A young ocean arm helps drive North Atlantic deep water
The Labrador Sea opens between Labrador and Greenland as a North Atlantic arm born when North America and Greenland plates split from about 60 to 40 million years ago. Cold, dense water formed here helps feed the North Atlantic Deep Water conveyor.
Where it meets the open Atlantic the basin plunges to about 3,400 metres and spans roughly 1,000 kilometres; toward Baffin Bay depths fall under 700 metres. Continental shelves border both sides, hiding a sedimentary basin that formed back in the Cretaceous, and a huge network of submarine canyons, often shortened to NAMOC, carries turbidity currents across the floor. IHO limits run along 60°N at Davis Strait’s south edge and from Newfoundland’s Cape St. Francis to Greenland’s Cape Farewell. Natural Resources Canada draws the northern edge differently, from Killiniq Island to Cape Farewell.
Water circles anticlockwise: the East and then West Greenland currents carry warmer, saltier water north toward Baffin Bay before the Baffin Island and Labrador currents bring it back south. Sinking here supplies a large share of North Atlantic Deep Water, the biggest identifiable water mass in the world ocean. Winter temperatures near −1 °C and summer peaks of 5–6 °C pair with relatively low salinity (31–34.9‰). Ice covers about two-thirds of the surface in winter, locking harbours and shifting hunting calendars.
Between December and June drift ice in the north and west becomes a nursery for Atlantic walrus and for bearded, grey, harbour, harp, hooded and ringed seals. From roughly 500 BCE to 1300 CE, Dorset, Beothuk, and Inuit communities used the southern coasts before Thule successors replaced Dorset cultures along the same strandlines.
Atlantic salmon still feed here; shrimp fisheries began in 1978 and intensified by 2000 even as 1990s collapses emptied nearby cod grounds. The extinct Labrador duck once lived along its Canadian shores, which still support wolves, caribou and moose.
Source: Labrador Sea
