Selection of historical storms for atmospheric model validation

To comply with Dutch legal rules for the assessment of the safety level of water defences, the government funded program WTI (“Wettelijk Toets Instrumentarium”: legal assessment instruments) produces the required safety assessment instruments. This program is supported by the SBW (“Sterkte en Belastingen Waterkeringen”: strengths and loads of water defences) program, also funded by the government, which addresses relevant knowledge gaps. More details on the framework of SBW and the link with WTI, as well as motivation and background, are given in the report.

Within the SBW program, there is a project dealing with knowledge gaps in the determination of hydraulic loads that water defences should be able to withstand. This project, in turn, contains a wind modelling component dealing with the way in which extreme wind fields, used in the computations of extreme hydraulic load conditions, are determined. The first step of this recently started “SBW hydraulic loads wind modelling” project is the selection of a number of storms. These storms will be modelled subsequently and the modelling results will be validated using observations, so that choices can be made concerning appropriate models and methods of analysis. This report is devoted to the first step, the storm selection.