Modeling waves in surfzones and around islands

A semi-empirical model for surf zone wave height decay is adapted to the parabolic equation method in order to include the effect of depth-limited wave breaking in combined refraction/diffraction calculations. Several examples for plane beaches are presented in order to show correspondence between the empirical model, its numerical formulation, and previous laboratory data. The model is then applied to the study of wave breaking and diffraction around offshore islands of various planforms. An analytic method for constant depth, which can be used to extend computed solutions to the farfield downwave of the island, is provided, and several simple examples treating the island as a finite width breakwater are examined.