Advances in Geosciences www.adv-geosci.net 1680-7340 1680-7359 26 11th EGU Plinius Conference on Mediterranean Storms (2009) 2010 10.5194/adgeo-26-39-2010 http://www.adv-geosci.net/26/39/2010/ http://www.adv-geosci.net/26/39/2010/adgeo-26-39-2010.html http://www.adv-geosci.net/26/39/2010/adgeo-26-39-2010.pdf 39 44 2010-07-02 Precipitation downscaling using random cascades: a case study in Italy B. Groppelli bibiana.groppelli@polimi.it D. Bocchiola R. Rosso Politecnico di Milano, Milano, Italy We present a Stochastic Space Random Cascade (SSRC) approach to downscale precipitation from a Global Climate Model (hereon, <i>GCM</i>s) for an Italian Alpine watershed, the Oglio river (1440 km²). The SSRC model is locally tuned upon Oglio river for spatial downscaling (approx. 2 km) of daily precipitation from the NCAR Parallel Climate Model. We use a 10 years (1990–1999) series of observed daily precipitation data from 25 rain gages. 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