March 1, 1820 Eruption of Westdahl
Westdahl in the United States erupted on March 1, 1820 with a Volcanic Explosivity Index of 2. It caused a tsunami.
Where it erupted
Westdahl, United States.
The eruption
- Date
- March 1, 1820
- Volcano
- Westdahl, stratovolcano
- Country
- United States
- Volcanic Explosivity Index
- 2, moderate (eruption column 1 to 5 km)
- Tsunami
- Yes: the tsunami it caused
- Earthquake
- Yes: the earthquake with it
- Location
- 54.516° N, 164.650° W
The toll
The record gives no deaths, injuries or damage for this eruption.
What the record says
NCEI’s account, from the sources it cites.
1820 explosive eruption of Pogromni or (more likely) Westdahl, VEI 2. Westdahl is a broad, 1654-m-high glacier-covered volcano occupying the SW end of Unimak Island. Two peaks protrude from the summit plateau, and a new crater formed in 1978 cuts the summit icecap. The broad volcano has a somewhat of a shield-like morphology and forms one of the largest volcanoes of the Aleutian Islands. Some of the historical eruptions attributed to the eroded Pogromni volcano may have originated instead from Westdahl (Miller et al. 1998). The first historical eruption of Westdahl occurred in 1795. (reference #2432)
1820, March 1 or the night of 2-3. 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 (Reference #414).
More
Every eruption in 1820The 1800sWestdahlEarthquakes near WestdahlThis day in weather history
Sources
Volcanoes and significant eruptions 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. Volcano numbers are the Smithsonian Institution’s Global Volcanism Program’s. NCEI event 5044.