Unintended Consequences

These are proud times for atmospheric chemists. This year is the last year that American industry will produce chlorofluorocarbons, the ozone-destroying compounds used in such things as refrigerators and insulation. The 130-nation agreement that led to the banning of CFCs, an extension of the Montreal Protocol of 1987, was triggered by the persuasive research of atmospheric chemists. Over the past few years CFC production has already withered drastically, so 1995 may also be the first year in decades that levels of atmospheric chlorine--the ingredient in CFCs that actually destroys the ozone--fall rather than rise. If we’re lucky, the decline in chlorine will soon lead to a decline in ozone destruction; in 70 years or so our abused ozone layer may return to its normal thickness. You have to agree that the world has done an incredible job and reacted incredibly quickly, says John Daniel of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado. There’s absolutely no telling what would have happened if we had waited ten years to do something.