Application of the Alpine 3D model for glacier mass balance and glacier runoff studies at Goldbergkees, Austria

The model for mountain surface processes, Alpine 3D, was applied to the Goldbergkees basin (2.7 km(2), 52% glacierized) in the central Austrian Alps to model hourly discharge and glacier mass balance. Alpine 3D is a physically based model which focuses on snow-ice-soil energy and mass fluxes (without lateral, gravity driven flows) in rugged terrain. From the records of the Sonnblick observatory, located in the study area, a high-quality set of meteorological, glaciological and hydrological data could be provided to force and evaluate the model. A 1-year period was simulated starting from September 2004. The model results were evaluated using observations of the glacier mass balance and discharge at the catchment outlet. The spatial variation of modelled annual net mass balance of Goldbergkees shows good agreement to observed data. Significant deviations occur mainly at locations, which are presumably influenced by avalanche events or drifting snow. The quality of runoff simulation was estimated using the Nash-Sutcliffe model efficiency and the explained variance number. Both criteria demonstrate that the modelled catchment discharge is of satisfactory quality, despite the fact that the local mass balance is not well represented at all grid points. Copyright (c) 2008 John Wiley & Sons, Ltd.