The Hunga Tonga-Hunga Ha’apai volcano erupted on January 15th, leaving thousands without homes and internet access. The volcano, located in the South Pacific Kingdom of Tonga, has erupted no less than three times since late December but the January 15th explosion has proved to be the most devastating. Three people have been confirmed dead and every single home on one of Tonga’s outer islands has been destroyed. Several people have been reported injured, including one person on Ha’apai, eight on Nomuka Island, four on Fonoi Island, and two on Tunga Island. 84% of those living on any given island of Tonga have been affected by ashfall and tsunamis, as well.
The eruption created sonic booms, atmospheric shock waves, and tsunami waves that traveled as far away as Alaska. Tsunami advisories reached Australia, New Zealand, and the west coasts of North and South America. Parts of Japan saw nine feet tall waves and the west coast of the United States saw three and four feet high swells. In Peru, the waves caused an oil spill, and flooding caused the death of two people.
Hunga Tonga-Hunga Ha’apai was formed between December 2014 and January 2015 as the result of an underwater volcano eruption. Its summit reached 400 feet and it was the first of its kind to form in 53 years. Because it was a submarine volcano, it was studied less by scientists than land volcanoes. Volcanologists noticed activity in its area two days before the eruption, but its underwater location made it difficult for them to predict the size of a possible eruption. This is because most of the data used to predict eruptions come from instruments around the volcano, so gathering it is difficult for submarine volcanoes. Scientists still don’t know what caused the eruption, but they suspect it to have been an instantaneous reaction rather than something that had been bubbling under the surface for a long time.
“the main thing needed to create the tsunami is a huge displacement of water”
Scientists are also unsure about how the eruption caused tsunamis. Volcanic-induced tsunamis aren’t well-recorded, so there simply isn’t enough data to make a conclusion. Dr. Samuel Mitchell, a volcanologist, told Science Focus that “the main thing needed to create the tsunami is a huge displacement of water.” He said that in the case of the Hunga Tonga-Hunga Ha’apai, the displacement could have been caused by the underwater eruption, which would propel water away from the volcano, or large amounts of land moving in the ocean (two islands neighboring the volcano lost significant amounts of land due to the eruption).
“a New Zealand relief flight arrived with much-needed telecommunications equipment to re-establish limited internet connection.”
The Tonga government released a statement in which it said that communication between the various islands that make up Tonga was “an acute challenge” due to the effects of the eruption. However, the statement added that “a New Zealand relief flight arrived with much-needed telecommunications equipment to re-establish limited internet connection.”
The National Emergency Operations Centre said their main concern was water. Water supplies have been provided by New Zealand and are expected to arrive from Australia soon. The World Bank, the Asian Development Bank, Japan, and China have also pledged to provide support.
“His Majesty’s government is deeply appreciative to the international community for their generous and timely assistance in response to this unprecedented event,” the Tongan government said in response.