The US Capitol building is enveloped in smoke as wildfires burn throughout Canada (Picture: Reuters / Getty)
More than one third of the population of the United States is under air quality alerts due to smoke from the ongoing Canadian wildfires.
Approximately 120million people in the Midwest and East Coast are experiencing unhealthy air quality, from Minnesota to Virginia, the US Department of Environmental Protection said.
The smoke is coming from a series of severe wildfires that have been burning across Canada. Over 200 fires are currently burning in every single Canadian province,
The fires have burned about 30,000 square miles of wilderness – an area roughly the size of South Carolina.
Air pollution is measured by the air quality index (AQI), which determines the average amount of fine particulate matter (PM2.5) in the atmosphere.
AQI ratings between 101 and 150 are considered unhealthy for sensitive groups, such as people suffering from heart or breathing. An AQI above 150 is considered unhealthy for all people.
An AQI of over 300 is considered actively hazardous and likely to effect a region’s entire population.
As of Thursday afternoon, Washington, DC had an AQI of 176, making it the second most polluted city in the world.
Chicago reported some of the worst air pollution in the world over the last week from the wildfire smoke (Picture: KAMIL KRZACZYNSKI/AFP via Getty Images)
On Wednesday, the Metropolitan Washington Council of Governments issued a ‘code red’ warning for the nation’s capital, warning all citizens to avoid long exposure to the air.
The warning extended through Thursday, but will be lifted to a ‘code orange’ on Friday.
‘Air quality in the DC region is expected to improve tomorrow although it will still be unhealthy for sensitive groups,’ the local government said.
Photos from DC show the city’s many monuments and landmarks enveloped in thick plumes of smoke, including the White House and the Capitol Building.
Downtown Chicago is obscured by haze from the Canadian wildfires (Picture: AP)
Smoke from the wildfires completely envelops Pittsburgh’s skyline (Picture: AP)
The city with the worst air quality on Thursday was Detroit, Michigan, where the AQI peaked at 202 and was rated ‘very unhealthy.’
Earlier in the week, Chicago, Illinois reported the worst air quality in the world as the index rose above 150.
Some sensors in Pittsburgh and other parts of western Pennsylvania were detecting an AQI as high as 237.
Officials in New York also warned citizens to take caution.
New York City was covered in an orange smog from the wildfire smoke earlier this month (Picture: REUTERS)
‘Air quality is unhealthy in every corner of the state of New York,’ Governor Kathy Hochul said at a news conference.
Western, central, and northern New York were all placed under air quality warnings. The city of Buffalo saw a high AQI of 159 on Thursday.
New York City Mayor Eric Adams also warned New Yorkers to take precautions on Thursday, and advised citizens to wear masks and avoid exercising outside.
The city and other parts of the Hudson Valley and Long Island reported ‘moderate’ AQI numbers, much lower than when a thick orange cloud of smog enveloped the city three weeks ago.
Governor Hochul said there was ‘no end in sight’ for the Empire State. ‘This is our new reality,’ the governor said.
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Photos from DC show the city’s many monuments and landmarks enveloped in thick plumes of smoke, including the White House and the Capitol Building.