Major cities on the eastern seaboard of the US appeared to be through the worst of the dense smoke that drifted from wildfires in Canada, but air quality remains hazardous and daily life is still disrupted.
New York City, Washington DC and Philadelphia all recorded their worst air quality in years this week as flights were grounded, baseball games postponed, and outdoor events cancelled.
Local officials across the east coast urged residents to stay indoors or to wear masks if they ventured outside.
President Biden, who offered assistance to the Canadian prime minister, Justin Trudeau, said the fires were “another stark reminder of the impacts of climate change”.
Poor air quality peaked on Thursday along much of the east coast, according to the Environmental
