Stratosphere Temperature Watch

[chionomaniac]

Berlin still seems to be down.

Interested in the links ch but there is no rush.

Here they are:

Kuroda; http://www.mri-jma.go.jp/Dep/cl/kuroda/kuroda_publications_e.html

Pulvani: http://www.columbia.edu/%7elmp/pubs.html

Baldwin: http://www.nwra.com/resumes/baldwin/publications.php

Labitzke: http://strat-www.met.fu-berlin.de/labitzke/

Enough there to keep you busy for a while!

[knocker]

Here they are:

Kuroda; http://www.mri-jma.g...ications_e.html

Pulvani: http://www.columbia....7elmp/pubs.html

Baldwin: http://www.nwra.com/...ublications.php

Labitzke: http://strat-www.met...in.de/labitzke/

Enough there to keep you busy for a while!

Thanks- a slight understatement I feel. Especially as I'm ploughing through a book, Stratosphere Troposphere Interactions by Mohanakumar at the moment. Mind I can skip a fair bit of it as the maths are in the stratosphere! Will have to get JH to translate.

Edited November 7, 2010 by weather ship

[johnholmes]

Thanks- a slight understatement I feel. Especially as I'm ploughing through a book, Stratosphere Troposphere Interactions by Mohanakumar at the moment. Mind I can skip a fair bit of it as the maths are in the stratosphere! Will have to get JH to translate.

JH translate Maths, come off it Fred, you would be better asking next doors cat. I shudder whenever I open any of my theory books from Met College days!

Maths was never one of my strong points; most of us on the very first AMC course went to sleep reciting like zombies the thickness change equation or whatever we thought might come up in the next test or exam.

[cooling climate]

Weather Ship the link below is an excellent read explaining Ozone, QBO and Troposphere/

Stratosphere workings and along with diagrams explains many different aspects of the

Stratosphere in a much easier to understand way than many of the other papers out there.

http://www.ccpo.odu.edu/~lizsmith/SEES/ozone/class/Chap_6/index.htm

Edited November 7, 2010 by cooling climate

[knocker]

Thanks cc but how do I get from the link to the text? Fotget that.

Edited November 7, 2010 by weather ship

[johnholmes]

Weather Ship the link below is an excellent read explaining Ozone, QBO and Troposphere/

Stratosphere workings and along with diagrams explains many different aspects of the

Stratosphere in a much easier to understand way than many of the other papers out there.

http://www.ccpo.odu....hap_6/index.htm

yes tks for that CC, we oldies, Fred and I may well find it easier, well I can hope anyway, than some of the reading I've tried.

All a touch different to 1971 when I thought getting a forecast right beyond 24 hours was the bees knees!

[chionomaniac]

We are seeing a change forecast from stratosphere through to troposphere in the coming 10 days or so. The polar vortex has, until now, mainly been situated over the Siberian half of the Arctic Circle. This looks set to change stratospherically right up to 30 hPa with the vortex set to move more towards the Canadian portion of the Arctic. The tropospheric models look to be picking up on this transfer of energy and are showing this with reduced heights at the 500hPa level.

This could pave the way for the Scandinavian trough to slowly fill in, but it is far too early to suggest any ridging there as the polar vortex repositioning is likely to be transitory and more runs will be needed. This will be the time to see if there is any linkage to a change in emphasis with the PV, and the La Nina based GWO/ MJO patterns for about 2 weeks time.

There has been a recent small amount of warming in the mid stratosphere that looks to be coming to an end. However strong wave 2 activity is likely to create another warming at the 10hPa level that is wrapping itself around the vortex.

This warming looks to put some pressure on the vortex causing elongation. It is these tensions that can cause weakening and disturbances to the vortex. It is too early to say if that will be the case and I am awaiting todays GFS forecasts.

One other thing to note is that a recent paper by Labitzke (2007) showed that there had been no evidence of SSW's when the QBO was westerly during solar minimum years. Then 2 years ago we experienced the record SSW during one such time, so even though unlikely this year it can't be ruled out.

c

[chionomaniac]

We are seeing a change forecast from stratosphere through to troposphere in the coming 10 days or so. The polar vortex has, until now, mainly been situated over the Siberian half of the Arctic Circle. This looks set to change stratospherically right up to 30 hPa with the vortex set to move more towards the Canadian portion of the Arctic. The tropospheric models look to be picking up on this transfer of energy and are showing this with reduced heights at the 500hPa level.

This could pave the way for the Scandinavian trough to slowly fill in, but it is far too early to suggest any ridging there as the polar vortex repositioning is likely to be transitory and more runs will be needed. This will be the time to see if there is any linkage to a change in emphasis with the PV, and the La Nina based GWO/ MJO patterns for about 2 weeks time.

There has been a recent small amount of warming in the mid stratosphere that looks to be coming to an end. However strong wave 2 activity is likely to create another warming at the 10hPa level that is wrapping itself around the vortex.

This warming looks to put some pressure on the vortex causing elongation. It is these tensions that can cause weakening and disturbances to the vortex. It is too early to say if that will be the case and I am awaiting todays GFS forecasts.

One other thing to note is that a recent paper by Labitzke (2007) showed that there had been no evidence of SSW's when the QBO was westerly during solar minimum years. Then 2 years ago we experienced the record SSW during one such time, so even though unlikely this year it can't be ruled out.

c

Tonight's 18z GFS is exactly where I thought the stratospheric conditions and change in MJO forecast will be heading towards, with the Scandinavian ridge forming. I wish that I had been braver and suggested it outright before there was a suggestion on any models. Ah well, we all live and learn.

Edited November 9, 2010 by chionomaniac

[Southern Storm]

maybe the met office are thinking on the same lines as yourself, they are going for

an easterly later this month!

they must have someone reading this thread :winky:

[Glacier Point]

Oh and GP, Do you know of anywhere where there is a simple explanation of the E-P flux and its interactions and tropospheric sequelae? Thanks.

In a word. No !

After several weeks with a largely static ozone profile, things are on the move and this is also being mirrored by tropospheric changes to the polar vortex.

As a measure of the stratospherc circulation, we have seen a steady build up of ozone above the Northern Pacific. In the last few days this has dislodged and shifted rapidly eastwards. This seems to be impacting the tropopause given current modelling.

Comparison with this point last year provides some insight here:

2009:

2010:

Noticeably the tropical stratosphere has begun to warm in response to an increase in westerlies associated with the QBO.

http://ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/html_e/tlat_u30_nh.html

Key message: The polar stratosphere is going to get very unfriendly from here on in although the perverse warming of the the troposphere during the coolng phase is to be expected.

[chionomaniac]

I was just looking at the strat charts when you posted GP so thanks for the update.

The 10hPA forecast warming looks to fade away right in line with those ozone forecasts. To me it looks like the wave 2 induced warming is bouncing off the surf zone and not penetrating.

As I am always on the lookout for some hope though, here it is today. The 100hPa chart shows some interest at T+240 from the GFS (this is stratospheric FI at this level) with the suggestion of a vortex split.

Will it still be there tomorrow!?

Edited November 10, 2010 by chionomaniac

[SteveB]

In a word. No !

After several weeks with a largely static ozone profile, things are on the move and this is also being mirrored by tropospheric changes to the polar vortex.

As a measure of the stratospherc circulation, we have seen a steady build up of ozone above the Northern Pacific. In the last few days this has dislodged and shifted rapidly eastwards. This seems to be impacting the tropopause given current modelling.

Comparison with this point last year provides some insight here:

2009:

2010:

Noticeably the tropical stratosphere has begun to warm in response to an increase in westerlies associated with the QBO.

http://ds.data.jma.g...lat_u30_nh.html

Key message: The polar stratosphere is going to get very unfriendly from here on in although the perverse warming of the the troposphere during the coolng phase is to be expected.

When you say unfriendly, do you mean not favouring colder sloutions?

[Glacier Point]

That's correct Steve.

[SteveB]

Thanks for replying GP.

[Don]

That's correct Steve.

Are you still expecting a colder than average December, GP?

[knocker]

Just looking at a couple of ozone comparisons out of interest. I take it last year was a bit unusual or do I have to look at a few more years? Although I notice in 2002 totals were quite low.

[karyo]

Whereas it is good to see any above average temperatures in the stratosphere at this time of year, forecasts are suggesting that this will be temporary at both the 10hPa and 30hPa levels. What would be good to see is a sustained above average temperature anomaly at these levels. Going into this winter I suspect that this is unlikely, however, those ozone levels are higher than I would have expected so who knows?

Oh dear, stratospheric cooling here we come!

[knocker]

Looking back through the archives I notice that from 1951/2 there have been 22 Canadian Warmings during November and December. Does this normally require a split vortex with one over Canada? Sorry if this sounds a bit obvious.

[chionomaniac]

Looking back through the archives I notice that from 1951/2 there have been 22 Canadian Warmings during November and December. Does this normally require a split vortex with one over Canada? Sorry if this sounds a bit obvious.

Just quickly because I am at work the answer is no. The warming is over the Canadian segment (or Alaskan Pacific) and causes displacement of the vortex to the Eurasion segment along with some weakening.

[chionomaniac]

Today's update.

Yesterday, the T=240 forecast was suggesting some elongation of the stratospheric vortex at the 100 hPa level with the possibility of splitting. This remains the case today and interestingly this distortion of the vortex stretches right up to the top of the middle stratosphere. We have had a forecast of warming at the 10 hPa level which looks like occuring in the coming days without actually getting wrapped inside the vortex and it is probably this that is leading the change in stratospheric vortex profile. This can be seen quite clearly at the 10 hOa level on the ECM forecast.

The elongation is propagated right down to the 100 hPa level getting closer to the troposphere.

In fact at this level there is a suggestion of the vortex splitting but it is too early to say that this is going to occur.

The GFS is also suggesting a elongated vortex as the 30 hPA chart shows.

This type of event is always worth monitoring as a distorted vortex throughout the stratosphere will influence the tropospheric polar vortex positioning. It was the repeated splitting of the lower stratospheric vortex last year that led to polar air flooding southwards and northern blocking.

Cold spell on the way 10 days plus?

[nick sussex]

If the PV elongates but doesn't split then does this tie in with a broad swathe of high pressure across the Atlantic into Europe perhaps getting far enough north to deliver some colder continental air into the UK especially se areas and also into central and southern Europe?

[chionomaniac]

If the PV elongates but doesn't split then does this tie in with a broad swathe of high pressure across the Atlantic into Europe perhaps getting far enough north to deliver some colder continental air into the UK especially se areas and also into central and southern Europe?

Hi Nick. I first try and correlate the main centres of the tropospheric polar vortex with that of the lower stratosphere.

They should align somewhat. When looking at the ECM 100 hPa chart above ( the one that looks like ET's face) we can see a finger of troughing (ET's chin) heading towards the UK. This correlates quite well with the ECM 500 hPa tropospheric chart that also shows a weakened trough over the UK. The rest of the vortex position correlates really well.

The trick is working out how strong will any potential ridging be in between and at this timeframe one can only suggest where the rough positions will be( it also helps to look at the potential vorticity charts).

Because the stratospheric vortex position normally changes relatively slowly compared to the tropospheric vortex it can be a reasonable medium term guide.

[cooling climate]

I have been harping on about a much colder period coming the last third of November with

many in the UK seeing their first real taste of winter and judging by the stratosphere height

and temperature charts + the potential vorticity charts it does look more and more likely that

this will come from a more easterly direction than northerly.

I am still of the impression that there will be two main areas of vorticies one over north central

Russia and the other somewhere around Hudson Bay area during the winter months.

I was rather hoping we would see the effects of a earth bound M class solar flare from active

region 1121 on the stratosphere during a otherwise continued low solar activity phase but

alas region 1121 has weakened considerably.

[nick sussex]

Hi Nick. I first try and correlate the main centres of the tropospheric polar vortex with that of the lower stratosphere.

They should align somewhat. When looking at the ECM 100 hPa chart above ( the one that looks like ET's face) we can see a finger of troughing (ET's chin) heading towards the UK. This correlates quite well with the ECM 500 hPa tropospheric chart that also shows a weakened trough over the UK. The rest of the vortex position correlates really well.

The trick is working out how strong will any potential ridging be in between and at this timeframe one can only suggest where the rough positions will be( it also helps to look at the potential vorticity charts).

Because the stratospheric vortex position normally changes relatively slowly compared to the tropospheric vortex it can be a reasonable medium term guide.

Thanks Chiono, you're ET comparisons were very funny!

[chionomaniac]

The warming at the 10hPa level is really putting a squeeze on the stratospheric vortex right down to the troposphere. What is clear to see is that shape of the elongated vortex carries right down.

Forecast profile at 10hPa

http://wekuw.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ec.php?alert=1&level=10&forecast=all&lng=eng

From tropopause upwards at T+240

http://wekuw.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ec.php?alert=1&level=all&forecast=f240&lng=eng

Interestingly the 100hPa profile suggests blocking to the NE that slowly translates westwards towards Greenland as time progresses. Surely this has to lead to some kind of cold outbreak?

Edited November 12, 2010 by chionomaniac