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The ozone layer



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 in UV-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 the troposphere, 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 scientist began finding clues that make them figure out that the ozone layer was going away, which allowed more UV radiation to reach theEarth 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 methyl chloride 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 or stratosphere 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. KluwerAcademic, 1999. Web. 20 Aug 2012).


Scientists believe that the increases in skin cancer, plant damage and reduction of plankton in oceans may result from that 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 loss due 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 years ago 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 admitted he had been extrapolating too far so it will suggest how people can change their habits to be coordinated with the Earth’s natural systems. Something can be done yet.
There is an international agreement called the “Kyoto protocol” that is linked to the United Nations Framework Convention on Climate Change and it’s major feature is that it sets binding targets for 37 industrialized countries and the European community for reducing greenhouse gas emissions to an average of five percent against 1990 levels in a period of 5 years (2008-2012). It recognizes that the developed countries are the ones that are mainly responsible for the current levels of GHG emissions in the atmosphere that are results of more than 150 years of industrial activity. This protocol was adopted in Kyoto on December 11 of 1997 and entered in to the force on February 16 2005.
Under the protocol, countrie’s actual emissions have to be monitored and they have to keep precise records of trades carried out, this protocol is generally seen as an important step towards a truly global emission reduction regime that will stabilize Green House Gas emissions, it also provides the essential architecture for whatever internationall agreement to be made on the future. By the end of the first commitment period of the KyotoProtocol in 2012 a new segment has to be integrated, an extension of the Kyoto treaty, EU said that it will sign up to the extention up to 2020 it by 2015 all nations agree in a new legal treaty that will come in into force. But many other industrialized nations including US, Japan and Russia said that they wont sign up into any agreement based on Kyoto’s principles although Australia wants to join. All the comments about Australia wanted to get in were welcomed by green groups that said it will give the government political freedom to approve an extension of the Kyoto treaty and in that way with Australia’s help the emissions cut be cut up to five percent by 2020, let’s keep forward more nations joining if they want the planet to survive.
Sources:
https://www.esrl.noaa.gov/gmd/hats/publictn/elkins/cfcs.html
https://www.technologystudent.com/despro_flsh/ozone1.html
https://www.theozonehole.com/cfc.htm
https://www.epa.gov/ozone/science/sc_fact.html
https://www.epa.gov/sunwise/kids/kids_ozone.html
https://missionscience.nasa.gov/ems/10_ultravioletwaves.html
https://www.businessgreen.com/bg/news/2200019/could-australia-sign-up-to-kyoto-extension
https://unfccc.int/kyoto_protocol/items/2830.php/
https://www.dailymail.co.uk/news/article-2134092/Gaia-scientist-James-Lovelock-I-alarmist-climate-change.html







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