Ozone Layer Destruction
Role of CFCs in ozone depletion
The destruction of the ozone is attributed to Chlorofluorocarbons, which consists of mainly three atoms Chlorine, Carbon and Fluorine, which are the main cause of ozone destruction (Stanley, 2000). Besides, some free radical catalysts mainly Nitric oxide radical (NO-) hydroxyl radical (OH-), atomic Chlorine (Cl) and Bromine (Br) are responsible for depletion of the ozone. All of these atoms and radicals have can be naturally and artificially made. Presently, the hydroxyl and Nitric oxide radicals occur naturally at the stratosphere. Chlorine and Bromine are as a result of human activity mainly found in stable organic compounds particularly Chlorofluorocarbons (CFCs). When the CFCs find their way to the atmosphere without being destroyed as a result of their low reactivity, the Bromine and Chlorine are detached from the main compounds by activity of ultraviolent light i.e. hV (h-Plancks constant and V-frequency of the electromagnetic radiation)CFCl3 hVC FCl2 Cl
The free Bromine and Chlorine atoms are responsible for destruction of ozone molecules through different catalytic processes. The most common reaction of Bromine or Chlorine with the Ozone involves the BrCl atoms taking away one oxygen atom from Ozone forming ClOBrO and leaving an ordinary oxygen molecule (Stanley, 2000). The BrCl monoxides can also react with an ozone molecule forming another chlorinebromine atom and two other molecules of oxygen. The equations below represent these reactions
Chlorine Ozone Chlorideoxide Oxygen gas
Cl O3 ClO O2
Chloride oxide Ozone Chlorine Oxygen gas
ClO O3 Cl 2O2
This leads to decrease in amount and concentration of Ozone. One chlorine atom is capable of reacting with 100,000 ozone molecules, which makes the ozone more vulnerable considering the rate of CFC release to the atmosphere.
Sources and uses of CFCs
Chlorofluorocarbons are widely used in most applications in life due to their stable, non-combustive and harmless properties. They are used as cleansing agents in electronic industry, coolant for air conditioners, foaming agents for making insulators among other numerous uses (Pahari and Chauhan, 2006). Due to their role in destruction of the ozone layer, CFCs production was completely banned by 1995. There is need to ensure proper use of CFCs currently used in appliances to ensure their effects are minimal.
Hydrochlorofluorocarbons (HCFCs) are another important agent of ozone destruction but their effects are less powerful as compared to that of CFCs. However, they must also, be contained to reduce Ozone destruction.
Consequences of ozone destruction
The destruction of ozone layer permits the penetration of the harmful ultraviolent radiation direct to the earth surface. Stanley (2000) outlines the following effects of UV on human life including
Increased incidence of skin cancer
Increased sun burning and cataracts
Adverse effects on animals and crops
Threatening sea life due to reduction in planktons growth in oceans
Repressed immune systems in living organism, hence increased diseases
Cooling of the stratosphere of the earth and finally but not the least
Global warming
Global concern on ozone destruction
The consequences of global warming are adverse and are being experienced in various parts of the world. Ozone destruction can be reduced through reduction of CFCs. The long-term solution however can only be met through phasing out the use of CFCs by adopting green strategies to save the ozone (Mathew, 2008). Various innovations to reduce production of green house gases that are responsible for destruction of the ozone have been adopted. Developed countries have particularly opted for alternative energy sources such as solar energy that does not produce CFCs.
Ozone destruction is a global concern and awareness regarding effects of its destruction should be increased as well as promoting CFC reduction strategies. According to United Nations Environmental Program scientific report on environmental impact and technological economic assessment in 1994, the amount of chlorine and bromine was predicted to peak in the troposphere in 1994. It would peak 3-5 years later in the stratosphere and later diminish as long as all the signatory countries remain conscious of the 1992 revised Montreal Protocol (Stephen, Madhava and Lani, 2004). Further, the reduction in ozone depletion was predicted to continue in the remaining years of the 20th century. With other factors being unchanged, the ozone is expected to begin to restore in the early years of the 21st century and by 2045, the Antarctic hole would have disappeared. The most recent conference in Copenhagen was also an effort to reduce ozone destructions by country members. However, the predictions made are far from reality as the efforts to contain CFCs are faced by different challenges especially in the developing countries.
Ozone layer is the layer that lies between 15-20 kilometers from the earth surface, which protects the earth from harmful ultraviolent radiation from the sun. Its destruction is caused by HCFs and HCFCs that are mainly produced through human activities. The consequences of ozone destruction are fatal with global warming being the most evident result. Global concerns over ozone depletion are in an increase with stakeholders advocating for green strategies to reduce production of CFCs. Various environmental bodies are putting pressure on manufacturers to reduce the use of CFCs and HCFCs for the sake of the ozone layer. However, this is being faced by various challenges including overpopulation, industrialization, urbanization and increased exploitation of natural resources especially fossil fuel.
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