Wildfire smoke is back – fires burning across Canada are already triggering US air quality alerts in the Midwest and Plains

(The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts.)

Charles O. Stanier, University of Iowa; Gregory Carmichael, University of Iowa, and Peter S. Thorne, University of Iowa

(THE CONVERSATION) Dozens of wildfires are burning across Canada in May 2024 and sending unhealthy smoke blowing into the northern U.S. again. At the same time, the southeastern U.S. is getting smoke from Mexico, where drought conditions have been fueling fires.

Last year, Canada’s record 2023 wildfire season introduced millions of Americans across the Midwest and northeastern states to the health hazards of wildfire smoke, with air quality alerts that reached levels never seen there before.

Professional baseball games were postponed and the skies in New York City turned orange with haze, at times exposing...