Assimilation of Oceanographic and Satellite Data by the NEMO Ocean Circulation Model Using the Ensemble Kalman Filter

The paper presents results of applying an oceanographic data assimilation system (ODAS) for assessing the state of hydrophysical fields of the World Ocean. The assimilation is performed with the one-degree NEMO model using the ensemble Kalman filter LETKF. The study used data from Argo profiling floats on the vertical distribution of temperature and water salinity and gridded data on sea surface temperature, sea ice concentration, and satellite altimetry. It is shown that the system successfully reproduces three-dimensional temperature and salinity fields and the variability of the sea level surface. The simulation of sea ice characteristics improves insignificantly as compared to other characteristics.