they are indeed persistent on the relevant time scales. Secondly, the consequences of the coupled interactions are presented using a landscape evolution model coupled with a simple model of orographic precipitation that is able to substantially reproduce the observed precipitation patterns.
DE: 1625 Geomorphology and weathering (0790, 1824, 1825, 1826, 1886)
DE: 1815 Erosion
DE: 1825 Geomorphology: fluvial (1625)
DE: 1854 Precipitation (3354)
SC: Hydrology [H]
MN: Fall Meeting 2005