Impact of spatial resolution on the hydrological simulation of the Durance high-Alpine catchment, France

Abstract

The water balance of the mountainous Durance river catchment, French Alps, is simulated from 1981 to 1994 with a soil-vegetation-atmosphere transfer (SVAT) model. Particular attention is paid to the snow-cover evolution using a detailed model of the snowpack evolution. The results are validated by comparison of the simulated discharges calculated by the SVAT with daily observations at three gauging stations located in the water-shed. Three different spatial resolutions are used (1, 8 and 46 km) in order to evaluate the impact on the surface-water-budget results. Comparison with the finest resolution indicates the need for sub-grid-scale parameterization for the model with larger resolution.