Hydrological modelling of the Saone Basin sensitivity to the soil model

In the framework of the GEWEX / Rhone project, which aims at developing a r egional model of the surface energy and water cycle in the Rhone basin, the flow of the Saone river basin (30000) km2 was modelled with the MARTHE mod el. The paper first describes the functionalities of MARTHE and then the mo delling of the Saone basin with a 2 km grid at a daily time step over a 14 years (August 1981 to July 1995) using different surface hydrological model s (soil models) : these soil models require from 3 to 91 parameters over th e entire basin. A comparison of the results shows that the daily flows at t he 52 gauging stations of the Saone are best modelled with the GR4 soil mod el using only 3 parameters. This advocates the gathering of additional data namely aquifer data and soil saturation in order to avoid over-parameteris ation. (C) 2001 Elsevier Science Ltd. All rights reserved.