Stratosphere Temperature Watch 2014/2015

[snowking]

The current forecast warming at the end of GFS FI exhibiting some similarities with that of 2012/13 as far as the 10mb temperature element goes:

 

Current Forecast:

 

Actual warming:

 

If we look at the forecast for the period running up to the 2012/13 warming, here was a typical example of the charts which first started taking our attention:

 

 

Of course we do not always see these warmings work their way all the way from FI to T+0, and indeed even during those weeks we saw plenty of waxing/waning of the forecast warming, so I am hoping this can act as a little bit of a warning to anyone hellbent on taking the rollercoaster ride of emotions (could read: tantrums) from the MOD over in to this thread - we will see significant inter-run variation of these forecast warmings, especially in terms of temperature profile. So prepare to see that and please try to avoid the knee-jerk reactions which would otherwise interrupt what is a thoroughly fascinating thread.

 

Everyone got that? Great, I can stop being such a grumpy so and so now

 

Also to say Andrej - the 3D cross-sections of the vortex are nothing short of stunning, and I hope we get to see more of these as the more interesting stratospheric setups start to appear.

 

All in all the pieces are slowly falling in to place at the very edge of the reliable timeframe. Let's hope to see a few ensemble means backing this trend as the week goes on.

 

SK

Edited December 7, 2014 by snowking

[chionomaniac]

Hi Chiono, is there an archive of these completed annual Berlin plots? Interesting on the 12/13, at the top of the Strat, u winds increasing prior to the sharp decrease and eventual reversal. We could be seeing similar starting to occur here, especially if that warming ramps up and comes to fruition in a couple of weeks.

 

Hi s4 - I meant to answer this earlier but didn't have time to do so. There is no Berlin historical data website that I can find. I have kept some but did lose earlier years due to previous computer crashes..

 

One can always get an idea of the previous years from this site:

 

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

 

or the Merra datasets

 

http://acdb-ext.gsfc.nasa.gov/Data_services/met/ann_data.html

 

 

 

 

BA I did look into this some time ago sadly though the research link met a bitter end as my last laptop imploded and with it the saved research. But from what I can remember is that the downwelling response is greater depending on the state of the AO at the time. In nutshell there was a greater response when the SSW took place ahead of a positive AO, the response became more muted as you went towards a negative AO.

 

I think this sort of makes sense as I'd view it as more explosive when in the positive AO phase as the pressure that's built up is likely to cause a bigger explosion post SSW, if you know what I mean!

 

I now consider it all interlinked. The stronger the strat PV, the stronger any trop jet will be, and that when conditions are right, a stronger wave deflection into the strat occurs as a result. Rather like a long jumper - he will jump a lot further if his run is faster than just a standing jump alone - the wave break into the strat can be considered similar.

[Cloud 10]

Zonal winds at the top really cranking up in the next few days with around 80 m/s on the cards.

 

 

 

As seen in previous years though,these can plummet rapidly.

 

2011/12..  2012/13...

[skatefan]

Hi s4 - I meant to answer this earlier but didn't have time to do so. There is no Berlin historical data website that I can find. I have kept some but did lose earlier years due to previous computer crashes..

 

One can always get an idea of the previous years from this site:

 

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

 

or the Merra datasets

 

http://acdb-ext.gsfc.nasa.gov/Data_services/met/ann_data.html

 

 

 

 

 

I now consider it all interlinked. The stronger the strat PV, the stronger any trop jet will be, and that when conditions are right, a stronger wave deflection into the strat occurs as a result. Rather like a long jumper - he will jump a lot further if his run is faster than just a standing jump alone - the wave break into the strat can be considered similar.

 

Yes, Is it correct to state that It requires more energy to disturb a strong vortex but when it happens the effects will be more spectacular? And: a weakened vortex is easier to disturb but the effects are less? There is a lot in between these....

 

On the other hand: a strong trop-jet (caused by a strong start PV) creates more energy and chances for MT's and warming are bigger.

 

Its all a matter of balance but Ideally it would be a weakened strat PV and relative strong trop-jet?

[Recretos]

GEFS looking good. 

 

 

 

And the warming in 3D. Or more like the warming "core", set at -45°C.  From 100mb to 1mb, from the 384h GFS 00z.

 

 

Edited December 8, 2014 by Recretos

[Snowy L]

My thoughts aswell nick. The careful side of me would prefer the -AO scenario as I expect any SSW would reinforce and deepen the existing pattern. The 'explosive' scenario would be fun but knowing our luck, a chunk of the Pv would end up in the Greenland/e Canada region as happened a few years ago and we would retain a +NAO keeping nw Europe on the 'warm side'.

 

When did this happen? The only time I remember this happening was in 2012/13 in January and we still got a good cold spell. If anything the mix of scandi high + Greenland vortex gave us more snow as massive lows collided with the cold air.

[bluearmy]

When did this happen? The only time I remember this happening was in 2012/13 in January and we still got a good cold spell. If anything the mix of scandi high + Greenland vortex gave us more snow as massive lows collided with the cold air.

 

cant recall snowy - i think there was a quick trop response which delivered a snowfall but all the subsequent downwelling responses failed to deliver for nw europe due to that east canadian chunk.

 

to the here and now - the zonal flow does seem to strengthen dramatically but perspective may be a bit lacking due to the poor effort made thus far this season. i have in my mind that a zonal flow of 30m/s @ 30 hpa is reflective of a strong upper vortex. over the next 10 days, ecm only manages that for a couple of them.

 

wont be long before we should find out how the gfs fi warming will imapct ecm output and given ian's post on the banter thread re Glosea's view of strat developments later this month, we may well be on the way.

 

anyone care to have a go at musing at what is the catalyst for this sudden warming up top. if its trop led, we should be seeing it verify shortly on the charts as its consistency means it must be happening within a week of the initial showing on T384 strat charts.

[sebastiaan1973]

I think you mean 2009?

[tcc]

I think you mean 2009?

That's what I was going to say! I distinctly remember Ed having to explain that the Feb 09 spell was due to the response, however some people weren't having it!

[MPG]

The whole SSW has been put on hold....................................Recretos has a tooth ache https://twitter.com/Recretos

[Ffive]

Its clear from what I read on here that there is a lot of knowledge and learning contained in these threads.

I did mention briefly in my post of Nov 30th (page 29) that the Major SSW of 1962/63 is probably a bench-mark.

 

The MAJOR STRATOPHERIC WARMING of (JANUARY)feb 1963 is worth studying in detail,as the Mid winter warmings of 1957 1958 were strikingly similar.

 

The initial warming started at 10mb level in mid-January and turned out to be,almost, (THE PERFECT STORM).....TO COIN A PHRASE. for us in the UK.

I,m sure your ALL familiar with the (dynamics)of planetary wave-zonal flow coupling, through eddy heat transport.

The reason I think the UK in that winter, was perfectly placed to benefit from the MAJOR ssw was that at the time there was a large-scale

(quasi-stationary wave set-up.....zonal harmonics....1 and 2.There was a rapidly building Atlantic Anticyclone,and a more diffuse Anticyclonic

system stretching across Asia,from the western Pacific Ocean.Over simplifying things....as there were other factors as well,Oscilations in planetary

waves and the mean (zonal wind) strength seem to correlate well.(strong planetary wave-zonal coupling).

Seems to me that,free planetary wave (MJO) moving wesward(16 day period)PHASED WITH STATIONARY WAVE,greatly enhanced the wave amplitude,and

northward transport of heat.This is one of the reasons for the "explosive warming"that took place in the mid-stratophere from mid-late Jauary.

Iteresting to note some the parallels in the mid-winter warmings of both 1957 and 1963.

(a) the large temperature rises initially appeared during the middle of January over southeastern Canada within the Southerly flow of a deep

North American Polar Trough and intensifying Atlantic anticyclone.

 

(b)The warm air thereafter spread generally Northwest in a direction nearly perpendicular to strong southwesterly jetstream.

 

© At the peak of the warming phase,temperatures at the 10-mb level near the warm center reached maximum values of about 0C.

 

(D) A MAJOR FEATURE.....of the circulation break-down,was the plunge of a cut-off low and cold center southward across North America

    at the same time warmer air overspread the polar region.

 

f5

[karyo]

Quite a notable downgrade today re: the warming in FI. It is particularly evident at the 30hpa level where the oranges have disappeared completely. There can of course be a variation in the intensity of the warming from run to run which we have seen on recent days but today we had 4 consecutive runs that have downgraded the warming.

 

Let's hope for a better day tomorrow.

 

Karyo

[Banbury]

Quite a notable downgrade today re: the warming in FI. It is particularly evident at the 30hpa level where the oranges have disappeared completely. There can of course be a variation in the intensity of the warming from run to run which we have seen on recent days but today we had 4 consecutive runs that have downgraded the warming.

 

Let's hope for a better day tomorrow.

 

Karyo

Again very difficult to access charts from I phone, any chance of posting the charts for the less fortunate to view.

 

Ta

[feb1991blizzard]

Warming coming into a nearer timeframe at the top though, propagation will take its time, its not going to be an instant response, remember, the lower down, the more variability from run to run will occur.

 

http://www.instantweathermaps.com/GFS-php/showmap-strat.php?run=2014120818&var=TMP&lev=1mb&hour=384

 

 

Edited December 9, 2014 by feb1991blizzard

[karyo]

Warming coming into a nearer timeframe at the top though, propagation will take its time, its not going to be an instant response, remember, the lower down, the more variability from run to run will occur.

 

http://www.instantweathermaps.com/GFS-php/showmap-strat.php?run=2014120818&var=TMP&lev=1mb&hour=384

 

 

I am also talking about the 30hpa level, not further down.

[feb1991blizzard]

I am also talking about the 30hpa level, not further down.

 

I know, im just saying that you cant always expect the 30mb chart to be as progressive as right up top, it may take a little while to propagate, I can see the concerns but the real concern will be if the 1mb chart starts downgrading or waning, at present it seems to be progressing nicely, there are always going to be upgrades and downgrades at this sort of range, even in the Stratosphere.

[Ruben Amsterdam]

GFS06z heats the top-strat to body temperature!

 

[chionomaniac]

GFS06z heats the top-strat to body temperature!

 

Yep just posted that on twitter - off to have a look at the rest of the strat now.

[Recretos]

More 3D stuff from the latest GFS. It basically shows the propagation of the warming, set at -46°C. Same thing, from different angles. Color means the height of the -46 isobar.

 

 

 

And two videos, animation, first showing the downward propagation of the warming, and the second is the heart of the vortex, which shows shrinkage at the later stages. Top is at 10mb.

 

db.tt/M0FSuyKH  db.tt/CnKoFchI

[Ruben Amsterdam]

Me again. Although not as fancy as the impressive (!) 3D modelling of the strat above, the map below shows that GFS12z increases heating at the top-strat even further. Where I thought the 6z might be a freak outlier, the 12z solidly confirms. Not only are temperatures at the 1mb level in FI now above 40 degrees Celsius, it also results in (in my eyes) promising geopotential maps. Surely if this materialises it must have an impact on the mid and lower levels of the stratosphere?

 

Edited December 9, 2014 by Ruben Amsterdam

[bluearmy]

Berlin will be showing the start of the warming on tomorrow's output. Tbh, it's showing this morning. The only thing that concerns me is that we haven't seen WSI tweeting some crazy T348 ECM ens mean chart yet!

the consistency of the gfs week 2 output surely means this is the real deal. The level of temps at 1 hpa probably overdone is is often the case at 2 weeks but even something less exhuberant will still do the job.

[Recretos]

JMA which is on a similar level as ECM, configuration wise, is already grabbing onto it. 

 

And yes, GFS has a positive temperature bias for top strat in deeper FI.

[Duane S.]

Berlin will be showing the start of the warming on tomorrow's output. Tbh, it's showing this morning. The only thing that concerns me is that we haven't seen WSI tweeting some crazy T348 ECM ens mean chart yet!

the consistency of the gfs week 2 output surely means this is the real deal. The level of temps at 1 hpa probably overdone is is often the case at 2 weeks but even something less exhuberant will still do the job.

I'd agree BA, without wishing to jinx it, it has been showing for long to enough to indicate it is the real thing and like you say even if 40 degrees (ridiculous) doesn't verify (which I doubt it will) something in the region of + 25 will do the trick and it does look like warming down to mid Strat as well this time. PLUS it has hardly come as the biggest surprise ever to see a big warming occurring as we enter the last third of this month, of this winter. Edited December 9, 2014 by s4lancia

[Skin]

Concerned over the MJO projections. Dies into the Circle of Death right as it nears Phase 7. 

[Recretos]

Concerned over the MJO projections. Dies into the Circle of Death right as it nears Phase 7. 

 

I wouldnt worry over it too much for now.

 

Since this thread is the best around for the stratosphere, I cant help myself not to post 3D animations of 4 SSWs that I have made. This layout includes: 3D is the isosurface of a certain temperature (written on the bottom, usually -45C), the bottom level is 150mb geopotential height, and the middle layer is 30mb geopotential height. This is layout version 1. In the version 1.2 I will include the heart of the vortex. But lets leave that for another time.

It is nicely seen how over the Atlantic, downward warmings really "ignite" tropospheric ridging with some delay, and how it cuts into the troposphere.

 

I made the layout as a preset, so once I tweak it, I can just put in any data, and simulate any SSW since 1950s, or as far as the datasets go.

https://db.tt/lZ0gAOWD

https://db.tt/co8AorvK

https://db.tt/t5PZ9bO2

https://db.tt/y3BvBQSL

 

And some other graphics I made today. Usually everything can be found on twitter where I stared posting a bit more recently. 

 

  

 

 

 

Regards