Has the sky seemed hazy to you? Wildfires are to blame

Has the sky looked a bit hazy to you lately? Have sunsets seemed a bit off? You’re not imagining it — northern wildfires are the culprit.

Wildfires began to sprout in Alberta, Canada, in early May, bolstered by unusually warm dry weather and strong winds. The province declared a state of emergency on May 6 as more blazes erupted. As of May 10, 136 wildfires burned throughout Canada — 31 of which were uncontrolled at the time. More than 29,000 residents have since evacuated Alberta and the neighboring province British Columbia.

The resulting smoke from the blazes has wafted over much of the northern U.S. It started noticeably clouding Iowa skies around Tuesday, creating cloudlike cover and red, hazy sunsets. That smoke was between 15,000 and 20,000 feet in the air.

But as another round rolls through the state, it will be closer to the ground — and, as a result, bring more of a health risk. The smoke started fanning across northwest Iowa Thursday morning.

“We’ve had smoke in the summer several years in a row” prior to last summer, said meteorologist John Haase of the National Weather Service’s Quad Cities bureau. “This is, I would say, the earliest (in the year) I’ve seen it.”

How did the smoke get here?

Some of the wildfires in question are more than 2,000 miles away from Cedar Rapids. So, how did their smoke make its way to Iowa? And why is it just now becoming a health concern?

Winds aloft — or, the winds at different levels of the atmosphere, up above surface level — are the cause. Specifically, their northwest direction that pushed them out of western Canada and toward Iowa, Haase said.

While Iowa skies have been hazy since Tuesday, the situation turned a bit riskier because of the cold front passing through the state. The cooler air sinks to the ground — bringing the smoke with it. The cold front hit Cedar Rapids in the early hours of Friday morning.

Visibility fell as low as one mile in Minnesota, Nebraska and the Dakotas, Haase said. Visibility in Eastern Iowa should only drop to around four miles.

Will the smoke impact our health?

While the haziness has been in the air for a few days, the smoke didn’t significantly register on the Iowa Department of Natural Resource’s Air Quality Index until Thursday morning in northwest Iowa.

That’s because the monitors are close to ground level and didn’t catch a whiff of smoke until it sunk with the cold front, said John Gering, unit leader of the Iowa DNR’s ambient air monitoring group.

On Thursday afternoon, the AQI Fire and Smoke Map depicted a wave of unhealthy air quality passing through Iowa. At first, locations would experience levels unhealthy for sensitive groups — like older adults, children and those with respiratory or heart disease. Then, as more smoke settled in, levels turned to those considered unhealthy for everyone.

Gering advised sensitive groups to move activities indoors or reschedule outdoor activities. The population should avoid prolonged or heavy exertion and take more breaks during outdoor activities.

Will the smoke impact agriculture?

Farmers may be tending to their fields with smoke overhead — but it shouldn’t affect their crops, Haase said.

If the smoke gets thick enough, it could act like a cloud layer. Temperatures on the ground may be cooler than they would be otherwise. But sunlight will still make it through to the plants below.

“It’s kind of like filtered sunshine,” Haase said.

How long will the smoke stick around?

The northwest winds are changing course Friday; streams should start coming from the west. So, smoke should clear out of Iowa by Friday afternoon, aside from some intermittent patches that may pass over through the weekend.

But that most likely won’t be the last Iowa sees of the haziness. With around 30 wildfires still raging out of control in Canada, more smoke is bound to travel southeast at some point, Haase said.

“It’s all about which direction the winds are coming from,” he said. “You’ve got to wait for another pattern change to a northwest flow again. At some point, it’ll happen again, and I’m sure the smoke will come back again.”

Brittney J. Miller is the Energy & Environment Reporter for The Gazette and a corps member with Report for America, a national service program that places journalists in local newsrooms to report on under-covered issues.

Comments: (319) 398-8370; brittney.miller@thegazette.com