Internal Wave Reflection by a Velocity Shear and Density Anomaly

Abstract

Numerical solutions are obtained for the reflection of upward propagating internal waves by simple pycnocline and current shear models. Results for a simple monotonic shear and a velocity jet, with and without a pycnocline, lead to the conclusions that: 1) significant portions of an internal wave spectrum generated in the deep ocean can be reflected back downward by changing Brunt-Väisälä frequency and shear, even in situations not involving critical layers; 2) reflections by shear usually reinforce those from density variations; and 3) under some propagation conditions, a portion of the wave energy is leaked through the velocity jet, even when the fluid within the jet will not support wave motion of the impinging, frequency.