Fastest gravity waves recorded on Earth

The massive eruption of the submarine Hunga Tonga-Hunga Ha-apai volcano in the South Pacific on 15 January 2022 generated gravity waves that lasted for 12 hours and circled the planet six times. The waves reached peak speeds up to 269±3 m/s (968 km/h; 602 mph), close to the speed of sound, in the stratosphere. The findings were published in the journal Nature on 30 June 2022.

It also produced the fastest atmospheric shockwaves ever recorded on Earth, travelling at a record rate of up to 319±4 m/s (1,148 km/h; 714 mph).

This eruption, which has been likened in scale to the infamous Krakatoa event of 1883, was record-setting for other reasons too: it triggered off-the-scale readings of volcanic lightning, peaking at more than 5,200 discharges per minute in the early morning of 15 January and released an unprecedented 146 teragrams of water vapour up to 53 km (33 mi) high into the stratosphere; the plume contained the equivalent of 58,000 Olympic swimming pools' worth of water, which could take several years to dissipate.

The research into the atmospheric waves was a multinational collaboration between the University of Bath, Oxford University (both UK), University of Massachusetts Lowell, Virginia Tech, University of Colorado Boulder (all USA), Curtis University (Australia) and Sorbonne Université (France), led by Dr Corwin Wright of the University of Bath.