SPECTRAL MODEL FOR WAVE TRANSFORMATION AND BREAKING OVER IRREGULAR BATHYMETRY

A numerical model is presented that predicts the evolution of a direct ional spectral sea state over a varying bathymetry using superposition of results of a parabolic monochromatic wave model run for each initi al frequency-direction component. The model predicts dissipation due t o wave breaking using a statistical breaking model and has been tested with existing data for unidirectional random waves breaking over a pl ane beach. Experiments were also conducted for a series of random dire ctional waves breaking over a circular shoal to test the model in a tw o-dimensional wave field. The model performs well in both cases, altho ugh directional effects are not included in the breaking dissipation f ormulation.