Tsunami in Japan

[Mich the Tester]

Could it happen here?

Could an even bigger disaster strike us???

Unlikely, but Britain and the Netherlands could be bit by a similar storm surge to the 1953 floods, and despite the improved flood defences it might make a bloody huge mess, especially seeing as the low lying areas (London, Amsterdam, Rotterdam) are so densely populated.

[VectraMan]

A tsunami in deep water might only be a foot high. The wave rises rapidly as the water become shallow and approaches land.

So get in a boat and head out to deep ocean water.

If I remember high school physics correctly, a tidal wave (back then we were still allowed to say "tidal wave") has a very long wavelength and small amplitude, so you'd barely notice it out at sea. It's only when the depth of the water becomes less than wavelength that it starts to break and turns into a thirty foot high wall of water.

[Mich the Tester]

If I remember high school physics correctly, a tidal wave (back then we were still allowed to say "tidal wave") has a very long wavelength and small amplitude, so you'd barely notice it out at sea. It's only when the depth of the water becomes less than wavelength that it starts to break and turns into a thirty foot high wall of water.

A tidal wave and a tsunami are quite different.

The Severn bore is a tidal wave. The 1953 storm surge was another kind of tidal wave. A tsunami has nothing to do with tides; it's caused by the earth wobbling about in an earthquake.

[DimPrawn]

If I remember high school physics correctly, a tidal wave (back then we were still allowed to say "tidal wave") has a very long wavelength and small amplitude, so you'd barely notice it out at sea. It's only when the depth of the water becomes less than wavelength that it starts to break and turns into a thirty foot high wall of water.

Yep. Probably nearer to an inch high rather than a foot high, travelling at 500 mph, you'd hardly notice it.

[EternalOptimist]

If I remember high school physics correctly, a tidal wave (back then we were still allowed to say "tidal wave") has a very long wavelength and small amplitude, so you'd barely notice it out at sea. It's only when the depth of the water becomes less than wavelength that it starts to break and turns into a thirty foot high wall of water.

we'll know soon enough. it will be heading for wake, midway the aleutians, alaska and hawaii then the west coast

[d000hg]

Why was Christchurch so bad? From what they're saying on the news so far it seems buildings haven't been that badly affected by the earthquake, and it's the tsunami that's causing the damage. Surely New Zealand being a fairly wealthy country with earthquakes would have had the same sort of earthquake proof buildings as Japan?

The Christchurch one was pretty unremarkable, except that it happened so close to the city. Since effects reduce with square (I guess) of distance, you need only a small quake directly on-target, or a thumping massive one to get the same effect from hundreds of miles away.

They probably don't have that many aircraft, and little boats aren't going to have much of a chance. If the highest point on your island is only 5-10m above sea level you're basically fooked aren't you.

A tsunami in deep water might only be a foot high. The wave rises rapidly as the water become shallow and approaches land.

So get in a boat and head out to deep ocean water.

WHS. Regardless of wave size, it's the breaking water that will swamp your boat. If you can get deep enough that the wave isn't breaking, you just go over the top exactly like when trying to launch your boat off a beach in surf.

[Mich the Tester]

Live coverage on the beeb; BBC News - Japan tsunami

Just saw a supermarket with goods falling off the shelves, all staff running about in a panic except for three obviously well trained and responsible employees who took it upon themselves to hold the wine shelves up. An exemplary display of decision making under pressure.

[Spacecadet]

8.8 reported now. But yikes. I only found out because Google.com has it on their homepage as an announcement.

Does it make me a total scumbag I hope they get better footage than of the tsunami a few years back? Part of me simply wants to watch awestruck at HD video of what nature can do.
I also want to see video of buildings surviving a huge quake, to show how impressive the engineering is.

Wikipedia has a good photo of the oil refinery fire

[doodab]

Interesting article on tsunamis here:

Tsunami

If you are on a boat or ship and there is time, move your vessel to deeper water (at least 100 fathoms). If it is the case that there is concurrent severe weather, it may safer to leave the boat at the pier and physically move to higher ground.

That's about 200m. Just having a look at google earth to see how far I'd have to row if I was Fijian.

Edit: If you are lucky, 5-10 miles. If you're unlucky, about 80, based on a few random samples.

[Mich the Tester]

Interesting article on tsunamis here:

Tsunami



That's about 200m. Just having a look at google earth to see how far I'd have to row if I was Fijian.

Fiji has mountains; much safer.