Ozone

In 1985, scientists reported a change in the atmosphere—a hole, or thinning of ozone in the atmosphere, over Antarctica. Scientists were not sure about what was causing it.

Most scientists believe that man-made chemicals are destroying the ozone. But finding the major cause has not helped solve the problem. In fact, experts say the problem seems to be spreading. Scientists also have found signs of ozone loss in other parts of the atmosphere.

Ozone is found both in the air we breathe and in the upper atmosphere. Near the earth, ozone in the air is a danger to life. It is a waste product. But ozone forms in the upper atmosphere through the action of solar (the sun's) radiation. Once formed, the ozone blocks harmful radiation from reaching the earth. Scientists say a reduce in ozone and an increase in the harmful radiation will cause many more cases of skin cancer and will harm crops, animals and fish.

Scientists began to study the condition of ozone in the atmosphere in March 1988. The report said temperatures in the hole are getting colder. It is about eight degrees colder 15 kilometers above the earth than it was in 1979. Scientists think the first loss of ozone reduces the amount of solar energy the atmosphere can take in. This cools the atmosphere, increases ice cloud production and leads to more ozone loss.

Another report said that scientists found signs that the ozone problem has spread. The study shows that the loss of ozone over the areas with larger population in North America and Europe was at least three times greater than scientists had thought. The ozone levels are reduced much more seriously during winter months than in warmer months. This is not surprising, because the amount of ozone in the atmosphere changes with the temperature.

Why has the ozone problem developed? No one knows for sure. An international effort is being made to stop the loss of ozone in the atmosphere. But many experts fear the effort will not produce results fast enough to prevent harm to life on the earth.