Late glacial and Holocene glaciation history of North and Northeast Greenland

• Published in: Arctic, Antarctic, and Alpine Research
• Main Authors: Nicolaj K. Larsen, Anne Sofie Søndergaard, Laura B. Levy, Astrid Strunk, Daniel S. Skov, Anders Bjørk, Shfaqat A. Khan, Jesper Olsen
• Format: Article in Journal/Newspaper
• Language: English
• Published: Taylor & Francis Group 2022
• Subjects: Greenland Ice Sheet; cosmogenic exposure dating; deglaciation; Environmental sciences; GE1-350; Ecology; QH540-549.5; Greenland; Antarctic and Alpine Research; Arctic; Ice Sheet
• Online Access: https://doi.org/10.1080/15230430.2022.2094607; https://doaj.org/article/19377fa6f40e4ac4899406324b4bc205

Northeast Greenland is the place where the Greenland Ice Sheet (GrIS) experienced the largest areal changes since the Last Glacial Maximum. However, the age constraints of the last deglaciation are in some areas sparse. In this study, we use forty-seven new 10Be cosmogenic exposure ages to constrain the deglaciation of the present-day ice-free areas in Northeast Greenland. Our results show that the outer coast region was deglaciated between 12.8 ± 0.6 and 11.5 ± 0.2 ka and the region close to the present ice margin was deglaciated 2 to 4 ka later between 9.2 ± 0.3 to 8.6 ± 0.3 ka. By combining our new results with previously published data from North and Northeast Greenland, we find that the ice sheet advanced to the shelf edge between 26 and 20 cal. ka BP. The outer coast was deglaciated between 12.8 and 9.7 ka and the present ice extent was reached between 10.8 to 5.8 ka. The ice margin continued to retreat farther inland during the Middle Holocene before it readvanced toward its Little Ice Age position. The deglaciation was probably forced by a combination of increased atmospheric and ocean temperatures, but local topography also played an important role. These results add to the growing knowledge about the glaciation history of the GrIS and add useful constraints for future ice sheet models.