1. Depletion Of The Ozone Layer
... due to natural processes. Thinning of the ozone layer has been caused by a variety of ozone destroying chemicals released by human activities. More than half the damage has been caused by chlorofluorocarbons. For over 50 years, chlorofluorocarbons,(CFCs), were thought of as miracle substances. They are stable, nonflammable, ... billion (pp.) of the stratosphere. Today, the chlorine level is about 3.5 pp., and growing by more than 1.0 pp. per decade. The net effect is to destroy ozone faster than it is naturally created. Scientists are finding that under this assault the protective ozone ...
- Word Count: 2746
- Approx Pages: 11
- Grade Level: High School