Just watching tsunami vids on youtube, this one particularly
http://www.youtube.com/watch?v=1ikus_TEaGI
How on earth does a tsunami end? I have been looking on google, and apparently 'the big waves just stop coming'...which I obviously had gathered(

), but does all the water that has come out from the sea, just kinda get sucked back in? Like when the tide goes back in but on a bigger scale? Or does it just stay there and have to be drained?
Sorry for all the strange threads today