Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Climate warming during Antarctic ice sheet expansion at the Middle Miocene transition

Abstract

During the Middle Miocene climate transition about 14 million years ago, the Antarctic ice sheet expanded to near-modern volume. Surprisingly, this ice sheet growth was accompanied by a warming in the surface waters of the Southern Ocean, whereas a slight deep-water temperature increase was delayed by more than 200 thousand years. Here we use a coupled atmosphere–ocean model to assess the relative effects of changes in atmospheric CO2 concentration and ice sheet growth on regional and global temperatures. In the simulations, changes in the wind field associated with the growth of the ice sheet induce changes in ocean circulation, deep-water formation and sea-ice cover that result in sea surface warming and deep-water cooling in large swaths of the Atlantic and Indian ocean sectors of the Southern Ocean. We interpret these changes as the dominant ocean surface response to a 100-thousand-year phase of massive ice growth in Antarctica. A rise in global annual mean temperatures is also seen in response to increased Antarctic ice surface elevation. In contrast, the longer-term surface and deep-water temperature trends are dominated by changes in atmospheric CO2 concentration. We therefore conclude that the climatic and oceanographic impacts of the Miocene expansion of the Antarctic ice sheet are governed by a complex interplay between wind field, ocean circulation and the sea-ice system.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Figure 1: Palaeo-oceanographic records and temperature changes from the South Tasman Rise during the MMCT.
Figure 2: Climatic responses to an Antarctic ice sheet expansion in scenario ΔICE.
Figure 3: Climatic responses to a CO2 decline in scenario ΔCO2.

References

  1. Flower, B. P. & Kennett, J. P. The Middle Miocene climatic transition: East Antarctic ice sheet development, deep ocean circulation and global carbon cycling. Palaeogeogr. Palaeoclimatol. Palaeoecol. 108, 537–555 (1994).

    Article  Google Scholar 

  2. Holbourn, A., Kuhnt, W., Schulz, M. & Erlenkeuser, H. Impacts of orbital forcing and atmospheric carbon dioxide on Miocene ice-sheet expansion. Nature 438, 483–487 (2005).

    Article  Google Scholar 

  3. Langebroek, P., Paul, A. & Schulz, M. Antarctic ice-sheet response to atmospheric CO2 and insolation in the Middle Miocene. Clim. Past 5, 633–646 (2009).

    Article  Google Scholar 

  4. Shevenell, A. E., Kennett, J. P. & Lea, D. W. Middle Miocene ice sheet dynamics, deep-sea temperatures, and carbon cycling: A Southern Ocean perspective. Geochem. Geophys. Geosyst. 9, Q02006 (2008).

    Article  Google Scholar 

  5. Lear, C., Mawbey, E. & Rosenthal, Y. Cenozoic benthic foraminiferal Mg/Ca and Li/Ca records: Towards unlocking temperatures and saturation states. Paleoceanography 25, PA4215 (2010).

    Article  Google Scholar 

  6. Billups, K. & and Schrag, D. P. Paleotemperatures and ice-volume of the past 27 Myr revisited with paired Mg/Ca and stable isotope measurements on benthic foraminifera. Paleoceanography 17, 1003 (2002).

    Google Scholar 

  7. Zachos, J. C., Pagani, M., Sloan, L., Thomas, E. & Billups, K. Trends, rhythms, and aberrations in global climate 65 Ma to present. Science 292, 286–293 (2001).

    Google Scholar 

  8. Langebroek, P., Paul, A. & Schulz, M. Simulating the sea-level imprint on marine oxygen-isotope records during the Middle Miocene using an ice sheet-climate model. Paleoceanography 25, PA4203 (2010).

    Article  Google Scholar 

  9. Shevenell, A. E., Kennett, J. P. & Lea, D. W. Middle Miocene Southern Ocean cooling and Antarctic cryosphere expansion. Science 305, 1766–1770 (2004).

    Article  Google Scholar 

  10. Foster, G. L., Lear, C. H. & Rae, J. W. The evolution of pCO2, ice volume and climate during the middle Miocene. Earth Planet. Sci. Lett. 341, 243–254 (2012).

    Article  Google Scholar 

  11. Raymo, M. E. & Ruddiman, W. F. Tectonic forcing of late Cenozoic climate. Nature 359, 117–122 (1992).

    Article  Google Scholar 

  12. Kennett, J. P. Cenozoic evolution of Antarctic glaciation, the circum-Antarctic Ocean and their impact on global paleoceanography. J. Geophys. Res. 82, 3843–3860 (1975).

    Article  Google Scholar 

  13. Vincent, E. & Berger, W. H. in The Carbon Cycle and Atmospheric CO2: Natural Variations Archean to Present (eds Broecker, W. S. & Sundquist, E. T.) 455–468 (Geophysical Monograph Series 32, AGU, 1985).

    Google Scholar 

  14. Kump, L. R. & Arthur, M. A. Interpreting carbon-isotope excursions: Carbonate and organic matter. Chem. Geol. 161, 181–198 (1999).

    Article  Google Scholar 

  15. Lear, C., Rosenthal, Y., Coxall, H. & Wilson, P. Late Eocene to early Miocene ice sheet dynamics and the global carbon cycle. Paleoceanography 19, 1–11 (2004).

    Article  Google Scholar 

  16. Badger, M. P. et al. CO2 drawdown following the middle Miocene expansion of the Antarctic ice sheet. Paleoceanography 28, 42–53 (2013).

    Article  Google Scholar 

  17. Kuhnert, H., Bickert, T. & Paulsen, H. Southern Ocean frontal system changes precede Antarctic ice sheet growth during the middle Miocene. Earth Planet. Sci. Lett. 284, 630–638 (2009).

    Article  Google Scholar 

  18. Jungclaus, J. H. et al. Ocean circulation and tropical variability in the coupled model ECHAM5/MPI-OM. J. Clim. 19, 3952–3972 (2006).

    Article  Google Scholar 

  19. Micheels, A. et al. Analysis of heat transport mechanisms from a Late Miocene model experiment with a fully-coupled atmosphere–ocean general circulation model. Palaeogeogr. Palaeoclimatol. Palaeoecol. 304, 337–350 (2011).

    Article  Google Scholar 

  20. Knorr, G., Butzin, M., Micheels, A. & Lohmann, G. A warm Miocene climate at low atmospheric CO2 levels. Geophys. Res. Lett. 38, L20701 (2011).

    Article  Google Scholar 

  21. Henrot, A. et al. Effects of CO2, continental distribution, topography and vegetation changes on the climate at the Middle Miocene: A model study. Clim. Past 6, 675–694 (2010).

    Article  Google Scholar 

  22. Krapp, M. & Jungclaus, J. H. The Middle Miocene climate as modelled in an atmosphere–ocean– biosphere model. Clim. Past 7, 1169–1188 (2011).

    Article  Google Scholar 

  23. Bradshaw, C. D. et al. The relative roles of CO2 and palaeogeography in determining late Miocene climate: Results from a terrestrial model–data comparison. Clim. Past 8, 1301–1307 (2012).

    Article  Google Scholar 

  24. DeConto, R. M., Pollard, D. & Harwood, D. Sea ice feedback and Cenozoic evolution of Antarctic climate and ice sheets. Paleoceanography 22, PA3214 (2007).

    Article  Google Scholar 

  25. Goldner, A., Huber, M. & Caballero, R. Does Antarctic glaciation cool the world? Clim. Past 9, 173–189 (2013).

    Article  Google Scholar 

  26. DeConto, R. M. & Pollard, D. Rapid Cenozoic glaciation of Antarctica induced by declining atmospheric CO2 . Nature 421, 245–249 (2003).

    Article  Google Scholar 

  27. Roeckner, E. et al. Sensitivity of simulated climate to horizontal and vertical resolution in the ECHAM5 atmosphere model. J. Clim. 19, 3771–3791 (2006).

    Article  Google Scholar 

  28. Marsland, S. J., Haak, H., Jungclaus, J. H., Latif, M. & Röske, F. The Max-Planck-Institute global ocean/sea ice model with orthogonal curvilinear coordinates. Ocean Modelling 5, 91–127 (2003).

    Article  Google Scholar 

  29. Tripati, A. K. et al. Coupling of CO2 and ice sheet stability over major climate transitions of the last 20 million Years. Science 326, 1394–1397 (2009).

    Article  Google Scholar 

  30. van de Wal, R. S. W., de Boer, B., Lourens, L. J., Köhler, P. & Bintanja, R. Reconstruction of a continuous high-resolution CO2 record over the past 20 million years. Clim. Past 7, 1459–1469 (2011).

    Article  Google Scholar 

Download references

Acknowledgements

We thank S. Barker, I. Hall and P. Köhler for comments on this study and the colleagues in the Paleoclimate Dynamics group at the Alfred Wegener Institute Helmholtz Center for Polar and Marine Research (AWI) in Bremerhaven for general support. This study is promoted by the PACES programme of the AWI and by the Helmholtz Climate Initiative REKLIM (Regional Climate Change), a joint research project of the Helmholtz Association of German research centres (HGF).

Author information

Authors and Affiliations

Authors

Contributions

G.K. and G.L. designed the research. G.K. carried out the experiments. G.K. and G.L. carried out the analysis and wrote the paper.

Corresponding author

Correspondence to Gregor Knorr.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 9346 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Knorr, G., Lohmann, G. Climate warming during Antarctic ice sheet expansion at the Middle Miocene transition. Nature Geosci 7, 376–381 (2014). https://doi.org/10.1038/ngeo2119

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ngeo2119

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing