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Therefore, appropriate action especially targeted against CFCs should be taken to reduce or stop the many negative effects of ozone depletion (Callan and Thomas 238; Miller 384). The ozone layer is basically ozone present in the stratosphere which protects the earth from ultraviolet radiation from the sun. In the early 1980s, scientists discovered that the ozone layer seemed to become thinner and thinner, till an “ozone hole” the size of North America was revealed over Antarctica. The theory largely accepted by scientists for this “ozone hole” is the presence of CFCs in the atmosphere.
CFCs are a family of odorless chemical compounds which are normally used in air conditioning, refrigeration, insulation, packaging, and as aerosol propellants. Chemists found out that CFCs stay behind in the troposphere because they are chemically unreactive and thus not soluble in water. Although they are heavier than air itself, CFCs can levitate into the stratosphere mostly through convection currents, random drifting, and the violent mixing of air in the troposphere. Once they enter the stratosphere, the CFC molecules separate under the impact of the high-energy ultraviolet radiation, releasing chlorine, fluorine, bromine, and iodine atoms.
These atoms are highly reactive, and so hasten the breakdown of the ozone layer in a repeated chain of chemical reactions. . The thinning of the ozone layer allows more harmful ultraviolet radiation to reach the earth’s surface. Research has proved that exposure of human skin to a certain type of ultraviolet radiation in sunlight is the main cause of basal cell and squamous cell skin cancers. Together, these two forms of cancers make up for ninety five percent of all skin cancers, and are responsible for about 2300 deaths in the United States each year.
Moreover, these ultraviolet radiations increase the intensity of sunburns and cause immune system suppression. Besides this, ozone depletion reduces forest productivity for UV-sensitive tree species, decreases the population of certain aquatic species and surface phytoplankton (and as a result disrupts aquatic food webs), increases eye cataracts in particular species, and cuts down the yield of certain types of crops. What is more, the lessening of the ozone affects air pollution by increasing acid deposition and photochemical smog.
CFCs, on the other hand, act as greenhouse gases and make the earth warmer, thus contributing to global warming (Miller 384, 385). As a result, it is extremely important to keep the level of ozone depletion and the amount of CFCs present in the atmosphere under control. One approach towards the emission of pollutants such as CFCs can be to replace them with other cleaner substances. For example, HFCs and HCFCs can be used in air conditioning equipment and refrigeration instead of CFCs because they have a lower potential of ozone depletion.
The pathways by which these substances are emitted can also be altered to prevent them from entering the atmosphere. Old vehicles mostly use CFCs in air conditioning. Therefore, it is necessary to make sure that such vehicles are serviced by qualified technicians in
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