From the Georgia Institute of Technology
‘Stadium waves’ could explain lull in global warming
One of the most controversial issues emerging from the recent Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) is the failure of global climate models to predict a hiatus in warming of global surface temperatures since 1998. Several ideas have been put forward to explain this hiatus, including what the IPCC refers to as ‘unpredictable climate variability’ that is associated with large-scale circulation regimes in the atmosphere and ocean. The most familiar of these regimes is El Niño/La Niña, which are parts of an oscillation in the ocean-atmosphere system. On longer multi-decadal time scales, there is a network of atmospheric and oceanic circulation regimes, including the Atlantic Multidecadal Oscillation and the Pacific Decadal Oscillation.
A new paper published in the journal Climate Dynamics suggests that this ‘unpredictable climate variability’ behaves in a more predictable way than previously assumed.
The paper’s authors, Marcia Wyatt and Judith Curry, point to the so-called ‘stadium-wave’ signal that propagates like the cheer at sporting events whereby sections of sports fans seated in a stadium stand and sit as a ‘wave’ propagates through the audience. In like manner, the ‘stadium wave’ climate signal propagates across the Northern Hemisphere through a network of ocean, ice, and atmospheric circulation regimes that self-organize into a collective tempo.
The stadium wave hypothesis provides a plausible explanation for the hiatus in warming and helps explain why climate models did not predict this hiatus. Further, the new hypothesis suggests how long the hiatus might last.
Building upon Wyatt’s Ph.D. thesis at the University of Colorado, Wyatt and Curry identified two key ingredients to the propagation and maintenance of this stadium wave signal: the Atlantic Multidecadal Oscillation (AMO) and sea ice extent in the Eurasian Arctic shelf seas. The AMO sets the signal’s tempo, while the sea ice bridges communication between ocean and atmosphere. The oscillatory nature of the signal can be thought of in terms of ‘braking,’ in which positive and negative feedbacks interact to support reversals of the circulation regimes. As a result, climate regimes — multiple-decade intervals of warming or cooling — evolve in a spatially and temporally ordered manner. While not strictly periodic in occurrence, their repetition is regular — the order of quasi-oscillatory events remains consistent. Wyatt’s thesis found that the stadium wave signal has existed for at least 300 years.
The new study analyzed indices derived from atmospheric, oceanic and sea ice data since 1900. The linear trend was removed from all indices to focus only the multi-decadal component of natural variability. A multivariate statistical technique called Multi-channel Singular Spectrum Analysis (MSSA) was used to identify patterns of variability shared by all indices analyzed, which characterizes the ‘stadium wave.’ The removal of the long-term trend from the data effectively removes the response from long term climate forcing such as anthropogenic greenhouse gases.
The stadium wave periodically enhances or dampens the trend of long-term rising temperatures, which may explain the recent hiatus in rising global surface temperatures.
“The stadium wave signal predicts that the current pause in global warming could extend into the 2030s,” said Wyatt, an independent scientist after having earned her Ph.D. from the University of Colorado in 2012.
Curry added, “This prediction is in contrast to the recently released IPCC AR5 Report that projects an imminent resumption of the warming, likely to be in the range of a 0.3 to 0.7 degree Celsius rise in global mean surface temperature from 2016 to 2035.” Curry is the chair of the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology.
Previous work done by Wyatt on the ‘wave’ shows the models fail to capture the stadium-wave signal. That this signal is not seen in climate model simulations may partially explain the models’ inability to simulate the current stagnation in global surface temperatures.
“Current climate models are overly damped and deterministic, focusing on the impacts of external forcing rather than simulating the natural internal variability associated with nonlinear interactions of the coupled atmosphere-ocean system,” Curry said.
The study also provides an explanation for seemingly incongruous climate trends, such as how sea ice can continue to decline during this period of stalled warming, and when the sea ice decline might reverse. After temperatures peaked in the late 1990s, hemispheric surface temperatures began to decrease, while the high latitudes of the North Atlantic Ocean continued to warm and Arctic sea ice extent continued to decline. According to the ‘stadium wave’ hypothesis, these trends mark a transition period whereby the future decades will see the North Atlantic Ocean begin to cool and sea ice in the Eurasian Arctic region begin to rebound.
Most interpretations of the recent decline in Arctic sea ice extent have focused on the role of anthropogenic greenhouse gas forcing, with some allowance for natural variability. Declining sea ice extent over the last decade is consistent with the stadium wave signal, and the wave’s continued evolution portends a reversal of this trend of declining sea ice.
“The stadium wave forecasts that sea ice will recover from its recent minimum, first in the West Eurasian Arctic, followed by recovery in the Siberian Arctic,” Wyatt said. “Hence, the sea ice minimum observed in 2012, followed by an increase of sea ice in 2013, is suggestive of consistency with the timing of evolution of the stadium-wave signal.”
The stadium wave holds promise in putting into perspective numerous observations of climate behavior, such as regional patterns of decadal variability in drought and hurricane activity, the researchers say, but a complete understanding of past climate variability and projections of future climate change requires integrating the stadium-wave signal with external climate forcing from the sun, volcanoes and anthropogenic forcing.
“How external forcing projects onto the stadium wave, and whether it influences signal tempo or affects timing or magnitude of regime shifts, is unknown and requires further investigation,” Wyatt said. “While the results of this study appear to have implications regarding the hiatus in warming, the stadium wave signal does not support or refute anthropogenic global warming. The stadium wave hypothesis seeks to explain the natural multi-decadal component of climate variability.”
Marcia Wyatt is an independent scientist. Judith Curry’s participation in this research was funded by a Department of Energy STTR grant under award number DE SC007554, awarded jointly to Georgia Tech and the Climate Forecast Applications Network. Any conclusions or opinions are those of the authors and do not necessarily represent the official views of the sponsoring agencies.
CITATION: M.G. Wyatt, et al., “Role for Eurasian Arctic shelf sea ice in a secularly varying hemispheric climate signal during the 20th century,” (Climate Dynamics, 2013). http://link.springer.com/article/10.1007/s00382-013-1950-2#page-1
Mike Borgelt (October 11, 2013 at 1:23 pm) wrote:
“Over at Jo Nova’s site one commenter mentioned that Judith Curry and her husband run a consultancy advising companies on climate change mitigation. This all would just seem to be advertsing for business by raising her profile. As ever, follow the money.”
I have always suspected that this is what’s behind the relentlessly pushed “uncertainty” narrative she incessantly drives. The “internal” narrative is strictly ruled out (in the mathematical sense) by earth rotation & global atmospheric angular momentum records constrained by the laws of large numbers & conservation of angular momentum (what idiot goes up against that combo? = plain stupid).
Confused clients might naturally feel a need (“must haves” in retail lingo) to buy more outlook scenarios (yes I have a lot of diverse private sector business experience, including with underhanded sales tactics). I wonder if anyone has explored the pricing structure. For example, do clients pay more for more scenarios &/or more detailed contingency tables?
Very comically — in an entertaining display of pure hypocrisy — the passionate “deep uncertainty” advocate is stubbornly (and foolishly) certain about one thing: that natural climate variations are “internal”. Quite revealing. I hope everyone is capable of independently realizing that no stronger support for the IPCC reaching it’s 100th birthday could possibly be shown.
Marcia Wyatt is an independent in the strongest sense of the word. I sternly advise commentators to NOT attempt to conflate Marcia’s sensible explorations & contributions with Judy Curry’s power politics &/or business antics.
The alliance looks practical; there’s something different in it for each of them. Marcia’s passion is exploring and understanding nature. (Some of you may not be aware of her background in geology.) I might be willing to feign more respect for Judy if she would simply drop the single strictly indefensible word “internal”. If she stubbornly holds on to it, THAT will indeed be deeply informative about exactly what kind of a person we’re dealing with.
Friends:
I write in defence of Judith Curry. Some people here have accused her of being dishonest in her climate views. I disagree with those accusations.
For a time I posted in threads on her blog and only desisted when I suffered persistent stalking from a troll which became intolerable. During that time she used her blog to discern views of climate science which would be useful in formulating her thoughts in preparation for her making a presentation to a US Congressional Hearing.
I made a long post on her blog which explained what I perceive to be the problems of climate science. Simply, I argued and explained that academic research lacks the oversight and accountability of commercial and industrial research with resulting severe flaws in the quality and error correction of the products of ‘climate science’. Her written presentation to that Hearing contained a section which was almost verbatim the same as my post.
I have consistently disputed AGW since the early 1980s. But Judith Curry – who accepts AGW – was willing to accept my views, to adopt them, and to present them to the US Congress as being valid criticism of climate science by “climate change skeptics”.
That is not the behaviour of a “political hack”, a “fifth columnist” or a dishonest scientist. It is the behaviour of a ‘seeker after truth’ who is willing to be convinced by sound arguments from anyone.
Richard
This authoritative work on the internal nonlinear cycles of ocean-driven climate has had an illuminating effect on the climate debate especially here at WUWT. Its as if a few large rocks have been rolled and a crowd of creepy bugs unaccustomed to the light are scurrying here and there.
Two groups are unhappy with the illucidation of natural oscillation patterns in climates. One is the AGW community, crowding anxiously to Judith Curry’s site, seeking reassurance that they can still have their CO2 heating catastrophe. The other group agitated by the harsh glare of this strengthening oscillation paradigm is WUWT’s star-gazers alliance, the motley crew of astrophysical wiggle-weavers and astrologers. Internal climate oscillation to them is like radiodating and palaeontology to 6-day creationists.
So the real climate debate is not between AGW and the rest – instead it is between emerging clarity and reason about internal oceanic climate oscillation, on the one hand, and a die-hard alliance of watermelon AGW doom-mongers and the star-gazers on the other. Both of whom require a climate system impossibly passive to external forcing, and are in denial of the basic science of complex systems.
Nice post richardscourtney, I concur.
Marcia Wyatt made a comment either here or at Judiths blog that solar influences and others were considered in her paper but the reviewers asked that they be removed for consideration in a future work.
Stephen Wilde says:
October 11, 2013 at 2:15 pm
One can only achieve those characteristics if there is another, longer solar induced periodicity upon which the stadium wave is superimposed.
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There are several solar influences of varying periods, why would you assume that J Curry or M Wyatt have not considered them?
Some of the above comments appear to arrive at some very negative conclusions about the motives of the 2 authors. I have read the above article and I can see no validity for assuming such negative stances.
Stephen Wilde says: “However, as I pointed out over at Climate etc. there is still the issue of the MWP, LIA, Current Warm Period and that phase to phase temperature stepping that shows up in the observations.”.
Spot on. The paper addresses the minor variations – the ~60-year ‘cycle’ – and avoids the main game. It does go further than identifying the fact that the ~60-year ‘cycle’ exists, and it really is a step forward for the scientific literature and I expect much of it to prove valuable in future, but the fact is that they don’t know the mechanisms (they suggest some but these need verifying), they don’t know the amplitudes of the cycles, and they don’t know what prevents the cycles from declining. Hence they can’t use it meaningfully in models, and they can’t use any of it for prediction. And it is worth repeating that they were not studying the longer cycles, ie. the ones that really change the climate (MWP, LIA etc), or your ‘temperature stepping’.
“One can only achieve those characteristics if there is another, longer solar induced periodicity upon which the stadium wave is superimposed.”.
Yes, but I am wary of the ‘only’ and the ‘solar induced’.
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richardscourtney – I too would like to commend your defence of Judith Curry.
goldminor, asks “There are several solar influences of varying periods, why would you assume that J Curry or M Wyatt have not considered them? ”. The answer is in Marcia Wyatt’s comment (October 10, 2013 at 10:49 pm) : “Unfortunately, we had to drop solar from this paper, postponing to a future paper‘.
Kudos to Marcia Wyatt and Judith Curry.
I could not finish reading this thread because of all the nutballs that are unable to appreciate what it she has done.
Gilbert, I agree. There have been entirely too many nasty, non-substantive, personal attacks on this thread. Sadly, an opportunity for reasoned discourse wasted by foam-at-the-mouthers with nothing to say.
This blog is going to end up in the toilet if some of this doesn’t get reigned in.
Actually, in this thread, I first suggested that word. It has been used several times before this thread by others on this site. I’m posting now to suggest a couple of refinements in its spelling-usage:
Plateau’d = stalled, halted, paused.
Plateau-ing = stalling, halting, pausing.
– – – – – – – – –
rogerknights (& dbstealey & Colorado Wellington & Pochas),
I suggest the more objective terminology to use is that which Richard Lindzen recently uses. He called the ~17 year GASTA time series period ‘not warming’.
It is elegant and not misleading in any way.
John
dalyplanet says (October 11, 2013 at 6:41 pm) wrote:
“Marcia Wyatt made a comment either here or at Judiths blog that solar influences and others were considered in her paper but the reviewers asked that they be removed for consideration in a future work.”
You don’t need to wait for a future publication of someone else to learn for yourself. Just gather up all of the solar reconstructions (some of which primarily indicate solar properties other than TSI) and do the analyses yourself. If you’re functionally numerate, you’ll easily see within an hour why this did NOT make publication.
It’s easy enough to re-conceptualize to achieve consistency with observed earth rotation & atmospheric angular momentum.
There’s a lot more to this story, but restraint is the most important human capacity…
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@ur momisugly phlogiston
Like it or not your models aren’t free to violate the laws of large numbers & conservation of angular momentum. Your models NEED to be able to reproduced well-constrained statistical properties of earth rotation & global atmospheric angular momentum records. THIS IS NON-NEGOTIABLE.
Looks like real science to me. Hypothesis developed using statistical analysis and a clear prediction which can be measured is the outcome.
The test of their theory is the next 30 years. Well, it can certainly be refuted in that time period, but it may survive longer than that.
How about doing the same for a multicentennial timescale, or are the drivers of that beat not yet known yet??
There are a lot of commentators who don’t seem to realize that they’ve already had a few years to familiarize themselves with the core insight emphasized in the new (2013) paper.
See figure 4 here:
Wyatt, M.G.; Kravtsov, S.; & Tsonis, A.A. (2011). Atlantic Multidecadal Oscillation and Northern Hemisphere’s climate variability. Climate Dynamics. doi: 10.1007/s00382-011-1071-8.
For those who don’t have a copy of the 2011 paper, its figure 4 also appears as figure 1 on this poster: https://pantherfile.uwm.edu/kravtsov/www/downloads/Presentations2010-2011/AMO_AGU10.pdf
So, it’s the sun, somehow. I don’t worry; Marcia Wyatt’s on the case.
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Paul Vaughan says:
October 11, 2013 at 2:19 pm
I do not agree with your post but I do understand it. I doubt that more than a few understand it because you do not clarify the importance of the word ‘internal’ as it appears in Curry’s work or posts. I too believe that the word ‘internal’ is very important in the currently raging debate but it would be foolish for me to attempt to state your view on the matter.
richardscourtney says:
October 11, 2013 at 2:52 pm
Good for you, Richard. I cannot fathom why anyone would distrust Judith Curry. She is as old school as it gets, a “two-handed scientist.”
Steve Garcia says:
October 11, 2013 at 12:30 am
“We are STILL coming out of the LIA, so the climate is doing what climate after ice ages does: IT WARMS UP OVER TIME. We are still in the middle of that warming. When will it end? Who knows?”
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And when will the proponents of CAGW admit that they have “hijacked” all of the interglacial “warming up” beginning with their 1880 Temperature Records?
“Who know?” My guess is they never will admit to it.
And given the fact that the proponents of CAGW can’t explain the “pause” in their calculated “percentage” increases/decreases in Average Surface Temperatures ….. it won’t surprise me if they switch to a “percentile” ranking for all of their future Surface Temperature claims.
That’s how Public School Educators solved their “pausing” problems.
Mike Jonas says:
October 11, 2013 at 8:01 pm
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Thanks for pointing out her comment. I had skipped through a portion of the comments.
Carrick says:
October 11, 2013 at 9:55 pm
The people who are really saying nothing, “the nutballs” are those claiming the AGW debates are motivated by “science” not opinion. Largely political opinion.
Psychology is a “science” as well, I doubt most people serious in the field would contrive a theory for massive global authority and regulations based on a non-empirical “idea” in psychology. Yet climate science consensus is far closer to such a reality and yes Dr. Curry is a net supporter of such authority.
Is it speculation why a paper affirming models and warming theory is issued a week after she states the IPCC should be “put down”? Of course it is. Is there more to the paper than what I and others are focusing on? Of course. Could it all be random coincidence in the timing of events? Perhaps. Is it speculation Dr. Curry plays both sides like a harp? No, that’s pretty well confirmed by many observations. There are of course many sides and opinions other than the pro vs. anti AGW agenda’s. There are many subset warmers like Lomborg or Curry. There are many shades of warmists and skeptics alike. Do I think the term “the Pause” is anything other than another politically motivated concoction? No, I don’t.
Unless other evidence is presented I don’t think “following the money” reflects Dr. Curry at all. Sure they might have a financial benefits in “uncertainty” but I have no doubt this is her actual belief. Dr. Curry believes in central authority on climate “policy”, it’s her right and she net wins economically in such a system but I suspect she would believe it even if she was going to lose. I think many academics define themselves internally on their core beliefs. That they managed to make a buck in the process isn’t primary at the higher end. I could say as much about Al Gore who is an actual climate hustler and scammer (go review the Chicago carbon exchange history and insider sales before bankruptcy), there is control and money. AGW is largely a political belief system, it’s about control. Money might be a perk but not the main event for many.
At times, Dr. Curry acts like a foil to hardline AGW advocates, that are all too real. She also offers aid and assistance to them by diffusing essentials of the climate debate. Creating false equivocations about the sides and what is core about the AGW movement. Her own politics, Obama donor, are carefully minimized and that preserves her influence on many skeptical groups. Like it or not Dr. Curry has a place in the current debate and she exercises influence through her statements. She’s is at least a former consensus insider to the annoyance of current consensus advocates. People have every right to question her statements and actions and more importantly the carefully honed ambiguity of her imagined moderation, particularly from the harder line skeptical view. If someone is more passively promoting an agenda does that make it any less real? I’m sure many AGW advocates are disgusted by the hard left imagery of Michael Mann, Gavin Schmidt or Jim Hansen and their political and media counter parts Al Gore or the NYTimes. Dr. Curry serves a purpose for them as well. Dr. Curry is soft soap Green/Climate activism at another level. She certainly isn’t a sacred cow or a symbol of academic purity in an ugly time in history. Her middling position and posturing isn’t supported by reason at all. At the core AGW activism is by in large a totalitarian design dressed in many circles as supported by “science”. She’s helped that delusion far more than she has undermined it. So we are left with a false choice, radical leftist AGW and the whimpering Dr. Curry middling to water it down. I say neither because they are on the road to the same goal at different rates..
Thanks. Paul.
Stephen is making very good points with his following observation which I agree with 100%.
STEPHEN SAYS
However, as I pointed out over at Climate etc. there is still the issue of the MWP, LIA, Current Warm Period and that phase to phase temperature stepping that shows up in the observations.
One can only achieve those characteristics if there is another, longer solar induced periodicity upon which the stadium wave is superimposed.
@Nicola Scafetta:
http://chiefio.wordpress.com/2013/01/24/why-weather-has-a-60-year-lunar-beat/
Lunar tides have a 3 x 18.x year repeat of when the same continent or ocean is under the same lunar solar configuration of alignment apogee and above or below ecliptic. It is the metronome.
@ur momisugly Theo Goodwin (October 12, 2013 at 6:38 am)
You reveal clearly that you’re not sufficiently well-informed by the following records:
http://ftp.aer.com/pub/anon_collaborations/sba/aam.ncep.reanalysis.1948.2009
ftp://ftp.iers.org/products/eop/long-term/c04_08/iau2000/eopc04_08_IAU2000.62-now
Ask yourself why people appear determined to go to any length to protect the single word “internal” when these records clarify that it’s a misconception. If you want to try to argue that Judy’s up to naive ignorance rather than malicious deception, that’s fine, but bear in mind that like deception, ignorance is a form of darkness.
Human nature is fascinating. The most fascinating thing I’ve seen during the years I’ve participated in the solar-climate discussion is the vehemence with which people defend this particular darkness, which is literally as wrong as 2+2=5 in a clear-cut black-&-white (not to be deliberately misrepresented as grey) sense.
If Judy is someone you care about, a smarter battle for you to pick would be to help motivate her to complete by the end of October the exercise I outlined for A Lacis.
I’m not here to play games Mr. Goodwin. I’m here to help. 3 years is too long. This exercise should take 20 minutes. If authorities continue to refuse to admit 1+1=2 to the record, we have a literally intolerable breakdown in justice.
You would have to put a lot of money on the table to get me to even think about lying about this, as I would know with certainty that I’d eventually be found out. And even then, I don’t know if I could do it. The only thing I can think of that would make me pretend to go along with an “internal” narrative would be an offer of a guaranteed-secure lifelong position with guaranteed-secure pension at the local university. For that I could probably harmoniously cater to just about any political agenda for strictly practical reasons. Then I could focus on hiking & sea-kayaking and leave all of this noise behind for the rest of my assuredly comfortable days. You might find me projecting born-again-reformation within a few minutes in that case. There you go Mr. Goodwin. I’ve named my price for dark collusion.
Paul Vaughan:
re your post at October 12, 2013 at 10:08 am.
We have been here before. Your campaign of unspecific, untrue and unsubstantiated smears against Judith Curry began on her web site then you transferred it to WUWT where you got the hiding you deserved from several people including me.
The two data files you have again linked in your post I am addressing do NOT indicate anything nefarious about Dr Curry, and despite repeated requests on her web site and on WUWT you have not said how they do.
You have an idea about climate and Dr Curry does not accept it. She also does not agree with me about climate. Her refusal to accept your ideas does not make her a bad person.
Richard
Salvatore Del Prete (October 12, 2013 at 9:54 am)
Sequence matters. Solar-Terrestrial-Climate Weave 1st. MD (multidecadal) is a simple geometric consequence of that. If we try to leap them to centennial without prerequisites for more deeply lucid clarity, we’re attempting to put the cart before the horse. Patience — sometimes assisting education requires a lot of it. God Bless. Get your rest. And be healthy. Thanks for your strategic contributions.