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Title: Thick and old sea ice in the Beaufort Sea during summer 2020/21 was associated with enhanced transport
Abstract The Arctic Ocean has seen a remarkable reduction in sea ice coverage, thickness and age since the 1980s. These changes are most pronounced in the Beaufort Sea, with a transition around 2007 from a regime dominated by multi-year sea ice to one with large expanses of open water during the summer. Using satellite-based observations of sea ice, an atmospheric reanalysis and a coupled ice-ocean model, we show that during the summers of 2020 and 2021, the Beaufort Sea hosted anomalously large concentrations of thick and old ice. We show that ice advection contributed to these anomalies, with 2020 dominated by eastward transport from the Chukchi Sea, and 2021 dominated by transport from the Last Ice Area to the north of Canada and Greenland. Since 2007, cool season (fall, winter, and spring) ice volume transport into the Beaufort Sea accounts for ~45% of the variability in early summer ice volume—a threefold increase from that associated with conditions prior to 2007. This variability is likely to impact marine infrastructure and ecosystems.  more » « less
Award ID(s):
1751363 1744587
NSF-PAR ID:
10403817
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Communications Earth & Environment
Volume:
3
Issue:
1
ISSN:
2662-4435
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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