Geostrophic flow disturbances influenced by inhomogeneities of gravity field: 3D analytical model

Abstract

A theoretical problem on linear stationary disturbances introduced by spatial inhomogeneities of gravity field into the background geostrophic flow of the stratified rotating medium (atmosphere) is considered. For the first time, the three-dimensional analytical model is considered. Our results imply that inhomogeneities of the gravity field can lead to ordered perturbations of the velocity field of atmospheric currents in large areas. Our three-dimensional model allows us to understand and analyse some of the simplest mechanisms and patterns of generation of such disturbances and to make some estimates. The amplitude of the disturbances for the velocity horizontal components can reach values of the order of buoyancy frequency multiplied by the amplitude of deviations of the geoid. This result agrees with the estimates obtained previously for a substantially different disturbances mechanism caused by gravity field inhomogeneities.