Spectacular Lightning Revealed in 2009 Mount Redoubt Eruption

The explosive eruption of Alaska's Mount Redoubt volcano in March and April 2009 provided a superb opportunity for studying volcanic lightning. The energetic explosions produced powerful volcanic lightning storms, the largest of which rivaled the intensity of the massive supercell thunderstorms that frequent the midwestern Great Plains. Although lightning often has been observed in the plumes of explosive volcanic eruptions, only a handful of detailed studies have delved into the origins of volcanic lightning. Active volcanoes tend to be situated in remote locations, where they are difficult to observe, and often have sudden, unpredicted eruptions. Even when the eruptions are observed close at hand, the volcanic clouds are intensely opaque, obscuring most of the lightning from view.