Temperatures in Calgary crept above 30C for eight consecutive days in July, touching the highest-ever record in 1917
For those frustrated with the scorching heat in Calgary, experts have a message: embrace it as the new normal.
Meanwhile, almost the entire month of July has been hotter than average, said Alysa Pederson, a meteorologist with Environment Canada.
The risk of wildfires in the Calgary Forest Area is “very high,” according to the province on Friday.
The fires have displaced close to 1,100 people across the province with several evacuation orders in areas, including Chipewyan Lake Little and Red River Cree Nation–Garden River.
The blazes have also worsened air quality by emitting smoke — a combination of pollutants, such as particulate matter, carbon monoxide, nitrogen oxides, and volatile organic compounds (VOCs), which the province states can be harmful when inhaled.
The smoke has raised the air quality index in Calgary to level 4, suggesting people reschedule their outdoor activities if they experience coughing or throat irritation. However, the smoke, Pederson added, is higher in the sky, “so we’re not seeing it at the surface too much at this time.”
Last year was Canada’s worst year for forest wildfires, which forced evacuations in several cities and plunged air quality as temperatures rose to record highs. The phenomenon is part of a larger trend, in which extreme weather conditions are becoming more frequent.
“We’re also getting those extreme cold events like we did in mid-January this year,” Pederson added.
The reasons for the pattern are complex, but the main culprit, experts say, is the increased volatility of jet streams. The ribbons of air high above the ground travel from east to west, separating cooler air to the north and warmer air to the south.
“Storm systems develop along it, and that’s the planet’s way of trying to redistribute heat from the equator to the north and south poles,” Pederson said.
However, as greenhouse gases, driven by human activity, spread across the atmosphere, jet streams have become more volatile.
Jed Kaplan, an environmental professor at the University of Calgary, said the difference in temperatures between the poles and the equator is crucial to maintaining the stability of the jet streams. However, as it falls, the air becomes more erratic.
“In the wintertime, we notice it the most when the jet stream goes well into the states, and, therefore, we get a lot of arctic air pulled down to the surface in Alberta,” Pederson said.
Kaplan emphasized such extreme weather, which once was far and fewer in between, may now become a part of our regular experience moving forward.
“People — many of us — who are a bit older remember what things used to be like,” Kaplan added.
“What we are seeing is a different kind of summer affecting Alberta, and this is what you could imagine — year after year of record-breaking temperatures, of smoky skies — is going to become a regular occurrence.”
Regarding our immediate future, Pederson said temperatures will hover over 30 C through Tuesday, after which the city might receive cooler air — “but how much of a cool down, it remains to be seen.”