• Security incident: ISF was recently accessed by intruders. Please change your password, and change it anywhere else you used it. Read more

Merged 8.8 quake in Sendai, Japan

That's it. They have some stills as well. My stomach lurches at the end just watching it.

I think that's the answer. The wave is so long that you don't ever appreciate the heught from the pictures taken from the shore. At first the crest is so far out you can't get an idea of the size at all, and then the effect is more like the sea-level inexorably rising than an actual wave breaking. The height it rises to is pretty considerable though.

Rolfe.
 
CompusMentus said:
On one particular video (of the Japanese Coastguard ship as it heads into the tsunami in the open sea) I've read that one of the observers on the ship is reported as saying (variously) "it's ten metres! or "it's thirty three feet!". I don't speak Japanese so can't confirm. I also read that this video was shot a few miles off the coast. Tsunami are reputed to gain height as they approach the shoreline so I guess that 13 metres is quite possible.
Compus
Click to expand...
A longer clip from the same footage.
http://www.youtube.com/watch?v=XHitvfd9IUQ&feature=related

Japanese Coast Guard vessel Matsushima, filmed 5 KM off the coast of Soma City, Fukushima prefecture.

You first hear people reporting radar readings and estimates for distance (3.3.miles at first). From time to time distance readings and visual estimates are given in miles and cable lengths. You can hear several people estimate the height of the first wave to be approximately 10 meters when they are approximately 3 miles away. The rest is mostly navigational info - orders and confirmations of orders regarding course, speed of the vessel related to the decision where to ride over each successive wave. The decision is also made to increase speed and head further off shore.

Edit:
Here is another clip. In the info below it is a link for the website of Asahi Shimbun where a lot of other earthquake and tsunami related videos are hosted.
http://www.youtube.com/watch?v=4-mkzcxnJS8
http://video.asahi.com/?tag=ニュース
 
Last edited:
William Parcher said:
I've now seen dozens and dozens of these videos including ones that show the tsunami waves approaching and reaching the shoreline and bay inlets. I've never seen a wave that looked like it was 13 meters high.

The floor of a building is about 3 meters, so a 13 meter wave is a bit taller than 4 floors (stories). That is indeed a big ass wall of water coming.

But what I have seen are considerably smaller waves carrying an immense quantity of water (very wide not tall). I would say that this tsunami brought enormous quantity of water but not any wave constituting "a wall of water".
Click to expand...
A 13 meter tsunami is one that causes a 13 meter surge onshore.
At sea, it can be very small on the surface
for example, the tsunami generated by the Sumatran earthquake was observed by satellite:
The satellites saw the first two wavefronts produced by the main quake, spaced 500 to 800 kilometres apart. These waves reached a maximum height of 50 centimetres in the open ocean, only reaching their full devastating height when entering the shallow waters of the coast.
By comparison, wind-driven waves typically reach 10 metres. However, these waves only involve water close to the ocean surface and are separated by at most several hundred metres.
Tsunami waves have a very deep reach indeed - 4000 metres or more. "These waves involve the entire depth of the ocean. Their energy is thousands of times more than a monster storm," Fu says. And even though tsunamis barely ripple the surface, they speed through the water as fast as jet airliners.
Click to expand...
 
High radiation levels in the ocean: http://www.cnn.com/2011/WORLD/asiapcf/03/30/japan.nuclear.reactors/index.html?hpt=T2#

Tokyo (CNN) -- Radioactive iodine at more than 3,000 times the normal level has been found in ocean water near the crippled Fukushima Daiichi nuclear plant, where workers are struggling to keep reactors cool and prevent radioactive water from entering the Pacific.

Monitoring data collected Tuesday afternoon detected the I-131 isotope at 3,355 times the normal level, according to Japan's Nuclear and Industrial Safety Agency. The sample was taken 330 meters (1,080 feet) away from one of the plant's discharge points, the agency said.
Click to expand...

I thought I heard somewhere the other day thay radioactive iodine only has a half life of 6 days. So if they can fix the leak or whatever it is, the problem would go away in short order, correct?
 
The stupid thing I heard yesterday was an assertion that some isotope or other (might have been I125) only has a half-life of x days, therefore since the earthquake was nearly two weeks ago then levels will have declined a lot by now.

No, idiot journalist, the bloody reactor is still giving off radioisotopes.

And I think there are other isotopes to be concerned about as well as I125.

Rolfe.
 
The Central Scrutinizer said:
High radiation levels in the ocean: http://www.cnn.com/2011/WORLD/asiapcf/03/30/japan.nuclear.reactors/index.html?hpt=T2#



I thought I heard somewhere the other day thay radioactive iodine only has a half life of 6 days. So if they can fix the leak or whatever it is, the problem would go away in short order, correct?
Click to expand...

I read that the half life of radioactive iodine is 8 days. Cesium has a half life of 30 years and may be a greater health risk. But these would be dispersed in the ocean (which still has radioactive byproducts of nuclear testing done in the 1950s and 1960s).

The greater risk is not from the contaminated seawater, but from contamination that gets into groundwater and soil, contaminating food products. This is a problem that would not easily go away, even if the source of the contamination were sealed off.

Bloomberg article here.
 
babycondor said:
I read that the half life of radioactive iodine is 8 days. Cesium has a half life of 30 years and may be a greater health risk. But these would be dispersed in the ocean (which still has radioactive byproducts of nuclear testing done in the 1950s and 1960s).

The greater risk is not from the contaminated seawater, but from contamination that gets into groundwater and soil, contaminating food products. This is a problem that would not easily go away, even if the source of the contamination were sealed off.

Bloomberg article here.
Click to expand...

And then there's plutonium with a half life of something like 6000 years. :eek:
 
babycondor said:
I read that the half life of radioactive iodine is 8 days. Cesium has a half life of 30 years and may be a greater health risk. But these would be dispersed in the ocean (which still has radioactive byproducts of nuclear testing done in the 1950s and 1960s).

The greater risk is not from the contaminated seawater, but from contamination that gets into groundwater and soil, contaminating food products. This is a problem that would not easily go away, even if the source of the contamination were sealed off.

Bloomberg article here.
Click to expand...

Cesium 135 is a particular problem in places with high rainfall and poor soils

In 2009 over 350 UK hillfarms still had restrictions due to Chernobyl
 
I heard they were supposed to encase the entire complex in concrete, like Chernobyl. Wouldn't this tell you that it's going to be a permanent problem there?
 
You must log in or register to reply here.

Share this page

ISF - Join now!

Every member here is approved by hand. No bots, no spam, just people who care about evidence and honest debate.

Membership is free!

Create your free account

Back
Top Bottom