concepts of hazards

• Natural phenomenon


  A physical event that does not affect humans
• Hazardous event

  A natural phenomenon in a populated area
• Natural disaster

  A hazardous event that causes a large number of fatalities or property damage
• If a natural phenomenon occurs in an area where there is no human interest then it is not a hazard
• Human intervention

  Can increase the severity and frequency of a hazard
• Removing the toe of a mountain

  Can cause landslides
• Building new settlements in a volcanic area

  Will cause there to be a natural disaster
• Destroying coral reefs

  Can intensify the storm surges
• Desertification


  A human induced natural hazard
• When the vegetation in an area gets destroyed and leaving the soil damaged
• UN criteria for determining a hazard a disaster

  • A report if 10m or more people dead
  • A report of 100 or more people affected
  • A decoration of a state of emergency by relevant government is made
  • Request by national government for international aid
• The nature and forms of natural hazards

  • Geophysical - main causing factor is geological or geomorphological (earth movement)
  • Atmospheric- main causing factors is an atmospheric process
  • Hydrological- main causing factor is a water process
• Forms of natural hazards

  • Landslide
  • Storms
  • Wildfires
  • Earthquake
  • Coastal flooding
  • Snow storms
  • Volcanoes
  • Droughts
  • Acid rain
  • Tsunami
  • Storm surges
  • Tornadoes
  • Avalanches
  • Desertification
  • Lightning
• All natural hazards

  • Have clear origin and clear impacts
  • Have short warning times
  • Require emergency cost due to scale and intensity
  • Cause damage to properties and life shortly after event
  • Some effects can be felt longer after the event
• Frequency


  How often a disaster occurs
• Duration


  How long the event lasts for
• Temporal spacing


  The pattern of the occurrence of hazard e.g if events are random (volcanoes) or if there is a seasonal pattered (storms or drought)
• Magnitude


  Size of the hazard
• Spatial concentration


  Pattern of distribution of a hazard over an area e.g. ring of fire
• Speed of onset


  Sudden or slower acting natural hazards
• Risk


  Hazard x Vulnerability / Capacity to cope
• Vulnerability


  How prepared is the area e.g. healthcare, resources and supplies, plans and evacuations
• Perceptions of hazards


  • Acceptance
  • Adaptation
  • Dominance
• Wealth and status

  More wealth have more technology to help, more domination. Less wealth so less money more acceptance.
• Education


  More education so can understand the need to respond and the research, adaptation. Less education, acceptance.
• Religion


  More religious then believes it's a act of god, acceptance. Atheist so more adaptation or domination.
• Past experience


  More frequent occurrence is acceptance as it constant. Less frequent occurrence is domination or adaptation.
• Employment


  More employment means more money and funding for research, domination. Less employment means more acceptance.
• Scales of responses

  • Local scale (education, search and rescue)
  • National scale (building defences, infrastructure)
  • International scale (aid, sharing information)
• Changing response as time goes on

  1. Emergency relief in immediate aftermath (saving lives, temporary settlements)

  2. Resolving longer term problems (restoring basic services, repairing infrastructure)

  3. Long term responses (improving quality of life, full rebuild)
• Future of responses

  • Getting easier due to development of technology and interconnectedness
• ADAM


  Automatic disaster analysis and mapping
• ADAM

  • Data collected from many places (e.g. US geological survey)
  • Data available as soon as hazard has occurred
• Fatalism


  Accepting there will be a risk, little prior knowledge, viewpoint in developing countries
• Factors affecting fatalism

  • Lack of funds
  • Lack of information/technology
  • Religious beliefs
• Predictions


  1. Predicting when and where hazard will take place

  2. Hurricane tracking gives time to evacuate
• Adaptation


  • Constant hazards lead to adapted behaviours
  • Tornado alley has tornado shelters
• Factors affecting adaptation

  • Money
  • Technology standards
• Mitigation


  Help reduce or eliminate long term risk to humans and properties
• Mitigation

  • Earthquake resistant buildings