ST. LOUIS, MISSOURI —
There’s something unusual going on in the skies over St. Louis in the U.S. Midwestern state of Missouri. Students at Saint Louis University are launching weather balloons as part of a nationwide study funded by the U.S. space agency NASA, aimed at improving our understanding of air pollution and global climate.
A small group of Saint Louis University students are huddled around a laptop and radio receiver set up outside the Saint Louis Science Center planetarium. They’re getting ready to participate in the NASA mission to measure ozone ― a gas that both protects and pollutes the planet.
Inside a small Styrofoam box are a GPS, and two little instruments that measure temperature, humidity, air pressure and ozone. A transmitter in the box broadcasts the data to a 2-meter-tall antenna connected to that beeping radio receiver. From there, an old-school modem translates the audio signal into ones and zeroes that the laptop converts into air quality measurements.
Once the students have checked that all the equipment is working, the next step is to attach the Styrofoam box with its instruments to a weather balloon that will carry everything up into the atmosphere.
Once it is filled the helium, the balloon is 2 to 3 meters in diameter. The goal is to give it enough lift to carry its cargo up about 30 kilometers into the stratosphere. That’s around three times as high as commercial jets fly.
Gary Morris, a professor at Valparaiso University in Indiana and the lead trainer for the NASA ozone balloon project, is overseeing the launch. St. Louis is one of seven sites, from Colorado to Florida, involved in the nationwide study. Morris says NASA wants to get more data on ozone because of the important roles it plays in our atmosphere ― both good and bad.
High up in the stratosphere, the ozone layer absorbs sunlight and keeps harmful ultraviolet radiation from reaching the earth.
But down near the ground, emissions from sources like petrochemical plants and cars can form ozone pollution and smog, which can exacerbate respiratory problems like asthma.
“It’s especially difficult on children who are still developing," Morris said. "So children who grow up in areas that are chronically exposed to high levels of ozone have more frequent rates of asthma.”
Saint Louis University’s ozone study is being led by Jack Fishman, who worked for NASA for more than 30 years, studying air pollution and atmospheric chemistry.
He says while regulations have led to lower ozone pollution in urban areas of the U.S., ozone levels outside of cities have continued to rise.
“A lot of it has to do with the increased anthropogenic activity, industrial activity in eastern Asia,” Fishman said.
He says that’s because pollution is being blown across the Pacific by global air currents in the upper atmosphere.
"So we’ve crossed the threshold of increasing ozone concentrations whereby we actually see enough ozone, in the atmosphere, that crop growth is inhibited, forest growth is being impeded.”
In 2010, Fishman published a study showing that ozone damage to the U.S. soybean crop alone may cost farmers hundreds of millions of dollars each year.
And he says that, like carbon dioxide, ozone absorbs heat and affects climate.
“So this project is trying to understand the complexity of the chemistry and the clouds and other processes, meteorological processes, that impact local meteorology," Fishman said, "which in turn form the big picture of climate…and in turn climate change.”
Back at the Saint Louis Science Center, the balloon and its payload swoop upwards. Saint Louis University senior William Iwasko is one of four undergraduates on the launch team. He says launching the weather balloons by the planetarium, in a public park, gives kids who come by a chance to see science in action.
“And it helps to build their excitement for science and especially meteorology, so we hope we’re developing little meteorologists here,” Iwasko said.
Zack Crawford, 7, says when he grows up, he wants to be…a fireman. But the balloon launch definitely made an impression.
“That was amazing," Zack said. "It’s so high that I can’t even see it.”
The ozone balloon project runs through the end of September.