Fukushima: Texas A&M forecasts for April 5th

The Texas A&M Forecasts are in and they are aiming westerly:

Tuesday, April 5

1. • 2011-04-05 12Z - forecast only
2. • 2011-04-05 06Z - forecast only
3. • 2011-04-05 00Z - forecast only

Fukushima: Texas A&M forecasts, other simulations.

The Texas A&M forecasts are in:

Monday, April 4
• 2011-04-04 12Z - forecast only
• 2011-04-04 06Z - forecast only
• 2011-04-04 00Z - forecast only

I also found some readings from KEK in Tokyo, that are similar but more frequently updated than the SPEED! measurements. They are here and here. As shown earlier, these measurements show several spikes stemming from the releases from the reactors and a larger set of bump starting around March 21st that seem to correlate with the pool cooling events. As soon as the pools are filled, i.e. cooled, the sources terms stops immediately.

At the start of the accidents, there was not much data with regards to the source term at Fukushima, i.e how much elements were escaping from the reactors. Most of the computations performed by different groups were focused on  a worst case scenario of continuous release, which was never supported by any of the SPEED! measurements. The simulations include:

• Special Forecast products for Fukushima produced by NILU-ATMOS (disclaimer: These products are highly uncertain based on limited information for the source terms. Please use with caution and understand that the values are likely to change once we obtain more information on the overall nature of the accident. The products should be considered informational and only indicate 'worst case scenario' releases. From what we've learned recently, it seems releases of this magnitude have not yet occurred. Furthermore, these modeling products are based on global meteorological data, which are too coarse to provide reliable details of the transport of the plume across Japan.)
• Eurad simulations. (Fukushima site) Disclaimer: This simulation is a so called "worst case scenario" with continuous release rate. The value of 0001 Bq / m 3 correspond to appr. one millionth of the concentration at the source. At distances more than appr. 2000 km away from the source, the concentrations are not harmful to health. The simulation starts at fictitious 15.03. 00 UTC and will continue to run in order to Demonstrate the InterContinental. Relaese exact transport When rates are published we will restart the simulation with reliable values.

When given more data from the CTBTO, the german Eurad model was re-run and the dispersion model was compared as to when CTBTO stations would detect the plume from the Fukushima plant. The animated gif is here.

and seems to show a pretty good fit with regards to when the stations would detect elements given the new simulations. Finally, an NOAA HYSPLIT model is currently being run by somebody which seems to give similar result with regards to particle trajectories. It is here. 

Fukushima: Combining information from UC Berkeley, Texas A&M and TEPCO.

There is a new report from UC Berkeley that provides a timeline of the radiation measurements. The report is here:

Of interest today is the peak observed on March 24th (California time = GMT - 9). If one checks the Texas A&M maps, it looks like there is a possibility to connect this peak to a source term around March 20th at around midnight (GMT) or a little bit before.

The TEPCO press release for that time frame show something new that day among other things:

Cooling of spent fuel pools At approximately 8:21 am, March 20th, water discharge to Unit 4 by fire engine has started with the cooperation of Self-Defense Forces.

Or because the graph shows counting performed for the whole day in California (as opposed to actual time period) another later event:

Cooling of Spent Fuel  From 3: 05 PM to 5: 20 PM on March 20th, 40 tons of seawater was injected into Unit 2 by TEPCO employees.

The finding seems consistent with any of two source terms occurring at 

• 8:31 AM on March 20th, or about midnight March 20th (GMT) and,
•  3:05PM/5:20PM on March 20th or about (6:00AM GMT March 20th).

 The detection in California has occurred around March 24th (PST) or about March 24th/March 25th (GMT).

Hence it becomes difficult to delineate which of the two source terms was effectively detected at Berkeley. Now let us watch the Tokyo measurements. it shows a start at about 8:00 am March 21st (JST)

which seems consistent with reactor #4 pool cooldown. The second peak seems connected to the reactor #2 cooldown but it could also be connected to the smoke observed on top of unit 3 (March 21), however that would seem unlikely since according to TEPCO environmental readings remained at the same level when the fumes occurred. Once the cooldown is obtained and stable, there is no expectation of further release to the environment. The expectation is now that the radiation measurements should continue decreasing (irrespective of whether the winds are westerly).

Fukushima: Texas A&M Forecasts for April 1, A note on the Ibakari Analysis of March21st.

The Texas A&M forecasts are in:

Friday, April 1
• 2011-04-01 12Z - forecast only
• 2011-04-01 06Z - forecast only
• 2011-04-01 00Z - forecast only
Dates and times are shown in international format:  YYYY-MM-DD HHZ.  The Z indicates that the hours are given in Coordinated Universal Time (UTC or Greenwich time).
Japan is 9 hours ahead of UTC.  (00Z is 9:00 a.m. in Japan.)

In the Ibakari Analysis for the March 21st sudden dose rate increase, David, a commenter, pointed out the following:

That spike has been attributed to "rain" in sources that I've seen, for example in Daniel Garcia's graph here: http://twitpic.com/4f0qfr

The graph no longer exists but it showed the dose rate increase with a mention of "rain" next to it. I responded with:

Thanks for the comment and info. Rain is just the final means by which the radioactive components eventually are deposited in some area ( on some sensors). What is important to understand is how this is transported. In this entry, I am trying to figure out what is the possible source term at the plant that could have triggered this increase in the dose rate. With the help of the Texas A&M computations showing the delayed transport between the plant and some other area, it looks plausible to have this event be the cooling of the spent fuel pool of reactor 2 being the culprit. The cooling must have produced evaporation that eventually fed into the plume. The Texas A&M computation seem to suggest that there is a good fit between the time this event happened and the time is was detected several hours later in Ibakari. If you have any other source of information, I would love to hear about them.

Thanks David. I can see also the point that dose rate increase only when it rains because somehow the radiation is diffused all around as opposed to following specific trajectories such as the ones the Texas A&M team is computing.. However, while rain occurred in that area on March 21st ( http://weatherspark.com/#!graphs;ws=33162 ), there has been other rain events since with no corresponding large dose rate increase.

As can be seen from the SPEED! and other prefecture measurements graph at http://fleep.com/earthquake/ .Here is the Ibakari graph:

In other words, the insertion of sea water in the spent fuel pool of reactor 4 on March 21st, seems consistent with the dose rate increase in Ibakari several hours later (please note that I am not saying it is the only reason, just that it seems consistent based on the incomplete data we have so far). In particular, the trajectory computations show the possibility of the particles born from the cooling of the fuel rods to be over Ibakari in the right time frame. The rain is probably a compounding element that enabled the 4 microSv/hr dose rate increase as detected by the prefecture measurements. 

Dr. Matthias Braun from Areva produced a presentation, available from Energy from Thorium, that provides a background to folks who do not know nuclear systems, All the information in that presentation stem from data gathered from different sources accessible over the internet. Of interest are the following two slides. The first one is a timeline that stops just before March 21st and the second shows how different the accident in the pool  at reactor #4 is with regards to radiological release from similar release from reactor 1 through 3. As stated in the presentation, we do not know if these releases have occurred already.Let us note that the presentation talks about pool #4 whereas the dose rate increase seems consistent with water thrown in pool #2.

.

Fukushima: Ibakari Analysis for March 21st.

I wanted to come back to an dose rate increase in Ibakari that occurred on March 21st at 10:00 am. From here:

According to the TEPCO press release on March 20th, the only event I could find is the cooling of the spent fuel of reactor 2:

Cooling of Spent FuelFrom 3: 05 PM to 5: 20 PM on March 20th, 40 tons of seawater was injected into Unit 2 by TEPCO employees.

The Texas A&M maps show the trajectories at about that tine (3PM JST)

On the 22th, at 21:00 JST on March 22, there is a drop, that coincides with a westerly wind. Then the dose rate goes up as the winds comes back to the Ibakari region. So it looks like from the information currently available, the cooling of the pool in reactor 2 and attendant vapor generation might be responsible for this increase in dose rate in Ibakari.

Fukushima: TAMU Forecast March 31st, Analysis for Ibakari

The Texas A&M prediction maps for tomorrow are in:

Thursday, March 31

1. • 2011-03-31 12Z - forecast only
2. • 2011-03-31 06Z - forecast only
3. • 2011-03-31 00Z - forecast only
   
   

Please note that 06Z means 6:00 GMT or (6:00 + 9:00) 15:00 JST.

Yesterday, the prediction showed some trajectories going in the direction of Ibakari. Yesterday's map of the  region showed:

 Today's readings show the following map:

At first, there is no obvious difference using the color coding of that map. The historical charts in the same region show the following trend:

or a tiny increase of less than 0.2 microSv/hr at Takahagi. The map from Texas A&M is the one dated March 29th at 18 GMT or March 30 03:00 JST:

Fukushima: Source Term Analysis in Seattle. Potential understanding of Unit 3 fumes.

[Update: The folks at the Unversity of Washington are now aware of this opportunity]

The arxiv blog just featured a paper that appeared on arxiv that points to an analysis of the plume that landed at the University of Washington in Seattle. The paper is at the end of this entry. A good summary is here, from the text:

Finally, there are a huge number of possible breakdown products from nuclear fission in a reactor and yet the Seattle team found evidence of only three fission product elements--iodine, cesium and tellurium. "This points to a specifific process of release into the atmosphere," they say.

Cesium Iodide is highly soluble in water. So these guys speculate that what they're seeing is the result of contaminated steam being released into the atmosphere. "Chernobyl debris, conversely, showed a much broader spectrum of elements, reflecting the direct dispersal of active fuel elements," they say.

If one checks the Texas A&M predictions, arrival in Seattle on March 17-18 can be assumed thanks to this map that assumes ejection around 12 GMT on March 13th (or 21 JST March 13th)

This would correspond to an event in Unit 3 according to this map.

The folks at University of Washington ought to be looking at the Texas A&M simulations to see if and when they are going to catch up elements of the plumes.

Unit 3 is still a concern today as an analysis of the water outside of the secondary containment has shown elements such as Technetium-99m (Thanks David).

To see if the plume contains some of these elements, we ought to be looking at the smoke that left unit 3. As per TEPCO's report:

At approximately 4:00 pm, March 21st, light gray smoke was confirmed arising from the floor roof of the Unit 3 building. On March 22nd, the color of smoke changed to somewhat white and it is slowly dissipating.

-At approximately 10:45 pm on March 22nd, the light in the main control room was turned on.

-At around 4:20 pm on March 23rd, our staff confirmed light black smoke belching from the Unit 3 building. At approximately 11:30 pm on March 23rd and 4:50 am on March 24th, our employee found no signs of smoke.

If one converts these dates from JST to GMT, we have:

7:00 am GMT March 21st: light gray smoke
7:20 am March 23rd: light black smoke

A simulation for the March 21st event was performed for 6:00 am and it shows that plume hitting Seattle tomorrow.

A simulation for the second event does not seem as conclusive.



The paper: Arrival time and magnitude of airborne fission products from the Fukushima, Japan, reactor incident as measured in Seattle, WA, USA by J. Diaz Leon, J. Kaspar, A. Knecht, M. L. Miller, R. G. H. Robertson, A. G. Schubert. The abstract reads:

We report results of air monitoring started due to the recent natural catastrophe on March 11, 2011 in Japan and the severe ensuing damage to the Fukushima nuclear reactor complex. On March 17-18, 2011 we detected the first arrival of the airborne fission products 131-I, 132-I, 132-Te, 134-Cs, and 137-Cs in Seattle, WA, USA, by identifying their characteristic gamma rays using a germanium detector. The highest detected activity to date is less than 32 mBq/m^3 of 131-I.

Fukushima: Timelines, the Fog of Data, Comparing the DOE data and Texas A&M's simulations, Forecasts

The Neutroneconomy blog has an update on Dose Readings in Japan.and provides some analysis of the plumes and their detection. Also via the Neutroneconomy blog, R.C Hoetzlein provides a very nice timeline.

There is another one on the NYT.

Having a good timeline should allow us to make a better comparison with the Texas A&M simulations and readings on the ground. To the untrained eye it looks like there is only one set of sensors. However, the fog of data is fed from are several sensor networks. There are:

• The MEXT ( SPEED! network ) via Marian Steinbach's effort on the Japan Radiation OpenData
• Geiger Crowd network (contribute data and software here)
• Local prefecture networks as featured in this site.( Radiation Levels for Tokyo, Chiba, Saitama, Ibaraki, Tochigi, Gunma, Yamagata, Miyagi, Iwate )
• RDTN.ORG, uses SPPED! data and other networks
• Radiation Crowd Map.
• TEPCO readings (Thanks NeutronEconomy) only in Japanese it seems.
• Citizen centered networks linked to the internet through entities like Pachube (Pachube also get information from the SPEED! network thanks to Marian Steinbach's effort). This last network has issue on its own when it comes to getting peoples's sensors to the network. It includes the need for getting digital information from analog Geiger counters.

Beside the atmospheric ground measurements, there are also tap water measurements (see graphs).

We have updated a google maps featuring the MEXT data and some other data we  mentioned in the blog before:






View Fukushima Plume (Sensors and Measurements) in a larger map


The Radiation data from the SPEED! network can also be found on this map.

With regards to the source term, the Fukushima Dai-ichi plant, Cheryl Rofer  has a take on the white smoke coming out of the plant:

The puffs of smoke that have caused temporary evacuations of the control rooms have not been accompanied by increases in radiation. A gray or black color could indicate a fire, while white “smoke” is more likely steam.

From the FEPC reports, the spent fuel pools at Units 2, 5, and 6 are at acceptable temperatures. Water is being added to the pools at Units 3 and 4, but no temperature is given. The reactor cores in Units 1, 2, and 3 remain partially uncovered by water, but the fact that their containment is holding pressure suggests that there are no large breaches. 

Marian Steinbach has started putting the readings she obtained from the SPEED! network into a small video. This is outstanding. If we could include all the data from all the sensor networks and have a similar video from the plumes, I am sure we could begin to infer something

Here is the SPEEDI Radiation Data Animation - Draft (Mar 20, 00:00 to Mar 23, 15:20 UTC)

As I was looking at the trajectory computations by the fine folks at Texas A&M and the aerial assessment provided by DOE yesterday, I am in need of an explanation: Namely, if you look at the DOE measurements, there is red corridor going up on the left of Fukushima Dai-ichi:

yet when one check the Texas A&M simulations, only a period of potentially six hours provided this region to the exposure to the plume.namely:

The three days worth of simulation by Texas A&M and covered by the DOE survey are:

Saturday, March 19
• 2011-03-19 18Z - analysis + forecast
• 2011-03-19 12Z - analysis + forecast
• 2011-03-19 06Z - analysis + forecast
• 2011-03-19 00Z - analysis + forecast
Friday, March 18
• 2011-03-18 18Z - analysis + forecast
• 2011-03-18 12Z - analysis + forecast
• 2011-03-18 06Z - analysis + forecast
• 2011-03-18 00Z - analysis only
Thursday, March 17
• 2011-03-17 18Z - analysis only
• 2011-03-17 12Z - analysis only
• 2011-03-17 06Z - analysis only
• 2011-03-17 00Z - analysis only

Finally, here are the new Texas A&M forecast for today and tomorrow (times are in GMT).

Friday, March 25
• 2011-03-25 12Z - forecast only
• 2011-03-25 06Z - forecast only
• 2011-03-25 00Z - forecast only
Thursday, March 24
• 2011-03-24 18Z - forecast only
• 2011-03-24 12Z - forecast only
• 2011-03-24 06Z - forecast only
• 2011-03-24 00Z - forecast only

Fukushima: U.S. Department of Energy Aerial and Ground Monitoring Data

The U.S Department of Energy just issued a press release and a presentation that featured aerial and ground measurement data. In the presentation there is also a mention of a ground US monitoring station deployed by their Consequence Management Response Teams near Fukushima. (Download the presentation here)

Fukushima: Levels of radioactive iodine and cesium in tap water

The Japanese Ministry of Education, Culture, Sport, Science and Technology (MEXT), which has published charts we already referenced here (they are now available from our map) of the levels of radiation measured in all prefectures, also published charts of the levels of radioactive iodine 131 and cesium 137 measured in tap water.

Those charts are gathered on this page (link to the source is available).

Fukushima: Texas A&M simulation vs ground measurements

One of the "raison d'etre" of this blog is to compare ground measurements from government or citizen sensor networks and the diverse computational simulations used to model man made or natural plumes. While the French ISRN has performed some computations, its own sensor network is likely to not going to be able to pick up the radiation as it is likely to be in the background when it reaches metropolitan France. At Texas A&M,   Kenneth Bowman, Cameron  Homeyer have continued providing computation of the transport of aerosols from the Fukushima plant. How do these computations compare with the readings from the different government owned sensor networks ?. In particular, how do these measurements compare with the two events listed in the Texas A&M maps.?

The fire at Reactor 4 took place at 9:40 am March 15 JST (0:40 March 15 GMT) while the explosion of reactor 2 took place earlier at 6:10 a.m (21:10 March 14 GMT) that day (see here for references)

Tuesday, March 152011-03-15 00Z - analysis only (time of reported fire in reactor #4)

According to the trajectories, four ticks later (12 hours later) it is over Ibakari prefecture. The first peak is at 6 AM JST on March 16th (21:00 GMT March 15th). While the red tracks goes south, the green and blue stays over that prefecture and are a therefore consistent with the peak recorded there at 6AM JST (21 hours later). But that measurement is also consistent with the explosion at reactor #2.(24 hours later) as can be seen in the following map.

Monday, March 14 • 2011-03-14 21Z - analysis only (time of reported explosion in reactor #2)

So from a first reading of these maps, it does not look feasible to evaluate which of these two accidents is contributing to the measurements on the ground. Let us also not that the days after may 16, 17, the aerosols went over the pacific ocean.thereby reducing the dose to the land.

Fukushima: A radiation dose chart

Randal Munroe, famous for being the author or XKCD, has published with the help of some other people a chart giving a glimpse of the meaning of radiation levels. As he states himself, this chart is not meant to be a scientific reference, but it still proves very helpful in putting in perspective a given radiation level.

Sources used are credited on the page.

http://xkcd.com/radiation/

Fukushima: French ISRN and Texas A&M Simulation of Fukushima plume from March 12 to March 22: Tokyo and Global scale

Today, the French ISRN released some results of its computation of the Fukushima plume over Tokyo. Another simulation shows the plume till March 25th for the whole Globe taking into consideration data from the French meteorological office. 

2 - The dispersion of radioactive releases into the atmosphere
IRSN simulated atmospheric dispersion of releases estimated between 12 and 22 March, using its numerical model applicable to long distance (scale of several hundred kilometers), using observations and weather forecasts provided by Weather France.
This simulation was applied to the cesium 137, as a tracer of the plume during this period. The modeling results are expressed in becquerels of cesium-137 per cubic meter of air (Bq / m 3).
Watch the simulation of the plume
This modeling performed throughout Japan shows that the plume has led in directions that have varied over time: first north-east until March 14, then south and southeast west toward Tokyo, March 15, then east toward the Pacific Ocean.
IRSN compared the simulation results with the results of measurements of air contamination carried in Tokyo. They are the same order of magnitude as the values ​​measured in this city, as shown in the charts below for iodine 131 and cesium 137.
This comparison allows us to consider that the air dispersion modeling performed by IRSN to produce satisfactory results for the agglomeration of Tokyo and the doses calculated by IRSN from this modeling are representative of the doses may have been received by the population exposed to the radioactive plume.

and then for the whole globe:

4 - Modeling the dispersion of radioactive releases into the atmosphere on a global scale
From the estimated releases from IRSN, Meteo France has simulated the dispersion of radioactive releases from great distances, projected until March 26.


Watch the simulation

According to this simulation, the plume would now reached the north-eastern Siberia, the United States and western Atlantic. It should reach France from 23 or 24 March.
Merger expected to run from this model could be of the order of 0,001 Bq / m 3 in France and the overseas departments of the northern hemisphere. As expected, the southern hemisphere is not significantly affected by this large-scale dispersal.
For comparison, values ​​measured in the days following the Chernobyl accident had exceeded 100 000 Bq / m 3 in the first few kilometers around the plant and they were in the range of 100 to 1000 Bq / m 3 in the country most affected by the plume (Ukraine, Belarus); France, values ​​measured in the east were the order of 1 to 10 Bq/m3 (May 1, 1986). Today, a very low activity of cesium-137 remains in the air, on the order of 0.000001 Bq/m3.

To give some perspective, as per wikipedia, one Bq is defined as the activity of a quantity of radioactive material in which one nucleus decays per second.. From the TORCH report on how to computer the dose due to Cesium from its Bequerel units::

To sum these properties up

• The dose rate due to external irradiation from uniform contamination of the ground by ¹³⁷Cs is 1.6 x 10^-12 Sv hr^-1 Bq^-1 m².

• The internal dose for ingestion is 1.2 x 10^-8 Sv Bq^-1

• The internal dose for inhalation is 8.7 x 10^-9 Sv Bq^-1

The maximum for this global computation is 1000 Bq/m^3. All other colors are decreasing by increment of ten from that maximum. This number has then to be multiplied by the low numbers above to obtain a dose. As can be seen from the US EPA detectors, this dose is part of the background radiation level. Another map of interest shows that the plume modeling is different for different  research teams. The folks at Texas A&M provide computations showing particles in the plume flying at 2 to 4 km altitude while the french model is restricted to 500m high.