Scientists continue monitoring climatic and atmospheric effects of Hunga Tonga eruption

More than four years after the massive underwater eruption of the Hunga Tonga–Hunga Haʻapai volcano, debate continues over its long-term impact on Earth’s atmosphere and global temperatures.

The January 15, 2022 eruption in the South Pacific was one of the most powerful volcanic events in modern history. Unlike most major eruptions, which tend to cool the planet by releasing sunlight-blocking aerosols, Hunga Tonga blasted an enormous volume of seawater high into the stratosphere. Scientists estimated the eruption injected around 160 million metric tons of water vapour into the upper atmosphere, increasing stratospheric moisture levels by roughly 10 percent.

Water vapour is considered the most abundant “greenhouse gas” in Earth’s atmosphere, and researchers noted shortly after the eruption that the unusual event could temporarily contribute to global warming. Agencies including NASA previously warned the eruption may have a short-term warming influence because of the unprecedented amount of water vapour reaching the stratosphere.

Experts say rising global temperatures during 2023 and 2024 may have been significantly influenced by the eruption rather than solely by “carbon dioxide emissions”. Excess water vapour slowly declines, global temperatures are beginning to ease.

Climate scientists have acknowledged the eruption likely contributed a warming effect. Studies examining the eruption’s impact are ongoing, with scientists continuing to track atmospheric moisture levels and global temperature trends to determine how large a role the volcanic event may have played.

Hunga Tonga is still affecting the atmosphere.

On January 15, 2022, the underwater volcano erupted in the South Pacific. It blasted roughly 160 million metric tons of water vapor into the stratosphere, increasing levels by an unprecedented 10%.

Most major eruptions cool the… pic.twitter.com/QkPGSLlYOT

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