Guest post by Christopher Monckton of Brenchley
Abstract
Global CO2 emissions per unit increase in atmospheric CO2 concentration provide an independent constraint on climate sensitivity over the timescale of the available data (1960-2008), suggesting that, in the short term and perhaps also in the long, climate sensitivity may lie below the values found in the general-circulation models relied upon by the IPCC.
Introduction
The Intergovernmental Panel on Climate Change (IPCC, 2001, p. 358, Table 6.2), citing Myhre et al. (1998), takes the CO2 forcing ΔF as 5.35 times the logarithm of a proportionate change Cb/Ca in CO2 concentration, where Cais the unperturbed value. Warming ΔT is simply ΔF multiplied by some climate sensitivity parameter λ.
Projected 21st-century anthropogenic warming, as the mean of values on all six IPCC emissions scenarios, is 2.8 K (IPCC, 2007, table SPM.3: Annex, Table 0). Of this, 0.6 K is stated to be in the pipeline. Of the remaining 2.2 K, some 0.65 K is attributable to non-CO2 forcings, since the CO2 fraction of anthropogenic warming is 71% (the Annex explains the derivation). Thus the IPCC’s current implicit central estimate of the warming by 2100 that will be attributable solely to the CO2 we emit this century is only 1.56 K.
Projected CO2 concentration C2100 in 2100, the mean of the values on all six IPCC emissions scenarios, is 713 ppmv (Annex, Table 3), 345 ppmv above the 368 ppmv measured in 2000 (Conway & Tans, 2011). Therefore, the IPCC’s implicit climate-sensitivity parameter for the 21st century is 1.56 / [5.35 ln(713/368)], or 0.44 K W–1 m2. This value, adopted in (1), is half of the IPCC’s implicit equilibrium value 0.88 K W–1 m2 (derived in the Annex).
Global warming from 1960-2008
The IPCC’s implicit central estimate of CO2-driven warming from 1960-2008 is at (1):
The CO2 forcing coefficient 5.35 was given in Myhre et al. (1998). Initial and final CO2 concentrations were 316.9 and 385.6 ppmv respectively (Tans, 2012). Since the 0.46 K warming driven by the CO2 fraction is 71% of anthropogenic warming, use of the IPCC’s methods implies that, as a central estimate, all of the 0.66 K observed warming from 1960-2008 (taken as the linear trend on the data over the period in HadCRUt3, 2011) was anthropogenic. However, attribution between Man and nature remains problematic: an independent approach to constraining climate sensitivity produces a very different result.
An independent constraint on climate sensitivity
Since few non-linearities will obtrude at sub-centennial time-scales, to warm the Earth’s surface by 1 K the CO2 concentration in the atmosphere must increase by 345/1.56 = 223 ppmv K–1. From 1960-2008, the trend in the ratios of annual global CO2 emissions to annual increases in atmospheric CO2 concentrations does not differ significantly from zero (Fig. 1). The mean emissions/concentration-growth ratio over the period was 15.5 Gt CO2 ppmv–1, which, multiplied by 223 ppmv K–1, gives 3450 GTe CO2 K–1, the quantum of CO2 emissions necessary to raise global temperature by 1 K.
Figure 1. Near-zero trend in annual emissions/concentration-growth ratios, 1960-2008. Data and methods are described in the Annex. Spikes caused by volcanic eruptions are visible. Excluding effects of major eruptions makes little difference to the outcome.
Total global CO2 emissions from 1960-2008 were 975 Gte CO2 (Boden et al., 2011). Accordingly, CO2-driven warming expected over the period, by the present method, was 975 divided by 3450, or 0.28 K. Allowing for the non-CO2 fraction, some 0.40 K warming over the period, equivalent to 61% of observed warming, was anthropogenic, not inconsistent with the estimate in IPCC, 2007 that at least 50% of observed warming from 1950-2005 was anthropogenic. However, inconsistently with (1), this method yields a CO2-driven warming that is only 61% of the central estimate derived from the IPCC’s general-circulation models.
Implications
On the assumption that the coefficient in the CO2 forcing function, cut from 6.3 to 5.35 in Myhre et al. (1998), is now correct, one implication of the present result is that the climate-sensitivity parameter λ appropriate to a 50-year period is not 0.44 K W–1 m2, as the models suggest, but as little as 0.27 K W–1 m2. Since the value of the instantaneous or Planck sensitivity parameter λ0 is 0.31 KW–1 m2 (IPCC, 2007, p. 631 fn.), temperature feedbacks operating during the period of study may have been somewhat net-negative, rather than appreciably net-positive as implied by (1).
If feedbacks operating over the short to medium term are indeed net-negative, there is no warming in the pipeline from past emissions; in the rest of this century CO2-driven warming may be little more than 1 K; anthropogenic warming from all sources may be less than 1.5 K; and supra-centennial-scale warming may also be significantly less than currently projected. If so, all attempts at mitigation will prove cost-ineffective, and the cost of adaptation to future warming will be well below current estimates.
References
Boden, T., G. Marland, and R. Andres, 2011, Global CO2 Emissions from Fossil-Fuel Fossil-Fuel Burning, Cement Manufacture, and Gas Flaring: 1751-2008, available from http://cdiac.ornl.gov/ftp/ndp030/global.1751_2008.ems
Conway, T., & P. Tans, 2011, Recent trends in globally-averaged CO2 concentration, ww2.esrl.noaa.gov/gmd/ccgg/trends/global.html#global.
Garnaut, R., 2008, The Garnaut Climate Change Review: Final Report. Cambridge University Press, Port Melbourne, Australia, 680 pp, ISBN 9780521744447.
IPCC, 2001, Climate Change 2001: The Scientific Basis: Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change [Houghton, J.T., Y. Ding, D.J. Griggs, M. Noguer, P.J. van der Linden, X. Dai, K. Maskell and C.A. Johnson (eds.)]. Cambridge University Press, Cambridge, United Kingdom, and New York, NY, USA.
IPCC, 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, 2007 [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Avery, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom, and New York, NY, USA.
Myhre et al., 1998, New estimates of radiative forcing due to well mixed greenhouse gases. Geophysical Research Letters25:14, 2715–2718, doi:10.1029/98GL01908.
Ramanathan, V., R. Cicerone, H. Singh and J. Kiehl, 1985, Trace gas trends and their potential role in climate change, J. Geophys. Res.90: 5547-5566.
Solomon, S., G.-K. Plattner, and P. Friedlingstein, 2009, Irreversible climate change due to carbon dioxide emissions, PNAS 106:6, 1704-1709, doi:10.1073/pnas.0812721106.
Tans, P., 2012, Atmospheric CO2 concentrations (ppmv) at Mauna Loa, Hawaii, 1958-2008, at ftp://ftp.cmdl.noaa.gov/ccg/co2/trends/co2_annmean_mlo.txt.
Acknowledgements
The author is grateful to Dr. Patrick Michaels for having drawn his attention to the near-zero-trend in the annual CO2 emissions/concentration-growth ratios that is confirmed here.
Annex: supplementary material
Values of the climate sensitivity parameter λ
If net temperature feedbacks exceed zero, the climate sensitivity parameter λ is not constant: as longer- and longer-acting feedbacks begin to act, it will tend to increase between the time of a forcing to the time when equilibrium is restored to the climate 1000-3000 years after the forcing that perturbed it (Solomon et al., 2009). Illustrative values of λ are given below.
The sensitivity parameter derived from the present result and applicable to the 49 years 1960-2008 is 0.27 K W–1 m2.
Where temperature feedbacks sum to zero, the instantaneous value λ0 is 0.31 K W–1 m2 (derived from IPCC (2007, p. 631 fn.: see also Soden & Held, 2006).
Garnaut (2008) talks of keeping greenhouse-gas rises to 450 ppmv CO2-equivalent above the 280 ppmv prevalent in 1750, so as to hold 21st-century global warming since then to 2 K, implying λ262 = 2 / [5.35 ln{(280 + 450) / 280}] = 0.39 K W–1 m2.
As explained in the text, the IPCC’s implicit climate-sensitivity parameter for the 21st century is λ100 = 1.56 / [5.35 ln(713/368)] = 0.44 K W–1 m2.
On each emissions scenario, the IPCC’s estimate of the bicentennial-scale transient-sensitivity parameter λ200 is 0.49 K W–1 m2 (derived in Table 0), a value supported by IPCC (2001, p. 354, citing Ramanathan, 1985).
The implicit value of the equilibrium-sensitivity parameter λequ is the warming currently predicted in response to a CO2 doubling, i.e. 3.26 K (IPCC, 2007, p. 798, Box 10.2), divided by the forcing of 5.35 ln 2 = 3.71 W m–2 at that doubling. Thus, λequ = 0.88 K W–1 m2.
Additional tables in the annex (which cannot reproduce properly here in blog format) are in the PDF file for this paper:
monckton_climate_sensitivity (PDF)
Richard Courtney,
From introductory calculus you may recall that if the rate of change of two variables, dy/dt and dx/dt, are proportional with a constant k, the variable themselves will related by y = k x + c, where c is the constant of integration.
If you didn’t do calculus, you should be aware that in general you need both the slope and intercept of a straight-line relationship to convert between two parameters (e.g. Celsius and Fahrenheit).
Monckton has assumed that the intercept is zero between total emissions atmospheric concentration (or alternatively omitted the constant of integration). But it isn’t – there was a little less than 300 ppm of CO2 before any emissions by humans. Hence his calculation of the temperature increase based on a single value for emissions is just wrong. Just as for concentration, a ratio of emissions is required to derive the change in temperature. Monckton’s inclusion of emissions provides absolutely no independent constraint on the climate sensitivity.
What with this basic analytical error, and an attack on Gore which rather shows him to be the one “making things up”, Monckton has not had his finest week.
richardscourtney says:
August 31, 2012 at 1:05 pm
Tom P:
I would welcome expansion/explanation of the points in your post at August 31, 2012 at 12:18 pm.
You say
I’m afraid there’s a schoolboy error by Monckton: if the rate of annual increase in CO2 concentration is proportional to the annual amount of carbon emissions, that does not mean that CO2 concentration is proportional to total emissions: a constant of integration been omitted.
and
In fact total anthropogenic emissions match very well to atmospheric CO2 concentration (http://imageshack.us/photo/my-images/703/emissionsvsconc.png/).
But if the “total anthropogenic emissions match very well to atmospheric CO2 concentration” then what is the problem?
Where is the “schoolboy error”?
What relevance is the “constant of integration”?
If dCO2/dt=k*dE/dt where E is Emissions
then CO2=k*E + C where C is the constant of integration
therefore CO2 is proportional to (E-C/k) not proportional to E
from the data CO2 is proportional to E+10^6
i.e. CO2= (E+10^6)/3855.8
NOT CO2=E/3855.8
If you just take the slope of the plot, as Monckton did, to convert from emissions to concentration and hence derive a temperature increase, you get the wrong answer.
If the calculation is done properly from this plot, the warming predicted from anthropogenic emissions is precisely the same as that predicted from concentration: Monckton’s analysis produces no independent constraint at all!
Quite so as shown above
“If the facts are against you, pound on the law. If the law is against you, pound on the facts.”
Sounds like a witty adage – except for it isn’t. The law simply assesses the facts, well, in light of what the law actually says. It is not meaningful to pound on either one independently. Anyway, are you trying to imply that I have previously try to bring forward either the law or facts in vain?
Tom P:
re your attempt at a reply to me which you provide at August 31, 2012 at 1:59 pm.
The equation of a straight line is not calculus: it is algebra (clearly, I am less innumerate than you).
Lord Monckton did not convert between F and C.
He considered the difference between two values on a linear relationship so the intercept is not relevant for his calculation.
Cut out the BS. You claimed Lord Monckton did not do the calculation “properly”.
I asked you to show how and why it should be done “properly”.
You have not done that.
Your reference to Gore (whose pseudoscience was trashed in a UK High Court) has no relevance.
You are ‘blowing smoke’ and it does not screen your behaviour.
Richard
Greg House:
At August 31, 2012 at 1:46 pm you assert to me
Rubbish! Absolutely untrue! Complete nonsense!
Get back to me when you have gained at least a basic knowledge of what you are talking about because then we can have a rational discussion of it.
Richard
Gail Combs says:
“You are missing the whole point of the exercise. Monckton has taken the points made by IPCC and the climate scientists and showed even using their OWN points CO2 will not have the effect the IPCC states. In such a situation, using the oppositions arguments and not your own, of course you would use “weasel words””
The problem that I see is that Monckton’s stooping to use their own points gives some level of credibility to the incredible. They are wrong in so many ways that this analysis is like swatting at mosquitoes with a sledge hammer. Or perhaps picking at fly droppings on a dung pile is even a better analogy.
Phil:
Thankyou for your post at August 31, 2012 at 2:08 pm which answers a question I put to Tom P.
You say
I do not agree because Lord Monkton says in explanation of his analysis
n.b. “the trend in the ratios of annual global CO2 emissions to annual increases in atmospheric CO2 concentrations does not differ significantly from zero”
However, it is Lord Monckton’s analysis so I leave it to him to explain the point.
Thankyou for a sensible answer which is a stark contrast to that of Tom P.
Richard
: )
Richard C,
Your phrase from Monckton’s paper is the key one:
“the trend in the ratios of annual global CO2 emissions to annual increases in atmospheric CO2 concentrations does not differ significantly from zero”
which means the ratio between the rates of change of emissions and concentrations doesn’t change over time, or in algebra:
dE/dt = k dC/dt
giving
E = kC + constant
The constant is not zero, as Monckton implicitly assumes, and hence his calculation fails.
I, too, would like to hear any explanation Monckton can offer.
richardscourtney says:
August 31, 2012 at 2:29 pm:
“Rubbish! Absolutely untrue! Complete nonsense! Get back to me when you have gained at least a basic knowledge of what you are talking about because then we can have a rational discussion of it.”
=====================================================
Richard, you do realise that this is not just our private conversation, we are talking on an open forum, don’t you? You do not need to convince me in the first place, convince the thousands of readers. And even the less experienced readers know that argumentation like “get the knowledge and then we talk” indicates that the person saying that just does not like the message and has no arguments.
[can you guys – that’s both of you – begin to play nice please? I’d hate to intervene in a good rational debate. ~ac]
Once again I am grateful to Dr. Courtney for explaining to Tom P that the equation of a straight line need not be expressed in terms of calculus. In Fig. 1, I expressed the equation in the standard linear algebraic form: y = ax + c, where a (in this instance near-zero) is the slope and c is the y-intercept: namely, the point at which the line crosses the y axis (at x = 0). Since the slope is very close to zero, it ought to have come as no surprise to Tom P that the y-intercept is close to the mean value of y across the entire period of study, which is a little above 15.5 Gte CO2 of emissions per part per million by volume of CO2 concentration change.
As I had pointed out in an earlier answer, a longer period of study would have been desirable, but reliable values for both emissions and concentration changes were not available before 1960 or after 2008, the last year for which well-corrected values are available. Over the period of study, It is of course permissible to do the calculation as I did it, and, in my submission, it is not unreasonable to draw the conclusions I drew.
If Tom P would prefer to do the calculation differently, then – instead of making the schoolboy howler of insisting on the use of calculus (and an incorrect use at that) where simple algebra suffices – he should redo the calculation to demonstrate, as rigorously and as transparently as I did, what he thinks the answers should have been, so that Dr. Courtney and I can examine his calculations and I can decide whether or to what extent I should modify my result. That is how a genuine “seeker after truth” – Al-Haytham’s beautiful phrase for the scientist – would conduct his end of the discussion.
However, I am afraid, from the sneering tone of the anonymous Tom P’s contributions, that it is not clear he is a genuine seeker after truth. Instead, he appears to be making a maladroit attempt at misdirection, introducing irrelevant considerations as though they mattered. That is the ancient logical fallacy of ignoratio elenchi – the fundamental fallacy of ignorance of the appropriate manner of conducting an enquiry: for, in the Aristotelian canon, a discussion of this kind is an enquiry intended to elucidate the truth, not a mere assertion of a priori opinions hedged about with fallacies.
Tom P then perpetrates a second and still more jarring instance of ignoratio elenchi by introducing to this straightforwardly mathematical enquiry a howling irrelevance in the shape of a half-baked discussion of a statement I had made about Al Gore’s misleading assertion that a paper on polar bears (Monnett & Gleason, 2006) had said the bears (all four of them, though Gore somehow did not mention that) had died because they had swum 60 miles to find ice in the Beaufort Sea. I correctly pointed out, in that part of the clip that Tom P carefully failed to cite, that the paper had stated the bears had been swamped by high winds and waves in a storm. Indeed, the passage that Tom P. cites from the paper explicitly states that the bears in question did not die because they had to swim long distances. The map that accompanies the Monnett & Gleason paper makes it plain that three of the four bears were in fact very close to the shore and would not have had to swim 60 miles in any event. A subsequent paper has established that polar bears are capable of swimming distances considerably in excess of 60 miles without difficulty. And, to cap it all, as I pointed out in another part of the clip that Tom P. decided to censor, the extent of sea ice in the Beaufort Sea, where the four bears died in the storm, had not declined at all in the dozen years preceding the making of Gore’s mawkish, sci-fi comedy-horror movie. Every aspect of Gore’s story was, as I said it was, fiction. Monnett & Gleason – in a passage for which they were later criticized and investigated – suggested that one day polar bears might drown if there was not enough ice (this type of unsubstantiated, speculative clause-de-style has become depressingly common among those who want to get their papers past editors who reject skeptical papers a priori), but the authors had explicitly stated that the bears Gore said had drowned swimming 60 miles to find the ice had in fact been swamped by high winds and high seas in an Arctic storm – an event not dissimilar to the recent storm that has greatly reduced the extent of sea ice as the summer minimum approaches.
I see that another cravenly anonymous contributor, “Matt”, has resorted to a snide ad-hominem remark about whether I am regarded as notable in Britain (well, der Prophet gilt nichts im Vaterland). Matt’s remark, too, is an irrelevance, and is a further instance of ignoratio elenchi. I am not sure why the moderators allowed it. It is worth pointing out that the chief reason why the climate extremists have so comprehensively lost the scientific argument is that they resort with such unbecoming frequency to egregious logical fallacies which, in any previous generation, would have been laughed at. It must surely have become apparent to “Matt” that his childish interposition of ad-hominem irrelevancies into a serious scientific discussion is unlikely to commend his or her argument (if there is one) to the readers of this column.
Finally, Mr. House makes the common error of assuming – or at any rate stating – that greenhouse warming and negative temperature feedback are incompatible. Not so: in the absence of feedbacks, as explained in the annex, the climate-sensitivity parameter (in the IPCC’s understanding) is 0.31 Kelvin per Watt per square meter, from which it follows that a somewhat negative feedback, giving a parameter of, say, 0.27, would still cause 1 K (2 F) warming at equilibrium in response to a doubling of atmospheric CO2 concentration. Furthermore, because the curve of climate sensitivity against the feedback closed-loop gain gamma exhibits a near-zero slope over the negative-feedback interval gamma on [0, 1], even at a zero loop gain – implying strongly negative feedbacks – almost 0.5 K of CO2-driven warming would be expected.
On a similar point, Chris Y makes a common error that I myself once made: he assumes that the climate-sensitivity parameter is determined from surface temperature and radiative flux. In fact, it is conventionally determined by reference to incoming radiation at the characteristic-emission altitude, about 5 miles up in the mid-troposphere. That altitude varies inversely with latitude, but it is defined as the altitude at which incoming and outgoing radiative fluxes balance. The incoming flux is known by direct measurement via satellite to be 1362 W/m2, which must be divided by 4 to allow for the ratio of the surface area of a disk to a sphere, and must also be reduced to allow for the Earth’s reflectance or albedo, giving about 238 Watts per square meter. From the Stefan-Boltzmann equation, the emission temperature (assuming emissivity is unity, from which assumption no great error arises) is 254 K; and a little simple differential calculus tells us that, to a first approximation, the instantaneous or Planck sensitivity parameter (the first differential of the equation) is 254 / (4 * 238) = 0.267 K/W/m2. However, to allow for the non-uniform latitudinal distribution of mean temperatures in the mid-troposphere, this value should be increased by approximately one-sixth to the IPCC’s 0.31 K/W/m2. I have verified this value using 30 years of satellite temperature-anomaly data for the mid-troposphere at all latitudes, kindly supplied by Dr. John Christy of the University of Alabama at Huntsville. Some authorities say that the radiation should be taken at the characteristic-emission level and the temperature taken at the Earth’s surface: if so, according to my model, on surface data supplied by Dr. Christy, the value of the instantaneous sensitivity parameter rises to 0.33 K/W/m2.
I am genuinely interested, as always, in considering serious scientific arguments that either underline or undermine my analysis. Either way, science advances. Warmest thanks to everyone for their interest, and to the patient and diligent moderators for facilitating a high standard of discussion.
rgbatduke says:
August 31, 2012 at 1:20 pm
Any chance of funding from Duke for another try?
Chuckle. But you know that. My entire participation (such as it is) in Global Climate or Climate Change or whatever one would like to call it is an utterly unfunded, unproductive hobby…
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Sleepalot provided this graph I do not know if the data collected would be of use.
home page? http://www.shadowchaser.demon.co.uk/eclipse/
Matt says:
August 31, 2012 at 2:10 pm
“If the facts are against you, pound on the law. If the law is against you, pound on the facts….
_____________________
Matt, google the line, it is an old lawyer joke.
Jim G says:
August 31, 2012 at 2:38 pm
The problem that I see is that Monckton’s stooping to use their own points gives some level of credibility to the incredible. ….
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To us maybe but we are not his real audience it is the fence sitters and wobblers.
as Monckton said
And he is correct.
The biggest weakness in the IPCC’s whole argument is the positive feed of water vapour back multiplying the effect of an increase in CO2 by a factor of three to four.
The data shows it is wrong. NOAA graph of Atmospheric Specific Humidity. for 1948 to present. The change ~ 1994/1995 is interesting since HenryP states that is when his data shows the start of a period of cooling
Christopher Monckton claims, “the IPCC’s implicit climate-sensitivity parameter for the 21st century is 1.56 / [5.35 ln(713/368)], or 0.44 K /W–1 m2.” [ie 0.44K per W/m^2].
That is wrong.
The temperature difference, 1.56K, used in that expression includes the necessary recognition of the lack of equilibrium (between average global temperature and atmospheric CO2) in 2000 with CO2 at 368ppmv (hence the expression “0.6 K is stated to be in the pipeline” used by Monckton), but there is no such recognition of a similar lack of equilibrium for the condition in 2100 with CO2 at 713ppmv, where a similar “in the pipeline” discrepancy due to lack of equilibrium will also exist and also needs to be taken into account.
The “in the pipeline” further increase in temperature that will similarly exist in 2100 due to this disequilibrium is likely to be greater than the 0.6K used by Monckton for 2000, since the ratio of CO2 concentrations between 2100 and 2000, (ie 713/368 = 1.9375) used in the calculation is greater than that between 1900 and 2000, (ie 368/296 = 1.243), 296ppmv being the CO2 concentration in 1900. Those latter figures can only give a rough indication, but what they show is atmospheric CO2 rising proportionally more rapidly in the 21st century than in the 20th, hence a greater “in the pipeline” figure is to be expected.
If the “in the pipeline” discrepancy in 2100 used in the calculation were 1.1K, (rather than being omitted altogether by Monckton), then the climate sensitivity would be 0.75K per W/M^2, in line with the IPCC , [since (1.56+1.1)/[5.35 ln(713/368)] = 0.75]
chris y you write “I assume a blackbody radiator as the starting point. P = 5.67E-8 * T^4. Increasing T from 288 to 289 K requires about 5.5 W/m^2 of additional incoming intensity. That gives about 0.2 C per W/m^2 for sensitivity. At warmer temperatures it is lower, cooler temperatures it is higher.”
This estimation assumes that the “structure of the atmosphere does not change”.. That is the lapse rate does not change. The lapse rate is not a feedback; it is an alternate way in which the radiation balance can be restored. So the no-feedback climate sensitivity that you have estimated is not correct. I have tried to find someone to try this argument out on. Are you prepared to discuss it with me?
He has assumed that the ratio of 0.7 that was derived for 1900-2100 applies to the period up till now. If you look more closely at the IPCC numbers, the ratio till present is nearer 1.0 because aerosol effects have mostly canceled the non-CO2 warming effects, leaving the effect as equivalent to CO2 alone. This cancellation is easily seen from the IPCC forcings to date. Later the aerosol growth is not expected to be so fast because of its limited lifetime in the atmosphere, so the forcing change starts to be dominated by the accumulating GHGs of which CO2 may be more than half.
Monckton of Brenchley says:
August 31, 2012 at 3:55 pm:
“Finally, Mr. House makes the common error of assuming – or at any rate stating – that greenhouse warming and negative temperature feedback are incompatible. Not so: in the absence of feedbacks, as explained in the annex, the climate-sensitivity parameter (in the IPCC’s understanding) is 0.31 Kelvin per Watt per square meter, from which it follows that a somewhat negative feedback, giving a parameter of, say, 0.27, would still cause 1 K (2 F) warming at equilibrium in response to a doubling of atmospheric CO2 concentration.”
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Christopher, “a somewhat negative feedback…would still cause…warming”, right, no problem with that, but only if this negative feedback were possible.
Now, assuming that a negative feedback is possible does not refute my point that a negative feedback is impossible. It is a pure matter of logic. It essentially goes like that: – GH: “A negative feedback is impossible, because…” – MoB: “I assume a negative feedback is possible”.
I am sorry, but your assumption-argument misses the point. It is OK if you possibly test something on this blog, but the notion about a “negative feedback” is not good.
And as a by-product of this little constructive debate we can see that the strategy “there is greenhouse gases warming but there are no positive feedbacks” is not good. I can go deeper into details, if you like.
Monckton of Brenchley says:
August 31, 2012 at 7:59 am
“Henry Clark says that there was only 0.3 K warming from the 1930s to the present, so I ought not to have calculated that there was 0.4 K warming in the 49 year 1960-2008. However, I have merely followed the data. The least-squares linear-regression trend on the HadCRUt3 data over the period is 0.66 K”
HADCRUT3 is fudged data. CRU “data” (and the other dataset also adjusted by CAGW movement proponents: GISS) does not match reality seen outside of politically correct historical revisionism. See, for example:
http://www.real-science.com/hansens-tremendous-data-tampering
http://hidethedecline.eu/pages/posts/part1-the-perplexing-temperature-data-published-1974-84-and-recent-temperature-data-181.php
and the rest in the series
For a simple illustration of the standard tactic, these guys were sloppy enough to leave an electronic trail where, for instance, http://www.giss.nasa.gov/research/briefs/hansen_07/fig1x.gif shows the 5-year mean of U.S. temperature in the high point of the 1980s was 0.4 degrees Celsius cooler than such in the 1930s, but, in utter contradiction, later they realized next to nobody pays enough attention to quantitatively reading graphs so they could get away with the fudging in http://data.giss.nasa.gov/gistemp/graphs_v3/Fig.D.gif making the same less than 0.1 degrees Celsius apart instead.
Hansen (GISS) is an extremist activist protester repeatedly arrested. His ally of Mann has outright stated his admiration of Ehrlich. And CRU (source of HADCRUT) is infamous for climategate.
The method used by GISS and CRU is the standard way: In the words of http://www.historiography-project.org/misc/biglie.html in another context, repeat something “so often that virtually no one bothers to challenge it.”
Yet all one has to do to for such to break down is go outside where enviro-activists are dominant, a locale bounded in time and in space: As illustrated in my last comment, pre-1980s sources countradict the revisionism and so do later ones from authors in Russia (plus some within the Anglosphere but with honest objective individuals less inclined to try entering the field at this point).
You already know untrue claims are common but may not want to try to delve into multiple matters at once. However, this is one of those most important, and even skeptics too often fall into implicitly treating untrue but highly publicized revisionism as if accurate, without a word of question.
I read Tamino, and I understand. I read Monckton, and I’m baffled.
That doesn’t mean Monckton is wrong, but it does mean that Tamino is a better communicator.
Though having repeatedly been warned against the folly of it, Lord Monckton continues to claim that there is, in nature, the constant that he and others call “the climate sensitivity” (aka “the equilibrium climate sensitivity.”) The climate sensitivity is the proportionality constant in a purported linear mapping from increases in the logarithm of the CO2 concentration to increases in the spatially averaged equilibrium surface air temperature at Earth’s surface. As the equilibrium temperature is non-observable, the conjecture that there is in nature this mapping will forever remain untestable and thus unscientific.
In my previous post, please strike “surface air temperature” and replace this phrase by “air temperature.”
Some further replies to correspondents on scientific questions.
“Slioch” says that if I had added the IPCC’s 0.6 K warming in the pipeline at 2000 to the CO2-driven of 1.56 K 21st-century CO2-driven warming that is the IPCC’s implicit central estimate I should have derived a centennial-scale climate sensitivity parameter of 0,75 rather than 0.44 Kelvin per Watt per square meter. It was precisely to forestall errors such as Slioch’s that I provided, in the Annex, a list of various values for the climate-sensitivity parameter, including the equilibrium value, which, at 0.88 K/W/m2, is scarcely greater than that chosen by Slioch as his favored centennial parameter. He says this is “in line with IPCC”, but does not state any precise, quantitatie reference for his assertion. His approach would imply that very nearly all temperature feedbacks had already acted, and that is contrary to the literature – the lead author of the IPCC’s 2007 report, in a paper published in 2009, said that equilibrium would not be reached for 1000-3000 years. Furthermore, he has mixed apples with pears – delicious, but inappropriate. My determination of the IPCC’s implicit centennial value 0.44 K/W/m2 for the 21st-century climate sensitivity parameter was derived from CO2 forcings alone, but the IPCC’s 0.6 K warming in the pipeline is, of course, from all anthropogenic sources. Slioch has also double-counted the warming in the pipeline, putting both the 0.6 K pre-2000 pipeline warming and his assumed 0.5 K 21st-century 21st-century pipeline warming into the 21st century. Also, from the fact that the IPCC’s implicit estimates of centennial warming and bicentennial warming are 0.44 and 0.5 K respectively, one should deduce that the absurdly rapid growth in the climate-sensitivity parameter from the instantaneous or unperturbed 0,31 to his suggested 0.75 K/”/m2 in little more than a century is implausible, to say the least. Besides, if my reasoning in the present paper is correct, the true climate-sensitivity parameter for 1960-2008 is 0.27 K/W/m2, there would be cooling, not warming, in the pipeline at 2000, and the paper does state explicitly that if the key result is correct there was no in-the-pipeline warming at 2000. The best way to get a feel for the IPCC’s various values of the climate-sensitivity parameter over time is to have a look at the values I have derived and listed in the Annex. The IPCC’s assumption that half of the warming that it wishes should have arisen as a result of our sins of emission before 2000 has not arisen is based on its assumption that the centennial-scale sensitivity parameter, at 0.44 K/W/m2, is half of its assumed equilibrium parameter, which is 0.88 K/W/m2. But, since equilibrium will not occur for 1000-3000 years, as noted above, even if it were appropriate for the IPCC to assume that 0.6 K of warming was already in the pipeline it would certainly not be appropriate to put more than half of that into the 21st-century calculation.
“Jim D” says I have “assumed” that the IPCC’s implicit fraction of total anthropogenic warming contributed by CO2 is 0.7. I have not “assumed” it: I have determined it by calculation. See Table 0 in the Annex. It is exasperating that the IPCC makes so few of these essential quantities explicit – it is almost as though they were doing their very best to prevent anyone from checking their methods and results. However, in the 2001 report they do state that the CO2 fraction is approximately the value I have had to calculate from Table SPM.3 and Figure 10.26 of the 2007 report, to ensure that they currently adhere to their 2001 value, which of course takes into account the effect of negative anthropogenic forcings such as particulate aerosols (which the IPCC cannot measure and has, therefore, adopted as a convenient fudge-factor allowing it to pretend that climate sensitivity is a great deal higher than it is).
Mr. House, having realized that he had been incorrect in assuming that net-negative feedbacks and global warming could not co-exist, shifts his ground in a tiresomely characteristic fashion and tries to maintain that there is no such thing as a negative feedback in the first place. I have much sympathy with Dr. Courtney’s trenchant and apposite remark to the effect that Mr. House ought to go away and learn at least the basics of climate sensitivity theory before he makes stuff like this up. Mr. House might usefully begin his reading with Bode’s 1945 book on feedback amplification in electronic circuits – for it is from process engineering that the feedback methodology now used by climatologists is derived. He may also like to read Hansen (1984), which, though full of elementary mistakes that ought not to have passed peer review, does give quite a clear account of how feedback amplification is thought to apply to the climate. There is also a splendid pedagogical paper by Professor Lindzen’s former student Gerard Roe (2009), which gives a fascinating account of the moment at which the concept of negative feedbacks was discovered, and goes on to give an excellent, lucid explanation of how feedback theory is applied to the climate. Dr. Courtney is right: Mr. House would do well not to try to intervene further in discussions at this scientific level until he has familiarized himself at least with the basic literature. From my own examination of this question, I conclude either that the feedback model, though certainly appropriate to electronic circuitry, may not be appropriate when considering the climate, or that climate feedbacks must be either net-negative or, at worst, barely positive rather than, as the IPCC assumes, very strongly positive. A homeostatic model seems more appropriate than a feedback model, given the nature of the atmosphere’s upper and lower boundaries and the remarkable near-invariance of surface temperatures over the past 64 million years. Finally on this point, I must apologize for an error in my earlier answer to Mr. House. I had stated that the relevant interval of loop gains covering negative feedbacks was [0, 1], when I had of course intended to write [-1, 0).
Henry Clark rightly points out that the HadCRUt3 temperature record, like so many of them, has been tampered with to steepen the apparent slope of warming over the 20th century. However, rather than trying to substitute my own judgment for that of the soi-disant experts, I have preferred simply to accept their data as is (sed solum ad argumentum), because, even if one accepts it as is, the conclusions that the usual suspects attempt to draw from it are manifestly inappropriate. By accepting their premises for the sake of argument, I remove a big bone of contention from the discussion and force them to examine the inconsistencies between their premises and the inappropriate conclusion of high climate sensitivity that they draw from them.
Mr. Brooks says he can understand “Tamino” (whoever that may be) but is baffled by me. I do regret that in my attempt to be very brief I have not been as clear as I usually try to be, and one or two of the scientists who have kindly read my argument have made the same criticism. Others, on the other hand, have found the paper clear: but they are climatologists and are familiar with the actually rather elementary concepts that I am discussing here.
Mr. Oldberg says I ought not to mention equilibrium climate sensitivity because it will not occur for thousands of years and – as a hypothesis – is not testable today. I mentioned equilibrium climate sensitivity only in passing, to assist readers in grasping the appropriateness (or inappropriateness) of the IPCC’s shorter-term climate-sensitivity parameters. And it was the shorter-term parameters that I used as the benchmark for my calculations. These parameters are testable, and the present paper provides one method of testing them. In any event, Mr. Oldberg should learn to apply logical techniques with due care; merely because a quantity cannot yet be determined, one should not – as he does – go on to argue that the phenomenon that the quantity is intended to measure does not exist. If he really wants to persist in arguing that there is no such thing as equilibrium climate sensitivity, he should take the matter up with the IPCC, not with me. Since they use it, and provide an implicit value for it, i am entitled to provide evidence that their value is greatly overstated.
Lord Monckton:
Thank you for taking the time to reply. As a concept, the “climate sensitivity” (CS) has the shortcoming of being defined on an equilibrium temperature. This temperature is not an example of an observable.. As we cannot observe it, when the IPCC, you or anyone else claims a numerical value for the CS, this claim is insusceptible to being refuted. As it is insusceptible to being refuted, this claim is not “scientific.”
The central flaw in the IPCC’s argument for CAGW is not that the IPCC assigns too high of a numerical value to the CS but rather that the CS is not a scientific concept. In representing that its conclusion is a consequence of a scientific inquiry, the IPCC has lied. .
His Lordship persists in his errors. He continues to insist that his analysis of climate sensitivity via emissions per increase in CO2 concentration is useful. It is not.
His analysis finds the mean emissions/concentration-growth ratio, which is equal to the sum of emissions/sum concentration-growth. He total emissions by this number. The result is of course the total emissions.
For those that prefer this algebraically
sum(emissions)
___________________________________
sum(emissions) / sum(concentration-growth) = sum(concentration-growth)
Estimating sensitivity via emissions is detour. it serves no purpose except to confound the gullible. It would be as useful, and easy, to include the price of lemons in the analysis.
His second error is to presume that because he declares that “If feedbacks operating over the short to medium term are indeed net-negative, there is no warming in the pipeline from past emissions” there is not warming in the pipeline. First, supposing feedbacks to be net-negative does not make them so. Second, feedbacks are not the only issue relevant to warming in the pipeline. The other is thermal inertia. As there are element of the climate system, such as the ocean, that have considerable thermal inertia, there will be delayed warming whatever the feedback.
Errare humanum est perseverare diabolicum.
Monckton of Brenchley says:
September 1, 2012 at 12:40 am
“Henry Clark rightly points out that the HadCRUt3 temperature record, like so many of them, has been tampered with to steepen the apparent slope of warming over the 20th century. However, rather than trying to substitute my own judgment for that of the soi-disant experts, I have preferred simply to accept their data as is (sed solum ad argumentum), because, even if one accepts it as is, the conclusions that the usual suspects attempt to draw from it are manifestly inappropriate. By accepting their premises for the sake of argument, I remove a big bone of contention from the discussion and force them to examine the inconsistencies between their premises and the inappropriate conclusion of high climate sensitivity that they draw from them.”
Fair enough. Most of all, I just wanted to make sure you were fully aware,* as I know you are one of the more major public figures on the skeptic side. Thank you for the reply.
Although I think presentation of CRU data could best come with a brief note about how the reader should not assume it is accurate, I understand the practicality of focusing on one (other) topic at a time sometimes.
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* Really there needs to be an equally convenient online dataset of tabular values (as well as graphs) for global average temperature all the way back to the 19th century for sources unlikely to be biased, not just NH or SH data alone having to be manually combined, since often another factor in even skeptics predominately using CRU/GISS-source data is that others are less convenient. For instance, even woodfortrees.org does not have such now. Perhaps I’ll try to create such myself sometime, using graph-to-data digitizing software if necessary.