Electrical discharges can form awesome shows during eruptions. Some of the
most spectacular examples have been at
The effects can be spectacular when there is abundant fine
particles within a strongly expanding eruption cloud. It is thought that
friction between particles and gases cause potential differences that
create the lightning displays. Lightning bolts travel in any direction, and
occur in different shapes -- broad bolts, St. Elmo's fire (ball lightning),
as separate small sparks, branching displays such as at Sakurajima and others.
Lightning can strike the ground and be a hazard to life, but it most commonly
is only a hazard to communications and to human anxieties, for
the lightning occurs between clouds and from the eruption column to the
Blong, R.J., 1984. Volcanic Hazards. Academic Press Australia. 424 pp. (see
text on pages 62-64 with more references).
Gilbert, J.S., and Lane, S. J., 1994, Electrical phenomena in volcanic plumes, in Casadevall, T.J.,
ed., Volcanic ash and aviation safety: Proceedings of the first International Symposium on Volcanic
Ash and Aviation Safety: U.S. Geological Survey Professional paper 2047, p. 31-38.
Copyright (C) 1997, by Richard V.
Fisher. All rights reserved.