the “heat dome” shatters new records

Schools and vaccination centers against Covid-19 closed, Olympic selection tests staggered and residents taking refuge in centers of “Refreshment” : Western Canada and the United States broke new records on Monday, June 28 “Historical” of temperatures caused by a “heat dome” of extremely rare intensity.

In Portland (Oregon) and Seattle (Washington State), two large cities in the northwest of the United States known for their cold and humid climates, the temperature reached its highest level ever recorded since the beginning of the archives, in 1940.

It was 46.1 degrees Celsius at the Portland airport Monday afternoon (after a record 44.4 degrees the day before) and 41.6 degrees at Seattle, according to readings by the US Weather Service ( NWS).

The heat wave will persist throughout the week

But it is western Canada that still holds the palm. In Lytton, a village northeast of Vancouver, the record set Sunday was broken again: the mercury climbed Monday to 47.9 degrees. The highest temperature ever recorded in Canada before this heat wave was 45 degrees in 1937.

In the region, air conditioners and fans are out of stock. Cities have opened refreshment centers. Vaccination campaigns against Covid-19 have been canceled, and schools closed.

“A prolonged, dangerous and historic heat wave will persist throughout this week”, warned Environment Canada, issuing alerts for British Columbia, Alberta and parts of Saskatchewan, the Northwest Territories and the Yukon, bordering Alaska.

“We are the second coldest country in the world and the snowiest”, so not used to this “Desert heat, very dry”David Phillips, Environment Canada’s chief climatologist, told AFP on Monday.

“This level of heat is extremely dangerous”

On the other side of the border, too, Americans are suffering from the sweltering temperatures in the northwestern states. “This level of heat is extremely dangerous”, warned the NWS on Monday.

A Seattle market, the Ballard Farmers Market, had to close earlier, arguably a first ” because of the heat “, its director Doug Farr told AFP. “Most of the time it’s because of the snow. “

The Amazon group announced Monday that it was opening part of its Seattle headquarters to the public to make it a refreshment point with a capacity of a thousand seats. Many homes do not have air conditioners in this generally very temperate city.

The average temperature for June in Seattle is 19 degrees Celsius. “At 21 degrees, it’s a good day, everyone is outside in shorts and a T-shirt, but this is becoming absurd”, said a Seattle resident interviewed by AFP, saying he had “The impression of being in the desert”.

600 hectares burned by the “Lava Fire”

The extreme heat, combined with an intense drought in the American West, favored several fires that broke out over the weekend. The « Lava Fire », on the edge of Oregon and California, had already burned some 600 hectares Monday morning, forcing the authorities to evacuate some residents and close a national road.

This heat wave is explained by a phenomenon called “Heat dome” : High pressures trap warm air in the area. What to arouse « graves » health concerns, notes Canadian David Phillips. Especially since it has lasted for several days.

The intensity of this “Heat dome” is “So statistically rare that one might only expect it once every few thousand years on average”, wrote the weather specialists of the “Washington Post”. “But human-induced climate change has made these kinds of exceptional events more likely. “

According to Nick Bond, climatologist at the University of Washington, climate change is a factor here, yes, but “Secondary”. “The main element is this very unusual weather pattern” of the heat dome, he told AFP. This “Being said, climate change is real, our temperatures have warmed up here”, which “Made this heat episode even more severe”.