Heat Waves, Fires, and Smoky Air in Canada

“For those living through yet another horrific fire season this is a graphic reminder of how climate change is with us, not just intermittently, but all the time” says Premiere of BC, Horgan.

By Amy Smart of the Canadian Press, July 21, 2021


Photo credit Lucy

While raging fires illustrate the implications of climate change with dramatic visual impact, the flames themselves don’t tend to claim lives in Canada. It’s the heat that precedes and sustains them, and the smoke they billow far and wide, that can have widespread and devastating implications for human health. And then there is the ongoing stress of losing your home, or being evacuated or being on alert for evacuation.


Heat Waves are Increasing and Hotter Nights are Dangerous

When it comes to climate change, there is one fairly well-understood extreme that is already affecting humans around the world, most recently in Canada with deadly consequences-heat waves. According to a recent study published in the journal The Lancet, more than five million deaths annually around the world between 2000 and 2019 were associated with “non-optimal temperatures,” with roughly 10% or 500,000 of these deaths related to heat. While many of these deaths occur in tropical countries, heat waves are beginning to affect more northerly climes.

During the heat wave that suffocated B.C. at the end of June 2021, more than 800 people died in the province. For comparison, in the same period last year, there were 232 deaths, according to B.C. Coroners Service’s chief medical officer, Dr. Jatinder Baidwan. The coroner’s office is continuing to investigate all of the deaths in order to nail down exactly how many were heat-related.

While we know that daytime temperatures are rising, in some regions — specifically in parts of Ontario and Quebec — nighttime temperatures are warming faster. Those warmer nights mean our bodies don’t have any time to cool off. For people with health issues like heart disease or asthma, for example, this can be extremely problematic and potentially deadly. “Our bodies were not designed to put up with environmental heats that exceed the high 30s,” Baidwan said. “If you think about it, what happens to an air conditioning unit? When you stress it, it builds up with lots of ice on the outside and then it stops working. And in some ways that’s a great analogy for what happens to our bodies. With extreme heat, we just find it really hard to do the usual homeostatic sort of mechanisms and protocols that happen in our body.”

Parts of eastern Canada, including Ontario and Quebec, are seeing more frequent heat waves and tropical nights, defined as nighttime temperatures 20 C or higher. According to the Climate Atlas of Canada, the number of tropical nights in Toronto averaged roughly 6.9 annually from 1976 to 2005. With climate change, under a scenario where carbon emissions decline substantially, that is expected to climb to 17.6 annually from 2021 to 2050. If current rates of carbon emissions continue, the average number of tropical nights in Toronto is expected to hit 20.6 annually from 2021 to 2050. From 2051 to 2080, under the two different scenarios for emissions, the average number would rise to 26.4 and 42.8 respectively.

June 2021 was the hottest on record for the Northern Hemisphere. In fact, 2019, 2020 and 2021 are the three hottest Junes on record for the Northern Hemisphere.

Air Conditioning Creates Heat Islands in Cities

As Earth continues to warm, air conditioning may seem like a possible solution. The problem is that energy is needed to operate them, and this also produces heat. Cities create “heat islands” where heating is further amplified by  concrete structures, adding more stress to people who are living in a hotter climate. Some cities like  Toronto and Montreal are trying to introduce greener building codes and designs to address this. 

Widespread Effects of Heat on Wildlife

Average temperatures in Canada have already warmed by 1.7 C and the country is warming at more than twice the rate of the planet. Increasing heat waves with higher-than-average temperatures during days and nights are also taking a toll on animals and delicate ecosystems, as well as crops.

A study published in the journal Global Change biology last October found that nighttime temperatures are rising across most of the world. In those areas that saw more nighttime temperature warming than daytime, there was more cloud cover, higher precipitation and more humidity. This can affect nocturnal animals, but also animals that are active during the day who use the cooler nighttime temperatures to recover from heat stress. “The changes increase the boundaries at which nocturnal species can operate. So you may get shifts in ranges, which then messes up ecosystems from changing competition and changing predation/prey relationships, and things like that,” said Daniel Cox, lead author of the study and a research associate in the U.K. at the University of Exeter’s Environment and Sustainability Institute.

Nicole Mortillaro Senior Reporter, Science


Photo by Lucy

Forest Fires, Fire Weather and Climate Change

When forest fire researcher Mike Flannigan looks ahead at what climate change means for wildfires in Canada, he doesn’t beat around the bush: “in a word, the future is smoky.”

Flannigan has been studying fire for over thirty years. He’s researched the key ingredients of destructive wildfires – fuel, ignition, and weather – all over the world. His work, and the work of hundreds of other researchers, shows that climate change is predicted to worsen all three ingredients across most of Canada, making global warming a triple threat to our forests.

When he considers what’s in store for Canada, Flannigan says simply that “There is a lot more fire in the future, and we better get used to it.” More and more Canadians are living, working, and playing in Canada’s forests. That means more people are likely to be affected by larger and larger fires – even catastrophic ones. “Was Fort McMurray a one-off?” Flannigan muses: “Heavens, no.”

To figure out what climate change means for forest fires in Canada, Flannigan and a team of researchers at the Canadian Forest Service analyzed the findings of almost 50 international studies on climate change and fire risk. They found that our future looks “smoky” because climate change will worsen the three major factors that influence wildfire: having dry fuel to burn, frequent lightning strikes that start fires, and dry, windy weather that fans the flames.

Another recent study  by Flannigan and several other scientists predicts that western Canada will see a 50% increase in the number of dry, windy days that let fires start and spread, whereas eastern Canada will see an even more dramatic 200% to 300% increase in this kind of “fire weather.” Other studies predict that fires could burn twice as much average area per year in Canada by the end of the century as has burned in the recent past. 


There’s a vicious cycle connecting forest fires and climate change: warmer temperatures make fires more likely, and burning forests release greenhouse gas pollution that makes global warming worse. This means that overall efforts to reduce greenhouse gas emissions and slow global warming will also help prevent forest fires. And on the other hand, working to reduce the number and severity of forest fires will also help slow climate change.

Many aspects of wildfire are out of our control, but as Flannigan notes: “every human-caused fire is preventable.” And Findlater reports that many of the recent fires near Kelowna have been caused by human carelessness. A world of ever-increasing fire risks and consequences will demand more fire bans and forest closures as well as more innovative and life-long fire education to reduce the number of human-caused fires.

A recent fire set from a gender reveal party is possibly going to result in jail time.


How do we “get used to” a world with much more wildfire? Fortunately, there are a number of things individuals and municipalities can do to reduce fire risk. Fire Smart [https://www.firesmartcanada.ca ] guidelines are available for individuals and for community leaders. Municipalities can create and maintain fire buffers around and within their communities by bulldozing trees, removing built-up forest litter, and making creative use of parks and open spaces as fire breaks. Findlater would like to see provincial regulation of fuel-rich private land, requiring better management that will reduce fire risk to the community as a whole. And individual homeowners and businesses can design buildings with fire safety in mind, for example avoiding the use of flammable materials in construction and landscaping.

We also need to adapt our wildfire response strategies to a world of more frequent, more intense fires. Natural Resources Canada estimates the fire protection costs could double in Canada by 2040 as we attempt to keep up with the worsening risk.  Flannigan argues that remote fires should be allowed to run their course by burning freely without human interference. Concentrating fire-fighting budgets and capacity on wildfires that directly threaten human lives and livelihoods will prevent the most catastrophic impacts, naturally reduce the buildup of dry fuel in the wilderness, and prevent firefighting costs from growing wildly out of control along with our worsening forest fires.

Many effective and innovative firefighting strategies are already in place. Findlater suggests that excellent systems have been created to share emergency-response leadership and resources across regions, provinces, and the entire country. He notes that British Columbia’s regional emergency management services are getting better and better at coordinating their wildfire response: but “sad to say,” it’s because “we’ve had a lot of practice.”



One approach that can be effective in reining in intense wildfires is known as backburn – setting a controlled fire that backs into the prevailing wind in the path of an approaching wildfire. The low-intensity backburn consumes fuel in a managed way before a high-intensity, out-of-control fire gets the chance to burn it. “The fire goes out because there’s no fuel,” Dr. Flannigan said. But while the technique is effective, it can also be risky, particularly in mountainous regions such as Western Canada, where the wind direction can shift quickly and turn the backburn into a new out-of-control fire.

In anticipation of forest fire season, some jurisdictions will engage in prescribed burning, in which a patch of land is purposefully burned and the fire is monitored and controlled. This practice stems from the principle that an out-of-control wildfire that bumps up against land that has recently been subject to a prescribed burn will start to dwindle. Burned land is unlikely to burn again for 10 to 20 years.

Learning from Indigenous Fire Managers

“It may seem counterintuitive to fight fire with fire,” a report released last month by the Global Climate and Health Alliance says. “However, fire is used in carefully controlled ways by Indigenous communities around the world.”

The report, The Limits of Livability: The Emergency Threat of Smoke Impacts on Health from Forest Fires and Climate Change, recommended that wildfire agencies work with and learn from Indigenous fire managers.

One such Indigenous fire manager is Russell Myers Ross, the former chief of Yunesit’in First Nation, one of six communities within the Tsilhqot’in Nation in central B.C. Mr. Myers Ross is the community’s main liaison with Gathering Voices, an Indigenous-led charity that’s supporting a project aimed at revitalizing traditional fire management in the territory.

“Indigenous people have been using fire as a way of managing the land for hundreds, if not thousands, of years,” Mr. Myers Ross said. “For us, it’s a chance to revitalize that knowledge.”


Fighting B.C. Wildfires

Doug Findlater, mayor of West Kelowna, recalls seeing the 2003 Okanagan Mountain Park fire sweep into town: “It kind of looked like a war movie, with houses blowing up all over the place,” he says. More recently, Canadians watched with horror as the immense Fort McMurray fire of 2016 threatened the city. The Fort Mac fire caused the evacuation of almost 90,000 people and quickly became the most expensive natural disaster in Canadian history, destroying 2400 buildings and causing about $10 billion in damage.

Forest fires make headlines across Canada every summer. They regularly devastate millions of acres of forest  and sometimes threaten entire communities with sudden, catastrophic violence. Destructive fires have an enduring impact on the community that lingers long after people return home to resume their lives. Findlater speaks from experience when he says “life is never quite the same again after you’ve been evacuated.” The extraordinary danger and lasting impacts of wildfire explain why we spend so much money – about a billion dollars a year – fighting it. 

Fire is a seasonal summer threat because it can only start, intensify, and spread in hot, dry weather. Findlater reflects that “as a mayor, I don’t really look forward to summer in the way most people do.” He notes that as climate change brings on longer, drier summers, Canadians will have to live with more and more risk of more and more serious wildfires, and that we have to take decisive steps to manage the growing danger.

“Climate change is forcing B.C. to rethink how it fights wildfires, say experts. Tactics are adapting, but not fast enough as wildfires worsen. While the province has invested millions in fire prevention, some in the fire management sector say much more is needed, as well as a fundamental rethinking of fire suppression. The sudden incineration of homes in Lytton — with at least presumed two dead in the blaze, according to the  BC Coroners Service — came as a shock to one wildfire expert who previously advised groups in the area on prevention.

Photo by Lucy

“I was quite surprised to see how everything transpired there because I know how much work they’ve done in Lytton to clean up all the grass and needles, but they couldn’t tackle all the hazards around the community,” said Brenden Mercer, forestry management liaison for First Nations’ Emergency Services Society, who conducted assessments for Lytton-area First Nations and municipal authorities.

Last time we checked the province of B. C. has 277 active wildfires with about 5500 homes under evacuation orders and 17,691 properties on alert. Most fires have been started because of lightning. On average 60% of the fires are caused by lightning and 40% human cause either intentional, or accidental. Human-caused fires cause the most fires that affect homes, and are the major cause of fires in more remote areas, too. They include wildfires started by debris burning, sparks thrown from equipment and railroads, power lines, smoking, fireworks, campfires, accidental ignitions, and arson. Overall, human-caused fires have doubled the length of the wildfire season compared to lightning-caused fires.

“Generally speaking, B.C. was three weeks ahead of it’s drying cycle,” Cliff Chapman, director of regional operations for the B.C. Wildfire Service, told reporters Friday afternoon. “It is not really comparable to seasons of the past just because of the heat wave that set in in June.”

“Mercer, a registered forest technologist, said that much has improved in B.C. since the devastating wildfire season in 2017. In particular, the province has committed to working with First Nations, and there is funding for training Indigenous firefighters and preparedness. But he said more support is needed, in particular when it comes to prescribed burns which are carefully controlled blazes intentionally set to use up potential wildfire fuel. Such practices were widespread among Indigenous peoples in B.C. — but recent decades of fighting fires instead of preventively managing their fuel mean that many ecosystems have become a tinderbox. “It’s come to the point where some of these ecosystems have so much more fuel than they would have historically,” Mercer explained.”

“There is also more urban development encroaching on forests and climate change is also at play, contributing to the recent heat wave which saw records shattered across the province —  the highest in Lytton which reached 49.6C a day before it burned.”

“He urged authorities to follow First Nations’ advice and do “more aggressive prescribed burning,” especially around communities surrounded by grasslands mixed with pine needles. “Putting fire back into the landscape can help protect it from fire for almost a decade,” he said. “It’s 100 per cent the way the Indigenous people look at wildfires, compared to how governments fight wildfires. After the 2017 wildfires, the province’s emergency management agency increased its cooperation with First Nations. On Friday, Emergency Management B.C.’s Pader Brach said the province made efforts to ensure Indigenous communities were “sitting at the same table” as soon as possible this week, and that the government was taking a “collaborative” approach.”

“The Lytton fire can also serve as a wake-up call to prepare for the long-predicted impacts of climate change, said an expert at the University of Victoria. Wildfire management funding has been boosted to $101M as B.C. prepared for the dry season. “Climate impacts are driving these extreme fire seasons,” said Carly Phillips, with the Pacific Institute for Climate Solutions’ Wildfire and Carbon Project. “Unfortunately”, she said, “not only are wildfires worsened by climate change, but in turn, burning forests contributes massive amounts of carbon into the atmosphere, accelerating climate change itself.”

David P. Ball is a CBC News reporter in Vancouver. 


Here is another article on forest fire management if you would like to read more:

Prescribed Burns

From the link above: “Last month, a paper out of UBC selected a stand of old-growth forest outside Williams Lake, B.C. and used tree-ring data to carefully track what fires in the area used to look like before the onset of the 20th century. What researchers found was that, prior to the arrival of Europeans, prescribed burns through the area roughly every 10 to 30 years, and were usually of middling severity. Nowadays, modern fire suppression ensures that the same kind of forest will typically go 70 to 180 years without a burn, guaranteeing a much more severe fire when it does strike. “In absence of low- to moderate-severity fires, contemporary forests are dense with closed canopies that are vulnerable to high-severity fire,” wrote researchers. B.C. forests piled high with what wildfire experts call “fuel load” — the accumulated debris, deadwood and untreated clearcut areas that can dramatically accelerate the speed and intensity of a wildfire. There needs to be a great increase in the number of prescribed burns.


The Smoky Future and Our Health

“In an interview with The Globe and Mail, Prime Minister Justin Trudeau said the wildfires and deadly June heat wave that set more than 1,200 new temperature records across North America have provided the Liberal government with an opportunity to bolster its climate-change agenda. “We simply have to be even more aggressive in our thoughts,” he said. Already, wildfire seasons in some jurisdictions have become longer. In Alberta, for example, the fire season officially begins March 1 while just a few years ago, the start date was April 1.

The area burned by wildfires in Canada has doubled since the early1970s, said Mike Flannigan, research chair for predictive services, emergency management and fire science at Thompson Rivers University, in Kamloops. In California, where almost 10,000 wildfires raged during last year’s record season, that trend is even more pronounced. The area burned has increased by at least a factor of five.

Dr. Flannigan said it’s going to get worse – it’s just a matter of how much worse. Modest predictive modelling suggests the area burned in Canada will double again by the end of the century; more aggressive modelling predicts it will increase by a factor of as much as 11. And people who live far from the actual wildfires can be exposed to poor air quality from burning biomass. In 2018, smoke from wildfires in British Columbia spread across Canada and as far as Ireland; last year, smoke floated from the states of Washington and Oregon into Western Canada. Wildfires are about extremes. In Canada, 3 per cent of fires on average burn 97 per cent of the total area burned. 

The recipe for wildfire is always the same. It has three ingredients: ignition, either from human activity (which dominates in the spring) or lightning (which dominates in the summer); vegetation, which serves as the fuel; and hot, dry, windy weather. “If you have all three, away we go,” Dr. Flannigan said. “As the temperature increases, the ability of the atmosphere to suck moisture out of the vegetation increases almost exponentially.”

Scientists are still debating whether climate change is exacerbating the situation in ways beyond temperature, such as increasing the likelihood of the blocking pattern that held the hot, high-pressure air system over the West during the recent heat wave( heat dome). Dr. Flannigan said research in North America suggests that while this blocking pattern isn’t necessarily happening more frequently, it is increasing in intensity and duration. Another factor in the role of climate change is precipitation, which is harder to determine because of high variability of rainfall in the West.”

Photo credit Lucy

The Shocking Effects of the Smoke

“Whatever climate effects are lurking in the background, once a wildfire has started, its potential impact over a broad swath of the country in the form of smoke can be predicted with growing confidence. This is the goal of BlueSky Canada, a smoke-forecasting project led by atmospheric scientists at the University of British Columbia. On a daily basis, the BlueSky system takes in infrared satellite data that can spot where fires are burning, and combines them with data on fuels, soil moisture and wind patterns at altitude to estimate how much smoke is likely to be injected into the air and where that smoke is likely to find its way back to the surface.

Not every breath of smoke is created equal, because not all wildfire smoke is created equal. In addition to gases such as carbon dioxide, nitrogen oxides and volatile organic compounds, it’s also full of particulate matter – solid particles and liquid droplets of varying sizes. When it comes to smoke exposure, air quality indexes and studies tend to look at what’s known as PM2.5, The composition of the PM2.5 depends entirely on what, exactly, is in the line of fire. Grasses, trees, houses and cars, for instance, all release different substances into the air when burned.

“These particles are important because when you breathe them in, they’re small enough to get into your cardiovascular system,” said Chris Rodell, a BlueSky Canada researcher.

Dr. Henderson is so concerned about the health effects of smoke exposure that she helped develop a supplement to the classic Air Quality Health Index, which was originally developed for urban environments where the air pollution mixture is dominated by traffic-related and industrial pollution. The calculation includes PM2.5, but particulate matter is afforded relatively little weight. Practically speaking, this meant the classic index tended to underreport the health risk during fire season. The supplement to the classic index, known as AQHI-Plus, only looks at PM2.5 levels, better reflecting the air quality experienced during forest fire season. The AQHI-Plus is now in use in B.C., and Dr. Henderson said its use is also under consideration in other provinces and territories.

With high concentrations, visibility is greatly reduced and, as Dr. Henderson puts it, “You can smell the smoke and taste it.” But it’s at levels of just 30 micrograms or so per cubic metre that the population starts to respond adversely to the smoke. “When the smoke looks really bad, people think it is really bad,” she said. “But it becomes unhealthy long before it looks terrible.”

PM2.5 can reach deep into the lungs, prompting the body to mount an immunological response just as it would if it detected the presence of an unwanted bacteria or virus. “The immunological response ends up causing inflammation, and that inflammation is systemic,” says Dr. Henderson, who has been studying wildfire smoke for two decades and has published upward of 40 papers on the topic. In other words, particulate pollution from smoke can affect every organ system in the body.

So while people with asthma and chronic obstructive pulmonary disease are the canaries in the coal mine of wildfire smoke, the inflammation can also increase the likelihood of a cardiovascular event such as a heart attack or a stroke. Emerging research also suggests that the body’s response to smoke exposure can make it harder for people with diabetes to balance their insulin levels, and may affect brain function for those whose cognitive abilities are already compromised.

Also important when considering the effects of wildfire smoke is the duration of exposure. Smoke can be transient, lasting hours or days, or it can be persistent. Atmospheric conditions can park smoke over a particular area for weeks or even months, as was the case in Yellowknife in 2014. The “summer of smoke” in the Northwest Territories capital was one of the longest and most severe wildfire smoke exposures logged in the global evidence base” and resulted in a lot of hospitalizations and a great increase health issues seeking treatment.



For more reading about smoke from wildfires we came across this article in the Edmonton Journal on Tuesday July 27, 2021.

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