Science Alert June 22, 2023
Using a combination of satellite- and ground-based sensors a team of researchers in the US (USGS (Vancouver), industry, Los Alamos National Laboratory, NASA (Huntsville, AL), NASA, VA) investigated the rate of volcanic lightning (>2,600 flashes min−1) and what it revealed about the dynamics of the submarine eruption. In map view, lightning locations form radially expanding rings. They showed that the initial lightning ring was co-located with an internal gravity wave traveling >80 m s−1 in the stratospheric umbrella cloud. Buoyant oscillations of the plume’s overshooting top generated the gravity waves, which enhanced turbulent particle interactions and triggered high-current electrical discharges at unusually high altitudes. The researchers attributed the intense lightning activity to an exceptional mass eruption rate (>5 × 109 kg s−1), rapidly expanding umbrella cloud, and entrainment of abundant seawater vaporized from magma-water interaction at the submarine vent… read more. Video TECHNICAL ARTICLE
… Four phases of eruptive activity can be distinguished using umbrella cloud growth, maximum plume heights, and lightning rates…. Credit: Geophysical Research Letters, Volume 50, Issue 12 e2022GL102341, 20 June 2023