Tonga eruption's volcanic plume reached above the stratosphere twice

The plume ejected by the Hunga Tonga-Hunga Haʻapai volcano successful January entered the mesosphere, the furniture of ambiance supra the stratosphere, doubly during the eruption

Earth 3 November 2022

By Madeleine Cuff

The elephantine plume of ash, gases and h2o ejected by the Hunga Tonga-Hunga Haʻapai volcano during its eruption successful January was truthful gangly it entered the mesosphere, outer information has confirmed.

The volcanic plume was 57.5 kilometres precocious astatine its peak, the highest ever recorded for a volcano. It entered the mesosphere – which sits supra the stratosphere – doubly during the eruption, erstwhile astatine 4:30 UTC connected 15 January, and again astatine 4:50 UTC the aforesaid day.

The volcano is chiefly underwater successful a distant portion of the Pacific Ocean. It is marked supra the h2o aboveground by 2 small, uninhabited islands. Even so, the eruption killed six people. Loud booms were heard arsenic acold distant arsenic New Zealand and Australia.

“We were precise fortunate that the eruption happened successful a distant place,” says Simon Proud astatine the University of Oxford. “If this had happened determination much populated it would person been incredibly devastating.”

A presumption of the Tonga eruption, 10 minutes aft it started, taken by Japan’s Himawari-8 satellite

Simon Proud / Uni Oxford, RALSpace NCEO / Japan Meteorological Agency

Usually, scientists trust connected the somesthesia of a volcanic unreality – and the surrounding clouds – to cipher however precocious a volcanic plume reaches. But with the Hunga Tonga-Hunga Haʻapai eruption the plume was excessively precocious for this method to work.

Instead, Proud and his colleagues utilized outer information and the parallax effect, wherever the nonstop determination of objects tin displacement according to wherever they are viewed from, to assistance cipher the nonstop tallness of the plume.

“We’re utilizing images from a fewer antithetic upwind satellites that each look astatine a antithetic space astatine this volcano,” helium says. “If you person antithetic estimates from antithetic angles, you tin fig retired the tallness precise exactly.”

The findings confirm a NASA investigation published successful February, which utilized lone 2 satellites and suggested the eruption was 58 kilometres precocious astatine its peak. Proud says the latest appraisal is much robust.

Volcanic eruptions that scope the mesosphere are incredibly rare, and this is the archetypal clip scientists person been capable to corroborate an occurrence. The past eruption connected this standard is apt to person been the 1883 eruption of Krakatoa.

Proud says this caller method of measuring volcano plume tallness could besides beryllium utile to measure the tallness of tempest clouds arsenic they stitchery steam, and truthful estimation their severity.

More connected these topics:

• volcano