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​​​​​​​LEARNING ABOUT TELECONNECTION SCIENCE AND BACKGROUND SIGNALS

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Screenshot_20180113-191858.thumb.png.fd96e6b1767048a17edacf305417048c.png

Looking at the above tweet from Knocker, I was under the impression that the relative strength / intensity of the MJO was signified on the phase chart above, by the points / track being further away from the globe centre? Looks very close in the above instance however the way that tweet plays out, it looks to be signifying a greater than usual intensity? 

Any help with basics on interpreting the MJO phase diagram would be appreciated thanks 👍

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9 minutes ago, ghoneym said:

Screenshot_20180113-191858.thumb.png.fd96e6b1767048a17edacf305417048c.png

Looking at the above tweet from Knocker, I was under the impression that the relative strength / intensity of the MJO was signified on the phase chart above, by the points / track being further away from the globe centre? Looks very close in the above instance however the way that tweet plays out, it looks to be signifying a greater than usual intensity? 

Any help with basics on interpreting the MJO phase diagram would be appreciated thanks 👍

You might find this useful. The phases are under index on second page

http://la.climatologie.free.fr/MJO/MJO-english.htm#1

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After reading that document knocker posted the link to, and from what i can gather, the MJO is active during la nina states and not so much during el nino states. So what i am taking from Mr Ventrice's tweets is that he is merely highlighting the fact that the MJO is active, and seeing as we are in a la nina state this is not unusual. Is he purely showing off the effect of the west to east trade winds from la nina meeting the easterly moving MJO and it's forcing effect on the jet streams causing intensification? I assume this is a  typical event during a la nina state? 

Also what is meant by "doing work" on the NH circulation? 

Sooooo many questions....sorry 🙈

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Going to cross post this thread from the MOD - not sure how the MOD thread reacts to this kind of thing... but for those interested in pacific forcings very glad to have comments, disagreements, embelishments on what is below. We never stop learning - me especially when it comes to weather - so all debate is healthy debate. I posted this:

 

"Time for a post. A lot happening in background forcings at the moment. Remember the elastic band?

So - frictionals look to have turned to an upwards movement (though a bit slower than expected if I'm honest) with graph now heading back up

Frictional Torque

and mountain torque also on the up. Andean South American torque in the wrong hemisphere for us, but note East Asian and Rocky Mts trending upwards once again leading to the global spike

Mountain Torque

MJO moving through the Indian Ocean and still forecast to cross the maritimes into the western pacific with, to my eye, amplitude sufficient to impact on NH circulation

twc_globe_mjo_vp200.png

 

All of this serving to increase angular momentum to a position where it can begin to impact on high lat circulation via poleward wave propagation. Note the steep spike here - though my previous post of "how high" can it go and for how long will it be sustained remains extremely salient

Tendency of Relative AAM

All this pretty much as expected with timescales remaining relevant... so given lag time we are experiencing a key resultant response not this week but next.

However absolutely no getting away from the fact that ensemble data today has shunted the wave pattern a good bit, and ECM ensemble runs for the start of week beginning 22 Jan are not as pretty as they could be or were a day or so ago. Note the deep dig of the trough into Europe as expected, but it is currently forecast to be too far east to assist sufficiently in supporting height rises over Scandy. 

ecmwf-ens_z500a_nhem_9.png

In simple terms the horseshoe of heights to the north remains but with more azores high influence and flat Nina forcing in the atlantic still present.

I'd emphasise the word "currently" because this is an evolving situation. ECM operational chart for 192 this morning to me reflects a whole basked of uncertainty - its a curious chart prior to NWP turning on the atlantic "tap" once again afterwards.... but it says to me that week beginning 22 Jan remains far from resolved.

ECM1-192.GIF?14-12

Without doubt pacific forcings are impacting on NWP at this point... and the question "how high" can AAM ping back and how sustained can ongoing MJO activity be in the face of the same cold Nina waters that blocked it in Xmas week retains key significance. NWP is simply a reflection of these equatorial and ocean/atmospheric battles that are ongoing.

And what if it goes wrong - and Nina wins out again? We would move back into another waiting game of cycles. We would need to wait another fortnight for frictional/mountain torque activity to come back around... and for MJO (hopefully) to reach the ideal 7/8 orbit in early February. Note quite interesting stratospheric developments as signposted by far more knowledgeable people than me with the Jan 23rd chart showing a decent wave 2 signal for vortex attack.. and lag effects of this would also point to early/mid February impact. 

[ECMWF 240 hour forecast from January 13 2018 12 UTC to January 23 2018 12 UTC: geopotential wave 2]

And so this winter keeps giving and giving in terms of interest. So far no snow IMBY but plenty of knife edge interest on a week by week basis. I hope readers of this thread can keep perspective going forward - we have been close to some excellent synoptics this season so far, and close enough for many regions to see some decent if rather transient snowfall. High ground to the north has been pasted consistently and Scotland has had a "proper" winter for sure. This is already better than any of the last 4 winters and we still have plenty of interest on the horizon. Even if southern England ends the season without a winter wonderland experience it will have been a fine run thing... and as we head into the solar minimum, forecast to bottom out in Oct 2019, we can expect winters more conducive to less atlantic impact over the next few years. Scant compensation for those wanting "snow tomorrow" I suppose... but for those who acknowledge the reality of our atlantic climate and infrequent brush with very cold airstreams it is actually something to look forward to!

Anyway - all eyes on the pacific surge and MJO battle. Model output will reflect how these drivers evolve. Cold zonality this week, and then next week still up for grabs I think."

Edited by Catacol

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17 hours ago, knocker said:

You might find this useful. The phases are under index on second page

http://la.climatologie.free.fr/MJO/MJO-english.htm#1

Handy link that Knocker. Relevant at the moment is the strength of trade easterlies in the central and eastern pacific. Heavyweights from across the pond are noting them with raised eyebrow (at least in my mind that's the body language :-) ) and how much progress the MJO can make to 7/8 in the face of such strong Nina opposition remains to be seen. I had a good pm exchange with Tamara early season about Nina forecasts and my expectation that Nina would start to wane by now. In fact that hasnt quite panned out. It has shifted a little further east opening the door through the maritimes, but where it is in force it has actually strengthened a little more than expected. I wonder how close to moderate it will get once this winter is archived post-hindcast. It certainly isnt helping with those forcings trying to amplify the atlantic.

Edited by Catacol

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32 minutes ago, Catacol said:

So - frictionals look to have turned to an upwards movement (though a bit slower than expected if I'm honest) with graph now heading back up

Yeah the FT has been negative for a longer time than expected by most. But it makes sense, with the slowly moving MJO signal in the IO, which causes the -FT. But as you said, AAM should go to the positive side soon enough, it just might be slower than many expect.

IMG_3671.thumb.GIF.ec56aff75dcc1b7a21c20648c92be854.GIF

EC Monthly shows a nice movement of the MJO, however it is slow, and the best phases, which are 6 & 7, don't come until Mid February. 

IMG_3674.thumb.PNG.2ccfd27d67aa00097230abbdb542984d.PNG

POAMA shows a similar timeline. So the MJO progression will be slow, which could allow for maximum tropical +FT to bring a knock on effect on Worldwide MT, and therefore affect the jetstream.

 

 

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44 minutes ago, Snowy Hibbo said:

Yeah the FT has been negative for a longer time than expected by most. But it makes sense, with the slowly moving MJO signal in the IO, which causes the -FT. But as you said, AAM should go to the positive side soon enough, it just might be slower than many expect.

IMG_3671.thumb.GIF.ec56aff75dcc1b7a21c20648c92be854.GIF

EC Monthly shows a nice movement of the MJO, however it is slow, and the best phases, which are 6 & 7, don't come until Mid February. 

IMG_3674.thumb.PNG.2ccfd27d67aa00097230abbdb542984d.PNG

POAMA shows a similar timeline. So the MJO progression will be slow, which could allow for maximum tropical +FT to bring a knock on effect on Worldwide MT, and therefore affect the jetstream.

Oh dear - I'm lost again!:shok:

What, if it's not the Financial Times, is the FT?:fool::help::D

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10 hours ago, Ed Stone said:

Oh dear - I'm lost again!:shok:

What, if it's not the Financial Times, is the FT?:fool::help::D

Frictional Torque.

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And according to a throw away from Fergie vis the METO, the models are struggling a little with goings on in the Pacific

:shok:

 

Edited by knocker

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On 1/14/2018 at 12:36, Catacol said:

(POST SNIPPED)

Going to cross post this thread from the MOD - not sure how the MOD thread reacts to this kind of thing... but for those interested in pacific forcings very glad to have comments, disagreements, embelishments on what is below. We never stop learning - me especially when it comes to weather - so all debate is healthy debate. I posted this:

"Time for a post. A lot happening in background forcings at the moment. Remember the elastic band?

So - frictionals look to have turned to an upwards movement (though a bit slower than expected if I'm honest) with graph now heading back up

and mountain torque also on the up. Andean South American torque in the wrong hemisphere for us, but note East Asian and Rocky Mts trending upwards once again leading to the global spike

MJO moving through the Indian Ocean and still forecast to cross the maritimes into the western pacific with, to my eye, amplitude sufficient to impact on NH circulation

Without doubt pacific forcings are impacting on NWP at this point... and the question "how high" can AAM ping back and how sustained can ongoing MJO activity be in the face of the same cold Nina waters that blocked it in Xmas week retains key significance. NWP is simply a reflection of these equatorial and ocean/atmospheric battles that are ongoing.

 

A great post Catacol. Thank you. I've been digging around to find papers that will help my understanding of 'frictionals' and their impact on weather/climate and wondered whether you have any links to some you could share? Also, links to the best websites for obtaining the latest charts?

I copied extracts of a couple of papers so folk visiting this thread can quickly see if the contents are relevant/of interest to them. In the first paper https://www.sciencedirect.com/science/article/pii/S1674984716300301 I thought Section 1 contained a reasonably easy-to-understand description of the 3 variants:

The atmospheric torques can be dividing generally into mountain torque, friction torque, and gravity wave drag torque.
Mountain torque is a function of pressure and orography, which exerted the solid Earth through a difference in pressure across any raised Earth surface. The most significant mountain torque is locating in the mountains or mountain massifs regions. For example, if the pressure over the west slope of the mountain is stronger than that over the east side, it acts to push the Earth to rotate faster and slows the atmosphere rotation down, which imparting angular momentum from the atmosphere to the solid Earth.
The friction torque is the wind or oceanic current frictional force on the solid Earth surface, which will directly speed or slow down the rotation of solid Earth. If there is a net global eastward surface wind, the atmosphere wind friction force will speed the solid Earth's rotation up, transfer the atmospheric angular momentum to the solid Earth, and thus the atmosphere loses angular momentum.
The gravity wave drag torque is part of the mountain and friction torque that is too small to be resolved by present Global Circulation Models (GCMs), due to the nature of coarse resolution of climate models will not resolve the regional/local mountains and mountain-induced waves, and their contribution to the mountain torque.

I thought this second paper http://www.csr.utexas.edu/eos/reports/95anual/page5.html further helped my understanding by giving some 'real' examples:

Angular momentum has been shown to be essentially in balance among the components of the Earth system, namely the mantle, the oceans, the atmosphere, and the core. .......... Understanding the causes for the changes in the angular momentum of the various components requires a knowledge of the mechanisms that effect its transfer across the component boundaries. ......During one weekly portion of the SEARCH'92 campaign, we were able to isolate the mechanism responsible for a rapid acceleration of the atmosphere: the passage of a high pressure center from the western to the eastern side of the South American Andes in July/August 1992. ...... During the northern hemisphere winter of 1994, another intensive campaign captured a similar event of atmospheric angular momentum transfer by mountain torques, although this time acting across the Rocky Mountains of North America.

QUESTION - When the atmosphere loses angular momentum can this equate to a less powerful jet-stream circulating and higher incidence of blocking?

QUESTION - Different topic, but in your post you covered the MJO currently moving through the Indian Ocean. I see there's a powerful Tropical Storm Berguitta currently moving across the Indian Ocean. Will this enhance the MJO impact (i.e. amplitude) or is it merely a consequence of the MJO?

Thanks in advance.

Edited by Blessed Weather
Added MJO question.

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Hello Malcolm, welcome to our friendly thread. What a great first post on here and thank you for making such an effort. You've obviously given yourself some homework and spent a good deal of time reading up on this part of the subject to prepare this contribution. I'm fairly sure that you'll see several of the specialists dealing with this when they have time to do justice to it (not sure how quickly that will be - like everyone else they have busy lives). From my still limited (and basic) understanding of angular momentum, it's a pretty complex science and will need to be broken down into the sequence of events (what causes what) but once one masters those basics, things really start to make a lot of sense. Anyway, I will not interfere any further until they've had a chance to respond,.I have plenty of questions to ask about many aspects of this fascinating subject myself and I'll come in with those in a few days time. I'll be posting myself later in the week. All the best, David

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14 hours ago, Blessed Weather said:

QUESTION - When the atmosphere loses angular momentum can this equate to a less powerful jet-stream circulating and higher incidence of blocking?

QUESTION - Different topic, but in your post you covered the MJO currently moving through the Indian Ocean. I see there's a powerful Tropical Storm Berguitta currently moving across the Indian Ocean. Will this enhance the MJO impact (i.e. amplitude) or is it merely a consequence of the MJO?

1. Yes it can.

2. It (Berguitta) is a consequence of the MJO, plus various other factors.

Edited by Snowy Hibbo

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14 hours ago, Blessed Weather said:

A great post Catacol. Thank you. I've been digging around to find papers that will help my understanding of 'frictionals' and their impact on weather/climate and wondered whether you have any links to some you could share? Also, links to the best websites for obtaining the latest charts?

I copied extracts of a couple of papers so folk visiting this thread can quickly see if the contents are relevant/of interest to them. In the first paper https://www.sciencedirect.com/science/article/pii/S1674984716300301 I thought Section 1 contained a reasonably easy-to-understand description of the 3 variants:

The atmospheric torques can be dividing generally into mountain torque, friction torque, and gravity wave drag torque.
Mountain torque is a function of pressure and orography, which exerted the solid Earth through a difference in pressure across any raised Earth surface. The most significant mountain torque is locating in the mountains or mountain massifs regions. For example, if the pressure over the west slope of the mountain is stronger than that over the east side, it acts to push the Earth to rotate faster and slows the atmosphere rotation down, which imparting angular momentum from the atmosphere to the solid Earth.
The friction torque is the wind or oceanic current frictional force on the solid Earth surface, which will directly speed or slow down the rotation of solid Earth. If there is a net global eastward surface wind, the atmosphere wind friction force will speed the solid Earth's rotation up, transfer the atmospheric angular momentum to the solid Earth, and thus the atmosphere loses angular momentum.
The gravity wave drag torque is part of the mountain and friction torque that is too small to be resolved by present Global Circulation Models (GCMs), due to the nature of coarse resolution of climate models will not resolve the regional/local mountains and mountain-induced waves, and their contribution to the mountain torque.

I thought this second paper http://www.csr.utexas.edu/eos/reports/95anual/page5.html further helped my understanding by giving some 'real' examples:

Angular momentum has been shown to be essentially in balance among the components of the Earth system, namely the mantle, the oceans, the atmosphere, and the core. .......... Understanding the causes for the changes in the angular momentum of the various components requires a knowledge of the mechanisms that effect its transfer across the component boundaries. ......During one weekly portion of the SEARCH'92 campaign, we were able to isolate the mechanism responsible for a rapid acceleration of the atmosphere: the passage of a high pressure center from the western to the eastern side of the South American Andes in July/August 1992. ...... During the northern hemisphere winter of 1994, another intensive campaign captured a similar event of atmospheric angular momentum transfer by mountain torques, although this time acting across the Rocky Mountains of North America.

QUESTION - When the atmosphere loses angular momentum can this equate to a less powerful jet-stream circulating and higher incidence of blocking?

QUESTION - Different topic, but in your post you covered the MJO currently moving through the Indian Ocean. I see there's a powerful Tropical Storm Berguitta currently moving across the Indian Ocean. Will this enhance the MJO impact (i.e. amplitude) or is it merely a consequence of the MJO?

Thanks in advance.

That first study looks pretty good, and shows a good overview of the two main types of torque, and a lesser torque as well.

This paper may be useful as well, talking about the different torques and their relationships.

1520-0493(2003)131%3C2608:MTGFTA%3E2.0.C

And this chart shows the GWO circulation, and the background consequences/signals, that lead to a certain GWO phase.

IMG_3690.thumb.JPG.f62d0cc7379df896fa486c55f8dc6bad.JPG

 

This would be where the GFS GWO forecasts live, plus GWO correlations.

http://www.atmos.albany.edu/student/nschiral/gwo.html

Beware of the -AAM bias on those forecasts.

 

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21 minutes ago, Snowy Hibbo said:

This paper may be useful as well, talking about the different torques and their relationships.

1520-0493(2003)131%3C2608:MTGFTA%3E2.0.C

(snipped)

 

Many thanks for the response SH. Could you re-do the link please - doesn't seem to work. Thks.

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Yesterday I posted in the Stratosphere Thread an encouraging tweet from Amy Butler about the possibility of a Sudden Stratospheric Warming (SSW) by end-January. My post included Wave 1 and 2 activity forecasts for the next 14 days showing ongoing disturbances to the Stratospheric Polar Vortex (SPV) that are holding back the SPV from growing stronger (with the implication of a stronger Jet Stream and more mobile westerly pattern for the UK). In an ideal situation the Wave activity would lead to a full blown SSW with the SPV zonal winds reversing and cold polar air spilling into the mid latitudes (with weak Jet Stream and high latitude blocking).
(My full post: https://www.netweather.tv/forum/topic/88772-stratosphere-temperature-watch-201718/?do=findComment&comment=3714053)

I would like to gain a much better understanding of what causes Waves 1 and 2 so that I am able to look at, for example, NWP forecast synoptic patterns or specific teleconnection forecasts (AAM, GWO, MJO etc.) and be able to understand the possible implications for the SPV.

From my basic learning of AAM, GWO, MJO and ENSO teleconnections I am already realising that this is an enormously complicated subject with teleconnections interacting with the other (or cancelling each other out) and that different teleconnection phases have different implications. And I'm concluding that it seems incorrect to try and look at what's happening in the stratosphere without understanding what's happening with other teleconnections.

I am picking up from the posts of others that there are currently a few 'issues' holding back the ideal position we would like to be in to have a chance of a SSW and possibility of meaningful cold in the UK. A key issue seems to be an El Nina base state (easterlies in the tropics) that is holding back AAM and which ideally needs to be countered? But at least on this point the MJO is moving eastwards and will help? I note the interesting discussions between @Singularity and @Snowy Hibbo about AAM needing to rise sufficiently in GWO Phase 3/4 to help push a SSW.

So (once again) I would be grateful for (a) recommended reading material to further my understanding, and (b) maybe a high level overview of where we currently are (AAM, GWO, MJO etc) and what we ideally want to happen over the next few weeks. 

Finally, any comments please on this statement from Dr. Judah Cohen in his latest weekly blog, yesterday 15/01/18. Is the pattern change he talks of driving a Wave 2 attack on the SPV?

" Eurasia has been dominated by ridging/positive geopotential height anomalies and mostly relatively mild temperatures.  However, over the next two weeks ridging is predicted to centered in Western Asia/Eastern Europe allowing for troughing on both edges of the continent and colder temperatures in Western Europe and especially Siberia and East Asia. Ural ridging/blocking with downstream troughing in East Asia and/or near the Aleutians is once again favorable for active energy transfer from the troposphere to the stratosphere and should rea-activate stratosphere-troposphere coupling.  The strongest pulse into the stratosphere of the season is predicted for this week. The pulse is predicted to weaken the current strong stratospheric polar vortex (PV), erasing cold stratospheric PCHs and returning a positive stratospheric AO to neutral."

Link to blog: http://www.aer.com/science-research/climate-weather/arctic-oscillation

Thanks in anticipation.


 

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I want to help out BW but I'm not sure if I can without breaking the rules of my work contract. If there's anything I'm allowed to share, I will place it here in due course.

Hopefully there are others who know of the same resources already that can help out here. Best of luck gathering what you need, it would be great to hear your opinions on the potential in winters to come (or other times of year, why not?) :good:.

One thing you'll discover is just how far head we can get a pretty good idea for the potential developments, but with uncertainties on timing that lead to a lot more exchanges along the lines of 

'so much for X!'

'X is still very much on the table, it's just that Y has not got to where it needs to be as quickly/smoothly as it could have done'.

 

So er, among other things... you have that to look forward to :D.

Edited by Singularity

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On 1/16/2018 at 10:50, Blessed Weather said:

(Snipped)

So (once again) I would be grateful for (a) recommended reading material to further my understanding, and (b) maybe a high level overview of where we currently are (AAM, GWO, MJO etc) and what we ideally want to happen over the next few weeks.

May I put on the record my appreciation to @Tamara for sending me a very helpful and supportive pm as I strive to learn more about the fascinating subject of the teleconnections that drive our weather and climate. Tamara had actually already answered my question (reproduced above) in the comprehensive post she had made in the Model thread last Sunday 14th January. You can find Tamara's post here:
https://www.netweather.tv/forum/topic/89152-model-output-discussion-mid-winter/?do=findComment&comment=3713041
Thanks Tamara.

And also a thank you to @Singularity for your encouraging comments above!

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Hi, y'all know me:)

First of all many thanks @Bring Back1962-63 for the hard background work that went into setting up the thread, and especially the research element of his opening posts.

@Blessed Weather You are welcome - most here will try and reply by whichever method is most convenient at the time.   Thanks for copying over the 14th January post , I am also copying over todays model output discussion post which in itself contains large reference to a post made on 2nd January.

For learning emphasis, the description of the different torque processes that define mid and higher latitude patterns under the current La Nina, and which are relevant to most La Nina events, is maybe especially important in that post.

The theme I have adopted this season is related to La Nina being associated with the evolution of blocking, more particularly in the first part of winter prior to the annual seasonal winter polar vortex getting itself organised. That leads to expectation of cold weather, no more so than this year - after all blocking is often construed to imply cold weather in winter. Which it can of course, but its important to differentiate between mid and higher latitude blocking in terms of strength, depth and persistence of cold air advection

In truth, the recurring theme of my posts has in fact applied to all seasons back to and including last winter that has seen neutral ENSO/weak La Nina wax, then wane for a time, but then finally wax again through summer 2017, Its been focussed on the persistent arrangement of circum-global sub tropical ridges created by the tendency of the atmosphere to boost the easterly trades winds in the tropics - as is characteristic of La Nina.

Typically under La Nina, the greatest amplification of the hemispheric pattern is found within the Pacific, with a downstream configuration of a pattern dictated by sub tropical highs pushed poleward to mid latitudes in both the Pacific and Atlantic. So in the Atlantic/European sector, prominent ridging is a common feature from both the SE US/Bermuda and Azores ridges. The common theme being the easterly trades underpinning the Pacific and Atlantic ridges,  and with increased polar westerly jet flow above them

These more enhanced than usual ridges c/o the low level easterlies that underpin them, play a large part in steering hurricanes in the southern Atlantic on the perimeter of these high pressure belts. Its because La Nina features enhanced easterly trades that its one very good reason why hurricanes sustain and are more frequent in the prone areas of the Caribbean and Gulf/Atlantic regions of the U.S - they encounter less head-wind shear that interferes with their structure and development

But back to the task at hand. On the basis as described above, changes in jet flow above these highs revolve around changes and deceleration and acceleration within the generally easterly trade dominated wind-flows from the tropics. The MJO tropical convection is often responsible for these variations and alters the propagation of global wind-flows by at times adding westerly momentum across the tropics as the convection wave heads eastwards and creating amplification of the mid latitude ridges (under La Nina) further downstream.

Downstream patterns like this are actually common in the summer as well as winter under a typical La Nina regime - note the prominent Azores/Atlantic ridge which is kept westwards and away from the classic position further eastwards into Europe that often give the best sunny and warm weather in the UK and nearby Europe.

Instead the retracted and amplified Atlantic ridge tends to feature a downstream cool trough. This pattern repeatedly occurred into the autumn of 2017 and gave a much cooler and wetter September than seen for some years

gfs-2017080800-0-6.pnggfs-2017091400-0-6.png

This type of La Nina like amplified Atlantic blocking with downstream troughs c/o polar jet flow around them continued during the late autumn and early winter

gfs-2017111200-0-6.pnggfs-2017112800-0-6.png

Many more archive charts through the years can be found to support these patterns, but this type of theme is very common to them. .

So a wider intra-seasonal perspective of what a La Nina pattern can imply in terms of synoptic blocking and associated weather types. Generally not conducive for either summer warmth or sustained winter cold - though of course there are a-typical examples of which both last summer and this winter were considered to be potential examples of....

...But that is part of the on-going MOD summary discussion and for another day and another time....

To conclude this post, and which is actually shorter and less comprehensive than originally intended (my computer crashed and I lost the original!) I am posting a technical link that describes the processes of the GSDM (Global Synoptic Dynamical Model).

http://journals.ametsoc.org/doi/full/10.1175/MWR3293.1

I have decided in this second attempt at this post (!) not to attempt to go into detail of its contents, but see if anyone is brave enough to try to read through it. Its bound to create some difficulties, but it is a large part of what I have tried to wade through in the last couple of years to try and get some further insight into this fascinating but not widely known concept model of atmospheric dynamics. It was put together by Klaus Weickmann and Ed Berry, two officers from noaa who have subsequently retired and taken the official links at noaa away with them.

But it still provides a useful insight into the complexities of trying to forecast and anticipate the evolution of medium and longer range NWP. Or simply provide alternate suggestions and solutions like I try to do on the MOD.

But it is also very much why some of us have taken this on, to help within the best of the ability of their own learning curve, on net weather:).

 

Edited by Tamara

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That's a great first post on here @Tamara and thank you so much for your efforts. I'm sure that it'll provoke many questions. I know that you have other commitments and will not always be able to respond quickly but your answers will always be worth waiting for! Just had a glance at the "GSDM" link that you provide and you're right, that's a great source and wealth of information that I'll keep returning to. It's a bit like a text book one is given at the beginning of the new year as a student and needs to be read in conjunction with all the learning on this thread. I promise to do all my homework, miss!

I'm in the middle of preparing my next post for this thread which should be ready tomorrow morning. So, I'll save any questions that I have for you until after that.

I look forward to your future contributions on here and perhaps we shall get a good thread discussion going before too long.

Thank you again, David  

Edited by Guest

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Would I be. correct in saying that MJO phase 4 as depicted in the diagram below is where we are at on the current MJO cycle?

5a60cbe2e9880_ScreenShot2018-01-18at16_25_35.thumb.png.d0417cb8a90586e776407c41ef7987d9.png

And if so when looking at this global wind map the North / west side of Australia would depict what the MJO actually looks like in terms of wind patterns and intensity ( low intensity as depicted on the phase diagram, closer to the centre)? 

5a60ce1e1cebd_ScreenShot2018-01-18at16_39_55.thumb.png.f10fe548a2b5754398ba5ddd55890ed7.png5a60cd26ec452_ScreenShot2018-01-18at16_36_21.thumb.png.034c8c28d4e10c1c346ccabc1ef21070.png

https://earth.nullschool.net/#current/wind/surface/level/orthographic=-63.82,19.80,645.    - link to live animated version of the global wind patterns

Assuming all of the above is correct then when / if we move in to phase 7/8 on the MJO cycle I would assume that the MJO would intensify due to what is currently being shown in the Northern hemisphere around phase 7/8 ? (If said northern hemisphere pattern still looked this way)

5a60cbeda4ba1_ScreenShot2018-01-18at16_29_01.thumb.png.885a478b0ab9f77b2cb0eb45bd760804.png

Circled in black on the GFS NH 500mb heights chart is what I think the model is spewing out as the result of the MJO in phase 7/8 ?

5a60d9daa5279_ScreenShot2018-01-18at17_30_41.thumb.png.62e866c6b26b69f294c087589bcb8a48.png

Then finally if all of the above is correct (again :D) we potentially achieve higher than normal heights in Northern Europe / Scandinavia, why?

Clearly a lot of assumptions here, I am trying to grasp visualy what teleconnections would look like in a more simplistic way, or a way I can understand. Frictional and mountain torques / angular momentums etc I can focus on later I suppose :D

Screen Shot 2018-01-18 at 16.29.59.png

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