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By William and Gavin

On Thursday March 8th, the UK TV Channel 4 aired a programme titled “The Great Global Warming Swindle”. We were hoping for important revelations and final proof that we have all been hornswoggled by the climate Illuminati, but it just repeated the usual specious claims we hear all the time. We feel swindled. Indeed we are not the only ones: Carl Wunsch (who was a surprise addition to the cast) was apparently misled into thinking this was going to be a balanced look at the issues (the producers have a history of doing this), but who found himself put into a very different context indeed [Update: a full letter from Wunsch appears as comment 109 on this post]

So what did they have to say for themselves?

CO2 doesn’t match the temperature record over the 20th C. True but not relevant, because it isn’t supposed to. The programme spent a long time agonising over what they presented as a sharp temperature fall for 4 decades from 1940 to 1980 (incidentally their graph looks rather odd and may have been carefully selected; on a more usual (and sourced!) plot the “4 decades of cooling” is rather less evident). They presented this as a major flaw in the theory, which is deeply deceptive, because as they and their interviewees must know, the 40-70 cooling type period is readily explained, in that the GCMs are quite happy to reproduce it, as largely caused by sulphate aerosols. See this for a wiki-pic, for example; or (all together now) the IPCC TAR SPM fig 4; or more up-to-date AR4 fig 4. So… they are lying to us by omission.

The troposphere should warm faster than the sfc, say the models and basic theory. As indeed it does – unless you’re wedded to the multiply-corrected Spencer+Christy version of the MSU series. Christy (naturally enough) features in this section, though he seems to have forgotten the US CCSP report, and the executive summary which he authored says Previously reported discrepancies between the amount of warming near the surface and higher in the atmosphere have been used to challenge the reliability of climate models and the reality of human induced global warming. Specifically, surface data showed substantial global-average warming, while early versions of satellite and radiosonde data showed little or no warming above the surface. This significant discrepancy no longer exists because errors in the satellite and radiosonde data have been identified and corrected. New data sets have also been developed that do not show such discrepancies. See-also previous RC posts.

Temperature leads CO2 by 800 years in the ice cores. Not quite as true as they said, but basically correct; however they misinterpret it. The way they said this you would have thought that T and CO2 are anti-correlated; but if you overlay the full 400/800 kyr of ice core record, you can’t even see the lag because its so small. The correct interpretation of this is well known: that there is a T-CO2 feedback: see RC again for more.

All the previous parts of the programme were leading up to “so if it isn’t CO2, what is it?” to which their answer is “solar”. The section was curiously weak, and largely lead by pictures of people on beaches. It was somewhat surprising that they didn’t feature Svensmark at all; other stuff we’ve commented on before. Note that the graph they used as “proof” of the excellent solar-T connection turns out to have some problems: see figure 1c of Damon and Laut.

Along the way the programme ticked off most of the other obligatory skeptic talking points: even down to Medieval English vineyards and that old favourite, volcanoes emitting more CO2 than humans.

It ended with politics, with a segment blaming the lack of African development on the environmental movement. We don’t want to get into the politics, but should point out what the programme didn’t: that Kyoto exempts developing nations.

[Also: other discussion at InTheGreen, Stoat, The Guardian and
Media lens.]
[Update: What Martin Durkin really thinks!]
[Update for our german readers: A german version of the “swindle” film was shown on June 11 on German TV (RTL); here is a german commentary by stefan.]

558 Responses to “Swindled!”

  1. 351
    BarbieDoll Moment says:

    “Seems to me that if we can causing warming with CO2 and cooling with sulphates, we should be able to set just about any temperature we want. “

    Those are two different issues. CO2 decreases the window space available
    in the atmosphere for reradiated energy to escape off into space.

    Sulfates, like aersols, cause light scattering, an albedo effect.

    Cumberland Sulfur Emissions

    …”Small particles are formed in plumes from coal-fired power plants when SO2 is oxidized to sulfate (SO4-2) aerosol particles. In the eastern United States in particular, these sulfate particles contribute significantly to the concentration of very fine particle matter (PM2.5), that causes reductions in visibility because of its light-scattering properties (Table 1). On the very haziest days, sulfate aerosols may contribute more than 80 percent of the visibility reduction in the Tennessee Valley region.”…

    GOES-8 Sounder Profile Retrieval Information
    Radiative Transfer Equation Basic Principles
    …”The weighting function, the derivative of transmittance with respect to height (pressure), specifies the relative contribution each atmospheric layer makes to the radiation emitted to space and thereby determines those regions of the atmosphere which are sensed from space at this wavelength.”..

    …” Around the broader CO2 and H20 absorption bands, vertical profiles of atmospheric parameters can be derived. Sampling the center of the absorption band yields radiation from the upper levels of the atmosphere (e.g., radiation from below has already been absorbed by the atmospheric gas). Sampling away from the center of the absorption band yields radiation from successively lower levels of the atmosphere. In the wings of the absorption band are the windows that view to the bottom of the atmosphere. Thus, as a spectral band is moved toward the center of the absorption band, the radiation brightness temperature decreases due to the decrease of temperature with altitude in the lower atmosphere. “…

    …”Because the concentration of CO2 is nearly uniform in the atmosphere, the weighting functions specific to the CO2 absorbing bands show little variation with location. However, water vapor concentrations vary greatly from one location to another. The non-uniform concentration of water vapor in the atmosphere will cause the weighting functions specific to the H2O absorbing bands to vary by location. “…

  2. 352
    George says:

    A reference to a paper by Notholt et al “Influence of tropospheric SO2 emissions on particle formation and the stratospheric humidity” from GEOPHYSICAL RESEARCH LETTERS is making the rounds in some of the debates on global warming.

    It’s being used to counter the argument that SO2 aerosols caused the relatively cool period from 1940 to 1960. And to show that the Global Warming Mafia can’t even get their SO2 effects right.

    To me it seems to actually be saying that in addition to what everyone says about SO2 causing cooling it also increases the transport of water vapour into the stratosphere, augmenting water vapour’s warming effect.

    Does anyone have knowledge of this paper and it’s relevance to global warming? Does it have any impact on the models in use?


  3. 353
    Hank Roberts says:

    Uh, four year old newspaper article about a story that’s been debunked here — and your point is?

  4. 354
    Jeff says:

    lolz at GW nutters. I wonder how many of you were this critical about Al Gores inconsistancys. Let the debate begin but let it begin in an open and honest manner. The point of the movie is debunk claims by Al Gore and the GW-ists. It does a great job at exposeing some bad claims that should have been delt with by Gore.

  5. 355
    guthrie says:

    Bob- only if we have vast amounts of energy and material to spare. How do you propose to create the vast cloud of sulphates, let alone increase or decrease the amount of CO2 in the atmosphere by millions of tons every year?

    Joe, thats an old, sensationalist article, covering the North atlantic. Even if it were to happen, (and climatologists currently think the catastrophic scenario is very unlikely.) it would only really affect Norther Europe. The rest of the world would still be warmer.

  6. 356
    angus says:

    Please forgive my ignorance again, is there a model which matches the T/CO2 ice core record and what happens to it if todays CO2 level is suddenly injected at the end of the last ice age?

  7. 357
    Leo says:

    So. Tell me if I�ve got this right. The man-in-the-pub, one-stop-shop, bullet-point explanation is this:

    – CO2 is one of a number of “greenhouse” gases, which are known to act, with the stimulus of energy from sunlight, to make the planet warmer than it would be through the action of sunlight alone

    – Ice core data shows the concentration of CO2 in the atmosphere rising and falling naturally over time (perhaps due largely to warming and cooling of the oceans amongst other factors, but who cares?).

    – Ice core data also shows that CO2 concentration is currently on an upward trend, and is at its highest level for about 330,000 years

    – Very recently it has increased more dramatically than would be consistent with this natural variation

    – This jump not only coincides with industrialisation and the known increase in combustion of fossil fuels

    but it has been demonstrated that fossil fuels are to blame by measuring decayed radioactive carbon isotopes in the atmosphere. (?)
    ( Reference?)

    – Theoretically, it would be anticipated that the Greenhouse Effect would cause this high combined level of CO2 to have a marked effect on global temperature.

    – At the same time it has been observed that global temperatures, whilst apparently at a peak or plateau in the long term

    are in fact increasing dramatically in the short term

    – Models incorporating all known effects on global temperature suggest that the current temperature increase is indeed linked to increased greenhouse gases.

    How am I doing?

    So Durkin is wrong to attack Gore’s suggestion that the Vostok core T and CO2 records show a cause-and-effect relationship because that’s not the point. The point is that our output of CO2 when coupled with an already high background level is reaching unprecedented concentrations. Which, from all that we know, would suggest a greatly increased greenhouse warming. The likely effects of which are a whole different can of worms.

    He is also wrong to try and overshadow the importance of CO2 with discredited theories about cloud formation, not least because even if it were true it would be beyond our control, whilst CO2 emissions, however small their effect, are definitely within it.

    Is he wrong to urge caution when relying on a model for that crucial last link?
    Is he really wrong to throw the debate so harshly into the public domain, however crassly?
    It would be dreadful to become complacent we have the answer only to discover global warming is being caused by another factor we have failed to mitigate.

    Is he wrong to urge caution in making sweeping global policies that could make life impossible for the world’s most vulnerable people?

    Why can’t mud huts have chimneys anyhow?

  8. 358
    angus says:

    Leo, I think both Durkin and Dole were both guilty of “tabloid science”, aiming to sway the masses. Also, in an unprecented situation, a model is all we have to go on when predicting the future. I think if this went to a court of law, a jury would find the AGW case proved beyond reasonable doubt. Hey, there’s a thought lets get the lawyers involved!

  9. 359
    Matthew Lemin says:

    Hopefully a simple question from a layman!
    To what extent is the change in Total Solar Irradiation (TSI) taken into account in the models used for the IPCC report?

    Follow on questions:
    Do the models assume a static constant for solar forcing?
    Or do they assume a change in line with projections of future sunsport, TSI and magnetic field flux in the sun?

    I have in mind Willson’s suggestion that TSI has changed by 0.05% a decade since 1978 and that other data points to this having been the continuation of a trend over the last 100 years.

    Also considering the Carbon 14 data which suggests that solar activity is currently at a 1,000 year high.
    (graph on right hand panel)

    If the models fail to take into account that we may have been in a long-run period of continued increases in solar activity, and that the activity may affect global temperatures, is there not a danger that we are over-estimating the influence of greenhouse gas emissions simply because we have under-estimated the effect of solar forcing?

    [Response: The most recent assessments of the satellite data show no trend since 1979 ( ). 14C can’t be used over the last 150 years due to contamination by fossil fuel use (which reduces the 14C content of the atmosphere significantly) and the bomb tests in the 1950’s (which increased it). Cosmic Ray trends over the last 50 years are non-existent. There are 11 year cycles that are clear though. Models use the best estimates of how TSI has changes (including the different changes in different parts of the spectrum), but when you stack it up against greenhouse gases, the trends would have to be about 10 times as large to even be comparable. – gavin]

  10. 360
    Hank Roberts says:

    > Politically
    > Is he wrong to urge caution in making sweeping global policies that could
    > make life impossible for the world’s most vulnerable people?

    Certainly not, and that’s why Gore has been urging caution for a long time now.

    It’s what we did, mostly out of ignorance, by using fossil fuel so fast for fifty years. I”m not talking about ‘global warming’ — I’m talking about changing the oceans so the plankton, base of the food chain and primary photosynthesizers, are damaged.

    It’s like smoking knowing you’re putting the people around you at risk from combustion byproducts — immoral, and stupid.

  11. 361
    angus says:

    excuse my typo, Dole for Gore, I would doubt they are interchangeable on this issue. I was somewhat distracted as my daughter just told me she was going to have a baby, suddenly I am even more convinced that we can’t sit by and see what happens.

  12. 362

    [[Seems to me that if we can causing warming with CO2 and cooling with sulphates, we should be able to set just about any temperature we want. ]]

    Technically that’s true. But both have other consequences which are not so good. Sulfates hurt human health and carbon dioxide acidifies the oceans. In the long run it’s best to stop putting both into the atmosphere.

  13. 363

    [[the Global Warming Mafia can’t even get their SO2 effects right.]]

    Youse keeps talkin’ like dat, and we’re gonna have to take youse for a global warmin’ ride.

    One paper doth not a consensus make. If he (or she, or they) has/have good results, then they will be accepted if others can reproduce them. Otherwise, they won’t be.

  14. 364

    Angus, congratulations to you and your daughter.

  15. 365
    David B. Benson says:

    Re #356: angus — Yes. The Archer/Ganopolski paper has been commented upon at least twice in different, recent threads. Roughly, if humans can limit cardon exhaust into the atmosphere to a mere 1000 Gt (300 Gt so far) then the climate will finally return to normal in about 100,000–150,000 years.

    Re #357: leo — You asked how you were doing so far. Looks to me that you have the jist of the science, but I’m only a fairly recent amateur at climatology…

  16. 366
  17. 367
    Hank Roberts says:

    I can’t believe the Daily Mail quoted Dr Lindzen correctly, and asked them to recheck.

    They attribute this to Dr. Lindzen:

    > “a very gently warming trend, …. this minor trend could have easily have been
    > caused by irregularities such as volcanic eruptions …”

    I know volcanos are warm — but the notion they’re warming the Earth seems contrary to observations.

  18. 368
    moira says:

    What the BBC think of TGGWS. The Now Show, 16/3/07 BBC Radio 4

  19. 369
    J.C.H says:

    From Lindzen’s rebuke:

    “… Stern also refers to ‘significant melting of and an acceleration of ice floes’ near the coast of Greenland because of global warming.

    Yet several reputable scientific studies have shown that the mass of the Greenland ice sheet is actually expanding, while Stern also fails to note that the temperature of Greenland is now lower than it was in 1940 and little changed from the first measurements in the 1780s. …”

    I’m far from being an MIT physicist, but one could easily have both expansion of the icecap and expansion of the ice melt; as in, it snows on top a whole bunch and it melts on the edges a whole bunch.

    If it’s warming, could it also be snowing a lot more in certain places? Maybe it’s snowing more on top of the Greenland icecap, which is a bit higher than the coastlines of Greenland, which, therefore, could be a bit warmer because they’re down lower – kind of like an island with snow-capped peaks and bikinis on the peaks on the beaches. In splendor, such peaks can coexist – I think?

  20. 370
    Mickey says:

    There seems to be more “faith” in Global Warming than science. It is interesting that GW advocates totally discount a total picture of many related theories and focus on only the CO2 issue. By simplifying the data and cherry picking you end up complicating the issue. The other major flaw in the GW frenzy is your reluctance for peer review. If you don’t respect the professional input of other scientists then there is legitimate reason to assume you also have no confidence in your theories.
    You certainly don’t have exclusive knowledge here.

  21. 371
    Hank Roberts says:


  22. 372
    Bob says:

    Now I am just wondering, if sulphate pollution from the 1940’s to the 1970’s caused global cooling during that period, but was fixed with Clean Air acts of the 1970’s, why isn’t pollution from China, India, Mexico, Russia, and other parts of the world, which have no clean air acts, doing the same ?

  23. 373
    Dick Veldkamp says:

    Re: #370 (Mickey)

    Just out of curiosity, WHY in the world do you believe that:
    – there’s more faith than science in GW?
    – scientists discount other theories just like that without examining them?
    – they are cherry picking data?
    – they are afraid of peer review?
    – they have no confidence in their own theory?

    Before you make claims such as these, you’d better take a couple of hours to read up on the evidence. Use this site. If you think that’s too technical, check out Wikipedia. Or
    go here for excellent answers:

  24. 374
    Bladernr1001 says:


    Judging from this comment board I would have to conclude that the debate over global warming is not over.

    Any time I see people like polititians and scientists on the public dole saying anything….I look at it with a jaundiced eye.

  25. 375
    Hank Roberts says:

    >372 Bob
    Because in the 1940-1970 period, the total fossil fuels so far burned was less than half today’s total; the CO2 increase had started at the time, but look at the pattern:

    Aerosols work fast and go away fairly fast; after the Clean Air Act reduced those in the 1970s, they fell out of the atmosphere.

    But the CO2 put into the atmosphere during the same time span persists — it stays up much longer.

    Once a given amount of CO2 increase (above what nature can remove at the same pace) happens, we get the period of increasing temperature until the planet reaches equilibrium.

    During 1940-1970, when fossil fuel began being burned in large amounts, the aerosols acted right away — reflecting some solar energy; the CO2 was only starting to increase.

    The heating from thatt’s happening now — the heating committed to by the fossil fuel use up to 1970 goes on for decades; the effect we experience is — probably — slowed down by the second round of aerosols, acting now, but it’s acting on a very different background.

    In the time up to the 1940s, we hadn’t much overwhelmed the planet’s annual ability to recycle CO2.

    That’s an amateur reader’s explanation; stand by for someone with real science credentials to, I hope, correct and improve my understanding. I post what I think, expecting to learn better thanks to the scientists.

  26. 376
    BarbieDoll Moment says:

    RE: “Notholt et al “Influence of tropospheric SO2 emissions on particle formation and the stratospheric humidity”

    No offense meant at all, but I am not sure if I even understand any of the reasoning you cite or mention because it seems to fails the basic science understandings to date.

    The link for the paper for which you spoke.

    Influence of tropospheric SO2 emissions on particle formation and the stratospheric humidity
    J Notholt et al
    Geophysical Research Letters 32 (7), 07810 (09 Apr 2005)
    …”Here we present a mechanism that would link increasing anthropogenic SO2 emissions in southern and eastern Asia with an increase in stratospheric water.”…”Our model calculations suggest that such a mechanism could increase the amount of water that entered the stratosphere in the condensed phase by up to 0.5 ppmv from 1950â??2000.”

    Other papers that discuss the modeling and or science of the matter.

    Volcanic Hazards: Gases (sulfur dioxide, carbon dioxide, hyrdogen chloride, and hydrogen fluoride) U.S. Department of the Interior, U.S. Geological Survey 10 January 2006
    “The most abundant gas typically released into the atmosphere from volcanic systems is water vapor (H20), followed by carbon dioxide (C02) and sulfur dioxide (S02).”…

    Global Cooling After the Eruption of Mount Pinatubo: A Test of Climate Feedback by Water Vapor
    Science, Volume 296, Issue 5568, pp. 727-730 (2002) Soden, Brian J.; Wetherald, Richard T.; Stenchikov, Georgiy L.; Robock, Alan…296..727S&db_key=PHY&data_type=HTML&format=&high=42d4f8714c06778
    …”Here, we first highlight the success of the model in reproducing the observed drying after the volcanic eruption. Then, by comparing model simulations with and without water vapor feedback, we demonstrate the importance of the atmospheric drying in amplifying the temperature change and show that, without the strong positive feedback from water vapor, the model is unable to reproduce the observed cooling. “…

    Two-decadal aerosol trends as a likely explanation of the global dimming/brightening transition
    Geophysical Research Letters 33 (15), 15806 (2006)
    …”We show that the inter-annual trend in solar radiation between 1980 and 2000 mirrors the trend in primary emissions of SO2 and black carbon, which together contribute about one-third of global average aerosol optical depth. “…

    Climate simulations for 1880-2003 with GISS modelE
    J Hansen et al.
    ArXiv Physics e-prints, (Oct 2006)

    …”Satellite observations of the planetary radiation budget perturbation following the 1991 Mount Pinatubo eruption [Wong et al., 2004] provide a strong constraint on the aerosol forcing for that volcano [Figure 11 in Efficacy, 2005]. That comparison suggests that the above relationship between aerosol optical thickness and climate forcing is accurate within about 20%.The stratospheric aerosol forcing becomes more uncertain toward earlier times. We estimate the uncertainty as increasing from ±20% for Pinatubo to ±50% for Krakatau.At intervals be tween large eruptions prior to the satellite era, when small eruptions could have escaped detection, there was a minimum uncertainty ~0.5 W/m2 in the aerosol forcing. Stratospheric aerosol optical thickness was zero in our climate model control run. Our future control runs will include stratospheric aerosols with Ï? (λ = 0.55μm) = 0.0125, the mean visible optical thickness for 1850-2000, with the rationale that this is a better estimate of the long-term mean stratospheric aerosol optical depth than is the use of zero aerosols. We recommend (Appendix A) that other researchers include such a mean aerosol amount in control runs used as spin-ups for transient simulations, because the deep ocean then approaches a more appropriate equilibrium temperature. Omission of this forcing from the control run alters the rate of ocean heat storage in transient climate simulations. Use of the mean aerosol optical depth in the control run also would have reduced the modeled Krakatau cooling by almost 10%, for an appropriate reason, bringing model and observations into better agreement (see section 4.2).”…”The uncertainty in the net forcing is dominated by the uncertainty in the aerosol forcing, which we suggested above to be at least 50%. Even with the most optimistic assessment of our understanding of the forcings, we must conclude that the net forcing is uncertain by ~ 1 W/m2. Accepting these forcing estimates at face value implies that the net forcing is uncertain by about a factor of three, primarily because of the absence of accurate measurements of the aerosol direct and indirect forcings”….”Overall, we conclude that there is good qualitative and semi-quantitative agreement between simulated radiation-related quantities and observations, e.g., with the phenomenon of â??global dimmingâ?? [Stanhill and Cohen, 2001; Liepert, 2002; Cohen et al., 2004], the reduction of solar radiation incident on the surface. Our model results indicate that dimming is due primarily to absorbing aerosols and secondarily to the aerosol indirect effect on clouds. The same forcings are principal causes of a decrease in the amplitude of the diurnal cycle of surface air temperature, such a decrease being in accord with observational evidence [Karl et al., 1993]. The model yields a significant increase of global mean cloud cover, largely due to the aerosol indirect effect, but the local effect does not generally exceed local unforced variability in the model.”…

    Volcanoes and climate: Krakatoa’s signature persists in the ocean.
    P J Gleckler et al.
    Nature. 439 (7077), 675 (09 Feb 2006)
    …”Volcanically induced cooling of the ocean surface penetrated into deeper layers, where it persisted for decades after the event. “….

    Significant decadal-scale impact of volcanic eruptions on sea level and ocean heat content.
    John A Church, Neil J White, and Julie M Arblaster
    Nature. 438 (7064), 74-7 (03 Nov 2005)
    …”Here we use observations of ocean heat content and a set of climate simulations to show that large volcanic eruptions result in rapid reductions in ocean heat content and global mean sea level. “…

    Ocean Heat Content Variability in the Second Half of the 20th Century: Results from the IPCC AR4 Simulations.
    K Achutarao et al.
    AGU Fall Meeting Abstracts, 4 (Dec 2006)
    …”We specifically examine the role of varying observational coverage and the inclusion of volcanoes in the simulated variability of ocean temperatures. ”

    2006 Was Earth’s Fifth Warmest Year
    NASA GISS: Research News, (08 Feb 2007)
    …”Blue semi-circles mark La Niñas, red rectangles mark El Niños, and green triangles mark large volcanoes.”…

    Solar influence on climate during the past millennium: Results from transient simulations with the NCAR Climate System Model
    Caspar Ammann et al.
    Proceedings of the National Academy of Sciences 104 (10), 3713 (06 Mar 2007)
    …”High scaling of the solar irradiance leads to model temperatures by the end of the century that are only marginally (0.1°C) warmer than those from the low and medium scaled forcing. This finding suggests that, while solar irradiance changes and explosive volcanism were the dominant forcings in preindustrial times, their combined role has been changing over the past century. Although these natural forcing factors could be responsible for some modification of the decadal structure over the 20th century, they only played a minor role in the most recent warming.”…

    Southern Ocean warming due to human influence
    Geophysical Research Letters 33 (19), L19701 (2006)
    …”I also show that climate models that do not include volcanic aerosols produce mid-depth Southern Ocean warming that is nearly double that produced by climate models that do include volcanic aerosols. This implies that the full effect of human-induced warming of the Southern Ocean may yet to be realized. ”

    Here are additional papers

    Private Library Seasonality of Volcanoes/Climate/Water
    34 abstracts

    Some of my other libraries with extensive scientific papers on the subject(s) matter

    volcanoes and climate

    Volcanic Activity

    Climate Sciences

    Intergovernmental Panel on Climate Change (IPCC)


  27. 377
    Angus says:

    I have read the Archer Ganopolski paper. They say in para 16 that they the amplyfing role of natural CO2 in deglaciations is poorly understood, does this mean that the models used do not simulate oscillations in temp and CO2 levels as they come down from the maximum? Again a dumb question, but isn’t the key to understanding the anthoprogengic addition of CO2, is to model and understand the natural process it disrupts?

  28. 378
    Manboy says:

    Re #370,

    I’m not sure you know what you’re on about. “Reluctance” for peer review ?

    Such as IPCC ?

    Such as scientific research done on the matter and published in peer-reviewed journals ?

    Such as the Arctic Climate Impact Assessment ?

    I’d state the opposite : It is infact the DENIALISTS who rely so much on “faith”. The studies on climate change are based on science. You don’t like it but that’s the way it is.

    You’re just taking the mickey (pun intended) out of folks who have an serious interest in CC, aren’t you ?

  29. 379
    Geoff Wexler says:

    IPACACC (UN’s International Panel against Cheating about Climate Change)

    Initial agenda:
    1. The identification of spin, cheating etc.
    1. Identification and definition of the forcing agents e.g the American Petrol Inst. ,Exxon-Mobil, etc.
    2. The distinction between forcing agent and causation (for cheating).
    3. An attempt to solve The lead-lag problem i.e which occurs first the funding or the dodgy papers?
    4. The detection and attribution problems e.g. the detection of input from Exxon and estimate of its significance.

    Seriously, the CO2 emitters have every right to highlight skeptical views but they if they do so covertly they should not complain when it is exposed. The C4 programme sneered at those who refer to Exxon funding while at the same time concealing that one of the graphs was funded by them (the one by Soon which I mentioned above). That graph shows a net coolng between 1940 and 2000 for the Antarctic. Of course the Exxon connection is strictly irrelevant except that it was implicitly denied by C4. I am still awaiting comment from the experts as to its status.

  30. 380
    David B. Benson says:

    Re #377: Angus — Archer & Ganolpolski used a fairly simple, but robust, model of global climate due to Paillard in which only temperature and ice volume occur. They treat carbon dioxide entirely as a forcing, except for the deep ocean contribution. This latter is just a matter of adjusting the parameters in the Paillard model.

    One possible source/sink of up to 60 ppm of carbon dioxide during the transition through an interglacial from one stade to the next is coral reefs. Archer & Ganolpolski state, again in paragraph [16], that including such effects would prolong the long-term climate impact.

    I believe the results are good enough to suggest long-term impacts. However, I do not view the work as precise enough to state, for eample, that the maximum global temperature increase from adding 1000 Gt of caron will be, say, 3 K. For that a more sophisticated approach to modeling carbon dioxide would be required.

  31. 381
    Eric says:

    Well it’s been a funny kind of month. Every day I wake up to the Radio 4 news. I listen and – yes – there it is. Someone has mentioned the word(s) ‘environment’ or ‘green’ or ‘carbon footprint’ or ‘global warming’. I fear that I shall scream if I hear them again. Some politician tells us how additional taxes will help sort the problem and a friendly Greenpeace representative tells us we are all doomed. The message is always the same. Why is it always presented as a dead certainty? Where is the balanced scientific discussion?

    Then ….10 days ago – a wonderfully refreshing program on Channel 4. Biased? Who cares. It has the desired effect. Suddenly everyone wants to talk about the Science.

    At this point, as a caring and concerned and member of the human race, with no inside knowledge on these matters, I felt I ought to do something about my lack of expertise in this area. I set myself the task of the reading the newspapers and surfing the internet.

    The experts don’t seem to agree with each other. The only way I am going to be able to work this one out is to get hold of the original data and sort it out myself. I spend hours surfing but it is so difficult to locate the data sets. Time for bed.

    It is now Saturday morning. There is a discussion on the radio. The nice Greenpeace man calls the C4 program “Junk Science” not like the really informative articles in the “Independent” newspaper. So it’s back to the Independent for some independent advice. I get out my crumpled copy dated 14th March. I am immediately struck by the 2 central graphs concerning Temperature and Solar Activity. How could C4 have got it so wrong? The 2 graphs look nothing like each other! Lets have a look at the Peter Laut paper (Journal of Atmspheric and Solar-Terrestrial Physics 65 – 2003) – Yep, those last 2 points are wrong, the solar cycle lengths should be 10.61 and 10.59. Back to the Damon and Laut article (2004) to see the effect on the graph. Let’s compare the original graph with the updated graph (c)….(a), (c), (a), (c).. .Just a minute, aren’t they very similar apart from the flat bit at the end. Hang on a minute, what about those 2 entirely different looking graphs in the Independent? After a long hard look I’ve spotted it. Steve Connor at the Independent has decided to change the temperature scale on the 2nd graph thus creating the illusion of dissimilarity. I wonder what the 2nd graph would look like with the original scales of the 1st graph? An unfortunate oversight I am sure. But wait, the exaggeration is made to look even worse. While the Solar activity is having a rest on its plateau we are reminded of the “Roadrunner” temperature which zooms past, onwards and upwards, for a further 20 years. Bit difficult to compare the two sets of data here. Never mind, so long as we are left with the correct final impression that’s all that counts. So the graphs are unfortunate, what about the words? Steve Connor writes next to these 2 graphs “There is now no such correlation between the 2 sets of data, which undermines another key ‘fact’ “. O.K. let’s see if we can run the updated data (well that is my best attempts at determining the updated data – it is not that easy for Joe Public to find!) through a basic stats package. Oh dear, it would appear that the 2 sets of data have a correlation of about 0.65 with a p value of 0.023, i.e. somewhere between “significant” and “highly significant”. Right…somewhat different from “no such correlation between the two data sets”.

    So where does that leave me? I clearly can’t trust C4 i.e. Television. I clearly can’t trust the Independent i.e. Newspapers. I clearly can’t trust the “experts” who disagree with each other. I most certainly will not trust the utterances of any politician or any group with a vested interest. I guess I’ve got to work it out for myself. Well, funnily enough I think I have. You see, when I go into a crowded smoky room my body reacts to the carbon floating in the atmosphere. Also, I have noticed that at night time, when the big yellow thing in the sky has gone to sleep my body reacts again and I feel chilly. My wild guess is that probably both the Sun and the contents of the atmosphere have an effect upon temperature. I do hope I’ve got it right.

  32. 382
    Hank Roberts says:

    I do hope you will consider the possibility that you have got it completely wrong.

    Have you read the AIP history page, for example, or any of the other sources linked at the right side of the main page?
    Done the math?

    Correlated fossil fuel burned per year, CO2 change
    and aerosol change
    with that set of temperature charts,
    Compare rather than lump together the early and later times — the lines diverge where the predicted warming shows up.

    Please show your work if it’s your own, or cite it if you’re borrowing others’ work, eh?

  33. 383
    Ian says:

    Eric (#381),

    I think your willingness to track down and look at the data and science itself is great! Keep it up, there should be more people like you.

    From your description, it sounds as if you ran a correlation to test for linear trend over the whole data range, in which case a significant coefficient isn’t surprising. The crucial thing here is that more advanced models, especially GCMs, aren’t simple linear models – they match the curve of observed temperature, and will even reproduce temporal and spatial patterns, in response to observed changes in forcings (e.g., solar irradiance, CO2, volcanic eruptions, etc., etc.). That’s why a divergence between solar measures and temperature over the last few decades is meaningful, and doesn’t help the solar explanation.

  34. 384
    JonL says:

    In your introduction to this Blog you say,

    ‘…but if you overlay the full 400/800 kyr of ice core record, you can’t even see the lag because its (sic) so small. The correct interpretation of this is well known: that there is a T-CO2 feedback…’

    So, the (800ish)-year lag is totally insignificant when viewed from a larger time scale? (The ‘T-CO2 feedback’ appears causally impossible given this lag.) I have read the rather good article on this site which tackles this counter-intuitive anomaly and have found in it a lot of ‘coulds’ and ‘mights’, but a general admission that it is an unknown It also notes that the ‘first cause’ of a new (interglacial) warming trend would probably be variations in solar radiation or changes in ocean behaviour. It is unclear on this, as it is on other points. The solar radiation ‘forcing’ issue in general I suppose is one of those areas of uncertainty.

    But the lag does exist, then, even if it is here dismissed as insignificant when viewed in a larger time scale. As you put it, the ‘correct’ interpretation is the – well – correct one, I guess!

    Fine, I am not trolling around here. I have a genuine interest, as all responsible people do, and I don’t want to ‘get into it’ with science journalists or climate-studiers who seem to spend most their lives rebutting people they (rather hastily in my view) adjudge ‘deniers’, if this site is anything to go by, and have therefore become rather good at it.

    I have just a couple of concerns, though: If we can ignore an 800-year lag between CO2 and temperature rise as insignificant when reviewed on a geological time scale – regarding it as the beginning of a 5000-year cycle during which CO2 takes over the warming process (at c.4200 years) – then why can’t we ignore recent tiny temperature variations on similar grounds? Or, why can’t we see current trends as merely the beginning of a new 5000-year interglacial cycle – which began some time ago, during which relatively small contributions from human activities will merely foreshorten the 800-year lag (by how much is another unknown/unknowable, it seems)? And why can’t we assume that it hasn’t been kick-started by solar radiation or some other ‘forcing agent’ just as it has in the past?

    I can comprehend the notion that a higher CO2 level might conceivably have ‘kick-started’ this latest trend itself. But apparently this would be remarkable as it has never been proved that CO2 actually could ever act as a ‘kick-starter’ for such a trend in the first place. Maybe this last point can be clarified for me. I am sure someone who is much more informed will have a wonderful answer to all these no-doubt silly reactions (which are really more about method than topic). I look forward to reading it.

    Lastly, although it is self-evident that future generations will have to ‘pay the price’ for a warming planet regardless of what caused it, what I do object to is that we mere ‘civvies’ are expected to pay for all this one way or another in any case right now; that it is some kind of ‘moral responsibility’. It really is not that simple. And for myself, a natural sceptic, I suspect we will pay inevitably and soon, but far more in treasure than in pain, although the two are never mutually exclusive, given the current political ‘climate’. That is not to say that there are not people in the developing world who could conceivably pay in pain – if they aren’t already – if the western governments proclaim they shall not ‘develop’ (ie: make electricity and create sanitation for future generations using all means possible).

    But I still appreciate what you at realclimate are trying to do – keep ordinary people reliably informed about the state of the research, and engage in some debate, even if it is from the position of a particular mindset (that AGW is completely irrefutable – something with which I am bound to disagree. But, of course, I do agree that GW is completely irrefutable – just for the record).

  35. 385
  36. 386
    Hank Roberts says:

    A perhaps useful definition, found here:

    In a speech in 1913, Cassius J. Keyser (J. does not stand for Julius) explained:

    “But does not the lawyer sometimes arrive at correct conclusions? Undoubtedly he does sometimes, and, what may seem yet more astonishing, so does your historian and even your sociologist, and that without the help of accident. When this happens, however, when these students arrive, I do not say at truth, for that may be by lucky accident or happy chance or a kind of intuition, but when they arrive at conclusions that are correct, then that is because they have been for the moment in all literalness acting the part of mathematician. I do not say this for the aggrandizement of mathematics.”

  37. 387
    proffate says:

    What’s a “scientist.” anyway? Are acolytes required to undergo arcane rituals in order to gain access to the mysteries of “science”?

    Nope. It’s all out there for anyone who wants to look it up.

    So I looked it up. My conclusion was that the global warming bruhaha was political, rather than scientific.

    When in doubt, follow the money. Tons of cash is going to researchers who put “warming” into the descriptions of their research.

    What’s worse is the “cure.” A Global Warming Tax is being proposed for anyone who has the audacity to use energy for heating, cooling, driving or any other activity associated with life in an industrialized nation. If global warming guilt could be translated into cash, somebody is going to make a bundle!

    This money would go to an unelected body who could pay themselves any salary they saw fit, while claiming “nonprofit” status.

    My background is in advertising/marketing, rather than science (although I can claim a 99 percentile on the ACT test). So I’m able to recognize a moneygrubbing scam when I see one.

    Global warming is that scam. Guard your wallets!

  38. 388
    Gavin McP says:

    In case you didn’t catch it on the other thread, Chris Merchant of Edinburgh University offers an eloquent rebuttal to some of the claims made in Durkin’s film.

    (115 MB download)

  39. 389
    Mike Donald says:

    That ACT. Does that stand for Associated Conservatives of Texas or Alliance for Cannabis Therapeutics?

    I dunno.


  40. 390
    Gavin McP says:

    #388: Sorry to correct my own post – I should point out that Merchant appears to have made an error in his analysis of the solar-T curve (as noted here, based on William Connelly’s analysis here).

  41. 391
    Paul Swanson says:

    Where did the carbon in coal and oil come from? There can be no denying that it came from atmospheric CO2. If up until recent times the biosphere was a net sink for carbon, then a reversal of that process just gets us back to were we started. The real issue is how the perturbation of current levels effects the ecosystem, and what will be new steady state. We will adapt; that is what we do best. Adapting to change is why we are all not trilobites.

    p.s. Would have it been ethical to prevent an ice age?

  42. 392

    [[The message is always the same. Why is it always presented as a dead certainty?]]

    Probably because, at this point, it’s pretty much a dead certainty.

  43. 393

    [[So I looked it up. My conclusion was that the global warming bruhaha was political, rather than scientific.]]

    You can’t have looked very far. Did you read any articles in peer-reviewed journals, such as Science, Nature, the Journal of Geophysical Research, Geophysical Research Letters, or the Journal of Atmospheric Sciences? Did you learn all the science, say by going through Hougton’s “The Physics of Atmospheres” and working all the problems?


  44. 394

    [[ why can’t we assume that it hasn’t been kick-started by solar radiation or some other ‘forcing agent’ just as it has in the past?]]

    Because we’ve measured the isotope ratios and know that the new CO2 in the air is almost all from burning fossil fuels.

  45. 395

    [[Where did the carbon in coal and oil come from? There can be no denying that it came from atmospheric CO2. If up until recent times the biosphere was a net sink for carbon, then a reversal of that process just gets us back to were we started. The real issue is how the perturbation of current levels effects the ecosystem, and what will be new steady state. We will adapt; that is what we do best. Adapting to change is why we are all not trilobites.

    p.s. Would have it been ethical to prevent an ice age? ]]

    The end state is NOT the only thing that’s important! How we get there matters as well! The future Earth with 295 K mean global annual surface temperature and 75% ocean coverage may be a nice place, but if the transition is fast enough, it will completely disrupt our agriculture and our economy.

    Achieving 120 mph because you’re in an airplane taking off is good. Achieving 120 mph because you fell off the Empire State Building is bad.

  46. 396
  47. 397
    Hank Roberts says:

    PS — coming soon — don’t have time to hunt for a link for this, just flagging for contribs to consider if interesting

    Full Committee Hearing: Future of Coal
    Thursday, March 22, 2007
    02:30 PM
    Energy Committee Hearing Room – SD-366

    The purpose of the hearing is to receive testimony on the �Future of Coal� report recently published by the Massachusetts Institute of Technology.

  48. 398
    John L. McCormick says:

    RE # 397

    Hank, thanks for the heads up on the Senate Energy Committee hearing on the Future of Coal report.

    Excuse the long URL but it should take you to the Senate announcement of the hearing and a link to the report, which, IMO, is a fabulous piece of work and a must read.

  49. 399
    SomeBeans says:

    #390: Gavin McP
    Regarding Chris Merchant’s reconstruction of the solar-T curve. Doesn’t the 11 point moving average which forms the first step of the analysis give you the solar cycle length (or something proportional to it) from the sunspot number?

  50. 400
    James says:

    Re #391: [Where did the carbon in coal and oil come from? There can be no denying that it came from atmospheric CO2. If up until recent times the biosphere was a net sink for carbon, then a reversal of that process just gets us back to were we started.]

    I suppose that’s technically sort of correct, but what you’re not seeing is the timescale. About half a billion years ago (give or take) the Earth’s atmosphere had a lot of CO2 but no oxygen. (The sun was dimmer then, too.) Then the first photosynthesizing plants started taking CO2 and turning it into oxygen, in the process of which some died, and their bodies got buried and eventually turned into coal and oil. Likewise, some kinds of sea life use CO2 to build shells, which eventually turn into rocks. Since volcanos and such keep adding a bit more CO2, eventually you get an atmosphere which has a fairly constant small amount of CO2. Meanwhile, life has evolved to prosper in this sort of atmosphere, and the sun’s gotten warmer so the temperature stays comfortable.

    So over 500,000,000 years, the biosphere has gradually taken most of the CO2 out of the air, and turned it to coal and oil. Now humans are digging up all that fossil carbon, and putting it back in the atmosphere a million times faster than it came out. Burn it all, and we might indeed get back where we started, to a planet with lots of CO2 but no oxygen, and a warmer sun. Not a place most of us would want to live, even supposing we could.