The eruption of the Hunga volcano in Tonga touched the area

When the Hunga Tonga-Hunga Ha’apai volcano erupted in the Pacific Ocean earlier this year, the event was one for the record books — it was amazing in more ways than one.

On January 15, the eruption was so explosive that it ejected water vapor so high that it reached space, the first observation of a terrestrial volcano. And the event is the highest concentration of lightning ever detected — making it far brighter than the 2018 eruption of Krakatau in Indonesia or the 2021 tornado outbreak across the Southern US.

the eruption also released so much energy that its upheaval of the Earth’s atmospheric layer, called the ionosphere, coincided with the solar geomagnetic storm.

Seismologists, geophysicists and oceanographers described this and other superlatives of the eruption in a news conference on December 12 and met with several encouragements at the American Geophysical Union event in Chicago.

“These are once in a lifetime … observations,” said Larry Paxton, an astrophysicist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md.

He and his colleagues analyzed data from NASA’s Global Ultraviolet Imager, a spacecraft in orbit around Earth. On the day of the eruption, Paxton said the instrument revealed “something unusual” in the far ultraviolet part of the electromagnetic spectrum: a round spot in the satellite data coincides with a place on the volcano where there was a temporary decrease in UV light. emissions

The instrument does not see anything in the atmosphere below about 100 kilometers above sea level, what is normally considered the limit of space. This means that some material ejected — likely water vapor from a subsea volcano — reached deep enough into space to briefly absorb those parts of the light that the researchers reported. Previously, scientists estimated that the eruption extended past the stratosphere and into the mesosphere. The new discovery suggests a larger explosion.

The volcano erupted in December 2021 (SN: 1/21/22). Early January is already “one of the most prolific lightning producers” on the planet, said Chris Vagasky, a meteorologist with Vaisala Inc., an environmental instruments company headquartered in Vantaa, Finland.

Using Vaisala’s Global Light Detection Network, Vagasky and colleagues estimate that on January 15 alone, at least 400,000 lightning strikes struck the surrounding volcano — an order of magnitude higher than what is commonly observed in Earth’s thunderstorms, Vagasky said. “This was the highest lightning event ever detected by the global network.”

Some of the explosive energy of the volcano makes it to the ionosphere, a layer of Earth’s atmosphere, where charged plasma coexists with other atmospheric particles. Atmospheric pressure waves from the eruption propagated into space, turning the plasma around (SN: 8/29/22).

Those plasma shifts are then developed along the Earth’s magnetic field lines, resonating through the ionosphere to disturb the plasma thousands of kilometers away. “It’s like picking a guitar string,” said Claire Gasque, a physicist at Berkeley, California. (Gasque is a daughter Science NewsThe news director of Matisco Morehouse was not involved in this article.

In the vicinity of the volcano, which has had an effect on the ionosphere since the eruption of January 15, and has also been overcome, the impact of a minor solar geomagnetic storm that began on January 14, Gasque added. “Despite the simultaneous geomagnetic storm, the volcano was dominated by changes in ionospheric dynamics.”

“Most people think that space weather is caused by solar influences,” Gasque said. But this data suggests that the volcano may have just as much power.

The volcano may yet break other records, researchers said, as scientists continue to collect the most important data from the explosion.