Does the Pacific Decadal Oscillation have predictive skill for global temperature?

Reader Eric Worrall writes:

I was playing with Wood For Trees, looking at the relationship between Pacific Decadal Oscillation vs global temperature (Hadcrut 4), when the following graph appeared.

The interesting thing is PDO in this graph appears to have predictive skill for changes in global temperature – the changes in PDO appear to match changes in global temperature, once the graphs are normalised, but temperature lags PDO by around 5 years.

PDO_worrall_fig1

Source: http://goo.gl/hzOxW
Is it all just coincidence? Bad endpoint choice? Or does it in fact have some predictive value?

Readers are invited to weigh in.

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102 Responses to Does the Pacific Decadal Oscillation have predictive skill for global temperature?

  1. Ashby Manson says:

    Is this surprising? Didn’t everyone have a globe when they were a kid? I used to position it and marvel that the pacific was damned near half the world.

  2. Alan S. Blue says:

    Turn it into an empirical model (just a best fit with a variable for time lag) and make a prediction for now-to-2018.

    A full treatment would sequester 1/3 of the data, and both make a fit and determine error bars based solely off of the first 2/3 of the data. Then make a new fit with all of the data, yielding another set of errors as well. Then predict.

  3. Bryan A says:

    Interesting Graph. two things really stand out though.
    1 The almost perfect agreement between the interrelationship
    2 The apparent divergence at 1940 that indicates the Temperature portion is increasing

  4. My theory is that the sun warms the ocean and – after an interval (a transient response) – the ocean warms the atmosphere after a 99-year time lag (152 years in the case of the Pacific, but the smaller oceans bring down the mean). If I’m right, the low level of solar activity in WWI and the 1920s are due to deliver us some bitter winters.

    http://endisnighnot.blogspot.co.uk/2012/03/lets-get-sorted.html

  5. Steve Keohane says:

    I see several apparently instantaneous responses. For example, roughly, 1970, ’72 and ’74 have peaks in PDO that coincide with peaks in temperature. I don’t see a consistent lag overall, and only a year difference at the minimum of each trace at 1976-7ish. I do find the correlation disturbing though, it is cool enough thank you.

  6. Resourceguy says:

    Nice, a model with a lag term would do it but I think some testing with AMO and some attempt at solar cycle variable construction from cycle normalization would also be interesting. The South Atlantic sea surface temperature data would also be worth looking at.

  7. Mark Bofill says:

    I believe I remember seeing on Dr. Spencer’s site that he’s a fan of the PDO for explaining climate change, although I can’t say whether or not a direct correlation like this is what he had in mind. Could be, for all I recall right now. I ought to go look.

  8. Louis says:

    So if this pattern holds, does that mean we can expect temperatures to drop for at least the next 5 years?

  9. Genghis says:

    It makes perfect sense to me that measured air temps in the Northern Hemisphere would lag ocean temps.

  10. Dan Harrison says:

    Resourceguy suggest the South Atlantic sea surface temperature data would also be worth looking at. I’ll suggest separating the Southern Hemisphere from the Northern Hemisphere temperature data for the following reason. Remove the approximate 0.5 deg Anthony identified as due to positive biasing of the Northern Hemisphere temperature data from “corrections” and from the heat island effect. This may remove the “apparent divergence beginning at 1940 that indicates the Temperature portion is increasing” identified by Bryan A. Note that the Southern Hemisphere temperature data should not show the degree of temperature biasing shown by Anthony in the Northern Hemisphere.

  11. Steven Mosher says:

    PDO is temperature. predicting temperature from temperature tells you nothing. same with all the ocean patterns. OF COURSE they allow you to predict the global temps. they are part of the thing being predicted. Its like using CET to predict global temps. Of course you can.

    Put another way. PDO is the effect

  12. George McFly......I'm your density says:

    Science is the process of observation and analysis.

    Nice observation, let’s analyse it

  13. Theo Goodwin says:

    You are extrapolating existing graphs into the future. That is not prediction, except in the trivial sense that you are asking “Will the future resemble the past?”

    For prediction, we need to know more about the PDO. It might consist of many other natural regularities. We need to know enough about some of them that we can create reasonably accurate descriptions of their characteristics. Those descriptions will take the form of general statements, something along the lines of Kepler’s First Law: All planetary orbits are ellipses with the Sun at one of the foci. From general statements and descriptions of existing conditions we can deduce and, thereby, predict descriptions of future conditions.

    The PDO is worthy of serious study and experiment to learn its characteristics. Unfortunately, given the regime running climate science at this time, nothing is being done.

    For the person who complains that we have only one PDO and, for that reason, cannot experiment on it, please note that experimentation should begin with passive observation of the natural regularities that make up the PDO.

  14. Steve Garcia says:

    I got interested in the PDO very early on – my recollection is somewhere around 2000 or 2001, but that may be in error. I think it is significant that the PDO was not even discovered by a climatologist or meteorologist, but by biologist Steven Hare in 1997, who was researching salmon catches in the Pacific Northwest. He found that when the northern Pacific water temps were in a warm regime, the salmon catches were low, and vice versa – and that the warm and cold regimes appeared to last decades before flipping to the other regime.

    In 2005 I was emailing with then Oregon State Climatologist George Taylor. He wrote me the following (which I reproduce here without his permission and hope it is no big deal to him):

    “I’ve known about PDO since the early 1990s, since before it was named (I missed my chance to name it!). Here’s a link to an article I wrote in 1996 and posted in 97…”

    George was one of those in the climatology world who didn’t agree with the CAGW meme, and it was amazing in a state like Oregon that he was in his position. He got a LOT of flack within his state. Then he was let go as the state climatologist a few years ago. and the article was at some point removed from the state website.

    I agree with Ashby Manson above, about how BIG the Pacific is. I looked it up once – 32% of the entire world’s surface area. To the eye it LOOKS like half the globe. To me whatever the Pacific does it does without the effect of humankind’s pitiful contribution. The Pacific is the elephant in the room. It seems pretty obvious to me that from the latency of its warm and cold regimes that nothing is going to push the Pacific around. It was said back then to be ten times as big as the El Niño.

    No one is going around and arguing that humans are affecting ENSO. If we aren’t affecting ENSO, then what are the chances of us affecting the PDO? Pretty low.

    And if we aren’t affecting the two big mamas of Pacific climate, then any pretense that we are affecting the rest of the globe’s climate are, without seriously incontrovertible evidence – what courtrooms call “stipulated evidence” – on very thin ice.

    One more thing: The climate models throughout the 1990s were calaimed to be accurate and complete. Those were the ones upon which the IPCC based the projections of 5.8°C rise by 2100. Yet every one of those could not have included the PDO, which hadn’t been discovered yet. We were all to believe that without the single biggest factor in those model’s code, they were right. And then after the PDO entered the room, it took a good while before it was included. And then they acted as if they were right all along. How could they have been right both before and after, if the before was missing the elephant in the room?

    Steve Garcia

  15. Mark Bofill says:

    Steven,

    PDO is temperature. predicting temperature from temperature tells you nothing. same with all the ocean patterns. OF COURSE they allow you to predict the global temps. they are part of the thing being predicted. Its like using CET to predict global temps. Of course you can.

    Put another way. PDO is the effect

    Oh, I dunno. Spencer says it might drive cloud changes. Of course, Trenberth will tell you clouds don’t control climate, so there you have it I guess. Except Spencer doesn’t agree.

  16. Mark Bofill says:

    Steven,

    Wait a second here. How can it be the effect, if the effect is driven by CO2, yet the PDO changes phase every 20-30 years?

    It does not make sense. Ladies and gentlemen of the alleged jury, If Chewbacca does not live on Endor you must acquit. Thank you.

  17. GlynnMhor says:

    The PDO could be regarded as the change in the ratio of ‘nino’ to ‘nina’ events , which seems to have a sixty year cyclicity comparable to the sixty year temperature cyclicity.

    We’ve only been measuring the ENSO index for one cycle, but since temperature seems to be a good proxy for that cycle, it could be extended back into the 1800s.

    But what, then, drives the PDO?

  18. feet2thefire says:

    @Theo Goodwin June 5, 2013 at 3:44 pm:
    “You are extrapolating existing graphs into the future. That is not prediction, except in the trivial sense that you are asking “Will the future resemble the past?”

    ???? You can’t be serious. ALL scientific predictions are extrapolations from existing evidence. All non-scientific predictions use crystal balls in place of existing evidence.

    The ludicrous part of this assertion is that the climate models can NOT even make the future resemble the past. Yet all CAGW is based on assertions that they can extrapolate the future from and make it look like the past (even if they do it so utterly unsuccessfully).

    EVERY linear trend line in all of climate science is an extrapolation. You argue against your own case.

    (Personally I see the use of straight line linear regression as completely flawed, because nature doesn’t do straight lines in complex systems, not over any great length of time. However some linear regression is necessary – I just think the output should be some higher order curve..)

    Steve Garcia

  19. DirkH says:

    Some other correlations.

    inverted SOI is leading indicator for global temps -7 Months
    (“The Southern Oscillation Index, or SOI, gives an indication of the development and intensity of El Niño or La Niña events in the Pacific Ocean. The SOI is calculated using the pressure differences between Tahiti and Darwin. ” from BOM)
    http://jonova.s3.amazonaws.com/guest/leyland/soi-global-temps-jan2011.pdf

    Funnily SOI in turn seems to be correlated with the Ap index

    see at 5:20

  20. thingodonta says:

    Perhaps someone has altered the data to match the PDO, but offset it by 5 years so is wasn’t so obvious? Just a thought, it seems to match too much, within nature that is so chaotic.

  21. gnomish says:

    presented: temperature lags PDO by around 5 years.

    Steven Mosher says: Put another way. PDO is the effect

    reversing cause and effect, again?

  22. Manfred says:

    Steven Mosher says:
    June 5, 2013 at 3:40 pm
    PDO is temperature. predicting temperature from temperature tells you nothing.
    ——————————————————

    PDO going negative predicts about 30 years of lower trends or even falling temperatures.

    I haven’t seen any such prediction from temperature.

    Same for AMO.

  23. Manfred says:

    #Steve Mosher

    PDO = low frequency tail of ENSO accounting for an appreciable fraction of the warming trend

    http://www.esrl.noaa.gov/psd/people/gilbert.p.compo/CompoSardeshmukh2008b.pdf

    “Because its [ENSO's] spectrum has a long low frequency tail, fluctuations in the timing, number and amplitude of individual El Nino and La Nina events, within, say, 50-yr intervals can give rise to substantial 50-yr trends…”

    “…It [The Pacific decadal oscillation or the interdecadal Pacific oscillation] is strongly reminiscent of the low-frequency tail of ENSO and has, indeed been argued to be such in previous studies (e.g. Alexander et al 2002, Newman et al 2003, Schneider and Cornuelle 2005, Alexander et al 2008)…”

    “…it also accountd for an appreciable fraction of the total warming trend…” (see figure 9b )

    “…In this paper, we have argued that identifying and removing ENSO-related variations by performing regressions on any single ENSO index can be problematic. We stressed that ENSO is best viewed not as a number but as an evolving dynamical process for this purpose…”

  24. JimF says:

    I’m seeing the “PDO Effect” right out my window. Winter lasted until May, and spring is a weak, wet, cold and clammy thing, with little relief in sight. I have to do this for how many decades?

  25. TRM says:

    ” Steven Mosher says: June 5, 2013 at 3:40 pm
    PDO is temperature. predicting temperature from temperature tells you nothing. same with all the ocean patterns. OF COURSE they allow you to predict the global temps. they are part of the thing being predicted. Its like using CET to predict global temps. Of course you can.

    Put another way. PDO is the effect”

    The temperature is the temperature but it does lead the air temp. So a change in the ocean temperature results in a following change in air temperature over North America at least.

    The PDO is definitely a leading indicator IMHO.

  26. rgbatduke says:

    Post hoc ergo propter hoc. When an argument is a named logical fallacy, why make it?

    If you prefer English, correlation (even lagged correlation) is not causality. If A and B have similar graphs (when rescaled, moved, etc) with or without A temporally preceding B, it leaves open:

    * A causes B (desired/claimed conclusion)

    * B causes A (yes, this is still possible, it is just less easy to explain. Think about that, the need for an explanation.)

    * A and B are both caused by C (not shown), or C, D, E… (not shown). The lag might be due to one of these (not shown) causes — in the correct explanation.

    * A really is B, so one isn’t really measuring two different things, one is measuring two different sides or aspects of the same thing. Steve Mosher points this possibility out above, although not really convincingly, given the size of the Pacific.

    If the Pacific is almost half of the globe, and the PDO is a monotonic transform of the temperature of the Pacific as he seems to assert, why does global average temperature lag the average temperature of the Pacific? It is difficult to imagine an explanation for this lag if it is as simple as global temperatures are a direct average of the temperatures used to define/infer the PDO. Ordinarily if B (global temperature) is the average of A (Pacific temperatures) and D (everything else) and B is independently varying from A, then one does not expect B to systematically lag and follow A. In context, why is it only the Pacific that experiences global warming due to a global cause first, with everything else experiencing it later? So his argument appears inadequate to — without an explanation — contradict A causes B, although of course it is a possibility.

    * A and B are are independently varying due to a variety of complex causes, and their lagged covariance is an accident of the particular values of their mutual parameters including a few that are shared. It will disappear in the future without a trace, just as it didn’t exist in the past (back before we were around with thermometers to look for it.

    * A and B are randomly varying systems with shared characteristic timescales, and their lagged covariance is pure chance. Given only a few “transitions” of similar timescale, that isn’t as unlikely/impossible as one might think, and it is easy to find similar artifacts in any sufficiently long timeseries.

    So, given all of these possibilities how can we choose between them? On the basis of explanations that make sense (including arithmetical/computational sense). One has to explain:

    a) Why the PDO varies the way that it does. This is already a daunting task, as the PDO is not an independent phenomenon.

    b) How the Pacific couples to the rest of the planet. This is of course part of the explanation for why the PDO varies the way it does.

    c) How the PDO causes the rest of the planet to vary the way that it does. No, this isn’t circular reasoning, it is the observation that this is a coupled dynamic system so that separating out independent “causes” is all but impossible.

    Here’s my “explanation”: The PDO varies the way it does because of the prior state of both the PDO and the rest of the world, including all of the major oscillations, the Sun, the state of GHGs and aerosols and volcanoes and the position of the Earth in its orbit and maybe other stuff we haven’t even realized is important yet, because of its current state (and the current state of a lot of those other independent or coupled variables) and a whole lot of physics. The rest of the world will vary in the future in a way that depends on the prior state of the rest of the world (including the PDO etc), on its own prior state, all those variables, as well as the current state, and possibly some unknown stuff.

    What is the “cause” of the behavior of any part of this strongly coupled, nonlinear, chaotic system?

    Everything. Nothing. CO_2 levels. Solar state. The particular angle of attack of some Pangean butterfly’s wings when they beat a hundred million years ago. Dark matter.

    We cannot predict the climate. We cannot even predict the damn weather, not more than a week or so out. There are really good reasons we cannot predict the weather, and equally good reasons we cannot predict the climate. It is true that they aren’t quite the same problem, and sometimes one can predict the average behavior of a system in the long run (whatever that means) when one cannot predict its short time behavior at all reliably, but when I say we cannot predict the climate I mean that we cannot even understand the past behavior of the climate! We have no friggin’ idea why the MWP was warm, the LIA was cold, and why the world warmed (without CO_2 increase to drive it) since the Dalton minimum. We cannot predict the future state of one of the only important contributor of heat to the system, an enormously important cause whose effects on the Earth are complex and only beginning to be understood. To claim otherwise is an enormous act of intellectual hubris and scientific fraud — unless and until you can back up the claim with actual predictions, consistently validated. Or hey, I’d settle for a halfway decent hindcast or two, back to (say) 0 BCE or 16,000 BCE or 120,000 BCE or 50,000,000 BCE. The only thing we learn looking at the real climate record of the Earth is that it is always changing, that the changes are sometimes sudden and profound, and that we have no idea why they occurred or why they WERE either sudden, or gradual as the case may be, or gentle and moderate, or profound and catastrophic as the case may be.

    Some of these things we are likely to never be able to properly prove or understand as the evidence is simply gone into the past. The Ordovician-Silurian transition — an ice age that began with 7000 ppm CO_2, and that peaked in glaciation a few million years later with CO_2 still at 4000 ppm. What’s up with that? Space aliens came and directed a freezing ray at the Earth, straight out of Buck Rogers? The Sun decided to turn off (partly) for a million years or so? A civilization consisting of highly evolved giant spiders had a nuclear war and triggered a nuclear winter a few million years long? Sure, we can propose more sensible alternatives, but honestly they will all still feel like science fiction, and in all probability none of them can either be verified/supported or falsified, at best they can be shown to be a consistent possibility.

    Why is it so very difficult to say “we don’t know”?

    rgb

  27. Spartacus says:

    Either a cause or an effect, it seems reasonable to see that none of the measures have a strong correlation with the CO2 concentration. Both PDO and AMO must be correlated with atmospheric temperature, after a normalisation, for instance made with the total area or volume of the effective thermal water body of the Pacific and Atlantic, to see how the graphic behaves. It must include the Indian ocean too. Like the Milankovitch cicles, the effect of a single parameter can be important but is the correlation of all parameters that matters. We must compare, for instance, peaks of phase and out of phase between these oceanic oscillations. The oceans are a lot more resilient to temperature change and should be the right normalised temperature proxy for the earth surface thermal behaviour.

  28. Richard M says:

    Mosh, I guess you’ve never read Tisdale’s comments on the PDO. It is not temperature, it is an after effect of ENSO.

    I’ve been pushing the PDO mode as the primary driver of global temperatures at Yahoo and other sites. The correlation is much better than CO2. I use slightly different dates but close enough. However, it still leaves open the question of what drives ENSO.

  29. See:

    Joe D’Aleo’s pdf on PDO+AMO at icecap.us, which shows, for example, the strong correlation between PDO+AMO and the US temperatures.

    AMO is Atlantic Multi-Decadal Oscillation.

    and his results are also presented at <a href="http://www.appinsys.com/GlobalWarming/PDO_AMO.htm"appinsys.com

    appinsys.com also gives comparisons between temperature and PDO alone, AMO alone, ENSO alone, and AO-NAO (Arctic Oscillation and North Atlantic Oscillation). For ENSO, the “integrated Nino 3.4 SST index”–which is just a running summation of that index–correlates with the global SST anomaly; Bob Tisdale is the one who showed this, and of course he advertises his recent, inexpensive book on the subject of the ocean oscillations on his site.

  30. Ian Wilson says:

    This might be the answer to the question of what determines the ratio of El Nino’s to La Nina’s and so possibly world temperature.

    Long-Term Lunar Atmospheric Tides in the Southern Hemisphere
    Ian R. G. Wilson and Nikolay S. Sidorenkov
    The Open Atmospheric Science Journal, 2013, 7, 51-76

    http://www.benthamscience.com/open/toascj/articles/V007/TOASCJ130415001.pdf

    Relevant part of .ABSTRACT

    Finally, an N=4 standing wave-like pattern in the MSLP that circumnavigates the Southern Hemisphere every 18.6 years will naturally produce large extended regions of abnormal atmospheric pressure passing over the semi-permanent South Pacific subtropical high roughly once every ~ 4.5 years. These moving regions of higher/lower than normal atmospheric pressure
    will increase/decrease the MSLP of this semi-permanent high pressure system, temporarily increasing/reducing the strength of the East-Pacific trade winds. This may led to conditions that preferentially favor the onset of La Nina/El Nino events.

  31. u.k.(us) says:

    If weather wasn’t variable, and previously known to be so, why would we have records extending back ~ 450 years ?

  32. Richard M says:

    One of the features of the PDO has to do with atmospheric pressure. Since the jet streams are driven by differences in pressures the PDO could impact the jet streams and provide a mechanism to move the jets a little north or south as S. Wilde has mentioned many times. And, if this ties into solar/lunar tides as has also been mentioned previously, it could turn out to be the basic mechanism.

  33. John West says:

    First off, thanks RGB for that comment.

    The problem with any analysis of the data is that the data has been muddled with to the point where one has no idea if what one is looking at has any resemblance to reality or not. The only global temperature record I trust is the satellite record which unfortunately means only a snipet of time is available for earnest inquiry.

  34. feet2thefire says:

    @Richard M June 5, 2013 at 6:10 pm:

    One of the features of the PDO has to do with atmospheric pressure. Since the jet streams are driven by differences in pressures the PDO could impact the jet streams and provide a mechanism to move the jets a little north or south as S. Wilde has mentioned many times. And, if this ties into solar/lunar tides as has also been mentioned previously, it could turn out to be the basic mechanism.

    This is very tantalizing.

    Total speculation: The Pacific being by far the largest non-land area on the planet, climate over it may have the capacity to organize in a way not possible elsewhere because of the complicating factors of irregular land forms. Kind of like a blank metal sheet where oscillations can form patterns in lycopodia (sp?) sprinkled on it.

    This may be contributing of both ENSO and the PDO and allowing them to build up the power they do. And once they do, the patterns may achieve some stability/staying power.

    Like I said, total speculation. But interesting to think about.

    Steve Garcia

  35. u.k.(us) says:

    John West says:

    June 5, 2013 at 6:17 pm

    First off, thanks RGB for that comment.

    The problem with any analysis of the data is that the data has been muddled with to the point where one has no idea if what one is looking at has any resemblance to reality or not. The only global temperature record I trust is the satellite record which unfortunately means only a snipet of time is available for earnest inquiry.
    ——————
    Not so sure what the satellites are measuring.
    Lots of adjustments.
    Nuthin’ against the guys running them.

  36. Girma says:

    Eric Worrall

    My theory is a multidecadal cycle oscillates relative to a secular trend. The recent warming (from 1973 to 2005) coincides with the warming phase of the multidecadal oscillation and its cooling phase should be from 2005 to 2037.

    Here is a graph that shows the above pattern:

    http://www.woodfortrees.org/plot/hadcrut4gl/mean:756/plot/hadcrut4gl/compress:12/plot/hadcrut4gl/from:1974/to:2004/trend/plot/esrl-co2/scale:0.005/offset:-1.62/detrend:-0.1/plot/esrl-co2/scale:0.005/offset:-1.35/detrend:-0.1/plot/esrl-co2/scale:0.005/offset:-1.89/detrend:-0.1/plot/hadcrut4gl/mean:756/offset:-0.27/plot/hadcrut4gl/mean:756/offset:0.27/plot/hadcrut3sh/scale:0.00001/offset:4/from:1870/plot/hadcrut4gl/from:1949/to:2005/trend/offset:0.025/plot/hadcrut4gl/from:1949/to:2005/trend/offset:0.01

    Instead of IPCC’s “0.2 deg C/decade warming” the warming rate should drop to about 0 deg C/decade for the 30-years period from 2005 to 2037.

    As a result, most of the sea ice lost in the warming phase from 1973 to 2005 is natural.

  37. Steve Fitzpatrick says:

    Steve Mosher,
    I don’t usually disagree much with your comments, but in this case, I think you are mistaken. The PDO is NOT a temperature change per se, but an index which reflects the pattern of temperatures across the North Pacific, and trailing averages (eg 20 to 25 years trailing) of the PDO index do appear to correlate with changes in global average temperature. It is a bit hard to see how the PDO index from decades ago could have predictive power for present day average surface temperature if the PDO index is simply a measure of the global average surface temperature. See: http://rankexploits.com/musings/2013/pseudo-cyclical-contribution-of-the-pdo-to-earths-recent-temperature-history/

  38. James Cook says:

    You get pretty much the same correlation by using sunspots instead of PDO. I think if the PDO had hands, it would just point up at the sun.

  39. oMan says:

    rgbatduke says:
    June 5, 2013 at 5:12 pm
    “Post hoc ergo propter hoc. When an argument is a named logical fallacy, why make it?…Why is it so very difficult to say ‘we don’t know’?”

    Brilliant. Thanks.

  40. Rud Istvan says:

    Others have posted on the logic of correlation and causation. But those statements are mainly true for simple linear systems. Weather and climate are nonlinear dynamic systems (meaning they have at least one lag and one feedback).
    In such systems, especially if complex (meaning many variables) even the language of causality gets very murky. Which says PDO or CO2 as ’causes’ of observed temperature change is probably simplistic. Whichnis my reply to the post’s question. But there is more.

    Analogy. Which came first (a causation question), the chicken or the egg? From the egg’s perspective, a chicken is just another way to make another egg. The premise of the question is false, because they evolved together ( metaphore for earth’s climate, which plainlynrelies on the biosphere formthings like carbon sequestation, and atmospheric humidity from plant transpiration). To borrow from Willis’ important post on a single linear equation (actually his orbiter dictum), chickens and eggs are emergent properties of the system we call life. Anyway, you get the idea.

    So the question about CO2s causative impact is almost like asking a chicken what impact the thickness of the carbonate eggshell will have on chickens. To which, if I were a chicken, I would cluck, if it gets a whole lot thicker real fast, fewer chicks will be able to hatch out. Not good. But check out this chicks beak. It can peck through a lot more than a wimpy shell twice as thick as now. And why do you think all eggshells are the same thickness? DDT thinned eggshells (cold analogy) and killed raptors (Rachel Carson Silent Spring, humans as raptors analogy). And how fast did you say this was going to happen? (Adaptation versus mitigation analogy).

    Just some food for thought.

  41. Fred says:

    rgb
    Because they can’t feel intellectually superior.
    because they can’t full-fill their ideological objective.
    because you sure as hell can’t get funding.
    If you say we don’t know

  42. rogerknights says:
    Why is it so very hard to say, we don’t know?

    What, we blurry?

    I.e, extremist/crusader types abhor ambiguity / uncertainty and see things in black / white terms, with themselves as the white hats. (Or white robes / lab coats, as the case may be.)

  43. rogerknights says:

    Oops, I indented that last entry instead of outdenting it.

  44. Manfred says:

    Richard M says:
    June 5, 2013 at 5:49 pm
    However, it still leaves open the question of what drives ENSO.

    ——————————————–

    Some recently came up with the idea, that heat is currently sequestered into the deep ocean and will return and drive temperatures up in a couple of years or decades.

    That will not happen because it would reduce entropy and violate the second law of termodynamics.

    Temperature increases in the deep ocean are at least an order of magnitude smaller than at the surface, even if we believe the sudden jump while switching to the ARGO system.

    That heat sequestered will not recombine when deep ocean water upwells to the surface and so will surface temperatures hardly be affected by the minusule increases in deep ocean temperatures during the last decades.

    There will therefore also be no effect on ENSO.

  45. rgbatduke says:

    The problem with any analysis of the data is that the data has been muddled with to the point where one has no idea if what one is looking at has any resemblance to reality or not. The only global temperature record I trust is the satellite record which unfortunately means only a snipet of time is available for earnest inquiry.

    Me too. I have hopes of ARGO data in a decade or two, but at the moment there is way too much trouble with the data and way too few buoys.

    Let me amend that — I don’t completely reject data from earlier measurements, but I pay it little attention when it is presented (as it always is) without error bars. Not just statistical estimates of e.g. s.d., but actual estimates of probable error (which will, of course, be strictly greater than s.d. to account for unknown systematic errors etc).

    Of course if you include honest error bars, the curves are a lot less exciting, because most of the exciting behavior is variation on the order of the error bars over decades or more. Honestly, I rather wish that the satellite data was presented with an error estimate too.

    rgb

  46. Richard M says:

    Girma says:
    June 5, 2013 at 6:34 pm
    As a result, most of the sea ice lost in the warming phase from 1973 to 2005 is natural.

    The sea ice lost in the Arctic correlates almost perfectly with the AMO lagged by a few years. While I think the PDO may drive global temperatures, the AMO has its own impacts.

  47. rgbatduke says:

    That will not happen because it would reduce entropy and violate the second law of thermodynamics.

    Ah, would you care to prove, justify, or otherwise support this assertion? I’m not defending the assertion that heat sequestration is occurring on a grand scale, but it is surely occurring all of the time on some scale, even if only the minor scale of sunlight warming the ocean by day and the heat being released at night. I cannot think of any good reason to think that this or any process akin to this would either reduce entropy or violate the second law.

    Note well that even if cold water upwells in some location, if the cold water is warmer than the water that was there above in the first place (as, if you think about it, it is likely to be) it will have the effect of raising the air temperature above it, even if that air is warmer than the water. If you increase a boundary temperature in any heat flow problem, you will fairly generally raise temperatures everywhere as the heat flow adjusts, without violating the second law. This is not a static thermal equilibrium problem, it is a dynamical process in an open system.

    rgb

  48. Steve says:

    I think if you redate lower temperature values by fifty years and deselect those you don’t like, your graph will clearly show that we are warming at a rate never seen before…I mean, what would Mike do?

  49. Theo Goodwin says:

    feet2thefire says:
    June 5, 2013 at 4:03 pm
    @Theo Goodwin June 5, 2013 at 3:44 pm:
    “You are extrapolating existing graphs into the future. That is not prediction, except in the trivial sense that you are asking “Will the future resemble the past?”

    “???? You can’t be serious. ALL scientific predictions are extrapolations from existing evidence. All non-scientific predictions use crystal balls in place of existing evidence.”

    Existing evidence consists of true observations of the environment. Observation statements imply only themselves. Science is a system of hypotheses that are taken as true because they have a long record of confirmation. They become confirmed when they are used to imply observation statements that are found to be true.

    As an introduction to empirical hypotheses, read some internet account of Kepler’s Three Laws. Except for the radiation laws, climate science today exists entirely as empirical hypotheses.

    As an introduction to theoretical hypotheses, read some internet account of Newton’s Theory of Gravitation, which implies Kepler’s work. The concept of gravity is theoretical.

    We need a Kepler for the PDO. Then maybe that Kepler will be followed by a Newton for the PDO. They will discover and describe natural regularities that make up the PDO.

    Short of a Kepler, we will know nothing of natural regularities that underly the PDO. The PDO might be one grand natural regularity.

    Climate science is in its infancy.

  50. Mark Bofill says:

    rgbatduke says:
    June 5, 2013 at 7:40 pm

    That will not happen because it would reduce entropy and violate the second law of thermodynamics.

    Ah, would you care to prove, justify, or otherwise support this assertion? I’m not defending the assertion that heat sequestration is occurring on a grand scale, but it is surely occurring all of the time on some scale, even if only the minor scale of sunlight warming the ocean by day and the heat being released at night. I cannot think of any good reason to think that this or any process akin to this would either reduce entropy or violate the second law.
    ——————————–
    Well, I’m not sure what Manfred was thinking, but I thought his original idea was something a little different. If the energy that would have caused 1C atmospheric warming had it not been sequestered in the deep ocean GOES into the deep ocean, you’re never going to get 1C of warming from that energy back out of the water again. I guess you can get some of it back out with the right assumptions. Generally speaking though, if the ocean is colder and denser than the atmosphere, wouldn’t most of the energy that goes into it both 1) cause less heating to the dense water than it would cause applied to the atmosphere and 2) tend to stay there unless the ocean becomes warmer than the atmosphere?
    I could be making a mistake, and I’d be most grateful for a clear correction if I am.

    Thanks

  51. Girma says:

    Eric Worrall

    Here is my correlation graph between PDO and detrended 21-years running mean of the global mean surface temperature.

    http://www.woodfortrees.org/plot/jisao-pdo/mean:252/normalise/plot/hadcrut4gl/mean:252/from:1910/detrend:0.8/normalise

    It shows the PDO is a leading indicator of the global mean surface temperature.

    It agrees with your result.

  52. dp says:

    <blockquote]Why is it so very difficult to say “we don’t know”?

    rgb

    A question I’ve brought up frequently. Often in the form “It is ok to say ‘I don’t know'”. And I don’t rule out that we can’t know. What we do know is the Earth has been a frozen snowball and an ice-free water planet at various times, so those are the known natural extremes. We know CO2 content has been very much higher and very much lower, and that it is uncommonly low now, and that the minor recent increases are having a positive influence on most things. We know none of the doomsday predictions are validated by observation. We need to stop allowing this bogieman to destroy our economy and quality of life and focus on creating jobs, not carbon tax schemes.

  53. Bob Tisdale says:

    Steven Mosher says: “PDO is temperature.”

    No, it is not.

  54. Bob Tisdale says:

    Eric Worrall: You’ve presented an argument that’s been around for a few decades.

    Unfortunately, the PDO does not represent the sea surface temperature of the North Pacific. The sea surface temperatures of the North Pacific north of 20N, where the PDO is statistically derived, is inversely related to the PDO.

    There is no mechanism for the PDO to vary global temperatures.

    See the posts, working backwards in time, here:
    http://bobtisdale.wordpress.com/2013/05/14/multidecadal-variations-and-sea-surface-temperature-reconstructions/
    And here:
    http://bobtisdale.wordpress.com/2011/06/30/yet-even-more-discussions-about-the-pacific-decadal-oscillation-pdo/
    And here:
    http://bobtisdale.wordpress.com/2010/09/14/an-inverse-relationship-between-the-pdo-and-north-pacific-sst-anomaly-residuals/
    And here:
    http://bobtisdale.wordpress.com/2010/09/03/an-introduction-to-enso-amo-and-pdo-part-3/

  55. Mike Mangan says:

    About time Bob Tisdale showed up. My two cents, the PDO is tweaked by volcanoes and Svensmark’s GCR effect. The effects take hundreds of years to cycle out and temps stay within a couple of degrees either way. Things look strange when ALL of the ocean cycles break sync, ala Swanson and Tsonis, but still temps never get too far out of hand. Just a hunch.

  56. u.k.(us) says:

    As I “knew” he would, Bob Tisdale weighs in.
    Time to listen.

  57. kadaka (KD Knoebel) says:

    Ah, how I love playing with the graphs at WoodForTrees. Even more fun with the Normalize function.

    Here you can see the obvious correlation between the Atlantic Multi-decadal Oscillation and the Arctic sea ice extent:
    http://woodfortrees.org/plot/nsidc-seaice-n/from:1979/mean:13/normalise/plot/esrl-amo/from:1979/mean:13/normalise/scale:-1/plot/nsidc-seaice-n/from:1979/mean:13/normalise/trend/plot/esrl-amo/from:1979/mean:13/normalise/scale:-1/trend

    Make the melt prediction for this year with that!

    Except starting around 2004, AMO diverged from the Arctic sea ice extent, their tends went different ways. It’s just like they warned us, the climate is getting freaky!
    (Note: due to the 13-mo running average, it’s necessary to overshoot a half year when specifying the intersection.)
    http://woodfortrees.org/plot/nsidc-seaice-n/from:1979/to:2004.5/mean:13/normalise/plot/esrl-amo/from:1979/to:2004.5/mean:13/normalise/scale:-1/plot/nsidc-seaice-n/from:1979/to:2004.5/mean:13/normalise/trend/plot/esrl-amo/from:1979/to:2004.5/mean:13/normalise/scale:-1/trend/plot/nsidc-seaice-n/from:2003.5/mean:13/normalise/plot/esrl-amo/from:2003.5/mean:13/normalise/scale:-1/plot/nsidc-seaice-n/from:2003.5/mean:13/normalise/trend/plot/esrl-amo/from:2003.5/mean:13/normalise/scale:-1/trend

    However, Arctic sea ice should lag the AMO. If the AMO makes more ice favorable, it still takes awhile for the thin first-year ice to survive and become the longer-lived multi-year ice. With some work, a four year lag gives great results, up to the 2004 freak-out.
    http://woodfortrees.org/plot/nsidc-seaice-n/from:1979/to:2008.5/mean:13/normalise/plot/esrl-amo/from:1979/to:2004.5/mean:13/normalise/scale:-1/plot/nsidc-seaice-n/from:1979/to:2008.5/mean:13/normalise/trend/plot/esrl-amo/from:1979/to:2004.5/mean:13/normalise/scale:-1/trend/plot/nsidc-seaice-n/from:2007.5/mean:13/normalise/plot/esrl-amo/from:2003.5/mean:13/normalise/scale:-1/plot/nsidc-seaice-n/from:2007.5/mean:13/normalise/trend/plot/esrl-amo/from:2003.5/mean:13/normalise/scale:-1/trend

    Voila! The trends match near perfectly until 2004, when the Arctic Ocean goes haywire.

    Now that I have conclusively demonstrated the global climate underwent a hidden chaotic transformation around 2004, it is clear that further research is required to analyze and project the degree of catastrophic impact that will result. We can only hope the federal government will pursue this matter on behalf of the general public, as required by law.

    Release the funding!

  58. J.Seifert says:

    The 61 year Jup-Sat Scafetta cycle is missing in the discussion
    as climate driver and the PDO as resulting effect…..

  59. Jean Parisot says:

    rgbatduke,

    “why they WERE either sudden, or gradual as the case may be, or gentle and moderate”

    I personally believe this is most important question for climate science. Not “are we warming or cooling” – but understanding the conditions of rapid change. I don’t even hope for a prediction of rapid change, just a way to recognize it once it starts. The consequences for millions are profound and a few months can matter.

  60. Don Easterbrook says:

    Yes, it does have predictive value and has already been done. See:
    Easterbrook, D.J., 2011, Geologic evidence of recurring climate cycles and their
    implications for the cause of global climate changes: the past is the key to the future: Elsevier.

    D’Aleo, J., and Easterbrook, D.J., 2011, Relationship of multidecadal global temperatures to multidecadal oceanic oscillations: Elsevier.

  61. michael hammer says:

    The data certainly suggests some correlation but note that during the times when the PDO is declining the rate of fall in temperature is less than the rate of rise when the PDO is increasing. Suggests there is some underlying monotonic trend as well. This could be solar but it could conceivably also be CO2 – we dont know. What is obvious however is that that the monotonic component is FAR less than is claimed by warmists. Even if is were CO2 it might represent AGW certainly not CAGW.

    Also, I note the continuous reference to very long time constants in the climate system. Usually from warmists claiming a lot of future heating is already locked in, we just haven’t seen it yet. Consider however the huge change in temperature both on land and sea between summer and winter. How can a system which has such a long time constant (I have seen predictions of 10’s of decades and even more) respond in a few months. Even more significantly, we can easily tell the seasonal time constant because we know the peak and trough of the insolation precisely – its the solstices. We also know the hottest and coldest times of the year. Here in Australia the hottest time is typically late January and the coldest is typically August. That translates to a lag of about 6-8 weeks. So how come the planet responds in 6-8 weeks to changes in solar energy input yet supposedly takes decades to respond to changes in energy input (or energy retention -same thing really) from other sources. If the time constant was really long and we are in fact seeing only a small portion of the potential seasonal change the lag would be 90degrees or 3 months not half that.

  62. Ivan says:

    The only problem is that Hadcrut 4 is an obvious garbage obtained by “adjusting” drastically upwards the previous version of Hadcrut since 2001, which was already an upward adjustment of previous versions.,

    http://www.woodfortrees.org/plot/hadcrut3vgl/from:2001/trend/plot/hadcrut4gl/from:2001/trend/plot/hadcrut3gl/from:2001/trend/plot/none

  63. Ivan says:

    Actually they decreased the negative trend 2001-2013 from about 0.075 C to 0.025C.

  64. Axel says:

    This is the argument from false cause, or the post hoc ergo propter hoc fallacy. Whilst it may appear that the PDO has a predictive capacity to future global air temperatures, one might also remark that movements of the planet Mars appear to have a predictive capacity to the future course of planet Earth around the Sun.

    Truly there are two sources of heat which ultimately affect the Earth’s “global” air temperature broadly speaking, and they are; 1. internal heat from the Earth’s molten core, manifested in volcanic activity, but also via heat transfer through the bedrock, and; 2. external heat from The Sun. The first process does affect the second process somewhat, by changing the transparency of the Earth’s atmosphere, and subsequent alterations to rainfall patterns, and so on.

    Most significant however is The Sun, our very own Star, our own giant thermo-nuclear reactor which ultimately powers our planetary system. It is the magnetic field, as well as the heat, and Solar particles, which The Sun emits which affect the temperature and weather here on Earth more than anything else. The interaction of the Solar / Lunar magnetic fields, and to a lesser extent similar reactions between the Earth, Mars, Jupiter, and other cosmic events, such as Supernovae, which actually truly have the most significant effect upon the Earth’s stochastic climate system.

    Man’s endeavours are a mere tickle from the leg of an insect, compared to the effects of the vast quantities of all wavelengths of energy that such solar-planetary systems are capable of transferring. The Sun puffs a solar flare of billions of tonnes of material, charged particles and radiation, and we should tremble, and the Earth’s atmosphere expands by three times the volume with the searing heat of the blast. There’s enough power absorbed to run New York for a thousand years. The Moon rises, and the land lifts by three feet, and giant ships float from the sea bed. This is the reality, see it and touch it.

    Wake from your stupor, oh ye hapless victims of Hokum Pathos and False Logos. Remember lastly this, ye are all CARBON BASED Life-forms, whose very existence depends upon free Carbon Dioxide Gas in the Earth’s atmosphere. Pretend no more that ye control the Planet’s weather, for truly it controlleth ye ! Ask no more for ill gotten gains from honest labourers to fund your snake-oil scams, and bogus schemes.

    Enough Already !

  65. Girma says:

    A signature of persistent natural thermohaline circulation cycles in
    observed climate

    Jeff R. Knight,1 Robert J. Allan,1 Chris K. Folland,1 Michael Vellinga,1
    and Michael E. Mann2

    Analyses of global climate from measurements dating
    back to the nineteenth century show an ‘Atlantic
    Multidecadal Oscillation’ (AMO) as a leading large-scale
    pattern of multidecadal variability in surface temperature.
    Yet it is not possible to determine whether these fluctuations
    are genuinely oscillatory from the relatively short
    observational record alone. Using a 1400 year climate
    model calculation, we are able to simulate the observed
    pattern and amplitude of the AMO. The results imply the
    AMO is a genuine quasi-periodic cycle of internal climate
    variability persisting for many centuries, and is related to
    variability in the oceanic thermohaline circulation (THC).
    This relationship suggests we can attempt to reconstruct
    past THC changes, and we infer an increase in THC
    strength over the last 25 years. Potential predictability
    associated with the mode implies natural THC and
    AMO decreases over the next few decades independent
    of anthropogenic climate change.

    http://www.meteo.psu.edu/holocene/public_html/shared/articles/KnightetalGRL05.pdf

  66. Stephen Wilde says:

    A sensible question but not novel.

    “Before it is safe to attribute a global warming or a global cooling effect to any other factor (CO2 in particular) it is necessary to disentangle the simultaneous overlapping positive and negative effects of solar variation, PDO/ENSO and the other oceanic cycles. Sometimes they work in unison, sometimes they work against each other and until a formula has been developed to work in a majority of situations all our guesses about climate change must come to nought.

    So, to be able to monitor and predict changes in global temperature we need more than information about the past, current and expected future level of solar activity.

    We also need to identify all the separate oceanic cycles around the globe and ascertain both the current state of their respective warming or cooling modes and, moreover, the intensity of each, both at the time of measurement and in the future.

    Once we have a suitable formula I believe that changes in global temperature will no longer be a confusing phenomenon and we will be able to apportion the proper weight to other influencing factors such as the greenhouse effect of CO2.”

    from here:

    http://climaterealists.com/index.php?id=1302&linkbox=true&position=10

    “The Real Link Between Solar Energy, Ocean Cycles and Global Temperature”
    Wednesday, May 21st 2008, 8:20 AM EDT

  67. Stephen Wilde says:

    The Pacific Multidecadal Oscillation (PMO – not PDO since the latter is only a measure of pressure variation between locations) is, I think, driven by solar variations altering global cloudiness and albedo in the manner I have suggested previously.

    The change in the amount of solar energy entering the oceans is dependent on global cloudiness and albedo which is in turn dependent on the length of the lines of air mass mixing between climate zones.

    Meridional jets produce longer such lines, more clouds and less energy into the oceans.

    Zonal the opposite.

    When the jets are meridional the reduction in energy into the oceans weakens El Nino events relative to La Nina events. That is what we have been seeing since 2000. It also matches the Maunder Minimum, the Dalton and all the other cooling spells.

    When zonal, the opposite. That is what we were seeing pre 2000.and during the MWP.

    The solar effect on the ENSO process takes about ten years to filter through to the Arctic Ocean so as to effect ice melt.

    The 1998 El Ninos reached the Arctic around 2007 for record melt.

    The 2012 high melt being due to El Ninos in 2002 /03

    http://ggweather.com/enso/years.htm

    So, with a suitable lag period we should be able to broadly anticipate Arctic ice melt from previous El Nino events

  68. Theo Goodwin says:
    June 5, 2013 at 7:48 pm

    “Climate Science is in it’s infancy”
    I’m not certain Climate Science is causing morning sickness yet.

  69. Brian says:

    I became interested in the PDO about 5 years ago, back then I eye-balled the correlation to just shy of 80%. Having just finished my Electrical Engineering degree and with the suggestion of Anthony W, will be beginning a degree in Applied Meteorology in August, so my skills in statistics are getting better every day. I now from the above graph see a correlation of mid 80’s, I still do not have the math skills or patience to mathematically prove my calibrated eye yet.

    One of our previous commentors talked about a divergence between HADCRUT4 and JISAO, this should be expected. JISAO uses SST’s for PDO which is lower variability from land based temps. You would expect HADCRUT4 a combination of land based and SST to have a higher variation than a pure SST – JISAO data set. So I am sure the author of this article was not looking for an exact replica of rate of change.

    One of the things we should look for is that the last ‘strong’ PDO (approx 1945-1977) caused a temp change of approx .25C, during a time when solar output was at its peak for the past century, cycle 19. So if there is not a double peak to cycle 24 and solar output continues to drop off for the next 7 years. What will this PDO bring us?

    Second, thing I found quite interesting, is the correlation between strong ENSO’s and PDO, it is a negative correlation. The author of this paper, uses 1997 as the start point for this ‘stronger’ cycle of PDO for two reasons, the author of “A Pacific Interdecadel Climate Oscillation with Impacts on Salmon Production”, ended his study in 97, and said “1977 through (at least) the mid-1990’s” was a ‘weaker’ PDO(Mantua, 1997). Looking at the JISAO data, quite possibly, the weaker PDO of 1977 might have continued through 2005, and the reason we saw a drop in temps around ’98 was correlated to the El Nino of that time and not a phase shift in PDO. If the stronger PDO started in 05, we could be looking at 20 more years of stasis or cooling temps.

    Thanks to Anthony W, for all the great work, I became a skeptic in mid Nov 06 as I could not justify Gavin Schmidt’s comments of “warmest Oct ever (06)”, that day I found a video “the great Global Warming Swindle”, and just days after that the alarmist had to retract their statement of warmest Oct ever, then again it was not their fault, it was faulty data, scientists have no responsibility to vet data, especially before running to the media. Thanks again for the great work here and suggestion of MSU’s program!

  70. Willis Eschenbach says:

    Well, if you look at the full record, the correlation is worse … but I don’t think you realize what you are doing.

    The JISAO defines the PDO as the leading principle component of the sea surface temperature of the Pacific north of 20N … so it is nothing more than a measure of SST over the North Pacific.

    As a result you are simply comparing the temperature of the whole world with the temperature of a bit less than a quarter of the world.

    I would be extremely surprised of the temperature of maybe 20% of the planet did NOT correlate with the temperature of the whole planet … but as for the odds on the part (North Pacific) having predictive power for the whole planet, I’d be surprised.

    w.

  71. Axel says:

    Precisely, and well analysed Willis Eschenbach !

    Most of what is argued in here is simply trivial prattle.
    Frankly it is irrelevant, even though it may be of some academic interest.
    An interesting song from the seventies by the Brit-pop band, The Stranglers,
    which was not thought to be so controversially radical at the time, now takes
    on some new significance. Listen to the prophetic lyrics in this YouTube clip.

    .http://www.youtube.com/watch?v=Um9kd-mhhK4

  72. kadaka (KD Knoebel) says:

    From Axel on June 5, 2013 at 10:44 pm:

    Truly there are two sources of heat which ultimately affect the Earth’s “global” air temperature broadly speaking, and they are; 1. internal heat from the Earth’s molten core, manifested in volcanic activity, but also via heat transfer through the bedrock, and; 2. external heat from The Sun. The first process does affect the second process somewhat, by changing the transparency of the Earth’s atmosphere, and subsequent alterations to rainfall patterns, and so on.

    Out in Wisconsin or Siberia, you get winter temps down to -30°F, but about ten to twelve feet down the temps will be in the low 50’s. Heat transfer “through the bedrock” is too slow to matter. Heat moves so slowly through the earth, there are geothermal heat pump systems that in summer will store the “waste” heat from cooling underground, where it is recovered in winter for heating.

    The effects of volcanoes are variable, some yield warming, some cooling. Offhand the net effect on global temperature is nothing, the Earth tends to compensate quickly.

    Your “first process” is irrelevant.

    The interaction of the Solar / Lunar magnetic fields, and to a lesser extent similar reactions between the Earth, Mars, Jupiter, and other cosmic events…

    The lunar magnetic field is virtually non-existent, just crustal magnetization. There is no spinning dynamo core, no dipolar field. The “interaction of the Solar / Lunar magnetic fields” is such a tiny weak thing, so completely negligible compared to the vastly more immense magnetic field of Earth, it is hardly worth mentioning outside of a theoretical discussion.

    The Moon rises, and the land lifts by three feet, and giant ships float from the sea bed. This is the reality, see it and touch it.

    The ocean water might move, the land much less so. As to the tides:

    The theoretical amplitude of oceanic tides caused by the moon is about 54 centimetres (21 in) at the highest point, which corresponds to the amplitude that would be reached if the ocean possessed a uniform depth, there were no landmasses, and the Earth were rotating in step with the moon’s orbit. The sun similarly causes tides, of which the theoretical amplitude is about 25 centimetres (9.8 in) (46% of that of the moon) with a cycle time of 12 hours. At spring tide the two effects add to each other to a theoretical level of 79 centimetres (31 in), while at neap tide the theoretical level is reduced to 29 centimetres (11 in). Since the orbits of the Earth about the sun, and the moon about the Earth, are elliptical, tidal amplitudes change somewhat as a result of the varying Earth–sun and Earth–moon distances. This causes a variation in the tidal force and theoretical amplitude of about ±18% for the moon and ±5% for the sun. If both the sun and moon were at their closest positions and aligned at new moon, the theoretical amplitude would reach 93 centimetres (37 in).

    With everything lined up, on an idealized Earth, with Sun and Moon working together, you might get that three feet of lift from water. The land is much less flexible than water, nor does it flow as well. You will not get the Moon lifting the land by three feet.

    Plus given the amount of sediment found deposited on old wrecked ships, leading to their being buried, it is quite obvious that giant ships DO NOT float from the sea bed.

    Who are you to come here and leave such anti-scientific easily-disproved dreck littering the comments, your little pet theories, while rattling on like you’re one of us?

    Hopefully Leif or Willis or one of the other main luminaries of the site will come by and put you out of your misery, by directing you towards real knowledge rather than what you have spewed.

  73. briancd160 says:

    Willis,

    Here is a definition of PDO:
    “A PDO definition
    The Pacific Decadal Oscillation, or PDO, is often described as a long-lived El Niño-like pattern of Pacific climate variability (Zhang et al. 1997). As seen with the better-known El Niño/Southern Oscillation (ENSO), extremes in the PDO pattern are marked by widespread variations in Pacific Basin and North American climate. In parallel with the ENSO phenomenon, the extreme phases of the PDO have been classified as being either warm or cool, as defined by ocean temperature anomalies in the northeast and tropical Pacific Ocean.
    Two main characteristics distinguish the PDO from ENSO. First, typical PDO “events” have shown remarkable persistence relative to that attributed to ENSO events – in this century, major PDO eras have persisted for 20 to 30 years (Mantua et al. 1997, Minobe 1997). Second, the climatic fingerprints of the PDO are most visible in the North Pacific/North American sector, while secondary signatures exist in the tropics – the opposite is true for ENSO. Several independent studies find evidence for just two full PDO cycles in the past century (e.g. Mantua et al. 1997, Minobe 1997): cool PDO regimes prevailed from 1890-1924 and again from 1947-1976, while warm PDO regimes dominated from 1925-1946 and from 1977 through (at least) the mid-1990’s. Recent changes in Pacific climate suggest a possible reversal to cool PDO conditions in 1998, an issue that is discussed in more detail at the end of this article.”

    We all should have reason to question any SST older than 40 years ago as sampling is sparse, one of the big contributors to WUWT Bob Tisdale agrees with this as do many other scientist. For you to say “Well, if you look at the full record, the correlation is worse … but I don’t think you realize what you are doing.” We are for intents and purposes looking at most of the record. In a paper I wrote for school in ’10, I used the correlation of PDO back to 1880 to demonstrate trends in GMT, in my paper I used a lag of average 8 years, the author of this paper is using 5 years, albeit opposite direction as me. From 1880, till present, there is a high correlation of PDO to temp, like I said eye-balling it high 70’s.

    Prior to reading this article, I had always felt that the phase change was within (after) 8 years of temps change, so that is where I ran with the correlation. Looking at this data and seeing the graphs now shows that it looks like, PDO changes and approx a year later temps follow, the change you do not see is the phase change around 1942 graphically PDO (1947 Mantua) and temps HADCRUT4 1945 was about 3 years.

    So the question becomes could PDO be a climate driver? Some scientist believe that PDO is driven by ocean current oscillations and that a ‘strong’/ cool PDO is caused by upwelling of deeper colder pacific water. While, ‘weaker’/ warm PDO is less up-welling, similar to El Nino/ La Nina just on a longer time scale (months as compared to decades). We all know that a large body water can cause local weather to be enhanced by the temp of that water, growing up in Eastern Mass, we would head out to the beach when it was scorching in my backyard, about 10 miles from the water. The last turn to “Nantaskett’ beach you sometimes got a rude awakening, fog and temps dropping 20 degrees within a mile. So the question remains, can a body of water as large as the Pacific, change the weather/ climate of a large portion of the globe. Certainly Mantua believes so, http://www.atmos.washington.edu/~mantua/REPORTS/PDO/PDO_cs.htm.

    I do agree with you, I have alot to learn, that might be why I am enrolled in a Applied Meteorology program (could not find an adequate Atmospheric sciences course 100% online). I do need more understanding of statistics, I wish I could work with data at the level you do, give me a couple years you will see a marked improvement on my posts. Thanks to you also for your informative posts, I enjoy them greatly.

  74. Rob says:

    Excellent. The pioneering work of Namais suggest this also. The PNA/PNO pattern seems to modulate ENSO, thereby driving natural climate cycles globally. The cooling of the 1960’s and 70’s…the warming of the 1980’s and 90’s. And lastly…the present climatic cooling.

  75. Gail Combs says:

    Steven Mosher says: @ June 5, 2013 at 3:40 pm
    ….Put another way. PDO is the effect.
    >>>>>>>>>>>>>>>>>>
    And since the SUN (graph 1 and graph 2 and graph 3) is what warms the oceans and not CO2 that makes the sun the primary driver.

    Glad we finally got that clear.

  76. Ian Wilson says:

    kadaka (KD Knoebel)

    I believe that you would have made an excellent consultant to the Inquisition of the Catholic Church in 1616 under Pope Paul V.

    If you put your resume in quickly you might get a job on the Front Bench of the Inquisition of Pope Urban VIII.

  77. DB says:

    Most here will find the 2002 paper by Bratcher and Giese interesting. Bob Tisdale covers it here:
    http://bobtisdale.wordpress.com/2009/04/10/revisiting-bratcher-and-giese-2002/
    Abstract:
    “An analysis of ocean surface temperature records show that low frequency changes of tropical Pacific temperature lead global surface air temperature changes by about 4 years. Anomalies of tropical Pacific surface temperature are in turn preceded by subsurface temperature anomalies in the southern tropical Pacific by approximately 7 years. The results suggest that much of the decade to decade variations in global air temperature may be attributed to tropical Pacific decadal variability….

  78. Gail Combs says:

    Manfred says: @ June 5, 2013 at 7:20 pm

    ….Some recently came up with the idea, that heat is currently sequestered into the deep ocean and will return and drive temperatures up in a couple of years or decades….
    >>>>>>>>>>>>>>>>>>>>>
    Which is a load of bovine feces.

    1. CO2 lags temperature by about 800 years. link

    2. NOAA: The global ocean conveyor belt is a constantly moving system of deep-ocean circulation driven by temperature and salinity… It takes almost 1,000 years for the conveyor belt to complete one “cycle.”

    3. Medieval Warm period: A flurry of recent scientific papers has tried to measure the warmth of the “Medieval Warm Period” (MWP) of about 1,000 years ago…. papers such as Evidence of a Medieval Warm Period in Antarctica and Evidence for a ‘Medieval Warm Period’ in a 1,100 year tree-ring reconstruction of past austral summer temperatures in New Zealand

    4. A new paper titled High-resolution sea surface reconstructions off Cape Hatteras over the last 10 ka discussion at WUWT

    ABSTRACT
    This study presents high-resolution foraminiferal-based sea surface temperature, sea surface salinity and upper water column stratification reconstructions off Cape Hatteras, a region sensitive to atmospheric and thermohaline circulation changes associated with the Gulf Stream… We observed opposite evolutions between the conditions off Cape Hatteras and those south of Iceland, known today for the North Atlantic Oscillation pattern. We interpret the temperature and salinity changes in both regions as co-variation of activities of the subtropical and subpolar gyres….We demonstrate, for the 5.2–3.5 ka period, that the salinity increase was caused by the cessation of the low salinity surface flow coming from the north. A northward displacement of the Gulf Stream, blocking the southbound low-salinity flow, concomitant to a reduced Meridional Overturning Circulation is the most likely scenario. Finally, wavelet transform analysis revealed a 1000-year period pacing the δ18O signal over the early Holocene. This 1000-year frequency band is significantly coherent with the 1000-year frequency band of Total Solar Irradiance (TSI) between 9.5 ka and 7 ka and both signals are in phase over the rest of the studied period.

  79. Gail Combs says:

    rgbatduke says:
    June 5, 2013 at 7:33 pm

    ….Let me amend that — I don’t completely reject data from earlier measurements, but I pay it little attention when it is presented (as it always is) without error bars….
    >>>>>>>>>>>>>>
    If they ever put in the error bars and scaled the graphs correctly the whole subject/alarm goes away. AJ Strata looked at the actual error bars in the temperature data here.

    One of the sleight of hand moves is to consider the temperature as averages when each measurement is actually an individual measurement of a specific time and place and is not replicated. This alone widens the error bars to 1 degree in much of the data since measuring and reporting to tenths of a degree is recent and not world wide – An independent audit team has just produced a report showing that as many as 85 -95% of all Australian sites in the pre-Celsius era (before 1972) did not comply with the BOM’s own stipulations. The audit shows 20-30% of all the measurements back then were rounded or possibly truncated. Even modern electronic equipment was at times, so faulty and unmonitored that one station rounded all the readings for nearly 10 years…

  80. briancd160 says:

    Willis,

    Here is a definition of PDO:
    “A PDO definition
    The Pacific Decadal Oscillation, or PDO, is often described as a long-lived El Niño-like pattern of Pacific climate variability (Zhang et al. 1997). As seen with the better-known El Niño/Southern Oscillation (ENSO), extremes in the PDO pattern are marked by widespread variations in Pacific Basin and North American climate. In parallel with the ENSO phenomenon, the extreme phases of the PDO have been classified as being either warm or cool, as defined by ocean temperature anomalies in the northeast and tropical Pacific Ocean.
    Two main characteristics distinguish the PDO from ENSO. First, typical PDO “events” have shown remarkable persistence relative to that attributed to ENSO events – in this century, major PDO eras have persisted for 20 to 30 years (Mantua et al. 1997, Minobe 1997). Second, the climatic fingerprints of the PDO are most visible in the North Pacific/North American sector, while secondary signatures exist in the tropics – the opposite is true for ENSO. Several independent studies find evidence for just two full PDO cycles in the past century (e.g. Mantua et al. 1997, Minobe 1997): cool PDO regimes prevailed from 1890-1924 and again from 1947-1976, while warm PDO regimes dominated from 1925-1946 and from 1977 through (at least) the mid-1990′s. Recent changes in Pacific climate suggest a possible reversal to cool PDO conditions in 1998, an issue that is discussed in more detail at the end of this article.”

    We all should have reason to question any SST older than 40 years ago as sampling is sparse, one of the big contributors to WUWT Bob Tisdale agrees with this as do many other scientist. For you to say “Well, if you look at the full record, the correlation is worse … but I don’t think you realize what you are doing.” We are for intents and purposes looking at most of the record. In a paper I wrote for school in ’10, I used the correlation of PDO back to 1880 to demonstrate trends in GMT, in my paper I used a lag of average 8 years, the author of this paper is using 5 years, albeit opposite direction as me. From 1880, till present, there is a high correlation of PDO to temp, like I said eye-balling it high 70′s.

    Prior to reading this article, I had always felt that the phase change was within (after) 8 years of temps change, so that is where I ran with the correlation. Looking at this data and seeing the graphs now shows that it looks like, PDO changes and approx a year later temps follow, the change you do not see is the phase change around 1942 graphically PDO (1947 Mantua) and temps HADCRUT4 1945 was about 3 years.

    So the question becomes could PDO be a climate driver? Some scientist believe that PDO is driven by ocean current oscillations and that a ‘strong’/ cool PDO is caused by upwelling of deeper colder pacific water. While, ‘weaker’/ warm PDO is less up-welling, similar to El Nino/ La Nina just on a longer time scale (months as compared to decades). We all know that a large body water can cause local weather to be enhanced by the temp of that water, growing up in Eastern Mass, we would head out to the beach when it was scorching in my backyard, about 10 miles from the water. The last turn to “Nantaskett’ beach you sometimes got a rude awakening, fog and temps dropping 20 degrees within a mile. So the question remains, can a body of water as large as the Pacific, change the weather/ climate of a large portion of the globe. Certainly Mantua believes so, http://www.atmos.washington.edu/~mantua/REPORTS/PDO/PDO_cs.htm.

    I do agree with you, I have alot to learn, that might be why I am enrolled in a Applied Meteorology program (could not find an adequate Atmospheric sciences course 100% online). I do need more understanding of statistics, I wish I could work with data at the level you do, give me a couple years you will see a marked improvement on my posts. Thanks to you also for your informative posts, I enjoy them greatly.

  81. Paul Vaughan says:

    Ian Wilson (June 5, 2013 at 6:01 pm) wrote:

    “Long-Term Lunar Atmospheric Tides in the Southern Hemisphere
    Ian R. G. Wilson and Nikolay S. Sidorenkov
    The Open Atmospheric Science Journal, 2013, 7, 51-76

    http://www.benthamscience.com/open/toascj/articles/V007/TOASCJ130415001.pdf

    Relevant part of .ABSTRACT

    Finally, an N=4 standing wave-like pattern in the MSLP that circumnavigates the Southern Hemisphere every 18.6 years will naturally produce large extended regions of abnormal atmospheric pressure passing over the semi-permanent South Pacific subtropical high roughly once every ~ 4.5 years. These moving regions of higher/lower than normal atmospheric pressure
    will increase/decrease the MSLP of this semi-permanent high pressure system, temporarily increasing/reducing the strength of the East-Pacific trade winds. This may led to conditions that preferentially favor the onset of La Nina/El Nino events.”

    If you are correct, there will be a constraint determined by the beat of 4.5 years with the nearest subharmonic of the terrestrial year — specifically:

    (5)*(4.5) / (5 + 4.5) = 2.37 years

    ___

    @ rgb

    You need to brush up on your understanding of what PDO measures.

  82. Gary Pearse says:

    rgbatduke says:
    June 5, 2013 at 5:12 pm

    Post hoc ergo propter hoc. When an argument is a named logical fallacy, why make it?….
    ….Why is it so very difficult to say “we don’t know”?

    A tour de force rgb!! I mean the stuff you wrote between the two questions of course. Your sobering offerings always stand out a mile, but this is because such a way of thinking by a generation (or more?) of “post-normal” (horrid science-killing concept) scientists has become all too rare. Or (hopefully) there are more of you out there but keeping their silence. Man, If I had a few billion bucks, I would fund an independent scientific research center, people it with the best I could find, let their research take them where it may and put you in charge.

  83. ferd berple says:

    Steven Mosher says:
    June 5, 2013 at 3:40 pm
    PDO is temperature. predicting temperature from temperature tells you nothing.
    =============
    Exactly. Just like climate models predicting future temperatures from current and past temperatures, they tell you nothing.

    However, in this case the author is using lag, not temperature to make a prediction. The prediction is that PDO leads global temps by 5 years, and thus one can use the trend in the PDO to predict the trend in global temps 5 years in advance. Which is a whole lot better than climate models have been able to do.

    This doesn’t mean or require that the PDO causes global temps to vary, but it could. My suspicion is that the PDO reflects an oscillation in deep ocean mixing rate, the ocean conveyor that surfaces after a 1000 years of travel between the poles and eastern Pacific. When the tail end of this flow slows, the Pacific warms first, then the rest of the globe follows. When the tail end speeds up, the Pacific cools, then the rest of the globe follows. Thus the lag between the PDO and global temps.

    We see a (quasi) cyclic timing in this oscillation likely because it beats in time with some orbital harmonics, that are co-incidentally tuned to some natural frequency of the oceans. Whether this effect is direct, such as the effect of the orbital plane of the moon on the distribution of water in the oceans, or indirect as a result of near integer resonance of the planets on the solar cycle, there is no lack of conjecture.

    As far as prediction goes, our current knowledge of mathematics indicates we are a long ways from being able to reliably calculate climate from first principles, even if we did have good historical data. The current climate models demonstrate this failing in spades and are a scam of global proportions, as they continue to drift further and further away from reality. The Farmers Almanac is a more reliable guide, and costs about $100 million less.

  84. herkimer says:

    The PDO index reflects the degree to which observed SSTs across the entire N. Pacific resemble a reference pattern (that pattern was derived in an EOF analysis). The pattern is basically an east-west see-saw, and the PDO index has large negative values when the N. Pacific is both warmer than average in the western N. Pacific and colder than average along the Pacific coast, the situation we currently have. Does anyone really think that a pattren of more colder water along our west coast than in the western Pacific will have no effect on our west coast temperatures or the weather that blows in from the Pacific. Of course it will.

    A more negative PDO index is typically a result of both more negative SST anomalies in the NE Pacific in combination with more positive SST anomalies in the central north Pacific.

    It is possible that this changing pattern of SST in the North Pacific together with the AMO temperature pattern in the North Atlantic can and does have a significant impact on North American weather and temperatures , which in turn and via air circulations cross the Atlantic and will affect Europe as well . So it is quite possible in my judgment that PDO index can have predictive value for global temperatures.

  85. ferdberple says:

    Paul Vaughan says:
    Finally, an N=4 standing wave-like pattern in the MSLP that circumnavigates the Southern Hemisphere every 18.6 years
    ==========
    The precession of the plane of the lunar orbit is 18.6 years, which would certainly affect the oceans and the currents within. It could even result in resonance and cycles; oscillations if you will.

  86. herkimer says:

    From a PNAS paper by G.j McCabe et al called PACIFIC AND ATLANTIC OCEAN INFLUENCES ON MULTIDECADAL DROUGHT FREQUENCYIN UNITED S ATES [2004

    Abstract

    More than half (52%) of the spatial and temporal variance in multidecadal drought frequency over the conterminous United States is attributable to the Pacific Decadal Oscillation (PDO) and the Atlantic Multidecadal Oscillation (AMO). An additional 22% of the variance in drought frequency is related to a complex spatial pattern of positive and negative trends in drought occurrence possibly related to increasing Northern Hemisphere temperatures or some other unidirectional climate trend. Recent droughts with broad impacts over the conterminous U.S. (1996, 1999-2002) were associated with North Atlantic warming (positive AMO) and northeastern and tropical Pacific cooling (negative PDO). Much of the long-term predictability of drought frequency may reside in the multidecadal behavior of the North Atlantic Ocean. Should the current positive AMO (warm North Atlantic) conditions persist into the upcoming decade, we suggest two possible drought scenarios that resemble the continental-scale patterns of the 1930s (positive PDO) and 1950s (negative PDO) drought.

  87. Ian Wilson says:

    Paul,

    The exact figure is 4.65 years (= 18.6 years / 4), so following your suggestion you would get:

    ((5 * 4.65) / (5 + 4.65) = 2.41 years = 28.9 months

    which has roughly the mean period of the QBO.

    I see oscillation in the strength of the moving N=4 standing wave that is sometimes biennial and sometimes triennial – which I would think average out to roughly ~ 2.5 years.

  88. @rgbatduke

    I agree heartily with your enumeration of things we don’t know. It is extremely strange to observe the disconnect between the absolutely daunting complexity of the climate and the notion of supposedly settled science that still dominates the public’s perception.

    As to your question: Why is it so very difficult to say “we don’t know?” That is psychology — we would be admitting defeat. Species did not advance in evolution by admitting defeat, and acceptance of defeat is shunned equally by human instincts and the human mind. This does, of course, produce deplorable results. Francis Bacon said it well:

    Those who have taken upon them to lay down the law of nature as a thing already searched out and understood, … have therein done philosophy and the sciences great injury. For as they have been successful in inducing belief, so they have been effective in quenching and stopping inquiry.

    His words remain true even in our supposed age of enlightenment. When I was at med school, the supposed cause of ulcers was stress, and an entire cathedral full of psychosomatic pontification had been erected around this supposition. Against this fortified position, it was an uphill battle for the truth — the real cause of ulcers is a pesky bacterium, Helicobacter pylori. Why should rational climate scientists have it any easier than Marshall and Warren, the two brave Aussie champions of this humble bug …

    BTW I just set another bad example … I really don’t know the answer to the question, so I made it up ;)

  89. Duster says:

    It is really rather interesting to note the array of “definitions” of the PDO in this thead. There is everything from Steve Mosher’s “temperature” to Willis’ assertion that it is a principal component of sea surface temperature distribution patterns within a given region. It seems to me that a discussion would benefit from people settling down and settling on a common definition of just what is meant by PDO, QDO, IDO, ENSO and the rest of the alphabet soup. You want to remember that the PDO was not detected by either meteorologists or climatologists, but rather by a fisheries guy who noted patterns in west coast salmon runs. So, possibly it’s the salmon who have always controlled climate. I wish to be the first to salute our scaly overlords. ;-)

  90. ralfellis says:

    I’ve been saying this for years – ever since WUWT introduced me to the cycles of the PDO. It just seemed obvious.

    .

  91. Resourceguy says:

    I would have to agree that modeling a temperature term with a temperature term is problematic. Perhaps it would be time to move on to AMO vs. northern sea ice anomaly. Adding a probit qualitative terms for which side of the Arctic ice sheet is low compared to high AMO could also be tested.
    Visually, it looks like this from the WattsUp reference pages on sea ice and AMO….
    Surely, no one is going to say temperature does not effect ice!

    http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.anomaly.arctic.png

    http://www.climate4you.com/images/NOAA%20SST-NorthAtlantic%20GlobalMonthlyTempSince1979%20With37monthRunningAverage.gif

  92. herkimer says:

    duster

    the PDO index tracks a pattern of SST anomalies that, when it is cold in the western and central part of the N. Pacific, and warm in the eastern part of the N. Pacific, the index has positive values and is negative when the pattern is opposite to the above, The question that this track asks is whether changes in these patterns are of predictive value in predicting changes to global temperatures as well . Those who have observed and analyzed the index and the global temperatures say that they have noted the relationship to be of value even though the connection is not fully yet explained or appreciated.. I tend to agree . . The key is that pdo is an index of pattrens and not a direct tempertaure index. Because this pattern seems to have a somewhat of a repetitive nature recently [ 30 years positive and 30 years negative] , it is currently heading down[negative since 2007] and may trough by about 2030. Is this indicating that global climate will do the same and trough as well ?. Maybe. Global temperatures peaked about 2000-2010 and are heading down.[ see recent posts on this]

  93. Duster says:

    I still suggest a closer look at the Salmon.

  94. Willis Eschenbach says:

    Duster says:
    June 6, 2013 at 10:17 am

    It is really rather interesting to note the array of “definitions” of the PDO in this thead. There is everything from Steve Mosher’s “temperature” to Willis’ assertion that it is a principal component of sea surface temperature distribution patterns within a given region.

    I did not “assert” that the PDO “is a principal component of sea surface temperature distribution patterns within a given region”.

    I said that’s the measurement index of the PDO that was used in the head graph. The graph uses the JISAO PDO Index, which uses the leading PC as I reported (not “asserted”).

    There are several other ways to measure the PDO. I should probably write a post on the subject.

    It seems to me that a discussion would benefit from people settling down and settling on a common definition of just what is meant by PDO, QDO, IDO, ENSO and the rest of the alphabet soup.

    Mmmm … that would be one of the reasons for the post. In the meantime, it’s important to distinguish and disambiguate several things:

    1. What the PDO is.

    2. What the PDO does.

    3. How the PDO is measured.

    You want to remember that the PDO was not detected by either meteorologists or climatologists, but rather by a fisheries guy who noted patterns in west coast salmon runs. So, possibly it’s the salmon who have always controlled climate. I wish to be the first to salute our scaly overlords. ;-)

    You’re preaching to the choir on that one, duster …

    w.

  95. Willis Eschenbach says:

    briancd160 says:
    June 6, 2013 at 1:14 am

    We all should have reason to question any SST older than 40 years ago as sampling is sparse, one of the big contributors to WUWT Bob Tisdale agrees with this as do many other scientist. For you to say “Well, if you look at the full record, the correlation is worse … but I don’t think you realize what you are doing.” We are for intents and purposes looking at most of the record.

    Eric Worrall asked in the lead post whether the result was due to “bad endpoint choice”, so I thought I’d look at a larger record.

    However, the “you don’t realize” was about the following thought, which was that they are only comparing the temperature of the whole with the temperature of the part …

    In a paper I wrote for school in ’10, I used the correlation of PDO back to 1880 to demonstrate trends in GMT, in my paper I used a lag of average 8 years, the author of this paper is using 5 years, albeit opposite direction as me. From 1880, till present, there is a high correlation of PDO to temp, like I said eye-balling it high 70′s.

    That’s like saying the temperature of your living room has a “high correlation” with the temperature of your house. You are comparing Pacific temperatures with global temperatures, and I’d be shocked if they were NOT well correlated.

    … So the question becomes could PDO be a climate driver?

    To understand the PDO, you have to look at its effect, but not on temperature directly. You need to look at how it affects the functioning of the climate system.

    The earth loses much of its heat by moving it (via a number of paths) to the poles. One of the major paths is through the movement of warm water to the poles in the Pacific. The two states of the PDO (warm and cold) reflect re-arrangements of the oceanic currents that either assist or impede the flow of warm water from the tropical Pacific to the poles.

    I’ll expand on this thought in an upcoming post,

    w.

  96. Paul Vaughan says:

    @ Girma (June 6, 2013 at 7:01 am)

    It’s a very well known result:
    https://pantherfile.uwm.edu/kravtsov/www/downloads/Presentations2010-2011/AMO_AGU10.pdf

    I sure hope you didn’t overlook something that simple.

  97. Paul Vaughan says:

    @ Ian Wilson

    Saros? I’m going to have to look into this far more carefully if/when time/resources ever permit…

  98. Paul Vaughan says:

    @ Girma

    Be careful interpreting the linked summary. Attribution is misplaced. AMO/AMOC = locally amplified manifestation (not driver). The phenomenon is global and externally governed.

    http://tallbloke.files.wordpress.com/2013/03/scd_sst_q.png

    Interpretive Caution: Temporal cycle acceleration/deceleration indicates spatiotemporal acceleration/deceleration more generally due to a simple relationship:
    http://iopscience.iop.org/0004-637X/589/1/665/fulltext/57538.fg2.html

    i.e. rate of change of rate of solar spatial pattern change = SCD

  99. feet2thefire says:

    @rgbatduke June 5, 2013 at 5:12 pm:
    “If the Pacific is almost half of the globe, and the PDO is a monotonic transform of the temperature of the Pacific as he seems to assert, why does global average temperature lag the average temperature of the Pacific?”

    I looked up the WHOLE Pacific one time, and the number was 32%, which is about 1/3, not 1/2 the globe.

    I’ve been up on this for a decade or so, and the PDO is NOT the entire Pacific, only the northern part of the northern half. Think in terms of north of Hawaii. Willis talks about it here as extending from the ENSO region to the upper reaches of the Pacific, but that is not how I know it. Perhaps someone has widened the definition when I wasn’t looking.

    At the same time, the ocean north of Hawaii is itself a HUGE area, somewhat larger than Russia. It is the biggest monolithic named element in the climate equation, and being so large it is like an elephant in the room – the one that has pretty much been ignored, especially by warmists, who would lose a lot of their arguing points if a new natural element was seen as contributing so much. By comparison with the PDO any emissions by mankind are almost infinitesimally minuscule – CO2 or otherwise.

    Of COURSE an element that large is going to affect the entire global temps – in ways far exceeding anything else. The PDO is several times larger than ENSO, so its effects should be relatively proportional. And humans have no effect on ENSO. ENSO leads. PDO also leads, as this shows. The 5-year lag mentioned here seems just about right, based on when the regime change occurred.

    Willis has a nice concept here, tying ENSO and the PDO. It is certainly worth someone looking into some day. I would guess that with so much funding going into CAGW there is precious little funding left for real science.

    …Steven Mosher asserts out that the PDO is part of the global temps, and therefore (he says) it is obvious that it is the same. That isn’t true, even on the face of it. Only SOME other areas of the globe swing up and down with the global averages. The evidence doesn’t show all of the regions in phase with the global. But with the terrible siting that Anthony points out in the US (still by far the most well-covered area), who knows WHAT the real regional phases do relative to the global.

    People who knew about the PDO ten years ago (long before anyone else) were already predicting this present slowdown/pause/slight decline, specifically because of the regime change that occurred in the PDO from cool to warm, which they anticipated and then detected. And they have been spot on. And even with their rudimentary knowledge about the PDO they said the change would last from 20-30 years, if not more. So we are 1/3 or 1/2 the way through that.

    Steve Garcia

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