The Ozone Problem is Back – And Worse Than Ever

James Anderson, the winner of a Smithsonian American Ingenuity Award, has discovered the alarming link between climate change and ozone loss

With the help of spy planes and B-57 bombers, Jim Anderson discovered the link between climate change and ozone loss. (Ethan Hill)
Smithsonian Magazine | Subscribe

(Continued from page 1)

So Anderson revamped the course, doing his best to liven it up. “Every day he made something explode or set something on fire,” says Adam Cohen, an associate professor who teaches the course now. Anderson has since poured his teaching philosophy into a chemistry textbook he has been writing for years. It’s almost ready for publication, and he proudly shows off the cover he designed adorned with a zippy red Tesla, the high-end electric car. He has one on order. (Read more about the Tesla and its creator on p. 72.)

Anderson’s love of research took root early, in the machine shop that his father, chairman of the physics department at Washington State University in Pullman, built in the family’s basement. It was there that Anderson, born in 1944, built his first model plane, at age 6, and where by seventh grade he was constructing boats.

During summers with his grandparents at Lake Pend Oreille in Idaho—a retreat where he and his wife still vacation—he repaired outboard motors and built treehouses, forts, rafts and radios (“there were none except when we built them”). After majoring in physics at the University of Washington, Anderson found his life’s calling during his graduate student years at the University of Colorado.

At its Laboratory for Atmospheric and Space Physics in Boulder, he devised a way to measure very low concentrations of free radicals—clusters of atoms that carry an electric charge—in the stratosphere. “Free radicals are the Lord God of all chemical transformations,” Anderson says with the enthusiasm of a little kid for things that go boom: They serve as catalysts for everything from rusting to smog formation. The measuring device he came up with could detect concentrations of free radicals as low as one part in a trillion, equivalent to a couple of grains of salt in an Olympic-size pool, and was carried aloft by a rocket.

Figuring out how to shoot scientific instruments into space came in handy. In the 1970s and ’80s, several teams of scientists were warning that technologies as different as deodorant cans and the space shuttle were spewing all sorts of chemicals into the atmosphere with possibly disastrous effects for the ozone layer. Arguably the most threatening were industrial gases called chlorofluorocarbons (CFCs) from aerosol cans, air conditioners and refrigerators. Were those products injecting massive amounts of CFCs into the stratosphere? By 1979, using instruments carried into the stratosphere on balloons lofted from the National Scientific Balloon Facility in Palestine, Texas, Anderson and his team detected the telltale signature of CFCs. They really were reaching the stratosphere in measurable quantities.

But were they causing harm? Circumstantial evidence was pouring in, none more stunning than a discovery announced by scientists with the British Antarctic Survey in 1985: A massive hole in the ozone layer had opened up over the South Pole. The ozone layer there was 60 to 70 percent thinner than usual. A 10 percent drop in ozone thickness allows 10 percent more UV sunlight to reach the earth’s surface; 10 percent more UV will lead to a 20 to 30 percent increase in the most common forms of skin cancer, the Environmental Protection Agency calculates. If that much ozone depletion occurred over inhabited regions rather than the South Pole, cancer rates could soar.

And yet ever-cautious scientists were still not ready to declare CFCs the culprits. Anderson ran the definitive experiment. In 1987, instruments he and his team built flew aboard NASA’s ER-2 aircraft—the civilian version of the U-2 spy plane—in the Airborne Antarctic Ozone Experiment.

Scientists do not keep aircraft, or even balloons, on standby, of course. Instead, “NASA announces a field mission with a specific goal in mind and asks experimenters to take part,” says Lenny Solomon, who managed Anderson’s lab and logistics from 1978 until his “retirement” in 2009. (Less than a year later Anderson asked Solomon to come back one day a week.) NASA and the balloon facility also “send out yearly questionnaires to investigators asking if they’d like some flight time and for what reasons,” Solomon says—an offer Anderson rarely passed up.

From August to September, the ER-2s took off into the lower stratosphere from Punta Arenas, Chile, whose military was on alert over tensions with Argentina. “Night raids were being launched out of the next hangar” beside their own NASA craft, recalls Anderson. “We had 18-year-olds guarding us with AK-47s.”

Anderson finally got his free radical. His instruments achieved the first detection of chlorine monoxide, ClO, in the stratosphere. The only source of ClO is ozone destruction by chlorine. Moreover, Anderson found that the higher the concentration of ClO the lower the concentration of ozone. “That anti-correlation between ClO and ozone was a dramatic clue to what was happening,” Anderson says. His lab work had shown how quickly a given concentration of ClO makes ozone disappear. The numbers matched: The ClO they detected in the stratosphere was exactly the right concentration to explain the measured ozone loss. It was the smoking gun proving that CFCs were chomping away at the ozone layer like so many high-altitude Pac-Men.


Comment on this Story

comments powered by Disqus