OTTAWA: Scientists blame climate change for Canada’s record-breaking wildfires this year after months of hot, dry weather produced debris-like conditions.
The same has been supported by a recently released comprehensive scientific analysis which found that combustion of fossil fuels by humans increases the likelihood of a fire season of this severity by at least seven times.
According to research by the World Weather Attribution Group, global warming increased the likelihood of wildfires by 50 percent.
“As we continue to warm the planet, these kinds of events will become more frequent and more intense,” first author Clair Barnes, an environmental statistician at Imperial College London, told a news agency.
Canada is experiencing the most destructive fire season on record due to record-high temperatures, low humidity and early snowmelt. Nearly 15.3 million hectares (37.8 million acres) burned: an area larger than Greece and more than double the previous record set in 1989.
About 200,000 people have been evacuated, at least four have died, and smoke from the burning forests has led to dangerous air pollution spreading across much of Canada and the United States to the south — spikes in emergency room visits and even school closings.
According to recent research, wildfires in late July directly released more than a billion tons of carbon dioxide into the atmosphere, as well as methane and nitrous oxide, which had a combined greenhouse effect equivalent to another 110 million tons of carbon dioxide. .
For this study, the researchers examined the eastern province of Quebec and focused on zones that are similar in climate and vegetation. The region saw an unusually high number of fires in May and June, when national temperature records were broken by 0.8 degrees Celsius (1.4 degrees Fahrenheit).
Because fires are very complex and not driven by climate alone, researchers instead focused on the conditions leading to fires using a metric called the Fire Weather Index (FWI).
This combines temperature, wind speed, humidity and precipitation. The team collected this data from January to July to derive a degree of fire weather severity throughout the season.
While the fires in Quebec were unprecedented, an analysis of the recent climate record indicated that the seasonal conditions causing the fires are no longer rare, occurring once every 25 years. This means they now have a four percent chance of occurring each year.
To understand the contribution of human-caused global warming, they used computer model simulations to compare today’s climate, after about 1.2 °C (2.2 °F) of global warming since the late 19th century, with the climate of the past.
This showed that due to climate change, such severe periods are at least seven times more likely to occur compared to pre-industrial times. However, Barnes emphasized that this is a lower estimate, with the researchers choosing to be conservative in the face of statistical uncertainty. Yan Boulanger, an ecologist with the Canadian Forest Service and second author of the report, told AFP the cumulative impact of fire-friendly circumstances was key. “It’s because those fire weather conditions lasted so long that those fires could get so big.”
The team also identified a seven-day stretch when fire weather conditions were at their peak and found that such peak conditions are more than twice as likely to occur in the past as a result of climate change.
If the world continues to burn fossil fuels at high rates, the likelihood and intensity of severe fire weather conditions will only increase, the analysis showed.
These fires threaten the future of the forestry sector, Boulanger warned, questioning whether regeneration efforts can keep up with the losses.
So far, the hardest-hit communities are remote and have relatively few resources, including indigenous people who made up 75 percent of those evacuated in July.
“This increasing severity of extreme events and the likelihood of extreme events will not stop until we reach net zero and stop adding more greenhouse gases to the atmosphere,” Barnes said, adding that it is “not too late” to lobby political leaders to change course. .
World Weather Attribution is an international collaboration that has now completed more than 50 studies of extreme weather events, with the results subsequently reviewed in peer-reviewed journals.
