Reports arrive on a tsunami in Indonesia caused by Krakatoa that has left scores dead. I’d recently watched this video of the 1883 eruption which postulated an interesting theory. Most super-volcanoes, such as that which created the Aso caldera, achieve such explosive velocity due to water drawn down by subduction, heated to supercritical temperatures, then flashing into steam when a smaller eruption relieves pressure on the magma chamber. The theory for Krakatoa was that the upper magma chamber was connected to a much deeper one, resulting in a flood of magma from the mantle that blew the island away. The video is worth a look; not just Aso but many other nearby volcanoes are active or dormant. https://www.youtube.com/watch?v=MrEIT66oPqU&t=4479s
Our thoughts go out to the victims in Indonesia. - William
