The influence of the Deep Western Boundary Current in the Meridional Overturning Circulation in the South Atlantic

Abstract

This project aims to characterize and understand the causes for the variability in the transport of the Deep Western Boundary Current in the South Atlantic. We will use data obtained by currentmeters installed on Pressure Inverted Echo Sounders (PIES) and therefore called CPIES. The PIES array at 34.5°S between 44.5°W and 51.5°W was established by the South Atlantic Meridional Overturning Circulation (SAMOC-BR). The objective of this project is to investigate whether the mesoescale variability of CCOP may be associated with the presence of propagating signals and eddies and how much of this signal contributes to the Meridional Overturning Circulation. The CPIES in situ time series of the current velocity will be considered the most precise estimates. However, the time series is relatively short, from 2009 to 2014. Therefore, the use of an oceanic model (HYCOM) will allow us to examine the transport variability at various timescales and at an intradecadal projection. Altimetric satellite data will be used in combination with previous sources to test if the mesoscale fluctuations occurring in the deep current can be concomitantly observed at the sea surface height anomaly and its derived variables. It should be remembered that altimeters observe oceanic features in an integrated fashion along the water column. (AU)