After a summer of record-breaking temperatures and raging wildfires, Canadians should be prepared for more scorching heat waves in the years to come, experts have warned.
The extreme weather events — attributed to climate change — that the country saw this past summer should serve as a “warning sign” that urgent climate action is needed, said Kent Moore, professor of physics at the University of Toronto, Mississauga.
“If we continue to warm the planet up, we’re going to see more and more of these events. They’re going to become more and more catastrophic,” he told Global News.
So, what does this mean for next summer? It’s hard to clearly predict, experts say, as there are many variables at play.
According to the latest report by the Intergovernmental Panel on Climate Change (IPCC), global surface temperature will continue to increase until at least the mid-century under all greenhouse emissions scenarios.
Global warming of 1.5 degrees Celsius and 2 degrees Celsius will be exceeded during the 21st century unless deep reductions in carbon dioxide (CO2) and other greenhouse gas emissions occur in the coming decades, the UN climate panel said in its report published in August.
A “heat dome,” which is a high-pressure system that traps warm air underneath it, raised the mercury to unprecedented levels in Canada, shattering more than 100 heat records across British Columbia, Alberta, Yukon and Northwest Territories this year.
Looking at the summer surface temperature trends, Peter Carter, an expert reviewer for the IPCC, is concerned that Canada like the rest of the world is headed for “hellishly hot summers.”
According to Carter, summer surface heating is a crucial indicator as it drives increasing heat waves, drought and forest wildfires. This year, global surface heating reached 1.15 C, NASA data showed.
“I’m afraid until governments decide to … put the global emissions into immediate, rapid and large-scale decline … we are inevitably going to get more worse extreme weather events,” he told Global News.
Because Canada is located in the polar region, which has warmed about twice as fast as the global average, it is heating up quicker than most other nations on the planet.
That’s largely because of how the greenhouse effect works, explained Steve Easterbrook, director of the School of Environment at the University of Toronto.
“It traps outgoing heat within the Earth’s atmosphere and … it’s at the poles where the Earth loses the most energy,” he told Global News.
Climate change models show that global warming is irreversible in the sense that the planet cannot be cooled down, but further warming can be stopped by halting greenhouse gas emissions, said Easterbrook.
Like Carter, Easterbrook is convinced Canada is in for more dangerously hot summers.
“I can reasonably confidently say within the next decade, there will almost certainly be a summer hotter than this one for Canada,” he said.
“And then the longer the warming goes on, the more of those hot years we’ll see.”
Looking ahead to 2022
On top of global warming, opposing climate patterns El Niño and La Niña may determine the severity of the next summer season.
During El Niño years, trade winds weaken and the Pacific Ocean tends to release more heat into the atmosphere, making areas in the northern U.S. and Canada drier and warmer than usual.
During La Niña years, trade winds are stronger and water temperatures become cooler-than-average in the eastern Pacific Ocean near the equator. Hence, Northern U.S. and Canada tend to be wetter and colder.
Episodes of El Niño and La Niña typically last nine to 12 months. And while they occur every two to seven years, on average, they don’t have a regular schedule, according to the National Ocean Service.
Also, La Niña is less common than its sibling, El Niño.
When neither climate pattern is present, the El Niño-Southern Oscillation (ENSO) cycle is neutral and does not influence airflow.
“We are potentially entering another weak La Niña,” said Anthony Farnell, Global News’s chief meteorologist, adding this could “put a damper on the warming going on around the planet in 2022”.
For Moore, he says it’s unlikely Canada will see another extreme summer next year.
“We typically don’t get extreme events one after the other because they are quite rare,” he said.
To better prepare for next year, Easterbrook said more accurate weather forecasting a month or two in advance would be helpful.
Planting more trees can also help provide shade and have a cooling effect on the environment, he added.
“We certainly need to make our towns and cities more climate resilient when it comes to heat.”