It intensifies during January and February before tailing off in April as temperatures rise. Circular winds, known as a vortex, trap air, giving chemicals the chance to react with the ozone. Scientists are establishing a link between global warming and ozone depletion, Proffitt told The Associated Press. And cold means ozone depletion. In 1989, a gradual, global ban was imposed on chlorofluorocarbons, chemicals commonly used in aerosol sprays, refrigerators and air conditioners.
Chlorofluorocarbons contain chlorine, one of the major destroyers of ozone.
But bromides, another destroyer often used in weed and pest killers, are not being eliminated as quickly, particularly in developing countries. Measurements of ozone depletion vary from year to year, making it difficult for scientists to determine the long-term environmental impact of changes in the ozone layer. When we start disturbing it, we don't really know what it will do.