Sprites, elves and blue jets explained
Los Alamos National Laboratory researchers presented research last week
that shows how electrical discharges between thunderstorm cloud tops and
the upper atmosphere can be explained in the context of a runaway electron
beam that breaks apart air molecules.
Their model not only successfully recreates the optical characteristics
of the three discharges -- dubbed sprites, blue jets and elves -- but also
yields theoretically calculated radio and gamma ray emissions that match
The model also shows how elves, ephemeral flashes that appear miles
above the cloud tops of thunderstorms, can be kick-started by the electromagnetic
pulse from a sprite or jet at a lower elevation.
"Our work shows, for the first time, that there are strong theoretical
indications that elves can be caused not only by regular lightning discharges
but also by sprites and jets," said Yuri Taranenko, one of four Los Alamos
researchers involved in the study.
"This work has the potential to change prevailing views on how electromagnetic
pulses accompanying lightning are produced and what consequences they have.
It makes the picture of interactions in the upper atmosphere much more
rich and complex than we had previously thought," said Taranenko.
The work was presented in a series of papers at the American Geophysical
Union meeting which took place last week in San Francisco.
For more information, contact John R.
Gustafson, Los Alamos National Laboratory, (505)665-9197.
Copyright 1996, Environmental News Network, All Rights Reserved
ENN Daily News -- December 24, 1996