this is a simple paint program reference i made to show the difference between a tsunami and a regular wave
[img][800:328]http://img502.imageshack.us/img502/1120/tsunvsseis.jpg[/img]
the water stays at the same height behind the tsunami for many miles, and the water is actually moving forward. In a regular wave, the water level drops back down very quickly behind the wave, and the water does not move. that is why a cork will just ride over the wave…because the water is not moving forward.

All the video footage I had seen up until yesterday of the Japanese tsunami was kind of boring, because it looked just like raging floods I have seen on TV many times. The water was full of garbage and brown and reasonably slow moving. I have never seen footage of the actual wave as it breaks (while still blue water) until now. Have a look at tsunami1.jpg I attached above, and see that the eye height of the observer is quite high above the sea level (it looks lower at first because he is zooming in). he eventually runs for his life, and many claim he did not make it, but who knows. It seems the water is up to his height at the end.
Also, he shows the actual “breaker” as it rolls in (blue water) and breaks..wow!!
[youtube]http://www.youtube.com/watch?v=2DW1rtWCh_s&feature=related[/youtube]
i must make a new post now because i have hit the "could not obtain smiley data" WALL.
I was just watching that video a week ago.
It's pretty awesome.
Waves, currents, water etc. makes me excited!