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Messages - sark

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ECMWF operational quite dramatic this morning.  As the most likely time nears for a stratospheric polar vortex disruption, the lastest 10 day gives a very strong signal for a major wave 2 split.

GEPS and GEFS all have it losing strength and the Euro has been showing signs of warming of the strat PV for the past day.

Hype winter stuff

Posting this which has reached positive for the 2nd time only since July. 

Here we are again, with strength in the Arctic Oscillation, strength in the vortex, and zonality in winds.  The forecast is for a strong polar vortex situation, positive Arctic Oscillation

Can it hold?  That is and has been my only concern.  I don't know what this stuff all means, I just know 2019 sucked.  It looks bad.  I know it has been -AO and -AAM in the extreme.  The reason it sucked?  Not necessarily.

who knows.  it could do anything.

Because of what it looks like to me, have to say I expect to have the polar cell cracking open again Jan 16-19.  I would hope I'm wrong and the AO is able to trend outside of neutral for a long time, instead of a dynamic wipeout situation with regular large disturbances at the tropospheric level.

and if true,  it could be solar minimum and ENSO and all that.  But, you would start to expect huge changes in global weather patterns to kick in eventually eh?

Tons and tons of ideas out there.  After well over a year of researching, I don't know if it's merely the IPCC scenario or if it's out of control runaway.  Neither ideas matter.  What is it?  Somewhere in between probably.

Don't know what to hope for but the positive global AAM can help.

I think the key development in recent GFS guidance deterministic models is a shear induced across the North Pole, which is beginning now.  From where I'm sitting, looks like model runs show both a ripple (dark) and shear (light) lines across the North Pole in the troposphere.  This can be seen in a number of ways but presenting 330K cyclonic PV



Once the two packets of anticyclonic air reach the pole simultaneously at about hour 198 (Dec 22 2019) the vortex core collapses.  Everything blocks up after.

Lundgren Spiral at 10hPa, already visible and banding up over the next 5 days,90.00,274

this is the bad moment when packets fold in simultaneously over the pole.  shear across the pole up until this moment.  once it fills with slack air, the vorticity collapses

look at jet stream after

November 25th - December 25th *2016*

potential temperature 1000mb +/- 25C

I am looking for any record of tiny vortexes within a few hundred km of the pole, at points in this animation ... right around Dec 10 and 22 2016

Not exactly at sea level but would be visible at 500mb

This is from an obsolete GFS op det where we see pairs of tiny lows occurring at a sort of simultaneous merger of high latitude blocking from Siberian high, Beringian block and Scandinavian block.  Onset of polar shear.  IMHO this is a modeled instance of vortex core divergence.

Run is GFS OP DET 00Z 12DEC2019 36-276h

Now here is the archive at 1000mb of temperatures for the past month. 

What you see is a minor -AO perturbance starting in early November and then a long recovery which scored the highest AO strength since Mid-April.  And then it sets up for the super block

+/- 25C temp 1000mb works well at any time of the year.  You can see everything. 

our deterministic model guidance is showing in such fine detail something that doesn't exist in the archives.  a butterfly of 500mb anomalies constructed *about* the North Pole

* the US is to the LEFT (sorry)


A five year rolling average gives out some outline as to the looks of this thing.  We can look at it anyway.  Look at the emergence of smaller scales at 500mb :x

*(Click to run the second image, it's a GIF)*

We've come a long way to get where we are.  The trend is your friend.  The stratospheric winter PV is a strong force.  And the atmosphere is an exquisite balance.


May-Oct '19 is #1 highest geopotential over the Arctic in the archives, 2016 in 2nd place

2016 re-takes the title for May-Nov, as does Jan-Nov.  Tropopause will be higher though.

PV splits it all the time so it can go back together... but the Arctic is too warm NOW.  What happens upstream at the vortex core?  well it unravels

Weather will still "work" like usual, and probably be unblocked as there are no real blocks, just breaks, with vortex interaction spooling the temps North & South at 850mb fast & furious and from all angles.  Jet stream is obviously tilting out exhibiting banding or a Lundgren spiral. 

I've gotten the sense that the big game out here is atmospheric superrotation.  There was a very high AAM in early 2018, so after a year with such geopotential heights we have seen spikes in +AAM.

But who knows what will happen next?

Concerned about wind shear at the North Pole on the scale of the jet stream?

GFS shows the Strat PV is a lag

One exemplary run of GFS showing the moment in question 701fluidmechanics2.gif *(click to run)*

And yer latest ECMWF at 7 days out

12Z 12DEC2019 GFS The emergence of small scales in vortex ring collisions

We all see the latest modeling, we are 7 days out from the assembled megablock, not only in the central Arctic, but constructed about the North Pole itself.

It's happening.

Remember in early November when the GFS blacked out on the North Pole and we had heat domes of 360 meters anomaly over 3/4 of a million square kilometers out at hour 360 in the op dets... for like two days?  Nothing too surpising came of it?  Well, I quit my job and got to work.

Over the past 2 days modeling has derived a vortex split in the higher confidence range, but NOT in the stratosphere.  The strat PV is currently strengthening violently and is centered and shrugging off the climbing Rossby wave.  But down at the level of clouds, boys and girls, we got a split coming

We're 7 or 8 days out from seeing a vortex core split.

Long story short, our polar cell vortex has reached upstream in flow to the point where the merged vortex unwinds, and we instead have two co-rotating polar lows.  Put another way, imagine traveling up a wake vortex from an airplane wing on landing.  Where the wingtip vortex and flap vortex meet & merge together is where we are right now.

We're seeing chevrons in vorticity and rays in the jet stream in modeling.  Look at vorticity directly at the North Pole Dec 18-22 and you will see an hourglass created in many recent runs of GFS.  Looking at the end of the run and you get the impression the hourglass thing continues, and we have a shear zone directly at the North Pole

I still think it will close up in the depth of winter, maybe for 6 weeks or something, but 2019 ain't over yet :x

So, co-rotating vortices are not the most stable pair, as they will try to helix around eachother and also start shedding badly downstream.  We will find out how that works on a hemispheric scale.

Actual potential temperatures at 1000mb over the Arctic are drawing a guide.  In the atmosphere what seems to happen is the Siberian High, Beringian Block, and Siberian Block, all assemble at the North Pole and allow two axes of rotation for the polar vortex.

Strat PV disruption following this is very likely, but it will unzip from the surface up and not the top down.  Coupling between trop/strat PV is being seen in the models but not all of them.  However, every single major weather model is locked on to what's coming in the troposphere.

I didn't plan on going today but I guess it's on.  Lots of graphics here:

Global atmospheric angular momentum anomaly 2018-2019.

Arctic sea ice / Re: polar vortex - where?
« on: November 13, 2019, 09:55:11 AM »
This type of chart is a cross section of the entire polar cell, basically.  Geopotential height = what altitude in feet is a certain pressure reading.  This type of chart has a scale of pressure from top to bottom, and the colors represent height anomalies.  Warm air expands and a big area of warm air is high pressure and takes up more space in the atmosphere, so the geopotential height rises

charts can be found here:

watch some Gav's weather vids and Nutrien Ag Solutions forecasts on YouTube and you'll find someone who explains these bits clearly for you

Basically when you look at the Arctic on something like and you see heat anomalies at the surface, pretty sure fire bet there's a high geopotential height anomaly just about directly overhead

We've had a huge geopotential height anomaly over the Arctic for the past 7 months, more than any other year

it comes down to polar vortex destruction pretty much in both hemispheres


UK Met Office seasonal prediction done by a dynamic numerical model ensemble, pictured below is Sea Level Pressure for Nov/Dec/Jan

You wouldn't know it by looking at the product's other maps except maybe the 500mb anomaly.  Temps are high in the Arctic but not over Antarctica, not even at 850mb.  This does predict a deep hole of -60 meters GPH over Greenland/Iceland... but when, and how?

This would be a very positive NAO forecast, +NAM, and negative Southern Annular Mode.  If the sudden & dynamic final warming of the Southern Hemisphere's winter PV hits the Antarctic like it did the Arctic this year, wow.

CFSv2 is on this pattern also in December

but the temps are warm.

Why the low sea level pressure?  Storms?

Global winds reaching close to baseline here.

I'd have to refer you to this for more, since I can't see how to explain it quite yet

I'm so lost, Sark.  Sorry for my ignorance, but what is the GIF showing?

That gif is a 500 mb anomaly from Tropical Tidbits for a mid-August GFS run with an overlaid gif of mechanical precession.

I put it together because it is always possible to see, sometimes quite obvious to see, a retrograde wave of high pressure against the Rossby waves.  The timing seems to be somewhere around 8 days.

Bear in mind this is in forecast and an analysis of operational hour 0's would be more fruitful.  I'm probably working on stringing those together next, to create a chart gif consisting of only historical data as modeled in these weather models with no forecast data, spanning over a month's time, for example.

I'm tending toward this concept that the heat incursions, atmospheric height anomalies, and flow characteristics over the Arctic are less Rossby waves and more "mechanical".  Thought experiment: If the troposopheric polar vortex starts fragmenting, that's bigger than Rossby wave breaks.  In fact, the cycle of fragmentation and slamming back together in the tropospheric polar vortex would guide Rossby wave patterns, as opposed to Rossby wave peaks breaking in the Arctic causing the same thing.

Because dual-and-simultaneous ridges from both sides of the planet meeting at the North Pole doesn't look like Rossby waves to me.  It looks like the polar cell ripping into fragments, mainly two, causing two ridges to be pulled into the Arctic in the void left behind

These aren't wave breaks, it's just empty space where there used to be a polar cell.

The interaction between the packets of "polar cell" is becoming more like the Fujiwhara effect

GFS runs have all slammed into alignment suddenly.  GFS accuracy at 7 days is trending pessimistic

The polar cell is wobbling, gyrating, as well as splitting up?  As a vortex this thing is "roping out" and forming stringers.  that's my view

there's been a real nice oscillation going on this thing all year long ... but ... if this wave is normal howcome there's no word for it when I ask?

folks, I'm sorry about these gifs :>

Expect to see all manner of negative Arctic Oscillation on the GFS today.

"you all know what happens next right"

I do not

What happens next?

it splashes back together again in the middle

The 00Z is coming in and will be one of the more moderate members of the AO ensemble, which I will be checking in morning

I'm been getting sick of looking at 2 polar cells and proving that our May-October period was the worst footing our polar vortex system has ever endured

you all know what happens next right

GFS is running away after hour 240 consistently for several days now.  It's providing lots of very interesting opportunity in things like potential vorticity and jet stream dynamics *all* available on tropical tidbits press > press +++++

but the ECMWF is handling it well

in GFS you can see exactly what happens Nov 14-17.  select 2 PVU pressure & wind on the GFS in NHEM view.  Or just jet stream.  You see big temperate air packets getting pulled in over the Beringian and Scandinavian blocking pattern

from both sides simultaneously :[

There still has been no purple on ECMWF near the 14th-17th.  it's just as bad as GFS frankly but it doesn't achieve the shots colliding in center violently thing

I would expect it to continue to act just as awfully in 2020 if not worse, but we're learning all new ways that it *can* look also

this blob is showing us how bad that frozen in anticyclone jet was over Greenland on October 26.

ridges in the jet stream bending up so high on the planet that they reach the North Pole.  but the polar front keeps this from happening and is the reason for freezing temperatures, that and all the ice conspire to create a polar front

but the polar front is breaking at least every 16 days going on 7 and a half months now.  It's due on the 15th if not the 14th, and that's when it should be peaking

in the GFS these temperate air packets shoot in violently and collide in the middle, which goes bright purple on the 500mb anomaly,  less like a splashing rossby wave and more like a dynamic dual/tri/wobble poling of the whole polar cell ... the whole "thing" ripping in half.

that's why it doesn't make much sense for the wave breaks to strike exactly there simultaneously with the MJO in wave 7 or wherever it is.  it's more like the Fujiwhara effect between two hurricanes.  its not quite a Rossby wave break, it's just stringers in the tropospheric polar vortex.

winds at 10hPa are currently forecast by GEFS on a trajectory to hit 0 somewhere near the end of November.  November 27th is the date to beat for sudden stratospheric warming, that would be the earliest recorded

I don't know which is better, if it just dies early and forms back up, maybe it could be stable.  Or it might just ping pong around the Arctic for a month like it did in 2018, elongate, and then die.  so far this has given the impression of a very dynamic and major sudden stratospheric warming.

this is the 384 forecast hour at Nov 20

I'm trying to show that when you take the seasonal map of a similar period, it will show the similar amounts of delta, I could run them again with same year may-oct but the point remains, I don't see anything tremendous about this years seasonal anomaly when you compare to previous years.

then I must be seeing something wrong

lock the time period, lock the scale, and run ever year in the archive

it's *blinding*

I think your charts are showing a period of a year and a half.

the reason to look at the period of May - October is dual.  One, the event unfolding worldwide.  It started on May Day 2019.  That's what got this thread started. 

I'll repost some images from earlier pages if I think I can answer the question, but it doesn't help when the information is as buried as it is now.  This needs to be collated.

JJA would be a fine period.  2019 beats all there too.  But don't forget May when it all began, and be aware we're into month 7 now

you start broadening the lens from May through October and you have a 100 meter geopotential height anomaly in the Arctic over *that* period?

Those were our stable months.

Looking at month by month temperature anomalies over the past few years bears this out.  It's the Warm Arctic, Cold Continents phenomena.

It has become year round.

Why would 2018 be included in the season May - October of 2019?  (growing season for US Ag)

Since the forecast for this November was so similar to reanalysis Nov '18

I tacked Nov '18 onto the end of the past 6 months

Nothing like it since at least 1948.  November is not needed for that trick.  There is a huge structural anomaly over the North Pole this year.  It is not like the other years.  Not even as bad as summers of 1959 or 1960.  The polar cell is getting shredded apart right now, not like usual.

I bicycled out of the San Juan mountains of Colorado in November of 2016, traveling South.  I remember 2016 on these same charts.  November of 2016 was astonishingly bad, but I remember thinking it's not runaway, got bored and turned away.  It was expected to be bad

May - October, not a time known for Arctic Amplification, with a 6 month polar height anomaly of A HUNDRED METERS

that's unexpected.

we are having a tremendous world-record colossal polar geopotential height centered right over the North Geomagnetic Pole, slashing right through our traditionally stable seasons

nobody can freak out because they'd lose their health insurance.  I get it.  what if next year gets better and it won't do us in until the next solar minimum?  then you'd look like a real jerk

the tropics are flooding freely into the central Arctic like never before, and basically the whole system of polar vorticity just octopuses out in response.  What was that ancient hypothesis of Open Polar Sea, the polar cell is made of islands and the North Pole is Tropical?  maybe a genetic memory of the the late Eocene?

well, that's gonna speed up the day.

whatever is stacked up to cause this is a threat and needs to be confronted IMHO

Lord Jesus, Be a Sunspot

The QBO is proceeding peacefully.

Point in favor of not runaway IMHO

We could create a runaway index.  One factor could be consecutive months being all time record warm.  Length * height of geopotential anomalies over the poles.  Number of sudden stratospheric warmings in the past 10 years.. I think we're at 8 or 9 on that front

Was there two SSW in JFM of 2014?

What else might be included?

This is super far out but it illustrates what Sark is describing perfectly. And while it is super far out I think we will see a look like this by the middle of the month.

That normative anomaly was good.  Less energetic, more diffuse, not as simple.

That's what it looks like now for the 15th.  way more diffuse but right on time for 16 days.  October 26-28th was when the wave break & anticyclone over Greenland reached its apex.  This ain't a frozen in tropospheric polar vortex anticyclone though.  in the subsequent forecasts,  it's just wide open like Oct 4.

seeing that the model is capable of something so structurally severe was blinding.  that was some flavor of runaway.

anyway, this was a great tool at the time

I don't always read this forum.  You're either going to be helpful  or not.

In case anyone missed it.

This got my pulse up.  It was 2 hours before the ECMWF showed a more diffuse setup to the event beginning at hour 240

A lot of forecasters took this run seriously, which surprised me, so what you might have read in the past day about long range weather forecast could have been based on this runaway model.

Ever seen anything like it?

In case anyone missed it, there was a GFS run that flat out ran away after hour 240...

it'll be available here for several more days until it cycles out

As a diagnostic it is a valuable run to look at all the various attributes.  it's one to study.  we're seeing what happens when the polar front is broken completely and tropical air floods in to the Arctic from all sides.  When this happens, the polar cell is completely flung afield.

Subsequent runs have not broke so completely and we're starting to get an inkling of what it will look like.  It's bad.  It adds a 7th month to extreme polar atmospheric height anomalies.  It's a '57 or '59 or '60 on a much warmer Earth.  It's not a runaway in week 3 in the latest runs, but it is bad.

Speaking of:  here's Elwynn Taylor speaking in June of 2018... another who made the mistake of being bullish corn.  Well, ya can't help it :)

What this man saw back in the 80's is extraordinarily interesting and is observed in a chart, although I think the progression has been interrupted somewhat in our new, modern climatology.

The forum / Re: Forum Decorum
« on: November 04, 2019, 06:32:42 AM »
Keep doing your thang.

well here's the deal.  I'm not going to put forward any effort.  I won't necessarily lock, delete, keep going, or stop.

anyone can come and deface it with denier style reasoning and that's fine.  I'm basically finished with the work and the thread is probably not going to be useful, going forward.  this is not the appropriate place, frankly.

that being said, there's really no reason to stop posting updates either.  I just don't know if that will happen or not.

let's hope the idea is batshit and this can come out as a climate thriller novel in a year.  that would be fun.

for now I'll just point you to my twitter @systemrename which gets updated more frequently, because it's been more convenient.

There is an ongoing scientific investigation into whether or not the hemispheres can be connected in this way.

For me, it's much more simple than that.

Isaiah 28:20

The bed is too short to stretch out on, the blanket too narrow to wrap around you.

The forum / Re: Forum Decorum
« on: November 03, 2019, 11:50:44 PM »
locked or unlocked makes no difference to me.  it's unlocked.

The forum / Re: Forum Decorum
« on: November 03, 2019, 09:23:59 PM »
I'm locking my thread, and I've already taken a copy for my use

This line of thinking should be assessed by someone else.  It's not going to be debated emotionally here on this hobby forum.  I'm not here to play scientist with you lot or participate in a nerd fight.

How many times can I repeat the thesis in question?  It must be a round peg for square holes.

Polar vortex destruction is leading to decreasing atmospheric angular momentum, which is a feedback upon itself.

Major factors include:

1) ocean heat / thin sea ice
2) solar minimum
3) annual geopotential heights

If this is true, it is an unassessed feedback in dynamics that could meet the definition of abrupt runaway, a self-reinforcing feedback loop that leads to a relatively rapid change of system mode.

If not true, we'll see AAM roar positive, continuing to oscillate along a reasonable trend line, even if long term in decline.  In that case, it's just abrupt normal apocalyptic mainstream climate change,  which is well covered already.

I've not seen it addressed yet, that's what I'm here for.  I appreciate defending this line of thinking against solid reasoning, but this isn't going to become another forum nerd fight.  This is just a place to put it all down for future reference.

It might be evident in precipitation quantities that exceed the increase expected by mean global temperature.  It might be evident in winds or relative AAM.  I don't even have access to the GSDM as the CPC product was taken down and passwords on GSDMsolutions changed *both* within the past year.

What do I do at this point?

Of course we have positive geopotential height anomalies over the arctic. That happens almost by definition! Arctic Amplification creates warmer air above the Arctic hence the anomalies.
And yes, as we move forward, the anomalies will be bigger and bigger.
Yet, it does not mean that the world is ending (yet)


an intentionally misrepresented proposition that is set up because it is easier to defeat than an opponent's real argument.

and it's a real habit

500 millibar height anomaly +/- 90 meters, period of May 1 - October 31 from 1948 - 2019

these are the years that stuck out in JJA anomalies and a couple of them beat '19 in severity & focus on the North Pole

but now we're kind of pushing 7 months straight :/

I'll have to re-do this on all the years in the archive using May-Oct to know if it beats all.  meanwhile the 06Z GFS is coming in

Lower level winter "splits" are not interesting, they happen every year very routinely. Does not mean anything. Just one example (the first date I randomly picked had it). You can find tons like these every year

this is why we do things like look at anomalies

but this isn't going to be assessed here on this forum.  i'm not here to play scientist, and I'm sure as hell not the one to assess this information

you'd have to beat this, not point at random

It usually doesn't happen all Spring & Summer & Autumn with a period of under 16 days, and then spread to the Southern Hemisphere.

Best I can suggest is check the rainfall quantities.  This should have increased more than the temperature increase would suggest, due to the falling AAM.

if this was 1968 or 1977 there would be less of a problem because the geopotential height over the Arctic was deep.  thick sea ice.  Now we seem to have the issue outlined above.  whatever influences are piled on here are resulting in a system that is showing signs of breaking.

How many stratospheric splits and SSW has the NHEM experienced since 2013?  Seems it ain't 0.6 per year.

When angular momentum is not conserved by parameterization in a weather model, it leads to a too-cold Southern Pole, as the models cannot resolve waves interfering with the stratospheric PV in the Southern hemisphere, and the lost momentum is rained out as precipitation.  Just sayin'

total rainfall should be showing increased in 2019 more than can be expected by the measly +1.3C global temp. I understand it can be difficult to get a good measurement of that.

Our global winds are crashing.

wind speeds at the surface rising, that means atmosphere slowing, right?

There is a convulsion coming

Posing a question, as I have no rigorous understanding as yet of the dynamics here.

Would it perhaps be implied here that there is increasing turbulence resulting in disconnections in behavior between layers of atmosphere? 

Or, if the apparent disconnections is purely coincidental, is what we are seeing evidence of increased turbulence and increased disruption of existing patterns?

That's an interesting question, afraid I can't touch it.

As far as what's in the forecast, the tropospheric polar vortex (or simply "Arctic air") is going to divide rather neatly into two chunks in the week Nov 7-14.  When looking at 50hPa the atmosphere responds in these GFS forecasts.  So basically you get  a perturbation and split polar vortex in the *troposphere* which then propogates upward and reaches as high as the top of the tropopause.

Does this convulsion enter the stratosphere and impact the winter Strat PV?

Not yet.

This is the 10hpa forecast as long as they make it (GFS). NO SPLIT AT ALL.

I hope your other data and musings are more exact

that's a different attribute at a different level.  no bite on the attitude.

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