Friday Find: How NOAA researchers tackled a 'bear' of an air pollution problem

Not just toying around

In the 1990s, the Great Smoky Mountains had a major problem. Air pollution caused by high levels of nitrogen and sulfur was creating an unhealthy situation. Air quality was so bad that the region’s popular National Park was sometimes closed to visitors.

“People have always loved to visit and look out over the vistas,” says LaToya Myles, Deputy Director of NOAA’s Air Resources Lab. “On a good clear day you can see for miles and miles and miles. A lot of visitors would come expecting great views but they ended up not being able to see anything. There was just this thick haze of ozone.”

Ozone is formed at the ground level when nitrogen oxides and volatile organic compounds react with each other in sunlight and hot temperatures. Most people know it as “smog” and although it is associated with urban areas, it can form anywhere. Ground ozone – unlike the “good ozone” of the upper atmosphere which protects the earth from ultraviolet radiation – can trigger a variety of health problems, particularly for vulnerable populations like children, the elderly, and people who have asthma.

“You’d turn on the news and it seemed like every night on the news someone from the midwest was being interviewed — they drove all night to get to the great Smokies and found the gates locked due to bad air,” says Will Pendergrass, a physical scientist who has worked at NOAA since 1991. Pendergrass led the Eastern Tennessee Ozone Study (ETOS) in 1999, when NOAA was just beginning to develop an air quality research program.

A new way to study air quality

People at the NOAA lab in Oak Ridge had been doing routine studies out in front of the building for years — sending tethered balloons high up into the atmosphere with instruments attached to collect all kinds of air quality data. In the 1990s, the team was able to add ozone sampling, too, after state political leaders fought for funding, allowing Pendergrass and his team to set up a new kind of sampling system.

“Eastern Tennessee is like corduroy pants,” Myles explains. “We have ridges, valleys, ridges, valleys over and over again. Will positioned his instruments in both the ridges and valleys, which made it very unique.”

Pendergrass also used ARL’s HYSPLIT system to analyze air movement, enabling researchers to get a very detailed picture of pollution moving across the continent – including information on where it originated and where it eventually nestled or lingered. Previously, there had not been much data about the impact of topography on the movement or formation of pollution.

ARL’s team eventually found that one of the sources for pollution in the region was the local power plants run by the Tennessee Valley Authority. But another major contributor to ozone pollution was very large coal-fired facilities, far away in the Ohio Valley.

“If the wind was coming from the right direction we were also getting pollution from New England, and also Atlanta if the wind was from the south,” Pendergrass explains.

Bearing witness to bad air

As they gathered data, researchers were searching for a way to tell the story of the pollution and its impacts. A local cartoonist named Charlie Daniels had published a comic strip that featured a bear chasing tourists to try to steal their gas masks. That gave Pendergrass an idea in 2006: Why not outfit a bunch of stuffed bears with tiny masks for people attending the next air quality conference in the region? The cuteness of the little stuffed bears could illustrate that the pollution was bad for wildlife and the ecosystem, as well as people. (It should be noted that stuffed black bears are one of the region’s most popular souvenirs, and are sold in almost every roadside shop near this, the nation’s most visited national park offsite link.)

Pendergrass provided testimony to Congress about his federally-funded ozone studies several times. More information was also provided by the U.S. Environmental Protection Agency, the National Atmospheric Deposition Program offsite link and some state and local health departments.  Eventually, federal air quality rules were strengthened to address ozone pollution as a problem with nationwide causes.

“I found it very irritating to not be able to take my sons and their friends up into the mountains because of air quality restrictions,” recalls Pendergrass, who is soon to retire from federal service. “I think it's just odd that the Boy Scouts had portable ozone monitoring equipment back then, but we even did a two-day citizen science study where we hiked up and down with sensors on our backpacks! We can go hiking without needing the gas mask anymore.”