Southern Ocean Freshwater (SO-FRESH)

• Project by: Alessandro Silvano
• December 15, 2024

Dr. Alessandro Silvano, visiting scientist, March 2024 – August 2024

The Southern Ocean Freshwater project aims to understand changes in freshwater fluxes into the Southern Ocean. This project has developed a new regional product of satellite-derived (based on SMOS) Sea Surface Salinity (SSS). This product is able to capture seasonal and interannual SSS variability between 2011 and 2023. By combining these SSS observations with other satellite products of sea ice concentration, sea surface temperature as well as in situ and modelling data, this project allows to relate surface salinity changes to freshwater fluxes associated with sea ice, precipitation and the ocean itself (by upwelling of salty water for example).

The results highlight a seasonal signal (Fig. 1) of increased (decreased) SSS during period of sea ice formation (melting) in austral winter (summer). The interannual signals suggest an increase in salinity over the last years of the time series. Ongoing analysis based on work developed at science hub of ESA-ESRIN is trying to understand the drivers of such changes and how they are related to the recent decline in Antarctic sea ice coverage.