As in many remote Pacific countries, the archipelago of Tonga is connected to the world by a single cable, about the width of a garden hose, that carries hair-thin optical fibers across a vast ocean floor.
That lonely canal is the means by which Siniva Filise, who lives in Wales and is part of the… large Tongan diaspora, starts each day with a video call from her mother 10,000 miles away. “She’s like the alarm clock—she doesn’t care what time it is,” Mrs. Filise said. “She just calls.”
But the phone has been silent for the past four days. Tonga’s undersea cable was severed by a massive volcanic eruption Saturday night and the country now faces weeks of digital darkness as a repair ship prepares to make its way out of Papua New Guinea.
The ship is not expected to reach Tonga until February 1, after a voyage of more than eight days. After that, it will perform the difficult task of extracting two sections of damaged cable from the ocean floor and splitting it into replacements, with the threat of further volcanic activity ever present.
Meanwhile, the only word about Tonga’s immediate needs after last week’s eruption and ensuing tsunami has come through the country’s few satellite phones. The Red Cross said on Wednesday that drinking water supplies had been severely affected by ash and salt water, and that two New Zealand navy ships carrying large amounts of water would arrive on Friday. Tonga’s main airport was left unusable as workers attempted to clear ash from a runway.
On Tuesday evening, the government in Tonga offered its first update on the situation there, saying the death toll had reached three and evacuations were underway from remote islands, where a number of homes were destroyed or damaged.
The submarine cable connecting Tonga to the global internet went live in 2013 and runs between the cable and neighboring Fiji, which is about 800 kilometers northwest.
More than 430 cables, like the one serving Tonga, lie at the bottom of the Earth’s oceans, spanning nearly a million miles in total. It is basically internet plumbing, and like all plumbing, it can have cracks.
A few minutes after Saturday night’s volcanic explosion, internet traffic to Tonga took a dip. Just over an hour later, the connection dropped completely, said Doug Madory, director of internet analytics at Kentik, a network monitoring company. “I think that was when something hit the cable,” Mr. Madory said.
The next day, the cable went into what is known as single-end feed mode, in which it was fed from Fiji but not Tonga, said Craige Sloots, a spokesperson for Southern Cross Cable Network, which is part of the collective work to to restore connection.
Analysts have identified a breach in both the international section of the Tonga cable, which lies about 37 miles offshore from the capital Nuku’alofa, and the islands’ internal network. The cause is believed to be a landslide or seafloor shift, said Mr. Ditch in an email.
Under all circumstances, repairing this internet plumbing is complicated work. Add to that the complications of an active volcano and the tentacle-like effects of the coronavirus pandemic, and it’s even more challenging, said Amanda Watson, a researcher in the Australian National University’s Pacific Affairs Department.
“One of the main problems is that there are very few ships equipped to lay and repair submarine cables,” she said.
Repairs can end up costing hundreds of thousands of dollars, with daily costs for the vessel repairing the cable, the CS Reliance, between $35,000 and $50,000. According to the New Zealand Ministry of Foreign Affairs, SubCom, the company responsible for the repair, estimates that it will take at least four weeks to restore the connection.
Work on each break, when it happens, will begin by dragging two grappling hooks — a type of anchor with several hooks — across the ocean floor, to find the severed ends of the cable, which may have been pushed several miles apart.
The two ends are then hoisted aboard the ship, a colossal vessel over 150 meters long. Finally, in a special cleanroom on board, the damaged parts are cut out and a replacement cable is welded in.
Up to 50 people could be on board to assist with the repair, said Dean Veverka, the director of the International Cable Protection Committee, a nonprofit in Britain. “It’s a lot of work to get the cable back on the ship,” he said.
As the repair ship prepared to leave Papua New Guinea, the Hunga-Tonga-Hunga-Ha’apai volcano — which exploded Saturday night in what was believed to be the world’s largest volcanic eruption in three decades — continued to rumble.
With no monitoring equipment nearby, volcanologists rely on ground observations or satellite imagery to try to predict the volcano’s next movements. The ash clouds obscuring the island home to the submarine volcano, about 40 miles from the Tongan capital, make those efforts even more difficult.
Tonga is located due west of one of the world’s deepest ocean trenches, where the Pacific Plate dips beneath both the Kermadec and Tonga Plates. The collision speed between the plates is extremely high, creating a chain of an estimated 30 volcanoes, of which Hunga-Tonga-Hunga-Ha’apai is one.
Possible results range from the volcano shutting down to successive explosive eruptions, which could trigger further tsunamis, said Shane Cronin, a professor of earth sciences at the University of Auckland in New Zealand.
“This is all very speculative, because we don’t have any seismometers around,” he said. “A lot of our knowledge about the volcanic activity is all reactionary — we have no forecasting capabilities, with no seismic stations working there and no other instruments at all. It’s very frustrating.”
In the meantime, the sudden spotlight on the oft-overlooked South Pacific draws attention to its remoteness and the challenges that come with it.
“It has been a useful process to raise awareness of the practical issues of communication infrastructure in the region,” said Dr. Watson of the Australian National University.
For those anxiously awaiting the familiar sound of a WhatsApp message, the distance is clearer than ever. “I’m sure I’m the same as every Tongan all over the world,” said Mrs. Filise. “Just wait and hope for news.”
Damien Cave reporting contributed.