The evaluation of the potential of global data products for snow hydrological modelling in ungauged high-alpine catchments

Abstract. For many ungauged mountain regions, global datasets of different meteorological and land surface parameters are the only data sources available. However, their applicability in modelling high-alpine regions has been insufficiently investigated so far. Therefore, we tested a suite globally available by applying physically based Cold Regions Hydrological Model (CRHM) for 10-year (September 2000–August 2010) period gauged Research Catchment Zugspitze (RCZ), which is 12 km2 located European Alps. Besides data, snow depth measured at two stations. We ran CRHM with reference run situ-measured 2.5 m high-resolution digital elevation model (DEM) parameterization characteristics. Regarding setups, used 10 (including versions ERA, GLDAS, CFSR, CHIRPS) additionally one transferred dataset from similar station vicinity. DEMs, ALOS (Advanced Land Observing Satellite) SRTM (Shuttle Radar Topography Mission) (both 30 m) as well GTOPO30 (1 km). The following main goals were investigated: (a) reliability simulations depth, specific hydrological runoff products (b) influence DEMs on such topographically complex terrain. range between all setups mean decadal temperature high 3.5 ?C precipitation sum 1510 mm, subsequently leads to large offsets results. Only three reference, situ CHIRPS dataset, substituting only, showed agreeable results when comparing modelled depth. Nevertheless, those obvious differences catchment's regime cover, ablation period, date, quantity maximum water equivalent entire catchment parts. All other performed worse. In contrast, DEM reproduced quite well. Differences occurred mainly due radiation input spatial realizations. Even though have same resolution, they considerable product origins. Despite fact that very coarse relatively mean, advise against using this heterogeneous terrain since small-scale topographic characteristics cannot be captured. While not suitable sound RCZ, choice resolutions decametre level less critical. can valuable source substitute single missing variables. future, however, expect an increasing role basins further improvements, refinements steps regarding assimilation remote sensing data.