Key Knowledge

• Duration is how long a hazardous event occurs for. This has both secondary and primary impacts on an area.
• Primary/direct impacts are direct consequences of a hazardous event
• Secondary/indirect impacts are impacts that cannot be directly linked to the hazard
• Areal extent is the size of an area affected by a hazardous event
• Magnitude can be measured by:

  • The Richter Scale
  • Modified Mercalli Scale
  • Volcanic Explosivity Index
• Frequency is how often a hazardous event occurs at a certain level, which is also know as RECURRENCE INTERVAL (RI)
• The equation to determine RI is:

  T=N/M
• Frequency and magnitude have an inverse relationship
• Regularity is how those affected by hazards in a space of time lean to cope
• Spatial Concentration is the distribution of types of hazards over a given area
• Hazard is the potential threat to life or property
• Social Impacts of a hazard: loss of life, disease, homelessness, mental health issues
• Economic Impacts of a hazard: loss of tourism, damage to buildings, loss of businesses, countries in debt
• Environmental impacts of a hazard: loss of habitat, sea water flooding, sewage leaks
• A hazard doesn't always equal a natural disaster
• Resilience is the degree to which the population or environment can absorb a hazardous event and has the ability to cope and recover
• Risk is the probability of a hazard occurring
• If unprepared and unknowledgable the risk of a hazard increases
• Risk assessment is the likelihood of harm or damage to occur
• probability of event occuring x severity of the hazard
• Vulnerability is the high risk of exposure to a hazard but also the ability to cope with it
• Factors that amplify vulnerability: economy, lock of funding, climate, population density
• Factors that reduce vulnerability: education, structural integrity, increased expenses on systems
• When evaluating the impact of a hazard/disaster event, you must consider:

  • magnitude- physical
  • duration- physical
  • extent- physical and or human
  • resilience/vulnerability- human
• On what scale are human responses?

  Global, national, local, individual
• The bigger a response, the slower it is
• The Physical aspects that affect response:

  • geographical accessibility of the location/region affected
  • type of hazard
  • topography (forms of the land) of the region affected
  • climate and weather factors
• The Human aspects that affect response:

  • number of people involved or affected
  • degree of community preparedness
  • technological resources
  • scientific understanding and or expertise
  • level of general education and training
  • economic wealth of the region affected
  • quality and quantity of the infrastructure
  • political framework e.g. government competency and organisation
• Modify the loss: framework in which you try and reduce loss of home, livelihood and jobs.

  Examples are to provide insurance and to provide aid
• Modify vulnerability: framework in which you try and decrease the number of people injured or killed.

  Examples are educate to change behaviours to stop hazards becoming disasters, prepare community, predict and warn
• Modify the event: framework in which you try and reduce the impact on buildings using engineering.

  Examples of this are to design buildings that are hazard resistant, land use zoning, retrofit buildings
• Modify the cause: framework in which you try and prevent the hazard altogether

  Example would be to have total environment control but this is only possible for small hazards
• Japan Earthquake Primary: Shaking ground, people falling, trees shaking
• Japan Earthquake Secondary: Tsunami which caused Fukushima, 121,000 buildings fell, flooding, landslide, land subsidence, 6100 injured
• Nevado Del Ruiz Primary: lava, volcanic bombs, pyroclastic flow, ash clouds
• Nevado Del Ruiz Secondary: Lahars caused lava mixing with melting snow, 24 000 dead, $218 billion, 6000 killed by lahars, water contamination caused disease
• The Park model of human response to hazards:

  • Relief- immediate local or global response in the form of aid or expertise
  • Rehabilitation- longer phase lasting weeks or months in which the infrastructure and services are greatly restored
  • Reconstruction- takes months or years to improve quality of life to the same level as it was before the event
• Fatalism is when one realises that there will be losses in a natural disaster and there is very little we can do
• Due to an increase in technology, we can now easily predict hazardous events, these predictions can be communicated quickly which helps reduce the risk of death
• Natural hazards and disasters are inevitable and therefore, we must be able to adapt to them by changing our behaviour, this is cost effective for governments