By Andy May
This post was updated 9/24/2021 to reflect reader comments.
The phrase “greenhouse effect,” often abbreviated as “GHE,” is very ambiguous. It applies to Earth’s surface temperature, and has never been observed or measured, only modeled. To make matters worse, it has numerous possible components, and the relative contributions of the possible components are unknown. Basic physics suggests that Earth’s surface is warmer than it would be with a transparent atmosphere, that is no greenhouse gases (GHGs), clouds, or oceans. If we assume Earth is a blackbody, then subtract the solar energy reflected, from the hypothetically non-existent clouds, atmosphere, land, ice, and oceans; we can calculate a surface temperature of 254K or -19°C. The actual average temperature today is about 288.7K or roughly 15.5°C. This modeled difference of 35°C is often called the overall greenhouse effect.
A blackbody is usually defined as a perfectly black cavity kept at a constant temperature. All energy that enters the cavity is absorbed by the cavity walls, and they emit exactly the same amount of energy, but the wavelength of the emitted radiation is not the same as the energy captured. Instead, the emitted radiation has a wavelength determined by the cavity temperature, which is held constant. The Earth is nothing like this. It isn’t black and both the atmosphere and the oceans absorb and redistribute solar energy, often the absorbed energy is circulated for a long time, even centuries or millennia, before it is reemitted. A blackbody absorbs and reemits energy with a delay of less than a second. Earth’s surface temperature is not constant, like a blackbody’s temperature, it varies a lot by latitude, altitude, season, and/or ocean depth. The Moon has a calculated blackbody temperature of 270K, no atmosphere or oceans, and an average temperature, at the equator and low latitudes, of around 215K, so even the Moon is not an ideal blackbody.
Some unknown portion of the overall GHE is probably due to atmospheric greenhouse gases (GHGs). These include, CO2, H2O, CH4, N2O, and O3. Dr. William Wijngaarden and Dr. Will Happer examine the likely influence of these greenhouse gases using the HITRAN line-by-line molecular transmission and absorption database maintained at Harvard University (Wijngaarden & Happer, 2020). We discuss Wijngaarden and Happer’s important paper in this post and refer to it as W&H. HITRAN stands for high-resolution transmission molecular absorption. The database compiles spectroscopic parameters that computer programmers can use to model the transmission and emission of light in the atmosphere. W&H use the database to model a hypothetical mid-latitude temperature and GHG atmospheric profile to derive a representative climate sensitivity to doubling the gases. We have previously written about the GHE and will not cover the same ground in this post, which is mostly about the W&H model.
Dr. Clive Best also studied the HITRAN database, but just for CO2 (Best, 2013). Best also investigated the effect of gravity or air pressure on Earth’s surface temperature and concluded that they must contribute something to the overall greenhouse effect but was unable to model the amount. According to the second law of thermodynamics, a thermally isolated atmosphere will reach a constant temperature throughout its height if entropy remains constant. For a closed system that does not exchange heat or work with the surroundings, entropy can only increase. Earth’s atmosphere is not closed, since it is being heated by the Sun and losing heat by radiating to space.
Also, gravity does positive and negative work on the atmosphere, it does positive work on air parcels that sink. The work causes their temperature to rise and it can cause their entropy to reduce. But, since reducing entropy means taking heat out of the system, a cooling effect, which is stronger? This constant battle of contradictory forces keeps the entropy per kilogram of air approximately constant in the troposphere. The entropy of the stratosphere increases with altitude due to warming by ozone and stronger ultraviolet radiation than the troposphere receives. As temperature increases, entropy increases and radiation emissions from the GHGs increase. The overall proportions of surface warming due to GHGs, and gravity-induced warming, if any, remains unknown.
As far as recent—past 120 years or so—warming is concerned, gravity has not changed. However, the CO2 added to the atmosphere has increased the surface pressure slightly, since CO2 is 50% denser than dry air. Measurements suggest that the total water vapor in the atmosphere has decreased slightly, but these measurements are disputed due to the quality of the instruments used. Water vapor is 40% less dense than dry air, so how much the surface air pressure has changed due to differences in these two important molecules is unknown.
In this post we will ignore the effects of gravity and surface air pressure, even though gravity causes the Sun to fuse hydrogen into helium and emit the sunlight that warms our planet. Trying to figure out how much gravity contributes to the overall GHE, and recent warming only gives me a headache, and it creates furious arguments in the comments. The reason for the furious arguments, and my headaches, is that it is a complicated thermodynamic argument, and no one really understands thermodynamics. So, we just acknowledge it must have some effect on the total GHE and leave it at that.
Gravity has no direct effect on radiation transfer, but since gravity determines how the air pressure changes with altitude, there is an indirect effect because the air pressure influences the density of greenhouse-gas molecules. Thus, it also has a large effect on their total capture cross sections that contribute to the opacity of the atmosphere. For cloud-free air, the radiation flux is determined by only two quantities, how the opacity of the atmosphere varies with altitude and how the temperature varies with altitude. W&H took the altitude profiles of both temperature and opacity from experimental observations. The HITRAN data is based on observations. It is not theoretical data.
Because Earth’s atmosphere is transparent to most solar radiation and the Earth’s surface is opaque, the surface absorbs twice as much radiation as the atmosphere. Per the laws of thermodynamics, a planet tries to emit as much radiation as it receives. If Earth emits more, it cools; if it emits less, it warms. The global average temperature of Earth varies about three degrees every year, it is just over 12 degrees in January and just under 16 degrees in July. The Earth’s temperature controls the type of radiation it emits, and it emits mostly in the thermal infrared. The range of emitted frequencies, plotted as wavenumbers, with units of 1/cm, are shown in Figure 1.
The frequency and the power emitted by molecules are determined largely by the molecule’s kinetic temperature. In Figure 1, if the atmosphere is transparent and contains no infrared absorbing molecules, like CO2, the 288.7K emission spectrum would look like the blue curve. The y axis in Figure 1 is the spectral flux, or the amount of energy passing through the top of the atmosphere per unit frequency, in this case frequency is expressed as a wavenumber, or the number of waves per cm. Mathematically, ѵ (frequency) is the inverse of the wavelength.
A perfectly transparent atmosphere would radiate all surface emitted energy according to the blue line in Figure 1. All the curves plotted overlay in the atmospheric window (“Atm window”) from 824 to 975 cm-1. In this window the surface radiation can go straight to space, so it is labeled 0 km. This means the emission temperature (as determined from the spectral flux) reflects the modeled surface temperature of 288.7K or 15.5°C. Other example departures from the ideal Planck brightness blue curve, are labeled with the approximate altitude of the emissions, based on their brightness temperature. At these locations the atmosphere below these altitudes can be considered opaque to surface radiation due to the combination of GHGs modeled.
The green curve is the computed spectrum with all the greenhouses gases present, in their current concentrations, except for CO2. The black and red lines are the computed energy flux for CO2 concentrations of 400 ppm and 800 ppm respectively. The area difference between the green line and the black line is representative of the CO2-caused warming from zero CO2 to today’s concentration of 400 ppm. The area difference between 400 and 800 ppm, is much smaller and will result in much less warming.
The marked altitude of 84.8 km, in the middle of the CO2 caused divot in the energy curve, means that the emissions at that frequency range, roughly 609 to 800 cm-1, come from that altitude. Below that altitude, CO2 blocks the radiation at those frequencies. In this critical CO2 region of the spectrum, CO2 is saturated and cannot block anymore radiation. 84.8 km is nearly the top of the atmosphere, very high in the mesosphere. Additional CO2 makes the divot a little wider though, as the red curve illustrates and the widening causes a bit more radiation at the edges of the enlarged divot to be blocked.
As CO2 doubles from today’s concentration, the radiation emission level moves upward at all altitudes. As it moves upward in the troposphere, if cloud cover does not change, the emission temperature decreases, and the amount of energy emitted decreases. Since less energy is emitted to space, Earth’s surface should warm. When the sky is clear, radiation fluxes can be calculated accurately, but the conversion to a temperature change can get complicated. Emission height is strongly dependent upon frequency, as Figure 1 shows, and an average emission height has little meaning, just as a global average temperature has little practical meaning.
But at higher altitudes, in the middle stratosphere, temperature begins to warm with altitude. The warming is due to an increase in ozone (O3) as shown by the dotted red line in the right-hand graph of Figure 2. The increase in unattenuated solar ultraviolet light with altitude also has a warming effect. This means as the emission moves higher, more energy is emitted. This results in cooling, and we see this effect at the bottom of the CO2 divot in Figure 1. The red and the black curves reverse their positions and adding CO2 causes cooling. The reason why is illustrated in Figure 2.
The left graph in Figure 2 shows the atmospheric temperature profile used for the W&H model. In the real world, the temperature profile varies a lot from location to location and with time, especially in the troposphere, but W&H use a single set of values that are representative of the “standard atmosphere” in the mid-latitudes for their model.
There is very little H2O above the tropopause and N2O and CH4, already minor greenhouse gases in the troposphere, also decrease. In the stratosphere ozone (O3) warming is dominant and temperature increases, until the mesosphere is reached where ozone decreases rapidly and CO2 cooling begins to dominate. At the top of the mesosphere, roughly 86 km, changes in the energy flux are negligible, so W&H call this the top of the atmosphere or TOA.
Convection is minimal above the tropopause, but in the troposphere, it provides about half of the total heat transfer from the surface to the tropopause. As Figure 1 shows, except for the atmospheric window, the lower troposphere (below 2.8 km) is opaque to Earth’s OLR, or outgoing longwave (infrared) radiation, except in the IR window. The evaporation of water transports much of the surface emitted thermal energy, as latent heat, to higher altitudes where it can be radiated away from Earth. Thermal energy emissions, released from condensing water vapor, begin to appear at the base of low-level clouds, and continue throughout the cloud. Clouds are a very important component of Earth’s cooling system but cannot currently be modeled, so they are not included in the W&H model.
Clouds are included in the IPCC general circulation models (GCMs), but the IPCC assumes the cloud parameters and impact, they cannot calculate them. The IPCC AR6 report acknowledges that “clouds remain the largest contribution to overall uncertainty in climate feedbacks (high confidence).” (IPCC, 2021, pp. TS-59). While researchers are trying to model clouds, we share their high confidence that clouds are the largest source of uncertainty in computing the impact of humans on climate change.
The W&H emissions model is a clear sky model and only accurate above the clouds and in areas where there are few clouds, such as the poles and over deserts. Clouds excluded, W&H do try and account for GHG warming feedbacks. They investigated three cases, fixed relative humidity with a constant tropospheric lapse rate, fixed relative humidity with a variable lapse rate, and fixed absolute humidity. The resulting climate sensitivity values are shown in Table 1.
W&H also compared their resulting emissions calculations for three specific areas, the Sahara Desert, the Mediterranean and Antarctica. The comparison is shown in Figure 3.
The intensity values plotted in Figure 3 are different than the spectral flux values given in Figure 1 by 1/pi. The spectral flux values are energy passing an elevation in all directions, the values in Figure 3 are for brightness or intensity measured by a satellite. The difference is just in the units, they both measure emissions from Earth. The red Planck brightness curves in the left graphs are characteristic surface temperatures for the locations indicated, 320K (47°C) for the Sahara Desert, 288.7K (15.5°C) for the Mediterranean, and 190K (-83°C) for Antarctica. Notice the CO2 and H2O emission temperatures in Antarctica are warmer than the surface in the atmospheric window, this means the air above the ground is warmer than the ground and that the GHGs are cooling, not warming the air.
Summary and Conclusions
In summary, W&H have provided us with a detailed and accurate emissions model that shows only modest warming (2.2 to 2.3°C), inclusive of likely water vapor feedback, but not counting the feedback due to cloudiness changes. Both the magnitude and sign of net cloud feedback to surface warming are unknown. Lindzen has shown it is likely negative (cooling) in the tropics, but outside the tropics no one knows.
The water vapor feedback to surface warming is also very unclear, Ferenc Miskolczi (2014) has written:
“As long as the Earth has unlimited water supply (in the oceans) with its three phases permanently present in the atmosphere and two phases on the ground surface, the stability of the planetary climate will be controlled by the equations [see paper, page 19]. These two equations, together with the Clausius-Clapeyron equation, will regulate the transfer of the latent heat through the boundary layer in such a way that the net amount maintains the planetary radiative balance.” (Miskolczi, 2014).
Miskolczi, and others have found that total water vapor in the atmosphere has gone down in the past 70 years, although this is questioned. The work by W&M on radiation emissions suggests that future warming due to GHGs will be modest. Speculation about the warming feedback due to clouds and changes in total water vapor is just that, speculation.
The results of the study are summarized in Table 2.
Table 2 shows that the main GHGs are CO2, H2O and O3, doubling the methane or N2O concentration changes the outgoing forcing by less than one percent. Due to the properties of water vapor, its atmospheric concentration is very unlikely to double, but if it did, it would only increase the forcing by eight percent at 11 km. Doubling CO2 only increases the forcing by four percent at 11 km.
The combined current 11 km and 86 km forcing values in the table are not the sum of the individual values due to overlap. It is very clear from this table that all GHGs are saturated and adding to the current concentrations will make very little difference. Doubling CO2 will cause the stratosphere to cool about 10°C, but the changes in surface temperatures from this model are all less than 2.3°C, as shown in Table 1. This is much less than the preferred IPCC AR6 value of 3°C (IPCC, 2021, pp. TS-57). Considering that the current net effect of clouds is cooling and it seems likely that total water vapor in the atmosphere is decreasing or staying flat, these results suggest we have little to worry about regarding increasing GHGs.
Download the bibliography here.
“Convection is minimal above the tropopause, but in the troposphere, it is the dominate means of heat transfer.”
The junk GCM modellers all parameterize (aka use many fudge factors) on all the important properties of convection, convective heat transport and water vapor physics (cloud formation) for a number of important reasons (such as unknowns are high and computation limits).
This model parameterization of water vapor physics is probably why the models cannot realize (or reprodice) an observed, higher-ordered, emergent property of temperature control by our vast tropical oceans via humidity and the evolution of small scale convection into roiling TRW and convective heat transport that arises on model sub-grid scales throughout the tropics and lower sub-tropics. The CMIP modellers all try to parameterize what they think (or want to believe) is happening, and then get (tweak in) an ECS above 3ºC (per expectation) and a massive “fingerprint” of CO2 induced warming prediction as a mid-troposhpheric hotspot in the tropics, The hotspot is a creation of the positive water vapor feed back amplification the modellers want (need) to see in the output. The predicted hotspot is missing in observational records (satellite and radiosonde-ballon data). The models get an F, for fail. Actual science would reject the underlying failed hypothesis of a strong GHE via strong tropical water vapor feedback. But in the climate scam world, a rejection of this is unacceptable, becasue then the scam would collapse.
Yes, the GCMs do incorporate a lot of hard physics such as the radiative transfer equations of a blue sky and Naiver-Stokes equations for viscous fluid flows. But all that hard science is tossed into a slurry of crap parameters, this is like some some real science tossed into a shit cake recipe of fakery and expecting the final cake to taste good.
Bottom line: The GCMs are crap science. They only exist to achieve a political purpose, a purpise which is to promote the climate scam on the public to push us to relinquish our personal freedoms in the name of climate piety.
Just say, “Hell no. *eF* the climate scam.”
With frosting, the cake doesn’t look half bad at first glance. Your explanation of what’s underneath is excellent.
MODS
Our new spammer is at is again!
Are you causing parking problems for your neighbors with your many visitors?
I assume you are implying a significant gender imbalance in said car drivers/visitors?
The way I look at it is that even if one has a perfect model (based on physics), if random fudge factors are introduced, then the output becomes unreliable and unusable! Computational limitations demand that subjective parameterizations be introduced, being effectively equivalent to random fudge factors.
“…GCMs do incorporate a lot of hard physics such as the radiative transfer equations of a blue sky and Naiver-Stokes equations for viscous fluid flows.”
And how viscous are those fluids? I’d say there aren’t a lot of hard physics in the GCMs if these don’t match reality.
One of the most blatant tweaks is the overestimation of aerosol effects. Right down their alley for massive regulation of such, plus gives them excuses for the lack of predicted warming.
Clouds are just another phase of water.
It is atmospheric water that matters not atmospheric water vapour.
The SST is thermostatically limited to -2C at the low end (sea ice) and 32C at the top end (convective instability and cloud persistence).
These thermostatic limits control the energy loss and uptake into the oceans.
Atmospheric water warms the surface in November, December and January but cools the surface for the other 9 months.
The error in the concept of “Greenhouse Gases” is that water exists in the atmosphere as a gas, liquid and solid. Overall atmospheric water provides a net cooling of 1.3W/sq.m. Sea ice provides a net warming.
It is interesting to look at the SST in the Arctic Ocean at the North Pole. It never goes below -2C. And yet there is certain times of the year when there is zero solar input. Simple observation that the sea ice retains the heat.
If there was no atmosphere, the average SST would be 17C. Atmospheric water provides net cooling while sea ice provides net warming. Other atmospheric constituents make up the difference if there is any.
In a few placs, SST exceeds 32 C.
Shallow areas, right? Like the Red Sea and Persian Gulf?
Yes, but the Red Sea is deep, with shoaling at its southern end.
SST would be better named OCEAN Surface Temperature.
Seas can have vast relatively shallow fringes where surface temps in calm periods regularly breach 32C.
The reason sea water does not cool below -2°C is that it is at a phase transition between liquid and solid. If the air is colder than -2°C, more ice forms rather than the existing ice cooling down. If the air is warmer or a warm current of water comes in contact with the ice, it melts rather than warming up. All this happens at -2°C for sea water and 0°C for fresh water. The energy causing the phase change of the ice or water is known as the heat of fusion for a solid/liquid transition. When melting ice, the heat input is converted into the energy required to remove water molecules from the ice crystal lattice and provide the greater kinetic energy and vibrational energy of these molecules as a liquid. Same effect when converting a liquid to a vapor, called the heat of vaporization. This heat per mole or mass is usually larger than its corresponding heat of fusion because the molecules of liquid require more energy to leave the liquid and become a gas. For example, the heat of fusion of water is 333 J/gram and the heat of vaporization at sea level pressure is 2259 J/gram. Water has an extraordinarily large heat of vaporization as compared to most organic compounds on a mass basis.
If a transparent atmosphere were to be static there would be no greenhouse effect. It would be acting like a solid and would become isothermal via conduction from the surface to the top and all radiation would leave from the top at the rate predicted by the S-B equation.
In reality it would not be static due to the operation of differential heating at the surface resulting in density variations in the horizontal plane. That inevitably leads to convective overturning.
Such overturning causes a temperature decline with height due to conversion of surface KE to atmospheric PE as one gains height.
That decline in KE with height sets up the lapse rate slope that governs the rate of convective overturning.
Any disruption of the lapse rate slope caused by ghgs or anything else just results in a change in the rate of overturning which serves to neutralise any warming effect because such a change in rate adjusts the timing of the return of KE energy to the surface beneath falling air so that it can then be instantly emitted to space from the surface.
So, ghgs have an effect on weather but not on temperature and the effect on weather would be far too small to discern from natural variability.
Slight clarification.
Radiation to space would all be from the surface but would leave from the top at exactly the same rate as emitted from the surface.
It follows that if one were to add radiative material to a static transparent atmosphere then the surface would become even warmer but then the upward pressure gradient force becomes greater than the downward force of gravity and the atmosphere will be progressively lost to space.
It is the introduction of convective overturning that enables an atmosphere to be retained regardless of the proportion that is comprised of radiative material because the rate of convection is infinitely variable within limits set by the lapse rate slope.
Sounds reasonable but can you explain an electric kiln? The outside temperature of the kiln is definitely not the same as the elements.
Not comparable.
Of course it is. Energy applied into the interior. The insulation is the ‘atmospheric skin’. Heat lost is from the outer skin of the kiln.
Your theory should be able to be answered in any situations. You can’t explain it so your answer to my question is ‘doesn’t apply’.
I can answer my question to you using your own theory.
I’m not a warmist but I suggest you find a way to explain your theories in such a way that can explain things apart from your own theory.
The insulation in your kiln convects? That’s the oddest kiln I’ve ever heard of. Perhaps that’s why Stephen Wilde stated that it’s not comparable. Go back and read what he wrote for comprehension… he’s right.
There is nothing more misleading in science today than our remaining use of the thermopile to determine our understanding of radiation. It should have gone out the door with its overturning by the Planck solution of ultraviolet catastrophe. Thermopiles and blackbody curves are classical physics; we live in the quantum age, we now have lasers and quantum explanations to the infrared. But these are totally ignored by both sides. If Tyndall had a laser-based Raman spectrometer, the thermopile/ thermoelectric based ‘IR spectroscopy’ compliment, he would have concluded all gases in the atmosphere absorb and emit.
I am currently rewriting my work, I am an amateur and I am slow, but I will get there, and I have experiments that totally refute anything to do with thermopiles. Let’s move on.
Here’s my old work. The Greenhouse Gases and Infrared Radiation Misconceived by Thermoelectric Transducers https://vixra.org/abs/1811.0499
My current experiment: http://www.fractalnomics.com/2021/05/refuting-greenhouse-theory-experiment.html
And my Raman spectrometer interpretation of the atmosphere model (image).
I have an experiment to conduct: to radiate pure N2 with IR light and measure (with the Raman CARS spectrometer) if there is an excitation/ heating.
I am going to need help with this, so get in touch.
I can’t help you but I wish you good fortune.
Amazing what can be learned when you don’t already know everything
Or if science is “settled”.
Why does (or does not) water escape from the TOA to space? Gravity?
High in the atmosphere, sunlight splits water molecules into H and O atoms. The former escape to space and the latter form ozone.
It does escape at the poles.
“If we assume Earth is a blackbody, then subtract the solar energy reflected, from the hypothetically non-existent clouds, atmosphere, land, ice, and oceans; we can calculate a surface temperature of 254K or -19°C. The actual average temperature today is about 288.7K or roughly 15.5°C. This modeled difference of 35°C is often called the overall greenhouse effect.”
Radiative power does not deal with average temperatures (strongly nonlinear). The earth has a rather wide temperature span. Is that accounted for?
Snutbil, No, Earth’s surface temperature variability isn’t accounted for in that model. You are quite correct, and it is one of the many reasons why the blackbody calculation of GHE is nonsense.
Thank you, Andy!
Which means, the much referenced temperature without GHG might/will be seriously wrong, as will the green house effect.
I have a rather strong feeling this “simplifcation” (along with others, e.g. ∆T = λ ∆Ftoa as mentioned recently by Willis) have implications ruining “basic assumptions” in the climate field. Leaving quite few cards in the house of cards standing.
I struggle with seeing any real world use of global average temperature. I does not exist as a physical parameter and can it possible be used for any calculations?
The climatologists believe they can resolve changes of 0.01K in air temperatures from their monthly averaging (anomalies)—they are fooling themselves.
You mean, the earth is a complex system of systems? That it cannot be modeled effectively by a single equation involving CO2 concentration in the atmosphere?
Bu .. bu .. but the warmunistas have been telling the world for decades that the earth’s climate is really simple – CO2 is the thermostat, period, and we need know nothing more.
Words to live by
Pat Frank has shown that the GCMs can be reduced to a linear equation where temperature is the dependent variable and CO2 is the independent variable.
Clyde, Isn’t it amazing that thousands of scientists and billions of dollars are wasted on GCMs that can be reduced to a simple linear function??
Why no one is screaming at the wasted money amazes me. Pat frank was correct. Actually, W&H’s results are better and more convincing, at least to me, than any of the IPCC GCMs.
Each of the GCM’s embodies its own unique mini-Climate Theory (with assumptions and operators differing from all the others). So how does it make any logical sense to average the predictions of many theories and expect the resulting average to represent reality?
We would never average out various field theories and then all agree that that average (understanding) was the truth.
Pat didn’t conclude that “thousands of scientists and billions of dollars” were wasted because the models could be reduced to a linear function of GHG forcings. His insight was that these forcings were insignificant compared to the much larger errors in other forcings, i.e., cloud cover, hence the models can not possibly tell us anything about the impact of GHG emissions.
Love that, is it a quote by someone?
Your imagined earth is the moon. Earth has 5.5 quadrillion ton atmosphere (nitrogen and oxygen). Insulating the earth with 728 watts of power. The moon illuminated side 130°C and -143°C on dark side. On earth tropopause is -62.1°C add 728 insulated pressure makes surface 1.6°C (no sunlight for 23° below 90°) or add sunlight for 23° above 0° equator (summer) the tropopause is -67.2°C. Add 728 watts insulated powered pressure (+210 watts from land absorbed sunlight) makes surface 18.43°C, 938 watts. Only one hemisphere can have summer at one time. This scenario northern hemisphere is summer. Do mean calculation earth isn’t really 15.5°C but more like 10°C. The earth temperature is less when southern hemisphere has summer. More reflected sunlight due to northern hemisphere land snow and sea ice (while southern hemisphere still has a lot more ice than the northern hemisphere summer minimum). Around 4°C in this scenario. I have data to back this up.
A prominent contributor to this site has stated that he does not believe in the thermal inertia in the climate system and claims that because the Earth is not cooling since solar activity has decreased, it proves that modern warming is not due to the modern maximum of the sun. That’s laughable of course, the thermal inertia of the climate system is witnessed every year with the hottest/coolest times of year occurring at the end of summer/winter respectively, not with the longest/shortest hours of sunlight.
Thermal inertia has longer cycles as well due to vertical ocean currents. This fall/winter’s upcoming La Nina could drastically decrease global temperatures as the heat built up during the Modern Maximum of the sun continues to wane.
The climate inertia is 340 watts per second per square meter. 5.4 x 10^24 joules as total ocean heat content. And 63°C x 1591 N(force) 728/3.1=234.8w-m2 compressing of air by atmospheric pressure. Or 938/3.996 (234.7w-m2) of which is radiation.
Earth is cooling due to La Nina and decreased solar activity. Latest sea ice record makes it very clear.
There is an even larger blunder with their mythical +35C from the purported GHG effect.
The surface area of the black body in their model is a hypothetical construct of classroom science that doesn’t exist – a perfectly smooth sphere with no mass.
In reality, the surface area of Earth is far greater than the number they use – orders of magnitude more. The planet also contains thermal mass and the area of the planet in direct irradiance builds up heat energy over the course of a day and over the course of a summer.
Energy balance on Earth is controlled by thermostatic process at the sea surface. Open ocean temperature limited to 32C but regulates to 30C. Sea ice prevents heat loss once water surface is at -2C. Look at the surface temperature of the water below the North Pole; held to -2C despite zero sunlight for months at a time.
Atmospheric water cools the surface on average but warms for November, December and January then cools for the other nine months.
Earth’s average SST would be 17C if there was no atmosphere. Sea ice would still contribute to retaining heat.
Why pull out one phase of water in the atmosphere and name it a “Greenhouse Gas”.when the solid phase in the atmosphere has a high influence on reducing the heat input?
The thermostatic processes that regulate the energy into and out off oceans are far more powerful than any nuanced radiative transfer through the atmosphere.
“Sea ice
preventsreduces heat loss once water surface is at -2C.Agree. Skin surface is what radiates and not the average of what is under the skin. According to reflectance data – ice radiates much less than water. There is a quantum jump in the difference.
Liquid water can never be cooler than -2C. It becomes solid ice. The “WATER” liquid surface is the key. All the SST data show the water surface (liquid) at the North Pole as -2C or warmer. That surface is an interface between liquid water and solid sea ice rather than liquid water and air.
The emissivity of the liquid water drops dramatically as the thickness of the ice increases.
Sea ice covers a significant proportion of the globe and it varies over time. How does “Greenhouse Gas” theory cope with the sea ice. The ice affects the heat transfer in and out of oceans where sea ice exists way more than the atmospheric gases above the ice.
Your operative word was “prevents.” I was only pointing out that it was imprecise.
and has never been observed or measured, only modeled
Not true! for example we have 50 years of observation of atmospheric backradiation, of satellite measurements of outgoing longwave radiation and other direct measurements.
Griff,
Measuring radiation on the surface or by satellite is not measuring the GHE. It is just a measure of flux.
Andy:
This has always puzzled me.
Just how do sceptics propose that the GHE be measured ?
Serious question.
Anthony, Which definition? You have to ask a precise question to get an answer. Do you mean the overall GHE? With a transparent atmosphere or no atmosphere?
Do you mean the enhanced GHE, the impact of additional CO2 or additional water vapor molecule by molecule?
Or maybe you are referring to the delta net radiation (incoming-outgoing).
The problem with GHE is it means something different to everyone who uses the term.
I think W&H did a very good job of providing a consistent, physically correct, definition in this paper and I applaud them for it.
We will never get anywhere in this debate until the terms are defined properly. This is where the IPCC has fallen down the most.
Why is it up to sceptics to come up with a way to measure GHE. Isn’t that up to warmists to prove their point?
“… doubling the methane or N2O concentration changes the outgoing forcing by less than one percent. …”
And a short Google search (first one out the box) on methane in the News turns up this phrase:
Methane is 86 times more warming than CO2 over a 20-year period. LINK
Methane is important, because the news media, climate scientists and the IPCC are essentially lying about it. The “…86 times more…” statistic is real but meaningless. The real comparison is the “… less than one percent…” change to forcing mentioned in the above article. Indeed, table 2 above shows methane to have the least effect of all Greenhouse Gases by a wide margin. It is not 86 times more powerful.
Some analogies: An ant can lift 86 times its own weight, a man cannot, therefore an ant is stronger than a man. No it’s not. A Piper Cub can fly 86 times further on a gallon of gas than a jumbo jet. The proper response to that is, “So what?” But the 86 times more powerful meme continues unquestioned year after year. People are never told, nor do they seem to ever ask how much methane will actually run up global temperature.
The lies are working, governments are increasingly writing regulations that will eventually have a negative effect on you and me. San Jose, CA for example has banned natural gas hook ups in new construction. This will expand in scope to include new and existing buildings everywhere. Here’s a LINK where you can read about that.
By the way, the 0.8 w/m² increase upon doubling CH4 looks to be trivial, but needs to be translated into temperature, so even I can understand what the real impact is i.e., Fill in the blank:
A doubling of atmospheric methane should
run up global temperature by _____ degrees.
Provide that answer to the crazies writing the insane regulations, and maybe a few will reconsider.
Thank you great points about methane
Thanks for the reply. Given that by mass methane is 86 times more powerful than an equal mass of CO2, and given that methane is on track to increase about 0.5 ppm by 2100 and by mass the corresponding equal mass of CO2 would be about 0.18 ppm, it can then be calculated how much an increase in CO2 from 415.00 to 415.18 ppm would run up global temperature (essentially zero), and multiply that by 86. It comes out to ~0.04°C.
The Global Warming Potential (GWP) numbers that have been published in the IPCC reports were probably designed specifically for methane. From your 11th grade chemistry the Gram Formula Weight of methane is 16 compared to 44 for CO2. Methane is the only Green House Gas (GHG) on the list that is less than CO2 and hence the only GHG that gets a bump up on the GWP number.
“86 times more powerful”
because CO2 is not a potent greenhouse gas.
That is on a molecule-by-molecule basis for a gas that is much less common than CO2 or WV. Methane is not as stable as CO2 and oxidizes, becoming WV and CO2.
Clyde.
When you read about the Global Warming Potential numbers in the IPCC reports, it says that it’s by mass, not volume. Molecule-by-molecule is by volume.
Each molecule has mass.
Comparing atmospheric CO2 and CH4 by volume and mass yields two very different answers. A review of your 11th grade chemistry and the Gas Laws is in order. Thanks for the reply.
It is interesting that your initial statement referred to mass, but then you followed up with estimate of an increase based on volume (PPMv). You were not consistent in your choice of units.
‘Comparing atmospheric CO2 and CH4 by volume and mass yields two very different answers.’
Of course it does.
We did that in Physics class grade 7.
Or, CO2 has 1/86 the GHE of methane.
If methane was the great end point of existence we all would have died when the permafrost thawed the last time
Or the time before
Or the time before that
Much warmer than now, permafrost melted, it simply got cold and froze again
Simple
Well, the first problem here is that if you actually calculate the intercepted energy from the sun the baseline temperature for Earth is 45.7°F. I would think that getting THAT number right to begin with would be very important. Source? NASA.
I would also suggest that you go read what the word “blackbody” means, as your paragraph including it is self-negating.
Prjindigo, According to Britannica:
“Blackbody, also spelled black body, in physics, a surface that absorbs all radiant energy falling on it.”
“The best practical blackbody is a small hole in a box with a blackened interior, because practically none of the radiation entering such a hole could escape again, and it would be absorbed inside.”
Sounds like what I wrote. You need to state your objection more clearly. If you object to the time gap between absorption and emission, that was first detected by Wood in 1921.
https://royalsocietypublishing.org/doi/pdf/10.1098/rspa.1921.0049
That Black Body Cavity (BBC) (ha ha ha ha) must rank as one of The Most Childish & Naive descriptions of the Emporia Wardrobe. EVAH
If you MUST invoke Positive Feedback, do be aware that somewhere is a much larger Negative Feedback keeping it in check
Likewise Emperor’s Clothes is the repeated, everywhere, use of the term ‘Earth’ and also ‘Surface’
The Surface is the soil, the water, the dirt or anything planted upon or growing out of same.
The Surface is NOT where thermometers are usually put
When the term Earth is used, concerning radiation, PLEASE define whether it is
That you are talking about.
Certainly yes there is No Lie, all those places are part of ‘Earth, but not any single one defines ‘The Planet Earth’
That is deliberate obfuscation, just as in BBC (both cases)
Deliberate Obfuscation is used by people who frankly, Don’t Know WTF They Are Talking About
To spot that is the most basic and simple inherited/genetic skill that we all possess = Sociability or First Impressions.
It is why Mr Trump, without knowing any great amount of Science, saw straight through it as A Hoax
And yes, it is not easy telling someone to their face they are talking out of their backsides and if you do, expect backlash
In fact, expect Trump Derangement Syndrome – which is exactly what we got
But in this modern world, the word ‘Trump’ is entirely superfluous.
What happened to our Sociability?
Just ask the girls, ponder on why they are ALL out there looking for boys with a GSOH when such a thing should be an intrinsic part of ‘boy’
Where did it go…..
And because they cannot find any GSOHs any more, have collectively gone on Baby Strike and increasing are sitting in the offices of lawyers.
With sour faces, firmly crossed legs and leveling charges of Unreasonable Behaviour against husbands and soon to be ex, boyfriends.
Got to be one of the biggest understatements of all time. So far to date.
Climate Change is symptomatic of something much bigger and much more scary..
Since you’re critical of a whole lot things in that screed you might consider the use of acronyms that the reader has to look up in order to understand exactly what it is that you are trying to say.
GSOH = Good Sense Of Humor. Only I had to look it up. And considering where the Google search said that acronym is usually found, it looks like you spend time perusing the internet looking for a romantic partner.
OK that was mean, but I’m tired of people who use acronyms because they think it makes them look smart and up to date.
Are you over 100, Steve?
I didn’t know what “GSOH” meant either, and I wasn’t willing to take the time to run it down. Therefore, I skipped most of what Peta had to say.
Many definitions are listed. Teenage slang is not part of everyone vocabulary.
ROFLMAO! Oh Steve, you make me LOL!
TTFN
This is an apt time to reiterate what you just said. I was going to do so anyway. The earth is the earth and the atmosphere is the air. When using the word “surface” its traditional meaning is what you say. The rocks, soil, and oceans. Too many use the term surface to actually describe the atmosphere at the surface.
The surface (traditional usage) and the atmosphere are two different bodies when describing a thermodynamic system. The surface is a hot body radiating energy. The atmosphere is a cold body absorbing energy from the surface. They each have their own gradients and the gradients are affected by each other.
Another issue I never see addressed is H2O’s interaction with the sun’s near IR. Assuming a water vapor molecule can absorb no more one still has to address clouds, i.e., liquid water. Clouds can absorb a substantial amount of energy from the near IR turning water droplets back into vapor. Will this vapor last long since it is at altitude? I say it won’t, and it will subsequently re-radiate that energy. Some of that energy will be directed toward the surface but whether CO2 intercepts it before reaching the surface is an unknown. if so, it will raise the temperature of the atmosphere.
Very good Andy May! You recognize the complexities of Climate Science. My comment would be “He who studies radiation but ignores convection and the water cycle gets the wrong answer.”
Right, Andy has presented great points of uncertainty for a “The Science Is Settled” CAGW crowd to willfully ignore.
“The Moon has a calculated blackbody temperature of 270K, no atmosphere or oceans, and an average temperature, at the equator and mid-latitudes, of around 236K, so even the Moon is not an ideal blackbody.”
That is because the wrong method has been used to calculate it. Spreading the solar irradiance over the whole sphere results in an artificially high black-body temperature. Calculating the actual hemispheric heating and averaging that with the mean dark side temperature yields a reasonable global mean.
394K * 0.5^0.25 = 331.31K
minus albedo:
331.31 * 0.89^0.25 = 321.8K
and averaged with a mean dark side temp of 95K, is 208K for the global mean.
Earth’s sunlit side (at any given time) is cooler than the sunlit side of the Moon, but Earth’s dark side keeps so warm primarily because of the oceans rather than the atmosphere.
“208K for the global mean.” for the moon without an atmosphere.
Interesting that 208K (minus 65ºC) is very close to the tropopause temperature of Earth.
Ulric, There are many ways to compute the average temperature on the Moon, but none of them match the Moon’s blackbody calculated temperature. That is the point.
If you use the SB equation to computed a daytime temperature on the lunar surface you get 109C, fairly close to the observed 106C, but the nighttime temp of 90 to 95 means the lunar surface is storing a lot of energy. Blackbodies do not store energy.
Andy, I got close to the global mean with my method.
I calculated the mean for the whole sunlit hemisphere, not just the equator. 321.8K is about 48.7°C.
The mean dark side temperature of around 95K is NOT a lot of energy, it’s equivalent to about 4W/m^2.
Here is a link to NASA’s lunar surface measurements. Most of them fall between 320 and 360 in the daytime.
387695main_divinerb20090917-full.jpg (1280×720) (nasa.gov)
Anyway, estimates of the lunar average surface temperature vary a lot. There isn’t much data. The key point is the Moon is not a blackbody. If it were the nighttime temperature would be 2.7K.
No the key point is that dividing the solar irradiance by four and spreading it over the whole sphere is bad physics, and leads to an artificially high black-body temperature value. While diving it by two for the sunlit hemisphere only, and averaging that with mean dark side temperature, yields a good global mean temperature value.
Your point about black-body temperature illustrates that the dark side temperature is dependent on heat capacity. If the heat capacity was doubled, it would make the dark side much warmer, but not make much difference to the sunlit side, except nearer the terminators. Which is exactly why Earth’s global mean is much higher than the Moon, much more heat capacity to keep the dark side warmer.
Good point. Now explain it to the alarmists, they do not seem to understand this basic concept that heat capacity matters!
For Earth’s sunlit side, given 30% albedo, 6% Rayleigh scattering, and 16% near infrared absorption by water vapour, it equates to an equivalent black-body mean temperature of 12.5°C.
A greenhouse effect of +33°C on top of that is nearly as warm as the Lunar sunlit side.
You are saying that all blackbodies instantaneously re-radiate incident radiation? A blackbody the size of the sun releases all energy as quickly as a black body the size of a single molecule or atom? That implies infinite conduction rate, and violates the Einsteinian limit of the speed of light.
I think that a more probable model is a finite flux where the blackbody reduces its temperature over time, where the flux rate is a function of radius and thermal conductivity of the blackbody. Or, are you suggesting that because is it a blackbody, the energy conversions take place as a surface effect only?
That is precisely what a black body is, a surface only.
However, as a practical matter, we talk about an approximate or near-Blackbody. That is, we attempt to treat celestial bodies as having some of the emissive properties (albeit e < 1) of a Blackbody, yet, obviously, the moon and Earth have to have properties of a real solid, such as thermal conductivity and specific heat.
A blackbody is a theoretical construct. It is a massless, volumeless body that only has surface area and temperature.
It has its uses but you can’t add properties to it like specific heat and conductivity etc.
Certainly cleared some issues.
I too have made observations and this article has helped.
I present watts/micrometer. Not inversed. Shows how many watts at certain wavelengths.
20 watts (84km) CO2 emissions comes from this altitude (25 watts).
The earth doesn’t emit negative 128 Celsius (144.9K,20 micrometers 25 watts), only at that altitude 84km. CO2 temperature is -80°C 193K 78 w-m2 53 watts more than lowest level.
Every latitude from 90 to 0 when sun is at equator is 11.1 watts. Average of 938.51 watts (2021) (234.72 * 3.9984) was received from the sun. Average 231.39 watts was absorbed by the earth. 938.51-231.39=707.12 (310(solar)+74(absorbed by earth)+323(Atmosphere). Pressure 101325 can be calculated as 728 watts (63°C) @ 1°C multiplied by 1591 newton force.
Clouds not included in models blocks out 75% of solar energy. As clouds cover 74% of earth only 25% of the sun heats the earth. Reason the earth is 340 watts (5.4°C), measuring the earth from a academic website has CO2 forcing included increasing to 342.5 watts (5.8°C).
The 46700 (10 power 18) is 0.2% of atmosphere. It should be 9450 as 0.0412% (10.6 watts forcing).
Sorry to go off topic ,but how do i find the archives,I am sure that there used to be a way to access older papers by WUWT.March 2017 I am looking for “response tothe NYT primer on climate change^ .
Ed, The article is here:
https://wattsupwiththat.com/2017/03/18/response-to-the-new-york-times-primer-on-climate-change-short-answers-to-hard-questions-about-climate-change/
Article asks what does my reconstructed dataset say and what does it mean. That’s it. What was said is that CO2 emits at 84km, an altitude where at 625-714cm-1 (inverse or backward but still low energy) frequencies of radiation or 16-14 micrometers (low energy). Example over the summer the tropopause over Antarctic emitted radiation at frequencies at 631cm-1. Without extensive research and looking at the radiation flux in article. You may think was there a heatwave over Antarctic. No the higher temperature curve over such low energy is inverse. Backward (like reading words in a mirror). The radiation flux in watts/wavelength is no mirror. It’s real. Lower wavelengths (higher temperature). Higher wavenumbers (higher temperatures).
“The Earth’s temperature controls the type of radiation it emits, and it emits mostly in the thermal infrared. The range of emitted frequencies, plotted as wave numbers, with units of 1/cm, are shown in Figure 1.”
I always find this curve confusing and this particular one a little worse due to the superimposition of the imaginary green line for a non existent No CO2 scenario.
Perhaps someone, the author, can explain firstly how the radiation out is a smooth curve or can be a smooth curve when the emitting substances may not have an IR emission state at a particular temperature. I realize it is, I just do not get the specifics of how a substance can only emit at certain frequencies yet the radiation profile insists that it must do so to satisfy the energy in, energy out need.
I can imagine, for instance, a CO2 world putting out a lot more packets of IR if heated up more but how in the heck does it decide to put them out at frequencies or wavelengths it is not supposed to use?
This leads to the second problem, directly.
The amount of energy being put out is never greater at any spot and only ever dips at places leading to both overall energy out being less than what comes in.
Which is illegal.
And secondly does not make up for, as I said, the ability of something like a CO2 or H2O to put out a lot more pakets of energy at the one wavelength if it has enough energy to do so.
Is the blue line totally fictional and the real world non black body is putting out more energy at certain times and load and less at the other non emission wavelength gaps?
If so, why don’t scientists or people give the real line emission profile on top of the schematic one, if it is indeed schematic?
Third problem.
How can there be dips in the outward emissions at the absorptive frequencies if indeed the CO2 , for instance, almost immediately releases the same wavelength back to space?
Doing this and labeling it forcing implies that the atmosphere is indeed retaining energy and becoming hotter.
When this obviously cannot be the case.
The energy going out is the same as the energy coming in.
I understand there is an absorption going on but am missing the connecting piece.
If the absorption is real, ie less IR out at that wavelength, then something is happening to that absorbed energy that should be radiating out at that frequency. Either it is rising to a higher level forcing the CO2 [and H20 further out] to emit that energy at a higher distance and hence seeming lesser intensity per Sq meter.
The expansion of the hot gas below with the now cold gas above after emission falling.
Or it is emitting at a different frequency than what it is supposed to be emitting at.
Either way the model has to be wrong if it is claiming to be showing the actual amount of energy related to those wavelengths is missing a la Trenbath.
I have put a far bigger post up at Climate etc on this.
Basically
The atmosphere is warmer due to GHG, water and CO2.
Not because they trap or store heat but because they have to be at those temperatures to emit they radiation they receive.
Nitrogen and O2 molecules have a lot of motion which helps bump the IR emitting molecules. They are moving faster helping more heat being emitted but the surface where they came from is moving slower [is colder.
Everything is in balance.
There is no need for a TOA imbalance to put or store extra energy in a system [not that it can anyway].
The system is at the natural temperature it has to be to keep the incoming and outgoing energies equal.
The concept of retained heat is captivating, especially for GHG enthusiasts.
angech,
The dips are caused by the altitude of the emissions to space. The emissions at lower temperatures than the surface release less energy. Temperatures in the stratosphere can be at a higher temperature, but there are fewer CO2 molecules, so even there the energy emitted can be less.
A lot of the lost energy due to CO2 and other GHG absorption, due to lower emission temperatures or lower air density goes to warming the air.
Andy, I have had question about this for sometime. You say there is an element of radiation intensity that has to do with the number of molecules. It would seem that a portion of the “dip” could also arise from themalization of CO2 to N2 and O2. This energy is lost from CO2 when it occurs. This should then be a factor in reducing the energy at CO2’s frequency. This would have the effect of artificially reducing the height of CO2 radiation. I never see this addressed.
Jim,
In the troposphere temperature decreases with height. The power emitted from a CO2 molecule also decreases with temperature. So when energy is emitted from the surface or another CO2 molecule and captured by a CO2 molecule, if the receiving molecule is at a lower temperature, it excites the molecule so it has many more collisions with other neighboring molecules of all types. The collisions increase air temperature.
The lag between absorption and emission is long enough for millions or billions of collisions to occur. This dissipates some of the energy, then the rest is emitted, but with lower power than the molecule received.
This process works its way up to an altitude where an emission can make it to outer space. In the critical CO2 portion of the spectrum (see Fig. 1) the altitude where this happens is 84 km, almost at the top of the atmosphere – that is saturated!
I think it helps to look at the energies involved. A CO2 molecule weighs m= ~44/(6E26) or about 7.3E-26 kg. Its average kinetic energy is 3/2kT where k is Boltzman’s constant 1.38E-23 and T is temperature in Kelvin. So at 220K the energy is about 3E-21 J, and the average speed is sqrt(2x3E-21/7.3E-26) or about 285m/sec. Radiation is delivered and emitted by photons, whose energy is given by E=hv with v as the frequency in Hz, or equivalently hc/λ, where h is Planck’s constant 6.6E-34, c is 3E8m/s and λ is the wavelength – the main absorption bands for CO2 are 2.7, 4.3 and 15 microns (1e-6 m). So you are looking at photon energies of 1.96E-25/(2.7,4.3,15E-6) or about 7E-20J, 4.5E-20J and 1.3E-20J. The C=O bond has an energy of about 800k/6E23J or 1.33E-18J (so a photon of that energy or λ=~6.8E-8m could break the bond), substantially above the photon energies that serve to knock electrons into higher orbits that promote physical vibrations in stretching and bending of the CO2 molecule
Say the surface is 20°C 68F and at an altitude cooling stopped at -64C -83F. Or 30C 86F at an altitude cooling stopped at -71C 95.8F.
20 417 w-m2 9.89 micrometers 1011 wavenumbers
-64 108 w-m2 13.86 micrometers 721 wavenumbers
insulation 309 w-m2
30C 477 w-m2 9.56 micrometers 1046 wavenumbers
-71C 94 w-m2 14.34 micrometers 697 wavenumbers
insulation 383
CO2 -80C 78.67 w-m2 emitted radiation 15 micrometers 667 wavenumbers.
Where cooling has stopped is because gases at this altitude (11km) are absorbing at a higher warming rate (solar energy) than at a cooling rate(longwave energy). As cooling didn’t cool to CO2 15 micrometer band. How can absorption of IR from the surface of the earth happen.
Your perception is CO2 absorbs at the surface coz there is a gap and plank curve (blue line) has 14C 76F 287K temperatures. Not sure what the (X, Y axis ) numbers mean. That I’m trying to explain. And what inverse means. Why my explanation isn’t what your seeing. And whether you’ll understand.
angech,
All good comments. I’ll try and answer them all.
Wijngaarden and Happer did smooth all their curves for clarity. The raw HITRAN output is difficult to look at and make sense out of. See their discussion of their Figure 4.
I am also unclear why temperature determines frequency, but it does.
CO2 and other GHGs block radiation from the surface, by absorbing it at a cooler temperature. After absorbing the radiation the molecule becomes excited and has more collisions with neighboring molecules, warming the air around them. This happens millions or billions of times before they emit the radiation, but they emit it at a lower temperature (lapse rate controlled), so they emit less energy than they absorbed.
This process continues. In the case of the Main CO2 absorption frequencies (609-800) our current CO2 concentration blocks all emissions to nearly the top of the atmosphere, adding CO2 makes no difference.
CO2 has to absorb at higher wavenumbers and short wavelengths than what is emitted from the earth.
4.2 wavelength, 2380 wavenumbers. (these wavelengths and wavenumbers do not come from the surface).
15 wavelength, 667 wavenumbers (South pole lowest temperature -78°C. What is the wavelength and wavenumbers?
You are probably right, but I have no idea what they are. Download the full CO2 absorption spectrum from HITRAN and have a look. Attached is the absorption spectrum I got from HITRAN.
Good question. The very common use of ‘T to be fourth’ as determining radiated heat would seem to depend on the ability of the molecules to fill in an ideal radiative curve, at least approximately? Is there some thermodynamic reason why an atmosphere would tend.toward such curve shaping efficiency, or is it just lucky coincidence that the atmospheric composition seems to work that way?
I’ve had somewhat the same questions. Molecules absorb and emit at given frequencies. Exactly what molecules absorb high energy visible light? What molecules absorb near infrared? Why do you never see any outgoing energy at green. Green is either reflected or emitted by plants. If it is part of the incoming energy from the sun and it does reach the surface so it has to leave somehow. When looking at intensity, the amount of material emitting is important. Does this have an effect on calculating temperature?
Jim,
Plants absorb most of the red and blue light, and reflect green light and near-IR; the near-IR is reflected more strongly than the green. The blue and red are used for photosynthesis, albeit there is a fluorescent line in the red. Presumably, what isn’t reflected or used for photosynthesis is converted to heat, and then re-radiated as thermal-IR.
But where does all the green show up on outgoing radiation? At least over land, I would assume there is a large amount of green being reflected back to space.
Green shows up on Google Earth. The detectors for measuring earth temperature are specifically designed to not see visible light, reflected or emitted. We would be in a heap of trouble/ not be here if the earth was emitting in the green. Think of red hot/yellow hot iron.
It is my impression that the CERES measurements include all visible light, which includes green, when they attempt to determine an ‘albedo.’ That is, the green light is the reflected light in contrast to the thermal-IR, which is emission.
Jim, Nitrogen molecules absorb a lot of short wave radiation and the result is our blue sky.
I do understand that. That’s another question. Good absorbers are good radiators. As nitrogen is thermalized by CO2, Does it then radiate at visible frequencies? If so, how come it never shows up on radiation charts as outgoing energy emitted by earth?
My understanding is that it is Rayleigh scattering that is responsible for our blue sky.
Understand the spectrum.
Earth’s temperature.
Sea level 10 micrometers 1000 wavenumbers (16.8°C northern hemisphere summer)
11km 14 micrometers 714 wavenumbers (-66°C)
84km 20 micrometers 500 wavenumbers (-128.1)
Now imagine a huge radiator with water 85°C
How is the air heated?
20% radiation (186 watts)
80% convection (745 watts)
85C (8.09 micrometer wavelength, 1236cm-1)
Every cm away from the radiator gets cooler. Until room temperature is say 24°C (9.75 micrometers,1025 cm-1).
CO2 packets of IR at 15 micrometers, 667 cm-1.
Law of thermodynamic says a colder object cannot warm a warmer object. Or IR emitted from an object with less wavenumbers cannot increase the wavenumbers emitted by another object.
So earth is 16.8C emitting around 1000 wavenumbers and CO2 has less wavenumbers therefore isn’t going exceed what the earth is emitting. Therefore not increase the wavenumbers.
“Notice the CO2 and H2O emission temperatures in Antarctica are warmer than the surface in the atmospheric window, this means the air above the ground is warmer than the ground and that the GHGs are cooling, not warming the air.”
Umm…any relationship to the mysterious Antarctic cooling we’ve been told about here recently? How does this work in the Arctic winter?
¨In this post we will ignore the effects of gravity and surface air pressure, even though gravity causes the Sun to fuse hydrogen into helium and emit the sunlight that warms our planet. Trying to figure out how much gravity contributes to the overall GHE, and recent warming only gives me a headache, and it creates furious arguments in the comments. The reason for the furious arguments, and my headaches, is that it is a complicated thermodynamic argument, and no one really understands thermodynamics. So, we just acknowledge it must have some effect on the total GHE and leave it at that.¨
This guy did understand thermodynamics and radiation :
The Quantum Theory of Radiation A. Einstein (Received March, 1917) :
https://inspirehep.net/files/9e9ac9d1e25878322fe8876fdc8aa08d
I do realize what kind of reaction appeared here previously, but still, the headache of the entire economy collapsing because of green insanity far outweighs any mere argument.
Read this document also for a good mathematical treatise on how heat radiation works.
http://www.gutenberg.org/files/40030/40030-pdf.pdf
But the surface of Earth is NOT a perfect emitter. Especially in the far-IR range there is a substantial deviation of 12.5% on average with water, being the most abundant surface type.
Ignoring this reality introduces a large error, as it suggests GHGs like CO2 and specifically vapor were to mitigate a lot of radiation, which does not exist in the first place. The error significantly overstates the GHE of CO2, and vastly overstates that of vapor. The same is necessarily true for estimates on “forcing increments”, though vapor of couse is not considered a “forcing”.
The other problem should be quite obvious, if we consider what happens when the overlap between CO2 and vapor is allowed for, as in the above paper. Other than some 4 to 3.7W/m2 forcing for 2xCO2, the figure drops to only 3W/m2. It is a huge difference already and points out the significance of overlaps.
Excluding clouds from the get go means the largest overlaps, that of CO2 with clouds and vapor with clouds, are not taken into account. But these overlaps have huge impacts on the forcings and you get much lower figures if you take them into account.
https://greenhousedefect.com/the-holy-grail-of-ecs/the-2xco2-forcing-disaster
Most surface materials are diffuse reflectors. Water is predominantly a specular reflector (there is some diffuse reflectance from suspended sediment and plankton). One of the interesting things about specular reflectors is that the reflectance increases with the angle of incidence, and the higher the reflectance, the more spectrum of the reflected light resembles the spectrum of the source. Dealing with “surface normal” reflectance doesn’t provide the whole picture.
That is why I differentiate between surface normal, and hemispheric reflectivity (or emissivity respectively), and provide the data to all of you so that you get a glimpse on the “whole picture”.
The problem is that you are mixing logarithmic and non-logarithmic on the same graph, with no explanation why. To someone who knows what the graph should look like, it’s nonsense.
Tell us what you believe to know..
Yellow curve is 5778K. Orange curve is 288K. I don’t see how they can have the same amplitude. There seems to be something missing in your explanation(graph).
If one assumes that atmospheric CO2 is predominately of anthropogenic origin, it seems appropriate to ask if man has the capacity to double atmospheric CO2.
What on Earth is this “gravity induced warming” !?
I am sure a thermodynamics expert would look at this and laugh. This means the whole article is consigned to the bin.
Better to ask what on the Sun is gravity induced warming?
Well, gravity warms and compresses enough to millions of degree to allow nuclear fusion to start – it is then called a star.
There are quite a few of those gravity assisted fusion furnaces out there.
And as the CNO burning proceeds, gravity collapses the star quickly again giving a Supernova.
This red giant looks primed to go :
http://www.sci-news.com/astronomy/alma-atmosphere-supergiant-star-betelgeuse-04992.html
However, if the mass contracting was too small to initiate fusion, the gravitationally induced heating would have stopped, and then proceeded to cool, just as the Earth has done.
“However, if the mass contracting was too small to initiate fusion, the gravitationally induced heating would have stopped, and then proceeded to cool, just as the Earth has done”
Clyde, some interesting thought responses available in this comment.
First is there a confusion on gravity induced heating, one process, and fusion, a seperate process that actually produces ongoingheat generation by a different, and destructive mechanism.
If one thinks about it, as Andy put it, gravity decreases entropy of a system, ie increases the energy in a system.
At least it compacts or compresses the available energy leading to more molecular interaction and hence increased heat or energy.
While a meteor might be perceived to be cold and energy less without fusion there is still some minute heat generation occuring albeit with weak gravity being very weak heat.
At the centre of a large meteor the heat being generated by small molecular movement has to travel to get out so the centre should be warmer than the surface?
The earth is producing a lot of heat internally through gravity aided fission?
It is my understanding that while fission was taking place during early-Precambrian time, it is rare to non-existant today because the fissionable isotopes have decayed to a level the prevents a critical mass being achieved. On the other hand, nuclear decay generates sufficient heat that it prolongs the cooling time of Earth, leading to Lord Kelvin’s significant mistake in his calculation of the age of Earth.
Clyde Spencer
nuclear decay is nuclear fission.
From the scientific American article
Nuclear fission powers the movement of Earth’s continents and crust, a consortium of physicists and other scientists is now reporting, confirming long-standing thinking on this topic. Using neutrino detectors in Japan and Italy—the Kamioka Liquid-Scintillator Antineutrino Detector (KamLAND) and the Borexino Detector—the scientists arrived at their conclusion by measuring the flow of the antithesis of these neutral particles as they emanate from our planet. Their results are detailed July 17 in Nature Geoscience. (Scientific American is part of the Nature Publishing Group.)
Neutrinos and antineutrinos, which travel through mass and space freely due to their lack of charge and other properties, are released by radioactive materials as they decay. And Earth is chock full of such radioactive elements—primarily uranium, thorium and potassium. Over the billions of years of Earth’s existence, the radioactive isotopes have been splitting, releasing energy as well as these antineutrinos—just like in a man-made nuclear reactor. That energy heats the surrounding rock and keeps the elemental forces of plate tectonics in motion. By measuring the antineutrino emissions, scientists can determine how much of Earth’s heat results from this radioactive decay.
How much heat? Roughly 20 terawatts of heat—or nearly twice as much energy as used by all of humanity at present—judging by the number of such antineutrino particles emanating from the planet, dubbed geoneutrinos by the scientists. Combined with the 4 terawatts from decaying potassium, it’s enough energy to move mountains, or at least cause the collisions that create them.
https://en.wikipedia.org/wiki/Nuclear_fission
When common beta decay takes place, only an electron leaves the nucleus, and the atomic number is increased by one. That does not fit the usual definition of a nucleus splitting into two or more similarly sized nuclei.
Yes that is what happens initially. If there was no fusion, the star would continue contracting and giving out heat (adiabatic compression) until it could contract no more. At that point (equilibrium) no more heat would be produced and the “star” would cool. The fact that there is a pressure gradient per se does not produce heat at equilibrium. Compression only produces heat when active compression is in progress. When compression stops so does the heat production.
That is true for closed systems with an impermeable barrier.
Earth is not a closed system like this.
Entropy is constantly trying to get our atmosphere outa space (not even talking about solar wind etc.) and gravity is constantly providing a force against it. This force is translated to pressure.
Pressure is linked to temperature via the ideal gas law. Temperature is foremost kinetic energy and not radiation. The radiative theory of the GHE is mainly ignoring that.
Physicists often forget about entropy. Chemists don’t.
kzb,
I think you are confused about the second law. It only applies to closed systems. Gravity obviously decreases entropy and generates radiation, that is how stars work and how crystals form.
That answer shows how you misunderstand. Stars work because the contraction under gravity causes heating, until such time as fusion starts and an equilibrium is established.
Without fusion, the star would have to continue contracting indefinitely to maintain temperature.
In the case of a planet, without an additional energy source, the atmosphere would contract and in doing so would produce heat (adiabatic compression) until such time as the atmosphere liquified. But it has to be actively contracting to do so. The Earth’s atmosphere is not contracting and there is no net adiabatic heating.
kzb,
I see you did not read the paper. Here is the important bit you missed:
It will be absolutely negligible in warming. You are looking at maybe 0.01% change in the atmosphere mass, added over a time period of decades. The fact that you can posit this as a significant source of heating shows you really do not get it.
Hmmm, Methinks you are cutting your own throat. The Earth’s surface temperature varies 3 degrees C every year. The maximum (about 16C) is in July and the minimum is in January (12C) (Jones, 1999, Reviews in Geophysics). Yet, you claim 0.8C of global yearly warming since 1900 is significant? You are not much of an authority.
0.01% of 288.7 is .03, which is 4% of 0.8. Given that CO2 is 50% heavier than dry air, this number may be very conservative.
The point most people miss is we are talking about very small numbers, very small stuff can be confusing. Sometimes, insignificant, is just insignificant, like global warming.
You’ve just proved my point. The CO2 increase is roughly 0.042% -0.028% = 0.014%.
The gain in mass would be 0.02% by my calculation without any change in H2O concentration. And this is spread out over many decades. Any added compression heat from years ago has radiated away by now. It is not stored indefinitely. You have to look at it as a heating rate, not a total amount integrated over decades. The next stage is to calculate it in W/m2. That number will give you the fair comparison and I guarantee it will be negligible.
As above, you are forgetting about entropy trying to get the molecules out in space. It’s not a finite process with an equilibrium. It’s constantly ongoing.
If cooling would take place the ideal gas law requires that pressure goes down, leading to expansion of an atmosphere with the same atmospheric mass.
The only way to keep pressure constant is keeping the temperature constant.
Btw that is one of the reasons why dying stars first expand. They cool.
Pressure is the result of a mass of gas above you in a gravitational field. If the temperature increases the atmosphere will expand to a greater height above the surface, whilst becoming less dense in lockstep. The mass of gas above you does not change and to a first approximation the pressure will be constant with temperature (the strength of gravity does of course decrease with distance, but that is a small complication).
The temperature gradient of a tall column of gas in a gravitational field is well documented physics, apparently not understood by many. “Adiabatic lapse rate” is important in meteorological skew -T and ephigrams. The equations for adiabatic lapse rate don’t take into account radiative heat transfer between the warm bottom and cool top of the column of an IR absorbing gas column. Assuming convection as a primary source of heat transfer makes the calculations more “real world”.
https://journals.ametsoc.org/downloadpdf/journals/atsc/27/2/1520-0469_1970_027_0219_talrit_2_0_co_2.pdf
You can go back to 1964, Manabe and Strickler, fig. 4, to see curves showing calculated radiative and adiabatic equilibriums for the atmosphere.
https://www.gfdl.noaa.gov/bibliography/related_files/sm6401.pdf
DMacKenzie, Thanks, good links.
The temperature gradient of a THERMODYNAMICALLY ISOLATED tall column of gas in a gravitational field is ZERO, as first demonstrated by JC Maxwell about 150 years ago. This means that gravity itself does not create the gradient.
The earth’s atmosphere usually has a negative lapse rate because it primarily gains thermal energy (“is heated”) from the bottom and primarily loses thermal energy (“cools”) from the top. It is nowhere near thermodynamically isolated.
If the lapse rate introduced by this differential heating/cooling is larger than the adiabatic lapse rate, it is an “unstable” lapse rate, and convection starts to drive it back toward adiabatic. That is why we commonly (but not universally) observe lapse rates near adiabatic.
Ed, Good description. While a tall column of gas is isothermic, at least in my opinion, its temperature is set by the surface temperature under it.
If it is perfectly transparent, with no absorbing molecules, the temperature will last until the last molecule. But, this is not reality. I don’t think perfectly non-absorbing molecules exist.
“The temperature gradient of a THERMODYNAMICALLY ISOLATED tall column of gas in a gravitational field is ZERO, as first demonstrated by JC Maxwell about 150 years ago. This means that gravity itself does not create the gradient.”
Ed Bo.
Getting a bit deep here with the specifications.
Take away the caveats and what you have just said is
The temperature gradient of a tall column of gas in a gravitational field is not ZERO. This means that gravity itself does create the gradient.
–
While Maxwell is correct in a specific situation, well, he is pretty correct most everywhere, the fact remains that outside the thermodynamically isolated situations gravity can be considered by the lay person as a cause of heat production.
No it can’t. There can be no net production of heat by gravity in an isolated system. That is perpetual motion.
Ed,
Aarghh, as I said, not well understood. Lets say the atmosphere of a planet consisted of only one molecule, which hits a rock and is deflected upwards. That one molecule has a velocity which corresponds to a temperature of 1/2mv^2=3/2kT. You can actually calculate from high school physics the altitude at which its velocity will be zero thus its temperature absolute zero, due to climbing against a gravitational field. Of course ensembles of a huge number of molecules are always being jostled by their warmer neighboring molecules, so statistical thermodynamics equations must be applied, which is where the adiabatic lapse rate equation came from. I don’t know of anywhere Maxwell derived what you say he did.
And, for KZB, no gravitational “heating” is involved…the energy content of the adiabatic (zero heat transfer) column in the form of kinetic-thermal and potential-elevation energy is conserved as the molecules jostle up and down.
DMackenzie:
This is well understood by the scientific community, especially those who really understand statistical mechanics.
Maxwell expected equal temperatures at the top and bottom and in his book “Theory of Heat”, published in London in 1877, he writes (p. 320):
“The second result of our theory relates to the thermal equilibrium of a vertical column. We find that if a vertical column of a gas were left to itself, till by the conduction of heat it had attained a condition of thermal equilibrium, the temperature would be the same throughout, or, in other words, gravity produces no effect in making the bottom of the column hotter or colder than the top.
This result is important in the theory of thermodynamics, for it proves that gravity has no influence in altering the conditions of thermal equilibrium in any substance, whether gaseous or not. For if two vertical columns of different substances stand on the same perfectly conducting horizontal plate, the temperature of the bottom of each column will be the same; and if each column is in thermal equilibrium of itself, the temperatures at all equal heights must be the same. In fact, if the temperatures of the tops of the two columns were different, we might drive an engine with this difference of temperature, and the refuse heat would pass down the colder column, through the conducting plate, and up the warmer column; and this would go on till all the heat was converted into work, contrary to the second law of thermodynamics. But we know that if one of the columns is gaseous, its temperature is uniform. Hence that of the other must be uniform, whatever its material.”
Richard Feynman, in his classic lectures on physics, used a very similar proof. He considered it a trivial, obvious point.
The Feynman Lectures on Physics Vol. I Ch. 40: The Principles of Statistical Mechanics (caltech.edu)
The analysis for the adiabatic lapse rate is very different. If the magnitude of the negative lapse rate in a gravitational field is larger than adiabatic, the weight of the atmosphere above is not sufficient to suppress upward motion of the hot parcel below. This is called an “unstable lapse rate”, and convection starts, driving the lapse rate back toward adiabatic.
Smaller negative lapse rates, and positive lapse rates (temperature inversions) are “stable lapse rates” and can maintain, consistent with statistical mechanics analysis.
Bizarre logic, Angech. You agree that gravity does not create a gradient in an isolated column, but argue that somehow it does in other columns.
How do you explain the temperature inversions (positive lapse rates) that can occur at night, particularly in the months-long polar winter nights?
Angech – You say: “outside the thermodynamically isolated situations gravity can be considered by the lay person as a cause of heat production.”
I certain hope the lay person would not be so wrong. The power transferred to an object by gravity is:
Power = Force x Velocity
In the case of a solid object falling, the (vertical) velocity is non-zero, so the power is non-zero. But the atmosphere has already fallen, so its vertical velocity (overall) is zero.
This means the power transferred to the atmosphere is zero. This is basic high school physics!
Ed Bo
“Bizarre logic, Angech”.
I like to think laterally, Ed.
It causes me a lot of headaches, with others.
However logic has a chain to it which can be quite lateral as well.
You say,
” But the atmosphere has already fallen, so its vertical velocity (overall) is zero.”
You cannot pick and chose conditions to backwards fit a claim.
“The power transferred to an object by gravity is:
Power = Force x Velocity” seems OK.
However you claim “the atmosphere has already fallen” to justify your position or example.
Is the atmosphere lying inert ,cold, limp and lifeless on the ground?
Is the atmosphere you refer to that on the earth or that in the
“THERMODYNAMICALLY ISOLATED tall column of gas in a gravitational field ”
In either case I think you should conceded that for every fallen angel a thousand others are flapping their wings against gravity still.
“The atmosphere has already fallen” is a great way of putting it. It has. The fact that individual molecules are moving up and down is irrelevant, because it is the average of all molecules in the atmosphere we are discussing.
kzb
“The atmosphere has already fallen” is a great way of putting it. It has. The fact that individual molecules are moving up and down is irrelevant, because it is the average of all molecules in the atmosphere we are discussing.”
“The fact that individual molecules are moving up and down is not irrelevant”
It means they both contain energy [heat] and transfer energy [heat]
Yes but there is no generation of excess heat in the lower layer of the atmosphere by this mechanism. The atmosphere is not constantly producing new heat. That would be energy coming out of nowhere.
When you put your brakes on the friction produces new heat.
The heat comes from the conversion of motion into energy.
The sun causes the motion.
The sun heats the atmosphere, gravity pulls it back down.
It collides and creates heat from the gravity induced motion of the particles hitting each other.
The energy comes from the sun. Gravity converts some of it into heat as one of the ways it gets to go back to space.
There is more heat [excess heat ] you said in the lower atmosphere due to the effect of gravity.
Gravity per se does not make new heast, it allows a mechanism to generate heat from molecular motion.
Yes but the author and other people on here seem to think gravity does indeed generate new heat. Pleased to see you don’t thing this.
Ed Bo
Angech – You say: “outside the thermodynamically isolated situations gravity can be considered by the lay person as a cause of heat production.”
I paraphrased your initial statement.
A lay person could look at the heat in the lower atmosphere and conclude that it had been caused [produced] by gravity.
Higher up, less gravity, thinner air, less heat.
Lower down, more gravity, thicker air, more heat.
Now you can claim that the logic is wrong.
A lot of people disagree with you.
It certainly seems to have a validity on the surface.
Personally I would look at the power source first and then decide how that power was being transmitted
Exactly. This is absolutely basic and anyone who calls themselves a scientist should see it straight away.
The absorption band is saturated. This hugely important finding means that no matter how much additional GHG is added to the atmosphere, the warming effect will be tolerable. Climate change is not an emergency. COP26 is pointless with regard to climate. It was always about redistribution of wealth anyway.
Another important finding is that the different GHGs cannot be treated as separate, independent gases with their own GHG characteristics. In reality, there is a mixture. The bands overlap, water vapour is dominant because of its abundancy and individual gas contributions are greatly reduced. The band is saturated to all of the gases. We don’t have to worry about CO2, N20, CH4 or any other GHG.
The alarmists have no answer to this so they will ignore it.
As an aside, I have been speculating about the bigger picture and mention it here to be shot down if considered nonsense. Saturation is the explanation for those who reluctantly accept the GH hypothesis but cannot accept that global warming will fry us all. It would also explain why atmospheric CO2 levels of 8,000 ppm could exist in our history without destroying the development of life.
This got me thinking about the GH effect raising earth’s temperature from being too cold but saturation preventing the earth from becoming too hot. This must be linked to the amount of IR radiation, the path length (thickness of atmosphere) and concentrations of gases. The thickness of the atmosphere relates to the size of the planet and gravitational forces. Perhaps there is an ideal (goldilocks) condition which allows all these factors to produce the ideal, highly stable climate that supports life.
Another thought is that a greenhouse effect that warms the planet but not to a dangerous extent is surely a face saving outcome that everyone can accept and unite around? Well, maybe not everyone. The extreme alarmists will never give up their dream of Armageddon. I doubt if the modelers will back down either.
I think you will find the a greenhouse effect does not operate in a standalone fashion to warm/cool the atmosphere. If it was there would already be a mathematical solution. A coupled non-linear system means their are numerous variables that combine together to create a stable and liveable earth.
My understanding is that saturation leads to a widening of the wings of the absorption feature, and that is expressed by the logarithmic relationship between concentration and temperature increase.
I agree completely that all the absorbing gases have to be treated together, and not just focus on CO2. That is, if water vapor is responsible for most of the thermal IR absorption, the contribution of a doubling of CO2 is only a small fraction of the total IR absorption.
Andy:
Regarding Table 2, as the water vapor column amount is highly variable, what value was used for the calculation?
How much measured spectral irradiance data of the long-wavelength IR is available?
Monte,
The values used are plotted in Figure 2. Water vapor is the blue line.
Carlo, Monte
Regarding Table 2, as the water vapor column amount is highly variable, what value was used for the calculation”
As an aside the water in the atmosphere persists in a fairly constant percentage range related to the pressure and temperature of the atmosphere.
There are maps and charts of relative humidity
It cannot be over saturated for long. The excess [only] precipitates out as rain, the remaining air is saturated still.
When areas warm up without enough water underneath to saturate the air occur there is a slight decrease in the amount of water in the air temporarily.
Overall the amount of water [biggest greenhouse gas] in the global atmosphere stays the same but unlike the other gases the concentration in the air varies with the temperature at different local sites. It can still be used, and should be used in all GHG calculations.
LOL! I just read the old linked article by Willis “The Stell Greenhouse”. It perfectly describes his ill fated “understanding” of the GHE. And I was tempted to point out the logical fallacy, but then I thought this is so obvious, someone should have done that already in the comments. And indeed, “Anton Eagle” puts it perfectly:
Exactly! And that perfectly describes the impossibility of “back radiation” heating anything. Really it would mean free energy out of nowhere. And once you introduce this free energy and apply it consequently, it is not just a certain amount of free energy, but actually endlessly inflating free energy.
Ironically, if it would work, we would need no more fossile fuels and could rely on perpetuum mobiles instead, like the mythic “Manabe-Strickler” device 😉
Back radiation is a thing. However the fallacy come in when it is added to the original radiation in an ever increasing sequence. Think of the planet having two bodies, the surface of the globe (dirt, oceans, etc.) and the atmosphere as an insulator. This makes it a simple thermodynamic system. The “surface” radiates a given amount of energy, primarily at far infrared. The atmosphere works like an insulator, albeit with a multitude of different gradients and back radiates some of the absorbed energy. Think of an insulator made of an alloy with numerous different materials.
Let’s say the earth radiates 100 watts into the vacuum of space. It will take a certain time to cool depending on several factors but in the end it loses 100 Joules/second. Now let’s insulate it. The insulator will “back radiate” as it warms. Lets say it’s temperature causes a “back” radiation of 50 watts. What happens to the hot body? It absorbs the incoming 50 watts but keeps right on losing 100 watts for a gradient of net 50 watts. So does the cold body drive the hot body backwards up the gradient so it begins to radiate at 150 watts? No. But it does lengthen the time for “cooling”. Some folks want to say that the 50 watts adds to the already 100 watts but it doesn’t. Max Planck in his treatise on heat radiation calls this compensation. It is why insulation can not “add” heat to your house but only slow heat loss.
Let me say this is a terrible simplification of what goes on but it should demonstrate the fundamentals of heat transfer.
You are still stuck in the same fallacy. What you mean is insulation, which can attained in different ways. Stop the air from circulating freely, and you get a literal greenhouse effect, like with a car in the sun. Or coat something with a material of lower emissivity, will work as well. Anything that impairs the flow of energy (convection, conduction, radiation..) will work.
“Back radiation” will not.
You will notice that I called the atmosphere an insulator. An insulator can and quite likely will heat to the sources temperature at the boundary. However, the conductivity of the insulating material will provide a gradient to the cool side that inhibits heat transfer. In essence, the insulator gets warmer throughout its volume and because of low conductance, releases it at a slower rate to the cold side. This is why the atmosphere warms. However, it can never warm to a higher temperature that the source, the surface of the planet, so it can not make the surface hotter.
It is important to be accurate when the word “surface” is used. It can not describe both the land/oceans and the atmosphere. Most land temperatures are really a measure of the lower atmosphere and not the ground. There are colleges that do track the ground temperature at various depths, and it is quite different than the lower atmosphere.
Let me solve “The Steel Greenhouse” example. I think it is easy to see how it can not work the way Willis suggested. But how will it actually work?
Let us assume the shell had a very tight fit around the planet, so that any delta in radius would be negligible. Then the surface would emit 235W/m2 into the shell, until the shell is warm enough to emit 235W/m2 into space. Also it would emit 235W/m2 “back” to the surface. Big question: what happens now?
Will the surface receive 235W/m2 or original feed plus another 235W/m2 as “back radiation” and would this add up to a total of 470W/m2 energy budget? If so, we would end up with the same free energy dilemma already discussed.
In reality it is very simple. The surface emits 235W/m2 into the shell, the shell emits 235W/m2 onto the surface, which is a lump sum game. And that is what “back and forth” radiation always is.
The shell has two sides. It will emit half of 235W/m2 into space and half back to the surface.
E. S…..HEAT is fore radiation minus back radiation….so you are ‘sorta’ correct, back radiation doesn’t really ‘heat’ anything…the fore radiation does the heating…but, the back radiation is half the solution of the SB equation as to how much heat the fore-radiation can transfer to the cooler body…..
My money is on Jim G…
Willis analyzes the steady-state case in his Steel Greenhouse example. In the steady-state case, power inputs match power outputs exactly, and there are no more follow-on increases.
Anyone who has successfully made it through the first few weeks of an introductory thermodynamics course would realize this. It is apparent that you (and Anton) have not.
Excellent post.
Max Planck observed that for heat radiation and molecules to interact requires comparable dimensions.
High energy Gamma and X-rays have short wave lengths on the order of atomic and molecular dimensions and interact aggressively, sundering bonds and ionizing targets. (See attached chart.)
Lower energy UV with longer wavelength photons have only enough energy to displace electrons which then settle back and fluoresce by emitting lower energy visible photons.
Visible wavelength photons reflect/bounce back to human eyes or detectors. The spectral absorption lines produced by the unique molecular electron shells are similar to the crossover networks in stereo speakers that block/pass audio frequencies to the woofer, mid-range and tweeter.
Thermal IR photons are too long to interact with gas molecules and simple pass through.
When these thermal photons strike a solid surface, their radiative energy converts to kinetic/thermal energy raising the temperature of that solid. (Temperature is the KE of stuff.)
Those IR heaters mounted ceiling height heat the objects in their path below increasing those object’s KE and temperature. Those objects in turn warm the surrounding air through conduction/convection/radiation. (As discussed in my earlier Power Points.)
In the popular liter bottle experiments, the heat lamps directly heat the bottles which then warm the contents.
The Sun heats the Earth’s surface, the surface heats the air.
That CO2/GHG molecules even absorb/emit/warm from thermal photons is supported by neither theory nor evidence.
Nick:
I may be completely misunderstanding your statement, but from experience gained working for a company that manufactured trace gas detectors, I can confirm that of absorption of IR energy by certain gasses (including CO2, CH4, N2O, HFCs etc.) certainly does occur.
The detector is a broadband IR source followed by a narrowband filter (in the range 5um – 50um, depending on gas to be detected), a sample cavity then a pyroelectric sensor. Calibrated against a ‘standard air’ sample (N2 + O2), I can confirm that the sensor output falls in proportion to the concentration of absorbing gas in the sample.
I can’t reproduce the theory here ( Company I.P.) but I confirm that I have seen the evidence.
“That CO2/GHG molecules even absorb/emit/warm from thermal photons is supported by neither theory nor evidence.”
I would not propose the evidence in the link below as direct evidence, but it does indicate that, as Einstein theorized, matter can be created from photons. If so, it is not hard to conceive that there is some interaction, however slight, between IR photons and such molecules.
https://www.sciencedaily.com/releases/2021/09/210920152005.htm
“That CO2/GHG molecules even absorb/emit/warm from thermal photons is supported by neither theory nor evidence.”
Why do you continue to display your own profound ignorance here? 200 years of repeatable controlled laboratory experiments demonstrate that your statement is completely false.
Inexpensive commercial detectors as mentioned in Cyan’s response are an easy disproof of your claim.
We understand the theory very well too.
Nick Schroeder
“Visible wavelength photons reflect/bounce back to human eyes or detectors.”
This is not true.
Which should be an end to the matter.
First take any black body.
The visible wavelength photons are absorbed.
Nothing bouncers back to human eyes.
That is why a black body is black.
Second, take your human eye or detector.
How can it detect visible wavelength photons ?
Remember you just said they bounce of or reflect so the eye or detector could not possibly detect them.
The only reason they appear visible to you is because your eye absorbed them.
Nick Schroeder
“Thermal IR photons are too long to interact with gas molecules and simple pass through.”
Again not true.
You are confusing wave and particle theory for the convenience of your argument.
Consider an IR wave being emitted from a molecule how did something so big get inside there?
“When these thermal photons strike a solid surface”
A solid surface made of molecules too small for the IR wave too interact with, is that what you mean?
“That CO2/GHG molecules even absorb/emit/warm from thermal photons is supported by neither theory nor evidence.”
Nick, where do you get this sh!t from ?
Nick lives in a parallel universe that has different physical laws. He visits us occasionally.
“it seems likely that total water vapor in the atmosphere is decreasing or staying flat”
Nonsense. Closely correlates with temperature.
lgl, The RSS TPW is only over the oceans. To get global coverage you need to incorporate weather balloon data, which RSS ignores. More here:
Does Global Warming increase total atmospheric water vapor (TPW)? | Andy May Petrophysicist
One of the major problems with this study and its conclusions is that it only applies to areas of the earth with clear sky conditions. This is only a minority of the surface of the earth.
To quote from the following page at NASA:
https://earthobservatory.nasa.gov/images/85843/cloudy-earth
“One study based on nearly a decade of satellite data estimated that about 67 percent of Earth’s surface is typically covered by clouds. This is especially the case over the oceans, where other research shows less than 10 percent of the sky is completely clear of clouds at any one time. Over land, 30 percent of skies are completely cloud free.”
So, this study deals with perhaps 1/3 of the earth’s surface. At most.
Moreover, they acknowledge that there are areas of the earth where temperature inversions exist, which radically alter the structure of the temperature in the atmosphere – and to which their calculations do not apply.
Perhaps the best known area with significant temperature inversion is Antartica. However, there are other studies showing that major areas of the northern land masses also experience temperature inversions during the winter portion of the year. Such inversions are often associated with cloud-free conditions.
So the real picture is much more complex – and this leaves aside the impacts of convection, which is a major aspect of the transport of heat from the surface to the upper parts of the atmosphere, especially in the tropics.
A comprehensive study of the effect of increased CO2 levels would have to take into account these other conditions of the real earth.
All good points.
The science of climate change is settled, they tell us. Settled and driven by CO2. But we don’t understand the effects of gravity on temperature. We don’t include the effect of wind currents. No one understands thermodynamics. Clouds are poorly understood.
We do, however, have a good map of frequency related effect of individual GHGs. And we can model these well enough to match very closely areas where the factors that are not well understood are minimized. And, what do these limited models tell us? That the effect of CO2 on temperature is limited to a narrow band of frequency, overlaps with H2O, and is saturated in its effect.
Can we stop doing stupid stuff to make anything carbon related expensive now? Can we unsettle the science and get back to real scientific inquiry?
Andy- You say the term “Greenhouse Effect” or GHE is ambiguous. I’m not sure what is ambiguous about it. People often say the greenhouse analogy is inappropriate because the physics involved is somewhat different. I say yes and no. Both the greenhouse roof and the earth’s atmosphere are transparent to the incoming short wave, and when that radiation hits the ground, it is absorbed and causes the ground to heat up. I believe the greenhouse and the earth are the same in that respect. Once the ground is heated, it begins to lose that heat by radiation. The earths’ atmosphere impedes the loss of heat from the earth because the long wave energy being radiated is absorbed by the atmosphere, causing the atmosphere to warm up somewhat. But, the heat eventually leaves, it just leaves at a temperature higher than it would if the atmosphere were transparent to LW as well as SW radiation. The greenhouse which is also warmed by the incoming solar must also eventually lose the heat, heat and some is lost by radiation, and some by conduction. There may be convective heat transfer inside the green house, just as there is in the earth’s atmosphere, but ultimately all the heat leaves either by conduction or radiation.
As for only being modeled and not measured, if you mean we cannot get the temperature of the earth with an LW transparent atmosphere or no atmosphere. I supposed that is true, but we only have to look at the moon to see what happens to surface temperature without an atmosphere. What is the point of saying we cannot measure the greenhouse effect?
Tom,
The lower troposphere, especially the lower few meters are opaque at the CO2 and H2O frequencies, so in the general case the Earth loses the energy via convection, very little makes it to space via radiation until a high altitude is reached, as detailed in the post. Greenhouses warm by restricting convection, so do blankets and tents. Radiation plays no role at CO2 and H2O frequencies.
The very poorly defined GHE has us spending billions of dollars trying to fix a nonexistent problem. It cannot be measured and is ambiguous. W&H have proposed a quite solid and rigorous definition, if you accept their definition, it is clear the money is wasted.
That is the point.
Very interesting, as usual, Andy, congratulations. This is complicated stuff and even the experts disagree on some points. I do not pretend to be right, as I am not an expert, but I do have my point of view and this makes for a great discussion subject.
Not really. Only if it wants to keep the same temperature, but the Earth does not keep its temperature. At present it is about 14.5°C, but 52 Mya it was 23.8°C, and only 20 kya it was 9.5°C. And these are yearly averages. Currently the Earth surface is at 12.1°C in January, and at 15.9°C in July, a 3.8°C difference over the year! They compensate that change for the temperature anomaly graphs or the warming would not be visible. It is clear that the Earth does not emit as much radiation as it receives, at times it emits more and at times it emits less.
There is a very serious problem with averaging radiation over the year, one simplifies the problem running the risk of erring the solution.
Greenhouse gases fulfill two crucial roles to keep the planet full of life. On the lit side of the planet they reject about 30% of the incoming energy. On the dark side of the planet they keep enough heat to prevent deep freezing at all latitudes. Without them the lit side would be >100°C and the dark side would be <-50°C, which is what happens in the Moon, and life would not be possible even to the Fremen of Dune.
I do not think GHGs are saturated. We could obviously have more clouds at night and the planet would be warmer, or more clouds at day and it would be cooler. More CO2 would thicken the troposphere and push the tropopause higher, so the planet would be warmer and with more convection. I don’t think the saturation argument is a good one.
Changing the temperature of the stratosphere would change the climate of the Earth big time. This is what solar variability does, it changes the temperature of the stratosphere by a lot less than 10°C and it affects the climate greatly. What happens in the stratosphere does not stay in the stratosphere.
The CO2-hypothesis of climate change is obviously wrong. It is unable to make succesful predictions other than warming is going to continue. However, the fundamental problem is that its challengers look even less convincing (all but one). You cannot cause centennial or longer warming of the planet by moving heat around the climate system, which is what internal variability does. The ocean is tremendously cold with an average temperature of 3.9°C. Luckily it is very stratified or we would freeze to death. The planet could cool down by stirring the ocean a little bit more, but we are in an ice age, we cannot warm the planet with heat from the ocean. So to have global warming for a period far longer than the multidecadal atmospheric-oceanic oscillations the energy imbalance of the planet MUST be altered. That’s why many scientists accept the CO2-hypothesis despite its serious shortcomings and despite lots of evidence that contradict it. The science corpus does not abandon a hypothesis for no hypothesis. For the same token it does not accept a new hypothesis if it does not understand it no matter the amount of evidence that supports it. It is what happened to Alfred Weggener. His hypothesis was not accepted because scientists could not understand how continents could move (they weight a lot).
Clouds (liquid water) are opaque to IR.
Great perspectives. Have always been interested in your opinions, here and on Climate Etc.
“..the earth does not keep its temperature.” Requires some definition. Usually people are talking about a steady state condition, and over some lengthy period of time. If the earth were out of heat balance for one reason or another, it would be either be net heating up or net cooling down. The temperature fluctuates over time, but is largely stable for the purpose of these discussions. The reason it is not completely constant is due to many factors, but in the long run the earth can be said the be in heat balance with the energy it receives from the sun.
Tom, How long a run? The current Ice Age is either 2.5 million years old or 30 million years old, depending upon whether we measure from the polar ice cap or the Antarctic one. I don’t think the Earth has ever been in thermal equilibrium.
Tom, the Earth is always changing its temperature, from day to day, month to month, year to year, decade to decade, century to century, millenium to millenium, million year to million year. There is no steady state but a constantly changing push (Sun)-mix (ocean/atmosphere)-respond (OLR). Equilibrium, balance, steady state, certain period, are wrong concepts that get people lost. Stability is OK if properly defined, for example as life-compatible.
If the planet can change its surface temperature one year to the next by +0.42°C (Feb 2015 to Feb 2016) it is clear that it is not stable, nor in balance.
The stability of the Earth temperature is due to the constancy of the Sun and the equalizing role of the ocean, not to some supposed radiative balance that does not exist.
Javier.
“Not really. Only if it wants to keep the same temperature, but the Earth does not keep its temperature. Earth is always changing its temperature, from day to day, month to month, year to year, decade to decade, century to century, millenium to millenium, million year to million year.
You seem to have jumped from the contention of energy in equals energy out to discussing temperature instead, which is not what the comment was about.
You were better using this line
“”he stability of the Earth temperature is due to the constancy of the Sun and the equalizing role of the ocean, not to some supposed radiative balance that does not exist.”
which did seem to contradict your previous assertion re temperature even though here you presumably mean energy.
Energy and temperature are not he same thing.
On the one hand you say, “…the Earth is always changing its temperature..”, and on the other you say, “The stability of the Earth temperature is due to the constancy of the Sun and the equalizing role of the ocean, not to some supposed radiative balance that does not exist.”
Here’s some information for you. The earth only receives of and disposes of energy by radiation. There is no conductive or convective transfer of heat to or from outer space. If the earth was not shedding to outer space via radiative heat loss approximately the same amount of energy that it constantly receives from the Sun, then it would be over the long run constantly heating up, or vice versa. It is a dynamic equilibrium, so the temperature at any point in time or space is not constant, but, it is an equilibrium, and the controlling factor is radiative energy transfer.
The temperature of the Earth is stable in the sense that it has varied between 8°C and 28°C during the past 540 Ma. It has not been 3°C or 33°C or we would not be here. That’s what I mean by stable. Changing only by plus/minus 10°C is very stable considering the temperature of other planets.
Equilibrium = a state in which opposing forces or influences are balanced.
Balance = 4 : a state in which things occur in equal or proper amounts
At any point in time the temperature of the Earth is not in equilibrium and the radiative energy “in” is not the same as the radiative energy “out”.
From July to January the Earth cools by 3.8°C. From January to July the Earth warms by 3.8°C. This is despite the Earth receiving a lot more incoming radiation in January than in July, because it is closer to the Sun. But the total outgoing radiation (reflected+longwave) is maximal in November-December.
So both temperature and radiation are changing a lot constantly and often in opposite directions. The Earth sometimes warms despite receiving less radiation, because it emits even less, and then it does the opposite and cools despite receiving more radiation because it emits even more. Describing that as equilibrium or balance is silly.
I think you know a lot less about this than you think you know. Perhaps you should start with this figure from the Wikipedia article on seasons:
Javier
“At any point in time the temperature of the Earth is not in equilibrium and the radiative energy “in” is not the same as the radiative energy “out”.
Please.
No matter how far away the heating source is at any time of the year the energy in equals the energy out.
It is called TOA as it is the theoretical level where energy in equals energy out regardless of how much is coming in.
One does not talk of the temperature as being in equilibrium.
You are in error Angech. At any time of the year, energy in does not equal energy out. Check figure 1 in:
Carlson, Barbara, et al. “Spectral signature of the Biosphere: NISTAR finds it in our solar system from the Lagrangian L‐1 point.” Geophysical Research Letters 46.17-18 (2019): 10679-10686.
The yellow curve is energy arriving at ToA over the course of the year (TSI). The green curve is energy departing ToA (TOR = RSR + OLR).
Javier Reply to angech
You are in error Angech. At any time of the year, energy in does not equal energy out. Check figure 1 in:
Carlson, Barbara, et al.
The yellow curve is energy arriving at TOA over the course of the year (TSI). The green curve is energy departing TOA (TOR = RSR + OLR).
–
Oh dear.
The time to dot the I’s and cross the T’s again.
Javier
“At any point in time the temperature of the Earth is not in equilibrium and the radiative energy “in” is not the same as the radiative energy “out”.
Basic concepts.
We were dealing with the earth’s energy purely from heating from the sun and space, at least I thought we were and are.
But to be clear, Earth is not a non heat producing source so there is more energy going out than what comes in always.
Most discussions focus on the heat questions ignoring this and concentrate on the issues of what happens to the energy coming in.
Let us both focus on the usual scenario.
The heat coming in [just considering the sun] varies as to the distance from the earth plus any albedo changes.
Full stop.
The TOA is where the energy coming in balances the energy going out.
By definition.
Therefore it is not possible to have a radiative imbalance.
Just not possible.
So we have a conundrum.
Carlson, Barbara, et al. want to find an imbalance to warm up the earth.
Which is illegal by definition.
The yellow curve is energy arriving at TOA over the course of the year (TSI).
Wonderful, legal.
Note there is more heat TSI coming in in winter NH when the sun is closest to the earth? Is this correct?
It varies by 22W/M 2 Willis 2014.
Now the magic claim.
The green curve [ Ceres] is energy departing TOA (TOR = RSR + OLR).
Illegal.Why
TOA, by definition is where the outgoing must match the incoming energy.
If it does not then either it is not the TOA or she and her team have made a miscalculation or a wrong assumption.
None of the TOR listed are real, can be reral
ISCCP blue dots straight line [dead giveaway] is a 1982 system current average guesstimate.
annual mean current estimate is a straight red line
Pre industrial dotted straight red line is a made up historic estimate
TOR wavy line is a made up estimate
TOR red wavy line is a made up estimate
Crees green wavy line made up estimate
TOR wavy blue ISCCP made up estimate.
Normalized.
Faked by putting in values
“.For more explicit comparison of the relative seasonal variability, the ISCCP data have been normalized to match the 0.7-W/m2 CERES value for the global annual-mean energy imbalance. Often cited as the smoking gun of global warming, the 1.1-W/m2 GCM value is substantially larger than the CERES 0.7 W/m2.””
GCM has shortcomings “the seasonal variability of TOR, RSR, and OLR in response to solar forcing is sufficient to provide diagnostic information on GCM shortcomings in ocean heat transports and energy sequestration.”
Not able to be assessed but we assessed it anyway,
“Given the inherent difficulties in determining TOR with sufficient accuracy and with adequate sampling of the diurnal cycle, and given also similar difficulties in modeling climate, it would be premature to draw definitive conclusions.”
So we went a million miles out where the spectral values were reduced to a more accurate single data point of information which could be filtered through all our other data sources to tell us where which clouds were on any given day on the earth, a million miles away at thast precise second. Just like an exoplanet 40 light years away.
“”This is where the new perspective that is now available from NISTAR data may help to resolve this issue.”
Jvier, you like to present accurate data.
Could you please give a more reliable comparison if you wish your argument to be taken seriously.
You have probably moved on, but I’ll give it another shot. Your chart has a simple explanation, and it is not relevant to what I said. What I said was that the earth only receives and sheds thermal energy by radiation. Any other sources of thermal energy such as burning fossil fuels or radioactivity are completely insignificant. If the radiant energy did not balance out over the long run, then the would be net heating or cooling, which there is not. It’s not really very complicated. And if there were no GHE, the earth would be much colder and we would not be having this discussion. No one disputes that.
“The science corpus does not abandon a hypothesis for no hypothesis.”
I don’t like the wording on this statement. Science should abandon a hypothesis once it is disproven, not because someone posits a different hypothesis.
CO2 driven climate change is kept on life support by hiding declines, adjusting historical records, and by shutting down opposing viewpoints, not by the strength of its evidence.
The CO2 hypothesis has been disproven by the long pauses in temperature vs increasing CO2. This is a proof that CO2 DOES NOT control temperature. If warming exists it is due to a combination of things and there is no proof that changing CO2 will modify anything.
The scientific consensus is like that person that hates to be single and will stick with his/her ugly girlfriend/boyfriend until someone better comes along. No matter how ugly the CO2-hypothesis, it will not be abandoned until a better hypothesis shows up. We skeptics can point how ugly it is until exhaustion, it won’t matter.
Brilliant, as always Javier!
I should have written that the planet always tries to emit as much radiation as it receives.
Their calculation that the stratosphere will cool by 10 degrees at 800 ppm surprised me, but it is probably correct. What effect will it have on the troposphere? Perhaps you can tell us in a future post. I look forward to that.
someone above made a comment about Planck.
“I should have written that the planet always tries to emit as much radiation as it receives”
No. You were right.
Why change it for Javier?
There is no “tries to emit as much radiation as it receives”
It does not have a brain to try with or a battery to store with.
I will have to push this point until the penny drops for people.
Science absolutely dictates that a body must emit as much radiation as it receives.
The reason for this is obvious.
A non heat producing body is given some extra energy.
It is now in energy imbalance.
Structured as it was, entropically stable, perfect, it needs to return to its normal state by discharging all the energy.
It could not hold on to or store any more energy before or it would already have had it and not needed it.
It emits all it receives to return to its steady state.
A body must emit according to its skin temperature. No connection, directly, at how much radiation it receives.
Exactly. And the efficiency of radiative cooling is determined by GHGs (particularly clouds), and the nature of the surface (land, ocean, ice).
The fact that energy in takes place mainly at the tropical band and energy out is lower than energy in at the tropics and higher at mid and high-latitudes demonstrates that the radiative equilibrium is a myth. There is nothing that can impose such equilibrium and as a result the temperature of the Earth is constantly changing. Compensating mechanisms to change by the coupled ocean-atmosphere are responsible for homeostasis that some people mistake for balance.
Scientists are very keen at assuming simplified conditions, like a radiative equilibrium, that allows them to use simplified mathematics to describe the system. The problem is that at the end the assumption has to be checked and see how it affects that it is incorrect, because otherwise the solution obtained is invalid. Assumptions escape the scientific method.
Per the laws of thermodynamics, a planet must emit as much radiation as it receives.
Not really.
Jupiter emits twice as much radiation energy as it receives:
http://ircamera.as.arizona.edu/Astr2016/lectures/jupiter.htm
Key takeaway line—that I wish had received greater emphasis in the above article—is from the last paragraph:
So, how many tens of $trillions are nations around the globe going to spend on reducing “carbon emissions”?
Hint: cue President Joe Biden’s speech yesterday to the United Nations, with its call for worldwide action on “climate change” (almost universally associated with increasing atmospheric CO2 concentration).
There is the old saying: “Science and politics don’t mix.” It’s exemplified in the above juxtaposition.
“Fig. 9 as well as Tables 2 and 4 show that at current concentrations, the forcings from all greenhouse gases are saturated. The saturations of the abundant greenhouse gases H2O and CO2 are so extreme that the per-molecule forcing is attenuated by four orders of magnitude…””
Err, No.
At present the effective height of emission to space of terrestrial LWIR is ~ 8km or 5ml.
That is, at that height more is directed to space than is directed back to Earth.
So, considering “The marked altitude of 84.8 km, in the middle of the CO2 caused divot in the energy curve”
That leave another 77km/48ml of atmosphere before the effective emission height “saturates”
(see below for Roy Spencer’s comment)
From this thread :
https://wattsupwiththat.com/2020/10/26/study-suggests-no-more-co2-warming/?utm_source=dlvr.it&utm_medium=facebook
in which Nick Stokes (chiefly), critiqued this paper …
““We could emit as much CO2 as we like; with no effect.”
The paper says nothing like that. It goes through the old argument between Arrhenius and Angstrom; the Arrhenius argument prevailed, and this paper does not contradict it. The key outcome is probably Table 5, where they compare their CO2 sensitivities with those calculated 50 or so years ago by Manabe, and by Hunt and by Kluft (recent). The fixed relative humidity numbers are 2.9(2.2), 2.2, 2.7, 2.3. The last number is theirs, and is completely in line with the earlier results, and certainly does not say that CO2 could be added with no effect. It says the CS would be 2.3C per doubling.
The forcing increments due to GHG increase are shown in Table 3. They explicitly say, correctly,
“The forcing increments in Table 3 are comparable to those calculated by others.””
“The “saturation” is what it is. The GHE still works. And, I repeat, their calculated CS is 2.3C/doubling. Right in the IPCC range. They have basically repeated the old calculation of Manabe with updated radiative properties, and got a very similar result.”
Nick on why it wasn’t published in a peer-review journal …..
““In science opposing visions SHOULD be published.”
It isn’t an opposing vision. It is a rehash of an old calculation yielding a very similar result. It is always going to be hard to publish that in a research journal.”
““We could emit as much CO2 as we like; with no effect.”
The paper says nothing like that. It goes through the old argument between Arrhenius and Angstrom; the Arrhenius argument prevailed, and this paper does not contradict it. The key outcome is probably Table 5, where they compare their CO2 sensitivities with those calculated 50 or so years ago by Manabe, and by Hunt and by Kluft (recent). The fixed relative humidity numbers are 2.9(2.2), 2.2, 2.7, 2.3. The last number is theirs, and is completely in line with the earlier results, and certainly does not say that CO2 could be added with no effect. It says the CS would be 2.3C per doubling.
The forcing increments due to GHG increase are shown in Table 3. They explicitly say, correctly,
“The forcing increments in Table 3 are comparable to those calculated by others.””
And possibly most damning from denizens’ perspective comes from this thread:
https://wattsupwiththat.com/2020/11/29/slight-beneficial-warming-from-more-carbon-dioxide/
From Roy Spencer:
“I’m afraid I have to agree with Nick on this. The authors used detailed line by line calculations and get the same radiative forcing from 2XCO2 others have gotten. How much warming occurs largely depends upon feedbacks, which were not the main subject of the paper. Talk of near-saturation is nothing new, this is known and included in climate models. There is no such thing as total saturation of the GHE. Ask Venus (with over 200,000x our CO2).
The science:
“So, if a skeptical friend hits you with the “saturation argument” against global warming, here’s all you need to say: (a) You’d still get an increase in greenhouse warming even if the atmosphere were saturated, because it’s the absorption in the thin upper atmosphere (which is unsaturated) that counts (b) It’s not even true that the atmosphere is actually saturated with respect to absorption by CO2, (c) Water vapor doesn’t overwhelm the effects of CO2 because there’s little water vapor in the high, cold regions from which infrared escapes, and at the low pressures there water vapor absorption is like a leaky sieve, which would let a lot more radiation through were it not for CO2, and (d) These issues were satisfactorily addressed by physicists 50 years ago, and the necessary physics is included in all climate models.”
Anthony Banton,
It took me a while to realize that you were quoting the paper and not my post.
Err, yes. The calculations are correct and the attenuation is four orders of magnitude. You deftly change the subject. W&H are not discussing the average emission height, which is as useless a number as the global average surface temperature. They are talking about H2O and CO2 additional forcing per molecule, which is frequency dependent. Their numbers are correct in the clear sky case.
But, in any case I have no serious problem with what Nick or Roy wrote. I do not think the GHE causes all of the surface warming on Venus, there are other factors at work there. But, 96% CO2 and no water are certainly big factors. We need to remember that Earth’s surface (bottom of the ocean to TOA) contains 5 times as much thermal energy as Venus’ atmosphere. Yet, Earth’s surface temperature is 15C and Venus’ is 464C. The lack of water on Venus, due to it’s strong electrical field, is another big problem. Venus’ total atmospheric heat capacity is appalling low.
See here: Can Earth be compared to Venus? | Andy May Petrophysicist
I liked W&H because it brings us back to Earth, it elegantly describes the GHE and how the climate models work. I’ve read the older papers you refer to, they are not nearly as good as this one.
The basic W&H clear sky radiation calculations do show us there is no problem with additional CO2, even if we assume water vapor goes up with temperature. That H2O will necessarily go up is an assumption with no evidence at this time. The billion dollar GCM’s are no more accurate than the W&H model.
What we are left to consider is what clouds will do if the surface temperature warms about two degrees. And, as acknowledged in AR6, no one knows. The argument is not about the radiative effect of CO2, it is about clouds, feedbacks, and convection.
I hope this paper is the end of the CO2 radiative effect discussion. It doesn’t matter. It doesn’t disappear, it just doesn’t matter. The feedbacks, if they are significantly positive might matter, but nobody even knows if they are net positive, much less what their value is. Certainly, two degrees of warming from today, at 800 ppm, is nothing to worry about. Primates evolved and dispersed widely when global temperatures were 10 degrees warmer than today during the Paleocene-Eocene Thermal Maximum. It is unclear to me that sufficient economic fossil fuels exist to get us to 800 ppm in any case.
Andy May, just so! Excellent response.
It is not the lowest altitude at which, across LWIR spectral bands, Earth’s atmosphere radiates to space and how that varies as a function of concentration of GHGs, but rather the highest altitude at which GHGs have effectively reached the asymptotic “limit” (i.e., become “saturated”) in absorbing the LWIR radiation off Earth’s surface and then having thermalized that associated, available energy with N2 and O2 as a result of extremely rapid (on the order of nanoseconds) collisional energy exchanges.
The science supports that the thermalization of GHG-intercepted LWIR off Earth’s surface is essentially complete within the first 10 km of altitude, with realization that there is a portion of the LWIR spectrum (the “atmospheric window” noted in Figure 1 of your article) where combined GHG’s just do not absorb radiated energy.
Per K-T diagram accounting/balancing of power fluxes under assumed equilibrium conditions, 40 W/m^2 escapes through the “atmospheric window” whereas 199 W/m^2 comes off the atmosphere, including N2 and O2 thermal radiations . . . the “atmospheric window” accounts for only about 17% of Earth’s total radiation.
Sorry, should have said the top quote was from Harper’s paper.
I have no quarrel with the numbers. I posted comments from Nick and Spencer to cover that – and you agree.
Turns out the paper is of little concern to the consensus science.
My concern was with the obviously incorrect statement in the paper that “the forcings from all greenhouse gases are saturated”
They are not, as they as climate scientists should know.
And as such should discredit any pretensions of unbiased (or at least knowledgeable) scientific enquiry.
Anthony Banton
“Sorry, should have said the top quote was from Harper’s paper.”
Yes.
You said
“My concern was with the obviously incorrect statement in the paper that “the forcings from all greenhouse gases are saturated
They are not, as they as climate scientists should know.”
Surely that comment depends on context, and as you are making up an argument for arguments sake. you need to provide the context.
Ie you needed to quote exactly what conditions were specified in that article for them to make what seems like a perfectly adequate scientific statement under certain conditions.
You know, like “In this paper considering all fully saturated GHG there is no room for more forcing”‘
Since you did not present any context and are not discussing this post specifically you therefore appear to be making a bogus statement about some personal beef or misunderstanding?
As you said “A blog comment is not scientific backing.”
Anthony,
I agree with angech and will not repeat what he wrote, but I have two additional points that are important, IMHO.
W&H provide us with a rigorous definition of the radiative clear-sky GHE. They do this very well and this is a great contribution and sorely needed. Unfortunately the IPCC has not provided one and uses the term in many different ways. They do this in an attempt to persuade, rather than educate.
One observes they do not define the term, because when properly defined, anyone can see it is not threatening.
Both Wijngaarden and Happer are physicists uniquely qualified for this work. Happer has studied atmospheric physics since the early 1980s and was a co-author of one of the very early investigations into the effect of CO2 on climate.
The term “climate scientist” today usually refers to climate modelers. These modelers have yet to devise a successful climate model, even after spending billions of dollars and millions of man-hours in the attempt. Saying a proper scientist is not a climate scientist is a compliment, IMHO.
Thank you!
“According to the second law of thermodynamics, a thermally isolated atmosphere will reach a constant temperature throughout its height if entropy remains constant. However, gravity bunches up the molecules of air near the surface and reduces their entropy, raising the temperature. ”
Finally, scientific backing for the idea that air pressure has something to do with a planet’s surface temperature (compare Venus, Earth, and Mars, say), and not just GHEs.
A blog comment is not scientific backing.
High pressure of itself does not create persistent warming. Note the word “persistent”.
When you pump up your bike tyres they get warm – you can feel the heat at the end of the pump (Charles’ law).
But the pump and the tyre cools and so does an atmosphere after any compression takes place (eg mass subsidence in a HP cell).
Anthony, Lets distinguish between case 1: the total GHE, and case 2: the enhanced GHE, that is adding CO2.
Case 1: No atmosphere like the Moon versus an atmosphere like Earth’s. Or if you prefer, a transparent atmosphere, versus one with GHGs.
I’m not sure what the temperature of the transparent atmosphere would be, but suspect it would be a uniform temperature from some high altitude to the bottom and that the temperature would be larger than the blackbody temperature and most of that temperature increase would be due to pressure according to the PVT law. We would assume that the atmosphere does not circulate, even though I’m not sure what gas that would be. It would also have to a perfectly transparent gas.
Case 2: enhanced GHE, adding CO2. Gravity doesn’t change, but CO2 is much denser than dry air and H2O is much less dense. How these volumes change and how fast, could make a difference in surface temperature, how much is uncertain. But, we are talking about very small temperature changes. probably only 0.13 degrees per decade according to Dr. Spencer. Some portion of that 0.13 change might be due to air pressure changing.
I don’t follow your statement that “most of that temperature increase would be due to pressure according to the PVT law.” Now, if solar heating makes the surface temperature non-uniform, the (by hypothesis, perfectly transparent) atmosphere’s heat capacity would slightly reduce the non-uniformity and thereby make the average surface temperature slightly higher than it would be if the surface temperature had more variance.
Absent that (presumably negligible) effect, though, I don’t see how an isothermal atmosphere, no matter how heavy, would affect the equilibrium surface temperature. Say the surface temperature is somehow irradiated so isotropically as to assume a uniform temperature. That uniform temperature must at equilibrium be such that the surface radiates out as much as it absorbs.
This follows from the fact that a perfectly transparent atmosphere can gain or lose heat only by conduction with the surface, and at equilibrium the net conduction is zero by definition. This is true independently of the atmospheric pressure.
In short, it seems to me that Mr. Banton has the better of the argument. What am I missing?
Only a static atmosphere can become isothermal. A gaseous atmosphere can never be static due to temperature and density variations in the horizontal plane. As soon as convection starts the GHE develops.
No convection, no GHE.
Or is it no GHE, no convection?
Stephen Wilde stated:
Oh, no. Stop the presses! You must immediately inform all weathermen and airplane pilots that there can never be such a thing as stable temperature inversion layer in Earth’s atmosphere.
They will be simply amazed to hear of this update.
Joe Born
Reply to Andy May
“I don’t [want to] follow your statement that “most of that temperature increase would be due to pressure according to the PVT law.”
” Now, [If I change what Andy May said to some other situation] if solar heating makes the surface temperature non-uniform”
Let’s just stick to the argument as formulated, Joe, tangents are not helpful.
“I don’t see how an isothermal atmosphere, no matter how heavy, would affect the equilibrium surface temperature.”
Perhaps this might help.
Only a guess.
With an extremely dense but transparent atmosphere Gravity has made the air molecules at the bottom closer together and more capable of interacting.
Radiation returns to space in two ways. By IR from the surface and by conduction at the air surface interface.
The heated molecules rise and induce a lot of convection in the dense lower atmosphere.
Convection helps spread the possible radiating area further out
This reduces the intense heat going out from under the sun and leads to a far larger surface area warming up to radiated the convected heat.The now warmer colder large areas are at a higher temperature than they were and the average surface temperature rises as the hot surface are dips a lot more than the cold ares go up.
Part of the reason for Venus being warm all over according to some ?
You called my first paragraph’s assumption of a non-uniform surface temperature a tangent, but you assumed exactly the same thing (“the intense heat going out from under the sun“, “The now warmer colder large areas“).
The effect you then describe is exactly what my first paragraph referred to, i.e., the atmosphere’s reducing the surface temperature’s non-uniformity and thereby increasing the average temperature required (because of the fourth-power relationship) to achieve the same average radiation.
As you correctly observed, though, that’s not what Mr. May assumed in his Case 1: for that case he assumed “uniform temperature” in the atmosphere and that “the atmosphere does not circulate,” so he’s ruling out the effect that you describe (and, again, that I referred to in my first paragraph).
That’s why I prefaced my second paragraph with “Absent that (presumably negligible) effect. . . .”
To me it appears that Mr. May is basing his discussion on bad physics. It’s hard to tell, though, because he didn’t write clearly for us to be sure. I’m not criticizing his writing, because we all leave latent ambiguities. But to me it’s a red flag that he doesn’t seem inclined to clarify.
Joe Born to Andy May
“I don’t follow your statement that “most of that temperature increase would be due to pressure according to the PVT law.”
It is quite simple and someone of your repute is being disingenuous to an extreme when you say you do not understand or admit that there is a relationship between pressure and temperature.
Anthony Banton himself wrongly commented
“High pressure of itself does not create persistent warming.”
Objects come together when their vectors intersect.
Gravity comes into play to cause passing objects to come together.
Gravity the results in a pressure effect as the size of the joining objects grows.
Ultimately high pressure causes suns to form and produce persistent heat.
Atmospheres with a gravity distribution of molecules at different densities results in heat generation.
Gas giants do not need a sun to produce heat.
On earth we need the sun but that does not prelude a relationship,embedded in physics, between pressure and temperature.
Ruling out the role of Co2 as having an important relationship is wrong as well because these relationships are all important facets of science.
Thank you for your considered, and polite reply to me. perhaps you could treat Mr May’s views with courtesy also?
No one denied PV=NRT. No one denied that the higher surface temperature of Venus results at least partially from its heavier atmosphere.
But Mr. May made a statement in which he appeared to indicate that at equilibrium a planet that has a perfectly transparent high-pressure atmosphere would have a higher surface temperature than an otherwise-identical planet whose atmospheric pressure is lower. Nothing about PV=NRT requires such a result, so I see nothing discourteous in extending Mr. May an opportunity to clarify his statement.
To Andy May above at 4.43 am Thanks for the answer to my request for the location of the NYT paper.Very kind of you.
Ed.Nalton.
Sorry, you need to determine why your tire cools. It is not because the pressure stabilizes and has no further change. Think conduction to the air and heat loss.
Compression and decompression is a continuous process in an atmosphere so the system doesn’t cool in the way a tyre does when pumping stops.
The issue is that pressure does cause a permanent increase in temperature unless there is another variable change. PV = nRT!
Yes it does.
It does not. It does not have a solid impermeable barrier.
Andy,
I know that CO2 is referred to as a well-mixed gas. However, a movie made by NASA with OCO-2 data shows minor variation in concentration spatially, and more vertically.
Therefore, I’m surprised that Fig. 2 (RH side) shows CO2 concentration as constant. Even more surprising is that only the ‘magic molecule’, CO2, is constant with altitude. This seems unlikely to me. How do W&H justify their assumption(?) that only CO2 is constant with altitude?
Good question, I do not know. I will ask.
Clyde, The atmospheric concentrations came from their reference 18, Clough, 1986. You can download it here:
(PDF) AFGL Atmospheric Constituent Profiles (0.120km) (researchgate.net)
I see that the paper, describing the Standard Atmosphere, for doing atmospheric corrections of satellite imagery, was published decades before OCO-2 was launched. I imagine that better data are now available.
I don’t know. That is the only reference I’m aware of.
I checked vW and Happer. It is theory. Unfortunately my finding is that the practical results do not support the theory.
See here
https://breadonthewater.co.za/2021/01/26/am-i-a-climate-denier-denialist/
If you ask me what is wrong? I don’t know. I think there is no Planck curve for earth? If I board a plane and keep watching the T at 10km it stays at -50C with very little variation….there is no curve….it is discrete.
Note this post, especially the presentation of the warming at the end of the post. My own results show same even more dramatic. I measured ca. 0.05K/ year warming in the arctic which gradually goes down per latitude in the NH to almost no warming in the SH and even cooling in the antarctic areas.
https://breadonthewater.co.za/2021/04/05/unexpected-ice/
Sorry if I did not make this clear. If the ghg theory of vW and Happer were correct, which plays out in the atmosphere , we should see a rate of warming that is more or less the same whereever I measure on earth.
Henry,
The W&H model is just that, a model. It explains the radiation effect of the common GHGs, it does not include convection or clouds. It is just a very detailed and precise definition of the radiative GHE.
They do not claim their model reflects reality. It just shows the CO2 effect is very small.
Andy,
In the end they made claims on the contribution to deltaT by delta[CO2} en delta [CH4], 0.01C/annum and 0.001C/annum respectively, if I remember correctly.
However, in the discussion here:
https://www.scirp.org/journal/paperinformation.aspx?paperid=99608
the question is raised whether CO2 indeed does contribute anything to the increase in temperature.
The theory is wrong.
I am going with Aleksandr
From the post:”Since the energy emitted to space is less, Earth’s surface must warm.”
I am not sure how this is possible. You have a fixed frequency range and E = h*f with h being a constant adding more molecules will emit more energy not less.
mkelley,
The surface will warm, but the stratosphere will cool dramatically. The reason? The CO2 and water vapor in the troposphere block emissions in their respective frequencies. The thermal energy (heat) from the surface is carried to higher altitudes by evaporated water and natural convection. At the higher altitudes and latitudes, the water vapor is gone, and the additional CO2 emits radiation to space cooling the stratosphere. They calculated the stratospheric cooling will be 10 degrees.
Depends where you are.
“If we assume Earth is a blackbody, then subtract the solar energy reflected, from the hypothetically non-existent clouds, atmosphere, land, ice, and oceans; we can calculate a surface temperature of 254K or -19°C. The actual average temperature today is about 288.7K or roughly 15.5°C. This modeled difference of 35°C is often called the overall greenhouse effect”.
The temperature of the Earth’s surface is constantly changing over time and in different places. The concept of the average global temperature of the Earth (AGT) has no physical meaning, as well as the arithmetic mean of the measured temperatures used as a measure of the AGT. This value (15 оС) is also incorrect from the point of view of statistics due to the uneven distribution of meteorological stations. Even the IPCC admits that 15 °C is the average temperature of the Earth “excluding Antarctica” (2nd Report, Technical Summary, 1995). In fact, Greenland and many other uninhabited places should also be excluded.
Of course, using the Stefan-Boltzmann equation to determine the temperature of the Earth’s surface is incorrect. The problem is not only that the Earth is not a completely black body, but also that the 240 W/m2 value used to calculate the temperature using this equation is unreliable. Obviously, each mini-area of the surface differs to a different degree from an absolutely black body, and also absorbs and reflects a different amount of energy. Averaging of energy in this case is also not reliable and unjustified, like averaging temperatures.
Comparison of the two dummies is in itself a fiction, not to mention that there is no physical evidence that the difference between them is due to the so-called “greenhouse effect”.
Agree completely. Have you been reading my notes? 😁
I agree with you. Good points and well said.
I just hope will get a little warming out of improving CO2 levels. The next LIA is due and will be worse than the last since the Holocene is definitely cooling and is itself due to end and the next glacial period begin. https://www.reddit.com/r/climateskeptics/comments/e9gwxa/prof_numlocks_ultimate_climate_lecture/
Several years ago, I did calculations similar to W&H’s with results that were very similar though not as detailed. In the course of doing the calculations it occurred to me that I’ve never seen a calculation of the Earth’s atmospheric temperature if it only contained nitrogen, oxygen, and argon, which make up 99.96% of the air and are all infrared inert. I have read that a climate model was run without any CO2 and had a final state atmospheric temperature of 0 K, a tiny bit implausible.
If you measure the temperature in a tank of nitrogen gas it will be the same as room temperature and will track room temperature as the room heats and cools. The heat is transferred to the gas via conduction and convection. Just because there is no transfer of energy by radiation does not mean that the gas temperature will go to zero. The Earth’s atmosphere should behave similarly.
Sunlight heats the Earth’s surface. This heats the air by conduction which then convects aways from the surface. The air cools adiabatically as it rises. This occurs all over the daylight side of the Earth with the hottest spot directly underneath the Sun. The rising air will mix and create convection currents in the atmosphere. The surface will radiate to outer space.
On the night side, there is no incident solar radiation but the surface still radiates its heat outward to space and contact between the surface and air will still transfer heat between the two.
Two processes control the exchange of heat between the atmosphere and the surface on both the daylight and night side of the Earth.
A downward air convection current will heat the surface by conduction if the air is warmer than the surface. This will also increase the rate of surface radiation. Since the surface absorbs heat from the air, it will also cool the air suppressing convection at the surface.
If the downward air current is cooler than the surface, i.e., the surface is warmer than the air, the surface will cool off while warming the air. The radiation will decrease since the surface has cooled but convection will be increased since the air has warmed.
To summarize, heat enters the Earth via Sunlight, the surface radiates heat to outer space, and the air acts as a store of heat that it exchanges with the surface via the two processes above.
After a long time the atmosphere will come to thermodynamic equilibrium, a state of constant uniform temperature at all altitudes. That temperature can’t be zero Kelvin. Sunlight heating any part of the surface would initiate convection air currents via the two processes discussed above, resulting in the atmosphere no longer in equilibrium.
I think that surface/atmosphere temperature would be a uniform 389 K = 116 C, the radiative temperature due to the 1300 W/m^2 of incident solar flux. It can’t be hotter by the second law of thermodynamics. The rotation of the earth makes sure the there is no longitudinal variation in temperature. If the poles were colder than the low latitudes, the second law again would ensure that heat would flow to the poles. The net effect is that at equilibrium the atmosphere is isothermal at 389 K.
This means that there is no need for CO2 to heat the atmosphere, it’s naturally hot. I think that what actually happens is that sunlight heats the oceans, the water evaporates and rises to the top of the atmosphere where it condenses and radiates its energy away, cooling the air and giving us a livable . At best, carbon dioxide acts as a weak coolant at the top of the atmosphere.
I’ve always been highly sceptical that removing trace CO2 from the atmosphere would have any significant climatic effect – if we assume that plants and most (nonmicrobial) life would miraculously not go extinct. (To hypothetically remove the confounding variable of biosphere extinction).
CO2 cools all air above the tropopause. During cold outbreaks in winter there are often stratospheric incursions. So CO2 cooling of the stratosphere can bring a cooling effect down to the troposphere and the earth’s surface.
The statement “Per the laws of thermodynamics, a planet must emit as much radiation as it receives” is an approximation since our planet converts a significant portion of incoming radiation into potential energy in the form of chemical bonds via photosynthesis. Even if this is only one percent of the incoming energy, this is significantly more than the estimates of the difference between incoming and outgoing radiation. Hence the supposed imbalance may be completely explained by a more comprehensive energy balance.
What about cause and effect?
The Greenhouse Effect is impossible without at lapse rate. If the lapse rate is zero then the effective radiation height is zero (the surface).
But the lapse rate is caused by convection, not greenhouse gas. Thus the Greenhouse effect is a result of the lapse rate and thus a result of convection.
I was hoping Andy would also take a look at Coe et al 2021 and compare their results with W&H. Both use HITRAN and ignore clouds but give significantly different results. I haven’t seen any refutation yet of the Coe paper.
The Coe paper shows a sensitivity of 0.46 C without feedbacks and 0.5 C with water vapor feedback. It would be nice to know how two skeptical papers could produce such different results.
E=mc’2 and c=pi r’2 seem to be unknown to climate scientists.
Yet they helped get man to the moon and back , now heading to Mars.
NASA and others seem to be off track with their priorities .
Too many variables in climate for any ‘scientist or body’ to claim its settled .
The insulating effects of our atmosphere is entirely due to a convective rather than a radiative greenhouse effect. The only thing that a change in CO2 could do to change the surface temperature of the Earth would be to change the surface pressure. That change is negligible for a doubling of CO2 so hence the climate sensitivity of CO2 must be negligible..
Yes, no convection means no GHE.
Refer back to the various posts here by me and Philip Mulholland.
They describe how the GHE arises.
“A perfectly transparent atmosphere would radiate all surface emitted energy according to the blue line in Figure 1.”
So the GHE-Earth radiates less than the blackbody Earth. A body that radiates less is cooler than a body that radiates more, because T^4. This means that the greenhouse effect cools the Earth.
The GH effect began billions of years ago when IR absorbing gases first appeared in the atmosphere. We know that life began almost 4 billion years ago so the warming of our planet from 255k to 288k must have taken place before then. I’m just making two simple points, the GHE didn’t start yesterday and it has already caused a lot of warming.
We also know that the relationship between the absorbance of IR by greenhouse gases and the gas concentration in the atmosphere is approximately logarithmic. The greatest increase in absorbance/warming was due to the first increase in greenhouse gas. Successive additions of gas had smaller effects. We are now approaching the other end of the curve where the increases in gas concentration have only very small effects on absorbance and warming.
The effect will never reach zero but it is sufficiently small that there is no justification for alarmism or counteractive measures. This applies to all greenhouse gases mixed in the atmosphere, regardless of their greenhouse characteristics when measured individually.
“3 W/m2, the area between the black curve and the red curve [in Fig.1]”
The black curve – where it exists – seems identical to the red curve. What did you want to prove?
Just that. The green curve to the black curve is the CO2 caused forcing from 0 ppm to 400 ppm. The tiny difference between the black a red curves is the forcing from 400 ppm to 800 ppm. Next to nothing.
What a tragedy to see that the whole world is going into self destruction mode because of a completely wrong theory or ‘model’.
Good remarks by Aleksandr and Paul but Paul has the 99.96 slightly off. I think water is on average 0.4 or 0.5% and CO2 is 0.04%
More carbon is OK!
ANdy May; I admit I only read as far as your figure 1 but the annotations on that figure are so clearly impossible that it calls your entire essay into question.
The atmosphere does mechanical work, wind is mechanical work, raising water to high altitudes is mechanical work and so on. The energy from this clearly comes from absorbed solar energy. That makes the atmosphere the working fluid of a classical heat engine as described by Carnot in about 1810. Two things stand out about heat engines. Firstly 100% efficiency is impossible, there must be a hot junction where heat is injected into the working fluid and a cold junction where heat is abstracted from the working fluid. The working fluid cycles between the hot junction and the cold junction. The second things is that the cold junction must be at a point where the pressure is significantly lower than that at the hot junction.
These conditions are of course met in our atmosphere since the hot junction is the surface and especially the surface near the equator. The cold junction is the top of the convective loop – the tropopause. Heat is abstracted from the atmosphere at this altitude by GHG’s radiating to space. Interestingly, if there were non GHG in our atmosphere there could not be a cold junction and without that no convection. No convection means no lapse rate, isothermal and saturated atmospheric column, no clouds, no wind, no net evaporation, insolation average around 340 watts/sqM and a average surface temperature (whatever that means) of around 270K – about the same as the moon. More significantly the surface temperature is determined by the insolation level and the thermal time constant of the surface. Consider how fast beach sand or a concrete footpath or even dry grass and soil heats up in summer (less than 1 hour) and it is obvious the surface time constant is very short. Peak insolation at the equator is around 1340 watts/sqM at noon corresponding to a surface temperature on land of around 113C. At latitude 37 its still around 70+C. Of course at night its far far below freezing. We can see that by looking at the temperatures reached inside a closed car in summer.
But to return to your figure 1, your annotations show no radiation to space from that altitude which means no cold junction so how could convection stop at that point. A rising air column continues to rise because its internal energy is higher than that of the surrounding air (that is a combination of its temperature pressure water vapour content etc). It stops rising when its internal energy ceases to be higher than the surrounding air but for that to happen the rising air has to lose energy. In our atmosphere the top of the convective loop is at the tropopause, indeed it defines the tropopause. The tropopause is the coldest point in the atmosphere so how could the rising air at the tropopause lose energy other than by radiation to somewhere even colder ie: radiation to space? If the cold junction was set by CO2 according to your diagram convection would rise to 84 km, if set by water vapour it would only rise to 2.8 km. The tropopause however is at around 12 km average (18km in the tropics)
I think you will find the apparent 2.8 km radiation altitude for water vapour comes about because there are huge number of very closely spaced lines. Radiation from between the lines comes from the surface, cloud tops etc, radiation at the lines comes from the tropopause. The lines are simply too close together to be resolved by the satellite spectrometers. Radiation from CO2 shows an emission temperature of around 220K which is the temperature of the tropopause.
Absent any GHG including water, there would still be convection. You should notice that the lapse rate depends on gravity (pressure) not GHG gases. They don’t enter into the lapse rate calculation.
Non-GHG gases can still be heated by conduction with the earth’s surface. Therefore there is still a “hot” plate for the engine. The lapse rate insures that there is a “cold” surface at lower pressure .
Lastly, because of the oceans, there will always be water vapor rising and cooling. Water is the predominate GHG and I doubt that the removal of non-condensing GHG gases will affect much.
No Jim; You are correct to say the lapse rate does not depend on GHG’s. It comes about because as the air rises it expands and adiabatic cooling occurs but I didn’t say the lapse rate occurs because of green house gases. I said it comes about because of convection and is maintained by convection.
Your point about a cold junction being created by lapse rate is not correct. To consider the cold junction in terms of temperature is a very dangerous way of looking at things, yes the temperature falls as the air rises but conversely the temperature will rise as the air falls again. BY the time it got back to the surface it would be back to the same temperature at which it starts so what would drive convection. This is an adiabatic process which means “without energy transfer” ie: the internal energy of the air does not change. But for a heat engine to function energy must be lost from the working fluid at the cold junction and it is this loss of energy which allows the air to be recompressed back to the surface using less energy than was released in the expansion. The air at the tropopause can ONLY lose energy by radiation to space since it is already colder than the air above and below. But any gas that can radiate energy in the thermal infrared (which, given the temperatures involved, is the only band where significant radiation can occur – Planks law) is BY DEFINITION a green house gas. No GHG’s no energy loss. Without that energy loss convection stops, the atmosphere over time will become isothermal due to conduction and will also become saturated wrt to water vapour simply because for water to condense means it has to lose energy and without GHG’s it cannot lose energy. If the atmosphere is saturated net evaporation stops. I admit there are secondary processes, heavy dew at night when the surface gets very cold and some surface evaporation as it warms up again but these are very local surface effects which would not give rise to weather as we know it.
Michael,
Completely incorrect. You forget that frequency matters. If a molecule at the tropopause emits radiation at a frequency absorbed by a molecule in the stratosphere, say CO2 or O3, that molecule can become excited and warm the surrounding air. This process goes on until the radiation can finally be emitted to space.
At some frequencies, like 700 cm^-1, the final emission to space does not occur until 84 km, in the mesosphere.
Emission height is frequency dependent, a point often ignored.
In Figure 1, you can see the reversal of the black and red lines at the bottom of the CO2 divot, this means the final emissions at 800 ppm are cooler than the 400 ppm emissions. The extra CO2 is cooling the mesosphere, and probably the upper stratosphere.
Andy; you state “Completely incorrect. You forget that frequency matters. If a molecule at the tropopause emits radiation at a frequency absorbed by a molecule in the stratosphere, say CO2 or O3, that molecule can become excited and warm the surrounding air. This process goes on until the radiation can finally be emitted to space.”
This is a very interesting comment because what you are essentially claiming is that the colder tropopause radiates NET energy to the warmer stratosphere which then radiates it away to space. Sure colder objects can and do radiate to warmer objects but then the warmer objects also radiate back towards the colder ones at the same wavelengths and because they are warmer the radiation is higher so net energy flow is ALWAYS from warmer to colder. Its the second law of thermodynamics.
The reason that the final emissions at the line edges are cooler at 800 ppm cf 400 ppm is because as concentration rises the line broadens. Emission/absorption lines are lorenzians which are extremely close to gaussian profiles. If you double the concentration it is equivalent convolving the gaussian profile with itself. The result is also a gaussian but with a wider spread (larger standard deviation). As a result the total absorptivity of the gas column at the edges of the line increases so the last 1 abs comes from closer to the top of the gas column ie: higher in the atmosphere where it is a little colder.
Michael, I’m sorry you comment makes no sense. Your comment:
Is completely incorrect. Refer to Figure 2 in the post.
Your rambling comment is nonsense. Read the post, in full, I’ve tried to make it clearer and more understandable. W&H have defined the GHE in a very robust and precise way, something the IPCC should have done decades a go, but didn’t because if you understand the radiative GHE you realize we have nothing to worry about.
Andy; There are so many points in your article that I find utterly incompatible with what I know of spectroscopy that its difficult to know where to start. For example you say
“A blackbody is usually defined as a perfectly black cavity kept at a constant temperature. All energy that enters the cavity is absorbed by the cavity walls, and they emit exactly the same amount of energy, but the wavelength of the emitted radiation is not the same as the energy captured.”
Nope, that not the definition of a black body I am familiar with. A blackbody is simply an object with an absorptivity (or emissivity) of 1 at the wavelength of interest. Nothing whatever to do with a cavity or temperature and no not all the energy is necessarily absorbed, it depends on the wavelength. Also the amount of energy emitted is not necessarily the same as the amount absorbed. If the body is warming up the energy emitted is less and vice versa if it is cooling down. You are correct that wavelength matters and it is quite possible for an object to be a black body with respect to 1 wavelength yet have a low absorptivity at other wavelengths. For example, glass has very high absorptivity in the IR yet very low absorptivity in the visible which is why it can be used as a heat filter. That means glass is a black body (or very close to it) in the IR but not in the visible.
You also say
“According to the second law of thermodynamics, a thermally isolated atmosphere will reach a constant temperature throughout its height if entropy remains constant. ”
I dont see what entropy has to do with it, infact if the atmosphere is thermally isolated but with different temperatures with altitude then as the temperature equilibrates through the column the entropy will increase. Entropy is defined as
“a thermodynamic quantity representing the unavailability of a system’s thermal energy for conversion into mechanical work”.
Initially the temperature difference between the top and bottom of the atmosphere could be harnessed to do work, but once equilibrated that difference no longer exists so no work can be extracted ie: entropy has increased as the temperature equilibrates. If the atmosphere is thermally isolated ie: no heat in or out then sure conduction will eventually ensure it becomes isothermal.
I could go on but these posts become too long for people to read.
It would appear you do not understand my points regarding heat engines. The topic is too large to go into in detail in this context but you can look it up readily on the web.
Dear all,
I can´t believe that the CO2 radiation comes from the mesosphere in 84km. Also the CO2 concentration is the same as at 0km, the density of the atmosphere at 84km is much too low to emit this amount of radiation. Normally I would suggest CO2 radiation from a 100mbar level at about 8-12km at the end of the troposphere. This would also explain the small increase at its main absorption band (15µm) coming from a hotter stratosphere. Perhaps I am wrong. Could please someone check this?
Dear Eike; you are absolutely correct. If you look up Heinz Hug you will see he measured the absorption profile of CO2 at the pressure and concentration prevailing at sea level. There are 3 bands, the P band, Q band and R band. P and R are quite broad, the central Q band is stronger but much narrower. The absorbance of the P and R bands is around 0.125 abs/meter whereas the Q band is around 0.3 abs/meter. For our entire atmosphere this translates to around 1000 abs for the P and R branches and about 2400 abs at the Q band. These figures were for 357 ppm at 410 ppm they would be 1150 abs and 2760 abs respectively. 90% of the emission to space comes from the last 1 abs of the CO2 column, 99% from the last 2 abs. That says the last 1/1150 of the CO2 is at an altitude of around 8-12 km and the last 1/2760 of the CO2 column is slightly higher where the temperature is warmer. Since the air column extends far higher ( your figure of 100 mbar implies 1/10 of the air column is above the tropopause) it implies CO2 is pooled in the lower stratosphere. This should not be too surprising given the stratosphere is static – little mixing – and CO2 at molecular weight 44 is considerably denser than air molecular weight 29. Indeed I remember an experiment in primary school (many decades ago) where we filled a beaker with CO2 (vinegar and sodium bicarbonate) and were able to pour it from beaker to beaker as shown by a candle in the 2nd beaker which went out as we poured. Could do it a few times before it mixed with the surrounding air.
Congratulations in your very acute observation of the central spike in the emission over the CO2 band. There have been many cases where very significant conclusions follow from what seem like tiny artifacts and this one is indeed significant.
Michael, your arguments make no sense and are irrelevant to her question.
Andy; you showed in a reply to Eike a plot of the absorption spectrum of CO2 . The left hump is the P branch, the middle spike is the Q branch and the right hump is the R branch. Your plot was taken at extremely low pressure which is why it shows hyperfine structure, if you look up Heinz Hug you will see what it looks like at 1 atm 357 ppm CO2.
Are you familiar with the concept of absorbance. it is defined as
absorbance = -log(Iout/Iin)
I absorbance absorbs 90% of the incident radiation transmitting 10%. 2 absorbance absorbs 99% transmitting 1%.
Heinz Hug’s measurements on a Bruker IR spectrometer showed CO2 at sealevel over the P and R branches has an absorbance of 0.125 abs/meter. At the 80 km altitude you claim the air pressure is 0.01 torr = 1.3e-5 atmospheres. At this altitude, assuming CO2 is well mixed, the absorbtivity (which matches the emissivity) will be 1.6e-6 abs/meter. A one abs column which will have an emissivity of 0.9 compared to a black body being 1 will be 1/1.6e-6 meters = 625 km, far more than the distance down to the surface. Eike is EXACTLY right, the pressure is far too low for emission at that altitude.
The plots I have seen of the top of atmosphere radiation to space taken by Nimbus 4 show black body overlays and the show an emission temperature to space of 220K which matches the temperature of the tropopause except at the peak of the Q branch where the temperature is slightly higher because the emission is coming from the stratosphere. The conflicting issue is the claim that CO2 is well mixed throughout the stratosphere. If that was the case there would be about 100 abs above the tropopause so emission would be from higher in the stratosphere where the temperature is warmer. The clue is Eike’s excellent observation that emission from the peak of the Q branch shows higher emission temperature which gives a clue to where the last vestiges of CO2 is and its still in the low stratosphere so CO2 is pooled in the lower stratosphere. Not unexpected since the stratosphere is very calm and CO2 is much heavier than air.
By the way , just thought I would mention I spent 40+ years doing research for a large multinational spectroscopy company.
Michael, from W&H:
Refer to the paper for the equations, they are straightforward. At 667.4 cm^-1, tau, the emission optical depth (eq. 38, 39) is 51,688 and z is 84.8km. W&H use very conventional definitions, I’ve seen them in many papers of this type. Attached is their plot. Their data on GHG vertical distribution is also shown and referenced.
You are using one dimensional data to refute a 3D argument, the academic equivalent of bringing a knife to a gunfight. Read the paper, go through the math, it is rock solid.
Eike, I’ve checked W&H’s calculations and they are correct. In the CO2 divot the emissions to the satellite are from 84 km and none from lower than that. As CO2 increases to 800 from 400 ppm the only thing that happens is the divot broadens slightly, so that some extra radiation on either side of the divot is blocked. This is not ambiguous or an opinion, this is completely verifiable, basic physics.
Eike, I think you mean the spike in the center of the CO2 divot. That is a result of an unusual part of the CO2 absorption spectrum. I’ve attached a plot.
Your remaining point about 8-12 km, the temperature there is around 220K. The emissions from the bottom of the CO2 divot are much colder than that. Less than 200K. The density of the atmosphere at 84 km is not too low to emit that much radiation, it is exactly the right density. At those frequencies, radiation is blocked nearly to the TOA. The emission altitude is determined by frequency, so an average emission altitude is very misleading.
Dont know if this is going to work, I have tried to attach an image. It is a plot of top of atmosphere radiation to space from Nimbus 4 along with black body temperature profiles overlayed. As you can see the emission temperature in the CO2 band is consistent with the temperature of the tropopause
The temperature you show is lower than the temperature of the tropopause in the standard atmosphere used by W&H. See Figure 2. But determining the emission height of a spectra involves much more than just the temperature, I don’t want to get into the math here, it is explained very well in the paper if you’ve had a class in calculus. Just read the paper.
Andy; you keep simply reiterating the W&H paper as a defence without making any attempt to address the contrary points being made. So lets make it really really simple. There is no doubt whatsoever that the temperature at the tropopause is colder than at both lower and higher altitudes.
Question, how does the temperature at that altitude remain colder than its surroundings without as you claim losing energy to an even colder sink (space). Are you suggesting net heat flow from the cold tropopause to the warmer stratosphere? Are you suggesting the tropopause remains cold without losing energy? What about the energy being radiated into it from the troposphere and stratosphere? If you have an answer, could we use it as a super efficient air conditioner in our homes? After all a region which can remain colder than its surroundings without any heat pump would be a fantastic cool store.
By the way Andy; you say
“But determining the emission height of a spectra involves much more than just the temperature”.
Virtually any GHG species in our atmosphere is so far into saturation it is going to look like a black body emissivity=1 at its absorption wavelength. All that changes with concentration is the depth of the emitting layer. Given that, Planks law precisely links emission intensity to temperature, thus if you know the emission intensity you know the temperature and if you know the temperature you know the emission altitude. The only time there would be uncertainty would be if there were 2 altitudes with the same temperature. So I have to say I do not agree with your claim.
Michael, You are being silly, or perhaps willfully ignorant. You claim to know something about radiation and spectra, but then write stuff like these two comments. Not sure what to think.
This is very near the top of the atmosphere.
It’s different for every frequency. W&H’s model matches satellite observations almost perfectly. See Figure 3. Spend less time writing transparent gobbledygook and read the paper.
To illustrate the power of CO2, we can use the University of Chicago MODTRAN, attached is the spectra for 0 ppm, next I will show the spectra with 1 ppm and then 10 ppm.
Point3: “CO2 has about the same concentration from the surface to the mesosphere”
Now I get it. Concentration is the amount of molecules in a given volumen, expressed in g/volumen or mol/volume. ppm is the relation to other molecules in our case O2 and N2. The CO2,O2 and N2 concetrations (mol/volume) are dropping exponatially in our athmosphere. Because pressure is dropping exponatially with altitude.As the air gets thinner and thinner the ppm´s stay the same because they are all dropping at the same rate. Absorbtion is dependet on the concentration of gas (not the ppms) and the distance ligth has to travel through it.
Here is 1 ppm
Here is 10 ppm
Sorry here is 10 ppm
Finally 100 ppm, 25% of today. The website is here:
MODTRAN Infrared Light in the Atmosphere (uchicago.edu)
Spend some time with it and you will see why W&H are correct. Notice that by 100 ppm the CO2 divot has almost reached 220K. Most of what you have written is true, it is just irrelevant to my post or their paper. Like I said, you are examining a 3D problem with 1D tools.
Andy May:
You clearly do not understand what a black body is
You clearly do not understand what entropy is
You claim the CO2 emission temperature of around 215K is too low to be coming from the tropopause yet several websites sites I found in less than 2 minutes searching clearly state the tropopause at the poles is around -50C (223K) and at the equator it gets down to -80C (193K).
I point out the measured absorbance of CO2 at sealevel is 0.125 abs/meter measured so at 84 km assuming co2 is well mixed it will be .125 * (.01/760) = 1.6e-6abs/meter or 0.0016 abs/km. Since 90% of the emission to space comes from the last 1abs of the column that implies an emission depth of 625 km which is clearly ridiculous. You obviously do not understand this, implying you do not understand the concept of absorbance.
I ask how the troposphere can remain colder than its surroundings if, as you claim, no energy is lost to space from that altitude. An extremely valid question which you do not answer other than to claim the question ridiculous. I can only assume either you don’t understand the question or you don’t know the answer.
You clearly don’t understand the operation of heat engines and specifically the need for a cold junction where energy is lost from the system at the end of the expansion phase. This is at 12-18km yet you claim energy is only lost at 2.6km and 84 km neither of which would support a convective loop from sea level to 12-18 km.
You don’t understand the point of water having a huge number of very closely spaced lines so that the indicated emission height is really an average of a bimodal distribution – sea level between lines and close to tropopause at line peaks.
Your approach when your writings are questioned is simply to declare the questions meaningless gobblygook and irrelevant rather than trying to address them. I can only assume because you don’t know enough to address them or maybe even understand them in the first place.
Your approach when dismissing the questions as meaningless gobblygook does not work is to become insulting towards the questioner.
When I comment, I start off by assuming the author knows what he is talking about and is willing and able to discuss sensible critique. You have now convinced me that this assumption does not apply to you so there is no point in continuing this interaction.
I’ll ignore the personal attacks, but on your specifics.
I never wrote that. W&H’s calculations demonstrate that the altitude of emissions to space (ze, computed from the optical depth tau-e, see equations 33 to 39 in the paper) is dependent upon the radiation frequency. Radiation at some frequencies comes from the surface or troposphere. At some specific frequencies, like 667.4, it comes from very high in mesosphere.
You seem to have latched on to temperature as the only variable in the calculation, it isn’t. The atmospheric temperature profile and the profile of the GHG concentrations, as well as the atmospheric density, latitude, and especially the frequency all play large roles in the calculation.
Back to gobbledygook. Tau=51,688 (optical depth) and ze (emission level, as defined in the paper) is 84.8km.
tau-e, the emission optical depth, from which ze is computed, is the level where half of the energy flux at the top of the atmosphere (~86 km in the mid-latitudes) comes from (eq. 38). So, at a frequency of 667.4, half of the total emissions received at the satellite come from 84.8km.
Perhaps you don’t understand calculus, in which case, further discussion is pointless.
Dear all,
thanks for the many replies. Getting more than one opinion I tried to read the paper and to be honest I ignored all calculations (sorry no degree in physics). Andy is probably right with his claim that the math is correct and at this frequency 667.4 the emission comes from 84.8 km.
And my idea of completely ignoring the mesosphere may be a little bit too simple. But the paper also claims this to be an “extreme blanket frequency”.
And in figure 6 it claims:
“An exception is the band of frequencies near the center of the exceptionally strong bending-mode band of CO2 at 667. Here doubling CO2 moves the emission heights to higher, warmer altitudes of the stratosphere, where molecules can more efficiently radiate heat to space.”
The increase in w/m2 at around 667 is emitted from a hotter stratosphere, it maybe much more complicated on a line by line view.
The problem I have with the WUWT article is following statement.:
“The marked altitude of 84.8 km, in the middle of the CO2 caused divot in the energy curve, means that the emissions at that frequency range, roughly 609 to 800 cm-1, come from that altitude.”
For me this sounds like the whole CO2 emission to space comes from a fixed layer at 84.8km.
And because the mesosphere is only cooling with height I don’t find any reason for the increase in radiation in the middle of the 15µm band. Nor do I find any explanations for the CO2 cooling effect over antarctica.
Sorry I still don´t get it
Thanks a lot for your time.
Eike,
It is complicated and very hard to explain without the math. I did the best I could. Both the paper and the post are correct. The whole range of frequencies from 609 to 800 have an emission height in the mesosphere, but not exactly 84.8 km, that is the example calculation for 667.4 cm^(-1). It varies by frequency.
The cooling effect in Antarctica is simply because the CO2 is at a higher temperature than the surface, that causes the CO2 greenhouse effect to reverse and cause cooling. Remember thermal energy (“heat”) always moves from warmer bodies to cooler bodies, in the case of Antarctica, the flow is from the atmosphere to the surface, so any radiation from CO2 to space or to the surface cools the atmosphere. This is opposite of what happens most other places.
The key thing to remember is that the emission height is frequency dependent, there is not just one height. I’ve seen many PhD climate scientists and physicists make the same mistake.
Play around with the U of Chicago ModTRAN, it helps visually show the complex math:
MODTRAN Infrared Light in the Atmosphere (uchicago.edu)
Hi Andy,
if I replace all CO2 molecules from 0-1km with the CO2 molecules from 84-85km the ppm´s drop from 400 to 0.0036. ModTRAN spectra attached.
Interesting, thanks.
Andy May wrote:
“Both the frequency and the power emitted by molecules are determined by the molecule’s temperature.”
You might want to clarify the above.
That applies to blackbody radiation ( which is emitted by solids, liquids, and gases of sufficient density that blackbody radiation emission/absorption swamps spectral radiation).
For spectral radiation, the frequency (and hence wavelength) is a function of the differential between the energy of the two quantum states (the original higher quantum state, and the new lower quantum state which is quantum jumped to), whether that quantum state be a rotational mode quantum state, a vibrational mode quantum state or an electronic mode quantum state.
So something along the lines of:
“For blackbody radiation, both the frequency and the power emitted by an atom/molecule are determined by that atom’s /molecule’s kinetic temperature.”
The above also delineates that there’s a difference between kinetic temperature (the temperature associated with the kinetic energy of an atom/molecule, this is a single number associated to a single temperature, not an average) vs. the thermodynamic temperature (the average temperature associated with the average kinetic energy of an assemblage of atoms/molecules with kinetic energy distribution describing a Planckian curve).
Jimmy,
Well said! Thank you. I was sloppy in my writing. The math makes it so easy. Translating the math into words is hugely difficult.
How much would an additional 3 w/m2 of forcing cause the temperature to increase?
Just asking.
That is the conversion where all the mischief occurs. The radiative forcing can be calculated fairly accurately, but the temperature response can’t. Recent estimates based on data suggest 0.1 to 0.2 degrees per W/m^2. The IPCC modeled values are much higher, 0.5 degrees or more. No one knows.
Climate Sensitivity to CO2, what do we know? Part 1. | Andy May Petrophysicist
Thank you for that info.
The column densities shown in Table 2 interchange the values of H2O and CO2 in Table 1 of the W&H paper. The paper shows H2O having the largest column density while Table 2 shows the opposite.
Kevin, You are correct, I’m sorry, I will fix that straight away. Thanks.
Thanks Andy. I forgot to mention I learned a lot from your article. Just this piece of the climate puzzle is complex.
I was surprised to learn that while CO2 and H2O are heavily saturated, the interaction between the gases is small. Referring to Col 2 of W&H Table 2, the cross interaction reduces forcing from 148.7 to 137, a reduction of just 8%. This is because the absorption bands are so narrow, even including the pressure broadening. I have frequently heard that GHGs block each other, but it’s a small effect.
I guess I should return to grade school:
“But this is not tough. This is simple. Kids at the earliest age can understand this.”
–John Kerry
Thanks again, Kevin