life exist

Many scientists warn that the ozone "blanket" that surrounds the earth and which makes life on this planet possbile by screening out the sun’s harmful ultraviolet rays is being depleted by certain chemicals.

They say the biggest culprits are chloroflourocarbons (CFCS). These are used in air conditioners, refrigerators, cleaning solvents and plastic foams. They are also used in some countries in aerosol cans, but a number of nations have banned that use. Scientists have shown that CFCs can destroy molecules of ozone, an oxygen-liike gas naturally found in the upper atmosphere. When researchers discovered that over Halley Bay, Antarctica, a 40 percent loss in ozone occurred at certain times of the year, many scientists belived CFCs were responsible.

Also suspect is airborned methane gas, most of which come from the decomposition in rice paddles, swapms, the guts of cows and wood digestion in termites. Scientists say methane can help destroy ozone by aiding the formation of ice clouds. These act as catalysts to help CFCs do their dirty work.

But not all scientists agree that CFCs are responsible for upper atmosphere ozone loss. Robert W. Pease, professor emeritus of Physical Climatology at the University of California, Riverside, syats that ozone molecules are created at a much higher rate than the small concnetration of CFCs in the upper atmosphere can destroy them. He suggests that the same phenomenon that creates the northern and southern auroras could be a natural cause of ozone loss.