New paper: How much of the global temperature change is natural?

Holocene century-on-century changes have a standard deviation close to 1deg C, so if there is a signal due to carbon dioxide, it still has not emerged from the background noise

diceGuest essay by Philip Lloyd

A paper of mine has just appeared in Energy and Environment:

(Lloyd, Philip J. An estimate of the centennial variability of global temperatures.  Energy & Environment, 26(3), pp. 417–424 2015. DOI: 10.1260/0958-305X.26.3.417

with an abstract:

“There has been widespread investigation of the drivers of changes in global temperatures. However, there has been remarkably little consideration of the magnitude of the changes to be expected over a period of a few decades or even a century. To address this question, the Holocene records from several ice cores up to 8000 years before present were examined. The differences in temperatures between all records which are approximately a century apart were determined, after any trends in the data had been removed. The differences were close to normally distributed. The average standard deviation of temperature over a century was 0.98 ± 0.27 oC.
This suggests that while some portion of the temperature change observed in the 20th century was probably caused by greenhouse gases, there is a strong likelihood that the major portion was due to natural variations. “

I was led to this by a statement from Trenberth et al in AR4 “The standard deviation of the HadCRUT3 annual average temperatures for the globe for 1850 to 2005 shown in Figure 3.6 is 0.24°C. The greatest difference between two consecutive years in the global average since 1901 is 0.29°C between 1976 and 1977, demonstrating the importance of the 0.75°C and 0.74°C temperature increases (the HadCRUT3 linear trend estimates for 1901 to 2005 and 1906 to 2005, respectively) in a centennial time-scale context.”
This can only be regarded as naïve – the standard deviation of annual temperatures cannot indicate much about the standard deviation
over a century.

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176 thoughts on “New paper: How much of the global temperature change is natural?

  1. “This suggests that while some portion of the temperature change observed in the 20th century was probably caused by greenhouse gases, there is a strong likelihood that the major portion was due to natural variations.”

    It seems this statement contradicts the premise of your argument, which is that no measurable temperature change in the 20th century can suggest any unnatural cause until it exceeds 1C.

    • There is no contradiction. Likelyhood of some warming can be 100% and still the signal is undetectable as such.

      • Yep undetectable after a half doubling of the effect of CO2 above 280 ppm. What’s 2X undetectable again, so we can get our bearings on a full doubling ?

        Any other climate parameters where the effect is above the square root of F-all ??

      • Or the warming can be 100% caused by little green aliens or whatever else you might imagine. But it’s all purely theoretical until the warming exceeds the range of natural variability. That’s the claim being made here. Therefore the claim specifically DOES NOT “suggest” any specific cause. If he wanted to make this statement and be consistent with his argument he might as well have written “my guess is that some portion of the temperature change observed in the 20th century was probably caused by greenhouse gases…” That’s why he contradicts himself.

      • “Likelihood” and other fudge words are unscientific terms used to persuade people. That is why the ipcc use it. If it can’t be measured then it remains conjecture only.

      • Bruce Cobb is correct.

        In science, data is essential. Measurements are data. But there are no measurements quantifying what the fraction of AGW might be, out of total global warming from all sources.

        If any of the rise in temperature is man-made, there are still no measurements quantifying that putative fraction. Thus, man-made global warming is ipso facto a conjecture.

    • Philip Lloyd – Thanks for notifying us of your paper, but regrettably I have to disagree with a part of it – or at the very least seriously question. You say “[..] This suggests that while some portion of the temperature change observed in the 20th century was probably caused by greenhouse gases [..]“. The part before “This suggests” did not appear to me to contain or imply any such suggestion. Where in your data was there any suggestion that greenhouse gases changed in their effect at all? As I read it, you did not address the effect of greenhouse gases, and you did not find any temperature changes that indicated greenhouse gases having any changed effect. I therefore don’t see how you can justify the bit that I highlighted.

      • I regarded that statement on GHG attribution as an obeisance to the CC dogma gatekeepers to get published. Nothing more.

      • This is the problem with just about ALL so called “climate science”. The Data address one thing or the other …. but they almost NEVER address any effect of GHGs. … HOWEVER .. in almost every case, and probably the main driver behind the inclusion of “GHGs caused the recent warming” in papers, the inclusion of a mere sentence, pure op-ed, leads to the perception that there is some sort of consensus that GHGs are significant at all.

        I’d like to see someone do a paper on such. If I had the time, and the personal fortune, I’d do a Medical Style assessment on climate research, where you look at the data, and line up the conclusions. I can almost guarantee that in “97%” of the cases, the data say nothing about GHGs induced global warming, but the sentence “due to climate change” will be included.

      • When I was in grad school many years ago, casually chatting with professors about “publish or perish” and obtaining grants, one made a statement that if the current fad or government interest was in “black squirrels” then anyone with any brains automatically changes their paper subject and conclusions to include SOME mention of “black squirrels.” So, for example, if you want to study, say, radon levels in homes, your grant proposal becomes a study on radon levels in homes and it’s possible effects on black squirrels. And then even if your paper has nothing in it to speak of about black squirrels (other than the inclusion in the title of course), by gawd your paper conclusions tag on a line something like: and therefor it’s suspected that the radon levels detected may also affect black squirrels…. more research is needed to quantify this effect. Or something along those lines anyhow.

        I think we see the black squirrel effect applied very liberally to most papers even remotely related to “climate change.”

    • @Will Nitschke, @Mike Jonas

      The crucial word you both are missing is “while”.

      While some warming might have been (or not) caused by X, Y, or Z, the data suggests that there is a strong likelihood that the major portion was due to natural variations.

    • Right.
      So, Phillip, please explain the GHE in the light of Plancks Laws and the Laws of Thermodynamocs. Both are clear that the GHE is impossible. ie., heat can only travel from hot to cold. The reverse is impossible.

      • John I suggest you include the word “spontaneous” when saying anything about the direction of heat flow.

        Graphicconception microwave ovens do not transfer “heat” and without your intervention of plugging it in and pushing a button nothing happens. In fact there are things that you can put in a micro wave oven and they will not get warmer as they do not absorb the emissions of the cyclotron.

        WPeszko reducing the rate of cooling is not transferring heat. Insulation.

      • Radiation flows out from any object that is above 0K. It flows to all other objects in line of sight, regardless of the temperature of the other objects.

      • mkelly, radiating objects do not transfer heat, they radiate it, which is graphicconception’s point.
        So called greenhouse gases work by radiation, not conduction.

      • MarkW then he is wrong in his example. As you are in your explanation of what he said.

      • mkelly,

        There’s no cyclotron in a microwave oven. It’s a magnetron which produces microwaves (electro-magnetic radiation), cyclotrons accelerate charged particles.

      • Let go of this naive understanding of thermodynamics. If work is done in the process, you can move from cold to hot making the cold colder and the hot hotter – the refrigeration cycle. Yes, it does occur naturally in the atmosphere, too. Simply when warm winds rise up one side of a mountain they cool by expansion (adiabatically). They don’t have to wait for conduction from the colder surroundings at the mountain top. When this cool air flows rapidly down the other side, the reverse happens. It (Chinook winds) compress and heats up solely from this process with no need for added heat to the cold initiating air. Chinooks have caused temperature in mid winter in Alberta to jump 40C.

        “The greatest recorded temperature change in 24 hours was caused by Chinook winds on January 15, 1972, in Loma, Montana; the temperature rose from -48 to 9 °C (-54 to 48 °F).”

        http://en.wikipedia.org/wiki/Chinook_wind

        Adiabatic behavior is, indeed, the first think you will have learned in thermodynamics to get you started. Refresh your knowledge on this pivotal concept. PV=nRT

      • At Gary Pierce.

        Well I believe that Chinook winds simply replace pre-existing cold air with pre-existing hot air; so that is not a Temperature change, that is a location change. The hot air simply moved to where the cold air had been.

        So it is simply convection, which is what winds are.

      • mkelly, you can believe whatever you want. However that doesn’t make your beliefs rational.

    • If I were preparing Lloyd as an expert witness for trial, I’d have to ask him the obvious question ‘Don’t you mean just that: “This suggests that there is a strong likelihood that the major portion was due to natural causes?”

      He should stop there at that conclusion. Why add that the evidence suggests there is some warming ‘probably due to greenhouse gases?’ There is nothing else, no evidence shown anyway, that can be gleaned from his paper about historical temperature deviations that supports the conclusion that greenhouse gases probably causing additional warming, or if so, he should be prepared to identify on cross examination those portions in the report that support such an additional conclusion. I don’t see the evidence there myself for the extra statement. Otherwise, the conclusion that any heat is “probably” (instead of ‘might have been’) caused by greenhouse gases” is extraneous, almost gratuitous, there in a conclusion for another purpose. What could that other purpose be?

    • The differences were close to normally distributed. The average standard deviation of temperature over a century was 0.98 ± 0.27 oC.
      =====================
      99.7% of natural variability will lie within +/- 3 standard deviations. Thus, a change of average temperature as much as +/- 3C per century is within the bounds of natural variability.

  2. This can only be regarded as naïve – the standard deviation of annual temperatures cannot indicate much about the standard deviation.

    It was not naive. It was “convenient.” As in, Purposeful. A willfull adherence, with a heavy dose of cognitive bias, to a dogma that required temp rise of the 80s-90s be anthropogenic CO2, to support the models, rather than vice versa. That in a nutshell defines the pseudoscience that the IPCC (and Trenberth) now wear to call anyone who disagrees with them “blasphemers” (aka, d*niers of the orthodoxy).

  3. With roughly 30% of all manmade CO2 emissions since 1750 being emitted over just the last 19 years, with virtually no global warming trend observed over the past 19 years to show for it, it’s becoming painfully obvious global temperatures are much less sensitive to CO2 than CAGW hypothesizes.

    Dr. Lindzen and other scientists suggest CO2’s contribution to total global warming since the end of the Little Ice age could be as little as 0.2C, which is consistent with “The Pause” observed for almost two decades…

    The longer “The Pause” continues, despite record annual manmade CO2 emissions, the higher the probability CAGW is a busted hypothesis.

    Observed satellite temperatures are already 2+ SDs below CAGW model-mean projections, and could well be 3+ SDs off in 5~7 years if current trends continue…

    CAGW is on the cusp of being laughed and eye-rolled into oblivion.. None of CAGW’s dire predictions are coming even close to reflecting reality, so if the Scientific Method is still the measure of science, CAGW’s days are numbered…

    CAGW adocates are quickly running out of excuses and time to explain why their hypothesis has failed so miserably for such a long duration.

    • From Samurai:
      “Observed satellite temperatures are already 2+ SDs below CAGW model-mean projections, and could well be 3+ SDs off in 5~7 years if current trends continue…”

      The snake is biting it’s own tail. The alarmists chose, quite deliberately, to include hopelessly and demonstrably wrong climate models in their “model mean” numbers for the single reason of getting a high average number.

      They practised to deceive. Now, saddled with an alarming model mean, the pause, much sooner than it should have, caused the problem you describe so clearly. The only reason the temperature will be three standard deviations away from the model mean is because they chose such a silly number to begin with.

      It is no longer possible to claim the temp is still within an expectable envelope. They saddled themselves with the hockey stick, and now they are getting beaten with it.

      Everyone but everyone knows the high models are ridiculous. The IPCC only clings to them because it brings up the model mean. The lowest projections are probably reasonable but not in the slightest alarming. The pause is well within the envelope of reasonable models, but the model mean of the whole suite doesn’t allow them to use that lower value as a founding argument. They are stuck with the artificially and baselessly inflated number, provided in part by the relentless Canadian environment service which funds the second worst ‘prediction’ of all. Now their own number bites them in the ass.

  4. Pretty much, but why stop at 8000 years? The hollowscene ain’t nuttin’ but another interglacial. Proxy indications of the entire range of earth temperature range from 7 to 20 deg. C. We have no explanation for any of this variance. Error bars are a joke. The only factor we can reasonably exclude is Carbon dioxide.

  5. Lets look at the run up in T since 1979. (The Ice Age scare https://stevengoddard.wordpress.com/1970s-ice-age-scare/ endorsed by most every scientific body at the time) https://bobtisdale.files.wordpress.com/2015/04/figure-24.png

    So we look at a smidge below -.2 C in 1979. And we look 2015 and see a smidge below plus .2 C, for a total increase of .4 c in 36 years. However we notice the trend line pulled down a bit by two volcanic events, and the the large step change up in 1998. During this time we did have a “Super El Nino, and we did have a positive AMO, with a very strong correlation to NH T.

    Hadcrut 4 showing a smidge under .4 degree drop from the 40s high. If the reverse were to happen, a “super la Nina”, and a strongly negative AMO, what would the GT be? Could it erase the warming since 1979???

    • The point about these plots is that it is glaringly obvious that there is no straight line linear trend.

      It is the use of a straight line linear trend (when the data shows something rather different) that has got ‘climate science’ into such a mess.

      The fact is that there is no first order correlation between temperature and CO2 in any of the temp data series. The satellite data in particular makes it clear that there is simply a one off step change in temperature in and around the Super El Nino which event was almost certainly natural in origin and released a large amount of heat in the atmosphere.

      What is not understood is why the temperature released in the 1998 Super El Nino has not dissipated/is taking so long to dissipate (depending how the ‘pause’ pans out).

      Presently all one can say about climate sensitivity is that if there is such a thing we cannot measure the signal to CO2 over and above the noise of natural variation using our best temperature measuring devices. this may suggest that climate sensitivity is very low, however, I consider that there are wide error bounds to the various temperature data sets and given these wide error bounds, it is conceivable that climate sensitivity could be quite large (may be even as large as 1degC per doubling).

      But as matters presently stand one is forced to conclude that there is no firm evidence (ie., evidence that withstands ordinary scientific rigour) that suggests that in real world conditions of Earth’s atmoosphere that CO2 does anything to control temperature such that it is likely that climate sensitivity, if any at all, is modest to non existent.

      Of course, on top of that, in the proxy record, there is evidence that CO2 lags temperature and is a response not a driver of change. .

    • UKMO-CRU, NASA/GISS, NOAA/NCDC can do all the temp data fudging homogenization, cherrypicking, infilling they want. But nature doesn’t care. The polar sea ice levels have too many eyes on it to fudge. The agricultural productivity of the world has too many eyes on it. Local high low temp records are too many to refute when heat waves fail to materialize when cold spells abound. Tropical storms, same; too many eyes for them to fudge everything. Reality is bee-yotch slapping the climate change liars pretty regularly now.

      The climate change modellers have done all they can with their grasp of reality. They’ve built their fake runways, bamboo control towers, manned with natives wearing the latest coconut model headsets… and still the airplanes don’t land and the global temps don’t move lockstep upward. Everything is right, but something terribly fundamental eludes their grasp.

      • Quite so, if nature does not play ball.

        However, the warmists always rely upon an El Nino and are no doubt praying for a large one in the run up to Paris. If it pans out that way, it will not matter that there may be a La Nina in 2016/7 which brings down the anomaly and which by then extents the ‘pause’ to over 20 years. The only saving grace is that unless a lot of money is on the table, there is no way that China or India will play ball, and hopefully Australia and Canada will be luke warm and this may encourage a certain amount of realism that a deal to screw the West/Developed NAtions cannot be struck.

      • Wayne I agree with you. BUT these two science academies and KT, Solomons etc are supposed to be the best.
        It’s okay to claim it’s all BS, but how do they always get a free pass? Surely there must be a journo somewhere who would call them to account for their BS?

    • I work in the telecom and television industry, the number of journalists that will or can tackle an issue of any complexity are very few and far between, and the number of journalists that have the substantive knowledge to take on a subject like this probably numbers in the “zeros.” Most journalists, (sic), are just looking for a story that will compete with other stories for web page space or on-air-time, so they go with the most outrageous narratives, like Hansen’s and Mann’s, because that makes for a more splashy headline.

      • Most “journalist make up what they write, God forbid they do research, they have a dead line to met, they can’t do any damn research! Add on to it they were the C & D students to begin with is it any wonder they can’t get anything right!

  6. @Hugh

    …There is no contradiction. Likelyhood of some warming can be 100% and still the signal is undetectable as such….

    There are some delicate nuances of language going on.

    English is a very ambiguous language, and meanings can be varied subtly (or radically!) by changing the placement of clauses in a sentence.

    …This suggests that while some portion of the temperature change observed in the 20th century was probably caused by greenhouse gases, there is a strong likelihood that the major portion was due to natural variations. “…

    In this case, putting ‘This suggests’ at the front of the sentence means that it governs the ideas following it – so the finding of 0.98+/-0.27 ‘suggests’ both that some portion is anthropic and some portion is natural. Which is not really the case.

    It would have been better to say that:

    …While some portion of the temperature change observed in the 20th century was probably caused by greenhouse gases, this suggests that there is a strong likelihood that the major portion was due to natural variations. “…

    • There is no doubt that in my mind the sentence is ambiguous, and possibly contradictory. It was no doubt deliberately framed in that manner. Possibly because with proxy evidence/data there are always large margins of error. Does anyone really consider that it is possible to conclude a trend +/- 0.27degC with proxy evidence?

      That said, the final quoted sentence is an over extrapolation of the point made in the paragraph concluding: “…The differences were close to normally distributed. The average standard deviation of temperature over a century was 0.98 ± 0.27 oC.”

    • And we have politicians to thank for what is called “modern” English (UK). It’s no wonder we can say the same thing in so many different ways.

      • Indeed so. And is why so many other cultures are adopting “American English” because it says, what it says, on the can. But English English is like this…

  7. This paper makes an important distinction, which papers like Markot, Shake’n’Mix willfully ignore: you cannot compare variability in data with a sampling frequency often measured in centuries or even millenia from ice cores and other proxies with the variability in annual or monthly ‘anomalies’.

    The interannual variability is about twice the interdecadal variability ( and both are very similar to temperature changes )
    https://climategrog.wordpress.com/?attachment_id=233

    It is probably that centennial change is even less: it’s the integrating effect OHC

    A centennial change of 0.7 deg C in SST is not alarming. What appeared alarming in late 1990s was the rapid uptick. But now Richard Betts of UK Met Office has just told us that this was understood and largely predicted. ( Though that is the first time I’ve heard that said ).

    Kudos to Philip Lloyd for getting this published.

      • The correlation is clear. There is no credible case for claiming that changes in CO2 cause changes in SST. Plenty of evidence that SST is the cause and CO2 the effect.

      • Mike , thank you for the plot. I expect many readers here have observed the fact that the current pause in the rate of ground temperature rise is coincident with the linearity of the CO2 concentration increase , ie dT/dt ->0 as d2CO2/dt2 -> 0 but have not seen it so elegantly demonstrated .. The problem is why is there such a dependence.?
        I looked in a standard textbook , RM Goody’s 1995 edition of “principles of AtmosphericPhysics and Chemistry ” and tried playing with the simple equations in Para 5.3.2. The only way I could get linearity of dT/dt is by situation where the optical density of CO2 is vanishingly small compared to that of H2O . This contrary to observation , so is ruled out. There must be another CO2 related function but I have no clue what that might be.
        I wonder if the Monckton equation is compliant with your graph?

      • There are lots of charts available that show ∆T is the cause of ∆CO2. Here is one of many I have saved.

        But I have never found a similar chart showing that changes in CO2 cause subsequent changes in temperature.

      • dbstealey , thank you for your reply . Since I failed to reconcile Mike’s plot with the standard forcing theory as given by , for example, Goody , it leads to the reluctant conclusion that the standard theory is either incorrect , or , more probably , much exaggerated .
        However this leads me to conflict with the theories and conclusions of scientists whose hems I am not worthy to touch so I am somewhat apprehensive in concluding that increase in CO2 follows rather than leads increase in temperature . However at present I see no alternative , which means that the standard radiative transfer theory needs reinvestigation . So who is going to do that?

    • Mike said:
      “What appeared alarming in late 1990s was the rapid uptick. But now Richard Betts of UK Met Office has just told us that this was understood and largely predicted.”

      I would like to know how they could have predicted the AMO and Arctic warming from the mid 1990’s, especially as increased forcing of the climate should have reduced that warming by increasing positive NAO/AO conditions.

  8. Still seems that science wanders within their lack of understanding of the natural law. How much time and money spent so far. we could have another one of our globe to buy somewhere in the universe. All this is happening in the form of clear and unclear processes that conform to natural laws, it is the result of mutual relations of celestial bodies in the solar system. Measurements and theories will never lead to a true knowledge of the causes of any phenomenon. It must be understood that we are formed within all these events in the universe, only we have the desire to be above it all and that we are the main factors in these changes, which is a big misconception.
    First, the focus should be the origin of matter and all its associated properties. The most important thing is to figure out the concept and the formation of gravity, magnetism, electrical charge and the movement of matter. All manifestations of the heavenly bodies are the consequences of mutual relations of these major properties of matter. This applies to all the planets and celestial bodies in the entire universe. Our influence in such global changes in nature is absolutely unimportant. Our actions can cause some local changes, but that we warm up the planet by some cycles, which some attribute to our activity, it is absurd.
    Focus on the effects of the mutual effects of magnetic fields that are “occupied” by those elements in movement that change their electrical charge. Therein lies the secret of all phenomena that modern science or not, or does not know to understand

      • We will not wait too long, I guess someone will realize that this is just a contest who will more nonsense to publish about this enigma. I will mention that this planet, but 4 of them are “organizers consensus” sunspot cycle of about 11.2 years, which are only indicators of what will happen. And what will happen depends on the intensity of the resultant impact of these planets to the sun. There are other many cycles which can be set for all time, in my, not theory, but the evidence (mathematics, astronomy, diagrams, etc.). I expect assistance programs, if any some interest.
        I think these discussions useful, inasmuch as it is a lot of real relevance to the issue, but it’s out of the line leading to the true causes of the phenomenon.

      • Thank twice: first, that there is someone who has similar views and perhaps prove that in the near future to come to the fore and, secondly, as a simple, but very precise way of giving your opinion.

  9. If global temperatures refuse to rise as models predict, high natural variability can rescue the models. Just define natural variability as the difference between the model and the observations and your model will always be fine. As long as there is some warming, however slight, you can pick any climate sensitivity you’d like and human caused warming can be said to dominant. For instance, if your model says that it should warm 5C over a century, but in reality temperatures only increase by 1C, then find 4C natural variation (cooling), and since 5C is more than 4C, human influence is still dominant.

    • Steiner– I’m sure the CAGW advocates will try to blame natural variability on the lack of CO2 induced warming for almost 2 decades, however, they can’t have their cake and heat it, too.

      If, for example, they claim decreasing sunspot activity is the natural variable causing “The Pause”/cooling, then they logically have to admit that the strongest 63-yr string (1933~1996) of solar cycles in 11,400 years was the primary cause for 20th century’s 0.8C of warming; not CO2…

      If they don’t do this, it’s completely impossible to explain why their hypothesis and climate models, which assume strong CO2 sensitity, don’t work…

      Humans are breaking annual CO2 emissions records every year, with absolutely no global warming to show for it for almost two decades….

      The CAGW: assumptions, math, physics, statistics, models, projections, etc., are completely falling apart and the longer these huge discrepancies exist, the higher the probability CAGW is a failed hypothesis.

      • “If, for example, they claim decreasing sunspot activity is the natural variable causing “The Pause”/cooling, then they logically have to admit that the strongest 63-yr string (1933~1996) of solar cycles in 11,400 years was the primary cause for 20th century’s 0.8C of warming; not CO2…

        I don’t think they have to admit anything. They are doing government science and they are paid in many different ways to deliver the message that CO2 control is absolutely necessary. They are peddling myth not science, so they will twist logic into a pretzel as the need arises.

      • Samurai, you are completely correct in principle, but let’s get the numbers right. When you run the numbers, the modern maximum in solar activity includes the SC23 peak years. Using whole cycles isn’t necessary.

        Using SIDC sunspot numbers, for the 68 years from 1936-2003, in terms of sunspot activity, the Sun had 89% more activity than the previous 68 years,1868-1935, (annual SSN of 76 vs 40.2). Using Dr. Svalgaard’s preliminary revised SSNs from 2014 (to be finalized in August), the disparity was 71.7% (73.5 vs 42.8).

        The Sun caused global warming!

        The ‘pause’ is the Earth’s cooling response to overall much less solar activity since 2003. Therefore,

        The cause of the ‘pause’ was the cause before the ‘pause’!

        That is too simple of an explanation for many, so they mistakenly try making it more complicated than it is.

        Agreed: “CAGW is a failed hypothesis”.

  10. The assertion that 75% of the warming in that last 50 years was due to a natural cause (it’s the sun) did not get traction when there was 18 years without warming.

    18 years without warming might be a pause, a hiatus in a warming trend.

    Do you think in your face cooling could change people’s minds?

    https://wattsupwiththat.files.wordpress.com/2012/09/davis-and-taylor-wuwt-submission.pdf

    Davis and Taylor: “Does the current global warming signal reflect a natural cycle”

    …We found 342 natural warming events (NWEs) corresponding to this definition, distributed over the past 250,000 years …. …. The 342 NWEs contained in the Vostok ice core record are divided into low-rate warming events (LRWEs; < 0.74oC/century) and high rate warming events (HRWEs; ≥ 0.74oC /century) (Figure). … …. "Recent Antarctic Peninsula warming relative to Holocene climate and ice – shelf history" and authored by Robert Mulvaney and colleagues of the British Antarctic Survey ( Nature , 2012, doi:10.1038/nature11391),reports two recent natural warming cycles, one around 1500 AD and another around 400 AD, measured from isotope (deuterium) concentrations in ice cores bored adjacent to recent breaks in the ice shelf in northeast Antarctica. ….

    I wonder what caused cyclic warming and cooling on the Greenland Ice sheet in the past? Curious that the same periodicity (time between events, 1500 years with a beat of +/- 400 years) between all warming and cooling events/cycles (including the massive ‘Heinrich’ Event is the same (same periodicity, same forcing function). It is also really weird that the warming and cooling periodicity is observed in both hemisphere.

    Greenland ice temperature, last 11,000 years determined from ice core analysis, Richard Alley’s paper. William: As this graph indicates the Greenland Ice data shows that have been 9 warming and cooling periods in the last 11,000 years.

    Everyone of course is aware that there is now above normal total sea ice (sum of sea ice both poles). There is record sea ice in the Antarctic every month of the year and the Arctic sea ice is recovering.

    Snowfall is above average on the Greenland Ice sheet.
    Greenland Ice is cooling which is interesting, as the Greenland Ice sheet has ground zero in terms of amount of warming in the last 30 years.

    Checkout the lack of melting on the Greenland Ice sheet.
    http://beta.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/

  11. Unfortunately I can’t see the whole article but two things puzzle me.

    1. What is this concept of “average SD”? Which values of SD were taken in order to create this average?

    2 .Normally if something is within +/- 3SD of the average we would consider it to be explainable by natural variation. This would imply temperatures could vary by up to almost 3’C before we would need to invoke AGW, and I’ve never heard anyone say that. If the SD of temperature is so large then this whole AGW thing would never have got off the ground in the first place…. would it?

    • Simple; add up all your SDs, and divide that sum by the number of SDs. There; that’s your average SD.

      What it means ??

      Nothing; it’s just something defined that way, in statistical mathematics.

  12. As a geoligist, I regard man (both sexes) as part of nature, therefore even climate change attributed to man is by definition “natural”. It is only religious types who consider man (both sexes) as “not part of nature” and who therefore can consider some climate change as “unnatural”. I believe it is really significant to identify those people who do not consider themeselves as part of nature because it is always those people who want to control nature by controlling other people.

    • I am a religious type and consider man a part of nature. I don’t think it’s necessary to generalize and lump us religious types all together. More specifically the point is about if our ommissions of C02 that we choose to put in the atmosphere are warming the planet or not. Religion has nothing to do with it. If anything religions people are supposed to have faith in a higher being which suggests to me that they wouldn’t be so worried about climate change. You also imply religious types want to control people and that is an unfair generalization that is not true of every religious type.

      • Izzat omissions or emissions ? Omitting and emitting are sort of at cross purposes.

      • Not implying any judgment; but what types of religions don’t make any attempt to control the behavior of their adherents. Some even want to control the behavior of non adherents; to the point of wanting to kill non compliers ( and actually doing that ) , mohammedans for example ?

    • I agree with Victoria it is not religious types, it is specifically the green religion that has morphed into a warped ideology of man separate from nature and harmful, injurious, detrimental, deleterious, damaging, hurtful, destructive, and ruinous to nature..

    • Well the SD doesn’t really have any quantitative meaning except for data sets that exhibit a normal distribution of values.

      And then it only separates cases closer to the mean from cases further from the mean. And remember the exact values of all data set items are known; so the SD doesn’t tell you anything that you didn’t already know.

  13. “This suggests that while some portion of the temperature change observed in the 20th century was probably caused by greenhouse gases, there is a strong likelihood that the major portion was due to natural variations.” joelobryan said “I regarded that statement on GHG attribution as an obeisance to the CC dogma gatekeepers to get published. Nothing more.” Indeed, it was a sop to a reviewer – was I arguing with the physics that said carbon dioxide had to contribute to the warming? I responded that the Big Question was not whether is contributed, but how much, and eventually we agreed on the text.

    • ” … was I arguing with the physics that said carbon dioxide had to contribute to the warming? I responded that the Big Question was not whether is contributed, but how much, and eventually we agreed on the text.”

      Most understandable Dr. Lloyd. Even here at this site, one can not argue that CO2 does not contribute to the warming of the surface of the planet. One may argue that CO2 contributes very little. So, you did the same sort of thing to get the paper published. Understandable.

      • One can not argue, with scientific evidence to back up ones’ argument either way. The warming effect, however small, remains conjecture.

      • Bruce, there are those of us who would argue that we can, indeed, prove that CO2 does not warm the surface. However, that argument is not allowed here. See site policy.

      • To sum up:

        Catastrophic: No evidence and abundant evidence to the contrary.

        Man-made: Effects on “climate” observed locally, as in the UHI effect.

        Global: Little to no evidence globally, but see above.

        Warming: Even the sign of any human effect can’t be known, ie whether the net effect of human activity is to warm or cool the air. But even if it’s to warm, so far that has been a good thing, however negligible, as has increased CO2 itself.

        Climate Change: Of course. Earth’s climate has been everything from covered with a global ocean of molten rock to same of water ice, and everything in between.

      • No event has ever happened twice; that would be a different event.

        Ergo climate must change, since it cannot repeat.

  14. Philip Lloyd

    I read your paper with interest and I accept its main conclusion. But I write to request your comment on a possible criticism of the paper.

    This thread has included much discussion of a single sentence in the paper’s abstract. But there has not been much debate about an underlying assumption used in the analysis the paper reports.

    The analysis was of temperatures indicated by proxy data from four ice cores (i.e. GISP, GISP-2, Vostock and Dome-C).

    The paper’s conclusion includes

    the best estimate of the centennial standard deviation of temperature during the Holocene is 0.98 ± 0.27°C.
    During the 20th century, thermometers recorded an increase of about 0.7°C.

    This begs the question as to whether it is valid to compare the proxy indications from ice cores to the increase that “thermometers recorded”.

    If that comparison is not valid then it is reasonable to challenge the paper’s major conclusion ; viz.

    The signal of anthropogenic global warming may not yet have emerged from the natural background.

    Richard

    • Richard – one thing the ice cores do well is record temperature CHANGE. The end of the last ice age is clearly shown in many cores, and both the rate of change and its timing are similar. They don’t however, do a very good job on absolute temperatures, so comparison with thermometer records is dubious. I was primarily interested in change, for which they seem to do quite a reasonable job.

      • Philip Lloyd

        Thankyou for your reply.

        I stress that I agree your conclusion and your reply to me. However, they could both be questioned by doubters who could have difficulty equating your admitting the ice cores have problems indicating “absolute temperatures” and your comparison of “centennial standard deviation of temperature” with “During the 20th century, thermometers recorded an increase of about 0.7°C”.

        I am trying to be helpful.

        Richard

  15. There is yet another problem.

    When you zoom in closely on ice core isotope temperatures and temperatures derived from other biologic proxies there are often mismatches, for instance: http://www.geol.lu.se/personal/seb/Geology.pdf.pdf

    So if you look at the water cycle, isotope ratios in precipitation depend on two main factors, temperature during condensation at the source of the precipitation and raining out (Raleigh fractination) out on the path to the destination http://courses.washington.edu/proxies/AirTemp_2.pdf

    However temperature during condensation is the effective dewpoint at the sourec location, which is much less dependent on source temperature but much more on absolute humidity.

    And there is also the seasonal precipitation ratios that average out over the year. Wet summers or dry winters making the average precipation isotope mix “warmer” and vice versa. A combination of both effect explains the deviation that Bjorck et al 2002 -previous link- observe

    ice core isotope thermometer are considered the gold standard however there are many complications challenging its reliability.

    • Just select a number of suitably conflicting proxy records average them and the inconvenient Holocene Optimum goes away not to discombobulate the true believers ever more:

      “During the Holocene itself, there is general scientific agreement that temperatures on the average have been quite stable compared to fluctuations during the preceding glacial period. The above average curve supports this belief. However, there is a slightly warmer period in the middle which might be identified with the proposed Holocene climatic optimum. The magnitude and nature of this warm event is disputed, and it may have been largely limited to high northern latitudes” (Wiki).
      Next up the Eemian.

    • However temperature during condensation is the effective dewpoint at the sourec location, which is much less dependent on source temperature but much more on absolute humidity.

      It depends on the relative humidity. That’s why we measure and report it.

      • No, It’s the dewpoint is predominantly a function of the amount of water vapor per volume and a little bit a function of the total pressure. That’s what determines the isotopes ratio at the moment of condensation. The initial ambient temperature of that air parcel at ground level is not relevant. If it’s relatively warm, it will take longer during ascend before condensation takes place.

        For instance if you take a standard emagram http://en.wikipedia.org/wiki/Emagram

        I made an example here:

        you’d see that an rising air parcel starting with a temperature of 20°C and a dewpoint of 15°C (RH 73%) will start condensation in the lower blue circle at about 14°C at around a pressure around 920 Hpa

        We also see that a rising air parcel of 30°C and a dewpoint of about 17°C (RH 46%) will start condensating again at 14°C in the upper blue circle.

        But in both cases the ice cores get the same initial isotope signature that goes with a condensation at 14°C, however the real source could just as easily have been 20°C or 30°C. So, that’s the essential problem for ice cores. They register local dewpoint (like 14°C here in this example), not the ambient temperature.

  16. The North Atlantic SST or its de-trended version Atlantic Multidecadal Oscillation–the AMO is the best known and likely to be most representative exponent of the climate’s natural variability.
    The record could be split into two sections 60 years apart, 1860s-1950s and 1920s-2010s From 1860 to 2014 overall warming is about ¼ degrees C/century, and curiously also repeated by each section individually, while the 30 years min/max differential in each section is about 0.4C. This would imply a self-sustained natural oscillation.

    This 60 years repeatability is ‘augmented’ by 0.2C temperature jump between sections, which it could be due to number of factors ranging from another longer term underlining natural process or simply the ‘anthropogenic’ data adjustment but
    It is not possible to reconcile with the CO2 rise, whenever from 1860 to 2014, the CO2 effective starting point is taken.
    Since TSI or other sources of energy have not the required variability, the most likely case is that the temperature variability is result of the available energy redistribution across the region, i.e. more equatorial heat content is moved pole-ward and less radiated into the space and vice versa.
    This can be archived by alternative increase and reduction either in the volume or velocity (or both) of the Gulf Stream and the North Atlantic Drift current. The SST changes are strongly dependent on circulation and salinity stratification of the upper ocean’s layers. The deep ocean’s influence is a factor reflected in the thermohaline circulation (THC) including the N. Atlantic’s “overturning circulation”.
    More HERE

    • 1. Introduction
      Our previous study showed that the response of tropospheric pressure to variations of solar activity (SA) and
      galactic cosmic ray (GCR) fluxes reveals a regional structure determined by the positions of the main
      climatic atmospheric fronts, as well as it strongly depends on the epochs of the large-scale circulation
      [Veretenenko and Ogurtsov, 2012]. In the epochs of increasing intensity of the meridional circulation (the
      form C according to Vangengeim-Girs classification [Vangengeim, 1952; Girs, 1974]) an increase of GCR
      fluxes at minima of the 11-year cycle is accompanied by an intensification both of extratropical cyclones at
      Polar fronts of middle latitudes and Arctic anticyclones at high latitudes of the Northern hemisphere, as well
      as by a weakening of the equatorial trough at low latitudes. In the epochs of decreasing meridional
      circulation the troposphere response to SA/GCR variations reveals a similar regional structure, i.e., the
      regions of most pronounced effects are closely related to the climatic atmospheric fronts, but the sign of
      SA/GCR effects in these regions is opposite.
      It was also detected [Veretenenko and Ogurtsov, 2012] that the evolution of the meridional circulation
      is characterized by a roughly 60-year periodicity which, in turn, influences the sign of SA/GCR effects on
      troposphere pressure. Indeed, the reversals of the correlations between sea-level pressure at high latitudes
      and sunspot numbers occurred in the 1890s, the early 1920s, 1950s and the early 1980s and coincided well
      with the changes in the evolution of the C-type meridional circulation. Hence, the aim of this work is to
      study what processes may influence the evolution of the large-scale circulation and, then, the character of
      SA/GCR effects on troposphere pressure.
      http://geo.phys.spbu.ru/materials_of_a_conference_2012/STP2012/Veretenenko_%20et_all_Geocosmos2012proceedings.pdf
      1980 plus 30 is the 2010.
      http://woodfortrees.org/graph/esrl-amo/from:1850

      • Let’s see a sharp decline AO in 2010..
        Annual Arctic Oscillation (AO) index values since 1950. Pressure variability for the winter is larger than the annual variability. Following peak values 1988-1093, the AO index have since decreased to values near zero or below. AO data can be downloaded from the NOAA Climate Prediction Center by clicking here. Last update: 7 June 2014.

    • MAVukcevic, the Sun absolutely varied enough to cause the AMO history you depict. Looking at the minimums and where they are in time wrt solar activity, ~1910 and ~1975, both occurred when solar was low, with the recent AMO maximum coinciding well with the Sun’s modern maximum from 1936 to 2003.

      Solar energy accumulates in the oceans when solar flux is above ~120 sfu, and dissipates below that level.

      A complete solar theory must include heat accumulation at depths in the oceans that takes time to make it’s way to the surface. Thus, SSTs are a function of today’s solar output, previous solar output, and circulation.

      • Nonsense, solar forcing of the NAO/AO was very strong through the mid 1970’s when the AMO was at its coldest, and has declined since the mid 1990’s with the AMO warming, because weaker solar wind increases negative NAO/AO:

      • North Atlantic SST can be linked (indirectly) to the solar 22 year cycles in two ways
        They are described HERE and HERE .
        I am not sure that the TSI could do it alone, unless available data is wrong.

      • Ulric, the only nonsense here is that you missed the point.

        I didn’t mention the NAO or AO. I specifically referred to the AMO only.

        In 1975, after SC20 was over, during which time the solar flux averaged 113 sfu/day, the cumulative effect of the lower solar activity from the end of SC19 onward, to that point in time, was the reason temps were at a low point then, after which they responded to higher solar activity levels in SC21, 22 & 23.

        I was talking about solar flux, which you know is not the solar wind. You are comparing apples to oranges.

        Now, that said, you would be well served to explain your mechanism as to how the solar wind affects the NAO/AO.

        Perhaps you could show your enlightenment by describing the relationship(s) between AMO and NAO/AO.

      • Bob, the reason that the global mean surface temperature dropped 1970-76 was the collective negative feedbacks of a cold AMO, increased La Nina, and the associated increase in rainfall across continental interiors.

      • ….which were the Earth’s natural cooling responses to lower solar flux for SC20….

      • Bob said “….which were the Earth’s natural cooling responses to lower solar flux for SC20….”

        La Nina and a cold AMO act as amplified negative feedbacks to increased solar forcing. Global mean surface temperature changes are not directly proportional to forcings, but move inversely to forcings at up to interdecadal scales. I do not recommend that you follow what Piers Corbyn says on this. His forecast for less El Nino through the next 20 years, shows that he doesn’t know the first thing about the direct association of increased negative NAO/AO with increased El Nino, and a warmer AMO.

      • No, for what I think might be reasonable ‘reason’:
        North Pacific in long term appears to be neutral ( east – west: oscillating between warm-cool and cool-warm),
        I don’t think that the global SST data is good enough.

  17. It’s hard to believe these guys are serious. Highly damped ice core data vs thermometers!?

    • Do these “Scientists” realize that when you “average” numbers, data, etc, over a period of time that the resulting graph is shifted by the process of averaging? The smother the graph, the more it is shifted or delayed.

  18. We don’t even understand how human CO2 emissions contribute to total CO2 in the atmosphere. Until we understand this, it is futile to try and predict what effect human CO2 emissions have on temperature.

    • Globally, I would suggest that effect is ZERO. However, land use changes such as deforrestation etc, I would suggest local climate may be effected by human activities and there is evidence to support that. But CO2 (~3% of ~400ppm/v)? Nah!

  19. likelyhood should be evaluated by correlation between cause and effect. A mere time series analysis of one parameter, temperature, cannot explain anything other that … it varies.
    And searching for correlation is not successful. Anything that shows a rising pattern over the observation period may correlate with temperature: sea level, CO2, magnetic field declination. One has to look at Rates of Changes (derivatives) to see that such correlations are terribly bad.
    See this paper: https://hal.archives-ouvertes.fr/hal-01146608

    • I second that motion! The Global temperature of the Earth (if that is at all possible to determine,) has remained closer to the average than the state of the art computer controlled thermostat in the average office building (as they contain auto heat/cooling functions) has over the last year (ignoring any power losses or automatic setbacks.)

  20. There appears to be no correlation between CO2 emissions and climate change. Many warmists believe it is linear ie y=mx+c and it most certainly is not. Extreme warmists (Mann, Gore etc) insist that it is exponential ie y=e^x. Experience over the last 18 years indicates that a flatlining correlation is appropriate ie y=C where c=0

    • Markstoval, agreed. Good question. The average daily climate-relevant number would be the time-weighted temperature factored with the absolute humidity. That would report the energy content average during the period.

      Humidity has a strong effect on temperature. Ultimately the claim about temperature is a claim about energy and the temperature doesn’t tell us the energy content of a system with variable humidity.

    • “Why not use the median?” This is an interesting question.
      In my field of underwater acoustics, the mean is generally higher than the median for many data distributions. Take for example long-tailed distributions of shipping noise vs. azimuth… the mean is at about the 85th %-ile!
      So using the mean may well bias the answer high, and in a somewhat unstable way.

    • The median depends on the number of samples (readings) you take. The average does not.

      So if you average a data set, you always get a value which could actually be equal to one of the data set items.

      With the median value, it can NEVER be equal to one of the members of the data set unless there is always an odd number of set members, and it ALWAYS is equal to one of the set values if there is an odd number of items in the set.

      With the average, it can equal one of the set values but it also might NEVER be equal to any member of the set.

      But both of them are simply algorithms defined in statistical mathematics; they are what they are defined to be.

  21. There is no scientific proof that any changes in Earth’s climate have been caused by humans.
    .
    Since climate change for the past 4.5 billion years has been “natural”, including several ice ages that came and went, there would have to be unusual climate changes in the past century to suggest any meaningful climate effect from humans.
    .
    There have been no meaningful climate changes in the past 100 years of very rough measurements — slight warming or cooling over 100 years is not unusual, proves nothing, and predicts nothing.
    .
    We do know that humans have built many cities, and cities are warmer than the surrounding countryside.
    .
    Since some thermometers used for the global average are located in cities (too many), one could say the increased area of Earth covered by cities is probably responsible for some warming that has been measured by surface thermometers … but that climate change must be one that people like, since so many of them choose to live in cities.
    .
    Climate change today is not science — it is a political tool used by leftists to scare people into wanting more government control of corporations, and their own lives.
    .
    It has been more effective than past boogeymen, such as DDT, acid rain, and the hole in the ozone layer, only because of the huge amount of government funding available for any scientists willing to “cry wolf” in return for grants.
    .
    The average temperature of Earth is a meaningless, inaccurate, statistic used for political purposes by presenting truncated charts that make meaningless 0.1 degree changes in the average temperature look important.
    .
    Sadly, skeptics tend to use the same misleading style of temperature charts, even on this website, when they should know better.
    .
    Climate change for non-scientists here:
    http://www.elOnionBloggle.blogspot.com

    • Be careful you don’t fall into the same trap you are criticizing. Your opening statement:

      There is no scientific proof that any changes in Earth’s climate have been caused by humans.

      conflicts with your later point:

      The average temperature of Earth is a meaningless, inaccurate, statistic used for political purposes by presenting truncated charts that make meaningless 0.1 degree changes in the average temperature look important.

      Your first statement is implicitly based upon a global average since, as you subsequently point out, local and possibly regional climate impacts by human have been demonstrated by valid observations. Yet your opening declaration appears to reject the possibility of local, long-term weather pattern changes as a result of human activity.

  22. For forecasts of the timing and extent of the coming cooling based on the natural solar activity cycles – most importantly the millennial cycle – and using the neutron count and 10Be record as the most useful proxy for solar activity check my blog-post at
    http://climatesense-norpag.blogspot.com/2014/07/climate-forecasting-methods-and-cooling.html
    We are past the 1991 millennial peak in solar “activity” (figs 14 and 13) and 12 years past the corresponding temperature peak in the RSS data in 2003. See
    http://www.woodfortrees.org/plot/rss/from:1980.1/plot/rss/from:1980.1/to:2003.6/trend/plot/rss/from:2003.6/trend
    The general cooling trend will likely continue to the depths of the next LIA at about 2650. This trend will be modulated on the way down by the shorter term temperature periodicities ( De Vries , Gleissberg and 60 year cycles.

    • Dr. Page, while I don’t go as far as 2650, my solar model, which is based on F10.7cm solar flux and SSTs, indicates that we started cooling overall post-2003, as you have determined, and that sometime between this year and 2017, we are going to experience noticeable cooling from lower solar activity (less energy in). My model is NOT based on cycles, but rather actual measured solar activity levels.

      The recent end of 2014/start of 2015 warmth records were driven by higher solar activity since Sept 2014, that has since dropped off.

      The Sun is currently oscillating around ~133 sfu/day (over one rotation). For instance, for the past two weeks, half a solar rotation, F10.7 averaged 144 sfu/day, and for the next two weeks, according to the USAF 45 day forecast, http://services.swpc.noaa.gov/text/45-day-ap-forecast.txt, they say the average will be 106 sfu/day over the next two weeks.

      When F10.7cm goes below ~120 sfu/day, and stays there, it’s all over – until SC25 or #26 max, if there’s high enough flux, that is….

      More details this summer.

      • ! agree with your short term analysis. By the way SFI today is 120.
        My 2650 number ( probably more like 2635 – I just rounded it off a bit) comes from the general trend of the 50 year moving average in Fig 9 in the linked blog. The general trend of the next 1000 years is conservatively forecast to be likely to be similar to the last 1000.Possibly slightly cooler as we go down the precession cycle towards the next ice age.

  23. This is the one that gets me because it’s a suburb of my town-
    http://www.sa.gsa.org.au/Brochures/HallettCoveBrochure.pdf

    In particular from that Point 6-

    Shore platform
    The level shore platform has been eroded by wave
    action across the rocky coastline during the past
    7000 years. The big fold was formed during the
    mountain building about 500 million years ago.
    During the Recent ice age about 20 000 years ago,
    sea level was about 130 metres lower than today
    and South Australia’s coastline was about 150
    kilometres south of where Victor Harbor now is.
    The ice cap started to melt about 15 000 years ago.
    Sea level began to rise and reached its present level
    about 6000–7000 years ago.

    Well 130 metres in a 9000 year period is an average rise of 14.4mm/yr but let’s say those rock gurus got it a bit wrong and it was 130M over 13000 yrs that’s still 10mm/yr average.

    The First Fleet full of carboniferous whitefellas only rolled up in sailing ships in 1788 so where’s the CO2 signal in all that sea level rise warmy folks? Does the truth about Gaia lie in the rocks on the ground or the rocks in your heads?

  24. Of course we need to compare that with the whitefella warming of 0.85mm/yr average-

    “One of the oldest tide gauge benchmarks in the world is at Port Arthur in south-east Tasmania. When combined with historical tide gauge data (found in the London and Australian archives) and recent sea level observations, it shows that relative sea level has risen by 13.5 cm from 1841 to 2000.”

    scroll down to see the Port Arthur tide gauge-
    http://www.cmar.csiro.au/sealevel/sl_hist_few_hundred.html

  25. Why is the burning of fossil fuels considered anthropogenic? Clearly any competent geologist will inform a climate “scientist” that eventually all “fossil” materials will be sucked into the mantel subduction zone and “recycled” i.e. regurgitated in a nearby volcano in a decomposed (burnt, oxidized, etc. ) state. If with the minimal geological training that I received while earning my engineering degree can envision this why can’t the climate “scientists?” Further, it just seem illogical that a gas that is release naturally by every volcano and vent on the surface of the Earth, and Ocean can cause significant changes to the natural balance of nature. The anthropogenic amount produced is an amount that is LESS than 1SD of the amount released naturally. In other words, it is in the NOISE level. it has no significance! It is just not logical it is also not probable or possible and can not be supported by math or any form of science. All charts showing thousand or millions of years of the temperature and CO2 concentrations of Earth show this and support this.
    http://www.geocraft.com/WVFossils/CO2_Temp_O2.html
    The only reason there is a correlation today is that there just happens to be a correlation today.

    • A lot of the carbon sequestered during the Carboniferous and Permian Periods lies on continental cratons not likely to be subducted for a long time, if ever.

      The evolution of seed-bearing land plants in the Devonian Period before the evolution of fungi able rapidly to break them down left later periods a legacy of buried carbon, pulled out of the air.

  26. Thanks, Philip Lloyd. Good article.
    After paying attention to this matter for years, and compiling a lot of diverse climate data.
    I have come to the conclusion that almost all of the global temperature rise in the twentieth century is natural and not caused by the small man-made increase of atmospheric CO2. Also, that CO2 cannot be the controlling factor for global temperature; Sea surface temperatures and ocean circulations powered by the Sun are.

  27. Interesting to note how the ‘global’ average sea level rise nearly doubles the rate measured at Port Arthur which is obviously statistically significant for some-

    “We have used a combination of historical tide-gauge data and satellite-altimeter data to estimate global averaged sea level change from 1880 to 2009. During this period, global-averaged sea level rose about 21 cm, with an average rate of rise of about 1.6 mm/yr over the 20th Century. The sea level record indicates a statistically significant increase in the rate of rise between 1880 to 2009.”

    Either that or you lot are on sinking ground compared to Gondwanaland ;)

  28. Philip Lloyd,

    I think it is great to see attempts to use observational data to estimate natural variability, The mainstream climate community seems to have extremely remiss in that regard.

    I have not managed to access your paper, so perhaps you can answer some questions for me. Which ice cores did you use? How did you estimate the contribution of measurement uncertainty to the total variance?

    • The cores were GISP, GISP 2, Vostock and EPICA Dome C, with data downloaded from National Climatic Data Center. Isotope measurements have a precision of the order of 1 per thousand, which would suggest a temperature precision of the order of 0.3oC at temperatures of ~300K. However, all the samples analysed in this study had well over 200 values, so the precision of measurement should have had little influence on the results.

      • Philip Lloyd,

        Thanks. I have EPICA and Vostok data that I downloaded a few months ago and the files do not have century scale resolution. Perhaps I have the wrong files. Is there a chance that you could provide the raw data file names?

      • Correction! EPICA was EPICA Dome C Ice Core 800KYr Deuterium Data and Temperature Estimates; LAST UPDATE: 11/26/2007 (Replaced age model. This file now includes EDC3
        age model. Previous version of this file dated 10/16/2007 erroneously
        included the older EDC1-EDC2 age model)
        CONTRIBUTOR: Valérie Masson-Delmotte, LSCE/IPSL
        IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2007-091

      • Thanks. I may not have exactly the same files, but they should give me a feel for the data. I am very much interested in the question raised by Frank (May 18, 2015 at 9:26 am) which I think is very important to address.

  29. …was probably caused…strong likelihood…

    Interesting how a likelihood can be “strong”, and so I presume it can also be weak, medium, super strong and super jumbo strong. “Probably” I assume refers to probability but without a defined numerator and denominator to calculate actual probability, it becomes meaningless as a determinate. It is instead conjecture.

    I am not against conjecture in science, it is part of the process. Evolution is a known, Abiogenesis is reasonable conjecture based on available evidence. A competent evolutionary biologist would not claim to know how Abiogenesis works. They know how it might work but if asked how life first began they would have to answer, “We don’t know, we got some ideas”.

    It seems the expression “I don’t know” has been banned from climate science creating shoddy differentiation between what is known and not known. This then becomes fodder, inferior but readily available material for heads of state to engage in all manner of idiocy.

    • ‘settled science’ has no room for ‘we don’t know ‘ for they understand that by admitting that their already not great case becomes weaker still . Its the same reason they ‘need ‘ the unprecedented idea therefore there is time to waste, they are trying to rush things through before any ‘hard questions ‘ get asked .

  30. What fits the global temperature trend data the best since the Holocene Optimum- Present is what I suggest below.

    My thoughts on what drives the climate conform to what the data shows(present/past), unlike AGW theory which totally ignores the data both present and past.

    AGW theory wants the data to conform to what it suggest, not the other way around.

    More data which shows since the Holocene Optimum from around 8000BC , through the present day Modern Warm Period( which ended in 1998) the temperature trend throughout this time in the Holocene, has been in a slow gradual down trend(despite an overall increase in CO2, my first chart ), punctuated with periods of warmth. Each successive warm period being a little less warm then the one proceeding it.

    My reasoning for the data showing this gradual cooling trend during the Holocene ,is Milankovitch Cycles were highly favorable for warming 10000 years ago or 8000 BC, and have since been in a cooling cycle. Superimposed on this gradual cooling cycle has been solar variability which has worked sometimes in concert and sometimes in opposition to the overall gradual cooling trend , Milankovitch Cycles have been promoting.

    Then again this is only data which AGW enthusiast ignore if it does not fit into their scheme of things. I am going to send just one more item of data and rest my case.

  31. Lloyd: It is meaningless to compare the amount of variation in temperature at one location – the site of an ice core in Greenland – with variation in global temperature – the AVERAGE of many different locations. You don’t have to wait a century to observe a 1 degC change in mean annual temperature at one location – it happens EVERY year at any one location. The standard deviation in mean ANNUAL temperature at any one location on the planet is about 1 degC.

    This happens because heat is chaotically distributed around the planet by wind and ocean currents. Unusual warmth is observed in one locations is often (but not always) associated with unusual cold in another. A static Rossby wave brought unusual warmth to Alaska last winter and cold to the East Coast of the US (and the low pressure systems which tend to follow such waves brought little precipitation to California and the western US). ENSO shifts heat between the Eastern and Western Equatorial Pacific. The Arctic Oscillation shifts heat between the Arctic and temperate zones of the NH. The AMO shifts heat between the North Atlantic (near your ice core data) and the ocean further south. So mean annual temperature in Greenland is far more variable than mean global temperature.

    Redistribution of heat within the planet changes the mean annual temperature of any one location, but redistribution can’t change mean annual temperature of the whole planet! In the long run, mean GLOBAL temperature varies only* by changing: 1) the amount of incoming radiation (solar TSI times albedo) and 2) radiation to space (emitted and absorbed by GHGs).

    *There are some possible exceptions to this generalization: 1) Since the deep ocean is far colder than the surface, changes in the slow rate of exchange (upwelling and downwelling) between the surface and the deep ocean can change global climate for a long time without changing the flux of heat into and from the whole planet. However, except for some polar regions, the ocean is stably stratified – with less dense warm water on the surface and colder water below. 2) Since radiation is emitted following a T^4 law, more evenly distributing heat within the planet will decrease OLR and decrease mean global temperature. The slow movement of continents certainly changes the heat flux to the polar regions by ocean currents.

    • The Greenland ice sheets are regional, since the water that ends up there comes from most of the N. Atlantic.

    • I chose not one, but four points, and they all agree on the timing and magnitude of the major events, so perhaps, while you have a point, you may need to reconsider it in this light.

    • One of the many zany aspects of the CACCA ho*x is the idea that the atmosphere warms the oceans measurably through back radiation or convection from the allegedly warmer air. That’s the tail wagging the dog on a planetary scale.

      The oceans give up their stored solar heat through circulations and oscillations such as the AMO and ENSO. The GHE from CO2 is mainly an effect, not a cause.

      • I agree.

        Now with the decline in solar cycle 24 and with solar activity perhaps staying at very low levels for several years the nonsense of AGW theory will finally come to an end.

        I expect sea surface temperatures to eventually fall in response to very low solar activity.

  32. Okay, let me get this straight.

    Temperature is an average — the average kinetic energy of a collection of objects with some distribution of momenta.

    Average global temperature is then an average of averages, right?

    Does not the Yule-Simpson Paradox (or Effect) — a paradox in probability and statistics in which a trend that appears in different groups of data disappears or reverses when these groups are combined — apply here?

    And if the Yule-Simpson Paradox is at play, and the means are meaningless, what information do standard deviations contain?

    (Don’t even get me started on ‘average standard deviations.’)

    • Max Photon,

      I don’t think the Simpson Paradox applies here as long as the data from the different groups are properly weighted, but I have not tried to prove it. Do you have some reason to think it is an issue?

  33. Anyone with the modicum of come sense can see the c02 signal is between 4 and 6th s of a degree of warming for a doubling of c02.This makes it impossible to be concerned about the climate scare meme.

  34. Well the world’s just seen again that Anthony Watt’s and his followers don’t understand anything about statistics. This is beyond stupid. Can’t wait for this little gem to be destroyed on the other blogs.

      • Fine. Do you honestly think that it is valid to compare estimates of variability derived ice cores against estimates of variability derived from satellite records/temperature station measurements? [snip . . irrelevant invective is not useful . . mod]

      • Siberian Husky,

        We have no estimates of natural variability “derived from satellite records/temperature station measurements”. Unless, that is, you assume that man has had absolutely no impact on the climate.

      • No, no, no, you’re completely missing the point. It’s totally inappropriate to compare apples and oranges, as it is completely pointless wasting one’s time trying to educate anyone on this blog. Using ice cores as a proxy for global temperature average involves massive uncertainties in measurement. These will also contaminate any estimate of variability of variation over a century using these samples. Therefore it’s totally inappropriate to compare them to measurements of variability over a time frame using satellite data or temperature records without some sort of adjustment for this.

      • Mr. “No, no, no”

        If you don’t like ice cores, and you don’t like satellite data, then what system do you use?

        Witch doctor juju?

    • Siberian_Husky,

      “Anthony Watt’s and his followers”? Anthony has followers? What do you think he is, some sort of prophet? I am pretty sure he has no such delusions and would not want any “followers”.

      From what I have seen, the commenters here resemble a herd of cats. Blind, drunken cats in some cases. But pretty much all not following anyone’s lead but their own. Unlike what you will find at a site like, say, ATTP.

      Yes, there is a lot of nonsense to be found here. Beats an echo chamber, in my book. It would be better if people would try to make constructive comments, rather than just mouthing off.

    • One constant with the puppy, he can’t be bothered with actually demonstrating the claims he makes.
      Growling about how others are wrong seems to be the limit of his mental capacities.

  35. Philip Llloyd,

    It seems you paper is in some pre-publication state behind a double paywall, so I can not access it. So I am reduced to trying to reproduce it blind. So far, I have managed to take a quick look at the last 8000 years of EPICA and GISP2 data. Just on the raw numbers, standard deviations about the mean in each data set are about 0.8 K, smaller than the 100 year values you report. I can not see why that would be. I took 100 year averages and find standard deviations between successive points of 0.45 K (GISP2) and 0.48 K (EPICA); much smaller than what you report. As Frank points out, global average values will be smaller due to averaging out local effects. Also, global averages will be smaller since high latitudes have higher temperature variability. And some of that is measurement uncertainty. So it is starting to look to me like the last 100 years may well be unprecedented.

    • In all the records there are records which differ by 100 +/- 10 years. I looked at the differences between each of those records – and there were several hundred such pairs for each core. . They were normally distributed and the mean was close to 100 years. I also de-trended the data before taking the differences because there is some Milankovich cooling going on over the past 8000 years – detrending had a minimal effect on the result. It is quite a simple experiment – sorry about the paywall!

  36. Greenland ice cores may not be a good proxy for global temperature changes. RSS data show Arctic temperature trend is 2.5 times greater than global temperature trend

    • You can see to what extent the temperature in the Arctic depends on the circulation and the importance of the strength of the polar vortex in the stratosphere in the winter.

      It is worth to compare it with Earth’s magnetic field.

      • The CRII leads to the production of odd nitrogen. For example, fast secondary
        electrons (e∗) can dissociate the nitrogen molecule, N2+e∗→2N(2D)+e, and almost
        all of the N atoms in the excited 2D state react with O2, producing nitric oxide,
        N(2D)+O2 →NO+O. Vitt and Jackman (1996) estimated CRII to produce 3.0 to
        3.7×1033 molecules of odd nitrogen per year in the global stratosphere, which amounts
        to about 10% of the NOx production following N2O oxidation. They also mention that
        the northern polar/subpolar stratosphere (>50◦ N) is believed to be supplied with NOx
        in equal amounts by GCRs (7.1 to 9.6×1032 molecules/yr) and by N2O oxidation (9.4
        to 10.7×1032 molecules/yr). In the deep polar winter stratosphere, when air masses
        experience sunlit periods only infrequently and photolysis of HNO3 becomes negligible,
        CRII become the only source of NOx, revealing the importance of GCRs in high latitudes.
        http://www.researchgate.net/profile/I_Usoskin/publication/49611898_Influence_of_galactic_cosmic_rays_on_atmospheric_composition_and_temperature/links/0deec518021e5b06ef000000.pdf

      • ABSTRACT The odd nitrogen source strengths associated with solar proton events (SPEs), galactic cosmic rays (GCRs), and the oxidation of nitrous oxide in the Earth’s middle atmosphere from 1974 through 1993 have been compared globally, at middle and lower latitudes (50 ø) with a two-dimensional photochemical transport model. As discovered previously, the oxidation of nitrous oxide dominates the global odd nitrogen source, while GCRs and SPEs are significant at polar latitudes. The horizontal transport of odd nitrogen, produced by the oxidation of nitrous oxide at latitudes

        A comparison of sources of odd nitrogen production from 1974 through 193 in the Earth’s middle atmosphere as calculated using a two-dimensional – ResearchGate. Available from: http://www.researchgate.net/publication/242267498_A_comparison_of_sources_of_odd_nitrogen_production_from_1974_through_193_in_the_Earth%27s_middle_atmosphere_as_calculated_using_a_two-dimensional [accessed May 21, 2015].

  37. In short, the null hypothesis that long-term temperature changes are natural cannot be rejected. Why is this hard?

  38. A few problems with Dr Lloyd’s logic:

    1) No smoking gun: Yes, climate change has happened in the past, for other reasons (e.g.: solar and volcanic activity) but none of these triggers have occurred recently. Dr Lloyd basically saying temperature has changed before (for other reasons) so it could be changing now for the same reasons, without showing those same drivers have occurred.

    2) Coupled system: We know for a fact CO2 increases temp. We know for a fact we are putting CO2 into the atmosphere, and levels have risen significantly. To deny the CO2 we are putting into the atmosphere is having an effect on temperature, you have a burden of proof, i.e.: prove that CO2 can have no effect. Also not shown. Worse, you have to disprove the empirical finding that our CO2 – based on C12/13 isotopes – residing in the lower atmosphere, is causing current warming. You can’t just pretend those proofs don’t exist to suit yourself.

    3) Selective variables: Natural variability could be worsening warming… It could also be slowing down human-induced warming. There’s basically a 50:50 chance. To choose the favoured outcome is plain wrong, especially when the same data may actually prove real warming is twice as bad (rather than not as bad). This worse-case is actually more probably, since a negative Pacific Decadal Oscillation (which we’ve been in for the past several years) normally causes cooling, but this time has been more than offset by other warming factors (i.e.: real warming is potentially much worse than current perceived warming.)

    4) CO2 vs Temp: We also know there is a delayed effect on temp from rising CO2, which accumulates in the atmosphere meaning the full temperature effect of current emissions hasn’t occurred yet. (Just as there is a delayed effect on CO2 from rising temp – it is a feedback loop.) Dismissing temperature variability is therefore inconclusive without also explaining CO2 variability, which cannot be explained by the same logic. Not only are current CO2 levels outside the range of natural variability for 8000 years, they are outside the natural variability for millions of years.

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