A Numerical Model to Simulate Beach and Dune Evolution

A numerical model to simulate cross-shore (CS) beach and dune evolution induced by storms was developed in this study. The model development was partly based on previous CS modeling work in which modules describing the response of the beach profile in the offshore, surf, and swash zone were described in detail, but where the dune module is lacking. The dune module, adopting wave impact theory, was integrated into the previous model to complete a new numerical model. To calibrate and validate the new model, high-quality data on hydrodynamics and dune profile response from both laboratory and field data were used. The laboratory data included two experimental cases related to dune erosion from the SUPERTANK data collection project, whereas the field data consisted of two cases from Ocean City, Maryland and one case from Myrtle Beach, South Carolina. Overall, good agreement was obtained between calculations and measurements, illustrating that the model is reliable and robust in simulating beach and dune evolution. However, the poststorm beach recovery in the swash zone could not be well captured by this model. Thus, in subsequent model development, onshore transport and accretion in the nearshore will be emphasized to simulate long-term beach evolution.