Hunga Tonga-Hunga Ha'apai: Eruption triggers small tsunamis
14 Jan 2022
For a few days it had been quite quiet around the island volcano Hunga Tonga-Hunga Ha'apai, but yesterday it reported back with a huge eruption. The volcanic eruption is so strong that small tsunamis arrive on the main island of Tonga. The wave heights are a little less than 60 cm. That may not be much, but even small tsunamis can push a few 100 metres inland and cause damage along the coasts. But there are no reports of this at the moment. In any case, the region is on tsunami alert. The height of the ash column is impressive: according to VAAC Wellington, it rose to almost 18,000 metres. The last detected eruption cloud still reached a height of 15,000 m.
Due to the expected air pollution, authorities advised residents of the archipelago to stay indoors and wear breathing masks outdoors. The strongest pollution is likely to come from the emitted sulphur dioxide at a greater distance from the volcano. However, ordinary masks, which are likely to be available in many households in Corona times, will not help against this. To filter sulphur dioxide, you need proper gas masks with special filters. Corona masks, or gas masks with included filters, usually help against dust, i.e. volcanic ash.
DeepL
Hunga-Tonga Ha’apai Volcano, Tonga - Pacific Ocean
15 Jan 2021 • (133m / 436feet )
I took screen captures of the (ongoing) event, as well a gif animation - which illustrates chillingly how the ash cloud expands, at the same time sends sort of "pressure wave" ripples through the neighboring clouds in a circle over 1600 km in diameter.
At german Vulkane.net, Marc Szeglat wrote
Japan's Meteorological Agency has issued a tsunami warning for the southern Amami islands and Tokara island chain in Kagoshima Prefecture and a tsunami advisory for wide coastal areas facing the Pacific Ocean. The highest tsunami observed so far is 120 centimeters in the Kominato district of Amami-Oshima Island at 11:55 p.m. on Saturday. And a 3-meter tsunami may reach coastal areas where tsunami warnings are in effect.
The shockwave was recorded as a sudden uptick in air pressure as far away as Alaska, Belize and multiple locations in Florida. The global wave is expected to converge on southern Algeria, giving an especially strong signal there.
High-altitude balloon and satellite measurements indicate that the exhaust plume has reached the stratosphere, as high as 60,000 feet. Ash and sulfurous compounds spreading through the stratosphere could create unusual sunsets in the evenings ahead.
If that is sound wave from the explosion which is 30 kms far, that was one mighty explosion. Is there somewhere video of the shock wave? That would be also interesting to see.One of the eruption blasts hitting tonga, where people/teenagers are at the beach...