CROSS-SHORE HYDRODYNAMICS AND PROFILE RESPONSE MODELING

The issue of hydrodynamics causing cross-shore sediment transport is e xamined analytically. Undertow is represented based on recent experime ntal evidence. A relatively complete physics-based cross-shore sedimen t transport model, including mechanisms for suspended and bedload tran sport, is developed with the capacity for onshore and offshore transpo rt. Effects of turbulence, momentum transfer, and augmented volumetric flux in the surf zone, horizontal wave asymmetry, bottom boundary lay er, intermittent suspension, overtopping water levels, and gravity are included. The model is tested against data from laboratory experiment s involving regular and irregular waves, and overtopping conditions; i t is fairly successful in predicting prominent patterns of erosion and deposition, sediment overwash, and longshore bars. The model lacks lo ng-term stability.