Guest post by Bob Wentworth, Ph.D. (Applied Physics)
I am sometimes shocked by the number of climate change skeptics who are certain that the “Greenhouse Effect” (GHE) isn’t real.
As a physicist, I’m as certain of the reality of the Greenhouse Effect as I am that 1 + 1 = 2.
The GHE depends on physical principles that have been well-known and well-tested for 137 years. There really should be no question as to its reality, among anyone who knows and respects science.
Note that being certain about the GHE being real is different than being certain about Anthropogenic Global Warming (AGW), the hypothesis that human-caused increases in the concentrations of “greenhouse gases” in the atmosphere are causing highly problematic changes in the Earth’s climate.
AGW is a far more complex phenomenon than the GHE alone. One can be skeptical about AGW while totally accepting the reality of the GHE.
I know many readers are deeply skeptical about AGW. I encourage you to consider finding a way to honor your beliefs without denying the reality of the GHE.
Based on everything that’s known about physics, denying that the GHE is real seems to me to be just as wrong-headed as insisting that the Earth is flat. (Any Flat-Earthers here?)
Today, I’m going to do something that will likely be pointless, with regard to its ability to change anyone’s mind. But, for the record, I want to offer it anyway.
I’m going to offer a mathematical proof of the reality of the Greenhouse Effect.
I expect that skepticism about mathematics is likely to be common among folks who deny the reality of the GHE.
Oh, well. So be it.
* * *
There are various ways that the idea of the “Greenhouse Effect” might be expressed. Today, I’d like to focus on a formulation of the GHE that is simple and rigorously provable:
Suppose a planet (or object) absorbs shortwave (SW) radiant energy from the Sun (or another source of illumination), and loses energy by emitting longwave (LW) radiation into space at a known average rate.
Then, it follows that there is a maximum average temperature that the surface of the planet (or object) can have, unless there are materials capable of absorbing (or reflecting) LW radiation between it and space.
If the average surface temperature of the planet (or object) is higher than this limit, then that can only happen because of the presence of LW-absorbing (or reflecting) materials between the planetary surface (or object surface) and space.
When the average temperature of a planetary surface is higher than the temperature limit that would be possible in the absence of LW-absorbing materials in the atmosphere, this is called the “Greenhouse Effect” (GHE).
* * *
This result can be proven if one accepts a single principle of physics:
- The rate at which LW radiation is emitted by the surface of the planet (or an object) is given by the Stefan-Boltzmann Law, Mₛ = 𝜀𝜎⋅T⁴, where 𝜀 is the emissivity of the surface, 𝜎 is the Stefan-Boltzmann constant, and T is the temperature of the surface. (This quantity Mₛ is technically called the radiant exitance from the surface, and is measured in W/m².)
The Stefan-Boltzmann law was deduced based on experimental evidence in 1879, and was derived theoretically in 1884. This law has been a key part of the foundations of physics for 137 years, and has been verified countless times, in countless ways.
The reality and nuances of this law are as well-known and well-tested as anything in physics.
* * *
I will divide the proof into two parts. First, I’ll prove that there is a limit to how high the average surface temperature can be in the absence of LW-absorbing (or reflecting) materials. Then, I’ll show that LW-absorbing (or reflecting) materials create the possibility of the average surface temperature being higher.
Let’s define a few terms:
- T is the temperature of the surface of the planet (or object).
- Mₛ is the radiant exitance from the surface of the planet (or object). The subscript “s” is for “surface.”
- Mₜ is the radiant exitance into space from the top of the atmosphere of the planet (or from the materials associated with the object). The subscript “t” is for “top-of-atmosphere (TOA).”
Each of these quantities, T, Mₛ and Mₜ quantities may vary over the surface of the planet (or object) and vary in time as well.
I will use the notation ⟨X⟩ to denote the average of a quantity X over the surface of the planet (or object) and over some defined period of time.
Thus, the average values of surface temperature, surface radiant exitance, and TOA radiant exitance are ⟨T⟩, ⟨Mₛ⟩ and ⟨Mₜ⟩, respectively.
Let’s average each side of the Stefan-Boltzmann Law:
⟨Mₛ⟩ = 𝜀𝜎⋅⟨T⁴⟩
This is the point where we come to the only fancy math in the entire proof.
There is a mathematical law, first proven in 1884, called Hölder’s Inequality. The general formulation of this inequality is rather abstract, and might be scary to a non-mathematician. However, what the inequality says regarding the current problem is very simple. Hölder’s Inequality says it will always be the case that:
⟨T⟩⁴ ≤ ⟨T⁴⟩
In other words, the fourth power of the average surface temperature is always less than or equal to the average of the fourth power of the surface temperature.
It turns out that ⟨T⟩⁴ = ⟨T⁴⟩ if T is uniform over the surface and uniform in time. To the extent that there are variations in T over the surface or in time, then this leads to ⟨T⟩⁴ < ⟨T⁴⟩.
(One of the reasons the surface of the Moon is so cold on average (197 K) is that its surface temperature varies by large amounts between locations and over time. This leads to ⟨T⟩⁴ being much smaller than ⟨T⁴⟩, which leads to a lower average temperature than would be possible if the temperature was more uniform.)
Combining the inequality with the equation preceding it, one finds:
⟨T⟩⁴ ≤ ⟨Mₛ⟩/𝜀𝜎
In other words, if you know the average radiation emitted by the surface, then there is an upper limit to how hot the surface could be on average.
Let’s consider the case where there are no LW-absorbing (or reflecting) materials in the atmosphere of the planet (or in between the object and space).
It should be clear that in this situation, Mₜ = Mₛ. The rate at which radiant energy reaches space must be identical to the rate at which radiant energy leaves the surface, if there is nothing to absorb or reflect that radiation.
So, in this situation,
⟨T⟩⁴ ≤ ⟨Mₜ⟩/𝜀𝜎
We can re-write this as
T ≤ Tₑ
where the radiative effective temperature Tₑ is given by
Tₑ⁴ = ⟨Mₜ⟩/𝜀𝜎 [equation 1]
In other words, if you know how much radiation is emitted at the top of the atmosphere, and if you know there are no LW-absorbing (or reflecting) materials in the atmosphere, then you can calculate the radiative effective temperature Tₑ and you can be certain that the average temperature of the surface will not be larger than this value.
* * *
Often, the “Greenhouse Effect” (GHE) is expressed in relation to the insolation, or the rate of energy being absorbed by the planet. Under an assumption of “radiative balance,” the average insolation is equal to the ⟨Mₜ⟩, the average rate at which LW radiant energy is emitted into space.
However, there can be small discrepancies between the average insolation and the rate of energy being emitted into space. And, some people who don’t trust climate science dispute the assumption of radiative balance.
So, I’m choosing to offer a formulation of the GHE which is valid even in the absence of radiative balance between the rates of energy being received and emitted by the planet (or object).
If you know the rate at which LW radiant energy is being emitted by the planet (or object), then there is a limit to how warm the planet can be without LW-absorbing (or reflecting) materials.
* * *
What happens if there are materials present that absorb (or reflect) some of the LW radiation emitted by the surface, before it can get to space?
This creates the possibility that the rate of LW radiation being emitted to space could be different than the rate of LW radiation being emitted from the surface. In other words, such materials create the possibility that Mₛ ≠ Mₜ.
Let’s define the “LW enhancement” ∆M as ∆M = (Mₛ − Mₜ).
On Earth, ∆M is generally positive. More LW radiation is emitted by the surface than reaches space. This is possible only because of the presence of materials in Earth’s atmosphere which absorb (or reflect) LW radiation.
(In Earth’s atmosphere, there is more LW absorption than reflection. However, some reflection of LW radiation does occur in the form of LW scattering by aerosols and clouds. For purposes of this analysis, “reflection” and “scattering” are interchangeable concepts.)
If we go back to the inequality above that was expressed in terms of ⟨Mₛ⟩, and apply the definition of LW enhancement, we can rewrite the inequality as
⟨T⟩⁴ ≤ ⟨Mₜ⟩/𝜀𝜎 + ⟨∆M⟩/𝜀𝜎
Applying the definition of the effective radiative temperature Tₑ we can further rewrite the inequality as:
⟨T⟩⁴ ≤ Tₑ⁴ + ⟨∆M⟩/𝜀𝜎 [equation 2]
Equations 1 and 2 together offer a formal expression of the “Greenhouse Effect” (GHE).
What do these equations say? They say that:
- Given the average LW radiant exitance at the top of the atmosphere, you can calculate a radiative effective temperature Tₑ. (To the extent that radiative balance applies, one could alternatively use the average absorbed insolation to calculate Tₑ.)
- In the absence of materials in the atmosphere that absorb (or reflect) LW radiation, it would be impossible for the average temperature of the planet to exceed Tₑ.
- If there are LW-absorbing (or reflecting) materials in the atmosphere, then this creates the possibility of the average surface temperature being higher than Tₑ.
- How much higher than Tₑ the average surface temperature could be is determined by how much the average LW surface radiant exitance ⟨Mₛ⟩ exceeds the average LW TOA radiant exitance being emitted to space ⟨Mₜ⟩.
In this formulation, the GHE refers to the phenomenon of LW-absorbing (or reflecting) materials making it possible for the average surface temperature to be higher than would otherwise be possible.
I’ve shown that a single principle of physics (the Stefan-Boltzmann Law) sets a limit on how high the average surface temperature can be, and says that this limit can be increased if and only if there are LW-absorbing (or reflecting) materials present in the atmosphere.
* * *
How does this apply to Earth?
Earth’s atmosphere includes LW-absorbing-or-scattering materials such as water (in the vapor, liquid and solid phases), aerosols, carbon dioxide, methane, nitrous oxide, ozone, and fluorinated gases.
Equations 1 and 2 allow us to assess whether the LW-absorbing (or LW-scattering) properties of these materials are essential to accounting for the Earth’s average surface temperature.
Let’s put in some numbers. I’ll use poster data from NASA averaged over a 10-year period. (The results wouldn’t be much different if another data source was used.) That data indicates an average LW TOA radiant exitance ⟨Mₜ⟩ = 239.9 W/m².
(The absorbed SW insolation is given as 240.4 W/m², which is almost, but not quite, in balance with the LW TOA radiant exitance. This imbalance is evidence that Earth was not in steady-state, but experienced a net warming over the decade of measurement.)
The data indicates an average LW enhancement ⟨∆M⟩ = 158.3 W/m². As a reminder, the LW enhancement ⟨∆M⟩ isn’t a measure of “back-radiation.” It’s a measure of how much more LW radiation leaves the surface than reaches space.
If we assume an average surface emissivity 𝜀 = 0.94, then equations 1 and 2 lead to:
Tₑ = 259 K (-14℃)
⟨T⟩ ≤ 294 K (21℃)
In other words:
- If there were no LW-absorbing (or LW-scattering) materials in Earth’s atmosphere, and it emitted the same average LW radiant exitance (upwelling LW radiation) to space (which would be expected in steady-state if the absorbed insolation was held constant), then the average surface temperature could not be warmer than Tₑ = 259 K (-14℃).
- Given that Earth’s atmosphere does include LW-absorbing and LW-scattering materials which allow there to be more LW radiation emitted by the surface than what reaches space, the average surface of the Earth can be no higher than 294 K (21℃).
Given that the average surface temperature of the Earth is typically estimated to be about 288 K (15℃), this satisfies the constraint of being no higher than 294 K (21℃).
According to equation 1 and this particular data set, the surface of the Earth is 29℃ warmer than it could possibly be, given the same average LW TOA radiant exitance, if there were no LW-absorbing (or scattering) materials in the atmosphere.
(The more typically quoted figure of 33℃ would result if one assumed an emissivity 𝜀 = 1.)
This result demonstrates that the presence of LW-absorbing and LW-scattering materials in the atmosphere is mathematically essential to explaining at least 29℃ of the Earth’s current temperature, provided only that one accepts the Stefan-Boltzmann Law.
* * *
Note that this result (that LW-absorbing materials are needed to enable the Earth to be as warm as it is) is entirely independent of any details of what happens in the atmosphere and ocean.
Convection, heat engines, ocean currents, thermal storage, turbulence, atmospheric pressure—none of these make the slightest difference to the basic conclusion.
No matter what physical processes happen on Earth, its average surface temperature would be need to be colder, if it were not for the presence of LW-absorbing materials in the atmosphere.
* * *
* * *
* * *
APPENDIX 1: “Proof” in the Context of Science
The term “proof” is generally reserved for mathematics, and is not used in science. In science, one doesn’t “prove” things; one offers evidence that confirms or disconfirms the predictive accuracy of a hypothesis or theory.
So, what do I mean when I say I’m “proving” the GHE?
Technically, I proved that the GHE is mathematically an inherent consequence of the Stefan-Boltzmann Law.
The reality of the GHE effect is equivalent to the reality of the Stefan-Boltzmann Law.
The offered “proof” implies that any evidence confirming the Stefan-Boltzmann Law should also be considered to be evidence confirming the GHE.
There has been enormous evidence over 137 years confirming the predictive accuracy of the Stefan-Boltzmann Law. It is a key component in the foundations of physics.
APPENDIX 2: Does the GHE Offer More Specific Predictions?
Some readers may feel frustrated that the GHE, as I’ve formulated it, doesn’t offer any specific predictions for what surface temperatures should result from LW-absorbing (or reflecting) materials being present in the atmosphere.
Maybe you take issue with the results of climate models and you want to refute the predictions that arise from “assuming the GHE exists.”
Maybe it would be nice to be able to identify “the part of these models that is the GHE” so that that part can be separately tested.
I think this sort of thinking reflects a misunderstanding of the nature of the GHE.
The GHE is not a specific process. It’s an emergent phenomenon that arises from the basic laws of physics.
Modelers do not “add the GHE” to their models. They build climate models using the established laws of physics, with some model components being addressed empirically. (How well models reflect the basic laws of physics may vary.)
The GHE simply arises when one takes the laws of physics into account. It’s not something separate that one adds to a model.
There are no specific predictions that the GHE alone gives rise to. There are only the predictions that arise from the laws of physics. Sometimes, some aspect of these predictions may be attributed, after the fact, to the “Greenhouse Effect.”
But, the GHE is not a separate theory. It’s an observation of the consequences of the fundamental theories that form the foundations of modern physics.
APPENDIX 3: But How Does the GHE Work?
There are a variety of ways of talking about the GHE.
Some approaches focus on explaining how LW radiation absorbing-and-emitting gases can raise the surface temperature. People engaging with such explanations often get mired down in disputing details.
In this essay, I’m taking a different approach. What I’ve offered here makes no attempt to explain how LW-absorbing (or scattering) materials can raise the average surface temperature.
Instead, I’m offering an analysis that simply says, if a planetary surface exceeds a certain average temperature, Tₑ, then it’s certain that LW-absorbing (or scattering) materials must play an essential role in whatever process causes this warming to happen.
While the approach in this essay doesn’t offer any explanation of “how,” it arguably makes up for that by being so ridiculously simple that there would appear to be no legitimate loopholes for disputing it.
If you follow the logic offered here, it should be clear that the GHE is real.
Once one has accepted the GHE as real, I imagine there might be more motivation to work through and understand the explanations offered elsewhere about how the GHE works. Without being committed to trying to prove the GHE wrong, it is likely to be easier to understand how works.
(Do I expect that anyone will follow this path? Probably not. Yet, I’ve done what I can to offer the opportunity.)
APPENDIX 4: Variations in Emissivity
An astute reader might notice that the analysis above did not account for variations in the emissivity, 𝜀. If one takes this into account, the key equations become:
Tₑ⁴ = ⟨Mₜ/𝜀⟩/𝜎
⟨T⟩⁴ ≤ Tₑ⁴ + ⟨∆M/𝜀⟩/𝜎
This refinement to the result doesn’t change the basic conclusion.
A majority of the Earth’s surface is ocean with an emissivity of about 0.96. Emissivity on land is mostly greater than 0.9, though it sometimes dips lower. Suppose we conservatively estimate 67% of the planet to be open ocean with an emissivity of 0.96, estimate that 80% of land has an emissivity of at least 0.85, and the remainder has an emissivity of at least 0.6.
This would lead to an effective emissivity, for purposes of calculating Tₑ, of about 𝜀ₑ ⪆ 1/(0.67/0.96 + 0.264/0.85 + 0.066/0.6) = 0.89. While this is a crude calculation (and ignores the need to weight in proportion to the TOA radiant exitance), it represents an approximate “worst case”; the actual effective emissivity will be higher than this.
An effective emissivity of 0.89 would lead to Tₑ = 263 K (-11℃). This is still about 26℃ colder than Earth’s observed average surface temperature.
Excellent piece. Thank you Dr. Wentworth.
So if CO2 drives temperature how come Mars is freezing and Venus boiling, both with v similar amounts of CO2 in their atmosphere.
Just wondering?
Where did you see or read “…CO2 drives temperature…” ?
He read it in this post where after all of his long winded and extremely condescending and ignorant ranting about “flat earthers” and “math non-believers” – both of which proved the author is an ignorant ahole who does not deserve a PhD in anything but political science – where the guy wrote that the only way that the temperature of the planet can be higher than his model said is it is if it is greenhouse gas effect. He totally ignores geothermal heat inputs to the surface temperature and heat transference.
Actually, what I have presented is valid in the presence of “geothermal heat inputs to the surface temperature and heat transference.”
The derivation makes no assumptions about the source of heat. I mentioned heat from sunlight, but the argument would be equally valid if 100% of the heating was geothermal.
As to “heat transference”, I’m not certain what you mean by that. However, if you’re referring to there being mechanisms to transfer heat between different locations on Earth or in its atmosphere, any and all such mechanisms are also accounted for in what I’ve presented.
The result relates to a distribution of surface temperatures, and the relationship with the amount of radiation emitted to space.
The conclusion is valid no matter what the heat source is, and no matter how heat is transferred.
* * *
If you found some of my comments “condescending,” then I apologize for that.
You made generalised condescending characterisations. Most people here understand and accept GHE, because they were or still are professionally involved in technical occupations and have reasonable skills and understanding of mathematics and physics.
Most people understand and accept GHE by numbers fed to them. But the numbers are wrong, 390 > 240 means 150 unexplained excess energy but not 501 < 390 max. 111 isn’t needed and is reflected. No unexplained excess energy is labelled the GHE. Having the correct data changes the understanding of science.
The flat earth comment is over-the-top, I agree. There are plenty of ways that a person can deduce with his own eyes that the earth is not flat and would truly need to be deranged or disingenuous to claim a belief in a flat earth given the opportunities in today’s society to observe contrary evidence.
It’s not so accessible to experience the Stefan Boltzmann law in daily experience. On a different angle, it’s understandable that people have experience with gases heating up when work is done on them and then they draw the wrong conclusion that pressure produces heat (rather than work producing heat), or even less defensibly that static pressure somehow maintains heat.
I hope that some people will read this article and understand that there is such a thing as a greenhouse effect but that it doesn’t mean that there is dangerous warming from it.
I hope my comments about convestion and temperature pressure relationships aren’t believed to be among those claiming “pressure produces heat”. I believe no such thing but I do claim there is a pressure-temperature relationship. T=P/V, given two masses of gas containing the same amount of thermal energy, the one under more pressure has less volume and a higher temperature.
PV=nRT
The so-called ideal gas law, shows the relationship among pressure, volume, and temperature in an idealized case.
T is therefore proportional to PV, not P/V. But where the “pressure creates temperature” idea goes wrong is in the direction of causality. In reality T is the independent variable (arising from solar radiation) that causes the volume to adjust when a certain number of moles of gas are in a gravitational field. The mass of the atmosphere over the surface of the planet determines the pressure at sea level.
If the sun stopped shining, or the earth were somehow flung out of orbit into intergalactic space, the entire atmosphere would cool and shrink down, eventually condensing and finally solidifying. At that point pressure approaches zero.
As it is, the height of the atmosphere varies substantially due to temperature from a maximum in the tropics to a minimum at the poles. Clearly it is the sun’s heating that is driving the bus, not pressure.
Yes, I mis-stated. T=PV, not P/V.
And the sun does provide the energy.
“P” is determined by the mass of the overlying atmosphere as you say and is lower at higher altitudes.
Assuming an atmosphere transparent to incoming radiation the surface will warm and the lower atmosphere will be warmed and then rise to be replaced by downfalling atmosphere. The rise will be mostly adiabatic causing expansion and cooling as the pressure decreases (both P and V decrease causing T to decrease). the result is an atmosphere with a lower pressure, temperatuee and density at higher altitudes due mostly to the pressure difference.
Other effects cause temperature to be higher at altitudes where the atmosphere is ethereal.
I think I learned that there was a temperature / pressure relationship in my Thermodynamics classes in high school. We got to learn on a running broiler 20ft diameter flywheel that produced heat for the building for sure but I think also electricity. I also seem to remember a text book that was all tables of temperature vs pressure. Of course it was for superheated water which only occurs in real life in the AGW 8.5 case. We are going to be hotter than Venus.
I was expressing frustration with the rather vocal subgroup that do not understand and accept the GHE.
I regret that I didn’t express myself with more grace and care.
If you wanted to take a pop at your ‘strawmen’, why didn’t you use a straw-duvet analogy? Adding them gives you more GHE, reducing them gives you less .
And, you ought to have talked about the relative effectiveness of the various GHGs, starting with H2O ……
Bob Wentworth
Bob let’s see.
Two things to consider.
Do you think that according to your mathematical proof of GHE and the conclusions you arrive at and offer;
“All that,
is it in harmony and compatibility with M.Cycles (Effect)?”
and the other;
“Do not your conclusions in consideration of GHE as you uphold it, suggest that there can not be an atmosphere at all without GHG and the GHE?
cheers
I don’t see why what I’ve written wouldn’t be in harmony with and compatible with the existence of Milankovitch Cycles.
Why would you think my conclusions would suggest that?
There is no reason, for example, that a planet couldn’t in principle have a pure nitrogen or pure argon atmosphere.
And it would be warmer than without.
You mean a planet with a pure nitrogen or pure argon atmosphere?
Somewhat warmer, but limited to being no warmer on average than the radiative effective temperature, Tₑ.
The reason it would be warmer than a planet without any atmosphere is that a nitrogen or argon atmosphere could still develop atmospheric circulation patterns to transfer heat from low latitudes to high latitudes.
This would reduce the magnitude of temperature variations across the planet.
Smaller temperature variations means that ⟨T⟩⁴ can be closer to ⟨T⁴⟩, i.e., a warmer average temperature, though ⟨T⟩⁴ ≤ ⟨T⁴⟩ = Tₑ⁴ will still apply because of the absence of LW-absorbing/scattering materials.
But that is where the ionosphere comes in! No?
I’m not following. What is “where the ionosphere comes in”?
N2 A atmospheres presumably sport an ionosphere re-reflecting ir back to earth simulating your GHE.
If an ionosphere absorbs and re-radiates some thermal radiation, that wouldn’t “simulate” the GHE, it would “be” an example of the GHE.
However, to the extent that the ionosphere does this, I have an impression that this is a far weaker effect than the effect currently produced by GHGs.
I view the ionosphere as the glass in our global greenhouse. See radio communication. Ions are excellent ir reflectors and they are present in a greater number, density and locality than CO2 as an agent to effect ir down-swelling. And, as we see below, emission by the no density of CO2 is too small to explain any measurable warming.
Exactly.
The GHE and M.Cycles (Effect) are the two main pillars of the Radiative theory of climate, or should we say the already non disputable “wisdom” of climastrology,
which actually completely fail to explain the reality of the last 150 years in their own, without the further support from AGW hypothesis.
The reality of ~140 ppm of CO2 and 1-1.2C upswing.
Both Pillars of that “wisdom” support each other as an
explanation of climate… with AGW build on top of,
and further supporting that construct.
In proposition of climate;
one of them three falling, the whole premise or the construct of radiative theory of climate collapses.
As for your conclusions, do you say that our Earth with the surface at -14C temp average there, would have an atmosphere at all?
Our watery planet having an atmosphere, at -14C average surface temp.?
Just asking.
Is GHE a real feature?
Yes, as real as M. Cycles feature.
But the effect of both, in climate or Earth’s surface temp., is almost non existent.
cheers
Well, nitrogen and oxygen need to get way colder than that before they freeze out. Wouldn’t be much water vapor though.
So you say that Earth would have had an atmosphere at -14C average surface temp.
Wow, Bob.
Is it just me, or you just went @ur momisugly full “de javu” on me!
😳
From your derivation:
It should be clear that in this situation, Mₜ = Mₛ. The rate at which radiant energy reaches space must be identical to the rate at which radiant energy leaves the surface, if there is nothing to absorb or reflect that radiation.”
A clear assumption that only radiative energy can be involved in the transfer. You absolutely DO NOT account for “any and all such mechanisms”.
All I assumed is that only radiation is involved in radiant energy transfer. That’s the definition of radiant energy transfer.
There are no assumptions whatsoever about what other forms of energy transfer may be present.
My statement is logically equivalent to saying “If I shine a flashlight at a wall, and nothing intercepts any of that light, then it will all reach the wall.”
An analogy worthy of some thought on my part but I will argue that there is still something missing in the essay.
Geothermal inputs are 4 or 5 orders of magnitude lower than what is coming in from the sun.
Ignoring it is a very logical thing to do.
The math was presented, do you believe it or not? If you don’t believe, refute it. Don’t just whine about how the guy offended your delicate sensitivities.
The facts about CO2’s abilities to absorb energy have been well documented for well over a century. To deny such basic science is well the equivalent of being a flat earther.
Mark,
is not about believing or not.
The math presented and the following conclusions are completely incompatible with reality… regardless of what one believes or not.
cheers
CO2 may absorb energy but it is an insignificant amount in the troposphere. TOA above equator 80 watts remaining. couple of hundred grams of mixed gases. 1000-460(insulation) 540 watts reflected. How much of 540 is retained by CO2? close to zero. As is the 460 watt insulation amount. CO2 absorbs some of the 79 watts at 15µm. Nothing below that wavelength.
Yes, the energy absorbed by CO2 at 15 microns is about 1/25 the energy supplied by sunlight at 0.6 microns (assuming the average waelength of visible light–the same assumption used in calculating radiative energy W/m2.
?w=545&h=307
The CO2 effect is over on the far left; it is as negligible as geothermal.
For anthropogenic CO2, at 287.64K (stated average global temperature) and for radiation between 13.98352 µm – 15.98352 µm (to account for the absorption shoulders of CO2), and to be exact: 0.29652933849 W m-2, which I address in the text below.
—–
If ‘backradiation’ from CO2 emission causes CAGW, where is it coming from?
14.98352 µm near-surface extinction depth is ~10.4 m at 415 ppm, and ~9.7 m at 830 ppm. The troposphere is opaque to 13.98352 µm to 15.98352 µm (to account for the absorption shoulders of CO2) radiation. In fact, it’s opaque to that radiation right up to ~15 – 20 km (TOA for that wavelength of radiation). That’s where the effective emission height of CO2 is.
CO2’s tropospheric absorption of IR thermalizes that radiation and thus increases CAPE (Convective Available Potential Energy), which increases convection of air to the upper atmosphere (carrying with it the latent and specific heat of polyatomic molecules… more polyatomic molecules will carry more energy and will more readily emit that energy in the upper atmosphere), which is a cooling process.
Radiation MFPL decreases exponentially with decreasing altitude and vice versa due to changing air density, so the net vector in the 13.98352 µm to 15.98352 µm band is upward, so the majority of ‘backradiation’ which could possibly reach the surface would be from that thin layer of atmosphere which is within ~10.4 m of the surface, and the great majority of that energy is thermalized and convected. So where’s this ‘backradiation’ energy coming from that’s going to cause CAGW, especially considering that the maximum able to be absorbed by CO2 is 8.1688523 W/sr-m^2, and the maximum able to be absorbed by anthropogenic CO2 is 0.29652933849 W/sr-m^2?
At 287.64 K (the stated global temperature) and an emissivity of 0.93643 (ref: NASA’s ISCCP program, data collected 1983-2004), at 14.98352 µm photon wavelength, spectral radiance is only 5.43523 W / m^2 / sr / µm (integrated radiance from 13.98352 µm – 15.98352 µm of 10.8773 W/sr-m^2).
Thus the maximum that CO2 could absorb in the troposphere would be 10.8773 W/sr-m^2, if all CO2 were in the CO2{v20(0)} vibrational mode quantum state.
While the Boltzmann Factor calculates that 10.816% of CO2 are excited in one of its {v2} vibrational mode quantum states at 288 K, the Maxwell-Boltzmann Speed Distribution Function shows that ~24.9% are excited. This is higher than the Boltzmann Factor because faster molecules collide more often, weighting the reaction cross-section more toward the higher end.
Thus that drops to 8.1688523 W/sr-m^2 able to be absorbed. Remember, molecules which are already vibrationally excited don’t absorb radiation with energy equivalent to the vibrational mode quantum state energy at which they are already excited. That radiation passes the vibrationally excited molecule by (unless there are degenerate vibrational mode quantum states… there are three for CO2):
CO2{v21(1)}: 667.4 cm-1, 14.98352 µm
CO2{V22(2)}: 667.8 cm-1, 14.97454 µm
CO2{v23(3)}: 668.1 cm-1, 14.96782 µm
That’s for all CO2, natural and anthropogenic… anthropogenic CO2 accounts for ~3.63% (per IPCC AR4) of total CO2 flux, thus anthropogenic CO2 can only absorb 0.29652933849 W/sr-m^2.
CO2 absorbs ~50% within 1 meter, thus anthropogenic CO2 will absorb 0.148264669245 W/m^2 in the first meter, and the remainder 0.148264669245 W/m^2 within the next ~9 meters.
CO2 absorbs this radiation regardless of any increase in atmospheric concentration… 14.98352 µm extinction depth is ~10.4 m at 415 ppm, and ~9.7 m at 830 ppm. Any tropospheric thermalization which would occur at a higher CO2 concentration is already taking place at the current concentration. Thus the net effect of CO2 thermalization is an increase in CAPE (Convective Available Potential Energy), which increases convective transport to the upper atmosphere, which is a cooling process.
Tropospheric thermalization is saturated. A doubling of CO2 doesn’t appreciably reduce extinction depth at 14.98352 µm. But upper-atmospheric radiative shedding of energy to space is not saturated… more CO2 molecules will cause more upper-atmospheric cooling, increasing buoyancy of lower-atmosphere air and thus increasing convection. IOW, polyatomic molecules (CO2, H2O) increase thermodynamic coupling between heat source (ie: surface) and heat sink (ie: space) due to the fact that they have higher specific heat capacity than the monoatomics (Ar) and homonuclear diatomics (N2, O2).
An increased CO2 concentration will emit more radiation in the upper atmosphere (simply because there are more molecules absorbing energy in the lower atmosphere, more molecules convectively transporting energy to the upper atmosphere, and more molecules capable of emitting radiation in the upper atmosphere), thus more radiation will be emitted to space, and that represents a loss of energy to the system known as ‘Earth’, which is a cooling process.
This illustrates what I’m stating:
http://imgur.com/Zxq4KlB.png
That’s a MODTRAN plot at 287.64 K for 415 ppm vs. 830 ppm CO2 for 13.98352 – 15.98352 µm radiation. A doubling of CO2 concentration doesn’t appreciably change tropospheric upward or downward radiative flux (because extinction depth at those wavelengths is low enough that it’s thermalizing nearly all of that radiation, the net effect being an increase in CAPE as discussed above), but it does change how much energy is exiting the system known as ‘Earth’, and that represents a cooling process. That cools the upper atmosphere, and since the lapse rate is ‘anchored’ at TOA and the heat transfer equation must (eventually) balance, and because a higher concentration of polyatomic molecules shifts the lapse rate vertically and radiatively cools the upper atmosphere faster than the lower atmosphere can convectively warm it, the surface must cool with an increasing CO2 atmospheric concentration. This is what is taking place, we’re just working through the thermal capacity of the planet, which warmed due to a now-ended long series of stronger-than-usual solar cycles (the Modern Grand Maximum), but it is cooling (in fact, it’s projected that we’re slipping into a Solar Grand Minimum which will rival the Dalton Minimum, and may rival the Maunder Minimum).
Zoomed in…
Note the extreme right-hand edge of that chart… negative and decreasing at an accelerating rate.
Spectral Cooling Rates For the Mid-Latitude Summer Atmosphere Including Water Vapor, Carbon Dioxide and Ozone
CO2-induced spectral cooling rate (positive scale) extends to the planet’s surface, whereas CO2 shows just a bit of warming (negative scale) only at the tropopause (ie: just above the clouds, where it absorbs a greater percentage of cloud-reflected solar insolation and radiation from cloud condensation).
Polyatomic molecules shift the lapse rate vertically, more of them shifts the lapse rate more vertically (which attempts to decrease temperature differential between different altitudes by transiting more energy from surface to upper atmosphere), while also radiatively cooling the upper atmosphere faster than the lower atmosphere can convectively warm it… ie: they are coolants.
This is borne out empirically by the long-term and dramatic upper-atmosphere cooling and by the fact that OLR increased by ~7 W/m^2 over ~72 years even as surface temperature showed no statistically significant trend for more than two decades (said increased OLR partly caused by the increasing CO2 concentration making available more molecules capable of efficiently convectively transporting energy to the upper atmosphere, then radiatively emitting it).
Brilliant.
I’m fairly certain the math above won’t work if you limit it to a marginal trace gas that near saturation.
I’m also fairly certain that it will work if you ignore CO2 and just use water vapor/aerosol content.
One of the facts known about CO2 abilities for over a century are its limits.
The math is irrelevant, especially it it’s the same math used to inform the 100+ climate models. Empirical evidence tends not to support AGW.
Rory, Without antagonism intended on my part, I think you have misread the head post, or tripped over the flat-earther comments and failed to read it.
The main point has nothing to do with AGW. It is a discussion about the natural greenhouse effect mostly due to water vapor.
Anyone who feels the need to begin with a preamble, filled to the gunnels with as many fallacies as he can fit in, isn’t worth reading. Surely you don’t believe this is the first time anyone has written such a “proof”, do you? The issue has never been about the role of water vapour, in general, plays in our planet’s climate system. The point is ONLY about the role of CO2, misnamed “carbon”.
If he’s not stating that the science has been misused to perpetrate a massive fraud, he’s a waste of space. If he’s redundantly restating the GHE, he’s a pompous ass.
I don’t believe the author makes this claim in this post.
Correct, Jeffery!
The author specifically said that the fact that CO2 is a radiative gas does not imply that it controls temperature.
The two propositions are separate.
In order for CO2 to drive temperature, it would have to mean that massive amounts of evidence from Earth history and more recent proxies as well as direct measurements since we have had the ability to make them, would all have to be incorrect. Like, totally wrong.
It does not.
But even if it did, it would not matter, because the earth is too cold and it would be good, not bad, if the planet warmed up a whole bunch.
The warmista case is not proven in any slight degree by acknowledging that CO2 has the radiative properties that allow it to intercept and redirect photons of certain wavelengths.
The radiative properties of substances is very well understood.
It is how all the factors interact to produce the ever changing climate regimes of our planet, that no one has proven that they have any complete understanding of.
Correct, Jeffery!
The author specifically said that the fact that CO2 is a radiative gas does not imply that it controls temperature.
The two propositions are separate.
In order for CO2 to drive temperature, it would have to mean that massive amounts of evidence from Earth history and more recent proxies as well as direct measurements since we have had the ability to make them, would all have to be incorrect. Like, totally wrong.
CO2 categorically does not drive temperature, and CO2 is categorically a radiative gas.
However one may feel about whether the terminology known as “the greenhouse effect” is apt or not, gasses that intercept certain wavelengths of photons do exist, and one of them is CO2, and another is H2O, and some people have taken to using this terminology.
Another red herring is this idea some people seem to have that if “The Greenhouse Effect” is a poor or even a wrong analogy to make, it somehow follows logically that therefore CO2 does not have radiative properties.
This too is false and is not even slightly logical.
CO2 does not control the temperature of our planet.
But even if it did, it would not matter, because the Earth is too cold, and it would be good, not bad, if the planet warmed up a whole bunch.
CO2 has been far higher in the past.
Many times.
It made for a more robust biosphere.
The Earth has been far warmer than it is now.
It was not a catastrophe, it was the opposite…it was a boon for life, and the planet was far more hospitable when it was warmer, and life prospered in profuse abundance from pole to pole, with no huge regions of our planet perpetually locked into a state of being frigid wastelands.
The catastrophe was when the Earth grew cold and entire continental regions, and even an entire continent, were wiped clean of life.
The warmista case is not proven in any slight degree by acknowledging that CO2 has the radiative properties that allow it to intercept and redirect photons of certain wavelengths.
The radiative properties of such substances are very well understood.
It is how all the factors interact to produce the ever changing climate regimes of our planet, that no one has proven that they have any complete understanding of.
Earth history proves that CO2 is NOT the thermostatic control knob of the planet.
Earth history proves that a warmer world is not dangerous.
Warmistas are liars who make up phony data and toss real data, collected by tens of thousands of people, over hundreds of years, into the garbage.
They are crooks who want to fleece and impoverish us all.
When people who know that these things are true, are nevertheless arguing with each other, instead of directing our attention where it matters, we are doing the warmistas a big giant favor, and making it easier for them to do what they are doing and want to continue to do.
First, they have nothing like the same amount of CO2 in their atmospheres: the surface pressure on Venus is about 90x Earth’s atmospheric pressure, and most of it is CO2. The surface pressure on Mars is about 1/100 that of Earth–again, mostly CO2. So the surface pressure on Venus is 90 * 100 = 9000 times greater than that on Mars.
Also relevant, although for some reason seldom mentioned in the context of warming, is that Venus is about 0.72 * as far from the Sun as the Earth, while Mars is about 1.5 * as far from the Sun as the Earth. So Mars is about 1.5/.72 = 2.0x further from the Sun than Venus, meaning it receives 1/4 of the amount of sunlight.
Venus however has high albedo. About 76% of sunlight incident at the top of its atmosphere is reflected away. Only some three percent reaches the surface directly, while perhaps another seven percent arrives after scattering. The rest is absorbed in the dense air.
Despite so little solar radiation hitting the ground, Venus is hot because it turns so slowly and its thick atmosphere and high winds keep the surface from cooling off during its long nights. Some heat might also move through the lithosphere from the day side to the dark.
A tall column of gas molecules in a gravitational field sorts itself into hot molecules at the bottom of the column and cool slower moving ones higher up that have slowed down in their climb upwards against gravity. This is the “adiabatic lapse rate”. Venus has about 60 km of adiabatic lapse rate from its effective radiation altitude down to surface. At about 11 degrees per km. Thus over 700 degrees K at surface…
See Figures 6 to 11 here:
https://arxiv.org/pdf/1806.06835.pdf
I think it’s nice that people can write a well thought out and accurate paper about the atmosphere of venus that would likley be “cancelled” if it were written about the Earth.
Sad but true. Jim “Venus Express” Hansen’s PhD thesis posited a Venusian situation which he knew to be false.
It’s akin to potential temperature in meteorology, solid physics, not really anything that can be cancelled…
That paper offers a nice analysis of the adiabatic lapse rate on Venus.
Are you under the impression that the lapse rate calculation somehow explains the surface temperature?
A lapse rate only establishes the relative temperatures of different parts of the atmosphere.
It doesn’t say anything about the absolute temperature.
Shift all the temperatures up or down by 10 K, and you’d still have the same lapse rate.
As you note, the adiabatic lapse rate explains the temperature in its classic interpretation, in a stable atmospheric column. Adiabatic means NO heat transfer. Allow radiation to exit or enter at the top or bottom of the column and the temperature is little different because there IS heat transfer. Put a radiative gas like CO2 in the column instead of N2 (which is IR transparent), and there is a bigger difference, caused by heat transfer between the “layers” of CO2. A temperature profile can be calculated. Mannabe and Moller did it in 1961…
I’m still not clear whether you think this discussion of adiabatic lapse rate has anything to do with the GHE or with explaining planetary temperatures.
To be clear, I do NOT believe the adiabatic lapse rate explains the surface temperature.
I believe it only explains the relative temperatures of surface and various parts of the atmosphere.
Venus’ temperature does not differ between night and day.
Seems the atmosphere is just to well mixed.
“First, they have nothing like the same amount of CO2 in their atmospheres”
As a percentage, they do. Venus it’s 96.5%, Mars it’s 95.97%, whereas Earth it’s a mere 0.0413%. Warmistas are constantly harping on the increase in the parts per billion (the 350 in 350.org for example) which is an expression of percentage. Clearly, as you point out, it’s not the percentage that is the all important factor, but rather the other elements you discuss.
So how does surface pressure affect “greenhouse gas effect” such as it is claimed. There is no variable in any of the models cited by this author that include atmospheric pressure, or density of the atmosphere in grams per cubic meter.
You do realize that even though Earth’s atmosphere is 100 times denser than Mars’ atmosphere, that the mass density of CO2 in Mars’ atmosphere, which is 95.32% CO2, is still massively greater than the mass density of CO2 on Earth, which is only 0.04% CO2.
Do the math … 95.32% divided by 100 is still 24 times greater than 0.04%, adjusting for relative densities.
I’m not certain what you are trying to imply but I will note that “There is no variable in any of the models cited by this author that include atmospheric pressure, or density of the atmosphere” demonstrates conclusively that the author has not considered all the pertinent variables.
I didn’t imply anything. I wrote it all down. It speaks for itself.
The commenter whom I responded to, apparently whom you didn’t bother to read, wrote:
Water is the big one, the discussion here is about the impact of a GHG between two bodies or not it does not confine itself to CO2.
Are we seeing a sensitivity in people to a well discussed point at both a mathematical level and observational level.
Good article and worth the points made.
In some ways it’s a mistake to compare Venus Earth and Mars, the differences are greater than their similarities.
Venus/Earth similar size but vastly different atmospheres, rotational period, direction of rotation, magnetic field.
Venus/Mars have very little in common other than their atmospheres are predominantly carbon dioxide but the partial pressure of CO2 is massively different.
Earth/Mars have similar rotational periods and similar axial tilts but that is all.
On Venus the atmospheric pressure has a more significant impact than on Earth. The rotational period and direction likewise. Finally Venus is 30% closer to the sun than the Earth is.
Do greenhouses work because of the greenhouse effect, or is it the lack of air movement? If it’s a sunny but windy day, it is warmer if you sit behind a windbreak.
While Venus receives twice as much solar radiation at the top of its atmosphere than Earth, our planet gets a lot more at its surface, due to Venus’ high albedo and absorption in its dense air. Since only about ten percent of solar radiation reached Venus’ surface, versus about 69% of Earth’s, our surface gets about 3.45 times as much insolation as Venus.
Our sister planet is hot because it rotates so slowly and has such a think atmosphere.
Anyone that has looked at Venus through a telescope and understands what albedo is can see that a tremendous amount of solar energy is being reflected by it’s atmosphere. You never see the surface of the plant. It’s just a bright white ball and the second brightest object in the night sky after the moon when the planet is “up”. Really a boring telescope subject.
The fact that the Venusian day is longer than it’s year is overlooked as is the fact that it’s rotation is retrograde. Comparisons with other bodies in the solar system are effectively meaningless.
They don’t have similar amounts of CO2, they have similar percentages of CO2. Venus has an atmosphere that has 92 times more pressure than Earth’s atmosphere. Mars has an atmosphere that’s less than 1% of the pressure as Earth’s.
There is actually more N2 on Venus than on Earth….
since we only talk about % of CO2, thats a valid comparision … nobody cares about the “amount” of CO2 …
I care about the “amount” of CO2. With regard to greenhouse effects, I would expect that to be far more important than the % of CO2.
Yes, to certain (I would think negligible) extent in the Earth’s atmosphere.
a) At 400ppm there are about 2500 other gas molecules for each one of the CO2 molecules.
b) I’ll assume that CO2 would absorb more energy than the other gases, thermal energy is expression of the kinetic energy of molecules Brownian motion. After few collisions with other gas molecules CO2 would soon lose it’s energy excess.
c) Let’s assume CO2 molecule absorbs 100% more energy than any other gas present. It can transfer that energy after one or 2500 (or anything in between) collisions. Either way total amount of energy in any volume (after energy equalization) would be increased by 100%/2500 = 0.04%
d) The average surface temperature of the planet at 288 degrees kelvin (15 Celsius or 59 Fahrenheit).
e) That would mean that the 100% more effective CO2 at the 400ppm concentration would increase global temperature (∆T) by 0.11C.
f) If CO2 effectiveness is n x 100% than global temperature would increase by n x 0.11C
I have no idea, how effective is CO2 in relation to the other gasses, but if you do then you might calculate ∆T, i.e. if the above makes any sense.
For other planets the same principle may apply taking into account the planet’s CO2 concentration and its average ‘global’ temperature.
Jeremy, you’re going to need to put your big boy pants on and take a rush course in reading comprehension if you want to make any kind of cogent argument on this site. Not that you even attempted to.
Dr. Wentworth made the key statement on this to actually attempt to negate bogus conflations:
“Note that being certain about the GHE being real is different than being certain about Anthropogenic Global Warming (AGW), the hypothesis that human-caused increases in the concentrations of “greenhouse gases” in the atmosphere are causing highly problematic changes in the Earth’s climate.
AGW is a far more complex phenomenon than the GHE alone. One can be skeptical about AGW while totally accepting the reality of the GHE.”
The CO2 AGW greenhouse gas failed conjecture to-date starts above 280ppm, and it’s on a background of water vapor, sun’s activity plus or minus, cloud cover, convection, Beer-Lambert Law, etc. etc.
… but do stick around here, because if anything happens that makes CO2’s empirically measured effect, using the scientific null hypothesis, something that is indistinguishable from zero, this site is likely to be the first and best place you will be able to read about it.
Classic WUWT rebuttal … bravo!
Venus & Mars have similar proportions of CO2 in their respective atmospheres not similar amounts. And their surface atmospheric pressures are dramatically different.
Pressure on Mars: 0.095psi
Pressure on Venus: 1350psi
Temperature increases as pressure increases.
Temperature increases as pressure is increased. When pressure is constant, temperature does not increase.
Very good Mark. Gases undergoing adiabatic pressurization heat up. Big enough delta P can cause enough delta T cause auto ignition of some hydrocarbons in air.
However pressures are never constant for long. The depth of the atmosphere is under constant change, from heating and cooling, continually altering the pressure. Just watch any barometer.
Atmospheric pressures are never a constant everywhere. The must decrease with altitude.
I can’t work out if you’re agreeing with me or trying to be sarcastic. Your response makes no sense.
He is taking the possition of one in 100% circular reasoning.
A clear effect of “must support Bob’s ‘flatearth’ circular reasoning”.
And GHE does not increase the pressure of the Earth’s atmosphere.
The physical variation of the atmosphere is thermally driven by the oceans thermal variation and it’s coupling exchange with atmosphere.
The GHGs and the GHE simply features, that vary in accordance.
Extrapolating in the proposition of the “E” @ur momisugly GHE by making it sound like a real physical effect on the Earth’s surface temp. and therefor climate,
is not any different than a flatearth argument these days, according to the observed reality.
Initial condition is initial, not an outcome condition.
Else, circular reasoning will rule the day, as it actually does clearly in the whole subject of climastrology… but not only.
The triangle of M. Cycles(effect), GHE and AGW is the very base and core of the “climate science”.
And it stands invalid, as invalidated by reality.
So whatever Bob claims in this article, is/are invalid… as far as climate and Earth’s surface temp is concerned.
GHE is simply a physical feature with no saying or potential versus climate or Earth’s surface temps.
cheers
The difference is the thickness in atmosphere as pressure heats gasses that are compressed. Examples that use compression to heat gases to high temperature. diesel engines, jet engine and even heat pumps.
More accurately the pressure difference in an atmosphere results in a temperature difference. The pressure difference is a more important cause of the temperature difference than the number of GHE molecules in the atmosphere.
Compression of gases produces transient one-time heating, not ongoing heating in steady-state.
Steady-state is what is relevant to determining the temperature of an atmosphere.
You are correct that it is a steady state siruation and Stephen misstates the situation by saying the pressure “heats” the gases. In the dynamic steady state of an atmosphere the pressure maintains a temperature differential causing the effective radiative surface to be above the actual surface and allowing the surface to be warmer than it would be in the absence of an atmosphere.
It’s true that one way one can think about things is that there is an “effective radiative surface” and that the lapse rate means that the surface will be warmer than the effective radiative surface.
That doesn’t, however, mean that one can dismiss the importance of radiative gases in the atmosphere.
The effective radiative surface would always be at the actual surface, in the absence of radiative gases.
And, increasing the concentration of radiative gases will tend to raise the altitude of the effective radiative surface because it increases the LW optical opacity of the upper atmosphere.
Thinking about this …
I’m not claiming that “one can dismiss the importance of radiative gases in the atmosphere.” Still not convinced that “The effective radiative surface would always be at the actual surface, in the absence of radiative gases.”
I’m trying to visaulize the behavior of a non-radiative gas atmosphere in terms of heat flux or energy transfer. A pure nitrogen atmosphere will clearly have a steady state temperature near the surface equal to that of the solid surface but your statement implies it might be absolute zero. Some energy must be transferred to the atmosphere through conduction. The other implication is that the surface will be colder with a nitrogen atmosphere than it would be with no atmosphere. That’s definitely counter-intuitive and needs some thought for me to accept.
The effective radiative surface real ought to be in a place where radiation is possible. If there are no radiative gases, then the actual surface is the only place where radiation is possible.
Why would you think the surface temperature would be anywhere near absolute zero?
I would expect the average surface temperature to be somewhat lower than Tₑ (close if heat storage and lateral heat transfer are efficient, and further away from Tₑ if these are not efficient), which shouldn’t be anywhere near absolute zero.
Some energy must be transferred to the atmosphere through conduction.
Yes, some energy would be transferred to the air through conduction.
There would actually still be some convection. It’s just that the convection wouldn’t ultimately be delivering energy into the upper troposphere. Instead, it would be transferring heat from the surface near the equator to the surface near the poles.
This would somewhat equalize surface temperatures across latitudes. As a result, the average surface temperature would get somewhat closer to Tₑ, while still being less than Tₑ.
In steady-state, I don’t think so. Once the surface has warmed the atmosphere to its steady-state temperature, the atmosphere would no longer cool the surface.
The only effect would be that the atmosphere would transfer heat from low latitudes to high latitudes. This would reduce temperature variations, and this would, as I said, lead to a net increase in the average surface temperature. But, that increase would be limited to not raising the average temperature above Tₑ.
So, a planet with a pure nitrogen atmosphere would be somewhat warmer than a planet with no atmosphere (unless the planet with no atmosphere still managed to have ocean currents to distribute heat between latitudes).
Near absolute zero because if only GH gases can absorb the energy then the energy will escape to space without warming the atmosphere at all. But of course that doesn’t happen because of conductive contact with the surface.
A non-GH atmosphere would transfer the heat obtained through conduction to the upper atmosphere since the gas warmed at the surface rises. What in then world happens to that heat energy?? Simple answer, and you know it: it escapes into space in the form of radiation. It is simply not true that non-GH gases don’t emit radiation. They still do in a Plank’s distribution of frequencies. GH gases simply have the characteristic of absorbing and emitting energy at specific frequencies. In fact all gases have that property. So called greenhouse gases simply absorb and emit in the portions of the Plank distribution which are most predominant at the temperature of then Earth.
The incoming radiation flux does not determine the surface temperature alone. That is determined by how fast the energy can be shed back to space or the surrounding atmosphere. As your essay states, In the absence of an atmosphere that is essentially defined by S-B.
With a non-GH atmosphere (one which doesn’t absorb in any predominant portion of the Plank distribution for the temperature) all the radiative portion of the surface emission escapes to space without warming the atmosphere. But some of the surface energy goes into conductive warming of the atmosphere: Fluxin = RadiativeOut + ConductiveOut. The implication of that is that the Radiative flux (FluxIn – ConductiveOut) is less than that required for the non-atmospheric case where RadiativeOut = Fluxin. Hence the surface is cooler with the non-GH atmosphere, counterintuitive.
“Simple answer, and you know it: it escapes into space in the form of radiation. It is simply not true that non-GH gases don’t emit radiation. They still do in a Plank’s distribution of frequencies. GH gases simply have the characteristic of absorbing and emitting energy at specific frequencies.”
That is not really a good description of what is happening.
Planck’s Law gives the maximum possible radiation at any given frequency at a specified temperature. For temperatures important for earth (~ 200 – 320 K):
“(Ie N2 has no strong emission bands in the relevant IR range.)”
Why does N2 have to radiate to space at IR? Why can’t it radiate at near IR or some other frequency?
The emission/absorption of gases are changing in mixtures and due to collisions between molecules.
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2012GL051409
https://www.nature.com/articles/2091341a0
https://link.springer.com/chapter/10.1007/978-94-010-0025-3_16
A way nitrogen and oxygen are capable of working as “greenhouse gases”.
Even if warming of the atmosphere wouldn’t be very efficient, neither would cooling of the atmosphere be efficient. Even if it takes time, the atmosphere should equilibrate with the surface temperature
While all gases radiate, the rate at which they radiate can be vastly different. Do you know of any experimental measurements of the emissivity of nitrogen and oxygen?
I have an impression that it is negligible compared to that of GHGs.
I believe that the primary heat loss mechanism would be via atmospheric circulation bringing the air back in contact with a colder portion of the surface.
I don’t know how fast atmospheric circulation would happen, or how efficient it would be, but it would happen, and would provide cooling to offset the warming from lower latitudes.
Sure.
Um, no.
There is some coupling strength that the gas has to the black-body spectrum characteristic of a particular temperature.
That coupling strength is going to determine both the rate it which the gas can radiate to space and the rate at which it can absorb energy radiated by the surface. There is no mechanism that would allow it to preferentially cool without causing surface warming.
So, non-GHG’s will act like very weak, very ineffective GHGs. To the extent that extremely dilute GHGs could warm the surface, non-GHGs could too.
But, I suspect that, overall, both the radiative cooling and warming effects from the non-GHGs will be negligible.
GEOPHYSICAL RESEARCH LETTERS, VOL. 39, L10706, doi:10.1029/2012GL051409, 2012
The natural greenhouse effect of atmospheric oxygen (O2) and nitrogen (N2)
M. Höpfner,1 M. Milz,2 S. Buehler,2 J. Orphal,1 and G. Stiller1
Received 20 February 2012; revised 23 April 2012; accepted 23 April 2012; published 24 May 20
Thanks. And here’s a link to that reference.
Note that, on a per molecule basis, the results of this reference indicate that N₂ and O₂ are, respectively, a factor of 3e-6 and 7e-6 less effective at absorbing/radiating LW radiation than CO₂. That’s well over a hundred thousand times less effective.
That is, of course, partially compensated for by N₂ and O₂ being so much more abundant than CO₂. Even so, the net effects of N₂ and O₂ are 0.6% and 0.4% as large as the impact of CO₂.
So, the radiative effects of N₂ and O₂ are quite a bit smaller than the effects of the so-called greenhouse gases, but they do exist, and are not entirely negligible.
“I’m trying to visaulize the behavior of a non-radiative gas atmosphere in terms of heat flux or energy transfer.”
Earth atmosphere is 99% pure in terms of non-radiative gases.
Though one could call the non-radiative gas as being radiative gases. Ozone does not absorb longwave IR but it’s called a “greenhouse gas”. Though Ozone, Oxygen, Nitrogen and Argon does absorb small amounts of Longwave IR. And everything in the sky absorbs some sunlight.
And there also more than millions of tons of dust in atmosphere.
Reaching absolute purity is kind of hard- especially when people don’t even bother defining things well. Even look at it much, really, such as how much salt particles are there. Oh, it’s claimed:
” According to the IPCC report, the total sea salt flux from ocean to atmosphere is ~3300 teragrams (Tg) per year.”
or 3.3 billion tonnes
Purity is difficult in this universe. But in our Ice Age we don’t much greenhouse gases in Earth’s atmosphere. But we apparently have more as compared to the colder glacial periods.
Maybe that is your answer find coldest times in recent glaciation period, globally it should have least amount non-radiatives gases, so maybe closer to 99.9% pure.
And whatever, caused it to become warmer, wasn’t related to amount greenhouse gases.
Wherever there is an atmosphere there seems to be a lapse rate. Independent of atmosphere composition.
It would therefore be surprising that the presence/absence of radiative gases has anything to do with it.
No, pressure is in a steady state (900hpa – 1050hpa) so is the heating it produces. Compression is air particles forced closer together colliding in a steady state. Fluctuations happen close to the surface but cooling with height is the adiabatic lapse rate. “air parcel changes in response to the compression or expansion associated with elevation change”
Consider the Ideal Gas Law, which says P = ρ T (R / M) (where M is the average molar weight of the gas).
It is possible for a gas at a given pressure, P, to have absolutely any temperature, T. All that needs to happen is for the density, ρ, to adjust appropriately; it automatically does exactly that.
Pressure does not determine temperature, nor does it produce heating in steady state. Pressure-related heating only happens when you change the pressure of a gas.
In the atmosphere, an equal mass of air is moving upwards and downward. The cooling and heating effects of these air movements balance so that there is not any net generation of energy. (Otherwise, you’d be postulating a magical source of energy-from-nothing.)
This establishes an adiabatic lapse rate, but does not establish any absolute temperature level. Make everything 10 degrees warmer or colder and it wouldn’t necessarily make any difference.
Isn’t gravity considered to be one of the potential sources of a perpetual motion machine?
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All of these examples involve doing work to increase pressure. It is that work which generates heat. Static pressure does not dictate temperature. Consider a pressure cylinder containing oxygen or another gas under very high pressure. Left outdoors in winter it may be very cold indeed.
It’s not a “static” system but a very dynamic one fueled by radiation from the sun. I liken it more to the operation of a refrigerator than the examples. Energy from the sun heats the ground and the lower atmosphere which carries the thermal energy to the upper atmosphere where the reduced pressure causes it to cool.
Jim,
Unless you uphold and take AGW as true, your point can’t stand as valid.
As otherwise the way of climate in this Earth of ours invalidates your point, regardless of the way that it may be massaged.
You can’t have it both ways.
cheers
No, has nothing to do with AGW. In fact most of my posts in this thread are an a attempt to show that certain physical properties of the atmosphere other than greenhouse gases could be responsible for the observed state of the Earth’s atmosphere. My post is simply to acknowledge the dynamic existence of weather (not AGW) and it’s causes.
Jim, please do consider this;
By your own means of assessment, would you or not consider yourself as a Luke warmer?
All spirit and meaning of this blog post of Bob is, and stands,
as a premise call to Lukes… like EW.
So tell me if you can,
the grounds you stand on.
Are you or not a Luke?
cheers
Depends on what you consider to be a “lukewarmer”. here’s a Q and A to myself:
Q: is the earth warming?
A: it appears so be doing so but that may be because we are in the warming phase of a natural cycle.
Q: is the warming catastrophic or apocalyptic?
A: No, it is gradual and beneficial
Q: Is CO2 influencing the temperature?
A: No evidence supports such a conclusion and observations compared to hypotheses derived from such an assumption show it to be wrong.
Q: So you deny GHE effects?
A: No. There is scientific evidence that GHE does exist. BUT: I have seen no evidence that GHE is the main controller of or even reason for the Earth’s temperature.
Q: Why do we need any explanation for the Earth’s temperature.
A: Because the temperature of the earth would be much lower than it actually is were it not for the atmosphere. There are definitely characteristics of an atmosphere that help retain heat at the Earth’s surface.
So, I ask you. Am I a “Luke”?
Let me put it straight forward.
A Luke these days consists as a very annoying “prostitute”.
Are you one or not?
Still Mann, the ugly one does not consist to be either a whore or prostitute.
It simply consist to be a pimp.
Bob is taking the approach here of a soft and sweet ‘pimp’.
Telling all ‘whores’ there to either shut up and get on with the business, or else go elsewhere and try
the luck.
It is harsh, yes, but still fair in the end of the day.
As fair as ‘death’.
cheers
Rich,
It is a relationship. The ideal gas law is PV=nRT. If the temperature goes down then PV must change also. Since you are talking about a constant volume (pressure cylinder) the pressure will decrease also.
That means the pressure is not static. If you repressurize the tank to the original “high pressure” the temperature will rise to the same temperature. If it doesn’t, you don’t have an ideal gas.
It is a good question, because even though Mars has only a small atmosphere, nonetheless, on a molecular basis (if you were to count the number of CO2 molecules present), Mars has an order of magnitude more CO2 molecules in its atmosphere, than are contained in Earth’s atmosphere.
Further the tempreture on Mars and in its atmosphere correspond far closer to the the 3 apsorption bands of the CO2 molecule, such that CO2 is a far more efective radiative gas in the conditions present in the Martian system, when compared to those existing on Earth.
If there is a GHE on Venus it operates very differently to the argued for GHE on Earth, since the Russian landers measured incoming solar irradiance at the surface of Venus, relatively near to the equator, and it was about 3 to 5 w/m2. Compare that to the solar irradiance, at noon clear sky at the equator, of Eerth which is close to about 1200 w/m2.
Solar irradiance received at the surface of Venus does not (significantly) warm the surface of Venus, because there is all but no solar irradiance reaching the surface, thus one does not get the argument that SWIR in warms the surface, and then the warmed surface reradiates LWIS out, which LWIR is then “trapped” leading to the GHE warming.
I once calculated Mars has about 4000 moles/m² of CO₂ while Earth has about 140 moles/m². (Venus has 2.3e7 moles/m² of CO₂. Earth has about 860 moles/m² of water vapor.) So, I agree with this assertion.
However, before concluding this in any way disproves the GHE, I’d want to see a calculation of the predicted warming effect of Mars’s atmosphere and compare it with observations. The math doesn’t always work out the way that people intuitively expect that it should.
Whether or not solar irradiance reaches the surface is not actually important to the GHE.
If you look at the analysis in my essay, you’ll see that it doesn’t make any assumptions at all about where external energy enters the system.
If you’ve seen explanations of the GHE that talk about sunlight being absorbed by the surface of the Earth, that’s just because it’s a simple way of trying to explain things, not because it’s actually in any way essential to the effect being discussed.
The concentration of GHGs is only one important factor. The “effective radiating height” is also important for explaining the differences between Venus, Earth, and Mars.
Consider 3 identical planets that each have an atmosphere of 99% N2, 1% CO2. But the surface pressures of the three are 100 bar, 1 bar, and 0.01 Atm. The first planet will have the highest surface temperature, because the effective radiating height is the highest; the last planet will have the lowest temperature, because the effective radiating height will be pretty close to the surface.
(And of course, the distance from the sun, concentration of CO2, and presence of other GHG’s are important.)
You do get that the first planet has 10,000 times as much CO₂ as the third? That’s likely to as important as the issue of effective radiating height. Having the same percent concentration does not make the amount of GHG present comparable.
Venus is a lot closer to the Sun, and it has an Bond albedo of about 0.75.
That means 25% of incident solar radiation does enter the atmosphere of Venus, whether or not it makes it to the surface.
And so it is heating it up.
If I am under a thick pile of blankets, and I have a heating pad under there with me, does it matter very much, if at all, if the pad is under me, or above me, or even between the bottom blanket and the one just above it?
It probably matters a little if the pad is above one of the thick stack of blankets instead of under than all, but it is still warming me up plenty, and that heat is very slow to escape through all them blankies.
“Similar amounts”? I don’t think so, Tim. The atmosphere of Venus is many times the density of Earth’s, which is many times the density of Mars’. Not to mention that Mars is more than twice as far from the Sun. Apples and Oranges, with the apples in the fridge and the oranges in the oven.
Plus the apples do not have any water vapor, I mean watermelons, in that fridge with them.
And them watermelons are yuuuuge!
See how CO2 compares to H2O:
Now, Venus is listed as having only a small fraction of the % of water vapor that Earth has.
Earth overall is listed as 0.40% H2O in the air.
Venus is listed as 0.002%
20 parts per million.
But Venus also has 150 ppm of sulfur dioxide.
And Venus’ atmosphere is something like 90 times as dense.
So that 20ppm of H2O, and 150ppm of SO2, translates into 90 times as many actual molecules in the air column on Venus as a similar concentration would have on Earth.
So I am gonna go out on a limb here and assert that 20 ppm in a column of air that is 90x as dense, provides plenty enough molecules to close off the wavelengths that H2O blocks.
And then there is a huge amount of sulfur dioxide, which probably exists as SO2 and well as the thick clouds of sulfuric acid that blanket the planet.
Between those two, could that be what closes off the rest of any possible atmospheric windows left between the CO2 and the H2O absorption bands?
What matters is the windows, to a large extent.
Does Venus have any?
What about Mars, with CO2 and little else?
Big gaps between CO2 bands are filled with by water of Earth.
Venus has about half as much water vapor as Earth, and it is likely to be very evenly distributed.
I for one am not losing any sleep over the fact that Mars is cold and Venus is hot as Hell.
No one ever proved anything by selective attention to details.
If you have to lie about the other person’s argument, then you have admitted up front that you know you can’t refute the argument.
A grand total of nobody has claimed that CO2 is the only thing that drives temperature.
Find another red herring to fry.
Two reasons. One is the distance from the sun. The other is the density of their atmospheres. If I remember correctly, the atmosphere of Venus is about 90 times the density of the Earth’s atmosphere, which would make it about 9000 times the density of the Martian atmosphere.
The author needs to go back to the Moeller paper that first proved that CO2 had warming properties. His abstract said specifically, CO2 is such a weak greenhouse gas that it can only be measured in a “completely DRY atmosphere”. If there is any moisture in the atmosphere, you cannot see the effect of the CO2 at all. Moisture is the greenhouse gas that keeps the Earth habitable, and is completely beyond control of stupid humans.
Moisture cools the tropics (not people as our sweat can’t evaporate in saturated air) and warms in places in higher latitudes(where water in most prevalent, Western Europe). Water keeps the earth habitable, not air borne moisture. CO2 is 25 / 68000 joules.
That would be right, if and only if water and CO2 absorb in the same bands. But some lines of absorption of CO2 are in bands where water vapor is not active. Thus both are additive. Can be seen in the absorption bands if you double CO2:
http://climatemodels.uchicago.edu/modtran/
For the most part, there is very little energy available in the bands where CO2 absorbs and water does not.
I doubt that that is true Ferdinand at current CO2 levels, and it would be a super inexpensive experiment (on a scale of things) with which to find out the answer. So why don’t the climate crackpots do the experiment. I think I know the answer.
Two more things: First, pressure broadening works both ways. Secondly, the original ModTran paper relied on modeling to get those teeny weeny edges right (allegedly) and the authors weren’t shy about reporting this because, as above, nobody built the equipment to do the f-kin experiment, as far as I know, even since then. If I’m wrong, please someone correct me. I could build the equipment for under a $Million. I do that kinda stuff.
…. and then lastly, I want to thank the person who sent me the link to the original ModTran paper 8 or 10 years ago. It was you Ferdinand, thanks again.
Water freezes at 0°C so at higher latitudes and has no energy below -6°C. And obtain heat from conduction (tropics to mid-latitudes) prior to evaporation. Absorption bands are outside the window 8-14µm(tropics to poles). 8µm = 976 watts emitted heat, 14µm = 104 watts of heat. This window is transparent to outgoing infrared radiation. CO2 and water vapor have no absorption in this band. The 15µm CO2 band is for mesosphere climate (-80°C to -100°C) not surface climate.
isn’t there really just one small small band where CO2 absorbs and water does not? Doesn’t CO2 absorb only a few very narrow bands while the opposite is true of water?
It’s not excellent if its wrong.
So prove it wrong.
I have!. Read what I have posted and then ask questions. Start with the sun at zenith 1kw. Then every latitude from 0° to 90° substract 11.1 watts. You will find at 45° is 501 watts. Insulation 390 watts SH, 325 NH (358 watts global), less at certain time of day. How much is reflected. What is the greenhouse effect? energy retained. Answer zero.
Maybe you mean insolation?
Isn’t it the case that if there is no atmosphere, then the top of the atmosphere is at the same physical point as the surface of the planet, so naturally Ts = Tt? No heavy math required.
Sure, but the discussion was not about there being no atmosphere. It was about an atmosphere with no components that absorb or reflect LW radiation.
I’m only making one comment here, as this one will probably blow up later today – if a moderator has time, they should replace the U+209b and U+209c codes with subscript tags (i.e., Ms and Mt). These don’t show up properly on many browsers, even my fully updated Foxfire.
Sigh. Foolish software. Subscript tags work fine in the test page. Work fine when writing the comment. DON’T work when the comment is actually posted!
I don’t have a fix in mind for this one, but it really should be working for a science site.
It is WordPress. Over at Judith’s when I posted a long very mathy comment on Monckton’s ‘irreducibly simple’ equation, she got so frustrated that she added the math stuff as a separate pdf ‘image’ that WordPress could not screw up.
Yes, the Greenhouse Effect is real. But then convection and the water cycle intervene to cancel it.
Given a system variable modification (increase in C02), there is a some lag before equalization. That is the warming (or cooling …).
Whether or not it (the lag) is in any way significant has not been determined
( … through this post or otherwise).
The results of the lag are likely and reasonably described as insignificant or incidental with respect what is accepted as weather. If it wasn’t insignificant, and it caused an amplification of the subject variable, the earth climate would be very very very unstable and easily altered.
You hit on something there — adding more greenhouse gases to a sealed test tube shows an increase in temperature (when compared to a control test tube without the added GHGs).
But the earth is not a beaker or test tube. The components of the climate system work together. Our atmosphere isn’t sealed.
To experience the Greenhouse Effect, you need a greenhouse.
Exactly.
Evaporation and water vapor turn from a positive feed-back to a negative feed-back at ocean temperatures of the order of 20 C or so, and by 30 C become an absolute limiting factor to increases in ocean temperature (as has been discussed in many blogs on this site in recent days) and atmospheric temperatures.
The clearly don’t entirely cancel it, or the Earth would be 26℃ colder than it is.
Yes, the question of how much additional increases in greenhouse gases will increase temperatures is a complicated open question.
But, it would be misleading to suggest that the GHE is entirely canceled out by other processes.
The “GHE” (abiliity of certain gasses to absorb and re-emit) is not entirely canceled out by other processes.
In the subject system, adding such a small amount of certain gasses, that absorb and re-emit, will likely fall within the range of self correction, and a portion of theoretical impact is canceled out.
On Earth, the clear evidence (based on my analysis) is that at least 26℃ of warming related to GHG’s (including water) was not cancelled out.
This does not, however, offer any clear indication about the extent to which the effects of marginal increases in GHG concentrations will or won’t be cancelled out.
Personally, I think of it as being overwhelmed by other factors, rather than cancelled out.
Almost completely cancel it out.
No negative feedback can ever completely cancel out the original signal.
Take a look at open channel hydraulics as the analogy, rather than electric circuits.
The GHE is real, and vital to our survival, mostly due to good old H2O, the dominant GHG. It is not thankfully cancelled by convection. It may well be that the tiny additional GHE of our fossil fuel CO2 emissions is cancelled by emergent phenomena, but even if that is not the case, it is fairly irrelevant since it’s such a mild beneficial warming, mostly raising night-time and winter lows in higher latitudes.
if there is no temperature rise there is no intervention.
this is a discussion about the GHE being real and it does heat the atmosphere from there its about feedback positive or negative but the temperature is higher as a result of the GHE.
You need to prove that GHE is canceled by convection and the water cycle. I am of the mind they modify some of the operations, but that they can’t cancel the mathematically proven GHE.
At top of troposphere, water content is less than 10 ppm, and C02 content is 400 ppm. The higher level of CO2 at present versus 150 years ago absorbs and reradiates more heat both up and down. Stratosphere gets colder and surface gets warmer. At some wavelengths, there are many reabsorption layers between stratosphere and ground level but not so many to outer space. Net result is some warming at surface…about 1 degree per first 100 ppm of additional CO2, 1/2 degree for second hundred ppm, 1/4 degree for third hundred ppm, and so on…or some fraction or multiple of a degree per additional 100 ppm of CO2 depending on who pays your salary.
Anyway, convection and water cycle have little to do with it at those altitudes.
the hydrosphere is anything but spherical I assume; at the Poles at 100m above sea level the air is relatively H20 scarce and at the tropics the H20 extends to the top of the troposphere as you describe : the shape of the water vapour rich atmosphere is a ?prolate spheroid (not sure of exact name for that one) – as the temperature profile of a region over sea changes its water vapour profile expands and contracts as a negative feedback loop, where water vapour becomes a means of more rapid bulk transport of energy to space – is my imagined feedback loop that maintains earths biosphere, except when clouds cover and reflect energy to space for long periods making snowball earth
An excellent post. Thank you
Not really, anyone that starts by telling us he is as certain of an empirical statement as a tautology has to be suspect.
More accurately, I am as certain of the GHE as I am of the S-B Law. The relationship between these is a tautology.
I don’t get the impression there are that many of us skeptics that deny the GHE is a factor. It just seems that the relatively few that do are loud and prolific posters. And though I appreciate your effort, I doubt it will persuade your target audience. Not because you have not presented well, but simply because of the recalcitrant nature of those you are trying to persuade.
The only arguments I recall are those that try to explain that real greenhouses are not proper analogies.
Real greenhouse work by inhibiting convective cooling. The GHE works by inhibiting radiative cooling. And the major GHG is water vapor, not CO2, hence my focus in previous comments and posts on water vapor feedback
An interesting description, but there is no mechanism that “inhibits” radiative cooling analogous to a physical greenhouse. Clouds don’t suffice.
That’s what he said.
No, he said the greenhouse effect works by inhibiting radiative cooling. That is not even wrong. it works by gasses radiating energy downward. No mechanism inhibits that.
You are missing that there are two distinct perspectives for talking about radiation, both valid.
In one perspective, one looks at the energy flux associated with radiation flowing in each direction. In that framework, one might separately measure “upwelling LW radiation” and “downwelling LW radiation.” Within that perspective, it’s noted that GHGs increase the amount of downwelling LW radiation.
In another perspective, one looks at the “radiative heat transfer”, which is the net energy transfer one computes when subtracting the flows in the two directions. Within this perspective, it’s noted that GHGs decrease the net radiative heat transfer rate from the surface to the atmosphere.
The reduction in the rate of radiative heat transfer is what is meant by saying that GHGs “inhibit radiative cooling.”
Both descriptions are entirely valid. The description in terms of “downwelling radiation” tends to elicit resistance from some people, while people tend to not “get” the description in terms of reduced “radiative heat transfer.”
It’s an uphill slog, either way, to get to a point of people understanding each other.
Shouldn’t the TOA radiation actually be higher than the Surface radiation, because a great deal of Surface Heat energy is removed from the surface by other means than radiation?
When energy gets in to the troposphere the only way to space is Radiation, but that is not how it gets there in the first place.
Surface radiation needs to be higher than TOA radiation because the surface is, on average, the hottest part of the system and radiation is emitted in proportion to T⁴.
Measurements confirm that surface radiation is higher than TOA radiation.
* * *
It helps to distinguish between radiation and radiative heat transfer.
Your argument is correct, with respect to radiative heat transfer. The radiative heat transfer away from the surface is less than the radiative energy transfer to space at TOA.
However, radiative heat transfer is the net effect after you subtract downwelling LW radiation from upwelling LW radiation.
So, it’s entirely consistent that radiative heat transfer from the surface is less than at TOA, but upwelling radiation flux is greater than at TOA.
“Surface radiation needs to be higher than TOA radiation because the surface is, on average, the hottest part of the system and radiation is emitted in proportion to T⁴.”
Please expand your system to be 30 miles above ‘TOA’ and restate ….
I’m afraid I’m not following what you’re talking about.
My understanding is that TOA (top-of-atmosphere) refers to what is seen at an altitude high enough that going higher results in to additional significant changes in the measured upwelling radiation.
If that interpretation of the term is correct, then going “30 miles above ‘TOA’” would make no difference.
Am I missing something?
Same radiation … yes.
You have two variables that you are using to make your point.
I’m afraid I still have no idea what point you are trying to make.
If the system extends to 130 km, then where is the hottest part of the system?
“Surface radiation needs to be higher than TOA radiation because the surface is, on average, the hottest part of the system and radiation is emitted in proportion to T⁴.”
I guess I should have clarified that radiation emitted is also proportional to density. The surface is the warmest part of the system where there is a high enough density to matter.
While the temperature is high in the thermosphere, it’s utterly irrelevant to the Earth’s thermodynamics. There isn’t enough gas there to matter.
I still can keep up with the logic in the above quote. Regardless of the density of the gasses.
Can we say that “the radiation at bottom of the Mesophere needs to be lower than the radiation at the top of the Mesopherre because the bottom is, on average, hotter”?
No. But we can say that “the radiation flux at the bottom of the Mesophere needs to be higher than the radiation flux at the top of the Mesopherr because the bottom is, on average, both hotter and denser”?
so, not just Temp and Radiation flux … a third parameter of density.
If colder but denser (stratosphere variation) can the radiation flux comparison with temperature be stated in a manner that means anything?
And with relatively constant temp across the Stratopause; radiation flux at the bottom of the Stratopause “needs” to be (lower?) than the radiation flux at the top of the Stratopause because …
??temperature is the same and the density varies??
For any complicated situation, one needs to sit down and do the math, instead of making generalized arguments.
“Colder and denser” is that sort of “complicated situation.”
Even figuring out radiation fluxes within the Stratopause isn’t simple. It’s not just about what’s going on inside the Stratopause, it’s also about what is going on above and below. Air below is warmer and denser. Air above is warmer and less dense. Is the Stratopause thick enough to be optically dense, or is it nearly transparent? All those details are likely to matter.
Your statement:
“Surface radiation needs to be higher than TOA radiation because the surface is, on average, the hottest part of the system and radiation is emitted in proportion to T⁴.”
After a lot of back and forth crap (mostly mine …), we get to the following:
“For any complicated situation, one needs to sit down and do the math, instead of making generalized arguments.”
Your initial statement is a generalized argument. I didn’t see any math or discussion that shows which variables are reasonably neglected.
True. My original statement did, however, relate to a less complicated comparison than the ones that subsequently entered this discussion.
I was holding the math in my head, and thinking about what could be asserted with some degree of safety.
There’s always a dilemma:
So, it can be challenging to find a way to connect and have a quality discussion about how things work.
* * *
If you’re interested, here is a bit of mathematical unpacking of the argument I was making…
Surface radiation is emitted at a rate 𝜀σT⁴.
Atmospheric radiation is emitted as 𝜀ₓρH⋅σT⁴ where ρ is density, H is the thickness of a horizontal layer of the atmosphere, and 𝜀ₓ is emissivity relative to gas mass per unit area.
So, it’s a little tricky to make a direct comparison between surface and atmospheric emissions. However, the temperature of the surface is higher, and 𝜀ₓρH is generally smaller than 𝜀 for the surface, even for fairly substantial layer thicknesses H. So, surface emissions are likely to be higher than for any layer of the atmosphere.
It is easier to compare gas radiant emissions low in the atmosphere and high in the atmosphere. In that case, wherever 𝜀ₓ⋅ρ⋅T⁴ is higher, spontaneous emissions will be higher. Each of these factors is higher low in the troposphere than high in the troposphere. (𝜀ₓ will be higher where the mixing ratio of water vapor to air is higher, and mixing ratio can be higher where temperature is higher.) So, all factors line up to ensure that atmospheric radiant emissions will be higher lower in the troposphere.
This discussion, however, leaves out a few effects.
The big thing it leaves out is that the total radiant flux in any portion of the atmosphere is a function of both what is being emitted locally, and what has gotten there from other altitudes without having been absorbed. I don’t currently have a hand-waving argument to make that I trust would tell us what that total radiant flux is at different altitudes. (I might or might not be able to come up with such an argument with further thought.)
Low in the atmosphere, I’m pretty sure it works out that total radiant flux decreases as one ascends, just as spontaneous emission decreases (though I’d be more confident if I worked through more math). Up in the tropopause, there are higher temperatures in both directions, and increasing ozone concentrations above, but decreasing atmospheric density, and all that renders me less certain about how the total fluxes are likely to vary.
Another thing the above discussion omits is stimulated emission (as opposed to spontaneous emission). I think that stimulated emission is usually a lesser effect, but I haven’t done specific calculations to back up that idea.
A slight clarification: the formula 𝜀ₓρH for emissivity of a gas layer is valid only for thin gas layers, where 𝜀ₓρH is much less than 1. As the layer thickness increases, this linear relationship breaks down, as total emissivity will remain less than 1. Also, while one could express emissivity relative to density, gas emissivities are more typically expressed relative to pressure, at a specified temperature.
Even for a thick layer of atmosphere, the net emissivity will remain considerably less than 1 because the mixed gases cannot emit at all wavelengths.
So, in comparing emissions from a warm surface (with emissivity usually well in excess of 0.85) to spontaneous emissions from a cooler atmosphere, the emissions from the surface will always be larger.
The author is the recalcitrant one with his ignorant and condescending remarks about flat earthers and math deniers. Typical ignorant rant by someone who knows far less than he claims to know.
I ignored everything else he wrote after that. I do not deny that a “greenhouse gas effect” exists. Like most global warmist critics, I reject the notion that CO2 at only 0.04% of our atmosphere serves as the sole or even a significant “thermostat” on the Earth’s climate. Water vapor is far more “controlling”, and even that is just one of many factors, not just in the world of astrophysics, but in geology, biology, oceanography, geochemistry, and numerous other fields of expertise.
I absolutely deny that CO2 is the world’s thermostat, and I absolutely condemn all who pretend to know all that is knowable to understand climate changes and who condescendingly refer to everyone else as flat earthers and math deniers.
I think the world is full of math deniers. They are called environmental activists and climate activists. They don’t believe the math regarding what it takes to make their fantasies into reality.
You have to be willfully ignorant to believe it’s possible to remove fossil fuels from our energy sources by 2030, or 2050, for that matter. I suppose it could be done if we substantially lowered our standard of living.
Of course, the activists don’t see themselves lowering the quality of their lives. They believe they are among the elites — and the elites don’t make sacrifices or compromises — only use proles do.
Translation: I know I can’t refute anything the author wrote, so I’ll pretend to be offended by some offhand comment so that I can claim moral authority.
PS: A grand total of nobody here has made the claim that CO2 is the earth’s thermostat. The fact that you have to lie about what the author wrote is further evidence that even you know you can’t refute his actual arguments.
It’s a shame that you got offended and ignored the rest of the post. It seems that had you continued, you would have discovered that you agree with the author.
Do yourself a favour and try to read it all.
“Dr.” Wentworth appears to be one of those who knows a great deal about the least important aspects of the “climate change” controversy and little, if anything, about the important things. Academia is filled with such people. If this could have been solved by a “mathematical proof” of the greenhouse gas conjecture, it would have been solved a century ago by far smarter PhDs than him … and we wouldn’t have squandered trillions of dollars and years of wasted time and effort chasing unicorns.
I like to focus on getting the foundations right.
If people can’t agree about basic physics, their subsequent reasoning is likely to be flawed.
I see little point in talking about complicated issues when people are getting the simple building blocks wrong.
There you go again, assuming you know something not in evidence. You’ve arbitrarily decided that “the GHE” is the foundation. Reading hundreds of opinions offered over the past few days, it seems that what the “foundations” are is very much in doubt. Assuming that “the basic physics” of greenhouse gases in our atmosphere is in some way pivotal to deciding the most important aspects of this debate is so overly simplistic it boggles the mind.
Even if you prove the GHE absolutely, what have you proved when not one model relying on this narrow view has shown any predictive skill? Every scary prediction supported by a myopic over emphasis on the GHE has been wrong. Clearly there’s more complexity here than your hubris seems to recognize. Perhaps the GHE isn’t what we should be looking at … yet it’s the ONLY “science” underpinning the alarmists fatuous “consensus”.
You seem oblivious to the parable of the 6 blind men describing the elephant.
You’re misinterpreting what I’ve said. In no way have I said, nor do I believe, that the GHE is THE foundation.
However, the physics that underlies the GHE is a portion of the physics that is available to determine climate.
It’s very difficult to have a reasoned deliberation about what is or is not important in determining climate when a vocal minority keeps loudly proclaiming that part of the physics is wrong, when it’s not.
What are the basic physical mechanisms affecting heat flow in the climate?
I consider every one of these to be part of the “foundation” of what affects climate.
The ONLY reason I often focus on #2 is because people so routinely say things about it that are not true, and which I have the background to talk about.
If people routinely said false things about another foundational component, and I had the background to talk about it, I would talk about that as well.
If people are believing false things about any of the key ingredients of a puzzle, they are likely to reach incorrect conclusions.
It’s not that I’m inherently focused on one piece of the puzzle.
I’m focused on places where I can see that people are “getting it wrong” with regard to physics, which is an area where I have some formal training.
Beliefs about the GHE are simply an example of a place where some people (not everyone) seem to get aspects of physics wrong in significant ways.
Since you essay was only about the GHE and was in considerable detail, it would seem apparent that you consider it a primary component of the”foundation”, if not fundamental to the AGW conjecture.
Gosh, no kidding. Surely this revelation wasn’t only available to you. Others have been publishing precisely the same discussions for years and still the “consensus” true believers have got it completely wrong … book, chapter and verse. Why would you believe your contribution would be needed?
It may not be wrong, but it very well might be utterly irrelevant. It might also constitute a straw man, like your statement here.
Dear gawd, you can’t really believe all those points constitute the “foundation”. You’ve included virtually everything in your list. There’s nothing left to make the structure. Point #1, insolation would seem to be the best choice as a foundation. You must have read at least a few people saying : “It’s the Sun”.
The problem is; there seem to be a very large number of people with equal if not a superior background who see it differently. Your “proof” is for a hypothetical concept erroneously called the GHE applied hypothetically to a simplistic model of our planet’s inconceivably complex weather systems. That’s called hubris. There are thousands of people at this site with the background to talk about it, and they aren’t all on the same page.
The thing about compelling “scientific” arguments is: if they agree with observations and they don’t result in accurate predictions, they’re wrong h/t Richard Feynman.
Had you ever thought that you might be in the right church but are sitting in the wrong pew? Had you ever considered that people appear to be “getting the physics wrong” because those supporting your view have asked the wrong questions about the wrong things? You’re among, possibly, the most concentrated collection of experts in this field, anywhere on the planet.
Maybe it could turn out to be irrelevant. But, it would be useful to discern if it is right or wrong, irrelevant or relevant. I believe that a lack of understanding about whether it is right or wrong gets in the way of making a correctly reasoned discernment about relevance.
I believe that if you exclude any of those you’ll get the wrong answer, with regard to details of climate.
I believe in applying both reductionism and synthesis, as appropriation.
Reductionism in this sense means that I think it is important to get each building block right.
Synthesis means that I think it’s important to carefully put all the pieces together in a discerning way.
That may not be your approach, but it’s my approach.
So, yes, to me all those pieces are foundational.
Here you are objecting to my wanting a complex, nuanced understanding, and then a few sentences later you’re calling my analysis “simplistic.”
You’re really going to promote the argument that “the majority must be right”—on a climate skeptic website???
My understanding of some issues might be in the minority on this website, but that “large number of people” you are saying “must be right” are a small minority in the global world of science.
You are applying a double-standard if in one case you think the minority must be wrong and in the other case you think the minority must be right.
As far as “equal if not superior background”, I’m curious what evidence you have for this? What fraction of the people involved in the discussions on this website have advanced degrees in physics with a specialty in electromagnetic radiation? Or, if self-taught, have studied physics in a fully integrated way?
I agree that some people on this website know a lot.
But, it’s not clear that they know so much that I should bow down in deference and toss out everything that I learned in graduate school.
This is an instance where the distinction between simple and simplistic is important.
“Simplistic” means one has left out many important details in a way that makes it likely that the results won’t match reality.
“Simple” means it doesn’t take that much to express the argument. It does NOT necessarily mean that there is any doubt about it reflecting an aspect of reality.
There are simple things that one can say which are true about very complex systems, without requiring examining the details of those complex systems:
For example, one can say:
These are things one can conclude independent of the details of the complex system.
I presented a conclusion that applies independent of all the complex details that apply within the weather/climate system.
That’s true. But, not relevant to the current discussion.
You’re arguing that the results of complex climate models have been shown to be observationally wrong. Even if one accepts that conclusion, that is irrelevant to whether or not the particular claims I have made are true.
If you think it’s relevant, then you are lumping dissimilar things together and engaging in black-and-white thinking.
I want to judge each argument on its merits (at the level of both logic and evidence). To me, lumping things together constitutes sloppy logic and is likely to lead to untrustworthy conclusions.
I’m open to learning. But, I’m not going to just role over and accept things that don’t make sense and which contradict the foundations of physics without setting a fairly high bar for evidence.
I’m impressed by the level of knowledge that many people on this website have.
But, I’m concerned that much of that “knowledge” may be filtered through a lens of motivated reasoning.
There are some gems among what is shared.
But, there are also many things said that sound smart and evidence-based and which turn out to be misunderstandings and nonsense when you examine them closely.
My intention is not to prejudge anything. But, neither will I accept surprising claims uncritically.
Why would you want anything different in a community of “skeptics”?
Duane: I suspect Dr Bob Wentworth arrived here with the cliche that the whole place was full of ignorant deniers and wanted to ‘straighten the place out!’. I suspect he will have learnt more from writing here than many of the knowledgeable posters would have gained from his article.
There should be more like him, maybe some would realise that ‘deniers’ are not all ignorant bores.
My post was not motivated by any preconceptions, but by specific experiences I’ve been having with people in the comment threads of this website.
I am making no claims whatsoever about “most” climate skeptics.
My post was in response to a specific vocal minority.
* * *
I do learn from responses. Ideally, it is a mutual learning process.
Duane
“I reject the notion that CO2 at only 0.04% of our atmosphere serves as the sole or even a significant “thermostat” on the Earth’s climate.”
–
“I do not deny that a “greenhouse gas effect” exists”
–
You have to make up your mind.
But.
You have made up your mind.
–
The percentage water vapor in surface air varies from 0.01% at -42 °C (-44 °F)[15] to 4.24% when the dew point is 30 °C (86 °F).
–
In the absence of other greenhouse gases, Earth’s water vapor would condense to the surface.
–
CO2 is the second most prolific GHG.
–
Therefore CO2 is a thermostat of significance
–
Water vapor is also the most important greenhouse gas in the atmosphere. NASA.
– Heat radiated from Earth’s surface is absorbed by water vapor molecules in the lower atmosphere. The water vapor molecules, in turn, radiate heat in all directions. Some of the heat returns to the Earth’s surface. Thus, water vapor is a second source of warmth (in addition to sunlight) at the Earth’s surface.
–
How hot can it get!
–
I know many veteran climate scientists and do not recall any of them denying the existence of the green house effect (GHE) – accordingly this paper is a bit of a “red herring”.
Earth’s temperature is warmed and moderated by the GHE. The primary greenhouse gas (GHG) is water vapour; atmospheric CO2 is a bit player – NOT significant – NOT a primary GHG and NOT a significant driver of global warming.
The following is the cutting edge of the science:
The huge decline in fossil fuel consumption during the Covid-19 lockdown had NO impact on atmospheric CO2 increase – more evidence that Ed Berry’s latest book and paper are correct – see below.
My friend Ed says the increase in atmospheric CO2 is primarily natural, not man-made. The smartest people I know think he is correct.
Atmospheric CO2 changes lag temperature changes at all measured time scales. (MacRae, 2008). Humlum et al (2013) confirmed this conclusion.
Kuo et al (1990) and Keeling (1995) made similar observations in the journal Nature, but have been studiously ignored.
Think about that: Kuo was correct in 1990, and for 31 years climate science has ignored that conclusion and has been going backwards!
Climate Sensitivity to CO2 is a fiction – so small, if it exists at all, it is practically irrelevant.
“The future cannot cause the past.” Here is the proof, from my 2008 paper:
https://www.woodfortrees.org/plot/esrl-co2/from:1979/mean:12/derivative/plot/uah6/from:1979/scale:0.18/offset:0.17
In the modern data record, the lag of atmospheric CO2 changes after atmospheric temperature changes is ~9 months. This is an absolute disproof of the CAGW hypothesis, which states that increasing CO2 drives temperature. “The future cannot cause the past.”
In my 2019 paper below, I explained why the lag is ~9 months – it is basic calculus, the 90 degree (1/4 cycle) lag of the derivative and its integral, which is the ~3 year ENSO period.
My 2008 paper remains very important. My 2008 conclusion was independently duplicated and expanded by Humlum et al in 2013, for which I am grateful.
My 2008 paper has been cited by Ed Berry in his 2020-21 book and related paper, which is at the cutting edge of climate science.
“CLIMATE MIRACLE: THERE IS NO CLIMATE CRISIS – NATURE CONTROLS CLIMATE”
https://amazon.ca/Climate-Miracle-climate-crisis-controls-ebook/dp/B08LCD1YC3/
“CARBON CYCLE MODEL SHOWS NATURE CONTROLS CO2 LEVEL”
https://edberry.com/blog/climate/climate-physics/preprint3/
All warmists and most skeptics argue about the magnitude of climate sensitivity to increasing CO2, and whether the resulting CO2-driven global warming will be hot and dangerous or warm and beneficial. Both groups are probably wrong, because global cooling is happening now, even as CO2 concentration increases.
There is a high probability that the mainstream debate is wrong – a waste of decades of vital time, tens of trillions of dollars of green energy nonsense and millions of lives. Vital energy systems have been compromised, damaged with intermittent, unreliable wind and solar generation – a debacle.
Cheap abundant reliable energy is the lifeblood of humanity – it IS that simple. The green sabotage of our vital energy systems, whether innocent or deliberate, has cost lives and could cost very many more.
Scientific details here:
“CO2, GLOBAL WARMING, CLIMATE AND ENERGY June 15, 2019”
https://wattsupwiththat.com/2019/06/15/co2-global-warming-climate-and-energy-2/
Repeating, “The future cannot cause the past.”
Regards, Allan
I don’t see where the author or I referred only to “scientists”.
rah – I am not disagreeing with you.
I don’t really care about the opinions of non-scientists, most of whom have not spent 10 minutes studying the subject, but still have an “opinion”,
I’ve been reading and posting on this blog for well over a decade. Kiss My ASS!
rah – re-read what I wrote. Repeating, I am NOT disagreeing with you I cannot apologize because I was not referring to you. Your ass remains un-kissed..
My essay was a response to remarks that I have frequently seen in the comment threads on WattsUpWithThat, denying the existence of the GHE.
I get that not all AGW skeptics deny the GHE.
It was simply addressing the subset of commentators who do deny the GHE.
OK – thank you Bob.
You also address any who think mechanisms other than GHE might be important as well.
Well, I address those who think that the GHE is not important to the final 26 degrees of warming in Earth’s temperature.
I do not say, or mean, that other effects aren’t important in affecting Earth’s specific temperature profile.
All my essay establishes is that the GHE is an essential aspect of determining the global average temperature.
Of course other effects also very much matter.
Allan, Dr Berry is simply completely wrong, as I have discussed with him on his blog to no avail…
He made one fundamental error: he used the residence time of CO2 in the atmosphere in reverse direction, which you may do, if and only if, all CO2 fluxes are unidirectional from source to sink. Not if most CO2 fluxes are seasonal and reverse halfway a year and sinks (oceans and vegetation) get sources and reverse…
Which makes the rest of his calculations and reasoning completely worthless…
Hi Ferdinand,
I hope you and yours are well.I am very familiar with your argument, having read it for over a decade. We must agree to respectfully disagree.
I think Ed Berry is essentially correct. So do some of the very best minds on the planet.
To be clear, it is a highly esoteric point, which is not needed to dismiss the fraud of catastrophic human-made global warming.
The simple truth is that increasing atmospheric CO2, whatever the cause, is highly beneficial to humanity and the environment.
Catastrophic human-made global warming (CAGW) is a 50-year-old fraud, a lie from the very start, and the leading proponents knew that from the outset.
Regards, Allan
More here:
https://wattsupwiththat.com/2021/06/03/the-guardian-climate-tipping-points-could-topple-like-dominoes/#comment-3261402
Apart from anything else and regardless of one’s science/math prowess, that is as close to gospel as anything can be. After close to 40 years trying to make sense of this goat rodeo, looking at ALL the arguments and science (especially the geologic record) I have concluded thatno other conclusion is possible. It has been a massive experiment in social engineering and with what they have learned from their apparent success of the AGW fraud, they’re using the Covid “pandemic” as a further link in the chain locking in absolute social control.
Thank you Rory – you are correct.
To your earlier point;
Had this been recognized and acted upon 50 years ago, Marxists like Maurice Strong and all the other loonies who drafted Agenda 21 and set about with their determination to slash population growth, would have had no basis for their “altruism”. The vast sums squandered on global cooling/AGW/climate change could have been used to supply(the above) where it was needed. Affluent, healthy people with light and heat have fewer children.
Just the modest new affluence in China has reduced their population prospects to below replacement. The new policy of three children still won’t stop their shrinking population.
This huge decline in fossil fuel usage was less than 25% and only lasted for about a month. Fossil fuel usage quickly returned to near normal levels.
Mark – no
Allan, man made CO2 emissions are about 4.5 ppmv/year, of which about half is absorbed by vegetation and oceans. Or 2.25 ppmv/year remaining in the atmosphere (as mass, not the original molecules).
That means that the monthly measurements are around the detection limit of the CO2 measurements (0.2 ppmv) and a 25% reduction is simply undetectable in one month.
Only after a full year or even years of a sustained drop in emissions, the difference would be detectable in the huge seasonal and year by year natural variability…
Here is my point:
Over much of the world, the Covid-19 lockdowns are still in effect, now for ~15-16 months or more.
And yet there was no detectible impact on atmospheric CO2 concentrations from the 2020-2021 lockdown of the entire global economy.
Does anyone really believe that we can do substantially more than this full lockdown to cut emissions, to “Save the Planet” from increasing CO2?
Based on this full-scale global test, anyone who still believes we can significantly impact atmospheric CO2 concentrations is utterly delusional.
Look at the big picture – shutting down the entire global economy for more than one year did nothing to reduce atmospheric CO2 concentrations – and yet some say it can be done with little or no pain? Delusional nonsense!
Here:
is someone who thinks the global economy will be ‘shut down’ {and with ‘a lot of pain’}?
‘We’ have ten years?
“ . . . our best estimate is that the net energy
33:33 per barrel available for the global
33:36 economy was about eight percent
33:38 and that in over the next few years it
33:42 will go down to zero percent
33:44 uh best estimate at the moment is that
33:46 actually the
33:47 per average barrel of sweet crude
33:51 uh we had the zero percent around 2022
33:56 but there are ways and means of
33:58 extending that so to be on the safe side
34:00 here on our diagram
34:02 we say that zero percent is definitely
34:05 around 2030 . . .
we
34:43 need net energy from oil and [if] it goes
34:46 down to zero
34:48 uh well we have collapsed not just
34:50 collapse of the oil industry
34:52 we have collapsed globally of the global
34:54 industrial civilization this is what we
34:56 are looking at at the moment . . . “
Thank you Allan for a clear and cogent analysis of everything WRONG about CO2 as anything but a minuscule part of the GHE on Planet Earth. Ninety Nine Percent of the GHG on Earth is WATER VAPOR by Volume or by Percent! Virtually ALL of the atmospheric Energy Reflection is due to WATER VAPOR in all 3 States!
Allan
“The huge decline in fossil fuel consumption during the Covid-19 lockdown had NO impact on atmospheric CO2 increase”
You are looking at the CO2 value only at the bottom of the atmospheric column, most likely Mauna Loa, and it appears that your view of the atmosphere is that it is a closed system. No one has adequately measured the CO2 volume loss at the top of the atmosphere.
The study below indicates that CO2 at the top of the atmosphere is increasing at a faster rate than at surface level. There is only one source of CO2 – the surface. That’s why 2020 values did not reduce at the surface.
Regards
http://www.ace.uwaterloo.ca/publications/10.10022F2016JA023825.pdf
Those that dispute the GHE know incoming energy is greater than outgoing energy.
And how does that counter the possibility of some of that outgoing energy being reflected or absorbed and retained for a time in the atmosphere?
Out of 501 received, 143 is reflected, 98 (pressure) + 260 absorbed. NH 176 is reflected, 98 (pressure) 227 absorbed. SH 111 is reflected, 98 (pressure), 292 is absorbed. Average 240 insulation + 98 (pressure) 338 watts. 20 less than 358 w-m² daytime average.
There is another method of energy transfer in an atmosphere than GHE absorbtion and emission, convection.
Jim, that is true, and it moves heat around within the atmosphere. But it cannot remove heat from the atmosphere. Only IR radiation to ‘cold’ space can do that.
Of course only radiation can remove the heat. I don’t claim otherwise. All I claim is that the surface temperature is NOT dependant only upon radiation loss since the energy at the surface is moved from the surface to the upper atmosphere by conduction and convection, not strictly by radiation.
The radiative heat loss occurs throughout the atmosphere with the “effective” surface some distance above the surface resulting in a warmer surface. I claim this is more due to the convective current transfer than to internal radiative exchanges of greenhouse gases.
There is a window between 8-14 µm where absorption doesn’t occur, transparent to earth’s infrared radiation. Water, land and gases in the stratosphere are heated by the sun. 5.5 x 10^21 insolates 71% of the solar energy where greenhouse gases contribute 2%.Clouds (form of water) absorb the earth infrared radiation at high altitudes.
And that somehow disproves the GHE?
That’s actually concrete evidence that the climate is not in steady-state, but is instead warming.
If “incoming energy is greater than outgoing energy” then if follows, logically, that the “internal energy” of the planet is increasing, and when internal energy increases, temperature increases (though things like ice melting can delay a temperature increase).
Feb-Aug yes, Aug – Feb no. Earth already at 338 watts(98(pressure)+240(Insulation)) and 501 comes in. What’s reflected, what’s recycled. 240(insulation)+98(pressure)+20(days heat),143(reflected). Snow, ice, clouds, ocean changes alters imbalance in a noticeable way.
I monitor the global climate and it is in a steady state, this year was cooler than last year. Sea ice is greater than last year. So you are wrong to say climate is warming. Seasonal change makes this period a warming one. If 667 watts of incoming sunlight strikes the earth, while at the same time surface is emitting 394 watts (394 watts of incoming energy won’t add heat to surface (like a ice cube won’t add heat to water) meaning 273 watts comes in and goes out. Now 10° S latitude sun is more intense and day is longer. At 778 (+111), surface is emitting 443(+49), same thing, first 443 of 778 won’t add heat, so 335 comes in and goes out as the next day surface still emitting 443. or slightly more if day is getting longer and sun is emitting a extra watt to 779 watts. Sorry if this seems condescending but its the way I’m able to explain this.
I don’t have much hope that the sort of analysis you’re doing looking at short periods of time, and particular regions of the globe, apparently without examining the big picture, is likely to lead to anything but confusion.
I didn’t say “climate is warming.” I said that, if the NASA data purporting to show 0.6 W/m² excess of “energy in” over “energy out” over a 10-year period is accurate, then that would be evidence of the planet warming.
I can’t imagine how you quoting figures for a particular year or season or part of the Earth could address that issue.
Physically impossible. If incoming energy was greater than outgoing energy, the earth would be heating up constantly.
NASA data does allege a 0.6 W/m² net imbalance (indicating net heating) over a decade of data. (How much rise in temperature this corresponds to is impossible to determine, without assessing how much ice is melting, and what the overall heat capacity of the system is.)
That amounts to 0.044% of the energy received at the top of the atmosphere, ~0.06% at the planet surface for the disc of the planet facing the sun.
At what level would you accept Total Solar Irradience to change over 100 years? Over timeframes involving RWP, MWP, LIA and other significant climate “dates” until today?
Would you accept an “insignificant” increase of 1% since LIA? 0.1%?
Oddgeir
One thing that’s interesting to me is the total energy involved in the measured imbalance. If my calculations are correct, 0.6 W/m² over 10 years is 1.9e8 Joules/m². If I’m calculating correctly, that’s enough to melt 0.6 m of ice, or to warm the top 45 m of the ocean by 1℃.
I suspect it may be misleading to compare the imbalance of (energy in minus energy out) to changes in the rate of energy in. The rate at which the system comes into equilibrium somehow affects the relationship between the two, so that they are not directly comparable. In general, it’s possible that a large change in total energy input might result in a much smaller energy imbalance observed at TOA.
(Though, I suppose the longer it takes the system to come into equilibrium, the more comparable the two might be?)
I imagine you’re trying to put this energy imbalance into a larger context, comparing it to changes in energy input that have occurred over historical periods?
If so, that’s not an unreasonable thing to think about.
I don’t yet have any particularly useful thoughts on the subject.
Lets go through the math.
Ocean Area -> 3.60 x10^11 sq meters -> Wikipedia
Ocean Volume -> (3.60×10^11 m^2)(1 m) = 3.60×10^11 m^3)
Ocean Density -> 1.024×10^6 g/ cubic meter -> Wikipedia
Ocean Mass
(3.60×10^11m^3))(1.024×10^6g/m^3) -> 9.2×10^16g
Ocean Specific Heat -> 4 J/gK
Q = mcΔT
ΔT = Q/mc
ΔT = (1.9×10^8)/(4)(9.2×10^16) = 1.3×10^-10 K
If you were tracking units, you would see that your result for ΔT doesn’t have units of Kelvins, but of K/m².
I supplied the number of Joules per m², but you applied this to the entire ocean, rather than applying it to a square meter of ocean.
You need to either do everything on a per square meter basis or on a whole ocean basis. Mixing the two leads to nonsense.
Otherwise, my numbers match yours.
Tracking area correctly, one finds that an energy imbalance of 1.9×10^8 J/m² leads to an ocean temperature increase of 45 m⋅K. In other words, it could warm 1 meter of the ocean’s surface by 45 K, or 45 meters of the ocean’s surface by 1 K.
Huh? Try again, in English. Or was it a ‘joke’?
I agree with rah. This site has many excellent scientists discussing relevant details of GHG models. I think we all understand that a planetary body must warm up to re-radiate all the solar energy that it receives. Perhaps, Bob Wentworth, you saw the excellent video, now many years old, in which Anthony Watts debunks a Bill Nye video which claimed to “prove” the Greenhouse Effect? Anthony showed that the video was in fact was mocked-up and thus irreproducible? That sort of GHE tomfoolery from Bill Nye simply degrades the reputation of science. [ Some have pointed out, as well, that greenhouses are not primarily warmed by the “Greenhouse effect” although the GHE is present (glass transmits visible light better than thermal radiation). But this is a red-herring: those making that statement are not denying that the planets (which are immersed in the vacuum of space) are governed by the GHE.
Sites like WUWT are not primarily about the GHE, but rather about compounding effects such as:
Observations also indicate that the Earth’s temperature seems to vary naturally, with Ice Ages and Little Ice Ages occurring in the absence of human industry. This suggests that there may be other forces than CO2 at work ??
So the value of this site is that it challenges the hegemony of the death-by-Carbon narrative, asking difficult questions such as “wouldn’t it be ironic if we undermined civilization with drastic carbon interventions, and it had no impact on the climate?”
“Recalcitrant?” Try mulish, thickheaded, contrary, blind, foolish, vain, etc.
Not a mathemagician myself, I do know GHE is real and works otherwise this would be a barren rock twirling through space. I do not accept that humans are causing the climate to change. Why? Because the climate has always changed and will continue to change, humans are not causing it and can not stop it. Does not take math to see we are all being lied to by a pack of scumbags pushing their leftist political agenda. I will reserve the use of math for useful things, such as construction and ballistics, winning bets about the correct dimensions of the gorgeous female carrying that tray of beer mugs. Ya know? Important, day to day stuff.
The climate has certainly always changed.
so why can it not ALSO change when a new, additional factor arrives? One which involves a proven agent of temperature change and thus climate change?
I laugh every time I see ‘the climate is always changing’ because sure it is and now there’s a new reason why it is changing right now!
What “additional factor” are you referring to?
The climate is changing right now! It must be stopped at any cost.
That’s the delusion, we have a fingerprint control. Only where we put temperature measurements and how we calculate them do we create this illusion.
Is it because the “Ice Age Cometh” prediction that climate scientists predicted in the 1970s didn’t work out?
Does spitting in the ocean make it wetter? Of course, but I don’t think anyone will notice.
Human CO2 contributions to the atmosphere are just spit in the ocean.
What an idiot. You still haven’t shown your evidence after being asked 100-ish times. That’s because you know there isn’t any.
Even people coming to this site for the first time can see what an idiot you are by your no-shows. You are so f-kin useless, I still think you could be a false flag.
Griff doesn’t know exactly because he’s an idiot. He can’t show proof because he’s to ignorant and stupid to be able to put together an argument. But he has faith, he’s a believer
Griff is paid to toss his drive by nonsense
Ban fossil fuel for all but the Faceless Cultural Elite. No wait Griff. Ban the rich and famous as well. If you could but they won’t alter their lifestyle for you. The climate will still change due to natural variability and you need to fear the next cooling event far more than the incremental warming we are enjoying today.
What you wish to believe and fail to sell the rest of us on, because you can’t prove it, is that doubling or even raising CO2 by an order of magnitude will result in a catastrophic event in the next 12 to 100 years (minus the years that have past since the alarmists started the doomsday clock ticking). You are like petulant children demanding that Uncle Sugar remove the monsters in the closet by shutting off the air conditioning in your house in hot and humid Mid-Atlantic/mid July
Bottom line: if you can’t control natural variability, which is just as likely to throw us into a rapid ice age, it is foolish to degrade our quality of life by restricting fossil fuel usage and banning nuclear power generation on the unproven and highly unlikely hypothesis that man can exercise enough power and authority over the planet to control its climate. Which, by the way, has not changed perceptively since the UN chartered the IPCC to find an adverse link between man and the climate. Our CO2 contribution just might have an offsetting affect against the next cooling cycle.
I send this challenge out to you and every person on this board around the world. Explain how the climate, where you live, is appreciably less tolerable, temperature wise, since the IPCC’s inception in 1988. Personally, If I go back to the 1970s with bitter cold and snowy winters and hot and humid summers. I pick 2021s climate without exception. Aside from all this hyperbolic fearmongering from the ruling class and the media handwringers who carry their water.
When the climatistas actually give up all fossil fuel use and stop purchasing anything made with or with the help of fossil fuel- I’ll START to believe they MAY have something relevant to say. If they really think there is a climate disaster about to happen- they would sacrifice all fossil fuels use- do like St. Francis, actually walk the talk.
Somebody in the fossil fuel industry is starting to fight back.
https://www.foxbusiness.com/retail/oil-gas-north-face-billboard-campaign
I laugh every time I see one of your inane posts..
How is the current change in the climate any different than past climate changes?
Again, for the intentionally stupid and obtuse, the climate changes, it always has and it always will, humans are not causing it and can not stop it.
“Again, for the intentionally stupid and obtuse, the climate changes, it always has and it always will, humans are not causing it and can not stop it.”
That argument is so worthless. Like a doctor saying to a patient “people die all the time so don’t worry about cutting back on smoking 60 a day.”
The climate changed before people existed so how do you explain that.
” June 4, 2021 1:45 pm
The climate changed before people existed so how do you explain that.”
Ummm, is that a serious question? OK climate 101. Climate changes when it is forced. Any number of things can cause a change in climate. Sun dimming, volcanoes erupting, the Milankovitch cycle. And…. increasing greenhouse gases.
OMG, that moronic analogy again. Give it up Simon. Show some scientific data, not juvenile crap.
For a start, show us, with the math(s) how humans are going to change the climate. You won’t even start the project because you know what a moron you will look like on here if you even get 1% into it.
Name calling. Hmmm.
Well, it didn’t surprise me that I won that argument in a few sentences.
No, Simple Minded, this is name calling, you juvenile twit.
Retreat! Retreat!
(What kind of being(s) can alter the climate of a planet … Thanos and other Gods. What kind of a person feels that they need to elevate themselves to that level by believing in AGW?)
DonM: “What kind of being(s) can alter the climate of a planet … Thanos and other Gods. What kind of a person feels that they need to elevate themselves to that level by believing in AGW?”
Just spitballing here, but maybe those who got beat up every day and their lunch money stolen?
Simon, how is the climate changing today that has you so concerned?
Not an argument, just the facts. As stated, for the intentionally stupid and dense. Target audience clearly reached! Thanks, buddy.
Simon,
It is not like your make believe doctor statement in any way at all.
Imagine your doctor saying “too much radiation can harm you … don’t ever fly … spending time at altitude increases your exposure and you will die sooner.”
Do you listen, and recommend said doctor to all (three) of your friends and acquaintances.
(What kind of being(s) can alter the climate of a planet … Thanos and other Gods. What kind of a person feels that they need to elevate themselves to that level by believing in AGW?)
“now there’s a new reason why it is changing right now!”
Perhaps a contributing factor- but no proof it’s the magic control knob.
A laugh when I hear “climate change” used in fearful, hushed tones. The climate is always changing, as you acknowledge. So what?
Where is the proof we have a climate crisis? Yes, human civilization contributes to climate change, but that doesn’t mean it’s driving climate change to a significant degree.
People who make extraordinary claims need to offer proof. “Could” and “may” are neither proof nor evidence. The null hypothesis has not be disproven.
Griff, most people here acknowledge some human effect on CO2 levels, not necessarily temperature though (maybe UHI). The question is: is our affect all bad. NO!
Let’s say all humans except 100k disappeared from the earth today. Those remaining 100k would STILL have to deal with changing temps, rising/lowering ocean levels, droughts, etc. You have implicitly acknowledged this.
Except they would NOT have cheap energy to help them adapt.
I have seen this message consistently on this site for years: whatever affect humans have on the climate is negligible at best and also with positive effects (e.g. greening of the planet). And the best way for humans to deal with future problems is with cheap energy. i.e. get people OUT of poverty not deeper into poverty to better be able to adapt to a change in climate.
What we are doing now will solve NOTHING, and yet destroy our ability to adapt in the future if we need to.
There’s probably many reasons why the climate is said to change. A degree or so of warming over decades, even if it were true and all attributed to co2, is not proven to change the current or future climate in any appreciable way. And “climate” is a loaded term, begging to beg the question. Ex: the world is much cooler today than it has for the vast majority of the last fifty million years. It doesn’t come close to anywhere near an average, and it isn’t proven that temp changes are “faster” than other times in the past, or that recent temp changes have made any appreciable difference in the world.
I can’t tell the difference in a degree, nor can my dog. There are no mass extinctions because of such a small change, unlikely to increase in the future, nor are there more severe weather in general, or hurricanes, or anything. If there are at all it is drowned in all the hype and alarmism.
If CO2 were the powerful molecule that you are paid to believe it is, then without CO2 changing, the climate wouldn’t change.
The fact that the climate has changed by greater amounts at times when CO2 wasn’t changing, is sufficient to disprove your belief that current changes must be caused by CO2 changes.
That is completely fallacious reasoning.
It’s like saying, “if being shot by a bullet is so effective at killing someone, then without people being shot nobody would die.”
Greenhouse effect means more energy is emitted than it actually receives and is greater than emitted to space. Receives 501 watts, reflects < 143 watts. Insulation 358 (depended on time of year and snow/ice extent), 143 + (240(outgoing IR) + 118) = 501 total out. Received and total out to space equal.
That is definitely not what the GHE means. Where did you get that idea?
That’s not the case as I have shown. 501 w-m² (45°) > 358 is it not. 1000 w-m² (0°) > 460 is it not. Only if you dilute solar energy and inflate what the surface emits then you have a artificial greenhouse effect. This is what models have done. Flattened the earth (no seasons, nights) no internal flow of insolated energy that can be doubled (480 (insulated, 240 (incoming, outgoing)) at the equator (only rise and fall by 20-40 watts). Polar regions when long periods of zero sunlight gets lower than 240 by 50-60. Models manufacture the climate with 240 watts insulation and anything above that caused by greenhouse gases. It’s not reality at all.
So, are you telling me greenhouses don’t work? Not really seeing the relevance of this to leftist scumbags lying about humans destroying the climate. Walk us through it.
“I do know GHE is real and works otherwise this would be a barren rock twirling through space” You ignore the possibilities that mechanisms other than GHE might be in play?
Just one in the myriad of beautifully intertwined players in the vast cosimic dance we call existence. 😉
So I am not a scientist, but could someone who is tell me if this is about the most useless article ever written. It appears to have the single goal of shutting down a debate that doesn’t exist. Does anyone really doubt that a GHE could exist in a closed system. I have never met this person, but maybe that’s the authors mysterious “math skeptic” to which I have also not met. I only doubt anyone’s ability to measure the GHE of carbon dioxide on earth. I’m not a mathematician, but even I can see that this simple proof is missing about 10,000 variables before it can cross that chasm. Please repost this article when you can prove that.
So you don’t believe 1+1 =2? </sarcasm>
1+1=1 Boolean logic
‘1’+’1′ = “11” for concatenating characters to form a string.
Actually 1+1=0, with a carry of 1 Boolean logic
Or you could say 1+1=10
There are 10 types if people in the the world, those that understand binary, and those that don’t.
1+1 actually can equal 3.
1.4 + 1.4 = 2.8.
Now round to the nearest integer:
1 + 1 = 3
Disagree. People who deny the GHE regularly post here.
…. not to mention the climate liars, crackpots and parasites who regularly and fraudulently deliberately try to conflate its (proposed) non-existence with its effect in the real world at levels above 280ppm, a bogus conflation that you yourself (Mark S, that is) appear to have fallen for. and you can easily read about above.
Apologies for sounding rude Mark S, but just trying to tap you on the shoulder, real hard.
Show me Mark S. I’ve been reading this blog and entertained by the comments for a long time. I’ve never noticed much denial of facts, math, evidence, proof, etc. The skepticism here is focused on assertions, claims, beliefs, dogma, and everything Michael Mann has ever said. The reason I like this site and read the comments is because they are mostly made by informed people using reason and logic.
Then there is the Griff. He is almost too perfectly illogical and seems driven by some weird faith system. The skeptic in me wonders if he is not in reality a figment of a WUWT site owner meant to generate controversy and interest.
names?
So, you can’t remember the names of the “People who deny the GHE (that) regularly post here?
I often read posts claiming the GHE is not real. I like to think that’s because the “green house effect is a misnomer” — Green houses don’t work that way.
Not so long ago, it was commonly believed the glass in green houses allowed light to enter but trapped the IR and other parts of the spectrum. It’s been shown this is not correct.
I routinely see people in these comment sections denying that the GHE exists, and ridiculing anyone who claims otherwise.
The analysis in the essay specifically shows the the GHE is active on Earth, and is needed to explain 26℃ of Earth’s temperature.
This essay is not about the particular influence of carbon dioxide.
It’s about the the GHE in general, and the portion of the community that denies the existence of the GHE.
Large problems can be sorted out by taking things one piece at a time. My essay attempts to tackle one small piece of the larger puzzle.
I doubt GHE exists. A closed system doesn’t allow the transfer of matter, energy is allowed. Matter I’m referring to 78% nitrogen, 21% that is in motion at 340 meters per second providing earth with 340 watts of insulated energy. Both in the ocean and in the air. An example is a e-bike 500 watt ebike can get to speeds of 20mph. Power (sun powered pressure) keeps air particles in motion at 340 watts per meter per second, refreshing that energy every day.
“If the average surface temperature of the planet (or object) is higher than this limit, then that can only happen because of the presence of LW-absorbing (or reflecting) materials between the planetary surface (or object surface) and space.”
Or that the oceans absorb SW energy to be moved polewards
No, that sort of process can only move the average temperature from below the effective radiative temperature towards the effective radiative temperature. The math specifically says any processes not involving LW absorption/scattering can’t raise the temperature beyond that level.
Bob, you are talking about an average of the entire atmosphere while Pablo is explicitly talking about the average at the surface. the average surface temperature can clearly be higher than the blackbody temperature and that can happen (due to convective upwelling) without requiring the LW absorption.
No, my essay is about “the average at the surface.”
No, that is specifically what my essay proves cannot happen.
“No, that is specifically what my essay proves cannot happen” I see no such proof in your essay. Instead I see only assumptions that it doesn’t occur.
To “prove” something doesn’t exist I think you should at least address it. Maybe I missed where you did that.
If someone offered a proof that “Adding any two odd numbers produces an even number”, there is no need to address the special case of “But what about 79 + 23?” The fact that the proof does not explicitly address the case of “79 +23” does not make the proof inapplicable to that case.
I offered a logically correct line of reasoning that established, provided you accept the Stefan-Botzmann Law, that the average surface temperature cannot be greater than the effective radiative temperature Tₑ if there are no LW-absorbing/scattering materials in the atmosphere.
This was a result that is conditioned only on the stated assumptions. It is always true, if the S-B law is true.
So, in particular, it is true if there is no convection. And, it is true if there is convection. It is true if the Earth is heated geothermally. It is true if the Earth is not heated geothermally. It is true if polar bears live in the Arctic. It is true if polar bears do not live in the Arctic. It is always true.
Examine the logic of the argument. Everything in the argument is true if there is convective upwelling, and is also true it there is not convective upwelling.
There is not a single line of the derivation which depends on whether convective upwelling is present or not.
Jim, thanks for your comment.
I think that we have to clarify that actual surface temperatures on land are much higher during the sun-lit day than the height at which temperature readings are taken, i.e. the height of a Stevenson screen.
It is interesting that the theoretical temperature of the near surface air of our atmosphere should be plus 60ºC with a skin temperature at 10km altitude of minus 60ºC. according radiative transfer theory.
Convective upwelling actually moves energy away from the surface faster than radiation can.
The oceans are a different story.
A highly convoluted way of saying that a grey body which absorbs some of the energy received can achieve a higher temperature than predicted by the black body S-B equation.
The real issue is whether the absorption is via back radiation or by conduction and convection.
Currently, the climate establishment ignores the latter.
Once a grey body arrives at internal thermal equilibrium it will mimic a black body when viewed from outside.
Stephen, actually the article proves that atmospheric absorption of IR radiation is necessary for the observed temperature to be achieved.
It says nothing about conduction and convection which are capable of producing the observed outcome.
It mathematically proves that atmospheric absorption of IR radiation is necessary to produce the observed outcome. No other mechanism (conduction, convection, anything) is capable if there is no absorption of radiation. That is the outcome of the proof.
Not true. The proof says nothing about the other effects and explicitly ignores them. The fact is that convection demonstrably moves significant amounts of energy from the surface to the upper atmospher and MUST be considered as one of the components that keeps the surface warm!
The proof ignores those other effects in the same sense that a proof that 1 + 1 = 2 “ignores” whether it is also true that “3 × 4 = 12.” The existence of those other effects does not affect the proof.
The proof is valid regardless of those other effects.
Nothing about those other effects can possibly affect the truth of what has been concluded.
Certainly true. And utterly irrelevant.
You’re saying that a process which removes enormous amounts of heat from the surface (i.e., it cools the surface) must be considered as one of the components that keeps the surface warm?????
I’m afraid I’m not following your logic.
I am saying that anything that removes enormous amounts of heat must be considered as part of any calculation of surface tremperature and igoring it results in likely in correct conclusions.
In another post you point out that it is steady state which is important. Once that steady state is reached somethign MUST move heat from the surface to space. A transfer of ALL the solar energy MUST be present. To put it simply something has to “cool the surface” to prevent it from heating without bound.
I simply claim that convection is probably the major medium of such transfer, just as you claim radiation is the only medium.
Please point me to any place where I have ever claimed that “radiation is the only medium” for transporting heat from the surface. I never have, and never will.
What I have done is to make a more subtle argument: that certain limits can be established by considering only the radiative component of what is happening in the system.
That’s not at all the same thing as ignoring other effects, or claiming radiation is the only energy transfer mechanism.
It depends on how you define “the major medium.”
Ultimately, 100% of the energy that reaches space reaches it radiatively.
If you look at how energy leaves the surface, NASA data indicates that 65% leaves via convection and 35% leaves radiatively. So, I agree that convection is the major medium of energy transfer away from the surface.
However, if there were no GHGs, then convection would not be able to cool the surface at all, since there would be no place for convected heat to go. For convection to cool the surface, it relies on the ability of GHGs in the upper atmosphere to radiate heat to space.
Thus, convection is a very important heat transfer mechanism—but it could not cool the Earth’s surface in the absence of GHG.
And, all this talk about “cooling” doesn’t directly tell us much about the mechanisms that produce warming.
I’m not going to restate things I’ve already said but regarding “all this talk about “cooling” doesn’t directly tell us much about the mechanisms that produce warming.” I use “the term “cooling” since anything that removes heat energy from the surface is “cooling” the surface. Maybe not precise terminology but a kind of shorthand for the energy transfer.
Given that the surface is a manifold and a thermal continuum, yes it certainly does keep the coldest parts warmer! 😉
No, the proof clearly establishes that no effect not involving the absorption/scattering of IR radiation is “capable of producing the observed outcome.”
I say again that your “proof” does no such thing. It simply ignores and dismisses the possibility.
Would you be willing to actually read the proof?
Please look for any step that would be false if convection is important. If you understand what I’m saying, you will not find any such step.
It doesn’t ignore convection, it offers a conclusion that is true independent of convection.
But not independent of conduction, simply because conduction removes the possibility of negative thermal gradients that are inherent to radiative flows in isolation.
Nowhere does the proof mention a “black body.” It explicitly assumes a grey body, with an emissivity 𝜀. You have clearly not understood the argument.
No. The argument only cares about absorption of radiation, not absorption of “energy.” Conduction and convection can transport thermal energy, but they do NOT absorb radiation.
Therefore, the proof establishes conduction and convection are incapable of explaining the observed warming.
I can’t think of any way of interpreting this statement that would make it true.
Do you know what the terms “black body” and “grey body” mean?
“The argument only cares about absorption of radiation, not absorption of ‘energy’.” Conduction and convection can transport thermal energy, but they do NOT absorb radiation.”
Radiation also only transports the energy. Conduction can cause an “absorption of energy” because it is the molecular transmission of thermal energy from one material to another.
Convection is in play because it is an effective method of energy transfer which is what the entire discussion is about: how energy moves from the surface to space in a way that allows the surface to be warmer than is explainable through direct transfer of energy through radiation to space.
I don’t agree with your summary of what the entire discussion is about.
The essay shows that, without needing to look at any of the details of “how energy moves from the surface to space,” one can still draw certain rigorous conclusions that must be true, regardless of those details.
You seem to be assuming the argument presented is something different than it is.
* * *
The argument depends only on these two assertions:
Do you disagree with either of these assertions?
Do you think that either of these assertions is false because convection exists?
Strictly speaking, conduction is radiation absorption at the boundary layer.
Hmm. I think that, to the extent that a gas participates in radiative heat transfer, this would be true.
But, conduction can, and does, also reflect heat transfer through gas molecules colliding with the solid or liquid surface, and exchanging energy with the vibrations in that solid or liquid.
That would seem to be a superficially non-radiative process. Though, the collisions are, of course, ultimately electromagnetically mediated.
I don’t want to go off topic, but why is the surface temperature of the asteroid (dwarf planet) Ceres measured at about -40 F degrees? It has a radius of 180 miles. No atmosphere (obviously) Lots and lots of water-ice.
Ceres’ daytime temperature is about -100 F and nighttime -225 F.
The surface is relatively warm for an asteroid, the average surface temperature is about 235 degrees Kelvin or minus 36 degrees Fahrenheit or minus 38 degrees Celsius.Sep 25, 2019
https://nineplanets.org › ceres
Ceres Facts | Orbit, Composition, Size, Gravity & Definition – The Nine Planets
It has a transitory atmosphere also
This is not a mathematical,proof. It is a mathematical derivation based on a large number of physical assumptions and claims. In logic this is called an argument. Pure math has proofs, but physics does not, and that is far too strong a term to use. (The insults in your intro do not help.)
While I accept GH theory, it is complex and by no means settled. I know of several competing versions. Your argument does not reflect this fact. So you are overstating.
“This result can be proven if one accepts a single principle of physics:”
Conditional proof is not proof.
All mathematical proofs rely on one first accepting certain premises. (In mathematics, those premises are called axioms.)
No, in math the premises are normally true by definition. (Euclidean geometry is an exception.) In science the premises are never certain. That is the difference between math and science. 1 + 1 = 2 is not an empirical claim. The SB equation is.
Also science demands that the appropriate math be used. You can’t “prove” that the area of a 3×3 foot carpet is 6 by adding 3 and 3.
No, in math the premises are always assumptions. An axiom is something you assume to be true because you can’t show it otherwise.
I addressed the issue of “proof” in Appendix 1. What I actually proved is that the GHE is an inherent consequence of the S-B law.
Not all assumptions are axioms
David, physics does have proofs, so long as you accept that physics can be described by mathematical laws. The proof in this article has only three assumptions which are clearly spelled out. These are 1) the Stefan-Boltzmann law, a well established law of physics, is true, 2) conservation of energy is true, and 3) reasonable numbers for the emissivity of the surface
Don’t forget the partially hidden one:
4 – ONLY radiative transfer can remove heat from the surface. A clearly false assumption.
It is true that only radiation can remove heat to space. The proof still holds if other mechanisms transfer heat from the surface to the atmosphere. The outgoing energy from the planet is determined solely by radiation.
True but the argument is about surface temperature and a large portion of the surface thermal energy is moved to the upper atmosphere through convection where it is radiated into space. That can account for the surface being warmer than the blackbody temperature. The article ignores this.
Jim, this is all correct, but I think it illustrates the key point you’re missing. Greenhouse gases are the gases in the atmosphere which absorb radiation. They are also the only gases which emit radiation.
So without greenhouse gases, all outgoing radiation would come from the surface. And therefore the outgoing radiation would be determined entirely by the surface temperature, regardless of what the atmosphere was doing.
“They are also the only gases which emit radiation” Not true. All heated substances (including gases) release radiation. If only greenhose gases emit radiation then a planet without them would become extremely hot since it wouldn’t be able to radiate any energy and would trap it all.
Even if it is true that it is only the “greenhouse” gases that emit radiation, the convection moves them to the upper atmosphere and away from the surface so that the surface is warmer due to the convection rather than to the percentage of greenhouse gases.
Perhaps it isn’t quite correct to say “outgoing energy from the planet is determined solely by radiation”: It may be a relatively small amount, but isn’t atmospheric mass constantly lost to space? Since it wouldn’t be at absolute zero, it would take energy with it, right?
Of course, there is a constant addition of mass, too. Over time, is there a net gain of mass to our planet, or loss? I really don’t know.
Further complicating things, incoming mass may be incredibly cold when it arrives TOA, so it acts as a heat sink, yet it probably arrives at velocities that represent lots of incoming kinetic energy – more than enough to make up for it’s frigid temp? And, even if it lazily settled into our atmosphere, extremely cold with little to no motive energy, it still ought to provide a one-time jolt of kinetic energy to our planetary system as gravity accelerates it toward the surface.
(I admit, the net effect of mass entering and exiting Earth could be like CO2’s effect: real, yet really small)
Minute amount of internal heating too.
That would be a false assumption, but it’s not an assumption that I made.
Of course other processes remove heat from the surface.
Yet, none of those other processes can change the fact that the amount of radiation produced by a surface obeys the Stefan-Boltzmann Law.
Of course you made that assumption. I quote: “If the average surface temperature of the planet (or object) is higher than this limit, then that can only happen because of the presence of LW-absorbing (or reflecting) materials between the planetary surface (or object surface) and space.” My emphasis.
You completely ignore all other possibilities like atmospheric convection moving the effective emitive surface higher into the atmosphere.
It sounds like you don’t like the conclusion, and so you are falsely inferring that some assumption must have been made.
My conclusion was based on a series of steps. Please point to any step along the way where something would be false as a result of atmospheric convection being present.
Yes, there is atmospheric convection. And, one could think in terms of there being an “effective emission surface” at some altitude.
None of that changes the fact that there is an actual planetary surface, with actual emission characteristics, and that one can reason (as I have) about those emissions.
If you think there is something wrong with the conclusion, what steps along the way do you think are invalid?
I don’t think anything is invalid. I just think something is missing.
If you can point to “something missing” that would change anything in the argument, I’d be interested to consider it.
Jim clearly stated that your definition of a surface is probably wrong. Where is this surface? At sea level? At the edge of the atmosphere? Define edge, etc.
By “surface”, I literally mean the surface — the interface between the solids on the land or the surface of the oceans, rivers, or lakes.
I must mean this because this is the only place where the Stefan-Boltzmann Law is rigorously valid, and my argument is about a place where the S-B Law is valid.
Surely there are also several assumptions about radiation physics and GHG molecules. If you can derive the GHE without GHGs I wouod love to see it.
Plus a bunch more if I looked, especially if we get into the magnitude of the GHE. There is a paper around that argues that much of the 33 degrees or so of warming attributed to the GHE is actually a positive feedback from increased evaporation on this watery planet.
And as I mentioned, there are two very different versions of the GH physics. One says the energy of absorption is lost kinetically and this creates the effect. The other says the atmosphere is in “local thermal equillibrium” so the atmospheric warming comes from surface warming plus convection. I find the latter incoherent but am told that is the model now taught in American universities.
It would be funny if this so-called “mathematical proof” were merely qualitative!
Then too SB is a law of black bodies, which the Earth is not, so this assumption is false going in.
When one includes an emissivity factor, 𝜀, as I have done, the SB law applies to “grey bodies” as well, and Earth is certainly a grey body. So I dispute the idea that any false assumption has been made.
So, you’re assuming, without evidence, that there are assumptions?
My derivation assumes nothing about radiation physics beyond the S-B Law, and requires no assumptions about GHG molecules.
I did. Read the essay if you’d like to see it.
(Admittedly, it depends on what formulation the the GHE one is talking about.)
Unfortunately, not everything that’s been written is correct.
The argument I’ve offered says that the argument in that paper can’t be correct.
Neither of those “versions of the GH physics” seems coherent. I think you’ve misunderstood what you’ve read and heard.
There is still some debate thet the S-B law does not apply to gases.
Also true. And applied to the Earth it is merely an approximation.
The relevance to gases is well-understood by scientists, even if internet commentators often get the issue wrong.
This particular essay, however, applies the S-B law only to the planetary surface. So, there shouldn’t be any question about its applicability.
So, you have a PhD. That’s no guarantee you can’t be wrong, mistaken, or full of baloney.
To move fluid through a hydraulic resistance requires a pressure difference.
To move current through an electrical resistance requires a voltage difference.
To move energy through a thermal resistance (atmosphere) requires a temperature difference.
Q = U A (Tsurf – Ttoa)
That explains why the surface is warmer than ToA. No different from the insulated walls of a house. No esoteric jargon, nomenclature and handwavium, just every day engineering.
Even if GHGs could do your hocus-pocus at 0.04% they still would accomplish nothing significant.
The effective emissivity of the SURFACE is NOT 0.95. More like 0.16. 63/396 or 0.39 63/160
1) By reflecting away 30% of ISR the albedo, which would not exist w/o the atmosphere/GHGs, makes the earth cooler than it would be without that atmosphere like that reflective panel set behind the windshield. Remove the atmosphere/GHGs and the earth would become much like the Moon and Mercury, a barren rock with a 0.1 albedo, 20% more kJ/h, hot^3 on the lit side, cold^3 on the dark. Nikolov, Kramm (U of AK) and UCLA Diviner mission all tacitly agree.
2) the GHG up/down welling, “trapping”/”back” radiating/delaying/intercepting, 100 % efficient, perpetual warming loop requires “extra” energy (violates LoT 1 & 2) which according to RGHE theory comes from
3) the terrestrial surface radiating that “extra” energy as a LWIR ideal black body which
4) cannot happen because of the non-radiative heat transfer processes of the contiguous atmospheric molecules and as demonstrated by experiment, the gold standard of classical science:
https://principia-scientific.org/debunking-the-greenhouse-gas-theory-with-a-boiling-water-pot/
1+2+3+4 = 0 Greenhouse Effect + 0 Greenhouse gas warming + 0 man caused climate change.
How the Earth actually heats and cools with Mr. 3 Legged Stool – Trailer – YouTube
Version 1.0 060421
The underlying idea of this post is an extreme simplification of the Planet Earth. A reduction to a uniform temperature. The temperature difference between polar regions and tropical regions is 139 F (South Pole minus 56 F, Singapore 84F) – can you really neglect it?
“extreme simplification”
Kind of an understatement.
Simplified to absurdity.
A 1.5 C rise in the GMST anomaly over 140 years out of a min/max range of 150 C is a statistical aberration and not a meaningful number let alone a trend.
Here’s simple.
Pull the draperies across a large south facing window at noon mid-August. Is the room cooler now or warmer?
Pull the draperies across a large north facing window at 10 pm mid-January. Is the room cooler now or warmer?
The albedo cools the lit side while the thermal resistance (aka blanket) warms the dark.
The surface gets warmer as the albedo decreases.
No albedo and the earth gets the full 394 K, 250 F.
I agree with that.
It’s actually one of the simplest ways of explaining the GHE: introducing LW-absorbing/scattering materials introduces “thermal resistance” to radiative heat transfer, thereby yielding an increase in surface temperature.
If you include the effects of water in the GHE, LW-absorbing/scattering materials in the atmosphere apparently intercept around 90 percent of radiation emitted by the surface. Carbon dioxide (at 0.04%) may intercept up to 8 percent.
There are many kilometers of atmosphere, and small effects can add up over distance.
This is something that people can and do measure. Your claim isn’t remotely plausible.
It’s a silly enough claim that I don’t have much hope for engaging the rest of what you’re saying.
Q = U A dT is not specific to the GHGs nor LWIR.
I demonstrated why 0.95 is not possible by experiment.
Just the arithmetic bookkeeping of the balance diagrams show how it is not possible.
The IR instrument readings are not applied or corrected properly.
And I demonstrated by experiment why that is.
I don’t think most folks here deny that the GHE is real. What they don’t agree with is the idea CO2 is a control knob for climate. It isn’t. One can believe that the GHE is real and still be a skeptic.
Agreed. The tough part seems to be finding any agreement on exactly what portion of the GHE can be attributed to Carbon Dioxide in the atmosphere.
pretty much Zero is the impact. the mathematical gymnastics and many variable that overwhelm the claimed impact demonstrate the entire absurdity of CO2 as a dangerous GHG.
I don’t think there is agreement on how much of the warming (basically method of transfer of energy from the surface to space) is due to GHE either. I, for one, believe it is overrated, convective currents being the main contributor.
If you have been following WE’s emergent phenomena series you will know that the greatest GHG which is water in it’s 3 states is also the greatest coolant at the same time.
The ceres data that he analysed seemed to show a slight negative impact overall.
“One can believe that the GHE is real and still be a skeptic.”
And still be wrong. Lukewarmers fit your observation perfectly.
If you accept the Greenhouse effect, then how can you not accept that putting more CO2 in the atmosphere produces warming?
There is no doubt about the Greenhouse Effect and no doubt either there is more CO2 in the atmosphere and that it is human produced CO2.
Seriously are you that ignorant of what climate realists think on the CO2 warm forcing effect?
From what I’ve seen here, climate “realists” are all over the map wrt that and other effects.
Most climate realists accept CO2 have a warm forcing effect, that most agree it is a diminishing effect with additional CO2 added into the air.
CO2 has NEVER been shown to drive the climate, that only rational people understands.
I can agree with a lot of that because for some reason, some good scientists on here, who should know better, seem to want to write long essays about the greenhouse effect and CO2, but yet fail to mention that it’s what happens above 280ppm that is (purportedly) the anthropogenic component of any effects on global climate. I continue to lose that battle, but the game’s not over yet.
Let’s ban water.
But, Griff, there is plenty of doubt as to exactly how much atmospheric warming can be directly attributed to recent human Carbon Dioxide emissions. The doubt ranges from the extreme “all of it” to the more reasoned observational “barely measurable”.
I feel certain you’ll not accept this inconvenient doubt.
Griff, it’s that “logarithmic effect” thingy that puts the brakes on CO2’s magical atmospheric warming powers.
What that means is that the usual “more is better” logic does not apply to CO2 warming the atmosphere.
More CO2 as fertilizer though, is a different story. Plants can’t get enough of it.
Ha ha yes, griff and loydo more prominently, make posts saying that they get the logarithmic effect and then follow up with posts that clearly show that they don’t.
If I thought that they could work a calculator, I’d have them do the linear calculation – 420 over 280 times 288K. Whoaaah, I need to go get my shorts on and a long gin and tonic just thinking about that.
I’ll take the question seriously and reply to it.
That there is a GE is not in dispute. Nor is there any dispute that due to human emissions there is now more CO2 in the atmosphere than there was 200 years ago. It does not however follow from this that raising CO2 ppm will raise temperatures.
This is a question about how the climate and global temperatures respond to forcings.
There can be no doubt that increasing CO2 will produce a warming effect. But the question is, what is the response of the climate and global temps to that warming.
There are a number of possibilities. One is that the result is to raise the global temps by the amount of forcing that warming impulse gives. That seems to be roughly 1C. A second is that this rise of 1C prompts further warmings due to increasing water vapour, and so the final destination of a doubling of CO2 ppm is about 4C. A third is that the rise leads to countervailing cooling mechanisms which result in no warming at all over a longer period. Or, it could lead to oscillations in a warming/cooling cycle.
They are all perfectly possible. To find out which if any happens you have to do observation. The question is not whether heat is being applied. The question is what effect it will have on the climate machine. And you cannot know the answer to this from the size of the heating effect.
As an example, suppose I wrap myself in an insulating quilt. Does that raise my temperature? No, because I start sweating and respond to the increased insulation by a cooling reaction. Similarly if I am outside on a hot day.
The debate and uncertainty is not about whether an increase in CO2 ppm will deliver a warming force. It will. Its about whether the climate of the earth is so constituted that this warming effect will result in a global rise in temperature, and if so how much.
This is not at all obvious, and you cannot make any prediction from just knowing the parameters of the warming effect. Just as you cannot predict my temperature by knowing how thick the quilt is in which I have wrapped myself.
Sometimes people who should know better argue that AGW is ‘just physics’. Its not, and its not about the properties of CO2. Its about something different and much more complicated, its about the functioning of the climate. Its about engineering.
The argument from CO2 is, to take another example, a bit like hoping to predict how far a car will travel on a gallon of gas based on the properties of the gas. No, you cannot do that either. You have to look at the machine itself, how much wind resistance, how much wastage in heat, how complete the combustion, how much it weighs….
The Climate Scammers depend on water vapor amplification to push ECS above 1.8 K/2xCO2 it is with GHG theory. The IPCC CMIP 3/5/6 push their ECS to above 3.0 K now with fake wv amplification. It is the WV amplification where the climate fraud lies in the atmopheric to human increases in CO2 response claimed by the scammers.
do all the mathematic gymnastics you want. the impact of CO2 in any equation to support that Hypothesis is already past its saturation point. The other variables are so large vs. any CO2 impact as to make it completely irrelevant. CO2 is Life, along with H2O and are the things that keep all us Carbon Life forms sustainable.
Well said. Leftism/Globalism/Statism are ultimately anti-human and anti-life.
You are totally right with the first sentence, and I find it funny how many down votes there are. Essentially global warming is nothing but an increase of the GHE. So if GHGs cause a 33K GHE and you increase GHGs (directly with CO2 or indirectly with vapor), that 33K figure will grow. There is really no point in doubting global warming, if you endorse the (GHG induced) GHE. And I thank you for rightfully pointing that out.
However reality is a bit more complicated. GHGs do not really cause any GHE, but that is something we are yet to learn. I mean have not posted the whole story yet. 😉
Well.. I can give you this little preview on preliminary results (it is far worse in the end..)
You see it but you deny it. CO2 has increased thanks to a warming climate. CO2 isn’t the control knob
99.9% of sceptics agree that humans are having an effect on warming, griff. That isn’t the issue. The problem is the magnitude of the effect.
The plain truth is that every single piece of “evidence” of the MAGNITUDE of man-made warming is based on statistical analyses and computer models. It has to be this way because no thermometer has ever been invented that is capable of measuring temperature “caused by man” vs temperature “caused by nature”. For pretty obvious reasons this will always be the case.
The problem is that climate is unbelievably complex while weather is chaotic, which means your statistical analyses and computer models are wide open to huge errors — and there is nothing you can ever do to change this fundamental fact regardless of how powerful your computer or statistical analyses might be.
If you don’t believe me, here’s a simple question that should be very easy to answer. Tell me the confidence level of the predictions being made about global warming and climate change. You will NEVER see these for the simple reason they’ll be pretty much zero. Climate ‘scientists’ get around this problem by just ignoring it and it’s unbelievable they’re allowed to get away with it. ANY proper scientist will tell you that a statistical analysis or computer model that doesn’t show confidence levels isn’t worth the paper it’s written on.
Put very simply, climate ‘scientists’ are making predictions to levels of accuracy that themselves are lower than the margins of error to which they can be predicted. It’s like saying “temperatures will increase by 2.3 degrees C, plus or minus 20 degrees C”. Absolutely nonsensical.
It still amazes me why statisticians don’t just call this stuff out for what it is, which is witchcraft. Maybe they’re just frightened of losing their jobs if they do so.
This. To prove that climate models can predict future temperature response to increased CO2 would require comparing climate model forecasts to prospective out of sample temperature data. But climate scientists have allowed themselves to reverse the null hypothesis so that the models don’t have to have proven statistical accuracy and precision. Because climate change. So now we have repeated climate model generations with advancing hindcast/forecast lines, that can never be proven wrong, just improved.
Interestingly, AR5 Figure SPM6 shows graphs of temperature anomaly vs models with the explanation: “Model results shown are Coupled Model Intercomparison Project Phase 5 (CMIP5) multi-model ensemble ranges, with shaded bands indicating the 5 to 95% confidence intervals.” This shows either ignorance or willful misrepresentation.
“If you accept the Greenhouse effect, then how can you not accept that putting more CO2 in the atmosphere produces warming?”
The situation is more complex than you appear to appreciate, Griff. Greenhouse gases are not only better absorbers of longwave radiation than the nitrogen and oxygen that make up most of the atmosphere, but they are also better emitters of it too. This means that where GHG-molecules typically are able to absorb energy from collisions with other atmospheric molecules faster than they can receive it from surface emissions (as they may do where the surface radiance is relatively slight, such as in polar regions and in the upper atmosphere for examples), their greenhouse properties flip over into ani-greenhouse properties and they act to cool the planet by providing a conduit for the faster emission of atmospheric energy to space than would be possible without them.
In short, if one accepts the greenhouse effect, one must also accept the anti-greenhouse effect that automatically comes with it in the colder regions of the atmosphere. This potentially dual nature of GHGs makes for some impossible mathematics that are currently far beyond the power of any existing computer models to embody and resolve.
Under some circumstances, then, adding more CO2 will not cause warming, but quite the opposite, in fact.
It’s true that GHG produces cooling in the upper part of the atmosphere.
Though, I wouldn’t personally call this an “anti-greenhouse effect” because it doesn’t in any way contradict the principle that the planetary surface is warmed by GHGs.
I don’t know where you’re getting this idea from.
To the contrary, these mathematics are easily dealt with, and are dealt with by every serious climate model. Even I could easily write a climate model to address this issue (though I’m not sure there would be a point to it).
There are tricky aspects to climate modeling, but, to my knowledge, this isn’t one of them.
‘It’s true that GHG produces cooling in the upper part of the atmosphere.’
It’s not just in the upper atmosphere, though. It can also produce cooling at the surface too. For example, see:
How increasing CO2 leads to an increased negative greenhouse effect in Antarctica – Schmithüsen – 2015 – Geophysical Research Letters – Wiley Online Library
(URL: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015GL066749 )
‘Though, I wouldn’t personally call this an “anti-greenhouse effect”….’
I think you need to take up the question of nomenclature with the planetary physics community, as the term has been in common usage for over a decade there.
‘….because it doesn’t in any way contradict the principle that the planetary surface is warmed by GHGs.’
I think the paper I have just referenced above shows that it definitely does.
‘….these mathematics are easily dealt with, and are dealt with by every serious climate model.’
Are they really? Can you show us an example?
‘Even I could easily write a climate model to address this issue’
So you say, but without your actually writing one and showing it to us, we have no reason to believe you, do we?
‘(though I’m not sure there would be a point to it).’
I think the point would be to demonstrate to readers here that you know what you are talking about and are not just making it up as you go along.
Thanks for the Antarctica reference.
That paper explicitly says “It is important to note that these results do not contradict… the well-known warming effect that CO2 has on the Earth’s climate.”
I guess a more precise statement would have been:
I’m really surprised to read your statement “This potentially dual nature of GHGs makes for some impossible mathematics that are currently far beyond the power of any existing computer models to embody and resolve.”
I have trouble imagining why this “dual nature of GHGs” wouldn’t automatically be addressed by the “line-by-line radiative transfer models” which are routinely used as a part of climate modeling. For example, such a line-by-line radiative transfer model is used in your Antarctica paper. Here is another example of a (math-heavy) paper that does line-by-line radiative transfer modeling.
Would you be willing to say what leads you to conclude that there are “impossible mathematics… far beyond the power of any existing computer models”?
I assume you are aware that such disclaimers are sometimes required to get papers past the “peer review” censors for many publications. The paper stands on its own. Disclaimers are not part of the scientific content.
Yes, it does. And, by my interpretation, the paper does not contradict the thesis that GHGs primarily have a warming effect on planetary surfaces. It’s possible that the author’s disclaimer was sincere. Your mileage may vary.
Here is part of the problem in using an average over the whole earth for 24 hours. You and many others miss what happens when 1300+ watts is absorbed by the surface at a moment in time. One example is CO2 saturation at this higher value. How much radiation actually leaves the earth with the radiation this high. Another is the level of evaporation with this high a level? How is convection changed? How about clouds?
The sun only shines half the day. You have no math that describes the actual radiation and thermalization for real, physical insolation to the earth.
Here is a simple question your linear algebra and averages can’t answer.
What occurs with the first ray of sunshine in the morning? Is it stored, re-radiated, or allocated between the two?
Does your math solution provide any insight to physical reality?
‘(The Antarctica paper ) explicitly says “It is important to note that these results do not contradict… the well-known warming effect that CO2 has on the Earth’s climate.” ’
I’m not sure what point you’re making with this, Bob. Those results obviously do contradict the “well-known (greenhouse) warming effect” of CO2 in the Central Highlands of Antarctica, because what the authors found happening there was the opposite of CO2-warming, i.e. CO2-cooling.
Perhaps I should make it clear though, that I am not arguing against the existence of the greenhouse effect. I’m just trying to point out that the greenhouse effect has two possible modes of operation – a positive mode which is already widely known and a negative mode which is less well-known. The positive mode acts to conserve energy within the atmosphere by preventing, or resisting, or retarding its evacuation to space, and the other, negative one acting in the reverse direction to extract energy from the atmosphere and facilitate its evacuation to space.
Both these opposing effects are caused by the same GHG-molecules and only the different local environmental conditions in which GHG-molecules exist determine whether they will act in the positive mode or the negative mode and what their magnitudes will be. We are dealing with a vector-space here and we would need to know what the local parameters are at every instant for each locality in order to produce an accurate global model. But as yet, we have no means of observing or measuring the local parameters across the whole globe and no means of calculating them from established prior assumptions, even with the aid of radiative transfer models, either. That is one reason why I said “This potentially dual nature of GHGs makes for some impossible mathematics that are currently far beyond the power of any existing computer models to embody and resolve.”. There are many more reasons besides that one though.
But if, after reading this, you still think it should be easy, why not try and write such a model yourself and show us all how easy it really is? Who knows, you may surprise everyone.
The results contradict the idea that greenhouse gases result in warming (not cooling) everywhere.
But, that idea is NOT an idea is, to my knowledge, promoted by those who assert that the GHE is real and relevant. The idea is an oversimplified conclusion that some people might have inferred being claimed, but which has not ever, to my knowledge, been claimed.
I, for one, have only asserted that the GHE is real at the level of the global average surface temperature.
If Antarctica gets warmer, that doesn’t “contradict” this conclusion.
It’s just an example of a place where a phenomenon that holds globally does not always hold locally.
So, while I agree that what is happening in Antartica may be different, an “Anti-GHE”, if you insist, it does not “contradict” the GHE.
* * *
Thanks for unpacking part of why you think the math is likely to be complicated.
The GHG-molecules themselves don’t have different “modes” of operation. They always process radiation in a consistent fashion.
What radiation emerges from a packet of mixed gas, and how its temperature will change, is a well-understood function of the temperature of the gas and the radiation incident on that packet of gas.
Whether that consistent operation results in net warming or cooling somewhere in the system is an emergent property of the system as a whole. It’s not a matter of the GHG-molecules behaving any differently.
Most of what you say is an argument about the limitations of any GCM computer model, namely, that the initial conditions and boundary conditions are not fully known.
I don’t know why you assert that we have “no means of calculating them from established prior assumptions, even with the aid of radiative transfer models, either.”
My first reaction is “of course we do.”
Computer models typically divide the world into a grid of cells, and model the state variables inside each cell and the flows of radiation, air, water vapor, and heat through each boundary of each cell.
One sets up boundary conditions and runs the model. After a certain transition period, the models tend to come into equilibrium, with some chaotic “weather” behavior mixed into the overall “climate” behavior. If one does enough runs, one can average out the “weather” behavior and one is left with the statistics of “climate.”
If one is particularly focused on the radiative aspects, often a one-dimensional model is used in which one looks at a vertical profile through the atmosphere, and considers the radiative transfer on a wavelength-by-wavelength basis. The math for this is a little complex, but very well understood.
Your Antartica paper relies on the results of such a computer model.
So, I remain puzzled about why you think the math is so intractable.
Unfortunately, there is a big difference between something being conceptually easy, and it being easy at the level of not taking much work.
The bigger problem is, there would be no clear purpose to it.
Currently my only motivation would be to demonstrate that it’s not “intractable.” There’s a limit to how much effort that motivation alone could justify.
I don’t really understand your assertion, so I don’t know what would be taken as disproof of it. Even if I invested the effort in building a model, I don’t know what the bar would be that I would be trying to exceed.
I’m guessing any effort would be better spent trying to understand what you’re concerned is “impossible.”
‘The results contradict the idea that greenhouse gases result in warming (not cooling) everywhere.’
No, they contradict the idea that greenhouse gases result in warming (not cooling) everywhere at the surface and in the lower-atmosphere, which is precisely where the nature of the greenhouse effect requires them to produce only warming by its definition as a surface/lower-atmosphere warming mechanism. This is the contradiction that I am seeing – a contradiction of the fundamental nature of the greenhouse effect as it is currently defined.
The authors of the Antarctica paper cited above seem to have resolved this contradiction by positing the idea of a ‘negative greenhouse effect’ to explain the anomalous cooling and I find that this resolution sits well with me, although that’s for more reasons than I have time to explain right now. (Anyway, I intend to use it instead of the more combative-sounding ‘anti-greenhouse effect’ in future, although it is basically the same idea as far as I can see.)
‘The GHG-molecules themselves don’t have different “modes” of operation. They always process radiation in a consistent fashion.’
I wasn’t meaning that they have different modes of operation internally. Only that their way of functioning in the surface/lower-atmosphere system has two different modalities that are symmetrically opposite to one another, whereby the direction of the net energy-flow through the GHGs in each mode is opposite to what it is in the other, which causes the effect they produce in each mode to be the opposite of what they produce in the other.
[BTW, the GHGs aren’t just processing radiation. They are also processing the energy of inter-molecular collisions as well. The GHE is far more complex than it is usually given credit for.]
To my saying:
“We are dealing with a vector-space here and we would need to know what the local parameters are at every instant for each locality in order to produce an accurate global model. But as yet, we have no means of observing or measuring the local parameters across the whole globe and no means of calculating them from established prior assumptions, even with the aid of radiative transfer models, either.”
you say:
‘Most of what you say is an argument about the limitations of any GCM computer model,…’
Of course it is, because a GCM is what you will end up having to construct. And the essence of my argument is that you do not have enough information about the real world climate system to be capable of constructing a model whose own behaviour will accurately reflect the behaviour of the real-world climate system. Furthermore, you currently have no means available to you to acquire the necessary information either.
‘I don’t know why you assert that we have “no means of calculating them from established prior assumptions, even with the aid of radiative transfer models, either.”
My first reaction is “of course we do.”’
What, you mean that you’re able to calculate all the local-scale information that you need which you can’t get from observation and then integrate all that into a grand unified model of the real-world global climate system that behaves just like the real thing and enables you to make accurate predictions of future climate states that can be checked and tested against observable reality in real time? Of course you can! (Laughter.)
‘Computer models typically divide the world into a grid of cells, and model the state variables inside each cell….’
Yes, but you don’t even know what all the state variables actually are, let alone what their values might be in each cell.
‘….After a certain transition period, the models tend to come into equilibrium, with some chaotic “weather” behavior mixed into the overall “climate” behavior. If one does enough runs, one can average out the “weather” behavior and one is left with the statistics of “climate.”’
And then all you will have is a probabilistic, descriptive model that has zero, or close to zero predictive skill because it does not contain enough information about the actual behaviour of the real-world climate system and the laws that govern it.
‘If one is particularly focused on the radiative aspects,…
….The math for this is a little complex, but very well understood.’
It is not enough to understand ‘the math’ very well (in your own opinion). You also need sufficient real-world information to base your model upon if you want it to reflect reality with sufficient accuracy to be useful to anybody. Suppose you were an artist who had been commissioned to paint someone’s portrait. Wouldn’t you need to observe your subject closely, deeply and in considerable detail before you lifted your brush to begin? And wouldn’t you need to keep your subject under scrutinous observation as you went along too, so as to keep checking that you were painting their portrait accurately and correctly? Or could you simply calculate what you think their face should look like without ever having seen them and then paint that instead? Substitute the words ‘model’ for ‘portrait’ and ‘global climate system’ for ‘subject’ in this analogy and that, I think, is what you are saying you can do and do it easily too.
‘Your Antartica paper relies on the results of such a computer model.’
Not entirely. The authors also obtained the same results independently from satellite observations using spectral analysis. If they had not done that but had based their conclusions solely on their radiative transfer model calculations, their results would not have been verified empirically and would have been scientifically worthless.
‘So, I remain puzzled about why you think the math is so intractable.’
Well, I hope this reply has helped to dispel at least some of your puzzlement over that, Bob. But whether it has or not, I’m afraid I have run out of time to discuss it any further, so I must bid you farewell now and give you my thanks for being such an urbane and earnest correspondent. I wish you good luck with any climate modelling adventures which you may care to undertake in future.
You are seeing a contradiction to what you have (incorrectly in my view) assumed to be the definition of the GHE.
I have never seen a definition of the GHE that asserted that GHGs should warm the surface everywhere.
To the contrary, I’ve frequently seen disclaimers that some places would be warmed, and some would be cooled, but on average the surface of the planet would be warmer.
To me, it sounds like the generic arguments made against GCMs.
I see nothing in what you’ve written to indicate that the radiative aspects are any more “intractable” than any other aspects of such modeling.
May you be well, and thrive.
Hi Bob. I’m back again after having dealt with the things that were urgently demanding my attention. I can’t say how long this happy condition will last though, so this is just a whistle-stop response to your last comment to me.
‘You are seeing a contradiction to what you have (incorrectly in my view) assumed to be the definition of the GHE.’
You may be right. To tell the truth, it seems to me that there are as many different forms of definition of the GHE as there are dictionaries and encyclopaedias to define it. (For example, see here.) Out of the definitions that I’ve seen so far, the Merriam-Webster definition comes closest to the one I had in mind. That definition looks typical of the genre to me in that it only refers to the idea of surface-warming being caused by “atmospheric gases” and not at all to any ideas of surface-cooling.
What is the correct definition of the GHE in your view?
‘I have never seen a definition of the GHE that asserted that GHGs should warm the surface everywhere.’
I don’t know what definitions you have seen, of course, but I think the idea of universal surface-warming follows logically from Sir John Houghton’s definition of the nature of GHGs as gases which are relatively transparent to incoming shortwave (SW) solar radiation and relatively opaque to outgoing longwave (LW) radiation emitted from the surface, whereby some of the outgoing LW radiation is absorbed by the GHGs and some of its energy is redirected back to the surface. Thus, by that definition, GHGs function as a surface-energy recycling-mechanism which only adds energy to the surface and never subtracts energy from it, thereby only ever causing warming at the surface and never cooling anywhere. Since the GHGs are spread throughout the atmosphere, they surround the surface and act upon it at every point and must, therefore, produce warming at every point and never produce cooling at any point accordingly.
This initial surface-warming resulting directly and immediately from the recycling of surface-energy by GHGs is the primary greenhouse effect at the surface (again, according to all the definitions that I have seen to date). However, it can cause secondary, knock-on effects, which may including localised cooling phenomena depending on the character of the local surface where the primary warming takes place. If, for example, the primary warming was to cause an ice-sheet to melt, the resulting melt-water might disperse into a relatively warm area of ocean and cool it. One can imagine many similar examples of local cooling resulting, as a secondary effect, from the primary GHE due to the direct action of the GHGs on the surface. However, the Antarctica paper attributes the cooling observed there directly to the primary effect of the GHGs in Antarctica and not to any secondary effects of the primary greenhouse warming that may have occurred elsewhere.
Having said all that though, I am not concerned so much with the largely academic question of how the traditional definition of the GHE might need to be changed to accommodate the “negative GHE” as the authors of the Antarctica paper termed it, as I am with understanding the physical processes that are involved. Evidently, when the conditions on the surface and in the lower atmosphere are right for it, the normal, “positive” GHE that one would expect to find there is replaced by a “negative” one which works effectively in the opposite direction, so that instead of recycling outgoing surface-energy back to the surface and thereby warming it, the “negative” GHE effectively accelerates the removal of energy from the surface and thereby cools it.
Why does this happen when it is the same GHGs that normally produce warming at the surface as now produce cooling? Only the environmental conditions in which the GHGs are operating are different and therefore those conditions must hold the key that switches the GHGs between their “positive”, surface-warming mode and their “negative” surface-cooling mode. I think serious climate-modellers will want to understand that environmental switch and incorporate it into their models. Doing so may look easy at first glance, but that could be because one is simply overlooking all the difficulties. Until you actually attempt to do it, how can you know how easy or difficult it really is?
I suspect the explanation of the physics is quite simple.
On most parts of the planet, the surface is heated by insolation from the Sun, and that heat then escapes to space via thermal radiation. If the atmosphere slows the flow of this thermal radiation, then that increases the surface temperature.
However, in the polar regions, the average insolation is quite low. There isn’t much solar energy going directly to the surface which is available to be “trapped” by GHGs.
In these regions, the average surface temperature is much warmer than can be accounted for by insolation. This is because the surface is significantly warmed by descending air currents that bring in air which was warmed at lower latitudes. (Warming ocean currents also play a role, particularly in the Arctic.)
However, as the concentration of GHGs increases, that increases the ability of these warm air currents to cool before they can reach and warm the surface in these polar regions. This leads to the polar surface being cooler than it would otherwise be.
In other words, GHGs do two things: they “trap” heat which has already reached the surface (via “recycling of surface-energy”), and they cool the upper atmosphere.
Over most of the globe, which is primarily warmed by insolation, the heat-trapping effect is more important.
However, in the polar regions, which are signifiantly warmed by warm air transporting heat from other parts of the globe, the “cool the upper atmosphere” effect becomes more important.
Note that the Arctic and Antarctic regions are somewhat different in this regard, in that the Arctic Ocean experiences much more warming from warm ocean currents (again, transferring heat from lower latitudes) than does the Antarctic continent.
Those ocean currents may dominate heating of the Arctic, and will act a bit like insolation, in that they bring heat to the surface, which can then be trapped by GHGs.
* * *
If there is a tendency for increased GHGs to cool the Antarctic region, on average, one might wonder how this could be consistent with worries about ice melting?
The answer likely lies in seasonal temperature variations. In the winter, when there is no insolation, then I would expect GHG atmospheric cooling to make the surface significantly colder.
However, in the Antarctic summer, insolation levels averaged over a day are actually fairly high because of the long daylight period. So, in the summer, the “heat trapping” effect of GHGs may dominate.
Thus, increasing GHG concentrations could result in increased summertime heating (and associated ice melting), along with increased wintertime cooling. And, the way radiant balance works, more extreme temperature variations generally leads to a lower average temperature. So, the net effect would be lower average Antarctic temperatures, despite warmer summertime temperatures.
* * *
So, to me, the mix of GHE and anti-GHE (in your way of thinking) seems generally understandable and unsurprising, even without doing any “impossibly difficult” mathematical modeling.
I’m curious if these explanations make sense to you?
If the explanations I’ve provided are correct, then I would expect that the relevant physics (atmospheric circulation, radiant heat trapping, and radiant atmospheric cooling) would already be present in all of the more sophisticated climate models (i.e., GCMs and whole-Earth models).
Note that, in this instance, you’re not saying the definition says that “GHGs warm the surface everywhere,” you are simply making your own hypotheses about what you imagine “should” be the implications of the existence of GHGs. Those hypotheses are not inherent in the definition itself.
This brings to my mind the difference between a definition of a concept vs. the predictions of a theory.
The role of a definition is one of conveying the general essence of an idea, not to fill in all the detailed nuances or implications or prerequisites or qualifications of that idea.
The role of a theory is to make testable predictions about how the world work. Unlike a definition, a theory is likely to involve various nuances, prerequisites and qualifications, and to offer predictions that are not always easily summed up by a simple verbal phrase.
The term GHE is a colloquial concept that refers to certain emergent phenomena that arise from the complete integrated physics theory that describe situations involving heat transfer, particularly radiant heat transfer.
It’s not the job of any definition to make explicit all the details of when and how one will see those phenomena.
I don’t think any one definition is likely to address all needs. So, different definitions could be considered “correct” insofar as they serve the needs at hand.
That said, let’s see what I can come up with…
First, I might be tempted to define a generic GHE that is not limited to radiative effects…
The Generic Greenhouse Effect (GGHE) refers to: the tendency of matter receiving thermal energy to increase in temperature when increased “thermal resistance” reduces the efficiency with which that thermal energy can be transferred to a heat sink.
(The GGHE is relevant to real greenhouses, as well as to the atmosphere, an electrical resistor on a circuit board, or a house being heated in the winter time via a limited heat source.)
The Radiative Greenhouse Effect (RGHE) refers to: in situations where radiant heat transfer is one of the significant heat loss mechanisms, the tendency of matter receiving thermal energy to increase in temperature when the “thermal resistance” of radiant heat loss is increased via the addition of materials that absorb and re-emit, or reflect or scatter, thermal radiation.
While I rather like that definition in some ways, it doesn’t express things in a way that makes the idea of a RGHE particularly testable, insofar as it only refers to a “tendency.”
An alternate definition, which is testable (even provable, per my essay), but perhaps less satisfying in other ways, would be:
The (alternatively defined) Radiative Greenhouse Effect (RGHE’) refers to: The amount by which the average temperature of matter (receiving thermal energy and losing that energy to a heat sink) exceeds the average temperature which that matter would experience in the absence of radiative reflection/absorption/re-emission effects (with the rate of energy input and material emissivities being held constant).
My essay basically proves that a RGHE’ greater than zero is theoretically possible and then shows that Earth appears to currently exhibit a RGHE’ value of at least 24℃ (with the detailed value depending on estimates of emissivity).
I’m not sure if any of those definitions are well-suited to the purpose for which you want a definition.
Regardless, I come back to the point that it is not necessarily the job of a definition to express the detailed nuances of what a theory predicts.
So, even if a popular communication about science said “The GHE refers to the way that gases which absorb and re-emit longwave radiation lead to warming of the Earth’s surface”, I think it would be unproductive to nit-pick and say “that definition didn’t say the warming wouldn’t happen everywhere!” That’s an issue of ambiguity or imprecision in the informal definition, not an issue with the underlying theory.
“how can you not accept that putting more CO2 in the atmosphere produces warming?”
But it causes what % of the warming? That’s what’s not yet determined.
Please explain how Ice Ages occurred when there was 4000ppm – 6000ppm of CO2 in the atmosphere.
That will do for a start.
That is only half the story.
The planet goes into ice ages when CO2 is high, and exits ice ages when CO2 is low.
That is a problem for those that consider that CO2 drives temperature changes, and argue that more CO2 causes more warming.
No one has adequately explained this problem, and what switches on and off the so called warming effect of CO2.
@Bob Bentworth
If I am doubting the “GHE”, than it is not based on not knowing, but on knowing more than you do. Also it is not about the question IF there is a GHE or not, but rather what size it has and what the contribution of GHGs hereto is. And for that, we need to know the basics, that is we need to know them right and not make some erroneous assumptions, like you do.
No it is not. Learn the basic stuff..
https://www.greenhousedefect.com/what-is-the-surface-emissivity-of-earth
Btw… you might find this chart on reflectivity of water (or emissivity respectively) helpful.
Not helpful at all without units labelled.
Really, is that so hard to figure out? Reflectivity is a dimensionless number between 0 and 1, so there are no units anyhow. And of course it is wavelength on the x scale.
The point is, just in case no one realizes, that the emissivity of water is 0.91. That is hemispheric emissivity, while the 0.96 Bob quotes are only the emissivity to surface normal. Bob does not know, and he does not care, cause really he has not much understanding of what he is talking. And that is just one of many blunders in his “mathematical proof”.
Thanks for the reference. Interesting. I make no claim to being an expert on specific measurements.
If we accept the premise that the surface emissivity of the ocean surface is 0.909, then that would change my computed lower bound on effective emissivity to 𝜀ₑ ⪆ 0.864. So, the calculated radiative effective temperature would be Tₑ = 265 K (-9℃). That would reduce the warming that must be due to the GHE to about 24℃.
I experience distorting my name as disrespectful. Would you be willing to try to keep this conversation civil?
Sure, sorry sometimes the tone here makes me a bit harsh as well.
Anyhow, that is not where the trouble ends, Dr.
BWentworth. The other serious problem you have, and I know you are just quoting the usual stuff, is that a world without atmosphere would still have the same albedo, which however is largely made up by the atmosphere and its components.Now we could go the complicated way and try to strip Earth of these and those components (clouds, GHGs, aerosols..), and figure out where that gets us. But of course there is a much more simple path forward. We can simply ask what surface absorptivity and emissivity are. Again, there is some uncertainty. But with regard to water, both are well known.
Absorptivity is 0.936 and emissivity, as before, 0.91 (ok, 0.909 in my calculation). So we can calculate what temperature water would take on, ceteris paribus.
((0.936 / 0.91) * 342 / 5.67e-8)^0.25 = 280.6K
That figure will differ a bit once land and ice (rather snow) should be included. But over all the natural GHE or atmosphere effect is only in the 8K region. And as I am yet going to explain on my site, that is not even caused by GHGs but by clouds. There are a lot of serious issues with the “GHE”, and hardly anything is like it seems.
Where does this figure come from? That figure seems roughly plausible as a figure for surface absorptivity in the absence of any atmospheric reflection.
However, it’s a bit suspicious that the exact value 0.936 has been quoted as the average emissivity of Earth. There is no reason to believe that the SW absorptivity should equal the LW emissivity. The equivalence of absorptivity and emissivity is valid only in the same wavelength range.
You are misunderstanding what is claimed (in a way that people often do).
Nobody is claiming that “a world without atmosphere would still have the same albedo.”
Nobody is claiming that “a world without atmosphere” could not have an average surface temperate that exceeds the radiative effective temperature, Tₑ, calculated for a world with an atmosphere.
What is claimed is that a world with the same albedo but no LW-absorbing/scattering material in the atmosphere could not have an average surface temperature that exceeds Tₑ.
Nobody is claiming that you would achieve the condition being talked about just by removing the atmosphere.
What is claimed is that given the albedo the planet has, its temperature cannot be explained in the absence of the influence of the LW-absorbing/scattering properties of material in the atmosphere.
Consequently, it is largely irrelevant to confirming or refuting the claims of the GHE to examine the temperature of a world without an atmosphere.
You could look at such a world, but if you do, you need to calculate a different Tₑ that corresponds to whatever albedo you have assumed.
Alright, you got me! Fact is, I misquoted myself. And that figure has a little bit of a history on its own.
https://notrickszone.com/2020/09/27/plenty-of-physics-flaws-accumulate-into-a-huge-ghe-hoax-the-dark-secret-behind-surface-emissivity/
There is a couple of things to explain here. Based on n2 = 1.33 I calculated a reflectivity of 0.066 and an emissivity of 0.934 (not 0.936!). Note: this calculation excluded the extinction coefficient and thus was wrong for the LW range, but it still holds true for SW reflectivity (where it is negligible). Somehow I confused the 0.934 with the 0.936 Zoe quotes.
Then I still have no insight what her number actually refers to. Again, NASA has no good data on surface emissivity, due to all the restrictions named and I am unable to read the raw data. I assume it is only some data on land.. but I do not know.
Anyhow, 0.934 and 0.936 are not too far apart, and the consequences are not quite a game changer..
((0.934 / 0.91) * 342 / 5.67e-8)^0.25 = 280.5K
Well, yet there is very little meat on the bone here. Essentially what you say is, the atmosphere cools the planet and the GHE (or atmosphere effect) overcompensates this so that eventually there is even some warming. Again, the net effect of it is 8K.
“denying that the GHE is real seems to me to be just as wrong-headed as insisting that the Earth is flat.”
Ironic statement.
Moon scientists correctly split incoming radiation into outgoing radiation and subsurface conduction.
~340 W/m^2 -> ~90 W/m^2 + 250 W/m^2.
The moon appears to be ~200K on average (90 W/m^2).
Only people who believe planets are flat would ignore subsurface conduction. Flat things have no thickness.
Can you please address this?
Conduction to where? Has several billion years has not been sufficient for the Moon, Earth etc. to come to thermal equilibrium below the surface?
No. That’s why the moon is ~200K, and not the ~270K predicted by merely blackbody calculations.
Moon scientists know what they are doing. They don’t neglect subsurface conduction.
Zoe, as shown in this article, it is allowed by Holder’s inequality for the average temperature to be less than the blackbody temperature. However, it cannot be greater without greenhouse gases.
“Average” temperature must be less but that doesn’t account for differences in temperature. It is possible for the surface temperature to be higher than the blackbody temperature even though the average is lower even without GH gases.
This is what he says:
“Let’s consider the case where there are no LW-absorbing (or reflecting) materials in the atmosphere of the planet (or in between the object and space).”
OK. The moon is such a case.
Holder’s inequality doesn’t explain why radiation entering is not equal to that leaving.
He also tells you:
“The rate at which radiant energy reaches space must be identical to the rate at which radiant energy leaves the surface, if there is nothing to absorb or reflect that radiation.”
But he’s only thinking of an absorbing atmosphere. He’s not considering an absorbing surface that conducts below.
Holder’s inequality explains why using the average temperature (~200K) to calculate “radiation leaving” is an incorrect way of calculating this.
Radiation entering does equal radiation leaving, on the Moon.
I don’t explicitly talk about that, but that’s because the result is valid whether or not there is subsurface conduction.
Such subsurface conduction does affect the surface temperature, T, and the way that temperature varies over the course of a day or year.
However, the calculation I’ve done provides a constraint that must be satisfied no matter what heat transfer mechanisms are active below the surface and no matter what non-radiative heat transfer mechanisms are active in the atmosphere.
Zoe, I have always seen a flat earth portrayed as thick, not infinitely thin. Just think of the massive waterfalls depicted. I still want to know where all that water and sea life goes. And how on earth it gets replaced. And what is on the other side?
Thinking of this is very agitating. What is down there to pull all that water down? If you lived on a massive coin shaped planetary disk, how would gravity vary from the center to the edge? If you stood out near the ridge and threw a stone perpendicularly away from the surface, would it ‘fall’ towards the center? Wouldn’t all the water on each side form a hemisphere at the center? Couldn’t you walk along the edge? Or flip over to the other side?
I shudder to think about what laws of the universe could be derived from a flat earth as it is often depicted.
The biggest reason that the Moon is so cold (190 K on average) is because the temperature variations are so large (due to the long 29.5 day rotation period, small heat storage capacity, and lack of mechanisms for transporting heat between hot and cold places). When temperature variations are large, the fourth power of the mean temperature, ⟨T⟩⁴, ends up being much smaller than the mean of the fourth power of temperature, ⟨T⁴⟩.
The actual heat loss scales as the fourth power of temperature, ⟨T⁴⟩, and is ~340 W/m^2.
A heat loss of ~90 W/m^2 is what one would calculate for heat loss if one inappropriately calculated heat loss using the fourth power of a 200 K average temperature.
The 250 W/m^2 “discrepancy” doesn’t really require any explanation. Averaging the fourth power of temperature is the correct way of calculating radiant heat loss, and taking the fourth power of the average is an incorrect way of calculating the radiant heat loss. So, the difference between these doesn’t have much meaning. It is not the amount of subsurface conduction.
* * *
Subsurface conduction is much less efficient on the Moon than on Earth. (This is because there are no oceans on the Moon, and because there is little gas to mediate conduction between grains of regolith.)
Subsurface conduction is important insofar as it has a smoothing effect on temperature variations over the course of a rotation (i.e., a “day”). Reducing temperature variations increases the average temperature. That’s one of many reasons why the Earth is warmer than the Moon.
* * *
However, with regard to my essay, none of these details matter.
The result that I derived depends on the surface temperature, not on how the surface temperature gets to be what it is. No matter what heat transfer mechanisms are present (subsurface conduction, or convection in the atmosphere), the result I derived remains valid.
As helpful as this is, we are being told, even scolded and hectored that we must now implement material changes to our society on the speculation that human activity is causing harm. Harm to what extent? Unless and until we determine what the optimum climate is for our biosphere, and determine if any change is moving towards or away from that state, we cannot make make rational policy decisions.
You got me thinking about SI units and our insistence on living with Celsius instead of Kelvin. So many of our formulas are simple because we work in Kelvin. You could of course correct the equations. Just replace T with T-T0, where T0 is the temperature at absolute zero. (No need for a scalar for Celsius, but Fahrenheit would need one.)
It is really easy to come up with the wrong answer to physics and chemistry if one isn’t careful like the author.
Why do we feel the need to flip back and forth? Wouldn’t we be better off living in one world of units?
I of course still cook and shiver or sweat in Fahrenheit. But there is nothing magical about 32 and 212, or 0 and 100, so why not use 273.15 and 373.15?
Doing so would give a better perspective. A change from 21 to 22 seems proportionally much bigger than a change from 294 to 295. Same thing, just one looks bigger than the other.
Adiabatic heating is simpler.
While I have a basic degree in physics, I don’t claim to understand all the math. However, I have done some studies on the matter which raise significant questions as to how applicable the calculations are. I have also studied lectures about climate change available on DVD by scientists with far more education than mine, and they raise some serious questions.
One of the lectures talks about climate change, earth’s atmosphere, and how the Milankovitch cycles affect it. Those lectures give the temperature of our earth over many thousands of years along with how much CO2 it contains, and end up demonstrating that during major ice ages earth’s temperature goes down first, followed by a decrease in the amount of CO2 as the oceans change temperature more slowly and then absorb more CO2. See any good reference book for the reason why.
Then we had what is called the “climate optimum” about 6,000 years ago, when it was warmer than today and CO2 was lower, around 290 ppm. Along came humans, and after the “little ice age” in the 1600’s (which was the coldest earth had been for over 6,000 years) human emissions increase the CO2 to currently about 40% higher than during most of the 6,000 year warm period. We are still colder than 6,000 years ago. So where is the greenhouse effect? Why did we have the February cold spell so famously centered around Texas? Why do I keep reading about a cold spring in Europe?
My personal observation is that the greenhouse effect is easily overridden by the realities of our climate, and all the other things which affect it.
The De-Glaciation created more Atmospheric Water Vapor as GHG that didn’t become Precipitation Clouds, on top of just the melting as runoff – that raised the surface water of our oceans – that due to dilution lowered the CO2 level of the waters. Once this created a higher temperature during the HCO and global warming temperatures cooled the atmosphere has been fairly constant in the fluctuations of solar activities fluctuations of the Holocene. Localized temperatures do not seem to have an effect on global temperatures as other localities were warmer at the same time “Texas” was colder. Climate Change is a global occurrence and not a changing of weather patterns in localized areas.
Thank you for clearly demonstrating your lack of understanding of my post.
“One of the lectures talks about climate change, earth’s atmosphere, and how the Milankovitch cycles affect it. Those lectures give the temperature of our earth over many thousands of years along with how much CO2 it contains, and end up demonstrating that during major ice ages earth’s temperature goes down first, followed by a decrease in the amount of CO2 as the oceans change temperature more slowly and then absorb more CO2.”
(Okay I have a gripe to make. I wrote a long paragraph that because of a misspelled word, that I corrected with the spell-check and it made the whole paragraph vanish.)
When you apply the Milankovitch cycles (solar cycles) to this Holocene Interglacial it is the water content of the atmosphere that answers your own problems of warming and cooling cycles. Warming creates biomass that creates CO2 that gets sequestered during the cooling cycle to be released during the next warming cycle with a lag time of near a 100 years and the warming has already started creating more biomass long before that happens. Biomass is the sequestration of Carbon and Water in flora and fauna that only decaying and burning releases their Carbon and Water back into the environment.
You brought up “So where is the greenhouse effect? Why did we have the February cold spell so famously centered around Texas? Why do I keep reading about a cold spring in Europe?” that are localized occurrences and yet elsewhere on earth there were higher than average temperatures that were seen in the southwestern states that were drier than average – raging fires – and offset those colder areas that got Iced. But mostly it was the changed Jetstream that brought that cold front from the north to the mid west. Very similar to what happened in the LIA on a smaller scale.
If you have a problem with what I’ve wrote, point it out and give an explanation for it,
Explaining the greenhouse effect in purely radiative terms is difficult when the atmosphere and oceans are dynamic. All that really can be said is that the daily pulse of surface upward LWIR is intercepted from a direct journey to space by water vapour and so encourages the lapse rate to become superadiabatic for instability and convection to occur which cools the surface. It is true that more energy is being “trapped” in the lower atmosphere than would otherwise be the case, but if extra warmth at the poles can be called global warming then its source of extra warmth should be called global cooling..
CO2 is a bit player in all of this. Doubling of CO2 to 800ppm results in a decrease in radiative cooling of 3W/m2. Our yearly variation of solar flux due to our elliptic orbit is around 100W/m2.
The fourth power of the average surface temperature is always less than or equal to the average of the fourth power of the surface temperature. The author claims that this is Hölder’s inequality. It is not. It is Jensen’s inequality for the convex function x to the power four. It was proved in 1905 and published first in Danish in 1905 and then in French in 1906.
Interesting. It appears that Jensen’s inequality and Hölder’s inequality are closely related.
One proof of Hölder’s inequality relies on Jensen’s inequality. But, the first proof of Hölder’s inequality appears to predate the first proof of Jensen’s inequality.
Both inequalities are rather general, and both imply that “fourth power of the average surface temperature is always less than or equal to the average of the fourth power.”
It appears to me that either general inequality can be used to justify the special case of the inequality that I used.
I checked the original Hölder paper. Although not stated explicitly the inequality used by you easily follows from the paper. This raises the question about Jensen’s contribution. I think it is threefold. He identified the importance of convexity, his proof is very elegant and general, and it does not require the function to be twice continuously differentiable. Jensen also realized that a number of known classical inequalities all are a reflection of convexity. In recent years it has been shown that even Hardy’s inequality can be proven from Jensen’s inequality. This also applies to non-commutative generalizations for the parameter p in the interval (1,2] and under the trace for p > 1.
I forgot to mention that Jensen’s method easily generalizes to functions of many variables.
I understand and concur with the skepticism some regulars in this forum have for Wikipedia articles. However, it is my observation that the level of skepticism is roughly proportional to the amount of politics in the article. Sadly, claimant articles are heavily influenced by politics.
However, Hölder’s inequality and Jensen’s inequality are less affected by politics and the respective Wikipedia articles should not be immediately discounted.
Wentworth provided a link to the Hölder’s inequality article but I haven’t seen one for the Jensen inequality, so for convenience I will provide both here:
Hölder’s inequality
Jensen’s inequality
Some of the confusion stems from the fact that there are several inequalities named Hölder’s inequality. The one you reference in Wikipedia is different from the original paper referenced by Bob Wentworth. I also got confused and only discovered the difference when I read the original paper in German.
Color me puzzled.
Wentworth’s original post made a reference to Hölder’s Inequality, which was linked to a Wikipedia article. That’s the exact same Wikipedia article I linked to. Can you elaborate on what you mean when you say there’s a difference?
SB radiant emissivity increasing at the 4th power of T is I believe why the GHE reverses in the stratosphere where T increases with altitude. Radiant emissivity goes up faster with diurnal UV heating and probably with significant Holder’s Inequality driving localized heating (solar /noon/zenith on ozone) radiating back to space as LWIR in the dry thin air.
Thank you so much for this. I have understood on basic principles the green house effect for some time after a very helpful interchange with Jonova. The mathematical underpinnings are very helpful to have though I am long past considering myself a math wiz. I still think it unfortunate and confusing this is called a “greenhouse” effect as I believe it was proven early in the 20th century that greenhouses warm primarily through containment (prevention of convection) rather than differential passage of shortwave/long wave radiation through he glass (or in this case atmosphere).