Analysis - Why is 2023 so hot? A rare Pacific volcano is among the suspects

A grab taken from footage by Japan's Himawari-8 satellite and released by the National Institute of Information and Communications on January 15, 2022 shows the volcanic eruption that provoked a tsunami in Tonga. - AFP

OSLO: As the world swelters through record temperatures, scientists say an unusual culprit may be partly to blame: an underwater volcanic eruption off Tonga in the South Pacific last year.

While most big blasts cool the planet with a sun-dimming haze, the eruption of Hunga Tonga-Hunga Ha'apai in January 2022 blew the equivalent of 60,000 Olympic swimming pools of water into the stratosphere, high above the planet.