In the western United States, air quality alerts remain in effect for huge swaths of California, Oregon and Washington, as thick smoke from record-shattering wildfires continues to bring some of the world’s worst air pollution to millions of people. Forecasters are hoping cooler temperatures and calmer winds will help firefighters get the upper hand on containing the blazes. Over 5 million acres have burned, and at least 35 people have been killed by fires fueled by the climate crisis.