Japan Issues Level 3 Alert for Shinmoedake Volcano Amid Increased Tremors
Shinmoedake volcano in Japan raised to Level 3 alert due to 200 tremors detected in 24 hours. The Japan Meteorological Agency noted increased seismic activity and ground deformation. Residents near the volcano are warned to stay away and prepared for potential ash fall.
On March 30, 2025, Japan’s Shinmoedake volcano was elevated to a Level 3 alert due to over 200 recorded volcanic tremors within 24 hours. This stratovolcano, part of the Kirishimayama group, had been on a Level 2 alert since December, which previously limited access to its crater. The Japan Meteorological Agency (JMA) observed heightened seismic activity directly beneath the crater as tremors intensified.
The JMA documented instances of up to 10 tremors in an hour, highlighting significant volcanic unrest. Ground deformation indicative of the volcano’s inflation began around 02:50 local time, accompanied by a series of volcanic tremors lasting approximately 10 minutes. Satellite imagery supports these findings, showing gradual inflation since November of the prior year.
Officials expressed concern that a volcanic eruption could propel ballistic projectiles up to 4 km (2.5 miles) from the crater and generate pyroclastic flows reaching about 2 km (1.2 miles). Additionally, volcanic ash could be carried by wind to distant regions, potentially causing structural damage from air shock waves during an explosive eruption.
Residents in Miyakonojo, Kobayashi, Ebino cities, and Takaharu Town in Miyazaki Prefecture, as well as Kirishima City in Kagoshima Prefecture, have been warned to steer clear of the crater area. The last eruption in the Kirishima range occurred on June 27, 2018, with no eruptions since.
Authorities are advising those living downwind to remain vigilant for volcanic ash and small rockfalls resulting from ongoing activity. Emphasis was placed on the need to remain away from the mountainside and to keep windows shut, recalling the significant damage and injuries that arose from the 2011 eruption due to powerful air vibrations.
The Kirishimayama volcanic complex includes more than 20 Quaternary volcanoes across a 20 x 30 km area. Notable types of volcanic structures present include stratovolcanoes, pyroclastic cones, maars, and shield volcanoes. Historical eruptions in this region have been largely concentrated between Miike and Ohachi and at Shinmoedake, with records of frequent explosive eruptions dating back to the 8th century.
The Shinmoedake volcano’s Level 3 alert reflects significant seismic activity and ground deformation, indicating a heightened risk of eruption. Residents in surrounding areas have been advised to take safety precautions and avoid proximity to the volcano. Historical patterns of eruptions and geological observations underscore the need for vigilance in the region.
Original Source: watchers.news
