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sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #250 on: November 04, 2019, 09:40:05 AM »
I don't always read this forum.  You're either going to be helpful  or not.

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #251 on: November 04, 2019, 09:44:03 AM »
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

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #252 on: November 04, 2019, 10:05:55 AM »
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?

jdallen

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #253 on: November 04, 2019, 05:21:44 PM »
When angular momentum is not conserved by parameterization in a weather model,...

HMMM. Another thought popped up... there's a whole kinetic energy dynamic that's in play here as well.  Slowing millions of km3 of atmosphere requires dumping of energy via friction loss as heat, and it's not inconsequential.  The delta vee between equator and pole is over 400 m/sec.  It may be lost over a distance of 10,000km but is far from inconsequential.

Similarly air moving south has an equivalent problem in reverse, but it's picking up kinetic energy off of the ocean or land surface, or translating it out of atmosphere it runs into moving at a different velocity.  It's an interesting illusion, as from the ground we perceive blasts of cold air roaring south, when in fact its us moving at a differential velocity slamming into that cold air which has much lower angular velocity.

But again, more energetic atmosphere means more displacement.  I wonder how that exchange of energy from velocity to heat is being managed in the models (or not, as the case may be) and what kind of heating potential it represents? 

It would be zero-sum over all, as energy dumped in the Arctic would be picked up by air masses being displaced south, but does represent another mechanism by which heat exchange is taking place.  In short, more breakouts over time reflect a decrease in gradient of net enthalpy, I'd imagine.
This space for Rent.

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #254 on: November 05, 2019, 11:18:42 AM »
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

macid

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #255 on: November 05, 2019, 12:02:09 PM »
..
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
..
Can we really deduce something tremendous from a partial period anomaly map? For reference I've plotted the anomaly of the year so far and a similar subset of the past 5 years.

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #256 on: November 05, 2019, 12:48:05 PM »
Why would 2018 be included in the season May - October of 2019?  (growing season for US Ag)

macid

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #257 on: November 05, 2019, 01:09:22 PM »
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.

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #258 on: November 05, 2019, 01:16:08 PM »
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.

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #259 on: November 05, 2019, 01:18:48 PM »
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*

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #260 on: November 05, 2019, 01:26:45 PM »
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

El Cid

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #261 on: November 05, 2019, 01:40:57 PM »
Although I would not put a penny on any 384 hour forecast, I must say that the SSW is actually there! Although the split is not (yet?)
10hpa GFS 384 hrs. let's see how the forecast evolves in the next few days!

macid

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #262 on: November 05, 2019, 02:04:55 PM »
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 see what you mean. Due diligence attached, locked scales to 100,-100, only necessary for the last 2 years..

blumenkraft

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #263 on: November 05, 2019, 05:00:37 PM »
Changes in high-altitude winds over the South Pacific produce long-term effects on the Antarctic

Quote
“The study provides the first evidence of long-term changes in the high-altitude winds of the southern westerly wind belt over the South Pacific,” explains Dr Frank Lamy. “Our findings indicate closer atmospheric ties between the tropics and mid to high latitudes than in other sectors of the Southern Hemisphere, with consequences for global overturning circulation and the storage of atmospheric CO2 in the ocean.”

The team’s findings are also important with regard to understanding current and especially future large-scale climate mechanisms in the comparatively under-researched Southern Hemisphere. One crucial aspect is the coupling of the tropical Pacific with the source of the global climate phenomenon El Niño Southern Oscillation (ENSO) and the West Antarctic. The data shows that the West Antarctic Ice Sheet’s high sensitivity to ENSO in the Pacific sector, which can be seen in satellite observations made over the past few decades, is most likely also significant over much longer time scales. “A change in the high-altitude winds over the South Pacific in response to the increased frequency and intensity of El Niño events that many climate models predict would reduce the stability of the West Antarctic Ice Sheet, while also negatively impacting CO2 storage in the South Pacific,” says Lamy, putting the findings in perspective.

Link >> https://www.awi.de/en/about-us/service/press/press-release/changes-in-high-altitude-winds-over-the-south-pacific-produce-long-term-effects-on-the-antarctic.html

blumenkraft

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #264 on: November 06, 2019, 07:33:25 PM »
More numerous Californian wildfires, the Arctic perspective

Link >> https://eh2r.blogspot.com/2019/11/more-numerous-californian-wildfires.html

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #265 on: November 07, 2019, 04:34:41 AM »
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 +++++

https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=nhem&pkg=mslp_pcpn_frzn&runtime=2019110618&fh=6

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.
« Last Edit: November 07, 2019, 04:40:23 AM by sark »

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #266 on: November 07, 2019, 06:40:05 AM »
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

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.sprd2.gif

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

https://imgur.com/a/rgvIwTv

you all know what happens next right

El Cid

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #267 on: November 07, 2019, 08:04:35 AM »
"you all know what happens next right"

I do not

What happens next?

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #268 on: November 07, 2019, 08:25:52 AM »
"you all know what happens next right"

I do not

What happens next?

it splashes back together again in the middle

El Cid

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sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #270 on: November 07, 2019, 03:13:21 PM »
Expect to see all manner of negative Arctic Oscillation on the GFS today.

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #271 on: November 09, 2019, 03:38:34 AM »
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 :>

blumenkraft

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #272 on: November 09, 2019, 07:52:10 AM »
I'm so lost, Sark.  Sorry for my ignorance, but what is the GIF showing?

macid

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #273 on: November 09, 2019, 01:00:47 PM »
One rotation represents ~5 days, one phase of the MJO? When you follow individuals lows you see them elastically bound to the circle and the square acts as a shield, with edges popping lows down south.

blumenkraft

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #274 on: November 09, 2019, 01:16:00 PM »
Oh, i see it now! Thanks so much, Macid! :)

El Cid

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #275 on: November 09, 2019, 03:48:58 PM »
One rotation represents ~5 days, one phase of the MJO? When you follow individuals lows you see them elastically bound to the circle and the square acts as a shield, with edges popping lows down south.

even if you are right, what does it all mean? what is its significance, relevance to "atomspheric connection, structure and long range weather forecasting"?

Shared Humanity

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #276 on: November 09, 2019, 04:50:41 PM »
I'm so lost, Sark.  Sorry for my ignorance, but what is the GIF showing?

Looks cool though.

blumenkraft

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #277 on: November 09, 2019, 05:03:06 PM »
Yeah, mesmerizing! :)

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #278 on: November 09, 2019, 05:19:43 PM »
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

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #279 on: November 09, 2019, 06:00:27 PM »
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

uniquorn

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #280 on: November 09, 2019, 06:36:39 PM »
<> 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.<>
Great idea.

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #281 on: November 09, 2019, 08:28:47 PM »
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

https://doi.org/10.1175/MWR3293.1

bbr2314

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #282 on: November 09, 2019, 09:41:34 PM »
I have a notion that may be insane but I think it belongs in here with sark's ideas.

Is it possible that, with the collapse of the tropospheric polar cell, that the stratosphere could actually reach the surface in places?

Per Wikipedia, the stratosphere drops as low as 20K feet around the poles and northern latitudes.

IF the tropospheric PV collapses / fragments, why couldn't it be possible that the stratosphere descends to 10K feet (or lower) on occasion in parts of the NHEM? This would result in "holes" in the troposphere where the stratosphere is connected directly to the surface. Perhaps this is part of what SSWs are -- or where they are heading, rather.

This would be quite possible in regions like the northernmost Rockies (the triangle of coldness and further north), as well as the high mountain ranges of Eurasia.

I don't know if I am explaining this well, but I think it would explain why we saw such a sudden drop in Greenland's temperature at the onset of Younger Dryas etc as well. If the polar cell collapses and we have remnant tropospheric PVs, why couldn't it be possible that chunks of the highest elevations then become connected to the stratosphere from time to time during winter -- or even more frequently in other parts of the year?

I have illustrated this below in a series of very poorly produced diagrams. The dark blue lines on the geographic map indicate the areas that could be most prone to stratospheric-surface coupling in instance of complete collapse of the trop polar cell, and the light blue areas would also be prone to impacts due to positioning in between the highly elevated "anchors" for surface-strat-coupling.

Please tell me whether this is insane or if it makes sense -- I suppose I am positing a system where the tropopause is no longer as dominant at the surface at current in future, and where it gives way to stratospheric "intrusions" or holes (massive vortexes) that connect directly with the surface.

This is quite possible IMO because as heights increase and equalize across the North Pole as the sea ice fails completely, there is going to be impetus for massively low heights across the snowbound portions of the highest elevations of the continents (the -500MB anomalies we are now seeing in Siberia and Canada). As the heights keep rising over the Pole, they will keep falling over the highest elevations in these regions. And thus, as tropospheric heights over the Pole equalize with those in mid-latitudes and the tropics to some extent, this results in massive holes ripping open the troposphere atop the highest mountains in the high latitudes, and the stratosphere couples with the surface, producing extreme cold that matches what we see in Greenland's ice records.

blumenkraft

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #283 on: November 10, 2019, 10:40:53 AM »
<> 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.<>
Great idea.

+1

Thanks for the explanation, Sark.

El Cid

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #284 on: November 10, 2019, 11:23:14 AM »
Global winds reaching close to baseline here.


So is the doomsday scenario off?

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #285 on: November 10, 2019, 12:09:31 PM »
Out of curiosity I checked other wind related data at Climate Reanalyzer and found this 10m windspeed anomaly graph. I am not a climate scientist, so I dont understand the relation of Angular Momentum in wind to this. It does seem to show an increase in surface windspeeds over the last decades right?

Edit: Assuming Mr in Sark's graph does stand for mean angular momentum.
« Last Edit: November 10, 2019, 12:16:22 PM by dbarce »

Tor Bejnar

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #286 on: November 10, 2019, 10:12:18 PM »
...
Is it possible that, with the collapse of the tropospheric polar cell, that the stratosphere could actually reach the surface in places?

Per Wikipedia, the stratosphere drops as low as 20K feet around the poles and northern latitudes.
...
Mt. Everest (aka Sagarmatha or Chomolungma in more local languages - I saw it in person in 1980, standing on a bump on the side of a nearby mountain [at ~5,600 m] overlooking 'base camp') is 8.8 km tall, so the troposphere would have to thin more than half there.  Denali (in Alaska) is almost 6.2 km tall, so the troposphere would have to thin more than 2/3rds there.

But what might happen with climate chaos, I haven't a clue.
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

kassy

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #287 on: November 10, 2019, 11:16:35 PM »
Quote
Going upward from the surface, it is the point where air ceases to cool with height, and becomes almost completely dry. More formally, the tropopause is the region of the atmosphere where the environmental lapse rate changes from positive, as it behaves in the troposphere, to the stratospheric negative one. Following is the exact definition used by the World Meteorological Organization:

The boundary between the troposphere and the stratosphere, where an abrupt change in lapse rate usually occurs. It is defined as the lowest level at which the lapse rate decreases to 2 °C/km or less, provided that the average lapse rate between this level and all higher levels within 2 km does not exceed 2 °C/km.[1]

Above is the definition of the tropopause.
Below it lapse rate is 6,5 C/ km

Now these high regions could be very cold but they still get weather from elsewhere so my hunch is that it is not possible.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

bbr2314

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #288 on: November 11, 2019, 02:56:39 AM »
...
Is it possible that, with the collapse of the tropospheric polar cell, that the stratosphere could actually reach the surface in places?

Per Wikipedia, the stratosphere drops as low as 20K feet around the poles and northern latitudes.
...
Mt. Everest (aka Sagarmatha or Chomolungma in more local languages - I saw it in person in 1980, standing on a bump on the side of a nearby mountain [at ~5,600 m] overlooking 'base camp') is 8.8 km tall, so the troposphere would have to thin more than half there.  Denali (in Alaska) is almost 6.2 km tall, so the troposphere would have to thin more than 2/3rds there.

But what might happen with climate chaos, I haven't a clue.

Not to nitpick but this is incorrect -- at Denali the tropopause is at 8KM (on occasion), so at 6.2KM, it only needs to drop ~20% to reach the peak.

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #289 on: November 13, 2019, 09:22:56 AM »
https://www.metoffice.gov.uk/research/climate/seasonal-to-decadal/gpc-outlooks/ens-mean

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

https://www.tropicaltidbits.com/analysis/models/?model=cfs-mon&region=nhem&pkg=mslpa&runtime=2019111206&fh=0

but the temps are warm.

Why the low sea level pressure?  Storms?

El Cid

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #290 on: November 18, 2019, 07:47:07 AM »
Possibly a very serious stratospheric warming event is coming soon. GFS shows  strong warming starting T+10. As stratospheric forecasts are said to be more reliable than troposheric ones, it is more likely to come true than usual T+10 and beyond crap. Such warming are usually followed by a polar vortex split. T+16 10hpa temps shown.

bbr2314

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #291 on: November 19, 2019, 01:35:21 AM »
I think these soundings support the notion that SSWs involve the partial or full collapse of the tropopause. The temperature at the surface, -51F, is only 10-15F warmer than the temperature at 100MB. The stratosphere in this instance appears to extend all the way to the surface. There is no tropopause. !

Will this verify? I don't know. But the models are now honing in on a very MAJOR SSW in the 10-15 day period. And its start is now before D10, in fact, the process of massive upwards heat transport is already underway in the ATL Ocean (IMO) which is preceding the main event up above.


ReverendMilkbone

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #292 on: November 23, 2019, 06:17:41 AM »
Severe-weather.eu has a good write up of the coming warm up over siberia

https://www.severe-weather.eu/global-weather/stratosphere-watch-update-siberia-warming-powerful-fa/

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #293 on: November 30, 2019, 11:18:35 AM »
Global atmospheric angular momentum anomaly 2018-2019.

ReverendMilkbone

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #294 on: December 09, 2019, 06:35:03 AM »
So what is the end result of this tropospheric warming event? 

Also, anyone heard from BBR2314?  He hasn't posted since Nov 20th...

El Cid

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #295 on: December 09, 2019, 08:55:09 AM »
It seems that there is going to be no polar vortex split despite the warming. No split seen on any forecast just some displacement

kassy

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #296 on: December 09, 2019, 01:10:03 PM »
Thanks for the update!

PS: Reverend BBR does not have posting rights anymore.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

SimonF92

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #297 on: December 09, 2019, 01:31:10 PM »
Thanks for the update!

PS: Reverend BBR does not have posting rights anymore.

bbr lost their posting rights? I always enjoyed their comments, they certainly got things percolating  :D.
Bunch of small python Arctic Apps:
https://github.com/SimonF92/Arctic

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #298 on: December 13, 2019, 01:45:19 AM »
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. 

https://www.tropicaltidbits.com/analysis/models/?model=ecmwf&region=nhem&pkg=z500a&runtime=2019121212&fh=192

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:
 https://twitter.com/systemrename

sark

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Re: Atmospheric connections, structure, and long range weather forecasting
« Reply #299 on: December 13, 2019, 01:56:32 AM »
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