The Resonant Interaction between a Long Internal Gravity Wave and a Surface Gravity Wave Packet

Abstract

The long-short wave interactions between an internal gravity wave and a surface gravity wave packet in a two-layer fluid are investigated. When the phase speed of the internal wave coincides with the group velocity of the surface wave packet, a strong interaction occurs. The equations describing this interaction are derived both for a shallow (in comparison with a length scale of the long wave) fluid layer and for a deep one, and are studied numerically.