Japan issues first-ever alert over risk of Nankai Trough megaquake

The Japan Meteorological Agency (JMA) has issued its first-ever alert regarding the risk of a megaquake in the Nankai Trough, following a magnitude 7.1 earthquake off the coast of Kyushu. The alert indicates an increased likelihood of a significant earthquake occurring in the region, although it does not predict a specific timeframe for such an event. The alert is set to remain in effect for one week, and residents are advised to remain vigilant even after it is lifted. The JMA issues alerts based on abnormal seismic activity, with two levels of warnings: the current alert level, which calls for preparedness, and a higher warning level that would necessitate immediate evacuation for those unable to evacuate quickly. The agency noted that the probability of a large quake has increased significantly, with historical data suggesting such quakes occur approximately every century. The last major quake in the Nankai Trough was in 1946. In anticipation of potential seismic activity, Central Japan Railways has already begun operating trains at reduced speeds, resulting in delays. The agency warns that a major earthquake could lead to severe shaking across a wide area and potentially high tsunami waves along the Pacific coast.

- Japan issues its first alert for a potential megaquake in the Nankai Trough.

- The alert follows a magnitude 7.1 earthquake near Kyushu.

- Residents are urged to prepare for possible evacuations.

- The probability of a significant quake has increased, with historical occurrences every 100 years.

- Precautionary measures, including reduced train speeds, have already been implemented.