Projecting Antarctica's contribution to future sea level rise from basal ice shelf melt using linear response functions of 16 ice sheet models (LARMIP-2)

• Published in: Earth System Dynamics
• Main Authors: Levermann, Anders, Winkelmann, Ricarda, Albrecht, Torsten, Goelzer, Heiko, Golledge, Nicholas R., Greve, Ralf, Huybrechts, P., Jordan, James R., Leguy, Gunter R., Martin, Daniel F., Morlighem, Mathieu, PATTYN, FRANK, Pollard, David, Quiquet, Aurélien, Rodehacke, Christian B., Seroussi, Hélène, Sutter, Johannes, ZHANG, Tong, Van Breedam, Jonas, Calov, Reinhard, DeConto, Robert M., Dumas, Christophe, Garbe, Julius, Hilmar Gudmundsson, G. Hilmar, Hoffman, Matthew J., Humbert, Angelika, Kleiner, Thomas, Lipscomb, William H., Meinshausen, Malte, Ng, Esmond G., Nowicki, Sophie M.J., Perego, Mauro, Price, Stephen F., Saito, Fuyuki, Schlegel, Nicole Jeanne, Sun, Sainan, Van De Wal, Roderick S.W.
• Other Authors: Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Modélisation du climat (CLIM), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), 01LP1511B National Science Foundation, NSF: 1739031, 1852977 U.S. Department of Energy, USDOE: DE-AC02-05CH11231 National Aeronautics and Space Administration, NASA National Center for Atmospheric Research, NCAR Office of Science, SC Biological and Environmental Research, BER National Energy Research Scientific Computing Center, NERSC Natural Environment Research Council, NERC: NE/R000824/1 European Research Council, ERC: 610055, ICE2ICE Deutsche Forschungsgemeinschaft, DFG: LE1448/6-1, LE1448/7-1 Leibniz-Gemeinschaft Japan Society for the Promotion of Science, KAKEN: JP16H02224, JP17H06104, JP17H06323 Bundesministerium für Bildung und Forschung, BMBF Ministerie van Onderwijs, Cultuur en Wetenschap, OCW: 024.002.001 Seventh Framework Programme, FP7 Netherlands Earth System Science Centre, NESSC, Ralf Greve was supported by the Japan Society for the Promotion of Science (JSPS) under KAKENHI grant nos. JP16H02224, JP17H06104, and JP17H06323., The material provided for the CISM model is based upon work supported by the National Center for Atmospheric Research, which is a major facility sponsored by the National Science Foundation under cooperative agreement no. 1852977. Computing and data storage resources, including the Cheyenne supercomputer (https://www2.cisl.ucar.edu/resources/ computational-systems/cheyenne, last access: 6 January 2020), were provided by the Computational and Information Systems Laboratory (CISL) at NCAR., Torsten Albrecht was supported by the Deutsche Forschungs-gemeinschaft (DFG) in the framework of the priority programme “Antarctic Research with comparative investigations in Arctic ice areas” by grants LE1448/6-1 and LE1448/7-1. Julius Garbe acknowledges funding from the Leibniz Association (project DominoES)., Malte Meinshausen received funding from the National Science Foundation (NSF grant no. 1739031) through the PROPHET project, a component of the International Thwaites Glacier Collaboration (ITGC)., Christian Rodehacke has received funding from the European Research Council under the European Community’s Seventh Framework Programme (FP7/2007–2013)/ERC grant agreement 610055 as part of the Ice2Ice project., Financial support. This research has been supported by the U.S. Department of Energy (grant no. DE-AC02-05CH11231), the European Research Council (ICE2ICE (grant no. 610055)), the Dutch Ministry of Education, Culture and Science (grant no. 024.002.001), the Japan Society for the Promotion of Science (grant nos. JP16H02224, JP17H06104, and JP17H06323), the German Federal Ministry of Education and Research (BMBF) FONA (grant no. 01LP1511B), the German Research Foundation (grant nos. LE1448/6-1 and LE1448/7-1), and the National Science Foundation (grant no. 1852977)., A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. He-lene Seroussi and Nicole-Jeanne Schlegel were supported by grants from the NASA Cryospheric Science, Sea Level Change Team, and Modeling Analysis and Prediction programmes., Jonas Van Breedam and Philippe Huybrechts acknowledge support from the iceMOD project funded by the Research Foundation – Flanders (FWO-Vlaanderen)., Heiko Goelzer has received funding from the programme of the Netherlands Earth System Science Centre (NESSC), financially supported by the Dutch Ministry of Education, Culture and Science (OCW) under grant no. 024.002.001.
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; Antarctic; Southern Ocean; The Antarctic; Antarc*; Ice Sheet; Ice Shelf
• Online Access: https://hal.archives-ouvertes.fr/hal-03227889; https://hal.archives-ouvertes.fr/hal-03227889/document; https://hal.archives-ouvertes.fr/hal-03227889/file/esd-11-35-2020.pdf; https://doi.org/10.5194/esd-11-35-2020

International audience The sea level contribution of the Antarctic ice sheet constitutes a large uncertainty in future sea level projections. Here we apply a linear response theory approach to 16 state-of-the-art ice sheet models to estimate the Antarctic ice sheet contribution from basal ice shelf melting within the 21st century. The purpose of this computation is to estimate the uncertainty of Antarctica's future contribution to global sea level rise that arises from large uncertainty in the oceanic forcing and the associated ice shelf melting. Ice shelf melting is considered to be a major if not the largest perturbation of the ice sheet's flow into the ocean. However, by computing only the sea level contribution in response to ice shelf melting, our study is neglecting a number of processes such as surface-mass-balance-related contributions. In assuming linear response theory, we are able to capture complex temporal responses of the ice sheets, but we neglect any self-dampening or self-amplifying processes. This is particularly relevant in situations in which an instability is dominating the ice loss. The results obtained here are thus relevant, in particular wherever the ice loss is dominated by the forcing as opposed to an internal instability, for example in strong ocean warming scenarios. In order to allow for comparison the methodology was chosen to be exactly the same as in an earlier study (Levermann et al., 2014) but with 16 instead of 5 ice sheet models. We include uncertainty in the atmospheric warming response to carbon emissions (full range of CMIP5 climate model sensitivities), uncertainty in the oceanic transport to the Southern Ocean (obtained from the time-delayed and scaled oceanic subsurface warming in CMIP5 models in relation to the global mean surface warming), and the observed range of responses of basal ice shelf melting to oceanic warming outside the ice shelf cavity. This uncertainty in basal ice shelf melting is then convoluted with the linear response functions of each of the 16 ...