In a summer defined by smoke, how one NC county forecasts air quality

For the team of people working to forecast air quality at the Forsyth County Office of Environmental Assistance and Protection, this summer has been a wildcard. Smoke from the Canadian wildfires brought more back-to-back poor air quality days than the area has seen in years. The county has been at an advantage though: It’s one of only three in the state to operate its own air quality monitoring stations and it's the only one that issues its own daily forecasts. 

So what exactly goes into making these kinds of calls?

Data from those monitoring stations play a big role. In a field next to a church on Hattie Avenue in Winston-Salem, there’s one locked behind a high chain link fence. The windowless building looks like an oversized garden shed, but it houses tens of thousands of dollars worth of equipment used to determine pollutants in the air. 

Senior Environmental Specialist Jordan Payne works to keep all that equipment up and running. On the building’s roof, he unlatches a box attached to a railing. 

“This is the box where all the air is getting sampled,” he says. 

Inside it’s filled with tangled clear tubes, each one wrapped with a different colored piece of tape. Air is pulled into the tubes, and the colors indicate which pollutant that tube is sampling for. Before being analyzed by the machines in the shed below, the air goes through a filter that looks like a round cotton pad. 

“And they do get pretty dirty, especially with all the smoke,” he says. “Kind of have to change them out a little bit more frequently when that happens.” 

That’s been happening a lot more in the last few months, as smoke from the Canadian wildfires made its way to the Triad. Payne spends hours every month at each of the county’s three stations, changing filters and making sure the analyzers are calibrated and able to provide information meteorologists need to issue air quality warnings to the public. 

Jason Bodenhamer is one of those meteorologists. Each day he issues a color-coded forecast for two main pollutants: ozone, which mainly comes from car emissions, and particulate matter, which recently has been coming from smoke. 

At the Forsyth County Office of Environmental Assistance & Protection in Winston-Salem, he gathers what he needs to put together his report for the day.

“Okay, today, I'm looking at the heat, I'm looking at the humidity, I'm looking at the winds, I'm looking at a weak stationary front to the southeast,” he says. ”Those are the weather factors that I'm looking at for today's forecast for tomorrow.”

He pulls up a map of the U.S. and Canada with little dots scattered throughout. Each one represents an air quality monitoring station. The dots show the pollution levels the monitors are measuring in real-time. 

“I can see what the air quality is doing in a lot of different places,” he says. “This has been incredibly beneficial when you have all the forest fire smokes in western Canada, we can see when the smoke has started coming down towards us. We can see it hit these sites before it ever gets to us.”

Bodenhamer says the recent wildfires are just another example of how local air quality can be deeply impacted by events happening around the world. 

“We have events where the dust from the Sahara can actually get suspended in the atmosphere, and stay suspended long enough to make it across the Atlantic Ocean, come up through the Gulf of Mexico, and hit us,” Bodenhamer says. 

More commonly though, the Triad is affected by pollution from other Southern cities.

“The way the mountains are aligned, sometimes when we get like your true southwest breeze, you know, like the Bermuda high of the summers that were very typical to see,” he says. “We can get Atlanta, Greenville, Charlotte, all lining up to where that pollution comes right up to the Triad.”

Conversely, he says if the wind changes direction, pollution produced in the Triad can end up in Charlotte.

For the most part, these past weeks of poor air quality have been an aberration. The Triad has had more poor air quality days this year than in the past seven years combined. Bodenhamer says in his 25 years as a meteorologist, he’s actually seen air quality improve as cars have become cleaner. 

“But as people do more research into what poor air quality does, we’ve found that levels that we used to think were okay years ago actually have an effect on people's health,” Bodenhamer says. 

He says they’ve learned that ozone pollution can leave what he describes as a kind of sunburn on the lung. Particle pollution can get into the bloodstream and affect heart function. That’s why he feels like his job is so critical. 

“What we're trying to do is we're trying to give people the information so they can make wise choices about their daily activities and protect themselves,” he says. 

The Forsyth County Office of Environmental Assistance and Protection issues air quality forecasts every day around 3 p.m. Residents can sign up to receive them directly by email at Enviroflash.info.