Another Stratospheric Warning
NEW Environmental Protection Agency figures show increased loss of ozone over the United States. Washington should take the lead in preventing further damage to the Earth's atmosphere. Scientists may differ over the significance of a few percentage points increase over past estimates of ozone loss. And they may differ on projections of the number of cancer cases expected to result from increased exposure to ultraviolet rays normally blocked by ozone. But experts around the globe are united in their concern about the fragility of an atmosphere bombarded by man-made chemicals.
Ozone is disappearing most alarmingly over the Earth's polar regions. Losses in the far south and far north regions each spring are in the range of 50 percent. The famous ozone hole over Antarctica affects latitudes that include parts of Australia and South America. A similar, expanding ozone gap may be developing in northern latitudes too, scientists warn.
The political response to ozone depletion has been strong. The Montreal conference of 1987 set the goal of a 50 percent reduction in the production of chloroflourocarbons (CFCs), the industrial chemicals that cause most ozone loss. At a London conference last June, developed nations, including the US, Western Europe, and Japan, committed themselves to a 100 percent phase-out of CFCs by the year 2000. Developing nations were given until 2010. In light of new ozone findings, those timetables should be rec onsidered.
The US lags way behind Germany, Norway, and Sweden, for example, which have pledged to rid themselves of CFCs by the end of 1995. Alternatives to CFCs and other ozone-depleting chemicals are quickly being developed.
CFCs do double damage - destroying ozone and adding to the ``greenhouse effect'' by trapping heat in the atmosphere. The latter problem, though, is caused largely by the carbon dioxide released when fossil fuels are burned. The US has been reluctant to tackle this problem, fearing the economic implications. But when something as important as a properly functioning atmosphere is at stake, reluctance should give way.
