Precise Timing Cannot Be Predicted
When exactly the Nankai Trough earthquake will occur cannot be predicted by current science. This reflects fundamental limitations in seismic science. The Japan Meteorological Agency's statement—"70-80% probability within 30 years"—expresses long-term probabilistic assessment, not a specific prediction of "next month" or "next year."
Understanding Probability Forecasts
"70-80% probability within 30 years" indicates that over a 30-year timeframe, a major earthquake is likely to occur. This differs fundamentally from weather forecasts like "30% chance of rain tomorrow." Long-term probability estimates guide disaster preparedness priorities but do not predict short-term timing.
Why Prediction Remains Impossible
Earthquakes are chaotic phenomena involving complex, nonlinear processes. Precursory seismic activity and crustal deformation are not reliably detectable beforehand, and detection does not necessarily enable short-term prediction. Leading seismic research institutions globally acknowledge that earthquake short-term prediction remains scientifically unachievable with current technology.