Large scale integrated hydrological modelling of the impact of climate change on the water balance with DANUBIA

摘要

Future climate change will affect the water availability in large areas. Inorder to derive appropriate adaptation strategies the impact on the waterbalance has to be determined on a regional scale in a high spatial andtemporal resolution. Within the framework of the BRAHMATWINN project themodel system DANUBIA, developed within the project GLOWA Danube (GLOWADanube, 2010; Mauser and Ludwig, 2002), was applied to calculate the waterbalance components under past and future climate conditions in thelarge-scale mountain watersheds of the Upper Danube and the UpperBrahmaputra. To use CLM model output data as meteorological drivers DANUBIAis coupled with the scaling tool SCALMET (Marke, 2008). For the determinationof the impact of glacier melt water on the water balance the model SURGES(Weber et al., 2008; Prasch, 2010) is integrated into DANUBIA. In thispaper we introduce the hydrological model DANUBIA with the tools SCALMET andSURGES. By means of the distributed hydrological time series for the pastfrom 1971 to 2000 the model performance is presented. In order to determinethe impact of climate change on the water balance in both catchments, timeseries from 2011 to 2080 according to the IPCC SRES emission scenarios A2,A1B, B2 and Commitment are analysed. Together with the socioeconomicoutcomes (see Chapter 4) the DANUBIA model results provide the basis for thederivation of Integrated Water Resources Management Strategies to adapt toclimate change impacts (see Chapter 9 and 10).