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At a glance - Evidence for global warming

Posted on 28 November 2023 by John Mason, BaerbelW

On February 14, 2023 we announced our Rebuttal Update Project. This included an ask for feedback about the added "At a glance" section in the updated basic rebuttal versions. This weekly blog post series highlights this new section of one of the updated basic rebuttal versions and serves as a "bump" for our ask. This week features "Evidence for global warming". More will follow in the upcoming weeks. Please follow the Further Reading link at the bottom to read the full rebuttal and to join the discussion in the comment thread there.

Fact-Myth Warming

At a glance

It's now 14 years since Sarah Palin was on the record as having provided the above quote, at a logging conference in California. In that time, much has happened in the world of climate change. We can have a quick catch-up, by examining the 2022 State of the Climate report, published in the Bulletin of the American Meteorological Society in 2023.

In 2022, the carbon dioxide concentration in the atmosphere rose to 417 ppm. That's 50% greater than the pre-industrial level. Global mean methane abundance was 165% higher than its pre-industrial level, Nitrous oxide was 24% higher.

Record or near-record heat was widespread in 2022 and even more so in 2023. In 2022, Europe observed its second-warmest year on record, with sixteen individual countries observing record warmth at the national scale. Records tumbled, many with huge increases as summer heatwaves plagued the region. On 18 July, 104 weather-stations in France broke their all-time temperature records in a single day. On the 19th, England recorded a temperature of 40°C for the first time. China experienced its second-warmest year and warmest summer on record. In the Southern Hemisphere, the average temperature across New Zealand reached a record high for the second year in a row. Western Australia reached 50.7°C on 13 January, equaling Australia's highest temperature on record.

Sea-surface temperature patterns in the tropical Pacific were characteristic of La Niña, a phenomenon that should have mitigated against atmospheric heat gain at the global scale. However, the annual global surface temperature across land and oceans was among the six highest in records dating as far back as the mid-1800s. 2022 was the warmest La Niña year on record.

At the time of writing, there is still about a month of 2023 to run. Yet once again we have record-breaking temperatures, with some records smashed by huge margins, so that 2023 looks as though it may well go down as the hottest on record.

'Snake oil science'? No, these are records of things actually happening, right now. Not only are they being recorded, they are being witnessed by countless people worldwide. They add to the growing mountain of scientific evidence, showing without any doubt that Earth's climate system is overheating, as predicted by the laws of physics from more than a century ago. If some politician or other insists to the contrary, just ask yourself what particular expertise entitles them to make such utterances? Are they really smarter than all the tens of thousands of scientists who work hard to collect and analyse the data?

Beware. politicians tend to be good at talking politics on most topics and they are especially adept at telling people what they want to hear. But in cases like this, we can clearly see that events have a tendency to catch up with them in the longer term. Beware.

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!

Click for Further details

In case you'd like to explore more of our recently updated rebuttals, here are the links to all of them:

Myths with link to rebuttal Short URLs
Ice age predicted in the 1970s
It hasn't warmed since 1998
Antarctica is gaining ice
CRU emails suggest conspiracy
What evidence is there for the hockey stick
CO2 lags temperature
Climate's changed before
It's the sun
Temperature records are unreliable
The greenhouse effect and the 2nd law of thermodynamics
We're heading into an ice age
Positives and negatives of global warming
Global cooling - Is global warming still happening?
How reliable are climate models?
Can animals and plants adapt to global warming?
What's the link between cosmic rays and climate change?
Is Al Gore's An Inconvenient Truth accurate?
Are glaciers growing or retreating?
Ocean acidification: global warming's evil twin
The human fingerprint in global warming
Empirical evidence that humans are causing global warming
How do we know more CO2 is causing warming?
Explaining how the water vapor greenhouse effect works
The tricks employed by the flawed OISM Petition Project to cast doubt on the scientific consensus on climate change
Is extreme weather caused by global warming?
How substances in trace amounts can cause large effects
How much is sea level rising?
Is CO2 a pollutant?
Does cold weather disprove global warming?
Do volcanoes emit more CO2 than humans?
How do human CO2 emissions compare to natural CO2 emissions?
Climate scientists could make more money in other careers
How reliable are CO2 measurements?
Do high levels of CO2 in the past contradict the warming effect of CO2?
What is the net feedback of clouds?
Global warming vs climate change
Is Mars warming?
How the IPCC is more likely to underestimate the climate response
How sensitive is our climate?
Evidence for global warming


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Comments 1 to 45:

  1. We have many ways of measuring global warming. Urban areas, rural areas,oceans, the middle, and upper atmosphere. Sea level rise is also an indication of warming. All these show a similar warming trend. How much more do people want to be convinced? There really isn't any part of the planetary system left to measure.

    If we were reliant purely on land surface data in cities for example,  I would be scepetical. One data set might be flawed. But the chances of so many multiple data sets all being flawed and in the same direction is effectively zero.

    Sarah Palin seems like a typical example of a lay person who thinks she knows better than the climate experts. Of course its good to discuss things and question if the experts are right, but remember the experts know things you dont know and small details are important in science.

    Another expample of someone out of their depth is John Clauser, a physicist with a nobel prize in quantum physics and an outspoken anthropogenic climate change sceptic despite the fact he has never published any research related to climate change or formally specialised in something like atmospheric physics. It hasn't stopped him telling everyone that climate science is all wrong. He has made many indisputably false statements sometimes by using very out of date information. So even scientists outside their area of expertise can fool themselves. Good commentary here:

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  2. "All these show a similar warming trend."

    Not the middle of the equatorial Pacific.  The temperature variation there is also not well understood because El Nino & La Nina cycles dominate and these are difficult to predict more than a year in advance.  

    "SST trends in the equatorial Pacific Ocean are especially controversial due to the discrepancy in the sign of the trend in the central and eastern Pacific among various SST datasets (Vecchi et al. 2008; Karnauskas et al. 2009; Deser et al. 2010a)"

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  3. @#2: in fairness to nigelj, one has to look fairly hard for maritime areas that do not show a "similar warming trend". Granted, they are interesting because the obvious question is, "why", However they are also a tiny minority.

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  4. Paul Pikute @2,

    I went to read the paper you quoted and linked to learn more about the point you made.

    The first thing I learned, almost immediately, is that the paper is from 2012. I immediately wondered if a newer paper with more recent data would conclude similar results.

    However, reading the full Introduction of the paper was all I needed to do to learn a lot. A more recent paper would not be required to clarify the issue you raised.

    The quote you shared is near the beginning of the Introduction. I repeat the quote ... but include the statement immediately following it.

    “SST trends in the equatorial Pacific Ocean are especially controversial due to the discrepancy in the sign of the trend in the central and eastern Pacific among various SST datasets (Vecchi et al. 2008; Karnauskas et al. 2009; Deser et al. 2010a). However, the disparity in trend largely arises from the coverage and quality of in situ observations in the centennial record, particularly during the early decades of the twentieth century (Deser et al. 2010a; Giese et al. 2010).”

    Why did you stop reading at the end of the quote you shared? If you did read the full Introduction why did you only quote the bit that you did?

    If you had read the entire Introduction you would have also encountered the following:

    “The purpose of this paper is to understand the linear trends in association with the leading patterns of tropical Pacific SST variability and in key SST regions of the tropical Pacific during 1950–2010. Because of prior work indicating a positive trend in the El Niño Modoki, the significance of this pattern and the zonal gradient of equatorial Pacific SSTs is closely examined. Because of limited data coverage prior to the Second World War, we elected to not use the full SST datasets that begin in the nineteenth century. While centennial trends are not assessed here, we note that using a reduced period results in more consistent linear trends in SSTs over the 61-year record (Fig. 1), which are significantly positive throughout the tropical Pacific Ocean.” (bolding by me)

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  5. Paul Pukite,

    My apologies for transposing letters in your name.

    I try to be careful. I have a history of crossing up 'Left and Right-hand'. So I am aware that I am likely to make mistakes like that.

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  6. To add a touch of humor to this thread :-

    While scanning through the well-fertilized field of WUWT  blogsite, I found myself being directed to a new Youtube video of a day or two ago, where the author [Paul] is in strident denial of AGW, Hockey Stick, etc.

    Such videos are typically not worth viewing (unless you are "in traction" in a hospital bed for the next 3 months, while your shattered bones heal).   But a quick scan through the video's comments column may turn up a gem or so.   And the gem was a two-liner :-

    [quote]   "Thanks, Paul.

    You and Tony Heller are beacons of sanity in this crackpot World"


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  7. one has to look fairly hard for maritime areas that do not show a "similar warming trend"

    As far as I can tell, when one searches for equatorial Pacific ocean SST time-series, you only get NINO34, NINO4, etc data. These show no or very little trend, being dominated by ENSO variations.  As far as I can tell, they have not been detrended, but do have the annual seasonal temperature cycle removed. 

    Proxy records to demonstrate the hockey stick contain many samples from coral ring measurements.  Yet, these also show very little trend which is not surprising as most coral is found in tropical or equatorial waters, where the SST also shows little trend.  That's why most hockey stick discussion is on tree ring data. 

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  8. Paul Pukite @7,

    One has to try very hard to evade evidence and understanding that contradicts a preferred unjustified belief. You appear to have chosen to not address the evidence and understanding presented in my comment @4 that shows that your initial claim @2 is non-sense.

    As mentioned by Eclectic @6 sites like WUWT are a swirl of laughable efforts to evade learning about things that contradict 'preferred beliefs'. Do an internet search of "belief vs understanding". There is an important difference. The pursuit of learning to better understand things requires being open to revision of beliefs.


    Pursuing a resistance to learning can be popular. Sites like WUWT and Dr. Roy Spencer's are proof of that.

    Thanks for giving us all a laugh here without having to venture into the Non-Sense-Land of WUWT and Dr. Spencer's. Admittedly they would be funnier if the type of people they attract did not have any significant influence on leadership actions. But, tragically, popular non-sense can significantly compromise the actions of leaders who are reliant on getting some support from people who are tempted to believe non-sense.

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  9. Paul Pukite:

    This map shows warming trends for the entire world for the years 2015-2019.  It uses a baseline of 1951-1980.  I note that most of the oceans have a positive anomaly.  You are just not looking.  source

    global warming map

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  10. As mentioned by Eclectic @6 sites like WUWT are a swirl of laughable efforts to evade learning about things that contradict 'preferred beliefs'.

    Eclectic mentioned something about a "Paul" at WUWT, apparently thinking that's me.  Why would he think that? Does he have evidence?  I have been blogging since 2004 and have yet to write anything "in strident denial of AGW, Hockey Stick, etc"  and certainly haven't been featured in a YouTube video.   I guess my crime is being involved in research on El Ninos.

    Frankly, I don't find AGW that interesting as it seems fairly well understood.  More difficult is to predict an El Nino a few years in advance.  

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  11. Paul Pukite @10 :

    No, no, no . . . no such disrespect for you, Paul Pukite.

    On the Denialist video mentioned @6 above, the "Paul" mentioned was a certain Paul Burgess, the author of that guff  [his channel label being "Climate Realism with Paul Burgess"].   Most readers here will see large red flags, when terms like Climate Realism . . . CAGW . . . Galileo . . . quotations from Feynman etc,etc . . . are placed prominently.

    It was just an amusing co-incidence of first names.  Sorry for the alarm.  I should have resisted the temptation to omit the Burgess !

    Paul Pukite, I have seen your name often in the comments columns of sober & respectable online climate threads.  It seemed very unlikely that Burgess would be your alter ego.

    Paul Burgess is a name I do not recall seeing at WUWT.   Nor do I recall seeing any videos by him (nor any alluded to) . . . and I did not bother to see more than a few seconds of his video  ~ since life is too short to spend watching video explications by climate deniers / Flat Earth exponents / anti-vaxxers / perpetual-motion machine inventors / and suchlike.

    But comments columns from the Usual Denialist Suspects . . . can be skimmed very quickly, while keepiing an eye out for gems !

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  12. Paul Pukite @10,

    Hilarious. You appear to still be spinning ways to evade learning, just like members of the WUWT crowd.

    Until you seriously address the counter-points I have presented (essentially pointing out the easy to obtain better understanding of the 2012 report you unjustifiably cherry-picked a quote from in your comment @2) the evidence here indicates you are 'one of them'.

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  13. One Planet Only Forever

    Here is the NINO3 SST time-series, which is taken from the equatorial Pacific, and note that it is difficult to discern a warming trend.   That's just the way it is in the ocean, which acts like a large heat sink, with the colder water below the therrmocline occasionally approaching the surface leading to colder La Nina episodes.   



    I am pretty certain this is not detrended as it the detrended version is also here an it appears similar


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  14. I don't think PP is a denialist. Have seen his comments at RC. We sometimes just get on edge and jump to the conclusion that anyone who says "flat trend" is a denialist because its a common denialist talking point. 

    We know the oceans as a whole have warmed considerably since the 1980s. But then you do have a few areas with cooling like the cold blob in the nothern atlantic. 

    I'm eyeballing Paul Pukete's graphs of the equatorial pacific and at best I can only see a very slight warming trend from around 1970 - 2022. I mean it does look flat or near flat, so I looked for an explanation and this is interesting. I have highlighted the main pargraphs only:. It seems to be consistent with what PP is saying.

    Part of the Pacific Ocean Is Not Warming as Expected. Why? BY KEVIN KRAJICK |JUNE 24, 2019

    State-of-the-art climate models predict that as a result of human-induced climate change, the surface of the Pacific Ocean should be warming — some parts more, some less, but all warming nonetheless. Indeed, most regions are acting as expected, with one key exception: what scientists call the equatorial cold tongue. This is a strip of relatively cool water stretching along the equator from Peru into the western Pacific, across quarter of the earth’s circumference. It is produced by equatorial trade winds that blow from east to west, piling up warm surface water in the west Pacific, and also pushing surface water away from the equator itself. This makes way for colder waters to well up from the depths, creating the cold tongue.

    Climate models of global warming — computerized simulations of what various parts of the earth are expected to do in reaction to rising greenhouse gases — say that the equatorial cold tongue, along with other regions, should have started warming decades ago, and should still be warming now. But the cold tongue has remained stubbornly cold.
    Why are the state-of-the-art climate models out of line with what we are seeing?

    Well, they’ve been out of line for decades. This is not a new problem. In this paper, we think we’ve finally found out the reason why. Through multiple model generations, climate models have simulated cold tongues that are too cold and which extend too far west. There is also spuriously warm water immediately to the south of the model cold tongues, instead of cool waters that extend all the way to the cold coastal upwelling regions west of Peru and Chile. These over-developed cold tongues in the models lead to equatorial environments that have too high relative humidity and too low wind speeds. These make the sea surface temperature very sensitive to rising greenhouse gases. Hence the model cold tongues warm a lot over the past decades. In the real world, the sensitivity is lower and, in fact, some of heat added by rising greenhouse gases is offset by the upwelling of cool water from below. Thus the real-world cold tongue warms less than the waters over the tropical west Pacific or off the equator to the north and south. This pattern of sea-surface temperature change then causes the trade winds to strengthen, which lifts the cold subsurface water upward, further cooling the cold tongue.


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  15. Makes sense. The NINO3 time-series above is closer to Peru and the cold tongue than the equatorial Pacific NINO34 and NINO34 indices. Another even closer to Peru is the NINO12 time-series, which also doesn't show much of a trend.

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  16. Paul Pukite @13,
    Your latest comment does not address the questions I raised regarding your initial comment and the ways you have commented regarding this point.
    @2 You said “...Not the middle of the equatorial Pacific. The temperature variation there is also not well understood because El Nino & La Nina cycles dominate and these are difficult to predict more than a year in advance.”

    I am open to learning (even though I still struggle with right vs left hand). Years ago I learned that the difficulty in ‘predicting the ENSO’ does not affect the ability to evaluate trends in the equatorial Pacific SST. Due to the trend of SST in the Niño 3.4 region (the middle of the equatorial Pacific) NOAA had revised their methodology for the Ocean Nino Index (ONI) values to be relative to a regularly updated baseline.

    The following is from the NOAA webpage (linked here) that presents the ONI values identifying the “Cold & Warm Episodes by Season”.

    “DESCRIPTION: Warm (red) and cold (blue) periods based on a threshold of +/- 0.5oC for the Oceanic Niño Index (ONI) [3 month running mean of ERSST.v5 SST anomalies in the Niño 3.4 region (5oN-5oS, 120o-170oW)], based on .”centered 30-year base periods updated every 5 years.”\

    And the linked NOAA webpage for “centered 30-year base periods updated every 5 years” shows the annual temperature curves for each of the 30-year base periods. In that presentation there is an undeniable warming trend since 1950.

    What you will notice is that the NOAA ONI and the related base periods start in 1950. This ties directly to the paper you made the unrepresentative quote from mistakenly believing that it supported your incorrect ‘declared belief’ about the middle of the equatorial Pacific.

    In closing I will say that a statistical evaluation of the data points is the proper way to determine a trend in the data. However, when I look at the NINO3 graph you have chosen to share I see a warming trend for the portion from 1950 to 2010. That would be consistent with the more valid evaluation of the data done by the authors of the paper you misrepresented in your comment @2.

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  17. nigelj @14,

    Paul Pukite’s set of comments here starting with his comment @2 are the matter of concern. Though there is a difference between current developed models and actual observations, that difference is not related to, and does not explain or excuse, Paul’s resistance to learning about the reality of a warming trend throughout the equatorial Pacific.

    Note that a warming trend since 1950 appears to also be in the graph of Nino12a that Paul Pukite selected to present @15. Prior to 1950 can justifiably be excluded from the evaluation because of the reasons given by the authors of the 2012 paper Paul misrepresented and still has not indicated he has learned about.

    Note that the NOAA information I most recently shared in my latest response to Paul also does not evaluate the SST before 1950 (except for using pre-1950 values to determine the earlier centered 30-year base period values).

    Also note that the global average surface temperature had a significant increase of temperature after 1950 compared to the rate of increased prior to 1950. Using the SkS Temperature Trend Calculator and GISTEMPv4:

    • trend: 1880 to 1950 is 0.038+-0.021 C / decade (little warming)
    • trend: 1950 to today is 0.152+-0.018 C / decade (lots of warming).

    Also note that it is well understood that the land temperatures and polar regions have been warming much more rapidly than the equatorial SST. So the equatorial SST warming since 1950 will be significantly less than the 1 degree C global average since 1950 (much harder to see in a chart with monthly data value swings of up to 8 degrees C like the NINO12 image presented by Paul @15 - statistical evaluation is the proper way : not "I think I see what I think I see").

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  18. There could be a warming trend buried in the NINO3 time-series but it's difficult to extract because of the large El Nino and La Nina excursions — note that they exceed 4C on the positive side and almost that much on the negative side. Remember that this region is the source of energy (or sink of energy) which can heat up (or cool down) the world for months at a time so it may be understandable that the AGW trend gets buried. 

    It's difficult to do statistical trend analysis on such a time-series without a model of the underlying "nuisance" signal. Since I have been doing mainly ENSO research, having published and presented at several AGU/EGU meetings on the topic, I tend to think of the AGW as the nuisance — tho, since it's so small it's not much a nuisance.  On the other hand if you're iterested in the AGW trend here, the ENSO signal is a huge nuisance.

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  19. Paul Pukite,

    The SkS Temperature Trend Calculator does a statistical analysis of the temperature data that 'includes ENSO nuisance'. The same can be done for the SST data.

    And you still have not addressed the points I have made regarding your inaccuate and incorrect beginning. WUWT?

    I will agree that improving the ability to forecast ENSO events is important and helpful work. But the points you have tried to make-up on this string are not helpful.

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  20. Paul Pukite,

    I included some points in my comment @18 that directly (interestingly) relate to your comment @19.

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  21. Paul Pukte @10,

    When you present a graph and say "my eyecrometer detects no trend" with no statistical analysis you are wasting our time.   Likewise when you say "I am pretty certain this is not detrended" you are wasting our time.  If you are not absolutely certain the data is not detrended go find out for sure.

    When I go to your data source I find the graph you have presented has this label:

    "cutting out region defined by mask ersstv5 nino3, operating on NOAA ERSSTv5 (in situ only), SSTA normalized to 1981-2010, Nino3 index minus 20S-20N average SST, normalised by a factor" my emphasis

    It appears to me that your graph shows the anomaly in the Nino3 area  minus the trend in the tropical oceans.  Since the illustration that I posted in post at 9 shows that the tropical ocean has a clear waring trend.  You have ignored since it contradicts your claims.  It appears to me that your graph shows that the ENSO anomally has not changed compared to the rest of the ocean, not that the temperature has not risen in the Nino 3 area as you claim.

    I note the the older data in your graph must have large error bars.  I also note that small areas of the globe have much more noise so it is hard to detect the warming signal, especially by eyecrometer.

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  22. OPOF & M Sweet.  You guys sound correct in your technical analysis and correct that  the equatorial part of the pacific ocean is warming (and I also thought the graphs posted by PP showed a slight warming after 1970). But the warming in a narrow band along the equator is at a significantly slower rate than  the pacific ocean as a whole (roughly 0.2 compared to 0.6 in the maps in  link I posted). The map posted by MS is a bit too large scale to pick up this level of detail and difference. 

    This basic pattern is important, and the  explanation seems quite good. I think that is the main point.

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  23. It's interesting to compare NINO34 almost-raw (annual cycle is still removed) and de-trended 

    This is raw from KNMI explorer site


    This is de-trended

    So there appears to be a ~0.5 degree trend removed over the time span.  All my original comments stated were that the trend was difficult to discern because of the dominating ENSO variations and those are not understood very well.  That's all I said, go back and check.

    In terms of optimal control theory, properly removing the signal (a warming trend) from the noise (ENSO variations) is only possible if a model for the noise is known. If the noise is statistically random with no trend, it's practical to create e.g. a Kalman filter to optimally remove  the noise.  However, if the noise of ENSO carries long-period multidecadal fluctuations, such as is observed with the AMO on the Atlantic side or the decadal PDO in the north Pacific, then it becomes much more challenging to discriminate the noise from the signal. That's because climate scientists still have no validated model for ENSO, being unable to predict it more than a few years in advance.   

    The ~1/2 degree warming in the NINO34 time-series above is in all likelihood a real AGW effect but my original remark was only in pointing out that the comment by Nigel J: "All these show a similar warming trend" could be challenged.  He was OK with my remark as he found the case of the Pacific cold tongue research, which is described by NINO12 (and even more diffficult to extract the trend) and that the map by MS doesn't show this at the granularity needed.  So are the rest of you speaking for him?   

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    Moderator Response:

    [DB] Please limit image widths to 450.  Thanks!

  24. Paul Pukite @23,

    I will continue to pursue the points I raised regarding your comment @2.

    I am confident that nigelj’s comment about similar trends was regarding ‘a trend like the global average surface temperature data - warming rather than cooling with more significant warming occurring after 1950 than prior to 1950’.

    Your comment @2, and later comments except for your latest @23 (sort of), appear to insist that it is not possible to have confidence regarding a warming trend in the NINO 3.4 region (the middle of the equatorial Pacific).

    Your comment @2 starts with:

    "All these show a similar warming trend." [nigelj’s point]
    Not the middle of the equatorial Pacific. (your response)

    As my comments should indicate, I learned from and accepted nigelj’s finding of an explanation about the current models indicating a larger amount of warming in the equatorial Pacific (especially the east part) than the actual observations. However, as I commented, that does not alter the incorrectness of your comment @2. But you do appear to have finally accepted your incorrectness (sort of) by ‘seeing’ a warming trend in the NINO 3.4 SST data.

    However, I am still confident that it is incorrect to declare that having confidence that ‘the NINO 3.4 SST historical data indicates warming similar to the global average surface temperature data’ requires an accurate explanation for the trend being lower than the current global climate models for that region and it requires that understood influence to be removed from the SST values.

    The data is what it is regardless of the mechanisms producing it. Large variations of the temperature data simply requires a longer duration of the data set to have confidence that there is a warming trend. And a lower trend rate will also require a longer data set to establish confidence.

    The NOAA presentation of the centered 30-year base periods (linked here) that I provided a link to in my comment @16 helpfully presents the trend of the SST NINO3.4 data set in spite of significant variations in the data values. Each 30-year period contains a substantial variety of the variation. Comparing the 5 year steps for the data starting in 1936 shows that there is indeed a recent trend (more significant after 1950 than before 1950 – consistent with the NINO3.4 chart you included in your comment @23). The 1966 to 1995 values, and all the more recent ones, are clearly warmer than the earlier ones. However, it also shows that the ENSO perturbations in the data are large enough to make the warming trend hard to be confident of, even appearing to potentially be a cooling trend in a shorter data set. The 1981 to 2010 results are not clearly warmer, and may even be cooler, than 1976 to 2005.

    Global average surface temperature data evaluations using the SkS Temperature Trend Calculator (linked here) can also provide an example supporting my confidence that the ‘noise’ of ENSO variations do not need to be removed to be able to have confidence regarding a trend.

    As I indicated in my comment @17, using the GISTEMPv4 dataset in the SkS Temperature Trend Calculator (linked here) the trend of the data after 1950 is 0.152+-0.018 C / decade (high confidence of a warming trend). I add the following set of shorter recent time periods and the resulting trend and level of confidence (2 sigma value compared to trend value):

    Years                  Trend +- 2 sigma
    2016 to 2023 = -0.148 +- 0.513
    2015 to 2023 = -0.066 +- 0.428
    2014 to 2023 = +0.074 +- 0.379
    2013 to 2023 = +0.180 +- 0.331
    2012 to 2023 = +0.244 +- 0.289
    2011 to 2023 = +0.284 +- 0.249
    2010 to 2023 = +0.262 +- 0.220
    2005 to 2023 = +0.229 +- 0.129

    The longer the time period is the more confidence there is in the evaluated trend. Admittedly the global average surface temperature variation in the evaluations is only about 2 degrees C. So a longer time period would be expected to be required for the NINO SST values because they have larger variation of temperature and a smaller trend. But confidence regarding the trend can still be established without a detailed understanding of the mechanisms at play. And I am confident that the authors of 2012 report you (mis)quoted in your comment @2 had reason to be confident with their evaluation and reporting (repeating part of the quote I had included in my comment @4)

    “...While centennial trends are not assessed here, we note that using a reduced period results in more consistent linear trends in SSTs over the 61-year record (Fig. 1), which are significantly positive throughout the tropical Pacific Ocean.”

    What the authors of the paper observed and explained, was that the pre-1950 data was not as reliable as the post-1950 data. And since the main interest is ‘warming similar’ to the global average surface temperature which has more significant warming since 1950 than before 1950, the earlier SST values are not that important.

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  25. I don't think you have any idea what my objective is.  I frankly don't worry about modeling AGW as that's in good hands, IMHO.  Instead, what I have been trying to do the last several years is model natural climate variations such as ENSO, AMO, PDO, etc.  You may find it odd, but not observing a large contribution of an AGW signal in a time-series such as NINO34 actually makes it easier to do the modeling since the signal vs noise discrimination is more apparent. In other words, the underlying trend is so small relatively speaking that it doesn't matter if the time-series is detrended or not when fitting a model to the data.

    So based on my actual research interests, I would much rather discuss ideas concerning forcing factors behind ENSO — including tidal & annual — than deconstructing my phrasing in a tossed-off comment. If you want to delve into modeling of the geophysical fluid dynamics and how neural nets and machine learning may be helping in revealing patterns instead of pedantic point-scoring, I am game.  I will grant you a win on all the petty stuff as you seem so determined to play gotcha on a comment I made based on dealing with the data for years now.

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  26. @Paul#25:

    If that's your motivation it seems well and good, but why did you choose to interject on this thread?

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  27. Paul Pukite,

    At post two you said "Not the middle of the equatorial Pacific." Referring to  the comment "All these show a similar warming trend." 

    At post 7 you said "when one searches for equatorial Pacific ocean SST time-series, you only get NINO34, NINO4, etc data. These show no or very little trend,"

    I entered the thread to show that your comments were false.  My illustration at post 9 clearly demonstrates that you were incorrect.  You posted a graph at post 13 claiming no trend, asserting that the graph had not been detrended.  My post at 21 showed your graph was detrended and your claims of no trend in the tropical ocean are simply false.

    Now at 23 you post a graph that is actually not detrended and use your eyecrometer to claim your graph is more informative than my illustration.  Using my eyecroneter on my illustration I see clearly that the trend is closer to one degree.  If you put a least squares line on your graph we would have data instead of idle speculation. All these trends can easily be Googled, you are simply not looking.

    I have proved beyond doubt that your claim that the tropical oceans "show no or very little trend," is completely false.  The fact that you produced a graph that was not detrended and showed a trend after claiming a detrended graph showed there was no trend indicates that you are not interested in a discussion of the science here. 

    If you want to speculate on ENSO causes go for it  As I understand it, ENSO is essentially random on a yearly basis.

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  28. I note that Arhennius predicted in 1896 that the tropics would heat up slower that the poles and the ocean would heat up slower than the ocean.  Since the global average heating is about 1.2 C, we woud expect less than 1 C warming in the tropical ocean.

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  29. Paul Pukite,

    I like John Mason’s question @26. But would extend it as follows: “...why did you choose to interject on this thread...” the way that you did @2?

    Though you have not directly addressed the questions I raised @4 regarding your comment @2, your latest comments appear to indicate an awareness that it was incorrect to state that there was no similar warming in “the middle of the equatorial Pacific” [quote from you @2] (I agreed that it is worthy of being thrown away). But I still do not see indications of awareness that it was also wrong to try to justify that incorrect assertion by misrepresenting the paper you linked @2 with a ‘quote-clearly-out-of-context’.

    Making incorrect statements with questionable or made-up justifications and then arguing against attempts at clarification and correction of the incorrect belief is similar to the behaviour of the regular denizens of sites like WUWT and Dr. Roy Spencer.

    I wish you luck in your endeavours to ‘constantly learn more about ENSO – constantly changing your mind as you learn more’.

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  30. "If that's your motivation it seems well and good, but why did you choose to interject on this thread?"

    Had an account here for many years and thought I would test the waters for discussion on bleeding-edge research, which is what ENSO is all about.  I do have my own blog so it's not like an alien thing for me to raise a discussion point,


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  31. @Paul #30:

    Fair enough and I have encountered you at RC too, but it might be more appropriate to post about ENSO in a thread specifically about ENSO, for example:

    That page has not yet been updated like many of our rebuttals, but it will be in due course.

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  32. Because the present  post is mentioning ENSO

    "Sea-surface temperature patterns in the tropical Pacific were characteristic of La Niña, a phenomenon that should have mitigated against atmospheric heat gain at the global scale. However, the annual global surface temperature across land and oceans was among the six highest in records dating as far back as the mid-1800s. 2022 was the warmest La Niña year on record.

    At the time of writing, there is still about a month of 2023 to run. Yet once again we have record-breaking temperatures, with some records smashed by huge margins, so that 2023 looks as though it may well go down as the hottest on record."

    As it turns out we are now in the midst of a definitely emerging El Nino. The ENSO cycles can transiently override the gradual warming of AGW, so this is a factor to point out. 



    There was a long-running discussion on ENSO at the Azimuth Project forum started in 2014 that recently ended.  The original motivation was  to collaborate and analyze ENSO data and consider different math approaches to modeling the cycles, as the organizers of the project were skeptical as to a chaotic or random origin for ENSO. Alas, the owner of the site shut it down and wiped out the entire archive.  Fortunately, some of the open source code for the effort was kept on a GitHub repo and I was able to grab ownership and keep that alive, so a remnant discussion is available for those that have GitHub accounts.


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  33. @Paul #32:

    "As it turns out we are now in the midst of a definitely emerging El Nino. The ENSO cycles can transiently override the gradual warming of AGW, so this is a factor to point out. "

    I think most readers on here are well aware that the EN phase of ENSO overdubs the AGW signal on a temporary basis!

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  34. But you asked why I commented on this post with respect to ENSO, when it was you that mentioned La Nina in the the post itself.  But we're no longer in a La Nina regime but in El Nino.

    I just wanted to test the waters here again to see if this site has changed its approach to being more about research than gatekeeping. I keep thinking that the name Skeptical Science describes the charter.           

    I am skeptical that ENSO is chaotic.
    I am skeptical that ENSO is random.
    I am skeptical that ENSO is triggered by a change in prevailing winds. 

    I think I get it — the skepticism is directed not at current models of bleeding edge climate science where millions of $$ are being poured into machine learning for ENSO predictions by the likes of Google and NVIDIA, but at skepticism to combat crackpot models that claim AGW is being generated by subsurface volcanic activity.   

    Cheers. I think I'm good now.

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  35. Paul Pukete. While this website is called its obviously about climate change and so your comments about the causes of ENSO are strictly speaking a bit off topic. You might consider combining commentary on climate change with some comments on the causes of ENSO. People generally like off topic up to a point, as long as its interesting and people are not constantly off topic and clearly pushing personal agendas. I have generally found your comments interesting.

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  36. Yes, this is getting off-topic.  Risking pushing the envelope, all ENSO phases are clearly warming, due to the underlying and overburdening human forcing of climate becoming increasingly pervasive.  Perhaps a better thread can be suggested for such (but not here).

    All ENSO phases are warming

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  37. Daniel Bailey,

    John Mason @31 pointed to the SkS Argument/Myth item "Global warming and the El Niño Southern Oscillation".

    That does appear to be a good location for the discussion in question to be continued.

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  38. Hi Daniel,

    I like yor graphic.  It appears to my eyecrometer that the line for the La Nina years has too low a slope for the data points.  Did you arrange the graph or did you copy it somwhere?  If the La Nina line is corrected the slope of all three lines is about the same.  We would expect the slope to be the same if the El Nino oscellation was not affecting the underlying AGW.

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  39. Paul Pukite:

    When we discuss new science at SkS we like the contributors to post links to suppoort their positions.  I note that your post at 34 contains several completely unsupported assertions.  Perhaps you could present some data and links to papers to support your claims.  I really do not care what someone who incorrectly labels their graphs thinks.

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  40. @michael sweet @38

    The graphic uses the GISS temperature data, color-coded by ENSO phase, updated through the end of 2021. When the full-year data for 2023 comes out, it should get updated then. The slopes will change somewhat as the background phase states change, but the underlying exogenous driver is still human activities.  As a result, ocean heat content rates are accelerating (from Li et al 2023, Figure 1), further warming all ENSO phases over time:

    OHC is accelerating

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  41. "I note that your post at 34 contains several completely unsupported assertions."

    No problem. Concerning the points that ENSO is not chaotic, not random, and not driven by wind, there are a couple of citations I can point to. The most comprehensive is a monograph that I co-authored titled Mathematical Geoenergy  (Wiley/AGU, 2018, chapter 12: Wave Energy) . Another coincidental finding was reported Lin & Qian "Switch Between El Nino and La Nina is Caused by Subsurface Ocean Waves Likely Driven by Lunar Tidal Forcing"

    These of course havee nothing to do with climate change, as according to the definitions at this site, ENSO is apparently not considered climate change, but as climate variability. 

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  42. Daniel,

    I have seen similar graphs before.  The slopes of the lines are very similar.

    In your graphic the graphed line for the La Nina data is obviously incorrect.  It has a different slope and runs through the middle of the bars when it should be at the top of the bars.  The data is fine.  Hopefully the person who maintains the graph will notice when they add the data for 2023 and correct it.

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  43. Paul Pukite:

    So a monograph that I cannot access and a paper with 21 citations.  Not very impressive.  How well did the group that published the paper predict in advance the last 5 years of La Ninas and the current El Nino?  I am always skeptical of claims that tidal forces can cause changes in weather a year later.  

    It appears to me that the general description that ENSO is random and not predictable in advance is correct.  Your claims at post 34 do not hold up to close inspection.  You are welcome to believe anything you like.

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  44. Regarding the discussion of ENSO patterns, modelling and forecasting.

    The SkS Argument/Myth item "Global warming and the El Niño Southern Oscillation" that John Mason @31 suggested as a more appropriate thread has some potentially very relevant points made in the latest comments starting with comment 198 (from 2019).

    Another location of potentially helpful information is the Australian Bureau of Meteorology's "Climate Driver Update" website (linked here). The "Pacific Ocean" tab (linked here) presents a broad range of forecasts for the NINO3.4 SST from multiple forecasters. There is approximately a 1.0 degrees C range of forecasts for January 2024.


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  45. You may be skeptical of the claims, but they're out there and after 5 years no-one has tried to refute, debunk, or falsify the claims.  I submitted a presentation to next spring's US CliVar Workshop which they're calling "Confronting Earth System Model Trends with Observations: The Good, the Bad, and the Ugly".

    Comparing historical trends in Earth system models with observations to identify and understand where models are performing well and poorly to focus the community on where more work is needed to ensure credible projections moving forward. What are we getting right? What are we getting wrong and why? What have we not yet paid enough attention to and where might surprises lie?

    For over 40 years, and through several rounds of IPCC reports, the climate science community has made projections of climate change under specific emissions scenarios. While assessments of the fidelity of Earth System Model simulations over the historical period have been performed for basic variables such as near surface air temperature, internal variability and a relatively small signal in a short observational record has made a comprehensive assessment challenging.

    My submitted abstract addresses the internal variability part. I don't know yet whether it was accepted for presentation, but I'm confident that it won't be wasting anyone's time. 

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