Historical tsunamis · May 23, 1938, 7:18 AM UTC
1938 Japan Trench tsunami
Japan
The tsunami of May 23, 1938, 7:18 AM UTC originated near Japan Trench (Japan).
Key facts
- Date
- May 23, 1938, 7:18 AM UTC
- Cause
- Earthquake
- Magnitude
- M7.1
- Maximum documented water height
- 0.83 m
- Observation records
- 7
- Countries affected
- 1
It was triggered by a magnitude 7.1 earthquake.
The highest documented water height was 0.83 m.
7 observation sites in 1 countries are recorded.
Map of observation sites
7Each dot is a documented observation site; colour and size show the observed water height. The triangle marks the source.
Tsunami arrival times
Documented arrival times from the NOAA/NCEI database, showing the earliest recorded location per country. Coverage is incomplete: a country without an entry was not necessarily spared.
- 0:00 hEarthquake (origin) · May 23, 1938, 7:18 AM UTC
- 0:14 hJapan · Ishinomaki · 0.05 m
6 places with a documented arrival time
Observations by country
| Country | Observation records | Maximum documented water height | Deaths | Earliest arrival |
|---|---|---|---|---|
| Japan | 7 | 0.42 m Onahama | — | 0:14 h |
Highest documented water heights
7 / 7Individual documented observations for this event. Heights come from different measurement types and sources; not every location has a measured height.
| Location / station | Observed height | Distance from source | Country |
|---|---|---|---|
| Onahama · Fukushima | 0.42 m | 52 km | Japan |
| Hanabuchi · Miyagi | 0.23 m | 177 km | Japan |
| Onagawa · Miyagi | 0.16 m | 192 km | Japan |
| Hachinohe · Aomori | 0.11 m | 426 km | Japan |
| Choshi · Chiba | 0.09 m | 116 km | Japan |
| Tsukihama · Miyagi | 0.07 m | 207 km | Japan |
| Ishinomaki · Miyagi | 0.05 m | 191 km | Japan |
More tsunamis
Source: NOAA National Centers for Environmental Information (NCEI), Global Historical Tsunami Database. Confirmed events only. Deaths and damage are database estimates; older records are incomplete. Water heights come from different types of observation.