The role of baseflow in modelling low-flow processes in climate impact studies

Hydrological models do not yet appropriately represent the processes in catchments leading to low-flow situations. Further, the model-related parameters are strongly based on the present-day climate, so that the applicability of such models for water-resources planning under future climate conditions remains limited. This paper investigates the applicability of baseflow separation for improved model calibration that is relying more strongly on low-flow processes within catchments. Three different baseflow separation procedures were applied in 59 catchments in Switzerland. The results show that baseflow is physically determined and can be used to improve the performance of conceptual hydrological models. Thus, uncertainties in low-flow projections can be reduced.