Can scientists really anticipate volcanic eruptions?
Yes, in many cases, but most reliably only for volcanoes that have been studied geologically. By studying deposits of rock and ash formed by past events, volcanologists can reconstruct the history of a volcano in considerable detail. This allows them to make general forecasts about future activity, because the past is often, though not always, a good guide to the future. For example, USGS scientists who studied Mount St. Helens during the 1970’s recognized that, for thousands of years, it had been the most active and explosive volcano in the entire Cascade Range. On that basis, they forecast that Mount St. Helens might be the next Cascade volcano to erupt, possibly before the year 2000. In 1980, their detective work paid off when the volcano erupted for the first time in 123 years.
