Ride the Tsunami

[arisatx]

Originally Posted by SurferShane

Bet it would have been a lot more exciting if you - or I for that matter - understood Japanese?

http://www.youtube.com/comment?lc=NL...fzkpVY9pcSV6ew

[roverhi]

Mahalo for posting the video with english translation. The ship was 5km/4 miles out to sea when the video was taken. Anybody got any Japanese charts to be able to get an idea of how deep the water was??

[estarzinger]

Originally Posted by roverhi

Mahalo for posting the video with english translation. The ship was 5km/4 miles out to sea when the video was taken. Anybody got any Japanese charts to be able to get an idea of how deep the water was??

Depends where exactly they were - could have been anywhere between 60 - 600' deep.

There is a variable width shelf and then a very deep trench off the Japanese east coast.

[boatman61]

Originally Posted by estarzinger

Depends where exactly they were - could have been anywhere between 60 - 600' deep.

There is a variable width shelf and then a very deep trench off the Japanese east coast.

Doubt it was 60ft.... it would have been a bit more wild and toppling if that shallow...

[S/V Alchemy]

Originally Posted by Saucy Sailoress

Interesting (if a little dull). I noticed that when they reached the crest of the wave, they kept ploughing forward. Now, when we've been in huge seas we would bear away when reaching the crest, to avoid slamming the hull down on the other side and causing damage...

You would indeed in a normal, curling, white-capped topped, wind-driven wave, but that was just like a big swell, with far shallower angles. So there was little chance of burying the boat or of applying so much "stopping" force to the boat (or the hypothetical sailboat's rigging) that any damage or even a splash would occur.

That water was otherwise pretty calm for the ocean.

[S/V Alchemy]

Originally Posted by boatman61

Doubt it was 60ft.... it would have been a bit more wild and toppling if that shallow...

I'd take a 60 foot depth if it was close to a 200 foot cliff edge, because it's the distance and angle of the shelving near the shore that seems to turn the swell into the classic "piled up wave fronts".

Also, any river delta or inlet is going to compress the tsunami's energy into height. Isn't that what threw the boats part way up the mountain in Alaska? The fjord was long, narrow and shelving and aimed squarely at the wave. The water just slopped way up the back of the bathtub.

[capn_billl]

Originally Posted by roverhi

Looks like that video was taken about 7am, 3 hours after the Tsunami hit the Big Island. I was motoring around Kailua Bay just offshore of where the video was taken. Had absolutely no indication of what was going on on shore. I hadn't seen the video, Mahalo for posting it.

Still no answer how deep and under what conditions it's safe to be at sea in a Tsunami. The wave that the ship rode over was way more destructive and higher when it hit shore. There is evidence of a way large Tsunami hitting the East Coast in prehistoric times. Supposedly the fault that caused that Tsunami is off of Africa so should have plenty of warning if it happened again. I'd be looking for information as to how far offshore I'd have to go if I had a boat the right coast.

Knowing where the closest deep water is is a good start. That boat was only 4 miles out. Easily doable with an hours warning. How deep is safe depends on how big the wave.