Should a tsunami occur and you cannot get to higher ground, stay inside where you are protected from the water. It's best to be on the landward side of the house, away from windows. Often tsunamis occur in multiple waves that can occur minutes apart, but also as much as one hour apart.
If you're too close to powerful tsunami waves, you're at risk of being dragged inshore onto hard land. Just like in drift diving – only much stronger and faster – there is the risk of crashing into underwater structures, being knocked unconscious or sustaining fatal blows.
When a boat is at deep sea, a tsunami just seems like a normal wave which has no effect on the boat itself. A boat near the coast will then be carried inland like anything else onshore.
You can't surf a tsunami because it doesn't have a face. Many people have the misconception that a tsunami wave will resemble the 25-foot waves at Jaws, Waimea or Maverick's, but this is incorrect: those waves look nothing like a tsunami. On a tsunami, there's no face, so there's nothing for a surfboard to grip.
Lituya Bay, Alaska, July 9, 1958Its over 1,700-foot wave was the largest ever recorded for a tsunami. It inundated five square miles of land and cleared hundreds of thousands of trees. Remarkably, only two fatalities occurred.
In some places a tsunami may cause the sea to rise vertically only a few inches or feet. In other places tsunamis have been known to surge vertically as high as 100 feet (30 meters). Most tsunamis cause the sea to rise no more than 10 feet (3 meters).
Try to reach someplace 100 feet above sea level or two miles away from the ocean. If you're lucky, the tsunami will have been caused by an earthquake far away and won't arrive for several hours. Take a disaster kit if you have one on hand, and bring your pets with you.
Once considered mythical and lacking hard evidence for their existence, rogue waves are now proven to exist and known to be a natural ocean phenomenon. A rogue wave is a natural ocean phenomenon that is not caused by land movement, only lasts briefly, occurs in a limited location, and most often happens far out at sea.
Over a hundred adult sharks can be seen just off the shore. Happy news though: improved fisheries management is helping both leopard and white shark numbers to recover along the California coast.
Why does the water level drop before the tsunami hits? Because it is like a tide, the tide goes out before it comes in. As the tsunami approaches water is drawn back from the beach to effectively help feed the wave. In a tide the wave is so long that this happens slowly, over a few hours.
Tsunami currents increase strongly in shallow water where weaker corals can be broken by the force of the tsunami. Fish and marine animals are sometimes stranded on the land after they are carried by the currents to shore. The currents also move sand from the beach onto nearby coral reefs, burying low lying corals.
