Tectonic processes and hazards (EQ 2) Flashcards
Natural disaster definition
A natural hazard which has caused significant damage to a community or society, and they are no longer able to cope using their own resources
Risk
The probability or potential of a natural event to cause harm and damage
Resilience
The capacity of a community, individual or nation to cope with the impacts of a natural hazard.
What is the PAR model?
A theoretical framework for the vulnerability of places to natural disasters.
What are the 3 things that contribute to a disaster (PAR model)
Root causes - Limited access to power, structures and resources. Also poor political/economic systems
Dynamic pressures - Lack of investment, training and other factors such as rapid urbanisation and population change
Unsafe conditions - Physical environment, local economy, public actions
Give 2 root causes, dynamic pressures and unsafe conditions in Haiti 2010
Root causes - GDP per capita is 1200 USD, 50% of the population is under 20
Dynamic pressures - Lack of education and training, rapid urbanisation and population growth
Unsafe conditions - 80% of housing in Port Au Prince is informal slums, 25% of people live in extreme poverty
How do geological factors affect vulnerability and resilience?
Degree of urbanisation - More urbanisation, higher potential risk
Isolation and accessibility - Isolated areas have less potential life losses but are more at risk during recovery and rescue due to accessibility problems
Population density - Potential for death, injury and damage is greater.
How does governance affect vulnerability and resilience?
- Poor governance leads to a lack of investment and planning for natural hazards
- Haiti government had very little control over land ownership or housing regulations
How does development affect vulnerability and resiliance?
Education - educated population allows for more effective planning and management, less deaths and an increase in the capacity to cope
Housing - Resilient housing infrastructure may create more resilient people + decrease vulnerability
Healthcare - Better healthcare will increase chances of survival and treatment of those impacted
GDP - wealth provides all of the above
Moment Magnitude Scale (MMS)
Measures energy released by an earthquake
Logarithmic scale
Related to the amount of slip on the fault line
Mercalli Scale
Measures impacts seen and felt from the earthquakes
Measures the intensity of the shaking effects, not the energy released
Scale of I -XII
Volcanic explosivity index
Composite index combining eruption height, volume of material erupted and the duration
Scale of 0-8 but can go up to 9
What are the six factors on a hazard profile
Magnitude
Speed of onset
Duration
Areal extent
Spatial predictability
Frequency
Why do we have hazard profiles?
To map out and compare the characteristics of hazard events
What 3 types of hazard with the following characteristics present the highest risk?
- High magnitude, low frequency events
- Rapid onset events with low spatial predictability, occur in numerous places and without warning
- Regional areal extent, can affect large numbers of people in a wide range of locations
Problems of hazard profiles
- Unpredictability of hazards makes these models less effective at accurately representing human responses to hazards
- Time frame is not presented very well
- Quite vague in treating every hazard the same way
Human, Economic and Environmental impacts from Tohoku, Japan EQ and tsunami
- 16,000 deaths
- 6,000 injuries
- 130,000 displaced
- USD 235bn cost
- Industrial production prevention
- 40m wave tsunami
- Liquefaction
- Coastal subsidence of 0.6 meters
Human, Economic and Environmental impacts from Eruption of Eyjafjallajökull, Iceland
- 500 local families displaced
- Roads impassable
- Water supply contaminated
- £130m lost per day for airline companies
- £5m lost per day for tourism
- Major jokhulhaulp
- Ash dissolved in Atlantic ocean, causing plankton boom
Human, Economic and Environmental impacts from the earthquake in Sichuan, China
- 69,000 deaths
- 5 million made homeless
- 370,000 injured
- £140bn in losses
- £75m repair in communications infrastructure
- Fire and gas leaks were common
- Water pollution
Human, Economic and Environmental impacts from Eruption of Mt Pinatubo, Phillipenes
- 850 deaths
- 1.2m made homeless
- 58,000 evacuated
- Bridges and transport infrastructure destroyed
- 650,000 jobs lost
- Volcanic ash destroyed soil fertility
- Fast flowing lahars
- Global cooling
Human, Economic and Environmental impacts from the Asian 2004 tsunami and earthquake
- 280,000 deaths
- Outbreak of cholera
- Limited food supply
- £9.4bn damage
- Sri Lankan fishing industry destroyed
- Tourism collapsed
- Pollution and debris hazards
- Smaller islands completely destroyed
Human, Economic and Environmental impacts from the Haiti 2010 earthquake
- Over 220,000 deaths
- 300,000 injuries
- Further 30% in poverty
- £8.5bn in damage
- One third of commercial buildings collapsed
- Water pollution and cholera outbreak
- Rubble and debris remained on the landscape for months
Vulnerability factors for the Tohoku, Japan earthquake (inequality, governance, geographical factors)
- 0.910 HDI, very well developed nation with a good education system
- Well prepared, good planning and preparation
- Epicentre 70km off the coast, 1 minute Tokyo warning signal
Vulnerability factors for the Eyjafjallajökull, Iceland eruption (inequality, governance, geographical factors)
- Highly developed nation, sparsely populated, high incomes per capita
- Very well rehearsed planning and preparation. Stable political landscape
- Lies on mid-Atlantic ridge and a large magma plume, used to tectonic events so the population is well rehearsed on evacuation procedures etc. making them less vulnerable.
