This project is a continuation of Kawase's previous studies, on the effect of stratification and upper ocean circulation on the buoyancy-driven abyssal circulation. During the course of this program, the PI will: (1) perform experiments with a multi-layer numerical ocean circulation model under idealized conditions to study the effect of stratification and upper ocean circulation on the buoyancy driven abyssal circulation and, (2) develop a general circulation model of the subtropical South Atlantic based on the same model. This program is a contribution to the WOCE Deep Basin Experiment recently initiated in the South Atlantic.