Tectonics - EQ2 Flashcards
What are the factors are involved with governance?
- Meeting basic needs
- Planning
- Environmental management
- Preparedness
- Corruption
- Open-ness
Meeting basic needs
When food supply, water supply and health needs are met the population is physically more able to cope with disaster
Planning
Land-use planning can reduce risk by preventing habitation on high risk slopes, areas prone to liquefaction or areas within a volcanic hazard zone
Environmental management
Secondary hazards, such as landslides, can be made worse by deforestation. The right monitoring equipment can warn off some hazards, such as lahars
Prepardness
Education and community preparation programmes raise awareness and teach people how to prepare, evacuate and act
Corruption
Siphoning off money ear-marked for hazard management or ‘kick-backs’ and bribed to allow illegal or unsafe buildings, increase vulnerability
Kick-backs
Illicit payment made in exchange for facilitating a transaction
Open-ness
Governments that are open, with a free press and media, can be held to account, increasing the likelihood that preparation and planning take place
Why is it more beneficial if a hazard was to impact rural areas?
Urban areas have more assets than rural areas (hospitals, emergency services, food stores and transport connections) which increase resilience and coping capacity compared with isolated rural places. High population density mean more people are affected
How is risk increased (result of increased vulnerability)?
- Population growth
- Urbanisation and urban sprawl
- Environmental degradation
- Loss of community memory about hazards
- Very young or very old population
- Ageing, inadequate infrastructure
- Greater reliance on power, water and communication systems
How is risk reduced (mitigation)?
- Warning and emergency-response systems
- Economic wealth
- Government disaster-assistance programmes
- Insurance
- Community initiatives
- Scientific understanding
- Hazard engineering
Why are more people at risk than others?
- Lack access to basic needs (suffient food and water in normal times)
- Housing is informally constructed with no regard to hazard resilience
- Access to healthcare is poor and disease and illness are common
- Education levels are lower, so hazard perception and risk awareness is low
Mercalli scale
Measures earthquake intensity (what people actually feel during an earthquake - ground shaking)
What is the issue with the Mercalli scale?
It can’t be use to easily compare earthquakes as shaking experienced depends on building type and quality, ground condition etc.
Why is the relationship between magnitude and death toll weak?
- Some earthquakes cause serious secondary impacts (tsunami’s, landslides)
- Earthquakes hitting urban areas have greater impacts than rural areas
- Level of development and Prepardness affects death toll
- Isolated, hard to reach places could have a higher death toll becuase rescue and relief take longer
- High magnitude could not cause any deaths in an unoccupied area
On the VEI scale what types of volcanoes and eruptions are associated with 0-3?
Shield volcanoes and basaltic eruptions at constructive plate boundaries and hotspot volcanoes
On the VEI scale what volcanoes and eruptions are associated with 4-7?
At destructive plate margins, erupting high viscosity, high gas, high silica andesitic magma
On the VEI scale what volcano is associated with 8?
No modern human has ever experienced a VEI 8 super volcano
- Impacts would be felt globally
On hazard profiles which characteristics present the highest risk?
- High magnitude, low frequency - least ‘expected’ and are unlikely to have occurred in living memory
- Rapid onset with low spatial predictability - occur in numerous places and without warning
- Regional areal extent - affecting large numbers of people in a wide range of locations
What are the threshold values to determine whether a natural hazard has become a natural disaster?
- 10 or more deaths
- 100 or more people affected
- $100 million in economic losses
Why is the relationship between risks, hazards and people complex?
- Unpredictability of hazard’s timing and magnitude
- Lack of alternatives - people stay due to lack of options (skills, knowledge, work or lack of space)
- Dynamic hazards - threats change over time and can be affected by human influence
- Cost-benefit
- Russian roulette reaction - fatalism, acceptance of risks whatever you do
Factors that increase resilience/ capacity to cope
- Emergency evacuation
- Rescue and relief systems in place
- React by helping each other, to reduce numbers affected
- Hazard-resistant design or land-use planning have reduced the numbers at risk
What is the equation used in the PAR model?
Risk = hazard x vulnerability
