Tsunami in Tonga: the damage caused by the violent eruption of the volcano

Unverified video showing water rushing into a church.

Photo: @JOHNNYTEISI / copyright

The massive volcanic eruption in Tonga, which triggered tsunami waves on Saturday, filled these South Pacific islands with ash, as well as cutting off electricity and damaging communications.

Jacinda Ardern, New Zealand’s prime minister, said the tsunami caused “significant damage,” sweeping boats ashore and hitting shops along the shore.

Information from Tonga is scarce, but so far no deaths have been reported.

Local residents say Tonga looks like “a moonscape” after being covered by a layer of volcanic ash.

Dust is contaminating water streams and right now fresh water has become a necessityaccording to Ardern.

Charities said the ash and smoke had prompted authorities to ask residents to drink bottled water and wear masks to protect their lungs.

Flooding in Tonga after tsunami waves.


One of the worst eruptions in decades

The undersea volcano erupted on Saturday, spewing a plume of ash into the sky and prompting warnings of 4-foot waves. The eruption was so strong that could be heard in New Zealand, 2,383 km from Tonga.

As the sky was covered with ash, several videos showed the traffic jams and how many people fled in cars from the lower areas. Hours later, phone and internet lines went down in Tonga, leaving the island’s 105,000 residents virtually without communication.

Ardern said power was being restored in parts of Tonga and mobile phones were slowly starting to work. However, the situation in some coastal areas remains unknown.

Unable to speak to their friends and family, many Tongans in Australia and New Zealand were concerned for their safety.

Flooding in Tonga after tsunami waves.

Consulate of the Kingdom of Tonga.
Images on social networks show the desolation caused by the floods.

New Zealand and Australia are sending surveillance flights to assess the extent of the damage.

Satellite images show that some smaller islands have been completely submerged under water.

Experts say that the eruption of the Hunga-Tonga-Hunga-Ha’apai volcano is one of the most violent in the region in decades.

The eruption triggered tsunami alerts in several countries, including Chile, the United States and Japan. Some flooding was reported in coastal areas in California and Alaska.

Satellite images show the destruction of the volcano

Analysis – Jonathan Amos, science correspondent

Hunga-Tonga-Hunga-Ha’apai was first seen by scientists after Saturday’s eruption when the European Union’s Sentinel-1A satellite flew overhead.

This spacecraft is a radar platform and can see through clouds and ash that obscure the surface below.

The images clearly showed that much of the crater rim above the ocean waters had been destroyed, a sign of the ferocity of the explosion.

Satellite image of the volcano.

Satellite images captured the magnitude of the eruption.

Need for more studies

Researchers will study to understand the cause of a tsunami that caused waves not only on nearby islands but along several beaches around the Pacific Ocean.

To what extent was the explosion itself responsible? Pressure waves can generate what is called “meteotsunami”.

Another possibility is that perhaps the displacement of the water was the result of an unseen collapse from part of the volcano below the ocean surface.

In the next few days the facts will be clarified when more information about what happened is obtained.

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