A man on the social platform X has shared an eerie viral video from his cruise ship en route to Alaska after warnings were issued about tsunamis in the Pacific Ocean.

Eric Spracklen, an Ohio-based digital strategist, quote-tweeted an alert about the 8.0 earthquake—which was later upgraded to an 8.8—off the coast of Russia that prompted tsunami alerts in Japan, Hawaii, Russia, Guam and Alaska.

“I’m on a Royal Caribbean cruise to Alaska literally right now,” Spracklen wrote.

“Should I be worried?”

Spracklen’s eerie video accompanying his post showed a misty grey ocean with low visibility, but no apparent swells.

Cruise Ships at Risk?

The answer to Spracklen’s question was actually “no”—cruise ships in the open ocean are generally not at risk from tsunamis.

The main danger from a tsunami is its massive wall of water and force as it approaches shallow coastal areas. In the deep ocean, however, a tsunami is typically only a few feet high and can pass beneath large vessels without being noticed.

The wavelength of a tsunami can stretch hundreds of miles, so a cruise ship riding it in the open sea may only feel a gentle rise and fall, similar to ordinary swells.

‘My advice to you’

Social media commentators were quick to point out that Spracken was relatively safe where he was.

“A ship that size is the safest place you could possibly be,” one person reassured.

“In the open ocean it’ll be barely noticeable,” another user offered, “In shallow water, it’ll pile up against the bottom and be significantly higher.”

Finally, one contributor chipped in with some friendly words: “My advice to you is to start drinking heavily.”

The Real Danger

In a message to Newsweek, Spracklen said he didn’t feel anything more than normal.

“The crew wasn’t too worried about it overall, so it was business as usual,” he added, “Definitely felt safe with Royal Caribbean!”

The real risk comes when ships are near shorelines or in harbors, where the wave’s energy becomes concentrated as the water shallows. For this reason, when tsunami warnings are issued, ships in port may be directed to move out to deeper water where they are much safer.

On land, the tsunamis are far more threatening. A woman in Hawaii shared another eerie video of tsunami sirens going off, in addition to a number of iPhones in her building warning owners of the incoming risk.

She later shared another video saying, “so far, so good and everyone is safe.”

Tsunami waves of up to 3.6 feet reached California, while Hawaii saw water pull back by as much as 30 feet, although no significant damage was reported.

The U.S. Geological Survey estimated that damage from the tsunamis could reach the billions.