March 1, 1820 Tsunami: E. Aleutian Islands, AK, United States
A tsunami caused by a volcano began at E. Aleutian Islands, AK, United States on March 1, 1820. Its effects were recorded at 1 place.
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
- March 1, 1820
- Source
- E. Aleutian Islands, AK, United States
- Cause
- Volcano
- Earthquake
- The earthquake
- Volcano
- The eruption that caused it
- Runups recorded
- 1
- Tsunami intensity (Soloviev-Imamura)
- 0.5
- Waters
- Ocean
- How certain
- Questionable tsunami
- Source location
- 54.520° N, 164.650° W
The toll
The record gives no deaths, injuries or damage for this tsunami.
What the record says
NCEI’s account, from the sources it cites.
March 1 or the night of 2-3, 1829. A powerful volcanic eruption occurred on the northern tip of Umnak Island. The ashes spread as far as Unalaska and Unimak Islands. The eruption was accompanied by a strong earthquake. "At dawn, it was observed that the sea had become more agitated". (reference #414)
The eruption of Pogromni Volcano caused a highly disturbed sea, but there were no specific reports of a tsunami. The eruption was accompanied by a strong earthquake, and ashes injected into the air were observed as far away as Unalaska and Umnak Islands. (Ref #239)
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 |
|---|---|---|---|---|---|---|---|
| Umnak Island, AK, AK doubtful | United States | 287 | Eyewitness observation of water height |
More
Every tsunami in 1820The 1800sTsunamis of United StatesThe earthquakeThe 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 2026-09-24. NCEI tsunami event 631.