On the role of topography and wind stress on the stability of the thermohaline circulation

A frictional geostrophic model is used to examine how the stability of the thermo haline circulation is a ected by idealized topographic variations and the presence or absence of wind stress If the ow exhibits collapses we consider how topography and wind stress a ect the ensuing oscillations Large scale slope up towards the north or the west can signi cantly destabilize the circulation by modifying the barotropic ow and reducing the depth of convection Wind stress stabilizes the circulation by deep ening the thermocline in the subtropical gyre Wind driving can also radically reduce the period of oscillations by destabilizing the northern halocline in the collapsed phase The overall period of the oscillation is usually governed by the time taken for di usive warming to destabilize the deep ocean