Scattering of Rossby and Poincare waves off rough lateral boundaries

Abstract

Unified treatment of wave scattering from a rough boundary, which was originally developed by Nakayama et al. is presented. The stationary nature of the boundary process is used to show that the wave field is also stationary, and therefore can be represented by an Ito-Wiener-Hermite series. To study the reflection of Rossby and Poincare waves from continental edges is used. The presence of new, roughness-generated trapped waves is predicted in both cases. An incoming Rossby wave is shown to transfer energy to a set of Rossby waves with wavenumbers covering a wide range. In the case of Poincare wave scattering, a sink of energy exists at the coast which is attributed to the presence of a natural trapped mode, the Kelvin wave