When the Hunga Tonga-Hunga Ha’apai (Hunga) volcano erupted 65 kilometres northwest of the Tongan capital of Nuku’alofa on 15 January, it was among the largest volcanic eruptions recorded.
It generated a blast so powerful it sent massive pressure waves rippling through the atmosphere and around the globe. Recent analyses of the eruption have shown just how incredibly powerful it was:
- The pressure waves were the fastest ever observed within our atmosphere, reaching speeds of 1,158 kilometres per hour (close to the theoretical limit)
- The waves lapped the planet at least six times.
- The plume of gas and particles was 58 km tall at its highest point, making it the largest volcanic plume in the satellite record (just for interest, that’s up into the mesosphere, the third layer of the atmosphere above Earth’s surface).
- Above the Karman line that marks the edge of space about 100 km above our planet, shockwaves triggered by the eruption stirred up winds with speeds of up to 720 kilometres per hour.
- The eruption generated almost 590,000 lightning strikes over the course of three days.
- Extreme winds emanating from the volcano affected electric currents in the ionosphere, forcing east-flowing streams to flip direction dramatically and surge to five times that of normal peak power.
- Hunga’s eruption sent ripples racing across the ocean, producing tiny, fast-traveling meteotsunamis (a series of waves driven by air-pressure disturbances) that appeared in the Pacific Ocean, Atlantic Ocean and Mediterranean Sea.
The statistics are simply astonishing. But it’s worth remembering that behind the numbers were three deaths and thousands of Tongans whose communication with the rest of the world was cut for 36 days. A whole island lost every home on it.
It affected 85,000 people (about 85 per cent of the population), cost the country $90 million, destroyed or damaged more than 600 buildings, and significantly impacted crops, livestock, and fisheries.
The Tongan people will not recover from this quickly and should not be forgotten.
Sources: Tonga Volcano Blasted Out Pressure Waves “Very Close to The Theoretical Limit”, Tonga underwater volcano eruption shattered two records, Underwater Volcano Spit Shock Waves Into Space That Lapped Earth Several Times and Assessing the Aftermath of Tonga’s Volcanic Eruption and Tsunami.
I talked about this with Danny Hoyland on West Bremer Radio on 2 July 2022. Listen live each week: Saturday 7.40 am, West Bremer Radio.