In explosive eruptions, particles of ash, ice and rock collide inside the plume and become electrically charged, just as in a storm cloud. The result: lightning bolts streaking through the ash column. In January 2022, the undersea eruption of Hunga Tonga–Hunga Ha'apai unleashed the most intense lightning storm ever measured, peaking at over 2,000 flashes per minute.
On 27 August 1883, the eruption of the Indonesian volcano Krakatoa was heard as far away as Rodrigues Island, nearly 4,800 km away. Its pressure wave was picked up by barometers worldwide and circled the globe several times. The tsunamis that followed killed more than 36,000 people.
The deepest known point in the ocean, Challenger Deep, lies roughly 10,900 m below the Pacific surface. Drop Everest in and its summit would still sit about 2 km underwater. Down there, the pressure is more than 1,000 times what you feel at sea level, roughly a tonne pressing on every square centimetre.