Stratosphere Temperature Watch 2013/2014

[Snowy L]

East QBO, dropping solar flare and El Nino would be a very nice start to winter next year.

 

Edit: 06z giving us incredible temperature charts by the way. I think it might have picked up on the wave-2 signal

 

 

 

 

Ok seriously, what?!?

 

Surely an error?

Edited January 25, 2014 by Snowy L

[feb1991blizzard]

Ok seriously, what?!?

 

Surely an error?

 

 

Its very near to an SSW, if not one, looking at the heights charts.

 

 

Ironically on the day when we could be about to suffer an almighty day of downgrades tropospherically speaking.

Edited January 25, 2014 by feb1991blizzard

[bluearmy]

worth a look for the heights on that run!  looks like one of the 'boom' gefs runs recretos was illustrating recently.

[chionomaniac]

First technical SSW forecast...

 

Edited January 25, 2014 by chionomaniac

[lorenzo]

Recretos - stop playing in your bucket and get that monster gridded up !!

 

^^ A Real BOOOM Chart..

Edited January 25, 2014 by lorenzo

[bluearmy]

First technical SSW forecast...

 

at T300 aswell.  interesting to see the latter stages of the trop sending the siberian vortex this way a few days later .............

[chionomaniac]

That is the first stratospheric BOOM of the season!

 

long way to go...

[karyo]

Spectacular 6z but it is at odds with what we've seen in previous runs so caution is needed as it may be a one off.

 

Karyo

[Recretos]

Well. Where to begin. 

 

For now, lets just say that this run actually looks like an amplified version of the recent GEFS ensemble mean scenarios. It even caught me as a surprise, and such a change in just one run, does imply that there is some major change in the model forcing (or a run error). I haven't looked at any charts yet, but my bet would be on EAMT (among other things) like on a few occasions so far. 

 

I also checked the input data for the 6z run and even tho the main critical data was complete, there was actually an overage of one segment, but 3 opportunity inputs were actually at zero (no input data). The GPS integrated precipitable water, Multi-Agency Profiler (MAP) + SODAR winds and RASS temperatures (NOAA and Multi-Agency). I guess that the 12z will show if the input data played a role, or perhaps GFS finally sobered up and decided to follow its ensemble cousin. 

 

I will add a few graphics later in the evening, once the 12z runs gets out. Dont want to spend 2 hours making graphics for a possible run error (hopefully it is "too legit to quit").

 

Recretos - stop playing in your bucket and get that monster gridded up !!

 

^^ A Real BOOOM Chart..

 

Sometimes the only way to get an SSW, is in your bucket. 

 

And yes, as some have said it before me, 06z is officially with an SSW, with -5m/s U-mean U-wind at 60N@10mb. At T300, there is no technical SSW.

 

 

 

And the 3D profile: From top down, 1mb, 3mb, 5mb, 10mb and 30mb. It shows the geopotential height in 3D and color. The perspective is the "USA in front" like on the Instant weather maps. That 30mb level just doesn't want to give in (also trying to be too legit to quit :lol:) , tho it is severely weakened. 

 

 

 

Best regards.

Edited January 25, 2014 by Recretos

[Ruben Amsterdam]

 

 

 

I just love these graphs. So illustrative! 

 

It strikes me as a rather large coincidence that GFS 06z with its downgraded/different tropospheric pattern (as opposed to previous runs) shows an excellent stratospheric run. Any major differences in terms of MT events between the 06z and 00z?

Edited January 25, 2014 by Ruben Amsterdam

[Interitus]

 

 

That reminds me of an experiment I used to play with, when trying to simulate a mesocyclone. I used a large bucked (150l of water ), and I put some very fine dark soil at the bottom. I filled it up with water and then I spin the whole mass really fast. Then I watched how the vorticity from the large spinning water mass gets increased and focused on small specific random locations at the bottom (or like ground surface in reality) where the soil was, and it even formed quasi-funnel shaped forms. it lasted for a short period and then disappeared and reappeared at a different random location. I was basically simulating tornadogenesis by fluid dynamics.

Now you could try this at home, and when you spin up the water mass, you will notice how in the centre the water level will decrease, and on the sides the water level will increase. That is pretty much an accurate simulation of the geopotential height and now you have your own atmosphere dynamics in your bucket.  Now you put your hand top down into the water surface, deeper each time, and observe how the dynamics change with depth. It is nice if you have some very fine soil or some fine light material in the water, so you can actually see how the flow changes with depth. You can actually simulate your own SSW with fluid dynamics, which is pretty much what our atmosphere is "running on". I am also thinking of ways to simulate wave 2. I have thought about inflating balloons, but I guess I need to think some more.  I really hope someone will decide to make this experiment, because it is first hand intro into stratospheric dynamics, and pretty much as close as you can get at home to simulating stratosphere/polar vortex without a computer.

 

 

 

A vortex formed in a bath or sink is a good way to examine the dynamics. The vortex can withstand some disturbance, but too much and it crashes down.

Anyway, try putting an object in the bottom of your bucket and you can simulate stationary wave forcing similar to the typical fluid dynamic rotating water tank experiments, as demonstrated here explaining Rossby waves -

http://geosci.uchicago.edu/~nnn/LAB/DEMOS/RossbyWave.html

[bluearmy]

Is it really T384 before the winds reverse @ 60N recretos? Looked like it would be earlier based on those heights. still, at t 300, its clear there is no way back on that run.

[cooling climate]

 

A change in geopotential height from wave activity is not a change in temperature, no matter how intrinsically the two may be linked so it is not misleading at all, cc. It is better to be accurate and differentiate between the two, so that confusion doesn't occur.

As you said they are intrinsically linked. You can not have one without theother.Recretos the warming and gph that you show for 03.02.14 only shows one warmingbecause the warming on the pacific side had dissipated from the warming ongoingat the moment.

[Snowy L]

Clear split at t276

http://www.instantweathermaps.com/GFS-php/showmap-strat.php?run=2014012512&var=HGT&lev=10mb&hour=276

 

Temperatures looks promising as well

 

[Ruben Amsterdam]

GFS12z verifies! Stuff just got interesting!




Edit: ok, not as impressive as the 06z at the end, but certainly not a bad run.

Edit edit: two ensembles (12z) made by Lars form our Belgain/Dutch forum weerwoord.be. 10 hpa zonal mean winds at 60N and 10hpa temps at 90N. I suspect the differences between operationals and members (early in the run) is due to resolution issues.

Edited January 25, 2014 by Ruben Amsterdam

[Recretos]

Is it really T384 before the winds reverse @ 60N recretos? Looked like it would be earlier based on those heights. still, at t 300, its clear there is no way back on that run.

 

Yes, it reverses from 372 to 384. At 300, the zonal mean-zonal wind is ~+12m/s at 60N@10mb. What this calculates is basically the zonal (U) component of the mean wind field. More meridional (V) is the wind, lesser the U component. Basically the "angle of attack" of the wind towards the pole (or down from it) plays a role. Talking about the geostrophic wind of course. Negative (positive) zonal mean on its own does not mean or guarantee that the wind is blowing in a straight line from east (west). 

 

Yesterday i was talking about waves, so today let me give you a crash course in the infamous zonal mean - zonal wind section. 

 

There was an easterly component at 300, but under a steep angle, while the west component was under a lower angle, adding more positive zonality in the mean at 60N.

I drew (veeery poorly) the wind vectors, which are not really meant to be proportional to the amplitude. Blue vectors have a west (positive) U component (wind crossing the lat. line on a W->E orientation), and the violet vectors having an east (negative) U component (vice-versa). White line is the 60N lat. line. 

Basically you can see that there is not much zonality at all, with the intense wave 2 making the main jet pretty much meridional at 60N, which can reduce the amplitude of the zonality in general. But the zonal components that remain are more westward than eastward. And the speed of the west "components" is greater in average (zonal mean) than its east counterpart. 

 

As for the 384: Here we have much more and stronger east U-components. The zonal mean was -5 in comparison with the +12 at 300h. 

 

 

The bottom line is: You can give a good estimate of a mean zonal U-mode (east or west) from height charts, but nothing tops calculations. Especially when you want to point at the exact time of the zonal reversal. For example, you misjudged it by 72 hours.

You can also draw like I did, but you still cant get an exact clue just how strong is the orientation of the U-component of the geostrophic wind

 

Unless I plot you the actual zonal components.  I actually plotted this after I drew the top charts and it seems my estimate was quite good. Its not really that hard to see the orientation, but the intensity is another story.

 

 

 Recretos the warming and gph that you show for 03.02.14 only shows one warming

because the warming on the pacific side had dissipated from the warming ongoing

at the moment.

 10mb now.gif

 

I have noticed that. And you notice that the temperature wave dissipates, while the geopotential wave remains. So at that point you can have wave 2 and 1 temperature wave. I completely understand what your point is, but for the sake of people who are not so familiar with this, lets keep it to the basics, and say that the wave 1 and wave 2 that we usually talk about, refer to geopotential waves. We have separate calculations for temperature waves.

 

 

On a side note: 12z is actually a downgrade, and it does not have a reversal at 384h (not even close actually). The zonal mean zonal wind is at 21 m/s at 60N@10mb.

 

@Ruben: The difference is expected, since the members are perturbed. And of course the resolution does indeed play a role. And that is actually quite a spread, showing just how complicated things are at the moment for forecasting the medium-long term development in the stratosphere. 

 

Regards.

Edited January 25, 2014 by Recretos

[lorenzo]

Continued excellence Recretos. Thank you again for the work put in to your posts. Interitus, great link, the Index page also has some amazing fluid dynamic videos of the effects of Mountain Torques. Great find.

[lorenzo]

ECM serves up a vortex split at 10mb on this mornings 10 day chart.. 

 

Infact, vortex prerty much carved at all levels ! http://users.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ec.php?alert=1&level=all&forecast=f240&lng=eng

 

[karyo]

ECM serves up a vortex split at 10mb on this mornings 10 day chart.. 

ecmwf10f240.gifecmwfzm_u_f240.gif

 

Infact, vortex prerty much carved at all levels ! http://users.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ec.php?alert=1&level=all&forecast=f240&lng=eng

Indeed  and the 0z GFS has a sustained split too! 

 

Karyo

[Recretos]

When comparing the latest GFS and ECM, it is clear that ECM has a more beat up vortex. As also seen on the zonal mean zonal wind chart. Not by much, but it can affect the ongoing development in the model. 

 

 

 

  

[Duane S.]

ECM serves up a vortex split at 10mb on this mornings 10 day chart.. 

ecmwf10f240.gifecmwfzm_u_f240.gif

 

Infact, vortex prerty much carved at all levels ! http://users.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ec.php?alert=1&level=all&forecast=f240&lng=eng

Ha beat me to it was about to post the same two charts from the ECM!

 

Certainly the zonal wind chart looks very promising at D10, very conducive to the setting up of some serious HLB if that verifies.

 

I'm liking the look of the forecast wave 2 profile as well, seems to downwell nicely...

[dec10snow]

I know nothing about the strat in order to comment on it, but I pop in here now and again and look at some posts, and it seems to me that the warmings that show up always seem to be at the end of the run, and still aren't getting any closer?!

Or is this just me not seeing everything as I only have a look every couple of days??

[Cloud 10]

06z GFS looks "encouraging" in FI 

 

[karyo]

A truly awesome 6z forecast for the stratosphere! Very similar to yesterday's 6z actually.

 

Whether it is overdoing it or not it is important that we have consistency in terms of the split which happens around 180 hours so not exactly FI anymore.

 

Karyo

[chionomaniac]

Looks like the 06Z is becoming the 'SSW run!'