Meetings: Documents

Estimation of Fresh and Saltwater Fluxes and Transports in the Southern Ocean
[16-Dec-16] Ferster, B.S. and Subrahmanyam, B.
Presented at the 2016 AGU Fall Meeting
Since the 20th century, the Antarctic climate has been changing and relatively unstable. The Southern Ocean plays a major role in global ocean circulation. Because the Southern Ocean around Antarctica is the only location where the ocean can circulate freely all the way around the globe without continental barriers, it's a huge part of the ocean cycle. The use of salinity remote sensing technology offers spatial and temporal salinity observations than insitu and other conventional observations to better represent the sea surface salinity (SSS) in the Southern Ocean (SO). Using data sets from NASA’s Aquarius/SAC-D and ESA’s Soil Moisture and Ocean Salinity (SMOS), and NASA’s Soil Moisture Active and Passive (SMAP) we have estimated fresh and salt water fluxes. To address the issue of the satellites accuracy, this study validates Aquarius, SMOS and SMAP against Argo floats salinity data. Incorporating Ocean Surface Current Analyses Real-time (OSCAR) both zonal and meridional surface fresh and saltwater fluxes from the SO were calculated. We have compared Aquarius derived fluxes with SMOS, for the Aquarius time period, produced statistically similar zonal and meridional fresh and saltwater fluxes. This suggests the use of satellites within the SO can be used with confidence to monitor saline advection at higher frequencies and horizontal resolutions than the use of sparse in situ data of Argo in the SO. In addition to fluxes we have estimated integrated fresh and salt water transports using Simple Ocean Data Assimilation (SODA) reanalysis. The use of satellite derived fluxes may prove to be valuable sources in predicting sea ice and monitoring chemical and biological aspects within the SO. Our results indicate that recent changes in freshwater and salt transports are a major component of the deep-ocean warming in the SO. In particular, the role of changes in these fluxes in causing surface cooling and increasing deep oceanic storage of heat in the Southern Ocean is investigated.