Look at the ways that volcanic eruptions can be predicted

Why predicting the eruption of volcanoes are important:

• Volcanoes are able to destroy large areas of land during eruption
• Volcanoes can kill and injure many people during eruption

Ways to watch on volcanoes:

• Volcanoes can be continuously watched on by accurate measurements
• But the methods used to monitor the volcanoes are expensive
• They require skillful operators with complicated instruments in observatories
• Not all countries can afford to watch on their volcanoes

Most important methods & instruments used to predict eruption:

-Seismographic monitoring

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• Magma rising from a volcano causes moderate Earth tremors
• As magma gets closer to the surface of the Earth, the tremors would occur more frequently and get stronger
• These volcanic tremors are probably the most reliable sign to tell us that a volcano is going to erupt soon
• These tremors can be detected by automatic telemeter recorders, where the results are immediately sent to an observatory for analysis

-Tiltmeters

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• Tiltmeters are made up of 3 graduated pots put together into a triangle
• They are either filled up with water or mercury and are very accurate
• Ground deformation is frequently caused by magma rising within a volcano
• Tiltmeters measures ground deformation
• When the rising magma causes a bulge, tilting is measured
• As the volcano is about to erupt, this process takes place slowly

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- Surveillance by satellites

• This process is expensive and is still in its developing stages
• However, it may be the best way to predict volcanic eruptions in the future
• The Global Positioning System (GPS), is used to measure displacement on the ground, including those near to volcanoes, which might predict eruptions
• Orbiting satellites help the GPS to collect data

The above 3 methods are commonly used together

Signs of a volcanic eruption:

-Gas and steam may emit from a volcano before an eruption

• An increased amount of gas emissions and steam from furmaroles, mudpots, and solfataras usually show that the magma is rising nearer to the surface of the Earth
• Furmaroles are vents giving off gases or steam and are found on both active and dormant volcanoes
• Solfatara is an Italian word used to describe a furmarole that gives off sulfurous gases
• These information are not easy to collect as the gas emissions may damage the instruments and also harm the people collecting these information

After a volcano is studied:

-Hazard assessment maps may be created

• These maps show the areas of most danger and highest risk around a volcano
• It is important for the dangerous and risky areas to be correct and highlighted in detail
• This is to allow the people living in those places to evacuate before the volcano erupts