全球智库信息集成服务系统

Ocean reanalyses are data assimilative simulations designed for a wide range of climate applications and downstream applications. An eddy-permitting global ocean reanalysis system is in continuous development at CMCC and we describe here the configuration of the reanalysis system (version 3.1) recently used to produce an ocean reanalysis for the altimetry era (1993-2011), which was released in December 2013. The system includes i) a three-dimensional variational analysis system able to assimilate all the in-situ observations of temperature and salinity along with altimetry data and ii) a weekly model integration performed by the NEMO ocean model coupled with the LIM2 sea-ice model and forced by the ERA-Interim atmospheric reanalysis. We detail the configuration of both the components. The validation results performed in a coordinated way are summarized in the paper, and suggest that the overall performance of the reanalysis is satisfactory, while a few problems linked to the sea-ice concentration minima and the sea level data assimilation still remain and are being improved for the next release.