EQ2: Why do some tectonics develop into disasters? Flashcards
What is a hazard?
A natural event with the potential to harm people and property
What is a disaster?
A hazard which has killed more than 10 people, 100 more were affected, a state of emergency was declared and they requested international assistance
Why do people choose to live in areas associated with tectonic activity?
-Job opportunities
-Volcanic activity causes fertile soil
-Climate/ecosystems
-Economic reasons e.g cheaper land
-Not fully educated on the hazards e.g dormant volcano
What is vulnerability?
The ability to anticipate, cope with, resist and recover from a natural hazard, it also takes into account the location of settlements
What is resilience?
The ability to protect lives, livelihoods and infrastructure from destruction and to restore areas after a natural hazard has occurred
What decreases resilience?
-Low doctor dependant ratio
-Large scale rural-urban migration
-Lack of skills
-Lack of revenue
What increases resilience?
-Good communications
-Pre planning
-Medical supplies and services available
-Positive attitudes of people
What is the pressure and release model?
Theory that a disaster occurs when two opposing forces interact (the vulnerability and the natural hazard)
What is physical vulnerability?
When people live in hazard prone areas that offer little protection
What is economic vulnerability?
When people risk losing their jobs, assets or money
What is social vulnerability?
When a household or community is unable to support the disadvantaged people within it
What is knowledge vulnerability?
Exists when people lack education or training and there are no warning or evacuation systems in place
What is environmental vulnerability?
Exists where the area that people are living in has increased in hazard risk because of the population pressure, forcing people into riskier areas
What factors can affect the economic impact of tectonic hazards?
-Level of development in the affected areas
-Insured/non insured losses
-Urbanisation
-Peoples resilience to recover
What human factors affect vulnerability?
-Level of income
-GDP
-Millionaire cities/mega cities
-Physicians per 1000 people
-Informal housing
How do you calculate risk?
(hazard x vulnerability) / capacity to cope
How do social and economic factors affect vulnerability?
-Communities with poor healthcare suffer more
-People’s level of wealth affects how well they cope
-Lack of education means people are unaware of how to cope
How do physical and environmental factors affect vulnerability?
-Rapid urbanisation = informal housing
-Accessibility of an urban area
-High population density
How do governance and political factors affect vulnerability?
-Education and practised hazard responses
-Enforcement of building codes and regulations
-Level of corruption
-Efficiency of emergency services
What is the moment magnitude scale?
A scale which is more accurate than the richter scale as it uses:
-The energy released from the seismic waves
-The area of the rupture and the resistance of the rock
-It has no upper limit
-It is not used to express damage
What are the advantages of the moment magnitude scale?
-More accurate than the richter scale as it uses more values
-No upper limit
-Accurate and not subjective as it is recorded on a seismometer
-Uses geological evidence
What are the disadvantages of the moment magnitude scale?
-Not used to express damage
-No indication of impacts
-Uses scientific equipment which may not be available in all parts of the world
-Many people don’t understand the logarithmic scale
What is the mercali scale?
A scale which measures an earthquake by measuring the intensity rather than the magnitude
-It uses a set of definitions based on the people around the earthquake opinions and observations
-Uses reports and photos of the event
-Focuses on impacts of the earthquake
-Rated on a scale 1-12 (instrumental to catastrophic)
What are the advantages of the mercali scale?
-Shows impacts, more specific for when help is needed
-Has a description as well as a number
-Cost effective so can be used more widely
What are the disadvantages of the mercali scale?
-Doesn’t work in rural or desert settings as there is no infrastructure
-Subjective as it works on opinions
-Has an upper limit
-Some of the descriptions aren’t very clear or detailed
-Not understood by the wider public
What is the VEI scale?
-The volcanic explosivity index
-Measures explosivity with eruption cloud height, volume of products erupted and qualitiative observations
-Measures on a scale 0-8
-As each number increases there is a tenfold increase
What is governance?
The government of a country running and organising the country
What does good governance look like?
-Democracy = right to vote
-The national and local government are keeping people safe, healthy and educated
-Low corruption
-High GNI
-Listening to the public’s needs and wants
What is corruption?
Where those in power use resources for their own personal gain, it involves abusing power and dishonesty
What is corruption measured on?
The corruption perception index
What is the swiss cheese model?
The cumulative effect model used for risk management and analysis
-Layers of cheese represent the safety systems
-Holes represent weakness in the systems
Theory that an accident occurs when all the holes line up
