How are volcanic eruptions measured?
Eruptions are commonly measured in terms of tonnage of “ejecta” produced. Unlike an earthquake, where there is a definite correlation between damage and the earthquake magnitude scale, volcano measurement does not reflect damage. Can volcanic eruptions be predicted? Until relatively recently, when an orbiting satellite was used in a test to monitor hot spots on the planet’s surface, scientists did not have a reliably accurate method to predict volcanoes. The new monitoring system processes data from two geo-stationary environmental satellites, enabling scientists to monitor volcano-prone areas up to four times per hour. The system accurately predicted the November 1998 eruption of the Popocatpetl volcano on the outskirts of Mexico City and an eruption on the Galapagos Islands chain in September 1998.
