'The Pyrocene Is Well and Truly Here': Climate Crisis Made Eastern Canada's Fires 2 Times More Likely

The hot, dry conditions that fueled eastern Canada's unprecedented wildfire season were made at least two times more likely by the climate crisis, the latest study from World Weather Attribution has found.

The study, published Tuesday, also found that, by the end of July, Quebec's fire season was 50% more intense than it would have been without the human-generated release of greenhouse gas emissions.

"The Pyrocene is well and truly here, thanks to our continued burning of fossil fuels," study co-author and Imperial College London physicist Friederike Otto tweeted.

Canada's wildfire season has been the worst on the record books since late June, but the weather conditions that fueled it began the month before. The entire May to July period was the nation's warmest since 1940, according to World Weather Attribution (WWA). As of August 16, the Canadian government calculated that 5,753 fires had ignited to burn a total of 13.7 million hectares—that's 123% more fires and 602% more land burned than normal.

The fires have had a devastating impact on human communities, killing at least 17 people, damaging at least 200 buildings, and forcing more than 150,000 to flee their homes, WWA said in a statement.

"The wildfires had disproportionate impacts on Indigenous, fly-in, and other remote communities who were particularly vulnerable due to lack of services and barriers to response interventions," WWA wrote.

"Now we are able to put the number or an estimate on to what extent those conditions that we have seen this year are caused actually by climate change—and the numbers are very high."

The dangerous smoke from all this combustion has menaced the air quality in cities from Ottawa and Toronto to Washington, D.C. and New York City, where pollution neared a record June 7 with an air quality index of 341.

"The consequences from the wildfires reached far beyond the burned areas with displaced impacts due to air pollution threatening health, mobility, and economic activities of people across North America," WWA added.

For the study, the Canada-, U.K.- and Netherlands-based team looked specifically at the fires in eastern Canada, which were particularly abnormal and contributed the most to the smoke that drifted down over the U.S. East Coast and Midwest. They studied the daily severity rating, which defines how hard it is to put out a particular fire. To establish how extreme the season was at its peak, they also looked at the year's highest seven-day moving average of the fire weather index.

"Climate change made the cumulative severity of Quebec's 2023 fire season to the end of July around 50% more intense, and seasons of this severity at least seven times more likely to occur," the study authors concluded.

They also found that this peak fire weather was at least twice as likely and around 20% more intense.

Yan Boulanger, one of the study authors who works as a research scientist for Natural Resources Canada, told CBC News that the results were "shocking."

"We know that those extreme fire-prone weather conditions are occurring more frequently," he said. "Now we are able to put the number or an estimate on to what extent those conditions that we have seen this year are caused actually by climate change—and the numbers are very high."

The study authors also found that seasons like this one will only become more likely and intense if policymakers allow global temperatures to rise by 2°C above preindustrial levels.

"Until we stop burning fossil fuels, the number of wildfires will continue to increase, burning larger areas for longer periods of time," Otto toldThe Guardian.