Led by researchers from the University of Bath and published today in Nature, the study combines extensive satellite data with ground-level observations to show that the eruption was unique in observed science in both its magnitude and speed, and in the range of the fast-moving gravity and atmospheric waves it created.

Following a series of smaller events beginning in December 2021, Hunga Tonga erupted on 15 January this year, producing a vertical plume that extended more than 50km (30 miles) above the surface of the earth. Heat released from water and hot ash in the plume remained the biggest source of gravity waves on earth for the next 12 hours. The eruption also produced ripple-like gravity waves that satellite observations show extended across the Pacific basin.

The eruption also triggered waves in our atmosphere that reverberated around the planet at least six times and reached close to their theoretical maximum speeds — the fastest ever seen within our atmosphere, at 320m per second or 720 miles per hour.

The fact that a single event dominated such a large region is described by the paper’s authors as unique in the observational record, and one that will help scientists improve future atmospheric weather and climate models.

…