Hazards

• How does prevention affect seismic hazards?

  • cannot be prevented,
  • liquefaction of soils can be prevented through soil stabilisation,
  • avalanches can be prevented through controlled explosions.
• What is adaptation in a volcanic hazard?

  • move away from area at risk,
  • capitalise on opportunities such as encouraging tourism,
  • change profession so it is less likely to be affected by volcanic hazards.
• What is mitigation in a volcanic hazard?

  • direct intervention to the volcano,
  • strengthening buildings that are at risk of mudflows,
  • evacuation and exclusion zones.
• What is prepared for volcanic hazards?

  • monitoring increasing,
  • education on volcanoes in areas of risk,
  • evacuation procedures planned,
  • training response teams.
• What is prevention to volcanic hazards?

  • cannot be prevented,
  • not allowing people near volcanic hazards.
• What are some secondary effects of a seismic hazard?

  • radioactive materials leaked from power plants,
  • saltwater from freshwater ecosystems,
  • soil salinisation,
  • economic decline,
  • high cost of rebuilding,
  • gas pipes rupture,
  • tsunamis which lead to damaging flooding,
  • political unrest from food shortages,
  • borrowing money for international aid,
  • looting.
• What are some primary effects of seismic hazards?

  • earthquakes can cause fault lines,
  • liquefaction,
  • businesses destroyed,
  • buildings collapse,
  • government buildings destroyed.
• What are some hazards caused by seismic events?

  • shockwaves- pressure built is stored as potential energy, then transferred into kinetic energy when there is too much,
  • tsunamis,
  • liquefaction,
  • landslides and avalanches.
• What are the secondary effects of a volcano?

  • water acidified,
  • volcanic gases contribute to greenhouse effect,
  • jobs lost,
  • profit from tourism industry,
  • fires,
  • mudflows or floods,
  • trauma,
  • homelessness,
  • conflicts concerning government response.
• What are the primary effects of a volcano?

  • ecosystems are damaged,
  • wildlife is killed,
  • businesses destroyed,
  • people killed,
  • homes destroyed,
  • government buildings and areas destroyed.
• What is the VEI?

  • Volcanic Explosivity Index,
  • more powerful= more explosive,
  • high magnitude eruptions= explosive
• What are some volcanic hazards?

  • lava flows- flow depends on viscosity, viscous= slow and in explosive eruptions,
  • lahars- mudflows, caused by melting ice at high latitudes,
  • tephra- rock ejected by a volcano,
  • toxic gases- released during eruptions,
  • acid rain- caused when gases such as sulfur dioxide,
  • pyroclastic flows- clouds of burning ash, fast speeds (average 40mph, max 430mph)
• What are hot spots?

  • areas of volcanic activity that are not related to plate boundaries,
  • hot magma plumes from the mantle rise and burns through weaker parts of the crust,
  • can cause volcanoes and islands,
  • plume stays in same place, but plates continue to move, which can cause a chain of islands.
• Explain conservative plate boundaries.

  • plates slide past each other- diff directions and diff speeds,
  • can cause earthquakes.
• Explain destructive plate boundaries.

  • push towards each other,
  • continental/ oceanic- o subducts below c, can cause earthquakes, fold mountains, volcanoes,
  • oceanic/ oceanic- heavier plate subducts, can cause ocean trenches, island arcs, earthquakes, volcanoes,
  • continental/ continental- both are not dense so lots of pressure builds, can cause fold mountains, earthquakes.
• What is the plate tectonic theory?

  • plates that move due to the convection currents in the asthenosphere,
  • Convection currents are caused when the less dense magma rises, cools, then sinks
• What are the four stages of the Hazard Management Cycle?

  • preparedness,
  • response,
  • recovery,
  • mitigation.
• The Hazard Management Cycle outlines the stages of responding to events.
• What does Stage 3 in The Park Model show?

  • restoring the area,
  • area back to normal,
  • infrastructure rebuilt,
  • mitigation efforts for future event,
  • weeks- years.
• What does Stage 2 in The Park Model show?

  • services begin to be restored,
  • temporary shelters and hospitals set up,
  • food and water distributed,
  • coordinated foreign aid,
  • days- weeks.
• What does Stage 1 in The Park Model show?

  • immediate local response,
  • immediate appeal for foreign aid,
  • hours- days.
• What does The Park Model's lines show?

  • the steepness= how quickly an area deteriorates and recovers,
  • the depth= the scale of the disaster.
• The Park Model is a graphical representation of human responses to hazards.
• How does the level of development affect human responses?

  • economic development will affect how a place can respond to a hazard,
  • low= less likely to have effective mitigation strategies.
• What is magnitude and how does it affect human responses?

  • the size of the hazard,
  • high magnitude + high intensity= worse effects, so more management
• Intensity is the power of a hazard.
• What is distribution and does it affect human responses?

  • where hazards occur geographically,
  • high distribution= a lot of management strategies, population has adapted.
• What is incidence and how does it affect human responses?

  • the frequency of a hazard,
  • low incidence hazards- harder to predict, less management, more intense.
• What are the human responses to hazards?

  • Fatalism- passive response, belief that hazards are uncontrollable,
  • prediction
  • adaptation
  • mitigation
  • management
  • risk sharing.
• How does mobility affect hazard perception?

  • limited access to escape= perceive hazard to be greater threats than they are,
  • those who cannot easily leave an area quickly may feel more at risk.
• How does religion and beliefs affect hazard perception?

  • some may view hazard as put there by God for a reason,
  • may not perceive them as negative.
• How does education affect hazard perception?

  • more educated= may understand full effects,
  • less educated= may not evacuate.
• How does experience affect hazard perception?

  • more experience= know full effects of the hazards,
  • more experience= optimistic and unrealistic outlook on future hazards.
• How does wealth affect hazard perception?

  • wealthier- smaller hazard as they are less vulnerable,
  • wealthier also may view a risk as greater- more property damage and financial loss.
• What are the three major types of geophysical hazards?

  • geophysical- caused by land processes,
  • atmospheric- caused by atmospheric processes,
  • hydrological- caused by water movement.
• A hazard is a potential threat to human life and poverty.
• A natural disaster is a hazard which only occurs when there is a vulnerable population.
• How does preparedness affect seismic hazards?

  • prone areas have extensive awareness strategies and education in place,
  • warning systems,
  • evacuation plans and training.
• How does mitigation affect seismic hazards?

  • search and rescue,
  • emergency aid,
  • evacuation,
  • demolishing older, unsafe buildings,
  • tsunami wave breaks/ sea walls.
• How does adaptation affect seismic hazards?

  • move away from areas at risk,
  • capitalise on opportunities,
  • insurance,
  • changing lifestyle choices,
  • building 'earthquake proof' buildings.