Amid reports of a late June heat wave in Europe this year, I thought I would check out the temperature in Churchill, Manitoba – where sea ice off the coast has been rather slow to melt this year with no reports yet of polar bears onshore. It turns out that Churchill has fairly often seen very hot weather (around 900F/300C) for a few days at this time of year but 2019 has certainly not been one of them. Temperatures in Churchill on 28 June this year were about 40 degress F below previous highs (more than 15 degrees C) according to online Environment Canada weather comparison reports that go back to 1943 (although their records for Churchill go back to 1929).
High for 28 June 2019: 44.4 F/7.1 C
Hottest year, late June: 90.0 F/32.2 C on 29 June 1984 [also 87.8 F/30.6 C on 26 June 1967]
Hottest year, early July: 93.0 F/33.9 C on 4 July, 1975 [also 91.0 F/32.8 C on 3 July 1976]
Bottom line: It is appropriate to scoff at anyone who claims it never got hot in the Arctic before sea ice declined markedly around the turn of the 21st century. For Churchill (self-proclaimed Polar Bear Capital of the World), there are plenty of records of brief spells of hot weather in late spring/early summer (as well as in other months) that go back to the decades when sea ice conditions were supposedly ideal for polar bears.
A part-time Arctic researcher eager for media attention suggested earlier today that the ice entrapment of narwhals in 2008 and again in 2015 at Pond Inlet (that made headlines around the world) was the result of “sudden changes in temperature” caused by climate change. This grossly misleading claim ignores the facts: ice entrapment of narwhals is an entirely natural feature of the Arctic that has been known about for hundreds of years.
“Narwhals: the ‘giant unicorn of the sea’ at risk from climate change” (CBC, 13 August 2016), a print version of a CBC Radio interview with Clint Wright that aired 8 August 2016. Wright is the general manager at the Vancouver Aquarium and apparently has “joined a team of researchers to tag and study” narwhals for several years – but does not seem to know much about the history or circumstances of natural ice entrapment.
Ice entrapment of small whales is nothing new. The first formally documented incident – in English – occurred in 1915 (Porsild 1918) and the phenomenon has probably occurred as long as there has been ice in the Arctic (millions of years).
Animals routinely become trapped in a few specific areas due to local geography: when ice that forms in the north moves south quickly, it blocks the entrances to inlets or coastal bays that still have open water. The presence of the pack ice causes nearby temperatures to drop quickly. Rapid development of ice on the bay proceeds from the mouth toward the head of the bay. Any whales present cannot escape to open water and will eventually die or be eaten.
Pond Inlet at the north end of Baffin Island is one such place but Disko Bay in western Greenland is another. In fact, Pond Inlet and Disko Bay are almost identical in geographic layout even though they lie on opposite sides of Baffin Bay, so it’s not surprising that both are locations of repeated entrapment events.
Three highly informative journal articles on the phenomenon of ice entrapment of narwhals and beluga are open access documents that reveal some fascinating details of such incidents, including polar bear predation on trapped whales. h/t T. Nelson Continue reading
Posted in History, Life History, Sea ice habitat, Uncategorized
Tagged Arctic, baffin bay, beluga, climate, climate change, Clint Wright, Disko Bay, entrapment, facts, global warming, narwhal, polar bear, Pond Inlet, predation, prey, risk, sea ice, threatened, trapped, unicorn, Vancouver Aquarium, weather, whales