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No Tsunami

Did the volcanic eruption on La Palma in the Spanish Canary Islands on September 19, 2021, trigger a tsunami warning in the U.S.? No, that's not true: The National Tsunami Warning Center, part of the U.S. National Weather Service, confirmed that the claim is false.

The claim appeared in an Instagram post on September 22, 2021. The narrator of the video says in part:

First of all, the Canary Islands is bout to blow the fuck up bro. Alright? Alright? Now look at this.

Yeah so basically right, they said that half the island is gonna slide off into the ocean, it's gonna cause a major tsunami. They already put up the picture. Y'all see that shit? They said Florida gonna be underwater: Atlantis! All of the coastline gonna be underwater. New York, Philly, everywhere, Texas, all that shit bro.

This is how the post looked on Instagram on September 24, 2021:

(Source: Instagram screenshot taken on Fri Sep 24 13:30:57 2021 UTC)

The video was reposted on Instagram from TikTok (archived here). While the eruption was real, the graphic the TikTokker used (archived here) to support their claim came from the website of Hal Turner, a convicted felon rated a white supremacist extremist by the Southern Poverty Law Center.

On September 19, 2021, the National Tsunami Warning Center issued a statement that denied the claim:

There is NO tsunami danger for the U.S. East Coast at this time, following the eruption of Cumbre Vieja volcano, La Palma, Canary Islands. The National Tsunami Warning Center is monitoring this situation, and based on all available data, including nearby water level observations, there is no tsunami hazard for the U.S. East Coast.

A reminder, tsunami alerts are disseminated through National Weather Service and broadcast through official pathways including the Emergency Alert System, NOAA Weather Radio, and Wireless Emergency Alerts.

In an email to Lead Stories on September 27, 2021, the National Tsunami Warning Center said:

The ongoing volcanic activity in the Canary Islands is not posing a tsunami risk for the United States or Canada, and the likelihood of it posing a future threat is remote. NOAA's tsunami warning centers are monitoring seismic data, sea-level observations and coastal water level gauges, and will issue alerts if tsunami activity is detected. NOAA issues tsunami alerts via Wireless Emergency Alerts (WEA), the Emergency Alert System, NOAA Weather Radio, tsunami.gov and social media.

With all of the available data from other sources, the three Deep-ocean Assessment and Reporting of Tsunami (DART) buoy stations currently out of service in the Atlantic Ocean will not significantly impact the NOAA tsunami warning centers' ability to issue watches or warnings in the event of a tsunami threat. The remaining four DARTs in the Atlantic Ocean are operating normally.

Additionally, James Waddell, a scientist at the National Tsunami Warning Center, told Lead Stories in a September 24, 2021, phone call that there was "virtually no evidence of anything like that that could possibly happen right now." He reiterated that the U.S. Tsunami Warning System website is the best resource for monitoring U.S. tsunami warnings.

At the time of writing, none of the Warning System's tsunami messages around the time of the volcanic eruption involved tsunami warnings for the U.S.
The Alaskan tsunami message relayed information of an earthquake 95 miles southeast of the state, but clarified that there was no expectation of a tsunami. A screenshot of a list of those messages is below:

(Source: U.S. Tsunami Warning System screenshot taken on Fri Sep 24 13:36:06 2021 UTC)