A team of scientists has said the volcano that erupted under the sea near Tonga in January set a record. The Tonga-Hunga Ha'apai volcano erupted on January the 15th. It was the biggest explosion ever recorded using modern instruments and technology. It was also the biggest to happen in the past 150 years. The scientists said the blast may have been as large as the Krakatoa eruption that took place in Indonesia in 1883. Dr Robin Matoza from the University of California said: "Tonga was a truly global event, just as Krakatoa was. But we've now got all these geo-physical [recording] systems, and they recorded something that was really [unmatched] in the modern data."

The volcanic eruption sent atmospheric shock waves and tsunami waves around the world. It also caused sonic booms that people heard 10,000km away in Alaska. The eruption even lifted clouds in the sky above the UK, which is 16,500km from Tonga. Scientists in the UK reported the sudden disappearance of clouds as they moved higher into the atmosphere. UK scientist Professor Giles Harrison said the atmosphere was "a remarkably interconnected thing". He said: "What happens on one side of the planet can [spread] around to the other side at the speed of sound." NASA has said the volcano's effects also reached space and could have affected the weather in space.