Just Cruises Plus

Are Ships Safe During a Tsunami?

Yesterday’s huge earthquake (the 5th  largest in the past 110 years) created a monster tsuanmi which will be felt to some degree (very slight to devastating) all around the world. What effect does a tsunami have on ships?  If the ship is at sea, there is virtually no effect. Even if the ship is close to the epicenter of the earthquake, the tsunami would be hardly noticed.

Things would be much different for folks near shorelines, even if they are thousands of miles from the quake’s center. The ocean could come on shore for several miles in low lying areas.   When an earthquake happens,  an enormous volume of water is displaced by the sudden movement of plates deep below the ocean.   This huge amount of water (used to be called a tidal wave) leaves the spot of the quake  As the water  leaves the spot of the quake,  it is very long and deep but not high (only a few feet above normal)  and would hardy be noticeable on a ship.

However, as the volume of water approaches the shore, the ocean becomes shallow.  All that water has to go somewhere and the only place it can go is up.   What was only a few feet rise in the ocean may become a wall of water upwards of 50 feet as it goes ashore.  This is why ships leave port when a tsunami is expected.

You may be certain that the Poseidon (Poseidon Adventure) did not turn turtle as a result of a tsunami.  It turned turtle as a result of Hollywood fantasy.