Human-caused climate change made the weather conditions that drove the season’s extreme wildfires in the Canadian province of Quebec between May and July at least two times more likely, according to a new attribution analysis by an international team of climate scientists as part of the World Weather Attribution (WWA) initiative.
The scientists also found that climate change, caused primarily by burning fossil fuels, made the fire-prone weather about 20 to 50% more intense.
The 2023 Canada wildfire season has been the most devastating ever recorded in the country, with nearly 15 million hectares already burned – an area larger than Greece – nearly double the previous 1989 record of 7.6 million hectares.
Smoke from the wildfires spread across Canada and the US with dangerous air quality leading to sharp increases in asthma-related emergency department visits and school closures. The high temperatures, combined with low humidity and the rapid disappearance of snow cover fueled the rapid spread of fires across Canada. In many regions of the world, hotter temperatures are drying vegetation, leading to more flammable conditions that increase the likelihood of wildfires both starting and spreading.
Scientists from the attribution team also calculated that climate change made the fire-prone weather conditions at least seven times as likely and 50% more intense. They commented that “although the fire-prone weather conditions were unprecedented, they are no longer extremely unusual”.
Dr Friederike Otto, senior lecturer in climate science at the Grantham Institute for Climate Change and the Environment, Imperial College London, said:
“Increasing temperatures are creating tinderbox-like conditions in forests in Canada and around the world. Until we stop burning fossil fuels, the number of wildfires will continue to increase, burning larger areas for longer periods of time.”
‘Unnatural disasters’
In the past few days, attention has shifted to British Columba and the Northwest Territories in the west of Canada, where over 30,000 households have been ordered to evacuate. Images of the wildfires in Kelowna and Yellowknife have shocked scientists and the public, with the huge range of over 400 wildfires raging. The town of Enterprise in the Northwest Territories has tragically been incinerated by the wildfires.
A state of emergency has also been declared in the province of British Columbia, with the premier of the province, David Eby writing on social media that:
“This year, we’re facing the worst #BCWildfire season ever. Over the past 24 hrs, the situation has evolved rapidly and we are in for an extremely challenging situation in the days ahead. Given these fast-moving conditions, we are declaring a provincial state of emergency.”
Distinguished professor Michael Mann, at the University of Pennsylvania, described the link between climate change and wildfires in a recent interview for Scripps News, commenting that, “It’s what many of us now call an ‘unnatural disaster’, it’s not a natural disaster … There are always a number of factors that come together, to produce these sorts of catastrophes, but one of those factors, undeniably, is human-caused climate change”.
This new WWA study is categorically not in reference to these British Columbia fires, but rather the wildfires from earlier in the year on the east coast. It is tempting to focus on the impact to the lives of humans and the loss of property and the economic impact. A more holistic approach would also focus on the tragic loss of animals, wildlife, plants, trees and insects, which will be catastrophic.
Canada now joins the growing list of countries drastically impacted by wildfires this year – alongside: Hawaii; Greece; Italy; Spain; Portugal; Ukraine and Türkiye.
The pollution dangers of wildfires
The WWA study focused heavily on the indirect impacts of the wildfires and especially that of air pollution. Tens of millions of people in the US received air quality alerts and were recommended to limit outdoor activities, as smoke from the wildfires drifted south.
The study states that:
“The impacts reached far beyond the areas affected by fires, with plumes of smoke blanketing large parts of Canada and the US. The most vulnerable people to the dangerous fine particles carried in wildfire smoke were those with underlying health conditions, reduced access to health services and living in low quality housing.
“The researchers say it is critical that the public should be more aware about the risks of dangerous air quality from wildfire smoke, particularly as fire weather risk increases due to human-caused climate change.”
The cause of the Canadian wildfires
With Reuters reporting “Most of the wildfires are believed to have been accidentally caused by human activity”, the temptation, for some, has been to reduce a complex situation to a simplistic solution: arson. However, this ignores the unusual lack of rain in May and early June in British Columbia and further ignores that “60% of wildfires are caused by lighting, while the remainder are due to human activity”.
Experts such as Robert Scheller, a professor of forestry and environmental resources at the NC State College of Natural Resources, argue that “Canada’s wildfires are being fueled by warmer-than-average temperatures and drought conditions”.
The WWA attribution study also deftly dealt with this issue of cause, by focusing on the conditions that are created that allow a fire to spread. Yan Boulanger, research scientist at Natural Resources Canada, said:
“The word ‘unprecedented’ doesn’t do justice to the severity of the wildfires in Canada this year. From a scientific perspective, the doubling of the previous burned area record is shocking. Climate change is greatly increasing the flammability of the fuel available for wildfires – this means that a single spark, regardless of its source, can rapidly turn into a blazing inferno.”
Government response
Canada’s prime minister, Justin Trudeau, declared that government support would be “unwavering” in this wildfire crisis:
“I brought the Incident Response Group together again today to address the wildfires in British Columbia and the Northwest Territories, and to make sure we’re continuing to mobilize all of the federal resources needed. Our commitment to supporting everyone affected is unwavering.”
Trudeau has also criticised Facebook’s news ban of the wildfires, which he felt was indicative of them putting ‘profits before people’. The premier has faced criticism in the past about the support of Big Oil by the Canadian government, but in mobilising the military to assist in the current evacuation of over 35,000 people and declaring support for communities, it is perhaps the wrong focus in the short-term. The pressing priority is to deal with the immediate threat and ensure that the threat to life is minimised.
A longer conversation about the role of the role and responsibility of the fossil fuel industry will now surely take place. The horrifying direct evidence is now all too clear for all to see – it’s no longer an ‘invisible’ threat that ‘only affects other people’, or ‘something for the scientists to worry about.’
CS Lewis once wrote that pain was God’s “megaphone to rouse a deaf world … it removes the veil; it plants the flag of truth”. The pain, suffering and devastating loss of life endured by those caught up in the wildfires may shift humanity out of its dreadful apathy in terms of climate action. On the other hand, we may have jumped directly over the newly named Anthropocene and entered a new world of the Pyrocene.







