What they found: In just five months, Canada emitted enough carbon from wildfires in 2023 — 647 million metric tons — to be comparable to the annual fossil fuel emissions from the top 10 largest emitters. The wildfire-related emissions were more than four times larger than Canada's annual fossil fuel emissions.

The blazes produced more planet-warming carbon than almost any country, researchers found. That could upend key calculations on the pace of global warming.

Wildfires that swept Canada's woodlands last year released more greenhouse gases than some of the largest emitting countries, a study found on Wednesday, calling into question national emissions budgets that rely on forests to be carbon stores.