Internal waves in the upper ocean.

Abstract

Previous work has shown that the deep-ocean internal-wave field has little variability and can be described by a stationary spectrum. This analysis of upper-ocean internal-wave data supports the hypothesis that the variable upper-ocean (within the upper 200 m) internal-wave field can be represented as fluctuations superimposed on the base-state stionary spectrum, such as that given by the model of Garrett and Munk. The parameters of the Garrett-Munk model are particularized by a best fit to the deep-ocean IWEX data; the model is then directly compared to upper ocean internal-wave data from Cape Cod, FLIP, GATE, St. Croix, and the NRL towed chain. These data, properly interpreted line-sensor data, and the existence of a dynamic saturation mechanism are all consistent with the hypothesis. (A)