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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Quoting washingtonian115:
I like weather jokes,and celeberty jokes. This certainly spells trouble this up coming season.I wonder how the 2011 hurricane map will look like once november comes...


The higher than normal SST's and well below average wind shear tells me we have a higher than normal chance of a TS in May, and an active July.
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234. Skyepony (Mod)
Levi~ there was a good ASCAT pass of the wave on the equator yesterday. Impressive for being at 0ºN. Like the air was coming straight down in one spot, then going out in all directions at the surface.
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Quoting Levi32:


Tropical waves do not form in the Caribbean. They form over Africa, and are actually aided by wind shear, not hindered.

But yes, wind shear is well below normal in the tropical Atlantic.



Thanks for correctingme on that... Noticed there is no wind shear in the ATL

Then, that means that we could experience a strong CV season?
Member Since: August 2, 2010 Posts: 21 Comments: 9821
5.45am The Australian's James Madden reports on an ongoing humanitarian crisis that has been overshadowed by nuclear fears:

They don't know when, or from where, their next meal is coming. They don't know how long they will be sleeping on the floors of schools and gyms. They don't know if they are far enough from the damaged Fukushima plant to be safe from harm.

There is no power, daytime temperatures are well below zero and illness is taking hold. And all this while many of them are also dealing with the loss of loved ones.

5.40am A new report suggest Friday's tsunami would have been the biggest ever to hit Japan if it wasn't for a coastal levee. It's been calculated at 23m - Japan's biggest was 38.2m high in 1896.

5.26am Save the Children's Steve McDonald estimates 100,000 children are now homeless in Japan

"We're already seeing families huddling around gas fires for warmth. In these sorts of temperatures, young children are vulnerable to chest infections and flu."

Member Since: August 2, 2010 Posts: 21 Comments: 9821
Quoting Levi32:
The weakening of the La Nina in the Pacific is allowing more convection in the central-eastern equatorial Pacific, causing the re-birth of the subtropical jetstream funneling into Mexico.

If we go into netrual mode Levi the U.S better hang hong.I also wouldn't be surprised to see some early spinners close to home this season.
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Quoting auburn:
I remember a time on these blogs when folks would bend over backwards to help out another blogger...

I dont remember how to do it 1911...but I will see if I can figure it out and message you.





Should you look at my avitar it would soon become obvious that I am not the one that answer that question.
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Bro, RecordSeason, get a life and get off this blog. Hope admin takes care of this fool...and they did, finally.
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I just looked at the temps comparison between KW and Va. Beach. Va. Beach is now at a warm 83.2 degrees F compared to KW at 81 degrees. Raleigh is 81.2F All thanks to WU for the info.
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Quoting Grothar:


Skypony is, and always will be a class act. Nice of you to point it out on the blog.


YES! Consistently a source of informative and useful posts both on weather and the environment! Thanks Skye!
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thankfully, back to tropical weather talk. I've had enough of all the nuclear/meteorologist/global warming/climatologist all in one experts in here.
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Comic......

Plutonium is 1000x less toxic than Botox (and other science facts)

http://www.smartplanet.com/technology/blog/scienc e-scope/plutonium-is-1000x-less-toxic-than-botox-a nd-other-science-facts/6535/
Link

Please do not blame me, some one asked for humor. :)
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The weakening of the La Nina in the Pacific is allowing more convection in the central-eastern equatorial Pacific, causing the re-birth of the subtropical jetstream funneling into Mexico.

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Quoting kwgirl:
You are right about the options, but how do you know that insulted the recipient? Besides weather info, I come on the blog for comic relief, don't you?
I like weather jokes,and celeberty jokes.
Quoting Levi32:


Tropical waves do not form in the Caribbean. They form over Africa, and are actually aided by wind shear, not hindered.

But yes, wind shear is well below normal in the tropical Atlantic.

This certainly spells trouble this up coming season.I wonder how the 2011 hurricane map will look like once november comes...
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Quoting MagicFan:
Anybody have a map showing the above average SST in the Gulf and Caribbean? I must say the SST temps around FL are the warmest I've seen this early in quite sometime. SST at Daytona are in the low 70's and it's only mid March. We didn't see the SST this warm until early May of last year here.


There were a couple of them put up earlier in the blog. Go to the previous page. The people on this blog are an excellent source of information.
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The good ole US of A is warming up, right on cue.
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Quoting kwgirl:
After looking at the pictures, how can you think anything is left? Sure, I know they have to try, but I think the Japanese realize they are out of time.


They have also talked about bringing in additional pumps to connect up. They still have pressure in the reactor vessels, so there is still hope.
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Quoting sunlinepr:
Looks like there is almost no wind shear in the Caribbean to inhibit TWave formation...?



Tropical waves do not form in the Caribbean. They form over Africa, and are actually aided by wind shear, not hindered.

But yes, wind shear is well below normal in the tropical Atlantic.

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Quoting Patrap:
(Daily Mail Reporter) The boss of the company behind the devastated Japanese nuclear reactor today broke down in tears – as his country finally acknowledged the radiation spewing from the over-heating reactors and fuel rods was enough to kill some citizens






After Tokyo Electric Power Company Managing Director Akio Komiri cried as he left a conference to brief journalists on the situation at Fukushima, a senior Japanese minister also admitted that the country was overwhelmed by the scale of the tsunami and nuclear crisis.

He said officials should have admitted earlier how serious the radiation leaks were.

Chief Cabinet Secretary Yukio Edano said: ‘The unprecedented scale of the earthquake and tsunami that struck Japan, frankly speaking, were among many things that happened that had not been anticipated under our disaster management contingency plans.

‘In hindsight, we could have moved a little quicker in assessing the situation and coordinating all that information and provided it faster.’

Nuclear experts have been saying for days that Japan was underplaying the crisis’ severity.
Ouch.Their dealing with a double wammy over in Japan.As if the earthquake and Tsunami wern't enough.This disaster will probally the most talked about in Japan for years,and years,and generations to come.
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Quoting washingtonian115:
Insted of insulting the person it would be best to put them on ignore or skip over their post.Their is also the report feature which can come in handy as well.Using these three options will help you lessen a chance of getting a banf or some one who you think is not worth your time.
You are right about the options, but how do you know that insulted the recipient? Besides weather info, I come on the blog for comic relief, don't you?
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Quoting Floodman:
I would like to take a moment and compliment skyepony's ability to ignore all the ridiculous "material" that gets flung around in here...always steady, skyepony's posts are informative, well thought out and the depth of web based information displays incredible patience and tenacity in researching nearly anything...


i have to agree plus the fact that i have research the info given to fully understand his posts. it is HIS right??
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Looks like there is almost no wind shear in the Caribbean to inhibit TWave formation...?

Member Since: August 2, 2010 Posts: 21 Comments: 9821
Quoting hurricanejunky:


Your E-Harmony match report came back...Glenn Beck is your soul mate...have a great weekend!
Insted of insulting the person it would be best to put them on ignore or skip over their post.Their is also the report feature which can come in handy as well.Using these three options will help you lessen a chance of getting a banf or some one who you think is not worth your time.
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Quoting hurricanejunky:


Your E-Harmony match report came back...Glenn Beck is your soul mate...have a great weekend!
ROFLMAO!!!!!
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Quoting jitterboy:
I think Some1Has2BtheRookie,RecordSeason, and the Publix bag boy/shirtless jail bait kid from yesterday are the same person.


HILARIOUS!!! LOL!!!

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Quoting nrtiwlnvragn:


One step at a time, if there is equipment that could be helpful the first step is to get power to it.
After looking at the pictures, how can you think anything is left? Sure, I know they have to try, but I think the Japanese realize they are out of time.
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Quoting MagicFan:


Them dems don't seem so bright afterall. Drill baby drill is what I say!


Whatever you say CFLWX
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Quoting sunlinepr:


Hey RecordSeason, my friend;
In my opinion, you sound like a Christian who is very jealous of your faith and following God's principles...

But this is not the place for exposing your beliefs cause this is a weather blog


Ecclesiastes Chapter 3 even teaches us that...

A Time for Everything
1 There is a time for everything,
and a season for every activity under the heavens:

3 a time to tear down and a time to build,

5 a time to embrace and a time to refrain from embracing,

7 a time to tear and a time to mend,
a time to be silent and a time to speak,

8 a time to love and a time to hate,
a time for war and a time for peace


There is a Record Season... turn turn ah the Byrds
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Quoting MagicFan:


Them dems don't seem so bright afterall. Drill baby drill is what I say!


Some people on here. Sigh..........
Member Since: October 8, 2008 Posts: 14 Comments: 4553
Quoting kwgirl:
That's like hooking up power to your house meter AFTER the tornado took the house away. You got power, but how are you going to use it?


One step at a time, if there is equipment that could be helpful the first step is to get power to it.
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Quoting RecordSeason:


Most people who think they know the Bible know nothing of it.

....


Hey RecordSeason, my friend;
In my opinion, you sound like a Christian who is very jealous of your faith and following God's principles...

But this is not the place for exposing your beliefs, cause this is a weather blog


Ecclesiastes Chapter 3 even teaches us that...

A Time for Everything
1 There is a time for everything,
and a season for every activity under the heavens:
3 a time to tear down and a time to build,
5 a time to embrace and a time to refrain from embracing,

7 a time to tear and a time to mend,
a time to be silent and a time to speak,

8 a time to love and a time to hate,
a time for war and a time for peace

I won't do it, but some bloggers here are going to put you on ignore... That's my opinion...
Member Since: August 2, 2010 Posts: 21 Comments: 9821
195. auburn (Mod)
I remember a time on these blogs when folks would bend over backwards to help out another blogger...

I dont remember how to do it 1911...but I will see if I can figure it out and message you.


Quoting 1911maker:
can some one please tell me how to change my avatar?
the orginal one got lost and replaced by a picture that is not.

thanks in advance...
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193. beell
Radiation Readings outside the 20km Evacuation Zone/Ministry of Education, Culture, Sports, Science and Technology (MEXT) March 17th

Highest reading at monitoring station 32. Approx 30km NW of Fukushima.
170 microsieverts.

MEXT appears to be tasked with a wide variety of items!


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Quoting nrtiwlnvragn:
TEPCO connects line, can supply power to Daiichi plant
That's like hooking up power to your house meter AFTER the tornado took the house away. You got power, but how are you going to use it?
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What we need to do is to go to coal. Then we won't have any issues with radioactivity.

Coal is Safe! Yippy!
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Quoting Skyepony:
Thanks Flood..I resist steering ya'll down roads like phonetically sounding out some of the names of these Japanese places of disaster (well most of the time)..

ILwthrfan~ I don't know if there is a timelime. Looks like some shallow, hard quakes happened on Fujiyama. Not finding alot about it yet, nothing from an agency. The spins remind me of the storm surge of fire scenario with the oil spill. In a few days when the wind is right...blowing huge amounts of radiation toward the volcano.. It blows it sky high in a massive volcano explosion.. quickly across the earth. Burning ash covering Tokyo, Fukushima & other reactors..doom(of the moon).


You're welcome (though thanks were not necessary; it was well deserved praise)...

As for the Fuji-about-to-explode issue, you're right: regardless of the event there are always some "scientists" who predict final dissolution for the human race (or the Gulf coast, or Washington state or *insert favortie locale upon which to visit biblical destruction here*)...

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can some one please tell me how to change my avatar?
the orginal one got lost and replaced by a picture that is not.

thanks in advance...
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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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