As the fire season in Canada heads deeper into uncharted territory, burning more land than in any year on record, it continues to generate excessive amounts of smoke, polluting the air in both Canada and the United States.
It is likely that smoke will continue its invasions, as Canada’s fire season is expected to run until at least September. But already, data sources make clear just how polluted the air has already been, and it’s bad news for public health.
A sea of Code Purple and Red
During May and June, 17 states from the northern Plains to the East Coast saw Code Purple conditions, according to Environmental Protection Agency data, signifying very unhealthy air on the Air Quality Index (AQI). Twelve more states observed Code Red conditions, the next-most-polluted level.
In Canada, six provinces observed Code Purple conditions, with five topping out at Code Maroon — the most polluted level.
Code Red or worse pollution is generally rare in most of the Lower 48, other than on the Fourth of July, when smoke from fireworks reduces air quality.
The two main incursions of smoke in the Eastern United States during June broke numerous records on the AQI scale:
- The Allentown area of eastern Pennsylvania saw its AQI reach 309 (Code Maroon), one of the highest daily averages for smoke pollution on record in the United States.
- New York City reached its highest AQI on record, 254 (Code Purple) in early June.
- Syracuse, N.Y., had never experienced Code Red levels before June 7, when it soared past Code Red range into Code Purple with an AQI of 233. The city saw four days reach at least Code Red during the month.
- Milwaukee, Indianapolis and Cleveland reached Code Red levels or worse on a record-high three days in late June, with AQIs as high as 245, 234 and 260, respectively — all in the Code Purple range.
Many other cities, including Washington, Buffalo, Chicago and Minneapolis, tested or bested records for smoke pollution.
Multiple outbreaks affected multiple regions
The first major smoke outbreak of the season came in mid-May, originating from fires in Alberta and British Columbia. The smoke pollution was extreme not only in those Canadian provinces but also in the northern and central Plains and Rockies in the United States.
As June began, new blazes erupted in eastern Canada, and they have been delivering smoke pollution ever since. Between June 6 and 9, unprecedented smoke pollution smothered the Northeast.
Another quick burst of smoke, primarily from fires in western Canada, moved into the Upper Midwest on June 14 and 15. It was the year’s most significant smoke event for much of Minnesota.
June closed with fires raging in Quebec and Ontario. The month’s second-to-last week featured the worst air of the year so far in northern New England. Then the smoke increased and headed south, becoming the year’s worst air quality event across the Great Lakes, the Ohio Valley and parts of the Mid-Atlantic and Southeast. That outbreak lingered in smaller amounts until about last Saturday.
An exceptional number of bad air days
From the northern Plains to the Mid-Atlantic, a huge area has encountered multiple days with bad air quality because of smoke pollution.
The states that have seen the most Code Red or worse days are Wisconsin, New York and Pennsylvania. Within this zone, a small area from north-central Pennsylvania to near Elmira. N.Y., saw six days with Code Red or worse air quality. So did a small sliver north of Watertown, N.Y.
New York City has seen four Code Red days, while Washington has seen three and Chicago two.
Bad-air days have been even more frequent in Canada. Despite fewer air-quality monitoring locations, a number of places have seen Code Red conditions on 10 or more days; one location near Grande Prairie in Alberta has logged 19 so far.
Among the largest cities in Canada, Edmonton has seen the most Code Red days with eight. In the east, Val d’Or, a city of about 20,000 nearer the fires in Quebec, has witnessed 11 Code Red days. Ottawa has seen six code reds, Windsor four and Calgary three.
The number of cumulative days with compromised air quality matters. Smoke pollution contains fine particulate matter, referred to as PM2.5, which is considered especially harmful because it can be inhaled through your lungs and enter the bloodstream. It can cause respiratory problems and, in more severe cases, heart attacks, decreased lung function and even premature death, according to the EPA.
A study published last year found air pollution is worse for global life span than cigarettes or alcohol.