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 @ 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” @ 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?
Add stars
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.