Alaska Volcano's Scream Could Explain Eruption Power

Redoubt volcano screamed in 2009

Several volcanoes erupted in 2009 – but only one screamed in the process. Its unique guttural howls provide an unrivalled glimpse into the heart of a volcanic eruption, and may hold clues to the driving forces that cause volcanoes to blow their tops.

The Redoubt volcano near Anchorage in Alaska sprang to life in March 2009, exploding more than 20 times during a two-week-long eruption that spewed ash some 15 kilometres upwards into the stratosphere.