On the Dynamics of Long and Ultra-Long Waves in a Baroclinic Zonal Current

Abstract

A theoretical study of the dynamics of long and ultra-long waves in a baroclinic zonal current is made by the use of quasi-geostrophic and the characteristics difference approximation model. It of wave perturbations of the linearized structure. study of the dynamics of long and ultra-long waves in a baroclinic equations. The stability are iinvestigated perturbation is found that the wave solutions equations are classified numerically tonal of the tonal current with the finite applied to a multi-layer into three types : (i) a pair of amplifying and decaying waves, (ii) neutral waves without steering levels in the basic current and (iii) neutral waves with a steering accordance with their vertical disturbances, vertical of the vertical structure as well as of the phase velocity, is made in terms of the wavelength approximation multi-layer model. The energy conversion processes are discussed by making a comparison heat transport. between the unstable waves of the first mode and the higher mode. It is found that the maintenance of the unstable wave of the higher mode is only due to the increase of the eddy available potential energy caused by northward Finally a comparison between the characteristics of ultra-long waves obtained by the present study and those of the observation is made.