Increased future ice discharge from Antarctica owing to higher snowfall

  • Nature volume 492, pages 239242 (13 December 2012)
  • doi:10.1038/nature11616
  • Download Citation


Anthropogenic climate change is likely to cause continuing global sea level rise1, but some processes within the Earth system may mitigate the magnitude of the projected effect. Regional and global climate models simulate enhanced snowfall over Antarctica, which would provide a direct offset of the future contribution to global sea level rise from cryospheric mass loss2,3 and ocean expansion4. Uncertainties exist in modelled snowfall5, but even larger uncertainties exist in the potential changes of dynamic ice discharge from Antarctica1,6 and thus in the ultimate fate of the precipitation-deposited ice mass. Here we show that snowfall and discharge are not independent, but that future ice discharge will increase by up to three times as a result of additional snowfall under global warming. Our results, based on an ice-sheet model7 forced by climate simulations through to the end of 2500 (ref. 8), show that the enhanced discharge effect exceeds the effect of surface warming as well as that of basal ice-shelf melting, and is due to the difference in surface elevation change caused by snowfall on grounded versus floating ice. Although different underlying forcings drive ice loss from basal melting versus increased snowfall, similar ice dynamical processes are nonetheless at work in both; therefore results are relatively independent of the specific representation of the transition zone. In an ensemble of simulations designed to capture ice-physics uncertainty, the additional dynamic ice loss along the coastline compensates between 30 and 65 per cent of the ice gain due to enhanced snowfall over the entire continent. This results in a dynamic ice loss of up to 1.25 metres in the year 2500 for the strongest warming scenario. The reported effect thus strongly counters a potential negative contribution to global sea level by the Antarctic Ice Sheet.

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  1. 1.

    et al. in Climate Change 2007: The Physical Science Basis (eds et al.) 747–845 (Cambridge Univ. Press, 2007)

  2. 2.

    et al. Response of the Greenland and Antarctic ice sheets to multi-millennial greenhouse warming in the Earth system model of intermediate complexity LOVECLIM. Surv. Geophys. 32, 397–416 (2011)

  3. 3.

    , , & Climate modification by future ice sheet changes and consequences for ice sheet mass balance. Clim. Dyn. 34, 301–324 (2010)

  4. 4.

    , & Climate change under a scenario near 1.5°C of global warming: monsoon intensification, ocean warming and steric sea level rise. Earth Syst. Dyn. 2, 25–35 (2011)

  5. 5.

    , , , & Simulated Antarctic precipitation and surface mass balance at the end of the twentieth and twenty-first centuries. Clim. Dyn. 28, 215–230 (2007)

  6. 6.

    , , , & Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise. Geophys. Res. Lett.. 38, L05503, (2011)

  7. 7.

    et al. The Potsdam Parallel Ice Sheet Model (PISM-PIK). Part 1: Model description. Cryosphere 5, 715–726 (2011)

  8. 8.

    , , , & A scaling approach to probabilistic assessment of regional climate change. J. Clim. 25, 3117–3144 (2012)

  9. 9.

    , , & Changes in Antarctic net precipitation in the 21st century based on Intergovernmental Panel on Climate Change (IPCC) model scenarios. J. Geophys. Res.. 112, D10107, (2007)

  10. 10.

    , , & Rheology of the Ronne Ice Shelf, Antarctica, inferred from satellite radar interferometry data using an inverse control method. Geophys. Res. Lett.. 32, L05503, (2005)

  11. 11.

    & Assessment of the importance of ice-shelf buttressing to ice-sheet flow. Geophys. Res. Lett.. 32, L04503, (2005)

  12. 12.

    & Rapid bottom melting widespread near Antarctic ice sheet grounding lines. Science 296, 2020–2023 (2002)

  13. 13.

    & Thin-film flows with wall slip: an asymptotic analysis of higher order glacier flow models. Q. J. Mech. Appl. Math. 63, 73–114 (2010)

  14. 14.

    et al. The RCP greenhouse gas concentrations and their extensions from 1765 to 2300. Clim. Change 109, 213–241 (2011)

  15. 15.

    et al. THE WCRP CMIP3 multimodel dataset: a new era in climate change research. Bull. Am. Meteorol. Soc. 88, 1383–1394 (2007)

  16. 16.

    , & Emulating IPCC AR4 atmosphere-ocean and carbon cycle models for projecting global-mean, hemispheric and land/ocean temperatures: MAGICC 6.0. Atmos. Chem. Phys. Discuss. 8, 6153–6272 (2008)

  17. 17.

    & A box model of circulation and melting in ice shelf caverns. Ocean Dyn. 60, 141–153 (2010)

  18. 18.

    , & Influence of sea ice cover and icebergs on circulation and water mass formation in a numerical circulation model of the Ross Sea, Antarctica. J. Geophys. Res.. 112, C11013, (2007)

  19. 19.

    et al. in Ocean, Ice and Atmosphere: Interactions at Antarctic Continental Margin (eds & ) 83–100 (AGU Antarctic Research Ser. Vol. 75, American Geophysical Union, 1998)

  20. 20.

    & Melting and freezing beneath Filchner-Ronne Ice Shelf, Antarctica. Geophys. Res. Lett.. 30, 1477, (2003)

  21. 21.

    , , , & Ocean circulation and ice-ocean interaction beneath the Amery Ice Shelf, Antarctica. J. Geophys. Res. 106, 22383–22400 (2001)

  22. 22.

    et al. Numerical modeling of ocean-ice interactions under Pine Island Bay's ice shelf. J. Geophys. Res.. 112, C10019, (2007)

  23. 23.

    & The dynamic response of the Greenland and Antarctic ice sheets to multiple-century climatic warming. J. Clim. 12, 2169–2188 (1999)

  24. 24.

    , , & Uncertainty in future solid ice discharge from Antarctica. Cryosphere Discuss. 6, 673–714 (2012)

  25. 25.

    et al. Insignificant change in Antarctic snowfall since the International Geophysical Year. Science 313, 827–831 (2006)

  26. 26.

    , & An improved Antarctic dataset for high resolution numerical ice sheet models (ALBMAP v1). Earth Syst. Sci. Data 2, 247–260 (2010)

  27. 27.

    et al. The Potsdam Parallel Ice Sheet Model (PISM-PIK). Part 2: Dynamic equilibrium simulation of the Antarctic Ice Sheet. Cryosphere 5, 727–740 (2011)

  28. 28.

    et al. The representative concentration pathways: an overview. Clim. Change 109, 5–31 (2011)

  29. 29.

    , & An overview of CMIP5 and the experiment design. Bull. Am. Meteorol. Soc. 93, 485–498 (2012)

  30. 30.

    , , & Effects of basal-melting distribution on the retreat of ice-shelf grounding lines. Geophys. Res. Lett.. 35, L17503, (2008)

  31. 31.

    & Modeling drifting snow in Antarctica with a regional climate model: 2. Results. J. Geophys. Res.. 117, D05109, (2012)

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This study was supported by the German Federal Ministry of Education and Research (BMBF, grant 01LP1171A) and the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU, grant 11_II_093_Global_A_SIDS and LDCs).

Author information


  1. Potsdam Institute for Climate Impact Research (PIK), 14473 Potsdam, Germany

    • R. Winkelmann
    • , A. Levermann
    • , M. A. Martin
    •  & K. Frieler
  2. Physics Institute, Potsdam University, 14476 Potsdam, Germany

    • R. Winkelmann
    • , A. Levermann
    •  & M. A. Martin


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R.W. and A.L. designed and performed the research. M.A.M. contributed to the discussion of the results. K.F. provided the climate forcing. R.W. wrote the paper.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to R. Winkelmann.

Supplementary information

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