Geography

• Natural Hazard


  A natural process which could cause death, injury or disruption to humans, or destroy property and possessions
• Natural Disaster


  A natural hazard that has actually happened
• Extreme events which do not pose any threat to human activity are not counted as hazards (e.g. a drought in an uninhabited desert or an avalanche in Antarctica)
• Two Main Types of Natural Hazard

  • Geological Hazards
  • Meteorological Hazards
• Geological Hazards


  • Caused by land and tectonic processes
  • Include volcanoes and earthquakes, landslides and avalanches
• Meteorological Hazards


  • Caused by weather and climate
  • Examples include tropical storms and other extreme weather (e.g. heatwaves and cold spells)
• Hazard Risk


  The probability of people being affected by a hazard in a particular area
• Factors Affecting Hazard Risk


  • Vulnerability
  • Capacity to Cope
  • Type
  • Frequency
  • Magnitude
• Vulnerability


  The more people that are in an area exposed to natural hazards, the greater the probability they will be affected by a natural hazard
• Vulnerable Areas


  • High population density on a flood plain (e.g. much of Bangladesh)
  • City at the base of a volcano (e.g. Naples, Italy)
• Capacity to Cope


  The better a population can cope with an extreme event, the lower the risk of them being severely affected
• Coping Capacity


  • Higher income countries (HICs) can afford to build flood defences and evacuate people
• Type of Hazard


  • The risk from some hazards is greater than others
  • Tropical storms can be predicted and monitored, giving people time to evacuate
  • Earthquakes happen very suddenly, with no warning, so it's much harder to protect people
• Frequency


  • Natural hazards that occur more often may carry a higher risk
• Magnitude


  • More severe natural hazards tend to have the greatest effects (e.g. a magnitude 9 earthquake in Japan in 2011 killed over 15,000 people, whereas a magnitude 6 earthquake in L'Aquila, Italy in 2009 killed under 300 people)
• Primary Effects of Natural Disasters


  • Buildings and roads are destroyed
  • People are injured or killed
  • Crops and water supplies can be damaged or contaminated
  • Electricity cables, gas pipes and communication networks can be damaged, cutting off supplies
• Secondary Effects of Natural Disasters


  • The initial hazard can trigger other hazards (e.g. earthquakes can trigger tsunamis)
  • Aid and emergency vehicles can't get through because of blocked roads or bridges
  • Shortage of clean water and lack of proper sanitation makes it easier for disease to spread
  • Food shortages can occur if crops are damaged, livestock are killed or supply lines are blocked
  • The country's economy can be weakened - damage to businesses can cause unemployment, and the reconstruction process can be very expensive
• Immediate Responses to Natural Disasters


  • Evacuate people (before the hazard occurs if possible)
  • Treat the injured and rescue anyone cut off by damage to roads or bridges
  • Recover dead bodies to prevent disease spreading
  • Provide temporary supplies of electricity and gas if regular supplies have been damaged
  • Provide food, drink and shelter to people without homes
  • Foreign governments or charities may send aid workers, supplies or financial donations
• Long-Term Responses to Natural Disasters


  • Repair homes or rehouse people who have lost their homes
  • Repair or rebuild buildings, roads, railways and bridges
  • Reconnect broken electricity, water, gas and communication connections
  • Improve forecasting, monitoring and evacuation plans
  • Improve building regulations so that buildings can withstand similar hazards in the future
  • Boost economic recovery (e.g. by promoting tourism)
• Wind turbines generate electricity from kinetic energy produced by moving air.