Quantifying flow regimes in a Greenland glacial fjord using iceberg drifters

• Published in: Geophysical Research Letters
• Main Authors: Sutherland, David A., Roth, George E., Hamilton, Gordon S., Mernild, Sebastian H., Stearns, Leigh A., Straneo, Fiammetta
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Geophysical Union (AGU) 2016
• Subjects: Icebergs; Fjord circulation; Ice melange; East Greenland Current; Greenland ice sheet; Iceberg melt; Greenland; East Greenland; east greenland current; glacier; Ice Sheet; Sea ice; Sermilik
• Online Access: http://hdl.handle.net/1808/22253; https://doi.org/10.1002/2014GL062256

Large, deep-keeled icebergs are ubiquitous in Greenland's outlet glacial fjords. Here we use the movement of these icebergs to quantify flow variability in Sermilik Fjord, southeast Greenland, from the ice mélange through the fjord to the shelf. In the ice mélange, a proglacial mixture of sea ice and icebergs, we find that icebergs consistently track the glacier speed, with slightly faster speeds near terminus and episodic increases due to calving events. In the fjord, icebergs accurately capture synoptic circulation driven by both along-fjord and along-shelf winds. Recirculation and in-/out-fjord variations occur throughout the fjord more frequently than previously reported, suggesting that across-fjord velocity gradients cannot be ignored. Once on the shelf, icebergs move southeastward in the East Greenland Coastal Current, providing wintertime observations of this freshwater pathway. Funded by The National Science Foundation. Grant Numbers: OCE-1130008, ARC-0909274 and The University of Oregon.