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43-637: The Prince Christian Sound connects the Labrador Sea with the Irminger Sea . It is around 100 km (60 miles) long and it is narrow, sometimes only 500 metres (1,600 ft) wide. There is only one settlement along this sound, Aappilattoq . The long fjord system is mostly surrounded by steep mountains in general reaching over 1,200 metres (3,900 ft), one of them 2,220 metres (7,280 ft) high Many glaciers go straight into its waters where they calve icebergs. There are often strong tidal currents limiting

86-409: A breeding ground for several types of pinnipeds (including Atlantic walrus and bearded , grey , harbor , harp , hooded and ringed seals ). Several cetacean species feed in these abundant waters in early spring, including blue , fin , humpback , long-finned pilot , minke , North Atlantic right , sei and sperm whales . The sea contains one of the two primary populations of sei whales,

129-669: A high amount of anthropogenic tracers due its exposure to the atmosphere. AIW's tritium and CFC signature is observed in DSOW at the base of the Greenland continental slope. This also showed that the DSOW flowing 450 km to the south was no older than 2 years. Both the DSOW and ISOW flow around the Irminger Basin and Labrador Sea in a deep boundary current. Leaving the Greenland Sea with 2.5 Sv , its flow increases to 10 Sv south of Greenland. It

172-616: A line joining this ledge with the East extreme of Cape St. Charles (52°13'N) in Labrador. Natural Resources Canada uses a slightly different definition, putting the northern boundary of the Labrador Sea on a straight line from a headland on Killiniq Island abutting Lady Job Harbour to Cape Farewell. The Labrador Sea is about 3,400 m (1,859 fathoms ; 11,155 feet ) deep and 1,000 km (621 miles ; 540 nautical miles ) wide where it joins

215-535: 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 relatively to the surface layers, meaning it is denser, and thus sinks under the surface and remains homogeneous and unaffected by the surface fluctuations. The northern and western parts of the Labrador Sea are covered in ice between December and June. This drift ice serves as

258-567: A temperature of 2-4 °C with a salinity of 34.9-35.0 psu found at a depth between 1500 and 4000m. The NADW is a complex of several water masses formed by deep convection and overflow of dense water across the Greenland-Iceland-Scotland Ridge. The upper layers are formed by deep open ocean convection during winter. Labrador Sea Water (LSW), formed in the Labrador Sea , can reach depths of 2000 m as dense water sinks downward. Classical Labrador Sea Water (CLSW) production

301-456: Is a weather station founded by the US during World War II under the name Bluie East One . The task of the weather station was to ensure that the shipping industry had reliable data on the weather at Cape Farewell, Greenland . On 7 January 1959, when the ship MS Hans Hedtoft hit an iceberg at Cape Farvel , the radio telegraphist at the weather station at Prince Christian Sound was the first to catch

344-561: Is cold and relatively fresh, flowing below 3500 m in the DWBC and spreading inward the deep Atlantic basins. The southward spread of NADW along the Deep Western Boundary current (DWBC) can be traced by its high oxygen content, high CFCs, and density. ULSW is the major source of upper NADW. ULSW advects southward from the Labrador Sea in small eddies that mix into the DWBC. A CFC maximum associated with ULSW has been observed along 24°N in

387-531: Is dependent on preconditioning of water in the Labrador Sea from the previous year and the strength of the North Atlantic Oscillation (NAO). During a positive NAO phase, conditions exist for strong winter storms to develop. These storms freshen the surface water, and their winds increase cyclonic flow, which allows denser waters to sink. As a result, the temperature, salinity, and density vary yearly. In some years these conditions do not exist and CLSW

430-536: Is less dense than DSOW and lays above it as it flows cyclonically in the Irminger Basin. DSOW is the coldest, densest, and freshest water mass of NADW. DSOW formed behind the ridge flows over the Denmark Strait at a depth of 600m. The most significant water mass contributing to DSOW is Arctic Intermediate Water (AIW). Winter cooling and convection allow AIW to sink and pool behind the Denmark Strait. Upper AIW has

473-470: Is not formed. CLSW has characteristic potential temperature of 3 °C, salinity of 34.88 psu, and density of 34.66. Another component of LSW is the Upper Labrador Sea Water (ULSW). ULSW forms at a density lower than CLSW and has a CFC maximum between 1200 and 1500 m in the subtropical North Atlantic. Eddies of cold less saline ULSW have similar densities of warmer saltier water and flow along

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516-704: Is now buried under the continental shelves, formed during the Cretaceous . 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. 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 . Download coordinates as: The International Hydrographic Organization defines

559-536: 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 m (2.2 fathoms; 13 ft). 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

602-482: Is used to make herbal teas , are common in the area, both on the Greenland and Canadian coasts. North Atlantic Deep Water North Atlantic Deep Water ( NADW ) is a deep water mass formed in the North Atlantic Ocean . Thermohaline circulation (properly described as meridional overturning circulation) of the world's oceans involves the flow of warm surface waters from the southern hemisphere into

645-750: The Norwegian Current , which splits into the Fram Strait and Barents Sea Branch. Water from the Fram Strait recirculates, reaching a density of DSOW, sinks, and flows towards the Denmark Strait. Water flowing into the Barents Sea feeds ISOW. ISOW enters the eastern North Atlantic over the Iceland-Scotland Ridge through the Faeroe Bank Channel at a depth of 850 m, with some water flowing over

688-400: The cod fishing had already depleted the fishes' population near the Labrador and West Greenland banks, and was therefore halted in 1992. Other fishery targets include haddock , Atlantic herring , lobster , several species of flatfish , and pelagic fish , such as sand lance and capelin . They are most abundant in the southern parts of the sea. The Labrador duck was a common bird on

731-464: The 86,700 ton Eurodam , or the 137,000 ton Voyager of the Seas Ships must go slowly due to the icebergs. Prince Christian Sound has a maritime polar climate ( Köppen ET ) making borderline with subpolar oceanic climate ( Cfc ) due low annual temperature swings for its latitude and relatively high temperature in center months. Summer temperatures are way below the tree line requirements, whereas

774-494: The Atlantic Ocean. It becomes shallower, to less than 700 m (383 fathoms; 2,297 ft) towards Baffin Bay (see depth map ) and passes into the 300 km (190 mi; 160 nmi) wide Davis Strait . A 100–200 m (55–109 fathoms; 330–660 ft) deep turbidity current channel system, which is about 2–5 km (1.2–3.1 mi; 1.1–2.7 nmi) wide and 3,800 km (2,400 mi; 2,100 nmi) long, runs on

817-527: The Baffin Current is somewhat slower at about 0.2 m/s (0.66 ft/s). The Labrador Current maintains the water temperature at 0 °C (32 °F) and salinity between 30 and 34 parts per thousand. 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

860-507: The CFCs to penetrate further downward to 2000m. These minima could be tracked, and were first observed in the subtropics in the early 1990s. ISOW and DSOW flow around the Irminger Basin and DSOW entering the DWBC. These are the two lower portions of the NADW. Another CFC maximum is seen at 3500 m in the subtropics from the DSOW contribution to NADW. Some of the NADW recirculates with the northern gyre. To

903-825: The Canadian coast until the 19th century, but is now extinct. Other coastal animals include the Labrador wolf ( Canis lupus labradorius ), woodland caribou ( Rangifer tarandus caribou ), moose ( Alces alces ), black bear ( Ursus americanus ), Canada lynx ( Lynx canadensis ), red fox ( Vulpes vulpes ), Arctic fox ( Alopex lagopus ), wolverine ( G. gulo ), American mink ( Neogale vison ), North American river otter ( Lontra canadensis ), snowshoe hare ( Lepus americanus ), grouse ( Dendragapus spp.), osprey ( Pandion haliaetus ), raven ( Corvus corax ), ducks , geese , swans , partridge and pheasant . Occasionally, coastal polar bear ( Ursus maritimus ) sightings occur along

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946-512: The DWBC at 1500 m. Some of the upper ULSW recirculates into the Gulf Stream, while some remains in the DWBC. High CFCs in the subtropics indicate recirculation in the subtropics. ULSW that remains in the DWBC dilutes as it moves equatorward. Deep convection in the Labrador Sea during the late 1980s and early 1990s resulted in CLSW with a lower CFC concentration due to downward mixing. Convection allowed

989-432: The DWBC, but maintain their high CFCs. The ULSW eddies erode rapidly as they mix laterally with this warmer saltier water. The lower waters mass of NADW form from overflow of the Greenland-Iceland-Scotland Ridge. They are Iceland-Scotland Overflow Water (ISOW) and Denmark Strait Overflow Water (DSOW). The overflows are a combination of dense Arctic Ocean water (18%), modified Atlantic water (32%), and intermediate water from

1032-703: 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

1075-568: 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. The speed of the Labrador current is typically 0.3–0.5 m/s (0.98–1.64 ft/s), but can reach 1 m/s (3.3 ft/s) in some areas, whereas

1118-509: The Nordic seas (20%), that entrain and mix with other water masses (contributing 30%) as they flow over the Greenland-Iceland-Scotland Ridge. The formation of both of these waters involves the conversion of warm, salty, northward-flowing surface waters to cold, dense, deep waters behind the Greenland-Iceland-Scotland Ridge. Water flow from the North Atlantic current enters the Arctic Ocean through

1161-541: The North Atlantic. Water flowing northward becomes modified through evaporation and mixing with other water masses, leading to increased salinity. When this water reaches the North Atlantic, it cools and sinks through convection, due to its decreased temperature and increased salinity resulting in increased density. NADW is the outflow of this thick deep layer, which can be detected by its high salinity, high oxygen content, nutrient minima, high C/ C, and chlorofluorocarbons (CFCs). CFCs are anthropogenic substances that enter

1204-617: The Tropical Atlantic to the Mid and High Latitude Atlantic. In the conveyor belt model of thermohaline circulation of the world's oceans, the sinking of NADW pulls the waters of the North Atlantic drift northward. However, this is almost certainly an oversimplification of the actual relationship between NADW formation and the strength of the Gulf Stream /North Atlantic drift. NADW has

1247-678: The bottom of the sea, near its center from the Hudson Strait into the Atlantic. It is called the Northwest Atlantic Mid-Ocean Channel (NAMOC) and is one of the world's longest drainage systems of Pleistocene age. It appears as a submarine river bed with numerous tributaries and is maintained by high-density turbidity currents flowing within the levees . The water temperature varies between −1 °C (30 °F) in winter and 5–6 °C (41–43 °F) in summer. The salinity

1290-534: The formation of ice. It has many offshoots, such as Kangerluk to the north midway through the fjord, Ikeq Fjord in the south, and in the west Ilua Fjord , Ikerasaq Fjord (Akuliarutsip Imaa), Utoqqarmiut Fjord (Pamialluup Kujatinngua) and the Torsukattak Fjord . At the entrance to the East to the Strait ( 60°03′N 43°10′W  /  60.050°N 43.167°W  / 60.050; -43.167 ) there

1333-554: The largest identifiable water mass in the World Ocean . 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 (37.9–38.1 °F)) and high oxygen content compared to the layers above and below it. LSW also has

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1376-589: The limits of the Labrador Sea as follows: 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:

1419-559: The long winters are comparatively mild for its high latitude. The nearby ice sheet produces cold air which keeps summer temperatures down. Labrador Sea The Labrador Sea ( French : mer du Labrador ; Danish : Labradorhavet ) 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

1462-551: The north with Baffin Bay through the Davis Strait . It is a marginal sea of the Atlantic. 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

1505-643: The other being the Scotian Shelf . Pods of beluga (white) whales are more common further to the north, west and south (notably in Baffin Bay , where their population reaches around 20,000 animals), and further afield in Hudson Bay and the Gulf of Saint Lawrence . While somewhat rarer in the Labrador Sea—especially since the 1950s— some sightings still take place. Additionally, pods of orca are drawn to

1548-422: 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. 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. A sedimentary basin , which

1591-409: The sea by the large shoals of fish, as well as the many marine mammal species they may hunt (including other cetaceans and pinnipeds), such as harbour porpoise and Atlantic white-sided , common , striped and white-beaked dolphins . The sea is also a feeding-ground for Atlantic salmon . Shrimp fisheries began in 1978, intensifying by 2000, in addition to cod fishing. However, by the 1990s ,

1634-495: The sea, mainly further north but sometimes as far south as Conception Bay and the mouth of the Gulf of Saint Lawrence. Coastal 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. Evergreen bushes of Labrador tea , which

1677-474: The shallower Iceland-Faeroe Rise. ISOW has a low CFC concentrations and it has been estimated from these concentrations that ISOW resides behind the ridge for 45 years. As the water flows southward at the bottom of the channel, it entrains surrounding water of the eastern North Atlantic, and flows to the western North Atlantic through the Charlie-Gibbs Fracture Zone , entraining with LSW. This water

1720-503: The ship's distress signal. The weather station is today run by the International Civil Aviation Organization ICAO together with Tele Greenland . A long wooden stairway leads from the harbour up to the station with community building, power plant , residential barracks and radio aerial plants. The scenery of Prince Christian Sound attracts summer cruise ships to the area, with some vessels as large as

1763-646: The south of the gyre, NADW flows under the Gulf Stream, where it continues along the DWBC until it reaches another gyre in the subtropics. Lower North Atlantic Deep Water (LNADW), originating in the Greenland and Norwegian seas, brings high salinity, oxygen, and freon concentrations towards to the Romanche Trench , an equatorial fracture zone in the Mid-Atlantic Ridge (MAR). Found at depths around 3,600–4,000 m (11,800–13,100 ft), LNADW flow east through

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1806-599: The surface of the ocean from gas exchange with the atmosphere. This distinct composition allows its path to be traced as it mixes with Circumpolar Deep Water (CDW), which in turn fills the deep Indian Ocean and part of the South Pacific . NADW and its formation is essential to the Atlantic Meridional Overturning Circulation (AMOC), which is responsible for transporting large amounts of water, heat, salt, carbon, nutrients and other substances from

1849-515: The trench over Antarctic Bottom Water —the trench is the only opening in the MAR where inter-basin exchange is possible for these two water masses. It is believed that North Atlantic Deep Water formation has been dramatically reduced at times during the past (such as during the Younger Dryas or during Heinrich events ), and that this might correlate with a decrease in the strength of the Gulf Stream and

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