Tonga, the experts: “An eruption like this happens every 900 years”

LONDON – In the South Pacific such an eruption occurs every 900 years. The last was in 1100, at the time of our Middle Ages; the previous one in 200 AD, when the emperor Septimius Severus reigned in Rome and the world population was around 250 million people. “So another such event was to be expected,” says Professor Shane Cronin, a lecturer at the University of Auckland, New Zealand, one of the experts who have most closely studied theSoutherners Hunga-Ha’apai, the underwater volcano that exploded last Saturday about sixty kilometers from the archipelago of Tonga and which has since continued to erupt intermittently lava and embers.