Because volcanoes are highly erratic, it becomes very difficult to predict volcanic eruptions. But there are ways of saving lives. Early tremors and earthquakes are often signs of a volcanic eruption—gases are emitted and the volcano expands by a few centimetres to a metre. The volcanologists carefully observe these signs. In 1991, before the eruption of the Pinatubo in Philippines, these signs were interpreted correctly and over 10,000 people were moved to safer places.
However, people often do not believe the scientists’ prediction. In 1985, before the eruption of Nevado Del Ruiz in Columbia, though the danger was predicted very early, the authorities did not react quickly and, as a result, 25,000 people died.
