And now, a few words about the Ozone Layer...
Awarding Our Atmosphere More Attention
by Michele Woodruff
The Earth spans many conversations every day. There are innumerable reasons to cherish our Earth. This is our home. The sea, rivers, land, desert, mountains, air, moon, sun, animals, and clouds are part of our home. These are reasons to care for the environment.
Imagine the future. You're not living any more, but your great-grandchildren are. All they eat is canned food, because live animals and plants are sick from garbage and toxins. A majority of your family have skin cancer, for there is not much left of the ozone layer. Oh, yes, that's a tremendous problem: The deterioration of the ozone layer. The ozone layer is a very important reason to care for the environment.
The ozone layer is a three-mile thick area heavily concentrated with ozone. Ozone is an allotropic form of oxygen. As a gas, it is a light blue and has a sharp odor. It is explosive and poisonous, even at low concentrations. The ozone molecule is very active. Sometimes it is used in water treatment to kill bacteria. It is also used as a bleach for paper and fabrics. The main interest of the ozone is its ability to absorb ultraviolet light. Most of sunlight in the wavelength of ultraviolet is absorbed by ozone in the stratosphere.
The ozone in the lower regions of the Earth's atmosphere contributes to air pollution. It can kill plants and irritate a person's nose and eyes. Ozone can build up when sunlight acts on nitrogen oxides from automobile exhaust fumes. Ozone also changes hydrocarbons from motor vehicles and some factories into pollutants that can be found in smog. Ozone is also known to cause respiratory problems.
Approximately twelve miles above the Earth's surface lies the stratosphere. It sits between the troposphere (the closest layer to the Earth) and the mesosphere. The stratosphere is the layer in the Earth's atmosphere where there is the highest concentration of ozone. There are about six parts ozone per million parts of air. The ozone layer blocks from the Earth a lot of the ultraviolet rays the sun gives off. Without the ozone layer, life on earth could not exist.
Since the 1970's, scientist's have detected a thinning of the ozone layer over Antarctica, probably due to air pollutants. Chloroflourocarbons (CFCs) contributed to most of the chlorine involved in the breakdown of ozone in the stratosphere. CFCs were in items such as cleaning solvents, refrigerants, and aerosol sprays. CFC's don't react with other gases in the atmosphere and thus rise slowly, unchanged, to the upper atmosphere. There, ultraviolet radiation from the sun causes the breakup of the CFCs, releasing atoms of chlorine. The chlorine then acts as a catalyst that helps convert ozone into ordinary oxygen. CFCs have a long lifetime, and their ozone-destroying effects are expected to last for at least fifty years.
The ozone layer prevents most UV rays from entering the Earth's atmosphere, yet because of the hole in the ozone layer, the harmful rays can enter.
Ultraviolet radiation impacts life as we know it. It has been found to kill microscopic marine organisms that form the base of the food chain of the world's organisms, which would thus affect the local food supply. A decrease in ozone concentration can dramatically increase the incidence of skin cancer. UV radiation can harm living tissue and be biologically damaging. Ultraviolet radiation also kills plant life, causes eye cancer in cattle, and breaks down certain plastics. This is just one reason of millions that we must care for our environment. We now know about CFCs and their negative effects. We are still suffering for our mistakes. We must learn to respect our Earth more. The answer lies not only in fixing our mistakes, but also in learning from them. We must think about the environment every day. Maybe, if scientists had given more regard to the effect on the environment from Chloroflourocarbons earlier, there wouldn't be such a large hole in the ozone layer.