Ozone Layer

The ozone layer lies at between 12 to 24 km above the surface of the earth. Ozone is a gas with a fishy smell. Its molecules are made of three oxygen atoms linked together (o3). Ozone is a formed from normal oxygen in ultraviolet light. It can also be broken down in ultraviolet light. In the upper atmosphere the making and breaking down of ozon balance each other out so the amount of ozone does not change appreciably.

The layer of ozone in the upper atmosphere stops too much ultraviolet rays of the sun from reaching the earth’ surface. Ultraviolet rays can damage cells, causing mutations of the body cells. It may also cause skin cancer.

This protective ozone layer is being destroyed slowly by substances called chloro-fluoro-carbons (CFCs) which are being used in aerosols in making fast food cartoons and in insulating cavity walls, in refrigeration system and in air conditioning. These CFCs slowly diffuse up to the upper layer of the atmosphere, where the ultraviolet light from the sum reacts with them producing chlorine. The chlorine produced then reacts with ozone and breaks it down. This has formed a hole in the ozone layer. It appears over the Antarctic zone and its sizes reaches maximum in the spring season.

If the ultraviolet light is not cut down by the ozone layer, we will be in trouble as we are now.

Scientists and people in general who are conscious of this situation are trying hard to stop further worsening of this situation.

The amount of CFCs used is being reduced. In October 1987, an international agreement was signed in Canada to reduce CFCs emission by 50% of the 1986 levels by 1999. recently, it has been reported that the hole in the ozone layer is smaller now than it was before. However, CFCs may exist in the atmosphere for centuries.