Japan: maximum volcanic alert since the strong explosion of Sakurajima

On Sunday, a violent explosion occurred at this very active volcano located in the south of the island of Kyūshū, Japan. Rock fragments fell not far from inhabited areas, prompting authorities to raise the volcanic alert level to level 5 out of 5, leading to evacuations.

The many inhabitants of Kagoshima, a city of 600,000 inhabitants located only a few kilometers from the summit of this volcano, are used to seeing ash plumes above the Sakurajima. Indeed, the latter has been erupting since 1955, but the activity there is discontinuous and of variable intensity over time. From May 2021the explosive activity has, for example, gradually decreased and only a few discrete emissions of ashes then animated the volcano from time to time. Then, from the end of January 2022, only one incandescent night could be seen above the Minamidake crater which has hosted most of the activity for several years.

One of the three most powerful explosions of the last twenty years for this volcano!

Explosive activity resumed on June 27, then more frequently from July 17, with ash plumes more than 2 km high and projections falling back into the summit area. A new cycle was therefore beginning.

And then, on July 24, at precisely 8:05 p.m., a powerful explosion occurred. According to Kazuhiro Ishihara, professor emeritus at Kyoto University, it would be ” in the top 3 for the past 20 years ! Projections fell up to 2.5 km from the crater and therefore not far from inhabited areas since the nearest villages are about 4 km from the summit…

If no damage is visibly to be deplored, the local authorities have decided to raise the alert level from 3 to 5, the access prohibition zone thus increasing from 2 to 3 km in radius around the active craters. In fact, the 51 people living in this area had to evacuate…

This is the first time that the maximum alert level has been triggered for this volcano since 2007, when this rating system came into effect. However, on the database monitoring, the volcanologists Japanese believe that there is currently no sign of a large-scale eruption. The last dates from 1914 and had 58 victims.