Storm-Forced Near-Inertial Waves on a Beta Plane

Abstract

The influence of the beta effect, that is, the variation of the Coriolis parameter with latitude on the energy flux from moving storms to the oceanic internal wave field is considered. Large-scale, fast-moving storms are emphasized, and the oceanic internal wave field is considered. Large-scale, fast-moving storms are emphasized, and the oceanic response is described as forced inertial oscillations on a beta plane. An analytical solution to the energy flux is obtained and discussed for a simple wind stress field. The beta effect introduces a difference between westward and eastward moving storms. It is most pronounced for storm speeds that move the storms past a fixed point in about an inertial period. In this regime, the energy flux to the internal wave field is, relative to the f-plane case, increased when the storm moves eastward and decreased when it moves westward. However, the influence of the beta effect on the energy flux to the internal wave field is generally small, and the f-plane approximation is expected to give a good description of the energy flux.