Onshore winds push radioactivity towards Tokyo

By: Dr. Jeff Masters , 1:54 PM GMT on March 21, 2011

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Radioactive plumes emitted from Japan's troubled Fukushima nuclear power plant are headed to the southwest towards Tokyo today, carried by onshore northeasterly winds. An elongated area of low pressure is located off the southeast coast of Japan, and the counter-clockwise flow of air around this low may bring several periods of onshore northeasterly winds through Tuesday to northern Japan. According to the latest trajectory plots from NOAA's HYSPLIT model, air moving towards Tokyo today will be lifted by the ascending air associated with the low pressure system, and the radioactive particles may not make it all the way to Tokyo before getting lifted high enough that they get caught in a strong upper-level flow of air from the southwest and carried out to sea. Latest radar loops from the Japan Meteorological Agency show a wide region of light rain affecting Tokyo and surrounding regions, and this rain will tend to remove the great majority of the radioactive particles from the air in a few hours, so it is uncertain how much radioactivity might make it to Tokyo. High pressure will begin building in on Tuesday over Japan, and wind will gradually shift to blow out the north, which would carry radioactivity offshore just to the east of Tokyo. Offshore winds are expected on Wednesday, but onshore winds could re-develop late in the week as a new weak low pressure system affects the region. Radiation at the levels being reported coming from the troubled plant are not high enough to be of concern to human heath outside of Japan, so I will not be posting further plots showing the long-range path of the radioactivity unless there is a major explosion resulting in a significant release of radioactive emissions.


Figure 1. 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) Monday, March 21, 2011 from the Fukushima Daiichi nuclear plant. The plumes get blown by northeasterly winds close to Tokyo, before getting lifted high enough to get caught in a strong flow of air from the southwest that carries the radioactive air out to sea. Image created using NOAA's HYSPLIT trajectory model.


Figure 2. 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) Tuesday, March 22, 2011 from the Fukushima Daiichi nuclear plant. Northerly winds are predicted to carry radioactivity just to the east of Tokyo. A modest wind shift could bring the radioactivity to the city. Image 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 Drakoen:


That is a real possibility. A weak La-Nina. I looked at the CFS and GloSea model which takes us into neutral with a cool bias with the given rate of warming. An interesting thing to note is that the GloSea underestimated the rate of warming in its 3-month lead forecast. If we consider the Glosea to be an underestimation and the ECMWF members to be an overestimation then perhaps need to take the mean of the total ECMWF members and the Glosea members which I would see as a neutral with a slight warm biased which I think is what we will be looking at this hurricane season.

The March 2011 IRI ENSO forecast models have the average among the all dynamic models right around neutral, so this season could be absolutely neutral.



The very close agreement of the dynamical and statistical models strengthens the case for neutral conditions, with MJJ as the first 3-month period clearly above -0.5. We may be looking at neutral conditions for most or all of the season.

This "technical report" from 2002 has some interesting conclusions regarding regional disposition of LANDFALLING hurricanes under El Nino/La Nina/neutral conditions. I don't see it cited much. Reading the conclusions is a good way to spend 10 minutes, although the entire paper is interesting to my non-expert eyes:

FSU COPS landfalling hurricanes and ENSO

Expert commentary anyone?
Member Since: July 15, 2005 Posts: 3 Comments: 1267
Quoting SouthDadeFish:
The zonal pattern we have been seeing across the US recently is more reminiscent of an El Nino pattern instead of La Nina.


U.S. temperatures so far in March are very La Nina-ish. It was more El Nino-like during the heart of the winter when it was cold in the eastern US.

Member Since: November 24, 2005 Posts: 635 Comments: 26647
It can get messy in the summer because everything pulls north, and in positive NAO summers you can have four main belts of 200mb wind anomalies. Again, more depends on the actual pattern than the NAO numerical value, as it can represent many different things in the summer season.

Member Since: November 24, 2005 Posts: 635 Comments: 26647
Quoting Drakoen:


As far as modeling is concerned, each red line is an individual ensemble member and each member is set with sightly slightly different conditions. As we go out in time and the error increases we can see a deviation among the ensemble members. The graph above shows a general trend of the NAO going upwards. A negative NAO means a stronger than normal subtropical high which increases the low level winds. With wind shear we are concerned about the the winds at 850mb and 200mb and the difference between them. Strong wind speeds at 850mb as a result of a positive NAO is generally not favored. The strong unidirectional winds make it difficult for tropical waves to get a circulation going.


Thanks for the explanation, Drak. I know this has come up before, but I can't always remember which affects what.
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The zonal pattern we have been seeing across the US recently is more reminiscent of an El Nino pattern instead of La Nina.
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Quoting Drakoen:


As far as modeling is concerned, each red line is an individual ensemble member and each member is set with sightly slightly different conditions. As we go out in time and the error increases we can see a deviation among the ensemble members. The graph above shows a general trend of the NAO going upwards. A negative NAO means a stronger than normal subtropical high which increases the low level winds. With wind shear we are concerned about the the winds at 850mb and 200mb and the difference between them. Strong wind speeds at 850mb as a result of a positive NAO is generally not favored. The strong unidirectional winds make it difficult for tropical waves to get a circulation going.


This is true, though 200mb winds generally show easterly anomalies as well, and the overall correlation is for less shear. Also, in the actual hurricane season, AO/NAO signals are more fuzzy, meaning that a positive or negative value can mean many different things pattern-wise. However, in general, a positive NAO during the summer is actually favorable overall if the AMO is warm, because the stronger trade winds are pulled north of the deep tropics, allowing fairly light winds and increased cyclonic vorticity due to the easterlies to the north.
Member Since: November 24, 2005 Posts: 635 Comments: 26647
Quoting BahaHurican:
Levi, that makes me remember 2006, where the forecasted shift to el nino was not believed, resulting in massive over-forecasting of NS.... I don't think we're going to see as strong a shift this year, based on most of what I've seen. I'm thinking the warm anomalies in post 133 are more likely to bring us to neutral, rather than substantially into el nino territory.


If the SOI remains high that could very well be the case.
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Quoting BahaHurican:
Levi, that makes me remember 2006, where the forecasted shift to el nino was not believed, resulting in massive over-forecasting of NS.... I don't think we're going to see as strong a shift this year, based on most of what I've seen. I'm thinking the warm anomalies in post 133 are more likely to bring us to neutral, rather than substantially into el nino territory.


I would agree. 2006 was different because it was in a warm PDO period, but we're now in a cold PDO period, making it more difficult for El Ninos to develop and last, especially in a full reversal out of a strong La Nina.
Member Since: November 24, 2005 Posts: 635 Comments: 26647
Quoting Grothar:


I will try. In this graph which shows the AO through March 2011, the end of it has red lines going all over the place. Does the AO affect the wind shear in the Atlantic? If so, would a positive AO indicated more or less shear in the Atlantic.



As far as modeling is concerned, each red line is an individual ensemble member and each member is set with sightly slightly different conditions. As we go out in time and the error increases we can see a deviation among the ensemble members. The graph above shows a general trend of the NAO going upwards. A negative NAO means a stronger than normal subtropical high which increases the low level winds. With wind shear we are concerned about the the winds at 850mb and 200mb and the difference between them. Strong wind speeds at 850mb as a result of a positive NAO is generally not favored. The strong unidirectional winds make it difficult for tropical waves to get a circulation going.
Member Since: October 28, 2006 Posts: 57 Comments: 30494
Levi, that makes me remember 2006, where the forecasted shift to el nino was not believed, resulting in massive over-forecasting of NS.... I don't think we're going to see as strong a shift this year, based on most of what I've seen. I'm thinking the warm anomalies in post 133 are more likely to bring us to neutral, rather than substantially into el nino territory.
Member Since: October 25, 2005 Posts: 19 Comments: 22140
The Australian BOM's model has also trended warmer and is now calling for weak El Nino conditions by the A-S-O period. Too early to speculate how this would effect the latter part of Hurricane Season.

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Quoting Grothar:


I will try. In this graph which shows the AO through March 2011, the end of it has red lines going all over the place. Does the AO affect the wind shear in the Atlantic? If so, would a positive AO indicated more or less shear in the Atlantic.



Less. Notice what happened to the wind shear in mid-January when the AO reversed from negative to positive. It has been averaging well below normal since then.

Notice the Caribbean shear coming up in recent weeks although the AO has still been positive. This may be indicative of the subtropical jet strengthening as convection increases slowly in the central/eastern equatorial Pacific as nino SSTs rise.



Member Since: November 24, 2005 Posts: 635 Comments: 26647
CFS has jumped to warm-biased neutral or weak El Nino.

Member Since: November 24, 2005 Posts: 635 Comments: 26647
Quoting GeoffreyWPB:


My glass of water is always half full.
What, do u never drink it all at one time?
Member Since: October 25, 2005 Posts: 19 Comments: 22140
Quoting Drakoen:


That is a real possibility. A weak La-Nina. I looked at the CFS and GloSea model which takes us into neutral with a cool bias with the given rate of warming. An interesting thing to note is that the GloSea underestimated the rate of warming in its 3-month lead forecast. If we consider the Glosea to be an underestimation and the ECMWF members to be an overestimation then perhaps need to take the mean of the total ECMWF members and the Glosea members which I would see as a neutral with a slight warm biased which I think is what we will be looking at this hurricane season.

The March 2011 IRI ENSO forecast models have the average among the all dynamic models right around neutral, so this season could be absolutely neutral.

Hmmm.... neutral with possible cold bias is worst case scenario landfall-wise, IIRC.... Also supports the forecasts of above-average. Someone was also posting windshear trend analysis the other day implying below average windshear forecasts for the early part of the season....
Member Since: October 25, 2005 Posts: 19 Comments: 22140
Drakoen, as much as I would like to believe ENSO models on a neutral conditions during Hurricane Season you cannot ignore the large build up of above normal anomalies below the surface in the Nino 3.4 region in recent weeks. Especially with the above normal anomalies quickly eroding the below normal amomalies from below & from west to east. I'm not saying were on the way to El Nino which would be a bit ambitious considering the extent of below normal anomalies remain in the equatorial Pacific and the SOI remains very high. Its just something I'd like to point out.

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Quoting TampaSpin:


Not really!! He gets in trouble on here about as much as myself! Just sayn..LOL


Gee, I've never seen you get in trouble much, unless you count all of 2010. LOL
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Quoting Drakoen:


Could you be more specific?


I will try. In this graph which shows the AO through March 2011, the end of it has red lines going all over the place. Does the AO affect the wind shear in the Atlantic? If so, would a positive AO indicated more or less shear in the Atlantic.

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Figure 1. The number of hurricanes that made landfall in Florida each year between 1900 and 1998. El Niño years are indicated in red, neutral years are shown in green and La Niña years are indicated in blue.



Figure 2. The number of hurricanes that made landfall along the East Coast each year between 1900 and 1998. El Niño years are indicated in red, neutral years are shown in green and La Niña years are indicated in blue.

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Quoting Grothar:


Drak, any idea why the graph on the AO goes haywire at the end of March 2011. POST 115. Can't find an explanation. How much might that affect wind shear in the coming months, if any.


Could you be more specific?
Member Since: October 28, 2006 Posts: 57 Comments: 30494
Quoting Grothar:


Always the optimist. Can't you be an alarmist just once and say we are drying up and no water will be available and get a good argument doing. You always have to play the nice guy.


Not really!! He gets in trouble on here about as much as myself! Just sayn..LOL
Member Since: September 2, 2007 Posts: 178 Comments: 20439
Quoting Drakoen:


Neutral years tend to yield an above-average number storms.


Drak, any idea why the graph on the AO goes haywire at the end of March 2011. POST 115. Can't find an explanation. How much might that affect wind shear in the coming months, if any.
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Quoting Grothar:


And the other half is filled with what?


Clamato.
Member Since: September 10, 2007 Posts: 0 Comments: 11159
Quoting GeoffreyWPB:


My glass of water is always half full.


And the other half is filled with what?
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Quoting Some1Has2BtheRookie:



True. Very true, Tampa. I stand corrected.

Hey, Grothar. What is with all the aliases?


Many Live, Many Masters.
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Quoting Grothar:


Always the optimist. Can't you be an alarmist just once and say we are drying up and no water will be available and get a good argument doing. You always have to play the nice guy.


My glass of water is always half full.
Member Since: September 10, 2007 Posts: 0 Comments: 11159
Quoting leftlink:
Here is a link about rescue teams running from the radiation as winds move onshore.



Wow. Can these people not catch a break?
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Quoting GeoffreyWPB:


We received a good dousing early this morning. I believe as time goes on, things will even out. They usually do.


Always the optimist. Can't you be an alarmist just once and say we are drying up and no water will be available and get a good argument doing. You always have to play the nice guy.
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Quoting jitterboy:



What does a neutral season typically mean in terms of # of storms?


Neutral years tend to yield an above-average number storms.
Member Since: October 28, 2006 Posts: 57 Comments: 30494
Quoting GeoffreyWPB:


As in Samuel Mudd?


He was cleared of all charges, (and so was I)
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Here is a link about rescue teams running from the radiation as winds move onshore.
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Quoting Drakoen:


That is a real possibility. A weak La-Nina. I looked at the CFS and GloSea model which takes us into neutral with a cool bias with the given rate of warming. An interesting thing to note is that the GloSea underestimated the rate of warming in its 3-month lead forecast. If we consider the Glosea to be an underestimation and the ECMWF members to be an overestimation then perhaps need to take the mean of the total ECMWF members and the Glosea members which I would see as a neutral with a slight warm biased which I think is what we will be looking at this hurricane season.

The March 2011 IRI ENSO forecast models have the average among the all dynamic models right around neutral, so this season could be absolutely neutral.




Nuetral could be rather bad as history shows. LaNina might come a little late for much protection this year for the ConUs
Member Since: September 2, 2007 Posts: 178 Comments: 20439
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Quoting TampaSpin:


Like heck, the boy is a legend. He has only had one life and is as old as mother earth!



True. Very true, Tampa. I stand corrected.

Hey, Grothar. What is with all the aliases?
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Quoting Drakoen:


That is a real possibility. A weak La-Nina. I looked at the CFS and GloSea model which takes us into neutral with a cool bias with the given rate of warming. An interesting thing to note is that the GloSea underestimated the rate of warming in its 3-month lead forecast. If we consider the Glosea to be an underestimation and the ECMWF members to be an overestimation then perhaps need to take the mean of the total ECMWF members and the Glosea members which I would see as a neutral with a slight warm biased which I think is what we will be looking at this hurricane season.

The March 2011 IRI ENSO forecast models have the average among the all dynamic models right around neutral, so this season could be absolutely neutral.




What does a neutral season typically mean in terms of # of storms?
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Quoting Some1Has2BtheRookie:


Tampa, those are not aliases. Those are former lives!


Like heck, the boy is a legend. He has only had one life and is as old as mother earth!
Member Since: September 2, 2007 Posts: 178 Comments: 20439
Quoting GeoffreyWPB:


As in Samuel Mudd?




No, just Mudd.
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Quoting Some1Has2BtheRookie:



Well, his new name will probably be spelled by all the same way. Mud. That one is hard to spell wrong. Still, we may see the occasional spelling as, Mudd. Sometimes, life does get simpler?


As in Samuel Mudd?
Member Since: September 10, 2007 Posts: 0 Comments: 11159
Quoting TampaSpin:



I have heard a couple of alias names on you too........LOL


Tampa, those are not aliases. Those are former lives!
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Quoting BahaHurican:
So suggesting no escape from la nina is likely???


That is a real possibility. A weak La-Nina. I looked at the CFS and GloSea model which takes us into neutral with a cool bias with the given rate of warming. An interesting thing to note is that the GloSea underestimated the rate of warming in its 3-month lead forecast. If we consider the Glosea to be an underestimation and the ECMWF members to be an overestimation then perhaps need to take the mean of the total ECMWF members and the Glosea members which I would see as a neutral with a slight warm biased which I think is what we will be looking at this hurricane season.

The March 2011 IRI ENSO forecast models have the average among the all dynamic models right around neutral, so this season could be absolutely neutral.

Member Since: October 28, 2006 Posts: 57 Comments: 30494
Quoting Grothar:
Gadhafi, Gaddafi, Qaddafi, Khadafy, or Khadafi?

If you use the Associated Press as your standard-bearer you should use the spelling Moammar Gadhafi.

The Washington Post is using Moammar Gaddafi as their preferred spelling.

The New York Times is using Muammar el-Qaddafi and even acknowledging his position in the military.

The Boston Globe is using Moammar Khadafy.

Agence France-Presse is using Moamer Khadafi when writing about the Libyan dictator.




I have heard a couple of alias names on you too........LOL
Member Since: September 2, 2007 Posts: 178 Comments: 20439
Quoting Grothar:


Geoff, don't know if you saw this earlier. Seems trivial compared to what is going on the world, but it is really getting serious by us. Looks like you neck of the woods is having the same thing.



We received a good dousing early this morning. I believe as time goes on, things will even out. They usually do.
Member Since: September 10, 2007 Posts: 0 Comments: 11159
Quoting Grothar:
Gadhafi, Gaddafi, Qaddafi, Khadafy, or Khadafi?

If you use the Associated Press as your standard-bearer you should use the spelling Moammar Gadhafi.

The Washington Post is using Moammar Gaddafi as their preferred spelling.

The New York Times is using Muammar el-Qaddafi and even acknowledging his position in the military.

The Boston Globe is using Moammar Khadafy.

Agence France-Presse is using Moamer Khadafi when writing about the Libyan dictator.




Well, his new name will probably be spelled by all the same way. Mud. That one is hard to spell wrong. Still, we may see the occasional spelling as, Mudd. Sometimes, life does get simpler?
Member Since: Posts: Comments:
Gadhafi, Gaddafi, Qaddafi, Khadafy, or Khadafi?

If you use the Associated Press as your standard-bearer you should use the spelling Moammar Gadhafi.

The Washington Post is using Moammar Gaddafi as their preferred spelling.

The New York Times is using Muammar el-Qaddafi and even acknowledging his position in the military.

The Boston Globe is using Moammar Khadafy.

Agence France-Presse is using Moamer Khadafi when writing about the Libyan dictator.

Member Since: Posts: Comments:
Quoting Grothar:


LOL! Gives a new meaning to the phrase "Three Sheets to the Wind, eh?


Yes. LOL. We also now know where the phrase "Watch you back" probably originated.
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Quoting GeoffreyWPB:
I think a lot of us are on sensory overload. With everything going on in the world, and the very slow drip, drip, drip of new updates, the talking heads are stretching for news to report. Glad I have a DVR.


Geoff, don't know if you saw this earlier. Seems trivial compared to what is going on the world, but it is really getting serious by us. Looks like you neck of the woods is having the same thing.

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Quoting Skyepony:
Euro~Thanks.. Some translation was lost in the cut & paste. Had to resort to Babelfish. Had I just walked away without checking it you would have subdued undue panic.


Grother~ Sometimes I'm just too impatient, or like the other day~ your not around. Don't know why but I can 1/2 read of several languages. Many times just enough to know it's something really pertains or good stuff.

Those animated plume tracker/models come from ZAMG. There's links embed if you click on the maps posted earlier. You could translate & post the other info they put out today about WMO Day. I think there is some ZAMG history in there too I'd like to see translated.


Just got back and saw this. A complete transaltion is on your WU mail on this article (without the mistakes from Google)
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Quoting Some1Has2BtheRookie:


I never said Brute was a friend. He said this to me in passing. He said he was in hurry to an important meeting. Who knew?


LOL! Gives a new meaning to the phrase "Three Sheets to the Wind, eh?
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Quoting Drakoen:
Simply to boast the ECMWF's seasonal forecast accuracy, lets look at the ECMWF 6-month lead forecast for the Nino 3.4 region from last August projected to February first. The blue line represents the observed conditions while red lines are the individual ensemble members. As you can see what was actually observed matched very closely to the mean of the ensembles members if we were to draw a trendline based on the individual members:




Now, I looked at the ECMWF seasonal forecast from the past 3 months up until now and it seems to be trying to warm things up a little faster than what we are observing so if we look at the latest ECMWF seasonal forecast and take the right hand side (cooler side) of the ensemble members and take the mean then that could very well be what we would be looking at for this upcoming hurricane season.

ECMWF latest seasonal prediction forecast for the Nino 3.4 region:
So suggesting no escape from la nina is likely???
Member Since: October 25, 2005 Posts: 19 Comments: 22140
Quoting Skyepony:



If you add your Personal Weather Station to the WeatherUndergound Network you get free website membership, free data hosting, great graphs of your data & I can show you the weather in my North Garden in a sylish little constantly updating sticker (or a number of variation of)..


WeatherUnderground~ Our weather stations are in your backyard...

That bestcast that's discussed in that article~ A forecast for your weather station (or that one right down the street), an awesome feature you can't get anywhere else~ had alot to do with the new site design. Well that & making it faster. Considering how much WU has changed over the years, I was surprised by some of the backlash. I think people didn't realize it had a set release day & their input has been used since (& this continues) to improve & finish it.
ONe of the things I noticed right away with the city pages is that local forecast. Considering that there's a lot less feedback from local sources here, the quality of the forecast is usually pretty darn good. I agree that the changes I've seen since 2005 have been almost completely for the better. One thing we don't give much credit for is the self-monitoring system WU uses in its blogs. I think it's better than what a lot of other sites use.
Member Since: October 25, 2005 Posts: 19 Comments: 22140

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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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