An Undersea Volcano Explodes near Tonga

On 15 January 2022, the submarine volcano Hunga Tonga-Hunga Haʻapai produced one of the most violent explosive events ever documented by modern instruments. Situated approximately 65 kilometres north of Tongatapu, Tonga's main island, the underwater mountain had shown sporadic unrest since late December 2021 before briefly falling quiet. The climactic detonation launched a massive plume 58 kilometres into the mesosphere, blotting out daylight across nearby islands and releasing dense showers of ash, stone, and explosive shockwaves across the southwestern Pacific.

The atmospheric blast generated powerful pressure waves that resonated across the entire planet. Ground barographs and satellite sensors observed atmospheric Lamb waves circling the globe multiple times, while the audible roar travelled across thousands of kilometres, recorded as distant booming in New Zealand, Alaska, and Canada. Instruments also logged hundreds of thousands of lightning discharges within the volcanic cloud. Scientists determined that the explosion was the largest atmospheric disturbance measured by modern gauges, drawing historical comparisons to the celebrated 1883 detonation of Krakatoa.