Predictions for emission duration
How long do people think the emissions from Fukushima will continue?
I read one report today that it will take months to stop the leaks and years to keep pouring water on the cores before then can be entombed/dismantled.
If we are looking at months-long duration (Chernobyl took 7 months to finish the sarcophagus) what would our cumulative fallout look like? We got a fair amount over the last two weeks. If it was to continue at a slower pace, would SF ultimately be as contaminated at the worst parts of Europe?
Thanks
The fallout in CA so far is
The fallout in CA so far is 10% of what it has been over central europe after chernobyl (based on NUC data), while the same amount as chernobyl has been emitted from Fukushima (ZAMG estimates). The four critical reactors at Fukushima have about ten times more fuel than reactor 4 in Chernobyl had. So if they all gas out everything they have in them the deposition here will be the same as in central europe after chernobyl, i.e. several kBq/m^2 of long-radiating Cesium.
I personally don't think there will be a solution to this problem any time soon, since the Japanese are being left alone to figure this one out and the international community of specialists doesn't want to get their fingers dirty. We know already that the Japanese don't have a solution, so it'll probably only stop once all the nuclear fuel has has evaporated or washed into the sea, which could take a couple weeks or months.
As a comparison, please
As a comparison, please could you tell me how the fallout amount over CA to date compares to 5% of Chernobyl's fallout?
2 times it would appear.
2 times it would appear.
I can't answer how long it
I can't answer how long it will last, but Dr. Hermann Jakobs is predicting 0.5-1.0 Bq/m2 per day of dry deposition and around 2.5 per day should it rain. Ignoring I131 as it decays quickly, should it rain 25% of the time for the next month we would be adding around 60 Bq/m2 of CS-137.
At that rate it would take 5-6 months before we would approach some of the more contamined places like Southern Germany.
And that assumes rates stay constant and rain at 25% which is unlikely once we hit May.
Someone please check my math.
If I were a wine producer, I might start to think about foregoing my crops this year.
I think your numbers make
I think your numbers make sense. However note that the daily deposition during the last couple of weeks was higher, due to the amount of rain, probably closer to 8 Bq/m^2 each day of Cesium-137.
Also note that this could easily last 6 months, since there is absolutely no hing of a plan to contain it and the international "community" choses to not help the Japanese.
You mention grapes, and I was trying to remember which crops were most affected after Chernobyl (I am from Southern Germany). I was only 9 years old but seem to recall that fruit that were further from the root system, such as Apples, had least or zero contamination while leafy vegetables, which are directly at the roots, were bad. I don't know where wine grapes would fall in that scheme.
Also, I don't remember if it got much better in the second year for leafy greens, milk, etc. Does anybody else from Europe remember?
Just wondering if I'll ever be able to enjoy pure CA grown organic vegetables again without worries.
Data/Figures
Where are you getting the data/predications of Dr. Jakobs for dry (0.5-1.0 Bq/m2 per day) and wet deposition (2.5 Bq/m2 per day)?
Significant health effects were found across Europe following Chernobyl so let's hope we don't get close. The possibility of even approaching those levels is something that the team running this seems to rule out, just as others in the government and the nuclear field are stating that the radiation isn't at levels of concern.
It seems that the most accurate statement based on what we know now is that increased exposure to radionuclides, even at low doses, increases the possbility of cancer in the population ("excess risk rate") but that very few additional cancers are expected to be caused by the fallout here (I still have yet to see a statement on expected increase in cancer rate per 100,000 posted here). The longer the situation continues, the more cancers will be caused in absolute terms but the overall incidence rate in the general population would not be able to be measured.
I think the underlying problem/tension here is that "levels of concern" in the view of policymakers or scientists is really a cost/benefit analysis like everything else--at what point does the cost of taking preventative measures and alarm outweight the increase in cancer cases? Leaders probably tolerate an increased cancer risk more than the average person would like but don't have great options given the massive cost that avoiding the exposures at these levels would take.
So in the meantime we have to hope that the situation with the reactors can be resolved sooner rather than later (doesn't look good) and that folks like the people here give the word if/when levels really do get worrisome for the man on the street. I've been pushing hard for data and studies on the effects of low levels of radiation and the real problem right now (especially for sensitive members of the population) is that there doesn't seem to be good information on dose levels <5 mSv.
WH
Dr. Jakobs' site is
Dr. Jakobs' site is here:
http://db.eurad.uni-koeln.de/prognose/radio.html
Could you do a comparison about the Iodine too?
I am wondering whether you could do a contamination comparison between the Bay area and Southern Germany with I131?
thank you.
If, and this is a big if,
If, and this is a big if, criticality is still occurring at Fukushima, I131 would stay at current levels and not decrease. All I131 would be flushed out every 60 days unless new material comes in to keep levels high.
If criticality stopped already, then in two months time there will be no more I131 left.
According to this report
According to this report from bloomberg, criticality is ongoing at Fukushima:
bloomberg.com/news/2011-03-30/record-high-levels-of-radiation-found-in-sea-near-crippled-nuclear-reactor.html
"Radioactive chlorine found March 25 in the Unit 1 turbine
building suggests chain reactions continued after the reactor
shut down, physicist Ferenc Dalnoki-Veress of the James Martin
Center for Nonproliferation Studies in Monterey, California,
wrote in a March 28 paper. Radioactive chlorine has a half-life
of 37 minutes, according to the report."
Your answer is a relief
Hello, I am from Germany and have major anxiety right now about this whole thing. Are you sure that this is what it would be, meaning we have less contamination than Southern Germany? Did you take into consideration a possible factor 10 correction factor for the not 100 percent sensitivity of Dr. chivers method?
thank you.