Medium Scale Morphodynamics of the Central Dithmarschen Bight

The morphology of the tidal flat area of the central Dithmarschen Bight in the German Wadden Sea is highly dynamic. The high tidal range, the exposure to waves and the abundantly available fine sediments allow for large morphological changes. The complex bathymetry causes a strongly varying significance of the dominating processes. The importance of these processes for the observed dynamics has been investigated on a medium scale. A time scale of approximately one decade and a spatial scale in the order of kilometres have been considered. The analysis of extensive field data has been combined with the application of a process-based numerical model. Input filtering techniques have been applied and evaluated to enable morphodynamic simulations over ten year periods. In the calibration and validation volumetric comparisons to the field data have been made. It is shown that the model is capable of reproducing the medium scale morphodynamics in a good manner. Through application of the validated model the significance of the driving forces for several sub-domains has been investigated. Relationships between the observed morphodynamics and the underlying processes could be determined. Furthermore, the results of a model prediction of the morphological changes over ten years are presented.