It depends how far away from land you are. A Tsunami has tons of energy, but it only really gets 'big' on the surface when that energy is constrained by the de

It depends how far away from land you are. A Tsunami has tons of energy, but it only really gets 'big' on the surface when that energy is constrained by the depth of the sea floor. That's why if you're on a boat and get a tsunami warning, it's better to head out to sea.