Layers of ash centimetres thick could fall on Auckland - and even on the top of the South Island - if New Zealand's long-slumbering supervolcano had an angry awakening.

The Taupō Volcano, hidden by the water-filled caldera that is Lake Taupō, has produced some of the largest eruptions on the planet.

One of its most recent, the devastating Hatepe event 1800 years ago, spewed more than 120 cubic km of material into the atmosphere and obliterated the landscape surrounding it.

Now, a just-published paper has modelled how much ash would be dispersed in different types of future eruptions.


Ashfall can