Summer of smoke among the worst on record for Alberta's biggest cities

Smoke drifting through an open window. Haze so thick the street lamps glow hours before dusk.

Air pollution from wildfires has become an unwelcome part of summer in Alberta and this season has been particularly poor, rivalling the worst years on record for Edmonton and Calgary.

Smoke has choked the skies over Alberta this week, triggering high-risk air pollution that forced people to cancel their outdoor plans and hunker down inside. 

A few more hazy days could make this wildfire season a record-breaker for Edmonton and Calgary, as experts caution that smoky summers fed by longer, more intense wildfire seasons will become the norm.

"It's not a good story here or a happy story," said Natalie Hasell, a warning preparedness meteorologist with Environment Canada.

"The people who are susceptible to smoke are the same people, more or less, who are susceptible to heat.

"And we have seen a number of times already this year where both have happened at the same time. That could easily happen again in the not-so-far future for Alberta."

For the past 70 years, Environment Canada has tracked "smoke hours" for communities across the country. Smoke hours are counted when the haze from wildfires is so thick that visibility is reduced to 9.7 kilometres or less. 

The smokiest year on record for both Edmonton and Calgary was 2018. Between May and September of that year, Edmonton recorded 229 smoke hours.

Between May 1 and July 17 of this year, Edmonton has already recorded 194 smoke hours, already the second-highest number of hours on record.

"By the end of this season we might not be in second place anymore, if this year continues the way it has been," Hasell said in an interview Monday.

In 2018, Calgary recorded 450 smoke hours between May and September.  To date this year, the city has seen 258 smoke hours, the fourth highest year on record.

Alberta spent the weekend under a blanket of smoke with air pollution measured at a 10-plus on the Air Quality Health Index.

Developed by Health Canada, the system monitors the severity of air pollution by tracking fine particulate matter, ground-level ozone, and nitrogen dioxide. When the rating is high, people exposed to the smog face significant health risks.