Jul 31, 2009
When Mount Redoubt volcano in Alaska showed signs of erupting several months ago, researchers from New Mexico went there with the latest technology to measure the phenomenon.
The Lightning Mapping Array allows users to ’see through’ the dust and ash, and observe the lightning generated within the eruption. The results were some stunning images and valuable data in the study of volcanoes.
(Photo: Bretwood Higman)
“First, we see an eruptive or explosive phase,” physics professor Paul Krehbiel said. “Electrical activity is continuous and strong. We see a lot of small electrical discharges as hot gasses come out of the volcano.”
The second phase involves the ash cloud as it drifts away from the volcano with the wind. This phase is punctuated by discrete lightning – or lightning bolts.
“After the explosion is over, there is a subsequent phase of plume lightning,” Krehbiel said. “Full-fledged lightning occurs in the cloud of ash and water both above and downwind of the volcano.”