Salt Wedge Intrusion and Stokes Drift

Abstract

This paper describes the influence of surface waves on salt-wedge intrusion in terms of radiation stress. Radiation stress which includes Stokes drift effect may increase salt-wedge intrusion when surface waves propagate up a river. This study thus aims to reveal the effect of radiation stress on the distance of salt-wedge intrusion by fully nonlinear strongly dispersive internal wave equations and three-dimensional numerical computation model, Fantom3D. Fully nonlinear strongly dispersive internal wave model reveals the possibility that large radiation stress is induced near the river mouth and increases the distance of salt-wedge intrusion. Three-dimensional numerical model also demonstrates that there is a significant difference in the intrusion distance by taking into account radiation stress.