Learn about the ozone layer and its chemical components. Also learn about how the ozone layers gets damaged by human activities on earth.
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Learn About the Ozone Layer From the cameras of the space shuttle Atlantis the distinction between two different environments is apparent. All encompassing is the infinite massive space of vacuum in which humans cannot survive without complicated life support systems and below is the planet earth, home of abundant life and the human species. Changes over the years such as ozone depletion and the greenhouse effect have been detected and recorded by scientists. These are the result of changes taking place in our atmosphere. The ozone is made up of oxygen. However, a regular oxygen molecule is made up of oxygen atoms that are bonded together. Whereas ozone molecules comprise at three oxygen atoms bonded together. In a laboratory, it is possible to construct ozone so that its characteristics can be studied. It can also be made naturally in the upper atmosphere. In its natural form, the ultraviolet from the sun breaks apart the bond in molecular oxygen to form two separate atoms. Ozone is formed when these atoms join with other molecules. Scientist believes that if ozone did not exist, cases of skin cancer and eye cataracts would dramatically increase. Thus, its importance is demonstrated. Sunscreen would serve as a level of protection for humans but animals are still unprotected. Scientific instruments carried in weather balloons, satellites and sounding rockets are showing that ozone levels are decreasing over much of the earth. In Antarctica, ozone levels decreased annually from September to November. The main causes for these dropping levels are the use of chemical compounds, CFCs and the many different oxides of nitrogen. These compounds are broken down in the upper atmosphere into smaller parts. The CFCs give off chlorine atoms whereas the nitrogen oxides turn into nitric oxide. These are then joined by other chemicals containing hydrogen, sulfur and other such atoms. A reaction occurs when these chemicals encounter ozone that breaks away from an atom of oxygen from an ozone molecule. The product of these individual reactions also affects other ozone molecules thus one reaction can spun up a chain reaction that destroys many ozone molecules. These chemicals come from sources like methane formed by agricultural activity, the cattle industry and decaying vegetation in swamps. Nitrogen is released into the atmosphere during lightning storms. Chemical fertilizers that we spray on crops are often nitrogen based and resulting increased release of nitric oxide into the atmosphere. When carbon dioxide blankets the earth and traps heat it is called the greenhouse effect. In a greenhouse, radiation from the sun passes through the translucent roofing completely unhindered yet the heat emanated from the earth is trapped by the glass. The temperature within the greenhouse rises due to this trapped heat. This is exactly what happens on a larger scale to the earth and results in global temperatures rising as carbon dioxide in the atmosphere increases. Volcanoes can cause excess levels of carbon dioxide along with forest fires and many human activities. Millions of tons of carbon dioxide had been pumped into the atmosphere from over a hundred years of fossil fuel consuming machine use. Vegetation cover is also being reduced by forest harvesting and land clearing. This affects the atmosphere adversely as vegetation limits increases in carbon dioxide. The atmosphere is being continually monitored by scientists to determine the presence of gases and trace elements. Ultraviolet radiation from the sun is also being measured. These studies are aimed at better understanding how chemicals in the atmosphere react with the sun’s energy levels and how in turn that affects our environment.
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