2011 Japanese Earthquake and Tsunami - News and Analysis

chaanakya · Post by **chaanakya** » 25 Mar 2011 23:12

vina wrote:[
You ALWAYS design for a postulated scenario. When you build a bridge over say a sea or something, you look at a 100 year/150 year record to estimate the maximum you design that for. A 35 meter Tsunami has probably never happened EVER in recorded human history!

Are you sure??

Just read a few posts before.
Japan has a history of tsunami wave reaching up to 38 mts.

This bloomberg report says with link to USGS

A 7.6-magnitude quake in 1896 off the east coast of Japan created waves as high as 38 meters, while an 8.6- magnitude temblor in 1933 led to a surge as high as 29 meters, according to the U.S. Geological Survey.

Geologist Masanobu Shishikura, a researcher under Okamura who has focused on the 869 tsunami, said he wasn’t surprised historical evidence wasn’t heeded to. When he presented to government officials from two towns on the coast north of Dai-Ichi, the urgency wasn’t clear even to him.

Today, those towns of Higashi Matshushima and Ishinomaki lie in ruins.

“At the time, we thought it was unfortunate they didn’t take us seriously, but we figured it was just a matter of making a better presentation,” Shishikura said. “If only the tsunami had waited a little longer, we might have been ready.”

2004 Tsunami reportedly reached height of 30-34 mts. 2004 tsunami destroyed coastal town Banda Aceh completely and tsunami penetrated upto 36 km inland. Distance ( arial) from Kalpakkam is 27 km approx. So if 35 mts tsunami, likes of what happened in Japan in 1896 or Indonesia in 2004, were to struck, we would have been unprepared precisely for that reason. No one would have blamed the engineers as there was no history.
Tsunami-2004, when it reached Indian shores its height was about 2 to 6 mts at different places and believe me , even that was a horrifying sight.

Additional searching the google chacha

tells me this

http://en.wikipedia.org/wiki/Tsunami
These phenomena rapidly displace large water volumes, as energy from falling debris or expansion transfers to the water at a rate faster than the water can absorb. Their existence was confirmed in 1958, when a giant landslide in Lituya Bay, Alaska, caused the highest wave ever recorded, which had a height of 524 metres (over 1700 feet). The wave didn't travel far, as it struck land almost immediately. Two people fishing in the bay were killed, but another boat amazingly managed to ride the wave. Scientists named these waves megatsunami.

chaanakya · Post by **chaanakya** » 25 Mar 2011 23:18

Sanku wrote:
Lalmohan wrote:ramana-ji, now do you see why i made that comment about marine drive and 35m tsunamis?
Marine Drive is not in seismic zone 5. Has no known history of Tsunami's or quakes.

Discussing Marine drive is entirely irrelevant an pointless.

Discussing the Eastern sea board at least has merit and comparisons with 2004 Tsunami have already been made, which are very instructive.

Banana, lal chix and Stock market are all quite meaningless to the discussion here and only serve to distract from the more meaningful data points.

Such as studies outlining the extent of health issues caused by radiation, the current levels of radiations and the state of the nuclear plant.

===============

Not to lalbrof but in general

And direct deaths from Chernobyl were only 30, so going by the brilliant wisdom on display, Chernobyl is actually safer than HP roadways?

Is logic ka kya kiya jaaye? I propose we replace HP buses by nuclear reactors used in Chernobyl, after all they have killed fewer people yet.

Are you not violating the moratorium on your posting? sanku ji.

ramana · Post by **ramana** » 25 Mar 2011 23:24

I guess the real issue is are we alive after the mega tsunami. If life still goes on after a mega disaster one needs to not contribute to the mess. In this case the coastal nuke power plants was the contriution knowing there are mega quakes in Japan and large tsunamis experienced in Japan. I guess the combination was not postulated. maybe should have been considered in the recent hearings to extend the operating license of the oldest Unit-1.

The meteorite hitting and causing megatsunami doesnt matter for there is death and destruction beyond a 'little' radiation!

Sanku, If one goes by the epics there were instances of tsunamis on Western india: disappearance of Dwaraka, and the sea swallowing guru's Sandeepeny's son. I think those are allusions of tsunamis.

ramana · Post by **ramana** » 25 Mar 2011 23:25

He is not going to reply to only certain posters.

ramana · Post by **ramana** » 25 Mar 2011 23:27

vina wrote:
ramana wrote:(I helped his grad student for it helped me learn to code FFT in Fortran and got some extra time on the IBM 370 in those days!)
Et tu Brutus! You too went to the Madrassa in those days ? Ah the trusty punch card 370. I think they got rid of that only in the mid 80s !

I thought everyone knew and my soft handling of you!

Kaveri Hostel 141

Sanku · Post by **Sanku** » 25 Mar 2011 23:33

ramana wrote: Sanku, If one goes by the epics there were instances of tsunamis on Western india: disappearance of Dwaraka, and the sea swallowing guru's Sandeepeny's son. I think those are allusions of tsunamis.

This is strictly OT, but werent those events absolute rise in sea levels rather than Tusnami's? But a fascinating perspective to consider for sure.

vina · Post by **vina** » 25 Mar 2011 23:34

Sanku wrote: Marine Drive is not in seismic zone 5. Has no known history of Tsunami's or quakes.

Discussing Marine drive is entirely irrelevant an pointless.

Discussing the Eastern sea board at least has merit and comparisons with 2004 Tsunami have already been made, which are very instructive.

Violating my own mental ignore button. But however this takes the cake and needs to be called.

Chennai is not in seismic zone 5 either! In fact, it probably is in a more stable seismic zone than Mumbai (Much of peninsular india is 2 or max 3) which is closer to faultlines (earthquake in Bhuj, Latur, Iranian/Arabian plate fault line is much closer) to western sea board.

In fact, the chances of a tsunami hitting Mumbai is pretty realistic and Marine Drive is very relevant! Just because you dont know if it, doesn't mean that it doesn't exist. Ignorance is bliss and all that I suppose, but that doesn't stop the bull horn from blowing.

Okay. Before 2004 you probably didn't know the word Tsunami. What if there is a category 5 topping hurricane that hits mumbai and there is 10 meter surge. That is lot more fat tailed than a Tsunami . Will the BARC facilities survive that (hint check what is the flood level they designed for to get some idea).

Your entire question seems to look back on the last event and design for that. But that is like trying to fight yesterday's war. How do you know what the next event is going to look like? How do you predict that/design for that. That is the basic question.

Banana, lal chix and Stock market are all quite meaningless to the discussion here and only serve to distract from the more meaningful data points.

Yawn. Like I said this before, it probably is too difficult to comprehend that kind of randomness (there is a nice book called "Fooled by Randomness" by Nassim Nicholas Taleb, he wrote that before the famous "Black Swan",but the topic and idea is the same, read either of those) and make sense out of your kind of linear thinking . So I wont even attempt to enlighten you on that.

But , Banana, Lal Chix AND Stock market volatility (I make a living out of that kind of stochastic processes,so it is daal-roti for me) is absolutely relevant . Just because you can't get it, doesn't make it less so.

Amber G. · Post by **Amber G.** » 25 Mar 2011 23:35

chaanakya wrote:
Amber G. wrote:Chaankya - Since you suggested me to read your posted article, can I urge you to do the same for the same article you posted.

Also calculate, (really calculate, in stead of asking us to prove that those numbers are not wrong).. read up
what ICRP and the NTLH method these people use. I even gave the term you can google to get your basic research material.

Also Simple points Guru Prabhu raised.. just answer them quantitatively instead of mocking us.

And also apply those numbers and methodologies to see if these are really consistent with actual data..

Say in -
- Extra chance calculated by this method for a person who took one plane trip from LA to NY
- Wild life preserve, right near Chernobyl (Easy to get data, we know radiation there and animal's death rate etc.

Let me post again what I posted years ago in brf (I think some one posted a link from time/newsweek confirming this story) and see if that model explains that -

When western reporters and scientists visited the NK reactor for the first time, they were surprised because the reactor pool building had a hole in the roof above (broken sky-light!) with birds going in and out, and there were frogs in the pool .. radioactive but hopping.

Hope this helps.

GuruPrabhu and Chankya - I am going to post the physics problem I was talking about in physics thread.. quite relevant, IMO
hope you put your answers/comments there.
Does that take away the point that counter data point do exist? I am not sure how anyone can assume that I did not read and comprehend when you simply don't show willingness to do the same.
The basic conclusion that I draw from all this ( without doubting your calculations and conclusions) that the issue is still open and one needs to keep his eye peeled unless one happens toJust go through the paras posted. May be they support either thesis. But that is besides the point. belong to the lobby of pro nuke or green peace.. To err on the side of caution is not wrong.

ps I did read that report long back but then there should be some update.

Just go through the paras posted. May be they support either thesis. But that is besides the point.

/SIGH/
I have heard of of Schroedinger's cat but even that doesn't support both A and B are true: where:
A. 875,000 people died due to Chernobyl
B . 57 deaths
Seriously, it will be helpful (for others) if you can summarize the "point" you are tying to make by actual numbers, and hypothesis/methodology which your article is proposing. TIA

PS - Schroedinger's cat, in case one has not heard the term, is a quantum cat which is alive and dead at the same time.

chaanakya · Post by **chaanakya** » 25 Mar 2011 23:36

ramana wrote: Sanku, If one goes by the epics there were instances of tsunamis on Western india: disappearance of Dwaraka, and the sea swallowing guru's Sandeepeny's son. I think those are allusions of tsunamis.

I have been told ( not verified myself though) that there were references in Sangam literature where Sea swallows land.

btw I think either title shoudl be changed or radiation related posts be transfered to appropriate thread.

So you still visit IITM?

ramana · Post by **ramana** » 25 Mar 2011 23:42

Vina, In 1978* there was a severe cyclone in Arabian Sea that caused a big surge. Lots of damage..

* you might have been in KG or not even born.

I dont get to travel as much as I like. Last I went to IITM was in 1999 and took my family to the old digs. I did many visits to India after that but not IITM.

Amber G. · Post by **Amber G.** » 25 Mar 2011 23:49

...Is logic ka kya kiya jaaye? I propose we replace HP buses by nuclear reactors used in Chernobyl, after all they have killed fewer people yet.

But.. Per Chaankyaji's article it is 850,000 deaths...

One should go swimming in NK reactor pool ..remember those frogs ..should be the proposal. N'est Pa?

Seriously ...Is logic ka kya kiya jaaye?

But seriously, let me ask again - how many people have died due to this NPP radiation.. remember it is called "much much worse than Chernobyl" ..with neutron beam, meltdown .. Have we passed that 850,000 number yet?

Sanku · Post by **Sanku** » 25 Mar 2011 23:52

vina wrote: Chennai is not in seismic zone 5 either! In fact, it probably is in a more stable seismic zone than Mumbai (Much of peninsular india is 2 or max 3) which is closer to faultlines (earthquake in Bhuj, Latur, Iranian/Arabian plate fault line is much closer) to western sea board.

In fact, the chances of a tsunami hitting Mumbai is pretty realistic and Marine Drive is very relevant! Just because you dont know if it, doesn't mean that it doesn't exist. Ignorance is bliss and all that I suppose, but that doesn't stop the bull horn from blowing.
.

Well Vina; do look up where the major fault lines exist. You are hopelessly under informed.

I have posted this a couple of times in Nuke thread already.

http://en.wikipedia.org/wiki/2004_India ... nd_tsunami

Indonesia lies between the Pacific Ring of Fire along the north-eastern islands adjacent to and including New Guinea and the Alpide belt along the south and west from Sumatra, Java, Bali, Flores, and Timor.

There is no such high seismic activity plate in Arabian sea. This is documented fact.

So yes, Japan risks >>>> Eastern sea board >>> Western.

I thought some one aware of stochaistic processes and probabilities would at least check the basics of past seismic activity before making that totally wrong statement.

ramana · Post by **ramana** » 25 Mar 2011 23:54

Also peninsular India has intraplate quakes and not inter-plate quakes.

chaanakya · Post by **chaanakya** » 25 Mar 2011 23:55

Amber G. wrote:
Just go through the paras posted. May be they support either thesis. But that is besides the point.
/SIGH/
I have heard of of Schroedinger's cat but even that doesn't support both A and B are true: where:
A. 875,000 people died due to Chernobyl
B . 57 deaths
Seriously, it will be helpful (for others) if you can summarize the "point" you are tying to make by actual numbers, and hypothesis/methodology which your article is proposing. TIA

PS - Schroedinger's cat, in case one has not heard the term, is a quantum cat which is alive and dead at the same time.

Well I never new that "either" meant "both"

I will refrain from replying to your obfuscation of the issues . Asked for moving radiation related posts to separate place as some have started showing ignorance of natural disasters and /or tsunamis.
Let this thread be that of news about tsunami and quake. In Physics thread we can discuss quantum leap of faith and perhaps God particle.

vina · Post by **vina** » 25 Mar 2011 23:56

chaanakya wrote:
vina wrote:[
You ALWAYS design for a postulated scenario. When you build a bridge over say a sea or something, you look at a 100 year/150 year record to estimate the maximum you design that for. A 35 meter Tsunami has probably never happened EVER in recorded human history!
Are you sure??

No, I am not. That is why I said PROBABLY.

Japan has a history of tsunami wave reaching up to 38 mts.........

......... The wave didn't travel far, as it struck land almost immediately. Two people fishing in the bay were killed, but another boat amazingly managed to ride the wave. Scientists named these waves megatsunami.

See, this is the problem with some half backed off the cuff googling and passing that off as "expertise". I can see why a lot of those See-Near folks stopped posting.

If you grew up in India and hadn't traveled much you probably didn't know the word Tsunami before 2004. However that doesn't mean that no one else in India or certain places in India didn't know if it and teach about it!

Don't ask me how, but I can even after all these years I can do actual calculations to predict wave heights at given locations for postulated conditions.For eg, I can tell you how much the wave height will be if a Tsunami were to hit Norway (theoretically) with its Fjords vs say Chennai with it's beaches.

If you think that a Glacier falling off the coast of Mumbai/Chennai /Indonesia/Iran will trigger a 500ft Tsunami , well, I think the metorite falling will have a far higher probability. About the more realistic thing of an earth quake induced one, any half educated (unless a LMU grad) who took those courses will tell you wave heights and surge levels in 5 minutes with a pencil and paper and bathymetric charts and knowledge of the coastline and shelf . In case you didnt know, the wave height is highly dependent on that and even something places that are just a couple of 100m apart along the coast can see very different wave heights and levels depending on that.

In fact mutliple places would have recorded multiple wave heights depending on that from the same distance from the tsunami. If Fukushima was 12ms, some place close by could have seen maybe just 3 meters, someplace more! There is no one site fits all answer for sizing and design of anything and it is a custom study for site selection and design and everything for every plant.

Sanku · Post by **Sanku** » 25 Mar 2011 23:58

Ramana;

vina wrote: See, this is the problem with some half backed off the cuff googling and passing that off as "expertise". I can see why a lot of those See-Near folks stopped posting.

If you grew up in India and hadn't traveled much you probably didn't know the word Tsunami before 2004. However that doesn't mean that no one else in India or certain places in India didn't know if it and teach about it!

Why is the above "personal insult as substitute for intelligent informed discussion" being allowed Sir?

Amber G. · Post by **Amber G.** » 26 Mar 2011 00:00

Sanku wrote:
Well Vina; do look up ...[some information] You are hopelessly under informed.

I have posted this a couple of times in Nuke thread already.

How about some more looking up from the informed-ones... I have just posted (and posted a few times before.. and hope people keep asking because it is very important)

How many people have died in this NPP due to radiation.. when are you reaching that 850.000 number..( much much worse than Chernobyl)

Sanku · Post by **Sanku** » 26 Mar 2011 00:02

Amber, Ramana-garu has asked me to give you a go by. Just so that you know. Please look up in the previous pages. JFYI, so you know no replies will be forthcoming.

chaanakya · Post by **chaanakya** » 26 Mar 2011 00:02

^^ you have a nice way of qualifying every statement.

A

35 meter Tsunami has probably never happened EVER in recorded human history!

vina · Post by **vina** » 26 Mar 2011 00:03

Sanku wrote: Well Vina; do look up where the major fault lines exist. You are hopelessly under informed.

I have posted this a couple of times in Nuke thread already.

http://en.wikipedia.org/wiki/2004_India ... nd_tsunami

Lets put it this way. My knowledge of these things are NOT from Google /Wikpedia. Suffice to say, I know what I am talking about here. There is a Tsunami threat to the west coast as well in certain locations. Go look up any decent earthquake zone chart of India,along with high risk areas and fault lines (hint, much of himalayas as zone 5, there is a high risk zone just off Balochistan,pretty close to Guj/Mah coast).

So yes, Japan risks >>>> Eastern sea board >>> Western.

Yeah. But western sea board has a pretty singificant risk, maybe less than eastern seaboard, but risk all the same.

I thought some one aware of stochaistic processes and probabilities would at least check the basics of past seismic activity before making that totally wrong statement.

Err, since it is only one liners that you can seem to get, let me repeat the one that gets belted out breathlessly on TV and other ads.

"Past performance does not guarantee future performance. Please read the offer documents carefully"

chaanakya · Post by **chaanakya** » 26 Mar 2011 00:05

^^ No I don't see esp. when ignorance is passed off as expertise and refusal to see other view point and tendency to obfuscate is passed off as pure science and logic.

Sanku · Post by **Sanku** » 26 Mar 2011 00:12

Well Vina; none of what you are saying is backed up by literature such as past history of Tusnami and plate movements, but since according to you Future happens irrespective of past because YOU KNOW.

There is very little that can be discussed.

I can discuss past facts, empirical evidences etc. Not "I KNOW, future and past have no correlation"

Jai ho.

Sanku · Post by **Sanku** » 26 Mar 2011 00:13

chaanakya wrote:^^ No I don't see esp. when ignorance is passed off as expertise and refusal to see other view point and tendency to obfuscate is passed off as pure science and logic.

Sir, that is a understatement. There is pride being displayed that people "dont need to learn, since they KNOW"

Its a hopeless case.

Amber G. · Post by **Amber G.** » 26 Mar 2011 00:17

Sanku wrote:Amber, Ramana-garu has asked me to give you a go by. Just so that you know. Please look up in the previous pages. JFYI, so you know no replies will be forthcoming.

Then sir, why the above reply to me????

And also it will be helpful if reply (don't address to me, just reply to all) a question which has been asked.

How many radian deaths in this NPP? How much greater than 850,000?

vina · Post by **vina** » 26 Mar 2011 00:19

Sanku wrote:Well Vina; none of what you are saying is backed up by literature such as past history of Tusnami and plate movements, but since according to you Future happens irrespective of past because YOU KNOW.

Amazing. In a flash, before I could close something, you had already researched and found that there are "No Plate movements" off the coast in the Arabian sea, that there were no previous Tsunamis (never mind, in fact , there is no recorded memory of a Tsunami in the east coast either before 2004

) and that with all the absoluteness and certainty !

There is very little that can be discussed.

Indeed. It is best that the ignore button comes on again.

I can discuss past facts, empirical evidences etc. Not "I KNOW, future and past have no correlation"

Dude! I know it is beyond hope, but this is NOT a predictable phenomenon. You might not have a Tsunami hit the Indian coast (both east and west) in say the next 500 years! Tsuanmis are pretty rare events in Indian Ocean, even rarer in the west coast, that is the reason why there was no monitoring system before 2004! But it does not mean that just because you put in a monitoring system, you will see a Tsunami for the next 1000 years with 100% certainty!.

Get it?

Jai ho.

Jai ho indeed.

Amber G. · Post by **Amber G.** » 26 Mar 2011 00:32

GuruPrabhu:

3. From this they conclude that at 95% confidence level, there is an excess risk of 0.042 per 100 nGy/hr.

4. It is not .042%, but 4.2% (normalized to an exposure of <8 nGy/hr).

I mentioned NTLH before, the part about 'normalized to' is something... well let me put this way.. no serious scientist think that there is any good ( near100%) validity. Yeah.. there are different models, but as I said before, effects due to doses less than 100 rem (that is 1,000,000,000 nGy!) are very little understood. (At least I will not stick out my neck and claim something)

That's why wild life in Chernobyl, or frogs in NK surprised every one.
This, of course, does NOT mean (before people misunderstand and misquote me) that radiation less than that is safe (by any means). Dosimeters monitors doses of million time less of this value, and there will be forced evacuation when the rate is hundred or thousand time less.
It is just that we don't know have a very good model which works all the time.

My critique:

1. No error bars are presented, so it is difficult to judge the significance of this excess.

2. They report 4 significant figures, so one would be forced to conclude that getting 67-84 nGy/hr is healthier than getting a smaller dose of 44-64 nGy/hr. /big smile/

Yes.. those 4 sig figures (and no error bars) are absurd, (IMO) to put it mildly.

Amber G. · Post by **Amber G.** » 26 Mar 2011 00:51

Shivji et all - There was some discussion about K in human body etc..
You (and others) might already know but just 3 points..

- K and Cs (along with Na etc) are in same periodic column (Similar chemical properties). For human body, their properties are similar (Hence so much fuss about Cs). Human body controls K (and also Na, or Cs), it also absorbs these, if present in environment or eaten, but body can not distinguish between one isotope from the other.

- K40 (radioactive isotope) is primary reason for human radiation. Yes we are all radioactive (unless one is dead for years). Unfortunately there is no (not yet) way to avoid K40's radiation and we live with that low radiation risk.

- One can also calculate (makes nice freshmen physics problem

) the added extra radiation (gamma) one gets by sleeping in a double bed (with some one next). Studies have been published on how many extra cancer deaths it will prevent.

Amber G. · Post by **Amber G.** » 26 Mar 2011 01:44

For me, many seemingly OT or offhand comments are the ones which makes reading this form fun.. causes curiosity and excuse to learn new things...

Thanks.. there are many such which caught my eye...and I did more reading on my own.. just a small sample:

..Chennai is not in seismic zone 5 either! In fact, it probably is in a more stable seismic zone than Mumbai ...
... In 1978* there was a severe cyclone in Arabian Sea that caused a big surge.
...In case you didnt know, the wave height is highly dependent on that and .....

Spent some time googling these.. was fun. Learned a lot too.

Amber G. · Post by **Amber G.** » 26 Mar 2011 02:01

Meanwhile serious leaks..:
High radiation levels at Japanese plant

Two workers hospitalised by radiation from Japan's damaged nuclear plant may be discharged soon, the U.N. atomic agency said, although the exact source of the contaminated water which injured them is a mystery. The men, battling to cool one of the most critical reactors at the plant
..radiation appears to be coming from the highly radioactive fuel core rather than from pools holding spent fuel at the plant which have also given rise for concern.

Lalmohan · Post by **Lalmohan** » 26 Mar 2011 02:07

vinaji, you crack me up!

ambarji - that news came out 'yesterday' in japan, us time is much behind

Amber G. · Post by **Amber G.** » 26 Mar 2011 02:11

^^^Thanks .. (Sorry if already posted) (Just posting so we have some numerical data in archives) From
http://www.world-nuclear-news.org/RS_Ex ... 40311.html
(Quoting in full)

Exposures and progress at Fukushima Daiichi
24 March 2011
Three workers at Fukushima Daiichi have been exposed to higher levels of radiation, while steady progress is made on site and discharges to sea are monitored.

Workers make checks ahead of the
reconnection of external power
Three contractors were installing cables in the first floor and basement of the turbine building of unit 3, having to standing in water that resulted in exposures of around 170 millisieverts to the skin on their legs. Two have been taken to hospital.

The dose is higher than a commonly accepted value of 100 millisieverts for nuclear workers in an emergency situation, but less than the 250 millisieverts temporarily allowed by Japanese authorities. The World Health Organisation, however, said that a limit of 500 millisiverts is an international standard for emergency work.

Another worker suffered an exposure of 106 milliseverts during venting work early in the Fukushima crisis, while six more have been confirmed to have received more than 100 millisieverts - and another between 100 and 150 millisieverts. Tokyo Electric Power Company (Tepco) has not revealed the work these people had been carrying out.

Injection of water to cool used fuel ponds in unit 3 continued today using the fuel pool cooling and filtering system. Tepco said it would consider spraying at other units subject to the conditions of the other units' fuel ponds.

External power has now been connected to all six Fukushima Daiichi reactor units, while some checks are still being made before this can be used. Lights are now on in the control rooms of unit 1 and 3.

Tepco noted that the temperature of the containment vessel of unit 1 had built to some 400ºC, compared to a design value of only 138ºC. However, the strength of the component is such that it can withstand the stresses this imposes, said Tepco, and its structural integrity is expected to be maintained. "There is no substantial problem regarding the containment vessel's structural soundness under conditions of pressure 300 kPa and temperature 400ºC."

Releases to sea

There has been more detailed investigation of radioactive releases to sea, after elevated readings were taken on 22 March. Levels of iodine-131 well beyond normal regulatory limits were found about 330 metres south of the discharge channel of Fukushima Daiichi units 1 to 4. Levels of Caesium-137 were also beyond limits.

North of the Daiichi plant the levels of iodine-131 were lower, but still far above limits. This was joined by caesium-137, caesium-134, tellurium-129 and tellurium-129m.

At the Daini plant about ten kilometres to the south, only iodine-131 was found to be above levels. That plant suffered problems due to the tsunami that followed 11 March's earthquake but all four reactors reached cold shutdown status a few days later with no radiological release.

Local people began evacuation more than ten days ago and this is complete to a 20 kilometre radius. People in a further ten-kilometre zone have been warned to stay indoors. Pills to block the potential negative health effects of iodine-131 have been distributed to evacuation centres.

For perspective ..Exposures above 500 mSv are not allowed even for emergency workers...Above 3000-4000 mSv are life threatening (Ld50 dose is, as has been mentioned here quite a few times, around this - that is, if not treated 50% chance of death within 2 months)

Amber G. · Post by **Amber G.** » 26 Mar 2011 02:17

Liked this essay question from a physics course final exam:

- Misinformation.
"The trouble with most folks isn't so much their ignorance; it's
knowing so many things that aren't so."
-- Josh Billings.

Give three examples of common scientific misperceptions that could people to reach incorrect conclusions on important public issues. Describe what you would tell them to correct their misinformation.

Circle the question, and begin your essay h

Amber G. · Post by **Amber G.** » 26 Mar 2011 02:58

Let me summarize.. if you like you can keep it as a reference.

It is NOT the last word... The numbers in wiki or your favorite sources may and will differ.. and they may differ by a lot.

But these are the number(s) I will use, if I have to make a decision for my family, regarding radiation danger vs other danger in emergency situation. .. (Jump out of window/run or stay and take my chances)

Take it FWIW, and I humbly request folks here, not to take a pot-shot at me (OTOH criticism/comments on the numbers are welcome). There are, IMO no "right" numbers. All units are in mSV. Take these numbers as a guide and a rough guide only.

- Whole-body dose of 1000 mSV (or less) , you probably won’t notice.
(Body will repair most of the damage without ever making you sick)

- Larger doses are worse.

- 2000 mSV - (You’ll get sick, (or may even die). it is called "radiation poisoning" most of your hair
will fall out, nausea and listless. etc ... You may have seen this if you have seen some one undergoing radiation therapy. (usually to kill a cancer). You take this chance if risk justifies the benefit.

- 3000 mSV - Chances of death are about 50%, unless you get blood transfusion etc.
(Many references give 4500 mSV as Ld50 dose)

- 10,000 mSV will kill you within hours.. even medical treatment is unlikely to help.

Of course, amount of time, part of the body, your general health, age, and above all LUCK can and will change this.

Less than 1000mSV there are virtually no symptoms at all
Hope this is helpful..

BTW for gamma rays - To get 1 mSV of radiation, your body must be exposed to approximately 1,000,000,000 gamma rays. ( Just, in case you are listening to these Giger counter clicks)

Also for reference 1mSV = 100 mRem = 10,000 banana equivalent dose.

(Again - by no means the above means that doses less than 1000mSV is safe (or will not cause cancer).. it is just we can't say positively (in statistical way) that it will - we go on side of caution.. normal safe level, even for nuclear plant workers, are in the range of 50 mSV. )

shiv · Post by **shiv** » 26 Mar 2011 06:27

Amber G. wrote: - K40 (radioactive isotope) is primary reason for human radiation. Yes we are all radioactive (unless one is dead for years). Unfortunately there is no (not yet) way to avoid K40's radiation and we live with that low radiation risk.

In modern science the way to prove or disprove the potential carcinogenic effect of K40 would be a prospective trial where you take take two comparable groups of humans - (perhaps 5000 in each group) in a multicenter international trial . Ensure that one group has no K40 at all (this can be done by using djinn science and magic). The other group shall have normal levels of K40. Then observe these groups for 70 to 150 years and see if there is any difference in the incidence of cancer after ruling out the effect of all other known carcinogens.

There are other retrospective methods. But a time machine would be useful for those methods.

Amber G. · Post by **Amber G.** » 26 Mar 2011 07:55

shiv wrote:
Amber G. wrote: - K40 (radioactive isotope) is primary reason for human radiation. Yes we are all radioactive (unless one is dead for years). Unfortunately there is no (not yet) way to avoid K40's radiation and we live with that low radiation risk.
In modern science the way to prove or disprove the potential carcinogenic effect of K40 would be a prospective trial where you take take two comparable groups of humans - (perhaps 5000 in each group) in a multicenter international trial . Ensure that one group has no K40 at all (this can be done by using djinn science and magic). The other group shall have normal levels of K40. Then observe these groups for 70 to 150 years and see if there is any difference in the incidence of cancer after ruling out the effect of all other known carcinogens.

There are other retrospective methods. But a time machine would be useful for those methods.

Makes sense if you were talking about " way to prove or disprove the potential carcinogenic effect of K40"..

But to be clear, in above part, (and most other posts I made about radiation units etc) all I was talking about the fact that we are all radioactive (the amount of radiation can be very precisely measured.. one does not need a trial or a control group, just a simple measuring device /smile/. We also know the gamma rays are coming from, mostly, K40 (we can measure the energy spectrum)

The nature of gamma rays, amount, and other things like, how deep they penetration by skin or other tissue, are very precisely measured/understood.

What is not understood is the carcinogenic effect of this radiation.

As an aside, IOW, when we talk about 1 bed, no effect on health is implied between, say eating a K40 banana and non K40 banana. What is being implied is that radiation dose (full body radiation dose) your body will get, if you eat an ordinary banana, would be about .001 mSv or 1 bed.

This is similar when we say our lawn mover is 6 Horse Power. Horses need not be involved, and we are not talking about if the the lawn mower cuts or eats grass, it just means the lawn mover power is about 4000 Watt.

Hope this is useful to make few things clear.. /smile/.

Also , may be I should have been more precise by adding quote marks around low..as in

"with that "low" radiation risk, (if there is any risk in that radiation)

Just a side remark: Chemically there is no reason to believe that K40 will behave differently than other types of K.

GuruPrabhu · Post by **GuruPrabhu** » 26 Mar 2011 08:02

Amber G. wrote:
shiv wrote: There are other retrospective methods. But a time machine would be useful for those methods.
Makes sense if you were talking about " way to prove or disprove the potential carcinogenic effect of K40"..

I did notice the way in which the topic was obfuscated. But, what was the need for time machine type of impolite nonsense? /smile/

shiv · Post by **shiv** » 26 Mar 2011 08:07

Amber G. wrote:
Makes sense if you were talking about " way to prove or disprove the potential carcinogenic effect of K40"..

AmberG ji you missed the joke in my post

. In fact the post is meant to be funny.

brihaspati · Post by **brihaspati** » 26 Mar 2011 08:31

There is some estimated historical instances of slippages on the western board (due to anomalous uprise and downtrends on the western seaboard around Gujarat. But time frame around 6000, 4500, 3750, 3000, 1800, etc BCE. It could be tsunamis , or earthquakes or even storm surges that change local sedimentation profiles permanently.

One thing about earthquakes. Major known faults are potentially mega-vibrators. But the buildup of stress and their transmission in 3D is a hugely less understood or mapped scene. Micro-faults are constantly being formed and merged or fused. They may not in themselves create tsunamis. On the other hand they may contribute to such phenomena as liquefaction. One danger of the Mumbai basin could be that it is based on rather soft supporting soil. Smaller earthquakes could transfer stress zones in a way that one day might lead to liquefaction.

Paleo-faults are not that well documented as yet - the ones that triggered Latur. As to stock price volatilities - there is a possible relationship to certain earthquake patterns. Curious as to the expert opinion on the nature of this relationship if he knows. On a daily basis stock-volatility experts are unlikely to use the versions I think are relevant for earthquakes. It has to do with asymmetry of response to shocks. [Most stock-volatility practitioners still use the symmetric versions most of the time, even if asymmetry is acknowledged - it appears].

GuruPrabhu · Post by **GuruPrabhu** » 26 Mar 2011 08:37

brihaspati wrote:One danger of the Mumbai basin could be that it is based on rather soft supporting soil. Smaller earthquakes could transfer stress zones in a way that one day might lead to liquefaction.

This sounds serious. Is this a good reason for BARC to be shut down and dismantled immediately? This may be a cheaper option compared to building a 100m tall tsunami wall around Trombay. What is your view? Thanks.

negi · Post by **negi** » 26 Mar 2011 08:48

^ BARC is a small city in itself it is amongst the few (if not the only one) campuses in India which has already been planned for next 100 years, it is moving nowhere.