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Paul

By Paul
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Griff Veteran

Griff

Posted
  • Location: South Oxfordshire
  • Location: South Oxfordshire
Posted (edited)
5 minutes ago, Steve Murr said:

I saved the old one earlier where you can see the change

D31D7CC1-E7FC-4040-BC07-D5FBD4FAE3DA.thumb.png.dea1c0fa5929f8dd8f4eeabb44571f8a.png

So I totally get the anomaly showing up, but instinctively I'm thinking red is highs and blue is lows... As in pressure, but these are winds? 

Edited by Griff
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SMU Maestro

SMU

Posted
Posted

It

16 minutes ago, Griff said:

So I totally get the anomaly showing up, but instinctively I'm thinking red is highs and blue is lows... As in pressure, but these are winds? 

Is the NAM northern annular mode which represents the polar cap heights throughout the atmosphere from top to bottom.

Positive numbers correspond to a positive NAM which is essentially the same as a Positive AO and vice versa the negative numbers show a negative AO.

The benefit of using a cross sectional map like that is it gives the full spectrum of the atmosphere as opposed to just say the AO ensembles posted. 

When you see positive numbers all the way down it means the troposphere is coupled hand in hand with the stratosphere & its likely to be mild, however if you positive at the top & negative at the bottom around 100HPA you dont have coupling & the troposhere is disconnected allowing for a possible inverse pattern > Negative AO.

You can also see the journey downwards ( propergation) of SSWs through the layers as they happen....

best

S

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Griff Veteran

Griff

Posted
  • Location: South Oxfordshire
  • Location: South Oxfordshire
Posted
6 minutes ago, Steve Murr said:

It

Is the NAM northern annular mode which represents the polar cap heights throughout the atmosphere from top to bottom.

Positive numbers correspond to a positive NAM which is essentially the same as a Positive AO and vice versa the negative numbers show a negative AO.

The benefit of using a cross sectional map like that is it gives the full spectrum of the atmosphere as opposed to just say the AO ensembles posted. 

When you see positive numbers all the way down it means the troposphere is coupled hand in hand with the stratosphere & its likely to be mild, however if you positive at the top & negative at the bottom around 100HPA you dont have coupling & the troposhere is disconnected allowing for a possible inverse pattern > Negative AO.

You can also see the journey downwards ( propergation) of SSWs through the layers as they happen....

best

S

You made that very simple to understand, got it thanks. 

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TSNWK Maestro

TSNWK

Posted
  • Location: Orpington Kent.
  • Location: Orpington Kent.
Posted
2 hours ago, Steve Murr said:

It

Is the NAM northern annular mode which represents the polar cap heights throughout the atmosphere from top to bottom.

Positive numbers correspond to a positive NAM which is essentially the same as a Positive AO and vice versa the negative numbers show a negative AO.

The benefit of using a cross sectional map like that is it gives the full spectrum of the atmosphere as opposed to just say the AO ensembles posted. 

When you see positive numbers all the way down it means the troposphere is coupled hand in hand with the stratosphere & its likely to be mild, however if you positive at the top & negative at the bottom around 100HPA you dont have coupling & the troposhere is disconnected allowing for a possible inverse pattern > Negative AO.

You can also see the journey downwards ( propergation) of SSWs through the layers as they happen....

best

S

Really helpful Steve.. always nice to learn something new, over the years I’ve not understood that chart at all when posted, I do now  and it’s powerful model... 

 

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Paul_1978 Accomplished

Paul_1978

Posted
  • Location: Wakefield, West Yorkshire
  • Location: Wakefield, West Yorkshire
Posted
On 27/11/2020 at 20:30, Griff said:

 

I'm not sure what this means in practical terms for the UK. I deduce that an "arctic low" is not a good thing?

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Don Maestro

Don

Posted
  • Location: Longden, Shropshire
  • Location: Longden, Shropshire
Posted
3 hours ago, Paul_1978 said:

I'm not sure what this means in practical terms for the UK. I deduce that an "arctic low" is not a good thing?

No, but at least it's a long way off.

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Griff Veteran

Griff

Posted
  • Location: South Oxfordshire
  • Location: South Oxfordshire
Posted

Instinctively I'd hazard a guess that this shows a scenario favourable to Atlantic blocking

Happy to be corrected though.... 

 

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Bullseye Community Regular

Bullseye

Posted
  • Location: Southside Glasgow (135m)
  • Weather Preferences: Beginning with S ending with W ;)
  • Location: Southside Glasgow (135m)
Posted

 

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