Trace radioactivity from Japan likely over the Western U.S. today

By: Dr. Jeff Masters , 2:11 PM GMT on March 18, 2011

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Traces of radioactive substances emitted by Japan's damaged Fukushima nuclear power plant will likely arrive over the Western U.S. today, carried by the prevailing west to east winds that have blown over the Pacific Ocean during the past week. Rainfall is expected over California this weekend, and it is likely that the rain will wash radioactive particles out of the air to the surface in quantities that will be detectable at several locations. I want to strongly emphasize that the radioactivity from Japan arriving over the U.S. over the next few days poses absolutely no threat to human health, and is present in only miniscule quantities. The radioactive plumes from Japan have had seven days to dilute over a 5000+ mile journey, and have been subject to deposition to the ocean due to gravity and rainfall along the way. Natural radiation is present in our environment every day, and the extra radiation from the Fukushima nuclear plant will cause much less than a 1% increase this background radiation. Radioactive particles from the Chernobyl disaster in 1986 were detected in North America ten days after that event, and caused no harmful effects. The radiation from Japan over U.S. during the next week should be at levels even lower than the Chernobyl fallout.


Figure 1. Backward trajectories for the air arriving at the surface (red line) and 300 meters altitude (blue line) in San Francisco, California on Saturday, March 19, at 11am PDT. According to the latest run of the GFS model, the air arriving in San Franciso tomorrow will have originated near the surface in northern Japan last Saturday, when radioactive emissions from the Fukushima nuclear plant began. The radioactive particles arriving in California will be in trace quantities, and will have no harmful effects on human health. Images created using NOAA's HYSPLIT trajectory model.

Radioactive plumes emitted from Japan's troubled Fukushima nuclear power plant continue to move offshore to the east over the Pacific Ocean today, thanks to predominantly west winds blowing at 5 - 15 mph. These winds are being driven by the clockwise flow of air around a surface high pressure system centered just southeast of Tokyo. As this high pressure system moves northeastwards, parallel to the Japanese coast, today through Saturday, winds will gradually shift to the southwest, keeping the radiation from the Fukushima plant blowing out to sea. As the winds shift to southwesterly, the sinking air over Japan will be replaced by rising air, and radioactive emissions will begin being lifted high in the atmosphere. Since there is less friction aloft, and the high speed winds of jet stream increase as the air moves higher in the atmosphere, this radiation will undergo long-range transport. Latest trajectory runs using NOAA's HYSPLIT model (Figures 2 - 4) show that radioactivity emitted today could wind up over Alaska after five days, and radioactive particles emitted on Saturday could make it to California by late next week. I've made trajectory plots for the next three days assuming two possible release altitudes--a surface-based release near 10 meters, which should be the predominant altitude in the current situation, and a higher release altitude of 300 meters, which might occur if there is an explosion and major fire. However, the 5-day trek to Hawaii and California is 4000 - 5000 miles, and a tremendous amount of dispersion and dilution of the radioactive plume will occur. Given the current levels of radiation being emitted, any radioactivity reaching Hawaii or the U.S. may be difficult to detect, and will not be a threat to human health. Keep in mind also that the most dangerous radionuclide to human health in the radioactive plume--Iodine-131--has a half life of eight days, so will be reduced by at least 30% after 5 days of travel time.

Of much greater concern is the possibility of dangerous level of radiation over Japan. The next period of onshore winds that will blow radioactivity inland over Japan may occur beginning on Saturday night (U.S. time), continuing through Sunday, according to the latest run of the GFS model. The latest HYSPLIT trajectories show winds on Sunday may carry radiation from the disaster site southwards over Tokyo. A low pressure system is expected to bring considerable rain to Japan on Sunday, and this rain is likely to remove most of the radioactivity from the air where rain and radioactivity are both present. The winds associated with this low are difficult to predict at this time, since the winds will be light and variable.


Figure 2. Five-day forecast movement of plumes of radioactive air emitted at 10 meters altitude (red line) and 300 meters (blue line) at 18 UTC (2pm EDT) Friday, March 18, 2011 from the Fukushima Daiichi nuclear plant. The plumes get caught in a southwesterly flow of air in advance of an approaching low pressure system. The plume emitted near the surface (red line) stays trapped near the surface for 4 days then lifted to 4 km, but the plume emitted at 300 meters is lifted to 5 km altitude after 2 1/2 days by the rising air associated with the approaching low pressure system. Images created using NOAA's HYSPLIT trajectory model.


Figure 3. Five-day forecast movement of plumes of radioactive air emitted at 10 meters altitude (red line) and 300 meters (blue line) at 18 UTC (2pm EDT) Saturday, March 19, 2011 from the Fukushima Daiichi nuclear plant. The plumes get caught in a southwesterly flow of air in advance of an approaching low pressure system and lifted to 4 - 5 km altitude. The plumes are predicted to move over California and Mexico at high altitude. Images created using NOAA's HYSPLIT trajectory model.


Figure 4. One-day forecast movement of plumes of radioactive air emitted at 10 meters altitude (red line) and 100 meters (blue line) at 18 UTC (2pm EDT) Sunday, March 20, 2011 from the Fukushima Daiichi nuclear plant. The plumes get caught northerly winds, and the two lower altitude plumes move over Tokyo by 6 UTC on Monday, March 21. This is a low confidence forecast, as winds are expected to be light and somewhat variable on Sunday over Japan. Images created using NOAA's HYSPLIT trajectory model.

Resources
Seven-day weather forecast for Sendai near the Fukushima nuclear plant

The Austrian Weather Service is running trajectory models for Japan.

Current radar loops from the Japan Meteorological Agency

Jeff Masters

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New York Times Forecast for Plume's Path Animation

http://www.nytimes.com/interactive/2011/03/16/sci ence/plume-graphic.html

Link

A forecast by the Comprehensive Nuclear Test Ban Treaty Organization shows how weather patterns this week might disperse radiation from a continuous source in Fukushima, Japan. The forecast does not show actual levels of radiation, but it does allow the organization to estimate when different monitoring stations, marked with small dots, might be able to detect extremely low levels of radiation. Health and nuclear experts emphasize that any plume will be diluted as it travels and, at worst, would have extremely minor health consequences in the United States.

Health and nuclear experts emphasize that radiation in the plume will be diluted as it travels and, at worst, would have extremely minor health consequences in the United States, even if hints of it are ultimately detectable. In a similar way, radiation from the Chernobyl disaster in 1986 spread around the globe and reached the West Coast of the United States in 10 days, its levels measurable but minuscule.
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I have not seen this number on the news. I hope it is incorrect.

By Laura King, Kenji Hall and Mark Magnier
Los Angeles Times

March 18, 2011, 5:44 p.m.
E-mail Print Share Text Size Reporting from Tokyo and Morioka, Japan— Fighting exhaustion and radiation fears, engineers struggled anew Saturday to complete the crucial task of hooking up a damaged nuclear plant to the electricity grid to help cool damaged reactors. The official count of dead and missing in the quake and tsunami soared above 17,000, making this Japan's worst disaster since World War II.

In the earthquake zone, tears trickled down the cheeks of some survivors and rescue workers as a solemn moment of silence was observed at 2:46 p.m. Friday, marking a week since the magnitude 9 temblor slammed Japan's northeastern coast. The quake set off a chain of events culminating in the nuclear emergency now ranked as a 5 on the 7-point international scale.

Still unknown is whether restoring power to the damaged reactors will significantly aid cooling efforts. The full extent of damage to critical cooling pumps from hydrogen explosions and corrosion from seawater that has been pumped in has not been assessed.

Member Since: July 17, 2009 Posts: 69 Comments: 25378
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newk, nook, nouque....

do gnomes have gnukes?

(ducks as twinC throws shoe)
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527. HadesGodWyvern (Mod)
A Cyclone Warning Class I is in force for Rodriques Island
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Just saw some images of the workers at the plant in Japan, (zoom lens,no doubt) They are some brave souls. The world, as well as Japan, owes them our deepest respect and admiration.
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525. flsky
Great video - thanks for posting!
Quoting Skyepony:
Small cloud funnel touched down @ San Francisco - Ocean Beach

Wunder how far this was from our servers devs & such.

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The gun subsystem employs a gatling gun consisting of a rotating cluster of six barrels. The gatling gun fires a 20mm subcaliber sabot projectile using a heavy-metal (either tungsten or depleted uranium) 15mm penetrator surrounded by a plastic sabot and a light-weight metal pusher. The gatling gun fires 20mm ammunition at either 3,000 or 4,500 rounds-per-minute with a burst length of continuous, 60, or 100 rounds.

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522. Skyepony (Mod)
Small cloud funnel touched down @ San Francisco - Ocean Beach

Wunder how far this was from our servers, devs & such.

Member Since: August 10, 2005 Posts: 161 Comments: 37388
521. flsky
Nothin' wrong with that!
Quoting Grothar:


Amazing isn't it. I can't bend my head back far enough to look up at it, so I have to lie on my back to get a good view.
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Quoting atmoaggie:
I really like this new layout on WU. Very nice.


Give me T, give me a W..........
Member Since: July 17, 2009 Posts: 69 Comments: 25378


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518. HadesGodWyvern (Mod)
Mauritius Meteorological Services
Tropical Disturbance Advisory #16
TEMPETE TROPICALE MODEREE CHERONO (07-20102011)
4:00 AM RET March 19 2011
==========================================

At 0:00 AM UTC, Moderate Tropical Storm Cherono (995 hPa) located at 17.5S 68.4E has 10 minute sustained winds of 35 knots with gusts of 50 knots. The cyclone is reported as moving west southwest at 13 knots.

Gale Force Winds
===============
40 NM from the center extending up to 70 NM in the southern semi-circle

Near Gale Force Winds
=======================
50 NM from the center extending up to 70 NM in the northeastern quadrant and up to 300 NM in the southern semi-circle due to gradient effect

Dvorak Intensity: T2.0/2.5/W1.0/24 HRS

Forecast and Intensity
======================
12 HRS: 18.6S 65.7E - 40 knots (Tempête Tropicale Modereé)
24 HRS: 19.5S 62.8E - 40 knots (Tempête Tropicale Modereé)
48 HRS: 21.4S 57.2E - 30 knots (DEPRESSION Tropicale)
72 HRS: 23.3S 53.0E - 25 knots (PERTURBATION Tropicale)

Additional Information
=====================

Infrared satellite imagery shows an asymmetrical structure with convection existing mainly in the south of the system. ASCAT METOP pass 1722z confirms this asymmetry with strong winds extending far away towards the south and clearly weaker in the northern part of the system. Low level center is very difficult to localize and also Dvorak analysis is delicate. Moderate Tropical Storm status is maintained in view of pass ASCAT winds.

Numerical Weather Prediction models remain in rather good agreement for a west southwestward track on the northern edge of the low to mid levels subtropical ridge within the next 72 hours. With upper levels environmental conditions remaining favorable until the end of the day Saturday, system should slightly re-intensify before to undergo a strengthening northwesterly wind shear ahead of a deep mid latitude trough.

After 72 hours, some of models forecast a southward recurvature and other models continue to track the system west southwestward. At day 4 and 5, and according to Numerical Weather Prediction fields, a strong weakness should appear within the subtropical ridge ahead of the system and might result in a southward turn of the residual low.

UNHABITANTS OF RODRIGUES ISLAND SHOULD CLOSELY MONITOR THE PROGRESS OF THIS SYSTEM AS IT SHOULD PASS VERY CLOSE OR OVER THE ISLAND SATURDAY NIGHT.

The next tropical cyclone advisory from Mauritius Meteorological Services will be issued at 6:30 AM UTC..
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Quoting alfabob:
Doesn't really prove much when you let the people being reviewed do the reviewing..
Agreed. And in any field, not just this one...
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Japan's pro baseball league says it will continue with season, which starts soon; no night games to preserve energy
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Quoting twincomanche:


I suggest further research.


Here is a description of depleted uranium:
http://en.wikipedia.org/wiki/Depleted_uranium

Not part of the wasted from a nuclear reactor but it is waste from the preparation of U-235 which is one of the materials used in nuclear weapons and nuclear reactor core rods. It is not totally hazard free.
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..."Fly me to the Moon"....
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506. Skyepony (Mod)
Workers at Japanese Nuclear Plant Finally Get A Robot Assistant
Member Since: August 10, 2005 Posts: 161 Comments: 37388
Quoting Grothar:


I had to go back to Classic view. The only place it will work. The next person who says how good this new version is, I'll.......well, being a gentleman, I can't say it on the blog. Think this strange new moon has anything to do with it?
I really like this new layout on WU. Very nice.
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Press Release

IAEA Press Release

Radiological Impact of the Use of Depleted Uranium Ammunition


2001 | 31 January 2001 | Concerns have been expressed about the possible health and environmental consequences of exposure to depleted uranium (DU) arising from the use of this material in ammunition some ten years ago in the Gulf and subsequently in the Balkans. This exposure would have been caused by external radiation arising from DU or by the inhalation, ingestion or intake through wounds of DU spread in the environment. It has also been suggested that adverse health effects, notably leukaemia and other forms of cancer, could be attributable to such exposure.

Uranium is a naturally occurring radioactive material; its three principal radioactive isotopes are U-238, U-235 and U-234. One of the by-products of the process of uranium enrichment is DU that is comprised almost entirely from U-238 isotopes. It is about 60% as radioactive as natural uranium. Physically and chemically, DU behaves in the same way as natural uranium .

T he IAEA has statutory responsibilities for establishing standards for the protection of health against exposure to ionising radiation and for providing for the application of these standards at the request of any State. In fulfilment of these functions, the Agency has established a comprehensive corpus of radiation safety standards in close collaboration and consultation with other relevant organizations in the United Nations system. The International Basic Safety Standards for Protection against Ionising Radiation and for the Safety of Radiation Sources (Basic Safety Standards), which were established jointly with the International Labour Organization (ILO) and other international organizations including the World Health Organization (WHO), are the authoritative radiation protection standards for assessing the potential radiological impact of the uses of DU. The exposures to which the requirements of the Basic Safety Standards apply are any occupational exposure, medical exposure or public exposure. However, they only cover risks of radiation and do not cover the toxic risks that may be associated with uranium intake. In the past, the IAEA, based on its statutory mandate and competence has prepared comprehensive scientific radiological impact assessments.

In May 1999, at the request of the Secretary-General of the United Nations, the United Nations Environment Programme (UNEP) established a Balkan Task Force (BTF) with a view to carrying out an environmental impact assessment of the Balkans conflict. As it has been concluded that one of the issues to be addressed is the possible consequences of the use of depleted uranium ammunition in the conflict, UNEP has initiated fact finding missions to Kosovo in order to identify the magnitude of the problem. At the invitation of UNEP, experts of the IAEA have participated in this work. Most recently, in November 2000, the Agency's experts participated in a fact finding mission to Kosovo, led by UNEP and supported by the United Nations Interim Administration Mission in Kosovo (UNMIK) and NATO. The team that comprised 14 experts from Finland, Italy, Switzerland, USA, Sweden, the United Kingdom as well as UNEP and the IAEA, visited 11 sites where, according to information provided by NATO, DU ammunition has been used, carried out initial measurements and took samples of soil, water, vegetation and cow's milk. These samples are currently being analysed in European laboratories, including the Agency's Laboratories at Seibersdorf.

Notwithstanding the ongoing work referred to above, information available to the Agency on the levels and precise location of DU contamination in the territory of Yugoslavia is limited. The level of research carried out so far is not yet sufficient to warrant a scientific conclusion and, therefore, further work, including additional field mission(s) will be required. The objective of the assessment should be to make a comprehensive survey of the area and of the people and make recommendations from the point of view of toxic and radiological safety at specific locations in Kosovo where depleted uranium may have been spread. At the request of the States concerned, the IAEA is prepared to continue to contribute its scientific know-how and experience to clarify the radiological impact of the use of DU ammunition in the Balkans.

For more information visit the web site of UNEP - Balkans or read the WHO factsheet on depleted uranium.
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Japan Red Cross

Methods for detecting radiation:

Scintilation Counter (gamma and xray)

Geiger counter (gamma and beta, sometimes alpha)

Proportional Counter (alpha, beta)




Ionizing radiation comes in many flavors. The energy of the radiation is as important as the type. For example, beta can be stopped by a very thin shield. But if the shield is a dense material and the beta is energetic then stopping the beta will produce a shower of gamma radiation called braking radiation. So beta is shielded with plexiglass which slowly stops the beta and avoids the gamma production. Alpha can be stopped by dead skin. Neutrons are not ionizing per se because they don't interact with matter very well, but when they collide with a nucleus they can produce secondary radiation.

Link

Early radiation detectors were very simple affairs. Something called a gold leaf electrometer was once used to detect ionizing radiation. These can be built at home easily.

Electrometer
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18 March 2011, Graham Andrew, Special Adviser to the IAEA Director General on Scientific and Technical Affairs, today briefed the Agency's Member States on the nuclear emergency in Japan following last week's devastating earthquake

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Quoting Grothar:


Amazing isn't it. I can't bend my head back far enough to look up at it, so I have to lie on my back to get a good view.

where is this?

Still sunny out in california
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Quoting flsky:
Just went out to take a look - gorgeous. Hope to go out on the beach tomorrow to see it rise from the sea.


Amazing isn't it. I can't bend my head back far enough to look up at it, so I have to lie on my back to get a good view.
Member Since: July 17, 2009 Posts: 69 Comments: 25378
Quoting Grothar:




On March 19, Earth%u2019s satellite will be at its closest point to our planet in 18 years -- a mere 356,577 kilometers away. The event -- also called a lunar perigee -- was dubbed a "supermoon" by astrologer Richard Nolle back in the 1970s. The term is used to describe a new or full moon at 90% or more of its closest orbit to Earth. Next week, it will be at 100%. This was from last week

Link
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Awesome Moon Rising Uptown here this evening.

Gaw-gus really
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491. flsky
Just went out to take a look - gorgeous. Hope to go out on the beach tomorrow to see it rise from the sea.
Quoting Grothar:




On March 19, Earth’s satellite will be at its closest point to our planet in 18 years -- a mere 356,577 kilometers away. The event -- also called a lunar perigee -- was dubbed a "supermoon" by astrologer Richard Nolle back in the 1970s. The term is used to describe a new or full moon at 90% or more of its closest orbit to Earth. Next week, it will be at 100%. This was from last week

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Quoting KEEPEROFTHEGATE:
what strange moon




On March 19, Earth%u2019s satellite will be at its closest point to our planet in 18 years -- a mere 356,577 kilometers away. The event -- also called a lunar perigee -- was dubbed a "supermoon" by astrologer Richard Nolle back in the 1970s. The term is used to describe a new or full moon at 90% or more of its closest orbit to Earth. Next week, it will be at 100%. This was from last week

Link
Member Since: July 17, 2009 Posts: 69 Comments: 25378
Quoting GeoffreyWPB:
Things are screwed up using IE, but okay on Firefox.

makes sense, I use firefox.

IE users should really consider switching to firefox or google chrome, they're both much faster and safer.
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were gonna need a 12mm wrench and a piece of PVC and a Pump Gear washer lock pin,,..

,,not a Clarkman though


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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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