Electrical Activity Of Explosive Volcanic Eruptions At Low Latitudes

BAISSAC, DAIANA M.; NICORA, M. GABRIELA; ÁVILA, ELDO E.; BADI, GABRIELA A.

Tel Aviv

Congreso; 17th International Conference on Atmospheric Electricity (ICAE); 2022

We live in a dynamic Earth and as such, there are natural phenomena that manifest this dynamism. A clear example that occurs frequently is volcanic eruptions. The impact that volcanic eruptions have on society is important both in the long and short term, causing damage to society and may even produce meteorological changes at local or regional scales in the case of very intense eruptions.Explosive volcanic eruptions are frequently accompanied by electrical discharges. The electrical discharges generated in the volcanic plume during the eruption evolve with the eruption, having different characteristics over time. According to Thomas (2010), three types of electrical discharges can be distinguished, starting with the vent discharges generated at the beginning of the eruption and of short length and energy; then, near-vent lightning are generated at low altitude once the eruptive column develops and do not exceed tens of meters; and finally, the plume lightning are generated in the convective zone once the volcanic plume has developed and these are usually most energetic, reaching important lengths.These plume lightning are very similar to those associated with meteorological thunderstorms and for this reason it is possible to register them remotely using existing meteorological lightning location systems.Currently, in addition to the ground-based lightning location networks such as WWLLN (World Wide Lightning Location Network) and ENTLN (Earth Network Total Lightning Network), which have been used for some time now, there are also meteorological satellites that remotely monitor different regions of the world, especially geostationary satellites, with varied sensors provide an invaluable source of atmospheric information. These tools, together or individually, have proven to be useful in detecting an explosive eruption and the presence of volcanic ash in the atmosphere by remote sensing. A number of related papers have demonstrated the connection between changes in the dynamics of the eruption and the generation of electrical discharges. But they have also shown the difficulty of distinguishing whether the nature of the detected electrical discharge is volcanic (due to the generation of a volcanic plume) or meteorological (due to a thunderstorm at the site). This implies a problem for remote monitoring of eruptions using lightning location systems, mainly in tropical regions where thunderstorm days can reach 100 thunderstorm days per year.In our work, we use the plume lightning detected by terrestrial and satellite lightning location systems, during volcanic eruptions occurred from 2018 onwards in a set of volcanoes located in the tropical zone, together with satellite images and bulletins and reports that inform the evolution for each eruption. With this information, we characterize the electrical activity in each eruption, its temporal evolution and the relationship between electrical activity and other parameters of the volcanic eruption, in order to obtain similarities and differences in the analyzed cases and to be able to improve the future use of discharge location systems for monitoring volcanic eruptions and the presence of volcanic ash in the atmosphere.