Canada Wildfires Are Still Burning—Why and When Will it End?

Canada is already on track to have its worst season for wildfires, with over 20 million acres of forest burned, as a mix of hot and dry conditions is having devastating consequences for wildlife and poses increasing health risks for people in the path of smoke clouds.

The latest official maps as of Friday show the most intense wildfires in Canada are focused in Quebec and western Ontario, as well as in Alberta province, which borders Montana.

In the past day, the danger has also become "extreme" in northern parts of Saskatchewan and British Columbia.

As of June 29, figures from the Canadian Interagency Forest Fire Centre (CIFFC) show that there were 497 active fires, or which 229—nearly half—were out of control. In the year to date, 8.1 million hectares (about 20 million acres) of land have been burned.

Cities in northeastern U.S. states have been impacted by plumes of smoke descending on southerly winds, reducing visibility and causing the U.S. government to issue alerts for some places.

What Caused Canada's Wildfires?

What makes 2023's wildfire season so remarkable is that the area burned already this year has exceeded the previous record set in 1995, when 7.1 million hectares (17.5 million acres) of land were burned across the entire year.

Canada's wildfire season typically runs from May to October, suggesting the situation could grow worse as 2023 progresses. Meanwhile, NASA said earlier this week that smoke clouds had already made it as far as western Europe.

In recent weeks, northern continental America has seen warm, dry weather with little rain, after a relatively dry winter.

"You have a lot of heat and dryness at this moment in time, which means there's a lot of potential fuel," Mark Maslin, a professor of earth system sciences at University College London (UCL), told Newsweek.

"The other thing is that the forests aren't managed, and therefore all of that fuel—i.e. the dead wood, et cetera—isn't cleared, just because [the forests are] massive," he said. "And so what you have is a stockpile of fuel which can be ignited very easily."

Experts largely agree that the widespread forest blazes, and the conditions that have allowed for them, are another example of extreme weather caused by climate change.

"Extreme weather is the by far the dominant cause of this record-breaking fire season currently occurring in Canada," Apostolos Voulgarakis, a professor of climate change at Imperial College London and AXA chair in wildfires at the Technical University of Crete, told Newsweek.

"Summers with more intense droughts and heat than average have always existed, but the key for explaining what is happening right now is that these naturally occurring phenomena are pushed to new extremes due to climate change, which is causing more and more destructive phenomena around the world as it unfolds."

As the average temperature of the earth warms, more energy is being pushed into the weather system, contributing to greater volatility in the jet stream—a current of air that divides colder atmospheric patterns toward the poles from warmer climes near the tropics.

This makes it shift further northward and southward than usual, precipitating freak hot weather events in area closer to the poles than historically expected, such as 2022's heatwaves in Europe, and cold snaps further towards the equator, such as the winter freeze as far as Texas in December.

"Quite a lot of these [wildfires] are burning quite a long way from where you would expect a strong local, human influence—so there clearly is a role of climate change coming into this," Chris Brierley, an associate professor of climate science at UCL, told Newsweek.

There are concerns that humans may, inadvertently, be lighting the touchpaper on such arid conditions. At the end of May, Nova Scotia's Premier Tim Houston warned residents not to flick cigarette butts due to the risk of combustion.

Maslin said that even something as seemingly insignificant as a broken glass bottle could "concentrate sunlight and cause a spark."

Why Are They Still Burning?

Official figures show that the number of wildfires across Canada picked up rapidly from the end of April, and the weekly totals have been increasing since then. In the year to date, there have so far been 3,053 wildfires.

"The problem is that, once the fires start, because it's so dry and hot, there's nothing preventing them from becoming wildfires and burning vast areas of forest," Maslin explained.

The climate author added that while trees with deep roots would be able to draw water from deep underground, a dry underlayer to the forest was "like a keg of gunpowder just waiting to go off."

Air quality was expected to improve on Thursday as a weather front moved into northern Quebec, with hopes that heavy rain would damp down the wildfires and bolster firefighting efforts.

However, Steven Flisfeder, a meteorologist at Canada's Environment and Climate Change department, told reporters on Wednesday that the heaviest rain was expected to miss the worst-affected areas, according to the Toronto Star.

The latest forecast for the region by Environment Canada says that there will be patches of cloud on Friday, with chances of showers on Saturday. A long-range forecast by Weather25 suggests a more consistent stretch of rain could arrive in the second week of July.

When Will Canadian Wildfires End?

Firefighting efforts alone are unlikely to quell the blazes.

Bringing the current swath of wildfires to a halt depends not merely on there being rain, but consistent or heavy rain over an extended period.

"Given how much energy these fires have while they burn, it is pretty much impossible for them to stop unless large swaths of heavy rains come their way," Voulgarakis said. "That is not predicted at the stage we are now, but we are hoping for the best."

This is because wildfires can only be prevented by stopping the two main conditions that lead to them starting—dry fuel and hot conditions that make ignition more likely.

"They will end once there is enough precipitation to dampen the actual ground enough that the fires can't either spread or catch in the first place," Maslin said, adding: "When the temperature's also lower, you find that less combustion actually occurs."

When that will be is hard to say, but there will have to be enough rain to soak the dry ground and dead wood that is allowing the blazes to spread so rapidly, which has the added effect of preventing combustion events in the first place.

Smoke or Heat: Summer 2023 for Many

Earlier in the week, Cleveland, Ohio, became so engulfed in smoke that the city's skyline disappeared while New York has been subject to an orange haze.

Air particle pollution is as of Friday considered at unhealthy levels in parts of Washington D.C., Pittsburgh and Baltimore, as well as many other areas on the East Coast and in the Great Lakes regions, according to government air quality monitoring site AirNow.

At present levels, it recommends residents avoid strenuous outdoor activities, shorten the amount of time they have to spend outside or wait for the air quality to improve before exercising in the open.

"The biggest problem with wildfires apart from the immediate danger is the decrease in air quality," Maslin said. "This is very severe because the soot and smoke can cause huge issues [for] people with sensitive respiratory diseases."

As well as potentially exacerbating conditions such as asthma, the particulates from the wildfires can compound pollution already produced by humans.

According to Advisory Board, a healthcare research firm, experts have warned that exposure to the smog can be as damaging to the lungs as smoking 22 cigarettes a day. Maslin likened the effects to that of a city with bad air quality "multiplied multiple times."

At the same time as the Northeast and Midwest is facing a haze of smoke, meteorologists have issued excessive heat warnings for swaths of the U.S. Southwest caused by a heatwave that is expected to continue into next week, with temperatures sustained above 100 degrees Fahrenheit.

On Thursday, the National Weather Service said the heatwave is expected to ease somewhat early next week, before conditions return to "typical summertime heat" towards the latter half of the week.

However, it noted that heat-related dangers to people remain elevated "due to the longevity of this ongoing heatwave."

Meteorologists at the National Oceanic and Atmospheric Administration have said that the same static weather pattern causing the unusually hot, dry conditions in Canada had then caused both the smoky air descending over northern America and the oppressive heat in the south.

"Pick your poison," Greg Carbin, forecast operations chief for the agency's Weather Prediction Center, told WRAL on Thursday, adding: "As long as there's something to burn, there will be smoke we have to deal with."

"High air pollution levels combined with intense summer heat lead to amplifying effects when it comes to the wellbeing of the population, with the risk for serious health problems and hospitalizations increasing sharply," Voulgarakis said. "This demonstrates the compound disasters that can emerge with climate change."

Update 07/03/23, 4:57 a.m. ET: This article was updated to include comments from Apostolos Voulgarakis.