Scientists Still Baffled by ‘Once-in-a-Lifetime’ Tonga Volcano Eruption

by Sean Griffin

When an undersea volcano erupted in Tonga in January 2022, its blast and its effects have baffled scientists, who recently released reports from their research, according to AP News.

The volcano called Hunga Tonga-Hunga Ha’apai shot millions of tons of water vapor into the atmosphere.

This is according to a study published Thursday in the journal Science.

Researchers estimate the eruption raised the amount of water in the stratosphere by around 5%.

Scientists are trying to discern how all the water could affect the atmosphere; moreover, they’re trying to see how it might warm the Earth’s surface over the next few years.

“This was a once-in-a-lifetime event,” said lead author Holger Voemel. Voemel is a scientist at the National Center for Atmospheric Research in Colorado.

Large eruptions usually cool the planet because most volcanoes shoot large amounts of sulfur in the air. This in turn normally blocks the sun’s rays Matthew Toohey explained. Toohey is a climate researcher at the University of Saskatchewan. He wasn’t involved in the study.

The Tongan blast was much wetter blast. The eruption started under the ocean, so it shot up a plume containing much more water than normal.

Since water vapor acts as a heat-trapping gas, the eruption will most likely raise temperatures instead of lowering them, Toohey said.

However, we don’t know just how much warming may occur.

Scientists Assess Volcano’s Impact

Karen Rosenlof is a climate scientist at the National Oceanic and Atmospheric Administration. She was also not involved with the study, but she expects the effects to be minimal and temporary.

“This amount of increase might warm the surface a small amount for a short amount of time,” Rosenlof wrote in an email.

The water vapor will stick around the upper atmosphere for a few years. Then, it’ll make its way into the lower atmosphere, according to Toohey. In the meantime, the extra water might also speed up ozone loss in the atmosphere, Rosenlof said.

However, scientists don’t know for sure because they’ve never seen a volcanic eruption like this one.

The stratosphere stretches from around 7.5 miles to 31 miles (12 km to 50 km) above Earth. Normally, it’s very dry, Voemel explained.

However, Voemel’s team estimated the volcano’s plume by using a network of instruments. These instruments were then suspended from weather balloons.

Another research group also monitored the blast by using an instrument on a NASA satellite. In their study, which was published earlier this summer, they estimated the eruption to be even bigger. They added around 150 million metric tons of water vapor to the stratosphere. This is an astonishingly larger amount—three times as much as Voemel’s study found.

Voemel acknowledged that the satellite imaging could’ve seen parts of the plume the balloons couldn’t.

Regardless, he said, the Tongan blast will likely affect us and our understanding of our atmosphere.