EGU2020-6123, updated on 02 May 2024
EGU General Assembly 2020
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Temporal Variability of the Meridional Overturning Cells in the South Atlantic

Marion Kersalé1,2, Christopher Meinen2, Renellys Perez2, Matthieu Le Hénaff1,2, Daniel Valla3, Tarron Lamont4,5, Olga Sato6, Shenfu Dong2, Thierry Terre7, Mathias van Caspel6, Maria Paz Chidichimo3,8,9, Marcel van den Berg4, Sabrina Speich10, Alberto Piola3,9,11, Edmo Campos6,12, Isabelle Ansorge5, Denis Volkov1,2, Rick Lumpkin2, and Silvia Garzoli1,2
Marion Kersalé et al.
  • 1Cooperative Institute for Marine and Atmospheric Studies, University of Miami, Miami, USA
  • 2NOAA Atlantic Oceanographic and Meteorological Laboratory, Miami, USA
  • 3Servicio de Hidrografía Naval, Buenos Aires, Argentina
  • 4Oceans and Coasts Research Branch, Department of Environmental Affairs, Cape Town, South Africa
  • 5Oceanography Department, University of Cape Town, Rondebosch 7701, South Africa
  • 6Oceanographic Institute, University of São Paulo, São Paulo, Brazil
  • 7IFREMER, Univ. Brest, CNRS, IRD, Laboratoire d'Océanographie Physique et Spatiale (LOPS), IUEM, Plouzané, France
  • 8Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
  • 9Instituto Franco-Argentino sobre Estudio del Clima y sus Impactos (UMI-IFAECI/CNRS- CONICET-UBA), Buenos Aires, Argentina
  • 10Laboratoire de Météorologie Dynamique – IPSL, Ecole Normale Supérieure, Paris, France
  • 11Universidad de Buenos Aires, Buenos Aires, Argentina
  • 12Dept. of Biology, Chemistry and Env. Sciences, School of Arts and Sciences, American University of Sharjah, United Arab Emirates

Variations in the Meridional Overturning Circulation (MOC) are known to have important impacts on global scale climate phenomena including precipitation patterns, surface air temperatures, coastal sea level, and extreme weather. The MOC flow structure in the South Atlantic is thought to control the stability of the entire global MOC system. Given this importance, significant resources have been invested on observing the MOC in the South Atlantic over the past decade. Multiple years of full-depth daily observations from moored instruments at 34.5°S are used to calculate the meridional transports near the western and eastern boundaries, as well as the basin-wide interior transports, via geostrophic methods. These transport estimates are combined with Ekman transports derived from satellite wind products to yield daily estimates of the total meridional transports. Analysis of the MOC volume transport using all available moored instruments from 2013 to 2017 allows us to quantify for the first time the daily volume transport of both the upper and abyssal overturning cells at 34.5°S. The structure of these flows is characterized in unprecedented detail; no statistically significant trend is detectable in either cell. Abyssal-cell transport variability is largely independent of the transport variability in the upper-cell. Analysis of this new data set is crucial for improving our understanding of the temporal and spatial scales of variability that governs MOC related flows, and for disentangling their respective roles in modulating its overall variability.

How to cite: Kersalé, M., Meinen, C., Perez, R., Le Hénaff, M., Valla, D., Lamont, T., Sato, O., Dong, S., Terre, T., van Caspel, M., Chidichimo, M. P., van den Berg, M., Speich, S., Piola, A., Campos, E., Ansorge, I., Volkov, D., Lumpkin, R., and Garzoli, S.: Temporal Variability of the Meridional Overturning Cells in the South Atlantic, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6123,, 2020.

This abstract will not be presented.