TY  - JOUR
AU  - Stoll, S.
AU  - Hendricks-Franssen, H.J.
AU  - Butts, M.
AU  - Kinzelbach, W.
TI  - Analysis of the impact of climate change on groundwater related hydrological fluxes: a multi-model approach including different downscaling methods
JO  - Hydrology and earth system sciences
VL  - 15
SN  - 1027-5606
CY  - Katlenburg-Lindau
PB  - EGU
M1  - PreJuSER-15991
SP  - 21 - 38
PY  - 2011
N1  - We thank Henrik Madsen and Sara Lerer from DHI for their advice. The study was supported by SNF Project No. 200021_121862. The ENSEMBLES data used in this work was funded by the EU FP6 Integrated Project ENSEMBLES (Contract number 505539) whose support is gratefully acknowledged.
AB  - Climate change related modifications in the spatio-temporal distribution of precipitation and evapotranspiration will have an impact on groundwater resources. This study presents a modelling approach exploiting the advantages of integrated hydrological modelling and a broad climate model basis. We applied the integrated MIKE SHE model on a perialpine, small catchment in northern Switzerland near Zurich. To examine the impact of climate change we forced the hydrological model with data from eight GCM-RCM combinations showing systematic biases which are corrected by three different statistical downscaling methods, not only for precipitation but also for the variables that govern potential evapotranspiration. The downscaling methods are evaluated in a split sample test and the sensitivity of the downscaling procedure on the hydrological fluxes is analyzed. The RCMs resulted in very different projections of potential evapotranspiration and, especially, precipitation. All three downscaling methods reduced the differences between the predictions of the RCMs and all corrected predictions showed no future groundwater stress which can be related to an expected increase in precipitation during winter. It turned out that especially the timing of the precipitation and thus recharge is very important for the future development of the groundwater levels. However, the simulation experiments revealed the weaknesses of the downscaling methods which directly influence the predicted hydrological fluxes, and thus also the predicted groundwater levels. The downscaling process is identified as an important source of uncertainty in hydrological impact studies, which has to be accounted for. Therefore it is strongly recommended to test different downscaling methods by using verification data before applying them to climate model data.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000286723600003
DO  - DOI:10.5194/hess-15-21-2011
UR  - https://juser.fz-juelich.de/record/15991
ER  -