The amount of energy leaving the planet is nearly identical to the amount of solar energy being received. (Radioactive decay in the interior of the Earth makes the outgoing number slightly larger.)
Without greenhouse gases, the surface heat would immediately radiate back into space, and the atmosphere would be very cold. Greenhouse gases impede the return of energy to space. In other words they act as an insulator. They absorb photons of certain wavelengths, excite the molecules, and heat them. Many of these excited molecules then pass the heat on to neighboring molecules.
Because of these insulators known as greenhouse gases restricting the energy flow, in order to maintain energy equilibrium, the temperature has to rise near the surface – because heat flow is proportional to the difference in temperature. Increased temperature near the surface causes increased LW radiation, increased conduction, and increased convection – all needed to maintain equilibrium.
It is called conservation of energy.
Yes, but adding CO2 is like adding extra glass to a greenhouse. If the glass already blocks all the IR, adding more glass won’t block more IR.
Steven from what I’ve read here and elsewhere, this is the “knee effect”.
I had this discussion with my smart but poorly-read brother-in-law, and couldn’t find good science papers explaining it.
Do you have a references for it that I can pass on to him (and others)?
It’s intuitively correct–after two or three blankets, adding more makes almost no difference. But I can’t find a good paper on it; perhaps the effect has a different name in the research?
The knee can be seen on the left side of the graph. As you can see, the effect of CO2 is very minor. RRTM is one of the standard models used by weather and climate modelers.
Glass and CO2 do not behave in the same way. Come on thats childrens stuff.
Both inhibit heat transfer from a warm surface up to cold ambient. Glass does it primarily by inhibiting convection, CO2 and H2O etc. by inhibiting radiation.
They both block IR.
If glass truly blocks IR how did Hershel do his experiment with the prism?
Standard glass blocks longwave (far) IR (longer wavelengths than about 4um) but is highly transparent to shortwave (near) IR. Herschel was working with near IR (just outside visible red).
There are many kinds lf glass. Cheap window pane glass blocks most of the IR.
“Cheap window pane glass” (what I called “standard glass”) lets through the vast majority of the shortwave IR found in sunlight. That is why you can buy special films to apply to this glass if you want the visible light to come through but you don’t want the additional energy from the SWIR heating your interior space.
As I’m sure you are aware, greenhouses retain heat by supressing convection. They aren’t heated via “back radiation.”
It’s a shame scientists keep referring to what happens in the atmosphere as a “greenhouse effect.” It should be re-labeled the “atmospheric effect.” It in no way resembles what happens in a greenhouse and is very misleading.
As most folks on this forum know, the primary “greenhouse gas” is water vapor. But it is ignored by the IPCC and climate alarmists because it can’t be blamed on humans, taxed or turned into “water vapor credits” traded on a “water vapor exchange.”
The radiative warming impact of man-caused CO2 (which constitutes a small fraction of total CO2 emissions and whose warming is logarithmic in mostly the 15 micron wave band) is so tiny as to be unmeasurable. We are led to believe by the “experts” that scientists can differentiate between the warming effect of man-caused CO2 and the larger (but still small radiative warming impact) of natural CO2 via their different isotopic signatures. Bullshit.
The CO2 is no where near the amount that the atmosphere can hold. At below 300 ppm it blocks enough to keep earth at the right temp for life to exist. How much can it hold, I don’t know but it has been up to as high as 2,500 ppm. There is a threshold limit when the climate will change permanently. We don’t know if we are there yet but we better stop now.
You completely forgot that the effect of CO2 is logarithmic and we are past the”knee” in the curve so increases have very little effect. On top of that new observational research shows the curve is based on the wrong model for the ‘wings’ that give the added effect. The observational data shows the ‘wings’ are not as broad so the effect is even less than is shown in this graphs.
Data published by the IPCC on the diminishing effect of increasing CO2 concentrations. (Chapter 6. Radiative Forcing of Climate Change: section 6.3.4 Total Well-Mixed Greenhouse Gas Forcing Estimate) presented in graphic form:
Plants would prefer 1600 ppm CO2.
The above description is not the Greenhouse theory as argued by the IPCC, nor is it that espoused by Arrhenius. These theories where all about CO2, and perhaps CH4 and CFC’s; water vapour was also given a bit part to play. But Tony when you bring in terms such as conduction and convection then you are talking about N2, O2 and Argon as well as water in the form of clouds, which is NOT water vapour. Now I don’t disagree with this because all this is key to the atmosphere, but you confuse the hell out of everyone by being so insistent to include all of this in some broad greenhouse that works nothing like a greenhouse and is not the greenhouse the IPCC talks about.
Look in detail at the analysis of “mainstream” climate science and you do find that they acknowledge that water vapor is the main greenhouse gas in terms of radiative absorption.
The radiatively active gases, by absorbing energy low in the atmosphere and permitting losses to space from high in the atmosphere, set up a stronger temperature gradient that drives a lot of our weather.
II clicked on to the science daily link and they seem to say that increased temperature affects the ocean increasing the evaporation rate. In my experience this is not true because although radiation will penetrate the surface of water heat transfer by convection is blocked by surface tension. No “additional” heat goes into the ocean so when the sun goes quiet there is a pause just like now.
Steve Goddard says: “… i.e. greenhouse gas driven global warming theory simply does not work in a convective atmosphere.”
Any atmosphere make up will impede the flow of energy because not all gases can emit IR to the extent of CO2 or H2O. N2 or O2 when conductive heated cannot shed the heat via IR so must cool via convection per your statement.
My main disagreement with the global warming idea is the 33 K (C) because of CO2 plus any other rise they attribute to CO2.
I said no such thing. Misquoting me is totally unacceptable. Why would you do that?
“Conclusion : Even a huge increase in the greenhouse effect as we approach the surface of Venus, has no impact on the lapse rate. Observations on Venus demonstrate that increasing the greenhouse effect even by a large amount, has little impact on the temperature profile of a convective atmosphere. i.e. greenhouse gas driven global warming theory simply does not work in a convective atmosphere.”
Here is the full quote. From your “A Proof that Greenhouse Gas Driven Global Warming Theory is Incorrect”. Since we have a convective atmosphere I am trying to understand all you have been blogging lately.
I was talking about increasing greenhouse gases. Absorption of LW radiation is already saturated by existing greenhouse gases, so adding more greenhouse gases does little.
If there were no greenhouse gases, the atmosphere would be very cold and there would be essentially no convection.
By the way, there is no greenhouse effect on Venus. The greenhouse effect requires that solar radiation reach the surface, which it does not on Venus with the permanent, high level, cloud deck. The temperature at the surface is caused by gravitational compression, just as our basic starting temperature is caused by gravitational compression and then altered by weather and albedo differences. Also, there is no temperature difference from the sunny side to the dark side of Venus—it’s all gravity effects.
So I did not misquote. Thanks for the explanation.
Sorry, it looked like a quote someone else had said today.
…Anthony Watts claims SG never admits when he is wrong.
Well that looked pretty easy to me.
Everyone is entitled to their misinformed opinion
Well, yeah, it’s a greenhouse and good thing, too. IMHO “impede” “restrict” aren’t accurate descriptions. What CO2 absorbs can’t leave and therefore must add heat & temperature. The oceans compensate w/ more evaporation.
So a planet surrounded by an infinitely thick atmosphere of nitrogen would cool to absolute zero and we could run a perpetuum mobile between this atmosphere and the planet, great.
My two cents.
Under clear skies, the atmosphere facilitates the loss of thermal energy from the surface to the upper atmosphere. Under unclear skies, water vapor, dust and condensed water in clouds reflect the thermal radiation, impeding the loss of thermal energy from the surface. Calling this reflection “back radiation” or a “greenhouse effect” has created enormous confusion.
Comparing the atmosphere to a nursery greenhouse might be too simplified. On the other, love to visit greenhouses, how well would they function w/o CO2 and the obvious humidity?
Greenhouses would function perfectly without CO2 and water vapor, as the air heats largely by conduction and convection and very little by IR absorption. The glass roof’s biggest liability is that it is IR transparent and IR is lost to the outside as well by direct conduction of heat through the glass to the cold outside air.
In our atmosphere, conduction and convection transfer of energy accounts for about or more than 85% of the surface energy budget. It astounds me that everybody focuses on just one aspect of energy movement and preferentially ignores the other larger effects. It is well known that spacecraft have to shed energy and the only way that can happen is by IR radiation, which is not an efficient method. This is why they have to have many protrusions to create more radiative surfaces.
You COMPLETELY ignore conductive heat transfer! This leads to convection and warm breezes. IR radiation is only about 15% of the energy budget from the surface. The rest is all conductive/convective and the heat of vaporization from evaporation (the latter is not sensible as heat).
But those conductive/convective and evaporative heat transfers would not occur (on average) without GHGs inhibiting radiative transfer from the earth to space.
A transparent atmosphere has no way of exchanging power with space. It could only exchange power with the surface. Therefore, in steady state conditions, it could not, on average over the long term, accept power from the earth through these mechanisms – it must be putting back as much as it takes, or it would warm without end.
It is only because the earth’s surface is on average warming than the bottom of the atmosphere due to the reduction of radiative heat transfer to space that we get net transfers from the surface to the atmosphere through these means.
“But those conductive/convective and evaporative heat transfers would not occur (on average) without GHGs inhibiting radiative transfer from the earth to space.”
Why ? Surely the solar radiation will heat the surface and evaporate water no matter what.
So the argument is kind of irrelevant.
Yes “A transparent atmosphere has no way of exchanging power with space” – so therefore aren’t you actually arguing that more GHGs will result in greater atmospheric radiation to space not less ?
After all 99% of the atmosphere has little interaction with IR either by absorption and emission as claimed BUT it is stretching credibility to claim 99% of the atmosphere does not absorb sufficient energy from the surfaces to reach the same temperature as the ~2% on average GHGs.
Trenberth et al argue GHGs are responsible for ~83% of the IR emitted by Earth to space with direct surface emission being ~13%.
Surely more GHGs mean more IR to space.
Let’s take it step by step.
A transparent atmosphere has no mechanism for transferring energy to or from space. Not conduction. Not convection. Not radiation (because transparent means no emission or absorption).
This means the only thing a transparent atmosphere can transfer energy to or from is the planetary surface.
This further means, that in anything approximating steady-state conditions (and this includes day/night variance) it cannot continually transfer energy in the same direction to or from the surface. In the simplest case, with a constant surface temperature, when the base temperature of the atmosphere reached the surface temperature, all heat transfer would stop. With day/night cycles, the atmosphere would absorb energy from the surface during the day, and return an equivalent amount during the night.
From this it follows that the planetary surface cannot transfer energy to or from the atmosphere continually in the same direction.
This means that the only way the surface can achieve energy balance is to radiate as much energy to space (through the transparent atmosphere) as it receives from the sun, averaged over time and area. It would stabilize at the temperatures to do this.
Now add some radiatively active gases to the atmosphere. These can radiate to space. So they cool, right? Not on balance. Because their absorptivity matches their emissivity at any and all wavelengths. So they cannot emit at a wavelength without absorbing equally well at that wavelength. This absorption keeps the surface from radiating directly to space.
The atmosphere is sandwiched between a warm planetary surface and the effective “cold” of space (in that space radiates to earth as much as a solid surface very near absolute zero). So it must be between them in temperature. The warm surface radiates more at any wavelength than the atmosphere does, and the atmosphere more than space. This sets up a temperature gradient in the atmosphere.
Since the surface is no longer radiating directly to space, but to an atmosphere at an intermediate temperature, its heat transfer is reduced (whether you want to think of it as a one-directional net power flux or the difference between two opposing fluxes does not matter). The surface temperature must increase to restore energy balance.
I agree with MarkT.
Here is my contribution. I am only the messenger, please don’t shoot.
THE MIXTURE OF AIR;
So what about mixtures? The terms ‘atmosphere’ or ‘air’ are abstract terms that can be described as a
“mixture of different molecules in their gas phase that are NOT connected by any type of
chemical bond and they do not interact with each other”. That mixture, i.e. atmosphere or air, does
NOT have any physico-chemical property itself but it reflects properties of individual molecules that
are part of that ‘collection’. Therefore, the property of any mixture can be calculated or derived from
the contribution of each molecule towards that mixture:
Contribution Index for molecules making-up the mixture called ‘air’: N2=0.79, O2=0.21,
Every single property of our atmosphere can be explained by
its two major contributors, the molecules of N2 and O2. It follows that CO2’s contribution cannot be
detected by any standard instruments since every property of CO2 in its pure state has to be multiplied
by 0.0004 to reflect its own contribution to the resulting property of that mixture! The set of measured
properties, heat capacity Cp and Cv plus density, for molecules N2, O2 and CO2, and also for air, are
listed in Table 1:
[sorry, the table did not print]
The definition of heat capacity is ‘the amount of heat energy in kJ needed to warm 1kg of gas by
1O K’ and since its importance in experimental sciences, very accurate measurements have been done
for the most common molecules. Please note that contrary to the GHGT, every molecule has a heat
capacity with molecules N2 and O2 in their pure state absorbing more heat than CO2 in its pure
state. If the law of mixtures works we should be able to derive the heat capacity for air from the
measured heat capacity of its two major contributors, N2 and O2. Please note: Cp represents heat
capacity at constant pressure while Cv is at constant volume.
Exercise 1: Deriving the heat capacity of air at a constant pressure, Cp, from the measured heat
capacities of N2+O2 alone:
Contribution for N2: (78.0/100)*1.04(Cp) = 0.81 kJ/kg
Contribution for O2: (21.0/100)*0.92(Cp) = 0.19 kJ/kg
Total contribution (calculated) N2 +O2 = 1.00 kJ/kg Measured (air): 1.01 kJ/kg per 1K
Exercise 2: The heat capacity of air at constant volume, Cv:
Contribution for N2: (78.0/100)*0.74(Cv) = 0.58 kJ/kg
Contribution for O2: (21.0/100)*0.66(Cv) = 0.14 kJ/kg
Total contribution (calculated) N2 +O2 = 0.72 kJ/kg Measured (air): 0.72 kJ/kg per 1K
If we want to calculate the contribution of CO2 (used as 0.04% or 400 ppm for simplicity) towards
any property of air all that is needed is to multiply that property with the ‘CO2-contribution index’
(0.04/100) which is 0.0004:
The contribution of CO2 towards the heat capacity of air: (0.04/100)*0.84 (Cp) = 0.00034 kJ/kg, or
in terms of CO2 contribution towards 1K of warming, 0.0004*1 = 0.0004K.
Therefore, for air to warm by 1K, CO2 contributes exactly 0.0004K,
If we now look at the air mixture from N2+O2 vs. CO2 ratios:
•999600 ppm of air belong to N2+O2 molecules, while 400 ppm to CO2 molecules (2500 : 1
•From a single CO2’s molecule point of view, 1 molecule of CO2 is surrounded by 2500
molecules of N2+O2
Al good job. Now look at the capability of air to heat dirt/rock/earth. The density of the earth precluded that happening.
Al: Take a liter (or half-liter if that’s what you have) in a glass kitchen measuring cup. Start adding drops of food coloring to it one at a time, allowing each one to mix well. A drop of a water-based liquid is about 50 microliters, and the dye in the drop is not more than 20% of the drop. Let’s call it 10 microliters.
So each drop adds 10 ppm to the liter of water (or 20 ppm to the half liter). But even a single drop significantly alters the radiation absorbing properties of the liquid in the cup. Your eye can detect it easily.
Now repeat this in a dark room and use a laser of a different color from the food coloring (e.g. a green laser pointer with red food coloring). Shine the laser through the cup onto a white backdrop. You can easily see how these few parts per million of colorant significantly attenuate (absorb) the radiation from the laser over just a few centimeters. The energy in the absorbed radiation is added to the water.
No one is arguing that these small additions of GHGs to an N2, O2, and Ar atmosphere have any significant effect on properties like Cp or Cv. But they can significantly alter the radiative transmission properties of the gas, just like the food coloring in water.
You cannot equate the optical density of water with the optical densities of gases. In order to equate the two the optical path needs to intersect the same number of molecules in each medium and the angles and path lengths between interactions need to be the same. Those things don’t scale. That means your liquid example is 3 orders of magnitude denser than air. There are also massive differences in scattering and absorption (refraction indexes and Abbe values) between gases and liquids due to the more closely packed molecules.
The other problem with your example is that you are using a line emitter (a laser) perfectly tuned to your absorption material (your dye which does not behave like a gas either) when in reality the absorption of IR by our atmosphere is miniscule. They are extremely small percentages of very narrow bands of the energy coming in to our planet and leaving from the ground. IR and Thermal cameras work very well as do IR telescopes that see through the full depth of the atmosphere. Gases are lousy absorbers and emitters of radiant energy at the pressures found in our atmosphere. Most of the radiative energy transfers in our atmosphere are due to water vapor (which is NOT a gas below 100°C and should not be treated as one) and suspended particulate matter which have emissivities high enough to register.
Argon is the third most prevalent gas in our atmosphere and it’s attenuation/absorption of green and blue visible light is higher than CO2’s in the IR range, but is not noticed at all… and we can use our eyes. At 1% it is 30 times more prevalent than CO2 and there is much more energy available to it from the sun, but no one is blaming argon for heating up the planet even though it contributes more energy than CO2. (Maybe that’s why the EPA’s trying to sneak it onto a banned list… conspiracy time.)
nielszoo: Oh dear, where to begin…
“Water vapor is not a gas below 100C and should not be treated as one.” Right there, you have totally discredited yourself. Just because we tend to use the word “vapor” to describe the gaseous state of a substance that can also be a liquid at that temperature and pressure does not mean the “vapor” is not a gas in every technical sense.
You say my analogy of a few ppm of food coloring in water is not appropriate because the water is so much denser than our atmosphere. Let’s look at that. Water is about 1000 times denser than the base of our atmosphere. But the colorant provides significant radiative attenuation over a range of 100 mm or so. Let’s multiply that by 1000 to account for the lower density of air, and we would see significant attenuation over a range of 100 meters, a very small part of the height of the atmosphere.
You object to my using a monochromatic laser to show the attenuation, but you miss the first part of the argument, that a very small amount of colorant significantly changes the transmission of broad-spectrum white light. I suggested the laser more to get a focused beam of light than to get a single wavelength.
You say, “the absorption of IR by our atmosphere is miniscule.” Hogwash! There are broad bands of the longwave (far) infrared that the atmosphere is completely opaque to. There is a reason we spend billions of dollars putting IR telescopes into space (some of which I’ve worked on).
You claim that the argon in the atmosphere provides significant attenuation of visible light. I have yet to find a single reference that confirms this, and I cannot think of a single theoretical reason why a monatomic gas like argon would even be able to do this.
I could go on, but what’s the point?
Curt, sorry to burst your bubble but the properties (at our atmospheric pressures) of a vapor below the material’s boiling point are very different from the properties at temps above the boiling point. The size, spacing and motion of molecules in a material have massive influences on how radiation is absorbed, emitted, refracted, scattered and reflected. I see you have little knowledge about optical systems (or are not using that knowledge) so I don’t really know where to begin. I design both visible and IR imaging systems for a living so I work with this stuff on a daily basis. Simplistically deciding that density alone is all you have to account for is where you went wrong. All you need to do is look at a cloud, a steam plume and a puddle to see how the different states of a material effect its optical properties. Another huge problem with your dye analogy. A dye is a material that’s designed to absorb a specific range of frequencies very very well. Comparing that to a gas whose absorption efficiency is several orders of magnitude below ANY solid or liquid material, much less one used as a dye or pigment, is extremely misleading. Leaving aside all of the refraction path angle problems, scattering etc. for a liquid, your dye concentration needs to be lowered by many more orders of magnitude before it even remotely approaches the extremely poor absorption efficiencies of the “greenhouse” gases you are trying to mimic.
I believe you misread my Argon comments. I did not “claim” Argon absorbs a significant portion of our visible spectrum. Please re-read what I wrote. Argon emits and absorbs strongly in the green and blue portions of the visible spectrum. If the so called “greenhouse” effect, where atmospheric gases were absorbing and re-radiating IR, was valid then the exact same effect would work with shorter, visible wavelengths. Air warmed by mechanical heat transfer from the planet’s surfaces would then be emitting blue and green light from warm Argon in the atmosphere… and absorbing those wavelengths from the sun. Obviously that doesn’t happen and that’s my point, if you are going to try and “model” atmospheric absorption of radiation you need to account for all the radiation coming in and all of the absorption properties of ALL the gases present as that energy has to go somewhere. Again, I doubt that Argon contributes much to atmospheric heating, but its inputs are far higher than CO2’s are.
Our atmosphere attenuates, to some degree, every frequency of energy coming in to it. The so called “greenhouse” gases absorb in wavelengths that make it all the way through our atmosphere just fine and dandy, again, why FLIR devices work. (Water vapor is the exception as its emissivity is drastically higher.) Mid and long wave infrared, where the greenhouse adherents claim CO2 and CH4 are adding massive amounts of warming, is at 15µm and shorter and a great many ground based systems work well there and our atmosphere is NOT even remotely opaque in those bands. Far IR out to 1mm is a different kettle of fish no one is (yet) trying to claim some man caused calamity using this energy. Note that we also put visible telescopes in orbit as well to avoid atmospheric interferences.
nielszoo: I missed this when you originally posted it, but it is so full of errors that I can’t let it go.
Are you seriously claiming that water vapor in air at 99C is fundamentally different from water vapor in the air at 101C? Really? Do you even understand what the boiling point of a liquid means (and does not mean)? You give examples of liquid water — fog and puddles — do you really believe that water vapor below the boiling point is equivalent to these?
I have been looking, without any success whatsover, for any reference that shows any noticeable, let alone significant absorption bands for argon in the visible spectrum. While I can find a few somewhat significant absorption bands for H2O and O2 in the visible spectrum, I can find none at all for argon. Perhaps you can point me to some?
These same references show virtually complete absorption over significant bands of the thermal infrared due to H2O and CO2. The differences are stark.
There is a complete difference in the transparency of the atmosphere in the visible spectrum, where there is mild attenuation and distortion, and wide bands of the far infrared, where the atmosphere is completely opaque.
While space telescopes for the visible spectrum avoid this attenuation and distortion, the far larger mirrors now possible with controlled multi-segment mirrors to overcome mild attenuation, and the new deformable secondary mirrors to overcome distortion, earth-based telescopes match the performance of space-based telescopes in the visible spectrum, and at 1/10 the cost. I have worked on both the manufacturing and control of these telescopes. A few years ago, astronomers proudly sent me a copy of the first picture of the rings of Uranus taken from the earth’s surface to thank me for my help on the control of the deformable secondary mirror.
However, the complete absorption of the atmosphere to wide bands of the far infrared due to H2O and CO2 cannot be overcome from the surface. So people are still spending billions to design and launch new space-based infrared telescopes.
I prefer a different analogy Curt. Make up a 1000piece jigsaw. This represents a volume of air. Stick your finger over less than 1/2 of one piece of the jigsaw ,which represents the volume of CO2 in that parcel of air , and see what effect that has on the temp. of the rest of the jigsaw.
When you say there is very little CO2 in the atmosphere, and use it as an argument that it can’t be a greenhouse gas because there is too little, you are making a false argument. In fact, all it takes is 20 ppm for CO2 to have a huge greenhouse effect. This is a wrong argument and you should never make it again or you’ll look like a fool.
Bingo! Here is a link to specific heat table
hope it works for you.
Nope, that’s not what the IPCC says about incoming and outgoing. It’s not equal. It’s 363 w/m^2 incoming, 240 w/m^2 being retained, and only 163 w/m^2 being released. And if we don’t act now with additional increase in co2 the planet will reach a tipping point where we will have a runaway green house effect. Was that when co2 was 350 or 370 ppm? It’s very easy to do the math and see when that point will or has been reached either now or in the past.
The problem these clowns have is that a number of times in pre-history CO2 has been much, much higher than today and the Earth didn’t fry. Instead, it just got greener due to all the plant food.
So, today we have the greenies engaging in the ultimate foot-shooting exercise, by trying to limit that which promotes plant growth. The stupidity is mind-boggling.
When they were trying to limit carbon (soot) and industrial chemical pollution, I was on their side. When they (like good arts and social science graduates) moronically moved on to C + O2, they secured their place in history alongside the witch-burners.
The IPCC diagrams are well balanced (which is not the same thing as saying they are meaningful or precise):
Using one recent version of the Kiehl-Trenberth diagram, all values expressed in W/m^2, averaged over time and area, we see:
Top of atmosphere:
341 solar radiation
102 reflected solar
239 longwave thermal
Net: 0 (balance)
161+23=184 solar radiation
333 longwave thermal
Total incoming: 517
23 reflected solar
17 thermal (conductive/convective)
396 longwave thermal
Total outgoing: 516
Net: +1 (almost balance)
All of the real controversy is how well we know that +1 (I think not well at all).
… and I love how they all expect this to be some zero sum game. Every wind current, updraft and down draft is powered by energy from the sun… where in their “models” do they account for the energy that powers the motion and frictional losses of 5,300,000,000,000,000 metric tons of mass… 24/7/365? (That’s 5.3 quadrillion metric tons.)
But there isn’t 184 or 341 solar radiation and averages don’t “cut it” and they are not really meaningful
Half of the Earth is constantly irradiated by the solar radiation which is approximately 1370 W/sqm TOA and using standard solar photovoltaic calculations the insolation at the surface quoted by Trenberth et al as 1614 W/sqm is exceeded at latitudes from 83 N to 83 S assuming clear skies as well as 83 E to 83 W – most of the globe continuously.
This is actual reality – anyone who owns solar panels can confirm the figures quoted from Trenberth are not real and have limited use other than in one simplistic calculation – the calculation of the theoretical blackbody temperature of the Earth.
To claim the solar radiation is 184 on average is misleading and in no way represents the thermal response of the Earth continuously absorbing up to 4 times that figure.
Rosco: You say, “Half of the Earth is constantly irradiated by the solar radiation which is approximately 1370 W/sqm TOA.” And the other half of the earth is constantly NOT irradiated because it is nighttime there, so has 0 W/sqm TOA.
And that 1370 W/m^2 TOA is valid only for the (small) portion of the earth directly facing the sun. It falls off rapidly as the angle changes. At the equinox, when the sun is directly over the equator, the TOA insolation at 60 north or south latitude at noon is half of that (cos60=0.5) and lower than that the rest of the day.
If you take the 1370 W/m^2 TOA multiplied by the Pi*R^2 area of the disk it intercepts and then you divide it by the 2*Pi*R^2 area of the hemisphere surface it reaches, you are down to 685 W/m^2 TOA averaged over the hemisphere. Then if you include the 2*Pi*R^2 area of the nighttime hemisphere that is receiving 0 solar insolation, you are down to 342 W/m^2 TOA averaged over the full surface of the earth.
And we haven’t even mentioned clouds yet. Clouds and other aerosols reflect over 25% of the TOA insolation back to space. This takes us down to about 240 W/m^2 absorbed by the earth and its atmosphere, averaged over the full surface of the earth over day and night.
Even with clear-sky conditions with the sun directly overhead, only about 3/4 of the solar insolation makes it to the earth’s surface, which is why solar panel makers say the peak insolation they can receive is 1000 W/m^2. This takes us down almost to 180 W/m^2 reaching the earth’s surface, averaged over the full surface of the earth over day and night, and about 20 W/m^2 of this is reflected, leaving about 160 W/m^2 absorbed on average.
You may want to think of all of these numbers multiplied by the surface area of the earth in m^2 to get the total number of watts in each case.
Of course, you cannot simply get resulting surface temperatures just using these average values, because of everything else that is going on, particularly the non-linear relationship between temperature and emitted power flux density.
You see, we agree after all. It has a stabilizing effect, not destabilizing as alarmists are trying to make it.
Steve…The “blanket” analogy of the atmosphere acting simply as an insulator, has a double edge to the sword. The source of heat is outside the atmosphere. I always thought that a hot-water cylinder kept water inside hot.,(note..heating element required), until I met this Egyptian guy who said. “Oh , we use those back home to keep the water cool ” The atmosphere cools the Earth’s surface Steve. It gets to nearly 2500 degrees out there in the thermosphere.
Enough straw man arguments, thank you.
Steve…..you’re being obtoose, how much more can I tolerate this ; )
The source of body heat is also outside the atmosphere – the sun which grew the food you ate.
It’s called the “radiative greenhouse effect” Steve. I’m not eating and converting food to energy at the speed of light. At least I hope not.
ell summed-up Curt – we are (should be) talking TEMPERATURES here and not energy fluxes.
Reblogged this on Centinel2012 and commented:
Excellent summary, short simple and to the point!
All of the heat being moved around in Steve’s opening comments involves sensible heat. 0.24 Btu/lb-F for air 1.0 Btu/lb-F for liquid water. A watt is 3.412 Btu/h. The radiative energy of GHGs are measured in a few watts/sq m.
A pound of water evaporated from the ocean’s surface carries 1,000 Btu. How fast does it evaporate? How dry (not how hot!) is the air above the surface? It’s the water vapor/clouds/precipitation that regulates/motivates/demotivates (Look, Uncle Owen, this R2 unit has a bad motivator!) the atmospheric temperatures, not CO2 & GHGs.
Stefans Law states that all material increase emissions with a 4th power exponential Temp increase … that law is alledgedly universal across all phases of matter …. utter garbage … in the case of a Gas (Co2 in this instance) the emmission actually drops … water vapour behaves the same across all pressures … check any Thermometry 101 texts you wish.