The role of bathymetry, wave obliquity and coastal curvature in dune erosion prediction

This study aims at reducing uncertainty in dune erosion predictions, in particular at complex dune coasts, in order to improve the assessment method for dune safety against flooding. To that end, state-of-the-art process-based dune erosion models are employed to further investigate issues insufficiently covered by the current Dutch safety assessment method. The influence of cross-shore bathymetry, coastal curvature and incident wave angle are the main focus. With a 2DH XBeach model, it is shown that the interaction between cross-shore and alongshore processes is of major importance for wave obliquity and coastline curvature leading to dune erosion increased rates up to 30 to 50%. In addition, a Bayesian Network approach is introduced to create a practical framework for the inclusion of additional aspects and uncertainties to the safety assessment method for complex coasts