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thanks chio for the reply. From what i here solar activity is on the rise would that have any effect on the strat down the line? If i'm rite last dec's cold was scuppered by that according to gp. Shame wouldn't get his input this winter.

Is it really on the rise? from what I have seen it was in decline. The CM Predicts a rise while the SC predicts a drop but I don't think anyone can say for certain.http://sidc.oma.be/sunspot-index-graphics/wolfjmms.php

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Welcome Cirus and thanks - this thread is truly international!

 

I am happy to say that your English is a lot better than my French!

 

We may see that period of Vortex Intensification as the wave 1 activity seems to have reinforced the vortex rather than weaken it  - the end of the month forecast at 10 hPa shows the vortex to be strengthening as one would expect.

 

post-4523-0-34740100-1382471205_thumb.gi

 

 

 

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Thank you. I learned a lot here, so its only fair to try and give something back. Posted Image But of course I still have a huuuge amount to learn in the coming years, because this subject is way too big to handle it in one year. Posted Image

 

@Chio (or as I first called you, Mr. Chionomaniac Posted Image): The averaging does take away some possible correlation. I will have to wait until the tool can plot monthly subsets, before we can go deeper in the matter, with your recommended areas. I will try to do some subtractions of the polar vs. tropical temps, and then try and correlate that with the zonal mean zonal wind. 

 

About the ozone: I came across some O3 data during my short but rich reanalysis career. Posted Image

Total stratosphere ozone by ECMWF data. Recent years on the left, and zonal monthly mean on the right.

 

Posted Image Posted Image

 

For further in-depth analysis and year-to-year (even daily) comparisons, you can find the best O3 data on the web here: http://www.temis.nl/macc/index.php?link=o3_msr_daily.php Posted Image

 

Meanwhile, GFS and GEFS are slowly but steadily starting to agree. Posted Image

Posted Image Posted Image

 

 

Regards

That looks very much like a 'classic' SW'ly regime will dominate in Nov after the intiial thrust of busy activity.  That seems in line with solar factors

 

A very mild Nov seems in offing then

 

BFTP

Edited by BLAST FROM THE PAST
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That looks very much like a 'classic' SW'ly regime will dominate in Nov after the intiial thrust of busy activity.  That seems in line with solar factors

 

A very mild Nov seems in offing then

 

BFTP

What solar factors are they then.Talk about 1+1 making 4

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Hello everybody ! I'm new to this forum. It's the first time that I write on a foreign forum. I introduce myself briefly. I'm french and I'm 19 years old. I'm student in CPGE (Classes Préparatoires aux Grandes Ecoles). I take care to carry out or to achieve analysis on this website : http://www.espacemeteo.com/Prevision-Meteo/Analyse-stratospheriqueExcuse me, if my english grammar can be a little bad, or my vocabulary. I've read this topic, sometimes, each winter, since 2011. This thread is very interesting, to follow. I congratulate Chionomaniac, Recretos, and other people for their steady involvement on this topic :)The extended winter has started since mid-october. We could see a minor displacement event (very minor) in the middle stratosphere. The wave activity, near the stratopause (wave number 1), was born at an early stage for the extended winter. Furthermore, thanks to the wave activity in the troposphere, toward the lower stratosphere (at the end of September and at the beginning of the current month), it allowed to promote this stratospheric event, at 10 hpa.Currently, the extended range forecast abide a vexed question. We must wait the next month, in order to have a better idea on the likelyhood of CW (Canadian Warming), or on the risk of SVI (Stratospheric Vortex Intensification), which can provoke a recurrence of zonal regime above the atlantic ocean and the european continent, through a downwelling of NAM+ in the stratosphere.For the moment, the zonal regime seems to strenghten itself on numerical models.Best regards.

Welcome Cirus,look forward to your inputs.
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Welcome Cirus and thanks - this thread is truly international!

 

I am happy to say that your English is a lot better than my French!

 

We may see that period of Vortex Intensification as the wave 1 activity seems to have reinforced the vortex rather than weaken it  - the end of the month forecast at 10 hPa shows the vortex to be strengthening as one would expect.

 

Posted Imageecmwf10f240.gif

 

 

 

But, I can tell you that my accent is so frenchy, when I speak English lool ^^.

Yes, this thread is international. I know such french people (in another french forum) who come here in order to read such important analysis. But, they don't publish little posts, or replies, in this topic.

 

Yes, absolutely, zonal mean zonal wind will tend to increase sharply, more especially at the top of the stratosphere, due to the weakness of the wave 1 activity. Generally, after a minor displacement event, it is possible to have a single downward propagation of NAM- toward the lower stratoshere, and sometimes toward the troposphere. But those effects doesn’t persist over 2 weeks, as a small wave 1 component maintains the polar vortice (the planetary wave associated propagates only at the edge of the vortex). We can note that a period of vortex intensification appears thereafter, as you say, with a "tidal wave" of NAM+ in the stratosphere, up to the troposphere sometimes. If, the wave 1 component is really too weak, the NAM- values can be really negligible, insignificant in the stratosphere. Recent examples … minor displacement events of 6th January 2011 and 31th January 2011 (approximately).

 

Posted Image

Two years ago, I published a case study on such particular displacement event minor (the abstract is in english, but the rest is in french) and those effects in the troposphere.

The link is here

 

If you want to see the whole case study, sorry, it takes to create an account ^^

 

 

“Pour revenir à nos moutons†(It’s a french expression^^)

 

 In the mid-stratosphere, the polar vortice would be able to be like a bean or in comma shape (very very slightly nevertheless), at the end of this month. After that, indeed, the vortex will enhance with the emergence of wave 0 component, if I can say this.

 

 

 

 

Welcome Cirus,look forward to your inputs.

 

 

Thanks joggs Posted Image

Edited by Cirus
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Welcome Cirus and thanks - this thread is truly international!

 

I am happy to say that your English is a lot better than my French!

 

We may see that period of Vortex Intensification as the wave 1 activity seems to have reinforced the vortex rather than weaken it  - the end of the month forecast at 10 hPa shows the vortex to be strengthening as one would expect.

 

Posted Imageecmwf10f240.gif

How can wave1 reinforce vortex? i was under the impression it would help break it down. Also  I noticed warming at 1.Hpa. is that indicative of a Canadian SSW?

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How can wave1 reinforce vortex? i was under the impression it would help break it down. Also  I noticed warming at 1.Hpa. is that indicative of a Canadian SSW?

If you push your finger on a balloon and it doesn't pop and you take your finger off then the balloon will resume its former shape straight away. It appears that the vortex does this as well, but strengthens as well - especially in the cooling phase. Cirus has demonstrated this in his post above with the positive NAM response to the weak wave 1 activity. 

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If you push your finger on a balloon and it doesn't pop and you take your finger off then the balloon will resume its former shape straight away. It appears that the vortex does this as well, but strengthens as well - especially in the cooling phase. Cirus has demonstrated this in his post above with the positive NAM response to the weak wave 1 activity. 

Thanks. Great analogy. helps me understand better. And about the 1Hpa warming is anything to watch? looks to be downwelling at a decent rate. but i assume this is fairly normal this time of year. 

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If you push your finger on a balloon and it doesn't pop and you take your finger off then the balloon will resume its former shape straight away. It appears that the vortex does this as well, but strengthens as well - especially in the cooling phase. Cirus has demonstrated this in his post above with the positive NAM response to the weak wave 1 activity. 

 

Besides what chio said here structurally, you also have the issue of advection and location. At this early stage, the vortex being pushed slightly closer to Siberia will cause even more irreversible heat transfer, as parcels radiatively cool more than if it was just climo. In fact, notice in the upper stratosphere the "warmer" temperatures over Europe currently become abruptly cold as they move over Siberia in 3+ days. This is exactly the process described.

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Little something we should keep an eye on.

 

T192

 

Posted Image

 

T384

 

Posted Image

 

Distant but I remember someone saying last year that it doesn't vary that much in long range its either there or not.

Edited by SN0WM4N
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http://www.americanwx.com/bb/index.php/topic/41498-possible-early-detection-for-ssw-event-underway/

Our American collegues are interested in SSWs & stratosphere as well. Please take a look over here. I made a 'picture' of the first entry of this topic, because you have to login to see the attachments. I'm curious about your (whoever wants to respond) interpretation of this analysis.

 

 

post-10577-0-29310000-1382601358_thumb.p

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This coukd prove to be an interesting winter. With such exstensive snow and ice so early in the season, it will be interesting to see what happens across Europe if the PV does indeed strengthen to such an extent that we need a SSW event to break it down and release the cold.

Will the huge expansion of snow and ice so early have an effect in helping to generate a SSW....?

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http://www.americanwx.com/bb/index.php/topic/41498-possible-early-detection-for-ssw-event-underway/

Our American collegues are interested in SSWs & stratosphere as well. Please take a look over here. I made a 'picture' of the first entry of this topic, because you have to login to see the attachments. I'm curious about your (whoever wants to respond) interpretation of this analysis.

 I think that it is too soon for a Canadian warming and certainly for a SSW - the posts above from anthonym and myself were in response to this possibility. If you look at the 1hPa zonal mean wind forecasts for day 10 then you can see that the forecasts are suggesting that we will reach over 50m/s at 60N - that is getting nearer the 80m/s that we will see at max vortex conditions in the heart of winter - so certainly no negative effect there.

 

There is a negative mean zonal wind anomaly created by this wave 1 activity and what will be interesting will be to seee if this propagates down the stratosphere towards the trop like 2009.

 

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_UGRD_ANOM_ALL_NH_2009.gif

 

If so then we could see a tropospheric affect towards the end of November - perhaps coinciding with a poleward pulse of positive AAM, before the positive mean zonal winds re emerge in December. Now that really is conjecture!

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What solar factors are they then.Talk about 1+1 making 4

The same ones that suggested this storm coming on time and on track well before the models were within range.  We'll see how November pans out......1+1 = mild and SW'ly after stormy start.  I think the strat will support this idea, the excellent posts on this thread seem to suggest this to me.

 

BFTP

Edited by BLAST FROM THE PAST
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The same ones that suggested this storm coming on time and on track well before the models were within range.  We'll see how November pans out......1+1 = mild and SW'ly after stormy start.  I think the strat will support this idea, the excellent posts on this thread seem to suggest this to me.

 

BFTP

Aye, but what are they? 'On track' according to what?

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 I think that it is too soon for a Canadian warming and certainly for a SSW - the posts above from anthonym and myself were in response to this possibility. If you look at the 1hPa zonal mean wind forecasts for day 10 then you can see that the forecasts are suggesting that we will reach over 50m/s at 60N - that is getting nearer the 80m/s that we will see at max vortex conditions in the heart of winter - so certainly no negative effect there.

 

There is a negative mean zonal wind anomaly created by this wave 1 activity and what will be interesting will be to seee if this propagates down the stratosphere towards the trop like 2009.

 

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_UGRD_ANOM_ALL_NH_2009.gif

 

If so then we could see a tropospheric affect towards the end of November - perhaps coinciding with a poleward pulse of positive AAM, before the positive mean zonal winds re emerge in December. Now that really is conjecture!

 

The thing to remember about 2009 is there was also a minor-warming in December so how much the trop was affected in the early winter by this or the preceding wave 1 is hard to say.

A good year to compare for early wave 1 activity is 1996 where it was strong enough to give a displacement SSW in November.

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with regards to the posts on solar activity I have a thought and it may be wrong and idiotic but always been told if u don't ask u will never know.

 

I took this line from a post in the American forum that was linked above

 

(We've also seen the PV take shape more often than not on the other side of the globe in recent years. Not exactly sure why other than perhaps luck, but Europe has had some brutal winters.)

 

now I have only been keeping an eye on the models and such for the last couple of years but one thing I have noticed is that during periods where the solar activity picks up then that's when the PV tends to go more towards Greenland area and give us a more zonal picture like 2011/12 and during early parts of last winter and also just now.

 

now I know these may just be coincidence but it is uncanny how it happens.

 

now when we look at other periods of low solar activity like we are in now Europe seems to be the place that benefits the most through these periods in the context of colder winters.

 

my question is can the low solar activity periods simply affect what position in the northern hemisphere the PV calls home.

 

like if the PV takes long periods during solar lows of being sat over Siberia direction instead of more toward Greenland then surely this would open up our side of the hemisphere to greater chances of northern blocking with the PV being toward Siberia and in turn would help us with the colder winters we see during these periods as with the PV being sat more towards Siberia it gives us a better chance of tapping into the real deep cold air than if it was to be more toward the canadian side of the hemisphere.

 

sorry if I shouldn't be posting this in this thread but I was just going off the comments made above.

Edited by Buriedundersnow
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