How do volcanos kill people?

Lava flows are almost always too slow to run over people, but they can certainly run over houses, roads, and any other structures. Pyroclastic flows are mixtures of hot gas and ash, and they travel very quickly down the slopes of volcanoes. They are so hot and choking that if you are caught in one it will kill you. read more

Ash cloudsfrom volcanoes may also produce lighting, which can kill people andstart fires. Molten rock on the surface, called lava, is extremelyhot and can easily start fires. Unlike pyroclastic flows, however,lava flows are usually slow-moving. read more

Active volcanoes are dangerous places. They can wipe out whole cities and kill large numbers of people. The ghost-like casts from the Roman city of Pompeii are a reminder of the lethal eruption of Mount Vesuvius in AD79, which killed thousands and preserved their bodies in the position of their death. read more

They form as rainfall, snow, or melting ice and wash ash deposits off the slopes of volcanoes and into surrounding valleys at high speeds. In 1985 about 25,000 people were killed by lahars at Nevado del Ruiz, Colombia. In large eruptions volcanic ash can travel hundreds or even thousands of kilometres. read more

One of the most subtle ways a volcano can kill is also the most devastating. Under certain conditions, volcanic activity at the bottom of a deep lake can infuse the lake with a huge amount of CO2. Cold lakes often have stratified temperature layers. Tremors or other factors can cause the lake to "turn over." This releases the CO2 very suddenly. read more