Chlorofluorocarbons (CFCs) seemed like a wonder of modern chemistry: inert, nontoxic chemicals that could do it all, from cooling your fridge to spritzing your hair. But to the surprise of chemists, the gases seeped into the stratosphere and destroyed the ozone there to create the Antarctic ozone hole. And the hole, in turn, stunned meteorologists when it reached down to boost the ring of wind encircling the icy continent. Now it's the oceanographers' turn to scratch their heads. In an ironic twist, they have used the same CFCs that created the ozone hole to track its effects on the Southern Ocean.