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Coordinates: 61°N 56°W / 61°N 56°W / 61; -56 (Labrador Sea)
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m added link to wiktionary:Marginal sea article which is being contradicted
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| max-depth = {{convert|4316|m|ft|0|abbr=on}}
| max-depth = {{convert|4316|m|ft|0|abbr=on}}
| reference =<ref name=bse>{{cite web|url=http://slovari.yandex.ru/%D0%9C%D0%BE%D1%80%D0%B5%20%D0%9B%D0%B0%D0%B1%D1%80%D0%B0%D0%B4%D0%BE%D1%80/%D0%93%D0%B5%D0%BE%D0%B3%D1%80%D0%B0%D1%84%D0%B8%D1%87%D0%B5%D1%81%D0%BA%D0%B8%D0%B5%20%D0%BD%D0%B0%D0%B7%D0%B2%D0%B0%D0%BD%D0%B8%D1%8F/%D0%9B%D0%B0%D0%B1%D1%80%D0%B0%D0%B4%D0%BE%D1%80/|language=Russian|title=Labrador|publisher=[[Great Soviet Encyclopedia]]}}</ref><ref name=r1>{{cite journal|author1=Wilson, R. C. L|author2=London, Geological Society of|doi=10.1144/GSL.SP.2001.187.01.05|title=Non-volcanic rifting of continental margins: a comparison of evidence from land and sea|isbn=9781862390911|year=2001|pages=77|volume=187|journal=Geological Society, London, Special Publications|url=http://books.google.com/books?id=-bsvkxVBTasC&pg=PA77}}</ref>
| reference =<ref name=bse>{{cite web|url=http://slovari.yandex.ru/%D0%9C%D0%BE%D1%80%D0%B5%20%D0%9B%D0%B0%D0%B1%D1%80%D0%B0%D0%B4%D0%BE%D1%80/%D0%93%D0%B5%D0%BE%D0%B3%D1%80%D0%B0%D1%84%D0%B8%D1%87%D0%B5%D1%81%D0%BA%D0%B8%D0%B5%20%D0%BD%D0%B0%D0%B7%D0%B2%D0%B0%D0%BD%D0%B8%D1%8F/%D0%9B%D0%B0%D0%B1%D1%80%D0%B0%D0%B4%D0%BE%D1%80/|language=Russian|title=Labrador|publisher=[[Great Soviet Encyclopedia]]}}</ref><ref name=r1>{{cite journal|author1=Wilson, R. C. L|author2=London, Geological Society of|doi=10.1144/GSL.SP.2001.187.01.05|title=Non-volcanic rifting of continental margins: a comparison of evidence from land and sea|isbn=9781862390911|year=2001|pages=77|volume=187|journal=Geological Society, London, Special Publications|url=http://books.google.com/books?id=-bsvkxVBTasC&pg=PA77}}</ref>
}}{{Contradict|about="marginal sea", as the [[:wiktionary:Marginal sea]] article defines a marginal sea as partially enclosed, but the Labrador Sea is depicted in the image instead as an open sea of the Atlantic, which is accurate as it is not partially enclosed since its land border is a north-south shore of the [[Labrador Peninsula]] and its north border is defined as south of the [[60th parallel north]] at the [[Davis Strait]] (the east and west borders are in the open Atlantic)|date=December 8, 2010}}{{DMCA|||Articles contradicting other articles}}
}}
The '''Labrador Sea''' (French: ''mer du Labrador'') is an arm of the [[North Atlantic]] [[Ocean]] between the [[Labrador Peninsula]] and [[Greenland]]. The sea is flanked by [[continental shelf|continental shelves]] to the southwest, northwest, and northeast. It connects to the north with [[Baffin Bay]] through the [[Davis Strait]].<ref name=brit>{{Cite web|url=http://www.britannica.com/eb/article-9046724/Labrador-Sea|title=Labrador Sea|author=Encyclopædia Britannica|authorlink=Encyclopædia Britannica|accessdate=2008-02-03}}</ref> It has been described as a [[marginal sea]] of the Atlantic.<ref name="Calow1999">{{cite book|author=Peter Calow|title=Blackwell's concise encyclopedia of environmental management|url=http://books.google.com/books?id=0E0LP-pPCWwC&pg=PA7|accessdate=29 November 2010|date=12 July 1999|publisher=Wiley-Blackwell|isbn=9780632049516|page=7}}</ref>
The '''Labrador Sea''' (French: ''mer du Labrador'') is an arm of the [[North Atlantic]] [[Ocean]] between the [[Labrador Peninsula]] and [[Greenland]]. The sea is flanked by [[continental shelf|continental shelves]] to the southwest, northwest, and northeast. It connects to the north with [[Baffin Bay]] through the [[Davis Strait]].<ref name=brit>{{Cite web|url=http://www.britannica.com/eb/article-9046724/Labrador-Sea|title=Labrador Sea|author=Encyclopædia Britannica|authorlink=Encyclopædia Britannica|accessdate=2008-02-03}}</ref> It has been described as a [[marginal sea]] of the Atlantic.<ref name="Calow1999">{{cite book|author=Peter Calow|title=Blackwell's concise encyclopedia of environmental management|url=http://books.google.com/books?id=0E0LP-pPCWwC&pg=PA7|accessdate=29 November 2010|date=12 July 1999|publisher=Wiley-Blackwell|isbn=9780632049516|page=7}}</ref>{{Verify source|A second source is needed since this source inaccurately claims Labrador Sea is marginal sea, but Larbrador Sea is an open sea and not even partially enclosed by an archipelago, etc. (the definition of marginal sea)|date=December 2010}}


The sea formed upon separation of the [[North American Plate]] and [[Greenland Plate]] that started about 60 million years ago and stopped about 40 million years ago. It contains one of the world's largest [[turbidity current]] channel systems, the [[Northwest Atlantic Mid-Ocean Channel]] (NAMOC), that runs for thousands of kilometers along the sea bottom toward the Atlantic Ocean.
The sea formed upon separation of the [[North American Plate]] and [[Greenland Plate]] that started about 60 million years ago and stopped about 40 million years ago. It contains one of the world's largest [[turbidity current]] channel systems, the [[Northwest Atlantic Mid-Ocean Channel]] (NAMOC), that runs for thousands of kilometers along the sea bottom toward the Atlantic Ocean.
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[[File:Artic-cultures-900-1500.png|thumb|left|150px]]
[[File:Artic-cultures-900-1500.png|thumb|left|150px]]

==History==
==History==
The Labrador Sea formed upon separation of the [[North American Plate]] and [[Greenland Plate]] that started about 60 million years ago ([[Paleocene]]) and stopped about 40 million years ago.<ref name="books.google.com">Chalmers & Pulvertaft ''In: ''Wilson, R. C. L; London, Geological Society of (2001). "Non-volcanic rifting of continental margins: a comparison of evidence from land and sea". Geological Society, London, Special Publications 187: 77. doi:10.1144/GSL.SP.2001.187.01.05. ISBN 9781862390911. http://books.google.com/books?id=-bsvkxVBTasC&pg=PA77.</ref> A [[sedimentary basin]], which is now buried under the continental shelves, formed during the [[Cretaceous]].<ref name="books.google.com"/> Onset of magmatic [[sea-floor spreading]] was accompanied by volcanic eruptions of [[picrite]]s and [[basalt]]s in the [[Paleocene]] at the Davis Strait and Baffin Bay.<ref name=r1/>
The Labrador Sea formed upon separation of the [[North American Plate]] and [[Greenland Plate]] that started about 60 million years ago ([[Paleocene]]) and stopped about 40 million years ago<ref>Chalmers & Pulvertaft ''In: ''Wilson, R. C. L; London, Geological Society of (2001). "Non-volcanic rifting of continental margins: a comparison of evidence from land and sea". Geological Society, London, Special Publications 187: 77. doi:10.1144/GSL.SP.2001.187.01.05. ISBN 9781862390911. http://books.google.com/books?id=-bsvkxVBTasC&pg=PA77.</ref>. A [[sedimentary basin]], which is now buried under the continental shelves, formed during the [[Cretaceous]]<ref>Chalmers & Pulvertaft ''In: ''Wilson, R. C. L; London, Geological Society of (2001). "Non-volcanic rifting of continental margins: a comparison of evidence from land and sea". Geological Society, London, Special Publications 187: 77. doi:10.1144/GSL.SP.2001.187.01.05. ISBN 9781862390911. http://books.google.com/books?id=-bsvkxVBTasC&pg=PA77.</ref>. Onset of magmatic [[sea-floor spreading]] was accompanied by volcanic eruptions of [[picrite]]s and [[basalt]]s in the [[Paleocene]] at the Davis Strait and Baffin Bay.<ref name=r1/>


Between about 500 BC and 1300 AD, the southern coast of the sea contained [[Dorset culture|Dorset]], [[Beothuk]] and [[Inuit]] settlements; Dorset tribes were later replaced by [[Thule people|Thule]] people.<ref>''Grønlands forhistorie'', ed. Hans Christian Gulløv, Gyldendal 2005, ISBN 87-02-01724-5</ref>
Between about 500 BC and 1300 AD, the southern coast of the sea contained [[Dorset culture|Dorset]], [[Beothuk]] and [[Inuit]] settlements; Dorset tribes were later replaced by [[Thule people|Thule]] people.<ref>''Grønlands forhistorie'', ed. Hans Christian Gulløv, Gyldendal 2005, ISBN 87-02-01724-5</ref>
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==Geography, geology and bathymetry==
==Geography, geology and bathymetry==
[[File:LabradorCurrentus-coastguard.jpg|thumb|400px|Major North Atlantic currents.]]
[[File:LabradorCurrentus-coastguard.jpg|thumb|400px|Major North Atlantic currents.]]
{{see also|East Greenland Current}}
{{seealso|East Greenland Current}}
The Labrador Sea is about {{convert|3400|m|ft|0|abbr=on}} deep and {{convert|1000|km|mi|0|abbr=on}} wide where it joins the Atlantic Ocean. It becomes shallower, to less than {{convert|700|m|ft|0|abbr=on}} towards Baffin Bay (see [[:File:IBCAO betamap.jpg|depth map]]) and passes into the 300&nbsp;km wide [[Davis Strait]].<ref name=r1/> A 100–200 m deep [[turbidity current]] channel system, which is about 2–5&nbsp;km wide and 3,800&nbsp;km long, runs on the bottom of the sea, near its center from the Hudson Strait into the Atlantic.<ref name=r1>{{cite journal|title=Ice-sheet sourced juxtaposed turbidite systems in Labrador Sea|url=http://etc.hil.unb.ca/ojs/index.php/GC/article/view/3928|journal=Geoscience Canada|volume=24|issue=1|pages=3|author8=Heisee, R and Klaucke I}}</ref><ref>{{cite journal|last1=Reinhard Hesse And Allan Rakofsky (|title=Deep-Sea Channel/Submarine-Yazoo System of the Labrador Sea: A New Deep-Water Facies Model (1)|journal=AAPG Bulletin|volume=76|year=1992|doi=10.1306/BDFF88A8-1718-11D7-8645000102C1865D}}</ref> It is called the [[Northwest Atlantic Mid-Ocean Channel]] (NAMOC) and is one of the world's longest drainage systems of Pleistocene age.<ref name=r2>{{cite book|url=http://books.google.com/books?id=LuMgcgupaJcC&pg=PA286|page=286|title=Glaciated continental margins: an atlas of acoustic images|editor= Thomas A. Davies|author=Hesse, R., Klauck, I., Khodabakhsh, S. & Ryan, W. B. F. |year=1997|work=Glacimarine drainage systems in the deep-sea: the NAMOC system of the Labrador Sea and its sibling|publisher=Springer|isbn=0412793407}}</ref> It appears as a submarine river bed with numerous tributaries and is maintained by high-density turbidity currents flowing within the [[levee]]s.<ref>{{cite book|url=http://books.google.com/books?id=-N3nidyNoJUC&pg=PA234|page=234|title=Sedimentary basins: evolution, facies, and sediment budget|author=Gerhard Einsele|publisher=Springer|year=2000|isbn=354066193X}}</ref>
The Labrador Sea is about {{convert|3400|m|ft|0|abbr=on}} deep and {{convert|1000|km|mi|0|abbr=on}} wide where it joins the Atlantic Ocean. It becomes shallower, to less than {{convert|700|m|ft|0|abbr=on}} towards Baffin Bay (see [[:File:IBCAO betamap.jpg|depth map]]) and passes into the 300 km wide [[Davis Strait]].<ref name=r1/> A 100–200 m deep [[turbidity current]] channel system, which is about 2–5 km wide and 3,800 km long, runs on the bottom of the sea, near its center from the Hudson Strait into the Atlantic.<ref name=r1>{{cite journal|title=Ice-sheet sourced juxtaposed turbidite systems in Labrador Sea|url=http://etc.hil.unb.ca/ojs/index.php/GC/article/view/3928|journal=Geoscience Canada|volume=24|issue=1|pages=3|author8=Heisee, R and Klaucke I}}</ref><ref>{{cite journal|last1=Reinhard Hesse And Allan Rakofsky (|title=Deep-Sea Channel/Submarine-Yazoo System of the Labrador Sea: A New Deep-Water Facies Model (1)|journal=AAPG Bulletin|volume=76|year=1992|doi=10.1306/BDFF88A8-1718-11D7-8645000102C1865D}}</ref> It is called the [[Northwest Atlantic Mid-Ocean Channel]] (NAMOC) and is one of the world's longest drainage systems of Pleistocene age.<ref name=r2>{{cite book|url=http://books.google.com/books?id=LuMgcgupaJcC&pg=PA286|page=286|title=Glaciated continental margins: an atlas of acoustic images|editor= Thomas A. Davies|author=Hesse, R., Klauck, I., Khodabakhsh, S. & Ryan, W. B. F. |year=1997|work=Glacimarine drainage systems in the deep-sea: the NAMOC system of the Labrador Sea and its sibling|publisher=Springer|isbn=0412793407}}</ref> It appears as a submarine river bed with numerous tributaries and is maintained by high-density turbidity currents flowing within the [[levee]]s.<ref>{{cite book|url=http://books.google.com/books?id=-N3nidyNoJUC&pg=PA234|page=234|title=Sedimentary basins: evolution, facies, and sediment budget|author=Gerhard Einsele|publisher=Springer|year=2000|isbn=354066193X}}</ref>


The water temperature varies between –1 °C in winter and 5–6 °C in summer. The salinity is relatively low, at 31–34.9 parts per thousand. Two-thirds of the sea is covered in ice in winter. Tides are [[Earth tide|semi-diurnal]] (i.e. occur twice a day), reaching 4 meters.<ref name=bse/>
The water temperature varies between –1 °C in winter and 5–6 °C in summer. The salinity is relatively low, at 31–34.9 parts per thousand. Two-thirds of the sea is covered in ice in winter. Tides are [[Earth tide|semi-diurnal]] (i.e. occur twice a day), reaching 4 meters.<ref name=bse/>


There is an anticlockwise water circulation in the sea. It is initiated by the [[East Greenland Current]] and continued by the [[West Greenland Current]], which brings warmer, more saline waters northwards, along the Greenland coasts up to the Baffin Bay. Then, the [[Baffin Island Current]] and [[Labrador Current]] transport cold and less saline water southward along the Canadian coast. These currents carry numerous icebergs and therefore hinder navigation and exploration of the gas fields beneath the sea bed.<ref name=brit/><ref name=can>{{Cite web|url=http://www.thecanadianencyclopedia.com/index.cfm?PgNm=TCE&Params=A1ARTA0004438|title=Labrador Sea|author=The Canadian Encyclopedia|authorlink=The Canadian Encyclopedia|accessdate=2008-02-03}}</ref> The speed of the Labrador current is typically 0.3–0.5&nbsp;m/s, but can reach 1&nbsp;m/s in some areas,<ref>{{cite journal|author=Petrie, B., and A. Isenor|year=1985|url=http://www.cmos.ca/Ao/articles/v230301.pdf |title=The near-surface circulation and exchange in the Newfoundland Grand Banks region|journal=Atmosphere-Ocean|volume=23|issue=3|pages=209–227}}</ref> whereas the Baffin Current is somewhat slower at about 0.2&nbsp;m/s.<ref>{{Cite web|url=http://www.britannica.com/EBchecked/topic/48703/Baffin-Island-Current|title=Baffin Current|author=Encyclopædia Britannica|authorlink=Encyclopædia Britannica|accessdate=2010-02-03}}</ref> The Labrador Current maintains the water temperature at 0 °C and salinity between 30 and 34 parts per thousand.<ref>{{Cite web|url=http://www.britannica.com/EBchecked/topic/327001/Labrador-Current|title=Labrador Current|author=Encyclopædia Britannica|authorlink=Encyclopædia Britannica|accessdate=2010-02-03}}</ref>
There is an anticlockwise water circulation in the sea. It is initiated by the [[East Greenland Current]] and continued by the [[West Greenland Current]], which brings warmer, more saline waters northwards, along the Greenland coasts up to the Baffin Bay. Then, the [[Baffin Island Current]] and [[Labrador Current]] transport cold and less saline water southward along the Canadian coast. These currents carry numerous icebergs and therefore hinder navigation and exploration of the gas fields beneath the sea bed.<ref name=brit/><ref name=can>{{Cite web|url=http://www.thecanadianencyclopedia.com/index.cfm?PgNm=TCE&Params=A1ARTA0004438|title=Labrador Sea|author=The Canadian Encyclopedia|authorlink=The Canadian Encyclopedia|accessdate=2008-02-03}}</ref> The speed of the Labrador current is typically 0.3–0.5 m/s, but can reach 1 m/s in some areas,<ref>{{cite journal|author=Petrie, B., and A. Isenor|year=1985|url=http://www.cmos.ca/Ao/articles/v230301.pdf |title=The near-surface circulation and exchange in the Newfoundland Grand Banks region|journal=Atmosphere-Ocean|volume=23|issue=3|pages=209–227}}</ref> whereas the Baffin Current is somewhat slower at about 0.2 m/s.<ref>{{Cite web|url=http://www.britannica.com/EBchecked/topic/48703/Baffin-Island-Current|title=Baffin Current|author=Encyclopædia Britannica|authorlink=Encyclopædia Britannica|accessdate=2010-02-03}}</ref> The Labrador Current maintains the water temperature at 0 °C and salinity between 30 and 34 parts per thousand.<ref>{{Cite web|url=http://www.britannica.com/EBchecked/topic/327001/Labrador-Current|title=Labrador Current|author=Encyclopædia Britannica|authorlink=Encyclopædia Britannica|accessdate=2010-02-03}}</ref>


The sea provides a significant part of the [[North Atlantic Deep Water]] (NADW) – a cold water mass that flows at great depth along the western edge of the North Atlantic, spreading out to form the largest identifiable water mass in the [[World Ocean]].<ref>{{cite book|url=http://books.google.com/books?id=JMI6AAAAIAAJ&pg=PA179|page=179|title=Earth systems: processes and issues|author=Wallace Gary Ernst|publisher=Cambridge University Press|year=2000|isbn=0521478952}}</ref> The NADW consists of three parts of different origin and salinity, and the top one, the Labrador Sea Water (LSW), is formed in the Labrador Sea. This part occurs at a medium depth and has a relatively low salinity (34.84–34.89 parts per thousand), low temperature (3.3–3.4 °C) and high oxygen content compared to the layers above and below it. LSW also has a relatively low vorticity, i.e. the tendency to form vortices, than any other water in North Atlantic that reflects its high homogeneity. It has a [[potential density]] of 27.76–27.78&nbsp;mg/cm<sup>3</sup> relatively to the surface layers, meaning it is denser, and thus sinks under the surface and remains homogeneous and unaffected by the surface fluctuations.<ref>{{cite journal|last1=Talley|first1=L.D.|last2=McCartney|first2=M.S.|title=Distribution and Circulation of Labrador Sea Water|doi=10.1175/1520-0485(1982)012<1189:DACOLS>2.0.CO;2|issn=1520-0485|year=1982|pages=1189|volume=12|journal=Journal of Physical Oceanography|url=ftp://gyre.ucsd.edu/nonpub/talley/papers/1980s/talley_mccartney_jpo_1982.pdf}}</ref>
The sea provides a significant part of the [[North Atlantic Deep Water]] (NADW) – a cold water mass that flows at great depth along the western edge of the North Atlantic, spreading out to form the largest identifiable water mass in the [[World Ocean]].<ref>{{cite book|url=http://books.google.com/books?id=JMI6AAAAIAAJ&pg=PA179|page=179|title=Earth systems: processes and issues|author=Wallace Gary Ernst|publisher=Cambridge University Press|year=2000|isbn=0521478952}}</ref> The NADW consists of three parts of different origin and salinity, and the top one, the Labrador Sea Water (LSW), is formed in the Labrador Sea. This part occurs at a medium depth and has a relatively low salinity (34.84–34.89 parts per thousand), low temperature (3.3–3.4 °C) and high oxygen content compared to the layers above and below it. LSW also has a relatively low vorticity, i.e. the tendency to form vortices, than any other water in North Atlantic that reflects its high homogeneity. It has a [[potential density]] of 27.76–27.78 mg/cm<sup>3</sup> relatively to the surface layers, meaning it is denser, and thus sinks under the surface and remains homogeneous and unaffected by the surface fluctuations.<ref>{{cite journal|last1=Talley|first1=L.D.|last2=McCartney|first2=M.S.|title=Distribution and Circulation of Labrador Sea Water|doi=10.1175/1520-0485(1982)012<1189:DACOLS>2.0.CO;2|issn=1520-0485|year=1982|pages=1189|volume=12|journal=Journal of Physical Oceanography|url=ftp://gyre.ucsd.edu/nonpub/talley/papers/1980s/talley_mccartney_jpo_1982.pdf}}</ref>


==Fauna==
==Fauna==
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==Flora==
==Flora==
Costal vegetation includes [[black spruce]] (''Picea mariana''), [[tamarack]], [[white spruce]] (''P. glauca''), [[dwarf birch]] (''Betula'' spp.), [[aspen]], [[willow]] (''Salix'' spp.), ericaceous shrubs (''[[Ericaceae]]''), [[cottongrass]] (''Eriophorum'' spp.), [[sedge]] (''Carex'' spp.), lichens and moss.<ref name=f/> Evergreen bushes of [[Labrador tea]], which is used to make [[herbal tea]], are common in the area, both on the Greenland and Canadian coasts.<ref>[http://www.fs.fed.us/global/iitf/pdf/shrubs/Ledum%20groenlandicum.pdf Ledum groenlandicum Oeder – Labrador Tea]</ref>
Costal vegetation includes [[black spruce]] (''Picea mariana''), [[tamarack]], [[white spruce]] (''P. glauca''), [[dwarf birch]] (''Betula'' spp.), [[aspen]], [[willow]] (''Salix'' spp.), ericaceous shrubs (''[[Ericaceae]]''), [[cottongrass]] (''Eriophorum'' spp.), [[sedge]] (''Carex'' spp.), lichens and moss.<ref name=f/> Evergreen bushes of [[Labrador tea]], which is used to make [[herbal tea]], are common in the area, both on the Greenland and Canadian coasts.<ref>[http://www.fs.fed.us/global/iitf/pdf/shrubs/Ledum%20groenlandicum.pdf Ledum groenlandicum Oeder – Labrador Tea]</ref>

==References==
==References==
{{reflist|2}}
{{reflist|2}}

Revision as of 15:37, 9 December 2010

Labrador Sea
Basin countriesCanada, Greenland
Max. lengthca. 1,000 km (621 mi)
Max. widthca. 900 km (559 mi)
Surface area841,000 km2 (324,700 sq mi)
Average depth1,898 m (6,227 ft)
Max. depth4,316 m (14,160 ft)
References[1][2]

The Labrador Sea (French: mer du Labrador) is an arm of the North Atlantic Ocean between the Labrador Peninsula and Greenland. The sea is flanked by continental shelves to the southwest, northwest, and northeast. It connects to the north with Baffin Bay through the Davis Strait.[3] It has been described as a marginal sea of the Atlantic.[4][verification needed]

The sea formed upon separation of the North American Plate and Greenland Plate that started about 60 million years ago and stopped about 40 million years ago. It contains one of the world's largest turbidity current channel systems, the Northwest Atlantic Mid-Ocean Channel (NAMOC), that runs for thousands of kilometers along the sea bottom toward the Atlantic Ocean.

The Labrador Sea is a major source of the North Atlantic Deep Water, a cold water mass that flows at great depth along the western edge of the North Atlantic, spreading out to form the largest identifiable water mass in the World Ocean.

History

The Labrador Sea formed upon separation of the North American Plate and Greenland Plate that started about 60 million years ago (Paleocene) and stopped about 40 million years ago[5]. A sedimentary basin, which is now buried under the continental shelves, formed during the Cretaceous[6]. Onset of magmatic sea-floor spreading was accompanied by volcanic eruptions of picrites and basalts in the Paleocene at the Davis Strait and Baffin Bay.[2]

Between about 500 BC and 1300 AD, the southern coast of the sea contained Dorset, Beothuk and Inuit settlements; Dorset tribes were later replaced by Thule people.[7]

Extent

The International Hydrographic Organization defines the limits of the Labrador Sea as follows:[8]

On the North: the South limit of Davis Strait [The parallel of 60° North between Greenland and Labrador].

On the East: a line from Cape St. Francis 47°45′N 52°27′W / 47.750°N 52.450°W / 47.750; -52.450 (Cape St. Francis) (Newfoundland) to Cape Farewell (Greenland).

On the West: the East Coast of Labrador and Newfoundland and the Northeast limit of the Gulf of St. Lawrence – a line running from Cape Bauld (North point of Kirpon Island, 51°40′N 55°25′W / 51.667°N 55.417°W / 51.667; -55.417 (Cape Bauld)) to the East extreme of Belle Isle and on to the Northeast Ledge (52°02′N 55°15′W / 52.033°N 55.250°W / 52.033; -55.250 (Belle Isle)). Thence a line joining this ledge with the East extreme of Cape St. Charles (52°13'N) in Labrador.

Geography, geology and bathymetry

Major North Atlantic currents.

The Labrador Sea is about 3,400 m (11,155 ft) deep and 1,000 km (621 mi) wide where it joins the Atlantic Ocean. It becomes shallower, to less than 700 m (2,297 ft) towards Baffin Bay (see depth map) and passes into the 300 km wide Davis Strait.[2] A 100–200 m deep turbidity current channel system, which is about 2–5 km wide and 3,800 km long, runs on the bottom of the sea, near its center from the Hudson Strait into the Atlantic.[2][9] It is called the Northwest Atlantic Mid-Ocean Channel (NAMOC) and is one of the world's longest drainage systems of Pleistocene age.[10] It appears as a submarine river bed with numerous tributaries and is maintained by high-density turbidity currents flowing within the levees.[11]

The water temperature varies between –1 °C in winter and 5–6 °C in summer. The salinity is relatively low, at 31–34.9 parts per thousand. Two-thirds of the sea is covered in ice in winter. Tides are semi-diurnal (i.e. occur twice a day), reaching 4 meters.[1]

There is an anticlockwise water circulation in the sea. It is initiated by the East Greenland Current and continued by the West Greenland Current, which brings warmer, more saline waters northwards, along the Greenland coasts up to the Baffin Bay. Then, the Baffin Island Current and Labrador Current transport cold and less saline water southward along the Canadian coast. These currents carry numerous icebergs and therefore hinder navigation and exploration of the gas fields beneath the sea bed.[3][12] The speed of the Labrador current is typically 0.3–0.5 m/s, but can reach 1 m/s in some areas,[13] whereas the Baffin Current is somewhat slower at about 0.2 m/s.[14] The Labrador Current maintains the water temperature at 0 °C and salinity between 30 and 34 parts per thousand.[15]

The sea provides a significant part of the North Atlantic Deep Water (NADW) – a cold water mass that flows at great depth along the western edge of the North Atlantic, spreading out to form the largest identifiable water mass in the World Ocean.[16] The NADW consists of three parts of different origin and salinity, and the top one, the Labrador Sea Water (LSW), is formed in the Labrador Sea. This part occurs at a medium depth and has a relatively low salinity (34.84–34.89 parts per thousand), low temperature (3.3–3.4 °C) and high oxygen content compared to the layers above and below it. LSW also has a relatively low vorticity, i.e. the tendency to form vortices, than any other water in North Atlantic that reflects its high homogeneity. It has a potential density of 27.76–27.78 mg/cm3 relatively to the surface layers, meaning it is denser, and thus sinks under the surface and remains homogeneous and unaffected by the surface fluctuations.[17]

Fauna

The northern and western parts of the Labrador Sea are covered in ice between December and June. The drift ice serves as a breeding ground for seals in early spring. The sea is a also a feeding ground for Atlantic salmon and several marine mammal species. Shrimp fisheries began in 1978 and intensified toward 2000, as well as cod fishing. However, the cod fishing rapidly depleted the fish population in the 1990s near the Labrador and West Greenland banks and was therefore halted in 1992.[12] Other fishery targets include haddock, Atlantic herring, lobster and several species of flatfish and pelagic fish such as sand lance and capelin. They are most abundant in the southern parts of the sea.[18]

Beluga whales, while abundant to the north, in the Baffin Bay, where their population reaches 20,000, are rare in the Labrador Sea, especially since 1950s.[19] The sea contains one of the two major stocks of Sei whales, the other one being the Scotian Shelf. Also common are minke and bottlenose whales.[20]

File:LabradorTea.jpg
Close up of a Labrador Tea flower.

The Labrador Duck was a common bird on the Canadian coast until 19th century, but is now extinct.[21] Other coastal animals include the Labrador Wolf (Canis lupus labradorius),[22][23] caribou (Rangifer spp.), moose (Alces alces), black bear (Ursus americanus), red fox (Vulpes vulpes), arctic fox (Alopex lagopus), wolverine, snowshoe hare (Lepus americanus), grouse (Dendragapus spp.), osprey (Pandion haliaetus), raven (Corvus corax), ducks, geese, partridge and American wild pheasant.[24][25]

Flora

Costal vegetation includes black spruce (Picea mariana), tamarack, white spruce (P. glauca), dwarf birch (Betula spp.), aspen, willow (Salix spp.), ericaceous shrubs (Ericaceae), cottongrass (Eriophorum spp.), sedge (Carex spp.), lichens and moss.[25] Evergreen bushes of Labrador tea, which is used to make herbal tea, are common in the area, both on the Greenland and Canadian coasts.[26]

References

  1. ^ a b "Labrador" (in Russian). Great Soviet Encyclopedia.
  2. ^ a b c d Wilson, R. C. L; London, Geological Society of (2001). "Non-volcanic rifting of continental margins: a comparison of evidence from land and sea". Geological Society, London, Special Publications. 187: 77. doi:10.1144/GSL.SP.2001.187.01.05. ISBN 9781862390911. Cite error: The named reference "r1" was defined multiple times with different content (see the help page).
  3. ^ a b Encyclopædia Britannica. "Labrador Sea". Retrieved 2008-02-03.
  4. ^ Peter Calow (12 July 1999). Blackwell's concise encyclopedia of environmental management. Wiley-Blackwell. p. 7. ISBN 9780632049516. Retrieved 29 November 2010.
  5. ^ Chalmers & Pulvertaft In: Wilson, R. C. L; London, Geological Society of (2001). "Non-volcanic rifting of continental margins: a comparison of evidence from land and sea". Geological Society, London, Special Publications 187: 77. doi:10.1144/GSL.SP.2001.187.01.05. ISBN 9781862390911. http://books.google.com/books?id=-bsvkxVBTasC&pg=PA77.
  6. ^ Chalmers & Pulvertaft In: Wilson, R. C. L; London, Geological Society of (2001). "Non-volcanic rifting of continental margins: a comparison of evidence from land and sea". Geological Society, London, Special Publications 187: 77. doi:10.1144/GSL.SP.2001.187.01.05. ISBN 9781862390911. http://books.google.com/books?id=-bsvkxVBTasC&pg=PA77.
  7. ^ Grønlands forhistorie, ed. Hans Christian Gulløv, Gyldendal 2005, ISBN 87-02-01724-5
  8. ^ "Limits of Oceans and Seas, 3rd edition" (PDF). International Hydrographic Organization. 1953. Retrieved 6 February 2010.
  9. ^ Reinhard Hesse And Allan Rakofsky ( (1992). "Deep-Sea Channel/Submarine-Yazoo System of the Labrador Sea: A New Deep-Water Facies Model (1)". AAPG Bulletin. 76. doi:10.1306/BDFF88A8-1718-11D7-8645000102C1865D.
  10. ^ Hesse, R., Klauck, I., Khodabakhsh, S. & Ryan, W. B. F. (1997). Thomas A. Davies (ed.). Glaciated continental margins: an atlas of acoustic images. Springer. p. 286. ISBN 0412793407. {{cite book}}: |work= ignored (help)CS1 maint: multiple names: authors list (link)
  11. ^ Gerhard Einsele (2000). Sedimentary basins: evolution, facies, and sediment budget. Springer. p. 234. ISBN 354066193X.
  12. ^ a b The Canadian Encyclopedia. "Labrador Sea". Retrieved 2008-02-03.
  13. ^ Petrie, B., and A. Isenor (1985). "The near-surface circulation and exchange in the Newfoundland Grand Banks region" (PDF). Atmosphere-Ocean. 23 (3): 209–227.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  14. ^ Encyclopædia Britannica. "Baffin Current". Retrieved 2010-02-03.
  15. ^ Encyclopædia Britannica. "Labrador Current". Retrieved 2010-02-03.
  16. ^ Wallace Gary Ernst (2000). Earth systems: processes and issues. Cambridge University Press. p. 179. ISBN 0521478952.
  17. ^ Talley, L.D.; McCartney, M.S. (1982). "Distribution and Circulation of Labrador Sea Water" (PDF). Journal of Physical Oceanography. 12: 1189. doi:10.1175/1520-0485(1982)012<1189:DACOLS>2.0.CO;2. ISSN 1520-0485.
  18. ^ National Research Council (U.S.) (1981). Maritime services to support polar resource development. pp. 6–7.
  19. ^ COSEWIC Assessment and Update Status Report on the Beluga Whale
  20. ^ Anthony Bertram Dickinson, Chesley W. Sanger (2005). Twentieth-century shore-station whaling in Newfoundland and Labrador. McGill-Queen's Press - MQUP. pp. 16–17. ISBN 0773528814.
  21. ^ Ducher, William (1894). "The Labrador Duck – another specimen, with additional data respecting extant specimens" (PDF). Auk. 11: 4–12.
  22. ^ E. A. Goldman (1937). "The Wolves of North America". Journal of Mammalogy. 18 (1): 37–45. doi:10.2307/1374306.
  23. ^ G.R. Parker and S. Luttich (1986). "Characteristics of the Wolf (Canis lupus lubrudorius Goldman) in Northern Quebec and Labrador" (PDF). Arctic. 39 (2): 145–149.
  24. ^ Anonymous, (2006). The Moravians in Labrador. pp. 9–11. ISBN 1406805122.{{cite book}}: CS1 maint: extra punctuation (link)
  25. ^ a b Eastern Canadian Shield taiga (NA0606), WorldWildLife.org
  26. ^ Ledum groenlandicum Oeder – Labrador Tea

61°N 56°W / 61°N 56°W / 61; -56 (Labrador Sea)