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Title: Sea Ice Dynamics in Hudson Strait and Its Impact on Winter Shipping Operations
Abstract

Hudson Strait is seasonally ice covered and is the only part of the Canadian Arctic where winter shipping takes place. Yet, very little is known about the thickness and dynamics of this ice pack. During winter operations, icebreakers often face besetting events, which can slow or immobilize vessels for up to a few days. Using in situ observations of ice draft and drift collected by moored sonars at two sites in Hudson Strait from 2005 to 2009, we provide the first detailed analysis of sea ice dynamics within Hudson Strait and provide insights into the processes that dictate ice thickness and internal pressure along this unique winter shipping corridor. Prevailing northwesterly winds drive south‐southeastward ice motion within the Strait, maintaining polynyas along Baffin Island on the north side of the Strait, and compressing the ice pack against Nunavik on the southern side. As a result, ice on the northern side remains young and thin throughout winter ( = 1.25 m), whereas ice on the southern side is older, heavily deformed and ∼60% thicker by March ( = 2.01 m). Intermittent reversals to southeasterly winds decompress the ice pack on the southern side, increasing the presence of leads and easing navigation through the ice pack to the port in Deception Bay. The spatial variability in sea ice thickness elucidated by the moorings is corroborated at the regional scale using satellite observations from ICESat‐2 during winter 2019, 2020, and 2021, and complimented by high‐resolution fields of sea ice motion during winter 2021.

 
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Award ID(s):
1948482
NSF-PAR ID:
10362557
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Journal of Geophysical Research: Oceans
Volume:
126
Issue:
12
ISSN:
2169-9275
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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