This project is focused on the development and testing of ocean models to be used in coupled atmosphere-ocean climate models at the Goddard Institute for Space Studies (GISS) and also in stand-alone experiments to improve our understanding of, and ability to model climate change. Two general areas of the effort are: (1) the preparation of the Atmospheric Model E coupled to the HYCOM ocean model to be used in simulations of climate change for the Fifth Assessment Report of the Intergovernmental Panel on Climate Change; and (2) testing of the turbulence model in experiments with the GFDL MOM stand-alone ocean general circulation model (OGCM), and improvement of the turbulent mixing scheme and the representation of mesoscale eddies in the ocean mixed layer of the GISS coupled atmosphere-ocean climate model.