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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Not even a small tremor verified in Fl...at this time.

Link
Member Since: September 16, 2010 Posts: 0 Comments: 1492
George wasn't an atheist, he said in public that he worshiped the Sun, but he prayed to Joe Pesci.
I am outta here, later...
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Quoting emcf30:
O boy, earthquake fears are running wild. Breaking news story in Orlando, Fl at noon.
BREAKING NEWS
News 13 has received several calls from residents in Flagler County reporting their homes began to shake Friday morning.

Flagler Emergency Operations Center said they are investigating some sort of incident in the Palm Coast area.

The residents said their foundations shook.

Chat LIVE with News 13 about the shaking
Calls continue to come into from all over Flagler County reporting the "tremor".

News 13 contacted the Naval Air Station in Jacksonville, but they are not reporting any bombing range activities.

One resident in the Pine Lakes area reported on News 13's Facebook page her glass windows and sliding glass door vibrating and said there was an "unmistakable roaring rumbling" noise.

Another reported on Twitter, their windows rattled at around 9:30 a.m.

Stay with News 13 and cfnews13.com for updates on this developing story



i am not too far from there and last friday my daughter and i noticed the same thing. several low rumbles and the windows and sliding glass door shaking. never did figure out what it was but since we are so close to nasa I assumed something was happening there.
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Quoting RecordSeason:


Oh no friend, it's a very important existential, philosophical matter of greater importance than anything else really.

"What is a man profited if he gains the whole world, but loses his soul?"

One cannot rest in peace if one is an atheist.

Again, if he was right, then his afterlife is non-existent, or else he's burning in hell because he mocked God continually, and many of you laughed with him.


Who cares?
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Sigh... more trolls than information this morning.

Remember: and move on...

Has there been any official acknowledgment that the spent fuel storage pond in unit 2 has almost certainly been destroyed? I've heard plenty on the news about getting cooling under control for the other ponds, but nobody seems to have acknowledged the very real possibility that the #2 pond was probably scattered across the site by the explosion.

The status of the #2 spent fuel storage pond at wikipedia says "no data". Not exactly encouraging...
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Quoting emcf30:
O boy, earthquake fears are running wild. Breaking news story in Orlando, Fl at noon.
BREAKING NEWS
News 13 has received several calls from residents in Flagler County reporting their homes began to shake Friday morning.[...]
What, more WWII-era munitions blowing up?
Member Since: Posts: Comments:
O boy, earthquake fears are running wild. Breaking news story in Orlando, Fl at noon.
BREAKING NEWS
News 13 has received several calls from residents in Flagler County reporting their homes began to shake Friday morning.

Flagler Emergency Operations Center said they are investigating some sort of incident in the Palm Coast area.

The residents said their foundations shook.

Chat LIVE with News 13 about the shaking
Calls continue to come into from all over Flagler County reporting the "tremor".

News 13 contacted the Naval Air Station in Jacksonville, but they are not reporting any bombing range activities.

One resident in the Pine Lakes area reported on News 13's Facebook page her glass windows and sliding glass door vibrating and said there was an "unmistakable roaring rumbling" noise.

Another reported on Twitter, their windows rattled at around 9:30 a.m.

Stay with News 13 and cfnews13.com for updates on this developing story
Member Since: August 7, 2010 Posts: 0 Comments: 1933
deleted, repeat
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my friends father worked in rincon puerto rico back in the 60 s he experienced radiation burns anyway the dome which was talked about a few days ago on the blog has to have traces of radioactivity still glad it is not in my backyd
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RecordSeason, how can you go from an actual intelligent comment like #69 directly to a rude uncalled-for rant like #72?

I loved George Carlin, I bought his freakin' LPs way back when. George, RIP, right next to your Big Electron.
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Quoting RecordSeason:


I find this statement somewhat humorous, IN a dark and ironic way.

George Carlin cannot rest in peace, he was an atheist.

If his views were correct and there is no God and all Christians are nuts, etc, then his life and death are meaningless and he is not "resting" anywhere. He is a meaningless cosmic accident of no value or consequence whatsoever.


On the other hand, if there is a God, as Christians like my self believe, then George Carlin spent his entire life mocking said God, in spite of having been raised to believe and respect said God, which in turn means that George Carlin is currently being "beaten with many stripes" in Tatartarus (the deepest pit of hell.)


Either way, he is not and cannot be "resting in peace", and his life was a complete waste.


Just trying to figure out some way to post a derogatory response, eh? I'm glad you went to school to learn the art of pulling things out of your bunghole. You must have gotten all A's.
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Quoting txag91met:

When you get a degree in meteorology, it is like having an engineering, physics, or geophysics degree.

At A&M we took 3-4 physics classes, calculus 1-3, differential equations, numerical methods and linear algebra...plus the core dynamics/thermodynamics courses for meteorology.
Differential equations, my favorite.........Posted with a feeling of utter disgust....
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But Oil is still up there, not gonna drop too much looks like

WTI Crude Oil
$101.46 ▲0.04
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George Carlin's way of shooting the moon back at everybody on planet earth.
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Well tomm night is the big moon shot, wonder if/what will happen....Nuttin?
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This is insane


Japan's Meteorological Agency said Friday that the nation has experienced 262 aftershocks of magnitude 5 or greater. That's a record number of aftershocks for any quake in Japanese history, Kyodo News reports.

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Hey Pat, when does NHK come off of recorded mode? I haven't been monitoring it that closely to know. I was just watching and then saw your post and realized it was recorded content.
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just keepin' it fair and balanced.... I never said I stay on topic....
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http://periodictable.com/Elements/005/index.html                                                                                                                                                                                                                              Table of Elements 101
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Ladies and gentlemen the Squawk and Amy folks
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Quoting NRAamy:
RIP George Carlin! We miss you dearly! A pure comic genius...



Thanks for chiming in. Your post really contributed greatly to the discussion. Sarcasm meter on high.


Talk about the pot and the kettle. The queen of worthless posts decides to get in on the action...amazing...
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Quoting Xyrus2000:
[...]
The incidents of radiation sickness at Bikini were not induced by plutonium. it was induced by cesium. Iodine 131 is even more radioactive and due to the way it decays can cause massive cellular damage. The saving grace here is that it has a short half-life of 8 days.
Just to clarify...the danger of having a strong alpha emitter in prolonged close exposure (for example, lodged inside of your lungs) is not so much radiation sickness as it is that you very likely will die of radiation-induced cancer. This is a medical fact that has been well-known since at least the 1940's.
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He also called us the United Strokes Of America...priceless!!!
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Quoting hydrus:
Thank you for posting this..I needed a chuckle and this did it..:)

When you get a degree in meteorology, it is like having an engineering, physics, or geophysics degree.

At A&M we took 3-4 physics classes, calculus 1-3, differential equations, numerical methods and linear algebra...plus the core dynamics/thermodynamics courses for meteorology.
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Quoting RitaEvac:
George Carlin is one of my inspirations and the reason why I think the way I do today.


Just not politically...
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George Carlin is one of my inspirations and the reason why I think the way I do today.
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Quoting RecordSeason:


Nuclear physics really is not that complicated as it is commonly pourtrayed to be. A nuclear expert on television yesterday even said, "This isn't rocket science..."

In terms of equations and thermodynamics, its not all that different than basic chemistry, the only key difference is that "chemistry" happens in the electron orbitals, while "Nuclear chemistry" happens in the nucleus.


Protons, Neutrons, Alpha and Beta particles, etc, are not hard to understand at all.


If what you say is true, how is it that so many on here disagree with each other. Does that mean that one of them is right and all the others are wrong? Or does it mean that none of them know what they are talking about?

Please inform me. I am confused. If it is so easy, they should all be in agreement.
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Quoting Patrap:
I Liked George,,he made me Laugh a lot.

"LaL"


RIP George Carlin! We miss you dearly! A pure comic genius...
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Quoting Jedkins01:


If its simple, why don't you go for a degree in it then?

I once had someone tell me "oh meteorology, its not that bad, thunderstorms are pretty easy to understand".

Then I asked him: well why don't you try and go for a degree since you think its so easy?

He said "well I uh, I'm not very good at math, and physics is really hard."

:)
Thank you for posting this..I needed a chuckle and this did it..:)
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Quoting SQUAWK:
I am absolutely amazed at how many nuclear experts of all kinds we have on this blog.

Doc, you must be very proud and impressed that so may highly educated and knowledgeable experts take the time from their busy lives to comment on this blog.

Truly astounding.


Thanks for chiming in. Your post really contributed greatly to the discussion. Sarcasm meter on high.
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Quoting Xyrus2000:


While I won't comment on the aerosol dispersal, I will comment on the alpha radiation.

Alpha emission are the WEAKEST level of ionizing radiation. Radioactive cesium, strontium, and iodine are BETA and GAMMA emitters. They are also MUCH more radioactive, as are most other high-energy fission by-products. Radioactive cesium 137, for example, which is released in much higher quantities has a half-life of just over 30 years (roughly the same as strontium 90).

The incidents of radiation sickness at Bikini were not induced by plutonium. it was induced by cesium. Iodine 131 is even more radioactive and due to the way it decays can cause massive cellular damage. The saving grace here is that it has a short half-life of 8 days.


Alpha emitters are extremely dangerous if they become incorporated into your body. Radium-226 is a strong alpha emitter with a half-life of ~1600 years. I think we all have heard the stories of the radium watch painters and their gruesome fate, and we also know what caused the death of Marie Curie.
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Quoting RecordSeason:


Nuclear physics really is not that complicated as it is commonly pourtrayed to be. A nuclear expert on television yesterday even said, "This isn't rocket science..."

In terms of equations and thermodynamics, its not all that different than basic chemistry, the only key difference is that "chemistry" happens in the electron orbitals, while "Nuclear chemistry" happens in the nucleus.


Protons, Neutrons, Alpha and Beta particles, etc, are not hard to understand at all.


If its simple, why don't you go for a degree in it then?

I once had someone tell me "oh meteorology, its not that bad, thunderstorms are pretty easy to understand".

Then I asked him: well why don't you try and go for a degree since you think its so easy?

He said "well I uh, I'm not very good at math, and physics is really hard."

:)
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BBC LIVE

Link
Member Since: September 16, 2010 Posts: 0 Comments: 1492
Quoting guygee:
Just plain wrong:


Pu-239 has a half-life of ~24200 years, so it will not be reduced in the plume by fission anytime soon. The fact that it is an intense alpha emitter makes it extremely dangerous if even a tiny particle is inhaled. Just because it is a "heavy" element does not mean that small particles of plutonium cannot be lofted into the plume, that is absurd. Do you even have the slightest background in atmospheric aerosol and particle physics? Do you have any sources to back your claims?

A study of the former open-air French nuclear bomb test site in Algeria found that Pu-239 was present and significantly dispersed. Read for yourself:
Radiological Conditions at the Former French
Nuclear Test Sites in Algeria: Preliminary Assessment
and Recommendations
(pdf)


While I won't comment on the aerosol dispersal, I will comment on the alpha radiation.

Alpha emission are the WEAKEST level of ionizing radiation. Radioactive cesium, strontium, and iodine are BETA and GAMMA emitters. They are also MUCH more radioactive, as are most other high-energy fission by-products. Radioactive cesium 137, for example, which is released in much higher quantities has a half-life of just over 30 years (roughly the same as strontium 90).

The incidents of radiation sickness at Bikini were not induced by plutonium. it was induced by cesium. Iodine 131 is even more radioactive and due to the way it decays can cause massive cellular damage. The saving grace here is that it has a short half-life of 8 days.
Member Since: October 31, 2009 Posts: 0 Comments: 1228

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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.