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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
Weatherzone Addict

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
Meteorological Motor Mouth

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
Weatherzone Addict

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
Weatherzone Addict

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
Weatherzone Addict

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
Weatherzone Addict

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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This post and any other post by Locke is NOT an official forecast & should not be used as such. It's just my opinion & may or may not be backed by sound meteorological data. For official information, refer to Australian Bureau of Meteorology products.

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#1198011 - 07/06/2013 20:04 Re: Stratospheric sudden warmings (SSWs) [Re: crikey]
crikey Offline
Weatherzone Addict

Registered: 01/02/2011
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
Meteorological Motor Mouth

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
Occasional Visitor

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
Meteorological Motor Mouth

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
Weatherzone Addict

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
Meteorological Motor Mouth

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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