Tonga volcanic eruption is largest on record since 1883, scientists say

Scientists say the eruption of Tonga’s Hunga Tonga-Hunga Ha’apai volcano was the largest explosion documented by researchers since 1883.

The Hunga Tonga-Hunga Ha’apai eruption, which is responsible for only six deaths, was comparable in size to the Krakatoa explosion in Indonesia in 1883, according to the findings. published in Science†

The Tonga explosion generated pressure waves called Lamb waves, which traveled horizontally along the Earth’s surface for more than six days, according to the paper.

Those Lamb waves are usually associated with large, atmospheric explosions, such as other volcanic eruptions and nuclear tests.

The volcanic eruption in Tonga produced similar Lamb waves to the Krakatoa eruption that killed more than 30,000 people.

Scientists said nuclear explosions that also created Lamb waves — such as the largest nuclear test in the USSR in 1961 — had a similar amplitude but lasted a shorter period of time compared to large volcanic explosions like the one in Tonga.

That’s because volcanic explosions are much more complicated and not as pointed as nuclear explosions.

The January eruption also produced audible sounds that could be heard up to 10,000 miles away in Alaska, and generated infrasound — sound that cannot be heard by humans — that reverberated around the world.

Professor Corentin Caudron – who co-authored the paper – told the ABC that researchers had used more than 3,000 sensors and instruments around the world, often used to detect earthquakes and tsunamis, to arrive at their findings.

“Essentially what we did was compare what we’ve gathered, in terms of information, about all these waves that spread across the globe, [and] compare that eruption with others that have occurred in the past,” said Professor Caudron.