Record-shattering Tonga volcanic eruption sent atmospheric waves zipping around the Earth

" TORONTO (CTV Network) — Scientists have found evidence that an underwater volcanic eruption in the South Pacific earlier this year, the biggest in decades, created pressure waves so strong they circled the planet multiple times and blasted through the Earth’s atmosphere.

A team led by a researcher out of the University of California, Santa Barbara published a study this month in the journal Science that examined the atmospheric waves generated by the eruption of the Hunga volcano in mid-January 2022, which created a tsunami that devastated the island nation of Tonga.

The scientists say it had been nearly 140 years since an eruption of that scale shook the Earth, going back to the 1883 Krakatau eruption in Indonesia.

The researchers say they were most interested in the behaviour of an atmospheric wave known as a Lamb wave, which was the dominant pressure wave produced by the Hunga eruption.

After the eruption, the researchers say the waves travelled along Earth’s surface and circled the planet in one direction four times and in the opposite direction three times, similar to the Krakatau eruption.

The waves also reached the ionosphere, or where Earth’s atmosphere meets space, rising more than 1,126 kilometres per hour to an altitude of approximately 450 kilometres.

The researchers say the Hunga volcanic eruption provided unprecedented insight into the behaviour of multiple atmospheric wave types.

“Lamb waves are rare. We have very few high-quality observations of them,” study co-author David Fee from the University of Alaska Fairbanks Geophysical Institute said in a news release.

“By understanding the Lamb wave, we can better understand the source and eruption.”...

PO2 Russell "Russ" Lincoln Volcanic Eruptions are always an Awe Inspiring Event. Ideally Viewed from a Distance. Not Close Like I did 15 Jun 1991 Mt Pinatubo.