Guest essay by Saburo Nonogaki
It has been said that the averaged earth surface temperature would be 255K if no green-house-effect(g-h-e) gases were contained in the atmosphere, and is 288Ｋ at present where the atmosphere contains g-h-e gases. The estimation of 255K is based on the earth’s long-term radiative equilibrium and Stefan-Boltzmann’s law which states that the total amount of radiative energy from a black body at absolute temperature T is proportional to T 4.
As the earth’s long-term radiative equilibrium will be reached also in the case where the atmosphere contains g-h-e gases, we obtain the following equation under the condition that the long-term input energy from the sun remains constant.
(1–a )T 4 = constant (1)
Here, T is the averaged earth surface absolute temperature and a the ratio of radiative energy retained by the g-h-e gases in the atmosphere to the total radiative energy. By replacing T in equation (1) with 255Ｋ and 288Ｋ, we obtain the following equation.
(1–0)×2554 = (1–a )×2884 (2)
From equation (2), we obtain the value of a as follows.
a = 0.385 (3)
Jack Barrett* has reported that, in the case of 100m-thick atmosphere, the doubling of pre-industrial concentration of CO2 will result in the increase in infrared absorption by g-h-e gases by 0.5%. The reason why the increase is so small is based mainly on the saturation tendency of infrared absorption by CO2. As the re-emission of a part of energy absorbed by g-h-e gases into the universe takes place, the increase in a is less than 0.5%. According to equations (1), (2) and (3), the increase in a by less than 0.5% results in the increase in T by less than 0.6K.
As the actual thickness of the atmosphere is about 8000m at ordinary atmospheric pressure, the saturation of infrared absorption by CO2 will be almost complete and the actual increase in a caused by the doubling of CO2 concentration must be much less than 0.5% and the resulted increase in T must be also actually much less than 0.6K.
*http://www.warwickhughes.com/papers/barrett_ee05.pdf (p. 1042)
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This is not about the answer, it’s about the method.
Recent estimates from IPCC (2007) say this value (the Climate Sensitivity) is likely to be between 2 and 4.5°C. But Sherwood Idso in 1998 calculated the Climate Sensitivity to be 0.4°C, and more recently Richard Lindzen at 0.5°C. Roy Spencer calculated 1.3°C in 2011.
See Carbon Dioxide and Global Warming (C. D. Idso and K. E. Idso. co2science.org, 1998), at http://www.co2science.org/about/position/globalwarming.php
See Taking Greenhouse Warming Seriously, at http://www-eaps.mit.edu/faculty/lindzen/PublicationsRSL.html
See Global Warming 101 (Roy Spencer, Ph. D., Principal Research Scientist at the University of Alabama in Huntsville – UAH), at http://www.drroyspencer.com/global-warming-101/
See Weak Warming of the Oceans 1955-2010 Implies Low Climate Sensitivity (May 12, 2011. Roy Spencer, at http://www.drroyspencer.com/2011/05/weak-warming-of-the-oceans-1955-2010-implies-low-climate-sensitivity/
See More Musings from the Greenhouse (February 19, 2012. Roy Spencer, Ph. D., Principal Research Scientist at the University of Alabama in Huntsville – UAH), at http://www.drroyspencer.com/2012/02/more-musings-from-the-greenhouse/
The direct link to Lindzen’s Taking Greenhouse Warming Seriously (.pdf, 968 KB) , is at
at http://www-eaps.mit.edu/faculty/lindzen/230_TakingGr.pdf
Rubbish! The 255k temperature has been picked because it is the estimated mean temperature of the moon. No other reason. Equations have been built around this assumption and make a mockery of science! Anyone with half a brain will realise that as the moon reflects a 1/3 less sunlight than the earth (albedo) that the 255k figure for earth without an atmosphere is idiotic! Dress up your equations however you like!
Second, I also don’t need to use complex equations to show by the greenhouse con men’s own theory that (assuming we accept their premise, which I don’t, but let’s play along) CO2 is spent. Simply take their 33K premise and the percentage of that amount that CO2 is supposed responsible for and after you have lampooned the “between 9% and 26%” figure that is cited for being so spread apart a bus could fit through it, draw a graph for the low figure and the high figure expressing the percentage of 33K in kelvin. That number will represent 0ppm of CO2. Now plot 280ppm (1860 levels) and the increase in temperature and today. Draw a line through the points! Anyone who can’t be bothered to do this should go back to selling snake oil until they’re thrown in jail!
Rubbish! The 255k temperature has been picked because it is the estimated mean temperature of the moon.
Rubbish! The estimated mean temperature of the moon is 271K. That is NOT where the 255K number comes from.
David , That’s real interesting to me because it’s within 3% of the 278.7 orbital gray body temperature , much closer than other estimates I’ve heard . I’d appreciate a reference .
That implies a ratio of about 1.11 between the Moon’s emissivity in the IR versus its absorptivity over the Solar spectrum .
Instead of using estimated mean temperatures if the Moon, why not use the actual measured temperatures?
http://www.diviner.ucla.edu/science.shtml
Hmm…. 206K – AT THE EQUATOR!
Looks like those estimated mean temperatures are a pile of donkey-doos.
Bob Armstrong;
That implies a ratio of about 1.11 between the Moon’s emissivity in the IR versus its absorptivity over the Solar spectrum .
>>>>>>>>>>>>>>
Albedo of Earth is about 0.3 and the moon is about 0.1 Slight variations in temp estimates depending on reference. Willis did a rather thorough write up on it a while back:
Anything is possible – suggest you read this as well. The problem is one of how you average a temperature that swings wildly to equate to SB Law.
http://wattsupwiththat.com/2012/01/08/the-moon-is-a-cold-mistress/
davidmhoffer (December 24, 2014 at 6:01 pm) links to an article regarding the Moon.
In a ddition to bearing in mind the very different and significant rotational spped of the Moon which has a substantial bearing on its temperature, It is well worth repeating the comment made by Bryan on that post and the guilty little secret:
Bryan (January 9, 2012 at 1:15 am)
The SB equation is misused by IPCC style Climate Science.
The Moon is a perfect example of this.
1. why after 14 Earth days does the dark side never reach absolute zero but stays some 90K above?
2.why after 14 Earth days does the Sunlit side never reach its predicted radiative max but stays well below it.
The guilty little secret of IPCC Moon Science is that to get anywhere near realistic temperature figures they have to include a substantial contribution from a GROUND HEAT FLUX in addition to the radiative fluxes.
The guilty little secret of IPCC Earth Science is that they refuse to include a ANY contribution from a GROUND HEAT FLUX in addition to the radiative fluxes.
If they did so they would find little use for the so called greenhouse effect.
Richard Verney;
1. why after 14 Earth days does the dark side never reach absolute zero but stays some 90K above?
Because the moon has a heat capacity and would take a lot longer than 14 days to reach absolute zero.
David , certainly your ( .9 solar absorption ; 1.0 emission ) producing your 271K matches the requirements for radiative balance . Does anybody have an measured absorptivity=emissivity averaged spectrum for the moon ? How temperature dependent is it ?
Whatever physical data are measured , they must be reconciled with the spectral data and energy balance with the Sun .
davidmhoffer
December 25, 2014 at 5:14 am
////////////////////
I am aware of your point. See Bryan’s comment : “The guilty little secret of IPCC Moon Science is that to get anywhere near realistic temperature figures they have to include a substantial contribution from a GROUND HEAT FLUX in addition to the radiative fluxes.”
But of course, planet Earth with its huge heat storage reservoirs (the oceans) and it significantly faster speed of rotation (which keeps the oceans well heated) is not similarly so treated. As bryan notes: “The guilty little secret of IPCC Earth Science is that they refuse to include a ANY contribution from a GROUND HEAT FLUX in addition to the radiative fluxes.”
Bryan goes on to conclude: “If they did so [ie., treat the Earth in the same manner as they treat the Moon] they would find little use for the so called greenhouse effect.”
David, it is worth looking at how quickly the surface of the moon cools soon as the sun dips below the horizon. It drops off a cliff. Very different to planet Earth with its huge storage heates (the oceans).
James Abbott
December 24, 2014 at 2:58 pm
Wow, that’s a blast from the past. You must have dug that one up out of the old pile of dumbest Warmist arguments. Sorry, but the null hypothesis remains that climate change is natural. So far, despite Warmists’ most fervent efforts and wishes, no manmade fingerprint has been determined. Their last great hope appears to be that “the warming” has magically vanished into the deep oceans. And they call themselves “scientists”.
+1
My own response got dumped in the wrong part of the thread, so not to steal your thunder, but here it is again:
davidmhoffer December 24, 2014 at 3:31 pm
James Abbott December 24, 2014 at 2:58 pm
What has caused the warming if not CO2 ? Occam’s Razor applies.
What caused the MWP and the LIA? What caused the steady increase in temps from the LIA until CO2 levels started to increase in a meaningful way since about 1920? If CO2 is the simplest answer, why does the period of largest CO2 increase (the last 20 years) not correspond to the largest change in temperatures? You cannot apply Occam’s Razor to this question because CO2 increases fail to explain the behaviour of the system as a whole over time. Occam’s Razor requires that the simplest answer be valid under all conditions, and so CO2 is falsified by Occam’s Razor in this instance.
Close, but no cigar. . You got the mechanism, emission from a higher level of the atmosphere with all the emission from lower down being trapped, but except for the CO2 Q branch (in the center of the 15 um band) the level at which the atmosphere emits to space is well within the troposphere where temperature decreases with altitude. Even at much higher CO2 concentrations emission to space from the troposphere will be considerable.
Eli suspects that you may have neglected decreasing atmospheric density with altitude.
Eli, Decreasing density would just make it that much more difficult to cool the upper atmosphere. You do get an inverted spike with increasing CO2 at 15 microns. That is probably due to CO2 temperature being so low that is has limited degrees of freedom as it nears is triple point. CO2 concentrations are not high enough for it to precipitate out, but that doesn’t mean it radiant properties can change.
In any case, this approach is similar to Kimoto’s which indicates the actual “surface” isn’t like to respond to the full CO2 impact estimates. Some surface where evaporation and convection are less involved could, but the moist atmospheric boundary layer isn’t likely to let the majority of the surface behave like an ideal GHG model.
Thanks, Richard. I will look at that article. But I suspect that Eli is right.
Mike M.
Richard, and Captain D, the spike is the Q branch and in that band, the absorption is so strong that emissions from the troposphere are trapped, and only emission from CO2 in the stratosphere can escape into space. However, the Q branch covers only a small part of the 15 um CO2 spectrum.
The height of the spike identifies the temperature of the level of the stratosphere that the emission is taking place from. You can see this in the Chicago MODTRAN applet. To make things clearer set everything except the CO2 mixing ratio to zero and vary the CO2. In the tropics the Q branch spike emits to space from about 35 km where the temperature is ~245 K.
The thermal structure of the atmosphere is controlled by the lapse rate and the absorption of oxygen and ozone in the UV and does not change much as CO2 concentrations increases. What does change is the width of the CO2 15 um absorption increases (play with MODTRAN). That means that with increasing CO2 a decreasing amount of energy reaches space (or 70 km, but Eli repeats himself).
To maintain thermal equilibrium increasing amounts of energy have to reach space in other regions of the spectrum, and that turns out to be in the so called atmospheric windows, where increased blackbody radiation from warming surface can be generated. Note that in Chicago MODTRAN the temperature of the ground is fixed. Best- Eli
I’ve looked at Richard’s article. It does not seems unreasonable and certainly does not make as basic an error as Eli suggests. But it does seem to be a somewhat crude form of the radiative transfer calculations done in climate models. So I see no reason to trust his result over the well established result.
Mike M.
Eli, what I was referring to was the limit at 245K (-28C) and below. You can 10xCO2 at that temperature and get virtually no change in OLR. That would mean advection pole ward as well as convection upward would be negative feedbacks as they approaches 245K. Ozone and traces of water vapor kick in at the poles to limit minimum temperatures to around 184k which is the Turbopause temperature ~100km.
Captain Dallas, take a look at this from arXiv, it may cover some of your issues. The take home is various ways of making the simple one dimensional model discussed here more realistic by including such things as rotation, heat capacity of the oceans, albedo variation, etc.
Bottom line is that without IR absorbing gases in the atmosphere, the upper limit of the Earth’s surface temperature is 255 K. That is an upper limit.
Taking TSI as 1362 W m^-2, and sigma = 5.67051E-8 W m^-2 K^-4 ; a perfectly conducting isothermal, perfectly spherical black body, has an equilibrium Temperature of 278.37 K
But Earth is not perfectly thermal conducting, nor is it anywhere nearly isothermal, having a surface Temperature extreme range of about 150 deg. C and typically 120 deg. C
Because it is not infinitely thermally conducting, heat cannot propagate instantly to the dark side, to get equal BB radiant emittance all over the entire surface, so the sunlit half of the sphere has to run at higher Temperatures than 273.37 K in order to get rid of all that incident solar energy.
A 255 K spherical isothermal black body would require a TSI of 959.05 W m^-2, or a grey body with a total emissivity of 0.704 , or an albedo of 0.296.
If you remove all the green house molecules from the atmosphere, which includes H2O, you get no clouds, and albedo isn’t nearly 0.296. The moon has an albedo of around 0.118 but it doesn’t have any surface areas with a reflectance as low as 2-3% like Earth’s oceans have for 70 % of its surface area.
So I think Eli is incorrect in saying that 255 K is the upper bound on the effective BB temperature of earth, sans GHMs.
EXPLANATION
The article (and various comments) are correct in that IR absorption by CO2 is essentially saturated, except for slight broadening of the bands. But that is NOT the mechanism by which extra CO2 produces warming.
Each IR photon emitted from the surface is absorbed and emitted (as a separate photon) several times on the upward path to escape to space. Eventually the photon is at sufficient altitude that few CO2 molecules lie between it and space and it likely will escape rather than be absorbed. That height is called the emission height, and varies around the Earth, generally in the upper troposphere, but sometimes the stratosphere. But the RATE at which a CO2 will emit an IR photon depends on the temperature to the fourth power. And the atmosphere gets colder with altitude. (This makes the rate of IR emission very sensitive to temperature.) So more CO2 added to the atmosphere forces the last CO2 emission to space to occur from greater heights. And because it is colder there, the rate of IR loss to space slows down.
When the RATE of heat loss from an object slows down, the object heats up. (Think of donning an overcoat on a cold day. The rate at which you lose heat slows down and you get warmer, until a new equilibrium is reached.) Similarly, as the atmosphere heats, the emission height grows warmer until the rate of IR emission from CO2 counter-balances the incoming solar energy. This produces a new thermal equilibrium, but with the Earth’s surface and atmosphere at a higher temperature.
Is part of your problem that half of the photons are emitted back towards the surface? I means, besides the problems with the equations? That would bring you to 1.2, which is at least closer to normally accepted values.
I’ve had a question relative to this claim. While it makes sense that more CO2 would block outgoing radiation, we also have the situation that more CO2 will increase the number of radiated photons. How do these effects balance out? If it is even then the emission height will not increase.
Outgoing IR photons mostly originate initially from the surface where solar irradiation impinges. A CO2 molecule absorbs a photon, which increases the molecule’s energy, which then may transfer that energy to other molecules (e.g. O2 and N2) or re-emit a photon. The CO2 molecules do not by themselves increase the number of photons. Increased H2O and CO2 do increase the number of IR photons directed back to the surface for re-emission (sort of a closed cycle). This occurs because the more times CO2 or H2O absorb and reemit a photon in the process of upward escape, the more likely some of those will be directed back to the surface. This is a consequence of the outgoing heat (IR) being delayed in the atmosphere before escape. But the energy escaping from the top of the atmosphere (the only way the Earth can lose it, ignoring minor surface retention by e.g. plants) depends upon the solar incoming energy, whatever the number of CO2 or H2O molecules present.
Incoming solar photons have relatively low abundance of IR wavelength, but those are absorbed by CO2 and H2O.
The “issue” with how much warming CO2 can produce lies not in the process I describe, but in feedback factors that increase or decrease the CO2 effect, e.g., does increasing temperature produce more clouds that reflect more incoming solar to space, but also may increase the greenhouse effect of more moisture in the atmosphere.
Actually the rate of emission depends on the Einstein coefficient of the excited state not T^4.
I’m not a physcists and my last physics class was high school.
However my thoughts on the matter are that heat tends to escape. If there is a way for heat to get out it will.
Equation 1 in the original post, at best, makes no sense as a model of a dynamic process and at worst is just flat out wrong. It looks like the “constant” on the right hand side of the equation is supposed to be the incoming solar radiation (which is presumed to not change). That part is fine. But if the right hand side is heat or energy, the left hand side has to have the same units. Yet, as far as I can tell, it has units of temperature [if the “a” is simply a proportion of “energy over energy” that would make (1-a) dimensionless since the “1” has to be of the same dimension as “a” to carry out a subtraction operation]. Conversely, if the constant on the right hand side is expressed in Kelvin, then the equation makes no sense because it permits no changes in temperature, yet is used to calculate the value of “a” given a presumed change in temperature.
I THINK the original poster begins with the assumption that the net outgoing radiation has to equal the net incoming radiation (presumed constant), sets the net outgoing radiation to the radiation emitted from the surface (proportional to T^4) minus the radiation reflected back by the atmosphere, but then illogically expresses the reflected energy as a percentage of the energy emitted from the surface. The problem, as I see it, is that “a” is not a variable that directly changes as a function of surface temperature (the specific temperature of the radiating gas molecule, maybe, but not surface temperature). You can arbitrarily express is as a percentage of surface temperature, just as you can arbitrarily set it as as a percentage of the volume of tea I drink during the day, but neither has any physical meaning. Stated differently, when you multiply T^4 through the (1-a) you don’t get anything that physically makes sense for the variable aT^4.It doesn’t represent anything except for a contrived, arbitrary expression of retained radiation as a fraction of surface radiation. Thus. you can’t just plug in a couple temperatures into equation 1 and solve for “a”.
Your comment has caused me to study the Stefan-Boltzmann Law finally once and for all. The equation (1) appears to me to be formed correctly, and “a” is essentially the buffer or difference or retained heat compared to a black body without an atmosphere, more or less.
I have not read the referenced document to Barrett yet so can’t comment on the rest of this authors calculations.
I am more interested in writing computer climate models, and have spent the last few years studying the Math and related technologies.
That is complete nonsense. Infrared absorption by CO2 will never be saturated in the Earth’s atmosphere. Use any HITRAN model you want (I wrote my own, just to be sure), CO2 must be more than 10 times the total size of the Earth’s atmosphere before it is saturated. To be clear – >10,000,000 ppm – a number not possible by simply burning fossil fuels. (There simply is not enough oxygen to produce that much CO2.)
If some claim is based on the saturation of CO2, then the claim is wrong.
That’s nonsense . If CO2 is not effectively , eg , .95 saturated within a couple of hundred meters of the surface , then it is inconsequential as a “greenhouse gas” .
Neat knotion that a gas can be 10 million parts per million before being “saturated” .
And , interestingly , I’ve seen figures that the original atmosphere was on the order of 300,000ppm ( 30% ) CO2 before green life and shell forming creatures exploded releasing all the O2 we animals require , depositing the strata of fossil fuels and limestone , and exhausting the CO2 down to levels which just bounce along the minimum required for green life .
There are 2 different definitions of “saturated” – one is the effect at a single wavelength. For a significant part of the CO2 spectrum, the most of the available energy is absorbed within a few hundred meters. As a result, CO2 is an important greenhouse gas.
The other definition considers the entire spectrum. When that is done, CO2 is not saturated. This is because there are some frequencies that are not currently saturated. As a result, adding more CO2 will saturate some frequencies that are currently absorbing only about 50% of the available energy, and other frequencies that are currently absorbing next to nothing will begin to absorb a bit more. This part of the absorption spectrum is referred to as the “wings” of the absorption bands. For the current wings to become saturated, the amount of CO2 in the atmosphere must be more than 10 times the total amount of gas (oxygen and nitrogen) currently in the atmosphere – thus >10,000,000 ppm ! This is pretty settled physics, not controversial.
Limestone is an interesting substance, for every 2 molecules of CO2 removed from the atmosphere, one molecule on oxygen (O2) is required. This oxygen could come from either the atmosphere or the oceans, but there is no way that I know of that the creation of limestone can increase the amount of oxygen in the atmosphere.
There are a number of comments that suggest that half the photons re-radiated by CO2 molecuels go back down to the surface.
But is that not, as a matter of geometry, an exaggeration?
I have not looked at the geometry of the sherical shape that makes up Earth’s atmosphere, but my immediate visualisation is that some photons reradiated will be radiated sideways, or at a grazing angle of say somewhat less than 5deg to the surface. Such photons that are radiated at higher altidues surely will never hit the surface.
Is not the correct position that somewhat less than half of re-radiated photons find their way upwards to TOA and thence to space, somewhat less than half find their way top the surface, and some small percentage remain forever locked in the atmosphere neither making it to space nor to the surface.
No doubt the effect is relatively small, but even small effects become significant when one is looking at a balanced or imbalanced budget.
I have also always been bothered by the ignoring of 3 dimensional geometry in “climate science”. The ignoring of the globe as a rotating sphere really gets my goat.
On top of that, I think that many explain the “CO2 absorbs a proton” thing without mentioning that the molecule will most likely bump into another non-CO2 molecule (nitrogen or oxygen most likely) before it can radiate the energy. BUT, even if it does radiate said photon, why will the photon go all the way to the surface or all the way into space without hitting another CO2 molecule?? Would a photon somehow “know” that it is not supposed to be absorbed again? How would that work?
BUT, even if it does radiate said photon, why will the photon go all the way to the surface or all the way into space without hitting another CO2 molecule?? Would a photon somehow “know” that it is not supposed to be absorbed again? How would that work?
It doesn’t “know” and if it impacts another CO2 molecules while going up or down, it does get absorbed again. That’s the whole point. That it must be absorbed and re-emitted many many times before it gets high enough to see a free path to space.
@davidmhoffer
“…That it must be absorbed and re-emitted many many times …”
Since the CO2 molecule is much more likely to bump into a nitrogen or oxygen molecule before it can radiate the photon, and since it has many chances to do so as you point out — then the energy must go to the non-CO2 molecules almost immediately and so convection dominates the whole process in the lower atmosphere (troposphere). So, radiation does not inhibit convection, it enhances it all else being equal.
This does not look like the “team’s greenhouse effect” at all. It looks like the model that the physicist Maxwell described so very long ago. Conduction and convection drives the weather machine and CO2 does very little on net if anything.
markstoval wrote: ” the ignoring of 3 dimensional geometry in “climate science”. The ignoring of the globe as a rotating sphere really gets my goat”. What gets my goat is know-nothings like markstoval spouting this sort of ignorant nonsense.
Mike M.
But is that not, as a matter of geometry, an exaggeration?
The 1/2 up and 1/2 down is a simplification in order to explain the basic concept. Obviously in the real application, some portion are emitted at all angles, and depending on how far they travel, an angle “slightly down” or even “sideways” could become “up” at the end if the path is long enough.
@ur momisugly davidmhoffer
There seams to be a lot of “simplification” in climate “science”. A whole lot of “simplification”. Over simplification in fact.
EXPLANATION
On some of the comments above: Photon emission by CO2 (or H2O) is random, up, down, or sideways. It is a “statistical walk” for a photon to eventually escape to space. Most emissions are within the troposphere where the Earth’s surface appears almost flat. But by comments expressed above, there is a preference for net upward motion. When a CO2 (or H2O) molecule absorbs an IR photon and gains energy, that energy can be distributed several ways. It can increase energy of the molecular bonds (think bond motion, of which there are several possibilities, depending on the molecule); it can collide with another molecule (likely N2 or O2) and transfer some of that energy; it can emit an IR photon and lose energy. If #s 1 or 2 occur, the molecule may not have sufficient energy to emit a photon (photon energies are quantized; i.e. they can only occur in specific energy levels). But, another molecule can strike the molecule that has lost energy and give it sufficient energy to now emit an IR photon. In this way energy of an absorbed IR photon is distributed through the atmosphere and delayed in reaching space.
By the overcoat analogy, slowing heat loss causes the planet to warm.
markstoval December 25, 2014 at 5:55 am
@ur momisugly davidmhoffer
There seams to be a lot of “simplification” in climate “science”. A whole lot of “simplification”. Over simplification in fact.
You asked a question and I answered it. If you want the “full” explanation, you’re not going to get it in a blog post. You’ll have to learn some calculus and read some text book, big fat thick ones. If you want something in between, start with these:
http://wattsupwiththat.com/2011/05/07/visualizing-the-greenhouse-effect-light-and-heat/
http://wattsupwiththat.com/2011/03/29/visualizing-the-greenhouse-effect-molecules-and-photons/
http://wattsupwiththat.com/2011/02/28/visualizing-the-greenhouse-effect-atmospheric-windows/
@davidmhoffer
“You’ll have to learn some calculus and read some text book”
My, my, Does that mean I have to repay the salary I got for teaching calculus those years? And what big, bad, scary textbook will treat the 3-d, dynamic, chaotic system fully? Hmmm?
PS: I suspect the grammar error was just a typo and not karma. (no, really I do)
@Donald Beal
“By the overcoat analogy, slowing heat loss causes the planet to warm.”
Oh my god. You typed that swill on Christmas day for god’s sake.
An overcoat can cool people in the desert by keeping the sun off of them. Ever notice how the desert people cover up with their clothes?
An overcoat will not help warm a dead man whose body does not give off its own heat — just like the earth’s heat does not come from inside. (there is a big ball of fire in the sky ya know)
What we have here is more over simplification that is evidence of not a thing. But thanks for proving my point about too much simplification.
Mark Stoval;
PS: I suspect the grammar error was just a typo and not karma. (no, really I do)
Then why draw attention to it?
I agreed with you on photons not knowing if they had already been absorbed or not, I agreed with you on the geometry issue you raised, I pointed out that the purpose was to illustrate a point, and when you complained about that I pointed you to some pretty good articles on the subject and suggested that the level of detail you were insisting on could not be dealt with in a blog post. Yet still you complain. Did you even read the articles I suggested?
just like the earth’s heat does not come from inside. (there is a big ball of fire in the sky ya know)
Well actually, for the purposes of discussion of the greenhouse effect, the heat does come from the “inside”. It goes through the atmosphere as SW from the Sun from outside the atmosphere, gets absorbed by the Earth, and re-emitted from inside the atmosphere. But if you’d bothered to read the articles I pointed you at, you’d know that.
Some people are trying to help you, and BTW, we’re skeptics, not warmists nor alarmists. So before you start p*ssing on us for trying to help answer your questions, consider that you could put your math skills to work and consider that the physics we’re trying to explain in this rather limited forum might well be genuine.
Well We actually have experimental; well observational proof, that at least half will head downwards towards the surface.
At sunset, when the lower limb of the sun touches the visual horizon, the sun is already completely below the geometric horizon, due to atmospheric refraction. So a photon emitted perpendicular to the local earth radius, will actually refract downwards, by a bit more than one half of a degree.
Consequently, only the upwards 179 degree full cone angle, will head to space, and the downward 181 degree full cone angle will head down towards the surface.
But the upward escape direction is still favored, because in that direction lies lower density, and lower temperature, and both of those lead to less broadening of the GHG absorption lines, so an ever narrowing bandwidth can get reabsorbed, heading up.
But heading down, leads to ever broadening spectral absorption, and each reabsorption results in another up / down split, so less radiation would reach the ground, compared to the fraction that escapes to space.
And it is the molecular kinetic energy (velocity) that gets traded between GHG and non GHG molecules in collisions. Those collisions may cause termination of the GHG photon absorption excited state, but the emitted photon must be of the same or nearly the same frequency, as the absorbed one. It is after all a molecular resonance phenomenon.
I agree with the the point that you make regarding the atmosphere acting like a lens and the consequent dispersion of vissible light, but since the refracted angle varies with wavelength, is the effect of that slightly less as you go into the IR waveband?
The more material point made is that regarding loweer density and lower temperatures favouring an upward flow.
Well Richard, the original reticence on your part, to accept a 50:50 split up / down, was based on not accepting a planar thin atmosphere model, which would imply a 50:50 split, as the atmospherically emitted photons are necessarily isotropic in original angular distribution. On that issue, a renowned Nobel Prize Physicist, once told me (over a beer in a friend’s garden) that the no matter how small a region on an idealized spherical earth you choose, the curvature is exactly the same.
So the reality of the curvature of an iso-density lamina of the atmosphere, has to be recognized. It is a fairly standard problem in graded refractive index propagation of EM waves or optical rays in the geometrical optics simplification.
In the case of air, the refractive index is quite small, but it is not equal to one, and it is wavelength dependent. However, in the LWIR region, the index is practically constant over the whole BB envelope of the earth LWIR emission spectrum, and it is also density dependent.
Since the atmospheric gases are IR inactive (excluding GHGs), at leas as far as atomic or molecular resonance lines, there should be no anomalous dispersion edges, anywhere in the LWIR spectrum of interest to GHG climate issues. So the index will decline at longer wavelengths, but negligibly so. The dispersion is always steeper at shorter wavelengths, until you cross a resonance edge, where you get an anomalous dispersion .
So even though the effect is small, it isn’t zero, and optical rays will refract away from the zenith, when travelling upwards.
The effect of atmospheric refraction , causes a significant change in the visible region in the apparent angular velocity of distant stars. Near the zenith, the apparent angular velocity of a star is less than the actual angular velocity of the earth, since the star is displaced towards the zenith.
It seems to me, that the sidereal day is something like 86,164.09 seconds. I don’t know why that number comes to mind, but it does. As result, of the refraction, a telescope clock drive has to run slower than sidereal by something like 12-16 seconds per day, to track a star across the zenith.
It would be a smaller discrepancy for the LWIR region.
In any case, geometrically, more photons start down, than up, but the line broadening gradient favors the escape route, because of the multiple absorptions.
GHGs are such a small part of the atmosphere, they have virtually no effect on the atmospheric refractive index. Well water might be enough to show an effect, but CO2 won’t affect the index measurably.
I actually built a quartz crystal controlled clock drive for a small telescope, that used a special GT cut quartz crystal, running at something like 492 kHz (high for a GT) that divided by 2^13 and produced roughly 60 Herz two phase square waves to drive a 1200 RPM 6 pole synchronous motor (1/2 inch diameter: aka size 5). A worm reduction followed by a hypoid spiral reduction produced a one rev per siderial day plus about 26 seconds, for the refraction. That was capable of tracking a star for about six hours across the zenith, to less than one arc second deviation.
I think the crystal frequency was 492.718 kHz
Well, considering how long it’s taken for the average temperature anomaly to hit 0.600 maybe you’re onto something
http://www.wunderground.com/blog/joshuah/comment.html?entrynum=4
Steven Mosher – this is not the British Daily Mail or The Guardian where such comments are regularly on display – as if anyone could give a **** regarding someone’s unsupported opinion.
I got roughly the same results by accepting what I read that a doubling of CO2 would result in a 3.7 increase in wattage flux per square meter, and plugging in the figures.
The Stefan-
Boltzmann equation for a blackbody goes
T(degrees Kelvin) = S(constant)*(watts/square meter)^0.25. Our
first step is to find that S constant.
Doing a google search, I find 1000 K implies a blackbody flux of 56790
watts/square meter.
1000K = S* (56790 watts/square meter)^ 0.25. Click on your
calculator and use the scientific view. Plug in 56790
X^Y
0.25
=
and you get 15.43718 Divide 1000K by 15.43718 and you get S =
64.77867
We now know
T(kelvin) = 64.77867 ( watts/square meter)^0.25.
For a blackbody, climate sensitivity would be
1/4 dT/ dS
For a surface temperature of 288 K, this amounts to
(1/4)( 288K/342 watts) = 0.21 K/watt
or an increase of about 0.777 K for a doubling.
Of course, that additional wattage would not be added to the rays direct from the sun, bu from Trenberth’s figures, to the 390 watts the earth’s surface gets.
1/4(288K/390 wats) gives a sensitivity of 0.185 K per watt increase.
Also, from Trenberth’s figures, theres an additional 100 watts going into the latent heat of vaporizaion of water and into convection. Using those figures,
1/4(288K/490 watts) gives a sensitivity of only 0.147 K per watt increase. Of course
the earth is a graybody, not a blackbody.
Assuming an emissivity of 0.8, If we divide that
0.147 K./watt by 0.8 emissivity, we get the same 0.7 K incrrase for 3.8 additional watts that Saburu Nonogaki got.
Alan, I hate to tell you this but the Trenberth et al. series of Earth energy budgets all have a number of errors and overly optimistic assumptions. One of the worst is their “fixed” atmospheric window value of 40 Wm-2, The actual surface window is closer to 20 Wm-2 and the 40 Wm-2 would be more accurate for a surface above the atmospheric boundary layer.
http://judithcurry.com/2012/11/05/uncertainty-in-observations-of-the-earths-energy-balance/
That imposes a bit of a limit on CO2 impact at the real “surface” due to water vapor creating an “effective” saturation. There is no real saturation, but it does throw early calculations off quite a bit.
As Mosher is a graduate English major I assume he is indicating a problem with the grammatical construction of the article, I highly doubt he was referring to the science.
His follow up comment, as well, indicates we would likely not be able to understand the language in his explanation, either.
Mark
EXPLANATION
Alan McIntire,
I don’t follow exactly what you did above, but HERE IS A CALCULATION FOR THE EARTH’S ENERGY BALANCE using temperature units.
The rate of energy radiated by an object (e.g. the Earth) equals q*T^4, where T is temperature and q is the Stefan-Boltzman constant = 5.67 * 10^-8 (units W/m^2 per K^-4)
Solar radiation heats the Earth as S*(1-a)/4, where S is the solar constant (~1365 W/m^2) and a is Earth’s albedo, variable but around 0.3. We divide by 4 to convert from the plane geometry of the Sun impinging on the Earth to the spherical Earth’s surface area (correcting for day/night and the angle of the Sun’s rays striking Earth’ surface).
Because the energy the Earth receives is in equilibrium with the energy lost by radiation, we set these two relations equal to each other.
q*T^4 = S*(1-a)/4
If we assume the Earth acted as a black body and had no atmosphere or albedo (a=0) and solve for T, this would give the Earth’s effective black-body temperature. (This is an artificial temperature, because the Earth has an atmosphere, an albedo, and surface materials that do not radiate like a black body, but at a lower emissivity. More on that below.)
Solving this equation for T gives 278 K.
If we assume the Earth has an atmosphere with a=0.3, but otherwise behaves like a black-body, solving for T gives 255 K. This assumption is akin the actual Earth condition, in that the Earth has an atmosphere and does reflect about 30% of incoming solar radiation.
The actual average (global) temperature of Earth’s surface is about 288 K. Comparing this temperature to the two “black-body” analog temperatures above indicates that a greenhouse effect has raised the global temperature by either 288-255 =33 K (for a=0.3), or by 278-288 = 10 K (for a=0).
The concept of emissivity of a body is how effectively a body radiates heat compared to a black-body, defined as having emissivity (e) equal 1.0. The average of Earth’s surface has an emissivity of ~0.96.
Considering that the Earth does have an albedo (a=0.3), but surface materials that radiate only 96% as efficiently (e=0.96) as a black body, that Earth surface would have to rise in temperature above that of a black-body by a modest amount (4%*255K =10K), until energy equilibrium was reached.
The difference between the Earth’s measured surface temperature (~288K) and Earth’s black-body temperature (however one wishes to define it above –255K, 265K, or 278K), is the greenhouse effect. The most reasonable greenhouse temperature rise is probably 288-265=23C, as that calculation represents the actual Earth albedo and the emissivity of actual Earth surface materials. But under all reasonable scenarios, the actual temperature is higher than it would be without a greenhouse effect produced in the atmosphere.
However, you will note the sensitivity such a calculation has on the value of albedo, a. A one percent change in a is worth some 3.4 watts in TOP solar insolation, equivalent to about a degree-C.
Exactly what produces that greenhouse effect is another issue.
The ocean
I’m aware of your figures. What you would be computing is the temperature increase of the sun if the sun’s wattige iincreased from 1368 per square meter to 1368 + 4(3.7/.7) watts per square meter
We take 1/4 of that, because that’s the average wattage spread over a circle pi*r^2, while the rotating spherical earth has a surface of 4*pi*r^2.. So of the additional 5.2857 w atts from the sun, 30% is reflected away leaving 3.7 watts to hit earth. Additional wattage from the sun operates somewhat differently than
additional wattage due to increased greenhouse effect.
See
, http://jennifermarohasy.com/2009/03/radical-new-hypothesis-on-the-effect-of-greenhouse-gases/
Saburu Nonogaki was questioning the 3.7 additional wattage per square meter flux with a doubling of CO2. My calculation was accepting that 3.7 watt figurre and plugging in the numbers. They were in the same ballpark as Nonogaki’s figures.
Does atmospheric friction from a rotating earth add heat to the system?
Tidal friction (from the Moon) would add much more. I don’t know the values, but would expect them to be much, much smaller than solar heating, just as volcanic heating is.
An indication of the atmospheric temperature vs CO2 concentration sensitivity is available in the empirical data from the HadCrut4 global temperature listing and the Mauna Loa CO2 concentration listing from the Scripps Institute.
Least squares regression for the period November 1958 to November 1963 gave a rate of temperature increase of 1.1 degrees per century (probability of zero rate being 19%) for an increase in CO2 concentration at a rate of 69 ppm per century (probability of zero rate being 0.02%). This may be compared with least squares regression for the period October 2009 to October 2014 which gave a rate of temperature increase of 0.7 degrees per century (probability of zero rate being 43%) for an increase in CO2 concentration at a rate of 222 ppm per century (probability of zero rate being practically zero). That is, a 325% increase in the rate of CO2 increase apparently has caused a fall in the rate of global warming.
Perhaps more significant was the summary of 36 years of satellite temperature measurement “Global Temperature Report: November 2014” by Dr John Christy on WUWT for December 03, 2014. It stated that “The fastest warming has been over the Arctic Ocean and the Arctic portions of the Atlantic and Pacific oceans. Those areas have warmed at the rate of 0.49 C per decade, or more than 1.76 C (about 3.17 degrees Fahrenheit) in 36 years. The fastest warming spot is in Baffin Bay, where temperatures have risen 0.82 C per decade since 1978.” At Alert Station just north of Baffin Bay, the rate of increase of CO2 concentration has been + 16.7 ppm per decade
for the period July 1975 to December 2013.
Further, “By comparison, the oceans surrounding the Antarctic are cooling at the rate of 0.02 C per decade,…. The fastest cooling area is in East Antarctica near Dome C, where temperatures have been dropping at the rate of 0.50 C per decade.” However the rate of increase of CO2 at the NOAA South Pole station has been + 16.7 ppm per decade, identical to that over the North Polar region.
Clearly changes in the Earth’s surface temperature are unrelated to change in atmospheric CO2 concentration.
Just as the temple priests of old offered to save the populous from plague and pestilence in return for prestige, wealth and privilege, the UN is now offering to save us from catastrophic climate change cause by the minute amount of man-made CO2 in the atmosphere in return for a Global Climate Fund of $10 billion and control over our national sovereignty.
The absorption spectrum of CO2 has many fine features, and even the MODTRAN model does not have enough resolution to model these accurately. Dr. Roy Spencer, on the skeptic side of the climate change debate, does not dispute the IPCC figure of a doubling of CO2 causing a 1.1 degree C doubling if there is no net negative or positive feedback.
See my comment above on 12-14 at 5:06 PM
davidmhoffer,
Nice work on this thread. I only say this because you caught some flak for trying to explain this; seems like you deserved to hear some gratitude too. I thought about trying to explain too but I wasn’t confident enough I could present it properly without stepping on my d/ck halfway through, so I didn’t bother.
anyways. Merry Xmas.
Tx Mark, appreciated.
Being a simple soul I’ve used Professor Akasofu’s diagram to work out my estimate of the maximum climate sensitivity.
The atmospheric CO2 concentration started to rise from ~280 ppm around 1880 according to Law Dome ice cores and is expected to double around 2060 according to the IPCC assuming business as usual.
The observed warming due to whatever cause since then would include accompanying feedbacks.
Projecting the observed global temperature linear trend from around 1880 to 2060 produces a temperature rise of ~1.2C which, empirically, would be the maximum sensitivity assuming all the observed warming was due to CO2.
http://wattsupwiththat.files.wordpress.com/2009/03/akasofu_ipcc.jpg
Please people, would you accept this derivation from the AGW-crowd? It displays none of the complexity we know to exist in the climate system. Why would you even publish this?
I guess because some warmists, and some luke warmers consider that it is possible to assess climate sensitivity through empirical calculation.
It is a moot point as to whether there is such a thing as climate sensitivty to CO2 as Bevan Dockery (at December 25, 2014 at 5:47 pm) illustrates. to date, there is no empirical observational data that passess scientific scrutiny showing any first order correlation between CO2 and temperature. As matters presently stand, even with our best measuring devices, and within their error bounds, we are unable to extract the signal of CO2 (if any at all) from the noise of natural varition.
This leads us to the point. Climate sensitivity may well be a maningless concept but if it has validity, it can only be determined by real world empirical observational data. And we will never be able to answer the Climate Sensitivity to CO2 issue, until such time as we know absolutely everything there is to know and understand about natural variation. precisely what it comprises of, AND the upper and lower bounds of the forcings of each and every constituent component that makes up natural variation.
until we have that knowledge and information, everything is conjecture and farce. .
Perhaps in my above post, I should have made it clear that I am talking about CO2 driving temperature, as opposed to a rise in atmospheric CO2 levels being a response to an antecedent temperature rise.
That’s not right.
Most of us would say that the average temperature is calculated by adding the temperature of each square mile of the Earth’s surface and dividing by the number of square miles.
The Stefan–Boltzmann law calculates the total energy radiated per unit surface area of a black body.
Let’s take two possible cases:
The energy radiated by a planet with a uniform temperature
The energy radiated by a planet where the temperature is different on different parts of the planet
We set the ‘average’ temperature of the two hypothetical planets to be the same.
We calculate the radiated energy in both cases for every square mile and sum that to get the total radiated energy.
The planet with variable temperatures will radiate quite a bit more energy than the one with a constant temperature. This is because the radiated energy is proportional to the fourth power of the temperature.
Here’s a numerical example:
Planet A and Planet B have the same average temperature
Both planets have an area of two square miles. Both orbit the same sun but one is closer to the sun and receives more radiation
The inhabitants of both planets define their thermal units such that δ = 1
Conditions on Planet A are such that the temperature is absolutely uniform = 300K
On Planet B the sun side is 400K and the dark side is 200K. The average is, of course, 300K
Calculating dark and sun side radiation for Planet A
dark side radiation = 1 mi2 × 3004
sun side radiation = 1 mi2 × 3004
Total radiation = 81 x 108 units
Calculating dark and sun side radiation for Planet B
dark side radiation = 1 mi2 × 2004
sun side radiation = 1 mi2 × 4004
Total radiation = 136 x 108 units
So, Planet B is closer to its sun because, to radiate the energy it does, it must be receiving more radiation.
It is also possible to work the equations to calculate the average temperatures of two planets, Planet C and Planet D which are the same distance from their shared sun.
Based on the above calculations, we see that the planet that distributes heat over its surface the best will have the highest average temperature.
Since the Earth and Moon are the same distance from the sun, and since the Moon has much more dramatic temperature swings than the Earth, we would expect the Earth to have a higher average temperature (all other things being equal; which they aren’t).
A good part of the ‘greenhouse effect’ can be explained by the fact that the Earth has heat distribution mechanisms that the Moon doesn’t. The exact calculation is non-trivial because, although the Moon is something like a well-behaved black body radiator, the Earth’s radiation spectrum varies significantly from an ideal black body. ie. The greenhouse effect does matter; I just think it isn’t the whole story.
AARGH! None of my html tags worked. In particular, the superscripts vanished. Here’s a corrected version. In this case 300^4 should be read 300 to the fourth power.
That’s not right.
Most of us would say that the average temperature is calculated by adding the temperature of each square mile of the Earth’s surface and dividing by the number of square miles.
The Stefan–Boltzmann law calculates the total energy radiated per unit surface area of a black body.
Let’s take two possible cases:
1 – The energy radiated by a planet with a uniform temperature
2 – The energy radiated by a planet where the temperature is different on different parts of the planet
We set the ‘average’ temperature of the two hypothetical planets to be the same.
We calculate the radiated energy in both cases for every square mile and sum that to get the total radiated energy.
The planet with variable temperatures will radiate quite a bit more energy than the one with a constant temperature. This is because the radiated energy is proportional to the fourth power of the temperature.
Here’s a numerical example:
Calculating dark and sun side radiation for Planet A
Calculating dark and sun side radiation for Planet B
So, Planet B is closer to its sun because, to radiate the energy it does, it must be receiving more radiation. To get it to radiate the same energy as Planet A, we would have to move it farther from its sun. As a result its average temperature would go down.
It is also possible to work the equations to calculate the average temperatures of two planets, Planet C and Planet D which are the same distance from their shared sun.
Based on the above calculations, we see that the planet that distributes heat over its surface the best will have the highest average temperature.
Since the Earth and Moon are the same distance from the sun, and since the Moon has much more dramatic temperature swings than the Earth, we would expect the Earth to have a higher average temperature (all other things being equal; which they aren’t).
A good part of the ‘greenhouse effect’ can be explained by the fact that the Earth has heat distribution mechanisms that the Moon doesn’t. The exact calculation is non-trivial because, although the Moon is something like a well-behaved black body radiator, the Earth’s radiation spectrum varies significantly from an ideal black body. ie. The greenhouse effect does matter; I just think it isn’t the whole story.
commieBob, December 26, 2014 at 7:46 am:
“A good part of the ‘greenhouse effect’ can be explained by the fact that the Earth has heat distribution mechanisms that the Moon doesn’t.”
Not really. Certainly, part of the ACTUAL atmospheric effect on the planetary mean surface temp does indeed arise from this fact. But it doesn’t matter AT ALL to the ‘radiative greenhouse effect’ (rGHE) as theoretically defined. It, after all, starts out assuming that the global surface of the Earth comes with ONE single, perfectly smoothed-out temperature across its entire surface, across the entire diurnal and annual cycles: 288K. This is higher by 33K than even a completely isothermal black body surface isotropically emitting a radiative flux of 240 W/m^2 into a vacuum at 0 K could ever reach: 255K.
“The exact calculation is non-trivial because, although the Moon is something like a well-behaved black body radiator, the Earth’s radiation spectrum varies significantly from an ideal black body. ie. The greenhouse effect does matter; I just think it isn’t the whole story.”
The surface of the Moon indeed acts ‘something like a well-behaved black body radiator.’ Simply because it sheds its entire heat loss directly into a (near) vacuum by way of radiation. It is a ‘pure emitter’. Its ‘Q_in Q_out’ setting is a purely radiative one. Hence, the Stefan-Boltzmann equation is directly applicable. Not so at all for the surface of the Earth. It behaves nothing like a black body radiator. Simply because it does NOT shed its entire heat loss directly into a vacuum by way of radiation. Simply because it ISN’T a ‘pure emitter’. Simply because its ‘Q_in Q_out’ setting ISN’T a purely radiative one.
Kristian:
I have tried to demonstrate that using an average temperature is not vaid. The math is simple. Show me why my calculation is wrong.
The author attempts to predict what will happen in the future. There’s no reason to believe his predictions will be any better than prior long term climate predictions, so he should either be ignored, or ridiculed for pretending his climate astrology is real science.
.
There is no scientific proof the last +100 ppmv CO2 increase caused any warming, and the long periods with no warming since 1940 (1940 to 1976, and 1998 through 2014) strongly suggest CO2 is a minor variable overwhelmed by other causes of climate change … such as the sun, volcanoes, tilt of the Earth’s axis, water vapor, methane, clouds, ocean cycles, plate tectonics, shifting ocean currents, albedo (Earth’s changing reflective properties), atmospheric dust, atmospheric circulation, cosmic rays, particulates like carbon soot and volcanic dust, forests and grasslands, urbanization and other land use changes.
.
Climate change is governed by hundreds of factors, and CO2 is just one of many. It appears to be a minor one.
.
Assuming you believe it, the ‘greenhouse theory’ itself would support the claim that the next +100 ppmv increase of CO2 will have significantly less of a warming effect than the prior +100 increase of CO2.
.
If one jumps to the conclusion that the prior +100 ppmv of CO2 caused 100% of the warming measured since the 1800s (and assume the measurements were 100% accurate), it is completely logical to want more CO2 in the air, and more warming.
.
CO2 greens the Earth and reduces green plant water requirements while the plants grow faster.
It’s about time for the benefits of more CO2 to be publicized, beyond greenhouse owners.
.
People love a little more warmth, and anecdotal evidence from past centuries clearly shows colder centuries were hated. Consider how often people today vacation in, and retire to, warmer climates!
.
Increasing CO2 another +100 ppmv, from 400 to 500 ppmv, is like adding a fifth opaque blind over a window that already had four blinds covering it. Will the fifth blind block more sunlight than four? Maybe, but who cares — the room was already dark!
.
I favor more CO2 in the air and more warming.
.
The prior +100 ppmv CO2 increase was accompanied by the healthiest and most prosperous period on Earth so far. Who wouldn’t want more of those good times?
.
I oppose air, water and soil pollution in Asia, especially China … but who cares about real pollution anymore?
Richard Greene said:
There is no scientific proof the last +100 ppmv CO2 increase caused any warming, and the long periods with no warming since 1940 (1940 to 1976, and 1998 through 2014) strongly suggest CO2 is a minor variable overwhelmed by other causes of climate change
This is a good point, often stated but also often overlooked.
Many calculations of ECS start with:
“Assume all observed warming is caused by increased atmospheric CO2.”
To which the appropriate response is “nonsense – it obviously is not.”
Then there is the observation that CO2 lags temperature at all measured time scales. So the CAGW hypo is falsified since the future cannot cause the past. See http://wattsupwiththat.com/2014/08/02/introducing-the-wuwt-co2-reference-page/#comment-1703549
True Story. OT, but kindly bear with me Moderator, concerning a very strange event that happened ten years ago today.
My girlfriend Vicky and I were walking on the pebble beach at Sechelt, BC when an unusual question popped into my head.
I asked Vicky: “What would you do if the sea suddenly retreated and left all the little fishes flapping around on the tidal flats?”
Being an animal lover, Vicky said she would run around putting the fish into the remaining shallow pools of water.
I explained that this sea retreat would be immediately followed by a tsunami, and the best move is to run for high ground – the little fishes would be fine, but the people on the beach, not so much.
That evening we joined her parents to watch TV, and heard the first news of the great SE Asia tsunami that killed 250,000 people that day. Pure coincidence? A perturbation in the Force? I have no idea. Vicky just stared at me.
Anyway, I also wanted to tell you that in 2002 I (we) predicted global cooling by 2020-2030… … and our predictive track record is very good. So buy that Honda generator and bundle up. It’s going to get colder out there.
Happy Holidays to all, Allan
We may not yet know what is in control of the World’s climate but we have definitely done enough work to show that it is not CO2.