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A. Stohl1, P. Seibert2, G. Wotawa3, D. Arnold2,4, J. F. Burkhart1, S. Eckhardt1, C. Tapia5, A. Vargas4, and T. J. Yasunari61NILU – Norwegian Institute for Air Research, Kjeller, Norway2Institute of Meteorology, University of Natural Resources and Life Sciences, Vienna, Austria3Central Institute for Meteorology and Geodynamics, Vienna, Austria4Institute of Energy Technologies (INTE), Technical University of Catalonia (UPC), Barcelona, Spain5Department of Physics and Nucelar Engineering (FEN),Technical University of Catalonia (UPC), Barcelona, Spain6Universities Space Research Association, Goddard Earth Sciences and Technology and Research, Columbia, MD 21044, USAAbstract. On 11 March 2011, an earthquake occurred about 130 km off the Pacific coast of Japan's main island Honshu, followed by a large tsunami. The resulting loss of electric power at the Fukushima Dai-ichi nuclear power plant (FD-NPP) developed into a disaster causing massive release of radioactivity into the atmosphere. In this study, we determine the emissions of two isotopes, the noble gas xenon-133 (133Xe) and the aerosol-bound caesium-137 (137Cs), which have very different release characteristics as well as behavior in the atmosphere. To determine radionuclide emissions as a function of height and time until 20 April, we made a first guess of release rates based on fuel inventories and documented accident events at the site.

This first guess was subsequently improved by inverse modeling, which combined the first guess with the results of an atmospheric transport model, FLEXPART, and measurement data from several dozen stations in Japan, North America and other regions. We used both atmospheric activity concentration measurements as well as, for 137Cs, measurements of bulk deposition. Regarding 133Xe, we find a total release of 16.7 (uncertainty range 13.4–20.0) EBq, which is the largest radioactive noble gas release in history not associated with nuclear bomb testing. There is strong evidence that the first strong 133Xe release started very early, possibly immediately after the earthquake and the emergency shutdown on 11 March at 06:00 UTC. The entire noble gas inventory of reactor units 1–3 was set free into the atmosphere between 11 and 15 March 2011. For 137Cs, the inversion results give a total emission of 35.8 (23.3–50.1) PBq, or about 42% of the estimated Chernobyl emission. Our results indicate that 137Cs emissions peaked on 14–15 March but were generally high from 12 until 19 March, when they suddenly dropped by orders of magnitude exactly when spraying of water on the spent-fuel pool of unit 4 started. This indicates that emissions were not only coming from the damaged reactor cores, but also from the spent-fuel pool of unit 4 and confirms that the spraying was an effective countermeasure. We also explore the main dispersion and deposition patterns of the radioactive cloud, both regionally for Japan as well as for the entire Northern Hemisphere. While at first sight it seemed fortunate that westerly winds prevailed most of the time during the accident, a different picture emerges from our detailed analysis

Exactly during and following the period of the strongest 137Cs emissions on 14 and 15 March as well as after another period with strong emissions on 19 March, the radioactive plume was advected over Eastern Honshu Island, where precipitation deposited a large fraction of 137Cs on land surfaces. The plume was also dispersed quickly over the entire Northern Hemisphere, first reaching North America on 15 March and Europe on 22 March. In general, simulated and observed concentrations of 133Xe and 137Cs both at Japanese as well as at remote sites were in good quantitative agreement with each other. Altogether, we estimate that 6.4 TBq of 137Cs, or 19% of the total fallout until 20 April, were deposited over Japanese land areas, while most of the rest fell over the North Pacific Ocean. Only 0.7 TBq, or 2% of the total fallout were deposited on land areas other than Japan.Discussion Paper (PDF, 6457 KB)   Supplement (13 KB)   Interactive Discussion (Open, 0 Comments)   Manuscript under review for ACP   

The impacts on the ocean of releases of radionuclides from the Fukushima Dai-ichi nuclear power plants remain unclear. However, information has been made public regarding the concentrations of radioactive isotopes of iodine and cesium in ocean water near the discharge point. These data allow us to draw some basic conclusions about the relative levels of radionuclides released which can be compared to prior ocean studies and be used to address dose consequences as discussed by Garnier-Laplace et al. in this journal.(1) The data show peak ocean discharges in early April, one month after the earthquake and a factor of 1000 decrease in the month following. Interestingly, the concentrations through the end of July remain higher than expected implying continued releases from the reactors or other contaminated sources, such as groundwater or coastal sediments. By July, levels of 137Cs are still more than 10 000 times higher than levels measured in 2010 in the coastal waters off Japan. Although some radionuclides are significantly elevated, dose calculations suggest minimal impact on marine biota or humans due to direct exposure in surrounding ocean waters, though considerations for biological uptake and consumption of seafood are discussed and further study is warranted.

there was no large explosive release of core reactor material, so most of the isotopes reported to have spread thus far via atmospheric fallout are primarily the radioactive gases plus fission products such as cesium, which are volatilized at the high temperatures in the reactor core, or during explosions and fires. However, some nonvolatile activation products and fuel rod materials may have been released when the corrosive brines and acidic waters used to cool the reactors interacted with the ruptured fuel rods, carrying radioactive materials into the ground and ocean. The full magnitude of the release has not been well documented, nor is there data on many of the possible isotopes released, but we do have significant information on the concentration of several isotopes of Cs and I in the ocean near the release point which have been publically available since shortly after the accident started.

We present a comparison of selected data made publicly available from a Japanese company and agencies and compare these to prior published radionuclide concentrations in the oceans. The primary sources included TEPCO (Tokyo Electric Power Company), which reported data in regular press releases(3) and are compiled here (Supporting Information Table S1). These TEPCO data were obtained by initially sampling 500 mL surface ocean water from shore and direct counting on high-purity germanium gamma detectors for 15 min at laboratories at the Fukushima Dai-ni NPPs. They reported initially results for 131I (t1/2 = 8.02 days), 134Cs (t1/2 = 2.065 years) and 137Cs (t1/2 = 30.07 years). Data from MEXT (Ministry of Education, Culture, Sports, Science and Technology—Japan) were also released on a public Web site(4) and are based on similar direct counting methods. In general MEXT data were obtained by sampling 2000 mL seawater and direct counting on high-purity germanium gamma detectors for 1 h in a 2 L Marinelli beaker at laboratories in the Japan Atomic Energy Agency. The detection limit of 137Cs measurements are about 20 000 Bq m–3 for TEPCO data and 10 000 Bq m–3 for MEXT data, respectively. These measurements were conducted based on a guideline described by MEXT.(5) Both sources are considered reliable given the common activity ratios and prior studies and expertise evident by several Japanese groups involved in making these measurements. The purpose of these early monitoring activities was out of concern for immediate health effects, and thus were often reported relative to statutory limits adopted by Japanese authorities, and thus not in concentration units (reported as scaling factors above “normal”). Here we convert values from both sources to radionuclide activity units common to prior ocean studies of fallout in the ocean (Bq m–3) for ease of comparison to previously published data.

you would think the Japanese government would be doing everything in its power to contain the disaster. You would be wrong—dead wrong.

nstead of collecting, isolating, and guarding the millions of tons of radioactive rubble that resulted from the chain reaction of the 9.0 earthquake, the subsequent 45- to 50-foot wall of water that swamped the plant and disabled the cooling systems for the reactors, and the ensuing meltdowns, Japanese Environment Minister Goshi Hosono says that the entire country must share Fukushima’s plight by accepting debris from the disaster.

an estimated 20 million tons of wreckage on the land, much of which—now ten months after the start of the disaster—is festering in stinking piles throughout the stricken region. (Up to 20 million more tons of rubble from the disaster—estimated to cover an area approximately the size of California—is also circulating in the Pacific.)

A recent headline on the six crippled Fukushima Daiichi Nuclear Reactors read: “40 microSv/h detected from radioactive gravel site used for schools, homes — Measured one meter above source,” Jan 21, 2012. I asked Physicist Dr. Paolo Scampa, PhD. of the AIPRI Blog fame, what this translates to for everyday people, their kids and families. The Fukushima nuclear tragedy is still going on after 335 days as of Wed, Feb 08, 2012 affecting the entire world.

US Imperial Unit Measurements Dr. Scampa stated

“An absorbed dose of 40 microSievert/hour at one Meter or about 39 inches above the ground, means a radioactive deposit creating an average of 12,330,000.00 Cesium 137 nuclear explosions per second (Becquerels) for every 39 inches square over much of the Northern Hemisphere. Further, the radiation is spreading rapidly through the air. The Earth’s  surface is covered with many deadly radioactive isotopes from the six crippled Fukushima Daiichi Nuclear Reactors.”  “This is 22 times more Radiation than the IAEA (International Atomic Energy Agency) decreed for the Chernobyl Nuclear Reactor Disaster Exclusion Zone when they said everyone had to leave.

"The radiation from this unreported but very dangerous event was released without protecting the residents of Fukushima Prefecture -- especially the children. But the radiation was detected at elevated levels from 2:30 AM until 7:30 AM on a monitor in Ibaraki Prefecture. How many Curies were released? When will this nuclear war against the Japanese people and the Northern Hemisphere ever end? Instead of evacuation, the government gives the children (sick with radiation symptoms) film badges to measure the external exposure dose ... another study group like US govt. studies on Hiroshima and Nagasaki victims (they are still being studied), Iraq victims, Gaza victims. And the US government did the same thing to Americans during 1,300 nuclear bomb tests in the US."

And if that's not enough bad news, we have another big problem. Here at home we have two Nebraska nuclear power stations located near the Missouri River, and one is already submerged in flood waters. A hole torn in a 2,000-foot, inflatable barrier placed around the facility allowed over several feet of water to pour into containment buildings and electrical transformers at the plant. This disaster was reported -- and then quickly silenced -- by mainstream media. Cooper Nuclear Station, one of the nuclear power plants in the area, declared a "Notification of Unusual Event" after the U.S. Army Corps of Engineers released massive amounts water from two dams. This event is ongoing. ...

I wish I knew how all of this will play out. All I know is sometimes we all feel like we're just communities of puny little ants who can never change a thing. But don't despair, for we are many ... and when we combine our numbers, we are a very powerful force! I truly believe that we are the ones we have always waited for. As a lover of American Indian culture, I recall an old Indian wise man once said...

Sixteen tons and what you get is a nuclear catastrophe. The explosions that rocked the Fukushima No.1 nuclear plant were more powerful than the combustion of hydrogen gas, as claimed by the Tokyo Electric Power Company. The actual cause of the blasts, according to intelligence sources in Washington, was nuclear fission of. warhead cores illegally taken from America's sole nuclear-weapons assembly facility. Evaporation in the cooling pools used for spent fuel rods led to the detonation of stored weapons-grade plutonium and uranium.   The facts about clandestine American and Israeli support for Japan's nuclear armament are being suppressed in the biggest official cover-up in recent history. The timeline of events indicates the theft from America's strategic arsenal was authorized at the highest level under a three-way deal between the Bush-Cheney team, Prime Minister Shinzo Abe and Elhud Olmert's government in Tel Aviv.

Tokyo's Strangelove   In early 2007, Vice President Dick Cheney flew to Tokyo with his closest aides. Newspaper editorials noted the secrecy surrounding his visit - no press conferences, no handshakes with ordinary folks and, as diplomatic cables suggest, no briefing for U.S. Embassy staffers in Tokyo.   Cheney snubbed Defense Minister Fumio Kyuma, who was shut out of confidential talks. The pretext was his criticism of President George Bush for claiming Iraq possessed weapons of mass destruction. The more immediate concern was that the defense minister might disclose bilateral secrets to the Pentagon. The Joint Chiefs of Staff were sure to oppose White House approval of Japan's nuclear program.

Abe has wide knowledge of esoteric technologies. His first job in the early 1980s was as a manager at Kobe Steel. One of the researchers there was astrophysicist Hideo Murai, who adapted Soviet electromagnetic technology to "cold mold" steel. Murai later became chief scientist for the Aum Shinrikyo sect, which recruited Soviet weapons technicians under the program initiated by Abe's father. After entering government service, Abe was posted to the U.S. branch of JETRO (Japan External Trade Organization). Its New York offices hosted computers used to crack databases at the Pentagon and major defense contractors to pilfer advanced technology. The hacker team was led by Tokyo University's top gamer, who had been recruited into Aum.   After the Tokyo subway gassing in 1995, Abe distanced himself from his father's Frankenstein cult with a publics-relations campaign. Fast forward a dozen years and Abe is at Camp David. After the successful talks with Bush, Abe flew to India to sell Cheney's quadrilateral pact to a Delhi skeptical about a new Cold War. Presumably, Cheney fulfilled his end of the deal. Soon thereafter Hurricane Katrina struck, wiping away the Abe visit from the public memory.

Here, based simplified, are the chemical reactions in the atmosphere, which explain how the Fukushima disaster impacted the Arctic ozone hole.   The cold winter in 2010-2011 produced dense stratospheric clouds over the Arctic, which due to the presence of water promoted chemical reactions with various gases to produce compounds that deplete ozone over the Arctic Circle.   The Arctic ozone hole, that began expanding due to the clouds, radically widened in March and April, coinciding with the Fukushima disaster.

"Our results show that Arctic ozone holes are possible even with temperatures much milder than those in the Antarctic," it also said.   It is harder for ozone-destroying chlorine monoxide to form in the stratosphere of the Arctic as winter temperatures are higher than in the Antarctic, according to the group.   But the depletion of the ozone layer over the Arctic appears to have progressed greatly this winter to spring because unusually cold temperatures from December through the end of March enhanced ozone-destroying forms of chlorine.   "The 2010-11 Arctic winter-spring was characterized by an anomalously strong stratospheric polar vortex and an atypically long continuously cold period," the team said in the article contributed to Nature.

From the Mainichi newspaper...   Researchers Report Unprecedented Ozone Loss In Arctic   10-3-11   TSUKUBA, Japan (Kyodo) -- The depletion of the Arctic ozone layer reached an unprecedented level in early 2011 and was "comparable to that in the Antarctic," an international research team said Sunday in the online version of the British science magazine Nature.   "For the first time, sufficient loss occurred to reasonably be described as an Arctic ozone hole," said the nine-country team, including Hideaki Nakajima of the National Institute for Environmental Studies in Tsukuba in Ibaraki Prefecture.

just how far did the radioactive plume travel? On the 27 March Romul Mărgineanu, from the Horia Hulubei National Institute of Physics and Nuclear Engineering (IFIN-HH) in Romania, and colleagues, began to collect samples of rainwater from Braşov and Slănic-Prahova. And on 5 April they also started to collect samples of sheep and goat's milk from the same regions. The samples were all taken to the IFIN-HH's underground laboratory at the Unirea salt mine in Slănic-Prahova, for analysis. Inside this ultra-low radiation environment the levels of iodine131 and caesium137 were measured, using a high resolution gamma-ray spectrometer.

None of the samples contained caesium137 at detectable levels. However, iodine131 was present at up to 0.75 Bq per litre in rainwater, and up to 5.2 Bq per litre in milk. "The level of I-131 in sheep and goat milk was higher than in rain water due to bioaccumulation," explains Mărgineanu. "Bioaccumulation occurs when an organism absorbs a toxic substance – chemical or radioactive – at a rate greater than that at which the substance is lost."

Such levels were two to three orders of magnitude below any intervention limits, for example the limit set for drinking water in Japan was 300 Bq per litre for adults and children and 100 Bq per litre for infants. In this case weather conditions played a role in keeping the radiation levels low. In the weeks following the accident Romania only experienced very light rain; had the rain been heavier more radiation may have been precipitated out. The results are published in Environmental Research Letters.

Using the supercomputer program called SPRINTARS, researchers at Kyushu University and Tokyo University created the simulation of how radioactive materials from Fukushima I Nuclear Power Plant may have dispersed throughout the northern hemisphere. The researcher say their simulation fit the actual measurements. It was published in the Scientific Online Letters on the Atmosphere (SOLA) under the title "A numerical simulation of global transport of atmospheric particles emitted from the Fukushima Daiichi Nuclear Power Plant" in June. You can read the paper at this link (PDF file). You can also view the animation, here, and the press release in Japanese here.

Their simulation also shows, like France's CEREA, radioactive materials from March 14/15 release reached the west coast of North America on March 18. The researchers attribute the rapid dispersion of radioactive materials from Fukushima to the unusually strong jet stream. Also, on March 14/15, there was a low pressure on the east cost of Japan, which created a strong updraft that lifted the radioactive materials to the jet stream. The relative scale is set with the density of radioactive materials at Fukushima I Nuke Plant as 1. By the time it reached North America, it was between 0.000001 and 0.00000001.

An extensive area of more than 8,000 square kilometers has accumulated cesium 137 levels of 30,000 becquerels per square meter or more after the accident at the Fukushima No. 1 nuclear power plant, according to Asahi Shimbun estimates.

The affected area is one-18th of about 145,000 square kilometers contaminated with cesium 137 levels of 37,000 becquerels per square meter or more following the 1986 Chernobyl accident in the former Soviet Union.

The contaminated area includes about 6,000 square kilometers in Fukushima Prefecture, or nearly half of the prefecture. Fukushima Prefecture, the third largest in Japan, covers 13,782 square kilometers.