Letter | Published:

Vigorous exchange between the Indian and Atlantic oceans at the end of the past five glacial periods

Nature volume 430, pages 661665 (05 August 2004) | Download Citation

Subjects

Abstract

The magnitude of heat and salt transfer between the Indian and Atlantic oceans through ‘Agulhas leakage’ is considered important for balancing the global thermohaline circulation1,2,3. Increases or reductions of this leakage lead to strengthening or weakening of the Atlantic meridional overturning and associated variation of North Atlantic Deep Water formation4,5,6. Here we show that modern Agulhas waters, which migrate into the south Atlantic Ocean in the form of an Agulhas ring, contain a characteristic assemblage of planktic foraminifera. We use this assemblage as a modern analogue to investigate the Agulhas leakage history over the past 550,000 years from a sediment record in the Cape basin. Our reconstruction indicates that Indian–Atlantic water exchange was highly variable: enhanced during present and past interglacials and largely reduced during glacial intervals. Coherent variability of Agulhas leakage with northern summer insolation suggests a teleconnection to the monsoon system. The onset of increased Agulhas leakage during late glacial conditions took place when glacial ice volume was maximal, suggesting a crucial role for Agulhas leakage in glacial terminations, timing of interhemispheric climate change7 and the resulting resumption of the Atlantic meridional overturning circulation6.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    Communication between oceans. Nature 382, 399–400 (1996)

  2. 2.

    et al. Indian-Atlantic interocean exchange: Dynamics, estimation and impact. J. Geophys. Res. 104, 20885–20910 (1999)

  3. 3.

    The brawniest retroflection. Nature 421, 904–905 (2003)

  4. 4.

    , & Stability of the Atlantic overturning circulation: Competition between Bering Strait freshwater flux and Agulhas heat and salt sources. J. Phys. Oceanogr. 31, 2385–2402 (2001)

  5. 5.

    , , & Response of the Atlantic overturning circulation to South Atlantic sources of buoyancy. Glob. Planet. Change 34, 293–311 (2002)

  6. 6.

    & Southern Ocean origin for the resumption of Atlantic thermohaline circulation during deglaciation. Nature 424, 532–536 (2003)

  7. 7.

    Greenland-Antarctic phase relations and millennial time-scale climate fluctuations in the Greenland ice-cores. Quat. Sci. Rev. 22, 1631–1646 (2003)

  8. 8.

    , , & Thermocline and intermediate water communication between the South Atlantic and Indian oceans. J. Geophys. Res. 97, 7223–7240 (1992)

  9. 9.

    & Origins and variability of the Benguela Current. J. Geophys. Res. 101, 897–906 (1996)

  10. 10.

    in The South Atlantic: Present and Past Circulation (eds Wefer, G., Berger, W. H., Siedler, G. & Webb, D. J.) 125–162 (Springer, Berlin/Heidelberg, 1996)

  11. 11.

    & An estimate of global ocean circulation and heat fluxes. Nature 382, 436–439 (1996)

  12. 12.

    et al. A 450-kyr record of hydrological conditions on the western Agulhas Bank Slope, south of Africa. Mar. Geol. 180, 183–201 (2002)

  13. 13.

    , & Pleistocene fluctuations in the Agulhas Current Retroflection based on the calcareous plankton record. Mar. Micropaleontol. 37, 1–22 (1999)

  14. 14.

    et al. MARE and ACSEX: new research programmes on the Agulhas Current System. S. Afr. J. Sci. 96 (2000)

  15. 15.

    et al. Observations of a young Agulhas ring Astrid, during MARE in March 2000. Deep-Sea Res. II 50, 167–195 (2003)

  16. 16.

    & in Micropaleontology of Oceans (eds Funnell, B. M. & Riedel, W. R.) 105–149 (Cambridge Univ. Press, London, 1971)

  17. 17.

    & Ecology of planktonic foraminifera and biogeographic patterns of life and fossil assemblages in the Indian ocean. Micropaleontology 23, 369–414 (1977)

  18. 18.

    & A planktic foraminiferal transfer function for the southern South Atlantic Ocean. Mar. Micropaleontol. 34, 213–234 (1998)

  19. 19.

    et al. in Milankovitch and Climate I (eds Berger, A. L., Imbrie, J., Hays, J. D., Kukla, J. & Salzman, J.) 269–305 (Reidel, Hingham, Massachusetts, 1984)

  20. 20.

    , & in Reconstructing Ocean History: A Window into the Future (eds Abrantes, F. & Mix, A.) 35–55 (Kluwer Academic/Plenum, New York, 1999)

  21. 21.

    , & Anomalous occurrences of Neogloboquadrina pachyderma (left) in a 420-ky upwelling record from Walvis Ridge (SE Atlantic). Mar. Micropaleontol. 40, 23–42 (2000)

  22. 22.

    et al. Late Quaternary sea-surface temperature variations in the southeast Atlantic: a planktic foraminifer faunal record of the past 600000 yr (IMAGES II MD962085). Mar. Geol. 180, 163–181 (2002)

  23. 23.

    , & Mid-Brunhes century-scale diatom sea surface temperature and sea ice records from the Atlantic sector of the Southern Ocean (ODP Leg 177, Sites 1093, 1094 and core PS2089–2). Palaeogeogr. Palaeoclimatol. Palaeoecol. 182, 305–328 (2002)

  24. 24.

    & Late Quaternary surface circulation of the southern Indian Ocean and its relationship to orbital variations. Paleoceanography 7, 79–117 (1992)

  25. 25.

    , & Glacial surface temperatures of the southeast Atlantic Ocean. Science 293, 2077–2079 (2001)

  26. 26.

    , , & An oceanic teleconnection between the equatorial and southern Indian Ocean. Geophys. Res. Lett. 29(16), doi:101029/2001GL014542 (2002)

  27. 27.

    & Late Quaternary history of the Agulhas current. Paleoceanography 5, 479–486 (1990)

  28. 28.

    et al. Eddies and dipoles around South Madagascar: formation, pathways and large-scale impact. Deep-Sea Res. I 51, 383–400 (2004)

  29. 29.

    , , & 340,000-year centennial-scale marine record of Southern Hemisphere climatic oscillation. Science 301, 948–952 (2003)

  30. 30.

    , & Comparison of interglacial stages in the South Atlantic sector of the southern ocean for the past 450 kyr: implications for Marine Isotope Stage (MIS) 11. Glob. Planet. Change 24, 7–26 (2000)

  31. 31.

    , & Macintosh program performs time-series analysis. Eos Trans. AGU 77, 379 (1996)

Download references

Acknowledgements

The MARE/CLIVARNET project was sponsored by two NWO grants (bilateral cooperation programme NWO-DFG). R.A. acknowledges funding from a NERC grant. R.S. is grateful to the German Science Foundation (DFG) and the IMAGES programme for sponsoring core retrieval and analytical work. We thank M. Segl and P. Mueller for measuring isotopes and alkenones, respectively. We thank the captain and crew of R/V Pelagia and R/V Agulhas as well as the Royal NIOZ technicians. We thank all MARE team members for discussion. This is a publication of the Netherlands Research School of Sedimentary Geology (NSG).

Author information

Affiliations

  1. Department of Paleoecology and Paleoclimatology, Faculty of Earth and Life Sciences, Vrije Universiteit, de Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands

    • Frank J. C. Peeters
    • , Gerald M. Ganssen
    • , Els Ufkes
    •  & Dick Kroon
  2. Department of Marine Chemistry and Geology (MCG), Royal Netherlands Institute for Sea Research (NIOZ), PO Box 59, 1790 AB Den Burg, Texel, The Netherlands

    • Frank J. C. Peeters
    •  & Geert-Jan A. Brummer
  3. School of GeoSciences, The University of Edinburgh, Grant Institute, The King's Buildings, Edinburgh EH9 3JW, UK

    • Ruth Acheson
  4. Faculty of Physics and Astronomy, Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands

    • Wilhelmus P. M. de Ruijter
  5. Département de Géologie et Océanographie, UMR 5805 EPOC, CNRS/Université de Bordeaux I, 33405 Talence, France

    • Ralph R. Schneider

Authors

  1. Search for Frank J. C. Peeters in:

  2. Search for Ruth Acheson in:

  3. Search for Geert-Jan A. Brummer in:

  4. Search for Wilhelmus P. M. de Ruijter in:

  5. Search for Ralph R. Schneider in:

  6. Search for Gerald M. Ganssen in:

  7. Search for Els Ufkes in:

  8. Search for Dick Kroon in:

Competing interests

The authors declare that they have no competing financial interests.

Corresponding author

Correspondence to Frank J. C. Peeters.

Supplementary information

PDF files

  1. 1.

    Supplementary Figure S1

    Depth–age relationship for cores GeoB-3603-2 and IMAGES II MD96-2081.

  2. 2.

    Supplementary Figure S2

    The δ18O of the benthic foraminifer Cibicides wuellerstorfi (red line) of the Cape Basin record after age tuning to the SPECMAP curve.

  3. 3.

    Supplementary Figure S3

    The planktic foraminifera fragmentation index of the Cape Basin record.

  4. 4.

    Supplementary Figure S4

    Location of plankton tow stations.

  5. 5.

    Supplementary Figure S5

    The integrated standing stock per species for nine plankton tow stations.

  6. 6.

    Supplementary Figure S6

    Blackman–Tukey spectral cross-correlation diagrams.

About this article

Publication history

Received

Accepted

Published

DOI

https://doi.org/10.1038/nature02785

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.