Quantifying Antarctic deep waters in SODA reanalysis product

Abstract

The Antarctic intermediate and deep water masses present in the Atlantic sector of the Southern Ocean were quantified through the inverse method known as Optimum Multiparameter (OMP) analysis. The method was applied to the Simple Ocean Data Assimilation (SODA) product, which assimilates real observed ocean data into a hydrodynamic model. Results here show that the SODA dataset is able to capture reasonably well the intermediate and deep water mass (i.e. Warm Deep Water, Weddell Sea Deep Water, Weddell Sea Bottom Water, and Circumpolar Deep Water) regional distribution and contribution to the total mixture in the Weddell Sea and Weddell-Scotia Confluence. Those regions are, respectively, the main Antarctic Bottom Water source and export areas to the global ocean. We infer some aspects of the ocean circulation from the water mass distribution obtained. However, some efforts are still needed to better represent the deep salinity in these areas. The weak representation of this hydrographic parameter could be associated with the model’s lack of important cryospheric processes directly involved with bottom water formation.