Evironmental threats to marine mammals in the Canadian Arctic

Polar Record ◽  
1983 ◽  
Vol 21 (134) ◽  
pp. 433-449 ◽  
Author(s):  
Ian Stirling ◽  
Wendy Calvert
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Marine Mammals ◽  
Canadian Arctic ◽  
Ursus Maritimus ◽  
The Arctic ◽  
Polar Bears ◽  
Alopex Lagopus ◽  
Arctic Foxes ◽  
The Arctic Ocean

The Arctic Ocean is the home of three major groups of mammals that depend on the sea for survival and show varying degrees of adaptation for maritime life. Most fully adapted are the whales (Cetacea), which never leave the water, and the seals and walruses (Pinnipedia) that feed entirely at sea but emerge onto land or ice for pupping and basking. Less exclusively marine are two species of the order Carnivora—Polar Bears (Ursus maritimus), that seldom live far from the sea because they feed almost entirely upon seals, and Arctic Foxes (Alopex lagopus), some of which move out onto the sea ice during the winter, mainly to scavenge on the remains of seals killed by Polar Bears.

Recent changes in the exchange of sea ice between the Arctic Ocean and the Canadian Arctic Archipelago

2013 ◽  
Vol 118 (7) ◽  
pp. 3595-3607 ◽  
Author(s):  
Stephen E. L. Howell ◽  
Trudy Wohlleben ◽  
Mohammed Dabboor ◽  
Chris Derksen ◽  
Alexander Komarov ◽  
...  
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Canadian Arctic ◽  
The Arctic ◽  
Canadian Arctic Archipelago ◽  
The Arctic Ocean

scholarly journals Retention of ice-associated amphipods: possible consequences for an ice-free Arctic Ocean

2012 ◽  
Vol 8 (6) ◽  
pp. 1012-1015 ◽  
Author(s):  
J. Berge ◽  
Ø. Varpe ◽  
M. A. Moline ◽  
A. Wold ◽  
P. E. Renaud ◽  
...  
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Marine Mammals ◽  
Deep Ocean ◽  
Arctic Sea Ice ◽  
Ocean Currents ◽  
The Arctic ◽  
Arctic Sea ◽  
The Arctic Ocean ◽  
Deep Ocean Currents

Recent studies predict that the Arctic Ocean will have ice-free summers within the next 30 years. This poses a significant challenge for the marine organisms associated with the Arctic sea ice, such as marine mammals and, not least, the ice-associated crustaceans generally considered to spend their entire life on the underside of the Arctic sea ice. Based upon unique samples collected within the Arctic Ocean during the polar night, we provide a new conceptual understanding of an intimate connection between these under-ice crustaceans and the deep Arctic Ocean currents. We suggest that downwards vertical migrations, followed by polewards transport in deep ocean currents, are an adaptive trait of ice fauna that both increases survival during ice-free periods of the year and enables re-colonization of sea ice when they ascend within the Arctic Ocean. From an evolutionary perspective, this may have been an adaptation allowing success in a seasonally ice-covered Arctic. Our findings may ultimately change the perception of ice fauna as a biota imminently threatened by the predicted disappearance of perennial sea ice.

scholarly journals Regional variability of acidification in the Arctic: a sea of contrasts

2013 ◽  
Vol 10 (2) ◽  
pp. 2937-2965 ◽  
Author(s):  
E. E. Popova ◽  
A. Yool ◽  
A. C. Coward ◽  
T. R. Anderson
Keyword(s):  
Sea Ice ◽  
Primary Production ◽  
Arctic Ocean ◽  
Canadian Arctic ◽  
Atmospheric Co2 ◽  
The Arctic ◽  
Canadian Arctic Archipelago ◽  
Climate Feedbacks ◽  
Regional Variability ◽  
The Arctic Ocean

Abstract. The Arctic Ocean is a region that is particularly vulnerable to the impact of ocean acidification driven by rising atmospheric CO2, negatively impacting calcifying organisms such as coccolithophorids and foraminiferans. In this study, we use an ocean general circulation model, with embedded biogeochemistry and a full description of the carbon cycle, to study the response of pH and saturation states of calcite and aragonite to changing climate in the Arctic Ocean. Particular attention is paid to the strong regional variability within the Arctic and, for comparison, simulation results are contrasted with those for the global ocean. Simulations were run to year 2099 using the RCP 8.5 (the highest IPCC AR5 CO2 emission scenario). The separate impacts of the direct increase in atmospheric CO2 and indirect effects via climate feedbacks (changing temperature, stratification, primary production and fresh water fluxes) were examined by undertaking two simulations, one with the full system and the other in which ocean-atmosphera exchange of CO2 was prevented from increasing beyond the flux calculated for year 2000. Results indicate that climate feedbacks, and spatial heterogeneity thereof, play a strong role in the declines in pH and carbonate saturation (Ω) seen in the Arctic. The central Arctic, Canadian Arctic Archipelago and Baffin Bay show greatest rates of acidification and Ω decline as a result of melting sea ice. In contrast, areas affected by Atlantic inflow including the Greenland Sea and outer shelves of the Barents, Kara and Laptev seas, had minimal decreases in pH and Ω because weakening stratification associated with diminishing ice cover led to greater mixing and primary production. As a consequence, the predicted onset of undersaturation is highly variable regionally within the Arctic, occurring during the decade of 2000–2010 in the Siberian shelves and Canadian Arctic Archipelago, but as late as the 2080s in the Barents and Norwegian Seas. We conclude that, in order to make future projections of acidification and carbon saturation state in the Arctic, regional variability needs to be adequately resolved, with particular emphasis on reliable predictions of the rates of retreat of the sea-ice which are a major source of uncertainty.

Increased Arctic Ocean sea ice loss through the Canadian Arctic Archipelago under a warmer climate

2020 ◽  
Author(s):  
Stephen Howell ◽  
Mike Brady
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Canadian Arctic ◽  
Open Water ◽  
The Arctic ◽  
Canadian Arctic Archipelago ◽  
Nares Strait ◽  
The Arctic Ocean ◽  
Important Pathway

<p>The ice arches that ring the northern Canadian Arctic Archipelago have historically blocked the inflow of Arctic Ocean sea ice for the majority of the year. However, annual average air temperature in northern Canada has increased by more than 2°C over the past 65+ years and a warmer climate is expected to contribute to the deterioration of these ice arches, which in turn has implications for the overall loss of Arctic Ocean sea ice. We investigated the effect of warming on the Arctic Ocean ice area flux into the Canadian Arctic Archipelago using a 22-year record (1997-2018) of ice exchange derived from RADARSAT-1 and RADARSAT-2 imagery. Results indicated that there has been a significant increase in the amount of Arctic Ocean sea ice (10<sup>3</sup> km<sup>2</sup>/year) entering the northern Canadian Arctic Archipelago over the period of 1997-2018. The increased Arctic Ocean ice area flux was associated with reduced ice arch duration but also with faster (thinner) moving ice and more southern latitude open water leeway as a result of the Canadian Arctic Archipelago’s long-term transition to a younger and thinner ice regime. Remarkably, in 2016, the Arctic Ocean ice area flux into the Canadian Arctic Archipelago (161x10<sup>3</sup> km<sup>2</sup>) was 7 times greater than the 1997-2018 average (23x10<sup>3</sup> km<sup>2</sup>) and almost double the 2007 ice area flux into Nares Strait (87x10<sup>3</sup> km<sup>2</sup>). Indeed, Nares Strait is known to be an important pathway for Arctic Ocean ice loss however, the results of this study suggest that with continued warming, the Canadian Arctic Archipelago may also become a large contributor to Arctic Ocean ice loss.</p>

scholarly journals An Acoustic Ranging System to Measure Motion of Sea Ice

1977 ◽  
Vol 19 (81) ◽  
pp. 663-664
Author(s):  
R. H. Goodman ◽  
R. C. Clark
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Canadian Arctic ◽  
The Arctic ◽  
Commercial Activity ◽  
Acoustic Ranging ◽  
The Arctic Ocean ◽  
Design And Testing ◽  
Application Design

Abstract With the present increase of commercial activity in the Arctic Ocean, there is a growing need for advanced engineering techniques and instrumentation. This paper discusses the application, design and testing of an acoustic ranging system used to measure the motion of sea ice at potential ice-platform drilling locations in the Canadian Arctic.

scholarly journals An Acoustic Ranging System to Measure Motion of Sea Ice

1977 ◽  
Vol 19 (81) ◽  
pp. 663-664
Author(s):  
R. H. Goodman ◽  
R. C. Clark
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Canadian Arctic ◽  
The Arctic ◽  
Commercial Activity ◽  
Acoustic Ranging ◽  
The Arctic Ocean ◽  
Design And Testing ◽  
Application Design

AbstractWith the present increase of commercial activity in the Arctic Ocean, there is a growing need for advanced engineering techniques and instrumentation. This paper discusses the application, design and testing of an acoustic ranging system used to measure the motion of sea ice at potential ice-platform drilling locations in the Canadian Arctic.

The supply by air of Exercise “Musk-ox”, 1946

Polar Record ◽  
1952 ◽  
Vol 6 (43) ◽  
pp. 340-344
Author(s):  
R. H. Winfield
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
West Coast ◽  
Canadian Arctic ◽  
The Arctic ◽  
Hudson Bay ◽  
The West ◽  
Considerable Part ◽  
The Arctic Ocean ◽  
Musk Ox

It will be remembered that Exercise “Musk-Ox” began on 15 February 1946, when a mechanized force of forty-seven men in eleven Snowmobiles left Churchill on the west coast of Hudson Bay. This force travelled northwards to the Arctic Ocean, and then westwards over the sea ice to Cambridge Bay and Coppermine; from here the route lay southwards over the mainland to Fort Nelson and along the Alcan Highway to Grande Prairie, where the exercise ended in the first week of May. The route covered by the ground force is shown in the map on p. 341. The track of about 3000 miles is roughly the shape of a horseshoe extending from Churchill to Edmonton, with a considerable part of the curve lying within the Canadian Arctic.

scholarly journals Recent extreme light sea ice years in the Canadian Arctic Archipelago: 2011 and 2012 eclipse 1998 and 2007

2013 ◽  
Vol 7 (6) ◽  
pp. 1753-1768 ◽  
Author(s):  
S. E. L. Howell ◽  
T. Wohlleben ◽  
A. Komarov ◽  
L. Pizzolato ◽  
C. Derksen
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Atmospheric Circulation ◽  
Canadian Arctic ◽  
Surface Air Temperature ◽  
Ice Cover ◽  
The Arctic ◽  
Canadian Arctic Archipelago ◽  
Northwest Passage ◽  
The Arctic Ocean

Abstract. Remarkably low mean September sea ice area in the Canadian Arctic Archipelago (CAA) was observed in 2011 (146 × 103 km2), a record-breaking level that was nearly exceeded in 2012 (150 × 103 km2). These values were lower than previous September records set in 1998 (200 × 103 km2) and 2007 (220 × 103 km2), and are ∼60% lower than the 1981–2010 mean September climatology. In this study, the processes contributing to the extreme light years of 2011 and 2012 were investigated, compared to previous extreme minima of 1998 and 2007, and contrasted against historic summer seasons with above average September ice area. The 2011 minimum was associated with positive June through September (JJAS) surface air temperature (SAT) and net solar radiation (K*) anomalies that facilitated rapid melt, coupled with atmospheric circulation that restricted multi-year ice (MYI) inflow from the Arctic Ocean into the CAA. The 2012 minimum was also associated with positive JJAS SAT and K* anomalies with coincident rapid melt, but further ice decline was temporarily mitigated by atmospheric circulation which drove Arctic Ocean MYI inflow into the CAA. Atmospheric circulation was comparable between 2011 and 1998 (impeding Arctic Ocean MYI inflow) and 2012 and 2007 (inducing Arctic Ocean MYI inflow). However, preconditioning was more apparent leading up to 2011 and 2012 than 1998 and 2007. The rapid melt process in 2011 and 2012 was more intense than observed in 1998 and 2007 because of the thinner ice cover being more susceptible to anomalous thermodynamic forcing. The thinner sea ice cover within the CAA in recent years has also helped counteract the processes that facilitate extreme heavy ice years. The recent extreme light years within the CAA are associated with a longer navigation season within the Northwest Passage.

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