The main goal of this project is to develop a state-of-the-art data assimilation system that incorporates near-realtime data with which we can provide the community a high quality ocean state product. This assimilation system consists of an Ensemble Filter applied to GFDL's second generation fully coupled climate model (CM2.1, Delworth et al. [2006]). The ocean component of the coupled data assimilation (CDA) is the fourth version of the Modular Ocean Model (MOM4, Griffies et al. [2004]) configured with 50 vertical levels (22 levels of 10-m thickness each in the top 220 m) and 1° horizontal B-grid resolution, telescoping to 1/3° meridional spacing by 1° near the equator.