A Conversation with the Smokies’ Air Specialist
Jim Renfro has been at Great Smoky Mountains National Park since coming on as a volunteer in 1984, and a lot has changed in those 36 years. Visitation has exploded, elk have returned and wildfire has forever altered the iconic Chimney Tops. But perhaps no change has been more drastic than the marked improvement in air quality that has characterized the last three decades. As the park’s air resource specialist, Renfro has had a backstage pass to that transformation.
How did you get into air quality work?
I was hired in ‘85 as a research technician and did frontcountry and backcountry social science research. Certain people here at the park moved on to other things, and I applied for a monitoring position and then it was a research position, then plant physiologist and finally air resource specialist. I did not go to school thinking, “I’m going to be an atmospheric science person,” but I’ve sure been doing it long enough, and it’s been a great field to be in. Monitoring is one of the most important things that my program does. We’re just measuring the same things every day, decade after decade. It answers so many questions; status and trends. Outreach, education, sharing what I learn—it’s something new every day.
How has the air quality picture changed since your first day in the park?
It is a dramatic and remarkable change in air quality since I’ve been here. In the early-to-mid ‘80s and throughout most of the ‘90s, the air quality was poor, violating health standards, getting worse on most fronts. Back in the ‘80s or the ‘90s, once summer hit your mountains would disappear. You’re outside in the valley looking up, and you couldn’t see the mountains through the thick white haze. If you did get a clean day and a front would come through with some Canadian air, that was the exception. Now you can look out and see green mountains and blue skies, not whitish haze, and that was more of the norm. Today, when you do get a hazy day, people notice that. Back 20 years ago it was normal. It’s a totally flip-flopped awareness.
What’s behind that change?
The National Clean Air Act Amendments of 1977 and 1990 were important laws along with other Environmental Protection Agency, state and local efforts to reduce sulfur and nitrogen emissions. All those started to make a difference and were measuring improvements. Regional haze, sulfur dioxide, huge reductions with scrubbers being put on some industrial units, and some were switching to natural gas. All those things—laws, rules, legal actions, sometimes voluntary actions—were enough to reduce millions of tons. You almost have to stop and think, what does that mean? That’s a lot. Millions of tons of sulfur and nitrogen over the past 30 years. It’s had a huge impact on what that stuff turns into downwind, and we’re measuring those changes. Just about on all fronts we’ve seen huge improvements.
How did the sudden decrease in fossil fuel use associated with the COVID-19 pandemic impacted Smokies air quality?
Globally and locally here it’s such a unique opportunity to look at the changes in air with close to no motor vehicles in the park and so much less driving throughout the country and the region. For the Southeast, our haze is still and has mostly been sulfur. Most of the sulfur is from coal-fired power plants. And they didn’t turn off. So our visibility and haze isn’t predominately from motor vehicles like some parts of the country. Air quality continues to get better, but we had this little unexpected window of dramatic reduction. I know emissions were significantly lower and I will be eager to see what the changes were here in the park from laboratory analysis. Later this year we will get some real solid numbers on how did this compare to, say, the last five years. I do expect air quality over the coming years to continue to improve.