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Antarctic calving loss rivals ice-shelf thinning

Abstract

Antarctica’s ice shelves help to control the flow of glacial ice as it drains into the ocean, meaning that the rate of global sea-level rise is subject to the structural integrity of these fragile, floating extensions of the ice sheet1,2,3. Until now, data limitations have made it difficult to monitor the growth and retreat cycles of ice shelves on a large scale, and the full impact of recent calving-front changes on ice-shelf buttressing has not been understood. Here, by combining data from multiple optical and radar satellite sensors, we generate pan-Antarctic, spatially continuous coastlines at roughly annual resolution since 1997. We show that from 1997 to 2021, Antarctica experienced a net loss of 36,701 ± 1,465 square kilometres (1.9 per cent) of ice-shelf area that cannot be fully regained before the next series of major calving events, which are likely to occur in the next decade. Mass loss associated with ice-front retreat (5,874 ± 396 gigatonnes) has been approximately equal to mass change owing to ice-shelf thinning over the past quarter of a century (6,113 ± 452 gigatonnes), meaning that the total mass loss is nearly double that which could be measured by altimetry-based surveys alone. We model the impacts of Antarctica’s recent coastline evolution in the absence of additional feedbacks, and find that calving and thinning have produced equivalent reductions in ice-shelf buttressing since 2007, and that further retreat could produce increasingly significant sea-level rise in the future.

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Fig. 1: Antarctic coastal change since 1997.
Fig. 2: Cumulative area change since 1997.
Fig. 3: Calving history of Antarctica’s largest ice shelves.
Fig. 4: Modelled instantaneous response to forcing.

Data availability

We use velocity data from ITS_LIVE51, which is available at https://its-live.jpl.nasa.gov/ and MEaSUREs InSAR-Based Antarctica Ice Velocity Map, Version 252, which is available at https://doi.org/10.5067/D7GK8F5J8M8R. Static ice-thickness data are primarily from BedMachine Antarctica Version 253, which is available at https://doi.org/10.5067/E1QL9HFQ7A8M. We also use surface elevation data from REMA54 (https://www.pgc.umn.edu/data/rema/), Bedmap255 (https://www.bas.ac.uk/project/bedmap-2/), Antarctic 1-km digital elevation model from Combined ERS-1 Radar and ICESat Laser Satellite Altimetry, Version 156 (https://doi.org/10.5067/H0FQ1KL9NEKM) and Radarsat Antarctic Mapping Project Digital Elevation Model, Version 257 (https://doi.org/10.5067/8JKNEW6BFRVD). Ice-shelf masks are adapted from MEaSUREs Antarctic Boundaries for IPY 2007–2009 from Satellite Radar, Version 258 (https://doi.org/10.5067/AXE4121732AD). Ice-shelf-thickness time series36 are available at http://its-live-data.s3.amazonaws.com/height_change/Antarctica/Floating/ANT_G1920V01_IceShelfMelt.nc. Radarsat-derived coastlines59 are available at https://asf.alaska.edu/data-sets/derived-data-sets/ramp/ramp-get-ramp-data/, coastlines from MODIS Mosaic of Antarctica60 are available at https://doi.org/10.5067/68TBT0CGJSOJ and coastlines from the fast-ice dataset61 are available at https://doi.org/10.26179/5d267d1ceb60c. Sentinel 1b-based mosaics used in this work are available at http://seaice.dk/. Our final, processed ice-shelf-thickness and -mass time series data are presented in Supplementary Table 1 and are also available in .mat format at https://github.com/chadagreene/ice-shelf-geometry. The coastline data presented in this work are available as plain-text files of ice-sheet outlines and also as binary grids at 240-m resolution in .mat format at https://doi.org/10.5281/zenodo.5903643.

Code availability

Analysis and figure generation were performed in MATLAB, with functions from Antarctic Mapping Tools for MATLAB73 and the Climate Data Toolbox for MATLAB74. All code that was developed for this work to generate coastlines, analyse the data and produce the figures is available at https://github.com/chadagreene/ice-shelf-geometry. Ice-shelf surface elevation time series were processed with the Cryosphere Altimetry Processing Toolkit, which is available at https://doi.org/10.5281/zenodo.3665785. The ISSM and GEMB models used in this work are open-source and publicly available at https://issm.jpl.nasa.gov.

References

  1. Fox-Kemper, B. et al. in Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change,Ch.9 (eds Masson-Delmotte, V. et al.) 1211–1362 (Cambridge Univ. Press, 2021).

  2. Reese, R., Gudmundsson, G. H., Levermann, A. & Winkelmann, R. The far reach of ice-shelf thinning in Antarctica. Nat. Clim. Change 8, 53–57 (2018).

    Article  ADS  Google Scholar 

  3. Fürst, J. J. et al. The safety band of Antarctic ice shelves. Nat. Clim. Change 6, 479–482 (2016).

    Article  ADS  Google Scholar 

  4. Borstad, C. P. et al. A damage mechanics assessment of the Larsen B ice shelf prior to collapse: toward a physically-based calving law. Geophys. Res. Lett. 39, L18502 (2012).

    Article  ADS  Google Scholar 

  5. Scambos, T. A. et al. Ice shelf disintegration by plate bending and hydro-fracture: satellite observations and model results of the 2008 Wilkins ice shelf break-ups. Earth Planet. Sci. Lett. 280, 51–60 (2009).

    CAS  Article  ADS  Google Scholar 

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

    CAS  Article  ADS  Google Scholar 

  7. Nowicki, S. et al. Experimental protocol for sea level projections from ISMIP6 stand-alone ice sheet models. Cryosphere 14, 2331–2368 (2020).

    Article  ADS  Google Scholar 

  8. Pattyn, F. et al. The Greenland and Antarctic ice sheets under 1.5 °C global warming. Nat. Clim. Change 8, 1053–1061 (2018).

    Article  ADS  Google Scholar 

  9. Seroussi, H. et al. ISMIP6 Antarctica: a multi-model ensemble of the Antarctic ice sheet evolution over the 21st century. Cryosphere 14, 3033–3070 (2020).

    Article  ADS  Google Scholar 

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

    CAS  PubMed  Article  ADS  Google Scholar 

  11. Edwards, T. L. et al. Revisiting Antarctic ice loss due to marine ice-cliff instability. Nature 566, 58–64 (2019).

    CAS  PubMed  Article  ADS  Google Scholar 

  12. Bassis, J. N., Berg, B., Crawford, A. J. & Benn, D. I. Transition to marine ice cliff instability controlled by ice thickness gradients and velocity. Science 372, 1342–1344 (2021).

    CAS  PubMed  Article  ADS  Google Scholar 

  13. Crawford, A. J. et al. Marine ice-cliff instability modeling shows mixed-mode ice-cliff failure and yields calving rate parameterization. Nat. Commun. 12, 2701 (2021).

    CAS  PubMed  PubMed Central  Article  ADS  Google Scholar 

  14. Clerc, F., Minchew, B. M. & Behn, M. D. Marine ice cliff instability mitigated by slow removal of ice shelves. Geophys. Res. Lett. 46.21, 12108–12116 (2019).

    Article  Google Scholar 

  15. Cape, M. R., Vernet, M., Kahru, M. & Spreen, G. Polynya dynamics drive primary production in the Larsen A and B embayments following ice shelf collapse. J. Geophys. Res. Oceans 119, 572–594 (2014).

    Article  ADS  Google Scholar 

  16. Campagne, P. et al. Glacial ice and atmospheric forcing on the Mertz Glacier Polynya over the past 250 years. Nat. Commun. 6, 6642 (2015).

    CAS  PubMed  Article  ADS  Google Scholar 

  17. Clarke, A. et al. Climate change and the marine ecosystem of the western Antarctic Peninsula. Phil. Trans. R. Soc. B 362, 149–166 (2007).

  18. Grosfeld, K., Schröder, M., Fahrbach, E., Gerdes, R. & Mackensen, A. How iceberg calving and grounding change the circulation and hydrography in the Filchner Ice Shelf–Ocean System. J. Geophys. Res. Oceans 106, 9039–9055 (2001).

    Article  ADS  Google Scholar 

  19. Silva, T. A. M., Bigg, G. R. & Nicholls, K. W. Contribution of giant icebergs to the Southern Ocean freshwater flux. J. Geophys. Res. Oceans 111, C03004 (2006).

  20. Stern, A. A., Adcroft, A. & Sergienko, O. The effects of Antarctic iceberg calving‐size distribution in a global climate model. J. Geophys. Res. Oceans 121, 5773–5788 (2016).

    Article  ADS  Google Scholar 

  21. Yoon, S.-T. et al. Ice front retreat reconfigures meltwater-driven gyres modulating ocean heat delivery to an Antarctic ice shelf. Nat. Commun. 13, 306 (2022).

    CAS  PubMed  PubMed Central  Article  ADS  Google Scholar 

  22. Gutt, J. et al. Biodiversity change after climate-induced ice-shelf collapse in the Antarctic. Deep Sea Res. II 58, 74–83 (2011).

    Article  ADS  Google Scholar 

  23. Adusumilli, S., Fricker, H. A., Medley, B., Padman, L. & Siegfried., M. R. Interannual variations in meltwater input to the Southern Ocean from Antarctic ice shelves. Nat. Geosci. 13, 616–620 (2020).

    CAS  PubMed  PubMed Central  Article  ADS  Google Scholar 

  24. Mohajerani, Y., Wood, M., Velicogna, I. & Rignot, E. Detection of glacier calving margins with convolutional neural networks: a case study. Remote Sensing 2019, 74 (2019).

  25. Miles, B. W. J., Stokes, C. R. & Jamieson, S. S. R. Pan–ice-sheet glacier terminus change in East Antarctica reveals sensitivity of Wilkes Land to sea-ice changes. Sci. Adv. 2, e1501350 (2016).

  26. Greene, C. A., Young, D. A., Gwyther, D. E., Galton-Fenzi, B. K. & Blankenship, D. D. Seasonal dynamics of Totten Ice Shelf controlled by sea ice buttressing. Cryosphere 12, 2869–2882 (2018).

    Article  ADS  Google Scholar 

  27. Baumhoer, C. A., Dietz, A. J., Kneisel, C., Paeth, H. & Kuenzer, C. Environmental drivers of circum-Antarctic glacier and ice shelf front retreat over the last two decades. Cryosphere 15, 2357–2381 (2021).

  28. Scambos, T. et al. Calving and ice-shelf break-up processes investigated by proxy: Antarctic tabular iceberg evolution during northward drift. J. Glaciol. 54, 579–591 (2008).

  29. Lazzara, M. A., Jezek, K. C., Scambos, T. A., MacAyeal, D. R. & Van der Veen, C. J. On the recent calving of icebergs from the Ross Ice Shelf. Polar Geogr. 23, 201–212 (1999).

  30. MacAyeal, D. R. et al. Tabular iceberg collisions within the coastal regime. J. Glaciol. 54, 371–386 (2008).

    Article  ADS  Google Scholar 

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

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

    CAS  PubMed  Article  ADS  Google Scholar 

  33. 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).

    CAS  PubMed  PubMed Central  Article  ADS  Google Scholar 

  34. Qi, M. et al. A 15-year circum-Antarctic iceberg calving dataset derived from continuous satellite observations. Earth Syst. Sci. Data 13, 4583–4601 (2021).

    Article  ADS  Google Scholar 

  35. Ferrigno, J. G. & Gould, W. G. Substantial changes in the coastline of Antarctica revealed by satellite imagery. Polar Rec. 23, 577–583 (1987).

  36. Paolo, F., Gardner, A. S., Greene, C. A. & Schlegel, N. J. MEaSUREs ITS_LIVE Antarctic Ice Shelf Height Change and Basal Melt Rates, Version 1 (2022); NASA https://doi.org/10.5067/SE3XH9RXQWAM

  37. Larour, E., Seroussi, H., Morlighem, M. & Rignot, E. Continental scale, high order, high spatial resolution, ice sheet modeling using the Ice Sheet System Model (ISSM). J. Geophys. Res. Earth Surf. 117, F01022 (2012).

  38. Gudmundsson, G. H., Paolo, F. S., Adusumilli, S. & Fricker, H. A. Instantaneous Antarctic ice sheet mass loss driven by thinning ice shelves. Geophys. Res. Lett. 46, 13903–13909 (2019).

    Article  ADS  Google Scholar 

  39. Sun, S. et al. Antarctic ice sheet response to sudden and sustained ice-shelf collapse (ABUMIP). J. Glaciol. 66, 891–904 (2020).

  40. De Rydt, J., Reese, R., Paolo, F. S. & Gudmundsson, G. H. Drivers of Pine Island Glacier speed-up between 1996 and 2016. Cryosphere 15, 113–132 (2021).

    Article  ADS  Google Scholar 

  41. Joughin, I., Shapero, D., Smith, B., Dutrieux, P. & Barham, M. Ice-shelf retreat drives recent Pine Island Glacier speedup. Sci. Adv. 7, eabg3080 (2021).

  42. Schlegel, N.-J. et al. Exploration of Antarctic Ice Sheet 100-year contribution to sea level rise and associated model uncertainties using the ISSM framework. Cryosphere 12, 3511–3534 (2018).

    Article  ADS  Google Scholar 

  43. Robel, A. A. & Banwell, A. F. A speed limit on ice shelf collapse through hydrofracture. Geophys. Res. Lett. 46, 12092–12100 (2019).

    Article  ADS  Google Scholar 

  44. Goldberg, D. N., Heimbach, P., Joughin, I. & Smith, B. Committed retreat of Smith, Pope, and Kohler Glaciers over the next 30 years inferred by transient model calibration. Cryosphere 9, 2429–2446 (2015).

    Article  ADS  Google Scholar 

  45. Lilien, D. A., Joughin, I., Smith, B. & Gourmelen, N. Melt at grounding line controls observed and future retreat of Smith, Pope, and Kohler glaciers. Cryosphere 13, 2817–2834 (2019).

    Article  ADS  Google Scholar 

  46. Pattyn, F., Huyghe, A., De Brabander, S. & De Smedt, B. Role of transition zones in marine ice sheet dynamics. J. Geophys. Res. Earth Surf. 111, eabg3080 (2006).

  47. Edwards, T. L. et al. Projected land ice contributions to twenty-first-century sea level rise. Nature 593, 74–82 (2021).

    CAS  PubMed  Article  ADS  Google Scholar 

  48. Massom, R. A. et al. External influences on the Mertz Glacier Tongue East Antarctica in the decade leading up to its calving in 2010. J. Geophys. Res. Earth Surf. 120, 490–506 (2015).

  49. Fricker, H. A., Young, N. W., Allison, I. & Coleman, R. Iceberg calving from the Amery ice shelf, East Antarctica. Ann. Glaciol. 34, 241–246 (2002).

  50. Walker, C. C., Becker, M. K. & Fricker, H. A. A high resolution, three‐dimensional view of the D‐28 calving event from Amery Ice Shelf with ICESat‐2 and satellite imagery. Geophys. Res. Lett. 483, e2020GL091200 (2021).

    ADS  Google Scholar 

  51. Gardner, A. S., Fahnestock, M. A. & Scambos, T. A. ITS_LIVE Regional Glacier and Ice Sheet Surface Velocities (National Snow and Ice Data Center, 2019); https://doi.org/10.5067/6II6VW8LLWJ7

  52. Rignot, E., Mouginot, J. & Scheuchl, B. MEaSUREs InSAR-Based Antarctica Ice Velocity Map, Version 2 (NASA National Snow and Ice Data Center Distributed Active Archive Center, 2017); https://doi.org/10.5067/D7GK8F5J8M8R

  53. Morlighem, M. MEaSUREs BedMachine Antarctica, Version 2 (NASA National Snow and Ice Data Center Distributed Active Archive Center, 2020); https://doi.org/10.5067/E1QL9HFQ7A8M

  54. Howat, I. M., Porter, C., Smith, B. E., Noh, M. J. & Morin, P. The reference elevation model of Antarctica. Cryosphere 13, 665–674 (2019).

    Article  ADS  Google Scholar 

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

  56. Bamber, J., Gomez-Dans, J. L. & Griggs, J. A. Antarctic 1 km Digital Elevation Model (DEM) from Combined ERS-1 Radar and ICESat Laser Satellite Altimetry, Version 1 (NASA National Snow and Ice Data Center Distributed Active Archive Center, 2009); https://doi.org/10.5067/H0FQ1KL9NEKM

  57. Liu, H., Jezek, K. C., Li, B. & Zhao, Z. Radarsat Antarctic Mapping Project Digital Elevation Model, Version 2 (NASA National Snow and Ice Data Center Distributed Active Archive Center, 2015); https://doi.org/10.5067/8JKNEW6BFRVD

  58. Mouginot, J., Scheuchl, B. & Rignot, E. MEaSUREs Antarctic Boundaries for IPY 2007–2009 from Satellite Radar, Version 2 (NASA National Snow and Ice Data Center Distributed Active Archive Center, 2017; https://doi.org/10.5067/AXE4121732AD

  59. Liu, H. & Jezek, K. A complete high-resolution coastline of Antarctica extracted from orthorectified radarsat SAR imagery. Photogramm. Eng. Remote Sensing 70, 605–616 (2004).

  60. Haran, T., Bohlander, J., Scambos, T., Painter, T. & Fahnestock, M. MODIS Mosaic of Antarctica Image Map, Version 1 (NASA National Snow and Ice Data Center Distributed Active Archive Center, 2019); https://doi.org/10.5067/68TBT0CGJSOJ

  61. Fraser, A. D. et al. High-resolution mapping of circum-Antarctic landfast sea ice distribution, 2000–2018. Earth Syst. Sci. Data 12, 2987–2999 (2020).

  62. Walker, C. C. et al. Iceberg, right ahead!: The surprising and ongoing collapse of an East Antarctic ice shelf in response to changes in the ocean environment. In AGU Fall Meeting Abstracts abstr. C13A-06 (AGU, 2019).

  63. MacGregor, J. A., Catania, G. A., Markowski, M. S. & Andrews., A. G. Widespread rifting and retreat of ice-shelf margins in the eastern Amundsen Sea Embayment between 1972 and 2011. J. Glaciol. 58, 458–466 (2012).

    Article  ADS  Google Scholar 

  64. Miles, B. W. J. et al. Intermittent structural weakening and acceleration of the Thwaites Glacier Tongue between 2000 and 2018. J. Glaciol. 66, 485–495 (2020).

    Article  ADS  Google Scholar 

  65. Lhermitte, S. et al. Damage accelerates ice shelf instability and mass loss in Amundsen Sea Embayment. Proc. Natl Acad. Sci. USA 117, 24735–24741 (2020).

    CAS  PubMed  PubMed Central  Article  ADS  Google Scholar 

  66. Taylor, J. Introduction to Error Analysis, the Study of Uncertainties in Physical Measurements 2nd edn (University Science Books, 1997).

  67. Morlighem, M. E. et al. Spatial patterns of basal drag inferred using control methods from a full-Stokes and simpler models for Pine Island Glacier, West Antarctica. Geophys. Res. Lett. 37, L14502 (2010).

    Article  ADS  Google Scholar 

  68. Seroussi, H. et al. Dependence of Greenland Ice Sheet projections on its thermal regime. J. Glaciol. 59, 1024–1034 (2013).

  69. Blatter, H. Velocity and stress-fields in grounded glaciers: a simple algorithm for including deviatoric stress gradients. J. Glaciol. 41, 333–344 (1995).

    Article  ADS  Google Scholar 

  70. Pattyn, F. A new three-dimensional higher-order thermomechanical ice sheet model: basic sensitivity, ice stream development, and ice flow across subglacial lakes. J. Geophys. Res. 108, 2382 (2003).

    Article  ADS  Google Scholar 

  71. MacAyeal, D. R. Large-scale ice flow over a viscous basal sediment. Theory and application to Ice Stream B, Antarctica. J. Geophys. Res. 94, 4071–4087 (1989).

    Article  ADS  Google Scholar 

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

  73. Greene, C. A., Gwyther, D. E. & Blankenship, D. D. Antarctic mapping tools for MATLAB. Comput. Geosci. 104, 151–157 (2017).

  74. Greene, C. A. et al. The Climate Data Toolbox for MATLAB. Geochem. Geophys. Geosyst. 20, 3774–3781 (2019).

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Acknowledgements

We thank ESA/Copernicus and R. Saldo of DTU Space/Technical University of Denmark for making Sentinel 1 mosaics available via http://seaice.dk. This research was supported by the NASA Postdoctoral Program, along with the NASA Cryospheric Science, Sea Level Change Team, and Modeling, Analysis and Prediction (MAP) Programs, and was conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration ©2022 All rights reserved. This project received grant funding from the Australian Government as part of the Antarctic Science Collaboration Initiative program. We gratefully acknowledge computational resources and support from the NASA Advanced Supercomputing Division.

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Contributions

C.A.G. and A.S.G. conceived of the study. A.D.F. compiled satellite imagery into mosaics and performed coastline delineation. C.A.G. wrote the code to generate velocity-constrained composite coastlines from multiple sources. N.-J.S. performed modelling experiments. C.A.G. analysed all observational and model data, generated all figures and wrote the first draft of the manuscript. All authors contributed to writing and revising the final manuscript.

Corresponding author

Correspondence to Chad A. Greene.

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Nature thanks Bertie Miles, Kiya Riverman and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Peer reviewer reports are available.

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Extended data figures and tables

Extended Data Fig. 1 Antarctic coastal change since 1997 (continued).

The coastline evolution over the past quarter of a century, shown for selected regions that do not appear in Fig. 1.

Extended Data Fig. 2 Ice shelf mass change since 1997.

The mass imbalance of ice shelves in the blue triangles is dominated by coastal processes, while the balance of only a few ice shelves, mostly located in the Amundsen Sea Embayment, are dominated by thinning. Marker colour corresponds to the central longitude of each ice shelf, and marker area scales with ice-shelf area.

Extended Data Fig. 3 Gridded datasets.

To quantify changes at the ice-sheet margins, where publicly available velocity and thickness datasets may not reach the maximum observed extents of the ice sheet, we combine all available data, then extrapolate thickness, velocity, and a mask of ice-shelf names in the direction of ice flow. Although the resulting grids fill the entire map, we only use thickness and velocity data close to the Antarctic periphery, wherever ice has been observed in at least one of the 24 mappings since 1997.

Extended Data Fig. 4 Iceberg A76 mass estimation.

Weeks after our March 2021 annual pan-Antarctic coastline mapping, the Ronne Ice Shelf calved the 4320 km2 iceberg A76. By considering changes in area and mass that have occurred between each of our 24 consecutive mappings, we estimate that iceberg A76 took 1,002 Gt of ice from Ronne Ice Shelf.

Extended Data Fig. 5 Steady-state calving-flux calculation.

To obtain steady-state calving flux, we calculate pixel centre locations (x1,y1) of a 240-m resolution grid after one year of ice displacement. We use (x1,y1) as query points to linearly interpolate a binary ice mask, which gives the fraction of each grid cell that is still within the initial mask after a year of displacement. Calving flux is calculated by multiplying the fraction of ice that has calved after a year of displacement by the area, thickness, and density of ice in each grid cell.

Extended Data Fig. 6 Measured and modelled grounding-line flux.

All sensitivity measurements described in this manuscript present grounding-line-flux measurements relative to the control values shown here. Marker area scales with ice-shelf area and marker corresponds to the central longitude of each ice shelf.

Extended Data Fig. 7 Comparison to ref. 38.

To help validate the ice-sheet model, we replicate the results from Fig. S12 of ref.  38. This figure shows the instantaneous velocity response resulting from step change in thickness from 2010 to 2017 observations.

Supplementary information

Supplementary Information

Time series of observed ice-shelf area and grounding-line-flux responses to calving.

Peer Review File

Supplementary Table 1

Ice-shelf-mass and -area time series.

Supplementary Videos

This zip file contains animations of observed calving front change, and ice-sheet response to hypothetical calving.

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Greene, C.A., Gardner, A.S., Schlegel, NJ. et al. Antarctic calving loss rivals ice-shelf thinning. Nature 609, 948–953 (2022). https://doi.org/10.1038/s41586-022-05037-w

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