Developments in Ocean and Coupled Data Assimilation at NCEP

A Hybrid LETKF/3DVar ocean data assimilation (DA) system is currently being tested for operational implementation at NCEP. Applications include: (1) a climate-scale global ocean data assimilation system (Hybrid-GODAS) using GFDL's MOM6 ocean model to replace the operational 3DVar-GODAS using MOM3, (2) initialization of the HYCOM ocean model for hurricane prediction using the coupled HYCOM/HWRF, (3) strongly coupled data assimilation between the ocean and atmosphere, (4) initialization of sea-ice coupled with the ocean, and (5) initialization of wave models. A number of new observational datasets are being included into the data assimialtion, both satellite and in situ. The Hybrid-Gain DA method will be described, along with the strong coupling approach, and the specific details of incorporating the new observational data into these DA systems.