Evaluation of single waves effects on the morphology evolution of a coastal lagoon inlet

Abstract

In morphodynamic simulations of coastal lagoons should be included the several processes that contribute to sediment transport and consequently to bathymetric cha nges. The individual contribution of the tidal currents, waves, wind and rivers disc harge should be considered to better characterize the study area evolution. In the work presented herein, an evaluation of single wave effects on the bathymetric changes of a coastal inlet is presented, by neglecting the forcing of wind and rivers discharge in the numerical simulations and filtering the changes produced by the tidal currents. The bathymet ric changes, the residual sediment fluxes and the sedimentation rates induced by eight monochromatic waves at the inlet were analyzed. It was concluded that the influence of the simulated waves on the morphodynamics is restricted to the inlet and adjacent nearshore. Additionally, the changes in the bathymetry and residual sediment transport are strongly dependent on the wave height forcing rather than on their frequency of occurrence. These conclusions emphasize the importance of independently analyze each wave, to better understand its impact in coastal systems dynamics.