April 11, 1781 Tsunami: SW. Kyushu Island, Japan
A tsunami caused by a volcano began at SW. Kyushu Island, Japan on April 11, 1781. Its effects were recorded at 1 place. It killed 38 people, counting the earthquake or eruption that caused it.
Where the waves reached
The source (white) and every runup with a place, colored by the water height recorded there. A ring is a runup NCEI marks doubtful.
- Under 1 m
- 1 to 3 m
- 3 to 10 m
- 10 to 30 m
- 30 m and more
- Height not recorded
Travel times
How long the first wave took to reach each part of the ocean, one line for each hour up to 24, estimated from the source and the depth of the sea.
The travel times are computed in your browser, which needs JavaScript.
- 1 to 4 hours
- 5 to 6 hours
- 7 to 14 hours
- 15 hours and more
Computed in your browser the way NOAA’s own travel time maps are: the wave travels at the square root of gravity times the depth, over NOAA’s ETOPO1 depths averaged to a 10 arc-minute grid. Checked against NOAA NCEI’s maps for 21 tsunamis over the first 24 hours, these lines fall within 10 minutes of NCEI’s at half the points compared and within 52 minutes at 9 in 10. They give when the first wave could arrive, not how high it is; bays, harbors and island chains finer than the grid can see it later. Not for use in a warning: see tsunami.gov.
The tsunami
- Date
- April 11, 1781
- Source
- SW. Kyushu Island, Japan
- Cause
- Volcano
- Volcano
- The eruption that caused it
- Runups recorded
- 1
- Tsunami intensity (Soloviev-Imamura)
- 1
- Tsunami magnitude (Iida)
- 1
- Waters
- Ocean
- How certain
- Definite tsunami
- Source location
- 31.580° N, 130.670° E
The toll
- Deaths
- 15; 38 with the earthquake or eruption that caused it
- Damage
- Limited (under about $1 million)
Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.
What the record says
NCEI’s account, from the sources it cites.
Reference #150:
1781, April 11. Kagoshima Bay, 31.6 N, 130.7 E. Eruption of Sakurajima Volcano. 15 persons hurt and killed by tsunami.
Reference #414:
1781, April 11. An explosion of the Sakurajima volcano caused a tsunami in Kagoshima Bay (Kyushu Island). Fifteen people died and six ships sank or were damaged. According to Kuno (1962), in November 1779, several small islands were formed off the northeastern coast of Sakurajima Island as a result of underwater eruptions and the elevation of the bottom. Underwater eruptions recurred several times here, accompanied by tsunamis, until early in 1782.
Every runup
Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.
| Where | Country | Km from source | Water height, m | Inland, m | Measured by | First wave, UTC | Deaths |
|---|---|---|---|---|---|---|---|
| Kagoshima Bay | Japan | 10 | Eyewitness observation of water height | 15 |
More
Every tsunami in 1781The 1700sTsunamis of JapanThe eruptionThis day in weather historyAlerts in force
Sources
Tsunami events and runups from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-10-01. NCEI tsunami event 529.