1. Ozone Depletion Ozone produced from the interaction of hydrocarbons and oxides in the presence of sunlight At ground level, ozone is a pollutant; in the upper atmosphere it protects earth from excess radiation from sun In 1970’s scientists discovered the ozone layer in stratosphere was depleting The resulting increased radiation on earth has been found to result in increased skin cancers and agricultural damage

2. Ozone Depletion Caused primarily by substance found in commercial products called chlorofluorocarbons (CFC) CFC’s were developed as commercial products to serve as refrigerants and propellants for aerosols such as hair spray The external cost of using CFC’s wasn’t confined to individual country

3. Ozone Depletion In 1987, an international agreement was passed that called for phasing out of chemicals The Montreal Protocol was initially signed by 24 nations; currently ratified by 196 countries

4. Under Montreal Protocol 1.Developed countries are to eliminate substances more quickly than developing countries 2.Developed countries contribute to fund to help finance transition by developing countries 3.Trade involving CFC’s and related substances between signatories and non-signatories is restricted Agreement widely considered successful international action to address global environmental problem