NPR Story
10:41 am
Fri July 19, 2013

Volcano 'Screams' Before Eruption

In 2009, Alaska's Redoubt volcano erupted and sent plumes of ash miles into the air. But underground, there was even more activity. In a study published in Nature Geoscience, researchers say the volcano experienced a large number of pre-eruption earthquakes that created a "scream."