1 A Critical Examination (December 18, 2012) by Dr D Weston Allen of: A Discussion on the Absence of a Measureable Greenhouse Effect By Joseph E Postma (October22, 2012) Introduction: After two earlier papers attacking the Greenhouse Effect (GHE), Understanding the Thermodynamic Atmosphere Effect (March, 2011) and The Model Atmospheric Greenhouse Effect (July 22, 2011), both of which I have critiqued, Joseph Postma now presents this comprehensive assault on the theories of global warming by atmospheric greenhouse gases (GHGs): heat trapping, backradiation and elevation of the radiative emission level. Over three weeks after I sent this critique to him via John OSullivan, Postma responded, but only to my introduction and last paragraph of the conclusion nothing in between. I have therefore clarified the statements and mathematics that he struggled to comprehend and added much of his response (in blue) to this introduction. In the Introduction to his Absence paper, Postma points out that the GHE is supposed to explain the 33C difference between Earths mean near-surface-air temperature and the global effective blackbody temperature calculated from the absorbed energy from the sun. He then takes the novel approach of postulating what would happen if there were no GHGs in the atmosphere. He first shows that Earths albedo (reflectivity) would not be 0.3 (30%) but just 0.04, in which case the calculated surface temperature would not be 33K below the observed mean but only 12K less. He overlooks the fact that atmospheric aerosols and major gases also reflect and absorb solar rays, however, and also that the surface albedo of 0.04 relates to the solar flux at the top of the atmosphere (TOA). Removing the GHG/cloud filter would allow a greater percentage of TOA flux to reach the surface and thus be reflected there, in which case the surface albedo would be more than 4% of the TOA flux. Such basic logic seems lost on Postma: This author doesnt even know how to kindly address this. It is one of the stupidest things I have ever read, and exposes the fact that Wes probably has no understanding of the meaning of the term albedo. Whereas Postma calculates the mean surface temperature of a sunlit hemisphere with an albedo of 0.3 and no atmospheric absorption to be +49C, my calculations put it at 34C; and at just 5C with atmospheric absorption (and no GHE). That is about 10C below the observed mean for the entire half-dark planet. But Postma objects: Wes does not actually provide any explanation for how he arrived at his values, and so we might only assume that he is guessing at them out of thin air. The relevant section in my paper clearly describes how I calculated the value I did: the instantaneous average heating potential of sunlight over the sun-facing hemisphere, assuming an integrated albedo of 0.3, has a hemispherically integrated average value of 322K or +49C. If that clearly describes Postmas method, Ill eat my hat! I had given at least the equivalent explanation. For Postmas sake, and to leave the reader in no doubt, however, I have now fully explained the science and maths behind my figure of 34C on page 7 of this critique. Postma says the 33K attributed to the GHE can be explained by the lapse rate (reducing temperature with increasing altitude), which he derives from first principles without reference to a GHE. He now asks: does Wes care to argue that the successful derivation of the dry lapse rate only coincidentally matches that of what is observed? Whereas the derived dry adiabatic lapse rate is ~9.8K/km, the observed mean is ~6.5K/km. Is that a coincidental match? Ignoring the term adiabatic, Postma confuses the moist adiabatic lapse rate with the observed environmental lapse rate, both in his paper and in his response: This is a great example of the type of sophistry that frauds enjoy to use 2 in their multifaceted obfuscations in all things science-related. The observed environmental lapse rate and the moist lapse rate are entirely the same thing. Are they really? The moist adiabatic lapse rate is only ~5.5K/km. It relates to fully saturated air whereas the environment is only partly saturated with water vapour. Whenever Postma is caught out, in this case using incorrect terminology, he forgets truisms about judging others as oneself or pointing the finger, and accuses his critic of sophistry, a subtle, tricky, superficially plausible, but generally fallacious method of reasoning. Guestimating the water vapour at Earths surface to be 2.5%, based on Wikipedias range of 1-4%, Postma calculates an environmental lapse rate of 6.24K/km; and then works backwards from 6.5K/km to determine a mean water vapour content of 2.29%, over 8% below his guestimate. He nevertheless asserts: The calculations I presented between pages 7 and 9 of my Absence paper were a demonstration of the ability to successfully predict the average environmental lapse rate given the known surface-level water vapour concentration, and an estimate for the height of the troposphere and vapour concentration therein. Local conditions will of course vary, and the calculation using average-known values was entirely successful at predicting the observed rates. When calculating the impact of latent heat on the lapse rate, Postma assumes that it is linear, that the atmosphere is in hydrostatic equilibrium and that the tropopause is at a fixed altitude. He overlooks the non-adiabatic absorption and emission of infrared radiation by atmospheric GHGs and their role in assisting the heat pump that drives the lapse rate, in rendering it more uniform and in determining its extent. Instead of properly addressing this, Postma prefers innuendo and ad hominem: Here, Wes seems completely oblivious to the concept of physical averages. This is not surprising since he is unfamiliar with the appropriate usages of mathematical averaging, as evidenced by his support for flat-earth models of the terrestrial environment as so much from the dark ages, and his apparent lack of undergraduate training in math and physics. . . Undoubtedly, this is why Wes prefers to deny, yes, deny, in one of the absolute worst of possible human ways, standard mathematics, physics, and logic. It is the denial of rationality itself, representative of the gnostic demiurge. Are these the words of a scientist or of an offended religionist? For the record, I excelled in my undergraduate maths and physics; but the veracity of any argument or insight is not based on the qualifications of the protagonist. Einstein is a prime example. In his second section, Postma uses heat-flow mechanics and time constant (tau) values incorporated into a formula in which a surface cooling variable (for conduction, convection, evaporation etc) was removed (contrary to his text) and replaced with a second GHE warming variable. He used this to produce impressive surface temperature graphs using selected GHE variables. His modified formula [16] is thus fundamentally flawed and hence his temperature responses are positively biased. Postma responds: Wes seems to understand nothing of what was actually presented with that equation and its modelling. First, Wes seems to think that the heating strength of the GHE must at all times be equal and opposite to the cooling strength of the air! This is absurd beyond belief, as it was discussed in my paper. Just look at the cognitive dissonance and the abuse of logic in this: the atmospheric GHE causes heating, but observing it is impossible because the atmosphere causes cooling. !!! This is a perfect example of Satanic thinking, a perfect example of the gnostic characterization of the demiurge. Postma puts words in my mouth and then condemns them, even labelling them Satanic thinking! Postma himself is guilty of cognitive dissonance in his Absence paper, emphasising conduction of heat to the atmosphere when it suits and forgetting all about it when it doesnt. Does he now deny any conductive cooling of Earths surface by the atmosphere? Thoughtful readers could be forgiven 3 for wondering why I bother with Postma: even if he is beyond reason, I sincerely hope that some of his devoted followers arent. Postmas third section compares the GHE graphs produced using his flawed formula to those based on observations made by Carl Brehmer at Chino Valley in Arizona over two days in June 2012. Of course Brehmers findings dont support Postmas contrived GHE graphs; but Postma ignores conduction, convection and humidity. When these are factored in and Brehmers data is carefully analysed, it strongly supports the GHE. Postma responds: It is very clearly derived how the GHE should be observable [from his flawed formula]. It wasnt observed [at first glance]. And so therefore GHE advocates do a volteface [sic] on the entire matter and now claim that the atmosphere is *such an efficient cooler*, that it cancels out any heating effects of the GHE on the surface! Yes, such is the nature of the laughable sophistry of Dionysus. Again the Postma calls the kettle black. Whereas GHE supporters have always recognised that the atmosphere cools Earths sunlit surface by conduction, and factored it into their energy budgets, Postma paints them as doing a volte-face on the matter. And he does so to obscure the fact that he completely overlooked conductive cooling of the surface in Brehmers experiment. There is very little relevant science and a great deal of sophistry and philosophy in the remainder of this rather lengthy paper. Precious Postma takes great umbrage at this comment: on the very first page of his critique he himself makes an ad-hominem, patronizing, and judgemental comment. If you have wondered why I have not been kind to Wes in this review of his review, it is for this reason. Wes is simply not a competent scientist or mathematician nor can he understand or critique standard scientific research in a competent let alone professional way. It is a waste of my time to attempt communicating scientific concepts with ideologues such as this and I wish for my judgement on this matter to be blatantly understood. I admit that my statement was judgmental of Postmas paper but not of his person, learning or integrity. It was not in the least ad hominem. He assumes that I was referring to his arguments, rather than those he quotes, as sophistry. Unable to differentiate criticism of his paper from that of his person, Postma lashes out with actual ad hominem that I find quite amusing. I am delighted that he could find no fault with my critique other than a couple of poorly worded sentences, but disappointed that he could not bring himself to admit a single error or concede a single point. His emotional response to my critique reveals a greater concern for ego than for science. Instead of the absence of a measurable GHE, Postma unwittingly presents strong evidence to support it. (Quotes from Postmas Absence paper are hereafter highlighted in red.) 4 1. Introduction to the GHE 1.1. The problem, and truth, of the albedo Generally, the inference of an atmospheric GHE is made by comparing the Earths near-surface-air average temperature to its global effective blackbody radiative temperature calculated from the absorbed energy from the Sun there is a difference of 33K. There exists a simple contextual flaw in this inference because the average terrestrial albedo is much higher than the true surface albedo due to the presence of clouds in the atmosphere, resulting in a terrestrial albedo of approximately 0.3, while the true surface albedo is actually much less at only 0.04 [3]. That is, without greenhouse gases, the albedo would not still be 0.3, but 0.04. . . . It should be noted that the much higher albedo, with GHGs present, is caused by the presence of clouds from droplet-condensation of the GHG water vapour. [p.3-4] Postma bases this figure of 0.04 on Donohoe and Battisti (2011),1 whose satellite data confirmed earlier modelling that the vast majority of the observed global average planetary albedo (88%) is due to atmospheric reflection. While the remaining 12% (of the total 0.3) occurring at the surface is indeed only about 0.04, Postmas conclusion is wrong for the following reasons: 1. Across Earths varied surface, the albedo is greater than 0.04 everywhere except over still water with an overhead sun. The albedo over land areas is mostly in the range of 0.1 to 0.4 (increasing from forest to grassland to desert sand, consistent with the value of 0.26 obtained by Carl Brehmer and quoted by Postma on page 26); over water it ranges from 0.035 to 0.38 (as the sun sinks from 90 to 10 above the horizon); over ice it is 0.5 - 0.7 and over snow 0.8 - 0.9. The mean surface albedo is therefore much greater than 0.04. On page 5, Postma himself postulates a surface albedo of 15% (0.15) with no clouds in the way. 2. The figure 0.04 means 4% of solar radiation at the top of the atmosphere (TOA), not 4% of that reaching the surface. In addition to the 26% reflected by the atmosphere, another 20% or more is absorbed by it, much of it by greenhouse gases (GHGs) and clouds. Over a third more solar radiation would reach Earths surface if there were no GHGs, particularly water vapour; and so more than 5% of the TOA flux would be reflected at Earths surface. 3. Solar radiation is also scattered / deflected by the major gases, nitrogen and oxygen, by Rayleigh Scattering (discussed by Postma on page 26). This is inversely proportional to the fourth power of the wavelength, which is why the shorter blue wavelengths are scattered more than red, and Earth looks blue from space. Atmospheric dust, sulphur and other aerosols also reflect sunlight. The combined effect of this scattering is thought to contribute as much as 0.06 (6%) to Earths albedo and clouds 20% (Fig. 1). Figure 1: Interaction of Solar Radiation on Earths Atmosphere and Surface Source: http://www.ucar.edu/learn/1_3_1.htm (I have been unable to find corroborating evidence for this figure of 6%) 5 Water droplets in clouds, of course, have nothing to do with water vapours GHE. Being unrelated to GHGs, this ~0.06 would need to be added to the surface albedo in Postmas scenario. Without any atmospheric greenhouse gases, therefore, Earths albedo would be much greater than 0.04, at least 0.1 and probably about 1.2. Indeed, Donohoe and Battisti point out that the atmosphere attenuates the surface albedo by a factor of 3. Therefore a valid comparison is actually found in the theoretical temperature of the Earth-ensemble without greenhouse gases (GHGs) and with a correctly corresponding albedo, to that with greenhouse gases with their corresponding albedo. In this physically meaningful comparison, the difference in temperature between the theoretical ground surface, and the observed surface with an atmosphere and GHGs on top, is only 12K, reducing the inferred strength of the GHE by almost two-thirds. That is, the average global surface temperature without GHGs, calculated using the usual method of the Stefan-Boltzmann Law with conservation of energy given the known solar input and the surface-specific albedo, results in a value of 276K. The observed average surface temperature with GHGs present is actually 288K (15C), and so the greenhouse effect should actually be thought to only provide 12K worth of additional temperature, not the 33K which is always incorrectly cited. [ibid] Postma doesnt say exactly what known solar input he uses. Recent measurements put it at 13633 W/m2, but his appendices indicate a reliance on 1370 W/m2. I use 1368 W/m2 in my calculations. Postmas albedo of 0.04 leaves ~1313 W/m2 to warm Earths surface; spread evenly over the globe by dividing by four gives ~328 W/m2 from which the Stefan-Boltzmann equation gives an equilibrium temperature of ~276K (3C). Had Postma used an albedo of 0.1, he would have derived a surface temperature of 271.4K; and an albedo of 0.12 would result in a temperature of ~270K, 18K below the observed mean. Although Postma mentions the absorption of solar radiation in the atmosphere, he ignores it in his calculations. Only about half of the absorbed solar radiation is in the infrared spectrum (Fig. 2). Figure 2: Solar Radiation Spectrum at Top of the Atmosphere (yellow) and at Sea Level (red). Source: http://en.wikipedia.org/wiki/File:Solar_Spectrum.png At an altitude of 100-200km, almost all wavelengths shorter than 100 nm are absorbed by molecules of oxygen and nitrogen, resulting in electronic transitions into atomic ions. The upper mesosphere absorbs the Lyman-o radiation at 121.6 nm. Photodissociation of oxygen absorbs the Schumann-Runge continuum (130-175nm) at 80-120km altitude, and the 175-200 nm band is absorbed by photodissociation and vibrational transitions of the oxygen molecule at an altitude of 40-95km. Oxygen atoms and molecules combine in the stratosphere to form ozone, which absorbs about 99% 6 of the UV shorter than 320nm.2 This, of course, is unrelated to any IR-absorption by ozone. Joanna Haigh describes these absorption bands in The Sun and the Earths Climate: The oxygen Herzberg continuum is found in the range 200 242 nm and is overlapped by the ozone HartleyHuggins bands between 200 and 350 nm which are responsible for the photodissociation of ozone below 50 km. The ozone Chappuis bands, in the visible and near-infrared, are much weaker than the aforementioned bands but, because they absorb near the peak of the solar spectrum, the energy deposition into the atmosphere is significant. Furthermore, this deposition takes place in the lower atmosphere and so is particularly relevant for climate. The absorption of solar near-infrared by carbon dioxide and water vapour is smaller but makes an important contribution to the heat budget of the lower atmosphere. 3 The altitudes of these absorption bands and the gases responsible are illustrated in figure 3. Figure 3: Wavelength dependence of the altitude of one optical depth for absorption of solar radiation with an overhead Sun. After Andrews (2000). Oxygen also absorbs about 2 (0.9-3.11) W/m2 of solar energy in the 300-1300nm band.4 Aerosols not only reflect solar radiation to space but also absorb it, mostly in the visible spectrum, resulting in global dimming. Based on visibility measurements at 3,250 meteorological stations around the world (and satellite data from 2000 to 2007), Wang et al (2009)5 found a steady global increase in aerosols from 1973 to 2007, except over Europe which experienced global brightening. The percentage of TOA solar flux absorbed by the atmosphere was thus increased to 22.9% in 2008.6 If we accept a terrestrial non-GHG albedo of 0.12 and non-IR atmospheric absorption of 11.5% of the TOA solar flux, only ~281 W/m2 would reach the surface, sufficient for a temperature of ~265K, or 23K below the observed mean. If we accept an albedo of just 0.1 and a third of atmospheric absorption (7% of TOA flux) as being unrelated to GHGs and clouds, this would result in ~295 W/m2 being absorbed by the surface and a temperature of 268.5K, still 7.5K below his 276K. Although Postma discusses the emissivity of Earths surface, he fails to factor it in. A conservative emissivity of 0.96 would increase the surface temperature from 268.5K to ~271K, still 5K below Postmas 276K and 17K below the observed mean. A very significant difference remains to be explained. On page 5, Postma points out that, viewed from space, Earth has an apparent blackbody temperature of 255K, which is the temperature of the average radiating emission altitude . . . between 5 and 6 km. . . . exactly the temperature it is supposed to be. Of course! 7 He further explains that temperature increases with depth below this layer because the bulk source of heat energy . . . comes from solar radiation generating heat at the bottom-most layer of the atmosphere, at the surface-atmosphere boundary. He then correctly calculates that with a surface albedo of, say, 15%, and no clouds in the way, the real-time insolation temperature works out to ~378K or 105C, via the Stefan-Boltzmann Law. [But he then continues] As a matter of fact, the instantaneous average heating potential of sunlight over the sun-facing hemisphere, assuming an integrated albedo of 0.3, has a hemispherically integrated average value of 322K or +49C. Responding to my initial draft of this critique, Postma stated: There is nothing that is physically or mathematically ambiguous about this statement, unless the person reading it is entirely devoid of knowledge of undergraduate-level science and mathematics. I had stated: According to my calculations, the mean solar flux over a hemisphere with no atmospheric absorption and an albedo of 0.3 would be ~479 W/m2 and the corresponding temperature would be ~307K or +34C. Since Postma then makes the accusation: However, even with Wes guessed at value of +34C . . ., here are my calculations: TOA solar flux 1368 W/m2 Minus albedo of 0.3 ~ 410 W/m2 = Absorbed flux 958 W/m2 This would be the flux absorbed over a cross-section of Earth through the centre (i.e. a disc), not a hemisphere, which has a surface area twice that of its base (disc), so we have to halve this figure: = 479 W/m2 To determine the average hemispheric temperature from this insolation, we use the Stefan-Boltzmann (S-B) equation: E =oT4 (W/m2) Where E is radiated energy, T is in Kelvin (K) and o is the Stefan-Boltzmann constant: ~5.67 x10-8. For a blackbody in radiative balance, outgoing radiation equalling incoming radiative flux, the temperature produced by incoming radiation can thus be derived: T = (E/o)4 For a grey body such as Earths surface with an emissivity (c) less than 1, the S-B equation becomes: E =coT4 and T = (E/co)4 Assuming an emissivity of 0.95 for Earths surface, T = (479/(0.95x5.67x10-8))-4 = (8,888,888,889)-4 = 307K = 34C Had I not allowed for emissivity (i.e. regarded the surface to be a blackbody), the sunlit hemisphere would have a mean surface temperature of only 303K or just 30C. Postma is therefore out by at least 15K. If we then allow for atmospheric absorption of 22.9% of the TOA solar flux, we would have to subtract another 313 W/m2 from the 958 W/m2 to give 644 W/m2 and divide that by 2 to give a surface flux of just 322 W/m2. Plugging that figure into the above equation gives a temperature just 278K or 5C. Since Earth rotates too fast for equilibrium to be reached, the sunlit hemisphere would be even less than 5C, over 10C below the observed mean for the entire half-dark globe! It is much warmer than that, of course, thanks to downwelling IR from an atmosphere that is warmed from above and below. 8 1.2. The lapse and cloud-height forcing On page 7, Postma discusses the lapse rate (I), the flux-weighted mean radiating altitude (H) and the formula of Hansen et al (1981)7 relating IH to the observed surface temperature (Ts = 288K) and effective blackbody temperature (Te = 255K): Ts ~ Te + IH Thus IH = 288K 255K = 33K He then states: Unfortunately, Hansen (et al.) (ibid) do not state the actual mechanism by which IH arises, nor were any references made for such, but it is apparent they considered it (IH ) to be representative of the GHE itself. The lapse rate I (both dry and wet values of it, as we will see) can be derived from first principles. Postma correctly shows how the dry adiabatic lapse rate (Id) can be thus derived, ultimately from gravity (g = 9.808 m/s2) divided by the thermal capacity or specific heat (Cp) of air (1.005 kJ/kg/K), so that: Id = 9.76 K/km. (Postma uses 9.8 and 1.006 to derive Id = 9.74 K/km) Postma calls this simply the lapse rate rather than the theoretical dry adiabatic lapse rate, the change in temperature as a parcel of dry air moves up or down while exchanging no energy with its surroundings. It is not to be confused with the actual environmental lapse rate which is not adiabatic and varies across space and time. As per Postma on Hansen et al, it is apparent he considers it (IH) to be representative of gravity and specific heat; but how does that explain the fact that the lapse rate drops to zero at the tropopause? Gravity doesnt suddenly drop to zero, nor does the specific heat of air soar to infinity. The simple reason is that warming from above equals that from below at the tropopause; and this has much to do with IR-absorbing/emitting gases. A lapse rate is entirely dependent on a heat pump at the base of the air column. Remove that and the lapse rate drops to zero and then inverts, as it does over Polar Regions during winter and elsewhere during cold winter nights. Such inversions would be far more frequent without the atmospheric GHGs that reduce overnight cooling and diurnal variations in surface temperature. Whereas the moist adiabatic lapse rate is ~5.5K/km, Postma confuses this with the average environmental lapse rate (~6.5K/km): The wet, or more commonly known as the normal or globally averaged lapse rate, can be derived from the result of Equation (3) and the value of the average atmospheric water vapour concentration at the surface of the Earth. Water vapour concentration at the surface of the Earth varies between 1% and 4% by volume [11], so an average value for the volume concentration can be taken as 2.5%. (p. 8) Wikipedia, his source [11], states that water vapour is typically 1%-4% at surface. Its a long bow to say that the average value is therefore 2.5%. Postma continues: For an ideal gas, the molar concentration is the same as the volume concentration . . . Apart from the fact that water vapour is not an ideal gas, molar concentration (Xm) is not the same as volume concentration (Xv) but rather proportional to Xv. He then correctly determines that a cubic meter of air at sea level with a water vapour content of 2.5% by volume contains 0.0194kg of water. Wrongly assuming that this uniformly diminishes with altitude to virtually zero at 10 km, Postma says we can linearly interpolate the rate of condensation per meter, as the air parcel rises, at 1.94 x 10-6 kg/m. (ibid) But the height of the tropopause varies 9 across time and space, from 18km, the lapse rate is not constant and water vapour condenses out nonlinearly as cloud layers, as explained in Wikipedia: An unsaturated parcel of air of given temperature, altitude and moisture content below that of the corresponding dewpoint cools at the dry adiabatic lapse rate as altitude increases until the dewpoint line for the given moisture content is intersected. As the water vapor then starts condensing the air parcel subsequently cools at the slower moist adiabatic lapse rate if the altitude increases further. Postma then derives the wet rate of 6.24 K/km, which is 4% less than the observed mean but nevertheless deemed satisfactory given the average values used. (p. 9) He then works in reverse starting from the observed environmental lapse rate to derive the mean water vapour content at the surface: 2.29%, which is 8.4% less than his original 2.5%. Using the lapse rate figure of 6.5K/km and the mean radiative layer height (derived from this lapse rate and the observed values for Ts and Te ), Postma derives IH from first principles without involving a GHE: If we combine the above result of the natural temperature distribution (lapse rate) of the atmosphere due to gravity, thermal heat capacity, and water vapor condensation, with the fact that the average radiating layer and temperature is found at ~5 km in altitude, we find that IH ~ 33 K (ibid) You can always get the answer you want when you start with it! Only adiabatic lapse rates can be derived from first principles; adiabatic appearing nowhere in Postmas paper. It requires an atmosphere in hydrostatic equilibrium undisrupted by wind turbulence, and no energy gain or loss by IR absorption or emission. Postma ignores such non-adiabatic transfers of energy. This reduces the lapse rate in the lower troposphere and increases it at altitude, thus counteracting the latent heat effect there; and so GHGs help to even out the lapse rate. In this formulation, the GHE doesnt specifically have anything to do with actual heating of GHGs or heating caused by backradiation from GHGs per se, but is only about setting the radiative scale height H. However, with increasing global surface temperature and increasing CO2 concentration (not necessarily causally related a priori), no increase in the temperature scale height of the atmosphere has actually been observed [13], thus putting into question the GHE postulate itself, and the source of the warming. (ibid) His citation [13] is to an article on The Missing Hotspot by David Evans, who explains the greenhouse theory, accepts a GHE and admits a faint or absent hotspot in his conclusion: Between a half and two thirds of the temperature increases predicted by the IPCC are due to their assumed theoretical water vapor feedback, which is also responsible for the hotspot. Reducing the water vapor feedback in the climate models in line with the faint or absent hotspot in the observed warming pattern, while leaving the rest of their climate model unchanged, cuts the temperature increases projected by the IPCC by more than half. From four sources of radiosonde data, Douglass et al (2007)8 likewise found that the tropical mid-tropospheric warming trend during the satellite era (1979-2004) was modest (~0.1C/decade) and less than a third of the mean projected by 22 CGCM models. They did find a greater warming trend at 8-10km than at 3-6km, but it was greater still at the surface (Fig. 4). 10 Figure 4: Temperature trends (C/decade) over the period 1979-2004 against pressure (altitude) for four radiosonde results (HadAT2, IGRA, RATPAC & RAOBCORE = Observations) compared to the average of 22 model predictions (solid red line) 2SE (lighter red lines) and two satellite MSU data sets (RSS and UAH): the mean heights for T2lt and T2 being 2.5km and 6.1km respectively. The surface temperature trend (Sfc) comes from HadCRUT, GISS and GHCN. Source: Douglass et al, 2007 There are several explanations for the surface warming of ~0.15C/decade: either that it was primarily solar or that the surface temperature record was inappropriately adjusted for urban heat and homogeneity, as argued by Lindzen 9 and others,10 or perhaps both. Using data from NCAR, NCEP and the European Centre for Medium-Range Weather Forecasts, Santer et al (2003) 11 inferred that the tropopause had risen several hundred metres since 1979; but this was contested by Pielke and Chase (2004).12 The evidence for greenhouse warming last century is neither strong nor entirely absent. Spencer and Braswell (2010) 13 concluded from their study of clouds and feedbacks: It is clear that the accurate diagnosis of shortterm feedbacks (let alone longterm climate sensitivity) from observations of natural fluctuations in the climate system is far from a solved problem. Postma quotes Davies and Molloy (2012)14: the decadal change in radiative forcing from CO2 is equal in magnitude (~0.28 W/m2) to a change in effective cloud height of +19m *17+ . . . [and postulates] If the cited cloud-height-forcing were linear, which we might expect from Equations (1) to (3), then as an approximation an effective cloud height of only 2.24 km would correspond to the 33K forcing of the GHE, without needing to refer to any additional backradiative heating mechanism. (p. 9-10) The +19m is less than the variability described by Davies and Molloy: The linear trend is 44 22 m/decade and the interannual annual difference is 31 11 m between the first and last years of the decade. The annual mean height is measured with a sampling error of 8 m, which is less than the observed interannual fluctuation in global cloud height for most years. Moreover, clouds have different cooling/heating effects in different parts of the atmosphere at different times of the day in different parts of the world.15 Again, the picture is far more complex than presented by Postma. 11 2. Development of the GHE via Conservation of Energy Heat Flow Mechanics 2.1. The conservation of heat energy ordinary differential equation Pages 11-18 are taken up with heat-flow equations and time-lags in response rates at various depths of Earths surface at two time constant tau (t) values (0.05x105 and 4x105): The t values therein would correspond, if modeling (sic) a sandy surface and soil of specific heat Cp = 800 J/kg/K [23], to masses of 6.25kg and 500kg, which equate to square-meter soil columns of approximately 4mm and 31cm deep, given a soil density of 1600 kg/m3 *23+. (p. 14) The various equations are nicely solved and graphed using Matlab. This is straightforward and uncontentious. My only quibble would be the use of an emissivity of 0.7 in the Matlab script (Appendix D, p. 61) to produce Figure 4 (p. 18). Postma bases this on Kirchhoffs Law, but the terrestrial emission spectrum is quite different from the solar absorption spectrum; and his albedo of 0.3 used in the Matlab script does not pertain to the surface either. 2.3. The conservation of heat-energy ODE and the greenhouse effect Page 19: We note that, in typical treatments of the mechanism and physics of the GHE, greenhouse warming is proportional to the surface output flux because some fraction of that flux is absorbed into the atmosphere and then emitted and/or scattered back to the surface, which thus causes further heating. This is the so-called back-radiation formulation (see Appendix H for a sample list of quotation references adhering to the back-radiation mechanism of the GHE), and it is functionally distinct from the formulation discussed earlier in this report. So if from Equation (11) C(t)= eoT4, where is the fraction of output flux which is kept from exiting the system and/or returned to the surface thus causing the greenhouse effect, we can just write t

= F in + C (t) (1 )eoT4 (W/ m2) (15) and where C(t) is no longer a term which can represent the greenhouse effect, but is kept for generality. In this formulation, the greenhouse effect as the gamma term has the same effect as emissivity. However, the bulk of the atmosphere is actually very stable in temperature, so the (1 ) term could be removed and another constant term such as G0 could be added to represent greenhouse effect heating. . . . So let us just write t

= F in + GO (1 )eoT4 (W/ m2) (16) and then we can explore the effects of using either G0 or in a numerical solution to get an idea of how the greenhouse effect affects the heat flow balance. Instead of removing (1 ), as he said he could, Postma removed C(t) and replaced that with G0. There thus appears to be a contradiction between his text and his revised formula [16]. He had defined C(t) on page 13: C(t) is literally a climate term which could be either positive or negative (adding heat or taking heat away) in total, or composed of several unique contributions depending on if there is an additional heat source such as the greenhouse effect, or chemical and geologic sources etc., or an active cooling mechanism such as that caused by wind. So, in removing C(t) he removed any adjustment for heat loss by thermals and evaporation, and replaced it with a second additive greenhouse variable in his formula [16]. Little wonder then that Postma obtained such strong temperature responses when he used the KT97 value of 324 W/m2 for 12 G0, illustrated in his Figure 5; and the Jacob (1999) value of 0.77 for in his Figure 6; both shown on page 21 and discussed on page 22 (and reproduced below). If you factor in the KT97 backradiation of 324 W/m2, you also need to factor in the KT97 energy losses for thermals (24 W/m2) and evaporation (78 W/m2). Indeed, you need to subtract multiples of the combined global mean (~102 W/m2) for peak evaporation and thermals at or shortly after zenith insolation, whereas the GHE input remains constant. Figure 5: Temperature responses with and without G0 term for two values of tau. The value for G0 is explained in the text. Figure 6: Temperature responses with and without gamma term for two values of tau. The value for is explained in the text. Note that Postmas temperature response to =0.77 is even greater than that to G0=324 W/m2. Had he plugged both values (for G0 and ) simultaneously into his formula [16], which it permits, he might have produced a Venus-like temperature! On page 28, he links his fictitious formula [16] to papers by Smith [2], Kiehl and Trenberth [25] and others. But you wont find any such formula there. 13 3. Discussion of Data and Collection 3.1. Raw data Postma describes the half-hourly monitoring of air and ground temperature and insolation over two days (21-22 June, 2012) up by Carl Brehmer at Chino Valley in Arizona at latitude 34.8N and altitude 4,701ft (1,433m). To monitor insolation, he used an Apogee model MP-200 pyranometer, which measures wavelengths 280-2800nm with an error of 3000nm). The air temperature and humidity were monitored using an EasyLog model EL-USB-2 and the ground temperature with a thermocouple and EasyLog model EL-USB-1. Whereas Postma says: Day-time-high air temperatures are typically observed approximately 3 hours after the solar noon, (p. 15) Brehmers peak temperature occurred at 1.30pm on both days. The raw data is tabulated in Postmas Appendix F (pp. 64-66) and plotted in his Figure 7, reproduced below: Figure 7: Plot of raw measurement data of insolation and ground and air temperatures. Data analysis is found in a later section. 3.2. Preliminary data analysis The measured maximum insolations from day 1 and 2 were 1060 W/m2 and 1052 W/m2, respectively, while the calculated TOA flux was 1291 W/m2 for both days. . . . Averaging the maximum flux values results in an extinction of . . . 0.182 or 18.2%. The calculated TOA flux was then linearly scaled down to reflect this value, and the comparison to the measured insolation is seen in Figure 8, below. (p. 24) 14 Figure 8: Plot of calculated & measured insolation curves, showing extinction. Carl Brehmer measured the surface reflectivity over 12 hours on June 13, 2012, by turning the pyranometer upside-down and registering the value of reflected short-wave radiation; the results can be found in Appendix G, and are plotted in Figure 9 and Figure 10, and the measurements have an average value of o ~ 0.26 . (p. 26) The albedo actually varied from about 3.0 at sunrise and sunset (0) to 2.2 at midday (80). I have no problems with Postmas presentation of Brehmers study thus far. 3.3. Comparison of the postulate of the greenhouse effect to empirical data Our surface thermocouple was attached directly to the ground surface and measured the rise and fall in its temperature throughout the day; if the greenhouse effect is present and the sky clear so that there are no confounding factors from clouds etc. - all you have is the pure insolation and straight greenhouse effect - then the temperature generated upon the surface has to rise above that provided by solar insolation alone, otherwise we lose the basis for the greenhouse effect postulate in the first place. In the next section we discuss an even easier way to test for this, but see Figure 11 below. (p. 28, emphasis mine) Figure 11: No greenhouse effect is observed in empirical data. 15 In Figure 11, we have taken the measured solar insolation values and converted them to their temperature-forcing value (factored for albedo), and plotted that against the ground temperature and air temperature. As can be seen, the ground temperature does not exceed the temperature of the solar insolation. This is impossible given the conditions of Equation (16) with either formulation of the greenhouse effect heating term . . . (p. 29) I cant fault the maths and admit that Postmas argument looks impressive at first glance; but he forgets what he said on pages 15 and 16 when claiming there are no confounding factors from clouds etc. - all you have is the pure insolation and straight greenhouse effect. On page 15, he states: The natural cooling effects of the air due to convection and wind, which is driven by the temperature generated upon the ground . . . and that temperature on the ground on Day 1 went to a scorching 345K (72C), which was 33.5K warmer than the air 1.5m above it, and 31.5K warmer on Day 2. Thermals (conduction and convection) would have had a major cooling effect on that ground. I suspect that the slightly lower temperatures (for both air and ground) on Day 2 related to increased wind and conductive cooling, but the wind speed was unfortunately not measured; nor were any measures taken to limit wind or convective cooling. Postma rediscovers this air-conduction on page 48, where he approvingly quotes Doug Cotton: However, in the case of the surface / atmosphere interface, at least 70% of heat transfer from the surface to the atmosphere is non-radiative transfer. And on page 49, Postma states: The atmosphere is heated . . . mostly by contact with the ground surface . . . GHE-deniers extol non-radiative heat loss when it suits, but quickly and conveniently forget about it when it doesnt! With a thermal conductivity for air of 0.024 W/m.K, we would need to know the air temperature much closer than 1.5m above the ground to calculate the conductive heat loss from a surface at 345K. Using the KT97 value of 24 W/m2 for thermals averaged over the globe, zenith insolation would be expected to produce four times that, and even more with a ground temperature of 72C. So there could be well over 100 W/m2 of GHE, neutralised by conduction / convection, right there in Brehmers data. Moreover, Postma ignores conduction to subsoil. On page 16, he states: Solar forcing acts directly only on the top few millimeters of surface soil itself . . . and this is where the incoming short wave radiant energy performs work and raises the temperature. This heat energy will then conduct its way down into the subsurface until it merges with the geothermal temperature at a depth of somewhere around, say, 5 to 10 meters and temperature of approximately 5C to 10C. But he apparently forgot about this when interpreting his Figure 11. On page 30, he reports Carl Brehmer checking the soil temperature on 28 August (after several months of summer) and finding it to be 25C (298K) at a depth of 84cm, with a diurnal temperature range of just 0.11C. From his Figure 4 (which has aforementioned problems), it is likely that the temperature at this depth on 21-22 June was several degrees cooler (i.e. 22-23C). So the temperature difference from the surface to 84cm on 21 June could have been ~49K. We dont know enough about the nature, density and moisture content of Brehmers soil to accurately calculate conductive heat loss; but if we accept a thermal conductivity of ~0.9W/m.K for dry sandy loam,16 the conductive loss would be:

= ~53 W/m2 So we now have at least 150 W/m2 of GHE, neutralised by conduction to air and soil, and probably a great deal more. Furthermore, the peak surface temperature was 45-50C warmer than soil 84cm 16 below, whereas the overnight surface minimum was just 5-8C cooler than the subsoil at 84cm. The peak surface cooling temperature gradient was thus 6-10 times the peak surface warming gradient from below, thus suggesting additional energy input from above. The ground temperature on Day 1 was above the albedo-corrected insolation temperature at all times other than at the very peak. The increasing ground temperature in the early morning could only be coming from above; and although the air temperature warmed faster than ground temperature soon after sunrise on both days, this could not convectively warm the ground beneath it (as Postma aptly points out on page 34). Rather, as the sun-warmed air stopped cooling the surface, atmospheric radiation reinforced the weak insolation and so the ground temperature rose well ahead of the insolation temperature, as shown in Figure 11. When the ground temperature peaked at 72C, solar radiation received exactly equalled radiation emitted, and therefore heat lost by conduction (above and below) had to exactly equal thermal energy gained from absorbed atmospheric radiation. Brehmers data demonstrates very nicely that, without any atmospheric input of energy there is ipso facto no spare energy for conduction (up or down) and therefore no heat storage. You cant have one without the other. If there was no atmospheric input, there could be no conductive loss, even at peak insolation. GHE-deniers thus have to deny (or conveniently ignore) conduction when interpreting Figure 11. Postma also ignored the effect of humidity and altitude on the greenhouse effect at Chino Valley in Arizona. Brehmer recorded a relative humidity of just 2.5% at peak insolation when air temperature was 311K. The water vapour content at this altitude and temperature was therefore only about 0.17% by volume. This is just 6.8% of the global average of 0.0194kg/m3 calculated by Postma; and since the height of the troposphere is 15% less at 1433m elevation, the total tropospheric water vapour (the dominant GHG) above Brehmers monitoring station was barely 6% of Postmas global average. The GHE at Chino Valley in June would thus be significantly less than the global average, but still sufficient to clearly show itself in Brehmers data. Rather than disproving the GHE, therefore, Brehmers observations very nicely demonstrate it. 3.4. The back-radiation/glass greenhouse justification for the GHE I have no problem with Postmas description of how greenhouses actually work or his criticism of simplistic explanations of the GHE (in Appendix H), or even with his assertion on page 32: If back-radiation augments the warming that sunlight provides, as alleged in the references and quotations in Appendix H and by the heat-flow equation developed earlier in this report, then the atmospheric GHE should be able to generate higher temperature than real-time insolation can provide, even at its maximum. To this author's knowledge, however, this has never been demonstrated for a greenhouse, let alone the actual atmosphere. In his heat-flow equations developed earlier, however, Postma did not correct for the absorption of solar IR by glass or GHGs. Because of the reduced transmittance of solar IR, daytime experiments with glass have not confirmed any GHE; but I am unaware of any night-time studies of cooling rates. I therefore propose the following experiment: 17 Overnight Greenhouse Experiment Each of four identical white Styrofoam boxes (Fig. 12) would be filled as follows: - Bottom 1/3 with dry river-sand (equal quantities for thermal mass, and a thermocouple placed above it at the centre) - Middle 1/3 with dry air (and covered with a thin IR-transparent film) - Top 1/3 with experimental Gas (containing a sealed water reservoir in one corner, a thermocouple suspended as shown and covered with the same IR-transparent film) Figure 12: Depiction of control and experimental boxes for 3-day GHE experiment All boxes would slope slightly towards the corner with the water reservoir so that condensation would run into the open reservoir in the water vapour box (# 3 below). The Gas in the upper chamber of each box would be: 1. Control Box: - Ambient air of low humidity 2. Pure CO2: introduced from a gas cylinder through a valve in the side of the box and vented at the top until more than full and the valve closed 3. Water vapour:- saturated air and OPEN water reservoir 4. Greenhouse:- Ambient air of same low humidity as control box with IR-absorbing glass on top of IR-transparent film The boxes would be simultaneously placed close to each other, but separated, in a uniformly sun-exposed area for three days (72 hours) during the Australian summer, during which temperatures would be simultaneously recorded at 2-hourly intervals from digital thermometers connected to all 8 thermocouples and plotted against time. The fine details of this concept need clarification and elaboration. Now, back to Postmas paper: To test for a GHE at peak insolation, Postma proposes a simple experiment using black paper (Bristol board) with a thermocouple on top of it. He suggests putting it on top of a stack of sheets to help insulate against the surface contact, thus acknowledging that this paper has poor thermal conductivity. So the thermocouple would be heated more by direct sunlight than by the paper, and his discussed absorptivity/emissivity of the paper is almost irrelevant. He does at least advise a wind-break to limit conductive loss. Pity Brehmer didnt do this. 18 Postma concludes section three by likening radiation to conduction and by misrepresenting adherents of the GHE: Now, it is interesting to note that physics has never considered a back-heating term from back-conduction, in that the heat from the atmosphere, being of a cooler temperature but having been gained from the surface originally, is never thought to sensibly return to the surface again and thus further increase its temperature, or alternatively, to cause an increase in temperature due to the conductive resistance from the atmosphere. This is only a scheme that adherents of the GHE seem to propose for radiation when they suggest that back-radiative heating, or alternatively sometimes called back-radiative resistance, does cause such a temperature increase, with their necessary justification being postulated that radiation doesnt need to follow the Laws of Thermodynamics in the same way we expect of sensible transfer. This is of course rather doubtful. (p. 34) That energy transfer by radiation is fundamentally different from sensible heat transfer by conduction is very basic physics. Sound proponents of the GHE clearly differentiate the two and never say that backradiation on its own heats Earths surface, or that it contravenes any Laws of Thermodynamics. Indeed, it is the GHE-deniers who ignore the first law of thermodynamics when asserting that the electromagnetic energy in backradiation has no thermal effect on Earths surface, or else deny Kirchhoffs Law by claiming that those wavelengths are not absorbed. This is a case of the pot calling the kettle black. 19 4. The Sun and Global Energy 4.1. The sun heats the Earth? Is it possible that the Sun can heat the Earth all by itself, or does the atmosphere provide twice as much heating energy as the Sun provides as per the K&T Global Energy Budget *25+ as supported by the IPCC and believed by all supporters of the GHE? (p. 35) This (twice as much) is not quite true for the KT97 budget, but it is for the revised energy budget of Trenberth et al 2009. I have discussed problems with these energy budgets in my critique of Slaying the Sky Dragon. What Postma overlooks is that the energy in downwelling atmospheric radiation is derived not only from terrestrial IR radiation, but also from absorbed solar radiation plus convected sensible and latent heat of evaporation/condensation. These processes cool Earths surface by day and retard its cooling by night. Postma spends the next five pages or so calculating the prodigious quantities of sensible and latent heat in the oceans and atmosphere, concluding: The latent heat component being on the order of half of the total energy for water at 13C, means that there will be a significant barrier to cooling below 0C as the current circulates through the poles, keeping these regions much warmer than they would otherwise be. This of course will skew-high the characterization of the average global surface temperature and thus provide an interpreted appearance of a GHE when there actually is none. (p. 39) He doesnt do the maths, however, to show how the heat got there or stays there without any assistance from a GHE. As we saw earlier, the global mean temperature would be only 5C without the GHE. Postma merely postulates sola solar and presents no evidence other than his rudimentary model (on p. 43). Of course the sun can heat the sunlit surface all by itself, but not enough for heat storage, and it is powerless at night. Brehmers data demonstrates very nicely that heat storage is impossible without a GHE. Of course the atmosphere doesnt generate heat (except for latent heat), but it slows the radiative losses from Earths surface via clouds reflecting IR and via GHGs absorbing and re-radiating some of it back to the surface. It thus helps to preserve the heat generated by insolation in much the same way as a thermos keeps your coffee warm. 20 5. Conclusion 5.1. The fraud of simple-minded mathematics and sense-perception This is essentially a reiteration of earlier arguments together with some sophistry to dance around radiation, conduction and the first law of thermodynamics. Whereas in radiation, electromagnetic (EM) energy is transmitted in both directions between two separated sources, in conduction, thermal energy flows one way as heat between two contacting bodies or regions with different temperatures. Whereas there is a net radiative transfer of EM energy from the warmer radiating entity to the cooler one, Postma states: The two-way net transfer postulate simply cannot work because it leads to the possibility that radiation from a colder source can warm up a warmer object. (p. 47) You dont reject sound physics simply because some people misinterpret it. He then puts the Claes Johnson twist on the same concept: Johnson actually . . . explains that EM waves/photons are two-way, but the heat transfer mediated by EM waves/photons is one-way. (ibid) In other words, there is indeed a two-way net transfer of EM energy with a net gain by the cooler surface and net loss by the warmer one. Postma then quotes Doug Cotton before presenting his own argument on atmospheric radiation: We cannot distinguish certain parcels of energy for other equal parcels of energy exchanged in the same location, as it is equivalent to no change having occurred at all. The only thing we can detect is that when radiant energy of sufficient power is absorbed, it will induce an increase in temperature until equilibrium is achieved. We know that the area of the warmer Plank curve above that of the cooler curve must be involved and be responsible for the heat transfer and temperature increase, but the mutually corresponding areas of the Plank curves for the two bodys emissions either may, or may not, be exchanged and have the same effect which is no effect. The cool portion of the radiation may or may not travel between the bodies and be exchanged, and it really doesnt matter which option occurs because they are indistinguishable from each other. (p. 49, emphasis mine) Well, it matters a great deal if one of the bodies is radiatively NOT THERE at all. Outer space is not cold, but neither is it warm. It supplies almost no background radiation and provides no barrier at all to radiative cooling. Without IR-emitting gases in the atmosphere, the surface would receive no cool portion of its radiation spectrum, all terrestrial radiation would be lost to space and the surface would therefore cool much faster, especially at night. Whereas the solar spectrum is quite different from Earths, with very little IR overlap, because of the vastly different temperatures, there is relatively very little difference between Earths surface and its atmosphere. According to Kirchhoffs Law, therefore, the surface will absorb all atmospheric IR it wont reflect any of it. And the first law of thermodynamics demands that that EM energy does not simply vanish when absorbed, but is converted to thermal energy. Of course that cant warm a surface that is losing energy faster than it is receiving it, but it sure reduces the net loss and thus the rate of cooling. The outer layer of a thermos cant warm your coffee, but reflects almost the same EM energy as it receives. Does that mean it has no effect or that it really doesnt matter? Take it away, then, and see how long your coffee stays hot! If you dont believe that background radiation from cooler sources makes any difference, do the following simple experiment. Hold one hand about 5cm above a kitchen bench at room temperature (about 298K or ~10C below that of your hand) and the other hand about 5cm above a block of ice (273K) a little larger than your hand and placed on a corner of the table so that the cooled air around it can easily descend. Your hand above the ice will soon feel cooler because it 21 receives less background radiation than the hand above the bench. If you now replace the ice with a bowl of liquid nitrogen (at 77K) your hand will soon feel even colder because it is receiving even less background radiation. If you want to be objective, attach a thermocouple to your hand and record the temperature changes. Regardless of its intensity or wavelength, background radiation always matters, simply because it is there. We are so used to it that we only become aware of it when it isnt there. If you could expose your naked body to space, you would lose about 500 W/m2 (or ~1,000W for the average man) and cool very rapidly. Even an insulating space suit has to be warmed. Without GHGs, Earths naked surface would radiate 390 W/m2 directly to space and likewise cool more rapidly, especially at night. Postma nevertheless points out that: Cooling at the surface is enhanced by the atmosphere during both day and night, rather than retarded. The top 10 meters or so of a square meter column of soil holds more heat, and holds it at a higher temperature, than the entire 10,000 kg of atmosphere going from the surface to outer space. (p. 50) Yes, the atmosphere does conductively cool the ground by day and to a much lesser extent at night. As Brehmers data shows, the temperature difference at night is very small and often reverses for a short time after sunrise. But radiative energy transfer is not conductive; and besides, atmospheric radiation does not warm the surface at night, but merely retards its radiative cooling. As scientists, we need to be careful in distinguishing radiation from conduction, EM energy transmission from heat flow and warming from reduced cooling. These are often confused on both sides of the GHE-debate. Once we get the terminology right and consistently clarify our usage of it, we can begin meaningful discussions. 5.2. A Note on the Human Mind This is more about philosophy than science. In matters of science, we need to let the evidence and the reasoning shape the philosophy, not the reverse. We need to first get the science right. This is the only point in the entire critique (apart from my introduction) to which Postma responded: This represents the typically illiterate state of mind of most so-called scientists today. Where does science come from? Science comes from philosophy! This anti-intellectual, a-logical, materialist edifice of philosophically illiterate post-modern science is precisely why, presumably with a perfectly straight face and totally unawares, that so-called scientists can state that the atmospheric GHE causes heating but is impossible to observe because the atmosphere is such a strong coolant(!). Yes, the flat-earth notion came from philosophy, but science turned that on its head. Notions of the cause of melancholia and blood-letting practices also came from the philosophy about four humours, but science has thankfully changed our philosophy. The question is whether Postma will permit science to shape his philosophy. I will let the reader decide whether his last sentence is an accurate portrayal of my critique of his paper, or a rhetorical sophism to hide his fundamental failure to factor conduction and convection into his formula 16 and Carl Brehmers experiment. I will also let the reader decide whether Postma has demonstrated the absence of a GHE or otherwise. Postscript 2.1.13 Empirical evidence for a greenhouse effect is provided by Carl Brehmer and Joe Postma, in a discussion paper purporting to show the Absence of a Measureable Greenhouse Effect, found at: http://principia-scientific.org/publications/Absence_Measureable_Greenhouse_Effect.pdf 22 Carl Brehmer monitored insolation, ground and air temperature every half-hour in June 2012 at Chino Valley in Arizona, and Joe plotted his data for June 21 and 22 (Days 1 and 2 resp.) in figure 11. This shows that the ground temperature exceeded the insolation temperature (corrected for albedo) for the whole of Day 1, except for a brief period at peak insolation, when they both reached 345K. Joe interpreted this as evidence that there was no additional warming from atmospheric radiation or GHE. But he completely overlooked conduction (fancy that!) both to the atmosphere and to the subsoil. Evaporative cooling would have been negligible in that arid location. From the limited data available, I estimated conductive losses at the surface to exceed 150W/m2 at 345K. The only possible source of extra energy for this conductive loss (additional to the radiative loss calculated from the S-B equation at 345K) is atmospheric radiation. This is less than half Trenberths 333W/m2 (2009 Energy Budget), but still very significant. It would be lower than the average given the altitude (4,701 ft) and very dry air over Brehmers monitoring station. Rather than acknowledging his mistake, Joe Postma called my critique a joke, and stated: Youre not offering up mistakes, youre offering obfuscations. All that exists anymore are semantic word arguments for what people imagine and want it to do. Wes, conduction is not an active cooling force like you find from a refrigeration pump cycle. Conduction is simply the spreading out of heat energy gained from some source, it doesnt actively cause cooling. . . . Youre saying atmospheric radiation, from a colder atmosphere, conducted into the sub-surface. First, radiation doesnt conduct . . Heat flows from hot to cool automatically and this doesnt require sustained input. . . . Conduction is not an active cooling process. In this case conduction is a natural flow from hot to cool given the solar input which heats the surface. Conduction here is not the introduction of cold material to a warmer location. Long-wave from the atmosphere can in no way, shape, or form, induce the same or similar heating action as the short-wave solar input. I will let others judge who is obfuscating and using semantics. Joe would have us believe that passive conduction doesnt cool the surface or require sustained energy input! Anyone who looks at Joes figure 11 will see that the surface is warmer than it should be (from insolation alone) for almost the entire Day 1, especially as the sun sinks and the (extra) stored thermal energy in the subsoil returns to the surface. Had Joe thought about this as a scientist, instead of as a sophist, he might have considered surface emissivity. With an emissivity of less than 1, the ground would lose less radiation than indicated by its temperature, and so there might be some spare energy for conduction, as well as for radiation. 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