The expected after-effects of the volcanic eruption off Tonga

Tsunami waves caused by a massive underwater volcano eruption have flooded Tonga.

The volcano’s sonic boom was heard in Fiji, 1000 kilometres from the eruption site, while the tsunami caused boat damage in New Zealand and inundated low streets in Santa Cruz, California.

The damage in Tonga is not yet known, with a 20 kilometre high ash cloud preventing surveillance flights from assessing the damage, and the force of the eruption cutting internet to the nation.

Volcanologist at the Australian National University, Richard Arculus, says the eruption is probably the largest since Mount Pinatubo in the Philippines erupted in 1991.

He says this eruption is likely to have similar after effects to that one, more than three decades ago.

“That was a major eruption,” he told Neil Mitchell.

“The sulfuric acid droplets stayed in the stratosphere for a couple of years and reduced the Earth’s temperature by a fraction of a degree.”

Professor Arculus says the eruption “could keep going, certainly for weeks to a few months”.

It’s not yet clear if this is the climax of the eruption, or whether there will be more explosion events in the weeks, months or years ahead.

Press PLAY below to hear how the eruption caused a tsunami