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Rapid sea-level rise along the Antarctic margins in response to increased glacial discharge

Abstract

The Antarctic shelf seas are a climatically and ecologically important region, and are at present receiving increasing amounts of freshwater from the melting of the Antarctic Ice Sheet and its fringing ice shelves1,2, primarily around the Antarctic Peninsula and the Amudsen Sea. In response, the surface ocean salinity in this region has declined in past decades3,4,5,6,7,8,9. Here, we assess the effects of the freshwater input on regional sea level using satellite measurements of sea surface height (for months with no sea-ice cover) and a global ocean circulation model. We find that from 1992 to 2011, sea-level rise along the Antarctic coast is at least 2 ± 0.8 mm yr−1 greater than the regional mean for the Southern Ocean south of 50° S. On the basis of the model simulations, we conclude that this sea-level rise is almost entirely related to steric adjustment, rather than changes in local ocean mass, with a halosteric rise in the upper ocean and thermosteric contributions at depth. We estimate that an excess freshwater input of 430 ± 230 Gt yr−1 is required to explain the observed sea-level rise. We conclude that accelerating discharge from the Antarctic Ice Sheet has had a pronounced and widespread impact on the adjacent subpolar seas over the past two decades.

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Figure 1: Regional anomaly in summer (January–April) sea-level trend, 1992–2011.
Figure 2: Time series of sea-level anomaly in the Antarctic subpolar seas, 1992–2011.
Figure 3: Ocean model simulation of the regional anomaly in sea-level trend, 1992–2007.

References

  1. Shepherd, A. et al. A reconciled estimate of ice-sheet mass balance. Science 338, 1183–1189 (2012).

    Article  Google Scholar 

  2. Shepherd, A., Wingham, D. & Rignot, E. Warm ocean is eroding West Antarctic Ice Sheet. Geophys. Res. Lett. 31, L23402 (2004).

    Article  Google Scholar 

  3. Jacobs, S. S., Giulivi, C. F. & Mele, P. A. Freshening of the Ross Sea during the late 20th century. Science 297, 386–389 (2002).

    Article  Google Scholar 

  4. Jacobs, S. S. & Giulivi, C. F. Large multidecadal salinity trends near the Pacific–Antarctic continental margin. J. Clim. 23, 4508–4524 (2010).

    Article  Google Scholar 

  5. Aoki, S., Rintoul, S. R., Ushio, S., Watanabe, S. & Bindoff, N. L. Freshening of the Adélie Land bottom water near 140° E. Geophys. Res. Lett. 32, L23601 (2005).

    Article  Google Scholar 

  6. Johnson, G. C., Purkey, S. G. & Bullister, J. L. Warming and freshening in the abyssal Southeastern Indian Ocean*. J. Clim. 21, 5351–5363 (2008).

    Article  Google Scholar 

  7. Ozaki, H., Obata, H., Naganobu, M. & Gamo, T. Long-term bottom water warming in the north Ross Sea. J. Oceanogr. 65, 235–244 (2009).

    Article  Google Scholar 

  8. Hellmer, H. H., Huhn, O., Gomis, D. & Timmermann, R. On the freshening of the northwestern Weddell Sea continental shelf. Ocean Sci. 7, 305–316 (2011).

    Article  Google Scholar 

  9. Williams, G. D. et al. Antarctic bottom water from the Adélie and George V Land coast, East Antarctica (140–149° E). J. Geophys. Res. 115, C04027 (2010).

    Google Scholar 

  10. Parkinson, C. L. & Cavalieri, D. J. Antarctic sea ice variability and trends, 1979–2010. Cryosphere 6, 871–880 (2012).

    Article  Google Scholar 

  11. Meehl, G. A. & Washington, W. M. CO2 climate sensitivity and snow-sea-ice albedo parameterization in an atmospheric GCM coupled to a mixed-layer ocean model. Climatic Change 16, 283–306 (1990).

    Article  Google Scholar 

  12. Orsi, A. H., Johnson, G. C. & Bullister, J. L. Circulation, mixing, and production of Antarctic bottom water. Prog. Oceanogr. 43, 55–109 (1999).

    Article  Google Scholar 

  13. Shepherd, A. et al. Recent loss of floating ice and the consequent sea level contribution. Geophys. Res. Lett. 37, L13503 (2010).

    Article  Google Scholar 

  14. Rignot, E., Velicogna, I., van den Broeke, M. R., Monaghan, A. & Lenaerts, J. T. M. Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise. Geophys. Res. Lett. 38, L05503 (2011).

    Article  Google Scholar 

  15. Bromwich, D. H., Nicolas, J. P. & Monaghan, A. J. An assessment of precipitation changes over Antarctica and the Southern Ocean since 1989 in contemporary global reanalyses. J. Clim. 24, 4189–4209 (2011).

    Article  Google Scholar 

  16. Depoorter, M. A. et al. Calving fluxes and basal melt rates of Antarctic ice shelves. Nature 502, 89–92 (2013).

    Article  Google Scholar 

  17. Rignot, E., Jacobs, S., Mouginot, J. & Scheuch, B. Ice-shelf melting around Antarctica. Science 341, 266–270 (2013).

    Article  Google Scholar 

  18. Le Traon, P. Y., Nadal, F. & Ducet, N. An improved mapping method of multisatellite altimeter data. J. Atmos. Ocean. Technol. 15, 522–534 (1998).

    Article  Google Scholar 

  19. Spence, P., Fyfe, J. C., Montenegro, A. & Weaver, A. J. Southern Ocean response to strengthening winds in an eddy-permitting global climate model. J. Clim. 23, 5332–5343 (2010).

    Article  Google Scholar 

  20. Leuliette, E. W. & Miller, L. Closing the sea level rise budget with altimetry, Argo, and GRACE. Geophys. Res. Lett. 36, L04608 (2009).

    Article  Google Scholar 

  21. Gregory, J. M. et al. Twentieth-century global-mean sea level rise: Is the whole greater than the sum of the parts? J. Clim. 26, 4476–4499 (2013).

    Article  Google Scholar 

  22. Meredith, M. P., Renfrew, I. A., Clarke, A., King, J. C. & Brandon, M. A. Impact of the 1997/98 ENSO on upper ocean characteristics in Marguerite Bay, western Antarctic Peninsula. J. Geophys. Res. 109, C09013 (2004).

    Article  Google Scholar 

  23. Purkey, S. G. & Johnson, G. C. Antarctic bottom water warming and freshening: Contributions to sea level rise, ocean freshwater budgets, and global heat gain. J. Clim. 26, 6105–6122 (2013).

    Article  Google Scholar 

  24. Munk, W. Ocean freshening, sea level rising. Science 300, 2041–2043 (2003).

    Article  Google Scholar 

  25. Riva, R. E. M., Bamber, J. L., Lavallée, D. A. & Wouters, B. Sea-level fingerprint of continental water and ice mass change from GRACE. Geophys. Res. Lett. 37, L19605 (2010).

    Article  Google Scholar 

  26. Purkey, S. G. & Johnson, G. C. Global contraction of Antarctic bottom water between the 1980s and 2000s. J. Clim. 25, 5830–5844 (2012).

    Article  Google Scholar 

  27. Dierssen, H. M., Smith, R. C. & Vernet, M. Glacial meltwater dynamics in coastal waters west of the Antarctic Peninsula. Proc. Natl Acad. Sci. USA 99, 1790–1795 (2002).

    Article  Google Scholar 

  28. Boyd, P. W. & Ellwood, M. J. The biogeochemical cycle of iron in the ocean. Nature Geosci. 3, 675–682 (2010).

    Article  Google Scholar 

  29. Stammerjohn, S. E., Martinson, D. G., Smith, R. C. & Ianuzzi, R. A. Sea ice in the western Antarctic Peninsula region: Spatio-temporal variability from ecological and climate change perspectives. Deep-Sea Res. II 55, 2041–2058 (2008).

    Article  Google Scholar 

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Acknowledgements

We thank J. Blundell for technical help and A. Blaker for assistance with modelling. We are grateful to A. Brearley, H. Bryden, J. Church, S. Drijfhout, P. Dutrieux, I. Haigh, L. Jullion, C. O’Donnell, M. Sonnewald and C. Wunsch for insightful comments and discussions at various stages of this work.

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C.D.R. conducted the data analysis, with regular input from A.C.N.G., A.J.G.N., C.W.H., M.P.M. and P.R.H. All these authors contributed to the writing of the manuscript. A.C.C. and D.J.W. assisted with the modelling component of the work.

Corresponding author

Correspondence to Craig D. Rye.

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The authors declare no competing financial interests.

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Rye, C., Naveira Garabato, A., Holland, P. et al. Rapid sea-level rise along the Antarctic margins in response to increased glacial discharge. Nature Geosci 7, 732–735 (2014). https://doi.org/10.1038/ngeo2230

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