Japan Is Anticipating A 9.0-Magnitude Megaquake Within The Next 30 Years
A government report estimates that about 298,000 will die in the worst-case scenario.
By May Vin Ang — 18 Apr 2025, 05:31 PM
Japan, a country well-acquainted with seismic activity, experiences roughly 1,500 earthquakes annually due to its location on the Pacific Ring of Fire
However, experts have been sounding the alarm about a potentially catastrophic event: a megaquake in the Nankai Trough that could strike within the next three decades.
In January, Japan's Earthquake Research Committee raised the probability of a magnitude 8.0 to 9.0 earthquake occurring in the Nankai Trough within the next 30 years to approximately 80%
This stretch of seabed, running along the country's Pacific coast, has historically produced massive earthquakes roughly once every century. The trough has a history of huge earthquakes occurring in pairs.
According to The Japan News, the committee posits that with each passing year since the last major quakes — a 7.9 magnitude earthquake in 1944 and an 8.0 in 1946 — the likelihood of another increases.
The Japan Meteorological Agency discussing the 7.1 magnitude earthquake off Miyazaki Prefecture in August 2024.
Image via The Japan NewsA government report released on 31 March updated projections on the potential disaster, estimating the death toll to be around 298,000
While the death toll was revised slightly downward from a previous estimate of 323,000, the area expected to be flooded by a resulting tsunami after the megaquake has expanded by 30%.
Of the projected fatalities, about 215,000 (or 70%) would be caused by the tsunami alone — which could hit the shore in less than five minutes — particularly in a worst-case scenario where the quake strikes late at night in winter, with only 20% of the population able to evacuate in time.
The latest report estimates that the highest tsunami, measuring 34m, would hit Kuroshio and Tosashimizu in Kochi Prefecture.
Up to 12.3 million would evacuate, 950,000 would be injured, and 2.35 million houses would be destroyed, according to the latest report.
The economic damage is estimated to be 292 trillion yen (about RM9 trillion).
Authorities continue to urge preparedness, warning that the devastation from such an event would be unprecedented in modern Japan.
A wave approaching Miyako City after an earthquake struck the area on 11 March 2011.
Image via Reuters/SCMP