In this project, the P.I.'s will investigate numerical methods leading to development of improved global ocean models suitable for climate studies. Enhancements will be added to a primitive equation model and a filtered model (both developed by the P.I. and collaborators). Major focus will be on : 1. Domain decomposition strategies and boundary-fitted coordinates to add boundary layers with higher order physics; 2. Conservation properties of efficient finite difference schemes; 3. Composite overlapping grid techniques for embedding the mixed layer in the larger models; and 4. Comparison of the PE model with tropical Atlantic data.