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Experts Warn: Nankai Trough Megaquake Probability Rises to 94.5%

9/27/2025

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Summary

Story summary

The panel revised the 30-year probability of a Nankai Trough megaquake to 60–94.5%.
Naoshi Hirata, panel chairman, said earthquakes are unpredictable and urged ongoing disaster preparedness.
The prior estimate was 80% from Muroto Port data; megaquakes occur every 90–150 years, last in 1946; a magnitude 9 quake could cause 298,000 deaths and ¥292 trillion in losses.

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Story summary

The panel revised the 30-year probability of a Nankai Trough megaquake to 60–94.5%.
Naoshi Hirata, panel chairman, said earthquakes are unpredictable and urged ongoing disaster preparedness.
The prior estimate was 80% from Muroto Port data; megaquakes occur every 90–150 years, last in 1946; a magnitude 9 quake could cause 298,000 deaths and ¥292 trillion in losses.