Abstract

Dune and berm erosion is a critical shoreline process that has economic, environmental and public safety impacts. Accurate prediction of beach erosion through numerical modeling is key in formulating solutions to this problem, but this has proven difficult. This study attempts to combine data and numerical models in order to improve our predictive capabilities of beach and dune erosion. The data for the model comes from two separate dune erosion experiments. The first, performed in this study, was a small-scale effort to analyze the effect of berm and dune geometry on time-dependent erosion during a simulated storm. The second was a large-scale experiment performed by van Gent et al. (2006), which tested the relationship between wave period and dune erosion. An existing combined wave and current model was modified to drive a sediment transport model based on simple equations for cross-shore and long-shore transport. The model predictions of erosion were within a factor of 2 error of the experimental measurements. The model was then used to calculate berm and dune erosion for obliquely incident waves and found that decreasing the angle of incidence of the waves does not necessarily increase dune erosion.