...This unintended consequence now haunts the nations that signed both U.N. treaties.

By JOHN HEILPRIN, Associated Press Writer Sun Aug 20, 50 PM ET

WASHINGTON - Cool your home, warm the planet. When more than two dozen countries undertook in 1989 to fix the ozone hole over Antarctica, they began replacing chloroflourocarbons in refrigerators, air conditioners and hair spray.
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But they had little idea that using other gases that contain chlorine or fluorine instead also would contribute greatly to global warming.

CFCs destroy ozone, the atmospheric layer that helps protect against the sun's most harmful rays, and trap the earth's heat, contributing to a rise in average surface temperatures.

In theory, the ban should have helped both problems. But the countries that first signed the Montreal Protocol 17 years ago failed to recognize that CFC users would seek out the cheapest available alternative.

The chemicals that replaced CFCs are better for the ozone layer, but do little to help global warming. These chemicals, too, act as a reflective layer in the atmosphere that traps heat like a greenhouse.

That effect is at odds with the intent of a second treaty, drawn up in Kyoto, Japan, in 1997 by the same countries behind the Montreal pact. In fact, the volume of greenhouse gases created as a result of the Montreal agreement's phaseout of CFCs is two times to three times the amount of global-warming carbon dioxide the Kyoto agreement is supposed to eliminate.

This unintended consequence now haunts the nations that signed both U.N. treaties.