In 1985, British scientists discovered a hole, the size of the United States, in the ozone layer; the hole had been occurring over Antarctica each spring since 1979 (World watch Paper 87). Although the theory said that a group of widely used chemicals called chloroflourocarbons (CFC's) would someday evade the upper atmosphere ozone, none of the models predicted it would be over the South Pole or that it would be so severe. Also during this period, the expected rate of the greenhouse warming accelerated because its relationship to CFC's became clearer to scientists (Miller and Mintzer). In the fall of 1986, the U.S. and European users and producers of CFC's and DuPont Chemicals, the largest single CFC manufacturer, endorsed limits on CFC production (Miller and Mintzer). Government decisions concerning Ozone depletion will influence the greenhouse problem, the warming of the earth as heat-trapping gases build in the atmosphere. CFC's contribute to the greenhouse effect as well as to the changes predicted in the distribution of ozone (Miller and Mintzer). The discovery of the hole over Antarctica prompted 35 countries to sign an international agreement - the Montreal Protocol - which is aimed at trying to halve most CFC emissions by 1998.
Ozone is formed in the stratosphere when ultra-violet radiation breaks diatomic molecules of oxygen. Once split, two oxygen atoms combine with two molecules of diatomic oxygen to form ozone. To keep the ozone-oxygen balance in the atmosphere, ozone molecules are also broken apart by ultraviolet rays into oxygen, oxygen, and ozone in the stratosphere. However, reactions between ozone molecules and chlorine, nitrogen, and bromine oxides can upset the chemical balance and reduce the amount of ozone (ozone depletion) (Miller and Mintzer). As the ozone diminishes in the upper atmosphere, the earth receives more ultraviolet radiation, which promotes skin cancers and cataracts and depresses the hu...