Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings


All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Donate

Twitter Facebook YouTube Pinterest

RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
Keep me logged in
New? Register here
Forgot your password?

Latest Posts

Archives

Climate Hustle

Global warming and the El Niño Southern Oscillation

What the science says...

The El Nino Southern Oscillation shows close correlation to global temperatures over the short term. However, it is unable to explain the long term warming trend over the past few decades.

Climate Myth...

It's El Niño
"Three Australasian researchers have shown that natural forces are the dominant influence on climate, in a study just published in the highly-regarded Journal of Geophysical Research. According to this study little or none of the late 20th century global warming and cooling can be attributed to human activity. The close relationship between ENSO and global temperature, as described in the paper, leaves little room for any warming driven by human carbon dioxide emissions. The available data indicate that future global temperatures will continue to change primarily in response to ENSO cycling, volcanic activity and solar changes." (Climate Depot)

The paper claiming a link between global warming and the El Niño Southern Oscillation (ENSO)  is Influence of the Southern Oscillation on tropospheric temperature (McLean 2009). What does the paper find? According to one of it's authors, Bob Carter,

"The close relationship between ENSO and global temperature, as described in the paper, leaves little room for any warming driven by human carbon dioxide emissions."

In other words, they claim that any global warming over the past few decades can be explained by El Niño activity.

How do they arrive at this conclusion? They begin by comparing satellite measurements of tropospheric temperature to El Niño activity. Figure 1 plots a 12 month running average of Global Tropospheric Temperature Anomaly (GTTA, the light grey line) and the Southern Oscillation Index (SOI, the black line).


Figure 1: Twelve-month running means of SOI (dark line) and MSU GTTA (light line) for the period 1980 to 2006 with major periods of volcanic activity indicated (McLean 2009).

The Southern Oscillation Index shows no long term trend (hence the term Oscillation) while the temperature record shows a long term warming trend. Consequently, they find only a weak correlation between temperature and SOI. Next, they compare derivative values of SOI and GTTA. This is done by subtracting the 12 month running average from the same average 1 year later. They do this to "remove the noise" from the data. They fail to mention it also removes any linear trend, which is obvious from just a few steps of basic arithmetic. It is also visually apparent when comparing the SOI derivative to the GTTA derivative in Figure 2:


Figure 2: Derivatives of SOI (dark line) and MSU GTTA (light line) for the period 1981–2007 after removing periods of volcanic influence (McLean 2009).

The linear warming trend has been removed from the temperature record, resulting in a close correlation between the filtered temperature and SOI. The implications from this analysis should be readily apparent. El Niño has a strong short term effect on global temperature but cannot explain the long term trend. In fact, this is a point made repeatedly on this website (eg - here and here).

This view is confirmed in other analyses. An examination of the temperature record from 1880 to 2007 finds internal variability such as El Nino has relatively small impact on the long term trend (Hoerling 2008). Instead, they find long term trends in sea surface temperatures are driven predominantly by the planet's energy imbalance.

There have been various attempts to filter out the ENSO signal from the temperature record. We've examined one such paper by Fawcett 2007 when addressing the global warming stopped in 1998 argument. Similarly, Thompson 2008 filters out the ENSO signal from the temperature record. What remains is a warming trend with less variability:


Figure 3: Surface air temperature records with ENSO signal removed. HadCRUT corrections by Thompson 2008, GISTEMP corrections by Real Climate.

Foster and Rahmstorf (2011) used a multiple linear regression approach to filter out the effects of volcanic and solar activity and ENSO.  They found that ENSO, as measured through the the Multivariate ENSO Index (MEI), had a slight cooling effect of about -0.014 to -0.023°C per decade in the surface and lower troposphere temperatures, respectively from 1979 through 2010 (Table 1, Figure 4).  This corresponds to 0.045 to 0.074°C cooling from ENSO since 1979, respectively.  The results are essentially unchanged when using SOI as opposed to MEI.

Table 1: Trends in  °C/decade of the signal components due to MEI, AOD and TSI in the regression of global temperature, for each of the five temperature records from 1979 to 2010.

table 3

Figure 7

Figure 4: Influence of exogenous factors on global temperature for GISS (blue) and RSS data (red). (a) MEI; (b) AOD; (c) TSI.

Like Foster and Rahmstorf, Lean and Rind (2008) performed a multiple linear regression on the temperature data, and found that although ENSO is responsible for approximately 12% of the observed global warming from 1955 to 2005, it actually had a small net cooling effect from 1979 to 2005.  Overall, from 1889 to 2005, ENSO can only explain approximately 2.3% of the observed global warming.

Ultimately, all the data analysis shouldn't distract us from the physical reality of what is happening to our climate. Over the past 4 decades, oceans all over the globe have been accumulating heat (Levitus 2008; Nuccitelli et al. 2012, Figure 5). The El Niño Southern Oscillation is an internal phenomenon where heat is exchanged between the atmosphere and ocean and cannot explain an overall buildup of global ocean heat. This points to an energy imbalance responsible for the long term trend (Wong 2005).

Fig 1

Figure 5: Land, atmosphere, and ice heating (red), 0-700 meter OHC increase (light blue), 700-2,000 meter OHC increase (dark blue).  From Nuccitelli et al. (2012),

Data analysis, physical observations and basic arithmetic all show ENSO cannot explain the long term warming trend over the past few decades. Hence the irony in Bob Carter's conclusion "The close relationship between ENSO and global temperature leaves little room for any warming driven by human carbon dioxide emissions". What his paper actually proves is once you remove any long term warming trend from the temperature record, it leaves little room for any warming.

Intermediate rebuttal written by dana1981


Update July 2015:

Here is a related lecture-video from Denial101x - Making Sense of Climate Science Denial

Last updated on 10 July 2015 by pattimer. View Archives

Printable Version  |  Offline PDF Version  |  Link to this page

Further reading

NOAA have a very useful resource ENSO Cycle: Recent Evolution, Current Status and Predictions which features recent ENSO activity as well as model predictions of ENSO activity in the near future.

Comments

Prev  1  2  3  4  Next

Comments 51 to 100 out of 196:

  1. It is interesting to not the varying scales used by Kayell @49. He uses at least three (possibly four) different inconsistent scales for the Global - East Pacific SST. Not until the sixth graph (the one showing timing of El Nino events, and volcanoes) that he shows a close approximation to the correct scale. His inconsistent scaling is unexplained, and is germain.
  2. IanC says: “PDO (regardless the physical cause) is fundamentally a basin-wide mode of variability over inter-decadal timescale.”

    Incorrect, IanC. The PDO Index is derived from (it's the leading principal component of) the sea surface temperature anomalies of the North Pacific, north of 20N, after the global sea surface temperature anomalies have been removed. By definition it cannot be a “basin-wide mode of variability over inter-decadal timescale” because it does not represent the data of the basin. JISAO includes the basin maps to show the “El Niño like” spatial patterns in the North Pacific (north of 20N). To help with your bearings, look for Hawaii on the maps. It's at about 20N latitude.

    IanC says: “A change of PDO index from 1 to 0 corresponds to a relative cooling of 0.4 degrees over 1982-2010, which is large enough to account of the lack of warming in eastern pacific.”

    Also incorrect, IanC. The PDO does not represent the sea surface temperature anomalies of the North Pacific and it definitely does not represent the sea surface temperatures of the East Pacific. Over decadal timescales the PDO is inversely related to the sea surface temperature anomalies of the North Pacific:
    http://i52.tinypic.com/15oz3eo.jpg

    Please also detail with data how you determined “A change of PDO index from 1 to 0 corresponds to a relative cooling of 0.4 degrees over 1982-2010…” when the PDO does not represent sea surface temperature anomalies in any way, shape or form.

    IanC says: “Your point (d): Is this post the basis of your point? If so, your reasoning is fundamentally flawed, as a correlation does not imply causation, it is equally, if not more, likely that SST anomaly causes a change in air pressue.”

    There’s no flaw in my reasoning or understanding of what causes the PDO. Using different methods, Di Lorenzo came to the same conclusion.

    IanC says: “Regarding ENSO: Your references all appear to be linear regression analyses, which assume that surface temperature respond proportionally to El Niño and La Niña, which is very different from your assertion in post 40, where you said: ‘According to numerous peer-reviewed papers, surface temperatures respond proportionally to El Niño and La Niña events, but it’s obvious they do not.’”

    You’ll need to expand on why it’s different, IanC.
  3. doug_bostrom asked, “…is it the claim of Bob Tisdale that there's no trend in global ocean heat content, or if anything that global ocean heat content has in fact decreased as global surface temperature has increased?”

    Nope.
  4. Intriguing discussion.

    Can Mr. Tisdale please direct us to a peer-reviewed paper in a reputable journal in which he has presented his hypothesis and provided supporting evidence of said hypothesis?

    Talking of journal papers, I think it safe to assume that Mr. Tisdale agrees with and understands exactly how Douglass and Knox (2012) analyzed the OHC data. Additinally, would Mr. Tisdale stake his "reputation" (in the "skeptic" blogosphere) and his hypothesis on the aforementioned paper? He can respond to the last statement and question onthe relevant DK thread.
  5. Further to Bob's reply at #53, I don't see what relevance Bob's ideas have to global warming. If global surface temperature is increasing along with global ocean heat content more or less simultaneously on a scale greater than a decade or so, what's the relevance of ENSO to the long term problem of global warming?

    "Increasing global ocean heat content" means the net warmth of the entire ocean is increasing, which in turn means the notion of energy shifting from one portion of the global ocean to another to produce the false impression of warming doesn't pan out.

    Which I suppose is the point of the rebuttal.

    Presuming that Bob is asserting that the E. tropical Pacific is responsible for warming the entire remaining planet on scales greater than a decade, something else I don't understand is how the E. tropical Pacific could do so without becoming more than a touch cooler itself. It seems we ought to be seeing a relatively drastic cooling of the region but we don't. If anything, we see the opposite.
  6. Bob,

    Yes I understand how the PDO index is constructed. The point is that you can get an idea of how the rest of the basin varies by regressing the SST anomaly (SSTA) onto the PDO index to extract the inter-decadal variation that is associated with the PDO. While the PDO index is constructed using N. pacific data, the subsequent regression demonstrate that there is strong evidence that the tropical Pacific ocean vary coherently with the N Pacific.

    There are ample evidences of a basin-wide inter-decadal oscillation. Here are two:
    Zhang et al. 1997, did an EOF with SSTA of the entire basin . For the low-pass filtered (c.f. fig 3) computation, the dominant mode has a similar spatial structure as the one depicted on the JISAO website. Furthermore, the principal component varies similar to the PDO index.

    Shakun and Shaman 2009 showed that if you do a similar analysis with data from the southern Pacific, and the principal component is again highly correlated to PDO index. Furthermore, they again recover similar spatial structure across the entire pacific ocean.

    Conclusion is that no matter which way you look at it, there appears to be a robust inter-decadal mode of variability in the pacific. The main point is that although looks like the ENSO, there are two distinctive differences:
    - 20-30 years for PDO vs 6-18 months for ENSO.
    - ENSO is most prominent in the tropics, while for PDO the responses in N. Pacific and Tropics are similar in amplitdue.

    PDO index is one of the ways you can characterize this oscillation, the same way SSTA from a limited region (e.g. NINO3.4) can characterize the state of a basin wide oscillation (ENSO).

    Your assertion that the PDO index has no relation to the SSTA is wrong, because one cannot interpret the PDO index (principal component) without concurrently consider the spatial structure (EOF), simply because a mode of variability in an EOF/PC analysis is actually represented by EOF*PC. Here you'll see that you have to choose a normalisation, because if you take c*PC and EOF/c (c is a constant) you get the same thing when you multiple the two together.

    Take a look at the EOF and PC for the PDO (from Deser et al. 2010 :

    Notice that the units for the top panel (the EOF) is in degrees per standard deviation. The PC (PDO index) is given in standard deviation, so to recover the SSTA you indeed have to multiply the two to get the right units.

    The average of the EOF in the N. Pacific definitely negative (<0), but probably no smaller than -0.4. Taking the average you get -0.2 degrees C per SD, which is exactly the scaling factor you found.

    You are technically correct in saying that "PDI index is not SSTA", but you are completely missing the point: the PDI index, in conjunction with the EOF, does in fact describe SST variations.

    In the eastern pacific (as you defined it), if you average the EOF you probably get 0.3 degree per SD. Between 1980-1985 and 2005-2010, the PDO index went from +1 to -0.5, so

    ΔSST= -1.5 * 0.3 = -0.45 degrees C

    you can probably argue for a couple of tenths either way, but the key is that the change in eastern Pacific due to PDO is large enough to explain the lack of warming in the eastern pacific.

    You said "There’s no flaw in my reasoning or understanding of what causes the PDO. Using different methods, Di Lorenzo came to the same conclusion."

    In your blog post, the crux of your argument is fig7, where you plotted 85-month smoothed PDO - Nino3.4 as well as N. Pacific air pressure index (NPI). The figure shows a good correlation between the two series, which you then said "Is The Difference Between NINO3.4 SST Anomalies And The PDO A Function Of Sea Level Pressure?, the answer appears to be yes."

    (1) Nowhere in your analysis did you present an argument of causality..
    (2) In addition, you applied a 85-month filter, which will likely wipe out any signal in ENSO. In fact if you plot a 85-month smoothed PDO index against the NPI I suspect you will get just as good of a result, so likely what you have found is a good correlation between PDO index and NPI.

    Can you post the reference to di Lorenzo?

    Final point:
    In your original post, you said ‘According to numerous peer-reviewed papers, surface temperatures respond proportionally to El Niño and La Niña events'. I think the reasonable interpretation, based on your wording, is that numerous papers concluded that surface temperatures respond proportionally to El Niño and La Niña events; this is very different from papers assuming the same.
  7. Kayell,

    Part 1:

    The main problem here is that you are working with a noisy dataset, and you elected not to apply any statistical test, or even some quantitative measurement. Eyeballing, is not a particular good tool.

    Your claim that "The ENTIRE global rise above the NINO3.4 occurs at two specific instances. Not at any other time." is demonstrably false. Sphaerica shifted the events at La Nina events and produced a plot similar to yours, so is it La Nina?

    I played around with the data, and if I allow myself two shifts, the ones that minimizes the overall difference between the two dataset actually occurs in 1984 and 1996. In this case perhaps the best explanation is volcanoes?

    Simply put, without doing any rigorous analysis, you cannot not rule out other possibilities, so you are not entitled to claim that your interpretation is correct.

    More on part 2 later.
  8. Albatross: “Additinally, would Mr. Tisdale stake his ‘reputation’ (in the 'skeptic' blogosphere) and his hypothesis on the aforementioned paper? He can respond to the last statement and question onthe relevant DK thread.”

    Curious tactic, Albatross. Nice try, but I have no reason to stake my reputation on the work of someone else. Douglass and Knox (2012) analyzed ocean heat content data on a global basis. I typically don’t bother investigating global data. Why? Looking at global data can be misleading. It’s best to divide the oceans into logical subsets, because coupled ocean-atmospherics processes impact ocean basins in significantly different ways. Realistically, that’s the only way anyone can attempt to perform an attribution study on the warming of ocean heat content data--or sea surface temperature data.

    Regards
  9. @Bob Tisdale #58:

    In your response to Albatross, you conveniently ignore the first question hea had posed, i.e.,

    "Can Mr. Tisdale please direct us to a peer-reviewed paper in a reputable journal in which he has presented his hypothesis and provided supporting evidence of said hypothesis?"

    If Albatross hadn't beaten me to the punch, I would have asked the same question.I suspect that many other readers would have as well.

    The ball, as they say, is in your court, Mr, Tisdale.
  10. I typically don’t bother investigating global data.

    Thereby conveniently avoiding the problem of explaining how net ocean heat content is increasing, along with atmospheric temperature.

    Realistically, that’s the only way anyone can attempt to perform an attribution study on the warming of ocean heat content data--or sea surface temperature data.

    By ignoring ocean heat content?
  11. I'm not sure who is using "curious tactics" here. Albatross's question was straight and simply formulated. In what article has Bob Tisdale subjected his ideas to scientific peer-review? I read Albatross' post and at no point had I the impression that BT was asked to stake his reputation on the DK paper. I don't see how it could even be construed this way, especially by one who claim to be so brilliant that his ideas escaped all of the SkS contributors.

    At any rate, it was a perfectly legitimate question, is there an answer? Tom Curtis also asked an interesting question @45, to which I have not yet seen an answer. IanC raises some interesting points above too. I hope that, for the sake of clarity, all these will be addressed before the conversation drifts to other things.
  12. IanC says: “ENSO is most prominent in the tropics, while for PDO the responses in N. Pacific and Tropics are similar in amplitdue.”

    They are? I believe you’re wrong, IanC. The PDO is standardized. NINO3.4 sea surface temperature anomalies typically are not. The first PC of detrended North Pacific residuals (North Pacific minus global sea surface temperature anomalies) has a standard deviation of approximately 0.18 deg C. In other words, standardization exaggerates the value of the PDO by a factor of 5.5, giving people the impression that it’s similar in magnitude to NINO3.4 sea surface temperature anomalies.

    IanC says: “Zhang et al. 1997, did an EOF with SSTA of the entire basin . For the low-pass filtered (c.f. fig 3) computation, the dominant mode has a similar spatial structure as the one depicted on the JISAO website. Furthermore, the principal component varies similar to the PDO index.”

    All of the analyzed subsets have major variations in response to ENSO giving them similar appearances, but there are subtle differences, so please confirm your last claim with data. Additionally, you’d need to analyze the dataset being discussed, which is the East Pacific, not the North Pacific or the Pacific as a whole. When you examine the data, you’ll discover the East Pacific responds differently than the other portions of the Pacific you’re attempting to compare with it.

    IanC says: “You are technically correct in saying that "PDI index is not SSTA", but you are completely missing the point: the PDI index, in conjunction with the EOF, does in fact describe SST variations.”

    You missed my earlier comment, where I noted that the PDO was inversely related to the North Pacific residuals (North Pacific minus global sea surface temperature anomalies):
    http://i52.tinypic.com/15oz3eo.jpg

    Same thing holds true for the variations in the monthly data:
    http://i52.tinypic.com/1zo8686.jpg

    With respect to Zhang et al 1997 and to Shakun and Shaman 2009, both papers concluded ENSO leads the ENSO-like patterns. In fact the title of Shakun and Shaman is “Tropical origins of North and South Pacific decadal variability.” So why deal in abstract forms of sea surface temperature data like the PDO, IanC? Why not simply compare the East Pacific to a scaled ENSO index and say that the East Pacific has mimicked the NINO3.4 sea surface temperature anomalies over the past 30 years? It’s much easier for people reading this thread to understand:
    http://bobtisdale.files.wordpress.com/2012/09/figure-111.png

    IanC says: “In your original post, you said ‘According to numerous peer-reviewed papers, surface temperatures respond proportionally to El Niño and La Niña events'. I think the reasonable interpretation, based on your wording, is that numerous papers concluded that surface temperatures respond proportionally to El Niño and La Niña events; this is very different from papers assuming the same.”

    In your quote, you forgot the ellipse, IanC, to indicate my sentence continued. In other words, you’ve taken what I wrote out of context. That sentence read in full: “According to numerous peer-reviewed papers, surface temperatures respond proportionally to El Niño and La Niña events, but it’s obvious they do not.” When the entire sentence and the graph linked in that original paragraph…
    http://bobtisdale.files.wordpress.com/2012/09/figure-13.png
    …are included as I has intended, then your interpretation of what I had written doesn’t ring true. Those papers didn’t conclude global temperatures respond proportionally to El Niño and La Niña; they assumed it. In fact, of those papers that I linked for you in my earlier reply, only one acknowledges ENSO residuals. It was Trenberth (2002). In their concluding remarks, they wrote, as I quoted earlier:
    “Although it is possible to use regression to eliminate the linear portion of the global mean temperature signal associated with ENSO, the processes that contribute regionally to the global mean differ considerably, and the linear approach likely leaves an ENSO residual.”

    And as I noted earlier, the divergences in brown…
    http://bobtisdale.files.wordpress.com/2012/09/figure-13.png
    …are those ENSO residuals, which are not accounted for in any of the studies I linked for you.

    Regards
  13. John Hartz: “In your response to Albatross, you conveniently ignore the first question hea had posed, i.e…”

    John, I’m not sure why you’re belaboring the point. You and Albatross know quite well that they have not appeared in a peer-reviewed journal. All I do is present data, and it contradicts the hypothesis of anthropogenic global warming. Now it's my turn to ask you and Albatross a question: how would my findings make it past the gatekeepers of AGW peer review?
  14. @Bob Tisdale #63:

    Actaully, I know very little about you and your analyses. The fact that you have not published anything in a mansitream peer-reviewed journal explains why. Either you are confident about the validity of your work, or you are not.
  15. doug_bostrom says: “Thereby conveniently avoiding the problem of explaining how net ocean heat content is increasing, along with atmospheric temperature.”

    Not sure how you could conclude that from what I had written, doug. I wrote and you quoted part of, “I typically don’t bother investigating global data. Why? Looking at global data can be misleading. It’s best to divide the oceans into logical subsets, because coupled ocean-atmospherics processes impact ocean basins in significantly different ways.”

    doug_bostrom says: “By ignoring ocean heat content?”

    Where in the sentence that you quoted (Realistically, that’s the only way anyone can attempt to perform an attribution study on the warming of ocean heat content data--or sea surface temperature data.) does it say that I ignore ocean heat content, doug?

    An example for you, doug, of how I address data in logical subsets: Here’s an annotated graph of the Ocean Heat Content of the North Pacific north of 20N (the same area that’s used for the PDO).
    http://i48.tinypic.com/2l9gqxf.jpg

    Now it’s time for me to ask you questions, doug. How does the AGW hypothesis explain the cooling of the North Pacific (north of 20N) from 1955 to the late 1980s? And how does it explain the sharp rise over a two year period? And how does it explain that the North Pacific north of 20N would have cooled over the entire term of the data if it wasn’t for that 2-year rise?
  16. Philippe Chantreau says; “I read Albatross' post and at no point had I the impression that BT was asked to stake his reputation on the DK paper. I don't see how it could even be construed this way, especially by one who claim to be so brilliant that his ideas escaped all of the SkS contributors.”

    Here’s what Albatross wrote, Phillipe:
    “Additinally, would Mr. Tisdale stake his ‘reputation’ (in the 'skeptic' blogosphere) and his hypothesis on the aforementioned paper? He can respond to the last statement and question onthe relevant DK thread.”

    He quite clearly stated in his question, “would Mr. Tisdale stake his ‘reputation’ (in the 'skeptic' blogosphere) and his hypothesis on the aforementioned paper?”
  17. Philippe Chantreau says “Tom Curtis also asked an interesting question @45, to which I have not yet seen an answer.”

    Sorry I missed his question.

    Tom Curtis asked, “Thankyou. I notice that the strongest correlation between Nino 3.4 and global SST is when global SST lag Nino 3.4 by nine weeks. In your comparison, you say you used a 6 month (equivalent to a 26 week) lag. Why did you use a lag 17 weeks longer than that indicated by the data?”

    Please advise where you’re noting that the strongest correlation between NINO3.4 and global SST is when global SST lag NINO3.4 by 9 weeks. Also, in my comparison, assumedly this one…
    http://bobtisdale.files.wordpress.com/2012/09/figure-13.png
    …it’s not a global dataset. It excludes the East Pacific Ocean where the direct effects of ENSO would be felt. Also note how well the scaled NINO3.4 data and the Rest of the World data align during the evolution of the 1997/98 El Niño. The 6-month lag works quite well.
  18. IanC @57,

    I'm sorry, but it appears we're not looking at the same dataset here. Please examine one more time the second and third figure in my Part 1 post and then the animation at the end. Then read once more what I point to. What exactly are we looking for? "[...] places where the global curve diverge permanently from the NINO curve. There are only (and by that I mean ONLY) two cases between 1981 and 2012 where the extra heat piled up globally after an El Niño and during the transition to the first following La Niña is never fully made up for before the ENSO pendulum turns and the heat comes in again, both in the NINO3.4 region and globally." If you observe the second figure (Level 1), how can you miss these two instances? Only in 1987-88 and in 1998-99 does the global curve lift its mean SSTA level up from the NINO3.4 curve and stay there. Nothing of consequence happens at any other time between the two curves. You must not forget that in this exercise we're always relating the global curve to the NINO3.4. In Part 2 I also show you WHERE the two specific upward shifts originate - check out the second figure in my Part 2 post.

    You say it's a noisy dataset. I've shown you just how 'un-noisy' it really is. If one simply cares to take a closer look at the data. The global curve pretty much consists of two component signals: 1) the regular large-scale NINO ups and downs and 2) the two sudden and significant hikes in mean temperature level as compared to the NINO3.4 after the El Niños of 1986/87/88 and 1997/98 respectively.

    Sphaerica is only obfuscating and confusing the matter. He/she isn't reading what I'm writing. He/she isn't looking at my plots.

    Let's have a look at his/her graph. (Compare with my second figure in Part 1.) The first chosen La Niña is an extended, yet fairly weak event, fluctuating in and out of La Niña territory. There is absolutely no 'extra' global heat accumulating here. No need whatsoever for a downward adjustment. Then he/she skips the next La Niña (88/89) altogether, which as it happens was the deepest ENSO event since the 70s. Peculiar, don't you think? Here you DO clearly see the extra global heat accumulating, inducing an upward shift in mean SSTA level globally relative to NINO3.4. Sphaerica's next blue line is not a La Niña at all. It's Pinatubo. Then he/she places the next line right smack in the middle of the La Niña 98/99/00/01, but of course by doing so again misses the actual instance of global accumulation of heat, which quite evidently occured during the first La Niña-year after the 1997/98 El Niño (98/99). Sphaerica's last La Niña adjustment is again performed at a place along the curve where absolutely no downward adjustment is called for. He/she's completely missed what we're actually looking for.

    I'm telling you again (and I thought this was already made very clear in my two posts, I feel a bit silly having to repeat it), there is no extra global trend, no increasing divergence between NINO3.4 and global SSTA levels anywhere outside the two obvious upward shifts. (Referring once more to the second and third figure in my Part 1 and the animation towards the end.)

    You see, this isn't about playing around with statistical trickery. About who can produce the 'best' fit. It's about what the actual data at hand is showing us, telling us. What's in the data? That's all I've done so far. Explored the data. It's all right there. Right there in front of you. In the data. Something out of the ordinary is very clearly happening globally (outside the East Pacific) during the transition from specific, solitary and powerful El Niños to the deep La Niñas directly on their heels.

    This is all about natural processes. Readily observed to unfold. They happen. I still haven't gotten to those, though. That's for Part 3.

    The satellite-based Reynolds OI.v2 is a benchmark dataset for SSTs since 1981/82, globally comprehensive, a tried-and-true source of high-resolution data. It agrees well with surface-based datasets like the HadSST, HadISST and ERSST. To quote William M. Briggs: "We do not have to model what we can see. No statistical test is needed to say whether the data has changed. We can just look."

    Why not let the data speak for itself?
  19. Bob,

    I explained very carefully in my previous post how one should relate the PD) index to SST anomalies (relative to global temperature, or residuals if you prefer)
    (1) Do you agree that one cannot interpret the PDO index in terms of SST anomaly without the corresponding EOF?
    (2) Do you agree with my example, that -0.2 degrees C per standard deviation is a reasonable average for the EOF over N Pacific (NP)?
    (3) Do you agree that with (2), it explains why your observation that (a) PDO varies inversely with NP SSTA and (b) the PDO index "exaggerates" the fluctuation in NP SSTA?

    Regarding Zhang et al 1997:
    Here's their figure 3



    HP: the EOF and PC shows that this is the usual ENSO mode. You can check the PC and it follows ENSO indices quite well. The spatial EOF also shows good agreement with ENSO: the hot spot on the east corresponds to 0.7 degrees per SD, the response in NW pacific is much weaker: -0.2 degrees per SD.

    LP: This is the PDO mode:comparing the PC (bottom) to the PDO index(top):

    You can see they agree reasonably well.

    Looking at the EOF, you can see that the response in the NW pacific (-0.3 degrees per SD) is comparable to the responds in the eastern pacific (0.4 degrees per SD).

    Your comment " Additionally, you’d need to analyze the dataset being discussed, which is the East Pacific, not the North Pacific or the Pacific as a whole." is puzzling.
    One of the central question here is whether PDO is a basin wide phenomena, and thus can account for the lack of warming on the eastern pacific. Can you elaborate on why using data from the entire pacific to determine the existence of a basin wide mode is inappropriate.

    ##########################################
    You said " Why not simply compare the East Pacific to a scaled ENSO index and say that the East Pacific has mimicked the NINO3.4 sea surface temperature anomalies over the past 30 years? It’s much easier for people reading this thread to understand"

    What that will accomplish exactly? NINO3.4 is part of the east Pacific so the fact that they vary similarly should not come to a surprise. How does that say anything about the long term decadal trend of the east pacific?

    #############################################
    In your original post, the following quote appeared:
    “According to numerous peer-reviewed papers, surface temperatures respond proportionally to El Niño and La Niña events, but it’s obvious they do not.”

    The last sentence is largely irrelevant because it is clear that you are disputing something. The question is what are you disputing? My point is from what you've written you are disputing conclusions of papers (which is surprising so I asked for references), whereas in reality you are disputing the assumptions.
  20. Sorry Bob, but I've got a hanging question open here that you've not answered and which needs to be addressed if your hypothesis is to have any relevance to global warming. It is after all global warming that is the topic of this site; forgetting the rest of the globe and focusing on the E. Pacific is only a variation of the infamous "escalator." So I'm not really interested in the wee specifics of the E. Pacific, I'm more interested in the relevance of your hypothesis to the topic of this web site, global warming.

    It's a fairly simple question.

    Where is the energy required to produce net warming of the entire global ocean along with the atmosphere coming from? Put another way, are you claiming that the energy required to produce net warming of the global ocean and atmosphere is coming from the global ocean itself?

    Please don't answer by reference to the E. Pacific; the E. Pacific is after all a relatively small part of the global ocean and thus contains only a relatively small component of the net ocean heat content.
  21. Bob, I'm still working through your analysis, but I have to say: the 'gatekeepers of the science' claim is pretty pathetic. Surely you don't buy into that garbage.

    If someone held your hand to the fire and forced you to attempt publication, what would your hypothesis or (better yet) research question be? That's something I'm still not clear on. I'm also not clear on the physical mechanism you're proposing (if indeed you are). How does a step change fit into Walker circulation dynamics, what is the trigger mechanism, etc.? And does the results of Tokinaga et al. (2012) change the way you look at the trends and relations?

    Kayell, data, in this case, are the result of a set of dynamically integrated physical processes. Untangling those physical processes is the only way to understand the data in a meaningful way. See David Rose, for example, who makes a colossally dumb statement to the public at large based on a simplistic reading of a data set that itself is limited in a variety of ways in terms of representation.

    I can buy a step change if I see a physical mechanism. If it's there, it's there. What I fear, though, is that you're trying to argue for a step change not in order to advance the science but in order to present a specific message to the public at large, a message that may or may not be supported by investigations into the physical processes at work.
  22. Bob Tisdale.

    Further to Doug Bostrom's latest asking of the matter concerning from where the internal heat comes to persistently warm the planet over decades, I'm also curious about where you think the heat being trapped by the anthropogenic component of atmospheric CO2 is ending up, and why it isn't warming the planet.

    Numbers and references are welcome.
  23. Bob Tisdale @67, thankyou for answering my question.

    I am unsure why you draw attention to the fact that you used East Pacific vs the rest of the world in your figure. There is even less correlation between the East Pacific and the rest of the world than there is between Nino 3.4 and the globe, or Nino 3.4 and the rest of the world (ie, gobal minus East Pacific). Indeed, Nino 3.4 vs the rest of the world even gives the best correlation with much greater lag than does any other comparison I have made, with a correlation of 0.076 at thirty one weeks lag. All other comparisons other than Nino 3.4 vs Global show the highest correlation with zero lag, and as previously indicated Nino 3.4 vs Global shows its best correlation (0.382) at nine weeks lag. Here is the data:



    "Indian Ocean" refers to a band between 5 degrees North and 5 degrees South in the Indian Ocean having the same area as Nino 3.4, and as you can see correlates better both with the globe minus the East Pacific, and the globe than does Nino 3.4

    Given this data, your response that you lagged the rest of the world vs East Pacific data is an evasion rather than an answer. Doing so provides less justification for the lag you have chosen, not more. This leaves you in the position where your only justification of the lag that you have chosen is that it helps you make your point. That is, you have a rhetorical, not a scientific justification for your chosen manipulation of the data.

    As an aside, I was considering the first of your graphs reproduced by Kayell here, which I now realize is not lagged (final clause added in edit). Correctly lagged it looks like this:


    (Both detrended)

    What also becomes clear using the proper lag is that the way in which global temperatures track ENSO events is noisy. Focusing on just one or two such events will simply focus on noise in the system. It is, in other words, simply cherry picking.

    (Edited to delete faulty analysis, TC)
  24. Kayell,

    So, here is your "detrending", based on presumed El Niños (although since such events last a year or more, it's still a little vague as to where Tisdale actually made his breaks, or why the breaks would be at specific points in time):



    Here is mine, pretty much randomly using spots in various La Niñas (no, there's no real, objective justification for my selection of points, any more than there is for yours):



    And here is the data detrended properly, over time, using a linear coefficient (courtesy of Tom Curtis):



    Personally, I think the proper statistical method gives the best fit, my tongue-in-cheek La Niña method the second best fit, and Tisdale's magical El Niño Gremlins method the worst fit.

    But, all in all, I think anyone would agree that there's not really any strong reason to argue that one is notably better than the other.

    So why wouldn't a simple, linear and correct detrending apply (Occam's Razor)?

    Why are we wasting any time at all on this discussion?
  25. I really like the idea of gatekeepers for science, I don't think it's a bad thing. Without gatekeepers, soon you get fruicakes publishing stuff about how the Earth has been expanding over the past 5000 years and yet even more fruitcakes touting the piece around saying "see, it's published science."

    A gatekeeping process is necessary. Sorry for the OT, end of sopabox moment. I guess the conclusion is that Bob Tisdale's work has not even been proposed for publication? I'll interpret his response as such unless told otherwise.
  26. Sphaerica @74, the graph you have shown is the lagged global SST. A more direct comparison is without the lag:



    The differences between that graph and the first in your post are that I have used weekly rather than monthly data, and that I have rescaled by the ration of the Standard Deviations of the Data, ie, by multiplying the Nino 3.4 anomaly by 0.1224305012. Had I scaled the global SST to match Nino 3.4 as done in the first graph, the factor would have been 8.1678992563 rather than 10. In other words, that graph inflates the Global SST anomaly values by 22%. I also detrended the Nino 3.4 anomaly, and it is not clear that Tisdale has done so in the first graph. I hope that helps.
  27. Philippe Chantreau - Agreed. Gatekeepers keep down such nonsense as an "iron core sun", odd planetary alignments driving Earth climate, little green men, and so on.

    Peer review checks for basic, credible evidence. I haven't seen any for the ENSO/global warming hypothesis, and I rather doubt such nonsense would make it into a peer-reviewed journal of any relevance or note.
  28. Bob Tisdale - ENSO cycles are (as shown in several posts above) a quite good match for detrended global SST's. Which indicates that that ENSO is not responsible for the trend itself.
  29. As anyone who remembers the big hair and shoulder pads of the 80s knows, Gatekeepers are complemented by Key Masters. Bob Tisdale seems to be approaching science with a rusty nail rather than anything resembling a key.

    Why am I reminded of the Stay Puft Marshmallow Man?
  30. I think this is one of the most interesting graphs of Reynolds SST data for this discussion:



    It is simply the weekly SST anomaly for various regions of interest to this discussion. It is presented without rescaling, rebaselining, or lagging or any other device that might conceal the vast differences of variability between the two regions. So presented it is immediately apparent just how variable the Nino 3.4 region is compared to other regions.

    You might think that that is just because it is a small area, and the larger areas contain sub-regions with contrasting trends that reduce the mean variability. However, one of those regions, (Indian Ocean Tropical, in orange) is the region of the Indian Ocean from 50 to 100 degrees East, and from 5 degrees North to 5 degrees South. That is, it occupies the same area, and the same latitude as the Nino 3.4 region, yet it has only 32.3% of the variability of the Nino 3.4 region. Clearly the Nino 3.4 region (and presumably other directly ENSO effected regions) are exceptionally variable relative to other regions of the world's oceans.

    Another way of saying that is that the region has a very high noise to signal ratio when it comes to detecting medium term trends. The same is true of the East Pacific, which is dominated by ENSO variations.

    We all know that when it comes to detecting long term trends, we want to focus on the signal, not the noise. If you do not, you will find yourself "going down the up escalator, and all sorts of other improbable contortions. That is not reason to avoid studying the Eastern Pacific SST, but it is reason to take care that you are not fooling yourself with noise to avoid looking at the signal.

    You can take several steps to avoid fooling yourself in that regard. You can check out statistical significance:



    This is a bit crude, but as the table shows, the increase in regional temperatures plus two standard deviations for Nino3.4 (1.52 C)and the East Pacific (0.4 C) comfortably exceeds the increase in Global SST anomaly (0.26 C). A proper analysis of the error of trend calculations taking into account auto-correlation and multi-decadal influences such as the PDO is likely to find (I suspect) that they do not differ significantly from the model predictions for the East Pacific of 0.42 and 0.44 C (as quoted by Tisdale).

    Be that as it may, the important point here is that Tisdale's hypothesis does not even pass the most rudimentary test in showing that the limited warming in the East Pacific is unexpected given global warming.

    An even more rudimentary test is to check that your analysis is robust with regard to endpoints, and hence is not just a function of short term fluctuations. In this case, we that ENSO dominates the region and is the source of the large fluctuations in temperature. Looking at the ENSO 3.4 index, we see that Tisdale's start point just happens to precede the second strongest El Nino event since 1950, and precedes a period note worthy for its lack of La Ninas; but that the end of the period is noteworthy for weak El Ninos and several strong La Ninas:



    This pattern fully accounts for the negative trend in the Nino 3.4 anomaly, and hence the flat trend for the Eastern Pacific. Is it, however, a consequence of the start point of the data?



    As it turns out, yes it is. Just preceding the start point was another period of strong La Ninas. Including that period in the data results in a warming East Pacific:



    It turns out that not only is the lack of warming in the East Pacific not statistically significant, its existence is an artifact of the choice of start and endpoints in the data.

    I assume this is not the result of conscious cherry picking. Tisdale's chosen data set just happens to start in 1981. But he should have been aware of the possibility that what he thought he saw was just an artifact of incomplete data, and checked longer time periods using other data. He was negligent at least.

    This leaves him in an awkward position. Tisdale has provided no physical basis for his theory. He is, therefore, recommending it to us soley on the basis of the statistically unusual nature of the data. But it turns out that the data is not statistically unusual after all. That leaves his theory with nothing to recommend it until he can provide us with a physical mechanism behind his theory.
  31. Sure, KR & Phillipe, but I strongly suspect that that type of gatekeeping is not what Bob is imagining, although I can't think of any examples that would supply evidence for such a thing -- unless one chooses to defend various methodologies attempted by Soon & Baliunas, Spencer & Braswell, or Watts et (a diminishing) al.
  32. Just swooping down to clarify a few things for Mr. Tisdale. To be accurate one should refer to the theory of anthropogenic warming or theory of human-induced warming, it is not correct to speak of the "hypothesis of anthropogenic warming". To illustrate using an example: Mr. Tisdale has a hypothesis, just like the Slayers of the Skydragon have (had?) a hypothesis. Now until Mr. Tisdale succeeds in convincing the scientists who specialize in this area that his ideas have merit, his idea will forever be destined to obscurity and be nothing more than a hypothesis on a climate "skeptic" or climate denier blog.

    As for his disappointing excuse not to pursue publishing his ideas in a journal, there is always "Principe Scientfic Intl.". But doing so would not meet the criterion for publishing in a reputable scientific journal. I would dare Mr. Tisdale to publish in J. Climate or JGR-A or GRL or Nature or Science, but then I would be guilty of very likely wasting the valuable time of the editors and busy scientists with Mr. Tisdale's well-intentioned, but misguided ideas. Anyhow, it is telling that he is not up for the challenge, instead invoking conspiracy theories rather than actually submitting a manuscript for review by experts in the field.

    On the following, I do not necessarily wholly disagree with Mr. Tisdale, however, scientists have been researching this and publishing their findings in highly respected journals for some time now:

    "It’s best to divide the oceans into logical subsets, because coupled ocean-atmospherics processes impact ocean basins in significantly different ways. Realistically, that’s the only way anyone can attempt to perform an attribution study on the warming of ocean heat content data--or sea surface temperature data."

    Here is a review of some relevant papers through time on this subject. Note that they all find compelling evidence that the long-term warming of the planet's oceans is primarily externally driven (that is it is primarily the result of higher greenhouse gas levels from human activities). They have found this using sea-surface temperatures, ocean heat content and even salinity. Moreover, they have found the anthropogenic signal both globally and over individual basins. In short, the long-term warming of the planet's oceans is primarily in response to rising greenhouse gas concentrations, not El Nino or ENSO.

    To wit:

    Sedláček and Knutti (2012,GRL). Two of their key findings:
    "Ocean warming of the last century cannot be explained by natural variability
    The warming signal is visible throughout the whole ocean"


    Gleckler et al. (2012, Nature Climate Change),
    "Our detection and attribution analysis systematically examines the sensitivity of results to a variety of model and data-processing choices. When global mean changes are included, we consistently obtain a positive identification (at the 1% significance level) of an anthropogenic fingerprint in observed upper-ocean temperature changes, thereby substantially strengthening existing detection and attribution evidence."

    From Pierce et al. (2012),
    "We find that observed changes are inconsistent with the effects of natural climate variability, either internal to the climate system (such as El Niño and the Pacific Decadal Oscillation) or external (solar fluctuations and volcanic eruptions). However, the observed changes are consistent with the changes expected due to human forcing of the climate system."

    From Santer et al. (2008, PNAS),
    "For the period 1906–2005, we find an 84% chance that external forcing explains at least 67% of observed SST increases in the two tropical cyclogenesis regions. "

    From
    Pierce et al. (2006, J. Climate)
    ,
    "The observed sampling of ocean temperature is highly variable in space and time, but sufficient to detect the anthropogenic warming signal in all basins, at least in the surface layers, by the 1980s."

    From Barnett (2005, Science)
    "A warming signal has penetrated into the world's oceans over the past 40 years. The signal is complex, with a vertical structure that varies widely by ocean; it cannot be explained by natural internal climate variability or solar and volcanic forcing, but is well simulated by two anthropogenically forced climate models. We conclude that it is of human origin, a conclusion robust to observational sampling and model differences. "

    From Barnett et al. (2001, Science)
    "Further, the chances of either the anthropogenic or observed signals being produced by the PCM as a result of natural, internal forcing alone are less than 5%. This suggests that the observed ocean heat-content changes are consistent with those expected from anthropogenic forcing, which broadens the basis for claims that an anthropogenic signal has been detected in the global climate system."

    Then again, I do not expect Mr. Tisdale to be swayed by the overwhelming evidence against his idea. But maybe he will surprise us.

    Now the roaring forties beckon.
  33. Albatross - Thank you, a very informative post.

    The timings, patterns, and energies observed (in all ocean basins) point to the theory of anthropogenic warming, and contradict the hypothesis of natural variations and cycles. If Bob Tisdale wishes to argue his hypothesis he's going to have to show that his hypothesis matches all of those observations, and in addition provide a supportable mechanism.

    In particular, he's going to have to address these existing works, demonstrate that they have errors, and how his hypothesis gives a better explanation for observations (not to mention showing why the expected GHG warming does not occur in his framework). You simply cannot put up a new hypothesis without demonstrating shortcomings in the existing theories - not if you want to be taken seriously.

    As with Albatross, I don't expect Tisdale to be swayed by the evidence either; he has a great deal invested in his hypothesis. But I'm willing to be surprised.
  34. Tom Curtis @73 says:

    "As an aside, I was considering the first of your graphs reproduced by Kayell here, which I now realize is not lagged (final clause added in edit). Correctly lagged it looks like this: "

    Please don't misrepresent the graph you're showing as equal to mine, only lagged. Your global graph is not based on my global, adjusted down in 1987-88 and 1998-99 only. Your graph is based on Sphaerica's randomly adjusted one. This is quite easy to see.

    The justification for MY two points of adjustment is self-explanatory; just look at (compare) the original data. The justification for Sphaerica's adjustments is nonexistent.
  35. Kayell,

    You clearly fail to understand. Tom's graph is not based on either of our methods. It is properly detrended using a linear term.

    The justification for your two points is no better or worse than mine. It is arbitrary, unless you can submit an objective mathematical formula that was used to derive your points, as well as a valid physical justification (i.e. a mechanism whereby El Niño heats the atmosphere in step-changes in only those two instances) for doing so, both of which are lacking in your discussion.

    Tom's method, on the other hand, simply assumes a generally linear warming (not perfectly accurate, no, but it's the right way to do things when it is not entirely possible to separate the noise from the signal).

    Tom's method is the way it should be done, it makes no assumptions without physical cause, is entirely objective, and produces a result superior to yours/Tisdale's.

    So why, then, would we consider your/Tisdale's theory as anything more than playing games with graphs?
  36. Kayell @84, I apologize for inadvertently misrepresenting your technique; although it feels strange to apologize for assuming somebody has used a valid rather than an arbitrary rescaling. Having reread your post @35 (which I had previously only skimmed, I now see where you wrote:

    "When I 'detrended' the global SSTA curve in the graph above, I didn't use a statistical tool to remove a general upward trend. All I did was to pull it down at two (2) short sections: two datapoints in the last half of 1987 (July and November) and one datapoint in the beginning of 1999 (January)."


    Would you please inform me the magnitude of the downward ajustment for each of the three months?
  37. Kayell,

    Your quote of William Briggs came from his post here, but I don't think he meant it the way you used it. Considering what he said in the rest of his post, I think his point is that if you are claiming that the trend is upwards, you don't have to use a linear model to make that claim. Whether the claim is a valid one is an entirely different matter.

    I don't fully agree with what he said, but the example he used is an excellent example as why one has to be very careful drawing patterns out of a noisy time series (BTW ENSO is noise when you are looking at multi-decadal trends). He artificially generated an artificial time series with zero trend with random noise:

    Yet if you fit a trend line it yields a statistically significant result.

    Now my question to you is, if you just eyeball the graph and claim that there is an increase till 2005 and then decrease from there, is it a valid claim?

    If you claim that there is a step, you at the bare minimum have to run some statistical testing as a sanity check. If your assertion passes a statistical test, we can then proceed with caution. If does not, there is no reason for it to be taken seriously.

    ############################

    Now that I think about it a bit more, I think there is a much bigger problem.

    Your basis for shifting the global SSTA at those two points is based on your arguement that "extra heat piled up globally after an El Niño and during the transition to the first following La Niña", which you supported with the animation, that supposedly shows the "extra heat globally".

    The problem is this: since you are plotting a scaled global temperature anomalies and a regional temperature anomalies, you can't even interpret the difference between the two as a temperature difference because one of the quantities is scaled, let alone extra heat.
  38. You have to love Bob Tisdale complaining about the 'gatekeepers' of science ... in response to an opening post that starts by discussing the failings of McLean et al who published in JGR!! Bob, are you saying that your science is not even up to the standard of McLean et al, a classic example of science being entirely open to the so-called skeptics?

    And for the umpteenth time, where is the heat coming from? And why do you persist in selecting favoured subsets of the data, rather than consider the full body of data? Your cherry-picks may be more elegant than the "it's not warmed since 1998" crowd, but they are still cherry-picks.
  39. To all who have commented in response to my appearance here at SkepticalScience: You’ve not answered my very basic questions.

    In my opening comment (40) here, I presented some graphs and asked questions of you. The first graph was for the East Pacific, which shows no warming over the past 30 years.
    http://bobtisdale.files.wordpress.com/2012/09/figure-111.png
    I asked, Why hasn’t the East Pacific warmed? IanC has attempted to explain why it has not warmed using an abstract form of sea surface temperature. He’s making the effort. Bravo, for that.

    The third graph was the detrended sea surface temperature anomalies for the Atlantic, Indian, and West Pacific, which I referred to as the “Rest of the World.”
    http://bobtisdale.files.wordpress.com/2012/09/figure-13.png
    It shows four periods when the Rest-of-the-World data diverges from the ENSO index (the scaled NINO3.4 sea surface temperatures [scaling factor 0.12 and lag 6 months). The two divergences in green are obviously the effects of El Chichon and Mount Pinatubo, but the divergences in brown are ENSO-related. The sea surface temperatures for the Rest of the World do not cool proportionally during the La Niña events of 1988/89 and 1998-2001. Everyone here has avoided the discussion of that graph. That’s the big ticket item, and it’s blatantly obvious why it’s important.

    Up through comment 67, I have replied to your questions and comments, yet no one here has replied to that question from comment 40. It’s time for you to catch up with me. You all are running way behind in the QnA.

    So I’ll ask the question again: Why does the detrended [Rest of the World] data diverge from the ENSO index during the 1988/89 and 1998/99/00/01 La Niñas?

    The ball is in YOUR court.

    Unless YOU can explain those divergences, there is no reason to continue this conversation. If and when you explain them, I’ll be happy to respond to all of the questions you’ve presented.

    I’ll check back every couple of days.

    Regards

    PS: skywatcher says: “You have to love Bob Tisdale complaining about the 'gatekeepers' of science…”

    I wasn’t complaining, skywatcher. I was being realistic. There is a difference.
  40. Bob Tisdale:

    Why should anyone here feel obliged to respond to your nonsense?

    As far as I can see your questions are an attempt to side-step sea surface temperature trends as well as increasing ocean heat content.

    I mean, come on. Your graph of "Detrended Rest-of-World SST Data Disagrees with The Warming of SST Anomalies As Portrayed By AGW Proponents" [SST abbreviated by me]? Of course it disagrees - you detrended the SST data.

    As far as divergence between SST behaviour and ENSO goes, one would only expect complete agreement between SSTs and ENSO if ENSO were the sole driver of SSTs. But the fact that there is an upward trend in SSTs puts the boots to such a belief: other factors also drive SST behaviour. So, if anything, we would expect divergence from ENSO from time to time.

    Tom Curtis' post at #80, in the meantime, puts the boots to your claim that the East Pacific "hasn't warmed":


    It turns out that not only is the lack of warming in the East Pacific not statistically significant, its existence is an artifact of the choice of start and endpoints in the data. [Emphasis original.]


    So how is one to characterize your claim "no one here has replied to that question from comment 40" except as refusal, whether through inability or unwillingness, to read others' posts on this thread?
  41. Bob says he's answered all questions put to him here. That's actually not true. He's been asked twice by a couple of different people to explain a key feature of his argument and so far has not replied.

    46

    3: (perhaps most importantly) what is the energy source that allows the oceans to drive atmospheric temperature changes while themselves warming on a global scale? Where is the energy coming from, Bob?

    70

    Where is the energy required to produce net warming of the entire global ocean along with the atmosphere coming from?


    Bob, please just show us how a mass (global ocean+air) can increase in temperature without energy being added to it.

    Or from another perspective having to do with what our instruments tell us: Is global warming real or not?
  42. Bob,

    We didn't even get anywhere with the first question, why move on to the second? Doing so will just make the discussion intractable when we haven't even finished the first point.

    Let's recap:
    You @40: Why hasn't east pacific warmed?
    Me @41: Perhaps its internal variability such as PDO
    You @ 42: PDO can't be because the index exaggerates variability and the is inversely related to the N. pacific residual, and the dominant component is the N pacific
    Me @ 48: Here's evidence that PDO is a basin-wide mode, and the response in the east is the right order of magnitude to explain the lack of trend.
    You @ 52: No it can't be basin wide. PDO index doesn't represent SSTA because it is inversely related to the N. pacific residual.
    Me @56: Shows more evidence of PDO being a basin wide mode, shows PDO index can represent SSTA when interpreted in conjunction with the EOF, I even showed how you can get the scaling factor you found, and why PDO index is inversely related to N pacific SSTA.
    You @62: PDO index is standardized and exaggerates variability. PDO is inversely related to North pacific SSTA. PDO is index is abstract, why not use NINO3.4?

    Up to this point, all three of your counters consist of repeating what you think is right. You have not cited any evidence that your understanding is correct. You have not cited one single journal article that PDO does not impart an inter-decadal variability in the east Pacific.

    Whether PDO index is abstract is irrelevant, and frankly your complaints about the index are just red-herrings. You have avoided the real question: is there an inter-decadal variability that can explain the lack of warming in the east?

    To me you are just avoiding the issue, and it is not even clear if you've spent time reading and thinking about what I said, because if you had, you will not be repeating the same set of arguments three times.

    Look, it is not hard.

    If you think I have a point, that PDO is a viable answer to your first question, say you'll have to think about it and then we move on to your second question.

    If you think I'm wrong, explain, with new evidence, why I am wrong, and PDO is not a plausible explanation for the trend in E. pacific.

    Don't use a lack of discussion on your second question as an excuse to avoid discussing responses to your first question.

    BTW, I think you lost track of where the ball is.

    You served, I returned serve. I have yet to see the ball coming back to my side of the court. All there is so far is complaints that the ball is too fuzzy, too hard, and there's no ball.
  43. A quick question for Bob Tisdale to clarify something about the nino/nina thing: are you arguing that SSTs respond more strongly to El Nino than to La Nina, i.e. that El Nino warms SSTs more than La Nina cools them?
  44. And, as Bob himself remarked earlier, we don't want to take anybody's words out of context. Skywatcher's full sentence about the complaining on "gatekeepers of science" was as follows:

    "You have to love Bob Tisdale complaining about the 'gatekeepers' of science ... in response to an opening post that starts by discussing the failings of McLean et al who published in JGR!!"

    JGR being a serious journal, the kind that would definitely add some weight to Bob's argument if he submitted his work there and passed peer-review. Nonetheless, even if that happened, it would be met with healthy, scientific skepticism, as this is what's it's all about, after all; we all understand that peer-review is a minimum standard, not a golden one, and it is not infaillible.
  45. Following Kayell's complaint (@84), I have reproduced his "detrending" method using the weekly OHC data:



    For those wanting technical details, I adjusted each interval between Kayell's stated adjustment points to have a common mean. Transitions where spaced over five weeks with an equal change in each week to avoid introducing very large adjustments in a single week. Both the Nino3.4 and Global anomalies have been divided by their Standard Deviation. The rescaling makes the magnitude of variation consistent for comparison without pretending global fluctuations are much larger in degrees C than they actually are.

    Contrary to Sphaerica @74, although this method of detrending is arbitrary, it does not give a noticeably inferior fit to simple linear detrending:


    (Note, this graph is essentially the same as that in my post 76, except that it uses Standard Deviations rather than degrees C for the y-axis.)


    Indeed, if you look at the residuals - the difference between the scaled Nino 3.4 anomaly and the scaled Global anomaly in the two graphs, it is difficult to tell them apart:



    Of particular interest here is the yellow line, which shows the difference in the residuals between the linearly detrended and Kayell adjusted graphs. It shows a clear pattern of rising gradually with the linear detrending, with three abrupt shifts down from the adjustments following Kayell's method. The important thing to note is that the difference never exceeds (approximately) 0.5 Standard Deviations. That means the difference between the two methods is not statistically significant.

    That simple fact is devastating to Kayell's argument.

    Kayell (and Tisdale) argue that the data show step changes in the SST data, yet it is well known that the combination of a linear trend, noise and natural cycles can give the appearance of step changes where none exist:



    Consequently, when we see what may naively be interpreted as a step change, we need evidence that we are not simply fooling ourselves. That evidence, for Kayell (and Tisdale) is the ability to "detrend" the global SST anomaly by introducing three major shifts rather than by simply linear detrending. But as it turns out, there is not statistical difference between the two methods. Therefore, the ability to "detrend" by introducing step changes is not significant evidence.

    Indeed, it is worse than that. We can test the "fit" between the Nino3.4 and Global anomalies for the two different methods of "detrending". We can take the correlation, for example, although there are reasons to think it is not a suitable method for the comparison. Alternatively, we can take the Root Mean Squared Deviation:



    That's all the difference there is between the two methods of "detrending". The linear detrend scores (just) better in terms of Root Mean Square Deviation, but the Kayell Adjustment shows a whopping 0.0075 better correlation between Nino 3.4 and adjusted Global SST anomalies. And on that massive 0.0075 difference rests the entire claim of a step change in sea surface temperatures following the 97/98 El Nino.

    Colour me unimpressed.

    Of course, this is not a case where we are comparing the predictions of two physical theories with distinct predictions. Climate science clearly predicts an approximately linear trend in SST over the period of interest, as modulated by ocean cycles and noise. There is a substantial, well worked out physical theory predicting the result. What is more, there are known factors likely to lead to the appearance of a step change in the data. The Pinatubo eruption in the 1990s, and a weakening solar cycle coupled with a switch from El Ninos to La Ninas in the 2000s are, when coupled with global warming, perfectly adequate explanations for that appearance.

    In stark contrast, neither Kayell nor Tisdale have provided any physical theory predicting a step change. Consequently their only justification for believing one exists is statistical, ie, the 0.0075 point superior correlation when using the Kayell Adjustment compared to a linear detrending. So once again we find that Kayell and Tisdale have no evidence to support their claims, and no theory to justify making them.
  46. @ Bob Tisdale:

    Do you agree, or disagree with the following statement?

    “Naturally occurring climate variability due to phenomena such as El Niño and La Niña impact on temperatures and precipitation on a seasonal to annual scale. But they do not alter the underlying long-term trend of rising temperatures due to climate change as a result of human activities,” said WMO Secretary-General Michel Jarraud.

    Source:2012: Record Arctic Sea Ice Melt, Multiple Extremes and High Temperatures, WMO Press Release No 966, Nov 28, 2012
  47. A quick question for Bob Tisdale to clarify something about the nino/nina thing: are you arguing that SSTs respond more strongly to El Nino than to La Nina, i.e. that El Nino warms SSTs more than La Nina cools them?


    It's obvious Philippe - ENSO is a bootstrap process, a magic ratchet or a magic pudding as I've noted elsewhere.

    However, I very much doubt that Tisdale will actually ever elucidate the thermodynamics of his claim. He's been asked here repeatedly, and many others of us have pressed him about it on multiple occasions over a year ago at WWWT, and there's never been a simple, straight explanation - or even a convoluted one for that matter.

    Having said that, I'd be most curious to hear Tisdale's response to your question.
    Response: [DB] Closed the italic hashtag; guessed as to its most likely location.
  48. 'I wasn’t complaining, skywatcher. I was being realistic. There is a difference."

    I agree that Bob is being realistic - the review process would make demands that I think Bob is unable to answer.
  49. I believe that the following graphic relates directly to our ongoing discussion with Tisdale.

    Image and video hosting by TinyPic

    Source: 2012: Record Arctic Sea Ice Melt, Multiple Extremes and High Temperatures, WMO Press Release No 966, Nov 28, 2012
  50. Got to love Dr Inferno.

    Of relevance to this thread, "Things That Can Be Blamed Instead"

    ...
    ENSO. Same way the Moon causes sea level rise.
    ...

Prev  1  2  3  4  Next

Post a Comment

Political, off-topic or ad hominem comments will be deleted. Comments Policy...

You need to be logged in to post a comment. Login via the left margin or if you're new, register here.

Link to this page



The Consensus Project Website

THE ESCALATOR

(free to republish)

Smartphone Apps

iPhone
Android
Nokia

© Copyright 2018 John Cook
Home | Links | Translations | About Us | Contact Us