Tectonic Hazards & vulnerability

Pyroclastic flow

  • dense cloud of ash and toxic gas that flows down the steepest side of a volcano. at temperatures of over 400 degrees at speeds of over 100 km/h.

Toxic gasses

  • carbon dioxide and sulphur can be produced by eruptions and can spread over a large area which can cause respiratory irritation and damage the environment.

Lahar

  • snow and ice on top of volcanos can melt during an eruption and mixes with ash to create a concrete like mudflow down the slopes of a volcano burring everything in its path. also known as a (Glacial Flood)

Tephra

  • violent eruptions can throw enormous clouds of ash high up into the atmosphere and this can then fall and settle on the ground, contaminating crops and water sources and if it stays in the atmosphere can cause global dimming

Lava flow

  • lava flows usually flow at relatively slow speeds but high temperatures of the lava will burn through anything in its path

Tsunamis

  • Tsunamis are caused by submarine eruptions or movement of oceanic plates which displace water producing large, fast moving waves that make land a flood low lying areas, destroying infrastructure and killing people

Volcano types

  • Shield volcanos are flatter and less volatile with less violent and smaller magnitude eruptions (the Hawaiian islands), normally forms from the sea floor
  • Composite volcanos are taller and cone shaped and form over land with higher magnitude and more violent eruptions

Shockwaves

  • shock waves can come after an earthquake and can cause further damage to buildings and people, the strongest are found at the epicenter of the quake

After shocks

  • shocks that occur as a secondary effect of an earthquake
  • comes in the form of P, S, R & L waves

Types of vulnerability

  • knowledge vulnerability
  • physical vulnerability
  • social vulnerability
  • economic vulnerability

Why some people choose to remain at risk

  • environmental refugees
  • economic vulnerability, people may lose jobs if they move away
  • religious groups may choose not to move as they may believe its an "act of god"
  • physical vulnerability, some people may not be able to move for various reasons or buildings dont provide much or any protection at all
  • knowledge vulnerability means that some people may not be educated on dangers or are just not aware of dangers around them

vulnerability mitigation and adaptation strategies

  • PAR Model: pressure and release model that combines four different factors to determine what should be tackled first in order to reduce risk before a disaster.
  • Parks Model: graph that illustrates the severity of disruption caused by a disaster and how long it takes for recovery or if the country affected even recovers as they may not totally recover at all
  • Risk Disc: Covers both disaster mitigation (prevention) and management to set out preparation and response and recovery