Tonga Volcano

The Home Reef, which is about 25 kilometres southwest of Late Island in the Vava'u Group, has experienced five eruptions since Saturday.

The reef covers an area of about seven hectares.

Tonga Geological Services are advising mariners to stay at least four kilometres clear of the reef until further notice.

Prior to these latest eruptions, there were eight eruptions on October 10.

Home Reef has been intermittently active since October last year.

New analysis produced by scientists from around the world, including NIWA, indicates the flows travelled up to 122km/h — up to 50% faster than any other recorded.

The eruption of Hunga-Tonga Hunga-Ha'apai and the ensuing tsunami killed four people in Tonga after becoming the largest atmospheric explosion recorded by modern instruments.

Scientists say that material from the volcanic eruption collapsed into the ocean, triggering a huge surge of rock, ash, and gas that caused extensive damage to Tonga's underwater telecommunication cables some 80km away.

An international team of researchers demonstrated an air pressure wave triggered by volcanic eruptions could produce an "equatorial plasma bubble".

An equatorial plasma bubble, or EPB, is a hole formed in the equatorial areas of the ionosphere, which severely disrupts satellite-based communications.

It can delay radio waves as well as degrade the performance of GPS.

When Hunga-Tonga-Hunga Ha'apai went off, it sent a shockwave around the world, produced a plume of water and ash that soared higher into the atmosphere than any other on record, and triggered tsunami waves that ricocheted across the region - slamming into the archipelago which lies southeast of Fiji.

Coral reefs were turned to rubble and many fish perished or migrated away.

"Our world was upside down. It was like our heart was wrenched out of our body, hearing the news, thinking there would be no more Tonga," Valeti Finau, who lives in New Zealand, said.

To mark the first anniversary of the disaster, community leaders gathered at churches in Tonga and around the world.

In Auckland, New Zealand, an event was held by the Tongan Council of Churches, chaired by Reverend Tevita Finau and the Aotearoa Tonga Response Group led by MP Anahila Kanongata'a-Suisuiki.

Hu'akavameiliku was at home on January 15, 2022, when the Hunga-Tonga-Hunga-Ha'apai volcano exploded with a destructive power the world had not seen since the Krakatoa eruption of 1883. Hu'akavameiliku was meeting with a local church community group when he heard what he first thought was thunder. Within minutes he was notified of the volcano's eruption. Hu'akavameiliku recalls his first thoughts:

Scientists used satellite equipment to measure the plume created by the Hunga Tonga Hunga Ha’apai undersea volcano. The blast, or eruption, of the volcano happened in January in the South Pacific near the island nation of Tonga.

The 10-minute eruption caused a series of large ocean waves, known as a tsunami, to hit areas around the world. The huge plume the volcano created included smoke, gas and water vapor.

The January eruption of Hunga-Tonga Hunga-Ha’apai and the subsequent tidal wave caused devastation in Tonga and killed people as far away as South America. The atmospheric shockwave caused by the eruption was felt as far away as the UK.

Kaniva News reports the robot boat, the Maxlimer, is based in Tonga, but will return to the site of the volcano to complete the survey of the opening, known as a caldera.

The eruption "obliterated" a volcanic island north of the Tongan capital Nuku'alofa, the agency said.

Tonga says more than four-fifths of the population has been affected by the tsunami and falling ash.

Three people were confirmed killed in the tsunami last week.

Before the eruption, the Hunga Tonga-Hunga Ha'apai volcanic island was two separate islands joined by new land formed in 2015.

Nasa says the eruption was so powerful all the new land is gone, along with "large chunks" of the two older islands.

The eruption has covered the Pacific islands in ash, cut power and severed communications.

Up to 80,000 people there could be affected, the International Federation of Red Cross and Red Crescent Societies (IFRC) told the BBC.

New Zealand Prime Minister Jacinda Ardern said the tsunami had wreaked "significant damage".

No deaths have been reported so far.

Information remains scarce, however, and New Zealand and Australia are sending surveillance flights to assess the extent of the damage.