Ozone Depletion Essay Research Paper The Earths

Ozone Depletion Essay, Research Paper

The Earth?s ozone layer shields all life on the planet from the sun?s harmful radiation and is extremely important to all life on the planet, but we as a human race are now faced with a very important question. This question is, ?Is the Earth?s

ozone layer really depleting, and if it is, is it really a threat?? There is evidence that less protection from ultraviolet rays will, over time, lead to increased amounts skin cancer, cataract, and even crop damage. With cooperation with over 140 oth

countries, the United States is ridding the Earth of the production of ozone-depleting substances in a world wide effort to save our ozone layer. Although, before I try to go and answer the big question I must first understand the chemistry involved.

The Earth?s atmosphere is divided into many layers such as the troposphere and the stratosphere and the majority of what is known as ozone is located in the stratosphere. Ozone is a molecule consisting of three oxygen atoms and it is blue in

color and has a strong odor. In the entire atmosphere, out of each ten million air molecules, about two million are normal oxygen. Although, there are even less ozone molecules at three in ten million, ozone plays a primary part in the protection of a

life on the planet. The ozone layer is so important because it absorbs a portion of the radiation from the sun which prevents it from reaching the Earth?s surface and harming living organisms. The most harmful of the radiation that it absorbs is the

pe of ultraviolet light known as UV-B which has been associated with forms of skin cancer, cataracts, and harm to some crops, certain materials, and some kinds of marine life.

In the course of any given day, ozone molecules are continually being formed and destroyed in the atmosphere and the total amount of it remains fairly stable but in recent years there has been some evidence that the rate at which ozone is being

destroyed is increasing. The evidence is very plain and simple. It is a giant ?hole? in the ozone layer over Antarctica which can be seen in the satellite photo below.

The red area in the center of the photo represents the ?hole?, or lack of ozone, that exists over Antarctica. The ozone hole is a well-defined, massive obliteration of the ozone layer over Antarctica which occurs each Antarctic spring. This area consi

s of 70% less ozone than what is usually found there. This is the strongest piece of evidence that exists today regarding the loss of ozone. This proves that something must be going wrong.

What many researchers have found goes back about fifty years ago when chlorofluorocarbons, or CFCs, came into play. They were thought of as wonder materials because they were highly stable, nonflammable, low in toxicity, and very

inexpensive to produce. After awhile, CFCs became very useful as refrigerants, solvents, foam blowing agents, and in several other smaller operations. Other chlorine containing compounds include substances like methyl chloroform, carbon tetrachloride,

nd halogens. All of these compounds have atmospheric lifetimes long enough to permit them to be moved by winds into the stratosphere and because they emit bromine and chlorine when they break down, they damage the ozone layer.

In the early 1970s, scientists started to examine the impacts of various substances which consist of chlorine on the ozone layer. They found that chlorine from swimming pools, sea salt, volcanoes, and industrial plants does not reach the

stratosphere because the chlorine compounds from these origins readily combine with water and then they rain out of the troposphere without ever coming close enough to damage the ozone layer. However, they found that CFCs are very stable and do not dis

lve in rain and therefore cannot be removed from the atmosphere through natural processes. In fact, the CFCs are so stable that they can only be broken down from exposure to strong UV radiation. Once the CFC molecule has been broken down it releases a