p9 Flashcards
difference between prediction and forecasting?
Prediction is stating when an earthquake is going to take place.
Forecasting is giving a timeframe of when an earthquake could happen e.g. years to decades.
Hazard Prediction and Forecasting for earthquakes
- This is based on a statistical likelihood of an event happening at a particular location.
- These forecasts are based on data and evidence gathered through global seismic monitoring networks, as well as historical records.
- Warning signs (precursors) are used which can identify a characteristic pattern of seismic activity (foreshocks) or some other physical, chemical or biological change (such as animal behaviours or changes in radon emissions).
- For predictions to be useful – that is, to enable evacuation of affected areas – they must be highly accurate, both spatially and temporally.
- This at present is impossible and many geoscientists do not believe that there is a realistic prospect of this happening in the foreseeable future.
Hazard Prediction and Forecasting
Volcanoes:
These hazards can be predicted with some accuracy.
By placing equipment on a volcano as well as using remote equipment (such as GPS and satellite-based radar), scientists can monitor a volcano for signs that it might erupt, such as:
small earthquakes – rising magma breaks rock, causing small quakes
changes of the shape of the surface – as it pushes upwards, the magma builds pressure causing the surface to swell
changes to the ‘tilt’ of the volcano – magma movement inside the volcano can change the slope angle or tilt.
Despite this accuracy, predictions aren’t 100% correct and not all volcanoes around the world are monitored.
Despite it’s inaccuracies, why is forecasting important?
It can encourage governments to enforce better building regulations in areas of high stress, or create improved evacuation procedures in areas of highest risk.
The Hazard Management Cycle
Hazard management is a process in which governments and other organisations work together to protect people from the natural hazards that threaten their communities.
It can be put into a theoretical model as a continuous 4 stage cycle.
Different activities occur in each stage.
Mitigation, Preparedness, Response, and Recovery.
Preparedness
Being ready for an event to occur (public awareness, education, training)
Minimising loss of life and property
- Developing preparation plans
- Developing warning systems
- Stockpiling medicines, food, water etc.
- Education, training, drill
Response
Immediate action
taken after event (evacuation, medical assistance, rescue)
Coping with a disaster, the main aims would be to rescue people and reduce economic losses:
- Search and rescue efforts
- Evacuating people
- Restoring vital infrastructure like water and electricity
- Restoring vital services like law enforcement and health care
Recovery
Short-term:
- Providing aid, food, water, shelter
- Providing financial assistance so people can rebuild their livelihoods
Long term:
- Rebuilding homes
- Building and repairing infrastructure
- Reopening schools and businesses
Mitigation
Identifies the characteristics of the potential hazard and what can be done reduce their impact on people, such as:
- Land use zoning
- Building codes and regulation
- Protective defences (tsunami wall)
Disadvantages of the hazard management cycle
It may not be possible for smaller or less wealthy communities/countries to implement the hazard management cycle
Some hazards are less predictable, which means hazard management cannot account for every eventuality
Implementation of strategies may face opposition from local communities
Communication of the strategies may not reach all communities
Advantages of the hazard management cycle
It can be used by organisations and individuals
The cycle enables them to both prepare for and respond to hazardous events
It identifies potential hazards
Reduces the risks and saves lives
Improves the level of preparation
Park’s Model
The Park hazard-response curve is a model that shows how a country or region might respond after a hazard event.
It can be used to directly compare how areas at different levels of development might recover from a hazard event.
4 categories (pre-disaster, relief, rehabilitation and reconstruction)
Key things to remember about parks model
The impacts of a hazard event change over time – depending on factors such as the size of the hazard, the development level of the areas affected and the amount of aid received.
All hazard events have different impacts, so their curves are different.
Recovery depends on wealth, so wealthier (developed) countries will recover much faster
In hazard events that affect a number of countries (e.g. the Indian Ocean tsunami in 2004), each country has its own curve.
parks model diagram
The curve will vary for each event and area depending on the level of:
Preparation and planning
Development
Aid both national and International
Developing countries tend to be impacted more and recover more slowly
This can be clearly seen on the disaster response curve
