Natural Hazards

• Factors that increase hazard risk

  • u rbanisation
  • a griculture
  • c limate change
  • m agnitude
  • p overty
• Distribution of earthquakes


  found in belts along all plate margins. Some found away from margins due to human activity like fracking
• Distribution of volcanoes


  Found in belts along constructive and destructive plate margins (Ring of fire), hotspots like Hawaii
• Temperature of inner core

  5500
• What is inner core made of

  Solid , iron and nickel
• Outer core


  Liquid , iron and nickel
• Mantle


  semi-molten rock called magma, thickest layer
• Slab pull

  • denser plate sinks back into mantle under influence of gravity
  • pulls rest of plate along behind it
• Ridge push

  • Magma rises as plates move apart
  • Magma cools to form new plate material
  • As it cools it becomes denser and slides down away from the ridge
  • This causes tectonic plates to move away from eachothe
• How to reduce effects of tectonic hazards

  • Monitoring - e.g. satellite energy
  • Predicting - past events
  • Planning - drills, evacuation plans
  • Protecting - earthquake resistant buildings, tsunami walls
• Distribution of tropical storms

  • between 5 and 30 N and S of equator, usually between tropic of cancer and capricorn where oceans are warmest
• Causes of tropical storms

  • Warm oceans (over 27)
  • Coriolis effect (earth's spin)
  • Low air pressure (warm air rises to take evaporated water with it)
  • Condensation
  • Clouds
  • Wind
• Features of a tropical storm

  • Eye (cold air sinks, weather is calmest, no rain)
  • Eyewall (winds are strong and rain is heavy)
• Insolation


  Amount of solar radiation an area recieves over time
• How is heat moved around the atmosphere

  Rises until it cools and then sinks in a ciculation, it repeats. When heat rises there is low pressure and when it sinks there is high pressure