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THE OZONE LAYER
The Ozone layer is like a thin shield very high in the sky that protects the Earth from the Sun’s harmful radiation; the UV rays. “The Ultra Violet light has shorter wavelengths to the human eye although some insects can see them” ("Mission: Science. "Ultraviolet waves. NASA, 2011. Web. 20 Aug 2012.).
The Sun is the source of ultraviolet radiation, the radiation is divided inUV-A, UV-B and UV-C, these last ones are the most harmful and are the ones that are almost completely absorbed by the atmosphere. UV-B rays are the ones that cause sunburn and the exposure to this rays increases DNA and cellular damage, about 95 percent of the UV-B rays are absorbed by Ozone.
Ozone is a natural gas that is found in two different layers of the atmosphere, one of them is thetroposphere, this is at the Earth’s surface, where we live, ozone in the troposphere is bad because it causes the air to get dirty and it’s not good to breath, Ozone is also found in the stratosphere, which is miles above the Earth’s surface and there is good because it absorbs some of the UV rays as it is mentioned before.("Ozone Layer." Sunwise kids. N.p., 2009. Web. 20 Aug 2012.)
In 1980 scientistbegan finding clues that make them figure out that the ozone layer was going away, which allowed more UV radiation to reach the Earth and by the 1990’s British Scientist discovered a damage to the atmosphere in the Antarctic. Gases such as CFC’s damaged the ozone layer and created a huge hole, dangerous ultraviolet light could pass through that hole and reach the Earth’s surface.Chlorofluorocarbons (CFC’s) are nontoxic and nonflammable chemicals that contain atoms of carbon, chlorine and fluorine, they are used to make aerosol sprays, some blowing agents for foams, solvents and refrigerants.
Refrigerators in the early 1900 used toxic gases as ammonia (NH3), methyl chloride (CH3Cl) and sulfur dioxide (SO2) as refrigerants. After a series of fatal accidents in 1920 caused because methylchloride leaked out of refrigerators, three American corporations: Frigidaire, General Motors and Du Pont collaborated for the search of a less toxic replacement and in 1928 CFC’s where synthesized by Thomas Midgley Jr of General Motors.
CFC’s can be safe to use in a lot of applications and are inert in the lower atmosphere, but they mean a significant reaction in the upper atmosphere orstratosphere as they could be a major source of inorganic chlorine, and some of that chlorine would destroy the ozone in that specific layer.(Welkins, J.. "Chlorofluorocarbons (CFCs)." The Chapman & Hall encyclopedia of Environmental Science. Kluwer Academic, 1999. Web. 20 Aug 2012).
Scientists believe that the increases in skin cancer, plant damage and reduction of plankton in oceans may result fromthat increased UV exposure because of the ozone depletion. In 2006 the hole in the ozone layer was largest than ever with 11 million square miles.
In 1980 a businessman used an antitranspirant to impress his secretary, it didn’t work, and a side effect of sprays in 80’s was that the CFC’s gases inside the can damaged the Ozone layer, in 2007 the same businessman complained about his hair lossdue to years of exposure to unfiltered sun rays directly on his head.
Environmental scientist James Lovelock renowned for his predictions of climate change’s deadly impact on the planet, he admitted that his prediction was alarmist, he is also the one who developed the Gaia theory of earth as a single organism, he said climate change is still happening but not as fast as he said before.
Five yearsago he claimed “before this century is over, billions of us will die and the few remaining people will live in the Arctic where the climate will remain tolerable”, he also said that the problem was that we didn’t know what the environment was doing, they thought they knew 20 years ago because it looked so clear, but it hasn’t happened, “I will not go back on climate change” he said, and...
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