Note: This was a poster, and adopted into a blog post by the author, Ned Nikolov, specifically for WUWT. My thanks to him for the extra effort in converting the poster to a more blog friendly format. – Anthony
Expanding the Concept of Atmospheric Greenhouse Effect Using Thermodynamic Principles: Implications for Predicting Future Climate Change
Ned Nikolov, Ph.D. & Karl Zeller, Ph.D.
USFS Rocky Mountain Research Station, Fort Collins CO, USA
Emails: ntconsulting@comcast.net kzeller@colostate.edu
Poster presented at the Open Science Conference of the World Climate Research Program,
24 October 2011, Denver CO, USA
http://www.wcrp-climate.org/conference2011/posters/C7/C7_Nikolov_M15A.pdf
Abstract
We present results from a new critical review of the atmospheric Greenhouse (GH) concept. Three main problems are identified with the current GH theory. It is demonstrated that thermodynamic principles based on the Gas Law need be invoked to fully explain the Natural Greenhouse Effect. We show via a novel analysis of planetary climates in the solar system that the physical nature of the so-called GH effect is a Pressure-induced Thermal Enhancement (PTE), which is independent of the atmospheric chemical composition. This finding leads to a new and very different paradigm of climate controls. Results from our research are combined with those from other studies to propose a new Unified Theory of Climate, which explains a number of phenomena that the current theory fails to explain. Implications of the new paradigm for predicting future climate trends are briefly discussed.
1. Introduction
Recent studies revealed that Global Climate Models (GCMs) have significantly overestimated the Planet’s warming since 1979 failing to predict the observed halt of global temperature rise over the past 13 years. (e.g. McKitrick et al. 2010). No consensus currently exists as to why the warming trend ceased in 1998 despite a continued increase in atmospheric CO2 concentration. Moreover, the CO2-temperature relationship shows large inconsistencies across time scales. In addition, GCM projections heavily depend on positive feedbacks, while satellite observations indicate that the climate system is likely governed by strong negative feedbacks (Lindzen & Choi 2009; Spencer & Braswell 2010). At the same time, there is a mounting political pressure for Cap-and-Trade legislation and a global carbon tax, while scientists and entrepreneurs propose geo-engineering solutions to cool the Planet that involve large-scale physical manipulation of the upper atmosphere. This unsettling situation calls for a thorough reexamination of the present climate-change paradigm; hence the reason for this study.
2. The Greenhouse Effect: Reexamining the Basics
Figure 1. The Atmospheric Greenhouse Effect as taught at universities around the World (diagram from the website of the Penn State University Department of Meteorology).
According to the current theory, the Greenhouse Effect (GHE) is a radiative phenomenon caused by heat-trapping gases in the atmosphere such as CO2 and water vapor that are assumed to reduce the rate of surface infrared cooling to Space by absorbing the outgoing long-wave (LW) emission and re-radiating part of it back, thus increasing the total energy flux toward the surface. This is thought to boost the Earth’s temperature by 18K – 33K compared to a gray body with no absorbent atmosphere such as the Moon; hence making our Planet habitable. Figure 1 illustrates this concept using a simple two-layer system known as the Idealized Greenhouse Model (IGM). In this popular example, S is the top-of-the atmosphere (TOA) solar irradiance (W m-2), A is the Earth shortwave albedo, Ts is the surface temperature (K), Te is the Earth’s effective emission temperature (K) often equated with the mean temperature of middle troposphere, ϵ is emissivity, and σ is the Stefan-Boltzmann (S-B) constant.
2.1. Main Issues with the Current GHE Concept:
A) Magnitude of the Natural Greenhouse Effect. GHE is often quantified as a difference between the actual mean global surface temperature (Ts = 287.6K) and the planet’s average gray-body (no-atmosphere) temperature (Tgb), i.e. GHE = Ts – Tgb. In the current theory, Tgb is equated with the effective emission temperature (Te) calculated straight from the S-B Law using Eq. (1):
where αp is the planetary albedo of Earth (≈0.3). However, this is conceptually incorrect! Due to Hölder’s inequality between non-linear integrals (Kuptsov 2001), Te is not physically compatible with a measurable true mean temperature of an airless planet. To be correct, Tgb must be computed via proper spherical integration of the planetary temperature field. This means calculating the temperature at every point on the Earth sphere first by taking the 4th root from the S-B relationship and then averaging the resulting temperature field across the planet surface, i.e.
where αgb is the Earth’s albedo without atmosphere (≈0.125), μ is the cosine of incident solar angle at any point, and cs= 13.25e-5 is a small constant ensuring that Tgb = 2.72K (the temperature of deep Space) when So = 0. Equation (2) assumes a spatially constant albedo (αgb), which is a reasonable approximation when trying to estimate an average planetary temperature.
Since in accordance with Hölder’s inequality Tgb ≪ Te (Tgb =154.3K ), GHE becomes much larger than presently estimated.
According to Eq. (2), our atmosphere boosts Earth’s surface temperature not by 18K—33K as currently assumed, but by 133K! This raises the question: Can a handful of trace gases which amount to less than 0.5% of atmospheric mass trap enough radiant heat to cause such a huge thermal enhancement at the surface? Thermodynamics tells us that this not possible.
B) Role of Convection. The conceptual model in Fig. 1 can be mathematically described by the following simultaneous Equations (3),
where νa is the atmospheric fraction of the total shortwave radiation absorption. Figure 2 depicts the solution to Eq. (3) for temperatures over a range of atmospheric emissivities (ϵ) assuming So = 1366 W m-2 and νa =0.326 (Trenberth et al. 2009). An increase in atmospheric emissivity does indeed cause a warming at the surface as stated by the current theory. However, Eq. (3) is physically incomplete, because it does not account for convection, which occurs simultaneously with radiative transfer. Adding a convective term to Eq. (3) (such as a sensible heat flux) yields the system:
where gbH is the aerodynamic conductance to turbulent heat exchange. Equation (4) dramatically alters the solution to Eq. (3) by collapsing the difference between Ts, Ta and Te and virtually erasing the GHE (Fig. 3). This is because convective cooling is many orders of magnitude more efficient that radiative cooling. These results do not change when using multi-layer models. In radiative transfer models, Ts increases with ϵ not as a result of heat trapping by greenhouse gases, but due to the lack of convective cooling, thus requiring a larger thermal gradient to export the necessary amount of heat. Modern GCMs do not solve simultaneously radiative transfer and convection. This decoupling of heat transports is the core reason for the projected surface warming by GCMs in response to rising atmospheric greenhouse-gas concentrations. Hence, the predicted CO2-driven global temperature change is a model artifact!
Figure 2. Solution to the two-layer model in Eq. (3) for Ts and Ta as a function of atmospheric emissivity assuming a non-convective atmosphere. Also shown is the predicted down-welling LW flux(Ld). Note that Ld ≤ 239 W m-2.
Figure 3. Solution to the two-layer model in Eq. (4) for Ts and Ta as a function of atmospheric emissivity assuming a convective atmosphere (gbH = 0.075 m/s). Also shown is the predicted down-welling LW flux (Ld). Note that Ld ≤ 239 W m-2.
Figure 4. According to observations, the Earth-Atmosphere System absorbs on average a net solar flux of 239 W m-2, while the lower troposphere alone emits 343 W m-2 thermal radiation toward the surface.
C) Extra Kinetic Energy in the Troposphere.
Observations show that the lower troposphere emits 44% more radiation toward the surface than the total solar flux absorbed by the entire Earth-Atmosphere System (Pavlakis et al. 2003) (Fig. 4). Radiative transfer alone cannot explain this effect (e.g. Figs. 2 & 3) given the negligible heat storage capacity of air, no matter how detailed the model is. Thus, empirical evidence indicates that the lower atmosphere contains more kinetic energy than provided by the Sun. Understanding the origin of this extra energy is a key to the GHE.
3. The Atmospheric Thermal Enhancement
Previous studies have noted that the term Greenhouse Effect is a misnomer when applied to the atmosphere, since real greenhouses retain heat through an entirely different mechanism compared to the free atmosphere, i.e. by physically trapping air mass and restricting convective heat exchange. Hence, we propose a new term instead, Near-surface Atmospheric Thermal Enhancement (ATE) defined as a non-dimensional ratio (NTE) of the planet actual mean surface air temperature (Ts, K) to the average temperature of a Standard Planetary Gray Body (SPGB) with no atmosphere (Tgb, K) receiving the same solar irradiance, i.e. NTE = Ts /Tgb. This new definition emphasizes the essence of GHE, which is the temperature boost at the surface due to the presence of an atmosphere. We employ Eq. (2) to estimate Tgb assuming an albedo αgb = 0.12 and a surface emissivity ϵ = 0.955 for the SPGB based on data for Moon, Mercury, and the Earth surface. Using So = 1362 W m-2 (Kopp & Lean 2011) in Eq. (2) yields Tgb = 154.3K and NTE = 287.6/154.3 = 1.863 for Earth. This prompts the question: What mechanism enables our atmosphere to boost the planet surface temperature some 86% above that of a SPGB? To answer it we turn on to the classical Thermodynamics.
3.1. Climate Implications of the Ideal Gas Law
The average thermodynamic state of a planet’s atmosphere can be accurately described by the Ideal Gas Law (IGL):
PV = nRT (5)
where P is pressure (Pa), V is the gas volume (m3), n is the gas amount (mole), R = 8.314 J K-1 mol-1is the universal gas constant, and T is the gas temperature (K). Equation (5) has three features that are chiefly important to our discussion: a) the product P×V defines the internal kinetic energy of a gas (measured in Jules) that produces its temperature; b) the linear relationship in Eq. (5) guarantees that a mean global temperature can be accurately estimated from planetary averages of surface pressure and air volume (or density). This is in stark contrast to the non-linear relationship between temperature and radiant fluxes (Eq. 1) governed by Hölder’s inequality of integrals; c) on a planetary scale, pressure in the lower troposphere is effectively independent of other variables in Eq. (5) and is only a function of gravity (g), total atmospheric mass (Mat), and the planet surface area (As), i.e. Ps = g Mat/As. Hence, the near-surface atmospheric dynamics can safely be assumed to be governed (over non-geological time scales) by nearly isobaric processes on average, i.e. operating under constant pressure. This isobaric nature of tropospheric thermodynamics implies that the average atmospheric volume varies in a fixed proportion to changes in the mean surface air temperature following the Charles/Gay-Lussac Law, i.e. Ts/V = const. This can be written in terms of the average air density ρ (kg m-3) as
ρTs = const. = Ps M / R (6)
where Ps is the mean surface air pressure (Pa) and M is the molecular mass of air (kg mol-1). Eq. (6) reveals an important characteristic of the average thermodynamic process at the surface, namely that a variation of global pressure due to either increase or decrease of total atmospheric mass will alter both temperature and atmospheric density. What is presently unknown is the differential effect of a global pressure change on each variable. We offer a solution to this in & 3.3. Equations (5) and (6) imply that pressure directly controls the kinetic energy and temperature of the atmosphere. Under equal solar insolation, a higher surface pressure (due to a larger atmospheric mass) would produce a warmer troposphere, while a lower pressure would result in a cooler troposphere. At the limit, a zero pressure (due to the complete absence of an atmosphere) would yield the planet’s gray-body temperature.
The thermal effect of pressure is vividly demonstrated on a cosmic scale by the process of star formation, where gravity-induced rise of gas pressure boosts the temperature of an interstellar cloud to the threshold of nuclear fusion. At a planetary level, the effect is manifest in Chinook winds, where adiabatically heated downslope airflow raises the local temperature by 20C-30C in a matter of hours. This leads to a logical question: Could air pressure be responsible for the observed thermal enhancement at the Earth surface presently known as a ‘Natural Greenhouse Effect’? To answer this we must analyze the relationship between NTEfactor and key atmospheric variables including pressure over a wide range of planetary climates. Fortunately, our solar system offers a suitable spectrum of celestial bodies for such analysis.
3.2. Interplanetary Data Set
We based our selection of celestial bodies for the ATE analysis on three criteria: 1) presence of a solid planetary surface with at least traces of atmosphere; 2) availability of reliable data on surface temperature, total pressure, atmospheric composition etc. preferably from direct measurements; and 3) representation of a wide range of atmospheric masses and compositions. This approach resulted in choosing of four planets – Mercury, Venus, Earth, and Mars, and four natural satellites – Moon of Earth, Europa of Jupiter, Titan of Saturn, and Triton of Neptune. Each celestial body was described by 14 parameters listed in Table 1.
For planets with tangible atmospheres, i.e. Venus, Earth and Mars, the temperatures calculated from IGL agreed rather well with observations. Note that, for extremely low pressures such as on Mercury and Moon, the Gas Law produces Ts ≈ 0.0. The SPGB temperatures for each celestial body were estimated from Eq. (2) using published data on solar irradiance and assuming αgb = 0.12 and ϵ = 0.955. For Mars, global means of surface temperature and air pressure were calculated from remote sensing data retrieved via the method of radio occultation by the Radio Science Team (RST) at Stanford University using observations by the Mars Global Surveyor (MGS) spacecraft from 1999 to 2005. Since the MGS RST analysis has a wide spatial coverage, the new means represent current average conditions on the Red Planet much more accurately than older data based on Viking’s spot observations from 1970s.
Table 1. Planetary data used to analyze the physical nature of the Atmospheric Near-Surface Thermal Enhancement (NTE). Information was gathered from multiple sources using cross-referencing. The bottom three rows of data were estimated in this study using equations discussed in the text.
3.3. Physical Nature of ATE / GHE
Our analysis of interplanetary data in Table 1 found no meaningful relationships between ATE (NTE) and variables such as total absorbed solar radiation by planets or the amount of greenhouse gases in their atmospheres. However, we discovered that NTE was strongly related to total surface pressure through a nearly perfect regression fit via the following nonlinear function:
where Ps is in Pa. Figure 5 displays Eq. (7) graphically. The tight relationship signals a causal effect of pressure on NTE, which is theoretically supported by the IGL (see & 3.1). Also, the Ps–NTE curve in Fig. 5 strikingly resembles the response of the temperature/potential temp. (T/θ) ratio to altitudinal changes of pressure described by the well-known Poisson formula derived from IGL (Fig. 6). Such a similarity in responses suggests that both NTE and θ embody the effect of pressure-controlled adiabatic heating on air, even though the two mechanisms are not identical. This leads to a fundamental conclusion that the ‘Natural Greenhouse Effect’ is in fact a Pressure-induced Thermal Enhancement (PTE) in nature.
NTE should not be confused with an actual energy, however, since it only defines the relative (fractional) increase of a planet’s surface temperature above that of a SPGB. Pressure by itself is not a source of energy! Instead, it enhances (amplifies) the energy supplied by an external source such as the Sun through density-dependent rates of molecular collision. This relative enhancement only manifests as an actual energy in the presence of external heating. Thus, Earth and Titan have similar NTE values, yet their absolute surface temperatures are very different due to vastly dissimilar solar insolation. While pressure (P) controls the magnitude of the enhancement factor, solar heating determines the average atmospheric volume (V), and the product P×V defines the total kinetic energy and temperature of the atmosphere. Therefore, for particular solar insolation, the NTE factor gives rise to extra kinetic energy in the lower atmosphere beyond the amount supplied by the Sun. This additional energy is responsible for keeping the Earth surface 133K warmer than it would be in the absence of atmosphere, and is the source for the observed 44% extra down-welling LW flux in the lower troposphere (see &2.1 C). Hence, the atmosphere does not act as a ‘blanket’ reducing the surface infrared cooling to space as maintained by the current GH theory, but is in and of itself a source of extra energy through pressure. This makes the GH effect a thermodynamic phenomenon, not a radiative one as presently assumed!
Equation (7) allows us to derive a simple yet robust formula for predicting a planet’s mean surface temperature as a function of only two variables – TOA solar irradiance and mean atmospheric surface pressure, i.e.
Figure 5. Atmospheric near-surface Thermal Enhancement (NTE) as a function of mean total surface pressure (Ps) for 8 celestial bodies listed in Table 1. See Eq. (7) for the exact mathematical formula.
Figure 6. Temperature/potential temperature ratio as a function of atmospheric pressure according to the Poisson formula based on the Gas Law (Po = 100 kPa.). Note the striking similarity in shape with the curve in Fig. 5.
where NTE(Ps) is defined by Eq. (7). Equation (8) almost completely explains the variation of Ts among analyzed celestial bodies, thus providing a needed function to parse the effect of a global pressure change on the dependent variables ρ and Tsin Eq. (6). Together Equations (6) and (8) imply that the chemical composition of an atmosphere affects average air density through the molecular mass of air, but has no impact on the mean surface temperature.
4. Implications of the new ATE Concept
The implications of the above findings are numerous and paradigm-altering. These are but a few examples:
Figure 7. Dynamics of global temperature and 12-month forward shifted cloud cover types from satellite observations. Cloud changes precede temperature variations by 6 to 24 months and appear to have been controlling the latter during the past 30 years (Nikolov & Zeller, manuscript).
A) Global surface temperature is independent of the down-welling LW flux known as greenhouse or back radiation, because both quantities derive from the same pool of atmospheric kinetic energy maintained by solar heating and air pressure. Variations in the downward LW flux (caused by an increase of tropospheric emissivity, for example) are completely counterbalanced (offset) by changes in the rate of surface convective cooling, for this is how the system conserves its internal energy.
B) Modifying chemical composition of the atmosphere cannot alter the system’s total kinetic energy, hence the size of ATE (GHE). This is supported by IGL and the fact that planets of vastly different atmospheric composition follow the same Ps–NTE relationship in Fig. 5. The lack of impact by the atmospheric composition on surface temperature is explained via the compensating effect of convective cooling on back-radiation discussed above.
C) Equation (8) suggests that the planet’s albedo is largely a product of climate rather than a driver of it. This is because the bulk of the albedo is a function of the kinetic energy supplied by the Sun and the atmospheric pressure. However, independent small changes in albedo are possible and do occur owning to 1%-3% secular variations in cloud cover, which are most likely driven by solar magnetic activity. These cloud-cover changes cause ±0.7C semi-periodic fluctuations in global temperature on a decadal to centennial time scale as indicated by recent satellite observations (see Fig. 7) and climate reconstructions for the past 10,000 years.
Figure 8. Dynamics of global surface temperature during the Cenozoic Era reconstructed from 18O proxies in marine sediments (Hansen et al. 2008).
Figure 9. Dynamics of mean surface atmospheric pressure during the Cenozoic Era reconstructed from the temperature record in Fig. 8 by inverting Eq. (8).
D) Large climatic shifts evident in the paleo-record such as the 16C directional cooling of the Globe during the past 51 million years (Fig. 8) can now be explained via changes in atmospheric mass and surface pressure caused by geologic variations in Earth’s tectonic activity. Thus, we hypothesize that the observed mega-cooling of Earth since the early Eocene was due to a 53% net loss of atmosphere to Space brought about by a reduction in mantle degasing as a result of a slowdown in continental drifts and ocean floor spreading. Figure 9 depicts reconstructed dynamics of the mean surface pressure for the past 65.5M years based on Eq. (8) and the temperature record in Fig. 8.
5. Unified Theory of Climate
The above findings can help rectify physical inconsistencies in the current GH concept and assist in the development of a Unified Theory of Climate (UTC) based on a deeper and more robust understanding of various climate forcings and the time scales of their operation. Figure 10 outlines a hierarchy of climate forcings as part of a proposed UTC that is consistent with results from our research as well as other studies published over the past 15 years. A proposed key new driver of climate is the variation of total atmospheric mass and surface pressure over geological time scales (i.e. tens of thousands to hundreds of millions of years). According to our new theory, the climate change over the past 100-300 years is due to variations of global cloud albedo that are not related to GHE/ATE. This is principally different from the present GH concept, which attempts to explain climate changes over a broad range of time scales (i.e. from decades to tens of millions of years) with the same forcing attributed to variations in atmospheric CO2 and other heat-absorbing trace gases (e.g. Lacis et al. 2010).
Earth’s climate is currently in one of the warmest periods of the Holocene (past 10K years). It is unlikely that the Planet will become any warmer over the next 100 years, because the cloud cover appears to have reached a minimum for the present levels of solar irradiance and atmospheric pressure, and the solar magnetic activity began declining, which may lead to more clouds and a higher planetary albedo. At this point, only a sizable increase of the total atmospheric mass can bring about a significant and sustained warming. However, human-induced gaseous emissions are extremely unlikely to produce such a mass increase.
Figure 10. Global climate forcings and their time scales of operation according to the hereto proposed Unified Theory of Climate (UTC). Arrows indicate process interactions.
6. References
Kopp, G. and J. L. Lean (2011). A new, lower value of total solar irradiance: Evidence and climate significance, Geophys. Res. Lett., 38, L01706, doi:10.1029/2010GL045777.
Kuptsov, L. P. (2001) Hölder inequality, in Hazewinkel, Michiel, Encyclopedia of Mathematics, Springer, ISBN 978-1556080104.
Lacis, A. A., G. A. Schmidt, D. Rind, and R. A. Ruedy (2010). Atmospheric CO2: Principal control knob governing earth’s temperature. Science 330:356-359.
Lindzen, R. S. and Y.-S. Choi (2009). On the determination of climate feedbacks from ERBE data. Geophys. Res. Lett., 36, L16705, doi:10.1029/2009GL039628.
McKitrick, R. R. et al. (2010). Panel and Multivariate Methods for Tests of Trend Equivalence in Climate Data Series. Atmospheric Science Letters, Vol. 11, Issue 4, pages 270–277.
Nikolov, N and K. F. Zeller (manuscript). Observational evidence for the role of planetary cloud-cover dynamics as the dominant forcing of global temperature changes since 1982.
Pavlakis, K. G., D. Hatzidimitriou, C. Matsoukas, E. Drakakis, N. Hatzianastassiou, and I. Vardavas (2003). Ten-year global distribution of down-welling long-wave radiation. Atmos. Chem. Phys. Discuss., 3, 5099-5137.
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, doi:10.1029/2009JD013371
Trenberth, K.E., J.T. Fasullo, and J. Kiehl (2009). Earth’s global energy budget. BAMS, March:311-323
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UPDATE: This thread is closed – see the newest one “A matter of some Gravity” where the discussion continues.
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Terry Oldberg says:
December 29, 2011 at 3:31 pm
“I believe you’ve misread the article. The authors do not deny the existence of the back radiation. However they assert that, at Earth’s surface, a change in the intensity of the back radiation is matched by a change of the free convective heat transfer. Consequently, changes in the intensity of the back radiation at Earth’s surface lack effects upon the transfer of heat from Earth’s surface.”
The authors fail to realize that radiative energy leaving the earth’s surface is travelling at approximately 186,000 miles per second or for you European cats that’s about 300 million meters per second. Convective updrafts travel even in the most severe convective cells fail to reach 100 meters per second.
Atmospheric greenhouse warming is a result of impedance in the free radiative path from surface to space. Greenhouse gas molecules intercept the radiation and essentially reflect about half of it back at the source. The authors are correct that this may result in greater rate of convection but that is acheived through a greater surface temperature which condutively heats the air to a greater degree making it that much lighter which in turn makes it rise faster. At the same time the higher surface temperature also increases the motive force of radiative transfer and more of it gets squeezed through the impedance of the greenhouse gases just like when you increase the pressure of water more of it will make through a pipe whose diameter remained constant.
This isn’t rocket science but it appears to be more advanced than forestry science.
Well, what do you know? It is calculable. Using the alternate Ideal Gas Law equations I just gave above, they give these results for the three major planets with known atmospheres. Now who says that law does not apply to averaged planets. Well for me, it’s better than current “climate science”.
Used: T = P/ ρ • M/R
Venus Earth Mars -------- -------- -------- P - pressure 9220000 101325 605 N/m2 (Pa) ρ - density 65 1.217 0.015 kg/m3 M - molar mass 0.0434 0.02897 0.04334 kg/mol R - gas constant 8.31451 8.31451 8.31451 J/K/mol -------- -------- -------- T - temperature 740.40 290.09 210.24 KMany of you will recognize these numbers tossed about here over the last few years. If not, see the data in the post or the NASA planet data sheets.
Thanks, Mkelly. How true about work!
This theory is very similar to what Prof. Claes Johnson has said in his “Climate Thermodynamics” http://www.nada.kth.se/~cgjoh/atmothermo.pdf
The lapse rate in the atmosphere is caused by pressure which, as I have been saying for months, affects the rate at which warm air rises and thermal energy converts to potential energy. The lapse rate has absolutely nothing to do with any radiative transfer theory, back radiation or whatever.
To the above we can add the fact that Claes has also proven that any back radiation (or even solar radiation in the lowest IR frequencies) cannot warm the surface if its frequency is below kT/h as explained in my review of Claes Johnson’s “Computational Blackbody Radiation.” (See http://www.climate-change-theory.com/RadiationAbsorption.html )
We can further add the fact that Prof Nahle has published an experiment which confirms that back radiation does no warming http://principia-scientific.org/publications/New_Concise_Experiment_on_Backradiation.pdf
We can also add the fact that temperature records for the Arctic island of Jan Mayer show warmer temperatures in the 1930’s and so no warming whatsoever for over 80 years. (And the Arctic is “meant” to rise up to 8 degrees by 2100.) See my home page: http://climate-change-theory.com
Finally it would appear that back radiation “measurements” are very spurious. Infra-red thermometers measure frequency and convert it to temperature using Wien’s Displacement Law. But to then apply SBL to convert this temperature to radiative flux from a colder layer of atmosphere to a warmer layer is very spurious. Normally, when applying SBL in situations where the surrounds are not at absolute zero, you need to subtract the effective radiation in the opposite direction. The SBL cannot give a positive result for any situation involving a cooler body supposedly radiating to a warmer one. Above all, even if we consider the wave motion of radiation to be two-way, the transfer of thermal energy can only be from warmer to cooler. The temperature information is transferred in the cut-off frequency, just as is used in infra-red cameras and thermometers. Radiation below cut-off will have no effect on the surface. (For more detail see the footnote on my page http://www.climate-change-theory.com/RadiationAbsorption.html )
We are now in the post-greenhouse era, everyone. But, as with many medical discoveries like penicillin, we can expect it to take 20 years before there is general acceptance. But level or slightly declining temperatures should continue until 2028, so that will help. We who think are at the forefront of this breakthrough. Unfortunately, however, you can lead a horse to water but you can’t make him think.
James Sexton says: December 29, 2011 at 8:17 am
A profound reflection – that a hypothesis which has been around for a while, suddenly finds acceptability. And WUWT has earned the right to be the platform for such a tipping-point.
This has been brewing. Tim Channon at Tallbloke’s Talkshop already posted this paper. A couple days earlier, Tim posted his own observations on the extraordinary heat of Jericho which lies some 200+ m. below sea level. Tim’s post shows the straight-line link between temperature and altitude for both Venus and Jupiter.
(This post led me to observe three things so obvious I suspect we simply forget them: the amazingly horizontal line of snow on the hills; the amazingly horizontal lines of most cloud undersides; and the heat of deep underground mines, in contrast to deep undersea temperatures. All direct effects of pressure in the compressible medium of air.)
Huffman is vindicated, as I’ve long felt he deserved. Probably trickles of people have been visiting his pages and thought about his stunning table of correlation of temperatures of Venus and Earth based solely on pressure and distance from the Sun. Plus recent remarks from the inscrutable Paul Vaughan have firmly placed limits on the indomitable Leif.
There are references here and at Talkshop to Levenspiel’s work that is also a brilliant paradigm-shifter and goes hand-in-hand with Nikolov & Zeller: higher past atmospheric pressures were necessary for pteranodon flight and for brontosaurus to raise their heads. Levenspiel, of course, has had multiple refusals of publication.
Innocent question (?) Atmospheric temperature profiles show a minimum (at the mesopause) of some -100°C. How then can anyone claim the Earth’s surface temperature without gases would be a mere 33°C less than 15°C?
The Temp of the atmosphere is essentially determined by the solar energy input, albedo and the ratio of mass of atmosphere to planet.
Levi: Indeed, you are correct that any elementary book on climate science will talk about the basic thermodynamics of the atmosphere, such as the ideal gas law, the condition for hydrostatic equilibrium, and the adiabatic lapse rate. The difference between such books and this post is they correctly put it in context rather than using it to make nonsensical conclusions as Nikolov and Zeller do.
Kevin Kilty says:
December 29, 2011 at 3:49 pm
“Heat transfer from the human body is largely through radiation, convection, and evaporation.”
Not in water. It’s all conductive then and its far more rapid than in air. This is why jumping into water at 60F feels a lot colder than stepping into air at 60F. A LOT colder. You can survive indefinitely in air at 60F with no more than goosebumps but water at 60F will kill you in about 6 hours if you’ve got a life jacket and about 2 hours without one because you’ll become unconscious after 2 hours and drown.
1
Mrss Puller and Kilty,
An appeal to your area of expertise.
Since gravity is a force of acceleration is not its “work” a constant.
Levi, when I first heard of this CO2 warming theory, back in the 1980s, I considered it; I was clever enough to understand the concept, but not knowledgeable enough to have counter-arguments at hand. I did not have a horse in the race, so could afford to change my opinion, which I have.
Many “clever” people also do not understand, but have committed themselves, and their careers, the AGW theory. They do not have the luxury to change opinion.
Well…almost true. The adiabatic lapse rate has nothing to do with what you have mentioned. However, the adiabatic lapse rate is only a stability limit on the actual lapse rate. In an atmosphere heated strongly from below and cooled from above (which is true because of most solar radiation not being absorbed until the surface and also because of the radiative transfer due to greenhouse gases in the atmosphere), the lapse rate will indeed tend to be pegged at the adiabatic lapse rate.
However, the lapse rate alone doesn’t determine the surface temperature, just like the slope of a line doesn’t determine the value of y for any x. You need the temperature at at least one point. In this case, that temperature is the effective blackbody temperature of 255 K and its location in the atmosphere is determined by atmospheric opacity to radiation, i.e., the greenhouse elements of the atmosphere.
No he has not. Claes has replaced a century of physics, involving the entire field of statistical physics, by a hokey axiom that basically asserts the result that he wants. He has given no reason to abandon a century of physics in favor of his ideas. Furthermore, all he has succeeded in doing is re-deriving an equation that still has the greenhouse effect in it. You don’t need so-called “back-radiation” (for which there is abundant experimental evidence) to have the greenhouse effect. You just need the fact that the rate at which a warmer object cools depends on the temperature of a colder object surrounding it as well as its own temperature.
“Innocent question (?) Atmospheric temperature profiles show a minimum (at the mesopause) of some -100°C. How then can anyone claim the Earth’s surface temperature without gases would be a mere 33°C less than 15°C?”
Because the sun doesn’t heat the air in the mesopause. It heats the surface and the surface heats the air. The farther you get from the source of heat the colder it gets whether it’s a pot of coffee farther from a campfire or a volume of air farther from the earth’s surface. Higher than the mesosphere the atmosphere starts absorbing some of the sun’s radiation and temperatures in the thermosphere rise to thousands of degrees. The air temperature the space station is flying through is thousands of degrees. If it weren’t for the fact that it’s almost a vacuum at that point and thus have almost no heat capacity someone could get a nasty burn from it!
Huffman is not vindicated by the way. He’s just some extra cranks to keep him company. I have no idea why Anthony posts stuff like this here because it just makes his blog look like a crank sanctuary.
Levi says: December 29, 2011 at 3:59 pm
Welcome to the real world of Climate Science Levi. There is a lot more stupidity, entrenched stupidity, jeering stupidity, and financially-rewarded stupidity than one would dream possible. IPCC was, from inception, on a mission to assert AGW, subverting true science. Most of us here were once starry-eyed believers in science as practised. And hopefully, here at least, still hold fast this ideal, while not blind to the realities in practice.
Chesty Puller, you have simply thrown dust into the air. The speed of energy transfer – SOL versus convection – has no bearing on steady state. I call Straw Man.
Tim Ball “Wind is the most overlooked variable in climate studies”.
Agreed. Especially so at high latitudes. You demonstrate that point in your work in relation to Canada that I found in “The Year Without a Summer”.
So, I am prompted to put forward a paper that focuses on how and why the wind (and cloud cover) changes in line with geomagnetic activity. See: http://climatechange1.wordpress.com/
And I will be most interested to see further comment from Nikolov and Zeller that expands on their observations on the relationship between cloud cover and temperature and the associated statement from their post, namely:
“However, independent small changes in albedo are possible and do occur owning to 1%-3% secular variations in cloud cover, which are most likely driven by solar magnetic activity. These cloud-cover changes cause ±0.7C semi-periodic fluctuations in global temperature on a decadal to centennial time scale as indicated by recent satellite observations (see Fig. 7) and climate reconstructions for the past 10,000 years.”
But most of all I want to see comment from those who have long maintained that the posited greenhouse effect is real, but exggerated. Come in Monkton, Svalgaard, Eschenback and Spencer. Your support for the notion of a greenhouse effect due to radiative influences needs to be re-assessed.
“Chesty Puller” says:
“Huffman is not vindicated by the way. He’s just some extra cranks to keep him company.”
He makes a good case re: Earth vs Venus. You, OTOH, are apparently a wannabe war hero, and I doubt the real Chesty Puller would condone using his name.
Just a peanut gallery question. How does this all tie in with changes in orbital parameters that have caused the fairly regular periods of glaciation and interglacials over the last 3 million years or so?
I’ll let Puller add whatever he wants, but gravity is a force that we measure through its acceleration on a standard mass. It is more or less constant the world over, yes. And the work done is then related to how much vertical distance one moves a mass and the size of the mass. One kilogram, moved a distance of 1 meter, is about 10J of work. Work=mgh. It is not a constant.
OK, then do the following. There is pressure at altitudes of, say, 100km or 500km above the earth. Please use your modified equation to calculate the temperature up there.
Thermodynamics applies only to systems in equilibrium. No place on earth is ever in equilibrium. You cannot use averages and you do not know them anyway. The Greenhouse theory ignores the outside climate which is mainly controlled by convection and evaporation/condensation, but is currently only partly understoood. It also igniores the crucial difference between day and night.
It is sad that intelligent people can be fooled by the absurd greenhouse model.
Levi says: December 29, 2011 at 3:59 pm
“I am having a hard time believing that all other scientists currently working on the theory of AGW simply forgot to consider adiabatic heating due to atmospheric pressure. It doesn’t seem possible that such an obvious thing could be ignored.”
Apparently, you are not aware that mainstream climate science recognizes no natural processes apart from radiation transfer in the Earth-Sun system. If recognized at all, adiabatic heating due to atmospheric pressure would be treated as an epiphenomenon of radiation transfer.
A simple summation:
i) AGW theory states that the greenhouse effect is caused by gases in the air with a high thermal capacity warming the surface by radiating energy downwards.
ii) This paper describes the greenhouse effect in the way I have always understood it i.e. ALL the molecules near the surface (of whatever thermal capacity) jostle more tightly together under the influence of gravity and share kinetic activity (provoked initially by solar irradiation but actually being a consequence of all energy transfer mechanisms combined) amongst one another until that kinetic energy can escape to space by radiative means albeit slightly delayed by all the jostling about.The delay results in a temperature rise.
The beauty of ii) is that it decouples the greenhouse effect from the matter of composition leaving atmospheric density as the controlling factor at any given level of solar irradiation. It is the matter of composition that so distresses AGW proponents but in fact it is irrelevant. ALL molecules at or near the surface are involved whether they be GHGs or not.
There has been some confusion caused by Harry Huffman, Claus Johnson and others by virtue of their contention that there is no greenhouse effect when actually they mean that i) above is untrue whilst they accept ii) to be true (I think).
So there is a greenhouse effect but it is not significantly affected by GHGs. In so far as GHGs do have an effect it is negated by faster removal of energy to space by various means (especially evaporation on a water planet) because pressure places a limit on the amount of kinetic energy that can be retained by gases at the surface.
Or have I missed something?
File Under Correlation Is Not Causation:
A legitimate question is posed:
“Why is the atmosphere of Venus approximately the same temperature as the earth at the same pressure level when Venus is so much closer to the sun?”
The correct answer is:
The albedo of Venus is 0.70 while the albedo of the earth is 0.30. The lesser distance from the sun is precisely negated by the higher albedo.
Any questions?
Further to my comment above regarding the spurious nature of back radiation, you would think that someone among all the AGW proponents would have set up a simple experiment such as this to measure the assumed warming effect of back radiation and, at the same time, proving it exists …
Obtain two identical metal plates painted soot black with accurate thermometers attached. Place them on similar ground but at a reasonable distance from each other (a) at night and (b) in the open shade of a large building in daylight hours. Shield one with a larger reflective plate or upward facing mirror and observe if the back radiation received by the other leads to any difference in temperature. Subsequently shield the other and repeat the experiment in case there are unknown variables.
Yet another experiment: Paint one of the plates grey and this time place then vertically and parallel to each other and reasonably close in open air. Heat the black one to, say, 100 deg.C and time how long it takes to return to say 80 deg.C. Now warm the grey one to 80 deg.C and retain that temperature with a thermostatic device. Again measure how long the black one takes to cool from 100 deg. to 80 deg.C in order to determine if it is absorbing any thermal energy from the cooler grey one, such absorption slowing the cooling process.
Anyone taking bets?
http://climate-change-theory.com says:
December 29, 2011 at 4:08 pm
I thank you for your contribution to this discussion. The kind of post that we are discussing should involve some perspectives that are not part of mainstream climate science. Unfortunately, there are those whose comments on this post could be the work of mainstream climate scientists who are doing nothing but enforcing the tautology that “radiation only” theory has become. This blog should be a place for open minds rather than a place where one view of “the truth” is rigorously enforced.