Studying the Rhine basin with SIMGRO : impact of climate and land use changes on discharge and hydrological droughts

In this study we applied the hydrological model SIMGRO to the Rhine basin. After the input data of the model was improved, the simulated discharges at Lobith were very close to the measured discharges. The model was then used to study droughts and the impact of climate and land use changes on discharges in the Rhine basin. We used the KNMI’06 climate scenarios to examine the changes in discharge and droughts. Furthermore extreme changes in land use were analysed, e.g. all cropland to grass and all cropland to forest. The results from the different scenarios show that climate change has a much larger impact on discharges and droughts than extreme changes in land use. In the last part of the study for the Neckar basin the spatial distribution of droughts in surface and ground water were explored. The discharge of the Neckar basin reacts immediately on precipitation, so as well the occurrence of droughts