Global and regional ocean thermal analysis systems at Fleet Numerical Meteorology and Oceanography Center

The Optimum Thermal Interpolation System (OTIS) Version 4.0 has been implemented at Fleet Numerical Meteorology and Oceanography Center (FNMOC). OTIS is an optimum interpolation based data assimilation scheme that makes full use of the real-time observational data base available at FNMOC. OTIS also utilizes a real-time “ocean bogus” data base describing the surface positions and characteristics of ocean fronts and eddies. OTIS 4.0 routinely produces eddy resolving, surface to bottom regional analyses of temperature and salinity once per day, and global SST analyses twice per day. This paper gives a brief description of the OTIS analysis scheme with particular emphasis given to the generation of synthetic temperature observations in the regional analyses