Japan on Alert: Experts Indicate 82% Probability of Megaquake That May Claim 300,000 Lives

The Japanese authorities caution that a megaquake in the Nankai Trough could result in the loss of up to 300,000 lives unless further preparations are undertaken. In January, a governmental panel increased the probability of such an earthquake to between 75% and 82%.

In March, projections indicated that this earthquake, along with the subsequent tsunami, could lead to damages amounting to $2 trillion and nearly 300,000 deaths. The disaster management plan established in 2014 aimed to reduce fatalities by 80%, but recent revisions indicate that current measures may only decrease the death toll by 20%.

To enhance preparedness, the government advocates for the construction of evacuation facilities, levees, and an increase in disaster response drills. Prime Minister Shigeru Ishiba underscored the importance of collaboration across all sectors to protect lives.

The Nankai Trough, a 500-mile fault line located off Japan’s Pacific coastline, has historically generated megaquakes every 100 to 200 years over the past 1,400 years, with the most recent occurring in 1946. The Japan Meteorological Association (JMA) initially issued a warning in 2024 but retracted it shortly thereafter.

Concerns expressed on social media and a manga foretelling a disaster on July 5, 2025, have led some tourists, particularly from Hong Kong, to delay their travel plans. Conversely, there has been an increase in visitors from South Korea and China.

Ryoichi Nomura, the head of the JMA, highlighted that predicting earthquakes remains unfeasible and called for a composed approach to preparedness.

A similar magnitude 9 earthquake occurred in 2011, resulting in extensive devastation, including the Fukushima nuclear incident. Experts caution that a future quake in the Nankai Trough could be even more catastrophic.