Smoke from the wildfires engulfing the U.S. West and Canada and carrying harmful air pollution has triggered air quality alerts in the Upper Midwest and East Coast cities including New York, Philadelphia and Washington, D.C., on Wednesday, according to the National Weather Service.
The towering pyrocumulus clouds coming off these fires is lofting smoke all the way into the stratosphere, and the jet stream is carrying the smoke eastward across the country.
Our thought bubble: Due to the presence of small particulate matter, wildfire smoke can be hazardous to human health, even many, many miles downwind. The fires are also a source of carbon dioxide emissions, thereby acting to worsen global warming.
By the numbers: Smoke from the fires blanketed New York City sending its air quality index to an 170 before dropping to a still-unhealthy 158 on Tuesday — second only to the AQI of 174 in Krasnoyarks, Russia.
Boston, Massachusetts, and Hartford, Connecticut, also recorded unhealthy AQI readings that were higher than 150 on Tuesday.
Context: The wildfires, many of which started when a severe heat wave erupted in June, have been linked by scientists to human-caused climate change.
A haze over the Manhattan skyline on July 20. Photo: Spencer Platt/Getty ImagesSunlight interacting with wildfire smoke, causing the sun to appear with a reddish-orange tint in New York City on July 20. Photo: Lokman Vural Elibol/Anadolu Agency via Getty ImagesThe Statue of Liberty barely visible in the distance in New York City on July 20. Photo: Spencer Platt/Getty Images
Editor’s note: This story has been updated throughout.