Smoke from Canadian wildfires brings unhealthy air to large swaths of the Midwest

The smoke of Canadian forest fires hovered over several Midwest states on Saturday, providing unhealthy air warnings for at least the third day.

Air quality alerts were in effect in Iowa, Minnesota, Wisconsin and Michigan, as well as in the east of Nebraska and in certain parts of Indiana and Illinois. The forecasters said that the smoked sky would remain for much of the day.

Canadian environmental officials said smoke from forest fires would persist for certain regions on Sunday.

The air quality monitoring database based in Switzerland Iqair, which assesses air quality in real time, has listed the city of Minneapolis as having a part of the worst air pollution in the world since Friday. The air quality index (AQI) had to reach the red or unhealthy category in a wide strip of Minnesota.

AQI is a system used to communicate the amount of air pollution in the air. It breaks down pollution into six categories and colors, as well as advice on what is and is not sure. They range from “good” (the green color) to “dangerous” (brown).

People with lung disease, heart disease, children, elderly and pregnant women are most sensitive to poor respiratory conditions.

“What was unique in this postponement is that we have had this prolonged extent of smoke particles to the surface, so this is where we really had air quality in red here in recent days,” said Joe Strus, meteorologist of the National Weather Service in the Minneapolis – Paul region in Minnesota.

“We have somehow treated this day after day, when you go outside and you can taste smoke, you can feel it,” said Strus. “Sometimes we have been at higher concentrations than the others. Other times, it looks a little foggy there.”

The air improved on Saturday, he said, in particular in twin cities and southwest Minnesota, but state health officials warned that the conditions could remain unhealthy for sensitive groups until Monday.

The officials said that smoke could spread as far in the south as Tennessee and Missouri.

The EPA air quality index converts all levels of pollutants into one number. The lower the number, the better. Everything below 50 is classified as “healthy”. Fifty to 100 is “moderate” while 100-150 is unhealthy for “sensitive groups”. Everything that is more than 150 is bad for everyone. Parties of Minnesota exceeded this number on Saturday.

Health officials advise people with asthma and other pulmonary diseases, heart disease, children and older adults to avoid prolonged smoke exposure and limit painful activities. They said they were to avoid burning things that could worsen air pollution and keep the windows and the doors closed.

“This is something that is part of our summer here in recent years,” said Strus, “and I think many of us are looking forward to seeing a little more movement in atmospheric winds and we will be able to disperse part of smoke from here in the coming days.”

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