Ozone (O3) is a molecule consisting of three oxygen atoms, similar to the oxygen we breathe (O2), however oxygen consists of only two oxygen atoms. In the stratosphere, a region high up in the upper atmosphere, light rays are responsible for the breaking down of oxygen (O2), breathable oxygen into its two separate oxygen atoms. Lone oxygen atoms are markedly reactive. When a lone oxygen atom comes into contact with a breathable oxygen molecule (O2) it combines to form ozone (O3). The ozone layer is a small residual amount of ozone concentrated in a band in the upper atmosphere. This band of concentrated ozone resides approximately between twenty and forty kilometers high in the stratosphere. The ozone layer reactions that both create and destroy ozone has come into a dynamic equilibrium. This dynamic equilibrium is very delicate and resulted during atmospheric formation (Environment Canada, 1996).
Ozone, however, is very rare even in the ozone layer.
Oxygen makes up approximately twenty percent of air and ozone makes up only 3 x 10-5 percent of air. Furthermore, this minuscule amount of ozone is enough to protect the earth from most ultraviolet light. Ozone prevents most UV-B radiation from reaching the surface of the earth (Environment Canada, 1996).
Ozone is very important to life on earth because the harmfulness of high-energy UV-B radiation stems from the high energy of these light rays, enabling them to penetrate deeply into water, plant tissue and epidermal tissue of animals. Increased UV-B radiation results in harming the metabolic system of cells and ultimately damage to genetic material present in effected cells. Living organisms on the surface of the earth have always been exposed to some, and only slightly differing levels of UV-B radiation depending of geographic location and season. Through evolution, cellular repair mechanisms have evolved to...