Twenty-first century ocean forcing of the Greenland ice sheet for modelling of sea level contribution
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...
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ftunivutrecht:oai:dspace.library.uu.nl:1874/395989 2023-11-12T04:17:27+01:00 Twenty-first century ocean forcing of the Greenland ice sheet for modelling of sea level contribution Slater, Donald A. Felikson, Denis Straneo, Fiamma Goelzer, Heiko Little, Christopher M. Morlighem, Mathieu Fettweis, Xavier Nowicki, Sophie Sub Dynamics Meteorology Marine and Atmospheric Research 2020-03-16 image/pdf https://dspace.library.uu.nl/handle/1874/395989 en eng 1994-0416 https://dspace.library.uu.nl/handle/1874/395989 info:eu-repo/semantics/OpenAccess Water Science and Technology Earth-Surface Processes Article 2020 ftunivutrecht 2023-11-01T23:23:18Z 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. Article in Journal/Newspaper glacier Greenland Ice Sheet Utrecht University Repository Greenland |
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Open Polar |
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Utrecht University Repository |
op_collection_id |
ftunivutrecht |
language |
English |
topic |
Water Science and Technology Earth-Surface Processes |
spellingShingle |
Water Science and Technology Earth-Surface Processes Slater, Donald A. Felikson, Denis Straneo, Fiamma Goelzer, Heiko Little, Christopher M. Morlighem, Mathieu Fettweis, Xavier Nowicki, Sophie Twenty-first century ocean forcing of the Greenland ice sheet for modelling of sea level contribution |
topic_facet |
Water Science and Technology Earth-Surface Processes |
description |
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. |
author2 |
Sub Dynamics Meteorology Marine and Atmospheric Research |
format |
Article in Journal/Newspaper |
author |
Slater, Donald A. Felikson, Denis Straneo, Fiamma Goelzer, Heiko Little, Christopher M. Morlighem, Mathieu Fettweis, Xavier Nowicki, Sophie |
author_facet |
Slater, Donald A. Felikson, Denis Straneo, Fiamma Goelzer, Heiko Little, Christopher M. Morlighem, Mathieu Fettweis, Xavier Nowicki, Sophie |
author_sort |
Slater, Donald A. |
title |
Twenty-first century ocean forcing of the Greenland ice sheet for modelling of sea level contribution |
title_short |
Twenty-first century ocean forcing of the Greenland ice sheet for modelling of sea level contribution |
title_full |
Twenty-first century ocean forcing of the Greenland ice sheet for modelling of sea level contribution |
title_fullStr |
Twenty-first century ocean forcing of the Greenland ice sheet for modelling of sea level contribution |
title_full_unstemmed |
Twenty-first century ocean forcing of the Greenland ice sheet for modelling of sea level contribution |
title_sort |
twenty-first century ocean forcing of the greenland ice sheet for modelling of sea level contribution |
publishDate |
2020 |
url |
https://dspace.library.uu.nl/handle/1874/395989 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
glacier Greenland Ice Sheet |
genre_facet |
glacier Greenland Ice Sheet |
op_relation |
1994-0416 https://dspace.library.uu.nl/handle/1874/395989 |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1782334338967273472 |