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Updated: Jul 13, 2026
07:51
Method for Recording Broadband High Resolution Emission Spectra of Laboratory Lightning Arcs
Published on: August 27, 2019
Electrical activity during the 2006 Mount St. Augustine volcanic eruptions.
R J Thomas1, P R Krehbiel, W Rison
1Langmuir Laboratory, New Mexico Tech, Socorro, NM 87801, USA. thomas@nmt.edu
Science (New York, N.Y.)
|February 27, 2007
Summary
Volcanic eruptions can generate lightning through two distinct electrical phases: an explosive ejection of charged material and subsequent in-plume discharges. These findings shed light on volcanic electrical phenomena.
Area of Science:
- Geophysics
- Atmospheric science
- Volcanology
Background:
- Volcanic eruptions are complex phenomena with poorly understood electrical aspects.
- Lightning generation within volcanic plumes has been observed but not fully characterized.
Purpose of the Study:
- To investigate the electrical activity associated with volcanic eruptions.
- To differentiate the modes and characteristics of lightning during an eruption.
Main Methods:
- Utilized radio frequency time-of-arrival (RF TOA) measurements.
- Employed interferometer measurements to analyze electrical discharges.
- Observed electrical activity during a Mount St. Augustine eruption.
Main Results:
- Identified two distinct phases of electrical activity during the eruption.
- Phase 1: Explosive ejection of positively charged volcanic ejecta with disorganized discharges and simple lightning.
- Phase 2: Conventional lightning within the volcanic plume, with delayed onset and downwind propagation, suggesting in situ charging.
Conclusions:
- Volcanic eruptions exhibit complex electrical behavior with at least two distinct modes.
- The electrical activity shares similarities with thunderstorm electrification processes.
- Further research is needed to fully understand in situ charging mechanisms in volcanic plumes.
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