Hey guys, i am not talking about Rahul Dravid- the wall of cricket team of india. i am talking about the hole which is there in the precious ozone layer. The ozone layer is a layer of useful gas called OzoneThe ozone layer resides in the stratosphere and surrounds the entire Earth. the sun is the only source of energy for us. the sun provides with energy. as the two sides of same coin, the sun also radiates harmful radiation. a part of that is the ultra-violate rays or UV rays. again the thought is suitable to this concept. there are three parts of UV_rays. UV-A,UV-B,UV-C. from these the UV-A and UV-C are useful in the formation of ozone. the prime function of ozone layer is to absorve this harmful ray. The hole which is made in the ozone layer above the south pole. Each spring in the stratosphere over Antarctica (Spring in the southern hemisphere is from September through November.), atmospheric ozone is rapidly destroyed by chemical processes.
As winter arrives, a vortex of winds develops around the pole and isolates the polar stratosphere. When temperatures drop below -78°C (-109°F), thin clouds form of ice, nitric acid, and sulphuric acid mixtures. Chemical reactions on the surfaces of ice crystals in the clouds release active forms of CFCs. Ozone depletion begins, and the ozone “hole” appears.
Over the course of two to three months, approximately 50% of the total column amount of ozone in the atmosphere disappears. At some levels, the losses approach 90%. This has come to be called the Antarctic ozone hole.
In spring, temperatures begin to rise, the ice evaporates, and the ozone layer starts to recover.
As winter arrives, a vortex of winds develops around the pole and isolates the polar stratosphere. When temperatures drop below -78°C (-109°F), thin clouds form of ice, nitric acid, and sulphuric acid mixtures. Chemical reactions on the surfaces of ice crystals in the clouds release active forms of CFCs. Ozone depletion begins, and the ozone “hole” appears.
Over the course of two to three months, approximately 50% of the total column amount of ozone in the atmosphere disappears. At some levels, the losses approach 90%. This has come to be called the Antarctic ozone hole.
In spring, temperatures begin to rise, the ice evaporates, and the ozone layer starts to recover.
The ozone hole is defined geographically as the area wherein the total ozone amount is less than 220 Dobson Units. The ozone hole has steadily grown in size (up to 27 million sq. km.) and length of existence (from August through early December) over the past two decades.There is a possibility of depletion of ozone layer as it is reduced by cfc used in refrigerators,spray cans...!!!!!
akshay deoras
