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Are We Really In Danger? Essay, Research Paper

Are We Really In Danger?

Lately, when some environmental problem arises, scientists, experts, and the media quickly put people as the source. When it comes to the issue of the deteriorating environment, one can find an almost infinite amount of information stating that we are to blame for the hole in the ozone layer or we are to blame for global warming. The information may be persuading, but when one looks at the other side of the story, a whole new philosophy about the environment develops, one that deals with mother nature s influence on the environment.

When it comes to ozone depletion, there is much disagreement over what causes it. But recent information seems to lean toward an idea that humans are not at fault for the large hole over Antarctica. First, let s take a crash course on what ozone is. It is a molecule that is made up of three oxygen atoms bonded together, O3. Ozone is found in the upper layers of the atmosphere and blocks out a majority of the sun s ultraviolet rays. Ozone is also found in low concentrations in the lower atmosphere because it is emitted by automobile exhaust. It can be very harmful if inhaled. In worst case scenarios, a total depletion of ozone would cause increased skin cancer, and the death of some plant species along with the complete extinction of algae (Atmosphere Crisis 4).

Some scientists argue that chloroflourocarbons (CFC s) deplete ozone, but other information contradicts this statement. CFC s are found in fire extinguishers, air conditioners, and more commonly known, aerosol cans. In 1980, Mt. St. Helens erupted, spewing millions of tons of ash and pollutants into the air. It is a proven fact that more CFC s were released into the atmosphere by the volcano in one hour than man has in our entire history (Gribben 41). Mt. St. Helens is no different from any other volcano and this is most likely true with other eruptions.

Experts and scientists have also stated that chlorine gas destroys ozone. This statement is likely true but they seem to wrongly accuse humans for this occurrence. Chlorine gas forms when CFC bonds break in the upper atmosphere, and the chlorine atoms from each CFC molecule bond together to form Cl2 molecules. These chlorine molecules attach to the ozone, disrupting the bonds. This reaction where CFC s produce chlorine gas is the whole reason that CFC s are dangerous. But new data suggests that more chlorine gas is released through sea sprays and volcanoes (42).

A more widely accepted theory is that the hole above Antarctica grows and shrinks in a cycle. This cycle lasts one year and is caused by the polar night. Ozone molecules (O3), from time to time, naturally break their bonds, forming an oxygen molecule (O2), and an oxygen atom (O). Ultraviolet radiation from the sun is needed to re-form the bonds. The polar night last six months. This long period of darkness prevents the ozone from re-forming, causing a larger hole. When the sun finally rises in September, the oxygen bonds back into ozone, and the hole shrinks again (43).

In the winter of 1992, NASA conducted a study of the atmosphere over Antarctica. This study lasted one day. They found a 1.5 parts per billion (ppb) reading of chlorine gas in the atmosphere. This according to NASA, is a potentially dangerous level (Wall Street Journal B5). Knowing that chlorine rates always fluctuate, another team of scientists conducted a study and found only a .5 ppb reading. The controversy of this report and outrage from the public prompted President Bush to call for a new study (B5).

When it comes to global warming, or the greenhouse effect, the general public has been even more frightened. Who can blame them when there are many outrageous and biased reports stating human fault at the warming. Many scientists are also exaggerating the full effect of a warmer climate.

Global warming is a natural phenomenon (25). Earth s climate is always changing, never being constant. Between 1000 and 1400, the world climate was unusually warm. The Vikings from Scandinavia settled Iceland and Greenland, who s climate was found to be very hospitable (83). But after 1400, the world began to cool, and a Little Ice Age developed, which lasted to about 1850 (84). European crops failed, and the American colonies suffered harsh, hungry winters. London, England was often hit by snowstorms during the winter, which Charles Dickens frequently describes. Blizzards in London are a rarity today. Also, cold summers caused the Scandinavian countries, along with Greenland and some areas in Canada to be depopulated. During one winter, Tallahassee, Florida hit -2| F. The cool period ended about 100 years ago and we are still currently in the warming period (83).

Scientists say that the greenhouse effect is in full swing, with average global temperatures rising 2-6| F. Other measurements show that the actual rise in temperatures is about 1| F in the last 100 years (Begley 49). It is also interesting to note that most of the warming in the past century has occurred before 1940, while a majority of made-made emissions and pollutants entered the atmosphere after 1940 (Bender 27). Between 1979-1994, when fossil fuel use was extremely high, the earth showed only a .06| F temperature rise (62).

The sun is dotted by small, cool areas called sunspots. The temperatures in these sunspots is only about 10,000| F, while surrounding areas are close to a million degrees. The sunspots come and go in cycles of about eleven years, but this can vary form nine to thirteen years. It has been observed that the length of the cycle varies directly with the global temperatures. It seems that longer cycles of eleven to thirteen years bring cooler weather, and shorter cycles of nine to eleven years bring on warmer weather (67). Between 1940 and 1970, sunspot cycles were long and also the weather

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