Weak Reflection of Water Waves by Bottom Obstacles

Abstract

For a gradually varying bottom, an approximate theory is developed for the calculation of scattering properties of two-dimensional water waves. An integral representation is first formed with the help of a Green's function. An iterative solution is then obtained by using Rayleigh's wave shoaling equation as the first approximation. The reflection coefficient is found to depend on the smoothness of the obstacle; more abrupt depth changes at the ends cause stronger wave interference. For obstacles with a flat top it is found that under certain conditions only the sloping ends are responsible for wave scattering.