Calgary's air quality briefly dips below China's ratings as smoke blows in from California wildfires

Calgary's air quality was rated as unhealthy as higher-polluting regions of China on Monday evening, as heavy smoke blew into the city from wildfires in California.

Environment and Climate Change Canada issued a special air quality statement for the city and surrounding areas at 7:26 p.m., warning that a cold front was moving through southern Alberta bringing in smoke that would reduce visibility and air quality.

The statement ended as of 9:19 p.m.

"What it's doing is actually mixing down some of the smoke that's higher up in the atmosphere from wildfires in California," said Ron Mark, a meteorologist with Environment Canada. "There are fires in B.C. of course as well, and some of that smoke is contributing."

Wildfires in California have destroyed more than 1,000 homes, and have forced more than 200,000 people to flee their communities. 

Mark said children, seniors and people with lung problems, like asthma, are especially at risk of negative impacts to their health from the smoke.

"Individuals may experience symptoms such as increased coughing, throat irritation, headaches or shortness of breath," the agency's statement read.

"People with lung diseases, such as asthma and COPD, can be particularly sensitive to air pollution. They will generally experience more serious health effects at lower levels. Pollution can aggravate their diseases, leading to increased medication use, doctor and emergency room visits, and hospital visits."

The World Air Quality Index, a non-profit that tracks air quality from monitoring stations around the world, rated the city's air quality as 152, in the "unhealthy" range, as of 7 p.m. That rating is comparable to China's air quality rating, which was sitting at 155. Clean air is in the 0 to 50 range.

The air in Santa Cruz, California, near the worst of the state's wildfires, was at 298, near the upper end of the scale. 

Calgary's air quality had returned to a "good" rating as of 9 p.m.

Alberta Health Services website suggests people should close outside windows and doors, avoid running air conditioners, and not using wood burning fireplaces while smoke advisories are in effect.

If you must drive somewhere, keep windows and vents closed and run car fans on recirculate, AHS said. It's also best to reduce levels of physical activity to decrease inhalation of pollutants.

Mark said the smoke was expected to be short-lived, and conditions would improve overnight.

An up-to-date list of weather alerts is available on Environment Canada's website.