Analytical Representation of Internal Wave Spectra

Abstract

Analytical expressions of internal wave spectra (and coherences) are presented, based on a variant of the Garrett and Munk (1975) model. The change is from a slope of ?2.5 to ?2 in wavenumber spectra, as suggested by recent measurements. This proves convenient analytically. The final results depend on one ocean parameter n/f, the ratio of buoyancy to inertial frequency; and two model parameters corresponding to energy level and bandwidth. There is no need to assume an exponential dependence of the buoyancy frequency with depth. The properties of coherence measured along characteristics are also discussed.