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| Causes and Consequences of Ozone Depletion |
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| Your hairspray: cause for worry? Some Sources of CFCs Hairspray Deoderant Bug Spray Processed food containers Air Conditioning |
| Chlorofluorocarbons ~Started to be used in the twenties ~In seventies, people started to become suspicious ~Drift into the stratosphere, where they are broken up by high-energy ultraviolet rays. ~Rate of release in 1972 was aproximately 800,000 tons per year- if that rate had been continued, ozone layer would have lost between 20 and 40% |
| Consequences ~Cataracts ~sunburn ~malignant melanoma ~Out of 200 different species of plants tested for sensitivity to UV-B, 2/3 of them have been proven sensitive ~25% decrease in soybeans ~Photoplankton ~Cattle ~Decreased vegetation unable to process carbon dioxide levels into glucose, results in global warming |
| TIMELINE June 1974: Rowland and Molina's paper on their discovery is published in Nature October 1978: CFCs used in aerosols are banned in the US March 1985: The Vienna convention is passed, callinng for further research and international research projects on ozone depletion. September 1987: The Montreal Protocol is signed, calling for eventual worldwide CFC reductions of 50% March 1989: Europe agrees to quicker limits on CFCs, but developing countries reject the idea |