La Palma volcano update: Volcanic lightning becoming more frequent
Over the past days, these have become more frequent. This goes along with the observed increase in explosive behaviour at the vents - more material is being fragmented into ash (as opposed to liquid lava fountains) and the resulting particles are probably finer as well.
Such volcanic "thunderstorms" are often seen during explosive eruptions producing large quantities of ash, although the details are still poorly understood. In a simplified model, the lightnings are the result of electric charges accumulating in different parts of the eruption cloud, where friction between the ash grains rip of electric charges (electrons) from each other. The more quantity of ash emitted, the faster and more turbulent it is moving and the finer the ash grains, the more likely this process occurs.
Video of the explosive activity yesterday:
Intensa actividad estromboliana a las 19.30 (hora canaria). Se observa la caída de bombas volcánicas en la cercanía del cono / Intense strombolian activity at 7.30 pm (Canarian time). The fall of volcanic bombs is observed in the vicinity of the cone pic.twitter.com/OjWy7zAIZy— INVOLCAN (@involcan) October 30, 2021