Review Article | Published:

On the role of the Agulhas system in ocean circulation and climate

Nature volume 472, pages 429436 (28 April 2011) | Download Citation

Abstract

The Atlantic Ocean receives warm, saline water from the Indo-Pacific Ocean through Agulhas leakage around the southern tip of Africa. Recent findings suggest that Agulhas leakage is a crucial component of the climate system and that ongoing increases in leakage under anthropogenic warming could strengthen the Atlantic overturning circulation at a time when warming and accelerated meltwater input in the North Atlantic is predicted to weaken it. Yet in comparison with processes in the North Atlantic, the overall Agulhas system is largely overlooked as a potential climate trigger or feedback mechanism. Detailed modelling experiments—backed by palaeoceanographic and sustained modern observations—are required to establish firmly the role of the Agulhas system in a warming climate.

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Acknowledgements

Fig. 1 was produced by E. Van Sebille and Fig. 2 was produced by H. Van Aken. We thank D. leBars for discussions. L.M.B. is funded by the US National Science Foundation through the ACT project, award no. OCE-0850891. W.P.M.D.R. is funded by the Netherlands Organization for Scientific Research through the INATEX program, ZKO no. 839.08.430. R.Z. receives funding from the Ministerio de Ciencia e Innovación, Spain, through grant CGL2007-61579/CLI. A.B. and R.Z. acknowledge funding by the EC FP7 Marie Curie ITN GATEWAYS. This document is based on work partially supported by the US National Science Foundation under Grant OCE-0938349 to the Scientific Committee on Oceanic Research.

Author information

Affiliations

  1. Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Causeway, Florida 33149, USA

    • Lisa M. Beal
  2. Institute for Marine and Atmospheric Research, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands

    • Wilhelmus P. M. De Ruijter
  3. Leibniz-Institut für Meereswissenschaften (IFM-GEOMAR), Düsternbrooker Weg 20, 24105 Kiel, Germany

    • Arne Biastoch
  4. Institució Catalana de Recerca i Estudis Avançats (ICREA), Institut de Ciència i Tecnologia Ambientals (ICTA), Departament de Física, Universitat Autònoma de Barcelona, Bellaterra E-08193, Spain

    • Rainer Zahn
  5. NOAA Pacific Marine Environmental Laboratory, 7600 Sand Point Way NE, Seattle, Washington 98115, USA.

    • Meghan Cronin
  6. South African Environmental Observation Network, Private Bag X2, Roggebaai 8012, South Africa.

    • Juliet Hermes
  7. Department of Oceanography, University of Cape Town, 7700 Rondebosch, South Africa.

    • Johann Lutjeharms
  8. National Oceanography Centre, Southampton, European Way, Southampton SO14 3ZH, UK.

    • Graham Quartly
    •  & Paolo Cipollini
  9. Department of Earth and Planetary Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.

    • Tomoki Tozuka
  10. Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.

    • Sheekela Baker-Yeboah
  11. South African Institute for Aquatic Biodiversity, Private Bag 1015, Grahamstown 6140, South Africa.

    • Thomas Bornman
  12. Institute for Marine and Atmospheric Research, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands.

    • Henk Dijkstra
  13. School of Earth and Ocean Sciences, Cardiff University, Park Place, Cardiff CF10 3AT, UK.

    • Ian Hall
  14. Leibniz-Institut für Meereswissenschaften (IFM-GEOMAR), Düsternbrooker Weg 20, 24105 Kiel, Germany.

    • Wonsun Park
  15. Faculty of Earth and Life Sciences, Section Marine Biogeology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.

    • Frank Peeters
  16. Laboratoire de Physique des Oceans (UMR 6523 CNRS, IFREMER, IRD, UBO), LMI ICEMASA, Department of Oceanography, University of Cape Town, Cape Town, 7700 Rondebosch, South Africa.

    • Pierrick Penven
  17. NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, The Netherlands.

    • Herman Ridderinkhof
    •  & Jens Zinke

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  1. SCOR/WCRP/IAPSO Working Group 136

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Contributions

The ideas presented here were developed jointly by L.M.B., W.P.M.D.R., A.B., R.Z. and the SCOR/WCRP/IAPSO Working Group 136 on the Climatic Importance of the Greater Agulhas System. Working Group 136 is sponsored by the Scientific Committee for Oceanic Research (SCOR), the World Climate Research Program (WCRP) and the International Association for the Physical Sciences of the Ocean (IAPSO).

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Lisa M. Beal.

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https://doi.org/10.1038/nature09983

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