Oceanic Horizontal Random Temperature Structure.

Abstract : A theoretical model of the horizontal spatial distribution of thermal microstructure is developed for anisotropic turbulence. A two-term power law representation for buoyancy and convective forces is applicable for wavenumbers greater than those of the internal wave field, but less than those in the dissipation range. The model predicts a temperature power density spectrum which decays as -5/3 and -3 in the convective and buoyancy ranges, respectively. The relative power in the two ranges is a function of depth and depends on the total rate of energy dissipation, the total rate of dissipation of temperature variance, and the Brunt-Vaisala frequency. Companion experimental data from 54 long horizontal tows at depths between 97.5 and 1454 m at two widely separated stations in the Bermuda area of the North Atlantic verify the theoretical predictions. (Author)