At https://www.livescience.com/planet-earth/volcanos/record-shattering-tonga-volcanic-eruption-wasnt-triggered-by-what-we-thought-new-study-suggests … the Hunga Tonga volcano was a real explosion – triggered by gas building up to a critical point. Scientists had thought it involved hot magma coming up against sea water. However, the volcano was extremely violent and was probably caused by gasses – but it also included an intense lightning storm. Was there also an electromagnetic input? There was also the tsunami wave that washed over the island.
The eruption fed itself by exploding away ever deeper layers of rock and releasing ever higher pressures of gas. It entered a runaway supercritical state – and the eruption only subsided once the gas reservoir had emptied.
Over at https://www.livescience.com/planet-earth/volcanos/antarctica-is-covered-in-volcanoes-could-they-erupt …. we are told the West Antarctic ice sheet covers 138 volcanoes. This is the peninsular that sticks out and was clearly joined to the extremity of South America at some point in geological history. Perhaps that is how the volcanoes originated. It is, in effect, the longest volcanic region on Earth. No wonder the alarmists are always telling us Antarctica is melting. In this, they mean the West Antarctic peninsular rather than the rather larger body, mainland Antarctica. The largest volcano, Erebus, has been continuously erupting since at least 1972. In addition, it is speckled with fumaroles – volcanic vents that release gases and vapour into the air. On top of that we have warm water from the tropical Pacific, forced to squeeze past Antarctica, in order to reach the Atlantic.