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Global Warming

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Global Warming

  2. Global Warming <ul><li>an average increase in the temperature of the atmosphere near the Earth ’ s surface and in the troposphere1, which can contribute to changes in global climate patterns </li></ul>
  3. Causes <ul><li>Burning of fossil fuels (Coal/Crude oil) </li></ul><ul><ul><li>Power plants  generate electricity </li></ul></ul><ul><ul><li>Transportation-----fuels for transports (E.g. LPG, </li></ul></ul><ul><ul><li>kerosene, fuel oil) </li></ul></ul><ul><ul><li>Industrial processes (E.g. manufacture of </li></ul></ul><ul><ul><li>cement, steel, aluminium) </li></ul></ul>
  4. Causes <ul><li>Other greenhouse gases emission </li></ul><ul><ul><li>Agriculture </li></ul></ul><ul><ul><li>Forestry </li></ul></ul><ul><ul><li>Other land uses </li></ul></ul><ul><ul><li>Waste management </li></ul></ul>
  5. Besides carbon dioxide, other gases such as methane, chlorofluorocarbons, nitrogen oxides and ozone also contribute to the greenhouse effect. Example : Using natural gas to cook CH 4 + 2O 2  CO 2 + 2H 2 O
  6. Greenhouse gases in the atmosphere ↓ Some infrared radiation is trapped ↓ Greenhouse effect Serious greenhouse effect Global Warming
  7. How serious the problem is?...
  8. Increase in greenhouse gases <ul><li>Concentration of greenhouse gases in the atmosphere is highly increasing by human activities </li></ul><ul><ul><li>-> Leads to the increasing seriousness of global warming </li></ul></ul>
  10. Global surface temperatures <ul><ul><li>increased about 0.6°C/century since the late19th century </li></ul></ul><ul><ul><li>increased to 2°C/century over the past 25 years </li></ul></ul>
  11. Increase in Global temperatures
  12. Temperature difference between different parts of atmosphere <ul><li>troposphere temperatures (the lowest 8 kilometers of the Earth's atmosphere) collected since 1979 also indicate warming </li></ul><ul><li>Cooling effect in higher parts of the atmosphere: stratospheric temperatures have been decreasing </li></ul>
  15. NOT globally uniform warming <ul><li>Warming parts: </li></ul><ul><ul><li>North America </li></ul></ul><ul><ul><li>Eurasia </li></ul></ul><ul><li>Cooling parts: </li></ul><ul><ul><li>parts of the southeastern U.S. </li></ul></ul>
  17. Increasing temperature extremes <ul><li>Regions that have temperatures (1-3°C) warmer than the average: </li></ul><ul><ul><li>United States </li></ul></ul><ul><ul><li>Most of the Europe </li></ul></ul><ul><li>Regions that have temperatures (1-3°C) cooler than the average: </li></ul><ul><ul><li>Australia </li></ul></ul>
  18. Regional Temperatures
  19. Sea level rising <ul><li>rising at an average rate of 1 - 2 mm/year over the past 100 years </li></ul>
  20. Environmental and Human Effects
  22. Direct Temperature Effects <ul><li>Increase in average temperature </li></ul><ul><li>More extreme heat waves during the summer; Less extreme cold spells during the winter </li></ul><ul><li>Harmful to those with heart problems, asthma, the elderly, the very young and the homeless </li></ul>
  23. Extreme Events <ul><li>Extreme Events: </li></ul><ul><li>Heat waves; Cold waves; Storms; Floods and Droughts </li></ul><ul><li>Global warming </li></ul><ul><li>An increase in the frequency of extreme events </li></ul><ul><li>More event-related deaths, injuries, infectious diseases, and stress-related disorders </li></ul>
  24. Climate-sensitive diseases <ul><li>Increase the risk of some infectious diseases </li></ul><ul><ul><li>[particularly that appear in warm areas; are spread by mosquitoes and other insects] </li></ul></ul><ul><ul><li>E.g. Malaria, dengue fever, yellow fever, encephalitis </li></ul></ul><ul><li>Algal blooms occur more frequently as temperatures warm (particularly in areas with polluted waters) </li></ul><ul><li>Diseases (e.g. cholera) accompanying algal blooms become more frequent </li></ul>
  25. Air Quality <ul><li>An increase in the concentration of ground-level ozone </li></ul><ul><li>Damage lung tissue </li></ul><ul><li>Harmful for those with asthma and other chronic lung diseases </li></ul>
  26. Food supply <ul><li>Rising temperatures and variable precipitation </li></ul><ul><li>Decrease the production of staple foods in many of the poorest regions </li></ul><ul><li>Increasing risks of malnutrition </li></ul>
  27. Population displacement <ul><li>Rising sea levels </li></ul><ul><li>Increase the risk of coastal flooding </li></ul><ul><li>(Necessitate population displacement) </li></ul><ul><li>More than half of the world's population now lives within 60km of the sea. </li></ul><ul><li>Most vulnerable regions: Nile delta in Egypt, the Ganges-Brahmaputra delta in Bangladesh, many small islands, such as the Maldives, the Marshall Islands and Tuvalu. </li></ul>
  28. UV Exposure (Australia) <ul><li>Skin Cancer    </li></ul><ul><ul><li>an abnormal growth of skin tissues. </li></ul></ul><ul><li>Premature aging </li></ul><ul><ul><li>make the skin thick, wrinkled, and leathery   </li></ul></ul><ul><li>Cataracts   </li></ul><ul><ul><li>No longer have transparent lenses in their eyes </li></ul></ul>
  29. UV Exposure (Australia) <ul><li>Other Eye Damages </li></ul><ul><ul><li>Skin cancer around the eyes </li></ul></ul><ul><ul><li>Degeneration of the yellow spot </li></ul></ul><ul><li>Suppression of Immunity    </li></ul><ul><ul><li>Overexposure to UV radiation  suppress proper functioning of the body's immune system and natural defenses of skin </li></ul></ul><ul><ul><li>UV-B radiation weakens the immune system  increases the chance of infection and disease </li></ul></ul>
  30. Measures on controlling the problem <ul><li>Government </li></ul><ul><li>* set some laws to limit the amount of pollutants produced by factories </li></ul><ul><li>* develop the skills of using renewable fuels , e.g. solar energy, wind energy </li></ul>
  31. <ul><li>* encourage the factories to replace fossil fuels by renewable fuels, which would not cause environmental pollution </li></ul><ul><li>* carry out energy saving scheme -> reduce the pollution produced by burning fossil fuels </li></ul><ul><li>* build more plants -> reduce the pollutants e.g. CO 2 </li></ul>Measures on controlling the problem
  32. Measures on controlling the problem <ul><li>Citizens </li></ul><ul><li>* reduce the use of plastic bags -> as burning plastic emit CH4 </li></ul><ul><li>* recycle the resources, e.g. plastic </li></ul><ul><li>* reduce the use of sprays -> as CFCs would be emitted out </li></ul>
  33. Measures on controlling the problem <ul><li>* reduce the use of air-conditioner, which will emit CFCs </li></ul><ul><li>* use public transportation instead of private cars -> reduce the pollutants emitted by cars </li></ul>
  34. Sources <ul><li>http://www.who.int/globalchange/climate/en/ </li></ul><ul><li>http://resources.emb.gov.hk/envir-ed/text/globalissue/e_m2_2_6.htm </li></ul><ul><li>http://epa.gov/climatechange/effects/index.html </li></ul><ul><li>http://www.tchps.edu.hk/greenweb/greenMaindGMsg5.htm </li></ul><ul><li>http://www.ncdc.noaa.gov/oa/climate/globalwarming.html </li></ul>
  35. THE END