In order to take appropriate disaster prevention measures in the ever-changing eruption situation when a volcanic eruption occurs, similar past cases are referenced based on various observational data, the mechanism of the eruption is estimated, and the transition is predicted based on that estimation. In particular, volcanic ash emitted from volcanos and transported over long distances is direct evidence of eruptions and holds information essential for understanding the mechanism of eruption occurrence. For example, the presence or absence of magma in the eruption, the state of the magma such as the amounts of crystals and bubbles, and the style of eruption can be estimated from the volcanic ash characteristics which is to say the combination of color, shape, and particle type. However, as no previous database summarized the characteristics of volcanic ash ejected by past eruptions according to a unified standard, it was not easy to investigate similar cases in the past, which was an obstacle to eruption transition prediction that requires immediacy.

AIST released a database of volcanic ash ejected from major eruptions in Japan and abroad. This is the world’s first database that records information such as microscopic images of volcanic ash particles, their eruption styles, and volcanic activity. The database covers most of the volcanic ash from major eruptions in Japan in the 21st century as well as older eruptions and samples collected from eruptions abroad. This database will enable to rapidly search and identify information on past volcanic ash with similar characteristics when a new eruption occurs, which will contribute to the mitigation of eruption disasters by immediately understanding the mechanism of the eruption and predicting its transition.

Volcanic Ash Database: https://gbank.gsj.jp/volcano/volcanic_ash/indexe.php