This extreme and widespread pollution event, caused by dozens of out-of-control wildfires burning in northern Minnesota and adjacent portions of Ontario, has brought the worst air quality on record to much of the Great Lakes, mid-Atlantic, and Northeast United States. The fires have resulted in hazardous pollution levels, with 50 official EPA monitors recording a 24-hour AQI in the "Hazardous" range, and hundreds and perhaps thousands of premature deaths. The significance of this event lies in its direct link to climate change, which has increased fire danger by up to five times. The heat that fueled these fires would have been "highly unlikely" to have occurred in a world without climate change. Rising temperatures have ushered in an era of hotter and drier weather, lending the right conditions for wildfires to erupt. The Canadian boreal forest, covering 550 million hectares, is dependent on fire for much of its ecology, but climate change has increased fire frequency and intensity. This devastating event highlights the need for urgent action to address climate change and its impacts on air quality and human health. The long-range fire assessment calls for above-average fire risk over much of the forested areas of northern Canada and the western U.S. this summer, and frequent bouts of poor air quality from wildfire smoke across much of North America. The fact that many indigenous communities, who have traditionally managed these boreal forests effectively, are now facing mega-fires due to climate change underscores the need for a more nuanced approach to forest management. The implications of this event extend beyond North America, with potential impacts on global air quality and human health. As the frequency and magnitude of extreme wildfires around the globe have doubled in the past 21 years because of climate change, it is essential that we take immediate action to reduce greenhouse gas emissions and transition to a more sustainable future.