Guest post by Paul Vaughan, M.Sc.
Awhile back I drew attention to temporal patterns shared by the <i>rate of change</i> of solar cycle length (SCL’) and the Atlantic Multidecadal Oscillation (AMO). (See here.)
Correspondence I received later alerted me to the existence of fairly widespread misunderstandings about fundamental differences between the following:
a) Pacific Decadal Oscillation (PDO).
b) North Pacific SST (SST = Sea Surface Temperature).
Some folks, thinking of the PDO, seemed troubled by a <b>mis</b>perception that the Atlantic tracks SCL’ <i>much</i> better than the larger Pacific.
Supplementary graphs may help motivate efforts to overcome misunderstandings:
The North Pacific & Solar Cycle Change
Paul Vaughan, M.Sc. – Sept. 4, 2010
Awhile back I drew attention to temporal patterns shared by the <i>rate of change</i> of solar cycle length (SCL’) and the Atlantic Multidecadal Oscillation (AMO). (See <a href=”http://wattsupwiththat.com/2010/08/18/solar-terrestrial-coincidence/”>here</a>.)
Correspondence I received later alerted me to the existence of fairly widespread misunderstandings about fundamental differences between the following:
a) Pacific Decadal Oscillation (PDO).
b) North Pacific SST (SST = Sea Surface Temperature).
Some folks, thinking of the PDO, seemed troubled by a <b>mis</b>perception that the Atlantic tracks SCL’ <i>much</i> better than the larger Pacific.
Supplementary graphs may help motivate efforts to overcome misunderstandings:
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Interesting finding. I did a brief excursion into PDO and found a ‘correlation’, which of course does not mean causation.
http://www.vukcevic.talktalk.net/PDO.htm
There is also a tenuous link between GMFz and solar activity.
I’m sure it’s interesting, and it’s certainly succinct, but as a layman [?intelligent ditto?], can I request some reduction in jargon?
Is the PDO confined to 20N to 70N?
And might 260E be 100W in ‘real’ Longitude?
> Some folks, thinking of the PDO, seemed troubled by a misperception that the Atlantic tracks SCL’ much better than the larger Pacific.
[Thanks for making it easy to save the bolding and italics!]
This sentence confuses me – it has the PDO (clear), the Atlantic (SST? AMO?), and the Pacific (SST? PDO?).
Its followed by graphs of the North Pacific SST and PDO. No Atlantic. SST or AMO.
What jumps out to me, is how the sea surface temperature graph completely mirrors the global temperature graph – and how those both, in turn, mirror the rate of change of solar cycle length (SCL’) … Aha, this looks like a much-needed primary correlation to solar activity… Now I just want to know how far, when UHI is reasonably subtracted, the global temperature record really mirrors the records of SST and SCL’ and rate of change of Length of Day (LOD’) up to the present time – because if so, surely this is where we really need to look hard, to find/clarify the driving mechanism for climate.
Can anybody produce that chart comparison? Willis?
Re: Autochthony
Regarding wavelet methods: I left some (down-to-earth) notes here.
For a layman’s overview of climate, I can refer you to Bob Tisdale’s website:
http://bobtisdale.blogspot.com/
If Bob is around, perhaps he can point directly to articles most relevant to this thread. (If so, thank you Bob.)
Best Regards.
Echoing Autochthony’s comment – your last two posts have been very interesting and important clues as to astrophysical climate mechanisms; but they are much too short – just a paragraph.
Why? This is not Twitter – you are allowed more than 128 characters.
Just throwing us bones to tantalise us? Why not some introduction and background, and some conclusions and pointers for future work, to sandwich the facts and figures?
Combining the morsels of stark data given in the last two posts, one could draw the odd conclusion that the AMO drives North Pacific SSTs (or vice versa). Clearly it is more likely that both share an astrophysical forcing driver.
Paging Mr. Tisdale…
Why does it appear that SST is leading SCL, particularly 1905 – 1930? A reasonable leap of logic would suggest that some missing third thing is affecting both SST and SCL. Where are all the outer planets while this is going on?
Fascinating, but two caveats. Maybe three:
(1) “Lump matching” over a short run can show order where none exists over the long run.
(2) Derivatives [dx/dt] entail loss of information.
And I don’t immediately see a physical mechanism that would cause SCL variation rate to affect SSTs.
Re: Autochthony and further to this…
Regarding PDO definition:
Data:
ftp://eclipse.ncdc.noaa.gov/pub/ersstv3b/pdo/pdo.1854.latest.situ.v3b.ts
Alternately:
http://jisao.washington.edu/pdo/PDO.latest
I have used the former in this presentation. From the latter page, note the following:
“[…] the PDO index, derived as the leading PC of monthly SST anomalies in the North Pacific Ocean, poleward of 20N. […]”
PC = Principal Component — a concept from multivariate stats. (I may elaborate more on such techniques later…)
You are correct that 260E = 100W.
“Supplementary graphs may help motivate efforts to overcome misunderstandings:”
Clearly a teacher speaking here. I have 48 years experience with educator speak.
Thanks for the graphs! I am hoping you do not have an issue with my saving them for future reference? Also, I echo Lucy’s reasoned points. As well as the following thoughtful intimations;
“Combining the morsels of stark data given in the last two posts, one could draw the odd conclusion that the AMO drives North Pacific SSTs (or vice versa). Clearly it is more likely that both share an astrophysical forcing driver.”
You have the goods. Put your foot in it! Matt that sucker! Let ‘er rip. Blow our minds!
Cheers!
What Phlogiston said. This is laconic to the point of unintelligibility.
Re: Ric Werme
As indicated, AMO was featured in the earlier article.
I second the request for a longer article with a bit more explanation. Although many here at WUWT are well acquainted with the subjects that are discussed, there have been many new readers since the Climategate e-mails.
Please explain terms and abbreviations so interested laypeople joining us have a chance of understanding.
A tip to article writers from my technical writer husband. Run your article by a lay person. If he understands it great. If he asks questions you now know where to beef up the article.
the technical writer’s guinea pig
In select response to a few comments (e.g. here & here):
Regarding physical drivers:
As I have indicated many times in the past:
I leave the physics to physicists.
Elaboration:
I am raising questions, not providing answers. Climate investigations are relying far too heavily on untenable modeling assumptions — for example: misapplication of inapplicable assumptions of standard statistical methodology – and to make it worse: with insufficient [& in many cases completely absent] diagnostics. Spatial phase-relations are not irrelevant to global temporal analysis due to “Simpson’s Paradox”. There is no use putting the cart before the horse, so it is back to fundamentals. A multidisciplinary effort appears necessary.
–
Regarding succinctness:
Many people are busy. They need the soundbite and ski (skim & skip) through details. (Details can be discussed in the comments section by those with extra time.)
No less importantly:
Details arising in the last discussion were, in part, responsible for the theme of the current post. Without first clearing up the misunderstandings about what PDO is and what it is not, there seemed to be little hope of having an audience prepared for future posts in this series.
Re: Michael Larkin & Gail Combs
The presentation style is deliberate.
In part, I base the following comments on years of experience running online forums:
There are many voices in the choir and the audience is not solely political. At this point in time an expanded article would undermine the core message. There may come a time when elaboration will be both feasible & strategic — for starters, if sufficient funding becomes reliably sustainable.
—
Re: dp
Important:
That’s not a temporal lag. It’s related to spatial phasing.
Bear in mind that so far we’ve only looked at the North Atlantic & North Pacific in this series. (This is just how the story begins…)
Also dp:
We have not yet even gotten into variation of wavelet parameters.
Suggestion for anyone with the tools:
Run the complex Morlet 3pi/2 analysis and take a look at the results for the interval dp singles out.
(I may include this analysis in a future article addressing the Southern Oscillation, Southern Ocean, Southeast Pacific, &/or Indian Ocean.)
Posted yesterday (Sept. 3, 2010):
Tisdale, Bob (2010). An Introduction To ENSO, AMO, and PDO — Part 3.
http://bobtisdale.blogspot.com/2010/09/introduction-to-enso-amo-and-pdo-part-3.html
Convenient timing — thanks Bob.
Readers will note that Bob dispels many of the myths about PDO.
(Due to my investigations of EOP [EOP = Earth Orientation Parameters] I have a few reservations, but at present they are neither worthy of my time nor Bob’s, as I have more work to do before such an exchange can be fruitful.)
Note the comment left by Bill Illis, who often raises highly worthwhile points.
Is the PDO index useless? No. Rather:
Sensible interpretation of multivariate statistics requires (a) an intimate understanding of the impact of abstract mathematical assumptions, including (b) the application of a battery of post-analysis diagnostics.
In the specific case of PDO vs. North Pacific SST:
Don’t be surprised if thorough diagnostics reveal an instance of what statisticians call “Simpson’s Paradox”.
See for example Bob’s illuminating Figure 18:
http://i52.tinypic.com/9lgxlg.jpg
[If this figure is surprising, this may indicate insufficient conceptual understanding of PCA (& factor analysis more generally).]
—
Re: INGSOC
Good instincts! I do have experience teaching stats – (and yes I am restraining the pace at which new material is released…)
Thanks for the supportive comment!
Best Regards.
I don’t understand the graphs or what the point of this posting is.
Could someone please explain for me?
Paul, thanks very much. I have copied your second graph from above into my next climate presentation. You have provided a part of the physical link in Friis-Christensen and Lassen theory.
Your graph has predictive power. What would it look like if you extended the solar cycle length line for Solar Cycles 24 and 25, making them each 12 years long as per Solar Cycles 5 and 6 of the Dalton Minimum? I think you’d get a sea surface decline of 1.5 to 2.0 degrees by 2020.
Once again, great stuff and thank you.
Since comments have now moved to this thread I’d better repeat my post from late in the first thread and which might otherwise be missed by someone who might want to attempt a reply:
Interesting stuff and at present somewhat beyond my capability to comment constructively.
However the mechanisms that give rise to oceanic and solar cycles are very important to top and tail my attempt at setting out a coherent climate overview and describing the way the troposphere then deals with (possibly independent) influences from within the oceans and from variable solar activity.
However I do have some questions.
How significant are all these potential mechanisms compared to the variability that the sun and oceans would be quite capable of setting up on their own within the climate system from just changing the global albedo via latitudinal shifts in all the main cloud bands and thus introducing variability of solar shortwave input into the oceans ? Then the internal structure of the oceans and density/ salinity/ temperature driven cycling movement within them would do the rest.
Couldn’t the sun and oceans pretty much do it all on their own ?
Wouldn’t all those potential mechanisms just provide a modulating effect possibly a whole order of magnitude weaker ?
David Archibald says: September 4, 2010 at 8:43 pm “…Your graph has predictive power. What would it look like if you extended the solar cycle length line for Solar Cycles 24 and 25…”
Since the SCL function variable is based on solar cycle shape (apparently as smoothed by some time-average algorithm), based on what I see here, the “predictive” period is no greater than the past solar cycle, less a residual portion of whatever averaging period was used to smooth the raw solar data, at least sufficient to avoid taking the slope at a discontinuity. Using putative SC24/25 curves would be employing extrapolations to perform an extrapolation. Without a cited physical mechanism, the predictive power would therefore seem to be close to zero.
Fascinating curve matching exercise, though, and there may be something useful here. I’m just not sure what it is yet.
Re: Orkneygal
Since not long after I began climate investigations in late 2007, I have believed that something terribly simple has been right under the noses of physicists & climate scientists – but overlooked — for example due to inappropriate analysis, such as reliance on untenable assumptions, masking due to spatiotemporal aggregation criteria, failure to appreciate derivatives & integrals, or whatever – i.e. due to lack of attention to fundamentals. To explore what might have been overlooked, I spent much of the last 2.75 years auditing the work of others [including calculations], while also pursuing ideas arising during audits.
There have been several attempts to explain “60 year” natural climate “cycles”. The thing is: Empirical data reveal the cycles to be nonstationary – i.e. they don’t “stay” 60 years long.
I leave the physics to physicists. (My background is in landscape ecology, physical geography, statistics, engineering, & forestry.) However, I have left an empirically-motivated suggestion:
http://wattsupwiththat.com/2010/08/18/solar-terrestrial-coincidence/#comment-475401
Further elaboration at this point in time would be both burdensome & premature. The practical points [from a layperson’s perspective] might be that (a) an alternative line of inquiry into natural terrestrial oscillations is under development and (b) it does not rely on notions of stationary “60 year cycles”.
–
Re: David Archibald
I will reiterate that the shared pattern involves rate of change of solar cycle length. Thus, anyone using the shared pattern as a basis for prediction based on 2 consecutive 12 year cycles would predict no change (since 12 – 12 = 0).
Personally: I will leave forecasting to forecasters for now. My interest remains in studying recorded patterns.
Thank you sincerely for your kind & encouraging comments David – much appreciated.
I thought I had some idea of movements in temperature and even in the various ocean patterns (PDO etc). I also thought that I had some training and understanding of ststistics (most CA posts for example are at least basically understandable to me).
But Paul Vaughan, you are far too criptic for me, with blizzards of initials and references soe where else, instead of sentences. I understand that you are a scientist, used to writing for fellow scientists, who share a common understanding. I also realise that you cannot, or will not, change your preferred writing style to suit those of us with different training and experience.
I believe that there are a few people reading this thread who DO understand quite clearly. I sense that it contains very interesting information and is pointing towards an important hypothesis, whic may be, or may not be, both valid and earth shaking.
Can somebody please help out, by rewriting this post in language which is more understandable, not necessarliy to the general public, but at least to the large number of people at WUWT who are knowledgeable about climate matters, but who are not experts in Paul’s field.
We would be very grateful.
David Archibald says:
September 4, 2010 at 8:43 pm
Paul, thanks very much. I have copied your second graph from above into my next climate presentation. You have provided a part of the physical link in Friis-Christensen and Lassen theory.
How?
Your graph has predictive power. What would it look like if you extended the solar cycle length line for Solar Cycles 24 and 25, making them each 12 years long as per Solar Cycles 5 and 6 of the Dalton Minimum? I think you’d get a sea surface decline of 1.5 to 2.0 degrees by 2020.
No you wouldn’t. The graph might even predict a rise because SC 23 was ~12.5 years long, i.e. the rate of change would be positive (I’m assuming shorter is positive and longer is negative).
Once again, great stuff and thank you.
It doesn’t support your work, David.