Enquiry Question 2: Why do some tectonic hazards develop into disasters? Flashcards
Natural Hazard
A natural process/event that has the potential to threaten life and property
Natural Disaster
T realisation of a hazard when it causes damage/injury (e.g. 10 or more people are killed, or 100 people or more are affected
Vulnerability
The ability to anticipate, cope and recover from a natural hazard/disaster.
Resilience
The ability to protect lives, livelihoods and infrastructure from damage and to repair damage.
Hazard risk equation
Risk (R) equals hazard (H) multiplied by vulnerability (V), divided by the capacity to cope (C)
Pressure and Release Model (PAR)
A model which examines the underlying causes of a disaster - 1) the factors affecting vulnerability, and 2) the natural processes/hazard itself.
Social impact
The effects of an event/process on people and their health, livelihoods and wellbeing.
Economic impact
The effects of an event/process on business, trade, industry, employment and infrastructure.
Environmental impact
The effects of an event/process on the landscape and ecology.
magnitude
The size of the tectonic event - either the size of the volcanic eruption (VEI) or the amount of energy released from the hypocentre during an earthquake (MMS)
intensity
The strength of shaking and resulting damage from an earthquake (e.g. Mercalli scale)
Moment Magnitude(Mw) Scale
Based on measurement of the maximum motion recorded by a seismograph, and also based of the concept of seismic moment (Source: USGS)
Mercalli scale
Measurement of the effects of an earthquake experienced by people. Lower values generally deal with the manner in which the earthquake is felt by people. Higher values are based on observed structural damage.
Volcanic Explosivity Index (VEI)
A relative scale that enables explosive volcanic eruptions to be compared with one another. It considers the volume of pyroclastic material ejected (e.g. tephra, ash), the height of the eruption column and the duration of the eruption.
Speed of Onset
How quickly the peak of the hazard event occurs
Areal extent
The size of the physical area affected by the event.
duration
The length of the event
frequency
The number of events in a given period of time.
spatial predictability
How easy it is to pin point/estimate when an event will happen
Hazard Profile
A diagram that illustrates the main characteristics of different types of tectonic hazards)
Governance
The way in which local and national governments plan for, and respond to, tectonic hazards. This can contribute to an areas vulnerability and resilience.
Inequality of access
The way in which not everyone has the same opportunities regarding education, healthcare, housing and income. This can affect people’s vulnerability and resilience.
Population density
The number of people per sq. km of land area
degree of urbanisation
The proportion of people living in urban areas. Also closely linked to higher population densities.
