A reassessment of the role of ice sheet glaciation in the long-term evolution of the East Greenland fjord region
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The contrasting behaviour of the two ice sheets is probably linked to the palaeoceanographic circulation pattern in the Polar North Atlantic. East Greenland is under the influence of the cold East Greenland Current, whereas the development and behaviour of ice in the Barents Sea is influenced by the continuous, but highly variable. North Atlantic meridional current system that has resulted in a northward inflow of relatively warm waters of Atlantic origin on the eastern side of the Polar North Atlantic. Of particular interest are the so-called “Nordway events” in glacial stages 6 and 4 to 2. These represented periods of pronounced inflow of temperate waters from the south and an associated increase in seasonally open waters, providing moisture for ice-sheet growth. The largest of these events ended in major glaciations, which were reflected in terrestrial glacial sequences and in deep-sea records of ice-rafted debris.

Differences in ice extent and dynamics around the Polar North Atlantic are expressed in the evolution and architecture of its east and west continental margins. The Svalbard-Barents Sea Ice Sheet developed much later than the East Greenland Ice Sheet, in the Late Pliocene as compared with the Middle/Late Miocene. The Svalbard-Barents Sea margin is characterised by major prograding fans, built mainly of stacked debris flows. These fans are interpreted as products of rapid sediment delivery from fast-flowing ice streams reaching the shelf break during full glacial conditions. Such major submarine fans are not found north of the Scoresby Sund Fan off East Greenland, where ice seldom reached the shelf break, sedimentation rates were relatively low and sediment transport appears to have been localised in several major deep-sea submarine channel systems. Few debris flows are present and more uniform, acoustically-stratified sediments predominate. In general, the Greenland Ice Sheet has been more stable than those on the European North Atlantic margin, which reflect greater variability in heat and moisture transfer at timescale varying from 100,000 year glacial cycles to millennial-scale fluctuations.


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Oxygen and carbon isotope composition of Quaternary biv...
Palaeogeography, Palaeoclimatology, Palaeoecology
Oxygen and carbon isotope composition of Quaternary bivalve shells as a water mass indicator: Last interglacial and Holocene, East Greenland
Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 111, Issues 1-2, September 1994, Pages 119-124
Carsten Israelson, Bjørn Buchardt, Svend Funder, Hans W. Hubberten

Abstract
Oxygen and carbon isotope composition of arctic bivalve shells are used in an attempt to reconstruct surface water temperature and salinities in Scoresby Sund, East Greenland. The oxygen isotope compositions of Mya truncata, Hiatella arctica and Tridonta borealis have been compared with present day hydrological parameters. Modern shells yield oxygen isotope values that, on the whole, reproduce the environmental temperature and sea water isotopic composition. Furthermore, it is possible to estimate the living depth of the analysed specimens. Analyses of growth increments from single shells show that there are large variations from year to year in temperature and oxygen isotope composition of the surface waters of Scoresby Sund and that these variations decrease with depth. Analyses of Holocene shells indicate that the Polar Current water, which flows from north to south along the East Greenland coast was also present during the Holocene climatic optimum 8000-7000 yr B.P. Analyses of bivalve shells from the last interglacial show that Scoresby Sund during that time was well circulated and that meltwater from the Greenland ice sheet and sea ice meltwater was important for the temperature, salinity and isotopic composition of the surface waters.

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Constraints on the Greenland Ice Sheet since the Last G...
Quaternary Science Reviews
Constraints on the Greenland Ice Sheet since the Last Glacial Maximum from sea-level observations and glacial-rebound models
Quaternary Science Reviews, Volume 23, Issues 9-10, May 2004, Pages 1053-1077
Kevin Fleming, Kurt Lambeck

Abstract
Geomorphological descriptions of changes in the extent of the Greenland Ice Sheet (GIS) have been combined with glacial-isostatic-adjustment models to reproduce the sea-level history of Greenland since the Last Glacial Maximum (LGM). The contribution to past sea-level change around Greenland due to ice-load changes outside of that region has been considerable (± 10's of meters), while still contributing a rise of several mm yr−1 today. The isostatic contribution to relative sea level around Greenland from changes in the GIS is found by iteratively perturbing preliminary ice models with different LGM extents and deglaciation starting times. The resulting first-order model that provides the best agreement between observed and predicted sea level contributes 3.1 and 1.9 m water-equivalent of additional ice relative to present-day ice volumes at the LGM and Younger Dryas, respectively. The GIS in most areas does not appear to have extended far onto the continental shelf, the exceptions being southern-most Southwest Greenland and northern East Greenland, as well as at the coalescence of the Northwest Greenland and Innuitian Ice Sheets. Changes in ice thickness since the LGM were >500 m along the present-day outer coast and >1500 m along some parts of the present-day ice margin. The observed mid- to late-Holocene fall in sea level to below the present-day level and the subsequent transgression seen in some areas implies that the GIS retreated behind the present-day margin by distances of the order of 40 km before readvancing.

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doi:10.1016/j.geomorph.2007.02.048
Copyright © 2007 Elsevier B.V. All rights reserved.

A reassessment of the role of ice sheet glaciation in the long-term evolution of the East Greenland fjord region

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