Prediction
Geography: Edexcel A Level, topic 1.4.2
Tectonic Hazard Prediction
Theoretical frameworks can be used to understand the prediction, impact and management of tectonic hazards. These involve various forms of modelling.
Key terms
- Prediction is knowing when, and where, a natural hazard will strike so that meaningful action can be taken (e.g. evacuation).
- Forecasting gives a ‘percentage chance’ of a hazard occurring.
- E.g. There is a 25% chance of a magnitude 7.0 earthquake happening in the next 20 years.
Volcanoes
- Most volcanoes give some form of advance warning.
- Monitoring equipment on volcanoes can measure changes as magma chambers fill and an eruption nears. Examples include:
- Tiltmeters, which record volcanoes ‘bulging’ as magma rises.
- Seismometers, which record minor earthquakes that indicate magma movement.
- Gas spectrometers, which analyse gas emissions that can point to increased eruption likelihood.
Earthquakes and tsunamis
- Earthquakes give little advance warning - they are hard to predict.
- Seismic gaps are areas that have not experienced an earthquake for some time and are ‘overdue’. These areas are regarded as being particularly high risk.
- For tsunamis, seismometers can tell an earthquake has occurred and can locate it. Ocean monitoring equipment can then detect tsunamis in the open sea and information can be relayed to coastal areas so that they can be evacuated.
Test yourself on Prediction
Which of the following words means 'giving a percentage chance of a hazard happening'?
What would you use to record volcanoes 'bulging' as magma rises?