The Field Distributions and Balances in a Baroclinic Annulus Wave

Abstract

The detailed structure of a steady wave occurring in a rotating annulus of square cross-section and having a free surface is presented. The field distributions are obtained by numerical integration of the three-dimensional nonlinear Navier-Stokes equations. The distributions of pressure, temperature, and the three velocity components are displayed for the total fields and for the fields of deviation from the zonal means. Their dynamical balances are also discussed. The deviation wave is a type of Eady wave and the solution is used to discuss the structure of such waves in finite amplitude steady-state form under the influence of variations in baroclinicity, shear, and boundary layers. The side layers make little contribution to the characteristics of the wave in the deviation field although significant Ekman layer features do appear. The flow is essentially in hydrostatic and geostrophic balance except in the boundary layers. Heat conduction is important only in the side layers.