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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This post is also available as a PDF document here:
Unified_Theory_Of_Climate_Poster_Nikolov_Zeller
UPDATE: This thread is closed – see the newest one “A matter of some Gravity” where the discussion continues.
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Do I hear deathly silence from the Lazy Teenager and R Gates?
Joel Shore said:
“The only way that this can be explained is by the fact that the Earth’s atmosphere is not transparent to the radiation emitted by the Earth’s surface…i.e., there are elements in the atmosphere that absorb that radiation (and subsequently emit it…but at a lesser intensity).”
But that is what they do say and what I said back in May 2008.
The density of the atmosphere results in exchanges of kinetic energy beteween ALL molecules of the atmosphere which delays the exit of radiative energy to space.
The radiative characteristics of the molecules are irrelevant because they ALL share in the kinetic activity and the level of that kinetic activity is density/ pressure dependent NOT composition dependent.
From Mark K.
“John Wilkes Booth says:
December 29, 2011 at 7:25 am
“a) the product P×V defines the internal kinetic energy of a gas (measured in Jules) that produces its temperature; ”
This is wrong and anyone with an air compressor can prove it. Pressurize a tank of air. It will initially be warmer according to the idea gas law. But wait a few days. Its temperature will equalize with the ambient air outside the tank. Yet the pressure and volume of the compressed has not changed.
———————————————————————————-
As I understand it, you are leaving out the fact that that in the atmosphere, the energy load is continuously replenished by the sun, balancing (with the help of other mechanisms) the energy loss with energy gain. Thus the formula works. In your example you have only nett loss to the cooler ambient environment. To summarise in my own simplistic way: The energy load of the atmosphere per molecule determines the potential for temperature. The actual temperature achieved is then, for a given energy load, dependant on the pressure (hence compression) experienced by the atmosphere, bringing the molecules closer together. The higher rate of impingement of molecules on each other due to the closer proximity registers as temperature.
Ok, all you very smart persons out there… do have that right in laymans’ terms? 🙂 Makes perfect sense to me. but what do I know.. (TIC)
http://hockeyschtick.blogspot.com/2010/09/shattering-greenhouse-effect.html
Where JAE states
That too has also been a thorn in my side concerning the ‘GHE’ explanation. After giving convection, conduction and gravity more thought, the idea of ‘back radiation’ being the dominant feature just doesn’t make much sense. Surely convection is not properly accounted for.
DirkH says:
John, the Ideal Gas Law assumes that the volume of the container holding the gas is infinitely larger than the volume taken up by the gas molecules themselves, so a compressor might not be the right device to test the Ideal Gas Law.
Exactly. John’s example assumes that the Earth’s atmosphere operates like a compressor which is laughable. This is no different than the now debunked “simple experiment” in which a jar with CO2 is shown to warm faster than a jar of air… it only works that way if you limit the expansion of the gas (like John’s compressor). When you take the lid off the jars and allow the gas to expand then the jar with CO2 warms at the same rate as the jar of air.
Nikolov and Zeller point here to several issues that are important and either ignored completely or examined insufficiently. Specifically these are: 1) the importance of actual temperature distribution on radiative equilibrium and mean surface temperature; and 2) the impact of convection on radiative equilibrium. Unfortunately the glaring errors in application of the gas law will detract from their work, and people will miss the value of the several good suggestions they make.
This will be a busy thread today I predict.
I was right! You’ve just captured what I’ve been working on. I’m a former lukewarmer, but I’ve been pretty convinced lately that GHG’s do nothing more than change the behavior and timing of convective events, nothing more. Net effect of GHG’s to temperature is zero, zip, nada, zilch.
Brilliant work. I thought I was alone on this one. Groundbreaking stuff. Thanks.
Now let’s try to tear it apart… gently.
@John Wilkes Booth: Your statement about pressure in a gas cylinder being independent of temperature is just wrong. The mechanical work of compressing a gas transfers heat, so a newly filled cylinder will cool over time if the ambient temperature is lower than the T of the gas. Pressure will also drop in proportion to the change in T, since the volume is fixed. Heating the cylinder will increase the pressure; relieving the pressure will cool the cylinder. This is all very well understood and easily demonstrated.
ChE says:
December 29, 2011 at 8:56 am
“Sorry, I’d really like to buy some of this, but there’s way too much handwavium. For example, you learn in undergrad thermo that for a diatomic gas like air, ”
Air is a diatomic gas?
We also have the Faint Young Sun paradox to resolve – solar irradiance was as much as 27% lower when the Earth formed (increasing in close to a straight line in the time since).
The Earth should have been a frozen snowball until about 500 million years. It was actually very cold once Oxygen became prevalent about 2.4 billion years ago to about 580 million years ago, but the earlier periods seem to have been warm enough. Perhaps Oxygen thinned out the early atmosphere. Perhaps the early water vapour content (the oceans formed as water vapour rained out of the atmosphere) provides another part of the picture.
John Wilkes Booth:
“This is wrong and anyone with an air compressor can prove it. Pressurize a tank of air. It will initially be warmer according to the idea gas law. But wait a few days. Its temperature will equalize with the ambient air outside the tank. Yet the pressure and volume of the compressed has not changed.”
First, I submit that in your experiment the pressure will in fact have lowered after you have waited those few days. Second, your experiment does not include the inflow of external energy that Nickolov & Zeller discuss below. And your comment suggests that you do not understand that they are already aware of your objection.
Nickolov & Zeller: “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.”
come on people when you pump a tire it gets hot from the work not the preasure, I don’t buy this.
Great, but who… besides shunned skeptics, will read this paper, and give it appropriate consideration?! The IPCC will certainly ignore it, and MSM will minimize it, if acknowledged. No amount of logic and physical science seems capable of piercing the agendized armor of the AGW industry and politics. The gatekeeper team have not fallen asleep. Unlikely academic revolution, would be required. GK
Kevin Kilty says:
December 29, 2011 at 8:37 am
“I think the misunderstanding of the gas law, that temperature is not determined by pressure, is this contribution’s glaring flaw.”
quote from Ned and Karl excellent (adventure) post: “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.”
So according to you stars get hot, then the pressure increases. HMMMM. Weary interesting. By the way would you please call the folks at Cummins Diesel and let them know how wrong they are.
Further, comparing a solid (overcoat) to a gas I don’t think qualifies as a quote of the weak.
Great discussion. BadChoiceOfScreenName is the one who deserves the epic fail for bringing up credentials. State your case for or against the content of the poster. Your comment about “credentials” is utter nonsense unless we are discussing research on the relationship between credentials and scientific discovery. If that were our focus here, you would fail on your position thoroughly.
Refreshing! Bracing! This theory schematic might very well lead to the well confirmed physical hypotheses that climate science needs to break out of its infancy. This account contains many interesting new ideas, especially its treatment of convection, and gives proper place to natural processes that make up our atmosphere. By contrast, Warmists accounts use a radiation only model that studiously ignores all contributions from natural processes other than radiation and leaves us with all kinds of puzzles, especially the grand one as to how back radiation actually increases temperatures at the surface. Well done.
Slow down. Read Leornard Weinstein’s post. Jeff L, and even Joel Shore. The celebration is premature, again.
Alex: “come on people when you pump a tire it gets hot from the work not the preasure, I don’t buy this.”
What part of the N&Z explanation don’t you understand:
“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. “
Try pumping a tire out here in West Texas or Eastern New Mexico in August and see who gets warm fastest. Ya and it last until you jump in the first water tank at the first wind mill.
Alex:
Adiabatic compression….pressure goes up and so does temperature.
Sorry, basic thermo..
Suggest this…
http://galileo.phys.virginia.edu/classes/109N/more_stuff/flashlets/carnot.htm
lol @ur momisugly the people wishing to refute the Idea Gas Law. People, there is a reason why this is called a law and not a theory or postulate. Look up the difference. There are plenty of things to pick at about this submission. The IGL isn’t one of them. You can assign reasoning and factors which go into it, but you’re not going to be able to get around, PV = nRT. ………. goobers.
Just to comment on a few other things:
Yes…This is taught throughout the world, but not as the most complete understanding of the greenhouse effect but rather as the simplest picture of the greenhouse effect. Hence, to criticize it as incomplete is silly…Everyone knows that it is incomplete. It is not meant to be the most complete or quantitatively-correct model. It is meant to be the simplest picture illustrating the basic effect.
Hölder’s inequality only has a significant effect if the temperature range on the planet is very large on an absolute temperature scale. For the Earth, the temperature range is moderate enough on an absolute scale that the difference between averaging the temperature and taking the fourth root of the average of T^4 is quite small.
What convection does is to basically cause the atmosphere to be unstable when the lapse rate is greater than the appropriate (dry or saturated) adiabatic lapse rate. I.e., convection causes any temperature profile steeper than the adiabatic lapse rate to go back to the adiabatic lapse rate. It is correct that the inclusion of convection reduces the greenhouse effect over what it calculated in the absence of convection; however, it does not reduce it to the extent that these authors claim (because the authors incorrectly assume convection try to relax the atmosphere to a completely isothermal temperature profile with altitude)… And, of course, all quantitative calculations of the greenhouse effect are made using models that include such convection.
Andre says:
December 29, 2011 at 5:06 am
“Anyway Hansen et al’s paleotemperature reconstruction depends on a lot of suppostions, for instance that the isotope ratios of Benthic Foraminifera adequately represent the local sea water isotope ratios. However, the chemical composition and pH play an important role. Moreover different species have different reactions and species die out and new appear all the time.”
Very well said. Consider doing a post on this topic.
What always seems to get lost is the idea that Earth is in a steady-state condition: energy is always coming in, energy is always going out. Such systems tend toward stability.
There are minor variations, of course. Solar activity has a marked effect on incident cosmic rays; cosmic rays, in turn, have a marked effect on cloud formation, thus on albedo. And the Sun is a variable star, on a bunch of different cycles. And the orbit of Earth changes over time as well.
What has long bothered me has been the question of latency: suppose carbon dioxide stored outgoing radiation. How long would that energy be held? It seems to me that, regardless of the latency time (milliseconds or centuries) that stored heat energy would be released, and thus the long-term stability of the atmospheric PVT would not change.
Besides, without a good understanding of the carbon dioxide budget (absorption/release from the oceans, absorption/release from plants, absorption/release from animal life), all of these strongly dependent on temperature, we have little to go on as yet.
Combine our ignorance of the details of the whole C02 budget with the enormous bugger factors used in producing the false hockey stick, and you get exactly what we have now: bogus science.
My money is on Nikolov and Zeller. There have never been SUV’s on Titan or Triton.
Bravo – this will put paid to the alarmists
I thought as much some time ago, but not so elegantly – see http://climate-facts.com