Terrawatch: Santorini braces as explosive volcano stirs

It has been quiet for nearly 400 years, but Kolumbo, an underwater volcano just off the Greek island of Santorini, is not asleep. A previously undetected magma chamber is gradually filling with melt, prompting researchers to recommend real-time monitoring of the volcano.

The last time Kolumbo erupted, in 1650, it killed 70 people, but population growth and tourism on Santorini mean the impact of an equivalent eruption today could be far greater.

Kolumbo belongs to the highly explosive family of volcanoes, capable of producing an eruption column tens of kilometres high. It is also liable to trigger a tsunami, making it a highly dangerous prospect. Using a new imaging technique – similar to a medical ultrasound – Kajetan Chrapkiewicz, from Imperial College London, and his colleagues spotted melt gathering roughly two miles beneath the volcano. Their conclusions, which are published in the journal Geochemistry, Geophysics, Geosystems, suggest that although an eruption is not imminent, the volcano poses a serious threat.

Another group of researchers onboard the Joides Resolution research vessel is drilling sediments around Kolumbo to reconstruct its eruption history over the past few million years. Among other things, they hope to understand the links between earthquakes and volcanoes in this region, and to investigate the influence of sea-level change on the size and frequency of eruptions.