Advances in Geosciences www.adv-geosci.net 1680-7340 1680-7359 16 Observation, Prediction and Verification of Precipitation (EGU Session 2007) 2008 10.5194/adgeo-16-3-2008 http://www.adv-geosci.net/16/3/2008/ http://www.adv-geosci.net/16/3/2008/adgeo-16-3-2008.html http://www.adv-geosci.net/16/3/2008/adgeo-16-3-2008.pdf 3 9 2008-04-09 A multiscale approach for precipitation verification applied to the FORALPS case studies A. Lanciani S. Mariani M. Casaioli C. Accadia N. Tartaglione Inter-Universities National Consortium for Physics of Atmospheres and Hydrospheres (CINFAI), Camerino, Italy Agency for Environmental Protection and Technical Services (APAT), Rome, Italy Mathematics Department, University of Ferrara, Ferrara, Italy EUMETSAT, Darmstadt, Germany Physics Department, University of Camerino, Camerino, Italy Multiscale methods, such as the power spectrum, are suitable diagnostic tools for studying the second order statistics of a gridded field. For instance, in the case of Numerical Weather Prediction models, a drop in the power spectrum for a given scale indicates the inability of the model to reproduce the variance of the phenomenon below the correspondent spatial scale. Hence, these statistics provide an insight into the real resolution of a gridded field and must be accurately known for interpolation and downscaling purposes. In this work, belonging to the EU INTERREG IIIB Alpine Space FORALPS project, the power spectra of the precipitation fields for two intense rain events, which occurred over the north-eastern alpine region, have been studied in detail. A drop in the power spectrum at the shortest scales (about 30 km) has been found, as well as a strong matching between the precipitation spectrum and the spectrum of the orography. 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