CFC's A Threat??
...naturally occurring phenomenon that is highly unlikely to occur anywhere else. NASA had said that a similar hole to the ozone could develop in the Antarctic. Some people had proved it has developed, but not because of CFC's. The hole had already been seen there. The hole is affected by wind, temperature, and the chemistry of the South Pole. Ellsaesser said that unless more chlorine was added to the stratosphere the hole would not become any more important. The amount of ultraviolet radiation reaching the Earth's surface is not increasing. The U. V. rays reaching the Earth's surface has not increased but has fallen in recent years. It has dropped about 0.7 percent per year since 1974. Small increases in UV levels are harmless to plant and animal life. Only in Antarctica has it appeared that CFC's increased the UV levels. One researcher has explained that the higher UV levels in Antarctica may have reduced phytoplankton growth rates each spring by 6% to 12%. UV rays could cause a more serious injury to plant...