Trace radioactivity from Japan likely over the Western U.S. today
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
Reader Comments
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Grother.....Loved Cheers, Norm, Carla, And even Kristie Allie
says a lot haha
No picking on the aged (because I could be next)...
Read back if that's all you think I've posted today.
And I cannot image why you would respond to that other one, unless you enjoy the attention, or something.
Weather and climate? Like you've ever believed anything I've posted in that subject matter, even if referenced with peer-reviewed publication...I can post when I like and anything I like that's reasonably on topic.
It was nicer in here before you arrived. And her. And you felt the need to respond. Maybe getting back on topic would help your image.
Breaking News
We should all agree that level heads are always best in any situation.
My Complaint is that I am not hearing any numbers or facts that make sense, except above where 1% is stated. I would like to know a baseline of the different types of normal radiation, what kinds and how much are reaching california and real world examples of short and long term radiation exposure.
Part of the problem is that Americans have lost faith in the integrity of Regulatory Agencies, our Government, and the Nuclear Industry. Most feel that they have betrayed our good faith and trust far too often in the past. This could be an opportunity for them to regain credibility.
But, WTH are you talking about?
fake credentialed blogger posting misinformation which I dont even understand
And I posted no link to WUWT. Not even an image hosted there.
ecmf...I am anti violence , but this needs to be done.I salute Obama on this decision
Seconded. All of what has been going on over there must be stopped, bar none.
like i said
that murdering bastard and he's goons gonna get a just reward they hold that country hostage alot want to speak out but are afraid its time
Remember what Mom said, if you don't have anything nice to say, don't say anything at all...
BTW there is an "ignore user" option...
I think this illistrates how and why America is in trouble, no conflict resolution skills. Divided we are weak, vulenerable, and easily looted and "privatized". The boot-licking Sycophants want to defund NOAA and the rest of our government and privatize everything from regulatory agencies, to education, police and military. from Ca. to Ny. they are looting pensions, defunding government, and outsourcing jobs by the thousands while we bicker over... what?
They Thought They Were Free
http://www.press.uchicago.edu/Misc/Chicago/511928 .html
Good citizens set aside their differences in time of crisis and work togather. ...This may be off on a tangent but if we don't stand togather we are all screwed!
The url you posted results in a 404 error
I can post some picks of the unit if it will help!
What brand is it?
There has been 2 quakes in the last hour moving away from Japan.
6.0 2011/03/20 08:26:11 19.008 121.261 36.6 BABUYAN ISLANDS REGION, PHILIPPINES
5.5 2011/03/20 08:00:51 22.396 121.421 17.3 TAIWAN REGION
Could there be any relation between these quakes and the major Quake and aftershocks?
Another interesting link between the Japan megaquake.
Is this guy serious. The Christchurch quake was only a 6.3, the reason it was so deadly was it's depth and location to a big city. September 4 2010 Christchurch had a 7.1 quake yet it was deeper and further away from Christchurch, hence there was very little damage compared to 3 weeks ago.
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