America has the world’s worst air quality again as smoke from the Canadian wildfires hits the Chicago area, with smog from the fires now reaching as far as Europe.
An air quality index reading recorded on Tuesday by the World Air Quality Index ranked Chicago as having the worst quality globally.
The city has been marked as having unhealthy air with a reading of 175 AQI, with parts of Michigan reaching higher.
The index is a measure of five common pollutants and runs on a scale from 0 to 500, with a rating over 150 considered ‘unhealthy.’
Advice given by Air Now, is urging people to stay indoors and reduce activity levels due to the toxic air outside.
It comes just three weeks after New York City was enveloped by the smoke, turning the sky an apocalyptic shade of orange and triggering numerous health warnings.
The city has been marked as having unhealthy air with a reading of 175 AQI, with parts of Michigan reaching higher
Haze obscures the Chicago skyline after smoke from wildfires in Canada blanketed the city
Cars sit at a red light on Michigan Avenue under a hazy Chicago sky earlier today
Chicago is now at the top of the worst air quality list, with Minneapolis and Detroit also now ranked in the top ten as of this afternoon
Video shared on social media on Tuesday shows downtown Chicago under smoke, with a thick haze visible around the area.
Mayor Brandon Johnson said: ‘This summer, cities across North America have seen unhealthy levels of air quality as a result of wildfire smoke, impacting over 20 million people from New York City, Washington DC, Montreal, and today here in Chicago.
‘As we work to respond to the immediate health concerns in our communities, this concerning episode demonstrates and underscores the harmful impact that the climate crisis is having on our residents, as well as people all over the world.’
Figures from the National Wildland Fire Situation Report in Canada shows that there are still 78 uncontrolled fires, with a further 122 being controlled and 83 being held.
Smoke from the blazes also crossed the Atlantic Ocean and reached western Europe earlier this week.
The smog that has made its way into Europe has done so via the jet stream – strong winds in the upper levels of the atmosphere.
This means the smoke will not lead to dramatically worse surface air quality like the Northeast US experienced a few weeks ago.
The Met Office said that the smoke would not have the same effect it had on the north east of the US as it is too high in the atmosphere
The UK Met Office said that while the smoke is high up in the atmosphere, it may make for some vivid sunrises and sunsets.
Earlier this month, the north east of the United States was covered in smoke from the fires which placed 100 million people under a air quality warning.
At the time, health experts warned breathing the fog can be as damaging as smoking 22 cigarettes a day.
Nanoparticles from the smog are so small they can penetrate the lungs and bloodstream, with side effects also including irritation to the eyes and throat as well as breathing problems.
People wear protective masks as the Roosevelt Island Tram crosses the East River after haze and smoke from the wildfires shrouded the Manhattan skyline earlier this month
The sun is seen behind the Empire State Building, One Vanderbilt and the Chrysler Building in New York City earlier this month
A sheet of smoke from the wildfires descended on New York leaving those in Manhattan unable to see the New Jersey skyline across the Hudson River.
As well as sending New Yorkers inside, air quality alerts were also introduced in states including Massachusetts, New Hampshire, Pennsylvania, Maryland, Illinois, Virginia and the Carolinas, according to the National Weather Service.
The conditions in Chicago are expected to continue overnight but should be slowly pushed south through and diminish according to the National Weather Service.