Desertification

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Desertification

  1. 2. Mid 1980's 2004
  2. 5. Desertification This means turning land into desert. Approximately one-third of Earth's land surface is desert
  3. 6. A satellite image of the Sahara , the world's largest hot desert and second largest desert after Antarctica . A desert is an area receiving less than 10 inches of precipitation annually.
  4. 7. Great Basin Sahara Kalahari Great Victorian Gobi Arabian Atacama Antarctica
  5. 8. Where is the Sahel The Sahel lays to the South of the Sahara Desert and extends across most of Africa. It includes Ethiopia (8) (2), Sudan (37), Chad (7), Niger (1), Somalia (?)
  6. 9. <ul><li>Rainfall – This is confined to just one or two months of the year, but the length of the rainy season is unreliable. </li></ul><ul><li>Drought has a devastating effect because: </li></ul><ul><ul><li>There is less food for people to eat </li></ul></ul><ul><ul><li>There is no rainfall </li></ul></ul><ul><ul><li>Means fewer crops </li></ul></ul><ul><ul><li>1000’s of people are affected ( High pop and birth rates) </li></ul></ul><ul><ul><li>People in danger of dying. </li></ul></ul>
  7. 11. Causes of desertification in the Sahel <ul><li>Climate change </li></ul><ul><li>Decrease in rainfall </li></ul><ul><li>Global warming </li></ul><ul><li>2) Population Growth </li></ul><ul><li>Deforestation more land needed wood for fuel </li></ul><ul><li>Overgrazing more cattle, camels + goats </li></ul>
  8. 12. <ul><li>Rainfall </li></ul><ul><ul><li>Rivers and water holes dry up </li></ul></ul><ul><ul><li>Water table falls </li></ul></ul><ul><ul><li>Vegetation dies </li></ul></ul><ul><li>B) Temperature </li></ul><ul><ul><li>warmer due to global warming </li></ul></ul><ul><ul><li>increase in evaporation + transpiration </li></ul></ul><ul><ul><li>reduce condensation = less rainfall </li></ul></ul>
  9. 13. DRIER THAN USUAL WETTER THAN USUAL

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