“Rising temperatures create powder keg-like conditions in forests around the world”

As of August 21, 2023, more than 1,000 fires were active across Canada, nearly two-thirds of which were deemed out of control by the Canadian Interagency Forest Fire Center (CINAC).CIFFC) In the space of a few months, more than 15.3 million hectares of forest became a smoke zone… five times the area of ​​Belgium! The disaster eclipsed the previous record set in 1989 at 7.6 million hectares. “The word ‘unprecedented’ does not do justice to the severity of the wildfires that have ravaged Canada this year.Yann Boulanger, a natural resource science researcher who co-authored the study published Tuesday, cautions. From a scientific point of view, the doubling of the previous record for burned area is simply incredible.“

However, according to the authors of this review, these fires are not as uncommon as one might think. “In the current climate, intense fire events like the one observed in May-July 2023 are a moderately intense event, expected to occur once every 20-25 years., they write, which has an annual probability of 4 to 5%. Researchers warn that percentage will continue to rise as the planet warms.

Canada on fire: “There are places where forest won’t regrow”

favorable conditions

“Canada experienced its warmest May-June period since 1940, breaking the previous record (0.8°C) set in 1998. Nationally, humidity was also the lowest”, note the authors of the study. Favorable weather conditions for fire spread were observed across the country from early May, and translated by the Forest-Meteor Index (IFM). This metric is calculated based on several factors (humidity, wind speed, precipitation, temperature) and is used to assess wildfire risk.

This indicator is also used by scientists to estimate the maximum intensity of fires by analyzing the maximum values ​​of the average IFM in a seven-day window. Data shows that these weather conditions are twice as likely and 20% more likely due to climate change. The scientists also concluded that climate change has increased the probability of fire-favorable weather conditions over the course of the season by a factor of at least seven, and that the 50% probability that they will become more severe.

Fires in Canada: “This wildfire is unprecedented in three respects”

Less ice, more fire

“Rising temperatures are creating powder keg-like conditions in forests across Canada and around the world. Until we stop burning fossil fuels, the number of wildfires will continue to increase, burning large areas for long periods of time.Friedrich Otto, a professor at the Grantham Institute for Climate Change and the Environment at Imperial College London, warns.

“In many parts of Canada, snow cover limits the onset and extent of the wildfire season: if a forest is covered with snow or wet from snowmelt, the risk of ignition and fire spread is low.”, Professor Philippe Cachon at the University of Quebec (Montreal) recalled for his role. “If snow continues to fall in a warming climate, wildfires will burn for several more days each year in Canada.

Vulnerable people

A real warning to many Canadians affected by the fires. Seventeen people died in the fire, while more than 150,000 people were evacuated and much infrastructure was damaged. “The current fire season is the most destructive on record. says Conrad Chau, President and CEO of the Canadian Red Cross.

The organization monitors the impact of climate change on an annual basis. “Ten years ago, the Canadian Red Cross’s response work was primarily overseas in support of large-scale disasters and emergencies. Today, most of the Canadian Red Cross is based in Canada..

Among the affected populations, the analysis showed that fires had a disproportionate impact on isolated tribal communities. “Particularly vulnerable due to lack of services and barriers to relief interventions”, Such as lack of access roads or air traffic. Its effects cross borders, with air pollution threatening people’s health, mobility, and economic activity across North America. Fire is also a source of major greenhouse gas emissions: according to the European observatory Copernicus, “Total emissions from wildfires in Canada About 290 megatons (carbon)The previous record was 138 megatonnes in 2014”.

In the colors of an orange disaster, New York suffocates under the toxic fumes of Canadian fires

“The challenges posed by this year’s wildfires and the projected increase in weather risks from wildfires raise important adaptation questions.”, researchers reiterate. “In the weeks and months after a fire, after-action reviews and adaptation discussions are essential.”

Last July, another global weather attribute analysis showed July heat waves in southern Europe and North America “Almost Impossible” Without climate change.