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
mic chlorine. Just one of these chlorine atoms can obliterate over 100,000 ozone molecules. This causes ozone to be destroyed faster then it is naturally created.
Above is a basic outline of the ozone depletion process. First, CFCs and other ozone depleting chemicals are released because of human activity and then they rise into the stratosphere where the ozone layer is located. The ultraviolet rays then
break down the CFCs, releasing chlorine which then goes on to destroy thousands of ozone molecules. With a lack of ozone more ultraviolet radiation becomes able to pass through the atmosphere and with increased amounts of the ultraviolet radiation many
roblems take place with the life on the planet. Look at what is happening to it.
There hazardous impacts on health from the depletion of the ozone layer which are described below. First we have large increases in skin cancer. In fact, according to the EPA, or the Environmental Protection Agency, if the ozone layer is
depleted any more then three different types of skin cancer would increase.
Two of the most common types, basal and squamos cell skin cancers, are now affecting 500,000 people annually in America alone. However, these cancers are treatable if discovered early. Malignant melanoma, the third type, is very rare but much more har
ul. Nearly 25,000 instances presently occur each year, resulting in 5,000 deaths and being responsible for almost 65 percent of all skin cancer deaths.
Another dangerous health effect is suppression of the human immune system . According to the EPA, studies suggest that exposure to ultraviolet radiation reduces the ability of the immune system to defend the body from certain diseases.
Also, UV radiation can cause damage to the human eye. Too much radiation can harm the cornea and conjunctiva, the lens, and the retina. Extended exposure to UV radiation has increased the amounts of people experiencing cataracts, limiting vision.
Other problems that are linked with ozone depletion are damage to crops and certain marine organisms. UV radiation harmfully impacts plant growth which results in dwindling leaf size and a limited area for energy absorption from the sun.
Two marine organisms, phytoplankton and zooplankton, serve crucial parts in extensive ecological food chains but are very sensitive to ultraviolet radiation because the UV rays are absorbed by only a small amount of cells, making larger life-forms bette
protected but single-celled organisms endangered. Recent studies from the Environmental Policy Institute and the Institute for Energy and Environmental Research have shown that some plankton species are already at their maximum tolerance of ultraviolet
adiation. Therefore, the littlest increase in radiation levels could dramatically affect the aquatic ecosystem.
So now that I have assessed all of the previous information I can now answer the question of whether or not ozone depletion is an ?Environmental Wacko? idea or an actual issue that needs serious attention. Ozone depletion is a bad thing and if
the ozone layer was actually depleting at a dramatic rate then it would be a serious topic that would have to be met with. All life on Earth could not sustain life for very long without it because we would all die of cancer in a matter of years. The o
ne layer is essential to our survival. However, it does not seem to me that the ozone will be leaving us very soon because there is an enormous amount of it. Despite this, I do think that it is possible that the ozone may be reducing at a very slow ra
and that this may be causing some problems. In the long run, it may hurt the ecosystems of the Earth and that is why we should view the evidence at hand and do something to stop it. All that we need to do is to cut the use of CFCs. Ozone depletion i
definitely not what the ?Talking Heads? and the ?Environmental Wackos? make it out to be because if we act now we only have to do something small.
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