Volcanoes tend to be unpredictable. It would be nice to know when and why an eruption may occur. A forensic approach that links changes deep below a volcano to signals at the surface is described by scientists from the University of Bristol in a paper published today in Science. The research could ultimately help to predict future volcanic eruptions with greater accuracy. Using forensic-style chemical analysis, Dr Kate Saunders and colleagues directly linked seismic observations of the deadly 1980 Mount St. Helens eruption to crystal growth within the magma chamber, the large underground pool of liquid rock beneath the volcano.