Article révisé par les pairs
Résumé : Abstract. Changes in ocean temperature and salinity are expected to be an important determinant of the Greenland ice sheet's future sea level contribution. Yet, simulating the impact of these changes in continental-scale ice sheet models remains challenging due to the small scale of key physics, such as fjord circulation and plume dynamics, and poor understanding of critical processes, such as calving and submarine melting. Here we present the ocean forcing strategy for Greenland ice sheet models taking part in the Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6), the primary community effort to provide 21st century sea level projections for the Intergovernmental Panel on Climate Change Sixth Assessment Report. Beginning from global atmosphere–ocean general circulation models, we describe two complementary approaches to provide ocean boundary conditions for Greenland ice sheet models, termed the “retreat” and “submarine melt” implementations. The retreat implementation parameterises glacier retreat as a function of projected subglacial discharge and ocean thermal forcing, is designed to be implementable by all ice sheet models and results in retreat of around 1 and 15 km by 2100 in RCP2.6 and 8.5 scenarios, respectively. The submarine melt implementation provides estimated submarine melting only, leaving the ice sheet model to solve for the resulting calving and glacier retreat and suggests submarine melt rates will change little under RCP2.6 but will approximately triple by 2100 under RCP8.5. Both implementations have necessarily made use of simplifying assumptions and poorly constrained parameterisations and, as such, further research on submarine melting, calving and fjord–shelf exchange should remain a priority. Nevertheless, the presented framework will allow an ensemble of Greenland ice sheet models to be systematically and consistently forced by the ocean for the first time and should result in a significant improvement in projections of the Greenland ice sheet's contribution to future sea level change.

Documents en relation

DI-fusion

  • On calculating the sea-level contribution in marine ice-sheet models
    par Goelzer, Heiko , Coulon, Violaine
    Publication 2023-09-13
  • PROTECT perspectives on ice-sheet modelling
    par Pattyn, Frank , Coulon, Violaine , Goelzer, Heiko
    Publication 2023-10-11
  • Short- and long-term variability of the Antarctic and Greenland ice sheets
    par Hanna, Edward , Topál, Dániel , Box, Jason J.E. , Buzzard, Sammie , Christie, Frazer , Hvidberg, Christine , Morlighem, Mathieu , De Santis, Laura , Silvano, Alessandro , Colleoni, Florence , Sasgen, Ingo , Banwell, Alison F. , van den Broeke, Michiel R. , DeConto, Robert , De Rydt, Jan , Goelzer, Heiko , Gossart, Alexandra , Gudmundsson, G. Hilmar , Lindbäck, Katrin , Miles, Bertie B.W.J. , Mottram, Ruth , Pattyn, Frank , Reese, Ronja , Rignot, Eric , Srivastava, Aakriti , Sun, Sainan , Toller, Justin , Tuckett, Peter , Ultee, Lizz
    Publication 2024-02
  • Insights into the vulnerability of Antarctic glaciers from the ISMIP6 ice sheet model ensemble and associated uncertainty
    par Seroussi, Helene , Verjans, Vincent , Nowicki, Sophie , Payne, Antony J. , Goelzer, Heiko , Lipscomb, William H. , Abe-Ouchi, Ayako , Agosta, Cecile , Albrecht, Torsten , Asay-Davis, Xylar , Barthel, Alice , Calov, Reinhard , Cullather, Richard , Dumas, Christophe , Galton-Fenzi, Benjamin K. , Gladstone, Rupert R.M. , Golledge, Nicholas R. , Gregory, Jonathan M. , Greve, Ralf , Hattermann, Tore , Hoffman, Matthew J. , Humbert, Angelika , Huybrechts, Philippe , Jourdain, Nicolas C. , Kleiner, Thomas , Larour, Eric , Leguy, Gunter R. , Lowry, Daniel P. , Little, Chistopher M. , Morlighem, Mathieu , Pattyn, Frank , Pelle, Tyler , Price, Stephen F. , Quiquet, Aurelien , Reese, Ronja , Schlegel, Nicole-Jeanne , Shepherd, Andrew , Simon, Erika , Smith, Robin R.S. , Straneo, Fiammetta , Sun, Sainan , Trusel, Luke D. , Van Breedam, Jonas , Van Katwyk, Peter , van de Wal, Roderik S W , Winkelmann, Ricarda , Zhao, Chen , Zhang, Tong , Zwinger, Thomas
    Publication 2023-12-01
  • Four years of active sampling of atmospheric polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAHs in Dronning Maud Land, East Antarctica
    par Van Overmeiren, Preben , De Wispelaere, Patrick , Demeestere, Kristof , Gili, Stefania , Mangold, Alexander , De Causmaecker, Karen , Mattielli, Nadine , Delcloo, Andy , Van Langenhove, H , Walgraeve, Christophe
    Publication 2024-02-10