AAM and GWO Discussion

[Yes_Probably_Maybe_No]

If the MJO is a tropical signal that induces subtropical affects and subsequent ridging/troughing, does that mean it influences and forces the GWO/AAM budget? Have there been times where the MJO was in phase 2-3-4 and the GWO is 6-7-8?

[Amped]

GLAAM continuing to rise as of January 1st.

[SkiOrDie]

The big rise in the GLAAM over the past several days, if it continues, will be the key to getting the pattern changed and moving both the GWO and MJO into favorable phases for the East. When much of the meteorological community was calling for pattern change through December based on 10-15 day model runs, one could see that the cold solutions were not fitting the pattern imbued by the MJO.

Hard to say if everything is interconnected, is the + dGLAAM/dt because of the breaking up of the AO because of warming in the Stratosphere??? A chicken or egg conundrum.

[HM]

The is the 1st time this season that I've started to get interested in the pattern if the models are right in the re-amplfication of the pattern on day 10. I don't see any snow chances south of 40 before then but think sometime around the 14-16 jan period could be interesting if we get a big storm that tries to put some higher heights over greenland for a few days. The forecast pattern certainly looks a little better than it has and the polar vortex does appear to be weakening.

There is no doubt about it that the major anomalies in place driving the +AO are reversing mid-month. The first warming in the stratosphere allowed for the Siberian warm anomaly to move into the North Pole (already happening). This feature displaces a PV to 45N/160E which goes on to change the N PAC.

The QBO, state of the AAM, solar state and tropical forcing are all switching now.

[HM]

If the MJO is a tropical signal that induces subtropical affects and subsequent ridging/troughing, does that mean it influences and forces the GWO/AAM budget? Have there been times where the MJO was in phase 2-3-4 and the GWO is 6-7-8?

The MJO is a huge contributor the global AAM budget but it isn't the only factor. There have been many times when the GWO and MJO are in opposite phases.

How mountains and friction contribute to the AAM state along with the state of the AO/AAO are also very important. There are also the fringe effects of the QBO and sun which directly influence the AAM, even down to a day-by-day basis.

[HM]

The big rise in the GLAAM over the past several days, if it continues, will be the key to getting the pattern changed and moving both the GWO and MJO into favorable phases for the East. When much of the meteorological community was calling for pattern change through December based on 10-15 day model runs, one could see that the cold solutions were not fitting the pattern imbued by the MJO.

Hard to say if everything is interconnected, is the + dGLAAM/dt because of the breaking up of the AO because of warming in the Stratosphere??? A chicken or egg conundrum.

Great point. The forcing became apparent that December was in trouble. We have finally gotten out of that state and I don't think we are heading back there for any major length of time until possibly February.

And I know this is your first post but I am already a fan of yours for bringing up how a stratospheric feedback mechanism can work the other way too! The warm anomalies dislodge the cold ones too and sometimes violently which creates interesting things for the Tropics!

[SkiOrDie]

Great point. The forcing became apparent that December was in trouble. We have finally gotten out of that state and I don't think we are heading back there for any major length of time until possibly February.

And I know this is your first post but I am already a fan of yours for bringing up how a stratospheric feedback mechanism can work the other way too! The warm anomalies dislodge the cold ones too and sometimes violently which creates interesting things for the Tropics!

Thanks HM. Usually I'm just a lurker on here. I've learned a lot about this stuff on here from folks like you. I think MT events, or that quick rise on the GLAAM charts have correlated better with East cold/pattern changes than the NAO/AO, since the latter can be a victim of bad GFS forecasts.

[HM]

A rapid shift eastward in the Walker / Hadley Cells occurred from Late December into early January that deserves a post. This was in response to the AAM positive tendency and ultimate +AAM spike which extended the Pacific Jet eastward.

Time sensitive loop of the 200mb height anomalies (watch the twin upper lows at 10-20° move from Hawaii to 130W!):

Here's a 5-day mean chart which shows the progression eastward nicely due to the extended Pacific Jet:

This eastward displaced circulation isn't normal with a typical La Niña (more normal when the loop starts). This is why the PNA ridge has been popping frequently in the means.

As you can see, the Alaskan Vortex got pretty intense during the holidays.The stratosphere also started to affect the troposphere during the holidays too, ultimately aiding in the building heights across the North Pole (coupled relationship) during early January.

Watch the last 7 days in action as a small but intense PV anomaly drops out of the North Pole into Northeastern Russia:

http://www.meteo.psu.edu/~gadomski/HEMI500/5dayloop.html (time sensitive).

This is the feature that will alter the North Pacific in the next few days and dislodge the Alaskan Vortex. The ridge begins pumping up Tuesday and intensifies Wednesday through Friday.

[usedtobe]

A rapid shift eastward in the Walker / Hadley Cells occurred from Late December into early January that deserves a post. This was in response to the AAM positive tendency and ultimate +AAM spike which extended the Pacific Jet eastward.

Time sensitive loop of the 200mb height anomalies (watch the twin upper lows at 10-20° move from Hawaii to 130W!):

Here's a 5-day mean chart which shows the progression eastward nicely due to the extended Pacific Jet:

This eastward displaced circulation isn't normal with a typical La Niña (more normal when the loop starts). This is why the PNA ridge has been popping frequently in the means.

As you can see, the Alaskan Vortex got pretty intense during the holidays.The stratosphere also started to affect the troposphere during the holidays too, ultimately aiding in the building heights across the North Pole (coupled relationship) during early January.

Watch the last 7 days in action as a small but intense PV anomaly drops out of the North Pole into Northeastern Russia:

http://www.meteo.psu...0/5dayloop.html (time sensitive).

This is the feature that will alter the North Pacific in the next few days and dislodge the Alaskan Vortex. The ridge begins pumping up Tuesday and intensifies Wednesday through Friday.

Nice post it fits the GWO being in phase 7 or 8. I meant to complement to last night but got to watching the games and never got back.

[QVectorman]

Excellent post above

HM, I have been looking at the charts and wondering if we can make any forecast for the MJO traveling through phase 8/1/2 based off the GWO even though the ECMWF models are forecasting COD to phase 3. My conjecture based on the chart on the previous page is that since relative AAM is positive that it should help pull the MJO into phase 7/8 (although amplitude would be a question) and relative dAAM/dt appears to be negative so it would help pull the MJO through to phase 1/2. Also backing that assumption from the GWO chart that since we have negative frictional torque it will favor phase 8 of the GWO which correlates to S. American/African convection which coincides with phase 8/1 of the MJO. Is this thinking flawed?

[Yes_Probably_Maybe_No]

Seeing poleward -AAM transport over the past 20 days, a signal for some high latitude blocking (or at least lessening of +AO/NAO state) near term? Relative AAM tendency also moving similarly.

Positive frictional torque from 35-50N suggests removal of negative torque and weakening of ridges and we could see the pac jet attack the NW US. Is the positive frictional torque a result of the southward +AAM transport from mid-late December?

The AAM budget is a difficult concept to grasp but pretty cool to watch unfold even if it's only the basic stuff that I can follow along with. I don't know how you guys can use the AAM past forecasting a week out. I remember reading Ed Berry's Atmospheric Insights page where he took stabs at weeks 2-3 and I was like

[WxMidwest]

Atmospheric Insights, one of my favorite all-time blogs...

[HM]

I wanted to discuss the global regime shift currently in / been in progress and what events have lead to this current pattern. I am merely offering suggestions and possible explanations but I am certainly not insinuating anything with this information. What this means potentially for the second half of winter is anyone's guess, at this point.

Onto the info....

There was a classic southward momentum transport on 1/13 (this is when the GWO was orbiting from phase 5 to 7) with westerly 150mb winds into the equatorial regions and easterlies across the Mid Latitudes. Polar highs were favored with a downward AO at the time.

Here is the u-wind at 250mb for 1/13 showing the positive /westerly winds in the Equatorial Regions and somewhat negative / easterly winds in the Mid Latitudes:

For 1/24, the wind anomalies have finally returned to a more stable configuration but they are not by any means like the first half of the winter. The anomalous upper low in the western Pacific has been eradicated and the Hadley/Walker Circulation has returned to a more appropriate alignment (still a bit east of normal and not quite axis-symmetric).

Now that the stable +AO/polar vortex has taken a beating with a weakened westerly jet, the eastern hemisphere wave circulation is more poleward than before with a very large area of diffluence over the western Tropical Pacific and eastern Indian Ocean.

It appears that the regime has shifted from the early part of the winter, for sure.

Looking at the relative angular momentum anomalies for the last year (tropospheric on the left / tropopause into lower stratosphere on the right), you can see that both this January and last January saw a robust shift in the state of the AAM.

In January 2011, the negative anomalies propagated to the Subtropics (Latitude -AAM / +AAM anomalies reversed) while this year the negative anomalies propagated poleward. The reflection on the Polar Jet is indicated to the right with the easterly wind being replaced with a strengthening westerly wind last year (not surprisingly a rising AO) while this year is seeing the opposite (yes the AO has fallen considerably). This is about as beautiful as it gets in climate in terms of pattern / symmetry and it is quite awesome how both this year and last year saw a very similar transitional time period.

Zooming in on 2012, the notable switch in the AAM anomalies currently going on is well represented on the latest Frictional Torque graphics (which just show how the global winds have been shifting).

From mid-November through early January, negative FT anomalies gripped the 45-60N belt while positive anomalies remained stagnant over the 20-40N belt. This has recently switched (black circle) and indicates that the strong westerly Mid Latitude Jet is dead.

For more on torques (if this just isn't sinking in / understandable) please read...

"Mountains, the Global Frictional Torque, and the Circulation over the Pacific-North American Region" by Klaus Weickmann:

http://journals.amet...TA%3E2.0.CO%3B2

Anyway, let's compare the 250mb and 150mb geopotential height anomalies from 11/15/11-1/10/12 (left two images) to 1/10/12-1/21/12 (right two images) to get an idea of what all this talk actually looks like on a weather map:

Between the stagnant tropical forcing / stagnant AAM anomalies, anomalous upper level westerly equatorial stratopause winds (no SAO switch this year), descending westerly QBO with a solar spike greater than the projected maximum (essentially the opposite states for an early winter warm stratosphere at the North Pole) and La Niña Walker / Hadley Cell...you can't get an uglier depiction if you are hoping for blocking. The "extended autumn" of 2011-12 with an anomalous poleward jet stream / larger than normal barotropic atmosphere, ITCZ that wouldn't retreat and killer parameters for a blocking atmosphere made the maps you see on the left. Since the global regime shift ~ Jan 10th, things have begun to reverse. The Arctic Oscillation state has definitely flipped with low anomalies becoming dislodged into the Mid Latitudes. The westerly jet has been obliterated and Tropical heights have significantly cooled.

The state of the Arctic has switched as well with a pronounced switch from very cold to warm. This, in turn, has made the tropical stratosphere significantly colder:

The 30-70mb temperatures have significantly cooled across the Tropics. The 30mb cooling is somewhat related to the new -QBO but remember this is a 25S-25N average. This has more to do with the warming polar stratosphere.

On the top are the 60-90N charts and on the bottom are the minimum temps (the polar vortex). A significant warming of the polar atmosphere is in progress, which is cooling the Tropical atmosphere. For a visual representation of this, go to the CPC AO page, scroll down and watch/click on the 50-10mb loops:

http://www.cpc.ncep...._index/ao.shtml

Outside of the Central Tropical Pacific, where enhanced stability from La Niña halts convection, the convection has become more uniform over the Equatorial Regions instead of being focused out of the power-house West Pacific Warm Pool. The uplift zones from the eastern Tropical Pacific / Southern America into the Indian Ocean are all currently more dominate than they were from late December into early January.

As the TSI / sunspot activity slowly declines into late-winter and with the cool anomalies residing over the Tropics from the recent stratospheric warming, the cooler than normal equatorial regions will prevail (along with a weakened ENSO-forcing uplift/walker). The potential will be there for an MJO wave to develop. We have not seen a true MJO wave since the autumn with a very long-lived wave that started in late September. This wave went around the equatorial regions nearly 3 times before finally dampening to ENSO forcing by December. Ever since, the tropical forcing has been stagnant.

Despite what the octant charts indicate, there are actually two areas where wind/OLR anomalies are juxtaposed for a possible MJO wave. Some of the strongest anomalies, currently, are coming from the Indian Ocean. Roundy also agrees...

http://www.atmos.alb...S_7.5N/2012.png

Perhaps the recent global events are currently muddling the waves / forcing. Most likely as we continue forward and move beyond the peak of this period, the true frequencies will emerge. The overly large area of diffluence over the warm pool regions and favorable cool temps in lower stratosphere are allowing many active regions from the IO into the W. Pac.

[usedtobe]

I guess the question is whether we are now in a weak vortex event that will get and keep the ao negative through the winter or will the ao muddle around from negative to neutral for the remainder of the winter. Another question is what impact does the recent solar storm have on things. That's something I don't know much about.

[HM]

I guess the question is whether we are now in a weak vortex event that will get and keep the ao negative through the winter or will the ao muddle around from negative to neutral for the remainder of the winter. Another question is what impact does the recent solar storm have on things. That's something I don't know much about.

Assuming the IO convection and / west pac convection transverse eastward and the phase 4-6 regions see a continual decline, the AO will likely not return to very positive levels. I don't think we return to the early winter AO readings again this winter but this heavily depends on the things I described above continuing to play out. I suspect we see a legitimate MJO wave next month, possibly bringing another period of winter to the East. In the Mid-Atlantic forums yesterday I said it could possibly be Feb 15-25 for a possible phase 8-1-2-3 progression.

As for the current solar event, we'll have to wait and see what the damage is and what kind of effects it will have on the AO. Proton bursts have been shown to affect ozone (destroying it) and cooling the vortex. We are currently getting the late December / early January bombardment of coronal hole activity. Solar wind climaxed ~ 1/12-13 with CH 492-3 and then activity dropped off for a while. This next round of CH waves and possible solar wind peak will be coming in the 2/5-2/12 period when CH 487-88 revisit.

I have no proof of this yet, but the solar wind may be having more of an impact on the pattern now than it did when winter began. Perhaps the lowering TSI / sunspot activity from early winter and changing QBO states are allowing geomagnetic activity to become better correlated to the climate/weather.

[Big O]

Great write-up. Do you believe this will affect the sensible weather in the CONUS in February? March?

In what ways?

[NJwinter23]

Cool write up man. My interpretation would be that this does not imply a complete reversal of the early winter pattern (in terms of sensible weather in the east) through the remainder of the winter, but that we will at least have chances/a 5-10 day period or two for winter as we move through March... instead of the straight nothingness that was November - January ~15th

[HM]

Great write-up. Do you believe this will affect the sensible weather in the CONUS in February? March?

In what ways?

Cool write up man. My interpretation would be that this does not imply a complete reversal of the early winter pattern (in terms of sensible weather in the east) through the remainder of the winter, but that we will at least have chances/a 5-10 day period or two for winter as we move through March... instead of the straight nothingness that was November - January ~15th

I agree with this assessment. The changing state of the forcing will give rise to periods of winter / favorable wave behavior instead of the early winter stagnancy that was occurring. The IO-forcing PNA ridge next week is a good example and will set up a potential threat.

[CoastalWx]

This is why American WX rules. I encourage many who post on topics to accompany their posts with pics to explain why. HM...that post kicks ass. That allows enthusiasts and heck....even mets like myself to see what you mean. Great stuff.

[HM]

This is why American WX rules. I encourage many who post on topics to accompany their posts with pics to explain why. HM...that post kicks ass. That allows enthusiasts and heck....even mets like myself to see what you mean. Great stuff.

Thanks man. I know there are a lot of people on here who want to know the "whys" to the global teleconnection state and pattern. This type of post needs to be supplemented with graphics because a lot of this jargon / technical talk is not as complicated as it first appears to be. Seeing it on every day weather maps playing out is the only way to understand it and reading the papers while taking observations.

Just a word of warning...for all of you who don't remember...last year at this time when the AAM state was changing etc. it lead to a significant model forecast degradation during that period (late Jan-early Feb). I suspect this is likely again, so expect, at the very least, wild shifts in timing in the day 2-5 period.

[JERSEYSNOWROB]

Wow extremely fascinating stuff! Great info as always HM! Glad to have you and all the other mets here on board! Tremendous learning experience for me and I'm sure most of us.

[Ginx snewx]

HM, fantastic read. Interesting comment on model mayhem during AAM change.

[Met1985]

Hey Mets great right up guys. It is like being in a Met class room! Great stuff and wow learning a lot!

[Huffwx]

Very cool, HM-- need to reread it later to process it more, but that's a good thing.

[Lorenzo]

HM - thanks for that write up and review - pitched brilliantly. Hats off to you.

[QVectorman]

Excellent post above

HM, I have been looking at the charts and wondering if we can make any forecast for the MJO traveling through phase 8/1/2 based off the GWO even though the ECMWF models are forecasting COD to phase 3. My conjecture based on the chart on the previous page is that since relative AAM is positive that it should help pull the MJO into phase 7/8 (although amplitude would be a question) and relative dAAM/dt appears to be negative so it would help pull the MJO through to phase 1/2. Also backing that assumption from the GWO chart that since we have negative frictional torque it will favor phase 8 of the GWO which correlates to S. American/African convection which coincides with phase 8/1 of the MJO. Is this thinking flawed?

HM posted this back on the 9th...just wondering if the forecasting of the GWO and MJO from frictional torque and AAM have a lag time say 2 or 3 weeks (or more like 2 or 3 days) or is the response with the MJO forecasted to travel into phase 7/8 by most of the models today a result of the last 7 days or so of events you noted in your post above. (BTW great work! Good read!)

[HM]

HM posted this back on the 9th...just wondering if the forecasting of the GWO and MJO from frictional torque and AAM have a lag time say 2 or 3 weeks or is the response with the MJO forecasted to travel into phase 7/8 by most of the models today a result of the last 7 days or so of events you noted in your post above. (BTW great work! Good read!)

Tricky question and to be honest, I am not quite sure. There is definitely a feedback between what the convection at t=0 did to the wind state and what those global winds at t=1 did to the convection. In terms of lag, papers I've read usually correlate torques / teleconnections more so than a feedback on the MJO and this is because it is understood that the global winds are usually caused by a certain state of forcing (so tropical forcing arrives phase 8-1-2 causing an Aleutian Low / extended Jet which makes the +FT anomalies in the Mid-Latitudes. This +FT correlates to a +MT 3-8 days later as convection moves through the IO). On a global scale, these torques have shown a correlation too and I would imagine they are heightened when the MJO is coherent.

In terms of this upcoming period, several things stood out that caught my attention for why this wave may potentially propagate (some of which was posted already). I don't think you can ever simplify it and say, "hey the GWO has been doing this so the MJO might do this..." 100% of the time.

[QVectorman]

Thanks! I was reading a paper by ed Barry at the time. Trying to put his thoughts and concepts to real world use but I don't think he made mention either of the time scale for impacts from A to B in the paper. I'll have to go back and check.

[HM]

On a semi-related note, it is interesting to look back to the ideas presented in the autumn and see how/why they were possibly conceived. The idea of a colder mid January ended up being briefer in duration, despite the switch in important global parameters (mentioned above). There seems to be a lag in these concepts that must be adjusted for in future forecasts. Also, the idea that February could end up the colder month being spouted off early in the outlook season due to stratospheric changes and possible tropical changes seems to be coming to fruition (although it is only 1/27!). While a MMW has yet to be classified (and may never), it is interesting to note the similar progression on the stratospheric charts to 2005-06 along with the MJO, downwelling-nature to the warming and the record warm January.

I know for me, going back and forth between January or February being the wintriest / coldest month in the Northeast was a tough call and seemed like a toss-up. It is looking like potentially February. Once again, it appears the bias of rushing these larger scale processes is the biggest problem during the autumn-outlook season (before we all changed our tune about the winter, I'm talking like Aug-Oct).

[SkiOrDie]

Question...the ECMWF MJO forecast is strongly moving into phase 7 and possibly phase 8. Aren't these phases only possible with +GLAAM? It doesn't seem like +GLAAM is in the near future. Or is the ECMWF MJO forecast picking up on a MT event before it is reflected in the GLAMM observations?