Baroclinic Instabilities of A Deep Fluid. Part II

Abstract

Numerical computations are conducted to investigate the deep-fluid effects on the baroclinically unstable waves whose nondimensional wavenumbers are of order unity[k?O(1),llsim;(1)]. Two representative values of the Richardson number, Ri=0.5 and Ri=2.0, are used in the actual computations. The mass-divergence effect appears to reduce principally the propagation speed and, to a degree, the growth rate in both instability regimes. In particular, the mass-divergence effect affects the wave structure of the vertical velocity, shifting the vertical level of Wmax. Also, the latitudinal wavenumber dependence of the eigenvalue is examined.