By Thursday evening, more than 10 percent of Oregon’s 4.2 million residents were under an evacuation order, according to state estimates. Uncontained wildfires fueled by sustained global heating and extreme winds have burnt enormous swaths of land to a crisp, leaving the state’s air quality on par with some of the most prolifically polluted cities in the world. At the time of writing, up to 40,000 people have fled from their homes, joining tens of thousands of Washington and California residents threatened by historic wildfires in their states.