Modelling directional random wave propagation inshore

Abstract

Long-term nearshore wave climate prediction requires an efficient solution method for the propagation of directional random waves from offshore. Predictions of laboratory data for waves over submerged shoals indicate that waves with broad, but not narrow, directional spread are well predicted without taking diffraction into account, and an efficient parabolic, ‘ray-tracing’ solver may thus be used. Application to the complex coastal bathymetry off East Anglia indicates that inshore wave climate is generally only slightly affected by the degree of directionality, tidal currents, and wind forcing over the propagation region. It thus seems realistic to define inshore wave climate for a range of offshore conditions, defined only by wave height, period and direction, and of course tidal level, using an efficient parabolic solver.