The next global volcanic disaster is more likely to come from volcanoes that appear dormant and are barely monitored than from the likes of famous volcanoes such as Etna in Sicily or Yellowstone in the US.

Often overlooked, these “hidden” volcanoes erupt more often than most people realise. In regions like the Pacific, South America and Indonesia, an eruption from a volcano with no recorded history occurs every seven to ten years. And their effects can be unexpected and far-reaching.

One volcano has just done exactly that. In November 2025, the Hayli Gubbi volcano in Ethiopia has erupted for the first time in recorded history (at least 12,000 years that we know of). It sent ash plumes 8.5 miles into the sky, with volcanic material failing in Yemen and drifting into air space over northern India.

You don’t have to look far back in history to find another example. In 1982, the little-known and unmonitored Mexican volcano El Chichón erupted explosively after lying dormant for centuries. This series of eruptions caught authorities off-guard: hot avalanches of rock, ash and gas flattened vast areas of jungle. Rivers were dammed, buildings destroyed, and ash fell as far as Guatemala.

More than 2,000 people died and 20,000 were displaced in Mexico’s worst volcanic disaster in modern times. But the catastrophe did not end in Mexico. The sulphur from the........

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