Horrendous Earthquake / Tsunami in Japan

[Alex]

Apparently Japan has suffered the worst Earthquake in centuries, which has caused a Tsunami which may affect several other countries.

It's obviously horrible, horrible stuff, with the footage the BBC has shown being absolutely appalling.

More info can be found here: http://www.bbc.co.uk/news/world-middle-east-12307698

I hear the tsunami could affect New Zealand (though right now predictions are unreliable), so hope Mike will be okay...

[SiHart]

The footage of the wave devasting everything in its path that was on the BBC this morning was awful. You can't imagine what destructive power that water has. It was just sweeping across the landscape taking trees and boats and lorries- everything in its path, with it. Awful.

Si xx

[Si Hunt]

It's breathtaking, the force of nature at its strongest. Do you think anything like that will ever happen to us?

Si.

[Rob McCow]

Britain is away from most major faultlines, so it would be unlikely but not impossible.

I can only hope that Japan is well prepared for such an emergency. It's absolutely terrifying.

[Si Hunt]

Apparently they do regular drills to prepare people for earthquakes, but if you protected everything against this you'd be living in a concrete bunker.

Cyndi is in Japan at the moment, but her management report that she's ok. Stephen La Riviere lives out there now, but no-one has heard from him. It's quite incredible, his Facebook pages is flooded with hundreds of messages. The way Stephen talks you'd think he was unliked (he was upset a week or so ago because some people were slating him on a forum - seems a common theme lately), but this suggests the opposite. In many ways it makes me very proud, as there are people posting to his account from all over the place; friends, people you've not heard of, people who work in Cardiff on the TV show, actors... but all just posting to see if one person is ok. It makes me feel part of a family, oddly. Like Doctor Who looking out for its own. Because we're all so tightly connected these days, by things like Facebook. I hope he's alright.

Si.

[SiHart]

New Zealand and Australia are on high alert now, as there's the potential for the tsunami to hit them. Hope they're Ok.

Si xx

[WhiteCrowNZ]

I think it's came and went. Was due to be only a 1m wave hitting us, and hitting at low tide. Last time we had a tsunami after-wash, people went to the beach to see it come in. The stupidity of some people boggles the mind.

A devastating event for Japan. I'd hoped with the massive earthquake being offshore, everyone would have had time to get somewhere safe. But one of the problems is Japan is a massively populous country (twice that of the UK), so any devastation is likely to have an increased toll.

[Rob McCow]

They've admitted that their reactor at Fukushima is close to meltdown. There's already been an explosion. http://www.bbc.co.uk/news/world-asia-pacific-12720219

[Si Hunt]

Mr Kan said the amount of radiation released was "tiny".

"Honestly, it's hardly any. Just a few little bits. There's nothing to worry about."

Si.

[Si Hunt]

How nuclear reactors work

There's a nice diagram and everything.

Argh! I just want to know if I'm going to die a grissly death from radiation as the world blows up in a nuclear inferno, that's all!

Si.

[WhiteCrowNZ]

Argh! I just want to know if I'm going to die a grissly death from radiation as the world blows up in a nuclear inferno, that's all!

Don't worry, there's a guy in charge ...

[Captain Tancredi]

I think it's one thing when an earthquake hits rural China or a single city in an otherwise sparsely-populated country (by British standards) as happened in Christchurch and another when it hits an industrialised and densely urbanised country like Japan. Particularly when you see light aircraft, cars and shipping containers bobbing about in the flood waters. And I'm sure there was a good reason for building nuclear power stations in a seismically active area of the planet at the time, although to be fair I don't know what Japan's natural fuel resources are like.

[Jason Thompson]

IAnd I'm sure there was a good reason for building nuclear power stations in a seismically active area of the planet at the time,

Keep in mind that this is the largest recorded earthquake in Japan's history. The nuclear reactors were built to be safe and shut down in severe earthquakes, and most of them have done precisely what they were supposed to. They have, however, been hit by something bigger than anything previously encountered.

although to be fair I don't know what Japan's natural fuel resources are like.

Japan has practically no natural resources of its own (which was one of the reasons behind their actions in World War II: expand and procure the territory that produces natural resources). If you consider the cost of importing nuclear fuel (which lasts a long time) and regular imports of coal, wood, oil and other things, nuclear power becomes very economically attractive, especially for an industrial economy the size of Japan's.

I hope (possibly in vain) that the media and public will focus on the main issue: getting help to a country now in dire need of it, rather than focusing on the big nuclear bogeyman that has now reared its head.

[Rob McCow]

From 'The Register'.

National strategy minister Koichiro Genba assured there was "no possibility" of a Chernobyl-style disaster, according to local media. Dr Philip Lloyd, a nuclear physicist at Cape Town's Enery Research Institute, told the BBC's World Service that the explosions were "a matter of great concern", but "seen against the totality of the disaster that Japan is facing, I think things are standing up extremely well".

He added: "This is exactly the same as happened at Three Mile Island, when we had a meltdown there but radiation was contained. It seems in this particular case the reactors withstood the seismic event extremely well."

The government has evacuated over 200,000 people from the 20km exclusion zone around Fukushima Daiichi, although there are still "about 475 people in hospitals and nursing care facilities within the radius". Twenty-two people are confirmed to have suffered radiation contamination following Saturday's blast, with as many as 190 exposed.

Quite how much radiation was leaked by the explosions is unclear.

Kyodo reports: "On Monday, radiation at the plant's premises rose over the benchmark limit of 500 micro sievert per hour at two locations, measuring 751 micro sievert at the first location at 2:20 a.m. and 650 at the second at 2:40am, according to the report.

"The hourly amounts are more than half the 1,000 micro sievert to which people are usually exposed in one year.The maximum level detected so far around the plant is 1,557.5 micro sievert logged Sunday."

The US's aircraft carrier USS Ronald Reagan, which had been assisting rescue efforts from a position around 100 miles east of Fukushima, moved "away from the downwind direction of the plant" after it detected "low-level" radiation.

7th Fleet commander Jeff Davis elaborated: "The maximum potential radiation dose received by any ship's force personnel aboard the ship when it passed through the area was less than the radiation exposure received from about one month of exposure to natural background radiation from sources such as rocks, soil, and the sun."

The Daily Mail's headline that it could get a whole lot worse because of the nuclear catastrophe is (surprise surprise) ludicrously overstated. The plants will need to be shut down and there will need to be some level of clean-up, but from the comments it appears that the risk of a catastrophic meltdown is small.

[Si Hunt]

The newspapers seemed to be competing for most dramatic headline over the weekend, most of them bizarrely coming up with great lost Hartnell episode titles in the process. We got "TIDE OF DEATH" and "WAVE OF DESTRUCTION" amongst others.

Si.

[Rob McCow]

It's still not clear how dangerous the nuclear reactor at Fukushima is likely to become.

It appears that for the first time, the containment vessel around one of the Fukushima Daiichi reactors has been breached.

Officials have referred to a possible crack in the suppression chamber of reactor 2 - a large doughnut-shaped structure below the reactor housing. That would allow steam, containing radioactive substances, to escape continuously.

This is the most likely source of the high radioactivity readings seen near the site. Another possible source is the fire in reactor 4 building - believed to have started when a pool storing old fuel rods dried up.

The readings at the site are far beyond safe limits - 400 millisieverts per hour (mSv/hr), when the average person's exposure is 3mS in a year.

A key question is whether this is just a transient spike, which might be expected if number 2 is the source, or whether the high levels are sustained.

In the meantime, the key task for workers at the plant remains to get enough water into the reactors - and, now, into the spent fuel pools - with the poor resources at their disposal.

One aspect of note is that apparently the reactors have survived a disaster way beyond their design capacity without too much radiation leakage so far. This guy at The Register certainly seems to think so - http://www.theregister.co.uk/2011/03...iima_analysis/

I sincerely hope that they are able to get enough water in to cool the reactor cores.

[Si Hunt]

Perhaps the real question is why a disaster of this magnitude IS "beyond their design specification". Yes, it's the biggest earthquake Japan has known, but we know they expect some level of earthquakes because they have early warning systems set up. This is nuclear material! Surely if there's the remotest chance of an enormous earthquake they ought to be able to handle it?!

Si.

[Rob McCow]

It's a question of design life, overall cost and probability. Let's say an Earthquake of magnitude 9.0 happens every 200 years. If the design life of your reactor is 60 years before decomissioning, then you wouldn't necessarily expect a 9.0 to occur. And the costs rise exponentially; it could cost more to build a 10.0 proof reactor than it would to clean up the mess afterwards (possibly, I'm estimating here).

You could say that they should be prepared for that, but then where do you stop? No matter how well you build the reactor, there's always the chance of a bigger earthquake than the one you're prepared for. In this example, the reactors coped well with the earthquakes but seem to have been buggered by the tsunami. As far as I can make out, the issue is purely whether they are able to pump enough water in to cool the core.

[Si Hunt]

You could say that they should be prepared for that, but then where do you stop?

When you make it able to withstand any earthquake?

It's a nuclear reactor!

Si.

[SiHart]

It probably comes donw to expense. If it's more expensive to protect it against a statistically rare event, then they may well have considered it not worth paying out the extra. I suspect in the future this may change, after it's actually happened.

Water seems to be the big problem in Japan at the moment, ironically. Fresh water is in short supply, and most of the areas affected are being supplied by tankers, with it carefully rationed. I imagine this will hampering the efforts to sort out the reactor.

Si xx

[Rob McCow]

When you make it able to withstand any earthquake?

At present, any structure built by mankind could be destroyed by a strong enough earthquake. It doesn't matter how much money or engineering you throw at it, nature can always take it down.

[Jason Thompson]

When you make it able to withstand any earthquake?

Impossible. There is simply no way to design and construct any building that could withstand any conceivable natural disaster or sequence of disasters and retain functionality. Frankly it's pretty impressive it has survived this without simply collapsing. It would have survived the earthwuake fine. They all shut down safely after that. Likewise it would likely have withstood the tsunami. Hit it with one after the other, however, and problems arise. Make it so strong it can survive a magnitude 10 earthwuake followed by a tsunami that swamps the whole country, and what happens if it then gets hit by a downed aircraft or a meteorite? Do we then complain that someone should have forseen that combination of events?

Safety is always a trade-off between risk and probability. Do you refuse to certify a passenger airliner until it is 100% safe? What about a car? Or a crusie liner? 100% safety is an unachievable standard. With hindsight it's easy to say 'well they should have done this'.

It's a nuclear reactor!

Yes it is, and that is nowhere near as bad as many would have you believe. As usual, however, put the word 'nuclear' in anything and rationality disappears out of the window.

I'm not saying this isn't a big problem and a huge danger to the immediate area, I am simply arguing for a little perspective. WHat is the radiation level like half a mile away, for example?

[Si Hunt]

Is it not slightly more easy to predict a tsnuami following an earthquake than a random meteor, given that the latter quite often causes the former?

Si.

[Rob McCow]

Based on past evidence - http://en.wikipedia.org/wiki/List_of...uakes_in_Japan

Estimates of magnitude make it the largest earthquake to hit Japan and among the top five largest earthquakes in the world since seismological record-keeping began.

It was something that had never happened before and, therefore, difficult to predict and prepare for.

[Jason Thompson]

Is it not slightly more easy to predict a tsnuami following an earthquake than a random meteor, given that the latter quite often causes the former?

Yes, but then it's a question of magnitude. Again, this is one of the biggest earthquake/tsunami events in the whole world ever. Instead of being outraged that they haven't survived unscathed, one might be impressed by the fact they have survived as well as they have. One might also bear in mind that they have only started polluting the local environment to any significant degree after one of the biggest natural disasters in history, as opposed to coal fired power stations that do it all day every day as a matter of course.

The bottom line is that some people will always criticise the construction of nuclear power plants when they get damaged, regardless of how unlikely the event that caused the damage actually is. It's the public perception that anything nuclear is the worst thing ever.