17 - Shallow water wave modelling in the nearshore (SWAN)

Abstract

Knowledge of the state of the sea is crucial for the development of economic, military and tourist activities. Furthermore, adequate management of extreme high-energy events and their impacts on the coast requires an understanding of wave processes. Wind and wave characteristics are often available in the open ocean. However, waves in shallow water experience changes (e.g. refraction, diffraction and wave breaking) that are not only different from deep water but also difficult to measure. Nearshore wave models help to predict the evolution of the wind-generated waves by using numerical approaches to translate offshore conditions in shallower coastal environments. SWAN is an open source spectral nearshore wave model (phase-averaged model) for simulating and propagating waves from deep water to the nearshore. Based on the action balance equation, it accounts for wave growth by wind, the interaction between individual waves and the dissipation and decay by wave breaking and bottom friction.