Global environmental consequences of twenty-first-century ice-sheet melt


Government policies currently commit us to surface warming of three to four degrees Celsius above pre-industrial levels by 2100, which will lead to enhanced ice-sheet melt. Ice-sheet discharge was not explicitly included in Coupled Model Intercomparison Project phase 5, so effects on climate from this melt are not currently captured in the simulations most commonly used to inform governmental policy. Here we show, using simulations of the Greenland and Antarctic ice sheets constrained by satellite-based measurements of recent changes in ice mass, that increasing meltwater from Greenland will lead to substantial slowing of the Atlantic overturning circulation, and that meltwater from Antarctica will trap warm water below the sea surface, creating a positive feedback that increases Antarctic ice loss. In our simulations, future ice-sheet melt enhances global temperature variability and contributes up to 25 centimetres to sea level by 2100. However, uncertainties in the way in which future changes in ice dynamics are modelled remain, underlining the need for continued observations and comprehensive multi-model assessments.

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Fig. 1: Simulated and observed ice-sheet mass balance.
Fig. 2: Sea-level contributions from Greenland and Antarctica.
Fig. 3: Causes of changes in ice-sheet thickness by 2100.
Fig. 4: Environmental consequences of twenty-first-century ice-sheet meltwater flux.
Fig. 5: Effect of ice-sheet melt on the AMOC.

Data availability

CMIP5 data were downloaded from Antarctic bedrock topography and ice thickness data are from the BEDMAP2 compilation, available at Greenland topography and ice thickness data are from BedMachine v3, available at Greenland mass balance and geothermal heat flux data are available from the seaRISE website: Information on Antarctic surface mass balance data are available at Antarctic geothermal heat flux data are available at Drainage basin outlines as shown in Fig. 3 are based on ICESat data96. Antarctic grounding lines and calving lines shown in Fig. 3a are from the MODIS-MOA 2009 dataset97,98. The datasets generated and analysed during this study are also available from the corresponding author on reasonable request.


  1. 1.

    The IMBIE team. Mass balance of the Antarctic Ice Sheet from 1992 to 2017. Nature 558, 219–222 (2018).

    ADS  Google Scholar 

  2. 2.

    Forsberg, R., Sørensen, L. & Simonsen, S. Greenland and Antarctic Ice Sheet mass changes and effects on global sea level. Surv. Geophys. 38, 89–104 (2017).

    ADS  Google Scholar 

  3. 3.

    Chen, X. et al. The increasing rate of global mean sea-level rise during 1993–2014. Nat. Clim. Chang. 7, 492–495 (2017).

    ADS  Google Scholar 

  4. 4.

    Huss, M. & Hock, R. A new model for global glacier change and sea-level rise. Front. Earth Sci. 3, 54 (2015).

    ADS  Google Scholar 

  5. 5.

    Bamber, J. L., Westaway, R. M., Marzeion, B. & Wouters, B. The land ice contribution to sea level during the satellite era. Environ. Res. Lett. 13, 063008 (2018).

    ADS  Google Scholar 

  6. 6.

    Dieng, H. B., Cazenave, A., Meyssignac, B. & Ablain, M. New estimate of the current rate of sea level rise from a sea level budget approach. Geophys. Res. Lett. 44, 3744–3751 (2017).

    ADS  Google Scholar 

  7. 7.

    Caesar, L., Rahmstorf, S., Robinson, A., Feulner, G. & Saba, V. Observed fingerprint of a weakening Atlantic Ocean overturning circulation. Nature 556, 191–196 (2018).

    ADS  CAS  Google Scholar 

  8. 8.

    Thornalley, D. J. R. et al. Anomalously weak Labrador Sea convection and Atlantic overturning during the past 150 years. Nature 556, 227–230 (2018).

    ADS  CAS  Google Scholar 

  9. 9.

    Raftery, A. E., Zimmer, A., Frierson, D. M. W., Startz, R. & Liu, P. Less than 2 °C warming by 2100 unlikely. Nat. Clim. Chang. 7, 637–641 (2017).

    ADS  CAS  PubMed  PubMed Central  Google Scholar 

  10. 10.

    Lenton, T. M. et al. Tipping elements in the Earth’s climate system. Proc. Natl Acad. Sci. USA 105, 1786–1793 (2008).

    ADS  CAS  MATH  Google Scholar 

  11. 11.

    Rignot, E., Mouginot, J., Morlighem, M., Seroussi, H. & Scheuchl, B. Widespread, rapid grounding line retreat of Pine Island, Thwaites, Smith, and Kohler glaciers, West Antarctica, from 1992 to 2011. Geophys. Res. Lett. 41, 3502–3509 (2014).

    ADS  Google Scholar 

  12. 12.

    Joughin, I., Smith, B. E. & Medley, B. Marine ice sheet collapse potentially under way for the Thwaites Glacier basin, West Antarctica. Science 344, 735–738 (2014).

    ADS  CAS  Google Scholar 

  13. 13.

    Vitousek, S. et al. Doubling of coastal flooding frequency within decades due to sea-level rise. Sci. Rep. 7, 1399 (2017).

    ADS  PubMed  PubMed Central  Google Scholar 

  14. 14.

    King, A. D. & Harrington, L. J. The inequality of climate change from 1.5 to 2 °C of global warming. Geophys. Res. Lett. 45, 5030–5033 (2018).

    ADS  Google Scholar 

  15. 15.

    Kopp, R. E. et al. Evolving understanding of Antarctic ice-sheet physics and ambiguity in probabilistic sea-level projections. Earths Futur. 5, 1217–1233 (2017).

    ADS  Google Scholar 

  16. 16.

    Jackson, L. P., Grinsted, A. & Jevrejeva, S. 21st century sea-level rise in line with the Paris Accord. Earths Futur. 6, 213–229 (2018).

    ADS  Google Scholar 

  17. 17.

    Ritz, C. et al. Potential sea-level rise from Antarctic ice-sheet instability constrained by observations. Nature 528, 115–118 (2015).

    ADS  CAS  PubMed  Google Scholar 

  18. 18.

    Golledge, N. et al. The multi-millennial Antarctic commitment to future sea-level rise. Nature 526, 421–425 (2015).

    ADS  CAS  Google Scholar 

  19. 19.

    Vizcaino, M. et al. Coupled simulations of Greenland Ice Sheet and climate change up to A.D. 2300. Geophys. Res. Lett. 42, 3927–3935 (2015).

    ADS  Google Scholar 

  20. 20.

    DeConto, R. & Pollard, D. Contribution of Antarctica to past and future sea-level rise. Nature 531, 591–597 (2016).

    ADS  CAS  PubMed  Google Scholar 

  21. 21.

    Weaver, A. J. et al. Stability of the Atlantic meridional overturning circulation: a model intercomparison. Geophys. Res. Lett. 39, L20709 (2012).

    ADS  Google Scholar 

  22. 22.

    Collins, M. et al. in Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (eds Stocker, T. et al.) 1029–1136 (Cambridge Univ. Press, Cambridge, 2013).

  23. 23.

    Bintanja, R., van Oldenborgh, G. J. & Katsman, C. A. The effect of increased fresh water from Antarctic ice shelves on future trends in Antarctic sea ice. Ann. Glaciol. 56, 120–126 (2015).

    ADS  Google Scholar 

  24. 24.

    Bueler, E. & Brown, J. Shallow shelf approximation as a “sliding law” in a thermomechanically coupled ice sheet model. J. Geophys. Res. 114, F03008 (2009).

    ADS  Google Scholar 

  25. 25.

    Bernales, J., Rogozhina, I. & Thomas, M. Melting and freezing under Antarctic ice shelves from a combination of ice-sheet modelling and observations. J. Glaciol. 63, 731–744 (2017).

    ADS  Google Scholar 

  26. 26.

    Golledge, N. et al. Antarctic contribution to meltwater pulse 1A from reduced Southern Ocean overturning. Nat. Commun. 5, 5107 (2014).

    CAS  Google Scholar 

  27. 27.

    Bakker, P., Clark, P. U., Golledge, N. R., Schmittner, A. & Weber, M. E. Centennial-scale Holocene climate variations amplified by Antarctic Ice Sheet discharge. Nature 541, 72–76 (2017).

    ADS  CAS  Google Scholar 

  28. 28.

    Menviel, L., Timmermann, A., Timm, O. E. & Mouchet, A. Climate and biogeochemical response to a rapid melting of the West Antarctic Ice Sheet during interglacials and implications for future climate. Paleoceanography 25, PA4231 (2010).

    ADS  Google Scholar 

  29. 29.

    Weber, M. et al. Millennial-scale variability in Antarctic ice-sheet discharge during the last deglaciation. Nature 510, 134–138 (2014).

    ADS  CAS  Google Scholar 

  30. 30.

    Bronselaer, B. et al. Change in future climate due to Antarctic meltwater. Nature 564, 53–58 (2018).

    CAS  PubMed  PubMed Central  Google Scholar 

  31. 31.

    Frölicher, T. L., Fischer, E. M. & Gruber, N. Marine heatwaves under global warming. Nature 560, 360–364 (2018).

    ADS  PubMed  PubMed Central  Google Scholar 

  32. 32.

    Ruthrof, K. X. et al. Subcontinental heat wave triggers terrestrial and marine, multi-taxa responses. Sci. Rep. 8, 13094 (2018).

    ADS  PubMed  PubMed Central  Google Scholar 

  33. 33.

    Hutchings, J. K. & Perovich, D. K. Preconditioning of the 2007 sea-ice melt in the eastern Beaufort Sea, Arctic Ocean. Ann. Glaciol. 56, 94–98 (2015).

    ADS  Google Scholar 

  34. 34.

    Rahmstorf, S. Bifurcations of the Atlantic thermohaline circulation in response to changes in the hydrological cycle. Nature 378, 145–149 (1995).

    ADS  CAS  Google Scholar 

  35. 35.

    Stommel, H. Thermohaline convection with two stable regimes of flow. Tellus 13, 224–230 (1961).

    ADS  Google Scholar 

  36. 36.

    Bakker, P. et al. Fate of the Atlantic Meridional Overturning Circulation: strong decline under continued warming and Greenland melting. Geophys. Res. Lett. 43, 12252–12260 (2016).

    ADS  Google Scholar 

  37. 37.

    Liu, W., Xie, S.-P., Liu, Z. & Zhu, J. Overlooked possibility of a collapsed Atlantic Meridional Overturning Circulation in warming climate. Sci. Adv. 3, e1601666 (2017).

    ADS  PubMed  PubMed Central  Google Scholar 

  38. 38.

    Rind, D. et al. Multi-century instability of the Atlantic Meridional Circulation in rapid warming simulations with GISS ModelE2. J. Geophys. Res. 123, 6331–6355 (2018).

    Google Scholar 

  39. 39.

    Edwards, T. L. et al. Revisiting Antarctic ice loss due to marine ice-cliff instability. Nature 566, (2019).

  40. 40.

    Noël, B. et al. A tipping point in refreezing accelerates mass loss of Greenland’s glaciers and ice caps. Nat. Commun. 8, 14730 (2017).

    ADS  PubMed  PubMed Central  Google Scholar 

  41. 41.

    Machguth, H. et al. Greenland meltwater storage in firn limited by near-surface ice formation. Nat. Clim. Chang. 6, 390–393 (2016).

    ADS  Google Scholar 

  42. 42.

    Fettweis, X. et al. Estimating the Greenland ice sheet surface mass balance contribution to future sea level rise using the regional atmospheric climate model MAR. Cryosphere 7, 469–489 (2013).

    ADS  Google Scholar 

  43. 43.

    Shannon, S. R. et al. Enhanced basal lubrication and the contribution of the Greenland ice sheet to future sea-level rise. Proc. Natl Acad. Sci. USA 110, 14156–14161 (2013).

    ADS  CAS  PubMed  PubMed Central  Google Scholar 

  44. 44.

    Fürst, J. J., Goelzer, H. & Huybrechts, P. Ice-dynamic projections of the Greenland ice sheet in response to atmospheric and oceanic warming. Cryosphere 9, 1039–1062 (2015).

    ADS  Google Scholar 

  45. 45.

    Seroussi, H. et al. Continued retreat of Thwaites Glacier, West Antarctica, controlled by bed topography and ocean circulation. Geophys. Res. Lett. 44, 6191–6199 (2017).

    ADS  Google Scholar 

  46. 46.

    Medley, B. et al. Temperature and snowfall in western Queen Maud Land increasing faster than climate model projections. Geophys. Res. Lett. 45, 1472–1480 (2018).

    ADS  Google Scholar 

  47. 47.

    Phillips, H. A. Surface meltstreams on the Amery ice shelf, East Antarctica. Ann. Glaciol. 27, 177–181 (1998).

    ADS  Google Scholar 

  48. 48.

    Bevan, S. L. et al. Centuries of intense surface melt on Larsen C ice shelf. Cryosphere 11, 2743–2753 (2017).

    ADS  Google Scholar 

  49. 49.

    Trusel, L. D. et al. Divergent trajectories of Antarctic surface melt under two twenty-first-century climate scenarios. Nat. Geosci. 8, 927–932 (2015).

    ADS  CAS  Google Scholar 

  50. 50.

    Bell, R. E., Banwell, A., Trusel, L. & Kingslake, J. Antarctic surface hydrology and impacts on ice sheet mass balance. Nat. Clim. Chang. 8, 1044–1052 (2018).

    ADS  Google Scholar 

  51. 51.

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

    ADS  Google Scholar 

  52. 52.

    Aschwanden, A., Bueler, E., Khroulev, C. & Blatter, H. An enthalpy formulation for glaciers and ice sheets. J. Glaciol. 58, 441–457 (2012).

    ADS  Google Scholar 

  53. 53.

    Feldmann, J., Albrecht, T., Khroulev, C., Pattyn, F. & Levermann, A. Resolution-dependent performance of grounding line motion in a shallow model compared to a full-Stokes model according to the MISMIP3d intercomparison. J. Glaciol. 60, 353–360 (2014).

    ADS  Google Scholar 

  54. 54.

    Golledge, N. R. et al. Antarctic climate and ice sheet configuration during a peak-warmth early Pliocene interglacial. Clim. Past 13, 959–975 (2017).

    Google Scholar 

  55. 55.

    Seroussi, H. & Morlighem, M. Representation of basal melting at the grounding line in ice flow models. Cryosphere 12, 3085–3096 (2018).

    ADS  Google Scholar 

  56. 56.

    Milillo, P. et al. On the short-term grounding zone dynamics of Pine Island Glacier, West Antarctica, observed with COSMO-SkyMed interferometric data. Geophys. Res. Lett. 44, 10436–10444 (2017).

    ADS  Google Scholar 

  57. 57.

    van den Broeke, M., Bus, C., Ettema, J. & Smeets, P. Temperature thresholds for degree-day modelling of Greenland ice sheet melt rates. Geophys. Res. Lett. 37, L18501 (2010).

    ADS  Google Scholar 

  58. 58.

    Hellmer, H. & Olbers, D. A two-dimensional model for the thermohaline circulation under an ice shelf. Antarct. Sci. 1, 325–336 (1989).

    ADS  Google Scholar 

  59. 59.

    Rignot, E. & Jacobs, S. S. Rapid bottom melting widespread near Antarctic Ice Sheet grounding lines. Science 296, 2020–2023 (2002).

    ADS  CAS  PubMed  PubMed Central  Google Scholar 

  60. 60.

    Hellmer, H., Kauker, F., Timmermann, R., Determann, J. & Rae, J. Twenty-first-century warming of a large Antarctic ice-shelf cavity by a redirected coastal current. Nature 485, 225–228 (2012).

    ADS  CAS  PubMed  PubMed Central  Google Scholar 

  61. 61.

    Levermann, A. et al. Kinematic first-order calving law implies potential for abrupt ice-shelf retreat. Cryosphere 6, 273–286 (2012).

    ADS  Google Scholar 

  62. 62.

    Fretwell, P. et al. Bedmap2: improved ice bed, surface and thickness datasets for Antarctica. Cryosphere 7, 375–393 (2013).

    ADS  Google Scholar 

  63. 63.

    Morlighem, M. et al. BedMachine v3: complete bed topography and ocean bathymetry mapping of Greenland from multibeam echo sounding combined with mass conservation. Geophys. Res. Lett. 44, 11051–11061 (2017).

    ADS  CAS  PubMed  PubMed Central  Google Scholar 

  64. 64.

    Van Wessem, J. et al. Improved representation of East Antarctic surface mass balance in a regional atmospheric climate model. J. Glaciol. 60, 761–770 (2014).

    Google Scholar 

  65. 65.

    Ettema, J. et al. Higher surface mass balance of the Greenland ice sheet revealed by high-resolution climate modeling. Geophys. Res. Lett. 36, L12501 (2009).

    ADS  Google Scholar 

  66. 66.

    Martos, Y. M. et al. Heat flux distribution of Antarctica unveiled. Geophys. Res. Lett. 44, 11417–11426 (2017).

    ADS  Google Scholar 

  67. 67.

    Shapiro, N. & Ritzwoller, M. Inferring surface heat flux distributions guided by a global seismic model: particular application to Antarctica. Earth Planet. Sci. Lett. 223, 213–224 (2004).

    ADS  CAS  Google Scholar 

  68. 68.

    Sallée, J.-B. et al. Assessment of Southern Ocean water mass circulation and characteristics in CMIP5 models: historical bias and forcing response. J. Geophys. Res. 118, 1830–1844 (2013).

    ADS  Google Scholar 

  69. 69.

    Turner, J., Bracegirdle, T. J., Phillips, T., Marshall, G. J. & Hosking, J. S. An initial assessment of Antarctic sea ice extent in the CMIP5 models. J. Clim. 26, 1473–1484 (2013).

    ADS  Google Scholar 

  70. 70.

    Bracegirdle, T. J. et al. Assessment of surface winds over the Atlantic, Indian, and Pacific Ocean sectors of the Southern Ocean in CMIP5 models: historical bias, forcing response, and state dependence. J. Geophys. Res. 118, 547–562 (2013).

    Google Scholar 

  71. 71.

    Naughten, K. A. et al. Future projections of Antarctic ice shelf melting based on CMIP5 scenarios. J. Clim. 31, 5243–5261 (2018).

    ADS  Google Scholar 

  72. 72.

    Goosse, H. et al. Description of the Earth system model of intermediate complexity LOVECLIM version 1.2. Geosci. Model Dev. 3, 603–633 (2010).

    ADS  Google Scholar 

  73. 73.

    Gent, P. R. & McWilliams, J. C. Isopycnal mixing in ocean circulation models. J. Phys. Oceanogr. 20, 150–155 (1990).

    ADS  Google Scholar 

  74. 74.

    Menviel, L., Timmermann, A., Timm, O. E. & Mouchet, A. Deconstructing the Last Glacial termination: the role of millennial and orbital-scale forcings. Quat. Sci. Rev. 30, 1155–1172 (2011).

    ADS  Google Scholar 

  75. 75.

    Abram, N. J. et al. Early onset of industrial-era warming across the oceans and continents. Nature 536, 411–418 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  76. 76.

    Menviel, L. et al. Southern Hemisphere westerlies as a driver of the early deglacial atmospheric CO2 rise. Nat. Commun. 9, 2503 (2018).

    ADS  CAS  PubMed  PubMed Central  Google Scholar 

  77. 77.

    Randall, D. A. et al. in Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (eds Solomon, S. et al.) 589–662 (Cambridge Univ. Press, Cambridge, 2007).

  78. 78.

    Gomez, N., Mitrovica, J. X., Huybers, P. & Clark, P. U. Sea level as a stabilizing factor for marine-ice-sheet grounding lines. Nat. Geosci. 3, 850–853 (2010).

    ADS  CAS  Google Scholar 

  79. 79.

    Dziewonski, A. M. & Anderson, D. L. Preliminary reference Earth model. Phys. Earth Planet. Inter. 25, 297–356 (1981).

    ADS  Google Scholar 

  80. 80.

    Lambeck, K., Smither, C. & Ekman, M. Tests of glacial rebound models for Fennoscandinavia based on instrumented sea- and lake-level records. Geophys. J. Int. 135, 375–387 (1998).

    ADS  Google Scholar 

  81. 81.

    Mitrovica, J. X. & Forte, A. M. A new inference of mantle viscosity based upon joint inversion of convection and glacial isostatic adjustment data. Earth Planet. Sci. Lett. 225, 177–189 (2004).

    ADS  CAS  Google Scholar 

  82. 82.

    Lambeck, K., Rouby, H., Purcell, A., Sun, Y. & Sambridge, M. Sea level and global ice volumes from the Last Glacial Maximum to the Holocene. Proc. Natl Acad. Sci. USA 111, 15296–15303 (2014).

    ADS  CAS  Google Scholar 

  83. 83.

    Stuhne, G. & Peltier, W. Reconciling the ICE-6G_C reconstruction of glacial chronology with ice sheet dynamics: the cases of Greenland and Antarctica. J. Geophys. Res. 120, 1841–1865 (2015).

    Google Scholar 

  84. 84.

    Aschwanden, A., Fahnestock, M. A. & Truffer, M. Complex Greenland outlet glacier flow captured. Nat. Commun. 7, 10524 (2016).

    ADS  CAS  PubMed  PubMed Central  Google Scholar 

  85. 85.

    Pauling, A. G., Bitz, C. M., Smith, I. J. & Langhorne, P. J. The response of the Southern Ocean and Antarctic sea ice to freshwater from ice shelves in an Earth system model. J. Clim. 29, 1655–1672 (2016).

    ADS  Google Scholar 

  86. 86.

    Merino, N. et al. Impact of increasing Antarctic glacial freshwater release on regional sea-ice cover in the Southern Ocean. Ocean Model. 121, 76–89 (2018).

    ADS  Google Scholar 

  87. 87.

    Dong, S., Sprintall, J., Gille, S. T. & Talley, L. Southern Ocean mixed-layer depth from Argo float profiles. J. Geophys. Res. 113, C06013 (2008).

    ADS  Google Scholar 

  88. 88.

    Dutrieux, P. et al. Strong sensitivity of Pine Island ice-shelf melting to climatic variability. Science 343, 174–178 (2014).

    ADS  CAS  Google Scholar 

  89. 89.

    Webber, B. G. et al. Mechanisms driving variability in the ocean forcing of Pine Island Glacier. Nat. Commun. 8, 14507 (2017).

    ADS  MathSciNet  CAS  PubMed  PubMed Central  Google Scholar 

  90. 90.

    Thompson, A. F., Heywood, K. J., Schmidtko, S. & Stewart, A. L. Eddy transport as a key component of the Antarctic overturning circulation. Nat. Geosci. 7, 879–884 (2014).

    ADS  CAS  Google Scholar 

  91. 91.

    Stewart, A. L. & Thompson, A. F. Eddy-mediated transport of warm Circumpolar Deep Water across the Antarctic Shelf Break. Geophys. Res. Lett. 42, 432–440 (2015).

    ADS  Google Scholar 

  92. 92.

    Naughten, K. A. et al. Intercomparison of Antarctic ice-shelf, ocean, and sea-ice interactions simulated by MetROMS-iceshelf and FESOM 1.4. Geosci. Model Dev. 11, 1257–1292 (2018).

    ADS  Google Scholar 

  93. 93.

    Wessel, P., Smith, W. H., Scharroo, R., Luis, J. & Wobbe, F. Generic mapping tools: improved version released. Eos 94, 409–410 (2013).

    ADS  Google Scholar 

  94. 94.

    Crameri, F. Geodynamic diagnostics, scientific visualisation and StagLab 3.0. Geosci. Model Dev. 11, 2541–2562 (2018).

    ADS  Google Scholar 

  95. 95.

    Kovesi, P. Good colour maps: how to design them. Preprint at (2015).

  96. 96.

    Zwally, H. J., Giovinetto, M. B., Beckley, M. A. & Saba, J. L. Antarctic and Greenland Drainage Systems. GSFC Cryospheric Sciences Laboratory (2012).

  97. 97.

    Scambos, T. A., Haran, T. M., Fahnestock, M. A., Painter, T. H. & Bohlander, J. Modis-based Mosaic of Antarctica (MOA) data sets: continent-wide surface morphology and snow grain size. Remote Sens. Environ. 111, 242–257 (2007).

    ADS  Google Scholar 

  98. 98.

    Haran, T., Bohlander, J., Scambos, T., Painter, T., and Fahnestock, M. MODIS Mosaic of Antarctica 2008–2009 (MOA2009) Image Map. National Snow and Ice Data Center (2014).

  99. 99.

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

    ADS  CAS  Google Scholar 

  100. 100.

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

    ADS  CAS  Google Scholar 

  101. 101.

    Nagler, T., Rott, H., Hetzenecker, M., Wuite, J. & Potin, P. The Sentinel-1 mission: new opportunities for ice sheet observations. Remote Sens. 7, 9371–9389 (2015).

    ADS  Google Scholar 

  102. 102.

    Rignot, E., Mouginot, J. & Scheuchl, B. Ice flow of the Antarctic Ice Sheet. Science 333, 1427–1430 (2011).

    ADS  CAS  PubMed  Google Scholar 

  103. 103.

    Rignot, E. et al. Recent Antarctic ice mass loss from radar interferometry and regional climate modelling. Nat. Geosci. 1, 106–110 (2008).

    ADS  CAS  Google Scholar 

  104. 104.

    King, M. A. et al. Lower satellite-gravimetry estimates of Antarctic sea-level contribution. Nature 491, 586–589 (2012).

    ADS  CAS  Google Scholar 

  105. 105.

    Helm, V., Humbert, A. & Miller, H. Elevation and elevation change of Greenland and Antarctica derived from CryoSat-2. Cryosphere 8, 1539–1559 (2014).

    ADS  Google Scholar 

  106. 106.

    Martín-Español, A. et al. Spatial and temporal Antarctic Ice Sheet mass trends, glacio-isostatic adjustment, and surface processes from a joint inversion of satellite altimeter, gravity, and GPS data. J. Geophys. Res. 121, 182–200 (2016).

    Google Scholar 

  107. 107.

    Gardner, A. S. et al. Increased West Antarctic and unchanged East Antarctic ice discharge over the last 7 years. Cryosphere 12, 521–547 (2018).

    ADS  Google Scholar 

  108. 108.

    McMillan, M. et al. Increased ice losses from Antarctica detected by CryoSat-2. Geophys. Res. Lett. 41, 3899–3905 (2014).

    ADS  Google Scholar 

  109. 109.

    Velicogna, I. & Wahr, J. Time-variable gravity observations of ice sheet mass balance: Precision and limitations of the GRACE satellite data. Geophys. Res. Lett. 40, 3055–3063 (2013).

    ADS  Google Scholar 

  110. 110.

    Lenaerts, J., van den Broeke, M., van de Berg, W., van Meijgaard, E. & Munneke, P. A new, high-resolution surface mass balance map of Antarctica (1979–2010) based on regional atmospheric climate modeling. Geophys. Res. Lett. 39, L04501 (2012).

    ADS  Google Scholar 

  111. 111.

    Turner, J., Connolley, W. M., Leonard, S., Marshall, G. J. & Vaughan, D. G. Spatial and temporal variability of net snow accumulation over the Antarctic from ECMWF re-analysis project data. Int. J. Climatol. 19, 697–724 (1999).

    Google Scholar 

  112. 112.

    van de Berg, W. J., van den Broeke, M. R., Reijmer, C. H. & van Meijgaard, E. Reassessment of the Antarctic surface mass balance using calibrated output of a regional atmospheric climate model. J. Geophys. Res. 111, D11104 (2006).

    ADS  Google Scholar 

  113. 113.

    Liu, Y. et al. Ocean-driven thinning enhances iceberg calving and retreat of Antarctic ice shelves. Proc. Natl Acad. Sci. USA 112, 3263–3268 (2015).

    ADS  CAS  PubMed  PubMed Central  Google Scholar 

  114. 114.

    Rignot, E., Box, J. E., Burgess, E. & Hanna, E. Mass balance of the Greenland ice sheet from 1958 to 2007. Geophys. Res. Lett. 35, L20502 (2008).

    ADS  Google Scholar 

  115. 115.

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

    ADS  CAS  PubMed  PubMed Central  Google Scholar 

  116. 116.

    Rignot, E. & Kanagaratnam, P. Changes in the velocity structure of the Greenland ice sheet. Science 311, 986–990 (2006).

    ADS  CAS  PubMed  PubMed Central  Google Scholar 

  117. 117.

    Sasgen, I. et al. Timing and origin of recent regional ice-mass loss in Greenland. Earth Planet. Sci. Lett. 333–334, 293–303 (2012).

    ADS  Google Scholar 

  118. 118.

    Box, J. E., Bromwich, D. H. & Bai, L. S. Greenland ice sheet surface mass balance 1991–2000: application of polar MM5 mesoscale model and in situ data. J. Geophys. Res. 109, D16105 (2004).

    ADS  Google Scholar 

  119. 119.

    Wilson, N. J., Straneo, F. & Heimbach, P. Satellite-derived submarine melt rates and mass balance (2011–2015) for Greenland’s largest remaining ice tongues. Cryosphere 11, 2773–2782 (2017).

    ADS  Google Scholar 

  120. 120.

    Bigg, G. R. et al. A century of variation in the dependence of Greenland iceberg calving on ice sheet surface mass balance and regional climate change. Proc. R. Soc. Lond. A 470, 20130662 (2014).

    ADS  CAS  Google Scholar 

Download references


We acknowledge K. Buckley (Victoria University high-performance compute cluster), the Parallel Ice Sheet Model groups at University of Alaska, Fairbanks, the Potsdam Institute for Climate Impact Research and the CMIP community for making their data openly available. PISM is supported by NASA grants NNX13AM16G and NNX13AK27G. This work was funded by contract VUW1501 to N.R.G. from the Royal Society Te Aparangi, with support from the Antarctic Research Centre, Victoria University of Wellington, and GNS Science through the Ministry for Business, Innovation and Employment contract CO5X1001. N.G. was supported by the Natural Sciences and Engineering Research Council of Canada and the Canada Research Chairs programme. J.B. was supported by the MAGIC-DML project through DFG SPP 1158 (RO 4262/1-6). L.D.T. acknowledges support from the NSF Antarctic Glaciology Program (award 1643733).

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Nature thanks F. Pattyn, H. Seroussi and the other anonymous reviewer(s) for their contribution to the peer review of this work.

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N.R.G. devised and carried out the ice-sheet modelling experiments, E.D.K. undertook climate model simulations and N.G. performed the sea-level calculations. K.A.N., J.B. and L.D.T. provided Antarctic basal and surface melt simulations from regional models. All authors contributed to the development of ideas and writing of the manuscript.

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Correspondence to Nicholas R. Golledge.

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Extended data figures and tables

Extended Data Fig. 1 High-latitude air temperature and sea-level anomalies.

a, b, Air (surface) temperature anomalies at 2100 arising from meltwater perturbations from ice sheets simulated under an RCP8.5 climate scenario. Arctic landmasses experience slight cool or warm anomalies, but temperatures over the Arctic ocean warm substantially in the region to the northeast of Greenland (around Svalbard), as far north as the North Pole (a). In the Southern Hemisphere, cooling of up to 3–4 °C occurs across the Southern Ocean and around the margins of Antarctica (b). Temperature anomalies are 30-year means to avoid aliasing short-term variability. c, d, Sea-level changes in the Southern Ocean and around Antarctica computed from the sea-level model (c), and with the addition of sea surface height changes due to ocean temperature changes (d). The thermosteric anomalies are from a 30-year mean to avoid aliasing short-term variability.

Extended Data Fig. 2 Global and regional surface temperature anomalies.

a, b, Surface air (a) and sea surface (b) temperature anomalies at 2100 arising solely from imposed meltwater fluxes, as a percentage of CMIP5 predictions based on emissions forcing but not including meltwater fluxes. c, Zonally and meridionally averaged surface air temperature anomalies for the globe, the Southern Ocean (40–85° S) and over the four largest ice shelves in Antarctica. d, Same as c, but adjusted to give changes relative to 2018.

Extended Data Fig. 3 Antarctic ice-sheet extent under Pliocene conditions.

Shown are results of 5-km-resolution simulations of the Antarctic ice sheet under peak-warmth Pliocene conditions, based on proxy-constrained climate and ocean fields from regional climate modelling54 but using an ice-sheet parameterization identical to that used for the RCP simulations presented in the main paper. The total sea-level-equivalent (SLE) mass loss after 5,000 years is 10.4 m, close to the 11.3 m simulated by a previous study that used ice-shelf hydrofracture and marine ice-cliff instability20, neither of which are used here.

Extended Data Fig. 4 Committed response of West Antarctica.

The extent of grounded ice in West Antarctica at 2100, 2300 and 2500 is illustrated for two emissions pathways (RCP4.5 and RCP8.5) and for experiments in which the climate forcing is held constant from 2020, 2050 or 2100, but without the inclusion of ice–ocean–atmosphere feedbacks. Mass loss in these scenarios illustrates long-term commitments locked in by cumulative forcing up to the point of stabilization. Thwaites Glacier basin retreats in all scenarios, suggesting that the threshold for its stability has already been passed. Contour intervals are 250 m. Black lines show modern coast, for context.

Extended Data Fig. 5 Grounding-line sensitivity and basal-melt parameterization

. Control run (constant year-2000 climatology) and RCP8.5-forced experiments (including ice–ocean–atmosphere feedbacks) for Antarctica (a) and Greenland (b), with and without the incorporation of the sub-grid grounding-line melt scheme. Without the scheme, Antarctic ice volumes are higher in the forced run than with sub-grid melt enabled, but the control run also increases in volume, which suggests that other aspects of model parameterization would need to be optimized to ensure agreement with observational constraints (Extended Data Tables 1 and 2). Greenland simulations are far less affected by the sub-grid melt scheme. The Greenland runs shown all incorporate the evolving surface mass balance and basal traction parameterization (Methods), for clearer comparison between control and perturbed experiments. c, Change in grounded ice volume in Antarctica, compared to control runs, simulated by our ice-sheet model using a range of horizontal grid resolutions (see legend) but otherwise identical parameterization and including the sub-grid grounding-line basal melt scheme. d, Rate of Greenland Ice Sheet mass loss for the best-fitting simulation (dark blue line) compared to simulations in which either a steeper increase in sliding is applied (light blue line) or sliding is maintained at a constant value for the entire run (orange line). Numbers in brackets quantify the change in till friction angle in the piecewise-linear basal traction parameter below −200 m and above 500 m, relative to the ‘No taper’ experiment. Gold boxes show the time span (x axis) and uncertainty (y axis) of empirical data values used as targets during parameter optimization, from sources detailed in Extended Data Tables 1 and 2. e, f, Target melt rates from an empirically constrained99,100 ice-sheet simulation25 (e) are used as inputs to an inverse scheme that solves for a spatially distributed melt factor to translate CMIP5 sea surface temperatures into realistic melt fields (f). This approach greatly improves the representation of ice-shelf basal melting in our simulation compared to previous studies18,20.

Extended Data Fig. 6 Ice-sheet influence on subsurface ocean temperature.

ac, Ocean temperature anomalies by 2100 at 415-m depth from Greenland meltwater flux only (a), Antarctic meltwater flux only (b) and combined meltwater flux from both ice sheets (c). Anomalies are 30-year means to avoid aliasing short-term variability.

Extended Data Fig. 7 Modelled versus measured surface elevation.

ad, Measured values of surface elevation of the Greenland63 (a) and Antarctic62 (b) ice sheets compared to modelled values (c, d) at year 2000. e, f, Differences between the two (modelled minus observed).

Extended Data Fig. 8 Modelled versus measured surface velocity.

ad, Measured values of surface velocity of the Greenland101 (a) and Antarctic102 (b) ice sheets compared to modelled values (c, d) at year 2000. e, f, Differences between the two (modelled minus observed).

Extended Data Table 1 Empirical constraints used to guide Antarctic Ice Sheet parameterization
Extended Data Table 2 Empirical constraints used to guide Greenland Ice Sheet parameterization

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Golledge, N.R., Keller, E.D., Gomez, N. et al. Global environmental consequences of twenty-first-century ice-sheet melt. Nature 566, 65–72 (2019).

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