On Coupling the Swan and Wam Wave Models for Accurate Nearshore Wave Predictions

Abstract

A simulation of wind-wave activity for the 1995 Hurricane Luis has been performed using the WAM and SWAN wave models. This study tested the WAM/SWAN interface option present in the SWAN code to determine the effectiveness of applying SWAN in the finest WAM nest as a means to obtain more accurate nearshore wave predictions. The SWAN code was developed specifically for the nearshore and contains formulations for two physical processes not represented in the WAM code: depth-induced wave breaking and triad wave-wave interaction. SWAN was run with and without these processes to determine their effects on the results. The inclusion of triad wave-wave interaction did not significantly affect the results. In contrast, the inclusion of depth-induced wave breaking reduced the maximum wave height at the storm's peak by 31% at the test site located 900 m offshore in a water depth of 8 m. These results suggest that applying the SWAN code in the finest WAM nest can be an effective means of obtaining more accurate nearshore wave predictions.