Smoke from wildfires in the western United States and Canada spread nearly coast to coast, and from Canada to Mexico, on Tuesday, July 20, 2021, as seen in this map based on computer modeling output. (Credit: NOAA Global Systems Laboratory)
Yesterday, as my daughter sat in the stands of New York City’s Yankee Stadium, she turned her gaze from the players on the field to the sky. She was unsettled by what she saw: a miasma of air pollution.
“I’m at a Yankees game and the sky looks like Shanghai,” she texted me. “Is it from the fires?”
I was in Boulder, Colorado, where our own skies were filled with gunk and the air quality had declined to “UNHEALTHY FOR SENSITIVE GROUPS.” (That would include me, since I have asthma.)
So I checked satellite imagery, and sure enough, smoke from fires in the northwestern United States and Canada had been swept up by the jet stream and carried across the…