This project is to study the three-dimensional structure of the wind-driven subtropical/subpolar ocean circulation using a numerical model. Using a density coordinate and ideal-fluid thermocline equations, the investigator will study the non- linear interactions between the ventilated thermocline and other aspects of the circulation. The model will enable the PI to obtain solutions for the three-dimensional structure of the wind- driven circulation in a continuously stratified ocean. The model will be applied to the North Atlantic region.