Tropical cyclones and droughts

Cards (7)

  • Conditions for a tropical cyclone
    1. 26.5 degrees or higher (water temperature)
    2. water has to have a depth of 70m
    3. winds that blow in different directions on the ocean surface
    4. low wind shear
  • Formation of a tropical cyclone
    1. Water evaporates which creates clouds
    2. Warm air rises which creates an area of low pressure and increase surface winds
    3. The tropical cyclone moves west due to easterly winds. The Earth rotation deflects the winds making the storm spin
  • Features of a tropical cyclone
    Eye:
    = 50km
    = no rain or clouds
    = high temps
    = low pressure and light winds
    Eyewall:
    = spiralling rising air
    = strong winds (160km/h)
    = storm clouds and rain
    = low temps
    Spin anticlockwise in the north hemisphere and clockwise in the southern hemisphere
    Last 7-14 days
  • Hazards of tropical rainstorms
    • High winds (250km/h)
    • Intense rainfall
    • Storm surges (sea levels rise drastically)
    • Coastal flooding (result of storm surges)
    • Landslides
  • What is drought?
    Drought is when an region gets below average rainfall for a long period of time]
  • Hazards caused by droughts
    • Depletion of water supplies
    • Food shortages (crops don't get as much water)
    • Soil dries up and plants die
    • Wildfires (vegetation becomes dry)
  • Causes of drought:
    • Changes in atmospheric circulation
    • Climate change causes water to evaporate faster
    • Lack of water stores
    • Intensive farming (draining water)
    • Building dams (can affect areas downstream of the dam)
    • Deforestation