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Stratosphere Temperature Watch 2012/2013


chionomaniac

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Posted
  • Location: Worcestershire
  • Weather Preferences: Forecaster Centaurea Weather
  • Location: Worcestershire

There are a couple of pages from a BDC paper I found that put waves into diagrams, always helps me, perhaps Ed can add further explanation to the below.

post-7292-0-45028500-1349299316_thumb.pn post-7292-0-40410800-1349299335_thumb.pn

The last diagram helped me picture the surf zone well.

post-7292-0-77124000-1349299552_thumb.pn

The paper is unfortunately too big to attach here, Dylan Jones, Dept of Physics, Toronto. 2005

The meridional circulation (Holton et al.) diagram shows nicely the process at play within ozone transport.

During an east phase of the QBO the wind shear is reduced over the tropics allowing tall thunderclouds to develop. The rising tropopause forces a column of air upwards which cools through adiabatic cooling. Hence we can almost measure the state of the BDC 'pump' through the autumn in stratospheric temperatures over the tropics. The colder the tropical stratosphere, the more ozone on its way poleward.

As the air descends over the Arctic, adiabatic warming takes places, promoting the conditions for ozone to persist, resulting in higher concentrations of ozone and further warming. There is a natural equilibrium but the stronger the pump, the greater the final concentration of stratospheric ozone.

Edited by Glacier Point
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Posted
  • Location: St Albans, 95m asl
  • Location: St Albans, 95m asl

Which I'm guessing means something like this:

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/01mb2525.gif

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/02mb2525.gif

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/05mb2525.gif

Isn't a great sign, although further down the stratosphere things are still below-well below average at present, I'm guessing that this warming might head down further with time?

SK

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Posted
  • Location: Edinburgh (previously Chelmsford and Birmingham)
  • Weather Preferences: Unseasonably cold weather (at all times of year), wind, and thunderstorms.
  • Location: Edinburgh (previously Chelmsford and Birmingham)

Sorry to be a bother, but has anyone any links to some past BDC data, as well as forecasts that go beyond 120 hours for the BDC (if there are any)? I've tried looking through the links on the Chiono's first post but I can't seem to find anything, unless I've missed something?

Thanks.

Edited by 22nov10blast
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Posted
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.
  • Weather Preferences: Snow and storms
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.

Sorry to be a bother, but has anyone any links to some past BDC data, as well as forecasts that go beyond 120 hours for the BDC (if there are any)? I've tried looking through the links on the Chiono's first post but I can't seem to find anything, unless I've missed something?

Thanks.

You have to check the ozone levels across the stratosphere

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Posted
  • Location: Edinburgh (previously Chelmsford and Birmingham)
  • Weather Preferences: Unseasonably cold weather (at all times of year), wind, and thunderstorms.
  • Location: Edinburgh (previously Chelmsford and Birmingham)

You have to check the ozone levels across the stratosphere

I realise this, I think I was having a bit of a brain fart when I posted as I meant to say 120+ forecasts for strat ozone levels. I've done a lot of searching but it appears as though the BDC is not measured in anyway, I was also after a dataset of values after failing to find one myself, but this doesn't exist so not to worry, ignore my last post.

Edited by 22nov10blast
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Posted
  • Weather Preferences: Cold and Snowy, Hot and Dry, Blizzard Conditions
  • Weather Preferences: Cold and Snowy, Hot and Dry, Blizzard Conditions

Thanks

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Posted
  • Location: Netherlands
  • Location: Netherlands

http://icdm2012.csp.escience.cn/dct/attach/Y2xiOmNsYjpwZGY6Mjc0NTE= Nice presentation by Adam Scaife. More can be found here http://icdm2012.csp.escience.cn/dct/page/65537

SUMMARY

  • NAO/AO are single largest source of variability in NH regional climate
  • Variability occurs on all timescales and is eddy driven
  • NAO/AO patterns govern the frequency of extreme events
  • The same patterns appear in response to a variety of forcings (degeneracy) and present a particular problem for detection/attribution studies
  • Strat-trop interaction important in many cases
  • New sources of conditional predictability are emerging but always limited by internal chaotic fluctuations
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Posted
  • Location: Netherlands
  • Location: Netherlands

Abstract

With extreme variability of the Arctic polar vortex being a key link for stratosphere–troposphere influences, its evolution into the twenty-first century is important for projections of changing surface climate in response to greenhouse gases. Variability of the stratospheric vortex is examined using a state-of-the-art climate model and a suite of specifically developed vortex diagnostics. The model has a fully coupled ocean and a fully resolved stratosphere. Analysis of the standard stratospheric zonal mean wind diagnostic shows no significant increase over the twenty-first century in the number of major sudden stratospheric warmings (SSWs) from its historical value of 0.7 events per decade, although the monthly distribution of SSWs does vary, with events becoming more evenly dispersed throughout the winter. However, further analyses using geometric-based vortex diagnostics show that the vortex mean state becomes weaker, and the vortex centroid is climatologically more equatorward by up to 2.5°, especially during early winter. The results using these diagnostics not only characterize the vortex structure and evolution but also emphasize the need for vortex-centric diagnostics over zonally averaged measures. Finally, vortex variability is subdivided into wave-1 (displaced) and -2 (split) components, and it is implied that vortex displacement events increase in frequency under climate change, whereas little change is observed in splitting events.

http://journals.ametsoc.org/doi/abs/10.1175/JAS-D-12-021.1

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Posted
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.
  • Weather Preferences: Snow and storms
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.

Abstract

With extreme variability of the Arctic polar vortex being a key link for stratosphere–troposphere influences, its evolution into the twenty-first century is important for projections of changing surface climate in response to greenhouse gases. Variability of the stratospheric vortex is examined using a state-of-the-art climate model and a suite of specifically developed vortex diagnostics. The model has a fully coupled ocean and a fully resolved stratosphere. Analysis of the standard stratospheric zonal mean wind diagnostic shows no significant increase over the twenty-first century in the number of major sudden stratospheric warmings (SSWs) from its historical value of 0.7 events per decade, although the monthly distribution of SSWs does vary, with events becoming more evenly dispersed throughout the winter. However, further analyses using geometric-based vortex diagnostics show that the vortex mean state becomes weaker, and the vortex centroid is climatologically more equatorward by up to 2.5°, especially during early winter. The results using these diagnostics not only characterize the vortex structure and evolution but also emphasize the need for vortex-centric diagnostics over zonally averaged measures. Finally, vortex variability is subdivided into wave-1 (displaced) and -2 (split) components, and it is implied that vortex displacement events increase in frequency under climate change, whereas little change is observed in splitting events.

http://journals.amet.../JAS-D-12-021.1

Thanks for the links sebastiaan.

I suspect that the decimal point is in the wrong place above!

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Posted
  • Location: Edinburgh (previously Chelmsford and Birmingham)
  • Weather Preferences: Unseasonably cold weather (at all times of year), wind, and thunderstorms.
  • Location: Edinburgh (previously Chelmsford and Birmingham)

Thanks for the links sebastiaan.

I suspect that the decimal point is in the wrong place above!

Shouldn't it be 7 per decade? I was under the impression that they happen approximately once every two years.

Thanks as well Sebastian.

Edited by 22nov10blast
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Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

http://icdm2012.csp....jpwZGY6Mjc0NTE= Nice presentation by Adam Scaife. More can be found here http://icdm2012.csp..../dct/page/65537

SUMMARY

  • NAO/AO are single largest source of variability in NH regional climate
  • Variability occurs on all timescales and is eddy driven
  • NAO/AO patterns govern the frequency of extreme events
  • The same patterns appear in response to a variety of forcings (degeneracy) and present a particular problem for detection/attribution studies
  • Strat-trop interaction important in many cases
  • New sources of conditional predictability are emerging but always limited by internal chaotic fluctuations

thanks for that Sebastian, I can't pretend to have absorbed all of the first link but it is very well presented, argued and helped by very good illustrations. Not looked at the second one yet.

Will download both for a leisurely read on Sunday.

I would recommend anyone to read the link at least to the first one.

What impresses me is that a highly respected Met O researcher has shown an ability to illustrate so clearly what he is trying to explain. In my days the visual presentation of 'normal' forecast staff was excellent the likes of his predecessors was abysmal, so a great step forward there.

Edited by johnholmes
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Posted
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.
  • Weather Preferences: Snow and storms
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.

thanks for that Sebastian, I can't pretend to have absorbed all of the first link but it is very well presented, argued and helped by very good illustrations. Not looked at the second one yet.

Will download both for a leisurely read on Sunday.

I would recommend anyone to read the link at least to the first one.

What impresses me is that a highly respected Met O researcher has shown an ability to illustrate so clearly what he is trying to explain. In my days the visual presentation of 'normal' forecast staff was excellent the likes of his predecessors was abysmal, so a great step forward there.

It's a pity that it wasn't videoed, John.

Also of note in the presentation is the slide documenting the phase of the MJO and linkage to the NAO, with phase 3 having a high corellation to a strongly positive NAO and phase 7 to a strongly negative NAO.

Link to Lins powerpoint presentation

http://www.google.co...LCk4M301ABb_LLg

and here

http://www.google.co...WPCtWWr-Ku7QXIA

http://www.ecmwf.int/newsevents/meetings/informal_seminars/abstracts/2012/Brunet.pdf

Edited by chionomaniac
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Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

Like you say chio-a pity its not a video, I may write to R Met Soc for the local Leeds branch to ask if they could persuade him to do a talk there?

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Posted
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.
  • Weather Preferences: Snow and storms
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.

Like you say chio-a pity its not a video, I may write to R Met Soc for the local Leeds branch to ask if they could persuade him to do a talk there?

I have just edited in Lins powerpoint presentations, fascinating stuff here.

Shouldn't it be 7 per decade? I was under the impression that they happen approximately once every two years.

Thanks as well Sebastian.

Yes

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Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

It's a pity that it wasn't videoed, John.

Also of note in the presentation is the slide documenting the phase of the MJO and linkage to the NAO, with phase 3 having a high corellation to a strongly positive NAO and phase 7 to a strongly negative NAO.

Link to Lins powerpoint presentation

http://www.google.co...LCk4M301ABb_LLg

and here

http://www.google.co...WPCtWWr-Ku7QXIA

http://www.ecmwf.int...2012/Brunet.pdf

thanks for those links chio-Sunday seems to be planned out with Met reading!

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Posted
  • Location: St Albans, 95m asl
  • Location: St Albans, 95m asl

Well after some recent warming, the tropical stratosphere is starting to cool once again all the way up to the 2mb level, with the polar stratosphere remaining at bang on average values

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/

Chio, are there any examples of winters where it was merely a cool tropical stratosphere that led to a blocked N Hemisphere pattern as opposed to any significant warming of the polar stratosphere?

Edited by snowking
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Posted
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.
  • Weather Preferences: Snow and storms
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.

Chio, are there any examples of winters where it was merely a cool tropical stratosphere that led to a blocked N Hemisphere pattern as opposed to any significant warming of the polar stratosphere?

I have not looked in enough detail sk.

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Posted
  • Location: @scotlandwx
  • Weather Preferences: Crystal Clear High Pressure & Blue Skies
  • Location: @scotlandwx

Lin ppt is good reading, looks like the MJO when active has strong correlation and is still a good lead.

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Posted
  • Location: Nuneaton,Warks. 128m asl
  • Weather Preferences: Snow then clear and frosty.
  • Location: Nuneaton,Warks. 128m asl

I just wondered in a quiet MJO phase as now where we have low amplitude and a weak ENSO state whether the Stratosphere becomes even more of a driver of the NH pattern.?

Just thinking aloud Ed and i may be oversimplifying things but i am sure i read this somewhere.

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Posted
  • Location: st albans
  • Location: st albans

I just wondered in a quiet MJO phase as now where we have low amplitude and a weak ENSO state whether the Stratosphere becomes even more of a driver of the NH pattern.?

Just thinking aloud Ed and i may be oversimplifying things but i am sure i read this somewhere.

i guess thats straightforward logic phil. we know there are many pieces of the jigsaw and if a few of them seem to be out of the equation, then those which remain will assume more importance. wonder what we will be left looking at if the strat is average come late october ?

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Posted
  • Location: Nuneaton,Warks. 128m asl
  • Weather Preferences: Snow then clear and frosty.
  • Location: Nuneaton,Warks. 128m asl

i guess thats straightforward logic phil. we know there are many pieces of the jigsaw and if a few of them seem to be out of the equation, then those which remain will assume more importance. wonder what we will be left looking at if the strat is average come late october ?

Yes i guess you are sort of thinking along simliar lines to me Nick.I am sure there are things to consider-less Ice cover for instance and any effect, if any, that will have on blocking patterns.

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Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

Some musings after reading the various links given yesterday.

Once again the papers show that you cannot take any single meteorological parameter on its own. Everything is linked to everything else.

Re the effect a strong NAO may have on the MJO

Also that MJO convective anomalies reaching the western Pacific can trigger 5-15 days down the line an increase in NAO amplitude

SST anomalies in November are a reasonable indicator of the type of winter=+ve NAO or -ve NAO

a lot of work is being done professionally in attempting to get some kind of forecast criteria for MJO, Troposphereic effects, AO/NAO, SST anomalies, their possible links, and any subsequent way of predicting the coming winter.

very interesting reading and I did understand much of it although I intend to leave the issue of any forecast to others better qualified.

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Posted
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.
  • Weather Preferences: Snow and storms
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.

I should also point out that from the stronger the mountain torque observed, we can forecast that the wave break into the stratosphere will be stronger. So that this is a useful guide as to what occurs down the line.

Also, in todays forecasts there is a strong 10 day trend to displace the polar vortex towards Baffin bay/ N Canada region. So will we see some kind of height rises in the Scandi region around this time tropospherically - not programmed as of yet!

(Edit - of course these height rises could be Eurasion placed)

Interesting, these are starting to show now on the ECM and UKMO!

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