East Greenland ice core dust record reveals timing of Greenland ice sheet advance and retreat

Abstract Accurate estimates of the past extent of the Greenland ice sheet provide critical constraints for ice sheet models used to determine Greenland’s response to climate forcing and contribution to global sea level. Here we use a continuous ice core dust record from the Renland ice cap on the east coast of Greenland to constrain the timing of changes to the ice sheet margin and relative sea level over the last glacial cycle. During the Holocene and the previous interglacial period (Eemian) the dust record was dominated by coarse particles consistent with rock samples from central East Greenland. From the coarse particle concentration record we infer the East Greenland ice sheet margin advanced from 113.4 ± 0.4 to 111.0 ± 0.4 ka BP during the glacial onset and retreated from 12.1 ± 0.1 to 9.0 ± 0.1 ka BP during the last deglaciation. These findings constrain the possible response of the Greenland ice sheet to climate forcings.

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Greenland ice sheet contribution to sea level rise during the last interglacial period: a modelling study driven and constrained by ice core data

Climate of the Past ◽

10.5194/cp-9-353-2013 ◽

2013 ◽

Vol 9 (1) ◽

pp. 353-366 ◽

Cited By ~ 42

Author(s):

A. Quiquet ◽

C. Ritz ◽

H. J. Punge ◽

D. Salas y Mélia

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Ice Core ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Interglacial Period ◽

Last Interglacial ◽

Intergovernmental Panel ◽

Orbital Configuration ◽

Global Sea Level

Abstract. As pointed out by the forth assessment report of the Intergovernmental Panel on Climate Change, IPCC-AR4 (Meehl et al., 2007), the contribution of the two major ice sheets, Antarctica and Greenland, to global sea level rise, is a subject of key importance for the scientific community. By the end of the next century, a 3–5 °C warming is expected in Greenland. Similar temperatures in this region were reached during the last interglacial (LIG) period, 130–115 ka BP, due to a change in orbital configuration rather than to an anthropogenic forcing. Ice core evidence suggests that the Greenland ice sheet (GIS) survived this warm period, but great uncertainties remain about the total Greenland ice reduction during the LIG. Here we perform long-term simulations of the GIS using an improved ice sheet model. Both the methodologies chosen to reconstruct palaeoclimate and to calibrate the model are strongly based on proxy data. We suggest a relatively low contribution to LIG sea level rise from Greenland melting, ranging from 0.7 to 1.5 m of sea level equivalent, contrasting with previous studies. Our results suggest an important contribution of the Antarctic ice sheet to the LIG highstand.

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Coupled regional climate–ice-sheet simulation shows limited Greenland ice loss during the Eemian

Climate of the Past ◽

10.5194/cp-9-1773-2013 ◽

2013 ◽

Vol 9 (4) ◽

pp. 1773-1788 ◽

Cited By ~ 45

Author(s):

M. M. Helsen ◽

W. J. van de Berg ◽

R. S. W. van de Wal ◽

M. R. van den Broeke ◽

J. Oerlemans

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Regional Climate ◽

Ice Core ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Interglacial Period ◽

Temperature Record ◽

Last Interglacial ◽

Central Dome

Abstract. During the last interglacial period (Eemian, 130–115 kyr BP) eustatic global sea level likely peaked at > 6 m above the present-day level, but estimates of the contribution of the Greenland Ice Sheet vary widely. Here we use an asynchronously two-way-coupled regional climate–ice-sheet model, which includes physically realistic feedbacks between the changing ice sheet topography and climate forcing. Our simulation results in a contribution from the Greenland Ice Sheet to the Eemian sea level highstand between 1.2 and 3.5 m, with a most likely value of 2.1 m. Simulated Eemian ice loss in Greenland is dominated by the rapid retreat of the southwestern margin; two-thirds of the ice loss occurred south of 70° N. The southern dome survived the Eemian and remained connected to the central dome. Large-scale ice sheet retreat is prevented in areas with high accumulation. Our results broadly agree with ice-core-inferred elevation changes and marine records, but it does not match with the ice-core-derived temperature record from northern Greenland. During maximum Eemian summertime insolation, Greenland mass loss contributed ~ 0.5 m kyr−1 to sea level rise, 24% of the reconstructed total rate of sea level rise. Next to that, a difference of > 3 m remains between our maximum estimate of the Greenland contribution and the reconstructed minimum value of the global eustatic Eemian highstand. Hence, the Antarctic Ice Sheet must also have contributed significantly to this sea level highstand.

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Moderate Greenland ice sheet melt during the last interglacial constrained by present-day observations and paleo ice core reconstructions

10.5194/tc-2016-15 ◽

2016 ◽

Cited By ~ 4

Author(s):

P.M. Langebroek ◽

K.H. Nisancioglu

Keyword(s):

Sea Level ◽

Ice Core ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Ice Cores ◽

Atmospheric Temperature ◽

Lapse Rate ◽

Interglacial Period ◽

Last Interglacial ◽

Temperature Lapse Rate

Abstract. During the last interglacial period (LIG, ~ 130–115 ka before present, ka = 1000 yr) summer temperatures over Greenland were several degrees higher than today. It is likely that the Greenland ice sheet (GIS) was smaller than today, contributing to the reconstructed sea-level highstand of the LIG. However, the range of simulated GIS melt is large, and the location of the melt is uncertain. Here, we use temperature and precipitation patterns simulated by the Norwegian Earth System Model (NorESM) to investigate the volume, extent and stability of the GIS during the LIG. Present-day observations of ice sheet size, elevation and stability, together with paleo elevation information from five deep ice cores, are used to evaluate our ensemble of GIS simulations. Accepted simulations indicate a maximum GIS reduction equivalent to a global mean sea-level rise of 0.8–2.2 m compared to today, with most of the melt occurring in the southwest. The timing of the maximum ice melt over Greenland is simulated between 124 and 122 ka. We furthermore suggest a preferred mean value for the basal sliding parameter, relatively high PDD factors and an average to high atmospheric temperature lapse rate based on training the SICOPOLIS ice sheet model to observations and available LIG proxy data.

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How warm was Greenland during the last interglacial period?

Climate of the Past ◽

10.5194/cp-12-1933-2016 ◽

2016 ◽

Vol 12 (9) ◽

pp. 1933-1948 ◽

Cited By ~ 11

Author(s):

Amaelle Landais ◽

Valérie Masson-Delmotte ◽

Emilie Capron ◽

Petra M. Langebroek ◽

Pepijn Bakker ◽

...

Keyword(s):

Surface Temperature ◽

Ice Core ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Water Isotopes ◽

Interglacial Period ◽

Last Interglacial ◽

Last Interglacial Period ◽

Ice Sheet Topography ◽

North Greenland

Abstract. The last interglacial period (LIG, ∼ 129–116 thousand years ago) provides the most recent case study of multimillennial polar warming above the preindustrial level and a response of the Greenland and Antarctic ice sheets to this warming, as well as a test bed for climate and ice sheet models. Past changes in Greenland ice sheet thickness and surface temperature during this period were recently derived from the North Greenland Eemian Ice Drilling (NEEM) ice core records, northwest Greenland. The NEEM paradox has emerged from an estimated large local warming above the preindustrial level (7.5 ± 1.8 °C at the deposition site 126 kyr ago without correction for any overall ice sheet altitude changes between the LIG and the preindustrial period) based on water isotopes, together with limited local ice thinning, suggesting more resilience of the real Greenland ice sheet than shown in some ice sheet models. Here, we provide an independent assessment of the average LIG Greenland surface warming using ice core air isotopic composition (δ15N) and relationships between accumulation rate and temperature. The LIG surface temperature at the upstream NEEM deposition site without ice sheet altitude correction is estimated to be warmer by +8.5 ± 2.5 °C compared to the preindustrial period. This temperature estimate is consistent with the 7.5 ± 1.8 °C warming initially determined from NEEM water isotopes but at the upper end of the preindustrial period to LIG temperature difference of +5.2 ± 2.3 °C obtained at the NGRIP (North Greenland Ice Core Project) site by the same method. Climate simulations performed with present-day ice sheet topography lead in general to a warming smaller than reconstructed, but sensitivity tests show that larger amplitudes (up to 5 °C) are produced in response to prescribed changes in sea ice extent and ice sheet topography.

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Quantification of the Greenland ice sheet contribution to Last Interglacial sea level rise

Climate of the Past ◽

10.5194/cp-9-621-2013 ◽

2013 ◽

Vol 9 (2) ◽

pp. 621-639 ◽

Cited By ~ 71

Author(s):

E. J. Stone ◽

D. J. Lunt ◽

J. D. Annan ◽

J. C. Hargreaves

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Climate Model ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Ice Cores ◽

The Arctic ◽

Substantial Contribution ◽

Interglacial Period ◽

Last Interglacial

Abstract. During the Last Interglacial period (~ 130–115 thousand years ago) the Arctic climate was warmer than today, and global mean sea level was probably more than 6.6 m higher. However, there are large discrepancies in the estimated contributions to this sea level change from various sources (the Greenland and Antarctic ice sheets and smaller ice caps). Here, we determine probabilistically the likely contribution of Greenland ice sheet melt to Last Interglacial sea level rise, taking into account ice sheet model parametric uncertainty. We perform an ensemble of 500 Glimmer ice sheet model simulations forced with climatologies from the climate model HadCM3, and constrain the results with palaeodata from Greenland ice cores. Our results suggest a 90% probability that Greenland ice melt contributed at least 0.6 m, but less than 10% probability that it exceeded 3.5 m, a value which is lower than several recent estimates. Many of these previous estimates, however, did not include a full general circulation climate model that can capture atmospheric circulation and precipitation changes in response to changes in insolation forcing and orographic height. Our combined modelling and palaeodata approach suggests that the Greenland ice sheet is less sensitive to orbital forcing than previously thought, and it implicates Antarctic melt as providing a substantial contribution to Last Interglacial sea level rise. Future work should assess additional uncertainty due to inclusion of basal sliding and the direct effect of insolation on surface melt. In addition, the effect of uncertainty arising from climate model structural design should be taken into account by performing a multi-climate-model comparison.

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Reconciling reconstructions and simulations of the Greenland ice sheet and its climate during the Last Interglacial period

10.5194/egusphere-egu2020-19016 ◽

2020 ◽

Author(s):

Alexander Robinson ◽

Emilie Capron ◽

Jorge Alvarez-Solas ◽

Michael Bender ◽

Heiko Goelzer ◽

...

Keyword(s):

Climate Change ◽

Sea Level ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Ice Cores ◽

Future Climate Change ◽

Interglacial Period ◽

Last Interglacial ◽

Proxy Data ◽

Last Interglacial Period

<p>There is still no consensus concerning the evolution of the Greenland ice sheet during the Last Interglacial period (LIG, 130-115 kyr ago). Ice cores indicate that the ice sheet survived over most of the continent. Proxy data indicate temperature anomalies of up to 6-8&#176;C. However, under these conditions, models predict almost complete deglaciation. This paradox must be resolved to be able to quantify Greenland&#8217;s sea-level contribution during the LIG as well as to understand its sensitivity to future climate change. Here we analyze the available evidence and outline strategies to reconcile modeling and data efforts for Greenland during the LIG.</p>

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How warm was Greenland during the last interglacial period?

10.5194/cp-2016-28 ◽

2016 ◽

Cited By ~ 4

Author(s):

Amaelle Landais ◽

Valérie Masson-Delmotte ◽

Emilie Capron ◽

Petra M. Langebroek ◽

Pepijn Bakker ◽

...

Keyword(s):

Accumulation Rate ◽

Ice Core ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Water Isotopes ◽

Interglacial Period ◽

Last Interglacial ◽

Surface Warming ◽

Last Interglacial Period ◽

Industrial Level

Abstract. The last interglacial period (LIG, ~ 129–116 thousand years ago) provides the most recent case study for multi-millennial polar warming above pre-industrial level and a respective response of the Greenland and Antarctic ice sheets to this warming, as well as a test bed for climate and ice sheet models. Past changes in Greenland ice sheet thickness and surface temperature during this period were recently derived from the NEEM ice core records, North-West Greenland. The NEEM paradox has emerged from an estimated large local warming above pre-industrial level (7.5 ± 1.8 °C at the deposition site 126 ka ago without correction for any overall ice sheet altitude changes between the LIG and pre-industrial) based on water isotopes, together with limited local ice thinning, suggesting more resilience of the real Greenland ice sheet than shown in some ice sheet models. Here, we provide an independent assessment of the average LIG Greenland surface warming using ice core air isotopic composition (δ15N) and relationships between accumulation rate and temperature. The LIG surface temperature at the upstream NEEM deposition site without ice sheet altitude correction is estimated to be warmer by &plus;7 to &plus;11 °C (&plus;8 °C being the most likely estimate according to constraints on past accumulation rate) compared to the pre-industrial period. This temperature estimate is consistent with the 7.5 ± 1.8 °C warming initially determined from NEEM water isotopes. Moreover, we show that under such warm temperatures, melting of snow probably led to a significant firn shrinking by ~ 15 m. Climate simulations performed with present day ice sheet topography lead to much smaller warming but larger amplitudes (up to 5 °C) can be obtained from changes in sea ice extent and ice sheet topography. Still, ice sheet simulations forced by 5 °C surface warming lead to large ice sheet decay that are not compatible with existing data. Our new, independent temperature constrain therefore reinforces the NEEM paradox.

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Atmospheric gas records from Taylor Glacier, Antarctica, reveal ancient ice with ages spanning the entire last glacial cycle

Climate of the Past ◽

10.5194/cp-13-943-2017 ◽

2017 ◽

Vol 13 (7) ◽

pp. 943-958 ◽

Cited By ~ 10

Author(s):

Daniel Baggenstos ◽

Thomas K. Bauska ◽

Jeffrey P. Severinghaus ◽

James E. Lee ◽

Hinrich Schaefer ◽

...

Keyword(s):

Large Scale ◽

Ice Core ◽

Ice Sheet ◽

Last Deglaciation ◽

Glacial Cycle ◽

Last Glacial ◽

Climate Reconstructions ◽

Age Model ◽

Taylor Glacier ◽

The Last Glacial

Abstract. Old ice for paleo-environmental studies, traditionally accessed through deep core drilling on domes and ridges on the large ice sheets, can also be retrieved at the surface from ice sheet margins and blue ice areas. The practically unlimited amount of ice available at these sites satisfies a need in the community for studies of trace components requiring large sample volumes. For margin sites to be useful as ancient ice archives, the ice stratigraphy needs to be understood and age models need to be established. We present measurements of trapped gases in ice from Taylor Glacier, Antarctica, to date the ice and assess the completeness of the stratigraphic section. Using δ18O of O2 and methane concentrations, we unambiguously identify ice from the last glacial cycle, covering every climate interval from the early Holocene to the penultimate interglacial. A high-resolution transect reveals the last deglaciation and the Last Glacial Maximum (LGM) in detail. We observe large-scale deformation in the form of folding, but individual stratigraphic layers do not appear to have undergone irregular thinning. Rather, it appears that the entire LGM–deglaciation sequence has been transported from the interior of the ice sheet to the surface of Taylor Glacier relatively undisturbed. We present an age model that builds the foundation for gas studies on Taylor Glacier. A comparison with the Taylor Dome ice core confirms that the section we studied on Taylor Glacier is better suited for paleo-climate reconstructions of the LGM due to higher accumulation rates.

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Contribution of Greenland ice sheet melting to sea level rise during the last interglacial period: an approach combining ice sheet modelling and proxy data

Climate of the Past Discussions ◽

10.5194/cpd-8-3345-2012 ◽

2012 ◽

Vol 8 (4) ◽

pp. 3345-3377

Author(s):

A. Quiquet ◽

C. Ritz ◽

H. J. Punge ◽

D. Salas y Mélia

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Interglacial Period ◽

Last Interglacial ◽

Proxy Data ◽

Intergovernmental Panel ◽

Period Range ◽

Ice Sheet Modelling

Abstract. In the context of global warming, the contribution of the two major ice sheets, Antarctica and Greenland, to global sea level rise is a subject of key importance for the scientific community (4th assessment report of the Intergovernmental Panel on climate change, IPCC-AR4, Meehl et al., 2007). By the end of the next century, a 3–5 °C warm up is expected in Greenland. Similar temperatures in this region were reached during the last interglacial (LIG) period due to a change in orbital configuration rather than to anthropogenic forcing. Ice core evidence suggests that the Greenland Ice Sheet (GIS) has survived this warm period but great uncertainties remain about the total Greenland ice reduction during the LIG and its sea level rise contribution. In order to improve our confidence in future state projections, we first intend to reconstruct the past states of the GIS using ice sheet modelling, and confront the simulations with paleo data. The chosen methodoly of paleoclimate reconstruction is strongly based on proxy data. Proxy data are also used to constrain the ice sheet model during the calibration phase. Our estimates of Greenland melting contribution to sea level rise during the LIG period range from 0.65 to 1.5 m of sea level equivalent.

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Coupled regional climate–ice sheet simulation shows limited Greenland ice loss during the Eemian

Climate of the Past Discussions ◽

10.5194/cpd-9-1735-2013 ◽

2013 ◽

Vol 9 (2) ◽

pp. 1735-1770 ◽

Cited By ~ 4

Author(s):

M. M. Helsen ◽

W. J. van de Berg ◽

R. S. W. van de Wal ◽

M. R. van den Broeke ◽

J. Oerlemans

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Large Scale ◽

Regional Climate ◽

Ice Core ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Temperature Record ◽

Last Interglacial ◽

Central Dome

Abstract. During the last interglacial (Eemian, 130–115 kyr BP) eustatic global sea level likely peaked at >6 m above the present-day level, but estimates of the contribution of the Greenland ice sheet vary widely. Here we use an asynchronously two-way coupled regional climate–ice sheet model, which includes physically realistic feedbacks between the changing ice sheet topography and climate forcing. Our simulation results in a contribution from the Greenland ice sheet to the Eemian sea level highstand between 1.2 and 3.5 m, with a most likely value of 2.1 m. Simulated Eemian ice loss in Greenland is dominated by the rapid retreat of the southwestern margin: two-thirds of the ice loss occurred south of 70° N. The southern dome survived the Eemian and remained connected to the central dome. Large-scale ice sheet retreat is prevented in areas with high accumulation. Our results broadly agree with ice core inferred elevation changes and marine records, but it does not match with the ice-core derived temperature record from northern Greenland. During maximum Eemian summertime insolation, Greenland mass loss contributed ~0.5 m kyr−1 to sea level rise, 24% of the reconstructed total rate of sea level rise. Next to that, a difference of >3 m remains between our maximum estimate of the Greenland contribution and the reconstructed minimum value of the global eustatic Eemian highstand. Hence, the Antarctic ice sheet must also have contributed significantly to this sea level highstand.

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