Word: polarity
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...ozone link. "The evidence isn't final," he said, "but it's strong enough." Earlier this month, results from NASA's Punta Arenas project confirmed the bad news. Not only was the ozone hole more severely depleted than ever before -- fully 50% of the gas had disappeared during the polar thaw, compared with the previous high of 40%, in 1985 -- but the CFC connection was more evident. Notes Sherwood Rowland, a chemist at the University of California at Irvine: "The measurements are cleaner this time, more detailed. They're seeing the chemical chain more clearly...
Farmer and others have concentrated their research on the so-called Antarctic ozone hole. Though world ozone levels have dropped by an estimated 3% to 7% in the past several decades, south polar levels plunge by as much as 50% each September, then rebound. The discovery of the hole was announced in 1985 by a team led by Joseph Farman, a scientist with the British Antarctic Survey. Since then, researchers have flocked south to study the phenomenon...
Farmer discovered that chlorine compounds bloom as the hole appears each year. His theory: the compounds condense onto ice crystals during the polar winter; then, as spring nears in early September, the chlorine is warmed by the sun and converted into a reactive form that can destroy ozone. The presence of fluorine in the atmosphere supports the view that these chlorine compounds are of man-made origin. "There isn't any fluorine in the upper atmosphere from any natural source," says Farmer. This suggests that the source of the accompanying chlorine is chlorofluorocarbons...
While carbon dioxide allows the warming rays of the sun to reach the earth, it blocks the excess heat that would normally reradiate out into space. As a result, the atmosphere is gradually growing warmer, thus melting the polar ice caps and raising sea levels. It may be years before scientists determine just how significant the greenhouse effect is -- but they know the process is accelerating. Sea levels are expected to rise at least a foot in just another half-century...
...standard give-and-get of movie fiction: two men of polar-opposite dispositions share their strengths and become one indomitable hero. Tuck gives Jack guts; Jack gives Tuck humanity. The old switcheroo has a nice impact, but the film's most intelligent pleasures come from the filigree work. Dante packs his movie as if it were the knapsack of a ten-year-old running away from home -- with comic-book notions, weird windup toys and a quartet of villains as grotesquely giddy as the Garbage Pail Kids...