Record-setting wildfires in Canada could continue burning at an abnormally high rate for several more weeks, though the spread of blazes is likely to start diminishing in September, according to federal projections released on Friday.

Forest fires have engulfed parts of nearly all 13 Canadian provinces and territories this year, forcing home evacuations, disrupting energy production, and drawing in federal as well as international firefighting resources. Four firefighters have been killed in the line of duty.

So far about 134,000 square kilometers (52,000 square miles) of land have been scorched, more than six times a 10-year average, and nearly 168,000 people have been forced to evacuate at some point this season.

"This summer has turned into a challenging marathon," Canadian Forest Service official Michael Norton told a media briefing on Friday.

"Our most recent projections indicate the potential for higher-than-normal fire activity remains across much of Canada in August and September," Norton said.

Norton said the simultaneous flaring up of blazes across the country was "virtually unheard of" and largely due to drought conditions that continue to intensify in some areas and will contribute to ongoing fire activity through late summer.

"In September, we anticipate that the potential area at extreme risk will become a bit smaller ... [however], large existing fires will continue burning or smoldering and new problematic fires can occur anywhere."

The fires also have sent plumes of smoke across Canadian and U.S. skies, raising health alarms and concerning scientists about the impact on the atmosphere.

The EU's Copernicus Atmospheric Monitoring Service estimated last week that Canadian wildfires have released 290 million metric tons of carbon, more than 25% of the global total for 2023 to date, and emissions are set to rise as hundreds of flames rage on. (Reuters)

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