Accumulated fallout projections to date
Thank you all, very much for your assistance in monitoring the situation in Japan and CalifornIa.
Can you please comment on the accuracy of the fallout maps created by Dr. Hermann Jakobs in Germany. His forcast is located here:
http://db.eurad.uni-koeln.de/prognose/radio.html
Of particular concern is the wet deposition map. It is showing forcasts of 2-5000 Bq/m2 for Cesium contamination centered over the California coast:
http://db.eurad.uni-koeln.de/prognose/data/alert/wdcs_hem_1h_72_1.gif
If true, that would be twice the average cumulative deposition in Europe from Chernobyl according to this map:
http://maps.grida.no/library/files/storage/chernobyl_001.png
This certainly is a worrisome prospect for us in California, if true.
what is the actual geographic size of California versus Europe?
does anyone know the size of California related to the countries in Europe so we can get an idea of the concentration of contamination?
thanks
California = 163,696 sq
California = 163,696 sq mi
Britain = 94,060 sq mi
France = 260,558 sq mi
Germany = 137,847 sq mi
I am confused about the
I am confused about the numbers in this thread. Can somebody here please sum up the conclusion as to the agreement or disagreement between Jakobs forecasts and actual measurements by the NUC? In particular, how do we in CA fare in comparison to Europe after Chernobyl?
Dr. Jakobs' original
Dr. Jakobs' original estimation agreed favorably with local readings before he updated his model. Now it looks like the atmospheric levels are 10x more than he is forecasting. NUC values being hard data as opposed to a model are more likely to be closer to actual values, unless there is gross error.
I think we still need more data about soil and food contamination levels to get a better picture of how this is shaping up.
By "atmospheric" you mean
By "atmospheric" you mean the data taken by the EPA?
If I understand you correctly his original forecasts for rain agreed well with NUC, however now EPA is measuring higher Air particulates than his original forecasts. so one would expect higher concentration in rain as well. In other words, are you saying that the EPA and NUC disagree? I still can't follow...
Anyway, you're also writing his current estimate based on actual, not simulated, weather patterns gives 0.1-100 Bq/m2 for CA for Cesium. That's a huge spread. Where is it 0.1 and where is it 100?
Taking an average over the last weeks measurement of NUC of 0.5 Bq/l for Cesium activity, and 20 inches=50 cm of precipitation over the time span (I can't find the actual number on the web) I'm arriving at 10x10x5=500 liter (a liter fits in a 0.1x0.1x0.1 meter box) and therefore 2,500 Bq/m2 for Berkeley, which is insanely frightening since it is the same as most of Europe got after Chernobyl and the long term impact on crops we've seen there was very bad. Please tell me that I made a mistake in my calculation.
The average you state, at
The average you state, at 0.5 Bq/l is probably 2.5x higher than the actual average based on the NUC numbers to date. It more like around avg. 0.2 Bq/l.
We need a sampling of the
We need a sampling of the area around UCB.
Some of the water runs off, some gets absorbed. Your calculations would be a theoretical maximum.
theoretical maximum
I understand that my calculation would be a theoretical maximum, but I believe what Jakobs means by deposition is what ever falls out of the sky. His maps show depositions two orders of magnitude (!!) lower than what one would infer based on the NUC data, i.e. they show 10-100 Bq/m2.
The only way these numbers are compatible is if Jakobs means by deposition "whatever stays in the soil" and NUC means "whatever falls from the sky". However that would entail that 99% of the Cesium would have gone into the runoff and only 1% into the soil, which is vastly inconsistent with NUC's runoff measurements (i.e. they measured a runoff concentration of a few percent).
Assuming Jakobs means "deposition before runoff" they are two orders of magnitude discrepan, so we can conclude that either Jakobs vastly underestimated the deposition or NUC has a huge measurement error. I bet the former is the case and the actual deposition is 1000-10,000 Bq/m2.
The numbers you state are
The numbers you state are highly unlikely. The IAEA has stated the highest ground readings measured around Fukushima prefecture in the evacuation zone is on the order of 70 Bq/m2.
You're right, my calculation
You're right, my calculation gives 250 Bq/m2, not 2,500. However that's still quite high soil deposition (and a substantial runoff has been ruled out by NUC). Can you point me to the source for the fallout around Fukushima? The wind blew east, but I don't believe that it's that much less than here (and we KNOW it is somewhere in the 25-250 Bq/m2 here from the NUC measurements).
The real NUC average us
The real NUC average us closer to 0.2 Bq/l. At that level your calculations would fall at the high end if Dr. Jakobs scale fir his current prediction at 100 Bq/m2.
http://www.iaea.org/newscente
http://www.iaea.org/newscenter/news/tsunamiupdate01.html
Scroll down to the update at 14:30 UTC, subheading 2.
Are you referring to
Are you referring to this?
"On 27 March, deposition of iodine-131 was detected in 9 prefectures, and deposition of cesium-137 in 4 prefectures. The highest values were observed in the prefecture of Tochigi with 320 becquerel per square metre for iodine-131 and 73 becquerel per square metre for caesium-137. In the other prefectures where deposition of iodine-131 was reported, on 27 March, the range was from 6.4 to 110 becquerel per square metre. For caesium-137, the range was from 16 to 61 becquerel per square metre. In the Shinjyuku district of Tokyo, the daily deposition of iodine-131 on 27 March was 100 becquerel per square metre, while for caesium-137 it was 36 becquerel per square metre. No significant changes were reported in the 45 prefectures in gamma dose rates compared to yesterday. "
That presentation seems more consistent with *daily* deposition reporting than total. Some additional thoughts...
http://allthingsnuclear.org/post/4143610830/iaea-data-appear-to-show-increased-ground
Dr. Jakobs has updated his
Dr. Jakobs has updated his forecast model with the following statement:
First measurements are now available from the CTBTO. The observed I-131 activity concentrations are in the order of 0.001 to 0.1 Bq/m3 (See graphics right, with permission of the Federal Office for Radiation Protection, Germany)
Based on these observations a new estimation of the emission rate was done and the transport calculations were updated. A first comparison indicates identical arrival times of the radioactive cloud at the CTBTO stations. A detailled verifikation of the calculations will follow.
Deposition: The dry and wet deposition display the total accumulated deposition along the path of the plume.
He has direct measurements in Germany of the I-131 levels with which to reconstruct the original output st Fukushima.
Based on these numbers he has predicted total fallout on the 0.1 to 100 Bq/m2 range for California Cesium fallout.
Dr. Jakobs assumed, as an
Dr. Jakobs assumed, as an initial value for output, 10^15 Bq/day. This value was 10% of Chernobyl and a good starrting point for Cesium fallout.
To date, media reporting has said that Fukushima has been emitting 20-30% of the Chernobyl accident, for Cesium. Dr. Jakobs' calculations are probably lower than measured values at this point.
Cumulative amounts
What worries me is the cumulative effect. This has been what? 13 days now we have been exposed to these toxic substances. Is this being taken in to consideration?
I am starting to feel like this is going very bad very fast for California and other western states.
Site in Austria where they have been doing a lot of number crunching you may find of interest. Must be translated.
http://www.zamg.ac.at/aktuell/index.php?seite=1&artikel=ZAMG_2011-03-17G...
I would rather spend time
I would rather spend time testing produce than discussing models. What does it cost to assay lettuce for caesium-137? Who knows how to do it?
--bks
testing produce
I have been wondering about this. Glad to help fund/execute testing if anyone knows how to initiate.
Agreed. The EPA has been mum
Agreed. The EPA has been mum on updates to water and milk concentrations.
It would seem prudent to start independent measurements of milk and produce at this point.
I would think the FDA would
I would think the FDA would be testing them
It would be helpful to know
It would be helpful to know what the units are on the x-axis. Is it Bq/m^3 (sort of implied in the text)? "The value of 0.1 Bq/m3 correspond to appr. one millionth of the concentration at the source." That would then imply that the orange areas are approx. 35/1000000 X the concentration "at the source" (which is not given)? That would be significantly higher than the highest measured at UCB. But then the orange cloud shown from two days ago (ground level) was only over the southwest (where we are).
Just to correct, clearly I
Just to correct, clearly I have no basis for comparing an unknown absolute value, dependent on unknown source value, to the UCB readings.
The page states that the
The page states that the initial assumption out output from Fukushima of Cesium is 10^15 Bq/day.
The X-axis for the atmoshperic transport graphs are Bq/m3 and for the fallout graphs are Bq/m2.
OK, well now I'm more
OK, well now I'm more confused. So the yellow, for example, means 1 to 2 Bq/m^3? That can't be right, so, what, divide it by 10^6? That would get numbers that are in the ballpark with the measurements reported on this site, but not sure what the rationale is. Where does the 10^15 Bq/day come in?
His current ground level
His current ground level forcast has the value at 0.5 to 1.5 bq/m2 on the coast of California.
The readings from the air filtration are in Bq/l and there are 1000 liters to a cubic meter of air.
The latest reading was 2.2e-7 Bq/l which works out to about 2.0 Bq/m3. So if anything he's low.
He is also predicting at 2500 and 5000m altitudes. This calculation was for ground level.
I'm a bit confused. If he's
I'm a bit confused. If he's getting 0.5-1.5 Bq/m2 on the coast of CA, that is significantly less than over e.g. Germany after Chernobyl, about 10,000 times less. Is this what you're saying he's getting now? That would mean his initial simulation predicted 1,000 times more than what he is now getting. Can you confirm this?
Also, if he's getting 0.5-1.5 Bq/m2 (let's just call it 1 Bq/m2) and we know that NUC measured 0.5 Beq/l that would agree with Jakob's calculation if there were 1l of fallout per square meter. However it seems there should have been significantly more rainfall, probably about 10 inches over the last week, in which case we'd be looking at 250 liters per square meter and 250 Bequerel per square meter.
The 0.5 to 1.5 value is what
The 0.5 to 1.5 value is what is in the air. The fallout, or what has accumulated on the ground is 2-5000 times that amount according to Dr. Jakobs.
2.2e-7 Bq/l * 1e3 l/m3 =
2.2e-7 Bq/l * 1e3 l/m3 = 2.2e-4 Bq/m3
is that not right?
e is Euler's number, not
e is Euler's number, not shorthand for exponential.
e^1 ~ 2.718
The results are written with
The results are written with an upper-case E and therefore are powers of ten.
That should be 0.5 to 1.5
That should be 0.5 to 1.5 Bq/m3.
Two more points: 1) I
Two more points:
1) I wonder what Dr. Jakob's forecasts were based on. The amount of rainfall on the CA coast over the last two weeks was extremely high, and it seems unlikely that the forecast anticipated this. In other words, the amount of fallout could be much higher.
2) Assuming an average deposition of 10 Bq/l, conservatively based on the NUC's measurements over the past week, we'd need a thousand liters of rainfall per square meter to yield the same level of contamination as e.g. southern Germany. That's 25 inches of rainfall. Did we get that much?
One question I had was whether the map at http://maps.grida.no/library/files/storage/chernobyl_001.png is based on Cesium, Iodine, or a combination of all isotopes. If the latter, one would have to provide a mean half-time of the various isotopes to compare to the situation here. Note that the 10 Bq/l number above is based mostly on Iodine, which decays very rapidly and is therefore of far less long-term concern than e.g. Cesium.
How difficult is it to get a
How difficult is it to get a baseline reading from 1 m2 of a random set of patches of ground around the UC campus?
That would actually be
That would actually be rather difficult. Our current measurements are only possible because can take a substance, e.g. rainwater, and place it in a very specific geometry around our radiation detector. You can't really do that with soil, concrete, vegetation, etc. in a square meter of ground. We could theoretically try to move a detector outside, but then you are getting radiation from a large area of ground, with an efficiency that would require advanced modeling to understand, plus any buildings in sight are contributing radiation, plus the air around the detector . . it would be difficult to actually calibrate it to Bq/m^2.
How is it being measured by
How is it being measured by the teams in Japan?
How difficult
Lets face it...our government is not being transparent on this matter. Why?
They aren't doing much of anything except placating us and not doing that very well either.
Seriously, what would they say now? Did they project what the consequences would be for us if the this went on for 2-3 weeks? Or a month? They didn't even know what amounts of radiation had been released and how long did it take us to get "experts" over there to find out what was really happening?
Dr. Chivers, did you measure
Dr. Chivers, did you measure the *amount* of rainfall per square foot during your various measurement intervals?
That way we could extrapolate to the map provided by the original poster.
Would that mean that
Would that mean that agriculture in California is now contaminated beyond hope?
It's somewhat relative. Some
It's somewhat relative. Some people don't mind eating contaminated plants as long as the statistical risk of getting cancer from doing so is reasonably low. Also there are certain crops that are less sensitive because they take up less radioactive isotopes.
Fact is the Cesium that has contaminated most of CA over the last week or two will be there for a very long time, i.e. when my grand-children are born half of it will still be there, when my great-great-great-grandchildren are born 10% of it will still be around.
It's just not a place where I won't feel comfortable living anymore, but I respect if other people have different opinions and plan their lives accordingly.
Meant to write "It's just
Meant to write "It's just not a place were I feel comfortable living anymore".
My family and I have already
My family and I have already started to think about alternative places to move to in the world, probably the southern hemisphere. We came to and stayed in CA mostly for its natural beauty and access to fresh and healthy food, and if anything is clear that the healthy food part is now a thing of the past. I also don't want to have to be concerned each time my children play in nature.
I'm not surprised as the
I'm not surprised as the total emission was comparable to Chernobyl already last week and it's all been falling out over CA, so one would naively expect that the amount of radioactive material will have the same order of magnitude as Chernobyl. And that's just up to this point...
Chernobyl fall out
Does anyone know how many days the Chernobyl fall out lasted? I mean, how many days the reactor was emitting the radioactivity? Was it just one day explosion or did the fall out go on for several days? This would be important for us in CA as to a comparison with this situation. I agree with the other postints, that it could go higher if this meltdownn will go on for another month or two.
Does anyone know whether Oranges and citrus will be affected?
CHERNOBYL FALLOUT DATA:
CHERNOBYL FALLOUT DATA: ANNOTATED BIBLIOGRAPHY
RADNET
Information about source points of anthropogenic radioactivity
A Freedom of Nuclear Information Resource
http://www.davistownmuseum.org/cbm/Rad7.html
The IAEA is saying that the
The IAEA is saying that the plant will need some time to stabilize. They have not said how much time. Reading between the lines, I'm thinking months.
http://english.kyodonews.jp/news/2011/03/81615.html