BIOLOGICAL AND OCEANOGRAPHIC CONDITIONS IN HUDSON BAY 6. BRYOZOA FROM HUDSON BAY AND STRAIT

1932 ◽  
Vol 7 (1) ◽  
pp. 361-376 ◽  
Author(s):  
RAYMOND C. OSBURN
Keyword(s):  
Arctic Ocean ◽  
The Other ◽  
The Arctic ◽  
Hudson Bay ◽  
Arctic Circle ◽  
Northeastern Part ◽  
Davis Strait ◽  
The Arctic Ocean ◽  
Oceanographic Conditions ◽  
Made In

The Hudson bay, a great inland sea situated well to the south of the arctic circle, has its two entrances at the northern extremity, one into the Arctic ocean and the other through Hudson strait into Davis strait. As the whole region lies within the area of the most recent glaciation, its fauna must have been re-established since the recession of the glacier from northern sources. This will probably explain the fact that practically all of the species are those of Greenland and arctic America, which in turn are chiefly circumpolar in distribution.Collections made in 1897, 1904, 1927, 1928, 1929 and 1930 of bryozoan material from the northeastern part of the bay, from Hudson strait, and from the region about Port Churchill in Manitoba, show seventy-five species and well marked varieties, including two species described as new, Bugula simpliciformis and Callopora ungavensis, with one striking variety, Gemellaria loricata var. cornuta.

scholarly journals How relevant is the deposition of mercury onto snowpacks? – Part 2: A modeling study

2012 ◽  
Vol 12 (1) ◽  
pp. 2647-2706 ◽  
Author(s):  
D. Durnford ◽  
A. Dastoor ◽  
A. Ryzhkov ◽  
L. Poissant ◽  
M. Pilote ◽  
...  
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Atmospheric Mercury ◽  
The Arctic ◽  
Hudson Bay ◽  
Arctic Circle ◽  
Surface Level ◽  
The Arctic Ocean ◽  
Simulated Concentration ◽  
The Impact

Abstract. An unknown fraction of mercury that is deposited onto snowpacks is revolatilized to the atmosphere. Determining the revolatilized fraction is important since mercury that enters the snowpack meltwater may be converted to highly toxic bioaccumulating methylmercury. In this study, we present a new dynamic physically-based snowpack/meltwater model for mercury that is suitable for large-scale atmospheric models for mercury. It represents the primary physical and chemical processes that determine the fate of mercury deposited onto snowpacks. The snowpack/meltwater model was implemented in Environment Canada's atmospheric mercury model GRAHM. For the first time, observed snowpack-related mercury concentrations are used to evaluate and constrain an atmospheric mercury model. We find that simulated concentrations of mercury in both snowpacks and the atmosphere's surface layer agree closely with observations. The simulated concentration of mercury in both in the top 30 cm and the top 150 cm of the snowpack, averaged over 2005–2009, is predominantly below 6 ng l−1 over land south of 66.5° N but exceeds 18 ng l−1 over sea ice in extensive areas of the Arctic Ocean and Hudson Bay. The average simulated concentration of mercury in snowpack meltwater runoff tends to be higher on the Russian/European side (>20 ng l−1) of the Arctic Ocean than on the Canadian side (<10 ng l−1). The correlation coefficient between observed and simulated monthly mean atmospheric surface-level GEM concentrations increased significantly with the inclusion of the new snowpack/meltwater model at two of the three stations (midlatitude, subarctic) studied and remained constant at the third (arctic). Oceanic emissions are postulated to produce the observed summertime maximum in concentrations of surface-level atmospheric GEM at Alert in the Canadian Arctic and to generate the summertime volatility observed in these concentrations at both Alert and Kuujjuarapik on subarctic Hudson Bay, Canada. We find that the fraction of deposited mercury that is revolatilized from snowpacks increases with latitude from 28% between 30 and 45° N, to 51% from 45 to 66.5° N, to 70% polewards of 66.5° N on an annual basis. Combining this latitudinal gradient with the latitudinally increasing coverage of snowpacks causes yearly net deposition as a fraction of gross deposition to decrease from 98% between 30 and 45° N to 85% between 45 and 66.5° N to 44% within the Arctic Circle. The yearly net deposition and net accumulation of mercury at the surface within the Arctic Circle north of 66.5° N are estimated at 153 and 117 Mg, respectively. We calculate that 63 and 45 Mg of mercury are deposited annually to the Arctic Ocean directly and indirectly via melting snowpacks, respectively. For terrestrial surfaces within the Arctic Circle, we find that 24 and 21 Mg of mercury are deposited annually directly and indirectly via melting snowpacks, respectively. Within the Arctic Circle, multi-season snowpacks gained an estimated average of 136 kg of mercury annually on land but lost an average of 133 kg annually over sea ice, possibly as a result of increased melting caused by rising temperatures. The developed snowpack/meltwater model can be used for investigating the impact of climate change on the snowpack/atmosphere exchange of mercury.

scholarly journals How relevant is the deposition of mercury onto snowpacks? – Part 2: A modeling study

2012 ◽  
Vol 12 (19) ◽  
pp. 9251-9274 ◽  
Author(s):  
D. Durnford ◽  
A. Dastoor ◽  
A. Ryzhkov ◽  
L. Poissant ◽  
M. Pilote ◽  
...  
Keyword(s):  
Sea Ice ◽  
Arctic Ocean ◽  
Atmospheric Mercury ◽  
The Arctic ◽  
Hudson Bay ◽  
Arctic Circle ◽  
Surface Level ◽  
The Arctic Ocean ◽  
Simulated Concentration ◽  
The Impact

Abstract. An unknown fraction of mercury that is deposited onto snowpacks is revolatilized to the atmosphere. Determining the revolatilized fraction is important since mercury that enters the snowpack meltwater may be converted to highly toxic bioaccumulating methylmercury. In this study, we present a new dynamic physically-based snowpack/meltwater model for mercury that is suitable for large-scale atmospheric models for mercury. It represents the primary physical and chemical processes that determine the fate of mercury deposited onto snowpacks. The snowpack/meltwater model was implemented in Environment Canada's atmospheric mercury model GRAHM. For the first time, observed snowpack-related mercury concentrations are used to evaluate and constrain an atmospheric mercury model. We find that simulated concentrations of mercury in both snowpacks and the atmosphere's surface layer agree closely with observations. The simulated concentration of mercury in both in the top 30 cm and the top 150 cm of the snowpack, averaged over 2005–2009, is predominantly below 6 ng L−1 over land south of 66.5° N but exceeds 18 ng L−1 over sea ice in extensive areas of the Arctic Ocean and Hudson Bay. The average simulated concentration of mercury in snowpack meltwater runoff tends to be higher on the Russian/European side (>20 ng L−1) of the Arctic Ocean than on the Canadian side (<10 ng L−1). The correlation coefficient between observed and simulated monthly mean atmospheric surface-level gaseous elemental mercury (GEM) concentrations increased significantly with the inclusion of the new snowpack/meltwater model at two of the three stations (midlatitude, subarctic) studied and remained constant at the third (arctic). Oceanic emissions are postulated to produce the observed summertime maximum in concentrations of surface-level atmospheric GEM at Alert in the Canadian Arctic and to generate the summertime volatility observed in these concentrations at both Alert and Kuujjuarapik on subarctic Hudson Bay, Canada. We find that the fraction of deposited mercury that is revolatilized from snowpacks increases with latitude from 39% between 30 and 45° N, to 57% from 45 to 60° N, 67% from 60 to 66.5° N, and 75% polewards of 66.5° N on an annual basis. Combining this latitudinal gradient with the latitudinally increasing coverage of snowpacks causes yearly net deposition as a fraction of gross deposition to decrease from 98% between 30 and 45° N to 89% between 45 and 60° N, 73% between 60 and 66.5° N, and 44% within the Arctic Circle. The yearly net deposition and net accumulation of mercury at the surface within the Arctic Circle north of 66.5° N are estimated at 153 and 117 Mg, respectively. We calculate that 58 and 50 Mg of mercury are deposited annually to the Arctic Ocean directly and indirectly via melting snowpacks, respectively. For terrestrial surfaces within the Arctic Circle, we find that 29 and 16 Mg of mercury are deposited annually directly and indirectly via melting snowpacks, respectively. Within the Arctic Circle, multi-season snowpacks on land and over sea ice gained, on average, an estimated 0.1 and 0.4 Mg yr−1 mercury, respectively, from 2000–2005. The developed snowpack/meltwater model can be used for investigating the impact of climate change on the snowpack/atmosphere exchange of mercury.

scholarly journals Desecuritization as Displacement of Controversy: geopolitics, law and sovereign rights in the Arctic

Politik ◽  
2017 ◽  
Vol 20 (3) ◽  
Author(s):  
Marc Jacobsen ◽  
Jeppe Strandsbjerg
Keyword(s):  
Arctic Ocean ◽  
International Law ◽  
Indigenous Peoples ◽  
North Pole ◽  
The Other ◽  
The Arctic ◽  
The Arctic Ocean ◽  
Securitization Theory ◽  
The Media ◽  
The One

By signing the Ilulissat Declaration of May 2008, the five littoral states of the Arctic Ocean pre-emptively desecuritized potential geopolitical controversies in the Arctic Ocean by confirming that international law and geo-science are the defining factors underlying the future delimitation. This happened in response to a rising securitization discourse fueled by commentators and the media in the wake of the 2007 Russian flag planting on the geographical North Pole seabed, which also triggered harder interstate rhetoric and dramatic headlines. This case, however, challenges some established conventions within securitization theory. It was state elites that initiated desecuritization and they did so by shifting issues in danger of being securitized from security to other techniques of government. Contrary to the democratic ethos of the theory, these shifts do not necessarily represent more democratic procedures. Instead, each of these techniques are populated by their own experts and technocrats operating according to logics of right (law) and accuracy (science). While shifting techniques of government might diminish the danger of securitized relations between states, the shift generates a displacement of controversy. Within international law we have seen controversy over its ontological foundations and within science we have seen controversy over standards of science. Each of these are amplified and take a particularly political significance when an issue is securitized via relocation to another technique. While the Ilulissat Declaration has been successful in minimizing the horizontal conflict potential between states it has simultaneously given way for vertical disputes between the signatory states on the one hand and the Indigenous peoples of the Arctic on the other.

Atmospheric, oceanic, and sea-ice variability along Nares Strait: a numerical model study

2021 ◽  
Author(s):  
Yarisbel Garcia Quintana ◽  
Paul G. Myers ◽  
Kent Moore
Keyword(s):  
Numerical Model ◽  
Sea Ice ◽  
Arctic Ocean ◽  
North Atlantic ◽  
The Other ◽  
The Arctic ◽  
Nares Strait ◽  
The North ◽  
The Arctic Ocean ◽  
The North Atlantic

&lt;p&gt;Nares Strait, between Greenland and Ellesmere Island, is one of the main pathways connecting the Arctic Ocean to the North Atlantic. The multi-year sea ice that is transported through the strait plays an important role in the mass balance of Arctic sea-ice as well as influencing the climate of the North Atlantic region. This transport is modulated by the formation of ice arches that form at the southern and northern of the strait.&amp;#160; The arches also play an important role in the maintenance of the North Water Polynya (NOW) that forms at the southern end of the strait. The NOW is one of the largest and most productive of Arctic polynyas.&amp;#160;Given its significance, we use an eddy-permitting regional configuration of the Nucleus for European Modelling of the Ocean (NEMO) to explore sea-ice variability along Nares Strait, from 2002 to 2019.&amp;#160;The model is coupled with the Louvain-la-Neuve (LIM2) sea ice thermodynamic and dynamic numerical model and is forced by the Canadian Meteorological Centre&amp;#8217;s Global Deterministic Prediction System Reforecasts.&lt;/p&gt;&lt;p&gt;We use the model to explore the variability in ocean and sea ice characteristics along Nares Strait. The positive and negative degree days, measures of ice decay and growth, along the strait are consistent with the warming that the region is experiencing. Sea-ice production/decay did not show any significant change other than an enhanced decay during the summers of 2017-1019. Sea-ice thickness on the other hand has decreased significantly since 2007. This decrease has been more pronounced along the northern (north of Kane Basin) portion of the strait. What is more, ocean model data indicates that since 2007 the northern Nares Strait upper 100m layer has become fresher, indicating an increase in the freshwater export out of the Arctic Ocean and through the strait. The southern portion of the strait, on the other hand, has become warmer and saltier, which would be consistent with an influx of Irminger Water as proposed by previous modelling results. These changes could impact the formation and stability of the ice arch and hence the cessation of ice transport down Nares Strait as well as contributing to changes in the characteristics of the NOW.&amp;#160;&lt;/p&gt;

Rights Over the Arctic

1930 ◽  
Vol 24 (4) ◽  
pp. 703-717 ◽  
Author(s):  
W. Lakhtine
Keyword(s):  
North America ◽  
Arctic Ocean ◽  
Far East ◽  
The Other ◽  
The Arctic ◽  
The North ◽  
Arctic Regions ◽  
The Far East ◽  
The Arctic Ocean ◽  
The One

The transarctic flights of 1926 and 1928 demonstrate the possibility of establishing communication by air across the Arctic regions between Europe, on the one side, and North America and the Far East on the other. Quite aside from the saving of time owing to shorter distance, the establishment of such communication presents considerably less diiSculty than air communication over the Atlantic: a conclusion derived from the transatlantic flights of the last three years. The experience of the airship Italia in May, 1928, does not at all nullify this conclusion. It serves merely to show that the organization of transarctic communication requires special prearrangements, such aa wireless stations, meteorological stations, landing-places, air-bases, the construction of which on the shores, islands, and even on the ice of the Arctic Ocean, appears to be quite feasible. The necessity for such stations has aroused in the governments of the North countries an increased interest in the Arctic regions which heretofore has been restricted to scientific circles.

A review of aerial surveys used for estimating the numbers of barren-ground caribou in northern Canada

Polar Record ◽  
1975 ◽  
Vol 17 (111) ◽  
pp. 627-638 ◽  
Author(s):  
G. R. Parker
Keyword(s):  
Arctic Ocean ◽  
The Arctic ◽  
Hudson Bay ◽  
Northern Canada ◽  
Barren Ground ◽  
Aerial Surveys ◽  
The Arctic Ocean

The range of the barren-ground caribou in Canada includes approximately 700 000 square miles [1 812 993 sq km]: north from the forests of Manitoba and Saskatchewan to the Arctic Ocean and west from Hudson Bay to Alaska. Much of that vast expanse of stunted forests and tundra remained virtually unmapped until the ingress of the aeroplane in the 1930's.

scholarly journals Tiny But Powerful: How Tiny Amounts of Certain Gases Can Make a Big Difference in the Earth’s Climate

2021 ◽  
Vol 9 ◽  
Author(s):  
Hanna Campen ◽  
Hermann W. Bange
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Global Warming ◽  
Arctic Ocean ◽  
Dimethyl Sulfide ◽  
The Other ◽  
The Arctic ◽  
The Arctic Ocean ◽  
Extreme Cold ◽  
Earth’S Climate

Comparable to carbon dioxide, dimethyl sulfide (DMS), and carbon monoxide (CO) are tiny gases that have a great impact on our climate. Though occurring only in very small amounts in the atmosphere they are climate influencers, especially in the Arctic. The Arctic is a unique place on Earth where all life is adapted to the extreme cold. Therefore, global warming is a great threat to the Arctic. DMS and CO are produced in the Arctic Ocean and can go into the atmosphere. There, CO may enhance the warming of the Arctic. On the other hand, DMS possibly cools the atmosphere because it helps forming clouds. The processes CO and DMS are involved in, are complex and will probably alter under a changing climate. It is important to understand these processes to get an idea of the future Arctic Ocean and climate to find ways to save the Arctic.

scholarly journals Glacial erratics on the Arctic Ocean margin of North Greenland: implications for an extensive ice-shelf

1986 ◽  
Vol 35 ◽  
pp. 59-69
Author(s):  
P. R. Dawes
Keyword(s):  
Arctic Ocean ◽  
The Arctic ◽  
Northern Coast ◽  
Ice Shelf ◽  
Ice Flow ◽  
Ice Cap ◽  
Potential Source ◽  
The Arctic Ocean ◽  
Inland Ice ◽  
Made In

Glacial erratics of high-grade metamorphic and plutonic rocks occur on the northern coast of Peary Land on the edge of the Arctic Ocean. Crystalline terrain is not exposed in Peary Land; sample sites are 250 km distant from the present-day Inland Ice which covers the nearest potential source - the Greenland shield. The dominant till clasts are locally derived from a northern ice-cap that coalesced during the late Wiscon- sinian glacial maximum with the Inland Ice at about 82°30'N. Recent Quaternary mapping by the Geological Survey of Greenland failed to locate crystalline erratics in northernmost Peary Land; consequently prominence is given to early observations. The present paper describes a collection of erratics made in 1969. Conveyance mechanisms, viz. ice-cap regime (glacier or ice-shelf) contra drifting ice (icebergs or sea ice) are discussed and possible transportation paths are sum­marised. Based on rock type and mineralogy, the Greenland shield is the most likely source of the erratics and derivation from an expansion of the Inland Ice around eastern Peary Land the most logical glacial model. However, such a provenance contravenes with the presently available on-shore data which indicate an eastwards Weichselian ice flow along the coast. Instead of invoking a rather complicated glacial history for Peary Land, involving different land ice regimes, an alternative glacial model based on an extensive Greenland - Ellesmere Island ice-shelf is outlined.

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