Stratosphere Temperature Watch 2013/2014

[Snowy L]

Solar max is a somewhat nebulous arithmetic concept anyway: where's the max here?

 

 

Rest assured we are in the current year(s) of peak activity. The poles have flipped recently as we can see here:

 

 

I'm pretty dubious about solar-climate connections to be honest, especially at the short range.

 

 

I think it's safe to say that we are past solar maximum now. Also the solar maximum was a very low one. The correlation between solar cycle/QBO/SSWs is more based on actual solar flux 10.7 cm rather than solar maximum/minimum. So even though we are close to a solar maximum, the actual solar flux is low as this has been a very weak solar maximum. I wasn't a great supporter of solar-climate links either, but the soalr cycle/qbo links have shown some good correlations in experiments, particularly solar max/qbo west links.

 

http://strat-www.met.fu-berlin.de/labitzke/moreqbo/MZ-Labitzke-et-al-2006.pdf

 

Page 8 shows the graphs and it shows a decent positive correlation between West QBO, Solar flux and SSWs, though the correlation is weaker when it comes to East QBO and solar flux.

 

Edit: Forgot that they're measuring 30hpa Geopotential height at the North Pole, not SSWs. But greater heights at the North Pole implies displaced/split/weakened vortex.

Edited October 15, 2013 by Snowy L

[BLAST FROM THE PAST]

A great new topic, and so much material to work with. And the awesome intro post by chionomaniac. 

 

 

That composite speaks for itself, but you have to keep in mind that there is much more to those years than just the low sea ice, like the oceans. So if I could rephrase that sentence, I would say "The current AMO/PDO combination 500 hpa anomaly give us a massive tropospheric headstart".  Of course among many other things, but keeping the main players in mind. Also realizing that the PDO and AMO are the "gatekeepers" to the Arctic. Too bad the sea ice data goes only back to 1980, because it would be interesting to see a correlation of these two cycles and the sea ice, for at least 100 years back.

 

For example: Comparison of the last 3 great ocean cycle swings. 

50-75= Cold PDO / Warm AMO

80-98= Warm PDO / Cold AMO

99-12= Cold PDO / Warm AMO (as 50-75)

 

That would be all for now.

 

Best regards.

 

That fits very snugly with the link I have suggested that a -ve NAO is highly 'encouraged' by the -ve PDO and current solar driven perturbation cycle.  The composites are quite stark.  We have added whammy of a very low solar cycle possibly heading towards a deep minima a la Dalton or Maunder. 

Anyway, its the strat thread....but I think they are intrinsically linked

 

BFTP

[Buriedundersnow]

would this be more wave activity forecast by the GFS 18z and I know its way out in FI but the wave activity we are seeing just now had some signs showing in FI on the GFS.

 

[summer blizzard]

That fits very snugly with the link I have suggested that a -ve NAO is highly 'encouraged' by the -ve PDO and current solar driven perturbation cycle.  The composites are quite stark.  We have added whammy of a very low solar cycle possibly heading towards a deep minima a la Dalton or Maunder. 

Anyway, its the strat thread....but I think they are intrinsically linked

 

BFTP

 

I did see data on another forum a while ago which evidenced a good positive correlation between the winter PDO and AO on a decadal timescale (ergo a -PDO decade is typically also a -AO decade).

[Harve]

would this be more wave activity forecast by the GFS 18z and I know its way out in FI but the wave activity we are seeing just now had some signs showing in FI on the GFS.

 

gfsnh-10-384.pngnpst30.pngnpst30CATQ0ZAA.png

When it's below the latitude of the UK, definitely not anything of the sort we tend to look for. Edited October 16, 2013 by Harve

[chionomaniac]

For those who spend a lot of time looking at the CFSv2 monthly forecast charts it is worth reading the following abstract. Effectively, I read that as suggesting that the predicted AO winter values are underestimating the contribution of the stratospheric feedback from October Eurasion snow gain. If anyone has a spare £30 then they can get the whole paper!

 

Abstract

Lagged ensembles from the operational Climate Forecast System version 2 (CFSv2) seasonal hindcast dataset are used to assess skill in forecasting interannual variability of the December–February Arctic Oscillation (AO). We find that a small but statistically significant portion of the interannual variance (>20 %) of the wintertime AO can be predicted at leads up to 2 months using lagged ensemble averages. As far as we are aware, this is the first study to demonstrate that an operational model has discernible skill in predicting AO variability on seasonal timescales. We find that the CFS forecast skill is slightly higher when a weighted ensemble is used that rewards forecast runs with the most accurate representations of October Eurasian snow cover extent (SCE), hinting that a stratospheric pathway linking October Eurasian SCE with the AO may be responsible for the model skill. However, further analysis reveals that the CFS is unable to capture many important aspects of this stratospheric mechanism. Model deficiencies identified include: (1) the CFS significantly underestimates the observed variance in October Eurasian SCE, (2) the CFS fails to translate surface pressure anomalies associated with SCE anomalies into vertically propagating waves, and (3) stratospheric AO patterns in the CFS fail to propagate downward through the tropopause to the surface. Thus, alternate boundary forcings are likely contributing to model skill. Improving model deficiencies identified in this study may lead to even more skillful predictions of wintertime AO variability in future versions of the CFS.

 

http://link.springer.com/article/10.1007%2Fs00382-013-1850-5

 

 

 

Also one of the SSW's that interest me this winter is the one from 2009. If we recap then this occurred early Feb 2009 in a west QBO during solar MINIMUM - previously unheard of. This occurred during the first strat temp watch thread and I remember our surprise at this event at the time. There is another comparitive study that showed that the pre-SSW period in 2009 was characterized by a peak in the 100 hPa eddy heat flux with a predominance of wave number 2 activity. This was due to strong anomalies associated with Rossby wave packets originating from a deep ridge over the eastern Pacific.

 

http://onlinelibrary.wiley.com/doi/10.1029/2010JD015023/abstract

 

 

So that is what we will need to look out for and monitor this winter - the 100hPa heat flux - especially in January. As soon as the US govt sites are back then I will go straight to the composites to look at analogue years for that and East Pacific Ridges in January. In fact I have aleady looked up H500 anomaly for January analogue years and guess what? Yes - big signal for that East Pacific ridge. More credence to that split SSW early Feb theory?

 

 

 

[MattH]

Morning, just a quick post seeing Ed has brought up the CFSv2, but the following links may well be of worth. Apologies but not sure how to actually make the images appear so they can be referenced back to within the thread, but the second and third links in particular I have found very interesting in terms of keeping an eye on as all of these are based on the CFSv2;

 

http://www.atmos.albany.edu/student/macritch/realtimemjo.png

http://www.atmos.albany.edu/student/macritch/naoindex.png

http://www.atmos.albany.edu/student/macritch/aoindex.png

 

Also some of you may or may not have seen this website, but it has a lot of support within the scientific community in terms of the work that Paul Roundy has done over at Albany Uni, could well be a few links in there that may be of interesting to some, so take a look and please highlight/comment accordingly - http://www.atmos.albany.edu/facstaff/roundy/waves/

 

Finally, I quickly mentioned on twitter yesterday but the October update of the EC seasonal and EUROSIP which for the record combines the EC Seasonal, UKMO, NCEP and MeteoFrance long range models, both signal a generally higher than average pressure anom to the N through D/J/F. The EC seasonal is more noteworthy and has a marked 500hpa anom to the N of the UK, as a mean over the three months. The EUROSIP has a weaker signal and this displaced to the NW near Iceland/Greenland with lower pressure just to the S or SE. Neither models do or have for the last few months at least signaled any sort of winter period that looks set to be dominated by a persistent zonal and general +NAO pattern.

 

Regards to all,

 

Matt.

[Geoff Sharp]

I have also been watching the NH polar vortex and jet streams for the past 4 winters. I am involved in solar research and have an interest in weather effects from a quiet Sun. The jet stream looks to be affected by changes in the ozone quantites in the top of the stratosphere where above 45km the quanity is increasing during this what could be a grand solar minimum.

 

I also think a shrinking thermosphere is somehow related to the changes we are seeing with low pressure systems world wide, the jet stream is meridional no matter what phase the AO is in it seems. The more abundant low pressure systems doing their thing. I am predicting the harshest winter this year to be in Russia and central Europe because of the QBO westerly phase.

 

I have predicted the coming NH winter at the end of July for the last 4 years, the following link shows this coming winter along with links to past predictions.

 

http://www.landscheidt.info/?q=node/311

 

The Sun and net weather effects are "under new management" during what will be known as the Landscheidt Minimum. The new paradigm should last 30 years and have nothing to do with so called global warming.

 

ps...my research is very different to Landscheidts.

[FrenchScotPilot1]

I haven't had much time yet but I now take this opportunity to repeat what has already been said: thanks very much Ed and other contributors to make this thread, abeit quite technical, VERY VERY interesting and informative!!

It really furthers our knowledge of atmospheric physics every time.

Best regards,

Stephane

[jonboy]

I have also been watching the NH polar vortex and jet streams for the past 4 winters. I am involved in solar research and have an interest in weather effects from a quiet Sun. The jet stream looks to be affected by changes in the ozone quantites in the top of the stratosphere where above 45km the quanity is increasing during this what could be a grand solar minimum.

 

I also think a shrinking thermosphere is somehow related to the changes we are seeing with low pressure systems world wide, the jet stream is meridional no matter what phase the AO is in it seems. The more abundant low pressure systems doing their thing. I am predicting the harshest winter this year to be in Russia and central Europe because of the QBO westerly phase.

 

I have predicted the coming NH winter at the end of July for the last 4 years, the following link shows this coming winter along with links to past predictions.

 

http://www.landscheidt.info/?q=node/311

 

The Sun and net weather effects are "under new management" during what will be known as the Landscheidt Minimum. The new paradigm should last 30 years and have nothing to do with so called global warming.

 

ps...my research is very different to Landscheidts.

 

Welcome Geoff yo Netweather. I always have a look at your website before coming here and your paper on the uranus/neptune effect adds to this whole debate keep up the great work

Jon

[chionomaniac]

Thanks for those links Matt - will bookmark. And welcome to Netweather Geoff.

[sebastiaan1973]

Also one of the SSW's that interest me this winter is the one from 2009. If we recap then this occurred early Feb 2009 in a west QBO during solar MINIMUM - previously unheard of. This occurred during the first strat temp watch thread and I remember our surprise at this event at the time. There is another comparitive study that showed that the pre-SSW period in 2009 was characterized by a peak in the 100 hPa eddy heat flux with a predominance of wave number 2 activity. This was due to strong anomalies associated with Rossby wave packets originating from a deep ridge over the eastern Pacific.

 

http://onlinelibrary.wiley.com/doi/10.1029/2010JD015023/abstract

 

 

So that is what we will need to look out for and monitor this winter - the 100hPa heat flux - especially in January. As soon as the US govt sites are back then I will go straight to the composites to look at analogue years for that and East Pacific Ridges in January. In fact I have aleady looked up H500 anomaly for January analogue years and guess what? Yes - big signal for that East Pacific ridge. More credence to that split SSW early Feb theory?

 

 

 

If I'm correct, that SSW had trouble with downwelling due to the westerly QBO (?), so the effects on 'our' weather were limited.

[Recretos]

If I'm correct, that SSW had trouble with downwelling due to the westerly QBO (?), so the effects on 'our' weather were limited.

 

The 2009 SSW was a nice "downweller" actually.

 

 

Thanks Matt for the links. Some nice content there, which is somewhat more "pro" oriented, but I am sure that we amateurs can also make the best use of it.

 

I am late for work, so just some quick correlations between Oct-Nov QBO and the stratosphere. I caught the brief window when the NCEP reanalysis sites were available (offline atm.) and decided to make some correlations for use/comparison in the near future.

A quite high positive correlation between the 10mb temp. and the QBO. In this particular case, it shows where the temperature changes/increases in a west (positive) QBO (positive correlation). Nothing new really, because of the known relationship between the QBO and BDC.

 

 

 

Geopotential height. Some more pressure form the Pacific area is evident on the correlation, as well as on the forecast. But we have to keep in mind that the QBO-Stratosphere relation is also affected by the Solar activity. So the problem with these correlations is that it has all the years with low and high activity. I am sure I could get even better correlations when filtering the years, but that is impossible with these basic reanalysis tools. 

 

 

Now, a somewhat more interesting (but expected) correlation between the PNA and Z30mb. The correlation is not all that high, but when considering the year range and the fact that all years are included, it is quite decent. Added is the latest GEFS PNA forecast. 

 

 

 

I will end with the "experiment" correlation of Oct-Nov solar flux, and Jan-Feb 10mb temperature. The 4 month lag did gave a slightly better correlation than no lag or lower lag. It is evident that the increased Oct-Nov solar flux does tend (emphasis on the tend) to promote SSW in general, with leaning more towards splits. But this correlation is generalised and unfiltered. It would require QBO filtering. I will contact NCEP and ask them about the possibility of filtering. 

 

 

Too bad I dont have the time for a longer post, but I was trying to make these correlations for some time now, but of course that wasn't possible due to the gov. shut-down. Luckily the sites are now available again and I have some more correlations in plan for the near future. 

 

p.s.: In case some of you are unfamiliar with the concept of correlations, or you dont know how to interpret these graphics, please tell me, and I will write a simple guide how to interpret these correlations.

Best regards.

[Geoff Sharp]

Thanks for the welcome, my interests in the jet stream will compound further as our local Australian media and opposition parties are going mad on the extreme weather events that have encouraged severe bush fire events. The persistant low pressure systems are dragging warm air from the interior associated with strong winds that provide great conditions for wild fires. This will be a weather pattern that will last 30 years, fun times ahead.

 

Down in the Southern Hemisphere we have seen a fairly strong negative AAO with our southern vortex being broken up with Antarctic high pressures and temps. The jet stream has moved away from the south pole and is affecting the mainland of Australia. Down here we are not supposed to be affected by planetary waves so the breakup of the southern vortex is perhaps more of a mystery.

Edited October 18, 2013 by Geoff Sharp

[MattH]

Just a quick one, but interesting Asian mountain torque event evident at the moment;

 

http://www.esrl.noaa.gov/psd/map/images/reanalysis/aam_total/gltaum.90day.gif

 

Reasonable region of ozone build up as well in relation to that region of warmth that has been highlighted;

 

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/gif_files/gfs_toz_nh_f48.gif

http://users.met.fu-berlin.de/~Aktuell/strat-www/wdiag/figs/ecmwf1/ecmwf30f48.gif

 

EC does remove it with time and the vortex becomes increasingly potent at the upper levels. Be interesting to see if it has any possible influences within the early stages of the season mind, as at 30hPa at least temps have been 'stumbling' somewhat - http://ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/html_e/pole30_n.html

 

Interesting to note the EC32 shows a gradual progression away from the particularly cyclonic S or SW'ly regime the deeper we progress into November with a possible cooler/colder anticyclonic spell towards mid-month. Perhaps the above is having some influence(?)

 

Interesting start to the season in a way.

 

Cheers, Matt.

[Weather-history]

I have asked this question before or something similar to it but say we are in a blocked pattern and it's providing a really wintry spell, would you want a SSW to happen as it could potentially disrupt the blocked pattern?

[mountain shadow]

I wouldn't have thought so WH.

 

If we were in a blocked winter pattern, the high likliehood is that a SSW would aid the continuance of the blocking rather than hinder it.

 

Indeed, if were all ready in a blocked winter pattern caused by forcing other than a SSW, a SSW would be the winter icing on a cake.

[chionomaniac]

I have asked this question before or something similar to it but say we are in a blocked pattern and it's providing a really wintry spell, would you want a SSW to happen as it could potentially disrupt the blocked pattern?

My answer would always be yes. Firstly, a blocked pattern is more likely to lead to a SSW - it's all part of the troposphreric/ stratospheric feedback mechanism and any SSW is likely to prolong a blocked pattern, not shorten it imo.

 

Just as MS has said above!!

Edited October 18, 2013 by chionomaniac

[FrenchScotPilot1]

Does it not depend on where the fragmenting vortex goes and how it intereacts with the blocking high?

Is it fair to assume that it will always strengthen the block?

 

EDIT: Disregard. Chiono answered as I was typing.

Edited October 18, 2013 by FrenchScotPilot1

[FrenchScotPilot1]

I'm after an explanation about the link between Mountain Torque (there's one in Asia just now, so it is topical) and SSWs.

What is the physics behind it, what happens during the event?

Many thanks!

[UV-RAY]

My answer would always be yes. Firstly, a blocked pattern is more likely to lead to a SSW - it's all part of the troposphreric/ stratospheric feedback mechanism and any SSW is likely to prolong a blocked pattern, not shorten it imo.

 

Just as MS has said above!!

 

 

My answer would always be yes. Firstly, a blocked pattern is more likely to lead to a SSW - it's all part of the troposphreric/ stratospheric feedback mechanism and any SSW is likely to prolong a blocked pattern, not shorten it imo.

 

Just as MS has said above!!

It seems a bit like the chicken or egg scenario that one Chion?

 

I hope you don't think I'm a bit of a Stratophobe by the way.

Edited October 18, 2013 by Sceptical Inquirer

[Recretos]

It seems a bit like the chicken or egg scenario that one Chion?

 

Not at all. I would go as far to say that some ridging/blocking conditions are of great importance in the first place. Just like chiono said, its all a part of the troposphere/stratosphere coupling. And as is also evident on the composite for the weak polar vortex. And just for consideration: Split SSW: If you have a split vortex from the Pacific and the Atlantic, I don't think we will have to think twice where the split is "likely" to connect, or what would happen to the connecting ridge. A huge generalisation, with exceptions to every rule, but I hope the point I am trying to make here is obvious.

 

As Matt has pointed out, a decent mountain torque event is in progress in E. Asia, starting around 14th, with the increasing pressure gradients, and currently peaking.

   

 

 

The 10mb and 30mb temperature graphs look intriguing, with a temporary hold of the cool-down. I have plotted the 30mb and 10mb GFS forecasts, with 30mb on the downward trend, while 10mb kinda holds.

 

 

Best regards.

[Weather-history]

My answer would always be yes. Firstly, a blocked pattern is more likely to lead to a SSW - it's all part of the troposphreric/ stratospheric feedback mechanism and any SSW is likely to prolong a blocked pattern, not shorten it imo. Just as MS has said above!!

Thanks for your answer.I'm thinking what happened 1976-77 when the first half of winter was really cold, there was a SSW during the January and the rest of winter was mild.

[UV-RAY]

Not at all. I would go as far to say that some ridging/blocking conditions are of great importance in the first place. Just like chiono said, its all a part of the troposphere/stratosphere coupling. And as is also evident on the composite for the weak polar vortex. And just for consideration: Split SSW: If you have a split vortex from the Pacific and the Atlantic, I don't think we will have to think twice where the split is "likely" to connect, or what would happen to the connecting ridge. A huge generalisation, with exceptions to every rule, but I hope the point I am trying to make here is obvious.

 

As Matt has pointed out, a decent mountain torque event is in progress in E. Asia, starting around 14th, with the increasing pressure gradients, and currently peaking.

 

 

 

The 10mb and 30mb temperature graphs look intriguing, with a temporary hold of the cool-down. I have plotted the 30mb and 10mb GFS forecasts, with 30mb on the downward trend, while 10mb kinda holds.

 

 

Best regards.

Excellent stuff Recretos thank you.

[chionomaniac]

I often find it difficult to describe the coupling of the stratosphere with the troposphere, however I am going to try an analogy. For those who watch Come Dancing, then perhaps this will be easier to understand. 

 

The stratosphere/troposphere couple during winter are like a pair of dancers. However, this is no couple where one dancer takes the dominant lead - rather, we see a swapping of leads between the troposphere and the stratosphere during the dance. Occasionally, one will leave the other ( for instance a non propagating SSW) only to join up later. Generally, where one places their foot the other moves their own accordingly, so that the flow of the dance is kept and a symmetry is maintained. On other occasions one dancer (the stratosphere) can become the lead dancer and firmly clasps the other dancer (when it becomes very cold and increased in strength - vortex intensification) and that dancer (the troposphere) can not let go until the other dancer relaxes their grip (giving stratospheric led positive AO conditions). That grip can be relaxed instantly though by the other dancer tripping the lead dancer up ( through a SSW that will be tropospherically led by MT wave breaking) and the speed of the dance reduces or stops dramatically.

 

The fact though, is that during winter those two dancers are dynamically linked and anyone who looks at one without looking at the other will be judging the dance falsely or blindly - it would be akin to judging Torvill and not Dean or Dean and not Torvill, when in fact they were both dancing together all of the time!