Resonant forcing of barotropic coastally trapped waves.

Abstract

The interaction of a longshore current with a longshore topographic feature was investigated in the barotropic case. It is shown that near resonance, when a long wave speed is close to zero there is enhanced generation of upstream and downstream coastally trapped waves. An evolution equation of the KdV type was derived to describe the resonant behaviour and numerical solutions are discussed for a range of parameters describing the forcing terms, the detuning term and dissipation. The analogous situation of resonant generation due to wind stress was developed in an appendix. (A)