Abstract
The Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) is the primary effort of CMIP6 (Coupled Model Intercomparison Project–Phase 6) focusing on ice sheets, designed to provide an ensemble of process-based projections of the ice-sheet contribution to sea-level rise over the twenty-first century. However, the behavior of the Antarctic Ice Sheet beyond 2100 remains largely unknown: several instability mechanisms can develop on longer time scales, potentially destabilizing large parts of Antarctica. Projections of Antarctic Ice Sheet evolution until 2300 are presented here, using an ensemble of 16 ice-flow models and forcing from global climate models. Under high-emission scenarios, the Antarctic sea-level contribution is limited to less than 30 cm sea-level equivalent (SLE) by 2100, but increases rapidly thereafter to reach up to 4.4 m SLE by 2300. Simulations including ice-shelf collapse lead to an additional 1.1 m SLE on average by 2300, and can reach 6.9 m SLE. Widespread retreat is observed on that timescale in most West Antarctic basins, leading to a collapse of large sectors of West Antarctica by 2300 in 30%–40% of the ensemble. While the onset date of retreat varies among ice models, the rate of upstream propagation is highly consistent once retreat begins. Calculations of sea-level contribution including water density corrections lead to an additional ∼10% sea level and up to 50% for contributions accounting for bedrock uplift in response to ice loading. Overall, these results highlight large sea-level contributions from Antarctica and suggest that the choice of ice sheet model remains the leading source of uncertainty in multi-century projections.
| Original language | English |
|---|---|
| Article number | e2024EF004561 |
| Number of pages | 44 |
| Journal | Earth's Future |
| Volume | 12 |
| Issue number | 9 |
| DOIs | |
| Publication status | Published - 4 Sept 2024 |
Bibliographical note
Funding Information:We thank the Climate and Cryosphere (CliC) effort, which provided support for ISMIP6 through sponsoring of workshops, hosting the ISMIP6 website and wiki, and promoted ISMIP6. We acknowledge the World Climate Research Programme, which, through its Working Group on Coupled Modeling, coordinated and promoted CMIP5 and CMIP6. We thank the climate modeling groups for producing and making available their model output, the Earth System Grid Federation (ESGF) for archiving the CMIP data and providing access, the University at Buffalo for ISMIP6 data distribution and upload, and the multiple funding agencies who support CMIP5 and CMIP6 and ESGF. We thank the ISMIP6 steering committee, the ISMIP6 model selection group and ISMIP6 data set preparation group for their continuous engagement in defining ISMIP6. This is ISMIP6 contribution No 33. H\u00E9l\u00E8ne Seroussi was supported by grants from NASA Cryospheric Science Program (#80NSSC21K1939 and #80NSSC22K0383) and the Novo Nordisk Foundation under the Challenge Programme 2023\u2014Grant number NNF23OC00807040. Jake Twarog was supported by a URAD grant from Dartmouth College's Undergraduate Advising & Research program. Resources supporting this work were provided by the NASA High\u2010End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center. Tyler Pelle was supported by grants from the NASA Cryospheric Science Program (#80NSSC22K0387), the NSF (#OPP\u20102114454), and the Cecil H. and the Ida M. Green Foundation for Earth Sciences at the Institute of Geophysics and Planetary Physics at Scripps Institution of Oceanography. WHL was supported by the NSF National Center for Atmospheric Research, which is a major facility sponsored by the U.S. National Science Foundation under Cooperative Agreement No. 1852977. Support for Xylar Asay\u2010Davis, Holly Kyeore Han, Trevor Hillebrand, and Matthew Hoffman was provided through the Scientific Discovery through Advanced Computing (SciDAC) and Early Career Research programs, funded by the US Department of Energy (DOE), Office of Science, Advanced Scientific Computing Research and Biological and Environmental Research programs. MALI simulations were performed on machines at the National Energy Research Scientific Computing Center, a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE\u2010AC02\u201005CH11231 using NERSC award using NERSC awards ERCAP0024081 and ERCAP0023782. Heiko Goelzer has received funding from the European Union's Horizon 2020 Research and Innovation Programme under Grant Agreement No. 869304, PROTECT and from the Research Council of Norway under project 343397 (CLIM2Ant). Rupert Gladstone was supported by Academy of Finland Grants 322430 and 355572, and by the Finnish Ministry of Education and Culture and CSC\u2014IT Center for Science (Decision diary number OKM/10/524/2022). Chen Zhao, Yu Wang, and Ben Galton\u2010Fenzi received grant funding from the Australian Government as part of the Antarctic Science Collaboration Initiative program (ASCI000002). Chen Zhao is the recipient of an Australian Research Council Discovery Early Career Researcher Award (project number DE240100267) funded by the Australian Government. Thomas Zwinger was supported by the Academy of Finland Grant 286587. UTAS_ElmerIce simulations were enabled by computational resources provided by CSC\u2010IT Center for Science Ltd. Ralf Greve was supported by Japan Society for the Promotion of Science (JSPS) KAKENHI Grant JP16H02224, JP17H06104, and JP17H06323. Alexander Robinson received funding from the European Union (ERC, FORCLIMA, 101044247). Marisa Montoya received funding from the Spanish State Research Agency (MARINE, PID2020\u2010117768RB\u2010I00). Jorge Alvarez\u2010Solas received funding from the Spanish State Research Agency (ICEAGE, PID2019\u2010110714RA\u2010I00). Javier Blasco received funding from the Dutch Research Council (HiRISE, OCENW.GROOT.2019.091). Torsten Albrecht was funded by the German climate modeling project PalMod (FKZ: 01LP1925D and 01LP2305B) supported by the German Federal Ministry of Education and Research (BMBF) as a Research for Sustainability initiative (FONA). Torsten Albrecht acknowledges support by OCEAN:ICE, which is co\u2010funded by the European Union, Horizon Europe Funding Programme for research and innovation under grant agreement Nr. 101060452 and by UK Research and Innovation. This is O:I contribution number 8. Ann Kristin Klose, Ronja Reese, Julius Garbe and Torsten Albrecht gratefully acknowledge the European Regional Development Fund (ERDF), the German Federal Ministry of Education and Research and the Land Brandenburg for supporting this project by providing resources on the high performance computer system at the Potsdam Institute for Climate Impact Research (PIK). Development of PISM is supported by NASA Grants 20\u2010CRYO2020\u20100052 and 80NSSC22K0274 and NSF Grant OAC\u20102118285. Ann Kristin Klose acknowledges support by the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 820575 (TiPACCs) and No. 869304 (PROTECT). Julius Garbe, Ronja Reese, David Chandler, Petra Langebroek, Beno\u00EEt Urruty, Fabien Gillet\u2010Chaulet, Pierre Mathiot, Sainan Sun, G. Hilmar Gudmundsson and Nicolas Jourdain were supported by the European Union's Horizon 2020 Research and Innovation Programme under Grant Agreement No. 820575 (TiPACCs). Petra Langebroek was also supported by the Research Council of Norway through the Centre of Excellence iC3 (project number 332635). Justine Caillet, Fabien Gillet\u2010Chaulet, Pierre Mathiot and Nicolas Jourdain were supported by the French National Research Agency (ANR) under grant ANR\u201019\u2010CE01\u20100015 (EIS). IGE team work was granted access to the high\u2010performance computing (HPC) resources of TGCC under allocation A0140106066 attributed by GENCI. Constantijn J. Berends and Violaine Coulon were supported by PROTECT, receiving funding from the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 869304. This is PROTECT contribution number 113. Jorge Bernales was funded by NWO, Grant OCENW.KLEIN.515. UFEMISM simulations were carried out on the Dutch National supercomputer Snellius, hosted at SURF. Nick Golledge and Dan Lowry are supported by Antarctic Science Platform (ANTA1801) and Our Changing Coast (RTVU2206) grants from the New Zealand Ministry of Business, Innovation, and Employment. Computational resources to perform Kori simulations have been provided by the Consortium des \u00C9quipements de Calcul Intensif (C\u00C9CI), funded by the Fonds de la Recherche Scientifique de Belgique (F.R.S.\u2010FNRS) under Grant 2.5020.11 and by the Walloon Region. Philippe Huybrechts and Jonas Van Breedam acknowledge support from the Research Foundation Flanders (FWO Vlaanderen) with Grant G091820N. Roderik van de Wal received funding from the Dutch Polar Program (Grant: ALWPP.2019.003).
Funding Information:
We thank the Climate and Cryosphere (CliC) effort, which provided support for ISMIP6 through sponsoring of workshops, hosting the ISMIP6 website and wiki, and promoted ISMIP6. We acknowledge the World Climate Research Programme, which, through its Working Group on Coupled Modeling, coordinated and promoted CMIP5 and CMIP6. We thank the climate modeling groups for producing and making available their model output, the Earth System Grid Federation (ESGF) for archiving the CMIP data and providing access, the University at Buffalo for ISMIP6 data distribution and upload, and the multiple funding agencies who support CMIP5 and CMIP6 and ESGF. We thank the ISMIP6 steering committee, the ISMIP6 model selection group and ISMIP6 data set preparation group for their continuous engagement in defining ISMIP6. This is ISMIP6 contribution No 33. H\u00E9l\u00E8ne Seroussi was supported by grants from NASA Cryospheric Science Program (#80NSSC21K1939 and #80NSSC22K0383) and the Novo Nordisk Foundation under the Challenge Programme 2023\u2014Grant number NNF23OC00807040. Jake Twarog was supported by a URAD grant from Dartmouth College's Undergraduate Advising & Research program. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center. Tyler Pelle was supported by grants from the NASA Cryospheric Science Program (#80NSSC22K0387), the NSF (#OPP-2114454), and the Cecil H. and the Ida M. Green Foundation for Earth Sciences at the Institute of Geophysics and Planetary Physics at Scripps Institution of Oceanography. WHL was supported by the NSF National Center for Atmospheric Research, which is a major facility sponsored by the U.S. National Science Foundation under Cooperative Agreement No. 1852977. Support for Xylar Asay-Davis, Holly Kyeore Han, Trevor Hillebrand, and Matthew Hoffman was provided through the Scientific Discovery through Advanced Computing (SciDAC) and Early Career Research programs, funded by the US Department of Energy (DOE), Office of Science, Advanced Scientific Computing Research and Biological and Environmental Research programs. MALI simulations were performed on machines at the National Energy Research Scientific Computing Center, a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE-AC02-05CH11231 using NERSC award using NERSC awards ERCAP0024081 and ERCAP0023782. Heiko Goelzer has received funding from the European Union's Horizon 2020 Research and Innovation Programme under Grant Agreement No. 869304, PROTECT and from the Research Council of Norway under project 343397 (CLIM2Ant). Rupert Gladstone was supported by Academy of Finland Grants 322430 and 355572, and by the Finnish Ministry of Education and Culture and CSC\u2014IT Center for Science (Decision diary number OKM/10/524/2022).
Publisher Copyright:
© 2024. The Author(s).