A level edexcel natural geography EQ2 Flashcards
What does a natural hazard mean?
A natural event that has the potential to harm people and property
what does a natural disaster mean?
The realization (great impacts) of the hazard- harm that has occurred, damage that has been done.
What does risk mean?
This is the potential or probability of a natural hazard causing harm and damage
What does resilience mean?
The ability of a community or individuals to cope with the impacts of hazards.
What is the PAR (pressure and release) Model?
The pressure and release model (PAR) is a framework for the vulnerability of places to natural hazards. It calculates the risk overall and vulnerability to the impacts of a disaster or natural hazard.
what are the root causes that are part of the PAR model?
Root causes are underlying issues a place faces such as limited access to food, power, etc. As well as political and economic problems.
what are the dynamic pressures that are part of the PAR model?
Dynamic pressures include rapid change and low capacity to keep up with that change, such as Urbanisation, investment, etc.
what are the unsafe conditions that are part of the PAR model?
Unsafe conditions include factors such as poor local economies, the physical environment, etc.
what is an example of root causes in Haiti?
root causes of Haiti include:
- per capita GDP US $1200
- 50% if the population is under 20 years old
what is an example of the dynamic pressures in Haiti?
dynamic pressures include:
- lack of education, training, and investment
- Rapid population change and urbanization
what is an example of unsafe conditions in Haiti?
unsafe conditions include:
- 25% of people live in extreme poverty
- 80% of Port-au-Prince’s housing is unplanned, informal slums
how do we measure Earthquakes? (what do we use to measure them?)
MMS- MOMENT MAGNITUDE SCALE
Earthquake magnitude is measured by the moment magnitude scale, an updated version of the richter scale.
It measures the energy released during an earthquake.
This is related to the amount of slip (movement) on the fault lane and the area of movement on the fault lane.
Mercalli scale
The Mercalli scale measures earthquake intensity on a scale of i-XII.
This older scale measures what people actually feel during an earthquake, i.e. the intensity of the shaking affects not the energy released.
It cannot be used to easily compare earthquakes as shaking experienced depends on building type and quality, ground conditions, and other factors.
How do we measure volcanoes?
We measure Volcanoes through the use of The VEI (volcanic explosivity index)-
This measures the magnitude of a volcanic eruption. It ranges from 0-8 and is a composite index combining eruption height, the volume of material (ash, gas, tephra) erupted, and the duration of the eruption.
VEI eruptions from 0-3 are associated with shield volcanoes and basaltic eruptions at constructive plate boundaries and mid-plate hotspots.
VEI eruptions from 4-7 occur at destructive plate margins, erupting high viscosity, high gas, high silica andesitic magma.
what are hazard profiles?
Hazard profiles- these are very useful ways in which to map out the characteristics of hazard events- such as speed, extent, and frequency.
The key to these is that it is shown through the relationships and correlations between different events
Hazards with the following characteristics present the highest risk:
- High magnitude, low-frequency events- these are the least ‘expected’ as, by definition, they are unlikely to have occurred in living memory.
- rapid onset events with low spatial predictability- could occur in numerous places and without warning.
- regional areal extent- affecting large numbers of people in a wide range of locations.
what are the problems with Hazard profiles?
- unpredictability of hazards makes these models less effective at accurately representing human responses to hazards.
- Time frame is not represented well.
- quite vague in treating every hazard the same
