期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2007
卷号：XXXVI-7/C50
出版社：Copernicus Publications
摘要：Representative real time information on snow depth and snow water equivalent is needed for several practical purposes, above all avalanche warning and flood forecast and control in spring. This study deals with snow depth and cover maps for updating the snow water equivalent simulated by an operational spatially distributed hydrological model. An evaluation of operational simulations of snow water equivalent and snow cover distribution for the winter season 2005/2006 will be presented for two Swiss basins. The simulations will be computed by adopting the real-time version of the PREVAH model (Precipitation Runoff EVApotranspiration HRU Model). PREVAH is currently implemented for flood forecast in the Linth basin (central Switzerland). Model simulations are compared to three sources of snow cover information: a) the operational Swiss wide snow depth map (1x1 km 2 resolution) based on a combination of snow depth ground observations from a dense measurement network and operational NOAA-AVHRR snow cover map. b) a NOAA-AVHRR sub- pixel snow-cover product (1x1 km 2 resolution) with estimation snow cover fraction at sub-pixel scale. c) an interpolated map of snow depth, estimated using information from stations close to the target area. Evaluations are performed by mean of categorical statistics. Results show, that the hydrological model is well able to provide reliable information on snow cover distribution. The accuracy with respect to the operational snow depth maps is always higher than 90%. The accuracy between the AVHRR snow cover maps and the model simulations is above 90% in the phase of snow accumulation until end of March and sinks below 80% during the ablation period
