Scientists at the World Resources Institute and the University of Maryland calculated how devastating the impacts of the months-long fires in Canada in 2023 that sullied the air around large parts of the globe. They figured it put 3.28 billion tons (2.98 billion metric tons) of heat-trapping carbon dioxide into the air, according to a study update (not peer-reviewed, though the original study was). 

“The loss of that much forest is a very big deal, and very worrisome,” says Jacob Bendix, professor emeritus of geography and the environment (who wasn’t part of the study).

“Although the forest will eventually grow back and sequester carbon in doing so, that is a process that will take decades at a minimum, so that there is a quite substantial lag between addition of atmospheric carbon due to wildfire and the eventual removal of at least some of it by the regrowing forest. So, over the course of those decades, the net impact of the fires is a contribution to climate warming,” he says.

Read more in the Associated Press article, “Canada’s 2023 wildfires burned huge chunks of forest, spewing far more heat-trapping gas than planes.”