A MULTIVARIATE STATISTICAL MODEL FOR ADVANCED STORM SURGE ANALYSES IN THE NORTH SEA

Thomas Wahl, Jürgen Jensen, Christoph Mudersbach

Abstract


The knowledge of the characteristics of possible storm surges is essential to perform integrated risk analyses, e.g. based on the source-pathway-receptor concept, including the storm surge analyses (source), modeling failure mechanisms of the flood protection measures (pathway) and the quantification of potential losses (receptor). Focusing on the source part, a stochastic storm surge generator for the south-eastern North Sea is presented. The input data for the model are high resolution sea level observations from tide gauges during extreme events. Followed by the parameterization and fitting parametric distribution functions to the data sets, Monte-Carlo-Simulations allow the reconstruction of a large number of synthetic storm surge events. The latter serve as input data for the risk analyses and contribute to improving the overall results. The occurrence probabilities of the simulated extreme events are estimated based on multivariate statistics considering Copula functions, accounting for the structure of dependence overlooking the margins.

Keywords


integrated risk analyses; stochastic storm surge simulation; multivariate statistics; Copula model

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