Geostrophic Turbulence

Abstract

A theory is presented for the spectra of horizontal velocity and temperature at high wavenumbers in three-dimensional quasi-geostrophic flow. The theory predicts a minus third power dependence on both the horizontal and vertical wavenumbers for the spectra of both the kinetic energy and the temperature variance, with amplitudes determined by the pseudo-potential vorticity transfer function. It also predicts equipartition among the components of kinetic energy and available potential energy. Comparisons of the predicted with the observed spectra of kinetic energy and temperature are cited. There is approximate agreement, notably in the prediction of equipartition.