By Christopher Monckton of Brenchley
My commentary written for Remote Sensing on the empirical determination of climate sensitivity, published by the splendid Anthony Watts some days ago, has aroused a great deal of interest among his multitudes of readers. It is circulating among climate scientists on both sides of the debate. Several of Anthony’s readers have taken the trouble to make some helpful comments. Since some of these are buried among the usual debates between trolls on how awful I am, and others were kindly communicated privately, I have asked Anthony to allow me, first and foremost, to thank those readers who have been constructive with their comments, and to allow his readers the chance to share the comments I have received.
Joel Shore pointed out that Schwartz, whose paper of 2007 I had cited as finding climate sensitivity to be ~1 K, wrote a second paper in 2008 finding it close to 2 K. Shore assumed I had seen but suppressed the second paper. By now, most of Anthony’s readers will perhaps think less ungenerously of me than that. The new .pdf version of the commentary, available from Anthony’s website (here), omits both Schwartz papers: but they will be included in a fuller version of the argument in due course, along with other papers which use observation and measurement, rather than mere modeling, to determine climate sensitivity.
Professor Michael Asten of Monash University helpfully provided a proper reference in the reviewed literature for Christopher Scotese’s 1999 paper reconstructing mean global surface temperatures from the Cambrian Era to the present. This, too, has been incorporated into the new .pdf.
Professor Asten also supplied a copy of a paper by David Douglass and John Christy, published in that vital outlet for truth Energy & Environment in 2009, and concluding on the basis of recent temperature trends that feedbacks were not likely to be net-positive, implying climate sensitivity ~1 K. I shall certainly be including that paper and several others in the final version of the full-length paper that underlies the commentary published by Anthony. This paper is now in draft and I should be happy to send it to any interested reader who emails monckton@mail.com.
A regular critic, Lucia Liljegren was, as all too often before, eager to attack my calculations – she erred in publishing a denial that I sent her a reference that I can prove she received; and not factually accurate in blogging that “Monckton’s” Planck parameter was “pulled out of a hat” when I had shown her that in my commentary I had accepted the IPCC’s value as correct. She was misleading her readers in not telling them that the “out-of-a-hat” relationship she complains of is one which Kiehl and Trenberth (1997) had assumed, with a small variation (their implicit λ0 is 0.18 rather than the 0.15 I derived from their paper via Kimoto, 2009); and selective in not passing on that I had told her they were wrong to assume that a blackbody relationship between flux and temperature holds at the surface (if it did, as my commentary said, it would imply a climate sensitivity ~1 K).
A troll (commenter on WUWT) said I had “fabricated” the forcing function for CO2. When I pointed out that I had obtained it from Myhre et al. (1998), cited with approval in IPCC (2001, 2007), he whined at being called a troll (so don’t accuse me of “fabricating” stuff, then, particularly when I have taken care to cite multiple sources, none of which you were able to challenge) and dug himself further in by alleging that the IPCC had also “fabricated” the CO2 forcing function. No: the IPCC got it from Myhre et al., who in turn derived it by inter-comparison between three models. I didn’t and don’t warrant that the CO2 forcing function is right: that is above my pay-grade. However, Chris Essex, the lively mathematician who did some of the earliest spectral-line modeling of the CO2 forcing effect, confirms that Myhre and the IPCC are right to state that the function is a logarithmic one. Therefore, until I have evidence that it is wrong, I shall continue to use it in my calculations.
Another troll said – as usual, without providing any evidence – that I had mis-stated the result from process engineering that provides a decisive (and low) upper bound to climate sensitivity. In fact, the result came from a process engineer, Dr. David Evans, who is one of the finest intuitive mathematicians I have met. He spent much of his early career designing and building electrical circuitry and cannot, therefore, fairly be accused of not knowing what he is talking about. Since the resulting fundamental upper limit to climate sensitivity is as low as 1.2 K, I thought readers might be interested to have a fuller account of it, which is very substantially the work of David Evans. It is posted below this note.
Hereward Corley pointed out that the reference to Shaviv (2008) should have been Shaviv (2005). Nir Shaviv – another genius of a mathematician – had originally sent me the paper saying it was from 2008, but the version he sent was an undated pre-publication copy. Mr. Corley also kindly supplied half a dozen further papers that determine climate sensitivity empirically. Most of the papers find it low, and all find it below the IPCC’s estimates. The papers are Chylek & Lohman (2008); Douglass & Knox (2005); Gregory et al. (2002); Hoffert & Covey (1992); Idso (1998); and Loehle & Scafetta (2011).
I should be most grateful if readers would be kind enough to draw my attention to any further papers that determine climate sensitivity by empirical methods rather than by the use of general-circulation models. I don’t mind what answers the papers come to, but I only want those that attempted to reach the answer by measurement, observation, and the application of established theory to the results.
Many thanks again to all of you for your interest and assistance. Too many of the peer-reviewed journals are no longer professional enough or unprejudiced enough to publish anything that questions the new State religion of supposedly catastrophic manmade global warming. Remote Sensing, for instance has still not had the courtesy to acknowledge the commentary I sent. Since the editors of the learned journals seem to have abdicated their role as impartial philosopher-kings, WattsUpWithThat is now the place where (in between the whining and whiffling and waffling of the trolls) true science is done.
The fundamental constraint on climate sensitivity
A fundamental constraint rules out strongly net-positive temperature feedbacks acting to amplify warming triggered by emissions of greenhouse gases, with the startling result that climate sensitivity cannot much exceed 1.2 K.
Sensitivity to doubled CO2 concentration is the product of three parameters (Eq. 1):
- the radiative forcing ΔF2x = 5.35 ln 2 = 3.708 W m–2 at CO2 doubling (Eq. 2), from the function in Myhre et al. (1998) and IPCC (2001, 2007);
- the Planck zero-feedback climate sensitivity parameter λ0 = 0.3125 K W–1 m2 (Eq. 3), equivalent to the first differential of the fundamental equation of radiative transfer in terms of mean emission temperature TE and the corresponding flux FE at the characteristic-emission altitude (CEA, one optical depth down into the atmosphere, where incoming and outgoing fluxes are identical), augmented by approximately one-sixth to allow for latitudinal variation (IPCC, 2007, p. 631 fn.);
- the overall feedback gain factor G (Eq. 4), equivalent, where feedbacks are assumed linear as here, to (1 – g)–1, where the feedback loop gain g is the product of λ0 and the sum f of all unamplified temperature feedbacks f1, f2, … fn, such that the final or post-feedback climate sensitivity parameter λ is the product of λ0 and G.
The values of the first two of the three parameters whose product is climate sensitivity are known (Eqs. 2-3). The general-circulation models, following pioneering authors such as Hansen (1984), assume that the feedbacks acting upon the climate object are strongly net-positive (G 1: the IPCC’s implicit central estimate is G = 2.81). In practice, however, neither individual temperature feedbacks nor their sum can be directly measured; nor can feedbacks be readily distinguished from forcings (Spencer & Braswell, 2010, 2011; but see Dessler, 2010, 2011).
Temperature feedbacks – in effect, forcings that occur because a temperature change has triggered them – are the greatest of the many uncertainties that complicate the determination of climate sensitivity. The methodology that the models adopt was first considered in detail by Bode (1945) and is encapsulated at its simplest, assuming all feedbacks are linear, in Eq. (4). Models attempt to determine the value of each distinct positive (temperature-amplifying) and negative (temperature-attenuating) feedback in Watts per square meter per Kelvin of original warming. The feedbacks f1, f2, … fn are then summed and mutually amplified (Eq. 4).
Fig. 1 schematizes the feedback loop:
Figure 1. A forcing ΔF is input (top left) by multiplication to the final sensitivity parameter λ = λ0G, where g = λ0f = 0.645 is the IPCC’s implicit central estimate of the loop gain and G = (1 – g)–1 = 2.813 [not shown] is the overall gain factor: i.e., the factor by which the temperature change T0 = ΔF λ0 triggered by the original forcing is multiplied to yield the output final climate sensitivity ΔT = ΔF λ = ΔF λ0 G (top right). To generate λ = λ0 G, the feedbacks f1, f2, … fn, summing to f, are mutually amplified via Eq. (4). Stated values of λ0, f, g, G, and λare those implicit in the IPCC’s central estimate ΔT2x = 3.26 K (2007, p. 798, Box 10.2) in response to ΔF2x = 5.35 ln 2 = 3.708 W m–2. Values for individual feedbacks f1–f4 are taken from Soden & Held (2006). (Author’s diagram from a drawing by Dr. David Evans).
The modelers’ attempts to identify and aggregate individual temperature feedbacks, while understandable, do not overcome the difficulties in distinguishing feedbacks from forcings or even from each other, or in determining the effect of overlaps between them. The methodology’s chief drawback, however, is that in concentrating on individual rather than aggregate feedbacks it overlooks a fundamental physical constraint on the magnitude of the feedback loop gain g in Eq. (4).
Paleoclimate studies indicate that in the past billion years the Earth’s absolute global mean surface temperature has not varied by more than 3% (~8 K) either side of the 750-million-year mean (Fig. 2):
Figure 2. Global mean surface temperature over the past 750 million years, reconstructed by Scotese (1999), showing variations not exceeding 8 K (<3%) either side of the 291 K (18 °C) mean.
Consistent with Scotese’s result, Zachos et al. (2001), reviewing detailed evidence from deep-sea sediment cores, concluded that in the past 65 Ma the greatest departure from the long-run mean was an increase of 8 K at the Poles, and less elsewhere, during the late Paleocene thermal maximum 55 Ma BP.
While even a 3% variation either side of the long-run mean causes ice ages at one era and hothouse conditions at another, in absolute terms the temperature homeostasis of the climate object is formidable. At no point in the geologically recent history of the planet has a runaway warming occurred. The Earth’s temperature stability raises the question what is the maximum feedback loop gain consistent with the long-term maintenance of stability in an object upon which feedbacks operate.
The IPCC’s method of determining temperature feedbacks is explicitly founded on the feedback-amplification equation (Eq. 4, and see Hansen, 1984) discussed by Bode (1945) in connection with the prevention of feedback-induced failure in electronic circuits. A discussion of the methods adopted by process engineers to ensure that feedbacks are prevented in electronic circuits will, therefore, be relevant to a discussion of the role of feedbacks acting upon the climate object.
In the construction of electronic circuits, where one of the best-known instances of runaway feedback is the howling shriek when a microphone is placed too close to the loudspeaker to which it is connected, electronic engineers take considerable care to avoid positive feedback altogether, unless they wish to induce a deliberate instability or oscillation by compelling the loop gain to exceed unity, the singularity in Eq. (4), at which point the magnitude of the loop gain becomes undefined.
In electronic circuits for consumer goods, the values of components typically vary by up to 10% from specification owing to the vagaries of raw materials, manufacture, and assembly. Values may vary further over their lifetime from age and deterioration. Therefore engineers ensure long-term stability by designing in a negative feedback to ensure that vital circuit parameters stay close to the desired values.
Negative feedbacks were first posited by Harold S. Black in 1927 in New York, when he was looking for a way to cancel distortion in telephone relays. Roe (2009) writes:
“He describes a sudden flash of inspiration while on his commute into Manhattan on the Lackawanna Ferry. The original copy of the page of the New York Times on which he scribbled down the details of his brainwave a few days later still has pride of place at the Bell Labs Museum, where it is regarded with great reverence.”
One circuit parameter of great importance is the (closed) feedback loop gain inside any amplifier, which must be held at less than unity under all circumstances to avoid runaway positive feedback (g ≥ 1). The loop gain typically depends on the values of at least half a dozen components, and the actual value of each component may randomly vary. To ensure stability the design value of the feedback loop gain must be held one or two orders of magnitude below unity: g <0.1, or preferably <0.01.
Now consider the common view of the climate system as an engine for converting forcings to temperature changes – an object on which feedbacks act as in Fig. 1. The values of the parameters that determine the (closed) loop gain, as in an electronic circuit, are subject to vagaries. As the Earth evolves, continents drift, sometimes occupying polar or tropical positions, sometimes allowing important ocean currents to pass and sometimes impeding or diverting them; vegetation comes and goes, altering the reflective, radiative, and evaporative characteristics of the land and the properties of the coupled atmosphere-ocean interface; volcanoes occasionally fill the atmosphere with smoke, sulfur, or CO2; asteroids strike; orbital characteristics change slowly but radically in accordance with the Milankovich cycles; and atmospheric concentrations of the greenhouse species, vary greatly.
In the Neoproterozoic, 750 Ma BP, CO2 concentration (today <0.04%) was ~30%: otherwise the ocean’s magnesium ions could not have united with the abundance of calcium ions and with CO2 itself to precipitate the dolomitic rocks laid down in that era. Yet mile-high glaciers came and went twice at sea level at the equator.
As in the electronic circuit, so in the climate object, the values of numerous key components contributing to the loop gain change radically over time. Yet for at least 2 Ga the Earth appears never to have endured the runaway greenhouse warming that would have occurred if the loop gain had reached unity. Therefore, the loop gain in the climate object cannot be close to unity, for otherwise random mutation of the feedback-relevant parameters of vital climate components over time would surely by now have driven it to unity. It is near-certain, therefore, that the value of the climatic feedback loop gain g today must be very much closer to 0 than to 1.
A loop gain of 0.1, then, is in practice the upper bound for very-long-term climate stability. Yet the loop gain values implicit in the IPCC’s global-warming projections of 3.26[2, 4.5] K warming in response to a CO2 doubling are well above this maximum, at 0.64[0.42, 0.74] (Eq. 8). Values such as these are far too close to the steeply-rising segment of the climate-sensitivity curve (Fig. 3) to have allowed the climate to remain temperature-stable for hundreds of millions of years, as Zachos (2001) and Scotese (1999) have reported.
Figure 3. The climate-sensitivity curve at loop gains –1.0 ≤ g < +1.0. The narrow shaded zone at bottom left indicates that climate sensitivity is stable at 0.5-1.3 K per CO2 doubling for loop gains –1.0 ≤ g ≤ +0.1, equivalent to overall feedback gain factors 0.5 ≤ G ≤ 1.1. However, climate sensitivities on the IPCC’s interval [2.0, 4.5] K (shaded zone at right) imply loop gains on the interval (+0.4, +0.8), well above the maximum loop gain that could obtain in a long-term-stable object such as the climate. At a loop gain of unity, the singularity in the feedback-amplification equation (Eq. 4), runaway feedback would occur. If the loop gain in the climate object were >0.1, then at any time conditions sufficient to push the loop gain towards unity might occur, but (see Fig. 2) have not occurred in close to a billion years (author’s figure based on diagrams in Roe, 2009; Paltridge, 2009; and Lindzen, 2011).
Fig. 3 shows the climate-sensitivity curve for loop gains g on the interval [–1, 1). It is precisely because the IPCC’s implicit interval of feedback loop gains so closely approaches unity, which is the singularity in the feedback-amplification equation (Eq. 4), that attempts to determine climate sensitivity on the basis that feedbacks are strongly net-positive can generate very high (but physically unrealistic) climate sensitivities, such as the >10 K that Murphy et al. (2009) say they cannot rule out.
If, however, the loop gain in the climate object is no greater than the theoretical maximum value g = 0.1, then, by Eq. (4), the corresponding overall feedback gain factor G is 1.11, and, by Eq. (1), climate sensitivity in response to a CO2 doubling cannot much exceed 1.2 K. No surprise, then, that the dozen or more empirical methods of deriving climate sensitivity that I included in my commentary cohered at just 1 K. If that is indeed the answer to the climate sensitivity question, it is also a mortal blow to climate extremists worldwide – but good news for everyone else.
References
Bode, H.W., 1945, Network analysis and feedback amplifier design, Van Nostrand, New York, USA, 551 pp.
Chylek, P., and U. Lohman, 2008, Aerosol radiative forcing and climate sensitivity deduced from the last glacial maximum to Holocene transition, Geophys. Res. Lett. 35, doi:10.1029/2007GL032759.
Dessler, A.E., 2010, A determination of the cloud feedback from climate variations over the past decade, Science 220, 1523-1527.
Dessler, A.E., 2011, Cloud Variations and the Earth’s Energy Budget, Geophys. Res. Lett. [in press].
Douglass, D.H., and R.S. Knox, 2005, Climate forcing by the volcanic eruption of Mount Pinatubo, Geophys. Res. Lett. 32, doi:10.1029/2004GL022119.
Douglass, D.H., and J.R. Christy, 2009, Limits on CO2 climate forcing from recent temperature data of Earth, Energy & Environment 20:1-2, 177-189.
Gregory, J.M., R.J. Stouffer, S.C. Raper, P.A. Stott, and N.A. Rayner, 2002, An observationally-based estimate of the climate sensitivity, J. Clim. 15, 3117-3121.
Hansen, J., A., Lacis, D. Rind, G. Russell, P. Stone, I. Fung, R. Ruedy, and J. Lerner, 1984, Climate sensitivity: analysis of feedback mechanisms, Meteorological Monographs 29, 130-163.
Hoffert, M.I., and C. Covey, 1992, Deriving global climate sensitivity from paloeclimate reconstructions, Nature 360, 573-576.
Idso, S.B., 1998, CO2-induced global warming: a skeptic’s view of potential climate change, Clim. Res. 10, 69-82.
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.
Kimoto, K., 2009, On the confusion of Planck feedback parameters, Energy & Environment 20:7, 1057-1066.
Lindzen, R.S., 2011, Lecture to the American Chemical Society, Aug. 28.
Loehle, C., and Scafetta, N., 2011, Climate change attribution using empirical decomposition of climatic data, Open Atmos. Sci. J. 5, 74-86.
Murphy, D. M., S. Solomon, R. W. Portmann, K. H. Rosenlof, P. M. Forster, and T. Wong 2009, An observationally-based energy balance for the Earth since 1950, J. Geophys. Res., 114, D17107, doi:10.1029/2009JD012105.
Myhre, G., E. J. Highwood, K. P. Shine, and F. Stordal, 1998, New estimates of radiative forcing due to well mixed greenhouse gases, Geophys. Res. Lett. 25:14, 2715–2718, doi:10.1029/98GL01908.
Paltridge, G., 2009, The Climate Caper, Connor Court, Sydney, Australia, 110 pp.
Roe, G., 2009, Feedbacks, Timescales, and Seeing Red, Ann. Rev. Earth. Planet. Sci. 37, 93-115.
Schwartz, S.E., 2007, Heat capacity, time constant, and sensitivity of Earth’s climate system, J. Geophys. Res. 112, D24So5, doi:10.1029/2007JD008746.
Schwartz, S.E., 2008, Reply to comments by G. Foster et al., R. Knutti et al., and N. Scafetta on “Heat Capacity, time constant, and sensitivity of Earth’s climate system”, J. Geophys. Res. 113, D15015, doi: 10.1029/2008JD009872.
Scotese, C.R., A.J. Boucot, and W.S. McKerrow, 1999, Gondwanan paleogeography and paleoclimatology, J. African Earth Sci. 28:1, 99-114.
Shaviv, N., 2005, On climate response to changes in the cosmic-ray flux and radiative budget, J. Geophys. Res., doi:10.1029.
Soden, B.J., and I.M. Held, 2006, An assessment of climate feedbacks in coupled ocean-atmosphere models. J. Clim. 19, 3354–3360.
Spencer, R.W., and W.D. Braswell, 2010, On the diagnosis of radiative feedback in the presence of unknown radiative forcing, J. Geophys. Res, 115, D16109.
Spencer, R.W., and W.D. Braswell, 2011, On the misdiagnosis of surface temperature feedbacks from variations in Earth’s radiant-energy balance, Remote Sensing 3, 1603-1613, doi:10.3390/rs3081603.
Zachos, J., M. Pagani, L. Sloan, E. Thomas, and K. Billups, 2001, Trends, Rhythms and Aberrations in Global Climate 65 Ma to Present, Science 292, 686-693.
Craig Goodrich says:
September 27, 2011 at 5:13 pm
One circuit parameter of great importance is the (closed) feedback loop gain inside any amplifier, which must be held at less than unity under all circumstances to avoid runaway positive feedback (g ≥ 1).
It took a bit to realize that what was meant here is, in electronic terms, the effect of closing the feedback loop on the amplifier, that is, the ratio of the closed loop gain to the (theoretical) open loop gain of the amp. A typical power amplifier might have a (theoretical) open loop voltage gain of 10,000 — theoretical because it would fry both itself and anything it was connected to if it were run that way —
—————————————————
Actually it wouldn’t fry itself and anything it was to which it was connected, or at least not as long as the load was larger than the minimum required for the power stage of the amplifier. A dead short on the output could do bad things depending on the amp used, but assuming you have a sufficiently large resistive load all that would happen is that the amplifier would go to one of its rails depending on the signal you were injecting and assuming you simply put a reference on the other input terminal.
I generally enjoy Monckton’s stuff but he was a bit sloppy on the electronic description. In order to assess stability you have to look at both gain and phase margin. It is perfectly acceptable to have the feedback exceed 1 and still have a stable circuit as long as the phase of the feedback does not hit 180deg at unity gain. Additionally, the way he’s formulated his equation he’s running the feedback into the positive input terminal on the amplifier which can also be done in a stable manner (tricky) but generally isn’t the way the equations are formulated. Let’s take a look at what his G term does for a couple values of g:
g=0.01 => G~=1.01: the output signal is in phase with the input signal and virtually the same magnitude.
g=1.01 => G=-100: the output signal is 100x (but stable!) and out of phase with the input.
There is no instability in either case.
And, as _Jim mentioned this gets a lot more complicated in a multi-pole, multi-zero systems with phase shift in the feedback which I am fairly certain is the case with global climate.
“”””” Roger Knights says:
September 27, 2011 at 3:57 pm
Typo(s?)? in:
“… and atmospheric concentrations of the greenhouse species, vary greatly.”
There shouldn’t be a comma, I don’t think, and “species” doesn’t sound right “””””
Fiddle faddle ! “species” is perfect to use in that situation; well unless Roger you aren’t aware that there are different species of Greenhouse Gases, such as H2O, and O3 for example; well CO2 is one also.
Well Dr Richard Lederer, the world’s foremost authority on the English language, would say you need at least a comma, any place you might have to pause for a breath in normal conversation; so I say the comma stays; since I have to pause for a breath right there at “species”.
So to re-iterate, fiddle faddle !
Doug says: September 27, 2011 at 3:35 pm Re dolomite minerals and proxies
Agreed. Years ago we introduced aspiring geos to the tern “penecontemporaneous dedolomitisation”. Are there any robust papers on this rather complex topic?
The whole discussion of focings and feedbacks belongs to the realm of climate theology. [How does a doubling of the atmospheric CO2 concentration change the number of photonics angels that may reside on a climate pin?] The fundamental error in climate modeling was made a very long time ago. This is the assumption that there is some kind of average climate equilibrium state that can be perturbed. In reality there is no such thing as climate equlilbrium. The Earth’s climate (weather) is always changing. The climate equilibrium assumption throws out the baby along with the bathwater. The piece that is missing is the Second Law of Thermodynamics. Heat transfer requres a thermal gradient or temperature difference.
The daily solar flux reaching a point on the Earth’s surface can vary from zero to about 25 MJ.m-2. How is this heat load dissipated each day through radiation, moist convection, thermal conduction and subsurface transport?
Go back and have a good look at the original assumptions made by Manabe and Wetherald in 1967. They include a blackbody surface for the Earth that has zero heat capacity [See the 2nd page].
http://www.gfdl.noaa.gov/bibliography/related_files/sm6701.pdf
The whole discussion of forcings and feedbacks and CO2 sensitivity is just computational climate astrology.
Climate change can only be understood in terms of quantitative energy transfer. The flux has to heat something with a finite heat capacity to produce a change in temperature. This requires a thermal gradient and a time dependent heat ransfer analysis.
The IPCC propaganda has been very successful in getting most people to accept the wrong assumptions and argue about the theology instead of the real science.
Let me see if i’ve got this straight, just to amplify what I see are over-riding points that Lord Monckton is making relative to the discussion of feedbacks in electronic circuits, as applicable to the climate system. I think the picture is good for concepts of feedback in general, but in fact the two systems aren’t comparable at all. As he pointed out, engineers work very hard to keep their creations operating in stable domain, where regular analytical methods apply. The climate system is nothing like this at all. The system picture of multiple feedbacks and influences is conceptually accurate, but the result is hardly linear.
I’ve years experience in control system application and theory. All linear systems are analyzed with essentially the same mathematical tools. An electronic amplifier is one instance of such a system. In these systems, correct analysis must include the frequency domain of the response, expressed using complex math (real and imaginary parts). For unconditional stability one must locate the frequency at which the phase of the otherwise negative feedback becomes positive due to inherent system time delay. It is only at this frequency (and harmonic multiples) that the feedback gain must be less than unity to enforce stability. At frequencies much lower than this critical harmonic, it is very possible to have feedback gains orders of magnitude greater than unity and still achieve stability. It is because of this fact that super-linear amplifiers exist.
The climate system is inherently different from the electronics system because it is a free body system. There are no arbitrary constraints on time domain response or feedback gain. The interactions of physical movement and energy transfer are dispersed over wide domain. The system at no time operates with stable feedbacks (in the linear system sense); rather, it always operates as a non-linear system with chaotic, fractal response. It is always unstable and never in equilibrium. It is infinitely sensitive to initial conditions. That said, the climate stays within boundaries *because* it is a chaotic, fractal system; the system follows the rules of Lorentz’s “strange attractors” which enforces the boundary conditions by that very non-linear response to non-equilibrium conditions. The system response is empirically derived to equations that appear to be analytic. Such a view is empirically correct and useful, but otherwise deceiving. In such a system, any data set correlation is evidence of first principle response, but hardly definitive.
The mathematics of chaos is hard. Electronic circuits can be analyzed on paper; the climate system cannot be analyzed on paper. The best one can do is discover empirical relations of various components of the system that happen to give rise to measurable boundary response. For sure, each mode of the system must obey the laws of physics, but the resulting interactions are so complex and the internal system gains so high, that chaos is the natural and only possible outcome. The climate system feedbacks don’t just squeal, they scream with uncertainty and noise.
To correctly generate a time domain model of processes that are inherently chaotic requires super-fine granularity and almost infinite knowledge of state, which is just another way of saying it takes more computing power and knowledge than you can possibly imagine. It’s so hard, that on first principles there is no climate model that, given certain initial conditions, is specifically accurate beyond a few days. Chaos theory doesn’t support the idea that model accuracy will exist beyond a just a few system macro-cycles if there is any uncertainty in the initial conditions. From this view, Piers Corbin’s phenomenal accuracy in long term weather predictions must be tapping into knowledge of certain fundamental forcing functions of the climate system. In effect, he is discovering the tiny influences on these sensitive initial conditions that push the climate system into various quasi-stable states. This is perfectly consistent with the essential nature of chaotic systems. And he is exactly correct that throwing more computing power at the problem won’t make it any better.
The whole climate sensitivity problem is finding the appropriate relations that give rise to specific boundary response. It may be possible that one day we will have clear understanding; it appears that we have some understanding now. But as has been pointed out here and elsewhere, pinning climate response down to any one factor is a cruel joke. Like most people here, I trust no one that pretends to know what is going on based on such a simplistic view.
-William Rostron
@ur momisugly Jim,
Maybe the greenhouse effect is as elementary as all the ‘greenhouse effect in a bottle’ experiments anyone can find on YouTube and other sources. OTOH, what is really happening?
http://myweb.cableone.net/carlallen/Site/Greenhouse%20In%20A%20Bottle-Reconsidered.html
I still want to see a published experiment that demonstrates the greenhouse effect. BTW, why is the desert warmer during the day than in the tropics at the same latitude and altitude? Maybe convection and gravity explains a lot more than meets the eye? I don’t know, being a simple man, I just ask questions because all this talk about “trapping heat”, “back radiation” and the like still doesn’t make much sense, but maybe there’s hope for me yet.
Gary Swift
I agree. But this section in Monckton’s main post discusses my blog post without engaging my technical points, but instead resorts to discussing what was communicated in the emails about these claims:
I would be happy to discuss the technical claims in my blog post which Monckton linked.
My technical claim at my blog is that the method derived in Kimoto (and relied on by Monckton) is no more likely to result in correct estimates of λ0 than merely pulling numbers out of a hat. The reason is that the derivation of their equation (18) — used by Monckton–relies on unstated physical assumptions. While implausible, some of the mathematical steps involve such highly restrictive assumptions that some assumptions must be incorrect. Consequently, the reason Kimoto’s plank parameter differs from those of others by a factor of roughly 2 likely arises from his resorting to unphysical assumptions, and consequently, Kimoto’s Plank Parameter (and Monckton’s which agrees with it.) appears to have no basis in our understanding of physics.
Unfortunately, Monckton did not engage any of the technical points in my post. He wrote a he-said/ she-said discussion of the email exchange instead.
With regard to the he-said/she-said element introduced by Monckton in his post, I will say this: I don’t quite know why Monckton has the impression Kiehl and Trenberth 1997 have an “implicit λ0 is 0.18”. Nor do I know why he thinks I “She was … selective in not passing on that I had told her they were wrong to assume that a blackbody relationship between flux and temperature holds at the surface”.
Since Monckton these issues up reporting them as having been discussed in our email exchange, I would be willing to have a conversation about these. But I think any such conversation would best accompanied by the emails themselves.
A 15 degree climate range shown in the article therefore implies 15 doublings of CO2 (or equivalent forcing) at 1 degree per doubling. 2 to the 15th is 32000, so the difference between the lowest CO2 values and highest would need to be a factor of 32000 or equivalent forcing (maybe albedo helps at the cold end, but ignoring the cooler periods we still can get 2 to the 8th which is 128). So this is the amount that CO2 would have to be larger than the low-end values (near 200 ppm) to account for the described range with a 1 degree per doubling feedback. CO2 levels in the last few hundred million years have not exceeded 20 times the current values. It just does not work. The feedback has to be much higher for a factor of 20 in CO2 to have as much effect as 15 degrees: somewhere in the range of 3-4 K per doubling.
James–
I don’t know why you think I’ve attacked Monckton. I have criticized the derivation of a mathematical-physical result he reported in his letter to RS. I explained at some length that the derivation is unreliable. I don’t consider this an attack.
To the contrary. In my initial email to Monckton, I enquired how he’d derived an equation he used. We discussed this. After examining Kimoto– which is the derivation he seems to insist he follows– I wrote my blog post criticizing the derivation in Kimoto. Go read my post.
I did err in thinking that Monckton had refused to supply the full citation. That meant I had to hunt down the reference before reading it and criticizing it.
“”””” Tsk Tsk says:
September 27, 2011 at 8:59 pm
Craig Goodrich says:
September 27, 2011 at 5:13 pm
One circuit parameter of great importance is the (closed) feedback loop gain inside any amplifier, which must be held at less than unity under all circumstances to avoid runaway positive feedback (g ≥ 1).
It took a bit to realize that what was meant here is, in electronic terms, the effect of closing the feedback loop on the amplifier, that is, the ratio of the closed loop gain to the (theoretical) open loop gain of the amp. A typical power amplifier might have a (theoretical) open loop voltage gain of 10,000 — theoretical because it would fry both itself and anything it was connected to if it were run that way —
—————————————————
Actually it wouldn’t fry itself and anything it was to which it was connected, or at least not as long as the load was larger than the minimum required for the power stage of the amplifier. A dead short on the output could do bad things depending on the amp used, but assuming you have a sufficiently large resistive load all that would happen is that the amplifier would go to one of its rails depending on the signal you were injecting and assuming you simply put a reference on the other input terminal. “””””
Well tsk-tsk, I could say the same to you. Feedback amplifiers don’t have to fry themselves or anything else whenn you put a dead short on the output. Many of them are designed specifically to operate into a dead short.
You obviously are not a process control geek, or the very common 4-20 mAmp current loop would be old hat to you. Yes a short is bad for an Amplifier whose output is supposed to be a Voltage; but a great many are designed to provide a current output, and they operate best into a dead short.
You can run a current signal over miles and miles of wires and get absolutely no signal loss at the other end. Of course you have to use a quality insulated wire so there is no current leakage; so nyet on the badness of shorts.
The very last feedback amplifier I have designed is in fact a current output Amplifier. It also has a current input signal; namely the photo-current from a very low noise photodiode; which is integrated on the same Analog CMOS IC.
99.99% of all photodiode amplifiers are photocurrent to Voltage converters, so they have a Transimpedance gain rather than a Voltage gain. They get this by incorporating a high value feedback resistor from the output node to the inverting input node, where the photodiode is also connected.
They do this because the majority of so-called analog designers are brain dead, and they were taught by equally brain dead professors or instructors that that was the right way to do it.
Problem is you can’t put a 0.1% accuracy 100 megOhm resistor onto any CMOS process IC chip, and to put such a resistor externally, you have to have a connection pin to that input current summing node; and that “pin” has to have all the usual “pin” protection circuits connected to it so electrostatic discharges don’t zap the amplifier.
The input capacitance and noise penalty that reults means a very ho-hum gain bandwidth product and a low performance photo-detector amplifier.
But you can incorporate a roughly 100 megOhm but quite non-linear resistance in the form of a P-Channel FET. Actually, you incorporate two P-FET resistors, a high value, and a much lower value. And the circuit architecture maintains exactly the same Voltage across both resistors at all times, and you end up with a feedback amplifier that has a controlled current gain, instead of a Voltage gain or Transimpedance. And you use multiple copies of the same low resistance P-FET, to get the 100 megOhms, and the gain is simply the ratio of those two resistors, which is simply the number of “kit” fets that form the high resistance. And because they both have the same Voltage across them at all times, they have the exact same non linearity, so even though the resistors are non-linear, the current gain is quite linear. And because you didn’t bring the summing node to the outside world, you don’t need any pin pad protection becaue there is no pin.
So the summing node capacitance can be extremely low, so you get a very high gain bandwidth product that you can’t even approach with a Transimpedance photo-amplifier. The one I designed has a current gain of 500 from the input photo-current to the short circuit output current; and I don’t know of a higher gain bandwidth photo-amplifier anywhere. This one is a very low current (fempto-Amp) photo-signal, and around one MHz for the 3dB bandwidth.
Current gain feedback amplifiers are also inherently more stable than transimpedance designs; but as I said most designers are brain dead.
It so happens, I also used a current feedback amplifier for the very first transistor circuit I ever designed around 1957. Quite primitive compared to the latest one.
So shorts are ok for current out amplifiers, and often preferred for process control loops because of the ease of propagating signals over long distances. Of course today, you can also do the A-D conversion thing and send ones and zeros
lucia says:
September 27, 2011 at 9:27 pm
My technical claim at my blog is that the method derived in Kimoto (and relied on by Monckton)
=================================================
This is entirely without merit.
First and foremost, Lucia, you are implying that Monckton’s entire comment to RS rests on Kimoto. It does not.
Later you state, “Unfortunately, Monckton did not engage any of the technical points in my post. He wrote a he-said/ she-said discussion of the email exchange instead. “…….. That is most incredulous. I understand defending yourself, as well you should, but don’t pretend you didn’t participate in such.
Your comment,“But this section in Monckton’s main post discusses my blog post without engaging my technical points, but instead resorts to discussing what was communicated in the emails about these claims….”
Well, how would you expect a person to respond? First on the technical issues or the attack on character? That’s the dumbest damned statement I’ve ever seen from you. I would defend my character first, before defending my maths.. I think most rational people would.
Gail Combs says:
September 27, 2011 at 5:34 pm
Legatus says @ur momisugly September 27, 2011 at 4:16 pm
“…A recent poster on this site, who works with observatories telescopes, pointed out that they make just such direct measurements of the infrared radiation….”
_________________________________________________________________________
It would be nice if you could give us a pointer to that comment or at least a name.
IAmDigitap says:
September 20, 2011 at 3:42 pm
[SNIP: Anthony has already stated that this is an over-the-top rant and has no place on WUWT. Do not try and sneak it in via a back door. -REP, mod]
(when I posted it to the tips and notes section as interesting data contained in the rant that was of crucial, even central importance)
I am unable to point to it since i has been snipped, as you can see here. It was indeed rambling, however, in it IamDigital said that he worked with telescopes, some of them infrared telescopes, and that they needed to know what the infrared was to tell how much to flex the telescopes to adjust for the distortion of the atmosphere from heat. He stated that they now have to adjust for heat slightly less than they used to. This means there is less infrared radiation. This is also seen by the infrared telescopes, which, of course, can see infrared.
IamDigital should repost something, this time without all the ranting, in a more coherent and organized form, and with DATA. If he really feels emotional enough to make such a rant about this subject, well, now he know what to DO about it. rants will get you nowhere, science will.
Note to moderator, at the time I posted this, the post had not been snipped. Since it was unsnipped, and had been passed onto these boards in the first place after having been previously seen by a moderator (and thus I saw no reason to think it would then be snipped by somone else later, which is what happened), I was not trying to “sneak it in via a back door”, since it had not been snipped at that time. Or do I have to resort to the wayback machine…
However, whether that original was written in rant style or not, my original idea stands.
The very basis on which all of global warming theory stands or falls is based on increasing CO2 causing increasing infrared rediation.
This infrared radiation can be measured directly, and is being so measured at observatories.
They keep records of that sort of stuff (at least, as scientists, they are supposed to).
We can, therefore, compare old records of infrared radiation to current ones.
We know that there is more CO2.
If there is not more infrared radiation, than the basis upon which all global warming theory rests has been scientifically falsified.
Is there something wrong with this as a scientific hypothesis complete with proposed experimental method using already existing equipment and even existing records?
What, exactly?
And why has this not been done yet?!?
Why has this not even been suggested yet?!?
Thank you, Christopher Monckton! Thank you, Anthony! Thank you, Lucia! And thank you to all of the participants above!
This has been one of the most engaging and enjoyable discussions on WUWT. Much food for thought and much that is useable to educate legislators and believers alike.
Interstellar Bill says:
September 27, 2011 at 8:47 pm
Legatus
You presume the Warmistas are amenable
to scientific argument via measuring the sky’s LWIR,
when actually they are self-blinded ideologists
Who cares what the ‘warmistas” think about this, this is about science. There are some people who will be interested in this DATA. the people who read THIS SITE. Lots of people, some scientists, some amature scientists, some correspontants (James Delingpole comes to mind) some regular citizens. If this is science, just throw it out there, the people did not at first believe Galileo, they do now. It has to start somewhere. What if Galileo had just kept it to himself and never told anyone? What if all scientists had done that?
I’ve done lots of of infrared sky-temp measurements,
thirty-five years ago, and today, with the same pyrgeometers.
Their unchanged readings contrast sharply
with Alarmism’s computer-predicted increases.
Well, lets see some DATA! Why not take this data, which is central to the whole global warming idea, and make a guest post? If Willis can do it, you can do it. After all, YOU have the DATA.
Similar computer simulations show that a hypothetical doubling of the carbon dioxide concentration in the air would cause a 3% decrease in the absolute humidity, keeping the total effective atmospheric greenhouse gas content constant, so that the greenhouse effect would merely continue to fluctuate around its equilibrium value. Therefore, a doubling of CO2 concentration would cause no net “global warming” at all.
It’s long been my suspicion this is the case. If true it invalidates the Forcings Model and therefore the climate models.
The Earth’s climate does change over periods of decades to a few hundred thousand years. Periods too short to be caused by plate tectonics moving continents around, which begs the question, if changes in radiative forcings don’t cause climate change, what does?
The only answer I can come up with is something that affects the phase changes of water. Changes in GCRs being a possible mechanism.
It’s important to understand that the Radiative Forcings Model/Theory gained acceptance because it was the only theory that could explain the fact the climate changed. Not because of any evidence it was correct.
This is still the situation today, and the reason for many of the adjustments, assumptions of measurement error, and search for the missing heat. For most scientists, a bad (or flawed) theory is better than no theory at all.
I see Monkton’s paper as a critique of the Forcings Theory predicting a 3C+ temperature increase from 2XCO2. Not an argument that the evidence supports a ~1C rise and by extension the Forcings Model is correct.
According to Monckton I am a “troll” for claiming that Monckton has “…’fabricated’ the forcing function for CO2.” In crafting his characterization of me, Monckton erects and knocks down a strawman by misrepresenting what I have actually said.
I do not say that Monckton has fabricated a “forcing function.” I do say that Monckton has fabricated “information.” “Information” is not a “forcing function” hence Monckton has misrepresented what I have said.
The information which Monckton has fabricated is of the existence of a functional relation that maps increases in the atmospheric CO2 concentration to increases in the global equilibrium surface air temperature. As the equilibrium temperature is not an observable feature of the real world, Monckton’s assertion of the existence of a functional relation is non-falsifiable thus lying outside science.
Though Monckton disagrees with IPCC Working Group I on the sensitivity of the equilibrium temperature to the CO2 concentration he agrees with them on the existence of a functional relation. This contention is, however, scientifically untenable for the existence of a functional relation is insusceptible to being refuted by reference to observational data from the non-observability of the equilibrium temperature.
While Monckton’s allusion to trolls is cute, it distracts the audience’s attention from the scientific issue. Is he prepared to address this issue?
lucia says:
September 27, 2011 at 9:36 pm
James–
I don’t know why you think I’ve attacked Monckton……….. Go read my post.
==================================================================
Lucia, I didn’t see your comment before I posted the one prior to this one. My verbiage certainly would have been different. Feel free to regard or disregard the comments to my post prior to this one. Any questions I would answer. I am at your mercy in this regard.
I have read your post(s). Lucia, it is quite plain to me that we don’t see things the same. It is to the pity. Lucia, I’ve great respect for your numerical intellect. I can not fathom how or why you don’t apply it towards the loss of humanity or humanity’s loss.
But more, you’ve the knowledge. You have the ability. And you have the proofs. There is an entire nation that turns their eyes to you. And you quibble with Chris Monckton. Why? Isn’t there something else to be doing? Are you going to pontificate about Monckton’s conformity to accepted science? Or, are you going to do something?
James
lucia says:
September 27, 2011 at 9:36 pm
James–
I don’t know why you think I’ve attacked Monckton.
Monckton Planck Parameter: No better than pulling numbers out of a hat.
That title strikes me as more than a bit pejorative. I don’t know if someone directed such a post at me if I would necessarily consider it an attack (in my case it might be likely to be true) but you ought to able to recognize that Monckton and those who don’t hold the same dim view of him that you appear to, might be less understanding, given his situation.
Willis Eschenbach says:
September 27, 2011 at 5:29 pm
****************************************
Willis – you may be right, but I think Christopher Monckton is just doing what he has been doing all along – hoisting climate alarmism with its own petards.
All the best.
Doug says:
September 27, 2011 at 3:35 pm
“In the Neoproterozoic, 750 Ma BP, CO2 concentration (today <0.04%) was ~30%: otherwise the ocean’s magnesium ions could not have united with the abundance of calcium ions and with CO2 itself to precipitate the dolomitic rocks laid down in that era"
I would be very cautious in making that statement. It is very common for carbonates to be diagenetically altered to dolomite long after deposition. Even with much younger, unaltered rocks, it is difficult to ascertain when the dolomite was formed–at time of deposition or later. There are numerous papers on the subject and the determination of early vs late dolomite is the subject of many days of discussion in a typical graduate level carbonate petrology course. I would look for a more robust proxy.
****************************************************************************
Doug, and Chris,
Doug, diagenesis in a rapidly-deposited carbonate sequence like that in the Cryogenian would likely occur reasonably quickly simply due to burial-depth increasing quickly. From what I have read, at least some of the dolomite of that age is a primary feature, pointing to some unusual seawater chemistry at the time.
One mechanism for development of an "aragonite-dolomite sea" would be enhanced weathering episodes. These may, for example, occur after large-scale volcanism, orogenesis or major eustatic sea-level falls – the latter an expected occurrence in glacials, of course. Weathering is a major carbon dioxide sink and a enhanced weathering can lead to a major CO2 drawdown: carbonic acid (i.e. carbon dioxide dissolved in rainwater/groundwater) attacks minerals, the most unstable of which dissolve readily and release cations to the aqueous system. The last major weathering episode likely brought about the end of the Cenozoic "hothouse" climate and led to the onset of Milankovitch-driven glaciations in the Quaternary.
Older glacial episodes such as the Cryogenian may well have been influenced in their fluctuations by Milankovitch cycles: do not forget either that solar output was several percent below that of the present day, too: in essence we had a different planet back then.
Chris, this paper published a couple of years ago in the Australian Journal of Earth Sciences:
http://www.tandfonline.com/doi/full/10.1080/08120090903005378
is of interest because it details the stratigraphy of one of these Neoproterozoic sequences, in the Flinders ranges. It suggests that the thick carbonate sequences lie in between glaciogenic sequences – diamictites etc – and raises the possibility that they were deposited during interglacials: it does not appear that said interglacials were as short as those of the Quaternary. During glacial retreat, sea-levels rose and flooded low-lying areas where carbonate reefs developed: these were subsequently destroyed during reglaciation and sea-level falls. Abstract:
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A detailed sedimentological and chronostratigraphic analysis of the Umberatana Group in the northern Adelaide Geosyncline has uncovered a depositional history involving the rapid progradation (at least 20 km) of a giant reef complex (up to 1.1 km relief) during mid-Cryogenian interglacial times. The reef complex, which occurs in the Balcanoona Formation, displays facies similar to Phanerozoic reefs. These include a basal forereef (slope) facies, overlain by a reef-margin facies (consisting of both stromatolitic and non-stromatolitic frameworks), and an upper backreef (platform) facies consisting of shallow-water peloidal and oolitic carbonate. The thickening of the reef complex in a basinward direction, and the distribution of the key facies are consistent with the progradation of the platform into deep water. Progradation was contemporaneous with deposition of the upper Tapley Hill Formation and had largely ceased after a major margin failure event. Following this event, reef growth continued for a short time before becoming extinct, possibly as a result of global climatic cooling and/or eustatic sea-level fall.
************************************
Note that these carbonates tend to display a conformable relationship to the glaciogenic sediments they overlie, but their tops are in unconformable contact with succeeding glaciogenic rocks, in some cases with karstification of the carbonate palaeosurface. This would all be consistent with sea-level rise and fall in a glacial-interglacial-glacial cycle, just as we have seen in more recent times, with the estimated 120m sea-level rise following the last glacial maximum and subsequent deglaciation. I would be interested to see if any detailed reconstruction of carbon dioxide levels across these Neoproterozoic cycles is possible – the further back in time one goes, of course, the more difficult that is.
Regards – John
Down here, where the ice that is supposeldly melting is (which would cause the sea to rise, when we see that it is dropping) is where we need this measurement. This is where they say the danger of global warming is, hence why we need to measure down here (also around a few glaciers I suppose). This is also where supposedly species will go extinct from too much heat (also not happening). Besides, we have already measured the atmosphere at all altitudes to see if the air is heating up, such as at 10 kilometers altitude in the tropics, which, occording to global warming theory, must be heating up with increased CO2, yet is not.
If they make these things, someone must be using them. If they are scientists, they keep records. Well, could I see some? Then, we can compare the amount of infrared radiation to the increase of CO2, and see for ourselves if infrared goes up with increasing CO2. Then, we can release these two graphs (incrweasing CO2 and increase or lack thereof for infrared) together as our own “Hockey stick”, complete with the same hype. This time, it would deserve the hype.
I just don’t get it.
Global warming theory is BASED around more CO2 causing more infrared radiation down here, causing things to heat up.
When I search in google for Pyrgeometer, I get 33,200 results http://www.google.com/search?q=Pyrgeometer&hl=en&num=10&lr=&ft=i&cr=&safe=off&tbs=
Yet, no one thinks to use these things, or to obtain the direct measurements of this, the very heart of the whole theory of global warming, the infrared radiation, when we can so easily do so, and have been able to do so for many years?
It is as if we decided to never measure air temperature with thermometers of any kind, but instead decided to only do indirect measurments, say, estimates of the temerature from, say wind shear (oh wait…).
We have the capability to confirm or falsify the whole global warming theory NOW, why have we not done so?
It would also be interesting to see what the reaction is in certain quarters if they discoverd that people were seeking their Pyrgeometer readings over time, would it take a freedom of information act, would even that work? I mean, I would like to know why no one has tried this very simple and oh so very OBVIOUS experiment.
Global warming can be directly measured by existing instruments.
If we can do so, and find no increase in infrared over time.
We should take that gun, point it right at the heart of the whole idea, and…
BLAM
DEAD
IT’S OVER
And then we can get on with our life.
Or we can continue to pussyfoot around with indirect measurements, proxies, models, obscure studies many of which will never be heard of, and, basically, what we have been doing…
What a brilliant posting and debate. Speaking only as an armchair / pseudo scientist I think I can say this is one of those occasions where we are beginning to see more light than heat.
Somehow, the top part of my post above got snipped in pasting, this is it:
Grey lensman says: (about measuring infrared radiation directly over time and seeing if it goes up with increased CO2)
September 27, 2011 at 7:41 pm
The weak point in my view is that these instruments are not at the surface but high on mountain tops.
Uh, they don’t have to be, look here.
http://en.wikipedia.org/wiki/Pyrgeometer
It appears that it can be measured by this releatively small and possibly even relatively cheap (compared to, say, giant telescopes) device.
Lord Monkton, have you seen:
– On the observational determination of climate sensitivity and its implications (PDF)
(Submitted to Journal of Geophysical Research, February 2010)
– Richard S. Lindzen, Yong-Sang Choi
http://www.legnostorto.com/allegati/Lindzen_Choi_ERBE_JGR_v4.pdf
I don’t know if it was eventually published or not, but passing it along in case it might be useful for you.
If you haven’t already, you might want to take a run thru the papers listed at: http://www.populartechnology.net/2009/10/peer-reviewed-papers-supporting.html#uds-search-results
to see if there might be any of interest.
Legatus says:
September 27, 2011 at 4:16 pm
/////////////////////////////
I have seen this point made several times before. It seems an inportant point, however, I have not seen any empiral observational data backing this up. Has any one compiled a data set covering the last 20 to 30 years?