We often hear the word "ozone" especially in today's world where the environment is in danger due to pollution and other human excesses. But what exactly is ozone? Ozone is one of the many naturally occurring trace gases including methane, carbon dioxide and nitrous oxide that comprise the Earth's atmosphere. In geek terms, ozone is an allotrope of oxygen which means that its molecules consist of three oxygen atoms instead of the more stable O2.

Ozone gas exists mainly in our planet's atmosphere in low concentrations but it is also present on ground level where it is considered an air pollutant with damaging effects on lung functions. Nevertheless, ozone performs a very critical function in the earth's upper atmosphere - it blocks most of the harmful ultraviolet rays and prevents it from reaching the surface of the earth.

Ozone, as a trace gas, also helps keep the earth's temperature at a level that will permit life to flourish. Known as the greenhouse effect, trace gases like ozone allow the sun's rays to pass through to reach the earth and traps the heat. Because of these two very critical functions, blocking hazardous UV rays and keeping the earth's surface warm enough for all living organisms, ozone is a very important trace gas.

But now, the earth's protective ozone layer is in a constant rate of depletion. It has been discovered that layer of ozone gas covering the entire planet has been thinning out, with significant holes already developing, especially in the atmosphere above the Antarctic.

This has fuelled worldwide concern especially since it was known that the main cause of the ozone depletion is the chlorofluorocarbons (CFC's) produced by humans in various technological applications such as refrigeration and air conditioning. Even very small amounts of CFC gas can breakdown large amounts of ozone, contributing to the growing problem of ozone depletion. Today, efforts have been made to ban CFC's as well as monitor the earth?s ozone layer more closely.