Word: rowland
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...Many of them come from very small towns," says Tricia Rowland, who oversees Time Inc.'s college-intern programs. "By the end of the first few weeks, they realize how much they don't know. By the end of the summer, they think they've got the best experience they could have...
...under the glare of ultraviolet light. The result: free chlorine atoms, which attack ozone to form chlorine monoxide (ClO) and O2. The ClO then combines with a free oxygen atom to form O2 and a chlorine atom. The chain then repeats itself. "For every chlorine atom you release," says Rowland, "100,000 molecules of ozone are removed from the atmosphere...
...Rowland and Molina announced their conclusion: CFCs were weakening the ozone layer enough to cause a marked increase in skin cancers, perhaps enough to perturb the planet's climate by rejuggling the stratosphere's temperature profile. In 1978 the U.S. banned their use in spray cans. "People assumed the problem had been solved," recalls Rowland. But the Europeans continued to use CFCs in aerosol cans; other uses of CFCs began to increase worldwide. Says Rowland: "All along, critics complained that ozone depletion was not based on real atmospheric measurements -- until, that is, the ozone hole appeared...
...likely source of mischief making: clouds of ice particles in the polar stratosphere. Explains Rowland: "Mostly, you don't get clouds in the stratosphere because most of the water has been frozen out earlier. But if the temperature gets low enough, you start freezing out the rest." Indeed, ice may prove to be a central cause of the ozone hole, since it provides surfaces for a kind of chemistry only recently associated with reactions in the atmosphere. In a gaseous state, molecules bounce around and eventually some hit one another. But adding a surface for the molecules to collect...
Some experts do not believe the projected cutback is good enough. Says Rowland: "The Montreal agreement simply isn't sufficient to protect the ozone. We should have signed a treaty that reduced CFC production by 95% -- not 50%." Nonetheless, the Environmental Protection Agency has calculated that without the accord, a staggering 131 million additional cases of skin cancer would occur among people born before...