The equatorial meandering of abyssal ocean currents

Abstract

Numerical simulations of the nonlinear primitive equations show that meridionally-flowing western-boundary grounded abyssal ocean currents, which are in a planetary-geostrophic dynamical balance in midlatitudes, become increasingly nonlinear and turn eastward as they approach the tropics developing into a meandering stationary planetary wave structure as they flow along the equator. A distinguished steady-state nonlinear dynamical asymptotic theory is introduced into the equatorial -plane shallow water equations that describes the nonlinear stationary equatorial wave structure.