Analysis | Why Canada's wildfires are extreme and getting worse, in 4 charts - The Washington Post

Why Canada’s wildfires are extreme and getting worse, in 4 charts - The Washington Post

There is little that’s normal about the siege of Canadian wildfires that sent record amounts of smoke pouring into the Lower 48 last week. Even as the fires in Quebec have eased some and the hazy skies over the eastern United States have mostly cleared, blazes still rage in parts of British Columbia and Alberta.

Statistics on the fires — which help place their scope in historical context — continue to show how extreme they are. And they’re part of a trend toward larger, fiercer fires and more-damaging fire seasons.

The fires have burned the most land on record so early in the season — more than 4.7 million hectares(11.6 million acres). And already, even though the fire season is just underway, more area has burned than in all but three entire fire seasons since modern records began in 1983.

The fire season’s rapid start can be traced to an outbreak of lightning-triggered blazes unrelenting heat and parched ground.

Then Nova Scotia saw its biggest fire on record, and along came the blazes in Quebec, which were also mainly triggered by lightning. Residents of the eastern United States felt their smoky effects firsthand.

Several other key statistics drive home how unusual this fire season has been and how it fits into a concerning trend toward larger Canadian fires.

Record fire emissions so early in the year

The chart above, which shows the amount of carbon released into the atmosphere by the fires this year, demonstrates just how far ahead this season’s activity is compared with recent history.

It’s quite consistent with the fact that 4.7 million hectares have burned compared with the June 11 average of about 310,000 hectares, according to the Canadian Interagency Forest Fire Center.

The area burned is already more than double the annual average of 2.1 million hectares. On average, only 15 percent of the seasonal total is usually burned by now. Although fire is common in May in parts of Canada, the majority of burning historically comes in July, August and September in most years.

The only three seasons that had more hectares burned in total than this year so far are: 1994 (5.3 million hectares), 1989 (5.9 million hectares) and 1995 (7.1 million hectares).

If this season continued to burn land at is current pace, while improbable, the year-end total would be about 32 million hectares, or 4.5 times more than the current record holder.

The land area burned so far has exceeded 5,000% of normal in some provinces

While Canada has had large fires in the past this early in the year, rarely has so much land area burned. Nova Scotia, Quebec, British Columbia, Alberta and Saskatchewan have been hit especially hard.

Fires have already scorched 25,201 hectares in Nova Scotia, nearly 10 times as much as in the entire season in 2008, the previous top year. The amount of land burned so far is 4,000 percent of the average amount.

It’s a similar story as one heads westward.

The 1,018,713 hectares burned in Quebec so far is greater than in every entire season on record except 2013.

In British Columbia, Alberta, Saskatchewan and the Northwest Territories, where large fires are more common, the early-season burning has also been exceptional. The land area burned in British Columbia, for example, is about 5,000 percent of the normal to date, with 653,877 hectares charred.

Fires that simmered down briefly in cooler and damper conditions in central and western Canada have roared back to life in recent days as a new heat dome has developed. One town, Edson, Alberta, was evacuated Friday for the second time in a little more than a month.

Fires are trending bigger

On social media, some have tried to dismiss this year’s fire activity by pointing to a trend toward fewer fires in Canada. There is indeed a downward trend.

Over the past 20 years, there have been more than 2,000 fewer fires per year in Canada compared with the first 20 years in the modern record. Although Canada’s wildfire-fighting abilities lag those in the United States, the decrease observed is probably an indicator of improved prevention.

But while the number of fires is decreasing, the average size of any given fire has substantially increased.

From 1982 to 1993, Canada’s median wildfire size was 112 hectares. From 2013 to 2022, it was 509 hectares. This year so far, it’s about 1,900 hectares.

Angrier wildfires are expected in a warming world, especially in the northern latitudes, where warming is happening fastest. Larger fires are hotter and thus more intense, allowing for rapid increase in size, which sends more smoke higher into the atmosphere and farther downwind.

The smoke episode just seen in the United States was a generational event, but such episodes will probably become more common in the future.

More acres are burning in a typical fire season

The land area burned can vary considerably from year to year, as it has done in recent decades. But a typical year is seeing more land burn on balance.

From 1983 to 1992, the median season saw less than 1 million hectares go up in flames. That value ticked up nearly twofold in the next 10-year period.

After briefly leveling off, the average area burned in a median season grew to 2.8 million hectares for 2013-2022. Every year in the past decade has seen was 1.4 million hectares of land or more charred, except 2020.

This increase fits in with recent trends toward rising temperatures in Canada. According to Environment Canada, average temperatures have risen in every season.

With the potential for more heat waves in coming weeks and months, the deck is stacked for the biggest fire season in recent history in Canada. The main question may be how much distance it puts between it and the soon-to-be-second-place year.