Lightning and Electrical Activity during the 2006 Eruption of Mt. Augustine
Lightning during several of the volcanic eruptions was observed using the same technique that we use to observe thunderstorms. In mid January 2006 we set up two stations about 100 km east of the volcano, near Homer, AK. We received and located the source of thousands of radio emissions from the vicinity of Mt Augustine during the January 28 eruption. With two stations we were able to determine the azimuthal direction to the sources, their power, the time history and relationship to other pulses. On one lightning flash we used an interferometric effect to infer altitude. We observed two distinct forms of electrical activity. The first was many short bursts (each less than a millisecond) that occurred coincident with the explosive eruption. These seemed to be short discharges (up to several hundred meters) that occur just as the material leaves the volcano. The other type was very similar to the lightning that we see in thunderstorms. Most of these lightning flashes began several minutes after the explosive eruption. Following the largest eruption on January 28 we observed about 300 discharges in a period lasting 11 minutes. Initially these flashes lasted only a few milliseconds, but the final ones lasted more than one half second, had many branches 10s of km in length. Most or all of this lightning was in the plume. Because of the bad weather there were no visual observations.
R.J. Thomas P.R. Krehbiel W. Rison H. Edens S.R. McNutt G. Tytgat
Langmuir Laboratory, New Mexico Tech, Socorro, NM 87801, USA Alaska Volcano Observatory, University of Alaska, Fairbanks, AK 99775, USA
国际会议
第13届国际大气电学会议(The 13th International Conference on Atmospheric Electricity)
北京
英文
2007-08-13（万方平台首次上网日期，不代表论文的发表时间）