Science & Technology

Volcanic lightning mystery has been solved

By T.K. Randall
June 15, 2016 ·  7 comments

Volcanic lightning is nothing if not impressive. Image Credit: CC BY 2.0 Oliver Spalt Photographs of this breathtaking natural phenomenon have been around for years, but until relatively recently the mechanism responsible for producing volcanic lightning had remained something of a mystery.

Now though, following an extensive study of eruptions at Japan's Mount Sakurajima, researchers from Ludwig-Maximillian University in Munich have finally succeeded in finding the answer using a combination of high-speed video footage and acoustic measurements.

The key, it turns out, lies in the way static electricity builds up from the friction created by ash particles as they are ejected from the crater. This electrification of the rising ash and dust is ultimately what produces lightning strikes to occur within the vicinity of the volcano.

A separate study by a second team of scientists also discovered that when ash clouds rise high enough, a build-up of ice particles can produce even more spectacular lightning strikes.It may even be possible to predict how large an ash cloud will become by analyzing its lightning.

"Regardless of the size of the eruption, any ash emissions are associated with electrical discharges," said volcanologist Dr Corrado Cimarelli.

"This we could measure and use to estimate the amount and distribution of the ejected ash - and from a safe distance of several kilometers and even in poor visibility."

"So we could estimate the ash distribution in the atmosphere early on and warn the aviation authorities."

Source: Gizmodo | Comments (7)

Tags: Volcano, Lightning