SWAN hindcast in the Eastern Wadden Sea and Eems-Dollard estuary : storm of 9 November 2007

A hindcast study has been performed with the SWAN model in the Eastern Wadden Sea of the 9 November 2007 storm. The water level and current fields were computed using a two-coupled Delft3D-SWAN model. The results of the wave model were compared to measurements obtained by four directional wave rider buoys. One buoy was located in the main tidal channel to the Eems-Dollard estuary and three buoys were located of the shallow tidal flats close to the mainland dikes. The SWAN model results show that the tidal inlets block most of the North Sea waves. The results show a systematic under-prediction of low-frequency wave energy by SWAN. The wind sea part of the spectrum is reasonably well predicted. Wave heights are under-estimated in depth-limited situations. Currents affect the wave conditions in the tidal channels but they do not improve the performance of SWAN at the buoy location. Mud-induced dissipation plays a small damping role in these areas. This study confirms that SWAN requires improvements with respect to the prediction of low-frequency storm-waves in the Eastern Wadden Sea and with respect to the prediction of wave conditions in depth-limited situations.