Bench-mark morphodynamic model Ameland Inlet

The bench-mark study specifically aims to identify which trends and patterns in morphodynamic behaviour can or can't be reproduced. The model results presented in the bench-mark simulation show that morphodynamically stable simulations over a timescale of 5 to 10 years can be obtained with Delft3D. The use of a parallel online approach, in combination with a low-resolution model grid, allows us to run with acceptable computational times. A qualitative comparison of bed-levels reveals a major short-coming of the bench-mark model. The modelled morphodynamic response overpredicts the measured changes of the ebb-tidal delta; the ebb-tidal delta develops beyond observed limits. However, the comparison of the observed trends shows, in the bench-mark simulation and all sensitivity tests, that the model is capable of reproducing the dominant trends. Conceptual descriptions show that wave-dominated ebb-tidal deltas tend to be pushed closer to the inlet throat. In the model, it is likely that the balance between the offshore directed tidal component, and the onshore directed wave-driven transports is not resolved accurately enough. By selecting a highly efficient bench-mark model we can easily implement, test and verify new insights, model developments and advances as these are obtained in the Kustgenese 2.0 project.