A comparison of late glacial-early Holocene fluctuations of Greenland Ice Sheet outlet glaciers with nearby mountain glaciers in central east Greenland

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Højmark Thomsen, H., Reeh, N., Olesen, O. B., Egede Bøggilde, C., Starzer, W., Weidick, A., & Higgins, A. K. (1997). The Nioghalvfjerdsfjorden glacier project, North-East Greenland: a study of ice sheet response to climatic change. Geology of Greenland Survey Bulletin, 176, 95-103. https://doi.org/10.34194/ggub.v176.5073 _______________ Glaciological research was initiated in 1996 on the floating glacier tongue filling Nioghalvfjerdsfjorden in NorthEast Greenland (Fig. 1), with the aim of acquiring a better understanding of the response of the Greenland ice sheet (Inland Ice) to changing climate, and the implications for future sea level. The research is part of a three year project (1996–98) to advance research into the basic processes that contribute to changes in the ocean volume with a changing climate. Five nations are participants in the project, which is supported by the European Community (EC) Environment and Climate Programme. The Geological Survey of Denmark and Greenland (GEUS) and the Danish Polar Center are the Danish partners in the project, both with integrated research themes concentrated on and around Nioghalvfjerdsfjorden.

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The Holocene thermal maximum in the Nordic Seas: the impact of Greenland Ice Sheet melt and other forcings in a coupled atmosphere–sea-ice–ocean model

Climate of the Past ◽

10.5194/cp-9-1629-2013 ◽

2013 ◽

Vol 9 (4) ◽

pp. 1629-1643 ◽

Cited By ~ 23

Author(s):

M. Blaschek ◽

H. Renssen

Keyword(s):

Ice Sheet ◽

Greenland Ice Sheet ◽

Early Holocene ◽

Surface Cooling ◽

Holocene Climate ◽

Nordic Seas ◽

The Holocene ◽

Holocene Thermal Maximum ◽

Thermal Maximum ◽

The Impact

Abstract. The relatively warm early Holocene climate in the Nordic Seas, known as the Holocene thermal maximum (HTM), is often associated with an orbitally forced summer insolation maximum at 10 ka BP. The spatial and temporal response recorded in proxy data in the North Atlantic and the Nordic Seas reveals a complex interaction of mechanisms active in the HTM. Previous studies have investigated the impact of the Laurentide Ice Sheet (LIS), as a remnant from the previous glacial period, altering climate conditions with a continuous supply of melt water to the Labrador Sea and adjacent seas and with a downwind cooling effect from the remnant LIS. In our present work we extend this approach by investigating the impact of the Greenland Ice Sheet (GIS) on the early Holocene climate and the HTM. Reconstructions suggest melt rates of 13 mSv for 9 ka BP, which result in our model in an ocean surface cooling of up to 2 K near Greenland. Reconstructed summer SST gradients agree best with our simulation including GIS melt, confirming that the impact of the early Holocene GIS is crucial for understanding the HTM characteristics in the Nordic Seas area. This implies that modern and near-future GIS melt can be expected to play an active role in the climate system in the centuries to come.

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Oceanic heat delivery via Kangerdlugssuaq Fjord to the south-east Greenland ice sheet

Journal of Geophysical Research Oceans ◽

10.1002/2013jc009295 ◽

2014 ◽

Vol 119 (2) ◽

pp. 631-645 ◽

Cited By ~ 53

Author(s):

Mark E. Inall ◽

Tavi Murray ◽

Finlo R. Cottier ◽

Kilian Scharrer ◽

Timothy J. Boyd ◽

...

Keyword(s):

Ice Sheet ◽

Greenland Ice Sheet ◽

The South ◽

East Greenland

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Basal Drainage System Response to Increasing Surface Melt on the Greenland Ice Sheet

Science ◽

10.1126/science.1235905 ◽

2013 ◽

Vol 341 (6147) ◽

pp. 777-779 ◽

Cited By ~ 102

Author(s):

T. Meierbachtol ◽

J. Harper ◽

N. Humphrey

Keyword(s):

Conceptual Models ◽

Ice Sheet ◽

Drainage System ◽

Greenland Ice Sheet ◽

System Response ◽

Mountain Glaciers ◽

In Situ Observations ◽

Key Aspects ◽

Conduit Development

Surface meltwater reaching the bed of the Greenland ice sheet imparts a fundamental control on basal motion. Sliding speed depends on ice/bed coupling, dictated by the configuration and pressure of the hydrologic drainage system. In situ observations in a four-site transect containing 23 boreholes drilled to Greenland’s bed reveal basal water pressures unfavorable to water-draining conduit development extending inland beneath deep ice. This finding is supported by numerical analysis based on realistic ice sheet geometry. Slow meltback of ice walls limits conduit growth, inhibiting their capacity to transport increased discharge. Key aspects of current conceptual models for Greenland basal hydrology, derived primarily from the study of mountain glaciers, appear to be limited to a portion of the ablation zone near the ice sheet margin.

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Response of the southern Greenland Ice Sheet to early Holocene and Last Interglacial Climate

Quaternary International ◽

10.1016/j.quaint.2012.07.352 ◽

2012 ◽

Vol 279-280 ◽

pp. 80

Author(s):

Anders Carlson

Keyword(s):

Ice Sheet ◽

Greenland Ice Sheet ◽

Early Holocene ◽

Last Interglacial

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The Holocene thermal maximum in the Nordic Seas: the impact of Greenland Ice Sheet melt and other forcings in a coupled atmosphere-sea ice-ocean model

Climate of the Past Discussions ◽

10.5194/cpd-8-5263-2012 ◽

2012 ◽

Vol 8 (5) ◽

pp. 5263-5291 ◽

Cited By ~ 2

Author(s):

M. Blaschek ◽

H. Renssen

Keyword(s):

Ice Sheet ◽

Greenland Ice Sheet ◽

Early Holocene ◽

Surface Cooling ◽

Holocene Climate ◽

Nordic Seas ◽

The Holocene ◽

Holocene Thermal Maximum ◽

Thermal Maximum ◽

The Impact

Abstract. The relatively warm early Holocene climate in the Nordic Seas, known as the Holocene Thermal Maximum (HTM), is often associated with an orbitally forced summer insolation maximum at 10 ka BP. The spatial and temporal response recorded in proxy data in the North Atlantic and the Nordic Seas reveal a complex interaction of mechanisms active in the HTM. Previous studies have investigated the impact of the Laurentide Ice Sheet (LIS), as a remnant from a previous glacial period, altering climate conditions with a continuous supply of melt water to the Labrador Sea and adjacent seas and with a downwind cooling effect from the remnant LIS. In our present work we extend this approach by investigating the impact of the Greenland Ice Sheet (GIS) on the early Holocene climate and the HTM. Reconstructions suggest melt rates of 13 mSv for 9 ka BP, which result in our model in a ocean surface cooling of up to 2 K near Greenland. Reconstructed summer SST gradients agree best with our simulation including GIS melt, confirming that the impact of early Holocene GIS is crucial for understanding the HTM characteristics in the Nordic Seas area. This implies that the modern and near-future GIS melt can be expected to play an active role in the climate system in the centuries to come.

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Maximum Southwest Greenland Ice Sheet Recession in the Early Holocene

Geophysical Research Letters ◽

10.1029/2019gl083164 ◽

2020 ◽

Vol 47 (1) ◽

Cited By ~ 6

Author(s):

A. J. Lesnek ◽

J. P. Briner ◽

N. E. Young ◽

J. K. Cuzzone

Keyword(s):

Ice Sheet ◽

Greenland Ice Sheet ◽

Early Holocene ◽

Southwest Greenland

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

Nature Communications ◽

10.1038/s41467-019-12546-2 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 10

Author(s):

Marius Folden Simonsen ◽

Giovanni Baccolo ◽

Thomas Blunier ◽

Alejandra Borunda ◽

Barbara Delmonte ◽

...

Keyword(s):

Sea Level ◽

Ice Core ◽

Ice Sheet ◽

Greenland Ice Sheet ◽

Interglacial Period ◽

Last Deglaciation ◽

Glacial Cycle ◽

East Greenland ◽

Ice Cap ◽

Climate Forcings

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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The meltwater feedbacks on ice dynamics, influence of melt amplitude, duration and extent.

10.5194/egusphere-egu21-1099 ◽

2021 ◽

Author(s):

Basile de Fleurian ◽

Petra M. Langebroeke ◽

Richard Davy

Keyword(s):

Water Pressure ◽

Ice Sheet ◽

Drainage System ◽

Greenland Ice Sheet ◽

System Model ◽

Ice Dynamics ◽

Mountain Glaciers ◽

Different Characteristics ◽

Crucial Parameter ◽

Subglacial Drainage

In recent years, temperatures over the Greenland ice sheet have been rising, leading to an increase in surface melt. This increase however can not be reduced to a simple number. Throughout the recent years we have seen some extreme melt seasons with melt extending over the whole surface of the ice sheet (2012) or melt seasons of lower amplitudes but with a longer duration (2010). The effect of those variations on the subglacial system and hence on ice dynamic are poorly understood and are still mainly deduced from studies based on mountain glaciers.Here we apply the Ice-sheet and Sea-level System Model (ISSM) to a synthetic glacier with a geometry similar to a Greenland ice sheet land terminating glacier. The forcing is designed such that it allows to investigate different characteristics of the melt season: its length, intensity or the spatial extension of the melt. Subglacial hydrology and ice dynamics are coupled within ISSM is coupled to a subglacial hydrology model, allowing to study the response of the system in terms of subglacial water pressure and the final impact on ice dynamics. Of particular interest is the evolution of the distribution of the efficient and inefficient component of the subglacial drainage system which directly impacts the water pressure evolution at the base of the glacier.We note that the initiation of the melt season and the intensity of the melt at this period is a crucial parameter when studying the dynamic response of the glacier to different melt season characteristics. From those results, we can infer a more precise evolution of the dynamics of land terminating glaciers that are heavily driven by their subglacial drainage system. We also highlight which changes in the melt season pattern would be the most damageable for glacier stability in the future.

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