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Ozone Layer Depletion

Ozone Layer Depletion. By jyoti awana. Contents. What is Ozone layer Ozone destruction Causes of Ozone depletion Steps in ozone depletion Effects of UV radiations on How to stop ozone depletion Initiatives taken to protect Ozone depletion conclusion. The earths atmosphere.

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Ozone Layer Depletion

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  1. Ozone Layer Depletion By jyotiawana

  2. Contents • What is Ozone layer • Ozone destruction • Causes of Ozone depletion • Steps in ozone depletion • Effects of UV radiations on • How to stop ozone depletion • Initiatives taken to protect Ozone depletion • conclusion

  3. The earths atmosphere • This is the upper limit of our atmosphere. • A layer is also where the space shuttle orbits. • Meteors or rock fragments burn up in it. • Many jet aircrafts fly in it, because it is very stable. • Also, the ozone layer absorbs harmful rays from the Sun. •  The first layer above the surface and contains half of the Earth's atmosphere.

  4. What is Ozone layer • Ozone is a triatomic form of oxygen (O3) found in Earth’s upper and lower atmosphere. • The ozone layer, situated in the stratosphere about 15 to 30 km above the earth's surface. • Ozone protects living organisms by absorbing harmful ultraviolet radiation (UVB) from the sun. • The ozone layer is being destroyed by CFCs and other substances. • Ozone depletion progressing globally except in the tropical zone. www.epcc.pref.osaka.jp/apec/ eng/earth/ozone_layer_depletion/susumu.html

  5. Ozone Depletion • Ozone Depletion; Destruction of the stratospheric ozone layer. This destruction of ozone is caused by the breakdown of certain chlorine and/or bromine containing compounds (chlorofluorocarbons or halons), which break down when they reach the stratosphere and then catalytically destroy ozone molecules. A worrying rate of ozone depletion is found above the Arctic. Stratospheric clouds in the Arctic

  6. Ozone Depletion • Human actions can change the natural state of our climate: • The world community works together in a targetted way, global environmental problems can be effective. • Cfc's are just one class of chemical substance that depletes the ozone layer, but they are the most important one. Ozone formation

  7. Causes of Ozone Depletion

  8. Manufactured Chemicals

  9. Causes of Ozone Depletion • Increase in the level of free radicals such as hydroxyl radicals, nitric oxide radicals and atomic chlorine and bromine. • The most important compound, which accounts for almost 80% of the total depletion of ozone in the stratosphere are chlorofluorocarbons (CFC). refrigerants& propellants

  10. Causes of Ozone Depletion • Other chemicals that damage the ozone layer include; • methyl bromide (used as a pesticide),  • halons (used in fire extinguishers), • methyl chloroform (used as a solvent in industrial processes for essential applications). • Methyl bromide and halons are broken apart, they release bromine atoms. • which are 60 times more destructive to ozone molecules than chlorine atoms.

  11. The Principal Steps in Stratospheric Ozone Depletion Caused by Humans

  12. Effects of ozone depletion

  13. Effects of ozone depletion • Temperature changes and rainfall failures on earth • Climate change • Crop and forest damage • Less ocean plankton • Less fish harvest • Infections and skin diseases on animals • Reduction in plants chlorophyll, marine ecosystem disturbance & microorganisms may get harmed as well

  14. UV-B Effects on Humans

  15. Effects on humans • Skin cancer. • eye disorders (blindness). • Immune system damage. • Premature aging (photo aging) of the skin (different from normal chronological aging). • Sunburn • Sun damaged skin • Cataracts • Fair people will be at greater • Respiratory illness and heart problems

  16. malignant Non-malignant Effects on Human Health www.ldeo.columbia.edu/.../ lectures/ozone_health/

  17. Skin Protection • Protect the skin against the solar radiation using skin creams with SPF • The greater the numerical value of the SPF the greater the protection • Use lip balm with SPF • Cover up

  18. Protection • Sunglasses with 100% UV block • Wrap around sunglasses • Eye protection for children • Hats

  19. How to stop it • Stop pollution • Raise awareness • Plant more trees • Use public transport • Use renewable sources

  20. Contd.. • National and international conferences should be held to discuss on this issue • Framing of strict laws should be given top priority. • Use of alternative technologies is to be implemented. • Modern fridges and AC should be used that do not emit CFCs. • Aerosols free of CFCs must be only used. Natural fertilizers should be used.

  21. Initiatives taken to protect the Ozone layer • Montreal Protocol (adopted in 1987) – panel of experts was formed to investigate substances responsible for hole formation • Established policies that prevent future use of certain types of chemicals • Ending the production, import and use of ozone-depleting substances (ODS), often ahead of the Montreal Protocol schedule • Identifying safe alternatives through the Significant New Alternatives Policy (SNAP) program

  22. Conclusion • Most ozone depletion is the result of human activities • Making small changes in our habits can make a huge difference in our future • As you sow so shall you reap

  23. Reference • http://www.weatherquestions.com/What_is_the_ozone_layer.htm • http://environment.nationalgeographic.com/environment/global-warming/ozone-depletion-overview/ • http://www.patrickbrown.org/ • http://www.teachmefinance.com/Scientific_Terms/Ozone_Depletion.html#ixzz1pIchieF0 • http://news.nationalgeographic.com/news/2010/01/100127-ozone-hole-global-warming/ • http://earthobservatory.nasa.gov/Features/UVB/printall.php • http://www.windows2universe.org/earth/Atmosphere/troposphere.html

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