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#1188254 - 07/04/2013 20:10 Stratospheric sudden warmings (SSWs)
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
Found this link about the SSW event of January 2013.
"Stratospheric sudden warmings (SSWs) are a ubiquitous feature of the wintertime flow in the northern hemisphere."

This looks to be an amazing documentary of this event.

GEOS-5 Analyses and Forecasts of the Major Stratospheric Sudden Warming of January 2013

http://gmao.gsfc.nasa.gov/researchhighlights/SSW/

Enjoy! grin
Have a look at the time series of the event on sat pic
and the in depth scientific explanation of some of the parameters

Going to read this tomorrow..Looks to be a great presentation



Edited by crikey (07/04/2013 20:10)
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#1189298 - 13/04/2013 15:46 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Seira Offline
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Registered: 27/08/2003
Posts: 7166
Loc: Adelaide Hills.
Thanks for the link crikey smile .

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#1197170 - 02/06/2013 19:41 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
Hey.Look at this! Really exciting.
I just caught site of this amazing 10mb warm anomaly occurring in the southern ocean south of the OZ mainland atm.
Is that a stratospheric warming event underway?? In the southern hemisphere.!!
Aren't they rare?

The animation sourced from

http://theweathercentre.blogspot.com.au/2013/03/2013-official-severe-weather-outlook.html

This is animation is hotlinked and should update.



and a still snap l have taken for future reference

Commenced 23rd may 2013 and the snap taken on the 29th of may 2013

Will be interesting to see what this looks like now..The2nd June 2013?

These events are renowned for bringing severe weather in connection with cold snaps and snow l believe.
as downwelling of cold stratospheric air to the surface.
It appears to have emerged from the Antartic and has moved into the sub polar latitudes.
Can anyone confirm this?

It could turn the AAO/SAM highly negative??





Edited by crikey (02/06/2013 19:44)
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#1197181 - 02/06/2013 20:32 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Things Offline
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Registered: 29/11/2009
Posts: 8400
Loc: Blair Athol, SA
Interesting, might have to go do a bit of reading on these smile

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#1197208 - 02/06/2013 23:00 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
MOUNTAIN h2o Offline
Weather Freak

Registered: 23/03/2012
Posts: 682
Loc: Hobart Lenah Valley Tas 198 as...
Crikey , you may I have found the answer to what no one else has been able to answer on the Tassie Forum. As far as I'm concerned you are a genius!! I've been banging on ( sorry whinging wink ) that we are cooking in Hobart. Around the date from this pattern we have had days way over average . Infact this week ahead is just incredible day after day of temps around 17 /18 and it should be 12 and Winter. No sign of this abating either. I knew something was very amiss, you may very well have found the answer. Any further info from anyone or yourself would be greatly appreciated. Awesome find that's for sure.
Cheers from
Hobart the center for climate extremes !!

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#1197223 - 03/06/2013 07:35 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
GrizzlyBear Offline
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Registered: 23/06/2011
Posts: 2359
Loc: Yetholme [1180m] Central Table...
Could that SSW could have anything to do with the drop in AO in the NH. From what I see though, AO was already low in Dec/2012, but perhaps the two still are related. I wonder if that small patch of SSW south of Hobart could have been related to the drop in SAM second half May. However it was only a small brief drop, also the temperatures changes in SSW have been as much as 25deg in NH but only about 7deg in that patch south of Hobart. If that theory is right then that SSW south of Hobart is gone now given the rise in SAM and further forecast rise as well. Thoughts?

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#1197248 - 03/06/2013 10:21 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW
Here's a few documented SSW events in the SH.

Says there was an SSW event as recently as October 2012, but before that 2002.

http://curriculum.pmartineau.webfactiona...ern-hemisphere/

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#1197269 - 03/06/2013 12:44 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW
Apparently the 2002 even was the first major SSW event documented in the SH, very interesting.

http://www.atmosp.physics.utoronto.ca/SPARC/News20/20_Baldwin.html

So it seems these events have a tendency to excite the SAM sending into negative territory. Amazingly the SAM bottomed out at -10.71 during that event. If I remember correctly though we baked in very hot conditions through Sep/Oct 2002, so not really seeing the connection to cold conditions during these events, at least in the SH.

Thanks for bringing this to our attention Crikey! smile

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#1197317 - 03/06/2013 19:29 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
Hey..Thanks for your interest 'guys' . The animated image is even looking better for the 31st May 2013..
I have been looking around for some answers myself.

Considering the rarity of such an event l am a bit astonished nothing has appeared on the WWW as yet?

The NOAA observation of the Antartic oxone and stratosphere watch does not switch over from the NH until JULY..l believe.

Wondering how long the SSW event takes from start to finish?

Seems too early in winter for an SSW?

I am in the process of collecting some souvenir snaps and research info' which l will post in the coming days..

Thanks for the links thus far. I am reading.

Mountain H20.I am not sure re: your warm tassie' anomalies.
What you suggest is not impossible as large perturbations like this in the atmosphere will produce a change in Jetstream behaviour at the horizontal layer and will produce waves in response both vertically and horizontally.
This is a bit like an atmospheric volcano.
Warm air is 'spewed' in to the stratosphere. As you would expect ,the flow on waves would be significant.

I agree CS. The SH ocean is more likely to buffer sharp atmospheric shifts.. Lets see?

GB. The NH events and SH SSW(Sudden stratospheric warming ) events are not related directly as they are events that occur on and near the poles in winter.

SSW's are on the increase in the NH. Wonder if that will happen in SH as well..


One thing l have noted is the appearance of the sub polar jet., Very suddenly.This week ..
Look at the WZ sat' pic on the right of your screen and you can see how white the cloud is along the polar jet. Part of Heading your way Mountain H20.
Increased convection getting to some decent high altitude.. I assume


For starters
From this link

http://www.gse-promote.org/gallery/o3hole/o3hole.html

scroll down and find ...Movie


The animated movie of the 2002 event is absolutely sensational

Go to this movie link.

You will see the stratospheric anomalies around the sub polar region warm first and the warming becomes quite extensive around the pole until it is so intense the polar vortex splits in two..
Now .In the 2002 event ,the split in vortex ( twin vortex)
occurred in October. The warming around the polar vortex at sub-polar latitudes would have happened first l assume. In what month of 2002 l am not sure.

However it does look like this is an initialisation of a significant SSW event.? in June??


watch the movie.
Splitting of polar vortex 2002. The only documented major SSW from the SH.
Notice the warm stratospheric anomaly south of the OZ mainland before the vortex split...

http://www.gse-promote.org/gallery/o3hole/o3hole.html




Notice how the stratosphere warmed in Oct 2002 from this graph from the same link provided

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#1197323 - 03/06/2013 20:12 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
Ah Yes CS22 . You can see a polar vortex split in late Oct/early November 2012 in this rather cool animation

Go to animations on this page linked below and select the 2012
Ozone hole and UV index 2012
MPEG file

http://www.temis.nl/protocols/o3hole/archive.php?lang=0

Thanks for that info..

EDIT
Hey. This is a really cool animated time series of ozone concentration globally since 1979

Shame you can't slow the animation. !
If it doesn't start. select refresh on your browser

http://www.temis.nl/protocols/o3hole/animation/o3_1978_2008.gif


Edited by crikey (03/06/2013 20:19)
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#1197695 - 05/06/2013 21:33 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
The area of stratospheric warming in question is still relatively small but expanding.
The sat'pic' shows a sub polar low but looks nothing out of the ordinary.
However , the MSLP under the SSW is far more impressive .
See image below

From a little reading l have done recently

It is thought the vertical motion upward(the initial wave or forcing upward)
is instigated as an anomalous wave in the troposphere.( bottom atmospheric layer)

The wave breaks into the stratosphere which is about 20-40km altitude. The heat from the surface layer pushes up into the stratosphere.

There is an expected downwelling of colder stratospheric air into the lower troposphere ( surface) but this article says there is a lag of ....30 to 100 days!!

quote

"
Preliminary results indicate that the timing of the downward response is controlled by (1) initial anomalies in the stratospheric polar vortex, and (2) by the initial strength of the lower stratospheric eddy drag. These two criteria are found to be sufficient to predict the surface response of the stratosphere-troposphere system 30 to 100 days after application of the forcing."

Stratosphere-Troposphere Coupling
http://www.inscc.utah.edu/~reichler/research/projects/TS/TS.shtml

So, will watch the outcome for awhile

The SSW anomaly was over the southern Bight area on 1st June.

As these SSW's are often associated with a deep low at the surface layer . A look at the MSLP tonight indicates a very deep low at the surface near our SSW.

Here it is in play currently



Leading up to this event it should be noted
There were significant warm anomalies at the Antarctic surface of positive 10 in May 2013 . The month before the event.
( BOM global analysis anomalies)

The wave came from the Antarctic circle initially

The deep ,large low pressure of 956 hpa has only developed underneath the stratospheric warming recently ..4th June2013

Here is the surface low ,with two large highs flanking the anomaly on either side.

ACCESS G is showing some atmospheric anomalies near the region atm.
Which l may snap tomorrow

lots of time. I expect?

EDIT

There is a deep Polar fetch on the western flank of that low that should advect some very cold air toward the Bight and southern ocean in coming days?
Hopefully cool 'tassie' for you H20


Edited by crikey (05/06/2013 21:36)
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#1197893 - 06/06/2013 21:38 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
After doing some reading on this developing upper air warm anomaly. I have found the dynamics quite complex.
However a few brief thoughts from the research paper
Temperature Trend Patterns in Southern Hemisphere High Latitudes: Novel Indicators of Stratospheric Change
PU LIN AND QIANG FU et al 2009

These warmings typically occur later in winter around July-October as a seasonal anomaly but this warming event underway seems a few months early??

A strengthening Brewer Dobson circulation(BDC) is synonymous with warm Polar stratospheric anomalies

Particular warm spatial SST patterns in the tropics can create warm stratospheric polar anomalies

As polar vortex weakens toward summer in October, the planetary waves are more able overrun the force of a strong polar vortex and upwelling and vorticity into the stratosphere is more likely. An SSW event

The Antarctic south of the Australian mainland is a known area for the development of standing wave no 1,asociated with warm stratospheric anomalies in spring ( not in JUNE???)
----------------
So far l am not convinced this anomaly is consistent with a seasonal warming change commonly seen in spring!!
also
not confident this is a SSW as it seems way too early in winter

Looks like a wave anomaly of some description but would not rule out an SSW underway,or even a shift in the polar vortex in time due to the current 'wave event' underway
-------------------

Some snaps of developing anomalies

Just linked as there are a few
enjoy.
sleep

You will need to select the zoom button

Global synoptic and gradient winds _ACCESS

https://picasaweb.google.com/104698633266954768357/WindAnalysisAustralia#5885970093238458978

200hPa global thickness and 200hPa winds
https://picasaweb.google.com/104698633266954768357/WindAnalysisAustralia#5885972290252573698

850 hPa height and winds_global ACCESS
https://picasaweb.google.com/104698633266954768357/WindAnalysisAustralia#5885974966913246978



Edited by crikey (06/06/2013 21:39)
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#1197988 - 07/06/2013 15:51 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Locke Offline
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Registered: 27/12/2007
Posts: 4361
Loc: Brisbane
Following the SSW in the NH in January we saw temps plunge there. Could a ireasonably assume we might see the same occur for the currently occurring SH event?

Is this an indication that a month from now we might see a bitterly cold SH winter descend?
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#1198011 - 07/06/2013 20:04 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Posts: 2586
Loc: Tweed Heads
I think the incidence of cold outbreaks in mid Laltitude northern hemisphere attributed to SSW, Locke, is probably related to the increased incidence of them ,rather than one SSW event on its own.

The NH typically had a regular pattern of singular major SSW events in winter that timed and behaved according to the QBO phase (the upper wind regime over the equator).
Over the past decade this this pattern changed substantially and the SSW events have became more frequent and independent of the QBO oscillation.

Suggesting climate shift and changes to atmospheric circulation and chemistry?

SSW major events in the SH Antarctic stratosphere have been rare. But we may see more with solar downturn??

I would think that this is one of the keys to the cold outbreaks and changing Jetstream in the NH and maybe for the SH in the future?

A major SSW event changes the wind anomaly to easterly (opposite)in the area of the warming stratosphere and interrupts the Jetstream flow by 'drag'
This would create meanders or anomalies.
However the interruption is short lived .

I think the NH have been having multiple SSW's biennially.

If the climate is to cool re: solar downturn , we would expect to see changes in the climate variables that amplify to produce the reduced temperature.

So far in 2013 , the SAM (Antarctic)has been very positive keeping the cold locked in around the polar vortex with a strong contracted westerly belt.

SSW can warm the polar stratosphere and weaken the polar vortex, shift the SAM into negative and get the polar jet meandering and the westerly belt expanding onto the OZ mainland

My thoughts re : cold outbreak is that we would need more than one SSW event.

2002 was a year of average snow depth at spencer creek.
But it was also not a La nina ,neg IOD year as we may have in winter 2013 .. a different base

So lets see what happens..

As you know LOCKE. If we are to have a major solar minimum, we should expect some dramatic changes to our atmospheric circulation and climate variables.. The increase of SSW events may be symptomatic of a changing climate into a cooler phase?

Here is a link to a forum that 'follows' SSW events in the NH

Amazing detail discussed here

SUDDEN STRATOSPHERIC WARMING (Watch 2012-2013) http://www.boards.ie/vbulletin/showthread.php?t=2056803618

and a few bits of reading

http://www.theregister.co.uk/2012/09/24/stratosphere_events_affect_oceans/

-----------
Solar quiet spell like the one now looming cooled climate in the past
http://www.theregister.co.uk/2012/05/08/climate_is_affected_by_the_sun/

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#1207517 - 17/08/2013 18:53 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
Another Stratospheric warming event in our quadrant of the southern hemisphere. Same position as the last one

Information and my personal notes on this event here.

http://weathercycles.wordpress.com/2013/...re-august-2013/



Edited by crikey (17/08/2013 18:54)
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#1207790 - 20/08/2013 13:42 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
Interesting posts there Crikey. Keep up your good work!

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#1207800 - 20/08/2013 15:32 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
KevD Offline
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Registered: 23/09/2001
Posts: 5079
Loc: Bellingen NSW 2454
Indeed and sorry for not echoing that feedback earlier - was great to read your thoughts - wonder if there is a connection with the SAM?

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#1207807 - 20/08/2013 16:23 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Seira Offline
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Registered: 27/08/2003
Posts: 7166
Loc: Adelaide Hills.
There is apparently a 3-trough pattern (unfortunately no references) which is situated in the Southern Ocean which rotates slowly on a month/yearly (?) basis at those latitudes. Can't be sure of it, but may be a possibility smile .

Also, I wasn't sure some time ago whether this would be relevant, but it looked like a signal of some kind (SSWs?) showed up in the tropopause temperatures on the GFS obs page.


Edited by -Cosmic- (naz) (20/08/2013 16:28)

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#1207825 - 20/08/2013 19:00 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
BELLO BOY

The coincidence between the SAM/AAO going strongly negative since JULY and dropping 6.4 !! index point and the timing of the stratospheric warming event certainly indicates a strong connection l would have thought..

I read sunny days report for this time period of last week July and she has noted a quiet sun at this time period

This is however speculative but worth following ..

The most accepted cause l believe is some sort of anomalous atmospheric wave at the surface layer

I have noted that the westerly belt has been very wide during this SSW.

One of the experts on these things is Karin Labitzke.
http://strat-www.met.fu-berlin.de/labitzke/

Wil be interesting to see how SAM rends for the rest of the year as SAM has been incredibly positive up until late july

------------

Thanks for the feedback BD
-----------------

Cosmic . Yes. I have read a little about various standing wave patterns / numbers in the SH .

The annular wave..caused by the earths rotation creates nodes/waves associated with troughing in the southern latitudes

and in the climate threads somewhere ROM posted articles on the Antartic circumpolar current and moving SST patterns

Ian Wilson has recently completed some research into the link between planetary motion and the standing ..4 wave phase

quote" N=4 standing wave-like patterns in the summer (DJF) mean sea level pressure (MSLP) and sea-surface temperature (SST) anomaly maps of the Southern Hemisphere between 1947 and 1994."

I haven't read this yet but it is on my list.
http://tallbloke.wordpress.com/2013/08/0...ern-hemisphere/



SSW are far more frequent in the NH winter and rarer in the SH

Difficult to find information on these events in the SH

If we have a decent cold front..Maybe Check the stratospheric temperature spatial patterns .

Glad there is some interest

I did another article on the continuing emerging consequences of this last SSW

I by chance noted that NOAA's total ozone map also picked up this event and recorded a very noticeable increase in OZONE in the region as a result of the SSW

Now l have not read extensively on 0zone . But have have read enough to note there are some contradictions in the function and fornmation of ozone

I made a note of this ozone anomaly which surprised me

Ozone is meant to be produced in cold not warmer temps?

Yet ozone was produced in this warm anomaly

I raised this question on my blog ..regarding most likely my lack of expertise in the area.LOL
http://weathercycles.wordpress.com/2013/08/18/ozone/



http://weathercycles.wordpress.com/2013/...re-august-2013/









Edited by crikey (20/08/2013 19:07)
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#1207828 - 20/08/2013 19:34 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
Say Crikey how did you fine that image of ozone above I have gone to the site and some very good stuff there but I cannot find that one?

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#1207830 - 20/08/2013 20:00 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
I found it after a long search thanks Crikey!

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#1207831 - 20/08/2013 20:01 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA

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#1207832 - 20/08/2013 20:04 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
I cant seem to make anim run on my computer! what free program software do I need anyone please?

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#1207837 - 20/08/2013 20:26 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
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Looked back in time, crikey, some sort of connection between AAO and Ozone though hard to pin down just looking at both, looks good at times other times hard to see really!? Would need to look a lot longer to confirm or deny the connections.

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#1208133 - 23/08/2013 20:12 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
The 10hpa has progressed into a strong meridonal or wavy formation
as seen on this fabulous !!! animation of this SWELL!! smile
THe animation below is hotlinked and will update
You can clearly see the waves developing like an ocean swell!


source
http://www.cpc.ncep.noaa.gov/products/intraseasonal/temp10anim.shtml

I am keeping track of
this on my blog and posted this in comments tonight

Probably worthwhile noting that 10 hPa is the approx. the QBO layer . Wonder if there is a phase change underway in the QBO?

west to east phase or vice versa?

19th August 2013 animation...
"The saga continues.. The 10hPa layer in the stratosphere appears to be developing quite a wavy pattern of peaks and troughs on the animation.
The 10hPa has developed a strong meridonal flow
Of note ..
The troughs appears to be warm and the ridges appear to be cool."

It will be interesting to see if this wave action transfers to the 200hPajetstream and then down to long wave meridonal troughing at the surface layer at some time soon?


http://weathercycles.wordpress.com/2013/...re-august-2013/
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#1208139 - 23/08/2013 21:19 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
Looking at the current 200hPa stratospheric anomalies. There does look to be a massive positive height anomaly right around the Antartic stratosphere
see snaps below

Wonder whats going on?

Warming is stratosphere.More height?

Warming in troposphere..or surface of Antartica?


Something is changing the dynamics here quite significantly

Here is the before (JULY 2013) and now (AUGUST 2013)snaps

Impressive change isn't it!



Spring could be interesting with disruptions to the Jetstream flow?
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#1208160 - 24/08/2013 08:43 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
Looks like it went downwards quite quickly Locke lookin at 500hpa heights 60-90S anoms Thw whole warming I mean. Strange that as per the last time it only seems to affect the eastrn 2/3rds globe(as on the chart) and have a gap of reasonable size along the west longtitudes near south america. Maybe something to do with the standing wave over the s americian andes range which goes well south and disrupts the westerly flow?


Edited by bd bucketingdown (24/08/2013 08:47)

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#1208163 - 24/08/2013 09:00 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
Howeever does not show up much further north at 45S to 60S
looks like Rossby Waves there at 45 to 60S!
PS By the way Crikey my computer does not work on those animations do you know of a software program that I may be missing to fix that?


Edited by bd bucketingdown (24/08/2013 09:07)

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#1208181 - 24/08/2013 15:35 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Chris Stumer Offline
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Registered: 28/01/2010
Posts: 1611
Loc: Kingaroy
what what it mean if we had disruptions to the jet stream flow in Spring?

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#1208194 - 24/08/2013 21:55 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
Posts: 2586
Loc: Tweed Heads
What the!!
A massive atmospheric sinkhole has developed at 10hPa over Antartica.
That means the upper air is collapsing down over Antartica.
THis would push air up around the 'well' ?

Atmospheric Height low over Antartica and high around southern ocean.?

Have a look at the this snap below . The symmetry is incredible. That really is a sink hole.

This is the QBO layer. The QBO is currently westerly and strengthened to 14.4 last month

What the!!!

Central height - 25000 at the sth pole
Outer closed height bar is 30800.
A difference in height of = 5800




Thanks for your interest and analysis tools BD. Good to have some archives

Chris my thoughts on the implications of this sinkhole.
The collapse of the air layer over the Antartic is a significant perturbation.

A possible suitable analogy might be if someone cooled the air drastically over the affected region. The air depth has shrunk

or

as if someone has dropped a weight in the centre and squashed and displaced the air ?

Either way there should be some changes in the vertical and horizontal wave patterns in the southern hemisphere.

Extreme geopotential height gradients.
This should affect all atmospheric layers

Some thoughts
SAM could swing wildly?
Extreme anomalies in atmospheric pressure. High and low pressure?
Jetstream anomalies
Increased winds?
Fast changing synoptic patterns
The mind boggles

Spring could be dynamic!!!?

If you find anything BD.. Please post..
Great weather watch this one.

or is this just a change of season phenomena?
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#1208196 - 24/08/2013 22:05 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
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Loc: Tweed Heads
BD.
Re: the animation
The file is a .gif

You may have change your browser settings to allow .gif's

http://www.cpc.ncep.noaa.gov/products/intraseasonal/z200anim.gif
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#1208205 - 25/08/2013 07:49 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Loc: Eastern A/Hills SA
I can read all gif files except the animationn does not work stays on first pic always and does not move. I think I need a software file that somehow got deleted from the computer as I used to be able to read them Crikey. Will have to ask to computer wizz son I think!

That looks like a meteorological black hole there will have to look and see, never really looked at 10hpa charts previously to this?!

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#1208206 - 25/08/2013 08:01 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Looking at the 10hpa temps and thinking maybe this is what they look like every early spring crikey, strong temp gradients, strong westerly jets, fast moving fronts? IE may be quite normal in reality, just we have not looked up that high ussually. Just thinking aloud! cheers


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#1208210 - 25/08/2013 09:02 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Chris Stumer Offline
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Registered: 28/01/2010
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It will be interesting to see this will affect our storm season, this could also why we've been having big changes in temperature lately, a week or so ago it felt like late September and within a day or so the temperature dropped like a rock.


Edited by Chris Stumer (25/08/2013 09:08)
Edit Reason: more infro

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#1208215 - 25/08/2013 10:07 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Mad Elf #1.5 Offline
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Registered: 05/03/2012
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Loc: Mt Hallen QLD
Earlier posts suggest SSW happening a few months ago, would that have caused all that nasty cold weather in Tassie & N.Z early august?
If so, would this extreme depression herald another bad cold snap end of next month for Tassie & N.Z? I'll be in Auckland end sept with son#2 playing league, hopefully NOT in snow!

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#1208242 - 25/08/2013 19:00 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Hey BD. That's a nice symmetric temperature pattern of the 100hPa temp you have snapped there.
That warm donut area anomaly is at the Jetstream level ...Interesting to see how this will pan out..

The temperature pattern is as you would intuitively expect.
The air sinks in the centre of hole
The sinking air has to go some where so radially pushes air up around the periphery of the hole.
Warm air from surface pushed up to higher layers at the 100hPa layer around the southern ocean in a donut shape . If strong enough the uplift penetrates up into the upper stratosphere to create some stratospheric warming spots.

This warmer air has entered the Jetstream layer
The effect may be surprising as jetstreams are formed from strong temperature differentials between sub tropical and sub polar 200hPa air.
If the temperature gradient increases as it currently appears
In theory the jet should increase speed and become more zonal.
THat would cause less fronts? As the Jetstream is straighter.

However the complex dynamics of waves , horizontal or vertical in this situation may create a mixed response?

Not sureMad elf re: the consequences. As BD says we rarely monitor the upper stratosphere . So some new territory in some respects

I will say BD. I have had some discussions with REN on Tallbloke blog who seems to believe this is quite extraordinary.


BD do you have a map of MSLP over the SH atm
With air descending strongly. The pressure over the Arctic should be anomalously high and the pressure over southern ocean rising should be anomalously low..

Maybe cold air from the Antarctic will be pushed northward as the air descends?
--------------------------

I have been updating my notes on my research blog daily on this event
Here are some notes from your post l posted tonight in the comments section

----------------------------------
Some continuing developments. Thanks to BD at weatherzone for his observations and snaps which will include below.
http://forum.weatherzone.com.au/ubbthrea...min#Post1208215

AUGUST 24th 2013
Some strong crests and troughs circulating around the south pole. A SSW appears to be orbiting the sth pole currently and on the 24th Aug 2013 is located of the southern African post as seen in snap below

10hP temperature
Central cold spot is minus - 85 deg C
Centre of hot spot (SWW) is minus 30 deg c

The temperature difference along that line is a massive 55 deg C

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/gif_files/gfs_t10_sh_f00.gif

----------------------------------------------------------------

The 100hPa layer on the 24th August 2013
-Cold core around the south pole
-warm anomaly in a donut configuration around the southern pole at southern ocean latitudes. The warmer and cooler patches around this donut shape are suggestive of a wave pattern within the donut shape

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat_a_f/gif_files/gfs_t100_sh_f00.gif


EDIT
Also note .. There was a strong solar storm recently that sent the cosmic ray flux dropping drastically.
Some sought of pressure collapse ?
REN seems to see a top down response


Edited by crikey (25/08/2013 19:02)
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#1208245 - 25/08/2013 19:30 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Mad Elf #1.5 Offline
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Interesting stuff crikey! Anyone have any historical facts of the lowest measured mslp depression marching past tassie & N.Z. ?
Keep up the good work crikey.

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#1208247 - 25/08/2013 21:13 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Petros Offline
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Registered: 30/12/2002
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you really are a diligent researcher Crickey - pls keep up the good work, the concepts of this thread (esp the warm area down S uppers) is hard for this ole dummy to keep up with!

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#1208251 - 25/08/2013 21:27 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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"BD do you have a map of MSLP over the SH atm
With air descending strongly. The pressure over the Arctic should be anomalously high and the pressure over southern ocean rising should be anomalously low.."(Crikey)
The BOM CHARTS below give a good idea at what is going on at the surface...strong lows in the westerlies, yes, and high over Antartic area, though this is what normally occurs at this near early Spring time of year, though would not be sure of whether they are normally this low, the low pressure centres I mean.


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#1208253 - 25/08/2013 21:30 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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This is the 1000-500 thickness southern hemp view, comments same as previous post...

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#1208255 - 25/08/2013 21:32 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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200 height looks like this!

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#1208256 - 25/08/2013 21:36 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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This the pressure anom for July 2013...but does not come up as an ftp file it is unfortunately! Sorry yes it now does come up!lol!


Edited by bd bucketingdown (25/08/2013 21:43)

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#1208257 - 25/08/2013 21:40 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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Loc: Eastern A/Hills SA
And here is 200hpa height for July 2013.
Enough info overload for you there, Crikey! smile


Edited by bd bucketingdown (25/08/2013 21:40)

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#1208258 - 25/08/2013 21:43 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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There was a tight gradient of height there for July at 200hpa
from lowest colour min to almost the highest colour max!

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#1208262 - 25/08/2013 22:05 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Those last 2 charts have vanished, but can be found on BOM site!

been plenty of solar flares around as big or much bigger than any recent one as we are at solar max albiet a weak cycle 24

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#1208315 - 26/08/2013 18:44 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
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A few more snaps of the AUGUST 2013 Upper air anomalies ...
Met office global satellite picture indicating an intense low near the latest SWW hot spot south of sth Africa
25th Aug 2013


24th Aug 2013
and a snap of the significant increase in ozone in the donut around the south pole. This is rising air and warming stratosphere
SWW create more ozone?
Notice the decline in ozone where the air is sinking over the south pole and is cooling


Jetstream raised near the SWW currently sth of sth Africa
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#1208730 - 31/08/2013 17:56 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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NERD 65 has reported a deep southern ocean on another thread.
http://forum.weatherzone.com.au/ubbthreads.php/topics/1208689/Deep_Southern_Ocean_Low#Post1208689
I had a look at the upper stratosphere 10hPa and there is continuing atmospheric waves orbiting around the south pole.
Geopotential height anomalies consistent with those strong vertical wave patterns

This action seems to be creating warm stratospheric anomalies at the crest of the waves.
Here is a snap of the 25 th Aug. 2013

Underneath these warm stratospheric warmings are areas of intense low pressure and underneath the troughs of these waves is anomalous blobs of high pressure at the troughs of these waves



source
http://www.bom.gov.au/australia/charts/indian_ocean.shtml



-----------------------------------------

I also came across this information which confirms the anomalous shrinking of atmosphere over the south pole and the associated anomalous high surface pressure

This is the affect at the surface
........
Found some implications of the increased high pressure over the Antartic circle

Quote:”Antarctic sea ice extent for August 19 is 18.70 million square kilometers (7.22 million square miles), a record or near-record high level (August 19, 2010 was similarly high), led by unusually extensive ice in the Bellingshausen, Amundsen, and Ross seas, and in the western Indian Ocean sector.
Climate conditions since June have been variable,
but the most recent surge in ice growth has occurred during a period of unusually high pressure over the center of the continent,

resulting in a slowing of the circumpolar winds,

warm winter conditions for the central ice sheet areas (Vostok Station and Amundsen-Scott South Pole Station both had periods of spring-like -30s earlier in the month),


and cold conditions in the Bellingshausen, allowing ice to grow extensively there.”

source
http://forum.netweather.tv/topic/76273-arctic-ice-discussion-2013-melt-season/page-33
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#1209658 - 09/09/2013 22:38 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
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An amazing Report of record swings of temperature extremes in Sth America.
On August 29th the temperature soared to 32.6°C (90.7°F) at Bahia Blanca, Argentina, an all-time record for the month of August. This follows a reading of -7.9°C (17.8°F) recorded on August 25th, their all-time record low for the month!
The site has a POR (period of record) of over 100 years. Their normal daily range of temperature during August is 9.2°C-16.0°C (49°F-61°F).
http://www.wunderground.com/blog/weatherhistorian/comment.html?entrynum=189
Looks as though the events in the stratosphere are linked. THe article showa the anomalies of 500mb geopotential height.
The atmospheric waves continue around Antartica
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#1209739 - 10/09/2013 21:23 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
stormy_bec Offline
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Registered: 05/11/2009
Posts: 328
Loc: Kimberley Station Qld
I'm finding this thread very fascinating. Keep it coming crikey.

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#1212581 - 04/10/2013 21:16 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Hey.. Glad you are following stormy-bec!
Still lots of action in the SH 10hPa layer. BIG waves! still
Appears to be a standing pattern currently with the same height anomalies persisting in the same regions((se the animation in the above post)
They don't appear to be rotating around the south pole like they were in the earlier months.

Currently the 200hPa jet stream is very wavy/meridonal.
The sub-tropical jet next Wednesday the 9th oct 2013 will dip as low as the TASMANIAN LATITUDE!!
I have never seen the sub-tropical jet that far south!!

This will be accompanies with a large high pressure cell seated in the trough of the sub-tropical jet!! centred as far north as Brisbane!! with some severe troughing to the east in the coral sea near the Islands once again.
This surface high is likely to bring anomalously warm winds from the anomalously hot interior down southward across SA and VIC and maybe 'Tassie' this week..Approx' 8th/9th oct2013

Here is a snap of the sub-tropical jet well south!! on the 9th Oct2013



source
http://www.bom.gov.au/australia/charts/v...it=Refresh+View
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#1212664 - 06/10/2013 08:52 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
MOUNTAIN h2o Offline
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Registered: 23/03/2012
Posts: 682
Loc: Hobart Lenah Valley Tas 198 as...
Hey Crikey , spot on with your prediction and forecast. Hobart on Wednesday forecast for 24 degrees !! 7 over average , but after 23 here yesterday I would say it's a good chance of being much warmer.
Will be interesting for sure.

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#1213687 - 15/10/2013 13:30 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW
Originally Posted By: crikey
An amazing Report of record swings of temperature extremes in Sth America.
On August 29th the temperature soared to 32.6°C (90.7°F) at Bahia Blanca, Argentina, an all-time record for the month of August. This follows a reading of -7.9°C (17.8°F) recorded on August 25th, their all-time record low for the month!
The site has a POR (period of record) of over 100 years. Their normal daily range of temperature during August is 9.2°C-16.0°C (49°F-61°F).
http://www.wunderground.com/blog/weatherhistorian/comment.html?entrynum=189
Looks as though the events in the stratosphere are linked. THe article showa the anomalies of 500mb geopotential height.
The atmospheric waves continue around Antartica


It looks as if the current SSW was retrograding around the 7th/8th of this month, is that normal behaviour for these events?

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#1215703 - 29/10/2013 20:30 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Sorry CS22.. I missed your comment on the 15thOct

CS22 said
'It looks as if the current SSW was retrograding around the 7th/8th of this month, is that normal behaviour for these events?

Hi ..Just dropped in for a 'raincheck' on the current animation

Yes, CS. Looks like the wave pattern has subsided. Just looks like some residual 'sloshing about' as the wave amplitude subsides
I guess this is 'normal' as SSW waves are a winter phenomena
as far as l understand

Noting the 14th October 2013 ..The wave has gone..and a zonal flat lake looking image remains

I think the red ( warm anomaly) will weaken as summer deepens)
Notice the SSW cranking up in the NH as it should for their winter.

There is a nice warm anomaly emerging in the NH at 120E currently

Strong surface lows are often synonymous with SSW as far as l have noticed so far.. I think the rising / expanding warming anomalies creates a wave effect or disturbance

The sun is moving away from the Northern hemisphere and l think the days are shortening in the Arctic and cold on the surface increases

Looking at the animation. Looks like a period of transition from SH to NH , in terms of SSW activity. ( end of October in 2013)
regards

PS
If you want to follow the NH SSW events
Here is a great UK thread.. dedicated to SSW's

http://forum.netweather.tv/topic/78161-stratosphere-temperature-watch-20132014/page-8


Edited by crikey (29/10/2013 20:30)
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#1216930 - 07/11/2013 22:58 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
KevD Offline
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Registered: 23/09/2001
Posts: 5079
Loc: Bellingen NSW 2454
Worth quoting the post below at this time - just watch how the the warming fades away to nothing before popping up again to the SW of Australia. Interesting to watch how these changes tie in with the SAM - would love to be able to explain it away but way above my head. Instead just watching the patterns and learning slowly.

Originally Posted By: crikey
An amazing Report of record swings of temperature extremes in Sth America.
On August 29th the temperature soared to 32.6°C (90.7°F) at Bahia Blanca, Argentina, an all-time record for the month of August. This follows a reading of -7.9°C (17.8°F) recorded on August 25th, their all-time record low for the month!
The site has a POR (period of record) of over 100 years. Their normal daily range of temperature during August is 9.2°C-16.0°C (49°F-61°F).
http://www.wunderground.com/blog/weatherhistorian/comment.html?entrynum=189
Looks as though the events in the stratosphere are linked. THe article showa the anomalies of 500mb geopotential height.
The atmospheric waves continue around Antartica




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#1223310 - 02/12/2013 11:03 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW
Is there such a thing as a Stratospheric Cooling event? Reason being 10hpa temps look very cold at the moment in both SH and NH, or is this what we consider normal?

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#1223325 - 02/12/2013 13:37 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
No such thing that I have ever heard of CS in my long career, and googling it produced zip also!

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#1223331 - 02/12/2013 14:21 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW
Thanks BD. I also could not find anything on Google, hence why I thought I'd ask. smile

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#1223355 - 02/12/2013 17:03 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
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CS22 and BD..There are stratospheric temperature anomaly time series to view for some comparison with the long term mean

Here is a link
http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/

Yes it does appear to be cooling generally across the board CS22. Nice observation

As an example from their latitude menu
This time series anomaly graph below confirms cooling below the mean for the NH between latitudes 90-65N at 10Hpa layer ( upper stratosphere)
and is occurring at all latitudes from what l could deduce

( hot linked and will update)
source link
http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/10mbnhlo.gif


Interesting to note from the above graph that this time last year there was a cold dip toward the coldest anomalies from OCT 2012 to April 2013
I suppose you could argue that this was a stratospheric cooling event in general.
Notice also the NH SSW that occured in the depths of the strong cooling anomaly last January ( NH winter)

Perhaps a repeat of last year emerging?

Something to observe here.. grin


Edited by crikey (02/12/2013 17:06)
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#1223362 - 02/12/2013 17:57 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
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Could be Crikey! Will be interesting to watch and see what eventuates.

Below is a bit of a write up(without his fancy charts) from Joe D'Aleo on this very subject that you might find interesting.

Will a stratospheric warming take place again this winter?

November 25 06:48 PM

We know the AO and NAO play a key role in the Northern Hemisphere winters. A negative AO/NAO is associated with polar high pressure and upper level warming that causes cold air to push south into mid latitude continents.

Often a collapse of the AO/NAO is precipitated by what is called a stratospheric warming. See the one that developed in late December last year. It took a while to have a major impact on the weather as the pressure rises did not reach the critical 500mb level mid troposphere right away in any significant way. It really was late winter and spring that did and the late major blizzards of the late winter and spring resulted.

The SSWs begin with a bubble rising into the stratosphere in South Central Asia that starts a disruption and sinking into the polar region. See also how it affected UK in similar fashion with collapsing AO spikes tied to UK cold periods.

A very good description of the phenomena and the causes by a television producer by day, who as a hobby, studied climate and weather nights and weekends for over 30 years (here).

The classic high latitude stratwarms/blocking of course was the 2009/10 winter when two pulses took place and dominated the entire winter. I wrote about it early in November that year here.

The general rule has been the westerly QBO at solar max and east at solar min had a tendency for SSWs but in the long solar minimum of recent years, it did not seem to matter with warmings and blocking almost every winter.

The 2010/11 winters started blocky out of the box and had rebound warmings in the mid trop near 500mb in early February when a major snowstorm occurred.

It has been cold in the arctic so far with a positive AO. The animation that follows shows a warming in the North Atlantic/arctic. No sign yet of a south central Asia disruption beginning. As the animation above showed, it moves very fast once it begins. The descent back down into the troposphere may lag weeks.

With the sun near a solar max (not a great one) and the winds westerly throughout the stratosphere, one might expect one to occur this winter. The other solar max year in a relatively weak cycle with a similar west QBO was 1969/70.

Much more to come.

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#1223381 - 02/12/2013 20:53 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
A cold event always follows a warm event(SSW)I note In NH where they really get them SH events are fairly weak in comparison!
last years NH event follows...

About best I can find for SH is here 2002 below...

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#1223382 - 02/12/2013 20:57 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
N Hemp 2012

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#1223383 - 02/12/2013 20:59 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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Loc: Eastern A/Hills SA
S Hemp 2010 not a bad one there in 2010 followed by a cold burst!



Edited by bd bucketingdown (02/12/2013 21:00)

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#1223385 - 02/12/2013 21:05 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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Loc: Eastern A/Hills SA
Many years in S Hemp it is just a bit of a mess really!


and this year...

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#1223387 - 02/12/2013 21:08 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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Loc: Eastern A/Hills SA
These are for the whole hemispheres 60-90N N Hemp and 60-90S S Hemp, so won't show the area near Australia, England or wherever...just the whole hemispheres


Edited by bd bucketingdown (02/12/2013 21:08)

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#1224549 - 10/12/2013 20:52 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Registered: 01/02/2011
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Loc: Tweed Heads
There is an intense surface low forecast to ramp up in the sub polar nth Pacific next week around 16th dec2013
If these things get big enough ( the wind speed gets a purple coloring 80-100knots) these lows can initiate a significant SSW

Could be an interesting watch
Probably still a little early as not in the depths of winter yet


source link
http://www.bom.gov.au/australia/charts/v...it=Refresh+View

Note the cyclone in central Indian ocean next week curently developing now near equator on southern H side
------------------

THanks BD for those stratosphere profiles smile



Edited by crikey (10/12/2013 21:00)
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#1224613 - 11/12/2013 13:24 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
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Loc: Lane Cove, Sydney, NSW
Very interesting Crikey.

The boys over at Weather Bell have also been hinting at the possibility of SSW in the coming weeks.

Something to keep an eye on anyway.

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#1224618 - 11/12/2013 14:08 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
Last years SSW in N hemp was preceded by a cold surge of sorts same as is evident now


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#1240595 - 09/02/2014 11:36 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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Loc: Eastern A/Hills SA
I posted your page on WUWT Crikey as it looked so similar to the NH event shown on their thread Cheers Ian(BD)
http://wattsupwiththat.com/2014/02/08/wh...ex/#more-102862
http://weathercycles.wordpress.com/2013/...-1/#comment-309


Edited by bd bucketingdown (09/02/2014 11:37)

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#1263033 - 08/05/2014 21:30 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Is that southern hemisphere SSW developing south of Aus??



source
http://www.cpc.ncep.noaa.gov/products/intraseasonal/temp10anim.shtml

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#1263041 - 09/05/2014 07:25 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Loc: Eastern A/Hills SA
Good spotting CS, needs to be watched!
cheers

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#1263042 - 09/05/2014 07:53 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Interestingly(see previous page for CS post re-SWW Loop, and past few posts also)
on that loop hot spot in NH which shows first on the loop corresponds to this warm temp anomaly shown in central-east Russia-North China area

and
also interestingly, my own models have been forecasting a warmer drier spell for SE australia for several weeks now, lasting for 2 to 3 weeks starting from next week onwards
cheers


Edited by bd bucketingdown (09/05/2014 08:03)

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#1263096 - 09/05/2014 16:34 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Nice obs' CS22.!! Yes that is a nice area of SSW developing in the SAME place/longitude as last year. You would expect some nice wave activity to evolve from this disturbance
You can see the colder anomaly on the eastern side
This because this is a wave disturbance. Hot and cold anomalies adjacent
Taken a snap of that
This should get the Jetstream wavy/ meridonal as time goes on and a decent dip into -neg for the SAM

5th May 2014



and the question is . What has started this warm anomaly
Some researchers suggest strong lows underneath in the stratosphere. Some say ozone changes in the stratosphere
Could be other things

Hope to go looking
Here is the ozone anomaly time series

http://www.cpc.ncep.noaa.gov/products/CDB/Extratropics/figs5.gif
for a start. Haven't really looked in detail here so no idea really. At this stage
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#1263098 - 09/05/2014 17:06 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Current SH MSLP showing some very strong low pressure belt at 60s currently
You can see a pair of strong sub polar cyclones siting under he warm stratospheric anomaly, raising air into the stratosphere via a convective vortex perhaps



Quite amazing how the stratospheric temps change dramatically at this time of the year.( swing bi-polar see saw April/early May)
Its our turn now.. Bring on winter wonderland. says me hopefully

The fronts were not particularly good last year
But last weeks awesome cold front could be a good start for 2014.
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#1263103 - 09/05/2014 19:29 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Petros Offline
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Crikey, wouldn't a warm anomaly SW of Vic create a period of "less intensive" fronts while that anomaly is present?

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#1263129 - 10/05/2014 09:07 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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"SSW's alter the tropospheric circulation through a process called potential vorticity thinking (pretty odd, I know). PVT essentially acts like a thermal wind adjustment. During an SSW, changes to the stratospheric polar vortex in the lower stratosphere cause an imbalance. Generally speaking, when a flow is out of balance, the adjustment process ripples to regions relatively far from the location where the imbalance occurs. In this case, when there is an imbalance in the lower stratosphere, the adjustment extends all the way down to the earth's surface. Indeed, the adjustment "excites" the negative phase of the Northern Annular Mode (also known as the Arctic Oscillation) and the negative phase of the North Atlantic Oscillation. In turn, this "excitation" can pave the way for an outbreak of cold air over the Northeast States"http://www.wunderground.com/blog/24hourprof/sudden-stratospheric-warmings-ssws

Note bold, SSW's work way down to surface often, not the other way around, so the effects of the SSW are likely still to be felt, in this case as high pressure not low pressure I would expect anyway by instinct!

Also below from same source...
SSW's were discovered over Berlin in the early 1950s (the good old days). Subsequent research indicated that upward-propagating, planetary-scale Rossby waves transported energy and momentum into the stratosphere. Without getting into too much atmospheric physics, upward-propagating Rossby waves produce a meridional transverse circulation in the stratosphere, with sinking air over high latitudes and rising air closer to the equator. The dramatic compressional warming associated with the subsidence over high latitudes is the hallmark of SSW's that I mentioned earlier. As you can imagine, dramatic warming in the region of the polar vortex upsets the circulation in the stratosphere. As the normal north-south temperature gradient breaks down, winds associated with the polar-night jet weaken (thermal wind arguments) and sometimes reverse (become easterly). If stratospheric winds at this level become easterly, further upward transfer of wave energy is blocked, and the deceleration of westerly winds and subsidence warming work it way downward.


Edited by bd bucketingdown (10/05/2014 09:11)

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#1263149 - 10/05/2014 16:24 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Fascinating phenomenon. I'm a little cautious though-until I know more-about the stratospheric warming we are currently seeing as noted.

The cdas 10hPa area of temp anomaly posted by Crikey above after mid to late April(also reflected with 30 and 50 hPa anoms animations from same site),when it seems to intensify most, seems to have drifted marginally to the north. That may be why it does not appear in the graphic linked below (apologies having trouble getting the image to post at moment)- that is, there is no sign of the warming still being in the stratospheric polar vortex at present, even though there is anomolous warming in the stratosphere in an area bordering the vortex.

Even were the anomaly in the vortex, I'm not sure that it is significant enough to make it a factor in driving anomalies within the troposphere just yet.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/hgt.aao.shtml

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#1263152 - 10/05/2014 17:16 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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The warm anomaly is averaged out on that hemispherical chart by the cold anomaly to the east. and much of it is north of 60S also and is not shown on that chart Snowbaby.
It is quite significant and will affect the weather lower down and already is doing so on the progs with highs starting to dominate in the Australian region, and that feature is likely to continue to have affects for a couple to come yet at least I would suggest.
As I said earlier my models have forecast a drier, maybe warmer spell for SE Australia for many weeks now for this 2 to 3 week period ahead. So it fits in well imo anyway. We shall see how it develops...interesting!

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#1263157 - 10/05/2014 18:37 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Petros. Here is a visual animation 3D of how a massive uplift in air from a sub polar vortex(low) might punch through into the upper stratosphere (10mb)and how descending air might behave
Keep in mind this is a drum animation not a real life atmospheric video

source
http://www.upscale.utoronto.ca/PVB/Harrison/Vibrations/

The air punching through is warmer than the air at 10mb
note the upward phase of this standing wave action

You can see from the animation this disturbance also causes a downwelling of colder stratospheric air toward the surface ( troposphere)
The result of the volcanic' style explosion is riplesand waves in the atmosphere at all layers and longitudes as the wave action propagates
There are dips and troughs.
As to how this current SSW will affect Gippsland. This will be a good weather watch to take notes. LAST YEAR we had the same. What happened?

Snowbaby
Last year there was some effects from the wave action as the SAM went strongly negative about 2 weeks from the initiation of the SSW and subsequent wave activity around the sub polar region
Pages 1-3 of this thread cover last years event

Here is a snap of the first SSW last year .
29th May 2013


Note that this current SSW in the SAME location is 3 weeks e earlier!!!at 5th May 2014


Here is the effect on the AAO/SAM last year. You can see the SSW commenced around the 29th May and you can see the amplitude of the SAM commenced increasing about a week later
With the dips and troughs in SAM getting stronger in successive peaks and troughs 'Look at one of the larger dips in July to August!!
SSW sending the SAM into a higher energy wave pattern with increasing amplitude.
You would expect this to happen again.?









Edited by crikey (10/05/2014 18:40)
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#1263159 - 10/05/2014 18:57 Re: Stratospheric sudden warmings (SSWs) [Re: bd bucketingdown]
Petros Offline
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Originally Posted By: bd bucketingdown
"SSW's alter the tropospheric circulation through a process called potential vorticity thinking (pretty odd, I know). PVT essentially acts like a thermal wind adjustment. During an SSW, changes to the stratospheric polar vortex in the lower stratosphere cause an imbalance. Generally speaking, when a flow is out of balance, the adjustment process ripples to regions relatively far from the location where the imbalance occurs. In this case, when there is an imbalance in the lower stratosphere, the adjustment extends all the way down to the earth's surface. Indeed, the adjustment "excites" the negative phase of the Northern Annular Mode (also known as the Arctic Oscillation) and the negative phase of the North Atlantic Oscillation. In turn, this "excitation" can pave the way for an outbreak of cold air over the Northeast States"http://www.wunderground.com/blog/24hourprof/sudden-stratospheric-warmings-ssws

Note bold, SSW's work way down to surface often, not the other way around, so the effects of the SSW are likely still to be felt, in this case as high pressure not low pressure I would expect anyway by instinct!

Also below from same source...
SSW's were discovered over Berlin in the early 1950s (the good old days). Subsequent research indicated that upward-propagating, planetary-scale Rossby waves transported energy and momentum into the stratosphere. Without getting into too much atmospheric physics, upward-propagating Rossby waves produce a meridional transverse circulation in the stratosphere, with sinking air over high latitudes and rising air closer to the equator. The dramatic compressional warming associated with the subsidence over high latitudes is the hallmark of SSW's that I mentioned earlier. As you can imagine, dramatic warming in the region of the polar vortex upsets the circulation in the stratosphere. As the normal north-south temperature gradient breaks down, winds associated with the polar-night jet weaken (thermal wind arguments) and sometimes reverse (become easterly). If stratospheric winds at this level become easterly, further upward transfer of wave energy is blocked, and the deceleration of westerly winds and subsidence warming work it way downward.


Thanks, but must admit I didn't understand hardly a word of it. All the quotes relate to the Southern hemisphere?

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#1263160 - 10/05/2014 19:05 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Petros Offline
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Re....
Petros. Here is a visual animation 3D of how a massive uplift in air from a sub polar vortex(low) might punch through into the upper stratosphere (10mb)and how descending air might behave
Keep in mind this is a drum animation not a real life atmospheric video

source
http://www.upscale.utoronto.ca/PVB/Harrison/Vibrations/

The air punching through is warmer than the air at 10mb
note the upward phase of this standing wave action

I still don't get it, sorry to all posters above trying to help... If the uppers are warm, doesn't that make it harder for "massive uplift in air from a sub polar vortex(low) might punch through into the upper stratosphere (10mb)"???

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#1263166 - 10/05/2014 20:16 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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No worries Petros. some more info may help
Before the SSW event the uppers were cold( normal)(minus 70deg c) No capping ..

Suggesting the warm uplift is caused by a strong sub polar low that has no warm anomaly at the upper layer to cap it( inversion)
The warmer air (minus 38 deg c)pushes through the minus 70 deg c layer and spills over and down somewhat like a volcano. Displacing the colder air downward and outward

Mid latitude storms l believe can be capped from a warm upper air. So this is different

Just looking at some of those temps at the lower stratosphere layer 200hPa here curently

-------------------------
DIAGRAM below is lower stratosphere 200hpa below the 10hPaupper stratosphere

A warm anomaly in the SSW event at the 200hpa layer currently is minus -38 deg c

The cold anomaly tongues there on this map is minus 75 deg! c .Come DOWN from colder 10Hpa layer ( downwelling)


source
http://www.bom.gov.au/australia/charts/v...it=Refresh+View
-----------------------------------
Here is the temperatures for the 10hPa upper stratosphere layer
in the SH for 2014/2014

Notice the mean in December(summer in the SH) is minus 25 deg c
and
the mean 10hPa temp in the SH in July is minus 75 deg C

So the stratosphere naturally gets colder in winter

These SSW events are bubbles of warmer anomalies

So a bubble of air at minus 38 deg c in May is a significantly warm anomaly compared to the surrounding air

Here is the 10hPa upper stratosphere mean temps and the anomalies from 2013 into 2014

Nothing unusual here for may 2014 ..yet


source
http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/10mb6590.gif

In fact you can se that last years 2013 SSW bubble did not affect the overall mean 10 hPa Antarctic anomaly at all
It was an isolated event.
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#1263632 - 15/05/2014 07:23 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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My earlier post:
"Interestingly(see previous page for CS post re-SWW Loop, and past few posts also)
on that loop hot spot in NH which shows first on the loop corresponds to this warm temp anomaly shown in central-east Russia-North China area

and
also interestingly, my own models have been forecasting a warmer drier spell for SE australia for several weeks now, lasting for 2 to 3 weeks starting from next week onwards
cheers"

The result of SSW near Australia is this.......
"South Australia feeling the heat the most
Brett Dutschke, Wednesday May 14, 2014 - 14:50 EST

It may seem strange mentioning "heat" only a few weeks away from winter, but it is all relative - a late-autumn heatwave is developing and it is South Australia which will be feeling it the most, warming five-to-ten degrees above average.

This week has started in a warm way, at least in terms of day-time temperatures, warming a few degrees above average and it is only going to get warmer.

Maximum temperatures for the next seven-to-ten days will average five-to-seven degrees above the long-term norm across the state. Some centres will be as much as 10 degrees above average on some days.

If these anomalies occurred in summer it would mean temperatures reaching the mid-to-high 30s but at this time of year it means a relatively comfortable mid-to-high 20s.

A run of days in the mid-to-high 20s is very unusual for this time of year, it is more typical of April.

For some centres it will be the warmest week this late in the season since the 1950s. Adelaide will average a maximum of about 24 degrees and Ceduna about 27 degrees, making it the warmest week this late in the season since 1957, when heading into winter they averaged 24.5 and 27.3 degrees respectively.

Kyancutta is one of the best placed towns to beat the 1957 heat by averaging a maximum of more than 27 degrees, making it the warmest late-season week since 1934 when it averaged 28 in late May.

With days warming up this much, nights will also warm up, enough to keep frost away and significantly reduce the need for using heaters.

It is not all comforting news - the run of warmer-than-average days is largely due to clearer-than-normal skies and a lack of cold fronts which means we are also looking at an extended dry run. The warm, dry spell will lead to higher-than-normal evaporation, counteracting the recent rainfall and drying out dams and starving crops and gardens.

Evaporation will amount to as much as four-or-five millimetres per day in some areas, about twice the normal evaporation rate for this time of year, more typical of April, just like this week's temperatures.

The polar jetstream is now dipping south of mainland Australia after having just been a long way north and is leading to a "blocking" high over the Tasman Sea. As a result, cold fronts are now being forced south of mainland Australia, leaving skies fairly clear and winds northerly most of the time. Northerlies are taking advantage of the sunshine to warm each day a few degrees above average.

It won't be until at least late next week before the jetstream shifts far enough north to allow fronts to penetrate further, so significantly cooler and wetter weather is a fair way off.

- Weatherzone

© Weatherzone 2014


Edited by bd bucketingdown (15/05/2014 07:27)

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#1263634 - 15/05/2014 07:37 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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The SSW has now moved east or ENE and is slowly weakening and has transferred the next upstream ridge near South America to a new SSW area...interesting...likely responsible for the easterly wind strengthening near north S American coasts ocean area maybe(as the SSW works its way downwards as per explanation post last page).


Edited by bd bucketingdown (15/05/2014 07:40)

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#1263648 - 15/05/2014 09:54 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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I'd imagine that we wont see anymore temp anomalies until there are further flux bursts into the stratosphere.

As these things go it's been fairly minor so far - but my understanding is it may help to make the stratosphere more vunerable to future penetration.

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#1263671 - 15/05/2014 13:10 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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It has not been so minor here in SA and in other eastern states Snowbaby, as we have really dried out with the SSW giving high domination and drier and warmer weather and looks like continuing for a week or two yet till things settle down...does not help crops and pasture and gardens, though good living weather!
And quoting from Blair Trewin and the SA thread
"If today's ECMWF run is correct and the warm spell remains unbroken until (at least) the end of next week, it will set records for long runs of warm days in May* in Adelaide, Melbourne and Sydney (and probably plenty of other places too, though I haven't checked).

(* - for these purposes I'm including the late May/early June 1957 event, which in some cases, e.g. Adelaide days over 22, surpasses anything contained entirely within May)."


Edited by bd bucketingdown (15/05/2014 13:11)

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#1263757 - 15/05/2014 22:59 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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mmmm...maybe high squatting on se corner will set up pump for some renewed heat flux..

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#1263782 - 16/05/2014 07:43 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Warm autumn day in Hobart sets 100-year record
Thursday May 15, 2014 - 20:29 EST

Hobart has experienced its warmest late autumn day in more than a century.

The state's capital reached 23.9 degrees in the afternoon, making it the warmest day at this time of year since records began in 1896.

Ian Barnes Keoghan of the Bureau of Meteorology says the whole country is experiencing a heatwave.

"We're certainly seeing a lot of very mild weather, that sort of whole south-east part of the country's going through a period of extended very mild weather, which looks like continuing for some little time," he said.

This week is also expected to be the warmest week for this time of year since 1934.

ABC

© ABC 2014

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#1263825 - 16/05/2014 13:57 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
_Johnno_ Offline
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Is the SSWs warming reflected here on the NOAA temperature anomalies shown for the past 7 days for us and well south of Australia? I'm guessing the two are linked?

http://www.esrl.noaa.gov/psd/map/images/rnl/sfctmpmer_07b.rnl.html


Edited by _Johnno_ (16/05/2014 13:57)
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#1263875 - 16/05/2014 20:37 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Yes, I would say so Johnno
cheers

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#1263879 - 16/05/2014 20:47 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Here is a snap of that warm Antarctic temp' anomaly Johnno



The surface anomlaies warm at the Antartic pole with colder anomaly at upper stratosphere 10hpa




I think this means strong descending air compresses air under for high pressure and warming at the surface
The air pushed down is then forced out radially around the Antartic and a belt of low pressure convection emerges

The pattern is very zonal curently
Not what you would see from a SSW atmospheric wave activity. Maybe a bit early.

Last year the SAM went strongly positive first as the wave action started

SAM/AAO curently close to neutral 16th May 2014
http://www.cpc.ncep.noaa.gov/products/precip/CWlink/ENSO/verf/new.aao.shtml

The westerly belt is certainly well contracted south currently with a stalling high in the Tasman

WE still have nice looking North west cloud band arriving


Just have to sit back and see how it all 'pans out'
Thanks for the obs' and keeping the thread alive


Edited by crikey (16/05/2014 20:48)
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#1263885 - 16/05/2014 21:59 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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Loc: Eastern A/Hills SA
The SSW & warming effects are now weakening and things are likely to slowly return to normal temp wise after a while.


Edited by bd bucketingdown (16/05/2014 22:00)

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#1263919 - 17/05/2014 10:57 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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Record late Autumn warmth for Sydney
Drew Casper-Richardson, Saturday May 17, 2014 - 10:31 EST

Sydney is enjoying late Autumn warmth not experienced since temperature records began all the way back in 1859.

The working week ended in spectacular fashion with the city reaching 25 degrees under clear blue skies. Friday was the seventh day in a row where the mercury exceeded 22 degrees, the longest stretch this late in May since records began over 150 years ago. The previous record was six days which occurred in 1974.

The longest run of days exceeding 22 degrees at any time during May is nine which occurred in 1978 and again in 2007. The current forecast is for Sydney to reach 24 or higher for at least the next seven days which will eclipse the current record.

A lack of strong cold fronts has allowed the summer heat to linger over the interior. A near-stationary high pressure system over the Tasman Sea has allowed northerly component winds to filter this heat into the Sydney Basin. The high has also brought mostly sunny skies giving the sun ample time to warm the city.

The warmth isn't over yet though. Since 1859, Sydney has only had 21 days in May where it has reached 25 degrees, making it a one in every seven year event. Including Saturday, five of the next seven days are forecast to reach 25, highlighting just how unseasonably warm it is.

Sydney's average May maximum is 19.4 degrees. The average for this May so far is nearly three degrees higher at 22.1. The highest May average on record is 22.7 in 1958 and with the current forecast this could be broken this year.

- Weatherzone

© Weatherzone 2014

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#1263946 - 17/05/2014 17:47 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Loc: Albany, W.A
Some prognosis reminiscent of the polar vortex being stretched.







There’s been a concentration(380+ du) of ozone south of us for some time which seems to pretty much match the area of the recent stratospheric temp anomaly. There are some studies suggesting an increase ozone in our patch, could be a result of fires(seasonal) in Indonesia etc.






Edited by snowbaby (17/05/2014 17:52)

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#1264369 - 22/05/2014 19:04 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Yes. the SSW warming bubble has subsided considerably
Of note currently is the very strong sub tropical Jetstream
BUT
A VERY WEAK sub polar jet . Almost non existent currently( marked with a purple line on the diagram posted)
This sub polar jet is crucial for our cold fronts . It is looking VERY benign currently



source
http://www.bom.gov.au/australia/charts/v...it=Refresh+View
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#1264398 - 22/05/2014 23:02 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Currently looks like a little flux activity is starting to get into the stratosphere again(19th&20th long arrows think it's wave 1) - hard to compare it to earlier recent bouts as Esrl's EPflux plotter is either not functioning properly some of the time - or when it does is only giving me reading up to 16May.




Edited by snowbaby (22/05/2014 23:11)

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#1264467 - 23/05/2014 17:12 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Ah yes 'snowbaby' I see a new SSW bubble is emerging east at 180 longitude / date line in the sub polar region of course
as seen from the CDAS animation a few posts back
A single blob of SSW curently around the SH sub polar belt
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#1264473 - 23/05/2014 17:53 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Loc: Albany, W.A
...it's pretty quiet on the western front cold outbreak wise - it's all I can find to do of much interest at the mo...hoping that these little flux forays eventually weaken the vortex enough for an exciting late winter/spring..


Edited by snowbaby (23/05/2014 17:55)

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#1264529 - 24/05/2014 22:11 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Registered: 05/08/2009
Posts: 295
Loc: Albany, W.A
Wow quite a spike in wave activity appearing @ 100hPa., 22nd May. Seems to be wave 2 though hard to tell if wave 1 is involved until tomorrow’s outputs perhaps. Extreme right of graph at bottom - sorry I dont have Crikey’s marker pen.



Almost certainly the biggest burst of the year so far - keen to find out whether it’s significantly anomalous or not.

Must be synopticaly induced. Any ideas?


Edited by snowbaby (24/05/2014 22:13)

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#1264544 - 25/05/2014 08:24 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
Posts: 6033
Loc: Eastern A/Hills SA
It does that every year peaking generally in mid winter-early spring in southern hemisphere SB (the waves they measure I mean)


Edited by bd bucketingdown (25/05/2014 08:25)

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#1264784 - 27/05/2014 10:30 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW
Originally Posted By: crikey
Ah yes 'snowbaby' I see a new SSW bubble is emerging east at 180 longitude / date line in the sub polar region of course
as seen from the CDAS animation a few posts back
A single blob of SSW curently around the SH sub polar belt


That bubble appears to have stalled and is gaining strength, with a weak cooler bubble moving in south of Aus now right in time for our cool down after this record heat.

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#1264938 - 28/05/2014 18:04 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Noticing that 10hpa animation is about 4 days behind

Usually 'snow baby' there is significant strong surface MSLP cells in the sub polar region underneath the warm anomaly or near about.
Last year l don't remember the SSW bubble shifting from 120E ( a standing wave perhaps).
This wave has moved and appears to be oscillating between warm and colds somewhat.
Jenni' from New Zealand thread is reporting a strong cold burst
You can see the wave action evolving and creating a crest of cold air over NZ
That cold crest arrived across NZ today.

http://www.bom.gov.au/australia/charts/v...it=Refresh+View

There are some nice deep lows emerging in the surface sub- polar region currently. Hopefully lets hope this gets the wave atmospheric action going and some decent cut off cold pools and good strong fronts.
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#1265309 - 02/06/2014 18:36 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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That warm SSW anomaly is really cranking at 120 W ( southern sub polar-pacific)
Nice strong blob currently. Different location from last year.
The sub polar Jetstream is looking dismally weak still.
The sub- tropical jet very strong across the sub tropics at 200hPa
SAM/AAO marginally negative
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#1265322 - 02/06/2014 21:24 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
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Loc: Lane Cove, Sydney, NSW
Wow, that anomaly is really something crikey! Some of the biggest I think I've seen actually, and now we have the cool spot developing SW of oz, which has me thinking what that means for us moving forward? Thoughts?


Edited by CoastalStorm22 (02/06/2014 21:25)

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#1265326 - 02/06/2014 22:24 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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I'm not sure I'm on the same page - I can only get the animation up to 22May. The most current thing I can get is a 10+ K positive temp anomaly about 90W@May29th from ESRL website




Edited by snowbaby (02/06/2014 22:31)

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#1265332 - 02/06/2014 23:08 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Seira Offline
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Registered: 27/08/2003
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Loc: Adelaide Hills.
Originally Posted By: snowbaby
I'm not sure I'm on the same page - I can only get the animation up to 22May.

http://www.cpc.ncep.noaa.gov/products/intraseasonal/temp10anim.gif

smile

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#1265351 - 03/06/2014 12:34 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
paulcirrus Offline
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Registered: 08/08/2011
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Loc: Brisbane - Windsor
well thats intersting. To be honest out of all the weather i never follow the stratosphere stuff. But looking at Cosmics animation, does this mean a big change in our weather is on the way. That is a huge cold anomoly building to the west of oz and seeing the warm pool head east and deepen makes me think for some stupid reason, it will spell the end of the constant ridging and allow bigger cold fronts north. Well i sure hope my fantasy comes true.
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#1265359 - 03/06/2014 14:07 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
bd bucketingdown Offline
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Registered: 07/02/2008
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Loc: Eastern A/Hills SA
Unfortunately Paul it does not look the same further downwards!...

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#1265366 - 03/06/2014 17:01 Re: Stratospheric sudden warmings (SSWs) [Re: bd bucketingdown]
Mad Elf #1.5 Offline
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Registered: 05/03/2012
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Wow, that chart shows another nasty warm bit west of WA.
Not excited by this at all, looks to me a warm winter is on with substitute water skis instead of snow. Hope it changes.

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#1265371 - 03/06/2014 17:53 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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CS22 said" which has me thinking what that means for us moving forward? Thoughts?

My thoughts CS22
Currently the sub polar jet at 200hpa( lower stratosphere)
is still incredibly benign and almost non existent
Also very zonal currently ( not wavy)
This is bad as some nice deep wavy Jetstream is needed for some deep cold fronts
and the sub -polar jet is currently contracted way south.

The current picture of the upper stratosphere that snowbaby' has posted shows air rising /expanding near sth America but contracting /shrinking /cold anomaly on the other side of the SH near Australia.

This imbalance /disturbance should crank up some wave action in the atmosphere. making the waves more meridonal ( wavy)

Will be fun to watch the effects of this upper air pattern down in the troposphere.
Great some are interested in watching these dynamics unfold

My thoughts are that if the sub polar Jetstream doesn't crank this winter. could be very mild winter.

Hoping for some favourable synoptics to emerge





Edited by crikey (03/06/2014 17:55)
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#1265374 - 03/06/2014 18:13 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Loc: Tweed Heads
Picture of the current MSLP in the SH.
THe westerly belt has swollen/expanded in size as it should for late Autumn and in to winter
But note the zonal (west > east) flow with little wavy activity
therefore no deep fetch cold fronts clipping the mainland

An active sub -polar Jetstream with a meridonal pattern is required to stir the cold around into the more northern latitudes.


source
http://www.bom.gov.au/australia/charts/indian_ocean.shtml

I will do a pic' the Jetstream later as well to illustrate the problem
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#1265378 - 03/06/2014 18:26 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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200ha Jetstream very quiet. Both the sub -tropical and sub polar are zonal ( not wavy)
The sub-polar is exceptionally weak and contracted south and the sub tropical Jetstream has weakened in strength as well
Actually don't think l have seen the jets so inactive for 1st week of winter since l first started observing 3 yrs ago



http://www.bom.gov.au/australia/charts/v...it=Refresh+View
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#1267132 - 23/06/2014 14:12 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Noting 23rdJune 2014..Wave pattern in the upper stratosphere at 10mb is completely zonal and lacking activity. No current SSW warm spots.

Stratosphere at 200 hpa. Sub tropical jet is strong but sub tropical jet remains weak
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#1267236 - 23/06/2014 23:01 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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.... flux burst currently underway @ 10Mb...wonder if vortex will weaken early this year...like to think this currently extreme tight zonal mode might have to be counter balanced by extreme disintegration...


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#1267715 - 27/06/2014 16:36 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Interesting to see the following tropopause height (anomaly?) appearing in past little while over the pole. Haven't found a great deal about the subject as yet. Not sure if it foreshadows any unusual exchange of properties between troposphere and stratosphere. A rough gestimate on my part puts it about 70Mb(perhaps higher). This strange bump(sometimes it’s more fragmented) of what presumably is much colder air sitting in a pocket in the stratosphere really intriguing - anyone any ideas? Cant say I’ve ever seen it before.





Edited by snowbaby (27/06/2014 16:37)

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#1267743 - 27/06/2014 18:24 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Is that an older picture 'snowbaby'?. time stamp 4th July 2014?
However
( see BD's 50hpa animation above)
The 50hpa animation is showing a new warming blob 23rd June south of S/west WA Australia .
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#1268052 - 29/06/2014 08:47 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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I wasn’t very clear - it’s forecast.

Found the following from “Stratosphere Troposphere Interactions: An Introduction”(K Mohanakumar)
“...the warmer temperatures associated with a blocking high cause isentropic surfaces to bend upwards......by pushing transporting tropospheric air poleward and bending the tropopause upwards, blocking highs can increase the time it takes STE processes(stratospheric-tropospheric exchange) to occur...”

If so, weakening of vortex may be delayed.

Like to see these warm anomalies in the surf zone extend further into the vortex itself. If it’s going to happen should pick it up in daily EP flux charts first.

An early breakdown in the vortex would be exciting - w.a seems to get best cold outbreaks well into August - even later, though I have vague impression there’s a bit out there about the breakdown, in recent years, occurring later than even I’d like....

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#1270967 - 24/07/2014 20:23 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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20th July 2014

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#1270972 - 24/07/2014 22:29 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Been some signs of upper vortex temp starting to rise - likely a result of increased planetary wave activity(wave 1).



Been a fairly consistent burst in recent times the graphic below is typical of that.The dashed line contours appearing throughout are indication of flux convergence - that is wave breaking - in this case inside the vortex (as well as in other areas of the troposphere)




Some deformation in the cold 10hPa temperature field away from a very singular concentric pattern vortex- like its being squeezed or displaced a little at this level to perhaps form a bipolar pattern with an area of warmer temps. Neutral or warm anomalies on the vortex at 10 hPa overall.



I cant find this pattern developing in the levels below 10 hPa (and at any level in the geopotential height fields either) - despite the strong anomalies the mean pattern is still basically a more concentric one on the continent.. There’s some analysis I saw recently that 2002’s split in the vortex started at the base (ie:100hPa) - no sign of that at all.

In perspective - the vortex has been very strong. Whilst the 10hPa temp has lifted quite dramatically it has been bumping along at the bottom of the climatological range and is only now getting back to the mean.

While ever the wave activity continues though, an interesting watch period immediately ahead.

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#1273954 - 21/08/2014 18:05 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Wish I had more time to look into it.For a little while now there’s been periods of field distortion in the vortex (weakenings) alternating with periods of re-intensification.

I thought that early this winter the vortex was very strong. Temps were low @ 10hPa at the bottom of the climatalogical range. There was a warming (about mid to end of July) which was not major according to the established standard for these things. However it’s always possible this warming and subsequent periods of wave1 activity have preconditioned the vortex for something dramatic, perhaps a little more dramatic than the typical annual disintegration .

Wave activity is pretty negligible inside the vortex at the present but there are other factors possibly at play - a process called self tuned resonance is believed to have led to the split of 2002. Cant say I’ve got handle on that one as yet....more study to do!

Interestingly though, a similar elongation in the 100hPa temp field to the one below was a precursor in the 2002 event.



I’ve noticed other distortions over the last month or so. For instance the pv distribution below moves dramtically away from the typical stable symetric distribution.





600K represents about 50 hPa unfortunately cant find any charts for higher in vortex.

In general these field distortions have up to now been followed by periods of stable, symetrical distributions as the vortex re- intensifies, seeming to re-establish itself.

In the progged gph@100mb chart for 28 August below it's possible to see a split developing - whether the height field develops in the way forecast and whether it goes as far as actually splitting will make an interesting watch in next little while...a little caution required since a similar pattern to this has emerged before this winter without that happening.


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#1273960 - 21/08/2014 18:52 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
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Thanks for keeping this thread alive 'snowbaby' . There does appear to be a vertical oscillation over the winter. The max on the 28th July 2014

https://picasaweb.google.com/110600540172511797362/Stratosphere2014#6049933733184782498

and the minimum of the wave about now. 21st aug 2014
That is a period of one month. If that oscillation continued the next warming max would be about 21 st Sept. Pure speculation of course. As the SH warms the oscillations weaken


current animation
http://www.cpc.ncep.noaa.gov/products/intraseasonal/temp10anim.gif
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#1274069 - 22/08/2014 17:57 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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I’m probably reading a little too much into the “distortions” in the various parameter fields within the vortex, because, as you hint, they usually turn out to be part of an oscillation - just the extremes in an onging cycle - whatever driving forces are involved.

I always hope there will be a chance to read signs of an imminent threshold event - either a sudden split in the vortex or a displacement. Given that the only split that I know of in the SH was 2002 , it might be a faint hope.

The maths in most of the papers on the subject make it doubly difficult for an enthusiast like myself to get a handle. I can see the benefit of collecting a database of charts as a sort of observational record - but that will take an extended period of time to be of much use.

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#1275674 - 07/09/2014 18:39 Re: Stratospheric sudden warmings (SSWs) [Re: snowbaby]
snowbaby Offline
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Registered: 05/08/2009
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7 Sept

Chart of where the temp field@10hPa is progged to finish 14th Sept.



Quite remarkable sudden shift away from antartcic continent begins about 12th. Cant recall seeing the central node of the temperature field so offset from the continent.At same time a warming trend looks set to spread from the antarctic littoral directly to the south of us.
Temp fields below 10hPa aren’t quite as offset. Reminded of the stack of plates analogy, with the topmost plate sticking way out.

I’m not sure where this is leading.Perhaps a dramatic warming within the vortex if we're lucky?


Also a momentum in movement of entire gph field@10hPa in same direction after the 12th, though not quite matching that of of the temperature field.



Sorry not up to posting animation on my present set-up but link below has it- just follow menus if of interest.

http://weather.uwyo.edu/models/fcst/index.html?MODEL=gfs003

Again, at lower levels there’s a more muted movement(of gph field) in same direction with a lot more elongation and stretching evident especially at 100hPa (below).



At present there is negligible planetary wave activity in the vortex but some dynamic at play.

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#1275676 - 07/09/2014 18:59 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Registered: 05/08/2009
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apologies for the size of pics...a bit slow with the edit and got timed out..something I'll watch in future..

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#1276587 - 16/09/2014 09:06 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Registered: 05/08/2009
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Here’s obs from esrl which tend to confirm that movement of the core of cold vortex temps away from its position over the antarctic continent is underway - as gfs forecasts suggested(my post above).



At the present there’s the accompanying sudden appearence of strong EP flux activity within the vortex @10Mb. JMA charts below(incidentally wave1 generally regarded as most often associated with vortex splitting) - amplitude of wave1 now underway looks massive also first indications of sudden spike in temps@10Mb.(black line right of chart just beginning)



Looking ahead from here gfs progs some pretty hefty warming occuring. Something around the 270K mark would represent a major warming event.



Perhaps we might expect that anomalous weather patterns will emerge in spring - but the caveat of course is that at this stage nothing is certain, though I am encouraged by the sudden appearence in Gfs progs of the first decent cold pools since late June(for w.a).

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#1276683 - 16/09/2014 20:16 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Petros Offline
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Well posted observations SB. Thanks smile

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#1276691 - 16/09/2014 22:30 Re: Stratospheric sudden warmings (SSWs) [Re: snowbaby]
Cutofflow Offline
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Registered: 14/08/2009
Posts: 94
Loc: North Central. VIC
SB,

I have observed that, generally, elnino years produce a decrease in Antarctic Sea Ice Extent. It is quite possible that your observations of a potential upcoming resonance event is likely given we are in a similar setup to that of 12 years ago.

I have been expecting a sharp decline in sea ice extent over western Antarctica since the beginning of this year (an area that currently has a large positive extent due to recent lanina episodes) ( Link ). The warming predicted by GFS could be the catalyst for a reduction in sea ice extent, declining from all time satellite-recorded highs. This is poor timing for southern Victoria as our winter fronts are slipping the slide by this time of the year..

Fore the sake of posterity here is the 2002 resonance event. (10mb and 70mb) (Temps)

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#1276733 - 17/09/2014 16:55 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
MOUNTAIN h2o Offline
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Registered: 23/03/2012
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Loc: Hobart Lenah Valley Tas 198 as...
Originally Posted By: crikey
Thanks for keeping this thread alive 'snowbaby' . There does appear to be a vertical oscillation over the winter. The max on the 28th July 2014

https://picasaweb.google.com/110600540172511797362/Stratosphere2014#6049933733184782498

and the minimum of the wave about now. 21st aug 2014
That is a period of one month. If that oscillation continued the next warming max would be about 21 st Sept. Pure speculation of course. As the SH warms the oscillations weaken


current animation
http://www.cpc.ncep.noaa.gov/products/intraseasonal/temp10anim.gif


Great work again crikey smile We are going from snow today and tomorrow in Hobart to a significant warming event on the 21'st onwards. Just when you thought it may happen , amazing stuff , keep up the great work .

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#1276759 - 17/09/2014 21:39 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Registered: 05/08/2009
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Loc: Albany, W.A

Yeah that's quite amazing from crikey..thanks for pointing it out again Mh20.

The warming being speculated about though is stratospheric - I dont think there's necessarily a direct link between warm anomaly in the stratosphere and warm anomaly in the troposphere. There's still a lot of work being done on understanding stratospheric-tropospheric linkages - I think it is more usual that the anomaly in one will lead to anomalies of the opposite sign in the other, and there is usually a "lag" factor at play in that as well.

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#1278235 - 30/09/2014 07:42 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Registered: 05/08/2009
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Loc: Albany, W.A
This warming we have just seen in the vortex - a rise of 30C - is a significant event
The overall transformative affect on what happens in the troposphere, may be fairly modest though - for the time being anyway. I’d like to think that there is connection in the persistence of cold pools(though nothing really spectacular) with fronts into October> for w.a at least that would be a a bit out of the ordinary in recent years. Pure speculation of course.

Interesting to note the distribution of PV on the 600K surface(about 20hPa I think) charted below - shows accompanying erosion of pv about the time/location of the warming.

For the moment, the vortex remains intact but it may be primed for dramatic weakening and there seems likely to be another period of warming later this week - based on gfs prognosis.

Going from this(30/9)

to this(5/10)


Edited by snowbaby (30/09/2014 07:45)

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#1284493 - 17/11/2014 10:36 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Registered: 05/08/2009
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My rap on this.

Warmings in the vortex in recent times - with hindsight, still have to be considered minor events, according to what I can find on the subject . The rapid temps increases @10mb seemed pretty impressive but not really matched by anomalies in the stratospheric zonal winds - something which might be expected for a major event - particularly a reversal of winds (brings very cold siberian blast in some of the northern hemisphere major warming events).

Progression in charts illustrate marked dissipation of the pv which has begun - as the vortex begins annual breakdown?





Think pv circulates dissipates into the troposphere somewhat at this stage - (maybe with exchange with tropospheric air coming the other way?)- elevated pv concentrations intruding via systems which for instance wracked Tas some time back.(Hence the often repeated observation of spring often producing best snowfalls Tasmania) Also, I like to think, perhaps connections with these warming minor events and the brief anomalous spell of winter like conditions we had here last week - only speculation. More to learn and understand yet.


Edited by snowbaby (17/11/2014 10:40)

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#1293991 - 29/12/2014 09:52 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Registered: 05/08/2009
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Loc: Albany, W.A
There does look to have been a split in the vortex around the 13th of December. Haven’t been checking pv distribution of late - until recently




It’s a little more dramatic on the 475K surface(lower stratosphere)



Had it occurred a lot earlier, I think things might have been a lot more interesting for us all. JMA’s charts show a warming @ 30hPa -perhaps it was confined to mid to lower stratosphere? -beginning early Nov through to early Dec. (btw @10hPa there's no sign of it for that period.)



Its likely that the sudden warming which peaked@10hPa about mid October according to JMA has taken this long to work downward through the mid to lower layers of the vortex. That's what appears to have happened.I am speculating on how this might have worked.

JMA also produced the following which seems to show significant EP flux(wave 2) activity approximating to the time of the split(bottom chart). Wave2 activity is generally associated with splitting while wave1 - though it may play a role in preconditioning the vortex - is usually associated with displacement. (CPC’s charts might be a little misleading as they dont show much wave2 amplitude at that time.)



however might be a case of?

“... following a long period of stable and relatively low-amplitude oscillation, a small (in principle, infinitesimal) change in forcing amplitude leads to a spontaneous vortex split. The small change necessary to cause the split could equally have arisen from a small change in the underlying stratospheric circulation...”
[Mathewman& Esler Nov 2011, Stratospheric Sudden Warmings as Self-Tuning Resonances. Part I: Vortex Splitting Events ]

I’m a little reluctant to get too excited - coming at a fairly late stage when the vortex(and pv) had been in decline and already weakened -the affects, if they can ever be tracked, may end up being underwhelming in any of the ways that most of us would notice. Unsure here whether the affects of a split occurring should be anticipated, rather than affects of the scale of the warming which seems to have induced it.

Perhaps there is a period of possible anomalous weather still to come. Baldwin and others, comment that the anomalous affects of warmings last longer in the southern hemisphere troposphere - up to 90 days (which put us into mid January or well into March depending on which episode you track - the mid Oct one @10hPa or this recent one ).


Edited by snowbaby (29/12/2014 09:56)

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#1294124 - 29/12/2014 21:26 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
adon Offline
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So does that mean drier or wetter?

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#1294304 - 30/12/2014 21:38 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Seira Offline
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Registered: 27/08/2003
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To be honest I don’t think we have an adequate grasp of what’s going on [with SSWs] to make longer-term predictions. A paper here also purports there is more to it, influences extending into the Mesosphere.

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#1294387 - 31/12/2014 11:14 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Registered: 05/08/2009
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Loc: Albany, W.A
Adon

The -Cosmic- (naz) stole my thunder.

I have to restrict myself to my observations because I dont understand much yet. I rely on the work of the atmospheric scientists or meteorologists or whatever title applies -

then spin it into a rambling version I can understand without(I hope) taking too many
liberties.

This stuff is fairly new to everyone - I think it’s fair to say it wasn’t that long ago that it
was thought the stratosphere had little to no influence on our weather. That’s changing,
but I think it’s still a way to anyone being able to reliably forecast from it. Good luck to
you in any case.

..just harking back on the October warming@10hPa for a minute -

Jma’s rise in temp is extreme - from about -55c early Oct to peak -5c about middle of
month



that’s quite staggering and seems in contradiction with noaa's(-20C max?) . .



as it does(to lesser extent) Jma’s other version of 10hPa temperature chart in my earlier post - but since both chart zonal mean temps,perhaps the right assumption’s a smoothing effect at play.(but should the difference be this extreme?)

So far as -55 to -5 goes, I do have a bit of unease “temperature over the south pole”
doesn’t tell a lot about the observation - hope I'm not
missing something.




Edited by snowbaby (31/12/2014 11:21)

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#1294388 - 31/12/2014 11:23 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbaby Offline
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Loc: Albany, W.A
..apologies for the hatchet job on the editing btw..

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#1294455 - 31/12/2014 15:49 Re: Stratospheric sudden warmings (SSWs) [Re: snowbaby]
Seira Offline
Meteorological Motor Mouth

Registered: 27/08/2003
Posts: 7166
Loc: Adelaide Hills.
Originally Posted By: snowbaby
The -Cosmic- (naz) stole my thunder.

Unintentionally smile .
As you indicated:

Originally Posted By: snowbaby
This stuff is fairly new to everyone

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#1386833 - 11/09/2016 18:18 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Registered: 11/05/2016
Posts: 108
First evidence I've noticed this year of rapid warming in the S polar vortex region - imagine that further large amplitude wave activity needed to bring on ssw


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#1434131 - 15/09/2017 22:03 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Registered: 11/05/2016
Posts: 108
Massive EP flux spike showing extreme right lower chart. Select Southern Hemisphere and then "Temperature & Vertical Components of 100 hPa E-P Flux" from dropdown http://ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/

Temps in polar stratosphere have warmed in recent weeks after periods of wave activity. Sometimes wave activity directed poleward and therefore warming trend linked to easterly phase QBO

Sign of decelerating winds on the vortex perimeter
http://www.cpc.ncep.noaa.gov/products/st...JAS_SH_2017.png

Noticed the polar vortex @ 600k looking elongated since about 12th Sept, especially in last day(about 15th I think). Chart can be found here
http://www.pa.op.dlr.de/arctic/ecmwf.php
Select for Antarctic Polar Vortex, PV@600K

PV and Temp fields - esp the latter shifted right off the polar axis.

Crikey! Where are you?

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#1434136 - 15/09/2017 22:26 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW
What does that all mean Snowbaby?

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#1434145 - 16/09/2017 07:28 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Registered: 11/05/2016
Posts: 108
Wish I had a pat answer CS22. Dramatic, dynamic teleconnections to our part of the world.... possibly.

The southern vortex is currently showing anonymously +ve temps. May mean it is vulnerable to penetration by further wave activity if sufficiently weakened.

Stratospheric warming can be associated with splitting of the polar vortex. 2002 was a major split as you may know. I believe there was another partial split in 2014 possibly close to the time of final warming in that year, though I haven't been organised enough to have this confirmed by anyone with credentials.

Cant say it's near or likely to get to the splitting stage but watching with interest.

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#1434157 - 16/09/2017 09:44 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
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Loc: Lane Cove, Sydney, NSW
I don't have twitter but I often follow Amy H Butler who quite often brings up things to do with Antarctica. I find her feed interesting at times. See below her latest comments.

https://twitter.com/DrAHButler/status/907726755984805888



Edited by CoastalStorm22 (16/09/2017 09:44)

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#1434204 - 16/09/2017 21:15 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Registered: 11/05/2016
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Thanks greatly for that CS22 - I might try and put together a note and see of she can confirm if there's anything to my thoughts on southern vortex activity in 2014.

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#1434304 - 18/09/2017 10:59 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Snowbaby, Dr Butler has made a few more interesting comments overnight. Due to near record heat fluxes the ozone hole appears to be elongating which is unusual. Most of the records for heat flux were set in 2002 during that first documented SSW over the SH.

Interesting times!

https://ozonewatch.gsfc.nasa.gov/monthly/SH.html

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#1434342 - 18/09/2017 21:28 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Registered: 11/05/2016
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Thanks for that as well - I have trouble connecting to her page off my machine at home(antiquated OS)- I'll have a look via my local library.

Yeah it looked to me like something was happening with that giant spike showing on JMA charts

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#1434413 - 19/09/2017 21:36 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Registered: 11/05/2016
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Invaluable reading here
https://doi.org/10.1175/JAS-3318.1
on the 2002 split vortex - good visual representation and fairly easy text.

Interesting to look for similarities with current situation.

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#1435074 - 25/09/2017 12:42 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
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Loc: Lane Cove, Sydney, NSW
This years Ozone Hole is currently looking very elongated and small for the time of year.

Sea Ice around Antarctica also currently on lowest in record territory I believe. Very unusual year were having down there.

At the moment the stratosphere above about 50mb is very warm, however, lower down say from about 100-700mb it's cooler than normal so hence the high SAM were currently experiencing, I'd say once the lowers warm the SAM should drop. IMO.










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#1435116 - 25/09/2017 22:29 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Registered: 11/05/2016
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Thanks for that CS22. I'm having difficulty accessing some sites. Interesting that the hole is currently smaller.

From limited charts it looks to me like temp at 50hPa in the polar vortex is just above the temp for polar stratospheric cloud formation, but is forecast to fall near to or below the threshold in near future.

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#1435634 - 01/10/2017 10:27 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Here is fairly recent sizing of the polar vortex. This chart has been updated since I posted - there is a bit of variation from time to time - best to check on cpc site.


The area capable of supporting psc formation fell dramatically early September, right outside the range of the last 10 years by mid month.Apologies- cant seem to get the pic up - direct link to cpc
http://www.cpc.ncep.noaa.gov/products/stratosphere/polar/gif_files/psc_sh.png

How close is the final warming(and the onset of the summer pattern?).
The large quasi-stationery anti-cyclone in the 90E-180 quadrant(same location as the warming) is usually associated with the stripping out of pv from the vortex at the beginning stage of the final warming process.



Note the date stamp on the chart - would be pretty much on time in the seasonal vortex evolution, though since this forecast chart I’ve noticed the large cell has broken down somewhat and a procession of smaller high pressure cells resumed an easterly migration around the vortex - typical of an earlier stage in the annual life cycle.

The deformation of vector streamlines towards the centre of the pole may be suggestive of strong wave activity resuming.

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#1435638 - 01/10/2017 12:48 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Kino Online   content
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Registered: 10/08/2017
Posts: 1272
Loc: Wollongong, NSW, Aus
Fascinating, thanks, any reasons why the activity is so focused/intense over us and no where else? Is it due lack of monitoring sites or associated with Hadley Cell activity?

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#1435756 - 02/10/2017 11:05 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Couple of things - only ways I’m looking at it generally - not specific answers as such -haven’t really thought about role of Hcell or the teleconnections to the troposphere much.

Highest concentrations of 03 in the SH collar region just outside the PSV(PolarStratosphericVortex) are roughly in the quadrant mentioned. As polar night retreats hydrostatic balance requires anti-cyclonic development following any warming.

Perhaps it can be argued that there was a slight shift westward from the area of highest frequency of blocking in the SH, towards 90E -180 in September.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/blocking/real_time_sh/real_time_index_nrm.shtml

I visualise blocking as an important component in planetary wave driving which may be guided into the interior of the PSV and cause it to weaken as seems to have happened this year.

The PSV rotates on its axis it seems independently from the parameter fields(and the anti-cyclone) in the collar region.

But at other times, the cells in the collar region suddenly begins to circle in concert with the PSV’s rotation - that part at least might describe in some mechanical way, the eastward migration of these cells -they usually decay over mid-pacific at the earlier stage,rather than coalesce into a single intense high cell prior to the initiation of the final warming.

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#1435760 - 02/10/2017 11:58 Re: Stratospheric sudden warmings (SSWs) [Re: snowbooby]
CoastalStorm22 Offline
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Registered: 10/07/2006
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Loc: Lane Cove, Sydney, NSW
Originally Posted By: snowbooby

Couple of things - only ways I’m looking at it generally - not specific answers as such -haven’t really thought about role of Hcell or the teleconnections to the troposphere much.

Highest concentrations of 03 in the SH collar region just outside the PSV(PolarStratosphericVortex) are roughly in the quadrant mentioned. As polar night retreats hydrostatic balance requires anti-cyclonic development following any warming.

Perhaps it can be argued that there was a slight shift westward from the area of highest frequency of blocking in the SH, towards 90E -180 in September.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/blocking/real_time_sh/real_time_index_nrm.shtml

I visualise blocking as an important component in planetary wave driving which may be guided into the interior of the PSV and cause it to weaken as seems to have happened this year.

The PSV rotates on its axis it seems independently from the parameter fields(and the anti-cyclone) in the collar region.

But at other times, the cells in the collar region suddenly begins to circle in concert with the PSV’s rotation - that part at least might describe in some mechanical way, the eastward migration of these cells -they usually decay over mid-pacific at the earlier stage,rather than coalesce into a single intense high cell prior to the initiation of the final warming.


Would you say were headed for a later or earlier breakdown of the vortex this year?

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#1435942 - 03/10/2017 11:12 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Earlier or later I'd be doing little more than guessing at this stage.

The large anti-cyclonic cell (@10hpa)dominating our quadrant is forecast to break down somewhat as mentioned( representing a slight fall off in temps) and to circle to about the 90W position, while another cell establishes at 90E.

I think there is some warming that seems to be working it's way down into the lower polar stratosphere - but dont know that it's part of final warming process. More warming probably required from wave driving.

If the two developing cells "squeeze" and elongate the PSV, the formation, which favours wave 2, is thought to make the PSV more vulnerable to splitting (though a rare event in our backyard).




Edited by snowbooby (03/10/2017 11:21)

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#1436141 - 05/10/2017 13:59 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
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Loc: Lane Cove, Sydney, NSW
Smallest September Ozone hole since the freakish 2002 vortex split!

https://atmosphere.copernicus.eu/news-and-media/news/smaller-ozone-hole-observed-september-2017

If we remove 2002 then smallest since the late 80's I believe. Polar vortex looking weaker than normal as well. A weaker vortex will be more susceptible to any warming which could mean an even earlier end to it than last year, which I believe was earlier than normal.

Sea Ice still well below average as it has been all year.







We also still have the fascinating Weddell Polynya phenomenon going on in Antarctica.

https://twitter.com/kryosat/status/914554108396351488

In all a very interesting year going on for us.

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#1436145 - 05/10/2017 15:02 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Kino Online   content
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Registered: 10/08/2017
Posts: 1272
Loc: Wollongong, NSW, Aus
Well, that's interesting (for those like me who didn't know what it was: it's an open area of sea surrounded like by ice).

Weren't they supposed to be suppressed because of you-know-what. #awkward #breakingthenarrative

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#1436157 - 05/10/2017 17:15 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW
In the 1970's they had one(much larger than this year and last) appear three years in a row 74,75 and 76 and until last year they had not observed one since. It's interesting that we have another one this year(in addition to last years) and it will be interesting to see if like the 70's one appears again next year.

Perhaps a symptom of the record low sea ice?

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#1436533 - 10/10/2017 11:58 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW
GEFS showing what looks to be some planetary wave forcing putting the squeeze on the PV over the next 10 days.

Final warming not far off? Vortex already well below average in size making it more susceptible to such forcing. Interesting times!








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#1436559 - 10/10/2017 16:53 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Registered: 11/05/2016
Posts: 108
Nicely done.

I think it could be close. That warming seems to involve lower levels of the PSV whereas many of the earlier episodes were more confined to middle PSV - and this time it looks smack bang over the centre of the continent - at 30hPa and above at least.

Check out this forecast http://db.cger.nies.go.jp/gem/stras/en/forecast_20171009_S_675.html you can see evidence of the concentrations of PV being stripped out of the vortex at each day.

There are quite a few threshold parameters about the place which are used to signify the event as having occurred - probably you'd want to see a reversal of perimeter westerlies?

Not sure how early a FW would be in next little while climatologically - but early for recent years. It was anticipated with the recovery of ozone which seems to have occurred fairly substantially this season


Edited by snowbooby (10/10/2017 17:00)

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#1438577 - 23/10/2017 12:56 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
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Loc: Lane Cove, Sydney, NSW
Looks to me like the final warming is not far off?

What do the more knowledgeable posters think?

Zonal winds at 60s look set drop well below normal!




Big warm up coming in the strat if GFS is correct!

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#1438607 - 23/10/2017 16:06 Re: Stratospheric sudden warmings (SSWs) [Re: CoastalStorm22]
snowbooby Offline
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Registered: 11/05/2016
Posts: 108
Originally Posted By: CoastalStorm22
Looks to me like the final warming is not far off?

What do the more knowledgeable posters think?

Zonal winds at 60s look set drop well below normal!




Big warm up coming in the strat if GFS is correct!


That forecast looks like you'd imagine it.

One measure I’ve seen about the place for final warming is Zonal wind 10ms-1(pardon meant as superscript) @ 50hPa. There are others which are a lot more obtuse and beyond my capacity to work out.Using climate composites at esrl the winds at 50 hPa are in the range ~ 37 ms at present. Last week of Sept it was ~55ms. It doesn’t fall at a constant rate of course - my guess is it varies with wave activity but if it lags temperature changes or not I dont know. Haven’t had time to play about with any correlations.

The rate from top to bottom I’ve seen bandied about is anywhere 10-40days, something like that- about day 265 to about day 305 on that chart. That's 40 days spot on.

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#1438625 - 23/10/2017 18:05 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Kino Online   content
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Registered: 10/08/2017
Posts: 1272
Loc: Wollongong, NSW, Aus
Given the forecast SAM and still quite mobile cold pools where is the warming at?

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#1439601 - 29/10/2017 15:50 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
Seira Offline
Meteorological Motor Mouth

Registered: 27/08/2003
Posts: 7166
Loc: Adelaide Hills.
I think if the longer-wave upper-trough system has strong-enough Jetstream boundaries between them and the sub-tropical ridge, a SSW is more likely to be isolated and not affect the weather layer so much. However, if convergence streams (near the tropopause) are weaker, higher temperature and wind anomalies may leak into the westerly belt. The polar jet I'm referring to.


Edited by Seira (29/10/2017 15:52)

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#1439922 - 30/10/2017 21:55 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Registered: 11/05/2016
Posts: 108
Strange spike on ozone hole charts at
http://www.cpc.ncep.noaa.gov/products/stratosphere/polar/gif_files/ozone_hole_plot.png
around 19-21 October - difficult not to believe it's an error from instruments or transposition of data? otherwise ozone hole disappeared for what..a day?...then came roaring back to finish at about level for 2016.Seems a bit odd.

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#1440076 - 01/11/2017 18:52 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW
Looks as if were about to see the final warming and breakdown of the PV in next few weeks. I think this would be earlier than normal in the ozone hole era.





Zonal winds look set to take a nose dive over the next week also.




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#1440224 - 03/11/2017 23:41 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
CoastalStorm22 Offline
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Registered: 10/07/2006
Posts: 2704
Loc: Lane Cove, Sydney, NSW

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#1441184 - 14/11/2017 22:53 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
snowbooby Offline
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Registered: 11/05/2016
Posts: 108
Zonal winds @ all monitored levels in stratosphere @ 60S as of 14/11 are still stronger than at same moment last year.

https://acd-ext.gsfc.nasa.gov/Data_services/met/ann_data.html

By current forecasts, Zonal Wind at 50hPa,(remembering one suggested proxy for final warming being winds declining to 1ms at that level), look to last a bit longer - by last week of Nov though easterlies will be present@10hPa(again the same forecast from nasa).

If the final warming date of last year is known it might be possible to say if the above situation is a little odd - given the +ve anomylous heat flux the stratospheric vortex has been subject to this season, and the much larger ozone hole of 2016.

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