CoAuthors

Shenfu Dong (University of Miami/CIMAS and National Oceanic and Atmospheric Administration/AOML, USA); Francis Bringas (National Oceanic and Atmospheric Administration / AOML, country)

This work present results that use blended satellite altimetry observations together with XBT, Argo profiling float, and climatological data to investigate the year-to-year variability of the meridional overturning circulation (MOC) and meridional heat transport (MHT) along 35°S since 1993. The barotropic and baroclinic components are extracted from the altimetric and hydrographic records. The baroclinic component is validated using the XBT derived MHT and MOC estimates. Results from the altimetry-based methodology during 1993-2011 indicate that the MHT ranges between a slightly negative value of -0.07PW and a large positive value of 1.11PW. Large interannual variability is observed with amplitudes of up to 1PW, which is comparable to similar values derived from XBT measurements. Changes in MOC and MHT are analyzed in terms of variations of the wind field and in the subtropical gyre, which has exhibited a warming trend during the last 20 years. Results obtained from this study demonstrate the importance of satellite altimetry observations for MOC studies in the South Atlantic Ocean and in particular to extend the time series of the in situ observational record and to obtain estimates where observations are not available.