The chances of temporarily exceeding 1.5°C of global warming within the next five years have increased markedly due to the spectacular eruption of an underwater volcano in Tonga in January 2022.
The explosive Hunga Tonga-Hunga Ha’apai event was the most powerful of the 21st century so far. Large eruptions are usually dominated by sulphur dioxide emissions, which cause climate cooling, but the Tonga one was very unusual because …