An undersea volcano erupted dramatically on Saturday near the peaceful nation of Tonga, sending tsunami waves crashing onto the shore and people rushing for higher ground. Tsunami advisories have been issued for other Pacific islands, the Australian east coast, Hawaii, Alaska and the US Pacific coast.
There were no immediate reports of injuries or extent of damage as all internet connection to Tonga was lost around 6.40pm local time.
The Fiji-based news site Islands Business reported that a convoy of police and military evacuated King Tupou VI from his palace near the shore. He was one of many residents heading for the higher ground.
In Tonga, home to around 105,000 people, video posted to social media showed large waves crashing into coastal areas, swirling around houses, a church and other buildings. Satellite images showed a huge eruption, with a plume of ash, steam and gas rising like a mushroom above the blue waters of the Pacific.
Authorities in the neighboring island nations of Fiji and Samoa have also issued warnings, telling people to avoid the shore due to strong currents and dangerous waves. In New Zealand, officials warned of possible storm surges from the eruption.
New Zealand’s private forecaster, Weather Watch, tweeted that people as far away as Southland, the country’s southernmost region, reported hearing sonic booms from the eruption. Others reported that many boats were damaged by a tsunami that hit a marina in Whangarei in the Northland region.
Earlier, the Matangi Tonga news site reported that scientists observed massive explosions, thunder and lightning near the volcano after it erupted early Friday. Satellite images showed a 5 km wide plume rising into the air about 20 km away.
The Hunga Tonga Hunga Ha’apai volcano lies about 64 km north of the capital, Nuku’alofa. In late 2014 and early 2015, a series of eruptions in the area created a new small island and disrupted international air travel to the Pacific archipelago for several days.
The Tonga Meteorological Service said a tsunami warning had been declared for the entire archipelago, and data from the Pacific Tsunami Center said waves of 80cm (2.7ft) had been detected.
A Twitter user identified as Dr Faka’iloatonga Taumoefolau posted a video showing waves crashing on the shore.
“Can literally hear the eruption of the volcano, the sounds are quite violent,” he wrote, adding in a later post, “It’s raining ash and tiny pebbles, darkness covers the sky.”
The explosion of the Hunga Tonga Hunga Ha’apai volcano was the latest in a series of dramatic eruptions.
Terrestrial imaging firm Planet Labs PBC had observed the island in recent days after a new volcanic vent began erupting in late December.
Satellite images captured by the company show how the volcano has shaped the region, creating a growing island off the coast of Tonga.
“The area of the island appears to have increased by almost 45% due to ashfall,” Planet Labs said days before the latest activity.
After Saturday’s eruption, residents of Hawaii, Alaska and along the U.S. Pacific Coast were urged to move away from the coast to higher ground and heed specific instructions from their local emergency management officials, said Dave Snider, tsunami warning coordinator for the National Tsunami Warning Center in Palmer, Alaska.
“We don’t issue reviews for this stretch of coastline like we did – I don’t know when the last time was – but it’s definitely not an everyday experience,” Snider said.
He said the crashing waves in Hawaii were just below the criteria for a more severe tsunami warning.
“It looks like everything will stay below the alert level, but that’s hard to predict because it’s a volcanic eruption, and we’re set up to measure earthquakes or seismic sea waves,” he said. Snider said.
The Australian Bureau of Meteorology has issued an evacuation order for Lord Howe Island and warnings for a large swath of the mainland’s east coast. Sydney’s Bondi Beach was evacuated overnight and a maritime threat warning remained in place on Sunday morning Australian time.
The Bureau of Meteorology said a tsunami wave height of 1.27m was observed over Norfolk Island at 9 p.m. AEDT and a wave of 82cm was recorded over the Gold Coast at 10:54 p.m. AED Saturday.
He said 1.10m high waves were recorded at Neds Beach on Lord Howe Island around 11pm AEDT and a 50cm surge was observed at Hobart’s Derwent Park around 11.44pm AEDT.
Smaller waves were recorded in Hawaii, Alaska and California.
Beaches and piers have been closed in Southern California as a precaution. The National Weather Service tweeted that there were “no major flooding concerns”. However, strong rip currents were possible and officials warned people to stay out of the water.