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Comments 51201 to 51250:

  1. We're heading into an ice age
    Michael, (-snip-).
    Moderator Response: [DB] Ignoring the proof citation challenges and the challenges of physical reality contravening your hypothesis put forth earlier by Michael Sweet and by Tom Curtis, it is not helpful to avoid dealing with those challenges and to blithely comment away. You must first deal with those before moving on. Soliloquy snipped.
  2. Climate of Doubt Strategy #2: Exaggerate Uncertainty
    IMO contrarians/deniers/pseudoskeptics confuse or conflate uncertainties at the margins or fringes or cutting edges of the science with uncertainty at its root. They also confuse or conflate uncertainties regarding timing with existential uncertainty. What is uncertain is how soon the Arctic sea ice will be gone in summer time. What is certain is that it will happen if nothing is done to decarbonise (and given time lags and how quickly Arctic sea ice has melted, it may be that there is nothing that can be done to stop the ice from disappearing, only restore the conditions that allow it to form). What is uncertain is when the Greenland or Antarctic land ice sheets will collapse. What is certain is that, again, if nothing is done to decarbonise, the collapses will happen. And so on, and so forth...
  3. It's El Niño
    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.
  4. Climate of Doubt Strategy #2: Exaggerate Uncertainty
    chriskoz@1: not sure it was intentional or not, but regardless, the term "effluent lifestyle" nearly made me gag with laughter...and its implicit veracity, vis-a-vis the lifestyle we Westerners so think is our birthright. To do nothing about that which we ourselves have perptrated upon our children, would be to do the *most* foolish thing humanity could conceive of. This is why I *rail* against the Moncktons of the world, for it is their path that is the truly foolish one.
  5. It's El Niño
    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.
  6. President Obama's Statement on Climate Change
    No measures have any lasting effect without the cornerstone in the battle against climate change: a global carbon tax. This becomes clear from the evolution of CO2 emissions in the last 10 years: Global CO2 emissions are rising faster than according to even the worst scenarios predicted by the IPCC, despite all efforts. We urgently need to get rid of the theorem "Every little bit helps". Because it is incorrect. To give some examples: 1. The promotion of Compact Fluerescent Lamps (CFLs) leads to an increased energy consumption. This phenomenon is called ‘Jevon’s paradox’. To explain it in economical terms: it is a consequence of the law of supply and demand. If certain goods get cheaper (in this case: the cost of one ‘lamp hour’), consumption of these goods will go up. Total energy consumption increases as a result. 2. Promoting bio-fuels, meant as a measure to slow down climate change, leads to massive deforestation, which accelerates climate change. 3. After the oil crisis in the 1970s the American Congress approved a law stating that fuel efficiency had to double in 10 years time. The American car manufacturers succeeded in this task, but the consequence was that total fossil fuel consumption went up. Clinging on to the “Every little bit helps” delusion is both useless and dangerous. Once a global carbon tax has been imposed it does make sense to improve fuel efficiency, reduce the ecological footprint, build renewable energy plants etc. but mainly as tactics to create and maintain prosperity, within the border conditions of the carbon tax.
  7. Climate of Doubt Strategy #2: Exaggerate Uncertainty
    CHRISTOPHER MONCKTON: The right response to the non-problem of global warming — first slide, please — is to have the courage to do nothing. I guess Viscount Monckton is braver than I am, or a fool. “If you fear nothing, then you are not brave. You are merely too foolish to be afraid.” Like the comments so far I use a travel analogy, in my case a train. Imagine a high speed train hears there is an obstruction further down the line. You have to apply the brakes now to avoid the obstruction, it takes along time to stop a train. Yet it could be a false alarm, the obstruction could be on the other track or cleared by the time you get there. Do you apply the brakes and play safe? Delaying your journey and later trains and losing money. Or do you gamble? By the time you know for certain you would not be able to avoid a crash if the warnings were true.
  8. Climate of Doubt Strategy #2: Exaggerate Uncertainty
    Driving a car through a wall (or down a dark steep hill) as a shortcut because of missing certainty what shape the car (and driver and riders) will be in afterwards?
  9. Climate of Doubt Strategy #2: Exaggerate Uncertainty
    It's more like not hitting the brakes on the freeway when you see a traffic jam ahead because you're not quite sure how good your brakes are, and you're not sure if the jam will clear or get worse by the time you plow into it. Normal people would consider either of those a good argument to hit the brakes early, but apparently deniers feel that you have to be 100% sure of the crash before doing anything.
  10. New research from last week 47/2012
    Just a slight error, Ari. The link to the "Classic of the Week" leads to a 2012 Cryosphere paper. Excellent post, as usual.
  11. It's El Niño
    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.
  12. It's El Niño
    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.
  13. Climate of Doubt Strategy #2: Exaggerate Uncertainty
    The arguments for action delay by such people as Michaels & Monckton are not illogical when you consider their associations and possible motivations. it is in their interest to keep FF burning because they are associated with mining/energy industry. We can even "globalise" that point and find analogy at the national level: industrialised nations have no interest in cutting emissions because their economies cannot be easily switched to low energy/alternative energy and their citizens don't want to give up the effluent lifestyle. Of course we know the nonsense misleading talk of "getting 3 world countries out of poverty with cheep energy". Those countries actually don't need "cheap energy": their citizens are used to low energy lifestyle. And sometimes they are proud of it. Take for example Cuba, a county which is way ahead of any other nation in effluence to emissions ratio, I guess some 10 times better than US or GB or Australia (where most SkS commenters including myself, live). Cubans don't need AC, big cars, water bottles shipped from Fiji to comfortably sustain their culture. And I guess, in a warming world, when those "spoiling services" are about to collapse and their consumers doomed, cultures like Cuba have the best chance to adapt and survive. So, action to stop climate change should include not just stopping FF but changing the mindset. Without the appropriate mindset, nothing will happen. Obviously, the deniers like Michaels & Monckton are the lost case, and should be incarcerated for their crimes against the Earth (they confuse the mindsets of others).
  14. It's El Niño
    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.
  15. It's El Niño
    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?
  16. It's El Niño
    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.
  17. It's El Niño
    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.
  18. It's El Niño
    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.
  19. Philippe Chantreau at 10:05 AM on 27 November 2012
    It's El Niño
    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.
  20. It's El Niño
    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?
  21. It's El Niño
    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)
  22. It's El Niño
    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. 2012 SkS Bi-Weekly News Roundup #4
    Oh boy has the start of COP18 ever set the deniers into a frenzie in Canada. On every news site I've looked at today which allows commenting, the majority of comments are rants related to how the UN is just stealing our money, the globe has been warming for 12,000 years, its a natural cycle, ect ect. The brass jokes of the woefully ill-informed have taken over today, leaving the rest of us shaking our heads (and overwhelmingly downvoted)
  24. It's El Niño
    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.
  25. It's El Niño
    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.
  26. It's El Niño
    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.
  27. It's El Niño
    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?
  28. It's El Niño
    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.
  29. It's El Niño
    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?”
  30. It's El Niño
    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?
  31. It's El Niño
    @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.
  32. It's El Niño
    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?
  33. It's El Niño
    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
  34. Philippe Chantreau at 02:43 AM on 27 November 2012
    It's El Niño
    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.
  35. It's El Niño
    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?
  36. It's El Niño
    @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.
  37. It's El Niño
    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
  38. WSJ, Sandy, and Global Warming - Asking the Right Questions
    KR, the analogy could hold: it's better to pay higher taxes to get better projections than to wait for disaster to strike and have to go to a loan shark. Perhaps it's a stretch. I'm giving this one a 60% chance of being spam.
  39. We're heading into an ice age
    Wait, didn't I see a movie about this once?
  40. Climate change evident across Europe, confirming urgent need for adaptation
    Yes John, things are looking bleak but it seems that our elected remain in cloud cuckoo land juudging by this report from the BBC Energy Bill: Households to fund £7.6bn green investment which policy looks like a cynical attempt to make renewable energy even more unpopular with those who from either NIMBY or ideological precepts are already shouting against wind farms. Roger Harrabin in a side column wrote this:
    But beyond 2020 Mr Osborne has refused to commit. He doesn't think the UK should be taking a global lead on cutting emissions while competitor economies are not following. And he thinks gas may be a cheap power source in future. So he has rejected the plan for a 2030 target for cleaning up the electricity sector. This 2030 goal is not legally binding, but it is said to be needed if the UK has a reasonable chance of meeting long-term emission targets under the Climate Change Act.
    If Mr Osborne is relying on fracking to provide much onshore gas production then he is ignoring many of the dangers that are becoming clear from North American operations. This from contamination of water supplies, potable water will become more expensive than oil by orders of magnitude in the future if these methods continue, increased seismic instability, seepage of 'waste' methane from the ground across workings and the excavation of vast tracts of land to source the special sand used in the process. If the true costs of all those problems are factored in then I doubt very much if gas is a cheap option. There may also be an element pushing for import of Canadian tar-sands oil and even the production of gas from coal. I remember the gas-works with its gas holders storing 'town gas' and also the choking atmosphere of fogs laced with the gaseous effluents from these plants. I saw parts of a programme on TV the other evening which looked at some of the pristine Indian Ocean coastline of Western Australia where plans are afoot to create a vast mineral extraction enterprise and a port facility even larger than the one already on that coast. Madness. I understand that the GWPF has been active in 'advising' the chancellor, and others in our government and is it a coincidence that Peter Lilley was in the audience at Lindzen's Westminster (side room) presentation earlier this year.
  41. Climate change evident across Europe, confirming urgent need for adaptation
    I note the article says, "Climate change is projected to increase river flooding [in N Europe]". In fact what's happening in the UK as I write this is pretty conclusive proof that this particular effect is already being observed, so much so that an insurance industry spokesperson on the BBC flagship morning news programme, 'Today', this morning stated that, "flooding is the biggest climate change threat facing UK". "The new normal." 2012 has been wetter than anyone here can remember, some villages seeing record flooding on three occasions over the last six months. The insurance implications are a time bomb for the government. The link to global warming, when finally accepted, is our best hope for finally defeating denial and making joe public and politicians alike face up to the need for real action to cut emissions.
  42. It's El Niño
    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.
  43. Climate change evident across Europe, confirming urgent need for adaptation
    Doug H @2 I think that you have correctly labeled the current politics in developed nations. We need to move towards crisis management of the situation at each available pretext as at these times what is considered possible is more up for grabs. As I see it the technical situation is a good deal better than the political one.
  44. Climate change evident across Europe, confirming urgent need for adaptation
    Paul W @ 1If we stopped burning FF today, civilisation (in developed countries at least) would fall apart. If we continue burning FF unabated, projections tell us that global civilisation will fall apart.
    1. Is there a FF trajectory that will save civilisation in advanced nations, while allowing development of Third World nations?
    2. Is there any chance of developed nations adopting such a FF trajectory>
    The answer to 1. is "maybe". The answer to 2. is "in your dreams". If ever there was a time for Divine Intervention, that time is now.
  45. President Obama's Statement on Climate Change
    Q Sounds like you're saying, though, in the current environment, we're probably still short of a consensus on some kind of attack. THE PRESIDENT: That I'm pretty certain of.
    Really? You think Republicans are not in a consensus with Democrats about Global Warming? Well, I never!
  46. We're heading into an ice age
    Tom, Thanks for the references. I checked the Rutgers snow lab and only 0.16 million km2 of snow cover remained in week 31 this year, not counting Greenland. At least the anomaly will stop going up, since all the snow is gone. A lot of permafrost is also melting, but I do not have a reference at hand. NSIDC probably has something. Robert, what is your response to this data?
  47. We're heading into an ice age
    Further to Michael Sweet's comment @269, Milankovitch cycles are supposed to initiate glacials by cool summers failing to melt snow, thereby increasing albedo with a progressive cooling over time as a result. Merely piling more snow onto a preexisting ice cap will not increase albedo, and so cannot initiate an glacial. As it happens, with a warmer world, NH summer snow extent has decreased significantly, the reverse of that required to initiate a new glacial (July shown): What is more, ice caps are not accumulating ice on Baffin Island, rather they are melting. Zdanowicz et al (2012) report:
    "At latitude 67°N, Penny Ice Cap on Baffin Island is the southernmost large ice cap in the Canadian Arctic, yet its past and recent evolution is poorly documented. Here we present a synthesis of climatological observations, mass balance measurements and proxy climate data from cores drilled on the ice cap over the past six decades (1953 to 2011). We find that starting in the 1980s, Penny Ice Cap entered a phase of enhanced melt rates related to rising summer and winter air temperatures across the eastern Arctic. Presently, 70 to 100% (volume) of the annual accumulation at the ice cap summit is in the form of refrozen meltwater. Recent surface melt rates are found to be comparable to those last experienced more than 3000 years ago. Enhanced surface melt, water percolation and refreezing have led to a downward transfer of latent heat that raised the subsurface firn temperature by 10°C (at 10 m depth) since the mid-1990s. This process may accelerate further mass loss of the ice cap by pre-conditioning the firn for the ensuing melt season. Recent warming in the Baffin region has been larger in winter but more regular in summer, and observations on Penny Ice Cap suggest that it was relatively uniform over the 2000-m altitude range of the ice cap. Our findings are consistent with trends in glacier mass loss in the Canadian High Arctic and regional sea-ice cover reduction, reinforcing the view that the Arctic appears to be reverting back to a thermal state not seen in millennia."
    Fisher et al (2012) report:
    "There has been a rapid acceleration in ice-cap melt rates over the last few decades across the entire Canadian Arctic. Present melt rates exceed the past rates for many millennia. New shallow cores at old sites bring their melt series up-to-date. The melt-percentage series from the Devon Island and Agassiz (Ellesmere Island) ice caps are well correlated with the Devon net mass balance and show a large increase in melt since the middle 1990s. Arctic ice core melt series (latitude range of 67 to 81 N) show the last quarter century has had the highest melt in two millennia and The Holocene-long Agassiz melt record shows that the last 25 years has the highest melt in 4200 years. The Agassiz melt rates since the middle 1990s resemble those of the early Holocene thermal maximum over 9000 years ago."
    Sharp et al (2011) report:
    "Canada's Queen Elizabeth Islands contain ∼14% of Earth's glacier and ice cap area. Snow accumulation on these glaciers is low and varies little from year to year. Changes in their surface mass balance are driven largely by changes in summer air temperatures, surface melting and runoff. Relative to 2000–2004, strong summer warming since 2005 (1.1 to 1.6°C at 700 hPa) has increased summer mean ice surface temperatures and melt season length on the major ice caps in this region by 0.8 to 2.2°C and 4.7 to 11.9 d respectively. 30–48% of the total mass lost from 4 monitored glaciers since 1963 has occurred since 2005. The mean rate of mass loss from these 4 glaciers between 2005 and 2009 (−493 kg m−2 a−1) was nearly 5 times greater than the 1963–2004 average. In 2007 and 2008, it was 7 times greater (−698 kg m−2 a−1). These changes are associated with a summer atmospheric circulation configuration that favors strong heat advection into the Queen Elizabeth Islands from the northwest Atlantic, where sea surface temperatures have been anomalously high."
    Finally, Schrama et al, (2011) report:
    "In this paper we discuss a new method for determining mass time series for 16 hydrological basins representing the Greenland system (GS) whereby we rely on Gravity Recovery and Climate Experiment (GRACE) mission data. In the same analysis we also considered observed mass changes over Ellesmere Island, Baffin Island, Iceland, and Svalbard (EBIS). The summed contribution of the complete system yields a mass loss rate and acceleration of −252 ± 28 Gt/yr and −22 ± 4 Gt/yr2 between March 2003 and February 2010 where the error margins follow from two glacial isostatic adjustment (GIA) models and three processing centers providing GRACE monthly potential coefficient sets. We describe the relation between mass losses in the GS and the EBIS region and found that the uncertainties in all areas are correlated. The summed contribution of Ellesmere Island, Baffin Island, Iceland, and Svalbard yields a mass loss rate of −51 ± 17 Gt/yr and an acceleration of −13 ± 3 Gt/yr2 between March 2003 and February 2010. The new regional basin reconstruction method shows that the mass loss within the southeastern basins in the GS has slowed down since 2007, while mass loss in western basins increased showing a progression to the north of Greenland."
    The reported ice mass loss for Baffin Island alone is -10.8 Gt/year. In sum, ice sheets and ice caps in the Canadian archipelago are loosing ice with warmer weather, the opposite to the effect predicted by Robert. His theory is therefore falsified.
  48. Climate change evident across Europe, confirming urgent need for adaptation
    While this is a good report and I don't doubt it's findings the forward projections of adapting seem short sighted. Do we stop all building below 25 meters above sea level so we can focus our future resources on what will still be left. In order to be able to adapt I would have thought a move to directly ASAP ending fossil fuel use is needed. A bit more than just cutting back! Followed by moving towards those energy methods that put carbon back in the ground at least to some extent. Since the 2 degree C so called safety margin is being found to have less and less meaning as we are now headed towards well over 3 C. Also 1.5 degrees C increase over the pre industrial level (where we would get to if we stopped fossil fuel use now) looks more like the disaster point. The equilibrium sea level rise is more than the global economy can afford to adapt to. So logically this implies that prevention is now even more important than adaption. The focus towards adaption while pragmatic is still well short of pragmatic enough. The lameness about not (or giving up on) reducing CO2's rise to zero rise is more than a little "interesting".
  49. We're heading into an ice age
    Robert, Why did scientists stop producing papers that you can cite over a decade ago? Can you cite a paper that suggests that warm temperatures over Baffin Island initiated the ice ages? The Milankovitch cycles are generally presumed to initiate the ice ages by cooling the Northern Hemisphere. This slow cooling allows snow to accumulate in Northern Canada. Please provide a recent citation that claims warm water in the Baffin area initiated the ice ages. Your supposition that an ice free arctic, deduced by eyeballing the Cyrosphere Today graph, will cause snow to accumulate is the opposite of the snow records observed at the National Snow lab at Rutgers. Those records show a dramatic decrease in the summer snow levels across the Northern Hemisphere.
  50. It's El Niño
    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.

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