APPLICATION OF A GENERALIZED TOPMODEL TO THE SMALL RINGELBACH CATCHMENT, VOSGES, FRANCE

This paper describes the application of the revised parabolic transmis sivity profile form of TOPMODEL, leading to a second-order hyperbolic base flow recession curve, to four years of 18 minute data from the 36 ha Ringelbach research catchment in the Vosges, France. The model is completed by evapotranspiration, snowmelt and runoff routing component s. As far as possible the parameters of this form of the model, or the ir ranges, are estimated a priori. Results are given that compare the original and revised forms of TOPMODEL, with and without optimization. One particular feature of this catchment is the availability of measu rements of saturated areas. These are taken into account by using a mo dified distribution of the soil-topographic index, in a first attempt to relax the assumption of uniform transmissivity in the catchment. It is shown that the reasonably good results obtained with the original model are improved with the revised model, particularly in the simulat ion of dry weather flows, and that further improvements are obtained w ith the modified soil-topographic index distribution.