how do you know when a tsunami is going to hit?

Answer 1

a tsunami is a series of waves caused by the displacement of water. it is usually the result of a seismic event, such as an earthquake on the seafloor. This would occur at subduction zones, where one tectonic plate is moving under another. the plates may get stuck in one spot and once they release (the earthquake), the water is displaced. for this reason, tsunamis are most likely to occur around subduction zones (such as the pacific). in the atlantic, where there are no subduction zones, a tsunami could potentially occur if there were an event which would cause enough displacement to cause a tsunami. the canary islands have been researched to determine the possibility of a landslide that could cause a tsunami. the idea is that a large landslide could cause enough quick displacement to cause a tsunami. also, a meteor impact would be very effective at causing a tsunami. there are a few other potential causes, but the ones listed above are the most likely.

a tsunami cannot be truly predicted, but knowledge of the usual causes can indicated whether one would be possible. unfortunately, this would not prevent much of the catastrophic effects of a large tsunami. tsunamis move very quickly, so if, for example, there was a large undersea earthquake and a tsunami formed, the tsunami would hit very soon thereafter, making it hard to be prepared (check out the indonesia disaster).

wikipedia has good info on tsunamis, and for this and other earth related questions, geology.com is good.

Answer 2

Tsunamis are very difficult to predict. When they are far out at sea the wave itself is relatively small (a meter or so). Current monitoring systems use buoys to which record information about the waves. Certain combinations of characteristics (wave height, distance between waves, etc) can identify waves that have the potential of becoming a tsunami. They are also caused by more than just earthquakes so monitoring has to be continuous (not just after an earthquake).

Answer 3

The tell-tale signature that a tsunami is going to hit the coast is the sea level will draw down suddenly and become lower than low tide. This often attracts people out to see the tide pools and they will walk out from the shore. The correct response is to quickly move inland when this happens.

Answer 4

The simplest way is to observe the behavior of animals. Although no one knows why, for some reason most animals panic shortly before an earthquake or tsunami. So if you are walking your dog on the beach and he yelps and runs, follow him...

Answer 5

no one knows of course! if you live near sea shores, it is much better to go to high places at once, after an earthquake because there's a big probability of a tsunami to occur.

Answer 6

you can feel it coming it sounds like a roar and the earth will tremble