by Judith Curry
By Judith Curry
Here is another attempt at trying to untangle the Skydragons’ misunderstanding about the greenhouse effect and the planetary energy balance.
To clarify the planetary energy balance equation and its (mis) application to interpreting the greenhouse effect, I am posting section 14.3 [planetary energy balance] from my text Thermodynamics of Atmospheres and Oceans. If you have been following the Postma thread, you should be familiar with the starting point in this section.
The planetary energy balance equation has its greatest utility in the context of comparative planetology. It is not needed to prove the existence of the greenhouse effect, although it is conceptually useful in explaining and understanding the greenhouse effect.
With regards to the planetary energy balance equation 12.1:
The temperature Te is not necessarily the actual surface or atmospheric temperature of the planet; it is simply the equivalent blackbody emission temperature a planet requires to balance the solar radiation that it absorbs. Using a value of ap = 0.31, we obtain from (12.1c) a value of Te = 254 K. Note that this temperature is much less than the observed global mean surface temperature T0= 288 K. The difference between Te and T0 arises from the emission of thermal radiation by atmospheric gases and clouds at temperatures colder than T0.
The ratio of Te to T0 provides an indication of the magnitude of the infrared optical depth, which is referred to as n. n includes contributions from both clouds and gases.
So far nothing new. In section 14.3.2 I introduce the concept of planetary time scales, which I think gets to the heart of the problem that Postma has with equation 12.1.
If radiative transfer is the only process occurring in a planetary atmosphere, the surface temperatures of the planets would be determined solely by the net radiation at the top of the atmosphere. Thus, the equatorial regions would be warmest and the poles would be extremely cold. Whereas this is the case on Mars and to a lesser extent on Earth, other planets such as Venus and all of the Jovian planets have little or no equator-to-pole temperature gradients at the surface or deep in their interiors.
Simple arguments allow us to understand why there are differences in horizontal temperature gradients among the planets. There are two fundamental time scales that determine how a planetary atmosphere transfers heat. The radiative timescale, trad, is the time it would take for an atmosphere above some pressure level p0 to reduce its temperature by 1/e of its initial value via radiative cooling if solar radiation were turned off. The dynamic timescale, tdyn, is the time required to move a parcel over a characteristic distance in the atmosphere and, in so doing, transport heat from one location to another.
Introducing a variable e = tdyn / trad . There are several different regimes for e:
(i) If e >> 1, the dynamic time scale is much greater than the radiative time scale, and hence radiative processes dominate. This regime is characteristic of Mars. Consequently, on a planet with e >> 1, the equator-to-pole temperature gradient is very large, in response the latitudinal variations of solar radiation. Also, as the radiative cooling of the atmospheric parcel is so efficient, a very large diurnal variation of temperature is expected.
(ii) If e << 1, the dynamical transports of heat dominate over radiative cooling. This regime, characteristic of Venus, Jupiter, and Saturn. Thus, for e << 1 a very small or negligible equator-to-pole temperature difference is expected. For similar reasons, the diurnal variation of temperature on such a planet would be negligibly small.
(iii) For e ~ 1, there is parity between the two time scales. Such a situation occurs if the mass of the atmosphere is moderate and the velocities on the planet are relatively weak, which is the case for Earth. On such a planet, one would expect a pole-to-equator temperature difference but one where the temperature of a parcel at a particular latitude is not in radiative equilibrium with the net radiative fluxes at the top of the atmosphere. Furthermore, a moderate diurnal temperature is expected.
In this context, equation 12.1 provides a good representation for Venus, with little diurnal variation and pole-to-equator temperature gradient (Jupiter and Saturn have large internal heat sources, so equation 12.1 is not applicable). For Venus, a time integration or spatially varying energy balance model would add nothing.
What Postma proposes (if implemented correctly) might make sense for Mars, with a large diurnal cycle and pole-to-equator gradient, with local thermodynamic balances in a column. However, the fact that equation 12.1 does a good job of simulating the actual surface temperature of Mars (which has an optically thin atmosphere) implies that added complexity is not necessary.
For the Earth, the issue with equation 12.1 is how to interpret Te and n. There is no simple way to deconvolute the gaseous greenhouse effect from the radiative emission from clouds. Postma’s proposed model doesn’t help at all with the Earth, because of the complex coupling between the radiation and dynamics. Which is why a dynamical climate model with interactive radiative transfer, water vapor and clouds is needed to get insights much beyond Equation 12.1. Which is what climate scientists have been doing for several decades.
Note to Skydragons: Exercises such as Postma that use (or misuse) the planetary energy balance equation cannot disprove the existence of the Earth’s greenhouse effect. If you want to disprove the existence of the greenhouse effect, you need some sort of alternative explanation for a whole lot of fundamental physics that explains the infrared emission spectra as measured at the Earth’s surface and high above the emitting portion of the atmosphere (see Pierrehumbert). With regards to the magnitude of the Earth’s greenhouse effect, for a given atmospheric thermodynamic state and gaseous composition, the clear-sky (cloudless) radiative fluxes are accurately calculated using sophisticated radiative transfer models that have been validated extensively by the Atmospheric Radiation Measurement program (see this previous thread).
Trying to take the planetary energy balance equation and torture it into something that it was never intended to do is pointless and misleading at best. The planetary energy balance equation is the simplest possible climate model. On the other hand there are the general circulation global climate models, which are of enormous complexity. In between is a whole class of energy balance climate models, which were very popular in the 1950’s – 1980’s, the Wikipedia gives a good introduction to this class of models, which includes box models, radiative-convective models, higher dimension versions of the zero-dimensional planetary energy balance model, and Earth system models of intermediate complexity (statistical/dynamical models). Different models can be used depending the nature of questions asked and the pertinent time scales.
So starting from the simplest zero-dimensional model (planetary energy balance model) and saying that it does not answer all relevant questions and resolve issues related to the diurnal cycle, and therefore the greenhouse effect doesn’t exist, is well, I can’t even find a word for this. Use a higher dimensional model and play around with it, but if the model has the correct physics, the greenhouse effect is not going to disappear. Trying to demonstrate that the greenhouse effect doesn’t exist with one of these models, particularly by applying a particular model for something that is beyond the assumptions built into the model, makes no sense.
Earth is tightly linked to the neutron star at the core of the Sun [1.2]
1. “Earth’s Heat Source – The Sun”,
Energy and Environment 20, 131-144 (2009);
http://arxiv.org/pdf/0905.0704
2. “Neutron Repulsion”, The
APEIRON Journal, in press, 19 pages (2011);
http://arxiv.org/pdf/1102.1499v1
Raymond T. Pierrehumbert
“In a single second, Earth absorbs 1.22 × 1017 joules of energy from the Sun. Distributed uniformly over the mass of the planet, the absorbed energy would raise Earth’s temperature to nearly 800 000 K after a billion years, if Earth had no way of getting rid of it. ”
http://climateclash.com/2011/01/15/g6-infrared-radiation-and-planetary-temperature/
This is incorrect.
You can’t increase the temperature of something higher than source of heat. The sun surface temperature is about 5778 K, and that is as high as the earth temperature could get.
gbaikie,
it’s important to remember that Ray is saying that the earth would be that warm if it had no way to get rid of that energy. So as sunlight is falling on the earth, the amount of energy contained in the earth system would just keep increasing. Since temperature is a proxy for some types of energy (which would also be increasing), it should increase to dramatic levels as well over a long enough period of time.
Also, the interior of the sun is not 6000 K. It’s much, much, much hotter than that precisely because there are physical mechanism that prevent the material in those parts of the sun from losing their energy as quickly as the outer layers exposed to the deep freeze of space.
Does that make a little more sense?
“It’s important to remember that Ray is saying that the earth would be that warm if it had no way to get rid of that energy. ”
My point is simply, earth temperature can not exceed the sun temperature, unless Ray wants to violate more rules of this universe.
So what he said is incorrect and it’s stupid to say it.
Relate to this is chemical rocket fuel has limit of what temperature it can attain- depending on the particular rocket fuel. Hydrogen and oxygen gets pretty hot, gun powder not as hot. This is one reason LH2&LOX is used in rockets, rather than gun powder. It also means you can’t heat up anything higher than max temperature of whatever fuel you are using- regardless of magic substances such as CO2 or smoke&mirrors.
The idiot[s] that said fire doesn’t melt steel, was vaguely close to being correct. The problem is that kerosene could melt steel and steel is weakened in it’s structural strength if it gets, say 50% of the temperature needed to melt it. Kerosene is used to fly airplanes and rockets.
“Also, the interior of the sun is not 6000 K. It’s much, much, much hotter than that precisely because there are physical mechanism that prevent the material in those parts of the sun”
So you trying to help Ray.
If the sun surface reaches 800,000 K, it won’t take a billion years to heat up the earth. And btw, most of it’s energy will be in Xrays or something like that and probably double it’s size. And since interior of the sun is about 15 million degrees and if sun gets to this temperature, someone would have to do the math but time period would be seconds rather than a year or billions of years.
Right.
Got it.
So irrelevant projection from extrapolation of a trend used in an argument from absurdity is absurd for more than one reason.
One presumes that had the initial argument said more accurately that the Earth would approach the heat of the Sun and remain there for several billion years, it would overcome this really nitpicky (in this case) objection, and still result in a successful argument from absurdity that would still prove persuasively to any reader that the Earth has some mechanism for getting rid of incoming energy from the Sun.
Are we satisfied with such an amendment, or does it still distract from the point in some other unimportant (at this point) way?
gbaikie- Raypierre is correct. If Earth could not get rid of the energy it absorbed, its temperature would eventually exceed that of the heat source. Is there a violation of the laws of thermodynamics? Of course, and that was part of Raypierre’s point – a failure to shed heat violates those laws. Your argument is false.
“gbaikie- Raypierre is correct. If Earth could not get rid of the energy it absorbed, its temperature would eventually exceed that of the heat source. Is there a violation of the laws of thermodynamics? Of course, and that was part of Raypierre’s point – a failure to shed heat violates those laws. Your argument is false.”
You could surround earth with a sphere which was heated to same temperature or slightly hotter than earth, and have hole/window in that sphere that let in the sunlight. Thereby without violating the laws of this universe you meet the condition of Earth not able to get rid of energy absorbed- and Earth’s temperature would never exceed the sun’s temperature.
But we don’t need to use the entire Earth- just use mirrors and see if you concentrate the sun energy hotter than 6000 K. Not expensive, and you could win a prize.
gbaikie – I believe you’re still wrong. Your example would allow the Earth to shed heat. For the setup to prevent all heat loss, the “hole” would have to allow only one way energy transfer, which again is the point of Raypierre’s argument. I don’t see any way of getting around his argument.
“I believe you’re still wrong. Your example would allow the Earth to shed heat. For the setup to prevent all heat loss, the “hole” would have to allow only one way energy transfer, which again is the point of Raypierre’s argument. I don’t see any way of getting around his argument.”
The hole to allow sunlight in could be glass [or diamond] and glass could also be heated.
But I think the point I am making is it is at least a debatable point- and Ray is simply asserting something which isn’t scientifically accepted.
I did google search and here is discussion on this exact point. And there is wonderful video posted there:
http://www.youtube.com/watch?v=z0_nuvPKIi8&feature=player_embedded
Posted here:
http://www.reddit.com/r/askscience/comments/ej61k/what_is_the_maximum_temperature_you_can_achieve/
In the video the sunlight is concentrated to a very high temperature but is no where near the temperature of the sun.
gbaikie,
‘But I think the point I am making is it is at least a debatable point- and Ray is simply asserting something which isn’t scientifically accepted.’
Yes, Ray is asserting something that is not scientifically accepted as a part of reality…on purpose.
In reality, there are mechanisms by which the energy deposited into the earth’s climate system by the sun can be dissipated back to space. The most important of those mechanisms is radiative dissipation back to space at the top of the atmosphere.
But in Ray’s ‘thought experiment’, there are no dissipative channels. So that the energy deposited into the earth’s climate system just continues to build up and build up, forever essentially.
Think of it this way. I have a really big bucket I’m trying to hold up. As I’m holding it in the air, the bucket is being filled with water. In order to hold it up (I’m only so strong), I have to poke some holes in the bucket so that, as water is pouring in, some is pouring out.
If I make enough or large enough holes, I can make the rate of water coming out of the holes equal to the rate of water entering the bucket. That way, even though water is still pouring into the bucket, the bucket is not getting any heavier because the same amount of water is leaking out of the holes I’ve made.
This is essentially the situation with the earth system with energy taking the place of water.
Now imagine that somehow I grow a third arm and am able to plug all the holes I’ve made. The water does not stop from entering the bucket, but I have now stopped the flow out of the bucket. So now the bucket will get heavier and heavier and heavier as time goes on (let’s a assume it’s an extraordinarily large bucket).
If we were to plug up the ‘holes’ for the earth by ‘turning off’ the energy dissipation mechanisms, then energy, just like the water in the example above, would continue to build up in the climate system. This energy inevitably manifests itself as an increase in the temperature of the surface and atmosphere.
But your instincts are correct. All of that is just hypothetical. The earth has ways to dissipate energy which is part of the reason we’re here even talking about this.
Does that make a little more sense?
As to exact what temperature the earth could realistically get to, I’m not sure. I’m assume that you’re thinking of the sun as a heat engine from which you’re using the engine efficiency equation to figure the exact temperature out?
I would say it’s not a bad place to start, but I would imagine, and I could be wrong, that figure out the exact number would be a bear of a problem. But I bet you could get a physics PhD doing it…
“If we were to plug up the ‘holes’ for the earth by ‘turning off’ the energy dissipation mechanisms, then energy, just like the water in the example above, would continue to build up in the climate system. This energy inevitably manifests itself as an increase in the temperature of the surface and atmosphere. ”
I don’t think this water analogy is adding any understanding.
But I can’t resist:
At some point the bucket is going to have more mass than the planet, and you will be “lifting” the planet rather than the bucket.
So if you dying to go towards infinite values, the planet’s mass is more important than the bucket.
The planet in this case is the Sun’s 6000 K. And Ray’s number is 800,000 K. Which is analogous standing on very low gravity object holding the bucket and being concerned about the weight of the bucket.
Yes, eventually the metaphor will fall apart, as it’s intended to do by virtue of the fact that it’s meant to show the absurdity of the proposal that Earth might not have any means to get rid of energy, in order to focus the reader’s attention on those mechanisms of getting rid of energy that appear to exist.
Along the way the metaphor might convert from an Earth-sized body approximating a black hole — which would be so awesomely fascinating that its climate would be utterly forgotten in the rush to study the anomalies that ensued — to one that, after absorbing enough energy that its mass grew sufficiently would be a black hole of dubious physical origin (but as state has no memory, who cares), and we’d all be able to forget about climate on the black hole entirely.
Erm, so, are we all agreed, some energy leaves the planet?
“Erm, so, are we all agreed, some energy leaves the planet?”
wiki:”The Earth receives 174 petawatts (PW) of incoming solar radiation (insolation) at the upper atmosphere”
So each second the earth receives 174 petawatts of energy from the Sun, and receives energy from the Moon in terms of tidal energy, and receives energy from radioactive decay in the Earth’s core.
And all that energy is radiated from earth into space every second.
So we have a rather large amount of energy leaving earth.
wiki:”The Earth receives 174 petawatts (PW) of incoming solar radiation (insolation) at the upper atmosphere. Approximately 30% is reflected back to space while the rest is absorbed by clouds, oceans and land masses.”
And considerable amount of solar energy is reflected.
Since we doing analogies and thought experiments. I will do couple more.
What if instead 30% the Earth reflected 100%?
One might reasonably object that 100% is impossible, that only 99. [point something ] would only be possible.
Now can you reflect 100 or 99% if you cover the earth surface with mirrors or do the mirrors need to be above the Earth’s atmosphere?
If the atmosphere had no clouds or dust or any kind particle in the air, and if you covered to Earth with mirrors which were capable of reflecting 99.8% of all sunlight hitting them, what percentage of solar energy would reflected back into space?
Or what would the difference be between mirrors being on the earth surface as compared to mirrors being above the earth’s atmosphere reflecting sunlight?
Is there much difference between mirror on the ground compared to mirrors above earth atmosphere? Is it a difference of say 10% or much higher percentage?
Suppose you at equator with sun directly above you [noon] and the day was without any clouds. And you were at sea level in terms of elevation.
You are going to get about 1000 watts per square meter, meaning one could only reflect 1000 watts per meter. If you were 200 miles higher in same location and time, you could reflect about 1300 watts per meter.
So at 200 miles you reflect about 300 watts per square meter more than if on the surface of earth.
Can we also assume that the sunlight reflected from the earth surface, will lose around another 300 watt before reaches someone at 200 miles?
So guy at 200 miles can reflect with same mirror, 1300 watts per square meter whereas on the ground only 700 watts per square meter reaches space.
And instead sun being directly above you, say it’s 9 am or 3 pm, the mirror on the ground will have more losses.
So if the earth surface is completely covered with mirrors, one should receive about 700 watts per meter of sunlight from earth if you at 200 miles above earth and receive 1300 watts if facing the sun.
So that difference between mirror on the ground as compared to mirrors in space would be significantly different- not 10% or less, but rather around 50% less.
Now you have a earth covered with mirrors with all particles removed from atmosphere [or in the above ignoring them].
Now, let’s add in clouds. Would the addition of normal levels of cloud cover increase, decrease, or more no difference in terms of reflecting sunlight from an earth covered in mirrors?
“The presumption that started the entire conversation is that Pierrehumbert was pointing out that the earth contains channels it uses to dissipate away energy absorbed via sunlight. To make his point, he shows that in the case there were no such channels, the earth’s temperature would be so much hotter than we observe it. ”
No, you are wrong. Since I start this particular conservation [Judith Curry started the main thread, obviously] And I was responding to link she provided in the main article. And topic wasn’t “channels” by which I assume you mean long wave length infrared.
Addressing your issue of “channels”, the earth is a very large object and a large object can radiate into space immense amounts of energy.
In space, huge objects are huge refrigerators space. More specifically in terms refrigerators in space, it’s mainly about amount surface area which can radiate the heat- more surface area more heat you can get rid of.
Conversely, the smaller the object [and less surface area it has] the less energy it can get rid of- via radiation, conduction, and/or convection.
So you take a dime and a blowtorch and you can heat the dime to the same temperature as the blowtorch. You put the dime on a brick [a brick doesn’t conduct heat very well nor is affected much by blowtorch] and you heat the dime to the temperature blowtorch, but you can not heat the dime above the temperature of the blowtorch- by using that blowtorch or much bigger blowtorch.
Fred Moolten: Nothing in the universe allows “only one way energy transfer,” other than a black hole. Thus, Raypierre’s argument is pure nonsense.
gbaikie: thanks for that illustrative video. Now, let’s consider what happens when we concentrate the “backradiation” claimed to have TWICE THE POWER OF THE SUN – IT CAUSES COOLING
HAHAHAHAHAHAHAHAHAHAHA
http://solarcooking.org/research/McGuire-Jones.mht
http://chriscolose.wordpress.com/2010/05/08/stoat-taking-science-by-the-throat-latest-posts-archives-about-rss-contact-profile-me-my-family-and-me-more-make-sure-youre-familiar-with-the-comment-polic/#comment-2363
http://hockeyschtick.blogspot.com/2010/06/why-conventional-greenhouse-theory.html
Good God, folks…This isn’t that hard to understand. Look up the word “counter-factual” in the dictionary. Ray proposed a counter-factual for the sole purpose of giving the physicist audience he was addressing an order-of-magnitude idea of how much energy the earth receives from the sun.
It is really no more mysterious than that. Of course it’s not realistic…It wasn’t meant to be. It was simply meant to illustrate the amount of
energy that the earth is receiving from the sun. In particular, it gets people off on the right foot of realizing that there is no particular temperature associated with the amount of power coming from the sun…but rather that the temperature would increase without bound if the
earth did not radiate energy back out into space. Hence, the average temperature of the earth is determined by the balance between what it receives from the sun and what it radiates back out into space.
This discussion appears mired in a clash of cultures.
Some, though not all, math and science thinking is influenced by repeated presentations of examinations of fact and proofs in exactly the form Ray P. uses: “If A implies B, and B is absurd, then A is false.”
I myself spent four years repeating such logic in two or more lessons a day, five days a week, thirty eight weeks a year. I’m indoctrinated to the form. It’s like second nature, and requires an effort to step back from and examine from the point of view of someone who wasn’t so deeply inculcated to the practices of formal logic.
This practice of formalism — which I haven’t kept up and no longer am very rigorous about — leaves a mark in one’s habits of thought. It only takes a few moments to spot those who are encultured to it from those who just aren’t.
Which may be why this discussion involves so much talking past one another.
Or there really may be people who don’t understand the concept of a black hole, where energy can’t escape, and a model that allows 800,000K temperatures internal to black holes, or that S-B wouldn’t apply normally within a black hole, where many ordinary precepts of physics are suspended.
Bart R 8/23/11, 11:35 am, Planetary energy …
BR: This discussion appears mired in a clash of cultures. [¶] Some, though not all, math and science thinking is influenced by repeated presentations of examinations of fact and proofs in exactly the form Ray P. uses: “If A implies B, and B is absurd, then A is false.”
The formula you recite is called modus tollens (MT) in the propositional calculus of symbolic logic, where it is called an axiom or a rule of inference. Like all axioms and rules of logic, it is an axiom of science.
If your equation did not hold, digital circuitry and digital computers would fail to work. If you find verbal writing or speech where MT is invalidated, you are looking at a sample that is not science (an application of MT).
We have for the heat transferred by radiation between a body at the temperature θ and walls (of an enclosure) at θ_sub_W, Q_dot = Aασ(θ_sub_ W^4-θ^4), where α refers to the temperature θ Zemansky, 4th ed, p. 106. A is the area and α is the absorptivity. [Example Hypothesis] In science, [Example Conclusion] the back radiation illuminating an object minus the object’s forward radiation warms the object.
Your subject post in response to Fred Moolten is well-placed. Dr. Moolten is saturating this blog with the claim that back radiation supplies thermal energy. What he teaches negates the Example Conclusion. Others mired in back radiation give credence to his error. Apply MT to conclude that none of them is practicing science. It’s a clash between science and non-science. E.g.:
The emissivity relevant to heat transfer into the ocean from back radiation relates to the thermal IR range. Week in Review: April 2, 2011 thread, FM, 4/6/11, 10:57 am.
That back radiation contributes more than solar SW direct radiation is well accepted in the literature based on data such as the T-F-K energy budget data cited earlier. Id., 4/7/11, 3:09 pm.
Rather, during a radiative imbalance, surface temperature rises in response to back radiation until incoming absorbed energy and IR flux to space again balance. Slaying the Greenhouse Dragon, Part IV, FM, 8/13/11. 4:11 pm.
Back radiation changes the temperature at which any given lapse rate operates, and so it can increase surface temperature in response to CO2 without a change in lapse rate. Id., 4:55 pm.
Back radiation, which is substantial and has been measured, is an important variable in climate dynamics because of its contribution to the thermal energy of land and oceans. Upward IR radiation is of course equally important, as is the difference between them – the net IR radiation, which is upward at about 60 W/m^2, and thereby helps to balance incoming solar radiation. Merely knowing the latter 60 W figure, however, is inadequate for a full understanding, because it is equally important to realize that it’s the difference between two large fluxes with different sources and destinations, and to know how each flux originates and the temperature with which it’s associated. Planetary Energy Balance thread, FM, 8/22/11, 8:53 pm.
which references an earlier post,
The net IR flow is upward (in a cooling direction – approximately 60 W/m^2), as is necessary for balance, because solar irradiance is downward. Id., 8/23/11, 9:54 am.
In the Kiehl and Trenberth (1997) energy budget, the initial condition that defines IPCC’s radiative forcing paradigm, (AR4, FAQ 1.1, Figure 1, p. 96), the net longwave (IR) flux is 66 W/m^2, corresponding to Dr. Moolten’s 60 W/m^2. It is less than a fifth of the incident average solar radiation at the top of the atmosphere (342 W/m^2). The upward IR is 390, with 350 going into the atmosphere, and the Back Radiation is 324 W/m^2. The following creates a fully equivalent diagram and budget. Reduce the Back Radiation, the Surface Radiation, and the unnamed 350 W/m^2 going into the atmosphere of gases and clouds by any arbitrary amount, X. The bases for the radiation is as arbitrary as 273.15º for converting Kelvin to Centigrade.
Now make X = 324 W/m^2, delete the original Back Radiation along with its arrow, change Surface Radiation to the net of 66 W/M^2, and the unnamed radiation to the atmosphere becomes 26 W/m^2. The diagram turns into a heat diagram instead of a hybrid of heat and radiation. The net radiation is both necessary and sufficient.
Back radiation … has been measured”, but only by calculation when in equilibrium with some forward radiation, such as the detector in an IR thermometer.
If forward and back radiation could be separated from one another as Dr. Moolten does, it would violate the Second Law of Thermodynamics. He would be Maxwell’s Demon (1867).
Bart R 8/23/11, 11:35 am, Planetary energy … Errata
The last 2 paragraphs should have read:
Back radiation … has been measure, but only by calculation when in equilibrium with some forward radiation, such as the detector in an IR thermometer.
If forward and back radiation could be separated from one another as Dr. Moolten does, it would violate the Second Law of Thermodynamics. He would be Maxwell’s Demon (1867).
Jeff, Chris Colose makes the same error. He even describes the upwelling a back radiation components as two separate fluxes…
I really wonder about this. Who taught them these falsehoods?
Jeff Glassman and tallbloke
Here you bring to mind another cultural distinction within the handling of formal arguments: changing topics in mid-argument.
There’s a latin phrase for this sort of hijacking trains of thought, too, but I’m not predisposed to fancy up straight talk at the moment.
Although it’s perfectly valid to question one argument by invalidating it through examining weaknesses in an assumed element of the first argument, there are more and less scientific ways to do so.
So, the first argument being Ray P’s proof that the Earth must lose heat by some mechanism, the underlying assumption being that 800,000K is an absurd temperature for the Earth, some are attacking that underlying claim.
However, this attack is not meant to amend the first argument, which it appears everyone agrees correct by MT, simply having a fine dispute about the nature of the absurdity they’ll allow.
At which juncture, I’d expect some of my professors to fling chalk at them and shout, “Stick to the point!”
Were Ray P’s argument framed in terms of black holes, we would understand that the singularity of a black hole would invalidate application of S-B, Thermodynamics, and even ultimately causality, and no one would be taken seriously for dissecting the absurdity.
As to this new point, meh.
Thermodynamics is difficult enough where strict formalism is observed. The myriad little logical slips and rhetorical tricks introduced by mixing in blog-saturation ratios and silly unphysical models half in one argument and half in another simply leads me to the conclusion that there is no truth to be gained in carrying on the discussion in this vein.
If you want to rehash Fred M’s backradiation, I recommend start fresh, with a clean argument and explicitly stated terms, in some forum that provides interfaces for animations and graphs, and the ability to use the formal symbols of calculus, because these things are best expressed as partial integrals in some places.. and you’re all going nowhere fast with text.
Having skimmed what Fred’s said elsewhere on the blog, I opine that in most cases he’s fairly solid on both formal logic and Thermodynamics, though from time to time he has held to different conclusions than I would make. I won’t pretend to make his argument for him, since he’s certainly brighter than I am and demonstrably better versed in the subject at hand.
Regarding statements made below in this long column, if one wants to measure the back radiation and the upwelling radiation separately, all that is required is to turn the Pyrgeometer to face upward for the former and downward for the latter.
I should have referred to statements that appeared above where my last comment ended up.
Fred Moolten,
No your argument is false. Why? Because you violated radiation laws, in particular Stefan-Boltzmann’s law. Its a common misconcept for the GHE and is a common mistake by the warmists.
” If Earth could not get rid of the energy it absorbed, its temperature would eventually exceed that of the heat source.” You have a big wrong assumption here that if the Earth reached 6000K, the Earth could continue receiving energy from the Sun. No, this assumption violated S-B law.
A lot of people here trying to tell you that GHE violates radiation laws and thermodynamic laws.
It’s this type of physically nonsensical comment we get for promoting the work of the dragons. Now others are realizing that if they just throw a whole bunch of jargon into a comment, some readers might take their overall point more seriously.
I think we can all agree that the dragons are completely mistaken in their promotion of the Johnson and Postma’s work. This work adds nothing to science or individuals’ understanding of physical reality.
In my mind, the battle has been won and because of this fact we just need to move on. If someone in the future is interested in assessing the value of the work that dragons are pursuing, these threads will always be here to help.
But continuing to give a soapbox to a group of people who would just use Boltzmann’s name without giving any respect to the physics he so cared about is a travesty I’ve had enough of at this point.
maxwell,
Violation of radiation laws and thermodynamic laws, you called them nonsense. Here you are and thats what you are.
No Sam,
what makes what you’ve said total nonsense is that you no have context in the current situation. The presumption that started the entire conversation is that Pierrehumbert was pointing out that the earth contains channels it uses to dissipate away energy absorbed via sunlight. To make his point, he shows that in the case there were no such channels, the earth’s temperature would be so much hotter than we observe it.
So instead of actually looking into the context of the actual conversation, you’ve just assumed you knew what you were saying, even though, in the context of the conversation, your point is meaningless.
That’s what’s nonsensical about your point. You’ve done so little work in establishing why Fred would have made that comment that you think he’s saying it as though that’s the way the earth works. That’s obviously incorrect to anyone who has been taking part in the conversation since its beginning.
And it’s that attitude that somehow, even without reference to where the conversation has come from, you think that you can insert your opinion as though no one else has made that point is exactly the type of lazy behavior that has lead to the misapplication or misinterpretation of so much basic physics in thread and similar threads.
maxwell,
No maxwell,
“what makes what you’ve said total nonsense is that you no have context in the current situation.” You totally fit to it and not me.
“The presumption that started the entire conversation is that Pierrehumbert was pointing out that the earth contains channels it uses to dissipate away energy absorbed via sunlight. To make his point, he shows that in the case there were no such channels, the earth’s temperature would be so much hotter than we observe it. ” I agreed to the point that theoretically without the channels it can reach 5778K. Anything beyond is absurd and violated radiation laws, I guess you have not spent enough time to understand them at all.
“So instead of actually looking into the context of the actual conversation, you’ve just assumed you knew what you were saying, even though, in the context of the conversation, your point is meaningless. ” These statements are meaningless and nonsense. You assumed you knew better was just as nonsense as Fred had said.
“That’s what’s nonsensical about your point. You’ve done so little work in establishing why Fred would have made that comment that you think he’s saying it as though that’s the way the earth works. That’s obviously incorrect to anyone who has been taking part in the conversation since its beginning.” You are the true denier of radiation laws and thermodynamics.
“And it’s that attitude that somehow, even without reference to where the conversation has come from, you think that you can insert your opinion as though no one else has made that point is exactly the type of lazy behavior that has lead to the misapplication or misinterpretation of so much basic physics in thread and similar threads.” Thats nonsense. You were very lasy to understand radiation laws and thermodynamics, I cannot help you unless you try hard.
The corona that surrounds the “solar surface” is much hotter (T ~ 10^6 K) than that glowing sphere of waste products (91% H, 9% He) that emits photons (photosphere) and hides the material beneath.
The core of the Sun is nuclear material in a pulsar, not atomic material with kinetic energy that can be measured as temperature. The nuclear material is energized by neutron repulsion (see ref. #2 above) – like violent resentments and anger of the ferocious Hindu Goddess, Kali:
http://www.muktinath.org/hinduism/kali.htm
Surrounding the pulsar is atomic material with the same composition as Earth and ordinary meteorites: Fe, O, Ni, Si, S, Mg and Ca.
Most of those nuclei have zero or even spin, satisfy Bose-Einstein statistics, and may become a super-fluid super-conductor.
Barry W. Ninham, “Charged Bose gas in astrophysics”, Physics Letters 4 (1963) 278-279.
Sunspots and solar eruptions arise from deep-seated magnetic fields:
a.) The neutron star in the solar core, or the
b.) Super-conducting, iron-rich material around the solar core
“Super-fluidity in the solar interior: Implications for solar eruptions and climate”, Journal of Fusion Energy 21 (2002) 193-198:
http://arxiv.org/pdf/astro-ph/0501441
AGW is built on the false premise that the Sun is Earth’s steady source of input heat.
http://dl.dropbox.com/u/10640850/20110722_Climategate_Roots.pdf
Oliver,
“The corona that surrounds the “solar surface” is much hotter (T ~ 10^6 K) than that glowing sphere of waste products (91% H, 9% He) that emits photons (photosphere) and hides the material beneath.” I am an ignorant of the Sun’s matter beneath the hydrogen-helium atmosphere. You have just opened up my mind that:
“Surrounding the pulsar is atomic material with the same composition as Earth and ordinary meteorites: Fe, O, Ni, Si, S, Mg and Ca.”
I thought the Sun composed of hydrogen and helium only. Thanks.
Presumably, the solar system planets and meteorites were spinned off from the Sun due to a large explosion.
“The sun surface temperature is about 5778 K, and that is as high as the earth temperature could get”
The explain how the solar atmosphere can be in excess of 1 million degrees?
Yes, I would also like to know.
It seems to me there is contradiction on the theory that the Sun’s surface temperature is only 5778K and at this temperature, nuclear fusion is not possible unless the surface is over one million degrees.
If the Sun’s core is over 1 million degrees, then within the radius of the Sun + the Sun’s atmosphere, the temperature cools down to 5778K. A huge temperature gradient on the Sun. The Sun’s temperature gradient is larger if the Sun’s ground (if there is one) surface is 1 million degrees. Gravitational force is huge on the Sun to confine hydrogen at 5778K within the Sun’s atmosphere.
Is the Sun’s core made up of compacted neutrons and protons only? Nothing to do with hydrogen and helium?
“explain how the solar atmosphere can be in excess of 1 million degrees?”
I don’t think there is a known answer- perhaps someone would like to suggest the is some CO2 near the sun.
But there is also a very hot atmosphere above earth, call the thermosphere:
“Among the four atmospheric temperature-defined layers, the thermosphere is located highest above Earth’s surface, beginning at about 57 mi (90 km) above Earth, and reaching into about 300 mi (500 km) height. The name of this layer, thermosphere, originates from the Greek thermo, meaning heat, because in this layer the temperature increases with altitude reaching temperatures higher than 1830°F
(1000°C).”
http://www.enotes.com/earth-science/thermosphere
So ISS is flying thru the thermosphere- and the heat isn’t unbearable:)
If I had to guess about the Sun’s corona- but first this is what wiki says:
“The exact mechanism by which the corona is heated is still the subject of some debate, but likely possibilities include induction by the Sun’s magnetic field and sonic pressure waves from below (the latter being less probable now that coronae are known to be present in early-type, highly magnetic stars)”
I think a relation to sun’s magnetic field is likely [and gives spectum of Fe at 1 million degrees] but would also throw in possibility that atoms could in orbit around the sun. And orbital speed that near the sun is very fast. And there is enough of them there that they could hitting each other. They could also be hitting particles of solar eruption [CME] and solar wind in general.
So collision and/or magnetic fields crossing another magnetic fields [and this imparts energy]. So if mostly collisions then one has a faint ghost of what happens in a Quasars and accretion disc [though it’s not disc- and not disc because {I would I guess} atoms are constantly being added {and lost}].
Diviner observes cooling during June 15 total eclipse
“The following plot shows data taken during successive orbits over a unit of lunar mare situated between 32 and 33 degrees north. The orbit path progressed from east to west (right to left), with each orbit separated by roughly two hours. The first two data swaths were taken before the eclipse, the three center swaths were taken during the eclipse, and the last two swaths were taken after the Moon had reemerged from Earth’s shadow. The data show an average decrease in surface temperature during the eclipse of around 100K, with some locations remaining warmer than others.”
http://www.diviner.ucla.edu/blog/
Dr. Curry,
If you can’t even comprehend the difference between the ‘Slayers’ (GHE critics) and the ‘Sky Dragons’ themselves (GHE believers) what hope do we have of persuading you that you’ve erred on the science?
This further confirms to me you’ve not even read our book. Not good.
I hope somebody has a list of the quantities that have actual measurements? Or link.
This was discussed on the confidence in radiative transfer models. see http://www.arm.gov
Dear Dr. Curry:
With all due respect, I have a problem with interpretations in Section 14.3, planetary energy balance: Why is the difference between Te* and T0 is attributed to greenhouse effect and not something else?
Dr. Curry:
You have not addressed my question above, and I have another question :We learned at school that atmospheric layers, or slabs, cannot exchange radiations between them for there is no interface between them. The atmospheric air is one homogeneous air mixture and acts as such. Atmospheric air can only exchange heat, within, by convection and conduction. How come, in Section 14.3 Planetary energy balance, you are assuming that atmospheric layers or slabs exchange solar radiations between them? Where is the physics that supports your assumption?
Does surface water layers, or slabs, exchange radiations between them?
Nabil, if you want the whole enchilada, look at general circulation climate models with interactive radiative transfer, thermodynamics and dynamics. If you want simple models to aid conceptual understanding, then you need to accept some approximations.
This statement is completely false, and if you learned this in school, it was a lousy school:
“We learned at school that atmospheric layers, or slabs, cannot exchange radiations between them for there is no interface between them. The atmospheric air is one homogeneous air mixture and acts as such. Atmospheric air can only exchange heat, within, by convection and conduction.”
Molecules in the atmosphere with a favorable molecular structure (e.g. H2O and CO2) emit and absorb infrared radiation. Read Pierrehumbert, and numerous previous posts, I am not going to explain how this works here. Until the skydragons can understand and accept this, we can’t get anywhere with talking about thermodynamics etc.
We just had a long and interesting discussion on WUWT regarding the inability of longwave radiation to penetrate the ocean. What proportion of the energy in downwelling longwave do the GCM’s have being propagated into the ocean bulk from the surface by mechanisms such as turbulent convection?
Dear Dr. Curry:
My schools are excellent and produced Fermi, Marconi, and Copernicus, to name a few. I am confident that they taught me a correct science.
Nabil Swedan
One must admit cause to believe none of Fermi, Marconi, or Copernicus ever said of their schools (as excellent an education as Bologna might rightly claim to offer) that they were confident they learned from them correct science.
Else, which of them would have gone on to so overthrow the science that came before them? ;)
Do they still teach the quality of critical thinking that allows one to, for oneself, examine a proposition by logic and reason, and through observation and experiment, determine one’s own thoughts on the matter without reference to authority?
“Molecules in the atmosphere with a favorable molecular structure (e.g. H2O and CO2) emit and absorb infrared radiation. Read Pierrehumbert, and numerous previous posts, I am not going to explain how this works here. Until the skydragons can understand and accept this, we can’t get anywhere with talking about thermodynamics etc.”
Your reference doesn’t claim that oxygen and nitrogen don’t also emit and absorb infrared radiation. Or that there is any substance in existence that doesn’t emit and absorb infrared radiation.
Btw, I wondering why the plank curve is for 260 K.
Earth average temperature is closer to 290 K.
And Venus obviously higher and Mars obviously colder.
Could a possible answer be that actual scientist aren’t interested in such concepts as “average global temperature”- meaning it’s irrelevant
in terms of scientific inquiry?
Dr Curry,
[“Molecules in the atmosphere with a favorable molecular structure (e.g. H2O and CO2) emit and absorb infrared radiation. Read Pierrehumbert, and numerous previous posts, I am not going to explain how this works here. Until the skydragons can understand and accept this, we can’t get anywhere with talking about thermodynamics etc.”]
The problem is not with accepting the ability of CO2/H2O to emit and absorb radiation, it is, in terms of cAGW, the AMOUNT of contribution these gasses have to the GHE. Pierrehumbert gives a far greater contribution to CO2 than any existing data can support. In the dry atmosphere. 99.96% of the atmosphere cannot contribute to GHE within the relevant wavelengths. The other 0.04% consists of the trace dry radiative gasses, mostly CO2. If you add water vapour – say 2.5% on average, making a total of 102.5% – then you have 2.54% able to either emit or absorb radiation (although I’m not sure that water emits much in the relevant wavelengths, but it is certainly the largest absorber) but still have 99.96% of the atmosphere unable to contribute. Either way, the contribution of dry radiative GHGs to the GHE is minimal. This can be seen using any dataset of sufficient history, such as HadCRUt. If, as Pierrehumbert says, CO2 contributes 30% to the GHE, then how has that contribution been almost entirely negated following a significant increase in CO2? ‘Negative feedbacks’ and ‘Thermal inertial lag’ do not explain this anomaly.
If no-one can answer the question ‘How much does CO2 contribute to the GHE?’, then how can anyone make statements which consistently assume that the contribution is significant?
I don’t know anyone who seriously believes there is no such thing as a GHE. It is the assumption that the GHE is largely due to CO2 that I, for one, find hard to accept.
The basis upon which the entire cAGW debate has been formulated requires a complete rethink from the start. Arrhenius may have had a point in stating CO2 would contribute to GHE, but he has been hopelessly inaccurate in any quantitative sense.
Pierrehumbert has some work on the cited claim, such as his 2007 paper, and there have been other experiments along similar lines (Kiehl and Trenberth 1997, and most recently Schmidt et al 2010). They all give relative contributions of CO2 at ~20% in a cloud atmosphere and a bit more in clear skies.
And a minute’s thought will tell you that they are all way wrong. How many of those papers are based on experimental data and, if so, where is it?
.
Here’s the rub. In 1850 the CO2 atmospheric concentration was appx 280 ppmv. The global temperature was appx 0.8 deg C less than it is today. This means the GHE was appx 32.2 deg C (given that most players think it is 33 deg C today). Today the CO2 concentration is 395 ppmv, an increase of 40%.
.
So, if Pierrehumbert and K&T and Schmidt (and Lacis) are correct, the contribution of CO2 was appx 6.5deg C in 1850 and 6.6 deg C today!.
So, a 40% increase in the largest trace dry radiative gas (and similar increases in the others) has led to a 0.1 deg C increase in the GHE in 160 years!
.
So what’s all the fuss about? The logical answer is that the radiative theory, upon which the cAGW hype is based, is demonstrably nonsense in any quantitative sense.
.
What did Arrhenius predict? A sensitivity of 4 to 6 deg C? Yeah, right…
Arfur Bryant | August 20, 2011 at 4:37 pm |
And then had to revise that to 1.5-2º C
Svante Erroneous
GHE = green house effect or global heat engine?
Green house effect. Sorry, should have made it clear.
Given how little CO2 there is in the atmosphere, a mere 400 ppmv or 0.04%, it is understandable that people find it hard to believe that such a tiny amount could have any significant impact on surface temperature.
The reason a very small amount can have a big effect is that it is not the quantity of CO2 that is relevant but its percentage rate of change.
When CO2 increases at a given percentage rate, that is, in geometric progression, it causes the surface temperature to rise at a fixed rate, that is, in arithmetic progression. Surface temperature increases logarithmically with CO2.
This means that an increase from 100 ppmv to 150 ppmv raises the temperature by about the same amount as an increase from 1000 ppmv to 1500 ppmv, which in turn is about the same amount as an increase from 100000 ppmv to 150000 ppmv, that is, from 10% to 15% of the atmosphere.
If you can accept that increasing CO2 from 10% to 15% of the atmosphere would have a significant effect, then you should expect that increasing it from 0.01% to 0.015% will have the same effect.
The global warming of the past few decades is not the result of CO2 having reached an outrageous value like 0.5% of the atmosphere. It is the result of CO2 increasing lately at the outrageous rate of 0.5% per year, up from 0.3% per year four decades ago. Putting it more constantly, anthropogenic CO2, defined as the surplus over the natural base of 280 ppmv, has been increasing by a steady 2.2% a year since 1958 when the CO2 observatory at Mauna Loa was established.
There is no record anywhere, neither in books nor the rocks, of CO2 ever having risen at this rate before, whether a hundred, a thousand, a million, or a billion years ago. This is an astonishing rate, and it is what is responsible for the last few decades of increasing temperature.
The temperature rise expected from such a rate of increase can be predicted from our understanding of the absorption properties of CO2. From 1970 to 2000, CO2 rose 13%. Assuming an immediate response to CO2 and a climate sensitivity of 1 °C per doubling, the temperature would therefore rise 1*lb(1.13) = 0.17 °C, while with 3 °C/doubling the rise would be 0.5 °C. Since the observed rise over that period, was 0.5 °C, somewhere between zero and 0.33 °C of that rise must be of some other origin.
But the IPCC has suggested a delay of 20 years in its concept of transient climate response, meaning the time it takes CO2 to have its warming effect. With that assumption we should base these calculations on the CO2 rise not from 1970 to 2000 but from 1950 to 1980, which was around 8.7%. This shrinks the above two numbers to 1*lb(1.087) = 0.12 °C and 3*lb(1.087) = 0.36 °C. In that case we would have between 0.14 °C and 0.38 °C not accounted for by CO2.
These defects should not be at all surprising in light of the large variations in temperature observed during 1850 to 1950, which can hardly be the fault of CO2 given that in 1900 we were producing CO2 at only 6% of our present rate.
One can then ask whether it is possible to pin down both climate sensitivity and natural variation any more accurately than this.
I believe we can, and that very close to two-thirds of the observed temperature increase from 1970 to 2000 was of anthropogenic origin. This is a preliminary estimate based on a study of the global land-sea temperature records since 1850 in combination with estimates since 1751 of combustion of gas, liquid, and solid forms of carbon based fuel including gas flaring, plus CO2 from cement production.
If 1970-2000 saw CO2 contributing 66% of total warming, one can ask what percentage it contributed from 1940 to 1970. Well, in fact the observed temperature declined some 0.08 °C over that period. Had the CO2 level remained constant I estimate that it would have declined by 0.26 °C. So CO2 merely prevented what would have been even more significant cooling.
More on this later (preliminary ≠ final).
Hello Vaughan!
Once again, my old internet friend, you are arguing based on an assumption.
[“This is an astonishing rate, and it is what is responsible for the last few decades of increasing temperature.”]
You ignore the fact that there has been no increased warming for the latter (nearly) half of your ‘last three decades’ period, during which you say the effect of CO2 should be increasing at an accelerative rate. If your 20-year lag was a valid argument, we should be seeing some increase in the global temperature due to CO2. You assertion that any current warming is due to CO2 is a triumph of hope over objectivity.
You also state that, during the period 1970-2000, CO2 produced 66% of global warming. But, in that case, the period 1910-1945 something else produced 100% of the global warming (0.8 C). Was there no effect from CO2 then? Had CO2 not been produced for more than 20 years?
You are, in my opinion, correct in your assertion that any warming is due to a combination of natural and anthropogenic factors. However, what neither you – nor anyone else – can state is the relative contributions of either. Observed data indicates that there have been several warming periods since accurate records began in 1850. Observed data indicates that CO2 has increased at a slightly accelerative rate since the Mauna Loa dataset was started. What has not been observed is any correlating acceleration (other than short-term intermediate periods) between global temperature and CO2.
It is quite simple. Instead of regurgitating various spurious reasons why the anticipated effect of CO2 has not lived up to Arrhenius’s expectations, why not simply address the logical possibility that he was just plain wrong in any quantitative sense?
Regards,
You ignore the fact that there has been no increased warming for the latter (nearly) half of your ‘last three decades’ period, during which you say the effect of CO2 should be increasing at an accelerative rate.
Evidently you haven’t heard of El Nino solar cycles, Arfur. These are strong swings that go up and down every five and eleven years respectively. They have no significance whatsoever for long-term climate. They have been happening for hundreds of years and in all probability for millions of years.
You are simply exploiting the most recent El Nino and solar cycle to claim that temperature must be declining. Claims based on short-term events have no relevance to long-term projections.
Unless you filter out short-term transients like El Nino and solar cycles, you will be able to prove on an upswing that the temperature is going up and on a downswing that it is going down. These swings are meaningless for projections twenty years hence.
Evidently you haven’t heard of El Nino solar cycles, Arfur. These are strong swings that go up and down every five and eleven years respectively. They have no significance whatsoever for long-term climate. They have been happening for hundreds of years and in all probability for millions of years.
A statement that requires some validation,
[” August 21, 2011 at 3:28 am |”]
I’ll ignore the sarcasm Vaughan. What you evidently ignore is that – by your own admission – there have been several El-Whatsit cycles since 1850 and yet the global temperature has increased by only 0.8 deg C.
I didn’t hear any warmist say, in 1998, that the Hockey Stick peak “was just an example of an El Nino and the temperatures will not increase at all over the next thirteen years…”
You, along with all the others who believe in the cAGW theory without question still refuse to answer the basic questions: “What is the contribution of CO2 to the GHE?” and “Why is there no acceleration in warming in spite of the slight acceleration in CO2 concentration?”
The overall trend in 160 years is 0.06 deg C per decade (HadCRUt). It is far lower than it was in 1888!
What you evidently ignore is that – by your own admission – there have been several El-Whatsit cycles since 1850 and yet the global temperature has increased by only 0.8 deg C.
Arfur, your logic has gotten even worse lately. You can’t infer from the fact that someone has admitted something that they are ignoring it.
The 3-7 year El-Nino events and episodes have no evident long-term impact on climate, and should therefore be removed from the temperature record in order to see more clearly those factors that do have a long term impact.
I didn’t hear any warmist say, in 1998, that the Hockey Stick peak “was just an example of an El Nino and the temperatures will not increase at all over the next thirteen years…”
Neither did I. It would be completely illogical to say such a thing about a rise that took place over a 30-year period.
You, along with all the others who believe in the cAGW theory without question
It is illogical to say that someone who is attacked for questioning cAGW theory does not question it.
still refuse to answer the basic questions: “What is the contribution of CO2 to the GHE?” and “Why is there no acceleration in warming in spite of the slight acceleration in CO2 concentration?”
That’s like saying that Charlie Brown still refuses to kick Lucy van Pelt’s football.
Arfur, we had a great many exchanges in the past where I patiently tried to answer your questions, and to explain why your reasoning was illogical. If anyone refused it was you: you refused to accept that you were being illogical, and continued to trot out the same illogic, not just to me but to everyone silly enough to engage with you. I now refuse to answer further questions from you, there is no point. The argument you love the most is the following.
The overall trend in 160 years is 0.06 deg C per decade (HadCRUt). It is far lower than it was in 1888!
Officer: “I clocked you at 100 mph, let me see your license.”
You: “But officer, my average speed over the last 24 hours has been only 3 mph, far lower than the 30 mph I was doing 22 hours ago.”
Officer: “You argue like that chap Arfur Bryant over on Climate Etc.”
Vaughan,
Yes, we had many exchanges in the past. And the illogic shown was yours, not mine. Your hubris knows few bounds. It is a shame that you refuse to answer the most basic of questions and yet you can proudly insist that I am the one who is illogical. I am very happy for you not to engage with me, however there are a few points that need qualifying lest you continue to inhabit the warmist pseudo-world without the requirement for objectivity. Nice try at deflection but no cigar I’m afraid.
“The 3-7 year El-Nino events and episodes have no evident long-term impact on climate, and should therefore be removed from the temperature record in order to see more clearly those factors that do have a long term impact.”
It was you that brought up the El Nino etc cycles. Of course they are irrelevant to the long term climate, that was my point! Since 1998 there have been two3-7 year cycles and yet the temperature is still lower than 1998 – hence your use of them as an excuse was false. This makes your 30-year argument invalid. There is NO correlation between accelerating CO2 and global temperature. Get it?
“It is illogical to say that someone who is attacked for questioning cAGW theory does not question it.
Again, that is my point. I attack it and question it, you do not. Your belief in the theory based on radiative forcing is just a belief. There is nothing scientific about your approach.
“That’s like saying that Charlie Brown still refuses to kick Lucy van Pelt’s football.”
This statement, like your following attempt at sarcasm-based humour is well beneath you, Vaughan. Once again you try to deflect the argument because you cannot counter-argue using either logic, science or intellect. You really need to understand the following: The overall trend is 0.06 deg C per decade. There is NO acceleration in this trend apart from short-term, interim periods. The overall (nb) trend has been much greater than 0.06 deg C per decade, particularly in the late nineteenth century. However, the point is the OVERALL trend is much lower today. This means your warmist assertion that CO2 leads to an acceleration of global warming is NOT supported by evidence. No amount of deflection on your part will change this simple fact.
If, Instead of providing evidence, all you have is a puerile attempt at sanctimonious ridicule, then you are not worthy of debating. Stick to the facts, stick to at least some semblance of objectivity and you might see the light.
Please note that I, unlike you, feel no desire or requirement to resort to pathetic sarcasm and cutesy (and erroneous) little analogies.
It was you that brought up the El Nino etc cycles. Of course they are irrelevant to the long term climate
Good, then you should have no objection to removing short-term events like the 3-7 year El Nino and 11-year solar cycles. This is easily done by smoothing the temperature record with a moving average of 11 years, as a definition of long term climate.
The overall trend is 0.06 deg C per decade. There is NO acceleration in this trend apart from short-term, interim periods.
The long term climate record does not bear this out, having been on a steady rise since 1970, with insignificant downturns in the vicinity of 1980, 1987, and 2005.
That’s better, Vaughan. Isn’t it nicer to debate without the yucky personal stuff?
“Good, then you should have no objection to removing short-term events like the 3-7 year El Nino and 11-year solar cycles. This is easily done by smoothing the temperature record with a moving average of 11 years, as a definition of long term climate.”
A nice attempt at moving the goalposts Vaughan. I never said anything about 11-year solar cycles but I can see why you would want to sneak that little gem into the discussion. OK, You like to remove the cycles by smoothing over ELEVEN years? Wow. Personally, I prefer to look at the actual data and accept that the cycles may or may not exist. I don’t hide them, I can interpret the overall trend without smoothing. Look at the same data without any smoothing:
http://www.woodfortrees.org/plot/hadcrut3gl/mean:1
See how the two graphs look so different? Same data, different picture. Except mine is unaltered. Unadjusted. The simple truth.
So lets address your graph, the one with an eleven year smoothing. Look carefully at your graph. You stated earlier that the warming of the last 30 years is due to accelerated CO2 concentration rate (as opposed to simply the concentration). Could you explain what caused the warming that occurred (in your graph) between about 1910 and 1940? Measure it. The warming is EXACTLY the same as the later warming from 1970! Amazing. No CO2 acceleration but exactly the same warming! SO, according to your graph ‘something’ caused an exactly similar warming period but then ‘something’ also caused a sharp drop in temperature between 1940 and 1960. All this before your quote:
“The long term climate record does not bear this out, having been on a steady rise since 1970, with insignificant downturns in the vicinity of 1980, 1987, and 2005.”
So your ‘long term climate record’ says a lot more than your interpretation without your cherry-picking of interim periods.
.
So what do you think that ‘something’ is, Vaughan? How do you explain an exact similarity without your cause? How do you know that CO2 caused the latter warming period but not the earlier warming period?
Now look at my graph. Now look at yours. They both show the simple fact that the TOTAL warming is a mere 0.8 deg C in 160 years. They both show that there have been periods of warming in the past, as well as periods of cooling (and certainly not insignificant ones, as you suggest). They also both show that the warming trend is about 0.06 deg C per decade. You wish – because you want to maintain your belief in the radiative forcing theory of cAGW – that the latter warming is due to CO2. What you’re not prepared to do is look objectively at the data and embrace the logical possibility that you CANNOT say with any certainty that CO2 is responsible for global warming.
You stated earlier that the warming of the last 30 years is due to accelerated CO2 concentration rate (as opposed to simply the concentration).
You aren’t paying attention. It’s not all CO2. What I wrote in this thread on Saturday, that prompted your response, was that
very close to two-thirds of the observed temperature increase from 1970 to 2000 was of anthropogenic origin. I don’t know what proportion of that two-thirds is due to CO2 but I would be surprised if it were less than a half. I estimate the other one-third to be mainly due to the same natural processes that contributed in part to the 1910 to 1940 rise, to which anthropogenic influences also contributed though not as much as now.
They also both show that the warming trend is about 0.06 deg C per decade.
You aren’t paying attention. What I wrote earlier was that the same line of reasoning shows that an average speed of 3 mph over a day proves that you couldn’t have been speeding at 100 mph recently. The relevance of this to CO2 and our other emissions is that for most of the past 160 years we haven’t been emitting much CO2, in fact two-thirds of emitted CO2 has been in the past one-quarter of that period. In those four decades we’ve been pushing the pedal to the metal and now we’re being pulled over. And you’re arguing with a straight face that the average over sixteen decades constitutes mitigating circumstances?
If your logic works differently then it’s too advanced for me, I’m unable to distinguish it from magic. I’m afraid I will have to throw in the towel.
I didn’t respond to the following exchange at first because I couldn’t make head or tail of it.
VP: It is illogical to say that someone who is attacked for questioning cAGW theory does not question it.
AB: Again, that is my point. I attack it and question it, you do not.
I kept trying to understand it, and finally concluded that your reply is such a non sequitur that I have to wonder if you can even read English.
It is a complete waste of time arguing with someone who can’t even understand what the other side said.
Vaughan, Vaughan…(sigh)!
Of course you can throw in the towel but don’t pretend the reason is anything other than you cannot either formulate a reasoned debate or that you have no answer for the points or questions that I raise. Before I go I need to clarify your attempts at deflection…
“You aren’t paying attention. It’s not all CO2. What I wrote in this thread on Saturday, that prompted your response, was that very close to two-thirds of the observed temperature increase from 1970 to 2000 was of anthropogenic origin. I don’t know what proportion of that two-thirds is due to CO2 but I would be surprised if it were less than a half.”
No Vaughan, it is you that is not paying attention. You also wrote this:
“There is no record anywhere, neither in books nor the rocks, of CO2 ever having risen at this rate before, whether a hundred, a thousand, a million, or a billion years ago. This is an astonishing rate, and it is what is responsible for the last few decades of increasing temperature.
So you clearly have laid the fault of global warming at the doorstep of the rate of increase of CO2.
But lets examine your figures more closely…
You state that 66% of the warming between 1970 and 2000 is anthropogenic and, of that, at least 50% (your estimate, not mine) of that 66% is due to CO2. Ok, you’re the Maths professor but I reckon that makes CO2 responsible for 33% of the total warming in that period. Now, according to your beloved ELEVEN year smoothing graph of that period…
http://www.woodfortrees.org/plot/hadcrut3gl/from:1970/to:2000/mean:132
… the warming is 0.3 deg C (If you look at the monthly data it is actually about 0.2 C. This makes CO2 responsible for a mind-blowingly huge temperature increase of, er… 0.1 deg C. Wow! Just Wow! And, what’s more, seeing as how you insist that anthropogenic factors, including CO2 would have a much smaller contribution for all earlier warmings since ‘accurate data’ began, then you are effectively saying that CO2 cannot be responsible for more than – what, 0.2 C in the period 1850-2000? Obviously, the rate of CO2 increase, having latterly been much more pronounced, the contribution is much greater in the last 30 years (1980-2010) – so 33% of 0.3 C = 0.1 C but some of that is already included in the 1970-2000 period – which means that the total contribution of CO2 by your own admission is about 0.25 deg C in 160 years! Again, Wow!
When you have more time and you can refrain from the snarky comments, maybe you could go into more detail about how you think the radiative properties of a trace gas existing at less than 400 ppmv in the atmosphere can possibly be the “responsible for the last few decades of increasing temperature”.
Seriously, I’d love to hear it!
As to your references to the genuinely ridiculous traffic analogy, you are just wrong. Its not a line of reasoning; it is a fact. The overall trend is 0.06 C per decade. If you disagree, instead of using sarcasm, why not just state what you think it is?
Finally, as for this:
“VP: It is illogical to say that someone who is attacked for questioning cAGW theory does not question it.”
I don’t understand it either – are you saying it is YOU who questions cAGW? I think not, chum.
The rest of your post is just infantile snark, and falls far below the level of debate expected here. IMO.
You also wrote this: “There is no record anywhere, neither in books nor the rocks, of CO2 ever having risen at this rate before, whether a hundred, a thousand, a million, or a billion years ago. This is an astonishing rate, and it is what is responsible for the last few decades of increasing temperature.
So you clearly have laid the fault of global warming at the doorstep of the rate of increase of CO2.
Touché. Had I been choosing my words more carefully I’d have written “and CO2 and other human emissions are what is responsible for two thirds of the last few decades of increasing temperature.” I apologize for my sloppy wording.
But lets examine your figures more closely…
You state that 66% of the warming between 1970 and 2000 is anthropogenic and, of that, at least 50% (your estimate, not mine) of that 66% is due to CO2. Ok, you’re the Maths professor but I reckon that makes CO2 responsible for 33% of the total warming in that period.
Now you’re the one being sloppy. But if you replace “33%” by “at least 33%”, then yes, your math is spot on.
Now, according to your beloved ELEVEN year smoothing graph of that period…
http://www.woodfortrees.org/plot/hadcrut3gl/from:1970/to:2000/mean:132
… the warming is 0.3 deg C (If you look at the monthly data it is actually about 0.2 C. This makes CO2 responsible for a mind-blowingly huge temperature increase of, er… 0.1 deg C.
Hey, I appreciate your m.o. there, Arfur. Your argument is worth a 5 on a scale that gives a 6 to Easterbrook’s famous proof that MWP is warmer than “now” and an 8 to Huffman’s less famous but very deserving proof that CO2 isn’t warming Venus.
What you’re exploiting here is the obscure fact that an 11-year moving average knocks 11 years off the window. Hence your alleged graph for 1970-2000 (it was never mine) only shows the 19 years 1975.5-1994.5 (look at the x-axis if you don’t believe me, 1970 and 2000 are nowhere to be seen). Naturally 19 years didn’t warm as much as 30 years, and not even in proportion given that the last 5.5 years are steeper than the rest.
The correct graph for the full 30 years from 1970 to 2000 is this one. It shows a rise of 0.49 °C over those 30 years.
I really like your graph, it’s a big improvement over the point you and Girma keep making that the global temperature has only been rising at 0.06 °C per decade when averaged over the last 160 years, which is worth a 2 at best. You’ve clearly raised your game and are approaching the level of professionals like Easterbrook and Huffman.
The rest of your post is just infantile snark, and falls far below the level of debate expected here. IMO.
Ah, you’ve mastered Internet-speak. Go to the next level.
Vaughan,
You introduced the eleven year smoothing, so don’t complain when I throw it back at you. Its really cute to keep changing the goalposts but you might want to check the warming since your cherry-picked period of 1970-2000 (or 1965.5-20005.5001) and check how much warming could have been attributed to CO2 at at least 33.3%.
.
Anyway, what is wrong with Girma and I pointing out the average trend over 260 years = 0.06 C per decade? Do you have another figure?
Dear Mr. Bryant:
An observation preceded good science, not the GHE science.You will find in my comments later that the GHE exists only on paper and does not exist in the real word. It is an imaginative concept that invented out of the blue to explain global warming. I do not believe in GHE science at all, it is flawed, and has devoured quite a bit of our resources already. Look at the price of corn, it has jumped from less than two dollars to over seven dollars in a short period of time. GHE suggests that there will be a run-away surface temperature and dooms’ day, which is not going to happen. In fact this warming trend will cease on its own without human intervention. These are some of the costs of adopting a false science.
Dear Mr Swedan,
Thank you for your post. I am very sorry not to have replied earlier – I was too engrossed in my discussion with Vaughan and actually missed your input! I will read your other posts but, in the meantime, I agree that ‘GHE science’ has been invented to engender a false fear in order to enforce governmental policies. I find it hard to believe so many so-called scientists can be prepared to religiously believe in a concept that has virtually no observational evidence to support it, and no logical or intellectual foundation in its expected impact.
Regards,
Radiation can be exchanged between different parts of a gas. An opaque gas emits and absorbs like any material. The division into “slabs” is purely for intuitive convenience. The same result arises (but less easily) treating them as continua.
Surface water layers do indeed exchange radiation between them, As do the layers of solid opaque materials, too. These internal exchanges, being bidirectional between materials at virtually the same temperature and with the same properties, cancel out, and only the surface exchanges have any net effect. But the internal exchanges do exist. Treating a material as if it only emits at its surface boundary is another one of those intuitive approximations.
Dear Verba,
Solid layers exchange radiations between them??!!! Do you have a reference book or the name of the discoverer of this phenomenon? I have never heard of this. I know that radiation occures between two surfaces that have a space between them. When these surfaces come to be in contact with each other, radiation heat transfer process ceases, and conduction is the only heat transfer process between the two surfaces.
The same is true for gases and liquid, their layers have no interface between them, and only conduction and convection can occur within a liquid or gas mass.
How would a book help, if you don’t trust them?
Radiation and absorption are atomic/molecular processes. A molecule in the middle of a body of fluid (or solid) does not behave any differently from one at the surface – if it is excited by thermal collisions/vibrations, it can radiate the energy.
In an opaque material, the radiation doesn’t get far, getting re-absorbed within a few molecules distance. Since the energy flows equally in all directions, it cancels out, and can be safely neglected. A lot of elementary introductions to the subject do so – and no doubt that’s what you’ve seen. But if you suspend a detector in an opaque fluid, or a light source, radiation and absorption are found to work the same way throughout the bulk as they do at the surface.
At an intermolecular scale, there is always a gap.
What did you think was stopping molecules inside a fluid radiating?
Dear Verba:
At the molecular level, the molecules of a homogeneous gas or liquid are at the same temperature. No heat transfer of any sort is expected between these molecules.
“No heat transfer of any sort is expected between these molecules.”
Quite so. But you agree they will still radiate, yes?
NiV, while I fully agree with you that radiation exists within solids, I’d be very interested to know the typical energy ratio between phonons and photons in a solid like NaCl crystals or cast iron. I’ve plowed through some 15 volumes of the Solid State Physics series in the hope of running across a hint, so far without success.
“I’d be very interested to know the typical energy ratio between phonons and photons in a solid like NaCl crystals or cast iron.”
I don’t know. I’ve an idea radiative heat transport tends to be only practically important for semi-transparent and porous materials at high temperatures – most of the research I’ve heard of is for application in glass furnaces, although there’s a certain amount for work for use on lasers, ablative coatings, protective coatings for high temperature applications, etc. The nearest to the optically thick domain I can think of would be Rosseland theory for photon transport deep in stellar cores. There may be something there you can use.
But I would guess that the spectrum of internal photoemission is much the same as at the surface, and you could determine the radiative energy density by treating it as slabs of material just thick enough to be opaque.
Opacity isn’t a binary property. If you spread even a metal, like gold, out into a thin enough layer on glass, you can see through it. So the principle is the same as for a ruby, but with a much, much shorter mean free path.
Opacity isn’t a binary property. If you spread even a metal, like gold, out into a thin enough layer on glass, you can see through it.
Indeed. The same principle applies to titanium dioxide, which in any reasonable thickness makes a wonderful whitener, but which is also used as a thin film in alternating layers of high and low refractive index to form antireflective coatings, optical filters, heat reflecting windows, etc. Its very high refractive index suits it to all these purposes, including scattering when used in thick films so as to minimize absorption of the scattered light whence its bright whiteness.
If I may interject, the example of the solid state laser comes to mind, or more especially of the original solid ruby laser; radiation but not heat, though of course the end product was a special kind of radiation.
I think perhaps there was a paper by an Austrian about it in my grandfather’s time. What was his name? Albert something.
As for the sophism of heat for radiation, one admits to not understanding the cause of this confusion.
Bart, NiV was talking about opaque solids. Ruby is not opaque.
Vaughan Pratt
Nothing is opaque to all of everything, and even transparent things are opaque to some of some things.
Red ruby is somewhat opaque to some green light. Though NiV’s proposal above looks kinda fun, and may even be true.
Incandescence gives us another clue, in that even tungsten — quite opaque — will glow from within, at least if we tust our eyes.
Some photonic metamaterials (http://en.wikipedia.org/wiki/Photonic_metamaterial) exhibit fun surface emissive radiative effects (such as twelvefold increase in efficiency of old-fashioned lightbulbs http://www.azom.com/article.aspx?ArticleID=1538), however (see also http://wakalix.com/tech/PhDdissertationBrianTSchwartz.pdf) so you may be right and I remain agog for discussion of the surface/internal radiation model of exotic opaque solids.
I wouldn’t expect we’d need consider the case of the photon tree falling in the blackbody forest.
Red ruby is somewhat opaque to some green light.
Good point. NiV’s comment about radiation traveling a short distance in opaque solids takes two parameters, the solid and the wavelength. I imagine green photons can pass many thousands of ruby atoms before being captured, easily inferred from the transmission curve for ruby. So even green light in a ruby would not be as extreme as what NiV had in mind.
What I’d love to see is transmission curves for much more opaque objects, where a photon has a mean free path on the order of just a few atoms. There seems to be a lot less data in those cases.
Dear Dr. Curry:
I have another question for you: In Section 14.3, planetary energy balance, you have assumed that air is transparent to visible light. We know that this is an incorrect assumption. We see visible light absorption by the atmosphere every morning, afternoon, and sunset, without measurements. If you wish to measure it please do so, it does not cost a lot.
Therefore, you, incorrectly, assumed that the atmosphere is transparent to visible radiations; but, you also assumed that the atmospheric layers, or slabs, exchange radiations between them, which is inconsistent. You, in fact, crated a radiative effect out of the blue. This effect appears to be what is now called greenhouse gas effect. The effect can not be real for it is based on incorrect physics, it is fiction and does not exist in the real world applications.
Scattering isn’t absorption.
However 25% extinction most certainly is absorption.
Like i said, if you want a complicated radiative transfer model, look at the general circulation models. It is pointless for me to discuss this with you any further.
Dr. Curry:
Thank you for your time, and now I know that you referenced mother’s work.
Sorry, I meant others work.
Now that you have the link I hope you read it and return to say your mind was changed. or present an argument
NASA Science News for August 18, 2011
For the first time, a spacecraft far from Earth has turned and watched a solar storm engulf our planet. The movie, released today during a NASA press conference, has galvanized solar physicists, who say it could lead to important advances in space weather forecasting.
FULL STORY at
http://science.nasa.gov/science-news/science-at-nasa/2011/18aug_cmemovie/
Judith,
It appears that there is an error here. Your text would continue logically, if the value of e is taken as the inverse of that given by the definition.
oops thanks for catching the typo, its fixed.
Judy: You attribute the difference between 254 and 288 to radiation, but this is not correct scince it results from an interaction between thermodynamics and radiation. An interaction in which doubling of CO2 cannot be argued to have other than a small effect on global temp, less than plus/minus 0.3 C. Why do you mislead by forgetting thermodynamics?
PS Postma’s model is not mine.
Claes, a zero dimensional model that includes only radiation tells you only about radiation. The actual interpretation of the effective radiating temperature requires thermodynamics (the effective height of the effective radiating temperature depends on thermodynamics). So the point of my post is that for e ~1, you need a more complicated model to interpret all this in any detail. And I’ve provided a whole list of more complicated models to use. Bottom line: the existence of the greenhouse effect is demonstrated by the observed infrared spectra, and its interpretation by the physics that goes into radiative transfer codes. The zero-dimensional model is not used to determine the magnitude of the greenhouse effect, nor can it be used to deny the existence of the greenhouse effect. in the context of comparative planetology, it does support the existence of the greenhouse effect.
Are we any closer to the goal?
Can we ever get closer?
If it is an actual disagreement, as opposed to a misunderstanding, then the goal is misstated. Nor are a few lines from a textbook likely to resolve the disagreement. In The Structure of Scientific Revolutions, Kuhn describes how proponents of conflicting paradigms often talk past one another. They cannot seem to come to grips with their differences. We may have here a classic case of this deep confusion. (I did my doctoral thesis on this problem, formulating a new theory of scientific language in the process.)
Again David, you’re supposing that your ‘expertise’ in issue analysis can supplant real technical expertise in physics. This is fallacious reasoning given the fact that Miskolczi, Johnson and Postma offer no other ‘paradigm’ in place of quantum mechanics, on which all of the physics that leads to the GHE is based.
So there is no issue related to how I, Pekka or Judy ‘come to grips with their differences…’ because there are no ‘differences’ other than these other ‘theories’ being incorrect.
Maybe you can’t see that because you lack technical expertise, but you shouldn’t confuse your lack of understanding with the existence a of real ‘issue’. Unless these guys predict observables in a particular quantum mechanics experiment, it’s all garbage.
maxwell
Miskolczi was employed by NASA as a theoretical physicist
Johnson and Postma are certainly well educated enough to form opinions with sound reasons for doing so.
You are almost claiming infallibility for proponents of the Greenhouse Theory
Bryan,
I’m not claiming the infallibility of anything. I’m saying that there is clear observational evidence that proves the theories presented by the ‘researchers’ named above as totally and utterly incorrect. There is no way around this fact, which is why each of them makes such an enormous deal about the way that specific equations are derived or code is written.
As I have said before, I have no doubt that these particular men can do math correctly, but when applied to physics, there is nothing but failure so far. I would go into greater detail of this observational evidence, but it’s found elsewhere I’ve written it and your combative attitude on other threads leads me to believe that it would be a futile attempt at educating.
So go on believing whatever you’d like. The physics of real world could care less.
Maxwell says
….”So go on believing whatever you’d like. The physics of real world could care less.”….
There is a growing number of well qualified mathematicians and scientists(particularly physicists) who have grave doubts about about the AGW story.
The list runs into several thousand.
If you are such an expert why don’t you stick to pointing out the flaws of (lets say) Postma.
Instead you come across as wanting to stop dialog!
My rejoinder to your quote at top is;
….”So go on sticking your head in the sand. The physics of real world could not care less.”….
Bryan,
How can my head be in the sand while I’m standing at the front lines of science challenging currently held theories?
I’m actually doing what Claes, Miskolczi and Postma trying to do, but I’m at least trying to use correct physics to do it. Making predictions that are testable and then re-assessing my theoretical contributions as the results come in.
I’ll be honest. I’m more wrong than right, but I am also willing to acknowledge I’m wrong and fix the problems. We have seen no such behavior of any of three researchers whose work has been featured here and elsewhere. They change their story, refuse to answer to serious concerns or will simply stop engaging in a conversation with particular contributors, as has become the case between Claes and myself.
If anyone is sticking their head in the sand it’s these three guys. No criticism is worthy of note nor are the standard accepted physical interpretations of the real world.
The stubbornness they display is noteworthy only for it’s amazing fortitude and little else at this point.
Moreover, it seems rather ludicrous to me, and maybe others who have witnessed the exchanges, that you should claim I’m trying to stifle dialog. There are extensive comments in which I was totally engaged with Claes, as well as others, from months ago. Without looking at this conversations, your point is moot.
And when I made my points, Claes just put his fingers in his ears, as he did with the criticisms from other contributors.
So he’s been stifling dialog. Go look at the comments. Rather than clearly explaining the meaning of his theory, he resorts to poorly thought out analogies and improperly done calculus. One cannot reason with on these points. I’ve tried for going on a year now.
So again, rather than trying to figure out what the correct context is in this conversation, you’ve assumed that you’ve seen all that is to be seen and accounted for, despite the fact that you clearly have not. Please start at the beginning of the Dragon’s Slayers threads here on this blog, read all the comments (more than 5000 at this point I would presume) and then come back and talk to me.
I’ve now put in a great deal of effort trying to talk about meaningful physics with a group of people dead set on denying well documented and understood physical law (all from quantum mechanics, mind you) in order to maintain a specific position about global warming. When they continue to ignore my attempts, why should I continue to engage with them?
‘Insanity is repeating the same thing over and over again and expecting the different results.’
What’s with this Claes character? I paged through his huge opus on applied math called “Body and Soul” and haven’t a clue as to what he intended to accomplish with it. (other than to use it as an example of his being constantly misunderstood :)
Maxwell, what you are ignoring is the hundreds of articulate responses these folks have given to the criticisms and arguments against them. Claiming there is no issue here is unrealistic.
David,
You are unbelievable. Do you really believe that there was anything of value in their responses?
That’s the problem that I and many scientists have with philosophers of science. They think often that their formal thinking can supersede scientific knowledge.
Pekka, you guys convince me altogether on the physics. But the sensitivity issue remains unresolved and I don’t trust the accuracy of models in principle. So where are we?
As I’m a physicist, not a climate scientist, I have personal understanding only to a point. Essentially I trust in my understanding of the idealized models that explain the general physics and structure of the atmosphere, a typical strength of the GHE (not exactly that of the real Earth, but something similar), the radiative forcing, and the non-feedback climate sensitivity (although I don’t really like the concept).
Going beyond that I’m a layman with some ability to make educated judgments on how far I should trust, what working climate scientists tell.
(I’m also a systems scientist with fair research level knowledge on modeling and on some fields of economics. I was physicist first, the other expertize is more recent. And one more point. I have worked very much with engineers, and I have taught university level engineering students.)
David,
‘…what you are ignoring is the hundreds of articulate responses these folks have given to the criticisms and arguments against them.’
That’s exactly it. You have such a complete lack of technical knowledge in physics and physical science that you are easily confused between the totally nonsensical arguments that have been proposed to criticism and ‘articulate responses’.
For Johnson to say that his theory ‘comes from Maxwell’s equations’ was the most I could get him to say to me with respect to the actual physics behind his theory. To the untrained eye, like yours, that may seem ‘articulate’ (although I think my chihuahua would see through it). To me, the trained optical physicist, such a statement is totally nonsensical. Of course he used Maxwell’s equations. He’s deriving dynamics of radiation. If he didn’t use those equations (and I’m still not sure how he’s using them), then his theory would be even more incorrect.
But there is more important point. You have several times in these threads asked for observational evidence of the incorrectness of these theories to which several commenters, including myself, have provided ample evidence to show. Yet you still want to claim that there is an ‘issue’ here. It’s total ridiculous.
And here’s what you told Pekka on a thread just recently,
‘Perhaps you should stick to physics and leave communication theory to the experts.’
yet, you are constantly insisting that as a non-expert in physics, you can include yourself in a discussion as what is and what is not relevant in terms of the physical theory of the greenhouse effect.
So physicists should stay out of communication theory, yet a communication theorist should be allowed to do physics?
It’s this kind of backward reasoning that is going to marginalize your opinion on these and other topics on this blog in the time ahead of us. Although you still have time to change course.
David said:
I get that criticism as well. According to some people, everything you write needs a Carl Sagan version to complement the scholarly work. If you can’t write like Carl Sagan, they expect you to hire a writer. Yet they don’t realize that the ghost-writer has to be able to understand what you have written and communicate it without distorting the meaning.
The reality is that share the knowledge with other scientists to the best of your ability and we will work it out.
You are ignoring the context. Pekka was propounding a theory of communication that did not work.
Maxwell, your disdain for my science does not impress me. I don’t want to do any physics. I just want to map the statements to see the lines of argument, or rather I am pointing out that they are mappable. I don’t have the money to do the mapping. .Something you clearly do not understand. In fact if I did map the issue tree you would be able to point to the specific errors you claim they are making.
David,
‘…your disdain for my science does not impress me.’
What science? Philosophy is not science. Knowledge mapping is not science. ‘Issue analysis’ is not science.
Let’s be clear.
I think that what you do has importance. I’m not diminishing the value of your expertise or its necessity in the appropriate context.
But the question still remains whether you have the appropriate expertise to be able to to say that there is a real technical debate going on between the proponents of the standard understanding of the GHE and the ‘dragons’. Based your responses so far, my assessment as someone who has explicit expertise in molecular, optical and chemical physics, is that you do not have the requisite expertise.
To say something along the lines that I have ignored the ‘articulate responses’ of the ‘slayers’ is enough for me to know that you are vastly out of your league in technical knowledge for your ‘mapping’ to be any importance. I agree that would be able to find where the errors were in such a mapping, but it would a vast waste of your and my time to even get to that level of development. There is nothing of physical value contained in what Johnson or Postma have offered so far. Their complete lack of engagement with contributors here, including myself, makes me believe that there is no hope for such engagement.
As for your quote, I understood the context quite well. Pekka was making a point concerning the quality of communication of a contributor’s thesis which you were having a hard time understanding. Based on that fact, you thought it would suit your position to appeal to your own authority, which I do not see as an issue in that context.
In the same vein, I am appealing to my own authority in the realm of physical science and explicitly telling you that there is no ‘talking past’, ‘revolution’ or ‘ungraspable differences’ between my interpretation of extremely well understood physical law and that of Johnson and Postma. They are simply mistaken in their theories.
End of story.
Yet again, I feel that you should strongly consider accepting this notion as fact at this point or go ahead and learn the actual physics yourself at the level to which I am capable of discussing it in order to prove me wrong.
If not, then what is your point? That one can make a good argument with incorrect physics? Is that a point worth making here?
I’m sorry but I havent seen any articulate responses from them. I have seen changing the argument, ignoring the criticism, answering the wrong question, failure to clearly articulate testable predictions from their “theories”. The Slayers engage in “gainsaying’ not dialog. That’s clear. That you don’t see it is puzzling.
Mosh, the kind of reasoning moves you are talking about are not what I mean by articulate. I just mean well formed sentences making points of obvious substance. Note that whether they are true or false is irrelevant as far as building the issue tree is concerned. Moreover, a lot of what you describe sounds exactly like talking past.
I’ll deny that they make points of obvious substance. I am 112 feet tall.
is well formed, and appears to make a point that is obvious, but it’s missing something. It lacks warrant.
I think the tree works fine for understanding a conversation where good faith is practiced. This is not one of these cases. You either have people who are 112 feet tall, deluded, willfully ignorant, lying, or come up with your own explantion
Maxwell, Good point. I see it as people that try to orchestrate the analysis so that it meets the goals that they want to achieve. The beauty in real citizen-based science is taking the theory and the data and analyzing it and then seeing where it takes you. It could reveal new ways of thinking, it could lead to new inventions, or it could lead to you completely changing your original mindset. Scientific thinking is always about keeping an open mind.
My fledglings keep falling out of their nests. I’ll re-post:
Well, here’s an interesting juxtaposition:
and
David,
Do you believe in full relativism in natural sciences?
Pekka, Does full relativism mean there are no rational reasons to believe in one theory versus another? Or does it mean that one’s understanding depends on the context on the person’s worldview? Or is it something else?
The first sentence on relativism in Wiki tells essentially, what I had in mind:
I didn’t have in mind any deep philosophical analysis, just a loose interpretation of such formulations as implying that anybody’s subjective view is of equal value in judging what’s true physics.
Pekka
Thanks for raising that issue. Such relativism is directly contrary to the scientific method which requires observable evidence against which models can be objectively evaluated.
It’s thought provoking to notice, which participants in the discussion of this site are most eager to write messages about the scientific method, and how it should be interpreted and applied.
Unfortunately that happens almost exclusively with the aim of discrediting valid science based on ignorance on, how good science is really done and shall be done. Only in exceptional cases is the issue raised in connection with real problems in scientific practices.
Pekka, probably not although I do not know what you mean by relativism, much less full relativism. I am certainly not claiming that the dragons are right, or that nobody is right (which is what relativism sometimes means). I take no position on who is right because I have not tried to follow the physics.
I am a logician and my points have to do with the form of the argument. Logic is not about truth, it is about form, specifically the forms that reasoning may take. I have spent the last 40 years studying, diagnosing and resolving confusions, so I am telling you what I see going on here.
By way of background, my training is in analytical philosophy. Analytical refers to concept analysis. The original idea, developed a hundred years ago by Russell, Wittgenstein, and many others, was that the classic philosophical problems were conceptual confusions. What I discovered is that there are many conceptual confusions in ordinary discourse as well. So I became an applied concept analyst (probably because I was also an engineer), specializing on confusion in complex issues. I see things going on in this debate that you physicists don’t even know exist, because the logic of debate is not your field. (I have a diagnostic system of 126 kinds of confusion.)
David,
I have read a lot of philosophical literature, and know quite a bit of it, but it’s pointless to start to go deeper in that.
The point that I hold essential is that, when philosophical considerations lead to explicit conflict with substance knowledge, the error is in the erroneous application of philosophical ideas. That happens too often.
Pekka, first of all I am not advancing any philosophical considerations. Issue tree analysis is a science. Like word problems in algebra, I simply map relations between statements, relations that are already there. Second, if there is any conflict with substance knowledge in the slayer case it is in the statements, not the mapping. When I do an issue tree of a complex issue each side gets fair representation. That is the only way to find out what the issue is really all about, and where the confusions are.
Mind you, I am not doing an issue tree of the dragon slayer issues, because that would be a big job. But I have seen enough to see (based on 38 years of experience) that there is a genuine complex issue here, with many lines of internal reasoning and debate. The slayers may be wrong but they have one or more systematic ideas, and there is a lot of talking past going on.
I have a rule of thumb called the rule of 2000, which says that one has to work through an issue tree of at least 2000 statements to really grasp a complex issue. This rule clearly applies to the slayer issue. The interesting issue science question is whether it applies to each of the individual slayer arguments, or whether they have a unified position. I suspect the former, which adds greatly to the complexity.
However, I have found that no two issues have the same structure so I do not try to guess what it is going in. When I go into an organization that is suffering from confusion due to issue complexity it normally takes me a few months to figure out what the underlying problem or conflict is. And I usually need a subject matter expert to help me along the way.
David,
this is so much more simple than what it seems necessitates an ‘issue tree’.
Claes’ theory clearly predicts that 275 K radar dish detector cannot absorb radiation emitted by a blackbody at a temperature below 275 K. Yet, a radar dish detector can detect the cosmic microwave background radiation from the big bang itself. This corresponds to the blackbody emission of space at a temperature below 5 K.
So clearly Claes’ theory is wrong.
There are very similar clear points of contention between the predictions of both Postma’s and Miskolczi’s theories as well. There is no need to assess each and every one of their grammatically correct, yet physically nonsensical responses when these inconsistencies are pointed.
When are you going to grasp this point?
Algebraic arguments concerning logic don’t matter when physical reality dictates what is and what is not truth. That is the ultimate failure of logical arguments in this context. Observational evidence is a necessity, which seems to be the failing of your interpretation of this entire enterprise. Without the sufficient technical expertise to be able to assess the claims of these theories in light of well known physical observations, all of your points concerning issue analysis, trees or what have you are totally moot. They don’t matter in this context. There is nothing ‘complex’ happening.
Why are you struggling so mightily to grasp this point?
Have you even gone through the first two slayers threads? Have you actually looked at the concerns raised and inconsistencies point out?
But there is also a diagnostic system of intentionally misleading arguments (the list of fallacious arguments ) and then you have the scoring system for someone who is off the deep-end ( the crackpot index). These strategies are not borne by confusion but they come from human intent of various forms, including that of game theory. How do you account for these kinds of arguments?
IPCC seems to have employed a couple of these viz.
Argument From Adverse Consequences (Appeal To Fear, Scare Tactics):
Special Pleading (Stacking The Deck):
using the arguments that support your position, but ignoring or somehow disallowing the arguments against. This is also known as selection bias or cherry-picking.
Web & Gyp, indeed there is no lack of fallacies. In fact I spend a lot of time identifying them, as it is something logicians have done for several thousand years. Fallacies are certainly confusion causing factors, which is technically what my taxonomy of confusions lists. But I do not usually concern myself with intent, as that is psychology, which is not my field. I assume everyone is honest unless I have strong evidence otherwise, which occasionally happens.
I would point out that a lot of what you are talking about is advocacy. Advocacy, or making your best case, is not generally considered to be dishonest, as it is the basis of both our policy and our judicial systems.
David,
Curious why Postma links to Lyndon LaRouche, referring to him as an “American Patriot and polymath”, and then quotes him over a page in length, where LaRouche discusses Platonic ideals. This seems right up your alley, but I can’t make much sense of it.
Judy, you claim there is GHE referring to a model which only includes radiation and no thermodynamics, which you admit does not at all describe climate.
Yet you claim that the GHE you are describing is a climate GHE. Don’t you see that you are contradicting yourself? Or is your GHE not about climate?
Claes,
the major point has stated very clearly by Judy. The measured radiation in space emitted by the atmosphere corresponds to a greybody at 255 K. The surface, however, is 288 K. The greenhouse effect is the difference because it can theoretically explain the stratification of energy in the vertical and latitudinal directions VIA RADIATION. Part of how that stratification occurs is due to radiation and we can measure it to support the GHE theory as described by Judy in her text, which I would suggest as informative reading on the subject.
Furthermore, the actual measurement of the atmospheric radiation itself is a falsification of your theory as incorrect given that a warmer blackbody (a detector of some kind) is absorbing radiation from a cooler blackbody (the atmosphere).
So there you have it.
Everyone appears to missing the most obvious The question to be asked is this: If the earth had an atmosphere without CO2, what would the surface temperature be? How much of the 33C warming is due to H2O and how much is due to CO2?
CO2 contributes much less than H2O, so we ware looiing at a small fraction of 33C due to CO2. Maybe 5C? Now, as we know CO2 is a log contribution, how many doubling of CO2 are there in our current 400 ppm to give us this small fraction of 33C? Maybe 2 ^ 9 or more? So the contribution of each doubling of CO2, maybe 5/9 C max.
Which explains why temperatures have not increased significantly even as CO2 output has shot up like a rocket due to rapid industrialization in China and India.
Lacis et al. (2010) did a model study. The “Control knob” paper showed a reduction of nearly 35 C without CO2. This is because a lot of water froze out and increased the ice albedo too which added a positive feedback. Interesting experiment.
What would be the reduction without CO2 AND H2O?
About 35C, because w/o CO2 (and other non condensing GHGs, but mostly CO2) the GHE collapses and H2O disappears from the atmosphere. Just like Jim D said.
It is circular reasoning. It proved only that a model based on radiation and radiation forcing gets to those results in a flat world without night and day.
They used equations for dynamics and physics and time-integrated them in a low-resolution GCM.
In a flat world without night and day at double the distance from the sun. Sorry, we have past the flat world image for the earth, but some still hang to it.
Is that your model, or are you talking about Postma here?
I would be interested in Postma’s computation of the global annual average solar flux at the Earth’s surface. Until he does that, he is not talking in climate terms.
ferd,
I am not sure that I do know that the logarithmic relationship is thought to hold throughout the progression down to zero.
To do so with the knowledge that the current value is finite would imply that below some point the sign of the effect would reverse followed by a descent towards an infinitely negative value.
I do not think that this is the case and infer that at some point the nature of the curve may tend towards the linear and even something more swallow and approach zero just as the concentration approaches zero.
I could but speculate on the number of halvings that would approximate a logarithmic rule but I can but think that it is not unbounded.
Alex
The true point that is missed is that it is not gases but water in liquid and solid form i.e. clouds that provide well over 75% of the greenhouse effect.
Water ingaseous form combined with the effect from clouds provides well over 90% of tyhe greenhouse effect.
In the absence of CO2 clouds and watervapour could easily account for over 99% of the greenhouse effect but because when no cvlouds are present CO2 first takes its chunk out of the thermal radiation from the Earth over the band centred at 14.77microns providing about 10% of the greenhouse effect.
Essentially if there is enough food for ten people but an eleventh person comes to the table the same amount of food is consumed with each person consuming less. The same is true for the greenhouse effect; there is only a limited amount of the earth’s radiative energy captured by the atmosphere and if CO2 increases the only thing that changes is that clouds and water vapour trap less.
Any publication about the greenhouse effect on Earth that does not explicitly state that over 90% is from clouds and water vapour is scientifically fraudulent, because the named greenhouse gases in the Kyoto Accord with the exclusion of CO2 have a combined contribution to the greenhouse effect that is indistinguishable from zero!
I concur Norm.
Ignoring the ‘habits’ of the atmosphere (as a whole) and just taking note of the ‘habits’ of, so called, ‘long lived radiative gasses’ is like “throwing the baby out with the bath water”!
One can only observe (and ‘mark’) part of the observation. This can only lead to ‘obsfuscation by exclusion’.
Best regards, Ray.
Which explains why temperatures have not increased significantly even as CO2 output has shot up like a rocket due to rapid industrialization in China and India.
Fred, are you claiming you can see CO2 coming out of China and India that the observatory at Mauna Loa cannot? I would love to learn how to do this, are you willing to divulge your trick or is it a closely guarded secret?
CO2 shot up “like a rocket” between 1960 and 2000. In that period temperature climbed 0.5 °C. Looks like a strong correlation to me.
Judy, consider the difference between ‘doesn’t exist’ and ‘needn’t exist’. It is creating a strawman to claim Postma’s model is a claim of ‘doesn’t exist’. It’s merely speculating that the GHE need not exist. In my opinion, his effort lies somewhere in the class of information suggesting that the effect of CO2 has been exaggerated. Where in that class? Well, let me check the seating diagram. It’s early in the semester.
=========
Kim the way to go is to break the problem into pieces. Once we can get past the basics of infrared radiative transfer and the fact that the greenhouse effect exists and acts in the direction of warming the planet, then we can get to the more interesting questions like how does earth’s surface and atmosphere respond to this heating thermodynamically, and then integrate the radiation, thermodynamics and dynamics to try to understand the feedbacks.
So sure, w should all be skeptical of a high confidence in a 3C sensitivity to a doubling of CO2. But the reason for being skeptical about this number should be in the complexity of the coupled thermodynamics and dynamics, not the basic radiative transfer of the clear sky greenhouse effect.
Oh, yes, I understand. It seems that Postma’s effort has focussed attention on the inadequacy of the ‘coupled thermodynamics and dynamics’ more so than the basic greenhouse effect. In the conversation, more attention was placed on arguing about the greenhouse effect’s existence, which is, as I say, a strawman. That Postma’s work could imply no greenhouse effect doesn’t mean that it does and I don’t think that it does.
So can we get on with the ‘coupled thermodynamics and dynamics’? That is where it is all at, and we all know it.
I think I’ve never heard so loud
The quiet message in a cloud.
============
Hmmm.
Well, we have this:
And we have this:
Along with this:
And we also have this:
Along with this:
And The Magic 8 ball says: “Situation somewhat murky.”
Careful there, kiim. You wouldn’t want to be winnowing, would you?
Joshua, you emphasize ‘is not likely what actually exists.’ I emphasize ‘as we understand it today’. You want to spin it back to the existence or not of GHE, I want to spin it to today’s understanding.
I applaud your interest in the science. I can’t help but believe it will help you a lot.
===============
Getting into the highly nonlinear, coupled thermodynamics, which as you say is where the real analysis is, is so far above Joshua’s and several others heads that they MUST keep bringing the conversation back to a simple concept that they can continue to pretend tells the whole story. Otherwise they might have to admit that the “science isn’t settled”, and that would never do.
Bruce too
It’s the natural reflex of a mathematician when discovering an error in another’s work to resort to first principles to explain the source of the error.
I have no way of ascertaining the mathematical aptitude of any commentator on this blog; other than to suggest locking them in a room with Chief Hydrologist and asking them to derive a solution for any of the unsolved classic problems of mathematics, and time how long before they pick the lock and escape.
I do know, however, that glaring errors pop up repeatedly in this discourse, and I have far greater regard for those who see the errors when they’re explained, struggle through reworking their computations, and move on to accept ideas based on correct logic than for those who keep insisting that because their conclusion must be right, the error cannot be there, or it cannot affect the outcome.
‘Would they take to Rebelasian ‘disciplination’?
Chapter 1.XXIII.—How Gargantua was instructed by Ponocrates, and in such sort disciplinated, that he lost not one hour of the day.
‘Afterwards he put himself into such a road and way of studying, that he lost not any one hour in the day, but employed all his time in learning and honest knowledge. Gargantua awaked, then, about four o’clock in the morning. Whilst they were in rubbing of him, there was read unto him some chapter of the holy Scripture aloud and clearly, with a pronunciation fit for the matter, and hereunto was appointed a young page born in Basche, named Anagnostes. According to the purpose and argument of that lesson, he oftentimes gave himself to worship, adore, pray, and send up his supplications to that good God, whose Word did show his majesty and marvellous judgment. Then went he unto the secret places to make excretion of his natural digestions. There his master repeated what had been read, expounding unto him the most obscure and difficult points. In returning, they considered the face of the sky, if it was such as they had observed it the night before, and into what signs the sun was entering, as also the moon for that day. This done, he was apparelled, combed, curled, trimmed, and perfumed, during which time they repeated to him the lessons of the day before. He himself said them by heart, and upon them would ground some practical cases concerning the estate of man, which he would prosecute sometimes two or three hours, but ordinarily they ceased as soon as he was fully clothed. Then for three good hours he had a lecture read unto him. This done they went forth, still conferring of the substance of the lecture, either unto a field near the university called the Brack, or unto the meadows, where they played at the ball, the long-tennis, and at the piletrigone (which is a play wherein we throw a triangular piece of iron at a ring, to pass it), most gallantly exercising their bodies, as formerly they had done their minds. All their play was but in liberty, for they left off when they pleased, and that was commonly when they did sweat over all their body, or were otherwise weary. Then were they very well wiped and rubbed, shifted their shirts, and, walking soberly, went to see if dinner was ready. Whilst they stayed for that, they did clearly and eloquently pronounce some sentences that they had retained of the lecture. In the meantime Master Appetite came, and then very orderly sat they down at table. At the beginning of the meal there was read some pleasant history of the warlike actions of former times, until he had taken a glass of wine. Then, if they thought good, they continued reading, or began to discourse merrily together; speaking first of the virtue, propriety, efficacy, and nature of all that was served in at the table; of bread, of wine, of water, of salt, of fleshes, fishes, fruits, herbs, roots, and of their dressing.’
http://www.gutenberg.org/files/1200/1200-h/p1.htm#2HCH0005
I feel your pain! If you follow this discourse as much as I do, you should have a very low regard for the likes of say, um ……Michael Mann and his apologists. He used (deliberately?) data in his 2008 paper from a Finnish scientist (Tiljander) that was upside down from what the data actually said. When this is pointed out to them, they categorically refuse to acknowledge the error, even going so far as to say the claim is bizarre! And we have a president that actually listens to him!!!
Interesting times.
Bruce too
Oh, you mean http://arthur.shumwaysmith.com/life/content/wheres_the_fraud vs http://www.bloomberg.com/news/2011-08-22/climate-change-scientist-cleared-in-u-s-data-altering-inquiry.html?
There we get into the murky distinctions between vindication in the face of persecution, fighting the good fight, going down with the ship or blindly holding to wrong ideas.
Let’s look at Joachim Seifert (who has been extremely patient with me); his thesis on the degenerate elliptic motion of the planet (libration) and coincidental paleoclimate is interesting, and he is very confident he is right.
Is JS right? Wrong? Dunno.
Were JS faced with such an outpouring of condemnation as MM over the past 3 years, would he fold under pressure, or carry on, as MM has done up to his most recent of several substantial vindicating events?
Dunno.
So, with all the murk, can’t say I’m in position to declare glaring error per Mann re Tiljander, unless I’m willing to spend a lot of time researching the matter in the hopes I see something everyone else has missed.
A far cry from what I
Bart R
Had not noticed your reply since it was off margin.
I guess I should not waste any more of either one of ours’ time. I read the lame articles that you linked to. They are the same old insane denial of facts that alarmists can’t stomach. For all the long winded tripe in the first one, it never did directly answer whether or not Mann used polluted data and whether he inverted the data (that showed cooling not warming). Just lots of red herrings to change the subject in order to prevent having to answer as simple a question as can be asked. ie Did he use data that Tiljander said was corrupted and should not to be used. ie Did he then use the data inverted? The answer to both questions is yes. I put a ? after deliberately in my first post. I only strongly suspect he did it deliberately. But there are people in prison for less proof than this.
As to the second article pointing out that all the Climategate guys are lily white, well as our host, and many other scientists (the British IOP ie) have said, the inquiries were nothing but whitewashes. Dr. Curry likened it to the fire department being told that there is a fire in the kitchen of a house, only to have them say that they looked and found no fire in the living room. Very funny I thought.
Bye
Dr. Curry likened it to the fire department being told that there is a fire in the kitchen of a house, only to have them say that they looked and found no fire in the living room. Very funny I thought.
My experience with analogies is that they only work on the choir. Evangelists are better served by recruiting would-be converts to the choir by appealing to their love of singing. A few hymns serve to turn off the choir’s critical faculties, thereby putting them in a state to receive an analogy as though it were just another hymn.
My two cents on the function of church services. Which I’m all for as long as they’re kept to once a week.
Bruce too
Perhaps having felt the intention of my words were twisted by your use of them sours me on trusting the interpretation you give the interpretation of the words of others, but I feel strongly warned to take what you say not at face value.
As President George W. Bush said, “There’s an old saying in Tennessee — I know it’s in Texas, probably in Tennessee — that says, fool me once, shame on — uh — shame on you. Fool me — uh.. uhm.. uh.. — You can’t get fooled again. ”
I don’t know what Tiljander said, and can’t be bothered to look it up and guess which event and context you might mean when you make your remarks. Implicit in your statements is a requirement of trust by the reader which, yes, is a waste of both our times.
I don’t pretend to know the truth of this Tiljander-Mann controversy, however the opinions you have expressed have only rhetorical merit, and so one can see why links to reports of fact or discussions involving reasoned dialogue and debate would be lame by your calculation.
Paleoclimatology has extraordinarily low resolution and is doomed to frequently provide contrary-seeming and moot evidence, at best indicating a wide error range and significant uncertainty.
It tells us that anything we wish to say about global climate before the modern age of instrumentation is so limited that we ought treat such expressions as “Little Ice Age” and “Medieval Warming Period” as the feeblest indicators, and we ought learn utmost respect for the doubts we ought harbor as skeptics about claims on climate in general.
So while I respect that paleoclimatology provides us this much perspective, and narrows down the probable ranges of expected climate values over the spans of time prior to this quarter millennium, I see zero reason to find it so exciting as yourself and many commentators do.
These tempests are marginal scandals and infinitessimal tempests in a tiny teacup, and not interesting enough to warrant multiple taxpayer-funded inquiries that all appear to come to the same conclusion, by my admittedly minority point of view.
But as they _have_ had multiple quasijudicial proceedings, and those proceedings have been concluded with fairly consistent agreement on the points you’re finding contentious, I have to ask, how is this not just sour grapes on your part?
If you disagree with a finding to the point you have to allege incompetence on the scale of firefighters going to the wrong room and missing the fire — or is it corruption or deceit you accuse all of these official investigations of? — then shouldn’t you as a reasonable person seek every measure of appeal or overthrow, instead of just blogging defamations about it bitterly?
Me, I believe it’s not worth my time, as the interesting part of this topic isn’t the paleo record, which is principally useful for squashing the intellectual insects who spout LIA-this and MWP-that like bible-thumping pulpit bullies chasing down a Darwinian.
“Paleoclimatology has extraordinarily low resolution and is doomed to frequently provide contrary-seeming and moot evidence, at best indicating a wide error range and significant uncertainty.
It tells us that anything we wish to say about global climate before the modern age of instrumentation is so limited that we ought treat such expressions as “Little Ice Age” and “Medieval Warming Period” as the feeblest indicators, and we ought learn utmost respect for the doubts we ought harbor as skeptics about claims on climate in general.”
If you are pretending you can measure average temperature in in terms of tenths of degrees hundreds or thousands of years ago, whereas we can’t even really measure tenths of degree in terms of average temperature currently. There are problems.
There are similar problems when you imagine you able to accurately measure the PPM of global CO2 from Ice cores of the past. You can’t accurately measure current level of CO2 by examining new ice.
But if you measuring a order magnitude greater, such 1 degree C rather than a 1/10th of C. Or if you are measuring hundreds of PPM of CO2, instead two hundred, fifty two PPM, at this resolution one can get accurate data.
From Paleoclimatology we can determine that global temperatures of the Little Ice Age were about 2 C cooler than present temperatures. We can’t know if it was 2.13 C cooler or 2.1 cooler. Or that the range was 1.8 to 3.1 C cooler. But the time period of Little Ice Age is “known” because it marks a period global glaciers advancement and ended with glaciers globally receding. You can date the ice in glaciers. There is a lot science related to this. There is little to doubt about this.
Paleoclimatology also indicates that “Medieval Warming Period” was centuries in length and generally as warm or warmer than the present temperatures.
gbaikie
I’d be delighted to read details of your supporting evidence and the independently audited statistical analyses substantiating your claims.
Do you have links?
Judy,
You avoided the spirit of dispassionate scientific inquiry from the start because you refuse to accept that Postma has demonstrated that the numbers add up with or without factoring in a GHE.
The first half of his paper systematically lays out the standard GHE and the numbers and equations involved. He then then uses such numbers when he re-thinks the model paradigm and adds into the equation the ACTUAL insolation numbers from measuring the energy inputs of night and day.
His approach is CLOSER to reality than the standard GHE model because that OMITS the existence of the inertia for such insolation due to the difference in day/night – plus Postma also includes adiabatic physics. He thus shows that making Earth into a flat disk under 24-hour twilight causes the GHE model to be 33K short in the overall known energy budget.
He shows that the disparity is a product of the failure in averaging insolation. The definition of an average means you have both higher and lower numbers…simple laws of physics such as the adiabatic distribution tell you that the warm number should be found at the bottom, the cool ones higher up. It all adds together to show how the “average” can be properly calculated to balance with the incoming energy and thus demonstrate we do not need to rely on a mythical GHE of +33k.
His point is we need to look for the true average from the DEPTH of the atmosphere not at the ground surface. He argues this is where average is *always* found – it is in the middle…no matter what the input forcing is. So if the input forcing is -18C and this is therefore supposed to be the average temperature of the system, a-priori you should not expect to find that at the surface, but in the middle, and the surface-gas will be hotter, all without a GHE in the first place.
This is the only way we can reasonably considering -18C as an average input figure…with these caveats acknowledged and understood. Otherwise you need to consider the instantaneous inputs and work your way back to the daily average…you learn a lot more physics doing it this way anyway. The “averaging” route appears to have made many people go insane and seemingly forget what the averaging was *about* in the first place.
One cannot have a proper scientific discussion about the greenhouse effect without a proper scientific definition. The discussion taking place is everyone arguing over an effect that does not actually exist but is merely a theoretical number for how much cooler a planet would be if the atmosphere was removed.
On Mars this is 5.5°C on Venus this is 450°C on mercury which has virtually zero atmosphere this is just a tiny fraction of a degree C
On Earth this is stated between 33°C and 35°C depending on how the calculation is done and the rounding involved.
The entire AGW hypothesis is based on turning tghis theoretical number into an active process and then falsely attributing the entire process to fraudulently coined greenhouise gases which have no valid scientific definition.
The simple truth is that water vapour and clouds account for well over 90% of this effect so by default CO2 at current concentration can account for no more than 10% of the 33°C. If CO2 concentration were to double all that would happen is that less of the effect would be due to water vapour and clouds and more would be due to CO2 but the net effect would still be the same 33°C.
The monly thing that could change the value of the greenhouse effect is a change to the Earth’s temperature. If the Earth’s surface was hotter there would be more radiation and the same insulating effect of the atmosphere would produce a larger theoretical temperature differential also known as the greenhouse effect.
Norm
I’m with you right up to the word ‘simple’, where I believe you may wish to avail yourself of a dictionary. ;)
Your 90%, is it the top 90%, or the bottom 90%?
Is it an independent figure, or does it vary with the dependent variable no more than 10%?
You assert without explaining a pure negative feedback of CO2 and H2O effects that, apparently, is coincidentally also exactly equal in size for Temperature despite the many differences of the two molecules.
Or do you? Your last sentence seems at odds with the paragraph it ends.
One wishes to understand, how did you derive this wondrous function, unless you mean its opposite?
If CO2 concentration were to double all that would happen is that less of the effect would be due to water vapour and clouds and more would be due to CO2 but the net effect would still be the same 33°C.
Fail.
Like most of the world you assume that the warming effect of GHGs is linear in their level. If you would redo your calculations using the correct law, which is logarithmic, you would have a better chance of arriving at a reasonable estimate of the impact of GHGs.
JC says: “Once we can get past the basics of infrared radiative transfer…”
That could be part of the problem. DavidN on another post indicates that
the following are equal, SB(T1^4-T2^4)= SB(T1^4) – SB(T2^4)
Do you think they are equal in radiative heat transfer?
I donot.
Do you realize what you’re saying? You need to go back and review elementary algebra.
I do know what I am saying. Is that the way you do radiative heat transfer?
You have just pointed out a problem in the discussions. There are no radiative heat transfer equations that use the right hand side of the = sign. And why would that be? Because you must first have a temperature grdient and the only way to do that is with the left side.
Path and gradient are the basics and DavidN you cannot manipulate the temperature until you’ve established the gradient. Algrebra or not.
The left and right hand side are equivalent statements. They say the same thing and return the same answer, everywhere. Maybe the reason you don’t see the expression in the right hand form a lot is because the left hand form is a trivial simplification that requires fewer symbols, a simplification that every high school algebra student knows.
The expression you gave, in either form, contains a temperature difference. I don’t believe the expression is useful in terms of a temperature gradient, becuase the blackbody surface is an idealized surface at the discontinuity between two regions with different optical properties, not a surface within a single medium.
David N,
But it’s more than plain algebra, it’s a formula. The concept is not that hard if you think of synergy and emergence – the sum is greater than the parts type thing.
Nonsense. The formula y = c(x1 – x0) is the same formula as y = cx1 – cx0. Plug in any numbers you want.
But “SB” is shorthand for the entire Stephan-Bolzmann function; it is not a constant.
Please express SB as a function of T, with references, or accept that SB = σ, known as the Stefan-Boltzmann constant.
As I said DavidN you have just shown the first and maybe the largest problem. Doing proper radiative heat transfer equations. Once we start buggering up the language then the equations and what is next. If we cannot agree on the proper equations to use then all is lost in discussions.
Path and gradient and you choose not to find the gradient. How sad.
You have not offered any different equations, you’ve only asserted that the same equation written two ways is somehow different, which is absurd.
The SB Law is defined on a surface with a discontinuity. It’s not a vector formula. A gradient is typically defined over a continuous vector function.
Instead of making vague reference to “buggering” things up and offering no actual content in your alternative viewpoint why don’t you respond at a equal level of sophistication, define your terms and submit your equations.
That’s only true in an operation-preserving isomorphism
Like an operation say, multiplying T^4 times a constant?
For some reason mkelly and Kermit seem to think that SB(x) is some sort of function applied to x, instead of merely multiplying the Stefan-Boltzmann constant by x. I would be fascinated to know what textbook this appears in.
Meanwhile I think I understand the confusion. The phrase “Stefan-Boltzmann” is being applied both to the dependence of power density on temperature and to its associated constant σ = 5.670400 x 10^-8. The former has the form σT^4, which denotes the product of σ and T^4. Anyone who thinks the Stefan-Boltzmann function denotes something else is kindly invited to step forward and explain what they think it denotes and why.
You did not answer my question Judy, an essential question: Is the GHE you know exists a GHE about climate? I think your readers expect an answer.
At this point Claes, if you don’t know the answer to this question, you should give up. Dr. Curry has made it crystal clear that she thinks that radiation plays a role in maintaining a higher level of energy at the surface of the earth than at the top of the earth’s atmosphere.
What more is she to do? Enroll you in the earth sciences program at Georgia Tech for a masters degree?
If you don’t understand the basic physical concepts involved and how they relate to Dr. Curry’s (or anyone else’) explanation of the greenhouse effect, I believe there is no hope for you. You’re already too far down the rabbit hole.
This exchange looks like a fine example of talking past. There is no obvious relation between Maxwell’s response about radiation and Claes’s question about climate. Thus Maxwell must be interpreting Claes’s question, probably in a way that Claes would not agree with. In science, concepts have theories built into them. People who hold conflicting theories have conflicting concepts of the same thing, so they will interpret the same sentences differently.
No, Claes will interpret anything said in a way that works for him only. And if he can’t interpret it at all (e.g. the entire discipline of statistical mechanics), then it’s bunk and you’re not allowed to use that part of science to argue with him. This last question doesn’t even make sense. Claes should explain the difference between a “climate GHE” and a non-climate GHE if he expects any kind of answer.
I agree the term “climate GHE” is unexplained, although he may have explained it earlier, which the phrasing suggests. The obvious thin to do when someone uses a term that is not understood it to ask what it means, but that sort of reasoning seems in short supply here.
As for the rest, your extreme claims are diagnostic for talking past due to conceptual confusion.
It’s not an extreme claim, it’s the truth. Go find the threads from 6 months ago, or just ask Claes today what he thinks of statistical mechanics.
David,
‘This exchange looks like a fine example of talking past.’
…yes, to you, the untrained non-expert in physics. Where was your take on my ongoing exchange with Claes when I explicitly pointed out that his violated the conservation of energy? Or that I pointed out I could easily calculate the response of the atmosphere, radiative and non-radiative, via the Maxwell-Bloch equations?
I have been having a conversation with Claes for 8 or 9 months now pointing out the enormous physical flaws with his theory. They are clearly documented on this and his own blog.
And you say,
‘Thus Maxwell must be interpreting Claes’s question, probably in a way that Claes would not agree with.’
The onus is not on me to correctly interpret Claes’ question. I know what is physically relevant in this context. The onus is on Claes to correctly predict what we clearly observe in reality, which his theory cannot do at this point.
So again, your lack of expert training in the context of the physics important to this discussion, as well as your lack of context in the actual conversation has misled to believe that there is ‘talking past’ by me. If there is any ‘talking past’, it clearly on the side of Claes.
You should be beginning to make better mental notes of these facts.
I think you are talking past david. he clearly wants to talk about talking past which is his speciality. So for him these discussions have to appear to fit into his system of understanding confusion. However, I wonder if Davids system has a mechanism for understanding deception. for understanding willful IGNORANCE. willful ignorance often looks like confusion, but it’s not.
People have a variety of reasons why they throw their hat into the ring and have different priorities driving their approach. The self delusion of belief in ones own perfect objectivity can easily lead to a belief in the wilful ignorance of others. Nobody has a perfect and fully developed theory of climate. The gap between pure physics and the application of physical laws everyone agrees and the complex systems we have imperfectly conceptualized and measured for a short period is such that disagreements about how those physical laws should be applied are inevitable.
In that situation, those more convinced of the correctness of their approach might come to the conclusion that others who disagree with them are being wilfully ignorant. I suggest that given the uncertainties, we should strive to avoid such *assumptions* and maintain an open and civil discourse using the presumption of good faith.
This is a pragmatic suggestion rather than a theory of disagreement.
TB,
I would agree with you if we were discussing internal variations of the climate system and analysis with which we would tease out those contributions from the overall behavior of climate.
But the slayers are not discussing those points. They are proposing that long held, experimentally verified and extremely well understood physical law is incorrect. They do this with poor math, poor physical assumptions and the backing of publishers totally impervious to criticism of any kind.
I cannot be pragmatic if after 8 or 9 months of continuing to engage in a meaningful physical discussion on these topics these same ‘researchers’ are saying the exact same bogus unphysical answers.
What is there even to be pragmatic about at this juncture?
Claes believes that an IR thermometer cannot read the temperature of the atmosphere because it can’t absorb the radiation emitted by the atmosphere via his theory.
That’s clearly wrong.
Postma somehow can tell the difference between a ‘physical’ response and an ‘optical’ response, nor does he understand that climate is not an instantaneous response of the earth system.
When going over the simplest points concerning time averaging to understand climatic change (change in the earth system over decades), he began an argument over who understood the concept of a Watt.
Really?
What more is there to do then to say that these men are willing to delude themselves in thinking obviously physically incorrect things? When someone is to say that a blackbody, which my definition absorbs ALL frequencies of light, will stop absorbing some frequencies because of the presence of a cooler blackbody it is not physically connected to, there is nothing to be pragmatic about.
I’m sorry.
Now you’re being wilfully disingenuous.
“What more is there to do then to say that these men are willing to delude themselves in thinking obviously physically incorrect things?”
Well, we could say that although your judgement is that of an expert in physics, your abilities as a psychologist may be in doubt. ;)
“I’m sorry.”
Accepted, and your frustration will be considered to be a mitigating circumstance. :)
mosher,
whether the ignorance is willful or not is meaningless to me. The point is that there is ignorance on the part of slayers as to what are and what are not important physical concepts, constructs and laws that necessitate critical analysis with respect to science behind global warming. If David is willing to accept that he is trusting ignorance as it has been called to his attention by numerous contributors, I would take that.
As it stands now, I think he will eventually marginalize his position in the minds of others here.
It matters not . . . might as well pack up the discussion because it is game over. NASA has now determined that Aliens are getting ready to destroy the planet because we have been, bad, bad, badder and soiled our planetary diaper.
And that is why the NASA budget should be increased . . . because they are doing such stellar work for the good of humanity.
Childhood’s End.
===========
The NASA associated scientist that offered the concern regarding the Alien attack is reported to be employed at Penn State University. Is he also closely associated with M Mann? Someone should check the drinking water on campus!
“NASA has now determined that Aliens are getting ready to destroy the planet because”
Talk about misrepresenting the study.
So it’s a ‘study’ now, is it?
I see!
NASA talks about finding microbial life on meteorites, searching for organisms in Martian soil, and getting funding to land on the moon again someday, too.
Rocket jocks have a need to imagineer, and worse, many have little sense of when to stop geeking about it out loud.
Seems like harmless fantasy to me.
I mean, can’t you think of anyone you know connected to NASA who seems a little like that?
Why is it felt appropriate to calculate an average blackbody temp for a sphere by averaging the radiation when the formula used has a fourth power in it? (Stefan-Boltzmann)
First calculating the different temperatures and then averaging the TEMPERATURES makes much more sense to me.
Averaging temperatures can seriously mislead. Temperature says little about the actual quantity of heat. The end of the cigar and the ash that falls from it are close to the same temperature but only the cigar has the capacity to burn you.
Also, when calculating a temperature from average radiation from S-B the expression has a 1/4 power.
Don’t follow your explanation.
Daytime solarradiation can burn you seriously. Nighttime radiation not really afaik.
Still doesn’t make much sense to me to first spread incoming solar around the earth and expect the SB formula to give a sensible temp for that “average” radiation.
Solar radiation burns you because the UV photons are of a much higher energy, high enough to cause cellular damage. The IR photons emitted by the earth are of lower energy and cannot do that.
BenAW
I believe you’re right in your last line. Sort of.
If someone is doing exactly what you suggest, in the wrong way and for the wrong reasons, and then using their results wrongly, they ought stop.
However, the 1/4 power among other things means you have to have a very large change in radiant energy to get a very small change in temperature (and of course there are other complicating factors in the real world, such as that S-B is based on an imaginary ideal nonexistent color painted on surfaces).
It also means that for different levels of energy, the same relative change in energy (or temperature) means a different outcome on the other side of the equation, and even a small temperature level difference makes a huge energy difference.
Also, temperature density of different materials is very different. If you could transfer the heat in a swimming pool at room temperature into an iron nail, you’d liquify the metal, or some such. Specific heat capacity, maybe Google might have something on that search term.
Shorter answer, ‘sensible temperature’ is meaningful, but you either have to simplify your model of the world to limit all the complicating factors that lead to errors, or you have to do a huge amount of math and fill books with lists of all the factors and all the ways they interact, to get useful answers.
This it the nub of the problem so many people have with Claes’ methods.
Claes is an immensely bright theoretical mathematician. Far better at it than me, certainly. And that’s flattering me immensely.
Claes has a concept that has something to do with waves.
It’s not even an incorrect concept, at its heart. Likely.
It just requires far greater work than Claes appears to be willing to recognize is really needed to produce correct results.
And so Claes takes shortcuts, ignores parts of systems that turn out to be important later, makes up stuff as he needs it to gloss over the problems caused because there aren’t any brains in the world big enough or fast enough to turn his concept into a real way to describe what happens.
At least, that’s my take on it.
Hope it helps.
BenAW, if your reasoning about radiation and temperature were right, it would apply to power and voltage as well. In that case no one would use the concept of RMS voltage, they would use average voltage instead.
Have you ever wondered about the significance of RMS voltage? Happy to explain it if it’s not clear.
No worries, ‘safe & sound’…
http://www.guardian.co.uk/science/2011/aug/18/aliens-destroy-humanity-protect-civilisations
Based on what; exactly?
Well, here’s an interesting juxtaposition:
and
Smoke-em-if-you-gottem…
First Shirt
Judy, come on now and answer my question. You present a GHE based on radiation alone, and admit that climate is thermodynamics with radiation. Is your GHE about climate?
Professor Curry
In your equation 12.a it would appear that the calculation is based on the Earth radiating from the “solid Earth”.
Yet we know that most of the radiation to space occurs from the atmosphere at an average emitting height of 5km.
Although it makes little difference here, later on this becomes a major point of contention.
There also appears a typo for the surface of a sphere.
Yet we know that most of the radiation to space occurs from the atmosphere at an average emitting height of 5km.
Citation needed. (Please don’t cite the sentence “This is much colder than the conditions that actually exist at the Earth’s surface (the global mean surface temperature is about 14°C). Instead, the necessary –19°C is found at an altitude about 5 km above the surface.” This does not say what you said.)
Claes,
I agree. Judy like all GHE believers does not want to allow Postma or any other skeptic to factor into their discredited GHE anything as inconvenient as convection, conduction, adiabatic pressure and, heaven forbid, all that liquid water and the moderating effects of night and day.
As long as we let the religionists insist on restricting the discussion to radiative effects they can cling onto their discredited notions unincumbered by such inconvenient realities.
Judith Curry 8/18/11, 6:30 am Potential energy balance
Judith Curry can barely contain her revulsion at the position attributed to Skydragons, followers and authors presumably of the book Slaying the Sky Dragon by John O’Sullivan, Hans Schreuder, Claes Johnson, Alan Siddons, Martin Hertzberg, Joseph Olson, Charles Anderson, and Tim Ball. The book description and the reviews on Amazon say that the book debunks AGW and IPCC along with it, about which little doubt exists. But what Dr. Curry, posters on her blog, and reviewers on Amazon object to is the allegation that thee book denies, per Dr. Curry’s article, the existence of the greenhouse effect. The two positions are not comparable.
Joel Shore reviewed the book for Amazon, saying
One example of those who have unfortunately been duped is the reviewer here who states: “The global warming mechanism of carbon dioxide infrared radiation is impossible because heat can not flow from a cooler area (the atmosphere) to a warmer area (the earth surface). If this impossibility was the case it would violate the Clausius statement of the Second Law of Thermodynamics.” I teach thermodynamics and have published many papers in top physics journals in the field of statistical physics, which provides the underpinning of thermodynamics, and I can state categorically that this claim is utterly wrong. In all models of the greenhouse effect, be they toy models that one can work out on the back of an envelope or full-blown climate models that occupy the world’s fastest supercomputers, the flow of heat is from the earth’s (warmer) surface to the (colder) atmosphere as the 2nd Law requires. Bold added.
Dr. Shore is wrong, not in his physics, but in his reading. The passage does not describe the greenhouse effect. Rather it inarticulately describes the back radiation effect, alleged by AGW supporters here (and there) to have a warming effect, which violates the physics of thermodynamics. Back radiation is not heat (flow of heat is redundant, so let’s not repeat that mistake either). Vaughan Pratt’s block of ice thought experiment was great. Let’s extend it. You sit in an isolated, absorbing room with a huge block of dry ice and between you and the dry ice is an even larger block of water ice. The water ice has the same back radiation everywhere, but the water ice cools you and warms the dry ice. Knowledge of the back radiation alone is insufficient to proclaim warming. QED.
What might be inferred from Dr. Shore’s critique is that he couldn’t find a passage in Slaying the Sky Dragon that actually denied the existence of the greenhouse effect. I’ll check that myself when I get a free, searchable e-copy.
Dr. Curry goes too far when she says,
If you want to disprove the existence of the greenhouse effect, you need some sort of alternative explanation for a whole lot of fundamental physics that explains the infrared emission spectra as measured at the Earth’s surface and high above the emitting portion of the atmosphere (see Pierrehumbert).
Denying the existence of the greenhouse effect means invalidating the Beer-Lambert Law and the foundations of thermodynamics. If IPCC and the AGW model rely on either, it is not only implicit but well-hidden. Certain gasses in the atmosphere absorb radiant heat, acting in the most elementary model as a blanket, keeping Earth from cooling by radiation to deep space. That is sufficient as a statement of the greenhouse effect. We only need worry about the total absorption from the surface to TOA, and not lapse rates or layering.
The subject of the article is energy balance. The fact that Earth is always warming or cooling on climate scales is evidence that it is never actually in energy balance. As a hypothesis, nothing is wrong with the assumption. “If Earth were in energy balance, here is what one might expect: … .” Dr. Curry suggests as much when she writes,
The planetary energy balance equation has its greatest utility in the context of comparative planetology.
(This passage would be more suggestive of an assumption without the first The .) Still, Dr. Curry then goes through a model for the optical depth of the atmosphere. This model is weak and insufficient. Regardless that atmospheric temperature at the boundary is the parameter of interest in global warming, the atmosphere does not regulate its own temperature. It is but one fluid distributing thermal energy, the other being the ocean, and their relative importance is proportional to their relative heat capacity, estimated to be on the order of 1000 to 1 in favor of the ocean. Earth’s atmosphere is a byproduct of the ocean in relevant composition and temperature on global climate scales. A proper planetary comparison would be other planets with substantial surface water in the liquid phase. Perhaps that will be available in the next millennium.
The lead article gives the impression that Slaying the Sky Dragon, having denied the existence of the greenhouse effect (did it?), is wrong because AGW is substantially valid. That fits the fallacious model used by Askolnick and Dr. Shore on this blog, and by such sources as skepticalscience.org, that debunking erroneous anti-AGW claims tends to validate AGW. This fallacy gives great authority to the celebratory burning of straw men. This is the same illogic Askolnick and Dr. Shore applied to the politics of AGW: the existence of anti-AGW kooks and cranks on the political right validates AGW because it is a tenet of the left, notwithstanding the existence of kooks and cranks on the pro-AGW side. This weak justification for AGW is symptomatic of the model failing as a matter of science.
Trop sec, les M&Ms.
==========
The oceans will buffer the entire anthropogenic aliquot, biologically probably. Has the bottle been shaken first? I think not.
==============
Except for this bit of 19th century lore
“If a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to partially reverse the change.”
curtesy of Le Chatelier
… from my text Thermodynamics of Atmospheres and Oceans…
In the context of planets and climate the key word here is “Oceans”—i.e., they are why we are here and why everything is different here than anywhere else.
Don J. Easterbrook: “The Pacific Ocean has a warm temperature mode and a cool temperature mode, and in the past century, has switched back forth between these two modes every 25-30 years (known as the Pacific Decadal Oscillation or PDO). In 1977 the Pacific abruptly shifted from its cool mode (where it had been since about 1945) into its warm mode, and this initiated global warming from 1977 to 1998. The correlation between the PDO and global climate is well established. The announcement by NASA’s Jet Propulsion Laboratory that the Pacific Decadal Oscillation (PDO) had shifted to its cool phase is right on schedule as predicted by past climate and PDO changes (Easterbrook, 2001, 2006, 2007). The PDO typically lasts 25-30 years and assures North America of cool, wetter climates during its cool phases and warmer, drier climates during its warm phases. The establishment of the cool PDO, together with similar cooling of the North Atlantic Oscillation (NAO), virtually assures several decades of global cooling and the end of the past 30-year warm phase.”
If Easterbrook were 100% correct about this his conclusion about future cooling would be sound. If however he’s only 33% correct, which is more likely, then his conclusion goes out the window.
It is a little bit wrong – the effect is Pacific wide rahter than limitied to the north east Pacific.
Verdon and Franks (2006) used ‘proxy climate records derived from paleoclimate data to investigate the long-term behaviour of the PDO and ENSO. During the past 400 years, climate shifts associated with changes in the PDO are shown to have occurred with a similar frequency to those documented in the 20th Century. Importantly, phase changes in the PDO have a propensity to coincide with changes in the relative frequency of ENSO events, where the positive phase of the PDO is associated with an enhanced frequency of El Niño events, while the negative phase is shown to be more favourable for the development of La Niña events.’
The cool PDO and intense La Nina – lead to intensified drought in North and South America – but enhanced rainfalls elsewhere. Floods in Austraia – greening of the Sahel – enhanced ndian monsoon – etc.
The NAO seems to be solar driven – e.g. http://iopscience.iop.org/1748-9326/5/2/024001
There is a similar southern influence – which is linked to the Pacific Ocean states.
The planet is cooling and for how long even Kim don’t know.
The planet is cooling and for how long even Kim don’t know.
Right. On a geological time scale, Earth will exhaust its carbon based fuels in the blink of an eye and can then get back to the business of varying its temperature the same seemingly capricious way it’s been doing for hundreds of millions of years. I imagine CO2 will be back to 250 ppmv or so by 2150 at the very latest. That’s a hundred times closer even than the Younger Dryas. I’m confident our descendants will find some way to avoid getting that cold, if only by emitting a little methane (less hazardous to the ocean than CO2 perhaps), assuming some of them are still around.
By way of even more random projections, in the meantime CO2 will continue to drive up the temperature, with the downswing of the PDO and AMO (Atlantic Multidecadal Oscillation) no longer able to offset it as effectively as during 1940-1960. Those two oscillations were interfering constructively in 1925, but by 2035 they will be interfering destructively and anthropogenic influences will no longer be the main factor in climate change, they will become the only factor. El Nino events and solar cycles will still come and go, but they’re too short-lived to be relevant to secular climate.
Oh, and there’ll be thunderstorms all this week on the US southeastern seaboard. (Have to do something to maintain my forecasting credibility in the short term. ;) )
Show me a description that talks about energy, mass, specific heat and conduction, convection and radiation in relative portions and I will start to believe.
To me, G&T, Postma, Johnson, and Nordell make much more sense. Maybe they’re not perfect, but they make sense.
As far as I can figure, the presence of an atmosphere on any planet has more to do with gravity and density that IR absorption/emission. I dare anyone to propose and conduct an experiment to solve this problem.
What problem? IR absorption doesn’t keep the atmosphere on the planet, it is a feature of the existing atmosphere.
Oh, you want a textbook. I suggest Judy’s.
Facts are facts and everything else is dogma. “Alternating climatic warming and cooling has occurred about every 27 years since about 1470 AD… In 2008, NASA satellite imagery confirmed that the Pacific Ocean had switched from the warm mode it had been in since 1977 to its cool mode, similar to that of the 1945-1977 global cooling period. The shift strongly suggests that the next several decades will be cooler, not warmer as predicted by the IPCC.” (Easterbrook)
you realize that the satellite imagery is CREATED by applying the physics of RTE. That is, to sense the SST ( the temperature at the surface), the radiance at the sensor has to be ADJUSTED to account for the transmission of IR through the atmosphere. Simply, the sensor data is run through a physics model. That physics model take in the radiance at the sensor and CALCULATES the temperature at the surface. That calculation contains physics that the Slayers deny. So If you believe in that satellite data you have tacitly accepted the VALIDITY of the physics used to calculate it.
Do you believe in satillite imagery? then the Slayers are wrong. It’s brutally simple. No point in talking past this one.
+1 for Mr. Mosher. Willis and Science of Doom were my first two accessible sources for understanding these basic issues. It’s only a little bit tricky, really–you have to get the system boundaries clear but then everything kind of falls out.
you will find that they usually leave after I point this out to them
So If you believe in that satellite data you have tacitly accepted the VALIDITY of the physics used to calculate it.
So Steven, what are you advocating here? That we reject the validity of physics? All of it? Or just those parts that don’t fit in with your personal world view?
Vaughan,
My reading of Steven is the opposite. He’s pointing out that many skeptics are illogical, when they accept and use results calculated based on known physics to attack the same physics.
Random firing killed allies.
Guilty as charged (blush). :(
I am not your allied though, hahaha.
yes. They are illogical. I have no issue with a skeptic who claims no knowledge. But one they use data ( like satillite data) they are bound by the force of logic to accpt the physics that created that data product.
This is an unrecognized point in these debates.
I’m claiming this. Everytime a skeptic cites a piece of ‘evidence’ or data, they are logically bound to accept the physics that produced that data. Simply, if you cite cloud data from a sensor platform in space, you tacitly accept the radiative physics code that is run on the raw sensor output to create the final data product. In short, you accept RTE every time you quote or cite satillite data products
Now I know why I have so much trouble beleiving the Satellite data, it so often conflicts with the observable world. Like last month the SH was supposed to be hotter than average. That is not what the southern hemisphere reported.
Do you believe a weather radar when it tells you how far away a storm is?
Do you belive the physics that allow us to shoot down a missile?
did we land on the moon
Do you use a GPS?
steven,
That is understood.
But what does this have to do with climate doom?
Judy, you state:
“If radiative transfer is the only process occurring in a planetary atmosphere, the surface temperatures of the planets would be determined solely by the net radiation at the top of the atmosphere. Thus, the equatorial regions would be warmest and the poles would be extremely cold. .. There are two fundamental time scales that determine how a planetary atmosphere transfers heat. The radiative timescale, trad, is the time it would take for an atmosphere above some pressure level p0 to reduce its temperature by 1/e of its initial value via radiative cooling if solar radiation were turned off. The dynamic timescale, tdyn, is the time required to move a parcel over a characteristic distance in the atmosphere and, in so doing, transport heat from one location to another.”
I don’t think anyone could quarrel with this in general, but as a small point, I would add that horizontal gradients at the surface are also determined by convective adjustments to radiative transfer that in most regions operate to mitigate some of the surface temperature rise that would be dictated by radiative transfer alone. It would then be the radiative/convective imbalances between regions that determine the rate of heat transfer. The convective adjustments themselves operate over relatively short timescales (days to weeks). This is much slower than the radiative timescales for an atmosphere considered only in isolation from the surface, and which lead to atmospheric adjustments that are almost immediate. However, further atmospheric changes result from the warming of the surface due to back radiation from the atmosphere (“downwelling longwave radiation” in the more formal lexicon). Feedbacks add a further element of complexity.
Convection, a vertical phenomenon, is of course also part of the horizontal air mass transport via its role in the creation of pressure gradients and wind.
Where would a person learn the answers to:
* How much energy is absorbed by the atmosphere directly from incoming solar radiance, and at what frequencies does this occur?
* What frequencies are absorbed by GHG from outgoing radiation from the earth’s surface, and what percentage of total outgoing radiated energy does this represent?
* What frequencies are re-radiated by the GHG molecules that have been excited by outgoing radiation?
* What is the duration of excitement in an excited GHG molecule, and what determines this duration? How many levels of excitement can a GHG molecule maintain, and is the radiated frequency for each level of excitement the same as for all levels of excitement? Simply put, does it change color as it gains/loses energy? Limit responses to atmospheric energy levels, not what is possible in the presence of nuclear fusion.
* What is the opacity of the earth’s atmosphere at the frequencies being absorbed?
* What is the effective impedance of the atmosphere to those outgoing frequencies whose transmission the atmosphere is impeding?
* A number of ways have been offered to describe the back radiation of energy by excited GHG molecules. In a simple form this works like a spherical mirror. Perhaps those familiar with radar cross section analysis recognize the pattern. Anyway – is there anything about a GHG molecule that would generate a non-spherical pattern of radiation and if so is there anything about a GHG molecule that would cause a non-random alignment of non-spherical radiation patterns?
* A certain amount of energy is radiated back into space from the surface and this happens at the speed of light. Of all the energy that reaches the earth’s atmosphere or surface, how much is immediately reflected unimpeded back to space and lost forever?
Several of these obviously are exploring the opacity of the atmosphere and the critical frequencies that are most affected by that opacity, and the percentage of total outgoing energy that are contained in these critical frequencies.
Many of your questions about the energy budget can be found here. See figure 1 (on the last page) for a quick overview.
Or in simpler terms try http://www.nasa.gov/pdf/62319main_ICS_Energy.pdf for percentages.
You have a couple of interesting questions. “Anyway – is there anything about a GHG molecule that would generate a non-spherical pattern of radiation and if so is there anything about a GHG molecule that would cause a non-random alignment of non-spherical radiation patterns?” The short answer is no, but longer is yes because the GHG molecule is effected by its environment. At the surface collision dominates energy transfer and high in the atmosphere nearly pure radiative energy transfer dominates. So propagation of the infrared is easier out than in. Water vapor decreases dramatically with altitude. Since water vapor and carbon dioxide have overlapping portions of their emission/absorption spectrum a relatively small portion of the CO2 spectrum centered around 15 microns produces most of the down welling radiation which has a more opaque window down that up due to the wings of the water vapor spectrum around 15 microns. So while CO2 radiation is isotropic, its impact is not predominately isotropic below the tropopause due to interactions.
That’s my story and I’m sticking to it.
dp
see also Miskolczi’s graphs of quantitative radiation heat transfer.
Judy’s text looks really good from the Look inside feature at Amazon. From the look inside I already realized one of my mistakes that GHE has 2 acronyms – Global Heat Engine and Green House Effect doh!
At over $100 it’s a bit pricey, maybe it will be put on creative commons someday(hint hint).
It’s over already. And, so is global warming. Look at the phenomena of global warming as it relates to the future of humanity on the planet. You will see that the only human-related factor of any consequence to the survival of Western society is the growing culture of self-defeating nihilism.
“The ramifications of the global cooling cycle for the next 30 years are far reaching―e.g., failure of crops in critical agricultural areas (it’s already happening this year), increasing energy demands, transportation difficulties, and habitat change. All this during which global population will increase from six billion to about nine billion. The real danger in spending trillions of dollars trying to reduce atmospheric CO2 is that little will be left to deal with the very real problems engendered by global cooling.” (Easterbrook)
Judith,
I’m not saying I believe this, but just to play devil’s advocate, there is an alternative explanation that I don’t believe your textbook addresses.
If we model the atmostspere as an ideal gas, i.e. PV = nRT, the the force of gravity imposses a pressure equal to G= g x Ma x Me/Re^2 where G is the force of gravity, g is the gravitational constant, Ma is the mas of the atmosphere above the point we are interested in, Me is the mass of the earth, and Re is the radius of the earth.
Playing with the numbers gives us the adiabatic lapse rate: -alpha =dT/dz, which tells us the temperature of the atmosphere decreases with height, being coulder at elevation and warmer at the surface. Of course we know this is true of the troposhere. Hence the difference between the blackbody temperature (Te) and the actual temperature at the surface (To) could possibly be explained simply by the fact that most of the outgoing radiation is actually occuring at an elevation of about 5km if I’m not mistaken.
Is there anything I’m missing?
John,
Gravity determines the density profile of the atmosphere, when the effect of varying temperature is also taken into account. It doesn’t determine by itself the temperature profile. If it did, the stratosphere could not have a totally different temperature profile. The temperature profile is a combined effect of the gravity, heating of the surface by radiation, including the effect of greenhouse gases, and emission of energy from the top of troposphere. The effect of all these factors on the temperature profile is controlled by the convection and the cooling of air, when it rises in many areas, and warming of air in other areas, when it descends.
Very small part of radiation is leaving Earth from an altitude close to 5 km. Almost all is leaving either from significantly higher (close to 10 km) or lower including the surface. 5 km is only some kind of effective average.
Pekka
I didn’t say gravity accounts for everything. But if you compress a column of gas it does heat up. As for the stratospere, there obvioulsy is an elevation where other factors exceed the effect of gravity due to the inverse square nature.
Since temperature itself is not an actual physical quality, merely an average, I don’t think that disturbs the concept of an “effective height” being merely an average. For that matter the blackbody temp is merely an average.
BTW: nothing in my alternative would neccesarily upset the concept of global warming warming becasue it still doesn’t address the cause of the effective radiation point being at a height of 5km or what might change that.
At least I don’t think so without further analysis.
John,
You are perfectly right, when you refer to heating of gas, when it’s compressed. That’s exactly the mechanism that determines the adiabatic lapse rate as soon as we have a driving power that keeps convection alive. That driving power is formed by the flow of heat through the troposphere, when the surface is heated by radiation and the top cooled by emission of radiation to space.
I think this question gets to the heart of a lot of confusion in these recent threads. That is, would an atmosphere like the Earth’s with no IR-absorbing (i.e., ‘greenhouse’) gases be isothermal or does a temperature stratification arise solely from gravity, the laws of thermodynamics and the ideal gas law?
My own intuition on this was cloudy (no pun intended) and I asked the question in one of the earlier threads. The consensus (pun intended this time) of the experts seemed to be that such an atmosphere would, in fact, be isothermal or very nearly so. The lapse rate tells us about the convective stability criterion in an atmosphere but it’s all predicated on that atmosphere having energy pumped into it from the bottom. My understanding is that the conduction at the surface layer isn’t efficient enough to do very much and so most of the energy absorbed at the surface would be radiated directly to space through the optically thin atmosphere and would be pretty close to a 255K blackbody. Leaving us pretty darn cold. Another way of looking at this is that the tropopause moves down to the ground and the entire atmosphere would be one big stratosphere.
Judith, et al., have I got this pretty much right?
FiveString,
You got it right at least, if you ask me.
FiveString,
My understanding of it is that an atmosphere with no LW-absorbing gasses would not be iso-thermic. Gravity would still impose an adiabatic lapse rate. However, without LW-absorbing gases the earth would be radiating at the surface instead of some other effective height.
But we must remember that water vapor is the dominant LW-absorbing gas in the atmospshere. So any planet with abundant H2O will have significant LW-absorbing gases in its atmospshere.
Gravity leads to the barymetric formula for the density profile (i.e. approximately exponential decrease with altitude). It doesn’t lead to adiabatic lapse rate in absence of convection and convection needs a continuous driving energy flux.
(I know this is an issue that some people contest including some, who agree with me on most other points.)
I’m not sure I agree with you on this point. The lapse rate is a requirement of conservation of energy. The potential energy of molecules at higher elevations is converted to kinetic energy (temperature) at lower elevations. That is the driver of convection, not the other way around.
Nonetheless, the two phenomena must coexist regarless of which is cause and which is effect. I think we both can agree on that.
John,
You are not alone in making that error in thinking, but it is an error. The way to figure out, what really happens is to do quantitative calculations based on the well known equations of thermodynamics. That proofs directly that your explanation fails. It cannot satisfy the first and second law of thermodynamics and other very fundamental laws of physics.
You can find the correct calculations on any text book that includes atmospheric physics. The textbooks don’t usually waste space in explaining, why erroneous ideas are wrong. Therefore it may be difficult to find that in print, but it should suffice that the correct answer is easy to find.
Pekka,
You and I are speaking at cross purposes. I am confining myself to the adiabatic (no energy added or subtracted) processes driven by gravity. You are dicussing non-adiabatic process. Those are certainly an important element of atmosperic physics, but not for the point I am making.
My point was to show that we get the same result (a warming of the planet due to absobtion of LWR) without having to invoke back-radiation or some of the other elements of RHT that seem to be so diffcult for some to grasp.
I think the term “greenhouse effect” is a horrible misnomer, but I have no dispute with the physics.
John,
Such processes do not exist. The word “adiabatic” refers to, what happens to the air parcel (i.e. it’s assumed that no energy flows across it’s boundaries to neighboring air), while it’s rising, but it doesn’t mean that no energy would be needed to drive the convection. That’s needed continuously at the bottom, and energy must be taken off at the top.
The atmosphere is not in a thermodynamic equilibrium, it’s in a stationary state, where flows continue driven by the radiative processes at the bottom and at the top.
(Just found this part of the discussion now, very sorry I missed it earlier.)
John, Pekka is quite right about the isothermal solution in the simple situation it assumes, with no convection. However it is possible to arrive at this solution without any equations.
If you model the atmosphere as a single molecule at the altitude of the real atmosphere’s tropopause, about 13 km, it will drop with acceleration g until it hits the ground at sqrt(2*9.8*13000) ~ 500 m/s. This is the process of converting potential energy to kinetic energy.
The main reason this doesn’t happen with our atmosphere’s 5140 teratonnes of air molecules is that it is so hot that the molecules are in a permanent state of dashing around at the same 500 m/s calculated above and colliding with each other every 140 picoseconds. This creates a pressure that expands the atmosphere and raises the tropopause to its 13 km average altitude.
Nevertheless the same principle as for the one-molecule case is still in effect, but now masked by the statistics of colliding molecules. Every molecule wants to fall to the ground eventually, but it is competing with all the others wanting to do the same thing.
A requirement for equilibrium in this scenario is that all molecules have the same RMS velocity, equivalently the same average energy. Imagine to the contrary that the population is divided into hot and cold molecules, a binary division rather than the gradient associated with nonzero lapse rate. This violates adiabaticity, and the cold molecules will then preferentially fall downwards, displacing the hot molecules but gaining kinetic energy in the process until they themselves become hot molecules.
As the easy calculation above showed, the kinetic energy gained by a molecule starting at rest, i.e. close to absolute zero temperature, and falling from the tropopause to the ground equals that of the molecules at sea level in our normal atmosphere.
The tropopause is the natural height to which molecules at STP at the surface are flung when traveling vertically and miraculously avoid all collision.
The stratosphere exists because the Maxwell-Boltzmann distribution includes more energetic high fliers that are naturally carried above the tropopause. The stratosphere’s inverted temperature profile results from anti-greenhouse gases, in particular ozone.
Much higher still, the solar wind heats the thermosphere to 2300 K or more in the day, cooling to 800 K or so at night.
If you model the atmosphere as a single molecule at the altitude of the real atmosphere’s tropopause, about 13 km, it will drop with acceleration g until it hits the ground at sqrt(2*9.8*13000) ~ 500 m/s. This is the process of converting potential energy to kinetic energy.
I have three reasons for retracting this claimed connection with the tropopause: (i) Arthur Smith thought it was just a coincidence; (ii) I estimate the corresponding altitude on Venus at 23.5 km which is nowhere near the tropopause of Venus; (iii) real tropopauses needn’t have much to do with this idealized situation of a column with no energy flux in or out.
I think except for this coincidental connection with Earth’s tropopause, the rest of what I wrote should be ok. Just replace every occurrence of “tropopause” with “at altitude 13 km,” and remove any tautologies that result like “13 km is at 13 km.”
I promise to keep saying something nutty from time to time, though I can’t predict how frequently.
John,
The lapse rate is a dynamic phenomenon, it is driven. One might argue the the convection does not supply significant sensible heat, although it does, but the existence of rain tells us the latent flux from the surface into the atmosphere is significant.
Because of the tropopause, energy cannot be escaping the atmosphere by either conduction or convection. It escapes by radiation.
The driver is the net radiative flux out of the atmosphere, without it the lapse rate would diminish and the atmosphere would tend to stratify and the convection would tend to decrease progressively.
The radiative flux is determined by the temperature and the GHGs present, it is not caused by the convection. The convection is a response to the radiative energy deficit.
Alex
Would the atmosphere be isothermal if there were no greenhouse gases.?
Lets look at the planet if this came to pass namely that gaseous H2O and CO2 did not radiate in the IR.
All other things being left the same.
Postma has calculated that on the Sun facing side of Earth there will be temperatures around 60C at the equator and overall average of 30C.
There are underwater volcanoes.
So it appears that we will have clouds.
Clouds composed of condensing water are in fact BETTER radiators than the greenhouse gases.
Radiation from the Earth surface between the clouds will also be possible.
So the adiabatic lapse rate conditions will be unaltered.
Therefor there is little reason to think that the climate would be isothermal.
Perhaps even it might be not all that different from the present.
“That is, would an atmosphere like the Earth’s with no IR-absorbing (i.e., ‘greenhouse’) gases be isothermal or does a temperature stratification arise solely from gravity, the laws of thermodynamics and the ideal gas law?”
In the absence of convection, the atmosphere would be isothermal. Adiabatic lapse rate stratification cannot arise purely from gravity – work must be done by the external environment to maintain it. If air is moved upwards it will expand and cool, and if it is moved downwards it will be compressed and will warm up, but it requires another force to move it – it won’t move on its own. And if nothing moves it around, then conduction will eventually equalise temperatures.
Think of it as like a refrigerator. Pumping a fluid round a circuit of compression and expansion will maintain a temperature difference, but you need an external power supply for the pump. In the atmosphere, this comes from insolation being uneven, and the resulting temperature differences provide the entropy to drive the combined heat engine/heat pump. Turn the external power to the pump off, and the refrigerator stops.
“The lapse rate tells us about the convective stability criterion in an atmosphere but it’s all predicated on that atmosphere having energy pumped into it from the bottom.”
Convection can also occur because of the equator to pole differential, and the day to night side differential. Heat supplied at the equator causes air to rise, circulate, and settle near the poles where it transfers to the surface and radiates to space. (Hadley cells.) Similarly, heat supplied at the equator causes ocean water to rise, spread out towards the poles, where it cools and sinks, returning at depth to the equator. The driving force behind deep ocean currents is also convective, although no energy is being pumped in at the bottom. The claim that convection requires energy to be pumped in at the bottom and radiated from the top before it will occur is false.
In the absence of convection, the atmosphere would be isothermal.
Convection can help to maintain an adiabat, but the temperature profile of an atmosphere without convection would be determined by a multiplicity of factors and can’t be described without knowing what else is going on. As an example, In the stratosphere, convection is inhibited, and the result is a temperature inversion.
The stratosphere has a temperature inversion because it contains a greenhouse gas – ozone.
Mostly because ozone absorbs short wavelength energy. You also need to have the right vertical structure of the solar absorber.
But your counterexamples all begin with a heated atmosphere – in the absence of any radiative opacity in the atmosphere the only heat transfer mechanism is conduction at the ground itself. My understanding (perhaps wrong) is that conduction is so inefficient compared to the radiation straight to space that there will be very little heat to transfer via convection.
I found the Lacis et al. (2010) paper interesting in this regard, although they only model the removal of the noncondensing GHGs and aerosols, which leaves lots of H20-based opacity. Even so, it got pretty cold pretty fast.
Insolation approximately balances radiation at about 255 K, so the surface will contain plenty of heat to be conducted to the air. Without convection, the air would slowly heat until it was the same temperature as the surface it is in contact with. No matter how slow the transfer, such an equalisation is inevitable. But having air at different temperatures at the same altitude in different parts of the world is mechanically unstable. The differing densities lead to pressure differences which drive air flow. Convection results.
It might take a larger equator-pole temperature differential to drive a given amount of circulation, but the atmosphere couldn’t be static.
While air isn’t very conductive, it’s conductive enough that they use a vaccuum in thermos flasks rather than air – despite the expense and the risk of breakage.
Point taken. I’m enjoying these thought experiments – thanks for the thoughtful responses.
You are very welcome. I enjoy it too – the process of trying to explain these points clarifies my own thoughts as well.
It was a good question.
Adiabatic lapse rate stratification cannot arise purely from gravity – work must be done by the external environment to maintain it.
No I don’t think this is right. It can. Molecules at the bottom of the atmosphere have the same energy as at the top of it. Except that at the bottom it’s kinetic energy, which means a higher temperature, and at the top its lower kinetic energy and higher potential energy.
It’s all caused by gravity.
Tempterrain,
You have mistaken. This has been discussed in so many messages during the last couple of days (and before) that I leave to you to find the sources. Naturally you can use also any textbook or other main stream source to find the arguments.
Well if I’m mistaken then Wikipedia have it wrong too. They say ” While most often applied to Earth’s atmosphere the concept can be extended to any gravitationally supported ball of gas.”
I’d agree with that. Certainly convection and moisture content does complicate the picture in the Earth’s atmosphere leading to the possibility of temperature inversions etc; but, this doesn’t change the basic principle that any column on gas subject to a garvitational field will have a adiabatic temperature gradient.
And the Uni of San Diego Have it wrong too!
http://earthguide.ucsd.edu/virtualmuseum/climatechange1/02_1.shtml
http://earthguide.ucsd.edu/virtualmuseum/images/GreenhouseGasesRegulatingTemp.html
Tempterrain,
Your quote from Wikipedia doesn’t say anything on the mechanism that produces the lapse rate, your links tell only that there is a lapse rate.
The San Diego presentation is actually terrible. Indicating that there would be some radiative surface at 5000 m is so misleading that it’s not surprising that skeptics continue by creating their own non-physical theories. The text tells that it’s an apparent temperature “surface”, but this reservation doesn’t remove the fact that both the picture and the main text are grossly misleading. The other picture shows more correctly that the surface is one important source of radiation, but as a whole that text is simplified in a way that I find unacceptable.
The Earth doesn’t radiate like a blackbody of 0F. It radiates about that much in total, but with a different spectrum and from all altitudes from surface to top of atmosphere. Simplifying that as the UCSD link does is counterproductive in my view.
Why do you suppose molecules at the bottom have to have the same energy as those at the top? Why could you not have molecules with more energy piled on top of those with less?
The mechanism is that the distribution mixes to maximize entropy. The specific decrease in atmospheric pressure with altitude can be demonstrated by applying the maximum entropy principle. The basic constraints on the system are an average energy on the system as a whole. The essential derivation is very simple, but a more detailed explanation is given in the paper “On Maximum Entropy Profiles”, W.T.M. VERKLEY and T. GERKEMA.
What I find interesting in all this discussion is that the Stefan-Boltzmann law comes directly out of statistical mechanics, which essentially defines the amount of disorder in a black-body system. Yet the skeptics somehow conflate what this is all about when they claim that the S-B energy balance does not work out and the numbers come out too low. But the capture of various radiation wavelengths by gases will surely effect the statistical mechanics of this distribution with altitude. The system will maximize entropy and if this requires a smearing of temperature in stratified layers, nature will surely accommodate this effect.
I just don’t get it. The skeptics assume disorder exists, otherwise the S-B law is wrong, but then claim that constraints on the system, ala Maximum Entropy constraints, can not have any effect. I use entropy arguments all the time on various physical phenomena and don’t see why someone could not come out with some simple MaxEnt explanations to explain the energy balance more elegantly.
The maximum entropy solution for an atmosphere in thermal equlibrium (as contrasted with a stationary atmosphere with a continuous upwards energy flux through it) is isothermal with a exponentially decreasing density.
The adiabatic lapse rate is a property of the stationary state, when convection maintains a steady upwards energy flux.
That is the basic solution, agreed.
The next step is to apply another layer of disorder to the system, or maximum entropy on another parameter to derive what is happening. For example, the upwards energy flux could be MaxEnt variable as well. This approach is also referred to as the technique of superstatistics, which is just catching on in the last few years. I am fishing a little bit here because I am still getting up to speed on the dynamics.
Part 2:
The Verkley and Gerkema paper I mentioned does include convection. The general idea is that they use MaxEnt subject to the mass and energy constraints (getting the conventional isothermal result) and then extend it with the constraints of a constant integrated potential temperature. This accounts for a steady-state convection.
You have to really look at the V&G article and the excellent agreement they get with the data for the standard atmosphere to get an appreciation for this work.
The only caveat is that they say about the additional constraint
One of the peculiar aspects of maximum entropy is that it ends up working well in spite of people having a hard time explaining why.
Gian-Carlo Rota a few years ago said this:
I could have mentioned in my earlier answer that I know the paper of Verkley and Gerkema and I have referred to it in my earlier discussions on the temperature profiles of gas columns. That discussion started on this site, but continued on my own site, when it started to be too much out of topic.
I stated in some earlier comment here that statistics should be basis of any extension of the maximum entropy principle to non-equilibrium systems based on the same basic argument that leads to the equilibrium results. I.e., one must start by determining the proper phase space density, and then analyze the macroscopic physics through the calculation of the most likely set of macroscopic variables. That set of macroscopic variables has the property that the volume of the microscopic phase space that corresponds to it must be large, but also such that they are not excessively unlike. Deriving the equilibrium thermodynamics in that way is surprisingly easy, but the task is much more complicated for non-equilibrium systems.
Quantum mechanics might actually make the approach easier, because the phase space density is simpler to understand in quantum mechanics. The entropy is also very easy to introduce in the quantum mechanical derivation. (I have used that approach in a course of thermodynamics that I lectured years ago for students, who had had a course of QM.)
What I also find interesting about the Verkley and Gerkema paper is in how recent it is, dated 2004. It really demonstrates that one can always find some new simplifying views based on combining different physical principles. Their approach generates a surface temperature of 287, an equivalent isothermal temperature of 261, and excellent agreement to the edge of the troposphere.
Isn’t this everything you need to understand a steady-state lapse rate?
What I also find interesting about the Verkley and Gerkema paper is in how recent it is, dated 2004. It really demonstrates that one can always find some new simplifying views based on combining different physical principles. Their approach generates a surface temperature of 287, an equivalent isothermal temperature of 261, and excellent agreement to the edge of the troposphere.
Isn’t this everything you need to understand a steady-state lapse rate?
The role of the lapse rate and it’s value has been known for much longer. As far as I know the Manabe – Wethrerald paper of 1967 is given most credit on this point. They considered in their paper also the moist atmosphere making it more realistic. Manabe had an earlier paper, where the moisture was not taken into account with Strickler in 1964, but I haven’t looked at that.
Thus I don’t think that there’s anything new in the quantitative results of the Verkley – Gerkema paper. It’s content is more in the way the derivations have been done and the theory discussed. I cannot say, how much really new the the paper has even from that point of view. I haven’t seen exactly the same content elsewhere, and the paper was accepted for publication, but I’m not a research level specialist on these issues, and wouldn’t know even, if everything could be found in earlier papers, and possibly in papers published long time earlier.
My comment was a bit beside the point concerning the fit with the U.S. Standard Atmosphere with the intermediary constraints, but I would expect the standard atmosphere be affected by moisture. My impression is that the paper doesn’t include moisture, making the value of the fit be of little significance, more a coincidence that anything else.
WHT,
Regarding the dating: I am aware that these approaches are still active.
I have glanced at the paper, Abstract and Conculsions, trusting them to get the calculations right.
These results are tantalising, that strikes me as common with MEP approaches.
They recognise that the choice of constraints is not clear from physical principles:
“The question then arises what these constraints should be. Here, we have taken, following Ball (1956) and Bohren and Albrecht (1998), constancy of the integrated potential temperature as a single additional constraint 3, but this choice is of course open for debate. In our view, this particular constraint still lacks a solid physical basis; yet, the above results give reason to expect that the construction of such a basis may be possible because the three constraints 1, 29, and 3 together lead to a temperature profile that corresponds remarkably well to the tropospheric part of the Standard Atmosphere.”
but are hopeful of a fruitful conclusion.
I hope I am being fair.
Plausible constraints lead to credible results, this is trying to tell us something but it is not clear as to what that is.
It is my impression that MEP gets rapidly to intersting and potentially insightful results but then further progress becomes much more difficult.
I wish them well, it is a minority persuit but these issues are important and the more the merry in my book.
Alex
They are applying equilibrium type methods to non-equilibrium thermodynamics. It’s not surprising that the approach is not well defined.
That is true insofar as doing the variational approach with more constraints, the complexity quickly increases.
One of the most interesting domains recently has been in quantifying ecological biodiversity. It works so well that some researchers have suggested giving up detailed modeling of individual species (the explanatory) and simply use the statistical which doesn’t purport to explain succession or niches.This is a state space approach and the species fill up the state space consistent with maximizing entropy.
WHT – For the record, I should state that the conclusion that an isothermal profile is the maximum entropy state for a radiatively inert atmosphere is not “agreed”, although Pekka has made a strong argument for this conclusion, with references, which I’ve read. I don’t say this with a wish to repeat the arguments here, but simply to point out that when an atmosphere is coupled to a planetary surface, considerations may apply that don’t apply to an atmosphere in isolation. Pekka may be right, but I remain agnostic on this issue.
I would be happy to discuss this further somewhere, perhaps even by email, but probably not in this blog, because it doesn’t apply to our atmosphere and climate.
Fred,
The extended maximum entropy approach variationally includes both isentropic (adiabatic) and isothermal profiles. That’s the way that nature works in filling up the state space.
Use of the variational principle tells a good reason for the fact that the extended maximum entropy method works in appropriate situations. Based on the method, it’s also possible to rationalize, when it’s likely to work and when not. It’s, however, not based on a well understood theoretical understanding in the same way as thermodynamics can be deduced from statistical mechanics.
When the overall dynamics is considered rather than details within a system, whose overall dynamics is postulated (which can be based on empirical evidence), the lack of a solid theoretical basis means that specifying the right constraints may remain ambiguous. As long as the constraints are ambiguous, the result that relate to the overall behavior cannot be deduced from the principle. That seems to be the problem in the Verkley – Gerkema paper.
As I said when I quoted Rota, MaxEnt is still not well understood but it can be amazingly useful. Somebody may yet figure it out one of these days.
MaxEnt is still not well understood but it can be amazingly useful.
Right, it’s hard to see why entropy should increase with time. It seems to me the converse is more understandable: time increases with entropy.
Picture the universe as a transition system organized as a metric space whose points are states and whose metric d(x,y) = 1/p(x,y) where p(x,y) is the probability of a transition from x to y, with p(x,y) = p(y,x). Suppose further that most states are high entropy, just as most strings of 10 letters are random words. Random motion will then tend to increase entropy simply because there are more high entropy states than low. (If this seems contrary to p(x,y) = p(y,x), bear in mind that these probabilities are really tiny, and only amount to something when you consider the probability of a transition to one of a quadrillion of nearby states, most of which are high entropy.)
Time is merely an illusion created by this random motion. The past is absence of change, by which we are able to remember things, and we say that what we remember is that which is in the past. The future is change, and the most likely transitions are those most likely to increase entropy, making the future somewhat of a mystery.
But not a total mystery, because some things can be seen to be changing more slowly than others, and it is therefore reasonable to expect to find the slowly changing things still in our future. Planetary orbits change very slowly, making them predictable much further into the future than the trajectories of air molecules, which at sea level change every 150 picoseconds or so (do the math: air molecules move at 500 m/s and enjoy a mean free path of 70 nm).
Just another of my crackpot theories to spice up Judy’s blog. ;) Probably not even mine either, nothing new under the Sun and all that. Back to more serious stuff.
Vaughan…emergent spacetime. Have you seen Erik Verlinde’s paper?
http://arxiv.org/abs/1001.0785
My simple theory of why many fat-tail probability events occur has to do with many observables being reciprocals of the measures that show either exponential or normal distributions. It has nothing to do with critical phenomena, but just that you get fat-tails mathematical when you take the reciprocal of a PDF.
Oh, and Verlinde’s paper is the one where he claims gravity is entropy, right?
David N, thanks very much for the pointer to Verlinde’s paper. His account goes far further than my “short story,” addressing space, mass, and energy whereas I only considered time. It is also much more quantitatively detailed, reflecting his much stronger physics background.
It should be obvious I’m very sympatico with this statistics-based “emergent” point of view. I’m therefore looking forward to absorbing Verlinde’s ideas and reconciling them with some of my own state-and-duality-based ideas (under the rubric of Chu spaces) about the statistical origin of Planck’s constant as a quantity whose reciprocal can be taken as an indication of the size of the universe. For Verlinde h is just a convenient but arbitrary quantity, whereas in my account it is not at all arbitrary.
My tastes run to the least sophisticated mechanisms that do the job, and I’m hoping for statistical accounts of these sorts of phenomena that approach the elegance of the (nonstatistical) derivation of special relativity. Not on the top of my stack right now, but hopefully it will bubble up in due course.
John – You addressed your question to Judith, but if she is busy elsewhere, I’ll respond in the meantime. The lapse rate is not an “alternative” to the greenhouse effect (GHE), but is an essential ingredient of the effect. Without the lapse rate, the GHE could not exist. Te is determined by the need of the climate system to emit energy at the same rate it is absorbed. Without the GHE, that would occur at the surface. However, the IR opacity of the atmosphere requires the atmosphere to emit that energy at a higher altitude, where greenhouse gases are sparse enough to permit the energy to escape. Because that altitude is colder than the surface (via the gas laws and gravity), the lapse rate requires the surface to warm up above Te.
Fred,
That was my inuitive sense of it. What I like, at this point, is that the adiabatic lapse rate explanation does not seem to require the “backradiation” argument that seems to be such a sticking point.
As I understand the debate, “backradiation” has become a straw man argument.
The argument against back radiation has become a strawman argument, or at least a totally false argument.
7/10ths of the surface is ocean. This is heated by Solar shortwave radiation only.Back radiation welling downwards from the atmosphere has only a negligible effect on the energy contained in the ocean, and the rate of it’s loss to space. This is because the net flow of longwave radiation is cooling the ocean not warming it. There is no way the back radiation can significantly warm the ocean directly by conduction or turbulent convection, so its role is limited to affecting the temperature of the air and thus the differential between ocean surface and air temperature which affects convective processes such as evaporation.
According to NASA’s empirical figures rather than Trenberth’s fictitious energy balance figures, radiation only accounts for around 25% of the loss of heat from the ocean, and the ocean itself is in control of the temperature and humidity of the atmosphere above it. Water vapour is nearly all of the ‘greenhouse effect’ and the convective transport of energy is the greater anyway. Therefore the degree to which a change in the net radiative long wave flux caused by a change in co2 levels can affect the rate of cooling of the ocean is small.
This leads me to believe that although the greenhouse effect is real, the variation of co2 is nowhere near as important as most of the mainstream climatologists think it is.
TB – The errors in that statement have been pointed out to you many times. Back radiation accounts for more thermal energy in the ocean than solar irradiation for all the reasons previously described, including those described in detail in the original Dragon Slayer thread.
In addition, you have again confused net IR effects with back radiation. The oceans absorb back radiation at an enormous rate (about 330 W/m^2). Because they emit even more (from the energy received by both solar and back radiated photons), they have a net IR deficit, but this does not mean that they didn’t absorb the energy in the first place.
If you reread the original discussions, or let other readers review them, the significance of back radiation will become apparent. There’s nothing wrong with doing that, but repeating the same fallacies without calling attention to the previous discussions is not a helpful way for anyone to understand what is happening.
Fred, That is kinda apples and oranges. Most of the solar absorbed by the oceans is between 30N and 30S where the percentage of land is less than 30%. So while the total solar absorbed by land and ocean is 51%, the portion absorbed by the oceans should be closer to 80% than 70%. I theorize that is why Earth can recover from glacial periods.
Pardon, that should be hypothesize since I am too lazy to pursue it.
The total absorbed from solar is closer to 33 percent, including the oceans. The total absorbed from back radiation accounts for the rest, and is also dependent on latitude, with more absorbed in the tropics than the poles (although the difference is less than with solar). Back radiation depends on air temperature, which is why it will vary from one region to another.
Of the solar input, Trenberth has 49% and NASA has 51% absorbed by land and ocean. Without that solar input there would be no LW out to create the LW in. Because of the ratio of land mass to ocean in the area of the equator, the ocean absorbs more of the 49% or 51% than the 70.8% ocean area would indicate. If you wish to consider albedo, the most reflective surfaces are at the poles which also have a higher percentage of land surface but still emit at around 255K.
I think this is kinda important to remember because a 1% increase of cloud cover in the tropics will have a greater global impact than in the temperate latitudes than many can determine from the cartoons.
Dallas – We’re talking about different entities. I was referring to the fraction of absorbed energy by the surface that is solar, and you to the fraction of solar that is absorbed at the surface. Even for the oceans, however, it won’t be much higher than 60% after you subtract albedo and solar irradiance absorbed by the atmosphere. See, for example, TFK Table 2b.
The estimate of Trenberth, Fasullo and Kiehl for oceans is that the absorbed solar SW is 167.8 W/m^2 and back radiation 343.3 W/m^2. Thus the solar is 33% of the total incoming radiation according to that estimate.
Fred, Yes, 33 % from solar with a net down of 1.3 W/m^2 (no net down over land?). Is that the part of the missing heat? This paper also has one of my favorite statements, “There is a TOA imbalance of 6.4 W/m^2 from CERES data… The TOA can probably be most accurately determined from climate models and is estimated to be 0.85 +/- 0.15W/m^2 by Hansen et. al. (2005)…”
The point I was making is that the majority of absorbed solar energy is in the oceans between 30N and 30S, That heat is transported poleward by atmospheric and ocean currents and a significant amount is stored between 10 and 100 meters below the surface. Outgoing IR and incoming IR are doing a battle as usual, but a significant amount of solar energy is stored longer term at depths and transported to land via precipitation. So it is kinda apples and oranges if you neglect the stored solar energy.
Fred, don’t you understand that it is the sun that warms the oceans not ‘back radiation’? The ocean’s mass is almost 2500 times greater than that of the atmosphere and its specific heat is about 4 times greater so your statements is utterly unphysical. Try heating up a cold bath of water with a pocket torch to get the picture. So please drop the back radiation BS.
John – Thanks for your comment. Solar radiation and back radiation both contribute to the heat content of the ocean, with back radiation contributing about twice as much as the solar contribution.
Consider a slice through the ocean a centimetre below the surface. The water below the plane radiates upwards into the water above, and the water above the plane radiates downwards into the water below the plane. The water below the slice is more than 100,000 times the mass of the top 1 cm, and the same thermal capacity. But if the top centimetre didn’t radiate downwards, then every layer of the ocean would be radiating upwards with nothing to balance it so fast that the oceans would freeze top to bottom in a matter of days.
The balancing downward radiation coming from throughout the bulk of the oceans can be considered “back-radiation”, although the distinction is somewhat artificial, (and it doesn’t explain the controlling mechanism of the greenhouse effect).
Fred, I think you are missing the point that a lot of the back radiation consists of energy the oceans already emitted, thus cooling. The contribution of ‘new’ longwave is in heating the air such that the differential between air temperature and ocean surface temperature is reduced, thus slowing the cooling of the ocean. But this is a smaller effect than the one you propose.
TB – The net IR flux is upward- i. e., in a cooling direction, as you state, which is why ocean temperature drops at night. However, there is substantial back radiation absorbed, day and night, and the back radiation in combination with a smaller quantity of solar irradiation during the day results in rising ocean temperatures averaged over the daytime hours .
Fred, The back radiation is absorbed in the first few microns of the ocean surface. The next millimetre or so is at a higher temperature, so the heat raised by back radiation is unable to propagate downwards by conduction.
In the open ocean, turbulent convection works much deeper down and doesn’t create surface eddies which create any significant vorticity which could ‘mix down’ back radiation heated water molecules.
Nearly all back radiation is re-radiated from the surface along with the IR derived from solar radiation heated water rising from the deep.
This means that the only way back radiation slows the cooling of the ocean is by reducing the air/water temperature differential. The fact that air temperature changes lag sst changes globally by 3 months suggests that this is very much a secondary effect compared to the larger convective processes (66W/m^2 net IR compared to ~80 latent heat and ~30 thermal conduction).
It’s not enough to explain the warming of the ocean 1980-1998. The reduction in tropical low cloud cover empirically measured by ICCP using weather satellite data is more likely responsible for that.
The Sun warms the ocean, the ocean warms the air, the back radiation keeps the air a bit warmer for a bit longer before the air loses heat to space.
Hi tallbloke,
I don’t believe this idiotic argument is still going. You are absolutely correct of course. I would be pretty sure the oceans are cooling at night.and warming during the day.
I am even willing to stipulate that if extra CO2 is added to the atmosphere the cooling is less.
This is one of the very simple ideas that eludes Fred. Deconstructing the passage below – it is all logic and linear language without any leavening of imagining
Perhaps if we talked about forward radiation? Or call it surface radiation? Being more than back radiative (as stupid as that idea is)? I don’t know – I gave up long ago.
Cheers
TB – The fallacies in your argument have been detailed in the original SkyDragon thread, which makes clear why back radiation contributes more to ocean thermal energy than direct solar radiation. The fallacy of “non-penetration” is a fallacy regardless of the multiple mechanisms by which the absorbed surface IR is translated into an increase in thermal energy at depth – this involves the diurnal convective cycle, turbulent mixing, and inhibited conduction and convection in general. Some of these mechanisms involve physical bulk mixing (which we know is substantial from the shallow mixed layer gradient), and some do not, but they all contribute to the thermal energy within the entire mixed layer and below. This entails actual warming during the daytime (via combined solar/back radiation effects) and reduced net cooling at night, even though absorbed back radiation remains substantial at night. I’m not sure why a mechanism that has been so well discussed earlier, and well documented by the measured fluxes and gradients, needs to be regurgitated here, but anyone interested can see my own contributions to the discussion in the original thread by searching for my name, and can also find links to relevant references that I won’t repeat here..
In a general sense, this is a non-issue, although in theory, some discussion would be justified as to how close the substantial mixing of solar and IR effects comes to 100 percent.
Another way to see the same thing is to consider the heating potency of the solar irradiance absorbed by the ocean at depths, which is in the neighborhood of 160 W/m^2. Those 160 W can only escape via the surface, but imagine, contrary to fact, that some mechanism existed that allowed 160 W to escape from a layer below and independent of a surface temperature of, say, 288 K (15 C) associated with surface IR radiation of about 390 W/m^2. What would the average temperature be at this depth if unaffected by the surface temperature? The SB equation tells us it would average about 230 K (-43 C, or 58 deg C colder than the surface). In fact, it tends to average only a few degrees cooler, depending on depth. From this we can conclude that radiation absorbed at the surface contributes an enormous amount of thermal energy to the deeper layers, and that this is independent of the mechanism by which this occurs. I can’t say whether this actual gradient might be even less if the mixing of surface and deeper energy were total (referring here to energy mixing and not to the physical mixing of water masses), but it seems clear that the two energy sources are well combined to cause the deeper waters to be as warm as they are despite the inability of sunlight alone to warm them to anything near the observed temperatures.
The quantity of upward surface radiation quite exceeds that ‘back rasdiation’ – although at a quantum level neither terms makes any sense.
Cloud cover changes caused most of ‘recent warming’ in both the oceans and atmosphere. Indeed there was relative cooling in the IR band.
John – I said above that the surface must warm up above Te, but that requires a mechanism. Back radiation to the surface from above is part of that mechanism. The entire mechanism involves the partial redirection of energy downward by virtue of the fact the IR photons impeded from escaping to space by increased GHG concentrations are absorbed by the additional GHG molecules. Some of that energy is subsequently emitted downward, leading to atmospheric warming and also surface warming. The mathematics are described by the radiative transfer equations applied to GHG concentrations and the relevant IR wavelengths. Without the redirected energy, the surface would have no way of knowing that energy was having any trouble escaping at higher altitudes.
Fred,
That is the standard explanation, but I don’t think backradiation is required to explain a warmer surface. I think everyone can agree the dT/dt (rate of temperature change) =K x delta T (man I have got to learn LaTex). In other words the rate of temperature change is porportional to the difference in temperature. If the temp of the atmospshere is warmer near the surface then the surface will cool at a slower rate. This is regardless of what causes the atmosphere to be warmer – GhG or adiabatic lapse rate.
The surface almost everywhere is warmer than the air just above it. How the surface warms as a result of increased GHGs may be complex, but back radiation is ultimately necessary for that warming to occur or be maintained. Without back radiation, the surface would inevitably suffer from an energy deficit (more out than in) unless its temperature cooled far below what it actually is. This is simply a matter of balancing the energy budget, which can’t be done from only absorbed solar radiation, but requires back radiation to account for observed surface temperatures.
This was where the Postma argument was fatally flawed independent of other considerations.
Fred, you are misrepresenting what Postma actually proves. He showed that the same energy output is achieved by modeling the earth with day and night and abandoning the fudged GHE equations whereby linear and non linear averages are incorrectly mixed.
He proves that by applying the same equations and adding adiabatic physics and the precise insolation offered by the inertia of night and day you get the same energy outputs with or without a GHE.
Thus:
Predicted earth emission without a greenhouse effect: 239 W/m²
Actual earth emission WITH a (supposed) greenhouse effect: 239 W/m²
John – What I say next is intended sincerely and not sarcastically. Postma’s arguments have been shown to be completely untenable in the previous thread, which readers can visit for the details. It is no favor to him for his name and opinions to be publicized further, because what he needs to do now is engage in some introspection, and then decide how to move beyond an effort that has failed and toward other contributions he can make to science. You are impeding that process by bringing him up in a new thread.
…And yet the earth’s surface is at a temperature of 15 C and is emitting 390 W/m^2. So, how is it that we only see 239 W/m^2 emitted into space? The only possible answer is that elements in the atmosphere are absorbing (or reflecting) some of the terrestrial radiation. They are what allow the earth’s surface to be at a higher temperature than -18 C (for which the surface itself would be emitting 239 W/m^2).
Your claim that the emission back out into space is always 239 W/m^2 is correct…but it’s a red herring. (It is simply what is required by energy balance.) That is what makes it sophistry rather than science.
The only thing that the adiabatic lapse rate does is set a stability limit on the lapse rate…i.e., if the lapse rate exceeds this, convection sets in and causes the lapse rate to drop back down to the adiabatic lapse rate.
Saying the adiabatic lapse rate causes the surface to be warmer is akin to saying that the centripetal force causes the earth to go in a circle around the sun. It is not really a causal explanation…It is more correct to say that the gravitational force is what causes the centripetal acceleration and thus the earth’s circular motion.
Back radiation is a nonsensical concept – http://upload.wikimedia.org/wikipedia/commons/e/e6/57911main_Earth_Energy_Budget.jpg
Net flux is all that matters from an energy perspective. If the atmosphere warms the net flux from surface to atmosphere declines and the surface warms.
You should try to get this right.
Robert – If you check the source of that diagram, you will find that it does not dispute the existence of substantial back radiation, but rather diagrams other elements of the energy budget. Back radiation is not merely a theoretical necessity to explain the Earth’s surface temperature, but has been measured by way of confirmation.
Oh Freddy – if you understood the diagram as approximating the flux of energy through the Earth system – you could move on to more rewarding areas of discussion. Only net energy matters.
The surface warms from the sun and loses energy in the IR to the atmosphere. It can’t be any other way. Your egregious errors on this have been patiently explained to you over months by better people than me and yet you continue ignore the essential nature of IR radiative flux in the Earth system – in that it moves in random directions within the atmosphere over a mean free photon path of about 50m – but on average out of the system.
I am sure this is not too difficult a concept for you – but as for now I must move on from an inconclusive dialogue that frankly I gave up on quite some time ago. Others have decided already on this – and you are very much in the minority.
What specific error did you have in mind, Robert? Please quote exactly a specific assertion I’ve made – don’t paraphrase – and then, if your patience holds out, explain what you find erroneous.
Back radiation (more formally “downwelling longwave radiation, or DLR) is a critical phenomenon in dictating the energy content and energy changes in the surface (land and ocean). It has been measured, and is a large quantity. Without the energy absorbed from back radiation, the planet would be much colder. The net IR flow is upward (in a cooling direction – approximately 60 W/m^2), as is necessary for balance, because solar irradiance is downward.
I believe you’ll find all of these points from previous comments I’ve made, including the very real existence of back radaition. If you think any one of the points is wrong, please tell us what you think is wrong with it, and what the right answer is.
Fred Moolten 8/22/11, 9:54 am, Planetary energy …
FM: Please quote exactly a specific assertion I’ve made – don’t paraphrase – and then, if your patience holds out, explain what you find erroneous. … Please tell us what you think is wrong with it, and what the right answer is.
That may be magnanimous and open minded, but it also sounds hauntingly like If I’ve left anything out, just ask me specific questions and I’ll be glad to answer them one by one, except for the part about answering.
This is a warning for Robert, aka Chief Hydrologist, specifically challenged by Fred Moolten in defense of the latter’s belief that back radiation is thermal radiation. Dr. Moolten doesn’t reveal what he is going to do with your response, but I have a test case.
On the “Towards sane policies etc.” thread, I quoted Dr. Moolten’s writing that ocean acidification [is] a very significant threat [due to] unabated CO2 emissions . I gave a lengthy, detailed response as to why that wasn’t true, how it came to be postulated, and how it is rooted in fundamental assumptions essential for AGW. 6/7/11, 12:36 pm. His response was,
FM: Jeff – I can see the medication isn’t working. 6/7/11, 12:58 pm.
At the core of Dr. Moolten’s misconceptions about back radiation and acidification is his belief in AGW (meaning, as always, a measurable human warming effect), and that colors all his writings. IPCC has had to discard, replace, and ignore physics and principles of science to fabricate its AGW story. It is an elaborate fiction built on a tissue of errors. Its dutiful supporters like Dr. Moolten inherit those errors. Those supporters don’t engage in rational debate because their position is a matter of belief, not science.
But Dr. Moolten is not unique. Here are a couple of recent examples.
On the Planetary Energy Balance thread, I gave a detailed critique on main points of the George Tech course EAS 8803 which Dr. Curry had recommended for background on radiative transfer. 8/20/11, 2:47 pm. Dr. Curry’s dismissive reply was,
No time to argue each of your points, but nearly all of them are incorrect. The Beer Lambert law applies only to monochromatic radiation, and hence the subscript lambda. You do not apparently understand the difference between a differential equation and its integrated form. Etc.
Her only point was wrong, as I detailed in subsequent posts. I gave a direct response on 8/20/11, 9:56 pm. I amplified it on the heels of Dr. Pirilä’s dutiful intervention to repeat the same, false AGW story sans Beer-Lambert, on 8/21/11, 10:46 am.
A dialog appeared on the Slaying the Greenhouse Dragon Part IV thread in which Pekka Pirilä relied on a automatic balancing in the atmosphere. Beginning 8/15/11, 4:44 pm. It culminated on 8/16/11, 10:42 am, with my extensive quotations from Pekka Pirilä’s writings with counterpoints to argue that equilibrium and balance do not exist in the atmosphere, so require an assumption from physics. He turned the dialog off:
I have often difficulties in following your reasoning. This time I fail completely. I really don’t find anything relevant from your message. That much I understand that you try to argue against me, but that’s as far as I get. I don’t know, why you accuse me of those faults in argumentation that you list. 8/16/11, 10:48 am.
A pattern exists in these sample responses from AGWers that no one need characterize. It has the effect when the going gets tough of quashing scientific inquiry. This behavior prevents dialog from converging on knowledge.
An interesting post, Jeff.
To a large extent, I agree with the sentiment that you express. However, I also find your selection of examples to be rather ironic (note to the Chief – from a perspective of a descriptivist, irony need not be intentional – have you gotten the difference between descriptivism and prescriptivism straightened out yet?):
Now you haven’t ruled out the possibility that the characteristics that you point out are exclusive to the responses of “AGWers,” but I will “infer” that is what you were thinking (heh!). I will further “infer” that you see some causal relationship between being an “AGWer” and a proclivity for writing responses of the character you describe.
Could you please confirm whether my inference is correct? Because if it is, I would like you to re-evaluate. I can see a slew of responses from non-“AGWers” that equally fit the description you have outlined in each and every post since I have arrived at this website. In fact, I could find many in each and every thread from non-“AGWers” that are arguably far more illustrative of the characteristic you describe.
Jeff – please see my incorrectly nested post (1:06) immediately below.
Freddy – I think it is quite clear the direction of net energy flux through Earth systems. You are specifically wrong in making a distinction between upwelling and downwelling IR radiation. It is incorrect to make this distinction – and then to ignore the upwelling component is to compound the error.
The physical interpretation is that IR radiation moves in all directions with a mean free photon path of about 50m – with a net upwelling for reasons that involve the 2nd law of thermodynamics.
Now this has been said repeatedly to you – I said it yet again as simply as I could. Yet you insist that that I need to be more specific? The surface warms with sunlight and cools predominantly by radiating in the IR band. I have stipulated that the cooling is less with a warmer atmosphere.
It is simply a more correct physical interpretation of radiative flux. I don’t intend to continue this discourse – as it has been done to death and if you cannot understand yet the distinction – so be it.
The physical interpretation is that IR radiation moves in all directions with a mean free photon path of about 50m
CH, how are you weighting this: by number of photons or by their energy? And up to what altitude (since it’s easily shown to be far greater than 50m if you don’t set an altitude limit)? And are you assuming dry air, 2% water vapor, or something in between?
(Only asking because it would be a waste of time fact-checking this without the relevant parameters.)
Robert (Chief Hydrologist) – I think readers who review these recent exchanges will conclude that you have so far ducked the questions I asked. One of the reasons I asked you to quote me verbatim rather than trying to paraphrase.me is that I was (and am) confident that all the points I’ve made are correct, and that only by paraphrasing them in a way that misrepresented them would make them appear incorrect.
,
I’ll repeat my invitation, however. If you can quote verbatim – without paraphrasing – assertions I’ve made that you think wrong. and indicate exactly what you find incorrect about them, I hope you’ll do so, to permit readers to judge these issues. Otherwise, I am content to let all my points stand on the importance of back radiation to the Earth’s energy budget.
Back radiation is an important concept, and so it’s worthwhile for us to get it right, just as it’s important to understand IR radiation as a two-way process in which upward IR exceeds downward IR.
Vaughan,
The mean free photon path for IR obviously varies from centimetres to kilometres. I read a number somewhere of the average length being 48.8m
If you have a better number – let me know.
Cheer
Freddy,
I don’t know how much more specific I can get. Back radiation is a non-physical concept – only net radiative counts in energy transfer. You need to include the statistics of flux to make any physical sense of energy fluxes through the system.
It is just the way it is – you have had this discussion with many here and further dissembling with me will not assist.
Robert – You say you don’t know how you can be more specific. I’ve explained how several times, but I’ll repeat it here. If you believe you’ve identified an error in my statements, please quote verbatim, without paraphrasing, a statement you disagree with, explain what you believe the error is, and describe what you believe is the correct statement.
I think readers will notice that you have repeatedly declined to do this. I conclude, at least tentatively, that you realize you are wrong, but refuse to acknowledge it. In fairness, though, I want to keep my invitation open for you to quote me verbatim and then discuss what you perceive to be errors, so that readers can judge the issue.
Back radiation, which is substantial and has been measured, is an important variable in climate dynamics because of its contribution to the thermal energy of land and oceans. Upward IR radiation is of course equally important, as is the difference between them – the net IR radiation, which is upward at about 60 W/m^2, and thereby helps to balance incoming solar radiation. Merely knowing the latter 60 W figure, however, is inadequate for a full understanding, because it is equally important to realize that it’s the difference between two large fluxes with different sources and destinations, and to know how each flux originates and the temperature with which it’s associated.
Freddy,
You keep banging on about back radiation – for months now with various people and I can’t see that it progresses at all. I only persist because you mislead others with this persistent error.
Net IR is outward – although IR is emitted in all directions over a realtively short distsance – and cannot possibly be heating anything on the surface as net IR is negative at the surface. All of the heating at the surface is in the SW. Adding CO2 to the atmosphere slows down cooling and energy and heat builds up in the total system.
If you cannot see for whatever reason that this is better physical description of the system – after some months at this – I cannot help. Your specific error is that back radiation is an irrelevant and unphysical understanding of radiative flux. You simply continue to insist that it is an important consideration. Allow me to disagree.
Moreover – you have ‘tentatively’ raised the question of bad faith – I don’t appreciate that at all.
To once more invoke a phrase, Robert, that I’ve felt was appropriate on other occasions, you don’t lose gracefully.
CH, you have to admit upwelling and downwelling IR have completely different and distinct spectra, and are therefore the result of different emission sources. Specifically at the surface upwelling is dominated by ground emission, downwelling is dominated by sky emission (with no ground signal). Net is a useful concept, but certainly not the basic one.
Freddy – I haven’t lost anything at all. If you will insist on nonsense I will call it such – despite your pompous insistence on getting the last word in any discussion. You are wrong and can never admit to anything of the sort.
Jim the nestijng is getting too confusing here – http://judithcurry.com/2011/08/22/can-we-make-good-decisions-under-ignorance/#comment-103501
The mean free photon path for IR obviously varies from centimetres to kilometres. I read a number somewhere of the average length being 48.8m. If you have a better number – let me know.
Absent any obvious choice for the wide range of very influential parameters, I’d say there wasn’t a single good number. All there is is a complicated function of all those parameters, and a mfp given to three decimal places is wishful thinking.
One interesting datapoint might be the average when weighted by energy (as opposed to photon count) for horizontally directed radiation at sea level assuming STP and 400 ppmv CO2 in completely dry air. But even in the horizontal case one must truncate, otherwise the photons that escape to space will drive the average to infinity.
What one can meaningfully ask is the mean free path of a photon at sea level within 0.07 /cm of the strongest CO2 line. I calculate this at about 4 cm. At ground level on Venus (there is no sea) it would be way less than that.
I have to say I’m on Jim D’s side on this Moolten-CH argument:
CH, you have to admit upwelling and downwelling IR have completely different and distinct spectra,
While my Dragonslayer-iv post may have given the impression I was on CH’s side, my goal there was really just to point out that the DLR/back-radiation view of things could be overstated a la Alistair Fraser. Judging by the strong reactions it was clear that this point needed making.
CH’s net-radiation view is valuable for insight into the global energy budget. Absent clouds, for sites near sea level, net upwards flux oscillates between 100 W/m2 and 60 W/m2 from day to night. With clouds it drops pretty much to zero, but rarely goes significantly negative. These are important insights when reasoning about the global energy budget.
Fred’s focus on DLR and ULR separately is important in understanding the behavior of ULR – DLR (net upward flux). In a dry clear sky, the 40 W/m2 swing of net flux between day and night is due largely to the diurnal temperature variation of the surface, with the DLR remaining relatively constant. Clouds change this by increasing DLR dramatically while reducing the diurnal swing of ground temperature, with the result that ULR and DLR stay close together, thereby minimizing net upwards flux
What I find really interesting is how ULR hardly ever drops below DLR. It is as though the net upward flux was fixated on preserving the second law of thermodynamics. Buried in the pandemonium of trash talk in the G&T paper is the important point that heat flows from the surface to the atmosphere, not vice versa. Judging by the net flux data they at least got that right.
The bottom line for me is that I see no future in the continued debate between Fred and CH. Both have sound logic on their side, and as long as each refuses to acknowledge the soundness of the other’s logic that debate cannot end.
I wish I could say the same for Arfur Bryant, who needs to tone down his 23rd century logic if he expects those of us still working with old-fashioned 20th century logic to follow his reasoning, which I for one find nothing short of magical.
One thing I forgot to say in my account of the separate variation of ULR and DLR is that, while it shows the value of considering them separately as well as together (as their difference), it does not in any way support the statement that the atmosphere heats the ocean twice as strongly as the Sun. I took strong objection to Alistair Fraser’s statement to that effect in my recent post on that subject (which Judy renamed to “Dragonslayer-iv”), and Fred is no better on that score. (Not just one but two people wrong on the Internet, what is the world coming to?)
The problem, Fred, is that you are completely ignoring the fact that the ocean radiates heat upwards to the atmosphere. Hence to say that the atmosphere adds twice the heat the Sun does to the ocean is as illogical as saying that so many people walk into Macy’s every day that it will eventually explode under the pressure. Would you base your net worth on four decades of accumulated salary while ignoring expenses?
One has to look at these things from an equilibrium perspective, and ask whether the equilibrium is being disturbed, and at what rate. Absolute numbers considered in only one direction are meaningless.
Vaughan – The basis for the statement that the DLR contributes approximately twice as much as solar to ocean temperature can be found in the TFK energy budget diagram plus the comments I’ve made to Tallbloke elsewhere in the thread. The fact that the ocean radiates IR upward and that the net IR flux is upward in not really relevant.
The basis for the conclusion resides in the magnitude of the solar flux vs DLR combined with the evidence that the upward IR flux is a response to both the solar and DLR component, and cannot be explained as a response to the DLR component alone. There may be a slight uncertainty as to whether the solar and DLR thermal energy are 100% mixed in contributing to upward IR, or less than 100%, but the ocean thermal gradients indicate that the energy mixing is very substantial. As I mentioned to Tallbloke, this will occur regardless of whether there is bulk mixing of water masses between the surface and lower layers, although there is good evidence for a bulk mixing role – particularly involving the diurnal convective cycle.
Fred Moolten is completely wrong about IR energy being mixed into the ocean. See my post here for the correct explanation of th eGHE:
http://judithcurry.com/2011/08/19/planetary-energy-balance/#comment-104533
Joshua 8/22/11, 12:53 pm, Planetary energy …
J: Now you haven’t ruled out the possibility that the characteristics that you point out are exclusive to the responses of “AGWers,” but I will “infer” that is what you were thinking (heh!).
One of the reasons I didn’t actually point out those characteristics was to avoid any implication that they were exclusive to responses from AGWers. Maybe I was wrong, though, when I said “no one need characterize”. Some of the characteristics I had in mind were the overlapping qualities of arrogance, dismissiveness, evasion, and personal attacks (ad hominems).
J: I will further “infer” that you see some causal relationship between being an “AGWer” and a proclivity for writing responses of the character you describe.
My intention was to be explicit about that causal relationship. Applying just a little science, AGW becomes indefensible, yet the AGWers are committed to the movement, and ultimately to defending its errors. If you get too specific with them, they bail.
Those characteristics are certainly found in posts from others. The AGWer pattern is just a spectrum, not a lock. Other posts have a background of white noise in which no part of the spectrum is empty. Much of the white noise comes from the posts that qualify as tweets. Others yet also have coherent noise, as when dialog pursues the mechanisms by which back radiation warms the surface; or how close to an adiabat the atmosphere is, must be, or tends to be; or how to get radiative transfer just right; or what name to call the greenhouse effect.
The spectrum of the others often mimics that of the AGWers, probably intentionally. But the post fails on arrogance when a little check shows the poster had no standing to be arrogant. Dr. Curry’s policy, much to her credit and doubly so, being unique among AGWers, is to moderate almost negligibly. Let a million flowers bloom. She gives hope if not convergence. The result is much like the Internet. Caveat emptor.
In a dry clear sky, the 40 W/m2 swing of net flux between day and night is due largely to the diurnal temperature variation of the surface, with the DLR remaining relatively constant.
I’d better quantify “relatively constant” in the case of a clear sky or I’ll be in trouble. During the day DLR increases along with ULR but only by half as much, on the order of 30 vs. 60 W/m2 variation respectively, whence net upwards flux variation is approximately equal to that of DLR, namely 30-40 W/m2. Throughout the night DLR and ULR decline at roughly the same rate, so that net upward flux remains constant.
The ambient flux at the surface on a clear day, defined say as the average of DLR and ULR at the surface is way bigger than the net upwards flux, 350-370 W/m2 vs 70 W/m2. Clouds have negligible impact on ambient surface flux but bring the net upwards flux down to near zero. One might expect lapse rate to knock 20 °C off a cloud bottom at 2 km, but this is offset to some extent by the warming effect of condensation.
And btw, Jeff,
In case you haven’t yet “inferred” my “implications” behind my last post – let me make my implications more concrete (so there will be no mistake due to incorrect inferences).
The selectivity of your criteria for choosing your examples helps to explain the basic reasoning for why I couldn’t see validity in the conspiracy between widely diverse entities dispersed widely over the globe, across disciplines, that spanned widely divergent stakeholders, and among people for whom there is no logistically realistic infrastructural connections – as you outlined in our previous exchange of ideas.
Very interesting claim. I have made a copy of this link.
Could you possibly be that naive? Or . . . . .
Here is the reason Joshua,
Psa 2:1 Why are the nations so angry? Why do they waste their time with futile plans?
Psa 2:2 The kings of the earth prepare for battle; the rulers plot together against the LORD and against his anointed one.
Psa 2:3 “Let us break their chains,” they cry, “and free ourselves from slavery to God.”
Psa 2:4 But the one who rules in heaven laughs. The Lord scoffs at them.
Joshua 8/22/11, 1:06 pm, Planetary energy …
J: The selectivity of your criteria for choosing your examples helps to explain the basic reasoning for why I couldn’t see validity in the conspiracy between widely diverse entities dispersed widely over the globe, across disciplines, that spanned widely divergent stakeholders, and among people for whom there is no logistically realistic infrastructural connections – as you outlined in our previous exchange of ideas.
Case 1: Fred Moolten solicited specifics from Chief Hydrologist, as if Dr. Moolten would answer specifics. But evidence shows (a) Dr. Moolten doesn’t answer specifics, and (b) that he is not unique among AGWers posting on Climate Etc. in not answering specifics. My examples were not selected as biased evidence for some conclusion or other. Each example, one from Dr. Curry and one from Dr. Pirilä, was sufficient proof that Dr. Moolten was not unique. 8/22/11, 12:36 pm, Planetary energy … thread.
Case 2: Askolnick cited Muir Russell’s Report as evidence that Mann et al. had been cleared of conspiracy, and repeating what Dr. Shore had urged, that skepticism about AGW was impliedly a conspiracy of the right wing. The points I tried to make were (a) Mann et al. provided evidence of a conspiracy to defend his Hockey Stick reconstruction and to bias peer-review, a conspiracy that was successful. Moreover, the Hockey Stick was but on of a collection of small conspiracies embodied in IPCC reports (details on request). (b) The right wing is a collection of small, diverse movements sharing but one tenet – small central government, which is per force anathema to the AGW movement, now an open tenet of the left to expand the role of US Federal Government while restricting its autonomy to resist through international agreements. 8/19/11, 10:08 pm, 12:27 pm, Slaying … thread.
I don’t see how (1) illuminates (2) in any way, and specifically not in biasing data through selectivity.
Jim – it is something I am wondering about – http://judithcurry.com/2011/08/22/can-we-make-good-decisions-under-ignorance/#comment-103501
The fact that the ocean radiates IR upward and that the net IR flux is upward in not really relevant.
Mathematically speaking, you’re quite right. Physically speaking, the mathematical fact you allude to has no sensible physical meaning.
If it did, a similar argument would allow you to prove that diffusion transports a hundred times more air than a 5 m/s breeze passing through a hula hoop from left to right. This is because air molecules flow through the hoop at 500 m/s. If you only look at the air molecules that flow in the same direction as the breeze, it is clear that 100 times as much air is being transported by diffusion than by the breeze.
Now from your perspective this factor of 100 is in fact the case, the way you’ve defined things. You choose to neglect the molecules that flow the other direction, and you end up with an amazing conclusion.
Replace air molecules by photons and you have precisely your argument that the atmosphere heats the ocean twice as strongly the Sun. You arrive at this remarkable fact by refusing to include the photons rising up from the ocean in your calculation.
Your math is just fine, your physics lacks a certain intuition about what’s really going on there.
Fred,
Yes I think you’re right about the lapse rate not being an ‘alternative’ to the GHE but at the same time it doesn’t mean there is no back-radiation either.
Isn’t it just a case of looking at a problem in two slightly different ways and coming up with the same answer in each case?
Mr. Fred Moolten, How would you feel about GHA or “the greenhouse affect”?
Hence the difference between the blackbody temperature (Te) and the actual temperature at the surface (To) could possibly be explained simply by the fact that most of the outgoing radiation is actually occuring at an elevation of about 5km if I’m not mistaken.
Sorry, John, I’m not following your arithmetic here. A lapse rate of 10 °C/km and a nominal surface temperature of 288 K implies a temperature of 288 – 5*10 = 238 K at 5 km, about 17 degrees below Te. How do you reconcile your arithmetic with mine?
The mystery to me in the Postma discussion why is there the preference and vitriolic defence for the ultra-simple zero-D model the earth with uniform insolation and emission. Until this week, I had no idea such a simple model was in use beyond he first day of academic study and the first chapter of a text book. What is the purpose of the zero-D model’s except to show that a GHE must exist?
I thank Postma and Judith for posting it for discussion for bring this to the fore. We are dealing with a very non-linear system. Postma’s model is as simple as we should consider: to me that is clear as night and day. Postma’s conclusion that GHE is unnecessary is not unsupported,
I discussion of a relatively simple model of a rotating “buckyball” with a day and a night might be a more reasonable simple model of energy balance. You I think you have only 5 unique surface orientations, rotated in 12, 18, or 24 discreet time periods on an axis through opposite vertexes , with water, land, or ice/snow as the surface. It is certainly more complicated than the zero-d model, but this is easily done in one small Excel worksheet.
I would be surprised the buckyball model has not been done before. Regardless, discussing energy balance in this non-linear model would be more productive than the arguments that solar insolation should be divided by 4.
Stephen,
Who has defended that model vitriocally?
Everybody has told that it’s not a valid model of the atmosphere, not even close to a valid model.
It’s only a toy educational model to explain with minimal prerequisites, what the GHE is.
The Postma thread established for me that the zero-D model is too much of a toy to explain “what the GHE is.” In the nearly 1200 comments, a large proportion of them maintain the “toy” is good enough. Why such an effort to defend the toy?
Whether it’s enough or not, is really a matter of taste. That model is not a model of the atmosphere, but it describes what happens in a system that is possible to build. (A structure built from the back pane and a window placed in empty space outside the atmosphere and illuminated by solar radiation. It’s a correct model for such a structure.)
There you go with another defense of the toy. My skepticism grows with each attempt.
The Masque of the CAGW Death.
==========
My skepticism grows with each attempt.
Stephen – Maybe this sounds arrogant, and maybe it is, but those of us who understand climate physics principles are already aware that the greenhouse effect and back radiation are inescapable realities, and we also understand that a small number of individuals will refuse to accept those realities no matter what we say. You may be among those individuals. In that case, we have no hope of convincing you, but neither do we care very much. Your level of skepticism is your problem, not ours.
There are others who call themselves skeptical who raise legitimate questions about our current understanding of climate change. We are generally happy to engage with them so as to explain why we arrive at the conclusions we hold. They are a different bunch, and deserve a different level of attention..
Fred, you are right… it does sound arrogant.
But also true.
Indeed. ¨This problem which takes most people 10 years to learn doesn´t make sense to me, and someone can´t explain it good enough on a blog; I am skeptical!!!¨ sums up most people´s ¨skepticism.¨
Fred – I’m going to have to break this up as the spam-catcher got hungry. If you’re interested – this will take a few posts in segments:
Here’s what I find interesting about that. It would seem to me that if you really didn’t care, you wouldn’t spend so much time interacting with folks as you did on the Postma thread and the Dragon Slayer threads. I think that there’s more there than meets the eye (although I don’t have a handle on what that might be).
I am fascinated that folks like you and maxwell and Pekka and Judith will say that the ideas of someone like Postma are complete non-starters – yet you spend a lot of time engaging with them in a very complex dialogue.
What’s also interesting is that in not being able to evaluate the veracity of the different technical arguments, all I can do is try to get the “gestalt” of the various opinions. Usually, when doing that in technical areas I’m not equipped to understand, I can usually get a feel for when someone delivers a knockout punch. (As an aside, it is almost never when someone says to someone else that their ideas are idiotic or some such characterization.) There’s usually a “tell” of some sort in someone’s response if their interlocutor has dealt a death blow. I think that the closest I could find was when Postma wouldn’t answer Judith’s challenge to test his hypothesis by applying it to the climatic dynamics of other planets.
Part II:
So, not that my opinion really matters, but for what it’s worth, I find that dismissing someone else’s knowledge base – when from all I can tell they seem to display a grasp of a variety of relevant concepts (of course, admitting that I am susceptible to being fooled by someone who talks a good game but presents only shells of arguments – as was asserted about Postma) – backfires for me as an observer. Given that there are more than likely only two kinds of “participants”: expert combatants on each side who demean the expertise of the experts on the other side, and observers who don’t have the requisite expertise, based on my reaction, criticizing someone else’s expertise as an explicit discourse does not have any benefit:
1. The “criticizer” already feels that the “criticized” lacks expertise. Saying that they do will change nothing.
2. The “criticized” will simply reject the criticism of the “criticizer.”
3. If they’re like me, seeing one expert criticize someone else who (at least to my ability to understand) seems to possess a fair level of expertise, only reduces the credibility of the “criticizer.”
Sorry – for that rambling mess. When I started the comment, I didn’t expect it to end up where it did.
Part II:
So in the end, all I’m left with is trying, somehow, to assess the credibility of the players in the game. Also, I can hedge my bets by looking at which side seems to have accumulated the preponderance of expertise.
Given that there are more than likely only two kinds of “participants”: expert combatants on each side who demean the expertise of the experts on the other side, and observers who don’t have the requisite expertise, based on my reaction, criticizing someone else’s expertise as an explicit discourse does not have any benefit:
1. The “criticizer” already feels that the “criticized” lacks expertise. Saying that they do will change nothing.
2. The “criticized” will simply reject the criticism of the “criticizer.”
3. If they’re like me, seeing one expert criticize someone else who (at least to my ability to understand) seems to possess a fair level of expertise, only reduces the credibility of the “criticizer.”
Sorry – for that rambling mess. When I started the comment, I didn’t expect it to end up where it did.
I do certainly wonder every now and then, whether such discussions are of any value, or why I continue those. Sometimes they help in finding most direct ways of looking at the issues being discussed. Sometimes there’s the thought that some readers might learn something from that. What has become clear is that the most stubborn people never admit anything. They usually repeat their arguments as before independently on the number of times they have been proven totally wrong and the number of people, who have done that.
Joshua,
A lot of us who argue on the blogs may do so to try to educate people, while some just do it because it may be a fun thing to do in spare time, or are argumentative, or simply hate when they see wrong things on the internet. Ever see this image?
http://blog.pauked.com/wp-content/uploads/2008/02/duty-calls.jpg
No one is going to pretend that people who know the science better are necessarily much better off in choosing their battles. I’m terrible at it. The idea sometimes get lost too that there are thousands of scientists you never heard of, who don’t comment on blogs, who don’t read the blogs, etc who are out there publishing. This is why lists with a couple dozen names on it of “people skeptical of AGW” sometimes look impressive.
That said, the arguments we get into on blogs generally do not at all reflect what scientists actually debate about. Sometimes perspective is lost on where the science is very solid, and where research needs to be done, since the topics discussed in the literature are generally a complete 180 from those discussed here and elsewhere (Isaac Held’s blog may be a good example of getting a feel for where the “up to date” questions lie).
Chris – yes I have seen that cartoon. Unfortunately, so has my girlfriend.
I think that your point about mistaking the blogosphere for some scaled-down version of reality is on point. In reality, the blogosphere is a very distorted little world (thank god). It’s a mistake to think that we can extrapolate, proportionally, from the blogosphere to the larger reality.
Held’s blog is way too technical for me.
Hi Joshua – I think the answer to your question, for me at least, is that when I address Stephen (or some other individual), I have a much larger audience in mind, including other participants in these threads as well as bystanders. Even if I can’t convince a particular individual of a certain conclusion, I can make clear that I find enough evidence to have been cited for open-minded readers to come to the same conclusion themselves – either because they visit the evidence or respect my ability to interpret it.
Regarding the “numbers game” as to how many skeptics believe the GHE to be non-existent vs those with some other view, I’ll confine the topic to people who are familiar with the description of the GHE, excluding lay persons who are merely vaguely familiar with the concept of AGW. I don’t know the answer, but counting blogosphere responders may not be informative. Anyone can compile a list of those who volunteer their opinions, but what does that mean?
I’m reminded of the Dover, PA trial a few years ago involving the teaching of creationism/intelligent design. The ID proponents circulated a list of a few hundred scientists purported to endorse ID. In turn, the defenders of evolutionary theory produced a list of scientists who supported evolution. At the time, it was a few hundred but has since grown to more than a thousand.
One interesting feature of that list, though, was that it didn’t refer to scientists in general. The list consisted only of scientists whose first name was Steve (in honor of Stephen Jay Gould).
Google “Project Steve” for more on this.
But Fred – what I was saying was that as a bystander – denigrating the expertise of someone who, for all I can tell, seems to possess expertise, is ineffective. Of course, I may not be a typical bystander – but unless I’m already inclined for one reason or another to trust your expertise over someone else’s, when you denigrate someone else’s expertise, it is ineffective. And if I’m already inclined to trust your expertise over someone else’s, then I’m not an objective bystander, and all I’m doing is looking to confirm my bias – something I’ll do whether you criticize your interlocutor’s level of expertise or not. I see no equation where you come out ahead via that level of discourse.
As opposed to reading you denigrating the expertise of your interlocutor, I find it more effective when you do as you just describe – lay out your argument, provide resources for those interested in researching the questions in more depth, and explain that based on your level of expertise, your combatant’s argument isn’t consistent with the facts, logical, etc. I’m thinking of the ocean acidification thread in particular, when you stated your reasoning, offered your opinions, and let Willis et. al. hand-wave about hand-waving.
Joshua – You make good points. I think it’s worthwhile for each of us to try to establish our credibility through reasoned arguments. When we read the same fallacies offered over and over again, we face a dilemma. At what point do we stop repeating the evidence and either dismiss the claim or simply ignore it. Since we don’t really have much feedback on the effects of our choices, it’s hard to know, but your comments are helpful.
My sense is that we (or at least I) will sometimes err on the side of dismissal when we should merely have ignored the comment or linked back to earlier discussions of the evidence.
I think that in the case of “debates” such as this to prepare a really strong canned response which addresses the standard contra arguments and just repost it each time a non original objection is raised.
For original “Galileo” thinking you might have to think a bit…
Rattus Norvegicus, your answer here is the same answer I would offer. Indeed, that’s why I encourage people to examine Postma’s paper in detail and come up with a clearly defined and explained refutation. If you can find a contradiction within Postma’s paper which invalidates his conclusion, you have your canned response.
It obviously won’t convince everyone, but it will convince most people.
Brandon,
I think most people already have been convinced that Postma has nothing to offer, and so far I’ve seen no objection to my SkS counter-arguments. You claimed it was not good enough, but I showed while his whole geometrical reasoning was both a strawman and wrong. I don’t know if there is a step you are missing from his paper, to my response, to you, but there’s very little left to say about it. It wasn’t even wrong in the sense that serious scientists would sit down and think about it, as is the case for some of the “better” skeptics like Lindzen, where it actually takes a few years to re-work the results, check the data, etc; in this case, the issues are just on the level of an undergrad getting his homework wrong and the professor needing to correct him. In this case, the “professors” have been a good amount of people, and the student refuses to listen. At that point, there is no need to bother with it. A rebuttal was unnecessary in the first place.
You might not like the answers anyone gives you, or even understand them, but there’s a lot of interesting things to be skeptical about that all involve accepting that a greenhouse effect exists.
Chris Colose, I now see I misread one of your comments, and thus my response was off-base. I basically misread your comment as saying you spent half of your piece showing how the correct calculations are done. Naturally, my response makes no sense because you actually said you spent half your piece providing clarity on the fact Postma’s entire geometric reasoning was wrong. I apologize for misunderstanding you.
However, you are still wrong. In your section about geometrical reasoning, you barely even discussed his position. Your second paragraph is the only one which actually says his reasoning is wrong (and it was only two sentences). Your next two paragraphs were far more lengthy, but they contribute little. Basically all they say is Postma’s argument is an argument against a simple model when more detailed models exist.
The problem with your piece is you never tie your criticisms to any conclusion. You say he’s wrong about certain things, and then you move on. You don’t discuss what the impact of your claim is. You don’t show any mistakes you mention actually invalidate his conclusions. If you want to refute someone, you have to show the impact of the error or errors you found actually invalidate his or her claim. You didn’t do that.
Brandon,
I find it interesting that you fail to account for the fact that in his 40+ page manifesto that Postma ran off the railis in his analyis around page 10 where he attempted to justify doubling the average TOA insolation. Once I got to this point I just couldn’t continue, pencil in hand to check his math or not. This error is so severe that continuing, IMHO, was not worth my time. Please justify for me why this assertion (and assertion is all it is when dealing with a model which deals with averages) is correct.
Rattus Norvegicus, I’m not clear on just what assertion you want me to justify. Could you be a little more specific? Also, could you make sure whatever assertion this is is one I actually support?
Hey Josh, read Chris Colose’s and the rodent’s responses above. See what I mean?
The non-linearity in the effect of heating water means Postma has a point, but his thesis is rejected in it’s entirety because They don’t understand how non-linearity makes averaging a blunt instrument.
Tallbloke –
I concede that you may have a point, but may is the operative word there. Not having a technical background, I can’t tell if a fatal flaw has been identified as “They” claim.
I’m left to weighing your claims of better understanding of the physics against “Their” claims of better understanding of the physics. And that’s where your aforementioned facile conclusion (I could list others, if you’d like – think Lord Monckton and Nazism) doesn’t improve your standing.
What I continue to find interesting is that usually in these kinds of situations I can “grock” a debate well-enough to get a sense for who’s blowing smoke. As I said above, usually there’s a “tell,” or some basic structural logical flaw that is visible. The online equivalent to a change in breathing pattern or a falsely confident smile. I’m having a hard time doing that with the Postma thread and a few others – except in a few obvious spin-off convos like when Claes obviously mischaracterizes something Judith says or accuses everyone and their uncle of only agreeing with Judith because they must be her students.
I think in part it’s because this material is so complex and so esoteric and involves so many unknown variables that it is easily possible for smart and knowledgeable people to full believe in completely contradictory viewpoints. But I think that more likely the biggest influence is the politicized nature of the debate – or to go into the political aspect more deeply in a psychological sense, the whole component of “motivated reasoning,” which can include the personal and/or psychological drivers that lay beneath the political ones. Thus, reasonable and knowledgeable people can successfully pull off what looks like a viable argument because they really do believe it at a conscious level – with their unconscious is working in the background to adjust their reasoning so as to overcome logical or factual disconnects in their arguments – because their unconscious is really driving motivations and goals.
So that’s why I go back to looking at how people’s perspective is grounded in their larger sociological constellation. That’s how I can get a better sense of their deeper driving motivations. When I see “anti-consensus” combatants arguing against a theory that would refute the effects of GHGs – that’s to their credit because they’re going against what would be, at least in some ways, their sociological motivations. But even below sociological motivations lie the psychological motivations – for example, more important than “tribal” motivations could be the personal motivation to be the “smartest” skeptic – leading someone to reject other skeptical theories even though the sociological goal of attacking AGW is shared.
But then, in that regard, another “tell” for me is when people flat-out deny the overwhelming role of “motivated reasoning” for everyone involved in the debate. That’s where Judith’s position looses weight in my book. I am very sympathetic to her focus on quantifying uncertainty – but when she then turns around and expresses absolute certainty about the role of politics in the debate, or when she fails to accurately describe the arguments of combatants on one side of the debate or the other, I can’t accept it when she says that the ideas of someone like Postma are a non-starter because of their poor grounding in foundational physics.
More of a response than you expected from your short comment to me, I’m sure – but you should always be careful what you ask for, eh?
Maybe my response was so long I should just summarize:
Whenever I see someone ranting about the conspiracy amongst the “climate establishment,” I can’t take anything they say about basic physics at face value – in that they demonstrated that they, themselves, believe in something that defies the basic physics of how the political world works.
Josh, presumably you feel the same about people who rant about scientists being ‘paid shill’s of Big Oil’ etc?
I got to the same point and had to work it out as a sanity check. The deal is that in his mindset, you have to think about the non-linearities in the effect and the instantaneous nature of the path to a steady-state.
Say that the daily temperature, T, goes as T=T0*(1+k*sin(wt)) oscillates about some value T0 with a daily period. This models a day-to-day heating cycle. The SB law goes as T^4 so that if we average this cyclic value over one day, then the radiation is increased to first order by 3*k^2 from the stable T0 value (easy to do the integration). So according to Postma’s theory and what parameters he says are required, the T0 temperature is about 300K and the upper excursion is about 360K, so that k=0.2 and the radiation increase is 3*(0.2)^2=0.12 from the average.
He then says that these temperature excursions aren’t actually measurable but that they exist in some state obscured by going into latent heat, evaporation, and convection in the macro case, and intramolecular degrees of freedom in the micro case, in his words.
So this is the non-linear averaging of some instantaneous variation of the Stefan-Boltzmann law. The higher temperature excursions produce much higher radiation so that an overall higher equilibrium temperature is achieved.
So I think I understand the rationale for his reasoning but his round-about way of showing this does not jive with a calculation. The temperature excursions required are just way too large. The oceans show virtually no change from day-to-day, so that the 3*k^2 would be completely buried in the noise.
Yep, very arrogant.
The Toy (Pekka word, not mine): (A structure built from the back pane and a window placed in empty space outside the atmosphere and illuminated by solar radiation. It’s a correct model for such a structure.) and with such a model with known solar insulation, average ground temperatures and average emission, you CAN prove a GHE is necessary.
Ok, but is such a uniform temperature Toy model an adequate stand in for the Earth: a rotating planet, illuminated on one side, with oceans, with large amounts of water existing in 3 phases (with heat of fusion, heat of vaporization), heat sinks and buffering of oceans and land, and N2,O2, Ar atmosphere of specific sea level pressure and a surface temperature range from -89C to 58C? I’m doubtful. Based upon my doubt, the Toy does not prove a GHE on Earth.
Mind you I believe the Earth does have a GHE; the Toy just isn’t proof. Postma says, “Look, with my model, I can make liquid water without any GHE. I even need a mechanism to cool the dayside. I didn’t prove how the water stays liquid overnight.” Is that so? Hmm. Is the need for a GHE reduced or increased? So how much GHE effect do we need with this model to keep most of the water between 1 and 6 deg C 24/365? Is it the same as the Toy? How much of the GHE is adiabatic and how much is back radiation as a function of GHG (which is mostly H2O)?
It’s not supposed to be a proof of anything, it’s most definitely not supposed to be a model of real world systems. You are not supposed to complain, when it’s not something, it’s not supposed to be.
It’s just a extremely simplified model that may or may not help people to understand, what GHE is. If it doesn’t help you, please ignore it totally.
In my case, the Toy model did not help. When I was reading Postma, I was thinking “that’s a ridculous strawman.” The hundreds of comments made clear it is a real, simple model that people were defending. I would not trust any “enlightenment” coming from the Toy.
The most simple model that should ever be taught is one that has night and day. A coin that flips every 12 hours. No, that concentrates energy, too much. How about an octahedron with a vertex pointed at the sun? Or the buckyball.
I don’t really understand your point. The toy model was not discussed much in the argumentation. There was some discussion, where Postma and his defenders tried to maintain that same position that you present here claiming that main stream supporters would give credit to the model. All the main stream supporters told that they really don’t and that the model’s unrealistic nature is always accepted and presented. This was just an perpetuated strawman argument by Postma and his defenders.
Everyone agrees that the model is not a valid model of any real planet (on that point Postma and all others agree). The only question, where opinions vary is, whether it’s in spite of that a useful educational example. It can explain one phenomenon, but it’s obvious that some people may take it erroneously as an approximate description of the real Earth GHE even, when they are told that it’s not that. Thus it has a good point and a bad point. Educators should use it with care, if they decide to use it.
Most of the discussion was on the other part of the Postma paper that claimed that the GHE is not important but that the temperature of the surface can be explained miraculously by the difference of day and night. Others pointed out that Postma did his calculations in reality as if the night would not be there at all. Of course he didn’t accept that, but that was really the point leading to an error by a factor of two. That was one of the two major errors, the other one was essentially imagining that sun warms as effectively everywhere as it does at equator (that amounts to an error of pi/2=1.57). Most of the discussion was trying to explain the errors in different ways.
Postma made his error in calculating average power densities. Thus much effort was used looking at the calculation of average power densities.
The other approach that I took for much of the discussion was looking at the total energy balance of the Earth surface, because it’s in some way more basic to look at the total energy fluxes than to look at the average densities of the energy fluxes. Of course the approaches are equivalent, but one may be easier to understand than the other. I preferred my approach, because it makes it easy to tell numbers for all main factors. The numbers were totally devastating for the Postma case. I asked him several times to present an explanation of that observation. First he just pretended not to notice my request although it was repeated in places, where he was participating in the discussion. Then I told that I consider the question a test of honesty. That made him answer, but of course not to the question itself, but something totally irrelevant for the question. How else could he have done, when he cannot have any valid answer to support a “theory” based of crude errors of factor 2 and factor pi/2. Nothing but mumble jumble can be presented by someone caught so terribly wrong, but not willing to admit that.
Then we have still the people, who declare that they cannot follow the discussion, but use their ignorance to maintain the position that all arguments are of equal value and that the argument is not decided. Some of them feel even free to formulate that opinion as insults on those, who have explained in detail and as clearly as they can, how terribly wrong the Postma paper is. Pathetic.
Mind you I believe the Earth does have a GHE;
This comment helps clear things up for me. If there is something else you are skeptical about, then we may not disagree. However, if you believe there is validity to Postma’s argument that the climate can be explained without the GHE, then that is still an untenable position. His argument can clearly be seen to have no merit, as has been exhaustively explained in the previous thread, independent of the simplified model under discussion.
I am skeptical of almost anything except the concept that “We do NOT live in a BINARY world.” It isn’t “Is” “Is Not”. It is how big and what is the range of uncertainty.
It is not whether a GreenHouse Effect exists, it is rather how powerful it is. By the way, what are the units that specify the strength or power of a GHE in any given configuration?
It is not whether CO2 contributes to the GHE, but what is quantitative difference in the GHE when CO2 concentration changes from 350 ppm to 400 ppm.
What drives me most crazy about climate science that I have seen so far is the tendency to express uncertainty as ” >75% probability that A is greater X”. I don’t think that way. My industry doesn’t think that way. We think the P90-P50-P10 of A is X90, X50, X10. Capture and communicate the range.
When it comes to quantifying the GHE, I would like more clarity on the different components of GHE. How much of it is adiabatic? How much of it is phase change of water (heat of fusion, heat of vaporization)? How much is back radiation by each gas and its concentration?
Do these questions meet your threshold of legitimacy?
The questions are certainly legitimate, and although 100% certainty is unachievable, they have been addressed in detail throughout the climatology/geophysics literature. GHE strength is typically expressed in terms of “climate sensitivity” (deg C rise in temperature per CO2 doubling), and these values have been assigned pdfs, with the ranges debated thoroughly (including a previous post here on the topic) – a typical 90% confidence interval encompasses the range between 2 and 4.5 C., with much discussion of reports citing values outside that range. The logarithmic relationship between CO2 concentration and W/m^2 forcing (with consequent effects on temperature that are linear within the restricted range under consideration) has been quantified and explained, with the delta flux equal to about 5.35 ln of the ratio of the changed CO2 to the previous concentration. The respective roles of the dry adiabat, moist adiabat, and convective adjustments to the adiabat have been estimated. The back radiation as a function of the concentration and radiative properties of CO2, water vapor, clouds, ozone, methane, and other constituents has been analyzed, and the flux measured at various sites, including wavelength-specific measurements that distinguish between different molecular sources. The negative lapse rate feedback due to latent heat release has been evaluated and compared with the positive feedback from the heat-trapping properties of the same quantities of water vapor, with the difference between them, which is positive, found to be less variable than either quantity alone..
Obviously, those questions can’t be answered in a few comments, but I think it is to Dr.Curry’s credit that one can go back through all the posts and threads and find much of this material even without the need to refer to cited papers or texts.
Rather than continue to be driven “crazy”, you should probably go back and visit this material here, and if you want more detail, read the textbooks and start following the literature as well as the blogosphere.
Fred, GHE is far more than sensitivity to CO2 concentration changes, isn’t it?
Let me back up to first principles: There are heat trapping mechanisms in the daily cycle of the earth’s heat flow. I have been lumping them all as GHE.
GHE certainly includs
1 — back radiation from GHGs, of which CO2 is only one and not the most important one. Agreed?
The following heat trapping mechanisms are also in play.
2 — Heat Capacity of water and air in the ocean and atmospher.
3 — Heat of Fusion as water turns to ice.
4 — Heat of Vaporization as water vapor condenses into water.
5 — Adiabatic physics of the atmosphere.
6 — Thermal conductivity of the air and water in the ocean.
I will not include convection here. all the above are valid in a model with changing temperatures and without currents.
Here I make an observation that I invite your comment:
The Toy model is a static, single temperature model, and as such the contribution of 2 through 6 are zero. The whole answer is in 1, the GHGs.
But in Postma’s model, which I find far more realistic than the Toy, Temperature MUST vary by lat, Long, h, t. Heat is trapped by all mechanism 1 through 6. and as a result, the contribution of the GHG to GHE might be smaller that implied by the toy model.
Here is my crucial set of questions:
Does GHE include A) 1, the back radiation? or B) all heat trapping mechanisms 1 through 6.
If A), what then do we call 2, 3, 4, 5, and 6?
If B), then what are the units or dimensions of GHE to capture its strength?
Stephen – We’re running into problems with column width. If you want to start a new comment, that would avoid the problem. You asked about units to measure GHE strength, and climate sensitivity addresses that.
Regarding some of your other points, GHGs are heat trapping molecules, but I wouldn’t call the other phenomena trapping mechanisms, although all are important for the rate and location of heat changes. Of the GHGs, I would list CO2 as the most important as a climate driver, with methane second, followed in no particular order by nitrous oxide, halocarbon compounds, tropospheric ozone, and a variety of others. With the exception of water derived from methane oxidation, water doesn’t belong on the list because its short atmospheric lifetime prevents it from having a role in determining temperatures except as a feedback mechanism.
I didn’t pay too much attention to the “toy model”, but because the GHE requires a lapse rate, the adiabatic element is important in any description of the GHE.
I don’t know whether I would characterize Postma’s description as a “model”, but I do know that it was wrong, because no matter how tweaked, it couldn’t account for the surface temperature of our planet. That was documented in adequate detail, I thought, in the previous thread, including a contribution I made, based on much of the earlier discussion, in which I dissected the various fluxes in ways that would allow anyone to compute them and refute the Postma conclusions. See Comment 101095.
I in your comment 101095, you were using a constant temperature argument, Yes? In a constant temperature model, only Back radiation is available to provide the needed warming or heat retention. But in a variable temperature day-night model, your have at least five other mechanisms (my 2 thru 6) that will also help retain heat. I think the variable temperature aspect with all the heat storage factors is crucial to to understanding the energy balance.
I will continue this line of thought in a first level comment with a summary and link back to here, but I’m out of time for the night. I’ll sleep on it.
Stephen – Constant only in the sense of averaging. Not constant either regionally or diurnally. If you take all individual temperatures at different locations and different times of day, computed the emission rates for each in W/m^2, added them up, and then computed a temperature that would yield the same emission rate (about 390 watts) averaged over every square meter of the surface, you would arrive at about 288 K, based on observed values. Postma agrees with this part of the exercise. There are probably a few ways this could be tweaked (as I suggested in the linked comment and you could try out examples), but they aren’t going to come out with anything even remotely close to what Postma’s attribution of surface temperature to solar influx alone would give us – that would make the planet an extremely frigid place to live.
(In fact, if you created an absurdly unrealistic scenario designed to maximize his argument, you could do the following. Consider the Earth as a flat disk rather than a sphere, with one side always facing the sun at right angles to the irradiance (no slanting), and then have it instantaneously switch sides every 12 hours (without any slanted intervals). Subtract the albedo (about 30 percent) and another fraction for solar radiation absorbed in the atmosphere (about 23 percent, with no downward emissions but allow some of this energy to be conducted to the surface from lower altitudes – e.g., 10 percent of the irradiance), Here, the average value is clearly one half of the total irradiance (not 1/4 as in a realistic scenario), and every illuminated region will receive the same irradiance.
When you do this, which in effect doubles the energy the Earth actually receives, the average emissions will turn out to be about 411 W/m^2, which is only slightly higher than the 390 based on the observational data, with only a minimally higher surface temperature. Thus, even doubling the Earth’s rate of energy supply barely allows one to reach an average temperature comparable to the one we enjoy. This illustrates the gap between a solar source alone without back radiation and what is needed to keep us comfortable.)
I like the coin-flip model. I discarded that as being too hot. But If I can’t show enough heat retention in that model, I’ll conceed the issue. The test is whether the energy received in the daylight can be stored in non-temp radiating means (2,4,maybe 5), and bleed back at night to keep H2O liquid. Later.
So since you do not dispute the existence of the greenhouse effect, and ask a legitimate question about it’s strength, here is a quick answer. Currently the GHE is about 155 w/m2, but it varies with latitude ranging from about 250 w/m2 in the tropics to around 100 w/m2 at the poles, mostly because of changes in water vapor.
So the 64 dollar question is how will this change with increases in anthropogenic CO2? Just the increase in CO2 will strengthen it some, but the feedback uncertainties are large. It is almost certain that it will increase with increasing CO2. Is is also 100% certain that it will stay at an elevated level for thousands of years, which is scale at which geologic removal of CO2 from the biogeochemical works. The canonical estimate of the value of S (sensitivity for 2X CO2) which is 2C to 4.5C provides a range of values. There has been a steady trickle of papers which dispute this on the low side, but none seem to have gained traction.
Rattus, thank you very much for the reply. Thank you for the Range in GHE values and confirming that water vapor is a large component of the range. Do you have a link to the source of these numbers so that I can follow up?
I noticed you use W/m2 for GHE strength, which makes sense, but then shifted to deg C per doubling for CO2. Ever seen the CO2 part expressed in W/m2?
Excuse my absence from the discussion these past 3 days. I haven’t given up the subject, just pre-occupied with end-of-summer driving from Colorado to Houston. I thought much about this thread while looking at towering thunderstorms in the rear-view mirror in CO and observing whether or not I could see UHI effects passing through northern Texas towns at 104-110 deg F. But those thoughts will be left for a level 1 post, not here.
Peka,
You and I know what you say is false. Postma (and the Slayers) cited 60 examples where universities from Standford to MIT are teaching students the zero-D model and no other. The Slayers have hunted high and low for a more complex model but none exists in academia. If it doesn’t exist in academia where is it? Last year I asked Judith Curry to provide me with a more complex model that is taught at Georgia Tech than the K&T zero-D version and she couldn’t offer me one.
John, read my post, including the wikipedia link i provided and the discussion of radiative transfer models. I have dozens of models that are used for different applications, that are used for teaching and research at Georgia Tech. There is just no point in going further until you accept the basic physics behind infrared radiative transfer.
If you want a complicated model, here is one example, you can download the code and read all of the the documentation. Once you’ve done that, then lets talk.
http://www.cesm.ucar.edu/
Dear Curry,
the models you have linked to have all FAILED to predict the current temperature trends and yet you continue to insist that these models provide validity for the so called “greenhouse effect” hypothesis.
That is an untenable position.
These models have failed to predict the current reality because they are based on a failed hypothesis, false assumptions, and incorrect input parameters.
One specific and easily identifiable example of this is “convective parameterisation”. It is simply impossible to correctly estimate the total convection taking place on a planetary scale. If you overestimate convection you get cooler estimated temperatures than the observed.
If you underestimate it, your model produces exactly what occurs inside a greenhouse.
GI=GO.
Shouldn’t it be: (GI+GO)=0
Pekka, if you had read Postma’s paper with any care you’d have seen 60 cited examples of universities teaching the zero-D model and no other. I asked Dr Curry to advise me if Georgia Tech teaches only from the zero-D model.I have never received an answer.
John, I replied to you at length already on the blog, including the links to sokolik’s text that a number of people have commented on. This describes what Georgia Tech students learn about radiative transfer.
[this is a rewrite of my third paragraph above]
A relatively simple model of a rotating “buckyball” with a day and a night might be a more reasonable simple model of energy balance. I think you have only 5 unique surface orientations, convolved with 4 basic surface (jungle, desert, water, snow/ice), rotated in (12, 18, 24..) discrete time periods of the day on an axis through opposite vertexes. It is certainly more complicated than the zero-d model, but this is easily done in one small Excel worksheet as a homework assignment.
When creating a mental model of the GHE there has always been two approaches, two points of view, looking up and looking down.
Most here will be familiar with the looking up POV, the one with DLWR and many will not like it.
The alternative perspective, the looking down POV, has at least as long a history and I know it was once taught at the graduate level.
The alternative, looking down model explains exactly the same GHE, only the POV is changed.
A model that explains the 33C discepancy by way of the lapse rate and a significant height (~5km) but fails to mention how this height is determined is just the GHE in another guise. It is the downward POV of the GHE but without mentioning the GHGs on which it relies.
There is nothing novel in an explanation based on a lapse rate mechanism, it is well trodden ground, and it relies on just the same GHE. Only the POV has been changed.
Anyone who has rejected the upward POV (DLWR and all that) and accepted the lapse rate mechanism as an explanation, on the basis that it makes the GHE go away, has been sold a pup, and should ask for their money back.
Alex
Western academics must stop tilting at windmills. Does anyone believe Western civilization should continue to put promoters of wacky-science on the public dole?
“Hence, the big question: if in the Middle Holocene, when dung and firewood were the only fuels used by Mankind and the world population was at least two orders of magnitude smaller than today’s, there were temperatures and sea levels considerably higher than the present ones; if the atmospheric warming at the end of the Younger Dryas 11,600 years ago and the sea level rise between 18,000 and 6,000 years ago were much faster than the observed since the 19th century; so, where are the evidences that would allow us to point to the “human fingerprint” in the small variations of the latest 140 years, against the background of the much wider and faster natural oscillations of the historical and geological past?
“The answer is: there aren’t any (for evidences I mean, obviously, hard facts observed in the physical world, not mathematical concoctions extracted from the climate models).”
~Geraldo Luís Lino
Judith,
I like your chapter…though, Equation 14.13 does not appear correct,
it should be To = [(n+1)^1/4]Te*
Yes you are correct, i copied the text from my word version of the chapter, that is in the errata (which i forgot to check). thx for pointing this out.
Dr Curry writes “If you want to disprove the existence of the greenhouse effect, you need some sort of alternative explanation for a whole lot of fundamental physics that explains the infrared emission spectra as measured at the Earth’s surface and high above the emitting portion of the atmosphere (see Pierrehumbert). ”
I am not interested in disproving the greenhouse effect. The majority of skeptics agree that AGW is real. The problem we have is with catastrophic AGW (CAGW).
It is impossible to prove that the hypothesis of CAGW exists. I write “impossible”; I mean “impossible”. There is no science, no physics, no observed data that shows that CAGW happens. Such little observed data as we have, tends to show that climate sensitivity is significantly less than 1 C for a doubling of CO2. How much less, no-one has any idea. The effect could be completely negligible. There is simply too much noise in the data on GMTs. Noise, by definition, averages it’s signal to zero if there is enough time to do the integration. However, we have very little data on what constitutes natural noise; what it’s amplitude is, and what it’s time constant is. There are indications that some significant noise could have a time constant measured in centuries. In which case, it is simply impractical to ever have a long enough data base for this noise to get averaged to zero.
So I suggest, Dr. Curry, you forget about trying to convince skeptics to stop trying to prove that CAGW is scientific nonsense.
I suppose it is impossible to prove a concept with no scientific definition…
Chris,
That is an annoying bit of ignorance on your part.
Of course CAGW has a scientific definition. Hansen, et al have been selling just that for over 20 years.
To dodge that makes you look cowardly.
Mr. Chris Colose, Please let Mr. Ben Bernanke (our current money scientist from Princetown), know this fact before he discovers that ‘gold IS money’.
PS Please hurry. Thank you.
Really?
How do you quantify that? I read some “skeptics” say that is so – but when I look at these here threads and those over at WUWT, I see many a post from “skeptics” who doubt, even, the GHE. I see, over and over, statements that the GHE was an “invention” for the purpose of justifying political goals.
Perhaps you’re right. What’s your evidence?
Indeed Joshua, there are some skeptics who think AGW is real (that is, significant) but benign, but they are a relatively small minority. Pat Michaels for example, who argues that future AGW will be like the past, less than a degree on winter nights, etc. Perhaps the so-called lukewarmers fall into this camp, I really don’t know that much about them.
But the vast majority of skeptics are skeptical of AGW for one reason or another. Of those there are two camps, those who think the jury is still out and those who are convinced that AGW is either insignificant, false or phony. Note that as the latter camp falls into three sub-camps we have a taxonomy going. One could also subdivide the population according to the reasons they give.
David –
I guess my interest is in breaking down that last group and getting a sense of the relative size of the sub-categories. Jim above, and often Judith, say that the “false or phony” group is relatively insignificant in size; my sense is that it isn’t. I often see the size of the “jury still out” group downplayed. And I think that depending on the particular thread or context, some folks move back and forth between groups. And hunter says that the dragon-slayer contingent is a majority or skeptics, although looking at the threads, that doesn’t seem to hold up.
At any rate, I think that some “skeptics” are too quick to diminish the size of those sub-groups, and I’m “skeptical” about their reasons for doing so.
Joshua, false or phony is two different groups, and each is substantial. So are the lukewarmers. Dragon slayers are too new but gaining ground. It is an empirical question how big each is and the polls do not properly discriminate them. Moreover, as you point out below, a skeptic may participate in different groups, depending on the argument at hand.
Lukewarmer is easy.
1. we accept radiative physics. GHGs warm the planet, they do not cool it.
2. We accept the range of sensitivity cited by the IPCC.
3. If you give us an over under bet on sensitivity at 3C, we take the under
4. Free the code, free the data, open the debate.
Or rather there is a debate in climate science, but you dont get to join that debate until you accept #1. You can debate #1 if you like, but dont be shocked when Ray P doesnt show up to waste his time. (no disrespect to the guys who do show up to attempt a discussion)
Mosh, what you describe sounds like accepting AGW but not CAGW, which sounds right to me. However if you agree with the assessment that AGW becomes dangerous at 2 degrees then your lukewarmer might accept DAGW (dangerous but not catastrophic). Of course every group of skeptics has a full range of shades therein. Given the range and complexity of the arguments there are few if any sharp divisions here.
“1. we accept radiative physics. GHGs warm the planet, they do not cool it.”
Radiation is a cooling process, not a warming process.
An object or substance, is heated by the energy it receives and cooled by the energy it looses, RADIATES.
Perhaps this confusion is the source of your relentless ignorance.
GHGs slow the rate of cooing. There is a lot of scope for that effect to be much slower than the IPCC believes will happen. Ultimately the warming will probably win though. I wouldn’t rule out “ultimately” to be measured in millennia.
Any substance in between a body (such as the Earth) with a temperature and space with 0K temperature (empty space) slows down cooling of the body (the Earth). If there are multiple substances (such as air) in between, then those have less radiation effects (such as N2 and O2), will have less effect of cooling the body. Those have more effective radiation effects (such as H2O and CO2) will help those less effective substances (N2 and O2) cooling faster due to moleculer collisions in the exchange of energy.
I’d like to add to that Mosh, lthough it may not be one of your personal points…
5. We dont believe that today’s temperatures are necessarily optimal for life on earth and dont discount the fact that that higher temperatures may be on the whole beneficial.
Joshua, Please slash the A in AGW… ok? Time will tell the rest.
Strong men believe in cause & effect.
R.W.E.
See a simple agenda, laid out…
http://www.un.org/esa/dsd/agenda21/
Hope, it helps.
Now that, to me, seems like a more accurate way to go. I see reason to believe that yes, many “skeptics” accept GW but not AGW.
But even there, I find claims about disproportionality to likely be overstated.
I read people say “Most skeptics don’t deny that the climate is changing, we just don’t think that the change is anthropogenic,” right before they talk about how much snowpack there was this year in the High Sierras, or how some seals uncharacteristically showed up in Boston Harbor, or how the measurements that show warming were corrupted by the UHI or deliberately manipulated by fraudulent scientists bent on creating a socialist “One World Government.”
In other words, I read people saying that they don’t doubt GW and then turn around and present arguments that suggest that they doubt GW. It happens quite a bit. I don’t know how to quantify the proportionality – but from what I’ve seen, many folks want to portray the proportions in ways that don’t fit the evidence.
http://www.drroyspencer.com/wp-content/uploads/AMSRE_SST_2002_thru_July_31_20112.gif
We don’t doubt present GW, or that the climate has always changed, but we do doubt that it has been quantified as accurately as is claimed.
Making points about levels of snowpack are a form of weather-is-climate argument, and not valid whether used for or against. I only use them as counter to the pro-AGW weather-is-climate stories, but I suppose some people may have genuinely got the impression that weather is climate. The mainstream has certainly worked hard to give that impression.
What do you mean “we,” Kemo Sabe?
How many times have we read on this blog about “global cooling?”
In fact, Tallbloke showed up right on cue.
In fact, the plot shows a strong global averageness.
Joshua, you are once again, making remarkable progress… Now that we agree man has nothing to do with the weather let’s move on to Agenda 21.
Here is an agreed to plan that is well laid out for all to read. Turn left and you are here. Nuts…
You noticed that too.
You will find that very few skeptics have a well thought through position about what they believe. If you even try to get to a common ground about whether it is warming or not, some will resist. Until you question the existence of the LIA. Then, they will believe in warming and thermometers.
Tactically they dont need a consistent world view. But I cant live that way
It’s warming AND cooling, depending on timescale, magnitude and significance.
Regarding thermometers, it’s really not that complicated. One can believe that the trend at the particular time scale is warming for example, but one can still disagree on the magnitude of that warming.
Mr. Steven Mosher,
“You will find that very few skeptics have a well thought through position about what they believe. If you even try to get to a common ground about whether it is warming or not, some will resist… Tactically they dont need a consistent world view. But I cant live that way”—
Yes we will & it should scare the hell out of us. Lots of U.S. regular folks, believe in this End Mode…II Peter 3:9-13. And yes, man does have ‘something’ to do with it all. Have you read the seventy books of the Bible, & do you believe in the plan of God? Perhaps, there is a ‘stumbling block’ in the way of science? I know the Bible, is not peer reviewed but it has been very accurate over six-thousand years (or six days; please read II Peter 3:8). Please,…Do not resist:)
people should be skeptical of CAGW; skepticism about the existence of the greenhouse effect is not defensible, this is what i am trying to convince people of. The existence of the greenhouse effect is not equivalent to CAGW.
i.e. the degree of its effect – from helpful to insignificant to carbongeddon, no?
Judy, you do not answer my question about the greenhouse effect you are speaking about: Is it based on a simple radiation model without thermodynamics?
The discussion is about CAGW, or a potentially catastrophical greenhouse effect. If you agree that the greenhouse effect,
whatever it is, is so small that it cannot be observed, then there is little to discuss. Is this what you are saying? That there is a greenhouse effect but that it is so small that we can forget it? If so, tell your readers and much time and effort will be saved. If not, you seem to believe in CAGW which you say one should be skeptical of.
Your readers expect you to speak out.
yes, I am referring to the so called tyndall gas effect, the infrared radiative transfer. The response of the atmosphere to the heating is both thermodynamic and dynamic. Lets settle on the radiative transfer part first. We have had these discussions on the earlier greenhouse threads. the word greenhouse is bad terminology.
Judith, please can you help me understand something. Do proponents of AGW believe that the ‘back radiation’ is ‘additional energy’ when it hits the surface? Surely the surface cooled by the amount of longwave it emitted before it ‘re-warmed’ when the ‘back radiation’ bounced down again.
I can see that sunlight absorbed in the atmosphere and propogated forward to the surface as longwave is ‘additional energy hitting the surface’ (not that it does much IMO). Surely scientific people differentiate between these components?
the earth received radiant energy from infrared emission by gases such as CO2 and H2O and also clouds. The earth’s surface temperature is determined by a balance of fluxes for shortwave and longwave radiation, sensible and latent heat fluxes, freezing or melting of water, and thermal conduction in the ground or mixing of the upper ocean.
Well, yes, but with respect, I can’t tell from your reply whether scientists differentiate between ‘new’ longwave and ‘recycled’ longwave. I can see that if fluxes are properly considered that should cover it, but a lot of scientists seem to talk about ‘Downwelling longwave’ as if it can be considered as an energy flow in its own right, without regard to the fact that most of it was previously emitted by the surface thereby cooling it, before ~30% of it returned to haunt us.
There’s a lot of double accounting going on.
There is an upwelling and a downwelling flux. Upwelling-downwelling = net IR flux. You also need to account for evaporation (surface loss) and sensible heating (usually surface loss, not always). Why is this so difficult?
Hi Chris, as I see it, there’s only one flux, and it doesn’t just contain radiant photons going up or down, but sideways, at 45 degrees etc etc.
My point is that we can understand more about the degree to which the flux is slowing the cooling of the ocean if we differentiate between the quantities of radiation which are contributing to new effects, and the quantities which were already emitted before they were re-absorbed.
tallbloke, Chris is right. These two fluxes can be treated independently. It is wrong to think of it like reflection. They are separate emissions in each direction.
Jim, where did I mention reflection? Back radiation was emitted by the ocean which consequently cooled before it came back down to the surface along with ‘new’ longwave derived from theabsorption of solar radiation in the atmosphere. True or false?
“back” radiation exists because the atmosphere is warm. Whether it is warm due to radiation or convection is beside the point, but actually it is convection that keeps the atmosphere warm.
Jim D,
“… actually it is convection that keeps the atmosphere warm.”
Congratulations you have evolved from the CO2 ivory tower.
Convection keeps the atmosphere warm, when the back radiation from the atmosphere keeps the surface warm to feed energy for convection. These go together. Without the convection the surface would be even more warm and so would the lowest levels of the atmosphere, but the higher altitudes would be colder.
LOL, I love this! With 2/3 of the radiation to the surface from the atmosphere, then the back radiation could very well be considered the up welling. It is like who have more angels on their pin. What I think is lost is that nearly 20% of the atmospheric warming is caused by direct absorption of solar which is “new” energy warming the surface, the rest is just hot potato energy being passed back and forth which reduces the rate of cooling.
SamNC, most heat enters the atmosphere via the surface. Why should that be controversial? AGW needs this fact to explain the tropospheric lapse rate, which is a critical part of the argument in climate sensitivity.
Jim D | August 20, 2011 at 11:40 am
Jim, not sure if that reply was to me, but if so, it doesn’t answer the question I asked, which was:
“Back radiation was emitted by the ocean which consequently cooled before it came back down to the surface along with ‘new’ longwave derived from theabsorption of solar radiation in the atmosphere. True or false?”
Looks like Dallas gets it anyway.
Pekka Pirilä | August 20, 2011 at 12:00 pm |
“Convection keeps the atmosphere warm, when the back radiation from the atmosphere keeps the surface warm to feed energy for convection. These go together. Without the convection the surface would be even more warm and so would the lowest levels of the atmosphere, but the higher altitudes would be colder.”
How the back radiation feed energy for convection? You keep yourself confused with convection from the ground surface and convection from air to air. Only the warmer air below keeps convection goes on with cold air above. Energy is fed from air below at warmer temperature. Not from the same temperature at the same altitude level’s back radiation.
Jim D,
I found your lapse rate confusing, how do you define lapse rate here?
Jim D | August 20, 2011 at 12:20 pm |
“SamNC, most heat enters the atmosphere via the surface. Why should that be controversial?”
No controversial at all as heat is convected and conducted to the atmosphere from the Earth’s surfaces. Controversial is that the Earth surface LW radiation heat does not heat up the atmosphere at all but AGW believers insisted that the radiation part do most of the heat transfer from the Earth surfaces to the atmosphere.
” AGW needs this fact to explain the tropospheric lapse rate, which is a critical part of the argument in climate sensitivity.”
Define your lapse rate here and how to effect the backradiation heat up air.
tallbloke, yes, my 11:40 pm answer was to you. “back” radiation does not require upward radiation to be doing much. It only requires a warm atmosphere, and convection is mostly what keeps the atmosphere warm. So I can only give your true or false a ‘partially true’. As I say elsewhere, the net effect of IR is to cool the atmosphere, which helps convection.
SamNC, no IR radiation is not a major source of heat to the atmosphere when you consider that its net effect is cooling. The tropospheric lapse rate comes from convection and the properties of water condensation in it. So the air temperature is mostly determined by the lapse rate, and IR radiation from the atmosphere is determined by its temperature and GHG distribution.
Jim D | August 20, 2011 at 1:23 pm |
“SamNC, no IR radiation is not a major source of heat to the atmosphere when you consider that its net effect is cooling.”
There is no dispute here that IR is cooling as air IR energy is radiated towards the space.
” The tropospheric lapse rate comes from convection and the properties of water condensation in it.”
Water condensation in the atmosphere is due to loss of its latent heat to the space via radiation or thru convection to nearby colder air. I have no problem with that.
” So the air temperature is mostly determined by the lapse rate,”
So your lapse rate is defined as the loss of heat content in the air due to convection to lower temperature air nearby and and IR radiation to the space. I have no problem with that.
“and IR radiation from the atmosphere is determined by its temperature and GHG distribution.” I have no problem with the 1st part, i.e. ‘IR radiation from the atmosphere is determined by its temperature’, but how do you get the GHG distribution into the picture. GHG distribution is only a small composition of the air. Its lapse rate is minimal, heat content is minimal.
SamNC, you and others, like Arfur Bryant who just posted, always say it is only 2.54% so how can it do anything? It can, and you can work out W/m2 of radiative fluxes from them, and they are significant and they are measured to be the expected values at the expected wavelengths. What else can be needed to convince someone? Even if you have no hope of understanding the theory, you should understand the measurements.
Jim D | August 20, 2011 at 1:56 pm |
“SamNC, you and others, like Arfur Bryant who just posted, always say it is only 2.54% so how can it do anything?”
No, wrong with CO2, it has only maximum of 0.04% of radiation absorption effect when all CO2 in the atmosphere assumed to have 100% effect of intercepting of the Earth’s IR radiation. 390ppm effectively in empty space can maximim absorb 390/1,000,000 th of CO2 absorption wave bands if the CO2 has 100% absorption efficiency. I have been extremely generous to give credit to CO2’s absorption of IR radiation from the Earth’s surface IR radiation.
” It can, and you can work out W/m2 of radiative fluxes from them, and they are significant and they are measured to be the expected values at the expected wavelengths.” Show me your calculations.
“What else can be needed to convince someone? Even if you have no hope of understanding the theory,.” When you are facing the reality of the thermodynamics and radiation laws, you always resort to these negative comments that will not help you to understand energy contents of air and CO2.
” … you should understand the measurements” I have done measurements and calibration to standards for years. Do you understand measurements?
There is no hope for you to understand that GHE is violating radaition and thermodynamics that you prefer to stay inside the CO2 ivory tower.
SamNC, I don’t think Arfur was wrong when he said 2.54% because he was including H2O which is also a GHG. You can take it up with him. You say you know measurements, so when you have a measurement of 300 W/m2 downward IR from clear sky, how do you interpret that? Science has its explanation down to the specral details, but maybe you have an alternative. Can you explain why the spectra correspond to CO2 and H2O lines?
Jim D | August 20, 2011 at 3:09 pm |
“SamNC, I don’t think Arfur was wrong when he said 2.54% because he was including H2O which is also a GHG. You can take it up with him. You say you know measurements, so when you have a measurement of 300 W/m2 downward IR from clear sky, how do you interpret that?”
I don’t do IR measurements but I can tell you that 300W/m2 if measured is the air’s total radiation measurement at its temperature of radiation at the point of measurement which has almost nothing to do with GHGs which CO2 is only a trace gas contributed minimal quatity of IR heat content. Major radiation of heat comes from the air. Even though the sky is clear, the measurements contain refractions which has energy contents greater than CO2’s and if the moon is above, reflection from the moon is greater than CO2’s radiation and if you include the terrestrial stars radiations, they are most probably greater than CO2’s radiation contents.
” Science has its explanation down to the specral details, but maybe you have an alternative. Can you explain why the spectra correspond to CO2 and H2O lines?”
Science is limited so far on radiation measurements of O2 and N2, especially N2. You can do an experiment by heating N2 in a glass container to say 100C to see if the N2 in the glass container radiates energy and measure the cooling rate inside. You can also do that with pure CO2 gas in an identical glass container and do the same measurements. You can also do the same with air in glass container and measure the cooling rate of the air inside the glass. You can compared with the results and see if the N2 can cool by its radiation. You can also place ice inside a glass container near the N2 glass container and another ice in another galss container which is completely blocked radiation from the N2 container to verify if N2 raidates IR waves. These tests should be done in a laboratory with controlled environment.
SamNC, your hard-thought theory, which I am sure you prize as a major academic achievement falls down when you try to explain (or ignore in this case) the spectral lines in that IR radiation. Especially if you see an emission peak at 15 microns. How does your theory explain that one? A long-lost O2 line?
Jim D,
“A long-lost O2 line?”
There are plenty of O2 lines, which one you like?
~700nm and ~1300nm.
SamNC, you probably did not notice that your wavelengths are not in the part of the IR that matters for temperature, and those O2 lines would be several orders weaker than the CO2 lines.
Jim D,
No, I said CO2’s 15um is not significant compared with whole spectrum of IR radiation. CO2 dwarf miserably compared with H2O in the air and H2O dwarf miserably compared with the Earth’s surface radiation. Heat content is proportional to their compositions with their respective specific heats.
N2 radiation spectral content cannot be determined by the present technology does not mean it cannot radiate IR wavelengths. Its just the science is not capable of measuring them at the moment. You can do the experiments to determine if N2 has the IR radiation effect as suggested by me a few threads above.
Jim D,
O2 has shorter wavelengths bands. In general, shorter wavelengths means higher energy intensity as compared with CO2’s 15um. O2 has 3 orders of magnitude more than CO2. Its interception of the Earth’s IR radiation will dwarf CO2’s interception of 15um.
3.7wm-2 forcing per doubling isn’t it for CO2? Hardly insignificant.
I think we can safely assume scientists have measured the radiative properties of N2 and found it lacking.
SamNC, if you were able to find a spectrum of downwelling longwave radiation, particularly in dry environments you would not say 15 microns is insignificant. It would be a dominant feature. Even more so from a satellite looking down anywhere on earth.
Jim D,
Are you sure satellite radiation measurements indicated all or mostly 15um? If not what is the proportion of radiation energy (or heat flux or whatever you call it) at 15um, other wavelengths. I thought spectral lines present to identify atoms of different materials. Can you confirm with NASA that their radiation measuring equipment not biased with a band of particular wavelengths? Or is the instrument just measured total radiation that are detectable to their instrument design and unbiased/neglect others? Has the calibration done against all wavelengths all intensities?
SamNC, the instruments measure all IR wavelengths equally well, and the 15 micron band would be a prominent dip from a satellite due to emission by CO2 at high levels. I could answer the fraction of the amount by using MODTRAN, but I won’t.
Jim D,
Judging from your upset about my comments on the MODTRAN, my apologies if your family living depends on your MODTRAN.
SamNC, not upset. I think you are quite comical, and not at all serious.
Jim D,
Not that MODTRAN again! Any climate models are manipulted to give the modeler desired results. You are correct, I have zero faith in them.
Yes, I know radiative transfer is not your area of knowledge as you keep proving. It is therefore a waste of time arguing about the radiative models with you because those are the tools of the trade.
Jim D.
HaHaHa. You did it again. I told you your negative comments get you nowhere except inside the CO2 ivory tower. You cannot escape from it. Thats your life.
Ok Judy, so greenhouse effect is bad terminology and back radiation as well, and one should be skeptical to CAGW. How much then remains of the climate alarmism you seem to be defending? Or have you converted
to skepticism to alarmism?
I am skeptical in the true scientific sense. Read my previous posts on uncertainty, also attribution. I am not skeptical about the tyndall gas effect or our ability to simulate clear sky radiative transfer in the the atmosphere to within our capabilities of measuring basic atmospheric state and spectral radiances.
You said yesterday that satellites can measure the amount of longwave being emitted from the actual ocean surface. how do the satellite instrument people know how much of what they are measuring is coming from the contiguous surface of the ocean, and how much is coming from water vapour immediately above the ocean surface?
Read the validation reports. As I have explained many times to reconstruct the surface temperature from the sensor data, they apply RTE. All you have to do is visit any one of the data product pages and walk through the software descriptions. They lay out every step and radiation codes they use.
heres one. The ground truth comes from Buoys.
http://www.star.nesdis.noaa.gov/sod/mecb/goes_validation/test/background.php
http://www.star.nesdis.noaa.gov/sod/mecb/goes_validation/test/sst_validation.php
http://www.star.nesdis.noaa.gov/sod/mecb/goes_validation/test/val_coast.php
Hi Mosh. OK, they can validate temperature retrievals with buoys. How do they validate longwave emission? In situ measurements have the same problem.
What do you mean by “validate” long wave emission?
You have a sensor(s) that receives in various bands, some of then tuned to IR or tuned to say C02 bands ( transmission windows)
Are you talking about the calibration? That’s done on the ground.
Or are you talking about experiments where you have a source of known illumination and you do a retrieval of that? Like an IR beacon on the ground? Did that ages ago for star wars using a ground laser that operated in the correct band. This engineering CANNOT WORK if the dragon Slayers are correct.
http://www.aero.org/publications/crosslink/summer2000/03.html
or are you talking about sub orbital validation
http://www.google.com/url?sa=t&source=web&cd=7&ved=0CE4QFjAG&url=http%3A%2F%2Fairbornescience.nasa.gov%2Fsites%2Fdefault%2Ffiles%2Fdocuments%2FSPP_Rqrmnts_v6.pdf&ei=XVpPToivO6niiALrptiRAQ&usg=AFQjCNGEt26Fexf0u6yXbf2sNucPvuF8uA&sig2=2TwTh_ccXgEyihcHNFZ9hA
IR or any other band its the same problem. The physics of radiation transfer refers to the ENTIRE spectrum. I shine Xband at a target. I know my output. I measure the signal at the reciever. I can predict how that radiation will travel through the atmosphere. how different molecules will react. I can predict how that wave will hit an aircraft. How much will reach the aircraft, how much will be backscattered, absorbed, forward scattered, hit a millimeter crack and bounce back. Hit a rotating fan in an engine duct, scatter in the duct and come back out. the theory is well known and tested. I can do the same thing with IR. whether its the earth emitting IR or a jet aircraft flying at 600 KEAS. That sucker emits a tell tale signature in multiple bands ( hot gases, hot metal, aeroheating) and we know how that radiation propgates. Thats how we build missiles to shoot stuff down. And we know how bright to make a flare to fool that missile or how to build a device that sends out IR to blind the missile. I build a cell tower. I emit radiation. How far does that signal go? Depends upon the atmosphere and the radiated power. The atmosphere attentuates the signal.
These physics work. Because they work you won’t find engineers who have worked in this area ( like jeffId for example) who will deny RTE. why? cause we liked getting paid and we liked building shit that worked.
Mosh, all very cool, but I still don’t see an answer to my question:
“how do the satellite instrument people know how much of what they are measuring is coming from the contiguous surface of the ocean, and how much is coming from water vapour immediately above the ocean surface”
Also, light scattering in clouds is a bit of a problem area in theory. An experiment was done with planes carrying measuring gear above and below clouds simultaneosly. They used a stack of five planes I believe. The empirical result showed that the clouds absorbed 30W/m^2 more solar energy than theory predicted. This leaves a bit of a hole in the theoretical energy budget. The models are given ad hoc adjustments to try to deal with this, or so a modeler says.
Strong focussed signals are one thing. Measuring power associated with diffuse weak signals is another. An IR thermometer will tell you that radiation coming from the Sun is at ~5000k whether you are stood on the moon or pluto. The amount of power arriving is very different. Signal does not equal power.
Cheers
Dear Curry,
The confusion surrounding the “Tydall gas effect” as you call it, is the direct result of John Tyndall’s inability to distinguish between absorption, scattering and reflection, all of which are forms of absorption and re-emission.
At the time of his experiments, which are written up in his memoirs “Contributions to Molecular Physics in the domain of Radiant Heat”, Tyndall was completely ignorant of the fact that absorption does not equate to warming.
This level of understanding comes from quantum physics which was developed long after Tyndall’s demise.
In-fact in none of his experiments, does Tyndall ever attempt to measure an increase in the temperature of the gas under observation. He merely detected a decrease in the energy arriving at the pile, from the source and made the assumption that this would result in warming, but Tyndall was wrong.
Reflection and scattering are forms of absorption and re-emission. They do not have to result in warming. The potential for warming is determined entirely by thermodynamics processes which are governed by the 1st, 2nd, and 3rd laws. All three of which, “AGW” hypothesis and the “greenhouse effect” hypothesis are undeniably in complete violation of.
Judith – I hope that you’re congnizant of the degree to which “skeptics” are not aligned with the position you just stated. You seem intent on downplaying the # of skeptics who reject that basics of the GHE that you consider to be established fact. Read back over this thread, and perhaps you’ll reconsider?
Judith, you say ‘skepticism about the existence of the greenhouse effect is not defensible.’ But it is when discussing it in the form presented by the standard model. Postma has demonstrated that by the addition of calculations for night and day insolation, adding adiabatic physics and by scrupulously not mixing averages from the linear and non linear aspects of the equations the sum of the energy budget is the same WITH or WITHOUT a GHE. Thus:
Predicted earth emission without a greenhouse effect: 239 W/m²
Actual earth emission WITH a (supposed) greenhouse effect: 239 W/m²
Jim,
How do you define CAGW? Are you saying that 3 or 4 degs of warming would be catastrophic?
“Since I am no longer affiliated with any organization nor receiving any funding, I can speak quite frankly….As a scientist I remain skeptical…The main basis of the claim that man’s release of greenhouse gases is the cause of the warming is based almost entirely upon climate models. We all know the frailty of models concerning the air-surface system.”
~Dr. Joanne Simpson
Another one that isn’t a member of Jim Cripwell’s “majority,” eh?
Judy, you write a post
” to untangle the Skydragons’ misunderstanding about the greenhouse effect and the planetary energy balance”
and when I ask you a question directly related to my “misunderstanding about the greenhouse effect”‘, then you refuse to answer.
Is this how a serious scientific debate is to be performed? Why are you not answering my question? It is a serious question about the basics of climate alarmism and I expect a serious answer. If you are nor willing to answer you should stop criticizing my work in public.
Claes,
Sorry, but you have now earned the right to be ignored. We have had a whole thread (and overlap with several others) devoted to your nonsense, which hardly qualifies as a ¨scientific debate.¨ You have proceeded to distort Judith Curry´s word on your own blog. Sorry.
Chris, I have been advised that you were a student of Dr. Curry’s. Is this correct and does it color your comments towards Claes?
It is not correct. Also, I have disagreed with Judith Curry on numerous occasions but she is absolutely correct on this issue.
Dr Curry has recently conceded that back radiation doesnt exist in any thermodynamics textbooks,nor in the laws of physics. It is merely a hypothetical construct of the IPCC and she has affirmed she will no longer use the term. I’m pleased she’s slowly learning. When are you going to renounce such myths?
Wrong, i stated that the term back radiation is misleading terminology, because many people (like you) seem to misunderstand it. infrared radiation emission by molecules such as CO2 and H2O definitely exists. THe IPCC is correct in this regard.
The entire ridiculous and unsubstantiated 200 year old nonsense concept of the so called “greenhouse effect” is entirely based on thoroughly misleading terminology.
More commonly referred to as sophistry, fallacious arguments with the intent to deceive.
Judith, I disagree. It’s people like you who extol the work of Tyndall who are so off base. Tyndall was completely ignorant of the fact that absorption does not equate to warming. The American Meteorological Society refuted Tyndall’s ideas when they published their debunk of the GHE in 1951. Radiation is not the same as heat. Don’t you know these things?
John – Hopefully, we are all students of Dr. Curry’s.
Fred, so that’s your wish to see the blind following the blind?
Even if this were the case (and as Chris points out, it isn’t) it couldn’t possibly eclipse your blind defense of Dr. Johnson. Your ridiculous insinuation just points out, yet again, how little you people understand about how real scientists conduct themselves. Scientists argue – often, and strenuously. Yet they generally engage on a level playing field and discuss the issues using a common language and relying upon an implicitly agreed-upon starting point; they don’t just blather on about their new theory that nobody else is smart enough to comprehend.
Disagreement, and the desire to prove the other person wrong, is how science progresses. Almost every single published paper contains some flaw, but the overall progression is always towards the correct answer and often pays societal dividends along the way. Goodness knows there are roadblocks, and egos intrude – oh yes, they surely do. But there are no Galileos anymore, nor are there Dragon Slayers. But good luck with that.
I admire Dr. Johnson because he’s thinking deeply and trying to understand and clarify our understanding of radiative physics…taking a fresh approach and revisiting our assumptions rather than regurgitating formulas memorized from a textbook. Every formula is an approximation and a tool for describing an underlying reality. The formula is not the reality. Don’t believe what you are told…examine the data and assumptions and think things through.
I’m sorry Ken, but anyone who says that the equation P = sigma(To^4 – T1^4) represents something different that P = sigmaTo^4 – sigmaT1^4 is talking bullocks and is not thinking clearly.
Rattus,
It is you who is not thinking clearly. The P/4 argument postulated by Postma is entirely valid because it demonstrates that the standard GHE model, which omits the existence of night and day is utterly flawed. Postma proves that going back to first principles and factoring in the energy inertia and insolation of night and day plus adiabatic physics explains the missing 33K of heat that GHE religionists say is accounted for by their mythical GHE.
Postma’s numbers prove that abandoning P/4 and the mess it creates by mixing linear and non linear numbers helps us find that ‘missing’ 33K such that we no longer need to factor in any GHE to still get the same total energy budget. Thus we see the following:
Predicted earth emission without a greenhouse effect: 239 W/m²
Actual earth emission WITH a (supposed) greenhouse effect: 239 W/m²
Thus the GHE is a tautology premised on the back radiation meme which can be now be discarded by application of the principles of Occam’s Razor i.e. if you can explain reality without it then abandon it.
Let all ye who are ideologically pure reconcile the following:
“The only current ‘evidence’ for blaming carbon emissions are scientific models… Historically, science has not progressed by calculations and models, but by repeatable observations. Some theories held by science authorities have turned out to be spectacularly wrong… For excellent reasons, we have much more confidence in observations by several independent parties than in models produced by a small set of related parties!” ~David Evans
“To give an idea of how strong this enhanced cooling mechanism is, if it was operating on global warming, it would reduce estimates of future warming by over 75 percent. At least 80 percent of the Earth’s natural greenhouse effect is due to water vapor and clouds, and those are largely under the control of precipitation systems. Until we understand how precipitation systems change with warming, I don’t believe we can know how much of our current warming is manmade. Without that knowledge, we can’t predict future climate change with any degree of certainty.” ~Dr. Roy Spencer
“All temperature and weather observations indicate that the earth isn’t like a greenhouse and that there is in reality no ‘natural greenhouse effect’ which could warm up the earth by its own emitted energy and cause by re-emission a ‘global warming effect’. With or without atmosphere every body looses heat, gets inevitably colder. This natural fact, formulated by Sir Isaac Newton in his ‘cooling law’, led Sir James Dewar to the construction of the ‘Dewar flask’ to minimize heat losses from a vessel. But the most perfect thermos flask can’t avoid that the hot coffee really gets cold. The hypothesis of a natural and a man-made ‘greenhouse effect’, like eugenics, belongs to the category ‘scientific errors,” ~Dr. Wolfgang Thuene
Looks like the ranks of that “minority” that doesn’t believe there’s a GHE are swelling by the minute.
Dr. Wolfgang Thuene is right.
But ‘scientific errors’ seem to have been planned as a way to unite nations and avoid the threat of mutual nuclear annihilation:
http://dl.dropbox.com/u/10640850/20110722_Climategate_Roots.pdf
The most important issue facing us today is finding a path out of this conflict to harmony:
http://dl.dropbox.com/u/10640850/20110815_Climategate_Harmony.pdf
Except Spencer believes what the Slayers deny. reconcile that with your support for them
I have a question, most probably very stupid, but I’ve tried a couple of times, without a real answer. I’ve seen it asked at WUWT, also with no real answer.
Two planets. Both are pretty much like Earth, same position, same albedo, same day and night speed, everything equal, but without atmosphere. One of them magically maintains oceans, like Earth. Maybe it has a plastic cover over them, or something. The other one is a rock planet, without water.
The question is, would we expect them to have the same mean temperature, or to see a significant difference. In the later case, why?
Sorry if it’s been answered and I lost it. I have read quite a few comments at the many Skydragon’s threads, but far from all. Not even all in this thread.
plazaeme,
I can’t guarantee that I could answer but first could you indicate the motivation. Are you concerned about heat transport which the existence of the ocean may permit, or are you concerned about IR emissivity which is likely to be higher for the ocean than for a rocky surface, or something else?
Alex
Differential heating between equator and poles would drive ocean circulation, which would spread heat more efficiently around the globe, and thereby cause it to radiate less efficiently. (The T^4 radiation law means that hot spots can increase outward radiation far more than the corresponding cold spots reduce it.) The planet with oceans would be slightly warmer on average.
Although given that the average surface temperature would be -20 C, you would need some more magic to stop it freezing solid and turning into your rocky body solution.