An Examination of the Non-Formation of the North Water Polynya Ice Arch

The North Water (NOW), situated between Ellesmere Island and Greenland in northern Baffin Bay, is the largest recurring polynya in the Canadian Arctic. Historically, the northern border of the NOW is defined by an ice arch that forms annually in Kane Basin, which is part of the Nares Strait system. In 2007 the NOW ice arch failed to consolidate for the first time since observations began in the 1950s. The non-formation of the NOW ice arch occurred again in 2009, 2010, 2017 and 2019. Satellite Advanced Very High Resolution Radiometry data shows that large floes broke off from the normally stable landfast ice in Kane Basin for each of these years, impeding ice arch formation. A closer analysis of a 2019 event, in which 2500 km2 of ice sheared away from Kane Basin, indicates that significant tidal forces played a role. The evidence suggests that thinning ice from a warming climate combined with large amplitude tides is a key factor in the changing ice dynamics of the NOW region. The non-formation of the NOW ice arch results in an increased loss of multiyear ice through Nares Strait.

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A Study of the North Water Polynya Ice Arch using Four Decades of Satellite Data

Scientific Reports ◽

10.1038/s41598-019-56780-6 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 5

Author(s):

R. F. Vincent

Keyword(s):

Linear Trend ◽

Arctic Basin ◽

The Arctic ◽

Heat Of Fusion ◽

Nares Strait ◽

The North ◽

North Water Polynya ◽

Northern Border ◽

North Water ◽

Polar Ocean

AbstractPolynyas are sections of the polar ocean that remain relatively ice-free during winter, imparting significant physical and biological impact on the region. The North Water polynya (NOW) situated between Ellesmere Island and Greenland is the largest recurring Arctic polynya. Historically, the NOW forms every season when Arctic Ocean floes moving southward through Nares Strait become congested and form an ice arch that defines the northern border of the polynya. This blockage usually forms during winter and breaks down in spring. It is conjectured that the polynya is maintained by latent heat of fusion from the continuous formation of new ice as floes are swept southward from the ice arch by wind and ocean currents. Analysis of four decades of satellite imagery indicates a growing instability in the location of the ice arch, challenging previous models of polynya maintenance. A linear trend of the data indicates the number of days of Nares Strait blockage has decreased 2.1 days/year between 1979 and 2019 with wide interannual variations. Prior to 2007, ice arches blocked Nares Strait an average of 177 days/year compared to 128 days/year since that time. The overall trend of reduced ice arch duration is a contributing factor to the dramatic loss of multiyear ice in the Arctic basin.

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Abundance of Atlantic walrus in Western Nares Strait, Baffin Bay Stock, during summer

NAMMCO Scientific Publications ◽

10.7557/3.2611 ◽

2014 ◽

Vol 9 ◽

pp. 123 ◽

Cited By ~ 5

Author(s):

Robert EA Stewart ◽

Erik W Born ◽

Rune Dietz ◽

Mads Peter Heide-Jørgensen ◽

Frank Farsø Rigét ◽

...

Keyword(s):

Water Surface ◽

Open Water ◽

Ellesmere Island ◽

Baffin Bay ◽

Nares Strait ◽

The North ◽

North Water Polynya ◽

Odobenus Rosmarus ◽

North Water ◽

Odobenus Rosmarus Rosmarus

Atlantic walruses (Odobenus rosmarus rosmarus) belonging to the Baffin Bay subpopulation occur year round in the North Water polynya (NOW) between NW Greenland and eastern Ellesmere Island (Canada). They are hunted for subsistence purposes by residents of the Qaanaaq area (NW Greenland) bordering the NOW to the east and by Canadian Inuit at the entrance to Jones Sound in Nunavut. During the open-water period NW Greenland is virtually devoid of walruses which concentrate along eastern and southern Ellesmere Island at this time of the year. To determine the abundance of walruses in the NOW area, aerial surveys were conducted in August of 1999, 2008, and 2009. In July 2009, nine satellite-linked transmitters were deployed in nearby Kane Basin. Surveys on 9 and 20 August 2009 along eastern Ellesmere Island were the most extensive and were augmented with concomitant data on haul-out and at water surface activity from three (1 F, 2 M) of the nine tags that were still functioning. We therefore focus on the 2009 surveys. Walruses were observed on the ice and in water primarily in Buchanan Bay and Princess Marie Bay where the remaining functional tags were located. The Minimum Counted population (MCP) was 571 on 20 August. Adjusting the MCP of walruses on ice for those not hauled out, the estimate of abundance of walruses in the Baffin Bay stock was 1,251(CV=1.00, 95% CI = 1,226) when adjusted by the proportion of tags ‘dry’ at the time of the survey and 1,249 (CV=1.12, 95% CI = 1,370) when adjusted by the average time tags were dry. The surveys did not cover all potential walrus summering habitat along eastern Ellesmere Island and are negatively biased to an unknown degree.

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A case-study in tracking 1998 polynya ice dynamics in Smith Sound, North Water polynya region, Canadian Arctic, using RADARSAT-1 data

Annals of Glaciology ◽

10.3189/172756401781818815 ◽

2001 ◽

Vol 33 ◽

pp. 413-418 ◽

Cited By ~ 2

Author(s):

K. J. Wilson ◽

D. J. King ◽

D. G. Barber

Keyword(s):

Canadian Arctic ◽

Ice Dynamics ◽

The North ◽

North Water Polynya ◽

North Water ◽

Oceanic Forcing ◽

The Mean ◽

Insight Into

AbstractMonitoring ice motion provides insight into the relative contributions of atmospheric and oceanic forcing to polynya dynamics In this study ice kinematics in the North Water (NOW) region, northern Baffin Bay Canadian Arctic are determined using time-sequential RADARSAT-1 ScanSARWide imagery (from the period January-December 1998), processed by the automated ice-tracking algorithm (Tracker) currently used at the Canadian Ice Service (CIS). A case-study is then carried out on the Smith Sound region from January till the end of june 1998 to monitor polynya formation, maintenance and disintegration. This has two objectives: (1) to evaluate satellite ice-motion products as a means of better understanding the relative contributions of latent- and sensible-heat mechanisms responsible for the formation and behaviour of the NOW polynya, and (2) to study the influence of winds on regional sea-ice motion. Derived ice-motion maps were validated using in situ ice beacons deployed onto floes in the NOW region during the 1998 ship-based science experiment. Tracker-derived displacement and directional regressions were 0.93 and 0.79, respectively, with a total standard error of 3.6 km in magnitude and 38.8° in direction. Analysis of monthly mean ice-motion maps shows that a significant export of ice occurs from the polynya. A comparison of weekly-averaged ice motion with the mean wind-field data suggests that ice export in Smith Sound is influenced by synoptic-scale atmospheric pressure systems.

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Modeling the Dynamics of the North Water Polynya Ice Bridge

Journal of Physical Oceanography ◽

10.1175/2008jpo3965.1 ◽

2009 ◽

Vol 39 (6) ◽

pp. 1448-1461 ◽

Cited By ~ 39

Author(s):

Dany Dumont ◽

Yves Gratton ◽

Todd E. Arbetter

Keyword(s):

Climate Modeling ◽

Global Climate ◽

Narrow Channel ◽

Long Term Stability ◽

Global Climate Modeling ◽

Nares Strait ◽

The North ◽

North Water Polynya ◽

Optimal Value ◽

North Water

Abstract The North Water polynya, the largest polynya in the world, forms annually and recurrently in Smith Sound in northern Baffin Bay. Its formation is governed in part by the formation of an ice bridge in the narrow channel of Nares Strait below Kane Basin. Here, the widely used elastic–viscous–plastic elliptical rheology dynamic sea ice model is applied to the region. The idealized case is tested over a range of values for e = [1.2, 2.0] and initial ice thicknesses from 0.75 to 3.5 m, using constant northerly winds over a period of 30 days, to evaluate long-term stability of different rheological parameterizations. Idealized high-resolution simulations show that the formation of a stable ice bridge is possible for e ≤ 1.8. The dependence of the solution in terms of grid discretization is studied with a domain rotated 45°. A realistic domain with realistic forcing is also tested to compare time-variant solutions to actual observations. Cohesion has a remarkable impact on if and when the ice bridge will form and fail, assessing its importance for regional and global climate modeling, but the lack of observational thickness data during polynya events prevents the authors from identifying an optimal value for e.

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Living at a High Arctic Polynya: Inughuit Settlement and Subsistence around the North Water during the Thule Station Period, 1910–53

ARCTIC ◽

10.14430/arctic4573 ◽

2016 ◽

Vol 69 (5) ◽

pp. 1 ◽

Cited By ~ 6

Author(s):

Bjarne Grønnow

Keyword(s):

Raw Materials ◽

High Arctic ◽

Ringed Seal ◽

Site Location ◽

Ice Cap ◽

The North ◽

North Water Polynya ◽

Annual Range ◽

North Water ◽

The Rich

The settlement and subsistence patterns of the Inughuit of the Avanersuaq (Thule area) are described and analyzed for the years 1910 to 1953, when Knud Rasmussen’s trading station at Dundas was active. Inughuit subsistence was based on the rich biotic resources of the North Water polynya between Ellesmere Island and Greenland, but the analysis shows that trade, primarily with fox furs at the Thule Station, also played a major role in shaping the settlement pattern of the period. During the Thule Station Period, the named winter settlements amounted to c. 40 sites; however, only 10–15 of them were settled at any given time. The Inughuit settlement close to the station, Uummannaq, soon became the largest site in the area. The sources enable us to follow changes of residence of some hunting families over four decades. By moving their winter sites every second or third year, the families gained primary knowledge of the topography and seasonal variation of the hunting grounds in the entire Thule district during their active years. In the same way, they connected with diverse family networks through the years. Tracing the sledge routes that connected the sites over great distances reveals how decisive proximity to main and escape routes over the Ice Cap was for site location. Dog sledge technology, and thus capacity to transport people, gear, and stored food, boomed during the Thule Station Period with the wealth created from trade and access to raw materials. Mapping the main hunting grounds on the sea ice and modeling the hunters’ annual range of possibilities for accessing different game—mainly walrus, ringed seal, narwhal, and sea birds (plus some caribou)—showed that ringed seal formed the bread and butter of the subsistence economy. However, bulk resources, gained in particular from intensive spring walrus hunts at a few hot spots, as well as carefully timed consumption and sharing of the stored meat and blubber, were keys to life at the North Water polynya. Temporary settlement at the trading stations in the area—a couple of winters at a time—was also part of the risk management strategy of the Inughuit.

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