New Zealand's military on Monday morning was able to send a surveillance flight to Tonga to assess the extent of the damage from a huge undersea volcanic eruption.
A towering ash cloud had prevented the military from launching any flights earlier to the Pacific island nation.
Communications with the island nation remained limited after the internet was cut soon after the eruption on Saturday evening.
There were no reports of injuries or deaths, although concerns remained for the fate of people on some of the smaller islands near the volcano.
Meanwhile, scientists said they didn't think the eruption would have a significant impact on the Earth's climate.
Huge volcanic eruptions can sometimes cause global cooling as sulfur dioxide is pumped into the stratosphere. But in the case of the Tonga eruption, initial satellite measurements indicated the amount of sulfur dioxide released would only have a tiny effect of perhaps 0.01 C global average cooling, said Alan Robock, a professor at Rutgers University in New Jersey.
Satellite images showed the spectacular undersea eruption Saturday evening, with a plume of ash, steam and gas rising like a giant mushroom above the South Pacific waters.
A sonic boom could be heard as far away as Alaska and sent pressure shockwaves around the planet twice, altering atmospheric pressure that may have briefly helped clear out the fog in Seattle, according to the National Weather Service. Large waves were detected as far as the Caribbean due to pressure changes generated by the eruption.
In Tonga, it sent tsunami waves crashing across the shore and people rushing to higher ground.
With internet and phone lines down, friends and family members around the world were left anxiously trying to get in touch.
New Zealand Prime Minister Jacinda Ardern said there had not yet been any official reports of injuries or deaths in Tonga, but cautioned that authorities hadn't yet made contact with some coastal areas and smaller islands.
"Communication with Tonga remains very limited. And I know that is causing a huge amount of anxiety for the Tongan community here," Ardern said.
She said there had been significant damage to boats and shops along the Tongan coastline. The capital, Nuku'alofa, was covered in a thick film of volcanic dust, Ardern said, contaminating water supplies and making fresh water a vital need.
'Humbling and scary' spectacle
Aid agencies said thick ash and smoke had prompted authorities to ask people to wear masks and drink bottled water.
In a video posted on Facebook, Nightingale Filihia was sheltering at her family's home from a rain of volcanic ash and tiny pieces of rock that turned the sky pitch black.
Undersea volcano erupts in Pacific, forcing islanders of Tonga to rush to escape tsunami
3 days agoDuration 1:50An undersea volcano erupted near the Pacific nation of Tonga, sending tsunami waves crashing across the shore and people rushing to higher ground. 1:50
"It's really bad. They told us to stay indoors and cover our doors and windows because it's dangerous," she said. "I felt sorry for the people. Everyone just froze when the explosion happened. We rushed home." Outside the house, people were seen carrying umbrellas for protection.
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One complicating factor to any international aid efxjmtzywfort is that Tonga has so far managed to avoid any outbreaks of COVID-19. Ardern said New Zealand's military staff were all fully vaccinated and willing to follow any protocols established by Tonga.
Dave Snider, the tsunami warning co-ordinator for the National Tsunami Warning Center in Palmer, Alaska, said it was very unusual for a volcanic eruption to affect an entire ocean basin, and the spectacle was both "humbling and scary."
The tsunami waves caused damage to boats as far away as New Zealand and Santa Cruz, Calif., but did not appear to cause any widespread damage. Snider said he anticipated the tsunami situation in the United States and elsewhere to continue improving.
Tsunami advisories were earlier issued for Canada, in four zones in coastal British Columbia — and in Japan, Chile, Hawaii, Alaska and the U.S. Pacific Coast. The U.S. Geological Survey estimated that the eruption caused the equivalent of a magnitude 5.8 earthquake. Scientists said tsunamis generated by volcanoes rather than earthquakes are relatively rare.
Communication channels still down
Rachel Afeaki-Taumoepeau, who chairs the New Zealand Tonga Business Council, said she hoped the relatively low level of the tsunami waves would have allowed most people to get to safety, although she worried about those living on islands closest to the volcano. She said she hadn't yet been able to contact her friends and family in Tonga.
"We are praying that the damage is just to infrastructure and people were able to get to higher land," she said.
U.S. Secretary of State Antony Blinken wrote on Twitter he is "deeply concerned for the people of Tonga as they recover from the aftermath of a volcanic eruption and tsunami. The United States stands prepared to provide support to our Pacific neighbours."
Tonga gets its internet via an undersea cable from Suva, Fiji. All internet connectivity with Tonga was lost at about 6:40 p.m. local time on Saturday, said Doug Madory, director of internet analysis for the network intelligence firm Kentik.
On Tonga, which is home to about 105,000 people, video posted to social media showed large waves washing ashore in coastal areas and swirling around homes, a church and other buildings. A Twitter user identified as Dr. Faka'iloatonga Taumoefolau posted video showing waves crashing ashore.
Stay safe everyone 🇹🇴 <a href=https://www.cbc.ca/news/world/”https://t.co/OhrrxJmXAW”>pic.twitter.com/OhrrxJmXAW
—@sakakimoana
"Can literally hear the volcano eruption, sounds pretty violent," he wrote, adding in a later post: "Raining ash and tiny pebbles, darkness blanketing the sky."
The explosion of the Hunga Tonga Hunga Ha'apai volcano, about 64 kilometres north of Nuku'alofa, was the latest in a series of dramatic eruptions. In late 2014 and early 2015, eruptions created a small new island and disrupted international air travel to the Pacific archipelago for several days.
Earth imaging company Planet Labs PBC had watched the island in recent days after a new volcanic vent began erupting in late December. Satellite images showed how drastically the volcano had shaped the area, creating a growing island off Tonga.
"The surface area of the island appears to have expanded by nearly 45 per cent due to ashfall," Planet Labs said days before the latest activity.
Following Saturday's eruption, residents in Hawaii, Alaska and along the U.S. Pacific Coast were advised to move away from the coastline to higher ground.
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It's too early to tell how much ash was produced by the eruption because the volcanic cloud included vapour resulting from sea water interacting with the hot magma, experts said.
"That interaction … adds extra energy to the explosion and creates taller and bigger ash clouds," said Michelle Coombs, a scientist at the U.S. Geological Survey's Alaska Volcano Observatory.
The ash cloud was drifting westward and aircraft will be likely diverted around its periphery as a precaution, said Scott Bachmeier, a research meteorologist at the University of Wisconsin-Madison.
