A compilation of lower climate sensitivities, plus a new one

Still Another Low Climate Sensitivity Estimate

Guest post By Patrick J. Michaels and Paul C. “Chip” Knappenberger

Global Science Report is a weekly feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”

As promised, we report here on yet another published estimate of the earth’s equilibrium climate sensitivity that is towards the low end of the United Nations’ Intergovernmental Panel on Climate Change (IPCC) range of possibilities.

Recall that the equilibrium climate sensitivity is the amount that the earth’s surface temperature will rise from a doubling of the pre-industrial atmospheric concentration of carbon dioxide. As such, it is probably the most important factor in determining whether or not we need to “do something” to mitigate future climate change. Lower sensitivity means low urgency, and, if low enough, carbon dioxide emissions confer a net benefit.

And despite common claims that the “science is settled” when it comes to global warming, we are still learning more and more about the earth complex climate system—and the more we learn, the less responsive it seems that the earth’s average temperature is to human carbon dioxide emissions.

The latest study to document a low climate sensitivity is authored by independent scientist Nic Lewis and is scheduled for publication in the Journal of Climate. Lewis’ study is a rather mathematically complicated reanalysis of another earlier mathematically complicated analysis that matches the observed global temperature change to the temperature change produced from a simple climate model with a configurable set of parameters whose actual values are largely unknown but can be assigned in the model simulations. By varying the values of these parameters in the models and seeing how well the resulting temperature output matches the observations, you can get some idea as to what the real-world value of these parameters are. And the main parameter of interest is the equilibrium climate sensitivity. Lewis’ study also includes additional model years and additional years of observations, including several years from the current global warming “hiatus” (i.e., the lack of a statistically significant rise in global temperature that extends for about 16 years, starting in early 1997).

We actually did something along a similar vein—in English—and published it back in 2002. We found the same thing that Lewis did: substantially reduced warming. We were handsomely rewarded for our efforts by the climategate mafia, who tried to get 1) the paper withdrawn, 2) the editor fired—not just from the journal, but from Auckland University, and 3) my (Michaels) 1979 PhD “reopened” by University of Wisconsin.

Lewis concludes that the median estimate of the equilibrium climate sensitivity is ~1.7°C, with a 90% range extending from 1.0°C to 3.0°C. (That’s almost exactly what we found 11 years ago.)

Based on this result, we welcome Lewis (2013) to the growing list of results published in the scientific literature since 2010 which find the climate sensitivity to be on the low side of the IPCC. God knows what the climategaters are emailing today.

Figure 1 illustrates all the new results as well as the IPCC’s take.

Take special note of the new findings (and their mean) in relation to the black bar at the top labeled “IPCC AR5 Climate Models.” Of the 19 state-of-the-art climate models used in the IPCC’s newest Assessment Report (which is still in its draft form) exactly zero have an equilibrium climate sensitivity that is as low as the mean value of estimates from the recent literature included in our Figure.

Based on the collection of results illustrated in our Figure, the future climate change projections about to be issued by the IPCC are off by an average of a whopping 70 percent.

No wonder the IPCC is reluctant to lower their best estimate of the actual value of the earth’s equilibrium climate sensitivity. If they did, they would be admitting that the collection of climate models they have chosen (there is choice involved here) to project the earth’s future climate are, well, how should we put this, wrong!…which would mean that so too is the rate at which the sky is falling, according to the USGCRP and the US EPA.

We, at Cato’s Center for the Study of Science, will continue our efforts to portray the evolving state of climate science and to convince the powers-that-be that national and international assessments upon which EPA regulations are founded (and loony proposals for a carbon tax are based) are fatally flawed. Or as we put it, in our recent (April 12) review of the USGCRP’s draft “National Assessment,” in its current form, “the NCA [National Climate Assessment] will be obsolete on the day of its official release.”

References:

Aldrin, M., et al., 2012. Bayesian estimation of climate sensitivity based on a simple climate model fitted to observations of hemispheric temperature and global ocean heat content. Environmetrics, doi: 10.1002/env.2140.

Annan, J.D., and J.C Hargreaves, 2011. On the genera­tion and interpretation of probabilistic estimates of climate sensitivity. Climatic Change, 104, 324-436.

Hargreaves, J.C., et al., 2012. Can the Last Glacial Maximum constrain climate sensitivity? Geophysical Research Letters, 39, L24702, doi: 10.1029/2012GL053872

Intergovernmental Panel on Climate Change, 2007. Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Solomon, S., et al. (eds). Cambridge University Press, Cambridge, 996pp.

Lewis, N. 2013. An objective Bayesian, improved approach for applying optimal fingerprint techniques to estimate climate sensitivity. Journal of Climate, doi: 10.1175/JCLI-D-12-00473.1.

Lindzen, R.S., and Y-S. Choi, 2011. On the observational determination of climate sensitivity and its implica­tions. Asia-Pacific Journal of Atmospheric Science,47, 377-390.

Michaels, P.J., et al., 2002. Revised 21st century temperature projections. Climate Research, 23, 1-9.

Ring, M.J., et al., 2012. Causes of the global warming observed since the 19th century. Atmospheric and Climate Sciences, 2, 401-415, doi: 10.4236/acs.2012.24035.

Schmittner,  A., et al. 2011. Climate sensitivity estimat­ed from temperature reconstructions of the Last Glacial Maximum. Science, 334, 1385-1388, doi: 10.1126/science.1203513.

van Hateren, J.H., 2012. A fractal climate response function can simulate global average temperature trends of the modern era and the past millennium. Climate Dynamics,  doi: 10.1007/s00382-012-1375-3.

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60 thoughts on “A compilation of lower climate sensitivities, plus a new one

  1. To summarize, of the studies since 2010, six find CS under 2 degrees C., six over & two exactly that amount. Not one finds CS as high as AR4 or AR5. Will IPCC ignore these papers? What about CACCA (catastrophic anthropogenic climate change alarmists) in general?

  2. Low sensitivity is what the Earth’s climate system has shown to have now.
    This may be because it contains a controlling thermostat; the water cycle.
    Mainly negative feedback from clouds is what appears to act.
    In my climate pages I link to many interesting reference papers on this.

  3. Could someone tell me why an increase of 2°C would cause such devastation as is forecast (without, oddly, any specifications as to what devastation) to this planet?

    Also, from what point is this 2°C measured from – now, or at some point in the past which was, or nearly was, 2°C cooler than now, or even some point in the future that is warmer (by an unknown amount) than now?

    Finally, could it be possible that this 2°C actually be of benefit to our life on this planet?

  4. All the studies cited are not of equivalent quality. By which is meant not academic content, but rather underlying methodological uncertainty. The higher quality studies all seem to come in below 2, but above 1.5. Close enough for ‘government work’.

  5. Great to see the wealth on recent posts on sensitivities , which is the crux of the argument as the authors point out.

    From a previous comment , note that in looking at observed temp & CO2 data over the industrial era, that we have an observed temp change of ~ 1.5 C/doubling, regardless of if CO2 is the cause of this change or not (a correlation based on the pertinent math). See :

    http://wattsupwiththat.com/2013/04/24/some-sense-about-sensitivity/#comment-1286094

    Note on figure 1 of this post that nearly every estimate of sensitivity is greater than 1.5. There is a profound implication here which I want to expand upon.

    For any estimate greater than 1.5, it is absolutely implied there are other forcings at work which are trying to push global temps down – it’s the only way you can have the observed change in industrial era temps AND be consistent with these estimates of sensitivity. If the CAGWers truly believe these higher sensitivity estimates, one has to conclude that our anthropogenic CO2 output is having a demonstrable net positive effect – without it, we would be seeing considerable global cooling (with the net cooling be greatest for the greatest sensitivity estimates). In all periods of history , colder has been bad for humanity.

    Of course, the alternative to this is that other forcings are net neutral or potentially positive. If this is the case, then CO2 sensitivity has to be even less than 1.5 (so that we can get the net observed 1.5 C / doubling ). In this case, the CAGWers are not just wrong, but wildly wrong. With such a low sensitivity, the implication of this case is that CO2 will have little meaningful impact on temps.

    So, given the observation based on data that we have seen a net 1.5C / doubling trend over the last 120 + years, we can conclude one of 2 things :
    1) If we have a sensitivity higher than 1.5 ( as CAGWers suggest), we are doing ourselves a huge favor by continuing to emit CO2 & keeping global temps from plunging
    2) If we have a sensitivity lower than 1.5 , increased CO2 will produce irrelevant temperature changes.

    I hope everyone can appreciate the implication – in either case, non matter how you look at, there is absolutely no argument that we should reduce CO2 – AND this is based on data only – no models required.

  6. “By varying the values of these parameters… you can get some idea as to what the real-world value of these parameters are.”

    No, you actually cannot do so to any useful degree of precision.

    The models are way too complex and have way too many tunable parameters to be able to declare any subset of them to be valid in the real world based on how well the model output matches the observations.

  7. Drs. Michaels and Knappenberger:

    By definition, the equilibrium climate sensitivity (TECS) is the change in the equilibrium temperature at Earth’s surface from a change in the logarithm of the atmospheric CO2 concentration. As the equilibrium temperature is not an observable, when claims are made about the magnitude of TECS, these claims are insusceptible to being tested. Thus, TECS is a scientifically untenable concept.

  8. The sensitivity of 1.1℃ is like the Shwartzchild Radius of climate. You can get closer and closer to it but you can’t pass through or your grants will vanish.

  9. Dr Gray, you Sir are a true New Zealander. Thank you for your contribution in unravelling this climate nonsense.

  10. I am struggling to understand why the AR5 can give the modelled estimate and ignore the scientific papers. Isn’t there supposed mandate to review the scientific literature, not promote somebody’s model? Is there no shame, accountability or scrutiny? Will the MSM even notice?

  11. Two posts in a row by the old guard. Let’s raise a toast to the old guard!

    Pat Michaels does not mention that he was fighting on the same issue well before 2002. In the early 1990s Michaels (and others) had been pointing out that the high CO2 sensitivity factored into the climate models was not matching the recent temperature trends. Then in 1992-3 the modellers started introducing a damper to simulate the impact of sulphate emissions. This meant that only a minimal reduction in the CO2 sensitivity range was required to give a much better match with the temp record — including the difficult pause in warming during the 1970s.

    When in April 1995 such CO2+Sulphate model-run results by Mitchell (at the Met) appeared in Chapter 3 of the review draft of SAR, Michaels was suspicious that these simulations were really doing what they claimed. He wanted to look at polar and southern hemisphere results — where the sulphate impact should be almost zero — and see how they these zones tracked in the new CO2+Sulphate runs. He was suspicious because he had seen model results where the dampening was much more widely distributed (and therefore impacting greater on the overall result) than the limited impact Sulphate should over the industrial mid-lat NH.

    As an expert reviewer for the IPCC he requested this model results from the IPCC and then directly from Mitchell. Mitchell refused to provide Michaels with the zonal breakdown. After a number of refusals, Mike MacCracken got involved on behalf of the US delegation. Mitchell refused MacCracken’s requests. One reason given for refusal was that the results had not yet been published. After the results were peer-review published Mitchell still refused. Eventual this dispute hit the science press and was criticized not only in a US House of Reps hearing but also in a Nature editorial. Mitchell never provided the model data zonal breakdown and perhaps no one will ever know whether Michaels’ suspicions were correct.

    Meanwhile, Mitchell’s graph went on to be championed as one of the key findings in SAR. In a silent acknowledgement of the previous skeptical critique, it appear below a chart of a CO2-only model run projecting way above the temp record after the 1940s. This pair of charts appeared not only in Chapter 3, but they were also inserted in the final draft of Chapter 8 and place up front in the Policymaker’s Summary.

  12. Jeff L says:
    April 25, 2013 at 3:18 pm

    “…we have an observed temp change of ~ 1.5 C/doubling, regardless of if [sic] CO2 is the cause of this change or not…”

    “Regardless…if CO2 is the cause”. If CO2 isn’t the cause, what the heck are you doubling?

    JP

  13. GlynnMhor, above, is right: Lewis (2013) merely “reconstructs” the temperature record, as it were, using a highly-tunable model (that is assumed to be based upon “settled science”, behind all of its tunable parameters, but is not). Just another example of modelling portrayed as real-world experiment (the naive use of “objective Bayesian probability” notwithstanding). This is surely precisely why peer-review is not to be trusted–because the “peer” reviewers have not learned, and have no intention of learning, that even the most fundamental “science” in the models is NOT settled (specifically, the mixing together of directed radiation and diffusive heat radiation–which has not been disentangled from heat convection and conduction, as its use implies–in the radiative transfer theory; the idea of “radiative forcing”, by any and all variables, as the governing physics; and the greenhouse effect–of increasing temperature with increasing CO2–concocted from that incorrect physics).

    As for this “compilation”, Michaels and Knappenberger need to know about the definitive experimental calculation of the true CO2 climate sensitivity (which is zero), from the amazing results of the (first and only) proper Venus/Earth temperatures comparison, in

    CO2 Climate Sensitivity Vs. Reality.

  14. Niff says:
    April 25, 2013 at 5:05 pm

    “I am struggling to understand why the AR5 can give the modelled estimate and ignore the scientific papers.”

    Struggle no more. AR5 isn’t out yet. About a year to go. JP

  15. So how does a rotating body like a planet, in the presence of a radiant energy source, such as the sun, ever rach thermal equilibrium ?

    Just thought I would ask.

  16. Niff says:
    April 25, 2013 at 5:05 pm
    I am struggling to understand why the AR5 can give the modelled estimate and ignore the scientific papers.
    =========
    because the very last thing the IPCC will publish is a report that says “everything is fine, nothing to worry about, we can all go home”. without a crisis the IPCC would have no reason to exists. no more lavish conferences with jet setters and limousines, no more grants to save the world. a lot of unemployable academics and bureaucrats would have to go out and try and find jobs.

    In every climate conference the first order of business is to decide the location for the next conference. the second order of business is to party like the world is about to end. having drunk your fill and shagged your brains out, the last order of business is to get your picture in the paper. either posing with some high up mucky mucky, or in flagrante on the dance floor with his wife. then off to the airport, publish a paper on your vast accomplishments and sit back and enjoy life. you’ve earned it.

  17. George, you know it can’t in any instantaneous sense be at equilibrium, but it can be at a quasi-equilibrium state in which it oscillates about an equilibrium mean (whatever that means!).

  18. george e. smith says:
    April 25, 2013 at 6:28 pm

    So how does a rotating body like a planet, in the presence of a radiant energy source, such as the sun, ever rach thermal equilibrium ?

    Just thought I would ask.

    About ten feet below the surface of the moon, the temperature is pretty much constant. With no pesky atmosphere and ocean, the moon behaves exactly as the fairly simple physics equations predict.

    • commieBob:

      You claim that: “About ten feet below the surface of the moon, the temperature is pretty much constant.” Can you provide empirical substantiation of this conclusion? If not, your argument that “With no pesky atmosphere and ocean, the moon behaves exactly as the fairly simple physics equations predict” is circular.

  19. I feel obliged to mention in all of these threads about climate sensitivity (“CS”), is that CS is itself likely a function of global temperature.

    CS is not a single number, like the gravitational constant, that applies at all times and temperature ranges. CS is a function of the net impact of a large number of feedbacks, some positive, some negative, some fast and some slow. None of these feedbacks are themselves constant over a wide range of earth’s temperatures.

    It is more likely that at the depths of an ice-age, CS is low, it rises with temperature and peaks in the mid-range between ice-age and interglacial. CS then falls again as temperatures approach today’s relatively high levels when glaciation is near its minimum. This is the only pattern of CS that can explain the planet’s history of tipping back and forth between two stable thermal equilibria, while spending virtually no time in between.

    So, if a study to estimate CS focuses on either ice-age conditions or modern conditions, it will likely arrive at a low value for CS. However, studies of the intermediary periods of glacial advance or retreat, will arrive at high values of CS.

    What ultimately matters is today’s value, which appears to be low, and suggests that temperatures can’t get much higher than they are now. Which is in agreement with several million years of history where no tipping points or runaway warming was observed.

    • Russ R.:

      The post of Michaels and Knappenberger is not about your “climate sensitivity” (CS) but rather is about “the equilibrium climate sensitivity” (TECS). Though CS is a variable, TECS is a constant.

  20. Earth’s climate and “mean temperature” is dependant on many variables, including position of the continents, deep ocean currents, tilt wobble, tilt precession and orbital parameter variations! (all long term influences) It DOES NOT depend on CO2 concentration levels! From ice core analysis, CO2 concentrations lag Earth’s temperature changes: rising 200-800 years AFTER the Earth warms and falling 600-2,000 years AFTER the Earth cools! CO2 concentrations are a lagging indicator, NOT a forcing! Take CO2 concentrations out of the models and the real dominant forcing becomes obvious: Solar variability. We have wasted billions, it not a couple trillion dollars chasing our tail. Process control engineers have been laughing at AGW for three decades!

    Take CO2 concentrations out of the models and see what happens. Then you can truly derail the AGW religion and gravy train!

    Bill Yarber

  21. John Parsons says:
    April 25, 2013 at 5:33 pm

    “Regardless…if CO2 is the cause”. If CO2 isn’t the cause, what the heck are you doubling?”

    ——————————

    Maybe I didn’t state this in a way that was fully understandable. Basically, if you ASSUME that all temp change over the industrial era is due to CO2 & all other forcing is net zero, then correlating temps & CO2 over that time range yields ~ 1.5 °C/doubling sensitivity . Now as far as the assumption, I am not saying that I think that is correct or not – I am not presenting any data which either supports or refutes that assumption. Thus my statement “Regardless…if CO2 is the cause” – because I am not saying CO2 is or is not the cause of the temp change only that what the implied sensitivity is if you make the above assumption. I hope that clarifies for you.

  22. Interesting comedown. But not far down enough for me. I suggest that sensitivity is zero – no warming at all from doubling. That is because Ferenc Miskolczi determined that the absorption of infrared radiation by the atmosphere has been constant for 61 years. At the same time, carbon dioxide went up by 21.6 percent. This substantial increase of carbon dioxide had no influence at all on absorption of IR by the atmosphere. And no absorption means no greenhouse effect, case closed. Put as much CO2 as you want into the atmosphere, you get no warming. That is exactly what we have now. There is more CO2 than ever in the atmosphere and more is added daily but there is no warming and there has been none for 17 years as even Pachauri the railroad engineer has to admit.

  23. “””””…..commieBob says:

    April 25, 2013 at 7:08 pm

    george e. smith says:
    April 25, 2013 at 6:28 pm

    So how does a rotating body like a planet, in the presence of a radiant energy source, such as the sun, ever rach thermal equilibrium ?

    Just thought I would ask.

    About ten feet below the surface of the moon, the temperature is pretty much constant. With no pesky atmosphere and ocean, the moon behaves exactly as the fairly simple physics equations predict…….””””””

    Well I didn’t know we had ever drilled down ten feet into the moon. Didn’t know we had ever drilled down ten inches, or even ten centimetres.
    So what if we put a thermometric sensor say, “about” ten mm below the surface on some ordinary equatorial region of the moon, and monitored that Temperature for say, “about” a month ?

    Would that Temperature reading be “pretty much constant” as would be required for thermal equilibrium, or would it cycle much like the near surface of the earth does “about” every 24 hours.

    If the earth was ever at equilibrium, there would be no weather and no climate. On any given ordinary northern midsummer day, the Temperature at the earth surface is likely to be anywhere (and everywhere) within a 120 deg C range, and it could be as much as a 150 deg C range. And any Temperature within that range could be found at a near infinite number of places on the earth (simultaneously).
    And we are asked to believe that there is no heat (noun) flowing anywhere on that surface.

    People should stop bandying about terms that have precise scientific meaning. Earth does not have any equilibrium Temperature, and never will have one.

  24. Clouds are obviously negative feedback. My guess is <1C for a doubling of CO2. Since 1850, I'd say we've seen .3-.5 of the warming attributed to CO2.

  25. Arno Arrak,

    Thanks for that comment. Dr Ferenc Miskolczi indeed showed that there was no change in atmospheric absorption due to the rise in CO2 over the past six decades. Therefore, CO2 has had little if any effect on global warming. Which explains the absence of global warming during a time when CO2 has risen substantially.

    • dbstealey:

      In proper philsophical terminology, Dr. Miskolsi “inferred” (rather than “showed”) that there was no change in atmospheric absorption due to the the rise in CO2 over the past six decades. One cannot conclude with you that the “CO2 has had little if any effect on global warming” as Miskolsi’s inference could be wrong.

  26. Berniel,

    Thanks so much for recounting the sad situation with John Mitchell and the IPCC. You remind me that I need to go down to Charlottesville, where my paper letters are in a U-Store-It. I also need to find a letter from Steve Schneider where he refuses to publish a paper of mine because he “had to hold it to a higher standard of review” because it was “counter-paradigm”, though his journal defined the paradigm.

    Many thanks. Nice to see people have noticed the horrors of this war. Unfortunately, it is not over.

    PJM

  27. george e. smith says:
    So how does a rotating body like a planet, in the presence of a radiant energy source, such as the sun, ever rach thermal equilibrium ?

    Flat global means, not flat at a point location. Long term charts show we’re always changing though.

  28. The Arrhenius theory is simply wrong. Doublings of CO2 have zero effect on global temperature. You are giving “Voodoo Science” credibility by discussing the climate sensitivity to doublings of CO2 concentration.

  29. Doublings of CO2 have zero effect on global temperature.

    So you’re not just saying there’s no scary rise in temperature, or any rise, you’re saying it has absolutely no impact on temperature at all.

    Do you think dumping an atmosphere of CO2 on the moon would not change it’s surface temperature? Would it not serve to compress the day/night extremes?

  30. DaveA says:

    April 25, 2013 at 9:51 pm
    Do you think dumping an atmosphere of CO2 on the moon would not change it’s surface temperature? Would it not serve to compress the day/night extremes?
    <<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>
    it is water that produces the greenhouse effect, not CO2. It is a myth that CO2 contributes to the GHE here on earth. The absorption spectrum of CO2 is too narrow and can not significantly retard IR. Hansen’s greenhouse Venus is egregious error.

  31. It is atmospheric mass (including liquids such as oceans as well as gases) that produce the greenhouse effect.

    Composition changes only induce circulation changes.

  32. george e. smith says:

    “Well I didn’t know we had ever drilled down ten feet into the moon. Didn’t know we had ever drilled down ten inches, or even ten centimetres.
    So what if we put a thermometric sensor say, “about” ten mm below the surface on some ordinary equatorial region of the moon, and monitored that Temperature for say, “about” a month ?”

    “We” did exactly that on the Apollo 15 and 17 missions which inseted thermal probes in drilled holes to a depth of about 5 and 8 feet repectively (the Apollo 16 probe failed due to a broken cable). The holes were actually about 10 feet deep, but the probes could not be inserted fully.
    At a depth below about 3 feet there was no diurnal (monthly?) temperature variation. Temperatures at this depth in the four probes varied from 250 to 255 K.

    These results can be generalised to other areas by studying the thermal neutron flux as measured by the Lunar Prospectors.

  33. mpainter says:
    The absorption spectrum of CO2 is too narrow and can not significantly retard IR.

    That statement puts you in a different category to someone like Stephen Wilde above, who doesn’t acknowledge IR as a factor. It sounds like you think there is a sensitivity to CO2.

    Given how much energy is already in the climate system a 1 C increase from 15 C isn’t really adding much extra energy. It’s a 0.35 % increase in Kelvin, which starts at the null energy state (nothing about “big numbers”, energy). Is 0.35 % significant? To humans maybe, but our goosebumps aren’t a good indication of relative energy change.

  34. Terry Oldberg says:

    April 25, 2013 at 7:29 pm
    Russ R.:

    The post of Michaels and Knappenberger is not about your “climate sensitivity” (CS) but rather is about “the equilibrium climate sensitivity” (TECS). Though CS is a variable, TECS is a constant

    An instantaneous constant ?? or quasi-constant ? Or constant of the moment ? The climate, I believe, has never reached equilibrium and never will and therefore TECS is an imaginary quasi-constant of no real value except in climate models.

  35. DaveA says:

    April 25, 2013 at 9:51 pm
    Do you think dumping an atmosphere of CO2 on the moon would not change it’s surface temperature? Would it not serve to compress the day/night extremes?

    Mars’ atmosphere is 95% CO² and still bloody cold. Atmospheric pressure, on the other hand, is very low due to low gravity. It lost most of it’s atmosphere a long time ago due to it’s low gravity and inability therefore to hold onto the gases.

  36. Friends:

    I agree that radiative forcing changes affect climate. But I write to again remind that an explanation of observed climate changes in the holocene does not require existence of any driver of climate change.

    Hence, assumptions that estimated climate sensitivity is indicated or constrained by recent temperature changes (over the last decade or the last century) are mistaken in principle.

    An oscillating chaotic system can be expected to vary without any driver.

    Chaotic systems vary, and purely harmonic variations may occur independently of any chaotic effects.

    Please remember that global temperature rises 3.8 deg.C during 6 months of each year and falls by 3.8 deg.C during the other 6 months of each year. But global temperature only rose about 0.8 deg.C throughout the last century.

    In other words, the rise in global temperature over the last century was about a fifth of the rise in global temperature which happens during 6 months of each year.

    The trivial 0.8 deg.C rise throughout the last century could be an effect of harmonic oscillation.

    An oscillating system can be expected to exhibit harmonics over periods much longer than a single oscillation. The observed changes in global temperature with apparent frequencies of ~900 years and ~60 years could be harmonics.

    So, both chaos and harmonics could each be expected to provide variations to global climate of the form and magnitude recently observed. Therefore, such variations do not require any driver and the observed variations may not have had any driver.

    The assumption that an estimate of climate sensitivity is indicated or constrained by recent temperature changes (over the last decade or the last century) is without foundation and is improbable.

    Richard

  37. Is it possible that all these studies have a built-in assumption: that the warming was caused primarily by CO2? Of course, if the lack of warming continues then the sensitivity values will continue to get smaller for the obvious reason.

    But what if the basic assumption is wrong and that the 20th century warming had some other cause? Almost half of the warming occurred before there was enough CO2 to have an effect, even based on the AGW theory. And there have been numerous historical warming periods that could not have been caused by CO2.

    It seems to me that the best evidence comes from the ice cores, which document an unending laboratory experiment conducted by Nature for almost the last million years. We now know that the CO2 levels follow the temperature, for the obvious eason, and so the temperature could not have been driven by CO2 changes. As far as I’m aware, the ice core records provide not a shred of evidence that changes in CO2 can cause a corresponding change in the temperature. In other words, the ice core records strongly suggest that the CO2 sensitivity is very close to zero.

    It’s certainly good news that science is slowly correcting itself as more studies report lower sensitivity values. But I suspect studies that report a zero sensitivity are much closer to the truth.
    As for the real cause of the warming, both in the 20th century, and in the distant past, here’s a clue: look up at the sky.
    Chris

  38. Well, the continued flogging of climate sensitivity is probably the best avenue for attacking the MMCC monster. Still, it doesn’t make any of these guesses any more valid. One of the problems is they are all based on incomplete knowledge instead of first principles. Until we can understand the first principles they are all suspect.

    One of the first principles that keeps being ignored is the accelerated cooling effect of CO2. While CO2 does slow down the release of surface energy from the planet (the greenhouse effect), it also speeds up the release of atmospheric energy from the planet. This physics is just as valid as the GHE but is never acknowledged by climate scientists. It’s really quite simple.

    When energy gets transferred to a CO2 molecule from O2 or N2 via a collision that energy is likely to be radiated in a random direction. The distance that energy travels before reabsorption is shorter when the energy is radiated downward due to the higher density. Hence, the average distance of any radiation event is towards space. Therefore, it can be said that CO2 statistically acts to accelerate energy flow from the atmosphere to space. The more CO2 … the faster the energy moves upward which increases the probability of a final radiation event to space.

    Where is it coded into climate models? Where is it factored into sensitivity studies? Why is this process ignored?

  39. Harry Huffman, please, your simple comparison between Earth and Venus temperatures at the same pressure altitude in the atmosphere ignores a much greater effect than just Venus being closer to the Sun: The albedo of Venus is so much higher than the Earth that it actually receives LESS solar input to its climate system than the Earth does (as I recall, about 170 W/m2 versus 240 W/m2). How do you factor that in? Are you saying that a planet’s atmospheric temperature does not depend upon how much sunlight is absorbed?..because you have totally ignored this variable (among others).

  40. The higher end bands, how much of that is due to inclusion of models which should have been considered invalid? I mean, surely most of the models that predict low emissions and high temps can’t be justified.

  41. dbstealey says:April 25, 2013 at 7:46 pm

    Arno Arrak,

    Thanks for that comment. Dr Ferenc Miskolczi indeed showed that there was no change in atmospheric absorption due to the rise in CO2 over the past six decades. Therefore, CO2 has had little if any effect on global warming. Which explains the absence of global warming during a time when CO2 has risen substantially.

    I agree, and to perhaps expand on Arno’s point of ‘no greenhouse effect’, I would say perhaps the GHE is maxed out at CO2=~300-400PPM, and further contributions of CO2 are negligible.

  42. @Radical Rodent says:
    April 25, 2013 at 3:16 pm

    Could someone tell me why an increase of 2°C would cause such devastation as is forecast (without, oddly, any specifications as to what devastation) to this planet?…
    Finally, could it be possible that this 2°C actually be of benefit to our life on this planet?
    ————————
    The fact that warming not only is not (on balance) more harmful than helpful, but far more helpful than harmful entirely undercuts the AGW pseudoscience making it irrelevant nonsense. Students of the effects of climate change during the Holocene have known since the 1950s that generally warmer global climate has often coincided with great advances in civilization including the Roman Warm Period and the Medieval Warm Period.
    Please see Thomas Gale Moore’s books:
    Global warming : a boon to humans and other animals
    & Climate of fear : why we shouldn’t worry about global warming

  43. Skeptics sometimes estimate that the human contribution to the increase of CO2 is only 1/40th the total. Then at most 1/40th of the twentieth century warming of 0.6 degrees would have been due to humans.

  44. Ring et al 2012, full copy online at

    http://www.scirp.org/journal/PaperDownload.aspx?paperID=24283

    CS estimates from their Table 4, let’s see if it copies:
    OK, not well. Here’s the beef:

    Table 4. Estimates of climate sensitivity, ΔT2x, total aerosol forcing for year 2000, FA, and oceanic thermal diffusivity κ based on each instrumental dataset.
    Instrumental Dataset

    GISTEMP
    1.45 , CS est. from Instrumental Dataset
    HADCRUT4
    1.61
    NOAA
    1.99
    JMA
    2.01

    Observation *always* trumps theory!

    Cheers — Pete Tillman
    Professional geologist, amateur climatologist

  45. I have a serious problem with the entire concept of “climate sensitivity”. I think it could actually be more ”cargo cult” than atmospheric physics.

    Here is my problem:
    Atmospheric CO2 LAGS temperature T at ALL time scales, from the 9 month delay for ~ENSO cycles to the 600 year delay inferred in the ice core data for much longer cycles.

    When I studied this subject in 2007-2008, the only signal I was able to derive from the modern data was that [dCO2/dt varies ~contemporaneously with T and CO2 lags T by 9 months].

    This physical reality has since been widely accepted, but dismissed as a “feedback effect”.

    This is like saying you cannot hear the orchestra, but you can clearly hear the piccolo.

    I say you ARE hearing the orchestra – atmospheric CO2 lags temperature because temperature drives CO2.

    The observed rise in CO2 may indeed have a significant humanmade component – but is probably driven much more by deforestation than fossil fuel combustion.

    Regards, Allan

    http://wattsupwiththat.com/2013/03/30/the-pitfalls-of-data-smoothing/#comment-1265693

    When I first pointed out this relationship in January 2008 (dCO2/dt varies with T and CO2 lags T by 9 months), it was deemed incorrect.

    Then it was accepted as valid by some on the warmist side of this debate, but dismissed as a “feedback”.

    This “feedback argument” appears to be a “cargo cult” rationalization, derived as follows:
    “We KNOW that CO2 drives Temperature, therefore it MUST BE a feedback.”

    More below from 2009:

    __________________

    http://wattsupwiththat.com/2009/01/21/antarctica-warming-an-evolution-of-viewpoint/#comment-77000

    Time is limited so I can only provide some more general answers to your questions:

    My paper was posted Jan.31/08 with a spreadsheet at

    http://icecap.us/index.php/go/joes-blog/carbon_dioxide_in_not_the_primary_cause_of_global_warming_the_future_can_no/

    The paper is located at

    http://icecap.us/images/uploads/CO2vsTMacRae.pdf

    The relevant spreadsheet is

    http://icecap.us/images/uploads/CO2vsTMacRaeFig5b.xls

    There are many correlations calculated in the spreadsheet.

    In my Figure 1 and 2, global dCO2/dt closely coincides with global Lower Tropospheric Temperature LT and Surface Temperature ST. I believe that the temperature and CO2 datasets are collected completely independently, and yet there is this clear correlation.

    After publishing this paper, I also demonstrated the same correlation with different datasets – using Mauna Loa CO2 and Hadcrut3 ST going back to 1958. More recently I examined the close correlation of LT measurements taken by satellite and those taken by radiosonde.

    Further, I found (actually I was given by Richard Courtney) earlier papers by Kuo (1990) and Keeling (1995) that discussed the delay of CO2 after temperature, although neither appeared to notice the even closer correlation of dCO2/dt with temperature. This correlation is noted in my Figures 3 and 4.

    See also Roy Spencer’s (U of Alabama, Huntsville) take on this subject at

    http://wattsupwiththat.wordpress.com/2008/01/25/double-whammy-friday-roy-spencer-on-how-oceans-are-driving-co2/

    and

    http://wattsupwiththat.wordpress.com/2008/01/28/spencer-pt2-more-co2-peculiarities-the-c13c12-isotope-ratio/

    This subject has generated much discussion among serious scientists, and this discussion continues. Almost no one doubts the dCO2/dt versus LT (and ST) correlation. Some go so far as to say that humankind is not even the primary cause of the current increase in atmospheric CO2 – that it is natural. Others rely on a “material balance argument” (mass balance argument) to refute this claim – I think these would be in the majority. I am an agnostic on this question, to date.

    The warmist side also has also noted this ~9 month delay, but try to explain it as a “feedback effect” – this argument seems more consistent with AGW religious dogma than with science (“ASSUMING AGW is true, then it MUST be feedback”). :-)

    It is interesting to note, however, that the natural seasonal variation in atmospheric CO2 ranges up to ~16ppm in the far North, whereas the annual increase in atmospheric CO2 is only ~2ppm. This reality tends to weaken the “material balance argument”. This seasonal ‘sawtooth” of CO2 is primarily driven by the Northern Hemisphere landmass, which is much greater in area than that of the Southern Hemisphere. CO2 falls during the NH summer due primarily to land-based photosynthesis, and rises in the late fall, winter and early spring as biomass degrades.

    There is also likely to be significant CO2 solution and exsolution from the oceans.

    See the excellent animation at http://svs.gsfc.nasa.gov/vis/a000000/a003500/a003562/carbonDioxideSequence2002_2008_at15fps.mp4

    It is also interesting to note that the detailed signals we derive from the data show that CO2 lags temperature at all time scales, from the 9 month delay for ~ENSO cycles to the 600 year delay inferred in the ice core data for much longer cycles.

    Regards, Allan

  46. Allan MacRae,

    Thanks for your excellent comment above. This chart shows convincingly that ∆T is the cause of ∆CO2.

    But I can find no comparable chart showing that changes in CO2 cause subsequent temperature changes. I like to see scientific evidence to support assertions, such as the assertion that CO2 causes global warming. But any such evidence appears to be completely lacking.

    I think that the warmist side began by assuming an incorrect premise: they believed that CO2, in an atmosphere ruled primarily by convection, acts the same as it does in the laboratory, in a closed container.

    But the real world acts differently, so starting off with the wrong premise has led the warmist crowd to a very wrong conclusion. Based on empirical evidence, ∆T causes ∆CO2 — not vice versa. “Carbon” does not cause any measurable global warming.

    If I am wrong, I will accept that with no problem. But I need solid empirical measurements showing that I’m mistaken. So far, I have been unable to find any such measurements. But not for lack of trying to find them.

  47. “””””…..tty says:

    April 25, 2013 at 11:44 pm

    george e. smith says:

    “Well I didn’t know we had ever drilled down ten feet into the moon. Didn’t know we had ever drilled down ten inches, or even ten centimetres…….””””””” So a whole two holes, one of which was a “dry” hole.

    So if we drill down ten feet on earth and stick a sensor on a shortened cable eight feet down that hole (well drill two, to be sure one will work) How much does simple physics predict; excuse me project, the Temperature will change over 24 hours; wll make it a month, since the moon going around might affect it.

    Was there a point to doing this ? We have enough caves on earth to know, the Temperature doesn’t change down there over time. That’s why they don’t have weather or climate down in caves.

  48. “The Arrhenius theory is simply wrong. Doublings of CO2 have zero effect on global temperature. You are giving “Voodoo Science” credibility by discussing the climate sensitivity to doublings of CO2 concentration.” [Galloping Camel, 4/25/13 at 0933]

    True, Mr. Camel, true. And, often, dignifying nonsense with a response serves only to promote the nonsense.

    HOWEVER, noble warriors for truth such as authors Michaels and Knappenberger are dealing with a cult mentality (and, even more, in the cult’s leaders, with a deep-seated greed for money and or prestige or raw power). Cult members will cling ferociously to their fantasies (and con-artists, to their schtick). Deprogramming (or exposing a con) must be done in painstaking, orderly, steps. Leading off with a bold, grand proclamation of what is REAL is like having a sheepdog charge straight up to the sheep with a loud, “WOOF!” Result: terrified sheep who are listening to no one and running away pell mell.

    Instead of saying to the members of the I Do Believe in Fairies Cult (most of the news media and many politicians fall into this category), “Now, look here, people. FAIRIES – DO – NOT – EXIST and that’s how we know they did not build that castle,” Michaels and Knappenberger are quietly but firmly saying to them, “We are not saying that fairies do not exist, but, we know that fairies did not make that castle because their hands are too tiny [please assume for this hypothetical that the cult defines fairies to be tiny beings who can only make buildings by building them, not using their magical powers which are for other things like sleeping potions and such like]. And, as to the cons, they are proceeding like a trial attorney, step… by careful……. step, demolishing the other side’s case by showing each piece of its evidence, one by one, to be false or irrelevant.

    Knappenberger and Michaels have “pledged [their careers] and [their] sacred honor” in joining in the fight for truth. I feel about them as I feel about the signers of the American Declaration of Independence. Such men deserve our respect and wholehearted support. Your criticism touched a nerve and I leapt to their defense. Please forgive me if I have attacked your essentially true statement overzealously. We are both on the same side!

    THANK YOU, Mr. Michaels and Mr. Knappenberger!

  49. Roy Spencer says:
    April 26, 2013 at 7:22 am
    //////////////////////////////
    Dr Spencer,
    Do we actually possess the data?
    Do we have albedo measurements in relation to height?
    Is your figure (170 W/m2) at the height at which there is 1 bar pressure, or is an approximation of insolation at the surface?

  50. Yes indeed, Dr Spencer, the implications of what the natural laboratories of Venus and elsewhere tell us, have revolutionized atmospheric physics. Though many have yet to realise this. GHE, my foot! BK

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