Stratosphere Temperature Watch 2012/2013

[sebastiaan1973]

That's a nice experiment Chio!

Interesting. They refer to Cassou's article in Nature. http://www.nature.co...ature07286.html

In 2008 Cassou made a presentation with this subject, which can be found here: http://www.cerfacs.f...cassou_2008.pdf

In my opinion it's an excellent presentation. Nicely illustrated and clearly written.

Edited October 14, 2012 by sebastiaan1973

[snowking]

10mb temperatures also showing a uptick.

Even more so at 30mB

http://ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/gif/pole30_nh.gif

However, is this not more arctic than polar?

Over the polar regions:

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/30mb9065.gif

Still close to normal

The encouraging thing is the continued decline across the tropics:

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/30mb2525.gif

With the biggest concern perhaps being the upper levels of the polar Strat, most notably at 2mB:

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/02mb9065.gif

So hopefully we don't see too much downwelling from that

[chionomaniac]

Thanks once again Seb.

This is quoted in the paper

45 Fig. 6 shows that about 10 days after the MJO passes its phase with reduced (enhanced)

46 convection over the western Paciï¬c (Indian) Ocean [phase 1 as deï¬ned by Wheeler and

47 Hendon, 2004], warm anomalies are established in the polar lower stratosphere.

and the current MJO forecast:

Let's watch and learn!

Stage 1

70hpa today:

70 hPa T+240

A slight warming forecast - but too small to be significant.

[johnholmes]

That's a nice experiment Chio!

Interesting. They refer to Cassou's article in Nature. http://www.nature.co...ature07286.html

In 2008 Cassou made a presentation with this subject, which can be found here: http://www.cerfacs.f...cassou_2008.pdf

In my opinion it's an excellent presentation. Nicely illustrated and clearly written.

a fascinating read

[lorenzo]

This subject has been lifted in the media perhaps by Glosea4 and Meto displaying more interest, whether science can be in vogue I guess is a subject for its own discussion as trends change over time.

Still, here is a paper over 5 decades old to prove this subject is not just a new fad...

Vintage MMW.pdf

Converted this table from openoffice to xls so not sure who it will appear if you open it.

Collated NAO / AO / ENSO / QBO / Solar Cycle / FU Berlin Strat Table for reference.

Analogs.xls

Edited October 14, 2012 by lorenzo

[sebastiaan1973]

Moving on back to the stratosphere....

We are still seeing a cooling of the mid stratosphere occurring in line with seasonal expectations.

It is still early and I would not expect anything other at this stage.

I suspect that the southern hemisphere situation will affect the northern hemisphere and we should now be looking for some strong NH wave activity to assist feedback into the stratosphere. On this point alone the GFS NH pattern from the 00Z would be very welcome.

Chio, if I understand well, the pushing of warmer air into the northpole around Alaska is a good thing?

[bluearmy]

Chio, if I understand well, the pushing of warmer air into the northpole around Alaska is a good thing?

Gets even better in ECM fi with thicknesses in the mid thirties and uppers around 4c headed for the pole. Wonder what tomorrows Berlin fi strat forecasts will look like as they are derived from the ECM 12z op run.

[chionomaniac]

I have to say as someone who is looking for feedback mechanisms that could potentially disrupt the lower stratospheric vortex, tonights output does have me rubbing my hands together in anticipation. Let's hope it comes to fruition.

Edited October 14, 2012 by chionomaniac

[Glacier Point]

Indeed Ed, a meridional pattern in the Atlantic as we head towards November = excellent surface flux for later in the season.

Current zonal winds are still running 'light' between 10m/s and 15m/s at 70N, which is still very much in line with similar QBO analogues. Looking these analogues, weakening east QBOs have their fair share of warming events.

[sebastiaan1973]

Good morning. EC 216. Look at these 850 temperatures around Alaska.

[MattH]

The signal for a warming event associated with more anticyclonic conditions beyond 216hrs (as Seb mentions in recent post above) continues within the GFS as well, especially at 50hPa, but at 30hPa to an extent also...

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/gif_files/gfs_t50_nh_f240.gif

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/gif_files/gfs_z50_nh_f240.gif

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/gif_files/gfs_t30_nh_f240.gif

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/gif_files/gfs_z30_nh_f240.gif

Looking at the GFS and more particularly the ECMWF ENS clusters out to 364hrs, there remains no significant evidence within tropospheric charts anyway, for a rapid progression towards a major PV in and around the Greenland region as is an increasing risk at this time of year. The word 'meridional' was mentioned in previous posts and that signal is most certainly present with a particularly meridional pattern evident within the ensembles. Certainly creates a day to day forecasting headache mind, that kind of pattern!.

Despite the expected and seasonal cooling of the strat of late and up to present day, I don't think things are looking too bad at all at the moment with promising signs evident.

Have a good week, Matt.

[chionomaniac]

Matt, the GFS updates around 11-12pm GMT, so they are yesterdays 00Z charts.

The ECM updates around 5am with yesterdays 12Z run.

Would agree with the promising signs.....

[chionomaniac]

Furthermore, I have just checked the ECM charts and there are early signs of wavenumber 2 activity later in the output in the tropopause - something that I would expect given the current NH forecast profile. The question remains as to what extent that this can effect the lower strat.

Still early days.

Edited October 15, 2012 by chionomaniac

[AWD]

I'm no expert when it comes to the Stratosphere, but isn't this a positive early note;

http://t.co/cqGxuW8F

[bluearmy]

I'm no expert when it comes to the Stratosphere, but isn't this a positive early note;

http://t.co/cqGxuW8F

certainly not negative AWD. early days as chio says but heading in the right direction

[syed2878]

so what does this all means for us on the ground chio?

[Gavin Hannah]

So, looking good, add 6 weeks for time lag... that would take us to start of December.

[lorenzo]

Another link from last year with some good gifs of Vorticity and Temps.

http://www.met.rdg.ac.uk/Data/CurrentWeather/

[lorenzo]

Spent some time today looking through the archive of Canadian Warming events and years, what do you know the only year to reflect ENSO, QBO and comparable position in solar cycle for a November warming, 1962. Overall the majority of Canadian warmings occur in November with only 3 in ENSO neutral years, the other 2 being 1952 and 1980 where the QBO was in the opposite phase. So back to 62 we go..

It would seem that any November Canadian warming event purely on a statistical basis is more common in an ENSO year, with this in mind 1977 was worth a look, just into Nino territory after neutral earlier in the year. 1958 and 1977 whilst similar are at solar maximum and minimum respectively. 1977 climbing from a minimum, similar to now.

Looking at December, 1954, 1965 and 1981 lead with an easterly QBO. Within these 54 is Nina and 1965 is a strong Nino event, leaving 1981.

Overall the majority of Canadian warmings occur in November with only 3 in ENSO neutral years. Last one at all was 12 years ago, the largest break in events previously was 81-91, are we 2 years overdue. Entirely plausible. November looking more likely for an event if Nino gets going. December if we stay as we are..

[Mark Neal.]

Spent some time today looking through the archive of Canadian Warming events and years, what do you know the only year to reflect ENSO, QBO and comparable position in solar cycle for a November warming, 1962. Overall the majority of Canadian warmings occur in November with only 3 in ENSO neutral years, the other 2 being 1952 and 1980 where the QBO was in the opposite phase. So back to 62 we go..

It would seem that any November Canadian warming event purely on a statistical basis is more common in an ENSO year, with this in mind 1977 was worth a look, just into Nino territory after neutral earlier in the year. 1958 and 1977 whilst similar are at solar maximum and minimum respectively. 1977 climbing from a minimum, similar to now.

Looking at December, 1954, 1965 and 1981 lead with an easterly QBO. Within these 54 is Nina and 1965 is a strong Nino event, leaving 1981.

Overall the majority of Canadian warmings occur in November with only 3 in ENSO neutral years. Last one at all was 12 years ago, the largest break in events previously was 81-91, are we 2 years overdue. Entirely plausible. November looking more likely for an event if Nino gets going. December if we stay as we are..

Great Analysis i find all these posts intriguing, but when you mention December, do you mean that is when you expect a development in warming or potential for wintry conditions here? Thanks.

[lorenzo]

Am not experienced, bold, crazy* enough (delete as applicable) to make any kind of public prediction for Winter Mark, will leave that to the folks with much better expertise who can provide a more qualified analysis and explanation.. Matt, Chiono, GP, S Murr to name a few.

I enjoy crunching through data and papers for clues and learning - cannot deny the excitement and the potential for this Winter to deliver some exceptional weather. As for when who knows !!

[Radiating Dendrite]

Quick Question - Can we get SSW events all year round? Do we get SSC events in Summer?

[sebastiaan1973]

Quick answer: no.

[Suburban Streamer]

So, looking good, add 6 weeks for time lag... that would take us to start of December.

Lag time of 4-6 weeks from a ssw not from a little bit of warming. We have not had a ssw, so far too early to set the egg timer for 6 weeks...

Edited October 15, 2012 by Suburban Streamer

[bluearmy]

Lag time of 4-6 weeks from a ssw not from a little bit of warming. We have not had a ssw, so far too early to set the egg timer for 6 weeks...

It isnt even that straightforward. you can get an almost immediate trop response from some warmings. the general currently accepted situation is a lag of 4 to 6 weeks for a trop response as you say. however, different types of warmings will have different lag times depending on their nature. still too early to be getting too excited by strat events unless it looks as though there could be a feedback loop setting up.