The Cryosphere Discussions www.the-cryosphere-discuss.net 1994-0432 1994-0440 2 4 2008 10.5194/tcd-2-513-2008 http://www.the-cryosphere-discuss.net/2/513/2008/ http://www.the-cryosphere-discuss.net/2/513/2008/tcd-2-513-2008.html http://www.the-cryosphere-discuss.net/2/513/2008/tcd-2-513-2008.pdf 513 556 2008-07-11 High resolution modelling of snow transport in complex terrain using simulated wind fields M. Bernhardt m.bernhardt@iggf.geo.uni-muenchen.de U. Strasser G. E. Liston W. Mauser Department for Earth and Environmental Sciences, Ludwig-Maximilians-University (LMU), Munich, Germany Cooperative Inst. for Research in the Atmosphere, Colorado State Univ., Fort Collins, USA Snow transport is one of the most dominant processes influencing the snow cover accumulation and ablation in high alpine mountain environments. Hence, the spatial and temporal variability of the snow cover is significantly modified with respective consequences on the total amount of water in the snow pack, on the temporal dynamics of the runoff and on the energy balance of the surface. For the presented study we used the snow transport model SnowTran-3D in combination with MM5 (Penn State University – National Center for Atmospheric Research MM5 model) generated wind fields. In a first step the MM5 wind fields were downscaled by using a semi-empirical approach which accounts for the elevation difference of model and real topography, as well as aspect, inclination and vegetation. The target resolution of 30 m corresponds to the resolution of the best available DEM and land cover map. For the numerical modelling, data of six automatic meteorological stations were used, comprising the winter season (September–August) of 2003/04 and 2004/05. 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