Drivers and Impacts of the Record-Breaking2023 Wildfire Season in Canada

The 2023 wildfire season in Canada was unprecedented in its scale andintensity, spanning from mid-April to late October and across much of theforested regions of Canada. Here, we summarize the main causes and impactsof this exceptional season. The record-breaking total area burned (~15 Mha)can be attributed to several environmental factors that converged early in theseason: early snowmelt, multiannual drought conditions in western Canada,and the rapid transition to drought in eastern Canada. Anthropogenic climatechange enabled sustained extreme fire weather conditions, as the meanMay–October temperature over Canada in 2023 was 2.2 °C warmer than the1991–2020 average. The impacts were profound with more than 200 com-munities evacuated, millions exposed to hazardous air quality from smoke,and unmatched demands on fire-fighting resources. The 2023 wildfire seasonin Canada not only set new records, but highlights the increasing challengesposed by wildfires in Canada.