Historical tsunamis · Aug 29, 1741
1741 W. Hokkaido Island tsunami
Japan
The tsunami of Aug 29, 1741 originated near W. Hokkaido Island (Japan).
Key facts
- Date
- Aug 29, 1741
- Cause
- Volcano and landslide
- Magnitude
- M6.9
- Maximum documented water height
- 90.0 m
- Deaths
- 2,000
- Houses destroyed
- 871
- Damage
- severe (about US$ 5–25 million)
- Observation records
- 63
- Countries affected
- 2
Cause according to NOAA/NCEI: Volcano and landslide.
The highest documented water height was 90.0 m (Sado Island, Japan).
63 observation sites in 2 countries are recorded.
The database records 2,000 deaths.
Houses destroyed: 871.
Damage is estimated at severe (about US$ 5–25 million).
Map of observation sites
63Each dot is a documented observation site; colour and size show the observed water height. The triangle marks the source.
Observations by country
| Country | Observation records | Maximum documented water height | Deaths | Earliest arrival |
|---|---|---|---|---|
| Japan | 56 | 90.0 m Sado Island | 1,607 | — |
 South Korea | 7 | 4.00 m Pyonghae | — | — |
Highest documented water heights
15 / 63Individual 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 |
|---|---|---|---|
| Sado Island · Niigata | 90.00 m | 396 km | Japan |
| Gankakezawa · Hokkaido | 34.00 m | 54 km | Japan |
| Shirakami · Hokkaido | 23.00 m | 68 km | Japan |
| Denchizawa · Hokkaido | 20.00 m | 64 km | Japan |
| Satsumae · Hokkaido | 16.00 m | 55 km | Japan |
| Toyooka · Hokkaido | 14.00 m | 63 km | Japan |
| Era · Hokkaido | 13.00 m | 52 km | Japan |
| Chiisago · Hokkaido | 12.00 m | 55 km | Japan |
| Ishizaki · Hokkaido | 12.00 m | 59 km | Japan |
| Ainuma · Hokkaido | 11.00 m | 86 km | Japan |
| Fushikido · Hokkaido | 11.00 m | 79 km | Japan |
| Kiyobe · Hokkaido | 11.00 m | 53 km | Japan |
| Kumaishi · Hokkaido | 11.00 m | 86 km | Japan |
| Narugami · Hokkaido | 11.00 m | 86 km | Japan |
| Ooiso · Hokkaido | 11.00 m | 62 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.