Tuesday 17 May 2022 10:37 AM Tonga eruption on a par with Krakatoa, study says trends now

Tuesday 17 May 2022 10:37 AM Tonga eruption on a par with Krakatoa, study says trends now
Tuesday 17 May 2022 10:37 AM Tonga eruption on a par with Krakatoa, study says trends now

Tuesday 17 May 2022 10:37 AM Tonga eruption on a par with Krakatoa, study says trends now

Tonga's volcanic eruption in January produced the strongest recorded waves from a volcano since the eruption of Krakatoa in 1883, scientists say. 

Hunga Tonga-Hunga Ha'apai, an underwater volcano in the South Pacific, created sound waves heard as far as Alaska 6,200 miles away when it erupted on January 15. 

Researchers say the eruption was 'on a par' with Krakatoa, and the biggest explosion ever recorded by modern geophysical equipment. 

It was significantly larger than every atmospheric nuclear bomb test, meteor explosion and volcanic eruption in history, including Mt. St. Helens in 1980 and Pinatubo in 1991. 

Just before nightfall reached Tonga, the eruption (lower left) sent atmospheric waves around the globe. Radar surveys before and after this month's eruption show only small parts remain of two Tongan islands above the volcano – Hunga Tonga and Hunga Ha'apai

Just before nightfall reached Tonga, the eruption (lower left) sent atmospheric waves around the globe. Radar surveys before and after this month's eruption show only small parts remain of two Tongan islands above the volcano – Hunga Tonga and Hunga Ha'apai

Hunga Tonga-Hunga Ha'apai, an underwater volcano in the South Pacific, spewed debris as high as 25 miles into the atmosphere when it erupted in January

Hunga Tonga-Hunga Ha'apai, an underwater volcano in the South Pacific, spewed debris as high as 25 miles into the atmosphere when it erupted in January 

NASA: TONGA ERUPTION EQUIVALENT TO HUNDREDS OF HIROSHIMAS 

Tonga's volcanic eruption unleashed explosive forces equivalent to up to 30 million tonnes of TNT – hundreds of times more than Hiroshima's atomic bomb, NASA said in January. 

Hunga Tonga-Hunga Ha'apai, an underwater volcano in the South Pacific, spewed debris as high as 25 miles into the atmosphere when it erupted on January 15.

It triggered a 7.4 magnitude earthquake, sending tsunami waves crashing into the island, leaving it covered in ash and cut off from outside help. 

It also released somewhere between 5 to 30 megatons (5 million to 30 million tonnes) of TNT equivalent, according to NASA Earth Observatory. 

As a comparison, the US atomic bomb dropped on the Japanese city of Hiroshima in August 1945 was estimated to be about 15 kilotons (15,000 tonnes) of TNT. 

Read more:  Tonga eruption equivalent to hundreds of Hiroshimas

Advertisement

Barometer readings show the volcano produced a pressure wave that travelled around the world four times over six days – approximately the same as for Krakatoa. 

Audible sound from the eruption was reported 6,200 miles (10,000km) away in Alaska, compared to 3,000 miles (4,800km) away 140 years ago when Krakatoa erupted. 

The research, led by the University of California, involved a team of 76 scientists from 17 nations who studied the eruption's atmospheric waves, based on data from ground-based and spaceborne instruments. 

The pressure wave was picked up by atmospheric recording equipment at the University of Reading, as well as hundreds of other monitoring points, as it travelled around the planet. 

'Reviewing data from recording equipment has revealed the sheer scale of this once-in-a-century eruption, which dwarfed every previously recorded explosion created by man or nature,' said study author Professor Giles Harrison, an atmospheric physicist at the University of Reading.

'Because of the vast and widespread effects seen from the oceans to the upper atmosphere, the eruption is bound to be studied for decades to improve predictive models.' 

According to the authors, the atmospheric waves produced were comparable with those from the biggest ever nuclear explosion, from the Tsar Bomba in 1961, but lasted four times longer. 

'This atmospheric waves event was unprecedented in the modern geophysical record,' said lead author Robin Matoza, an associate professor at UC Santa Barbara's Department of Earth Science. 

This graph shows the global distribution of recording geophysical sensors used in this new study

This graph shows the global distribution of recording geophysical sensors used in this new study

The island of Hunga Tonga-Hunga Haʻapai was destroyed by the volcanic eruption in January, leaving two small remnant islands. 

Prior to the explosion, the twin uninhabited islands Hunga Tonga and Hunga Ha'apai were merged by a volcanic cone to form one landmass.

Hunga Tonga and Hunga Ha'apai are themselves remnants of the northern and western rim of the volcano's caldera – the hollow that forms shortly after the emptying of a magma chamber.  

Researchers think an initial eruption sunk the volcano's main vent below sea

read more from dailymail.....

NEXT The UK's most sustainable restaurants are revealed - and it's bad news for KFC ... trends now