Advances in Geosciences www.adv-geosci.net 1680-7340 1680-7359 12 Mediterranean storms and extreme events in an era of climate change 2007 10.5194/adgeo-12-43-2007 http://www.adv-geosci.net/12/43/2007/ http://www.adv-geosci.net/12/43/2007/adgeo-12-43-2007.html http://www.adv-geosci.net/12/43/2007/adgeo-12-43-2007.pdf 43 50 2007-07-02 Probability estimates of heavy precipitation events in a flood-prone central-European region with enhanced influence of Mediterranean cyclones J. Kysely kysely@ufa.cas.cz J. Picek Institute of Atmospheric Physics AS CR, Prague, Czech Republic Technical University, Liberec, Czech Republic Due to synoptic-climatological reasons as well as a specific configuration of mountain ranges, the northeast part of the Czech Republic is an area with an enhanced influence of low-pressure systems of the Mediterranean origin. They are associated with an upper-level advection of warm and moist air and often lead to heavy precipitation events. Particularities of this area are evaluated using a regional frequency analysis. The northeast region is identified as a homogeneous one according to tests on statistical characteristics of precipitation extremes (annual maxima of 1- to 7-day amounts), and observed distributions follow a different model compared to the surrounding area. Noteworthy is the heavy tail of distributions of multi-day events, reflected also in inapplicability of the L-moment estimators for the general 4-parameter kappa distribution utilized in Monte Carlo simulations in regional homogeneity and goodness-of-fit tests. We overcome this issue by using the maximum likelihood estimation. The Generalized Logistic distribution is identified as the most suitable one for modelling annual maxima; advantages of the regional over local approach to the frequency analysis consist mainly in reduced uncertainty of the growth curves and design value estimates. 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