Recent Solar Cycle Speculation on Phase of NAO/AO

[blizzard1024]

Has any of you seen the latest Sunspot numbers? They have shot up dramatically the last couple months.

http://www.swpc.noaa.gov/SolarCycle/

I read somewhere years ago that higher solar activity favors +NAO/AO...lower activity favors -NAO/AO

all else being equal...(which as we know there are more variables here). This plus La Nina...

could mean a continued mild winter in the east. I don't really try to forecast long range....anyone have

more recent information on solar activity and phase of the AO/NAO?

[nrgjeff]

Correct about solar activity and the oscillations. Most people agree on the general idea, but there is debate on timing. How long does the atmosphere lag the solar state? Funny how those that want a cold winter will tell you the lag is a year or more. A shorter lag, say a few months, leaves the door open for this higher solar activity to influence toward +NAO/AO. Reality is, regardless of cause, they have been hanging out quite positive so far this winter.

Throw in La Nina and signals line up for a mild winter in parts of the South and East. A few forecasters are looking for a flip to -AO/NAO because it was negative part of the summer. I'm favoring a more lasting trend reversal. Continue positive. Now for our friends in the Plains and Midwest, I think it could be an interesting winter due to the storm track out of the southern Rockies. Back East, let your heart not be troubled. It only takes one!

[wxmx]

You can't really remove all other variables and leave SC(max/min) as the sole drivers. There's extensive research showing how the QBO modulates the SC for stratosphere temps, and even how much things are different with same SC phases. It's mostly accepted that -QBO/SCmin and +QBO/SCmax are the preferred states for the onset of SSWs (Sudden stratospheric warmings), with the former having an earlier onset against average, and the latter a later one. But things are not black and white...we are in an incipient -QBO state and about a year from SCmax.

Currently planetary waves from MT (mountain torque) events had been of weak amplitude and not poleward directed, and La Niña doesn't help relative to tropical forcing induced waves. Also, we had a +QBO summer, which probably enhanced/accelerated the Brewer-Dobson circulation which is slow in nature, not allowing for ozone buildup...and that plus near SCmax conditions and enhanced solar wind activity which probably created free radical catalysts that destroyed the already poor tropical production of ozone, promoted lower than average ozone advection to the poles, hence the very cold stratospheric temps in there, and stronger PV.

Things changed wrt the QBO, and we are now in a descending -QBO state, though still weak. That is probably slowing down the B-D circulation, promoting ozone buildup and richer advection to the poles, and if we get a few weeks of below normal sun activity, stratosphere will probably warm wrt average. My window of opportunity for some significant strat warming is the 2nd half of Jan and early Feb.

There has been a weak spot wrt the PV circulation where, in spite of the strong polar night jet, there has been some Rossby wave brief intrusions, allowing for some amplification in the pattern. That point is the W coast of North America, where ridging has continued to build and refused to retrograde, against what it always shows in the 15 days ensemble models, keeping the CONUS colder than average for it's first third, and probably thru the 20th. That's why I think that if we get high latitude blocking it will be in the EPO region, and not the NAO side.

[am19psu]

You can't really remove all other variables and leave SC(max/min) as the sole drivers. There's extensive research showing how the QBO modulates the SC for stratosphere temps, and even how much things are different with same SC phases. It's mostly accepted that -QBO/SCmin and +QBO/SCmax are the preferred states for the onset of SSWs (Sudden stratospheric warmings), with the former having an earlier onset against average, and the latter a later one. But things are not black and white...we are in an incipient -QBO state and about a year from SCmax.

Currently planetary waves from MT (mountain torque) events had been of weak amplitude and not poleward directed, and La Niña doesn't help relative to tropical forcing induced waves. Also, we had a +QBO summer, which probably enhanced/accelerated the Brewer-Dobson circulation which is slow in nature, not allowing for ozone buildup...and that plus near SCmax conditions and enhanced solar wind activity which probably created free radical catalysts that destroyed the already poor tropical production of ozone, promoted lower than average ozone advection to the poles, hence the very cold stratospheric temps in there, and stronger PV.

Things changed wrt the QBO, and we are now in a descending -QBO state, though still weak. That is probably slowing down the B-D circulation, promoting ozone buildup and richer advection to the poles, and if we get a few weeks of below normal sun activity, stratosphere will probably warm wrt average. My window of opportunity for some significant strat warming is the 2nd half of Jan and early Feb.

There has been a weak spot wrt the PV circulation where, in spite of the strong polar night jet, there has been some Rossby wave brief intrusions, allowing for some amplification in the pattern. That point is the W coast of North America, where ridging has continued to build and refused to retrograde, against what it always shows in the 15 days ensemble models, keeping the CONUS colder than average for it's first third, and probably thru the 20th. That's why I think that if we get high latitude blocking it will be in the EPO region, and not the NAO side.

Post of the month, imo

[wxmx]

Post of the month, imo

Thanks, but probably HM will read the post, shake his head and straight things out in a followup post .

[okie333]

You can't really remove all other variables and leave SC(max/min) as the sole drivers. There's extensive research showing how the QBO modulates the SC for stratosphere temps, and even how much things are different with same SC phases. It's mostly accepted that -QBO/SCmin and +QBO/SCmax are the preferred states for the onset of SSWs (Sudden stratospheric warmings), with the former having an earlier onset against average, and the latter a later one. But things are not black and white...we are in an incipient -QBO state and about a year from SCmax.

Currently planetary waves from MT (mountain torque) events had been of weak amplitude and not poleward directed, and La Niña doesn't help relative to tropical forcing induced waves. Also, we had a +QBO summer, which probably enhanced/accelerated the Brewer-Dobson circulation which is slow in nature, not allowing for ozone buildup...and that plus near SCmax conditions and enhanced solar wind activity which probably created free radical catalysts that destroyed the already poor tropical production of ozone, promoted lower than average ozone advection to the poles, hence the very cold stratospheric temps in there, and stronger PV.

Things changed wrt the QBO, and we are now in a descending -QBO state, though still weak. That is probably slowing down the B-D circulation, promoting ozone buildup and richer advection to the poles, and if we get a few weeks of below normal sun activity, stratosphere will probably warm wrt average. My window of opportunity for some significant strat warming is the 2nd half of Jan and early Feb.

There has been a weak spot wrt the PV circulation where, in spite of the strong polar night jet, there has been some Rossby wave brief intrusions, allowing for some amplification in the pattern. That point is the W coast of North America, where ridging has continued to build and refused to retrograde, against what it always shows in the 15 days ensemble models, keeping the CONUS colder than average for it's first third, and probably thru the 20th. That's why I think that if we get high latitude blocking it will be in the EPO region, and not the NAO side.

Ever heard of McFarland?

[wxmx]

Ever heard of McFarland?

That's why I brought McFarland up yesterday. Signals are better for a McFarland signature this year...but without cross-polar flow(the main ingredient) it can't just happen.

[weatherwiz]

Question regarding stratospheric temps around the North Pole region and Arctic region. I believe I have read before that a colder stratosphere tends to lead to more anit-blocking...stronger PV and thus much better chance for a +AO/+NAO. What influences the temperature of the stratosphere besides QBO activity?

Or is it the AO state has the correlation to stratospheric temps rather than the other way around?

[wxmx]

Question regarding stratospheric temps around the North Pole region and Arctic region. I believe I have read before that a colder stratosphere tends to lead to more anit-blocking...stronger PV and thus much better chance for a +AO/+NAO. What influences the temperature of the stratosphere besides QBO activity?

Or is it the AO state has the correlation to stratospheric temps rather than the other way around?

Polar stratospheric ozone accumulations are the main driver of the high latitude stratospheric temps. This ozone is produced where sunlight is abundant...ie. the tropics, and is transported to the poles via de Brewer-Dobson circulation. The QBO and solar influences modulate the quantity of ozone that reaches the poles. The more abundant ozone polar stratospheric reservoir, the warmer and more perturbed stratospheric PV.

Vertical propagating planetary waves, triggered by MT, tropical convection or even early season snow cover can penetrate the polar night jet easier in a perturbed PV. This waves can help displace or split the PV, even reversing the stratospheric winds, from westerly to easterly. If this happens at around 10mb, poleward from 60N then it's said that a sudden stratospheric warming has occurred (SSW), which usually foretell strong/lengthy high latitude blocking periods. Minor warmings can occur, where the winds aren't quite reversed, just very weakened. This can help with the high latitude blocking, though the correlation is not as strong as with SSWs.

[cooling climate]

You can't really remove all other variables and leave SC(max/min) as the sole drivers. There's extensive research showing how the QBO modulates the SC for stratosphere temps, and even how much things are different with same SC phases. It's mostly accepted that -QBO/SCmin and +QBO/SCmax are the preferred states for the onset of SSWs (Sudden stratospheric warmings), with the former having an earlier onset against average, and the latter a later one. But things are not black and white...we are in an incipient -QBO state and about a year from SCmax.

Currently planetary waves from MT (mountain torque) events had been of weak amplitude and not poleward directed, and La Niña doesn't help relative to tropical forcing induced waves. Also, we had a +QBO summer, which probably enhanced/accelerated the Brewer-Dobson circulation which is slow in nature, not allowing for ozone buildup...and that plus near SCmax conditions and enhanced solar wind activity which probably created free radical catalysts that destroyed the already poor tropical production of ozone, promoted lower than average ozone advection to the poles, hence the very cold stratospheric temps in there, and stronger PV.

Things changed wrt the QBO, and we are now in a descending -QBO state, though still weak. That is probably slowing down the B-D circulation, promoting ozone buildup and richer advection to the poles, and if we get a few weeks of below normal sun activity, stratosphere will probably warm wrt average. My window of opportunity for some significant strat warming is the 2nd half of Jan and early Feb.

There has been a weak spot wrt the PV circulation where, in spite of the strong polar night jet, there has been some Rossby wave brief intrusions, allowing for some amplification in the pattern. That point is the W coast of North America, where ridging has continued to build and refused to retrograde, against what it always shows in the 15 days ensemble models, keeping the CONUS colder than average for it's first third, and probably thru the 20th. That's why I think that if we get high latitude blocking it will be in the EPO region, and not the NAO side.

The BDC is a late Autumn and Winter phenomenon and is not present in the summer.

You would also want a more active BDC to increase the levels of Ozone in the stratosphere.

The very cold Stratosphere could be a knock on effect to the very low Ozone concentrations

during last spring.

[wxmx]

The BDC is a late Autumn and Winter phenomenon and is not present in the summer.

You would also want a more active BDC to increase the levels of Ozone in the stratosphere.

The very cold Stratosphere could be a knock on effect to the very low Ozone concentrations

during last spring.

Taking into account that it typically takes more than 6 months for air at 16 km (near the tropical tropopause) to rise up to about 27km (20-30 meters per day), I'm pretty sure the BDC is present all year round, though is sensibly weakened in summer...at least the ozone production is present, though the transportation might not.

You have it backwards, a faster, more active BDC means that there's less time for ozone production, as it leaves the tropics faster. You want it to be weaker, so that it moves slower, and there's more than enough time for ozone to build-up, since ozone production is pretty slow.

Edit: I think we are both right wrt weaker/faster BDC....you want a weaker circulation for build-up near the tropics, and then a faster one to transport it to the poles....BDC is very slow, so different activity stages of the circulation will go trough for a parcel of air when transported from the tropics to the poles. I was talking about a weaker BDC when QBO was positive many months ago, and right now is in the process of transporting more ozone with the easterly descending QBO wave. I guess my post was confusing as to the timeframes of ozone transportation. And yes, you may be right about low ozone concentrations during last spring.

Edit 2: I saw a glaring error on my original post "that is probably slowing down the B-D circulation, promoting ozone buildup and richer advection to the poles", should be accelerating, not slowing down

[CoastalWx]

This is a great thread, good learning tool.

[usedtobe]

Taking into account that it typically takes more than 6 months for air at 16 km (near the tropical tropopause) to rise up to about 27km (20-30 meters per day), I'm pretty sure the BDC is present all year round, though is sensibly weakened in summer...at least the ozone production is present, though the transportation might not.

You have it backwards, a faster, more active BDC means that there's less time for ozone production, as it leaves the tropics faster. You want it to be weaker, so that it moves slower, and there's more than enough time for ozone to build-up, since ozone production is pretty slow.

Edit: I think we are both right wrt weaker/faster BDC....you want a weaker circulation for build-up near the tropics, and then a faster one to transport it to the poles....BDC is very slow, so different activity stages of the circulation will go trough for a parcel of air when transported from the tropics to the poles. I was talking about a weaker BDC when QBO was positive many months ago, and right now is in the process of transporting more ozone with the easterly descending QBO wave. I guess my post was confusing as to the timeframes of ozone transportation. And yes, you may be right about low ozone concentrations during last spring.

Edit 2: I saw a glaring error on my original post "that is probably slowing down the B-D circulation, promoting ozone buildup and richer advection to the poles", should be accelerating, not slowing down

Another important point about ssw events is not all of them downwell and lead to weakened tropospheric vortex. Some downwell, others don't and the ones that do generally have their EP flux aimed at the poles rather than southward towards the equator. For those interested, below I've attached a short paper on waht to look for.

http://center.stelab.nagoya-u.ac.jp/cawses2005/PDF/yamazaki_koji.pdf

You can look at EP flux using the Berlin site.

http://www.geo.fu-berlin.de/en/met/ag/strat/produkte/winterdiagnostics/index.html

[Carvers Gap]

WUWT had a good article a couple of days ago. The geomagnetic Ap Index has crashed, however. Oddly enough, it should go up w/ the sunspot spike. Also, many of the spots are extremely small leading some to speculate that this is the beginning of a new minimum. The sun is really out of whack at the moment. Seems strange to say that. The sun seems to be in unchartered waters at the moment. Could be why the weather is so wild?

WattsUpWithThat and the Sun

...And then of course you have this article.

Scariest environment imaginable...Thanks. That's all you had to say, scariest environment imaginable. (bit too much hype but thought prevoking)