Quick links
heat dome
DCHP-3 (Mar 2023)
n. — Weather, Climate change
a weather system that traps hot air over an area of land for a prolonged period of time.
Type: 5. Frequency — The term heat dome was introduced to the mainstream Canadian lexicon by meteorologists in 2011, in order to characterize the unprecedentedly massive and long-lasting heat wave that spread across a wide swathe of the North American landscape, from the Rockies all the way to the Laurentians (see the 2011 quotation).
The term stuck (see Chart 1), living quietly in the background of various weather reports throughout the 2010s (see the 2014 and 2019 quotations). As a result of human-caused climate change, however, heat domes are becoming more frequent during Canadian summers (see the 2016 and 2020 quotations), where the term is currently most prevalent (see Chart 1). The advent of heat domes has placed both humans and wildlife under increased stress, leading to numerous fatalities in particularly extreme cases such as the summer of 2021 in British Columbia (see the 2021, 2022 and 2023 quotations).
The term stuck (see Chart 1), living quietly in the background of various weather reports throughout the 2010s (see the 2014 and 2019 quotations). As a result of human-caused climate change, however, heat domes are becoming more frequent during Canadian summers (see the 2016 and 2020 quotations), where the term is currently most prevalent (see Chart 1). The advent of heat domes has placed both humans and wildlife under increased stress, leading to numerous fatalities in particularly extreme cases such as the summer of 2021 in British Columbia (see the 2021, 2022 and 2023 quotations).
Quotations
2011
And back here at home, millions of Canadians are sweltering through a heat wave, and if you're finding this sticky weather hard to take, you might want to find ways to adapt. Forecasters are talking about something called a heat dome. It's going to sit around in mid-continent for quite a while, keeping people from the prairies all the way to Montreal mopping their brows and finding relief wherever they can.
2014
What happened in Russia is almost beyond imagination. It is almost the stuffof science fiction. The weakening of the European jet stream caused by reduced snow and sea ice cover led to the creation of a heat dome in northern Siberia. In July 2013 hundreds of wildfires broke out that were so hot they melted the permafrost beneath the burning forests, creating methane releases from the thawing tundra that added fuel to the fires. Then, in early August, in the midst of what was coming to resemble a virtual firestorm, three atmospheric rivers collided over the region and within four days created a flood that covered a million square kilometres. Again we see floods and fires of a magnitude seldom experienced before in the same basin in the same year. But we also see something much darker. It appears we are melting the frozen lid of the jar that contains much of the world's methane. Compared to this, opening Pandora's box is like unwrapping a Christmas present.
2016
London has experienced three straight months of above-average temperatures this summer. There have already been more days with temperatures over 30 C this summer than last, including a mid-July "heat dome" that caused Environment Canada to issue 16 heat warnings across southern Ontario, with above-30 C lasting for three to four days. The Middlesex-London Health Unit has issued six heat warnings this summer -- up from one last summer -- the latest occurring in mid-August.
2018
According to Saltwire meteorologist Cindy Day, Proctor's water woes can be blamed on a heat dome.
The large dome of hot air has been held over Atlantic Canada all summer by a jet stream whose course has been farther north than usual.
That dome of heat has prevented the normal track of weather systems through the area.
2019
A main cause for the massive early season heat wave is a pair of powerful high-pressure systems. One is near Greenland, and the other is over north-central Europe. As they become linked and flex over coming days, forming a massive heat dome, they'll also act to block a low-pressure system to their south, which would draw cooler air over Europe.
"Europe is currently under historically strong upper ridge," Mika Rantanen, a meteorologist in Finland, tweeted Wednesday. An upper ridge is the technical term for this extensive zone of high pressure or heat dome.
2020
Meteorologist Dan Kulak said the last week of July tends to be one of the hottest weeks of the year nearly ever year, due to a "heat dome" weather system that travels north from the much more perennially hot southern United States.
2021
The B.C. Coroners Service reported the summer's extreme heat led to the deaths of 595 people, 88 per cent of which occurred during the heat dome between June 25 and July 1.
Later, the B.C. Centre for Disease Control reported that statistical models showed that the province had 740 excess deaths in an eight-day period ending July 2.
Armel Castellan, warning preparedness meteorologist with Environment and Climate Change Canada, said the heat dome was a wake up call for British Columbians about how lethal heat can be.
2022
The heat dome killed 619 British Columbians, mostly vulnerable people, whose lives might have been saved through clear, co-ordinated communication and support.
It's time for us to stop kidding ourselves that events like the heat dome, the subsequent fall's catastrophic flooding in the Fraser Valley, and season after season of severe wildfires are isolated events nobody can anticipate. As Cox and Homer-Dixon put it, "The underlying trends and risks have been clear to specialists for years. And these same indicators now point to a future of near-constant, and steadily worsening, environmental, economic and social disruption."
2022
Last year's heat dome could have caused stress or even killed some of the birds, and the devastating floods could have washed out some of the spawning salmon eagles rely on as a food source. Meanwhile, a wave of avian flu has spread among wild and domestic birds across the province.
2023
E-Comm has been under scrutiny in recent years after it was overwhelmed during the 2021 heat dome, when more than 600 people died. And recently, a UBC student died in hospital a few days after calling 911 with an Apple watch after going into medical distress. E-Comm called back twice but didn't get through and did not dispatch first responders.
Images
