The water budget and the riverflows of the most important rivers over India have been simulated using ORCHIDEE (Organizing Carbon and Hydrology In Dynamic Ecosystems Environment) which is a Global Land Surface model including a river routing scheme. We have achieved the integration for the second year (1988) of the ISLSCP forcing data and we have performed a systematic comparison of the 2 years (1987, 1988) over the most important river basins of India.

In general, the 1988 flow is in good agreement with the observed monthly data from the GRDC database. The riverflow for 1987, a dry monsoon season, is usually underestimated. The simulated riverflow maximum is generally one or two months delayed compared to observations: this is possibly because we prescribe a time lag between runoff and discharge which is not adjusted for each basin. This will be improved in the next future. To be able to use more river discharge data, we will add, in the routing scheme, the computation of riverflow data at several locations added to the outlet.