It is a molecule that is made up of three oxygen atoms bonded together, O 3. 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 scientist 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 Cl 2 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 (O 3), from time to time, naturally break their bonds, forming an oxygen molecule (O 2), 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 B 5).
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 (B 5). 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 was cool, but after 1970 the cycles shortened up and the temperatures began to rise (67).
Another source of debate on the severity of global warming is the accuracy of computer climate models. The general circulation models that attempt to mimic the future climate system are not very accurate (Global Warming Update 972). The models that all the scientists boast about and try to scare the population with never seem to agree with each other (973). Such is the case in the 1970’s when the Intergovernmental Panel on Climate Change (IPCC) used their models to predict that the average temperature in the 1980’s would rise by +| F. In 1990, however, satellite measurements, which are extremely accurate, showed only about a.
1| F rise (973). There is also an explanation that the increase in average temperatures is due to only in increase in nighttime low temperatures, not daytime highs (Bender 83). The earth is made up of 75% nitrogen, 20% oxygen, and 5% other. Included in this other is. 02%, not 2%, but. 02% carbon dioxide.
As reported, during the last 100 years, the earth’s average global temperature has increased 1| F. This has all happened when at the same time the carbon dioxide has increased over 50% (39). This should be enough proof to convince one that a significant increase in carbon dioxide has only a small effect, if any, on temperature. Most biologists agree that if there was any significant increase in carbon dioxide, which it seems that there is, the plants would respond by taking in more of the gas, which would produce more oxygen, and, in turn, increase the productivity in plants (83). Also, there is a large amount of evidence supporting the fact that a slightly warmer climate would be beneficial. First, warmer temperatures would enhance evaporation. This increased evaporation would cause more cloud cover (96).
The cloudiness would moderate temperatures during the day, decreasing the likelihood of droughts. The clouds would also act as a blanket at night, which supports the theory mentioned earlier that the increase in average temperatures is caused by warmer nights. Warmer nights would reduce frosts, and increase the growing season. The greatest gain in temperatures would be found in higher latitudes (near the poles), with little or no change in the equatorial tropic area (96). Warmer weather in these cooler regions would mean less harsh weather, fewer early frosts, and generally more rain. This, in turn, would make more arable farmland.
Another little known theory is that global warming would reduce ocean levels. This is due to drier inland areas receiving more rainfall. The precipitation would be soaked into the ground in these drier areas, not draining back into the ocean. The 1| F warmer temperatures has in fact caused more precipitation proven by the Greenland ice cap growing, not melting, in the last 100 years (97).
In short, what would happen if the climate warmed up Judging from past warm periods in history, Western Europe, the Sahara, Australia, and the American Southwest would receive more rainfall. Russia, Western Europe, and interior portions of Canada would see a warm up. It could dry up some what in the Great Plains and the Midwest (96). So we could see corn and soybeans being grown in New Mexico, Spain, and Canada, areas that are now too dry or too cool for such farming. Grasslands could develop in the Sahara and in Arizona, while a desert-like area could form in Kansas, Oklahoma, and Texas. One could hopefully conclude that the environment is not in danger.
The ozone controversy can be summed up by simply stating that it is a natural cycle. The global warming argument is a much more complicated issue with much information for both sides. But one must realize that the earth’s climate is never at a constant. It has always changed and it always will change no matter what humans due. If mankind had to choose between a warmer climate and a cooler climate, we would be better off with being warm.
Atmosphere Crisis. 3 vols. New York: Norton, 1993.
Begley, Sharon. Too Much Hot Air. Newsweek 20 Oct. 1997: 48-50.
Bender, David, ed. Global Warming: Opposing Viewpoints. San Diego: Green haven, 1997.
Global Warming Update. Congressional Quarterly 1 Nov. 1996: 963-80.
Gribben, John. Odds on Ozone. Popular Science Apr. 1995: 41-4.
Is NASA Exaggerating the Threat of Ozone Depletion The Wall Street Journal 3 Apr. 1992, midwest ed.