Danger And Effect of Volcanoes

What happens when a volcanoe erupts?

1) Lava Flows
Lava flows are a treat, but they are usually slow enough that people can get out of the way. Economic loss from lava flows--including burned buildings and ruined crops---is more common.

2) Falling Ash
In a explosive eruption, pent-up gases escape violently. Magma  breaks into pieces and burst from the volcano in a column of ash and fiery fragments. In a large eruption, tephra which is cooled fragments that fall back to Earth can cover vast areas with a thick layer of ash, presenting a mush greater hazard.

3) Pyroclastic Flows            
Pyroclastic flows are mixtures of very hot gas and tephra that cascade down a volcano's sides at high speeds. Because  pyroclastic flows can spread destruction over large areas and move at very high speeds,  they are extremely hazardous. Most people are not aware that this danger exists.

4) Mud and Debris Flow
Debris flows, fragments of mud and other drbris that flow down the sides of  a volcano, are another serious and little known hazard. debris flows often form when part of the volcano collapses, breaking up and flowing downhill. The large debris flow can travel great distances often everything in its path.

5)Other Dangers
Severe eruptions can disrupt the climate for long periods or cause atmospheric shock waves. Eruption can also cause tsunamis, volcanic earthquakes, or the release of suffocating gases.these hazards pose serious threats to both life and property. 

6)Monitoring Methods
A number of tools can be used to record these warning signs. Seismographs can detect small earthquakes while tiltmeters and geodimeter can measure the subtle swelling of a volcanoe. Correlation specrometers (COSPECS) can measure amount of sulfur dioxide--a gas that is released before the eruption.

7)The Problem of Prediction
Volcanologists are becoming very skilled at predicting the likelishood of an eruption. Still, anumber of barrier remain. It's very difficult to pinpoint exactly when aneruption will happen. Often,  moving magma doesn't result in an eruption , but intead cools below the surface. Monitoring potential eruptions don't occur without warning, however, if we set up monitoring devices, we should not be caught off guard by disastros eruptions.