Arctic Oscillation

[wintersyndrome]

http://www.npr.org/templates/story/story.php?storyId=122649916&ft=1&f=1001

Interesting story

Apparently the cause of the storms the N.E. received after new years was part of this...

Any weather watchers know if this oscillation is still in place? or has it shifted allowing the somewhat warmer temps as of late?

 

[WinnChill]

The AO was off the chart negative at times the past month. It's going slightly positive now with a dip back negative the next week or two.

 

[billski]

I'm thick. So what does this all mean? Are these things (oscillations) here to stay? What's the trend? It's "attributable to weather vaguries." WTF does that mean?

p.s., I spoke to a friend in Sacramento yesterday who is heading to Tahoe-Sierras for the weekend. They got 15 FEET of snow this week.

 

[bigbog]

Being a post-boomer I spent my formative outdoor-activities years in the 60s and early 70s in upper eastern NYS = tons of snow. I guess there are always going to be "rather normal winter" areas whenever..
Granted, more snow off the eastern side of the Atlantic and across Asia...that's interesting...along with the South's extroadinary weather patterns.

 

[WinnChill]

Bill,

It's great you're asking! A lot of it is a bit confusing and it's even tougher to simplify in just a single post here...but I'll try.

The Arctic Oscillation (AO) is just one of many atmospheric or ocean temperature profile oscillations--they're basically large scale upper level troughs and ridges that shift around or vary from positive to negative phases. The AO is positive when large scale troughing hovers around the North Pole and negative when it sags south (it was more negative than usual last month, hence the storminess) Some last a few days, some last months or even years. There is the Pacific North American Oscillation (PNA), the North Atlantic Oscillation (NAO), the Eastern Pacific Oscillation (EPO), the Pacific Decadal Oscillation (PDO), the Quasibienniel Oscillation just to name a few....all of these highlight troughs and ridges in various configurations from the Pacific to the Atlantic and to the poles. It's the various combinations of these oscillations that give us particular weather patterns. Sometimes a positive phase of one along with a negative phase of another delivers potent east coast storms....but perhaps the opposite will slam the west coast with storms...and that's just with only two variables, let alone a combination of all the others. Perhaps one will enhance a particular pattern or even cancel it out. It's fluid and always changing--sort of like my analogy of the Rubiks Cube in another thread. They've been occuring for thousands/millions of years...it's just we're now recognizing these patterns, assigning them cool acronyms, and trying to gauge their frequency so we can identify future patterns.

Hope that helps.

Cheers

 

[billski]

Bill,

It's great you're asking! A lot of it is a bit confusing and it's even tougher to simplify in just a single post here...but I'll try.

The Arctic Oscillation (AO) is just one of many atmospheric or ocean temperature profile oscillations--they're basically large scale upper level troughs and ridges that shift around or vary from positive to negative phases. The AO is positive when large scale troughing hovers around the North Pole and negative when it sags south (it was more negative than usual last month, hence the storminess) Some last a few days, some last months or even years. There is the Pacific North American Oscillation (PNA), the North Atlantic Oscillation (NAO), the Eastern Pacific Oscillation (EPO), the Pacific Decadal Oscillation (PDO), the Quasibienniel Oscillation just to name a few....all of these highlight troughs and ridges in various configurations from the Pacific to the Atlantic and to the poles. It's the various combinations of these oscillations that give us particular weather patterns. Sometimes a positive phase of one along with a negative phase of another delivers potent east coast storms....but perhaps the opposite will slam the west coast with storms...and that's just with only two variables, let alone a combination of all the others. Perhaps one will enhance a particular pattern or even cancel it out. It's fluid and always changing--sort of like my analogy of the Rubiks Cube in another thread. They've been occuring for thousands/millions of years...it's just we're now recognizing these patterns, assigning them cool acronyms, and trying to gauge their frequency so we can identify future patterns.

Hope that helps.

Cheers

From what I can deduce, discussion of them is limited to describing their current state. "It is what it is."

It does not appear they can be used for forecasting, since you don't know what they are "going to do next". Correct?

 

[WinnChill]

Well, they are forecast-able (not even sure that's a word) to a degree. We can see from long range forecasting models showing these patterns setting up or changing so we can determine which particular oscillation will effect us with more/less stormy conditions. Here's a link for example that I use for some of these oscillation forecasts....just one tool in the forecasting toolkit.

 

[bigbog]

Think it's definitely an important way of looking at the puzzle...Getting as many different objects help, at least, to get a grip on the interaction processes going on for modeling...imho.