On the multiple-cell thermohaline circulation

Abstract

The classic Stommel (1961) model of thermohaline circulation has predicted the existence of two modes of ocean motion for the pole-equator system. These are, one-cell thermal and one-cell saline modes. In contrast, the laboratory experiments conducted recently to duplicate this conceptual model have found three steady states in the control space of the model parameters: a two-layer thermal mode, a two-layer saline mode, and a three-layer hybrid state. A two-dimensional theoretical model is applied to investigate the multiple-cell formation. The lowest order solution is analysed using an expansion method and suggesting the aspect ratio as a small parameter. It is shown that asymmetry of vertical distribution between temperature and salinity is responsible for forming the multiple-cell thermohaline circulation.