2023-08-18 04:18:09
No respite since May. In Canada, firefighters have been fighting for several months against mega forest fires on an unprecedented scale. From east to west, the vegetation of several provinces is consumed by the flames which continue to progress. Nearly 168,000 people have had to be evacuated since the start of operations.
According to Canadian Interagency Forest Fire Center (CIFFC), as of August 16, more than 13.7 million hectares have gone up in smoke since the beginning of the year. A figure never reached: the previous record dated back to 1989, with 7.3 million hectares burned in the year. The firefighters are not yet at the end of their sentences, because a thousand homes are still active to date across the territory, and the fire season is not over.
Where did the forest fires start?
The first megafires started early in May, in the province of Alberta, in the west of the country. A month later, a massive blaze broke out in Nova Scotia to the east. Then it was British Columbia, in the northwest, which was hit hard at the start of the summer. Simultaneously to the east, record fires were observed in Quebec in July.
For the past few days, fires have been overwhelming the Northwest Territories. Authorities in the main city, Yellowknife, declared a state of emergency on Tuesday and ordered residents to evacuate by noon Friday. More than 230 fires are currently active in this province.
These fires were all the more noticed as the plumes of smoke spread to other countries. In the United States, New York was invaded for several days under a suffocating and thick orange and brown fog. Some smoke was even visible from Europe at the end of June, especially in the south of France.
What were they caused by?
Canada is used to wildfires, the season of which usually begins in May. But this year, the conditions were met for particularly intense situations. The country has been in a state of severe drought since the beginning of the year, with very little rainfall and particularly high temperatures.
“The vegetation is under water stress, that is to say in severe water shortage, explains Églantine Goux-Cottin, president and director of the ICEF (Consulting engineer in environment and forestry). It’s like a field of straw, at the slightest spark, it becomes a large blaze even more complicated to put out. This spark can be caused by human action (cigarette butt, campfire, malevolence, etc.) or by a meteorological factor such as lightning, which was the case in Canada.
The country, by its geographical location, is warming up faster than the rest of the planet. In recent years, it has been confronted with extreme weather events, the intensity and frequency of which are inexorably increased by climate change. This fire season is “the worst ever recorded”, however, warned the Canadian government.
Why are they difficult to control?
It is mainly the boreal forest, made up mainly of conifers, that goes up in smoke. The vegetation “burns there faster than that of temperate forests”, says Églantine Goux-Cottin. The unprecedented scale and multitude of fires, added to the fact that the affected areas are very isolated, forced the authorities to let the majority burn and to intervene only on the fires most threatening for the population and industries.
Especially since Canada suffers from a lack of manpower. Even if the firefighters are supported by the Canadian armed forces and international aid, this is not enough to stem all the disasters. Since May, nearly 5,000 firefighters from 12 countries have come to help, including South Africa, Australia, New Zealand and the United States. France had also sent a hundred firefighters and experts.
What is the impact on the environment?
The particularity of the boreal forest is that it is “the ecosystem that injects the most carbon dioxide when it burns”, indicates Églantine Goux-Cottin, which contributes strongly to global warming. According to data from the European Copernicus observatory published in early August, “total emissions from forest fires in Canada are around 290 megatonnes (of carbon), while the previous record, recorded in 2014, was 138 megatonnes”.
Canadian authorities have estimated carbon dioxide emissions at more than a billion tonnes, a record high. These figures are only provisional. The risk of fire should still be “above normal” until September, alerted Michael Norton, director general of the Canadian forest service.
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