An Arctic polynya keeps whales breathing between ice sheets
Baffin Bay lies between Baffin Island and Greenland as an IHO marginal sea of the Arctic, tied to the Atlantic by Davis Strait and Labrador Sea and to the polar basin by Nares Strait. Ice locks it most of the year—except the North Water, an ~80,000-square-kilometre summer polynya near Smith Sound.
Dorset peoples gave way around AD 1200 to Thule ancestors of today’s Inuit; Norse contact may have touched these shores between the tenth and fifteenth centuries. John Davis entered in 1585; William Baffin’s 1616 Discovery voyage named Lancaster, Smith, and Jones Sounds before ice pessimism shelved the Northwest Passage hunt for two centuries until John Ross reconfirmed the charts in 1818. Canadian coast hamlets such as Arctic Bay, Pond Inlet, and Clyde River still rely on air and sealift; Nanisivik’s lead-zinc town, opened 1975, closed in 2002 and now counts zero residents.
A 1933 magnitude-7.3 quake—the largest known north of the Arctic Circle—struck offshore without major damage; five magnitude-6 events have followed, plus a 5.1 shock in April 2010. Central Baffin Basin plunges to 2,136 metres under silt, while shelves stay under 1,000 metres. West Greenland Current warms the east in summer; Baffin Island Current exports Arctic water south. Winter surface water sits below −1 °C; ice can seal shore to shore, releasing icebergs toward Newfoundland.
The North Water, known for at least 9,000 years and named by whalers, concentrates perhaps 15,000 of the bay’s ~20,000 belugas amid walrus, narwhal, seals, bowheads, and polar bears whose hunting is quota-limited. About 400 shore plants feed caribou and lemmings; USGS estimates put large Arctic hydrocarbon potential in western Greenland waters including this bay.
What looks like empty ice is a managed breathing hole for an entire polar food web.
Source: Baffin Bay
