Supplementary material to "The future sea-level contribution of the Greenland ice sheet: a multi-model ensemble study of ISMIP6"

AbstractThe dynamic/thermodynamic shallow-ice model SICOPOLIS is applied to the Greenland ice sheet. Paleoclimatic spin-ups from 125 ka BP until today, as well as future-climate experiments 500 years into the future, are carried out with three different grid spacings, namely 20, 10 and 5 km. The scenarios are a subset of those specified by the SeaRISE (Sea-level Response to Ice Sheet Evolution) community effort. The bed topography includes improved troughs for Jakobshavn Isbræ, Helheim, Kangerdlugssuaq and Petermann glaciers, processed by an algorithm that preserves shape, orientation and continuity of the troughs on the 5 km scale. Comparison of simulated and observed present-day surface velocities shows that these ice streams and outlet glaciers are resolved with different accuracies, ranging from poor (20 km grid) to reasonably good (5 km grid). In the future-climate experiments, the simulated absolute ice volumes depend significantly on the resolution, while the sensitivities (ice volumes relative to the constant-climate control run) vary only by a few centimeters of sea-level equivalent.

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Supplementary material to "Remapping of Greenland ice sheet surface mass balance anomalies for large ensemble sea-level change projections"

10.5194/tc-2019-188-supplement ◽

2019 ◽

Author(s):

Heiko Goelzer ◽

Brice P. Y. Noel ◽

Tamsin L. Edwards ◽

Xavier Fettweis ◽

Jonathan M. Gregory ◽

...

Keyword(s):

Mass Balance ◽

Sea Level ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Sea Level Change ◽

Surface Mass Balance ◽

Surface Mass ◽

Sheet Surface ◽

Level Change ◽

Supplementary Material

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Simulations of the Greenland ice sheet 100 years into the future with the full Stokes model Elmer/Ice

Journal of Glaciology ◽

10.3189/2012jog11j177 ◽

2012 ◽

Vol 58 (209) ◽

pp. 427-440 ◽

Cited By ~ 91

Author(s):

Hakime Seddik ◽

Ralf Greve ◽

Thomas Zwinger ◽

Fabien Gillet-Chaulet ◽

Olivier Gagliardini

Keyword(s):

Global Warming ◽

Sea Level Rise ◽

Sea Level ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Ice Streams ◽

Simulation Code ◽

Dynamic Scenario ◽

The Future ◽

Basal Sliding

AbstractIt is likely that climate change will have a significant impact on the mass balance of the Greenland ice sheet, contributing to future sea-level rise. Here we present the implementation of the full Stokes model Elmer/Ice for the Greenland ice sheet, which includes a mesh refinement technique in order to resolve fast-flowing ice streams and outlet glaciers. We discuss simulations 100 years into the future, forced by scenarios defined by the SeaRISE (Sea-level Response to Ice Sheet Evolution) community effort. For comparison, the same experiments are also run with the shallow-ice model SICOPOLIS (SImulation COde for POLythermal Ice Sheets). We find that Elmer/Ice is ~43% more sensitive (exhibits a larger loss of ice-sheet volume relative to the control run) than SICOPOLIS for the ice-dynamic scenario (doubled basal sliding), but ~61 % less sensitive for the direct global warming scenario (based on the A1 B moderate-emission scenario for greenhouse gases). The scenario with combined A1B global warming and doubled basal sliding forcing produces a Greenland contribution to sea-level rise of ~15cm for Elmer/Ice and ~12cm for SICOPOLIS over the next 100 years.

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The GRISLI-LSCE contribution to the Ice Sheet Model Intercomparison Project for phase 6 of the Coupled Model Intercomparison Project (ISMIP6) – Part 1: Projections of the Greenland ice sheet evolution by the end of the 21st century

The Cryosphere ◽

10.5194/tc-15-1015-2021 ◽

2021 ◽

Vol 15 (2) ◽

pp. 1015-1030 ◽

Cited By ~ 1

Author(s):

Aurélien Quiquet ◽

Christophe Dumas

Keyword(s):

Mass Loss ◽

Sea Level Rise ◽

Sea Level ◽

Ice Sheet ◽

Coupled Model ◽

Greenland Ice Sheet ◽

Model Intercomparison ◽

The Future ◽

Intercomparison Project ◽

Global Sea Level

Abstract. Polar amplification will result in amplified temperature changes in the Arctic with respect to the rest of the globe, making the Greenland ice sheet particularly vulnerable to global warming. While the ice sheet has been showing an increased mass loss in the past decades, its contribution to global sea level rise in the future is of primary importance since it is at present the largest single-source contribution after the thermosteric contribution. The question of the fate of the Greenland and Antarctic ice sheets for the next century has recently gathered various ice sheet models in a common framework within the Ice Sheet Model Intercomparison Project for the Coupled Model Intercomparison Project – phase 6 (ISMIP6). While in a companion paper we present the GRISLI-LSCE (Grenoble Ice Sheet and Land Ice model of the Laboratoire des Sciences du Climat et de l'Environnement) contribution to ISMIP6-Antarctica, we present here the GRISLI-LSCE contribution to ISMIP6-Greenland. We show an important spread in the simulated Greenland ice loss in the future depending on the climate forcing used. The contribution of the ice sheet to global sea level rise in 2100 can thus be from as low as 20 mm sea level equivalent (SLE) to as high as 160 mm SLE. Amongst the models tested in ISMIP6, the Coupled Model Intercomparison Project – phase 6 (CMIP6) models produce larger ice sheet retreat than their CMIP5 counterparts. Low-emission scenarios in the future drastically reduce the ice mass loss. The oceanic forcing contributes to about 10 mm SLE in 2100 in our simulations. In addition, the dynamical contribution to ice thickness change is small compared to the impact of surface mass balance. This suggests that mass loss is mostly driven by atmospheric warming and associated ablation at the ice sheet margin. With additional sensitivity experiments we also show that the spread in mass loss is only weakly affected by the choice of the ice sheet model mechanical parameters.

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A regional atmospheric warming threshold for irreversible Greenland ice sheet mass loss

10.5194/egusphere-egu2020-19032 ◽

2020 ◽

Author(s):

Michiel van den Broeke ◽

Brice Noël ◽

Leo van Kampenhout ◽

Willem-Jan van de Berg

Keyword(s):

Mass Loss ◽

Mass Balance ◽

Sea Level Rise ◽

Sea Level ◽

Climate Models ◽

Climate Model ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Global Climate Models ◽

The Future

<p>The mass balance of the Greenland ice sheet (GrIS, units Gt per year) equals the surface mass balance (SMB) minus solid ice discharge across the grounding line. As the latter is definite positive, an important threshold for irreversible GrIS mass loss occurs when long-term average SMB becomes negative. For this to happen, runoff (mainly meltwater, some rain) must exceed mass accumulation (mainly snowfall minus sublimation). Even for a single year, this threshold has not been passed since at least 1958, the first year with reliable estimates of SMB components, although recent years with warm summers (e.g. 2012 and 2019) came close. Simply extrapolating the recent (1991-present) negative SMB trend into the future suggests that the SMB = 0 threshold could be reached before ~2040, but such predictions are extremely uncertain given the very large interannual SMB variability, the relative brevity of the time series and the uncertainty in future warming. In this study we use a cascade of models, extensively evaluated with in-situ and remotely sensed (GRACE) SMB observations, to better constrain the future regional warming threshold for the 5-year average GrIS SMB to become negative. To this end, a 1950-2100 climate change run with the global model CESM2 (app. 100 km resolution) was dynamically downscaled using the regional climate model RACMO2 (app. 11 km), which in turn was statistically downscaled to 1 km resolution. The result is a threshold regional Greenland warming of close to 4 degrees. We then use a range of CMIP5 and CMIP6 global climate models to translate the regional value into a global warming threshold for various warming scenarios, including its timing this century. We find substantial differences, ranging from stabilization before the threshold is reached in the RCP/SSP2.6 scenarios with a limited but still significant sea-level rise contribution (< 5 cm by 2100) to an imminent crossing of the warming threshold for the RCP/SSP8.5 scenarios with substantial and ever-growing contributions to sea level rise (> 10 cm by 2100). These results stress the need for strong mitigation to avoid irreversible GrIS mass loss. We finish by discussing the caveats and uncertainties of our approach.</p>

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Supplementary material to "21st century ocean forcing of the Greenland Ice Sheet for modeling of sea level contribution"

10.5194/tc-2019-222-supplement ◽

2019 ◽

Author(s):

Donald A. Slater ◽

Denis Felikson ◽

Fiamma Straneo ◽

Heiko Goelzer ◽

Christopher M. Little ◽

...

Keyword(s):

Sea Level ◽

21St Century ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Supplementary Material

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The GRISLI-LSCE contribution to ISMIP6, Part 1: projections of the Greenland ice sheet evolution by the end of the 21<sup>st</sup> century

10.5194/tc-2020-139 ◽

2020 ◽

Author(s):

Aurélien Quiquet ◽

Christophe Dumas

Keyword(s):

Mass Loss ◽

Sea Level Rise ◽

Sea Level ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Companion Paper ◽

The Arctic ◽

The Future ◽

Common Framework ◽

Global Sea Level

Abstract. Polar amplification will result in amplified temperature changes in the Arctic with respect to the rest of the globe making the Greenland ice sheet particularly vulnerable to global warming. While the ice sheet has been showing an increase mass loss in the past decades, its contribution to global sea level rise in the future is of primary importance since it is at present the largest single source contribution behind the thermosteric contribution. The question of the fate of the Greenland and Antarctic ice sheets for the next century has recently gathered various ice sheet models in a common framework within the Ice Sheet Model Intercomparison Project for CMIP6. While in a companion paper we present the GRISLI-LSCE contribution to ISMIP6-Antarctica, we present here the GRISLI-LSCE contribution to ISMIP6-Greenland. We show an important spread in the simulated Greenland ice loss in the future depending on the climate forcing used. The contribution of the ice sheet to global sea level rise in 2100 can be thus as low as 20 mmSLE to as high as 160 mmSLE. The CMIP6 models produce much larger ice sheet retreat than their CMIP5 counterparts. Low emission scenarios in the future drastically reduce the ice mass loss. The mass loss is mostly driven by atmospheric warming and associated ablation at the ice sheet margin while oceanic forcing contributes to about 10 mmSLE in 2100 in our simulations.

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Meltwater refreezing in the accumulation area of the Greenland ice sheet: Pâkitsoq, summer 1991

Rapport Grønlands Geologiske Undersøgelse ◽

10.34194/rapggu.v155.8172 ◽

1992 ◽

Vol 155 ◽

pp. 13-17

Author(s):

R.J Braithwaite ◽

W.T Pfeffer ◽

H Blatter ◽

N.F Humphrey

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Temperature Rise ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Public Concern ◽

The Future

There is public concern that warmer climate in the future may cause extra melting of glaciers, including the Greenland ice sheet, with a resulting rise in World sea level (Warrick & Oerlemans, 1990). Recent estimates of sea level rise from Greenland include 0.36–0.48 mm/year per °C temperature rise (Braithwaite & Olesen, 1990) but much work is still needed to make reliable forecasts.

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