Coeval fluctuations of the Greenland ice sheet and a local glacier, central East Greenland, during late glacial and early Holocene time

• Published in: Geophysical research letters Vol. 43; no. 4; pp. 1623 - 1631
• Main Authors: Levy, Laura B., Kelly, Meredith A., Lowell, Thomas V., Hall, Brenda L., Howley, Jennifer A., Smith, Colby A.
• Format: Journal Article
• Language: English
• Published: Washington John Wiley & Sons, Inc 28-02-2016
• Subjects: 10Be dating; Ablation; Age; Annual temperatures; Bedrock; Beryllium 10; Boulders; Chronology; Climate; Climatic conditions; Fluctuation; Fluctuations; Glaciation; Glaciers; Greenland; Greenland ice sheet; Holocene; Ice; Ice caps; Ice cores; Ice sheets; Land; Land ice; late glacial; Mean annual temperatures; Moraines; Outlets; Preboreal; Records; Sea level; Seasonal variations; Seasonality; Summer; Summer temperatures; Time; Younger Dryas; PN, Greenland, Greenland Ice Sheet; ANE, Greenland, Oestgroenland; AN, Greenland
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1002/2015GL067108

We present a 10Be chronology of late glacial to early Holocene fluctuations of a Greenland ice sheet outlet glacier and the adjacent Milne Land ice cap in central East Greenland. Ages of boulders on bedrock indicate that both ice masses receded during the Younger Dryas (YD), likely due to rising summer temperatures. Since Greenland ice core records register cold mean annual temperatures throughout the YD, these ice‐marginal data support climate conditions characterized by strong seasonality. The ice sheet outlet glacier and ice cap deposited inner Milne Land Stade moraines at 11.4 ± 0.8 ka and 11.4 ± 0.6 ka, respectively (mean moraine ages and 1σ uncertainties). Based on the coeval moraine ages, we suggest that both ice masses responded to climate conditions acting on the ice margins, specifically ablation. Moreover, the ice sheet responded sensitively (i.e., on the same time scale as a small ice cap) to climate conditions.
Key Points
Beryllium‐10 ages show deglaciation during the Younger Dryas in central East Greenland
The inner Milne Land Stade moraines of the Greenland ice sheet and a local glacier date to ~11.4 ka
Both ice masses responded in unison to late glacial and early Holocene climate conditions