Importance Of Troposphere

The atmosphere surrounds the Earth as a thin, about a 100 km thick layer and it consists of 78% N2(Nitrogen), 21% O2(Oxygen), 1% Ar(Argon) and 0.0.39%CO2(Carbon Dioxide). The atmosphere has a number of different layers and each of those layers have different properties. Changes in weather, clouds, rain and wind are formed in the lower atmosphere, 10 to 15 km thick layer known as Troposphere. Although troposphere is deeper in tropical regions, reaching up to 20 km, however in polar regions it can be as shallow as 7km during winter. Troposphere is 90 per cent of the total mass of the atmosphere, and nearly all of the water vapor and this is due to the processes of transpiration and evaporation. As the altitude in the troposphere increases, the temperature decreases by about 6.5 ° C per kilometer increase in altitude. The upper limit of the troposphere is the coldest and it ends at a point called “tropopause”, which is where the upper atmosphere, also known as “stratosphere” begins. The stratosphere, which extends about 50 km from where troposphere ends, is stratified in temperature and lower layers are cooler whilst temperature increases in the layers higher up. The reason why stratosphere is layered in temperature is because ozone (O3) there absorbs Ultraviolet C energy waves and high energy Ultraviolet B from the sun and its broken down in to diatomic oxygen(O2) and atomic oxygen(O). Therefore, The Stratospheric ozone layer protects the plants and animals of carcinogenic and lethal amounts of sun exposure. Although about 10% of the mass of the atmosphere is located in the stratosphere, the air is very thin. The upper region of the atmosphere is known as the Ionosphere and it begins at approximately 85km altitude and stretches ...

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...bons which produce free radicals of chloride from UV light. Chloride free radicals interact with ozone layer O3 to break the ozone layer down: CL-CL –> CL. Chloride from CFC form free radicals when UV light interacts with them: CL. + O3 –> CLO + O2. Chloride free radical interacts with ozone to produce O2 free radical: O-O-> O. Oxygen free radical produced by UV light: O. –>O3 – O2 + O2. Oxygen radical also attacks the ozone layer to produce more oxygen radicals.

In 2009, NASA released a computer simulation of what would have happened if the use of CFCs had not been limited .The simulation of the two-thirds of the ozone layer would be destroyed by the year 2065 at the latest and, therefore, the country entering the ultra-violet radiation amount should be increased 650 per cent. Ultraviolet radiation would have caused significant damage to all terrestrial life.