# Wobbles in the Barriers: Arctic Oscillation (4)

By: Dr. Ricky Rood , 4:22 PM GMT on October 14, 2013

Wobbles in the Barriers: Arctic Oscillation (4)

This is a continuation of my series on the Arctic Oscillation / North Atlantic Oscillation. Links to background material and previous entries are at the end.

In the last entry I suggested that if you were on a bridge overlooking a swiftly flowing creek then you would notice that twigs floating in the water did not move across the current. They are carried downstream along the edge of the current. The purpose of that comparison was to demonstrate how fast-moving, concentrated flows have the effect of isolating one side of the creek from the other. This is true in the creek, and it is also true about jet streams in the atmosphere.

One way to understand the Arctic Oscillation is to think of it as the variation of an atmospheric jet stream. For the Arctic Oscillation the jet stream of interest is the southern edge of vortex of air that circulates around the North Pole (see previous entry). Air inside the vortex often has characteristics different from air outside it. Intuitively for the Arctic, there is colder air on the side toward the pole. If you look at trace gases, like ozone, they are different across the edge of the vortex. The takeaway idea is that the edge of the vortex is a barrier. It’s not a perfect barrier, but the air on one side is largely separated from the air on the other side. In this blog, I describe the difference between a strong and a weak vortex – which is the same as the difference between the positive and negative phases of the Arctic Oscillation and the North Atlantic Oscillation.

Figure 1: This figure is from the point of view of someone looking down from above at the North Pole (NP). Compare this perspective to Figure 1 in previous blog. This represents a strong, circular vortex centered over the pole, which encloses cold air, represented as blue. The line surrounding the cold air is the jet stream or the edge of the vortex.

Figure 1 shows an idealized schematic of the North Pole as viewed from above. This is the strong vortex case, when there is exceptionally low pressure at the pole. Low pressure is associated with counterclockwise rotation in the Northern Hemisphere. This direction of rotation is called cyclonic. This strong vortex case is the positive phase of the Arctic Oscillation. During this phase, the vortex aligns strongly with the rotation of the Earth, and there are relatively few wobbles of the edge of the vortex – the jet stream. I drew on the figure two points, X and Y. In this case, the point X is hot and the point Y is cold. It is during this phase when it is relatively warm and moist over, for example, the eastern seaboard of the United States.

Figure 2 compares a strong vortex and a weak vortex. In both cases, the circulation around a central point is counterclockwise or cyclonic. However, in the weak vortex case, the vortex does not align as strongly with the rotation of the Earth and there are places where the edge of vortex extends southwards. The vortex appears displaced from the pole; it is not centered over the pole.

Figure 2: Examples of a strong, circular vortex and a weak, more wavy vortex. See text for a more complete description.

Whether the vortex is stronger or weaker is determined by the atmospheric pressure at the pole. In the winter, an important factor that determines the circulation is the cooling that occurs at polar latitudes during the polar night.

What determines the waviness or wobbles at the edge of this vortex? The structure at the edge of vortex is strongly influenced by several factors. These factors include the structure of the high-pressure centers that are over the oceans and continents to the south of jet stream. One could easily imagine a strong high-pressure center over, for example, Iceland, pushing northward at the edge of the vortex. This might push a lobe of air characteristic of the middle latitude Atlantic Ocean northward. Since the edge of the vortex is something of a barrier, this high-pressure system would distort the edge of the vortex and, perhaps, push the vortex off the pole. This would appear as a displacement of the vortex and its cold air over, for example, Russia. If the high grew and faded, then this would appear as wobbles of the vortex.

Other factors that influence the waviness at the edge of the vortex are the mountain ranges and the thermal contrast between the continents and the oceans. The impact of mountains is easy to understand. Returning to the creek comparison used above, the mountains are like a boulder in the stream. The water bulges around and over the boulder; the air in the atmosphere bulges around and over the mountain ranges. The Rocky Mountains in the western half of North America are perfect examples of where there are often wobbles in the atmospheric jet stream.

Figure 3: This figure is from the point of view of someone looking down from above at the North Pole (NP). This represents a weak, wavy, wobbly vortex displaced from the pole. The vortex encloses cold air, represented as blue. The line surrounding the cold air is the jet stream or the edge of the vortex. (definition of vortex)

Figure 3 shows an idealized schematic of the North Pole as viewed from above. This is the weak vortex case, when the low pressure at the pole is not as low as average and the pressure is much higher than the strong vortex case of Figure 1. This weak vortex case is the negative phase of the Arctic Oscillation. During this phase, the alignment of the vortex with the rotation of the Earth is less prominent, and there are wobbles of the edge of the vortex – the jet stream. In this case, the point X is cold and the point Y is hot. It is during this phase where it is relatively cool and dry (but potentially snowy) over, for example, the eastern part of the United States.

These figures help to explain the prominent signal of the Arctic Oscillation discussed in the earlier entries (specifically, this blog). That is, when the vortex is weak and wobbly, then there are excursions of colder air to the south and warmer air to the north. This appears as waviness and is an important pattern of variability - warm, cold, warm, cold.

The impact of the changes in the structure of edge of the vortex does not end with these persistent periods of regional warm and cold spells. The edge of the vortex or the jet stream is also important for steering storms. Minimally, therefore, these changes in the edge of the vortex are expected to change the characteristics of how storms move. Simply, if the edge of the vortex has large northward and southward extensions, then storms take a longer time to move, for example, across the United States from the Pacific to the Atlantic Oceans. In the positive phase of the Arctic Oscillation they just whip across. In the negative phase, the storms wander around a bit. A more complete discussion of this aspect of the role of the Arctic Oscillation will be in the next entry. (Note use of dramatic tension and the cliffhanger strategy of the serial.)

r

Previous entries:

Barriers in the Atmosphere
Behavior
Definitions and Some Background

August Arctic Oscillation presentation

CPC Climate Glossary “The Arctic Oscillation is a pattern in which atmospheric pressure at polar and middle latitudes fluctuates between negative and positive phases.”

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

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##### 655. schwankmoe
 Quoting 649. PensacolaDoug:I'm done. I have work to do. That's what happened. If there is another explanation. So be it. It's enough to make any reasonable person wonder.so first it's utter proof, now it's 'well it makes you wonder'?
Member Since: December 31, 1969 Posts: Comments:
##### 654. schwankmoe
 Quoting 650. ncstorm:Doug is right..the thread is there for everyone to view..You guys had a discussion in this same thread about fake handles from AGW deniers and look what the cat caught..if another blogger who is labeled a denier had done that, you guys would have been all over that like white on rice..Thanks Doug..not over one word in one post, no.
Member Since: December 31, 1969 Posts: Comments:
 Quoting 652. BrownWeather:JB. Are you kidding me? Doug? Why are you so obsessed with JB. Even in Naples--South Florida for Pete's Sake--he can't predict the weather correctly. And were talking all year round. Not very difficult.Time for a changing of the guard, no? ;-)Huh? Yer loosin the bubble there friend.
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##### 650. ncstorm
 Quoting 647. PensacolaDoug:Dealwithit was talking to Nea.JL answered.Doug is right..the thread is there for everyone to view..You guys had a discussion in this same thread about fake handles from AGW deniers and look what the cat caught..if another blogger who is labeled a denier had done that, you guys would have been all over that like white on rice..Thanks Doug..
Member Since: December 31, 1969 Posts: Comments:
 I'm done. I have work to do. That's what happened. If there is another explanation. So be it. It's enough to make any reasonable person wonder.
Member Since: December 31, 1969 Posts: Comments:
 Quoting 645. GiovanniDatoli:Ah, Dougie. Still circumventing the truth. Still inclined to listen to Fox News, Glenn Beck, Rush, JB, and the whole circus parade of clowns...Still understanding climate change and the anthropogenic effects of CO2 from the likes of WUWT? ;-)The truth is--and has been documented by NASA and thousands of climate scientists is that the globe is warming, and rapidly. And the global extremes that are occurring will only become that of, more extreme. Sure, we can buy into the never-ending propaganda of what Big Oil and the fossil fuel industry wants you to believe. But I, tend to believe science, and also have a genuine interest in protecting the globe from harm others seem to want to impose. The rest is simply banter from denialists that seems to be falling upon deaf ears. Nothing more, nothing less.Huh? Lighten up Francis...
Member Since: December 31, 1969 Posts: Comments:
 Quoting 643. Birthmark:What makes it more likely than a Lonergan/DealWithIt, um, discussion further upthread or even on a different day?Dealwithit was talking to Nea.JL answered.
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##### 644. schwankmoe
 Quoting 632. ScottLincoln:Ok, so if I understand correctly, you are saying that your "proof" (your words, not mine) is that a different person replied to a back-and-forth involving Neapolitan with a "I" instead of a "he?"Although evidence for your claim, perhaps, I'm not sure I agree that it is "proof." Let me look back on those few posts.On a side note...if that is what is enough for "proof" in your book for something, then I'm even more at a loss for why you have such trouble coming to terms with climate science.yeah, it's...well, it's "I" instead of "he" in one post. not really a whole lot. anything's possible but that aint very much.OTOH, it's SOP for a lot of people on internet forums to intentionally deny the humanity of the people they disagree with. oh, i don't like what you have to say, therefore you're not an actual person. rubs me the wrong way given the fact that my own people were considered 'non-humans' at one point for little reason other than hatred.
Member Since: December 31, 1969 Posts: Comments:
 Quoting 640. Birthmark:That is not the only possible explanation. Did you check back in the thread to see what, if any, interactions took place between DealWithIt and John Lonergan? If not, it might be worth a look since you seem interested.A link to the thread might help bolster your position, too.It's the most likely explanation.
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##### 639. ScottLincoln
 Quoting 637. PensacolaDoug:You don't believe those posts are real?Trust but verify. It's what most people lack when talking climate science.I think I found the thread. One of the posters has been banned since.
 It stinks alright; stinks of desperation on your part. Seems like a common theme these days for folks on the far right fringe - if you can't win an argument on the merits, try taking a hostage or throwing some slime to get your wayThat the way of the left. Try again.
Member Since: December 31, 1969 Posts: Comments:
 Quoting 635. ScottLincoln:Still looking for the series of posts. So far I've instead found a cherry picked plot of snow cover changes that ignores May through October.You don't believe those posts are real?
Member Since: December 31, 1969 Posts: Comments:
 Quoting 634. TheDevilsAdvocate:It stinks alright; stinks of desperation on your part. Seems like a common theme these days for folks on the far right fringe - if you can't win an argument on the merits, try taking a hostage or throwing some slime to get your way. Just wondering - if someone used some "evidence" as lame as what you present in comment #629 to try to impugn your integrity, would you think it fair?How would you explain it?
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##### 635. ScottLincoln
 Quoting 633. PensacolaDoug:Read it and decide for yourself if it passes the smell test. It's my contention that Nea got his accounts mixed up and answered as himself under the JohnLonergan sock puppet.Still looking for the series of posts. So far I've instead found a cherry picked plot of snow cover changes that ignores May through October.
 Read it and decide for yourself if it passes the smell test. It's my contention that Nea got his accounts mixed up and answered as himself under the JohnLonergan sock puppet.
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##### 632. ScottLincoln
 Ok, so if I understand correctly, you are saying that your "proof" (your words, not mine) is that a different person replied to a back-and-forth involving Neapolitan with a "I" instead of a "he?"Although evidence for your claim, perhaps, I'm not sure I agree that it is "proof." Let me look back on those few posts.On a side note...if that is what is enough for "proof" in your book for something, then I'm even more at a loss for why you have such trouble coming to terms with climate science.
##### 631. ScottLincoln
 http://www.openculture.com/2013/10/noam-chomsky-d erides-911-truthers.htmlReplying to a "911 Truther:""In fact, you%u2019re right that there%u2019s a consensus among a miniscule number of architects and engineers. They are not doing what scientists and engineers do when they think they%u2019ve discovered something. What you do is write articles in scientific journals, give talks at the professional societies, go to the civil engineering department at MIT or Florida or wherever you are, and present your results, then proceed to try to convince the national academies, the professional society of physicists and civil engineers, the departments of the major universities, that you%u2019ve discovered something.""There happen to be a lot of people around who spend an hour on the internet and think they know a lot [about] physics, but it doesn%u2019t work like that. There%u2019s a reason there are graduate schools in these departments."
##### 630. schwankmoe
 Quoting 627. ScottLincoln:If you respect it, then please, by all means, follow through, Douglas.alright! (rubs hands together, waits for evidence).
Member Since: December 31, 1969 Posts: Comments:
Member Since: December 31, 1969 Posts: Comments:
##### 628. ScottLincoln
 Quoting 518. overwash12: It's just nature,been going on for thousands of years! Sunspots,Volcanoes,play a role in our climate still to this day,no matter what anybody says!Of course they do. Who says that they dont?
##### 627. ScottLincoln
 Quoting 625. PensacolaDoug:Now that post made sense. I can respect "put up or shut up" as I've used the phrase myself on numerous occasions.If you respect it, then please, by all means, follow through, Douglas.
 Quoting 623. TheDevilsAdvocate:Seems like you're the one saying stuff, Doogie - 6 comments worth by my count. If that ain't obsession, I don't know what is. Unfortunately for you, just saying stuff don't add up to much in this world. I do expect if you had some "evidence" we'd have seen it long ago. Put up or shut is what we say where I come from.Now that post made sense. I can respect "put up or shut up" as I've used the phrase myself on numerous occasions.
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##### 624. Xandra
 The deniers prove our point again (3)[...] The deniers remind me of people who don't know how to speak a foreign language so they just yell loudly in English. They don't speak Science but they know how to yell loudly or write many words. But it isn't what they say or how they say it that matters. it's what they don't say that matters most of all.The deniers don't have a single shred of evidence to support anything they say ever. They just boast and assert and pontificate. I can imagine the jurors leaning forward in the jury box waiting for the proof that never comes. They got nothin' and they seem to be the only ones who don't realize it. They are clowns at a circus and yet they have no clue.Every post of a denier proves my point better than anything I could ever write. They never back up their claims with scientific evidence from trusted sources. Their only source is themselves or other deniers. And while that is good enough in the fantasy bubble of Fox News and Rush Limbaugh and the Tea Party, the rest of us live in a real world that is undergoing rapid, cataclysmic change that is unprecedented in geologic and climatic history.The deniers seem to exist for two reasons. Comic relief and obstruction. We may not survive the changes to come. But we will not lack for entertainment.
 Quoting 621. TheDevilsAdvocate: Not nearly as disturbing as your rather unhealthy obsession with certain folks on this blog. Closely related to Gore Derangement Syndrome, I think.If you got a point to make Doogie, spit it out. Otherwise maybe you should just crawl back under your rock. I'm not the one pretending to be other people.No matter what you say. I have integrity. Your post proves, you don't.
Member Since: December 31, 1969 Posts: Comments:
 Quoting 611. JohnLonergan:There is a clinical name for this affliction, it's called Gore Derangement Syndrome(GDS).There's a clinical name for your syndrome as well.MPDCVMultiple Personality Disorder-Cyber Variant.
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 I can only prove the one but it stands to reason if you got 1 then it's likely you've got more.
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 Re 611: Making a post then answering yourself is a little disturbing.
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 You guys are big on evidence right?
Member Since: December 31, 1969 Posts: Comments:
 Quoting 614. JohnLonergan:Them Gamma Shine Events sure can ruin your day.Why are you still using this sock puppet Nea?I can prove you're one and the same. Do you deny it?It is a fair question. It goes to your credibility.
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##### 614. JohnLonergan
 Quoting 613. Patrap:This would release an enormous amount of radioactivity, which Arnie Gundersen has referred to as a Gamma Shine Event without precedence, and Dr. Christopher Busby has deemed an "Open-air super reactor spectacular".Them Gamma Shine Events sure can ruin your day.
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##### 613. Patrap
 Radioactive Water Leaking From Fukushima: Why Millions Of Lives Are At StakeIn lieu of the Japanese government doing the right thing and finally coming clean about the epic environmental catastrophe that is Fukushima, which it hopes to simply dig under the rug even as the inconvenient reality gets worse and thousands of tons of radioactive water make their way into the ocean, one is forced to rely on third-party sources for information on this tragedy. We present a useful primer from Scientific American on Fukushima "water retention" problem and "what you need to know about the radioactive water leaking from Japan's Fukushima nuclear plant into the Pacific Ocean."Once the integrity of the pool is compromised that will likely lead to more criticalities, which then can spread to other fuel. The heat from this reaction would weaken the structure further, which could then collapse and the contents of the pool end up in a pile of rubble on the ground. This would release an enormous amount of radioactivity, which Arnie Gundersen has referred to as a Gamma Shine Event without precedence, and Dr. Christopher Busby has deemed an "Open-air super reactor spectacular".
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##### 612. JohnLonergan
 Quoting 608. Xulonn:Do you really thing these protesters induced 'terror" into anyone? What a joke!Eek! Eek! I'm terrified for my life. Someone just scattered glitter in my office!They remind me of James Hanson, Thoreau, Ghandi and MLK, not terrorists.
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##### 611. JohnLonergan
 Quoting 603. Neapolitan:Your obsession with/attraction for Mr. Gore strikes some as more than a little creepy. Did you know that? Did you also know that Gore hasn't been elected to public office since November of 1996? Think about that: you're devoting so much of your time and energy thinking about, and being hurt by, someone who hasn't been elected to any post that would put him into a position to set public policy for more than 6,000 days.Six. Thousand. Days.You know, if a girlfriend dumps you, it's okay to mope about the house for a few days or weeks, to feel a little blue, a little angry at the object of your affection who's moved on. But if you're still feeling that same way--just as passionate, just as hurt--6,000 days later, professional intervention may be called for...There is a clinical name for this affliction, it's called Gore Derangement Syndrome(GDS).
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##### 610. schwankmoe
 Quoting 608. Xulonn:Do you really thing these protesters induced 'terror" into anyone? What a joke!Eek! Eek! I'm terrified for my life. Someone just scattered glitter in my office!i hear hamas does the same thing.
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##### 609. Xulonn
 Quoting 592. Neapolitan:Amazing, ain't it? Record cold snapping to record heat, back and forth at a moment's notice. I think Dr. Masters refers to it as climate change-induced weather whiplash. And that's about as succinct a description as I can think of. Wouldn't you agree? So thanks for posting that...Iceagecoming demonstrates by his comments that her/she despises Dr. Masters and thinks the "good doctor," as many denialists call him at his blog, is an idiot!
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##### 608. Xulonn
 Quoting 588. iceagecoming:Real climate Alarmists (eco-terrorists) on the job.PortsmouthBy JASON SCHREIBERUnion Leader CorrespondentThis photograph from the website of the Trans and Womyn's Action Camp shows protestors bound together in the office of Irving Oil in Portsmouth Monday morning. PORTSMOUTH - Five activists protesting shale gas exploration in Canada were arrested Monday morning after refusing to leave the local corporate offices of Irving Oil Corp.Police responded to Irving's office at 190 Commerce Way just before 11 a.m. after the company called to report the activists were on the property and had made their way inside the building.Police said about 20 people entered the Irving building and refused to leave when asked by management. They caused a disturbance by throwing glitter and other items inside the building and blowing whistles, police said.Four of the activists locked themselves together by placing their arms in a steel pipe and chaining them to a bar inside, according to Deputy Police Chief Corey MacDonaldThe four attached to the pipe contraption remained seated in a circle on the floor in the lobby area.Do you really thing these protesters induced 'terror" into anyone? What a joke!Eek! Eek! I'm terrified for my life. Someone just scattered glitter in my office!
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##### 607. schwankmoe
 Quoting 602. Patrap:Fukushima readies for dangerous operation to remove 400 tons of spent fuelPublished time: October 23, 2013 19:34 Edited time: October 24, 2013 11:53“The worst-case scenario could play out in death to billions of people. A true apocalypse,” Consolo said. LOLWUT?
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