Hazards Extra notes

• Geophysical hazards


  • Earthquakes
  • Volcanic eruptions
  • Landslides
  • Tsunamis
  • Seismic hazards
• Atmospheric hazards

  • Tropical cyclones
  • Storms
  • Droughts
  • Tornadoes
• Hydrological hazards

  • Floods
  • Avalanche
• Disaster


  When hazards actually seriously affect humans
• Risk

  The likelihood that humans will be seriously affected by a hazard
• Vulnerability

  How susceptible a population is to the damage caused by a hazard
• Hazard


  Something that has a potential threat to human life or property
• Natural hazards

  Caused by natural processes, e.g. a lava flow from a volcanic eruption
• Reasons why people perceive hazards differently

  • Religion
  • Wealth
  • Education
  • Past Experience
  • Personality
• The Park Model

  1. Pre disaster

  2. Disruption/ Eruption

  3. Relief

  4. Rehabilitation

  5. Reconciliation
• Advantages of Park Model

  • Good to comparing and contrasting with other events
  • It is versatile and can be applied to a number of hazards
  • Useful for pinpointing the different response needed at a particular point in time
  • A model is just what it saying, an ideal against which to compare and critique reality
• Disadvantages of Park Model

  • Temporal Scale may be different for countries depending on the nature of the event
  • It is not goods at showing quantitative data and therefore it is difficult to comparisons
  • Does not critically examine the fact that some countries are in need of more help outside than others
  • Does Not refer to the magnitude and frequency
• Hazard Management Cycle

  1. Mitigation

  2. Preparedness

  3. Response

  4. Recovery
• Inner core

  Solid ball contained lots of iron and nickel
• Outer core

  Semi molten and also contains iron and nickel
• Mantle

  Made of silicate rocks and can be rigid
• Asthenosphere


  Semi molten
• Lithosphere

  The rigid top part of the mantle and the crust together
• The temperature of the inner core is about 6000 degrees
• The temperature of the mantle is around 1000-3500
• Heat comes from internal energy and some come forms radioactive decay such as uranium
• Continental Crust

  Thicker (30-70 km)
• Oceanic crust

  Thinner (6-10km)
• Mantle

  Semi-molten body of rock between the earth's crust
• Asthenosphere

  Upper part of the mantle
• Core

  Central part of the earth, solid at the centre and more liquid further away
• Risk

  Probability of a hazard happening and creating a loss of lives and/or livelihoods
• Vulnerability

  Risk of exposure to hazards combined with an inability to cope with them
• Resilience

  Degree to which a population or environment can absorb a hazardous event and stay organised and functioning
• How to cope

  1. Have emergency evacuation, rescue and relief systems in place

  2. Helping each other to reduce the numbers affected

  3. Having a hazard-resistant design or land-use planning to reduce the numbers at risk
• Social impacts

  • Deaths
  • Injust
  • Wider health impacts
• Economic impacts

  • Loss of property
  • Loss of business
  • Loss of infrastructure
  • Loss of opportunities
• Formation of Island Arcs

  1. Descending plate melts and material rises towards the source as plutons of magma

  2. These reach the surface and form volcanoes which may erupt offshore
• Young fold mountains


  Between 10 and 25 million years old, form when plates move together and sediment in the sea is pushed up into folds between them
• Deep sea trenches

  Form when a continental plate subducts underneath a continental plate
• Ocean ridges

  Form when two oceanic plates are pulling apart, as pressure is reduced the semi-molten magma of the mantle melts and rises up into the gap between the plates
• Rift Valley

  Forms when two continental plates are pulling apart, as the crust thins it is heated and bulges, forming cracks, and an area of crust drops down between parallel faults
• Inequality of access to education, housing, healthcare and income are root causes of hazards because they influence vulnerability and resilience
• This inequality is seen in the PAR model
• The HDI (Human Development Index) measures this inequality