1. Depletion Of The Ozone Layer
... to dramatically increase. Scientists estimate that before 1900 chlorine comprised 0.6 parts per 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 layer in the stratosphere is thinning. In ... layer. One method instituted was to ban the use of CFCs. Although this was incorporated, CFC molecules already located in the lower atmosphere will journey into the upper atmosphere and c...
- Word Count: 2746
- Approx Pages: 11
- Grade Level: High School