The Tonga volcanic eruption was biggest in a century. (AFP File Photo)
The Hunga TongaHunga Ha'apai volcano shook the world when it erupted in January this year. It generated tsunamis across the Pacific and in other oceans and even lifted the clouds over the UK, more than 16,000 kilometres way. But surprisingly, the underwater volcano remains intact.
This has been revealed by New Zealand's National Institute for Water and Atmospheric (NIWA) Research after a month-long study. NIWA has posted the results of their research on Twitter, which it said has "defied scientists' expectations".
The research was conducted by a ship which reached close to the volcano to map the post-eruption shape of Hunga-Tonga Hunga-Ha'apai and the surrounding seafloor.
NIWA scientists said their vessel RV Tangaroa recorded up to seven cubic kilometres of displaced material - the equivalent of 3 million Olympic-sized swimming pools. But, despite the ash, the volcano continues to stand tall.
"Scientists found ash still in the water column, suggesting the volcano may still be venting, with correlated decreases in oxygen, meaning potential impacts for food production & carbon sequestration," NIWA said in one of its tweets.
Expedition leader Kevin Mackay said he was taken aback by the results of the research.
"Given the violence of the eruption on 15 January, I'd expected the edifice to either have collapsed or been blown apart, and this is not the case," he told the BBC.
Mr Mackay said that the seafloor showed some dramatic effects of the eruption, like is fine sandy mud and deep ash ripples as far as 50km away from the volcano, with gouged valleys and huge piles of sediment.
The volcanic eruption, most powerful in a century, was heard as far away as Alaska and shredded an 80-kilometre stretch of Tonga's undersea telecommunications cable. The tiny island's telecommunications system was severely restricted and took experts nearly a month to restore it.