Effects of the Tonga-Hunga Eruption

(Image not to scale.) The Hunga Tonga-Hunga Ha’apai eruption on Jan. 15, 2022, caused many effects. Some of those effects, like extreme winds and unusual electric currents were picked up by NASA’s ICON mission and ESA’s (the European Space Agency) Swarm. Credits: NASA’s Goddard Space Flight Center/Mary Pat Hrybyk-Keith

On 20 December 2021, an eruption began on Hunga Tonga–Hunga Haʻapai, a submarine volcano in the Tongan archipelago in the southern Pacific Ocean. The eruption reached a powerful climax on 15 January when it sent a tsunami racing around the world and set off a sonic boom that circled the globe twice. 

The underwater eruption blasted an enormous plume of water vapor into Earth’s stratosphere. The plume sent enough water into the upper layers of the atmosphere to fill 58,000 Olympic-size swimming pools. That’s nearly four times the amount of water vapor that scientists estimate the 1991 Mount Pinatubo eruption in the Philippines lofted into the stratosphere.

The height of the plume can reveal how much ice was sent into the stratosphere and where ash particles were released. The height is also critical for aviation safety because volcanic ash can cause jet engine failure.

The Tonga volcanic eruption created a plume of ash and water so strong it reached the mesosphere, about 50-80 km above Earth’s surface, where meteors and meteorites usually burn up. 

Researchers seek to understand the impact the eruption might have on Earth's climate. Massive volcanic eruptions like Krakatoa and Mount Pinatubo typically cool Earth’s surface by ejecting gases, dust, and ash that reflect sunlight back into space. The Tonga volcano did not inject large amounts of aerosols into the stratosphere, and the huge amounts of water vapor from the eruption may have a small, temporary warming effect, since water vapor traps heat.

The eruption of Tonga-Hunga produced a 6-acre island in the Pacific Ocean. The new island is likely to disappear due to volcanic rock degradation caused by the erosion of the waves. According to NASA, islands created by submarine volcanoes are often short-lived, though they occasionally persist for years. For example, an island formed by a 12-day eruption from nearby Late'iki Volcano in 2020 washed away after two months, while an island created in 1995 by the same volcano remained for over two decades.

Related reading: NASA report: "Tonga Eruption Blasted Unprecedented Amount of Water Into Stratosphere"; Volcanic Eruptions and Climate