Guest Post by Ira Glickstein
Solar “light” radiation in = Earth “heat” radiation to Space out! That’s old news to those of us who understand all energy is fungible (may be converted to different forms of energy) and energy/mass is conserved (cannot be created nor destroyed).
My Visualizing series [Physical Analogy, Atmospheric Windows, Emission Spectra, and Molecules/Photons] has garnered almost 2000 comments, mostly positive. I’ve learned a lot from WUWT readers who know more than I do. However, some commenters seem to have been taken in by scientific-sounding objections to the basic science behind the Atmospheric “Greenhouse Effect”. Their objections seemed to add more heat than light to the discussion. This posting is designed to get back to basics and perhaps transform our heated arguments into more enlightened understanding :^)
As I’ve mentioned before, during my long career as a system engineer I’ve worked with many talented mathematical analysts who always provided precise results, mostly correct, but some precisely wrong, usually due to mistaken assumptions. I got into the habit of doing a “back of the envelope” calculation of my own as a “sanity check” on their results. If their results matched within reasonable limits, I accepted them. If not, I investigated further. In those days my analysis was really done using a slide rule and scrap paper, but I now use spreadsheets.
The graphic above is based on an excellent spreadsheet from http://serc.carleton.edu/files/introgeo/models/mathematical/examples/XLPlanck.xls. It uses Planck’s Law to calculate the black body radiation spectrum from the Sun, as observed at the top of the Earth’s Atmosphere. It also may be used to calculate the radiation spectrum from the Earth System (Atmosphere and Surface, see below for explanation) at any assumed temperature. (I will refer to this spreadsheet as “Carleton” in this posting.)
I modified the Carleton spreadsheet to compute the mean Solar radiation per square meter absorbed by the Earth System, which turns out to be 240 Watts/m^2. I then used the spreadsheet to determine the effective mean temperature of the Earth System that would emit an equal amount of energy to Space, and that turned out to be 255 Kelvins (-18ºC which is 1ºF).
Since the mean temperature at the surface of the Earth is 288 Kelvins (+15ºC which is 59ºF), that leaves 33 Kelvins (33ºC which is 58ºF) to be accounted for. Guess how we acount for it?
The yellow curve (above left) shows that Solar radiation is in a tall, narrow “shortwave” range, from about 0.1μm (microns, or millionths of a meter) to about 4μm, which we call ultra-violet, visual, and near-infrared. The vertical axis is Intensity of the radiation, measured in Watts/m^2/μm, and the horizontal axis is Wavelength, measured in μm. If you divide the area under the yellow curve into vertical strips, and add up the total area, you get 240 Watts/m^2.
Since we humans sense the visual portion of this radiation as “light”, that is the name we give it, and that has led to the false assumption that it contains no “heat” (or “thermal”) energy.
The violet curve (above right) shows that, assuming a mean temperature of 255 K, Earth System radiation to Space is in a squat, wide “longwave” range, from about 5μm to beyond 40μm, which we call mid- and far-infrared. If you divide the area under the violet curve into vertical strips, and add up the total area, you get the same 240 Watts/m^2 as is under the yellow curve.
DETAILED EXPLANATION
The graph on the left shows the actual observed Solar radiation spectrum (in red) as measured at the top of the Atmosphere. It is superimposed on a black body model (in blue) showing very good correlation. Thus, while the Sun is not exactly a black body, it is OK to assume it is for this type of “sanity check” exercise.
If you calculate the area under the curve you get about 1366 Watts/m^2. That means that a square meter of perfect black body material, held perpendicular to the Sun, would absorb 1366 Watts.
However, the Earth is not a perfect black body, neither is it a flat surface perpendicular to the Sun! So, to plot the yellow curve at the top of this posting, I had to adjust that value accordingly. There are two adjustments:
- The Earth may be approximated as a sphere, with the Sun shining on only half of it at any given time. The adjustment factor for this correction is 0.25.
- The albedo (reflectiveness) of the Earth system, primarily clouds and light-colored areas on the Surface such as ice, causes some of the Solar radiation to be reflected back out to Space without contributing any energy to the Earth System. The adjustment factor for this correction is 0.7.
After applying these adjustments, the net Solar energy absorbed by the Earth System is 240 Watts/m^2.
The graph on the right shows the black body model for an Earth System at a mean temperature of 255 K, a temperature that results in the same 240 Watts/m^2 being emitted out to Space.
Of course, the Earth System is not a perfect black body, as shown by the graph in the upper panel of the illustration below, which plots actual observations from 20 km looking down. (Adapted from Grant Petty, A First Course in Atmospheric Radiation, Figure 8.2, http://www.sundogpublishing.com/AtmosRad/Excerpts/index.html.)
The actual measured radiation is the dark squiggly curve. Note that it jigs and jags up and down between the topmost dashed curve, which is the black body spectrum for a temperature of 270 K and a lower dashed curve which is the black body spectrum for 230 K. This data was taken over the Arctic, most likely during the daytime. The Petty book also has a graph looking down from over the Tropical Pacific which ranges from 300 K down to 210 K. Observations will vary by tens of degrees from day to night, summer to winter, and Tropical to Polar.
However, it is clear that my result, based on matching 240 Watts/m^2, is within a reasonable range of the true mean temperature of the Earth System as viewed from Space.
NOTE ABOUT THE ABOVE ILLUSTRATION
WUWT readers will notice some apparent inconsistencies in the graphs above. The top and bottom panels, from Petty, peak at 15μm to 20μm, while the purple, blue, and black curves in the middle panel, and the Earth System curves from the Carleton spreadsheet I used (see above) peak in the 9μm to 11μm range. Also, the Petty black body curves peak at a “Radiance” around 100 mW/m^2/sr cm^-1 while the black body curves from Carleton peak at an “Intensity” of around 14 W/m^2/μm. Furthermore, if you look closely at the Petty curves, the labels on the black body curves are mirror image! What is going on?
Well, I know some of the reasons, but not all. (I hope commenters who are more fluent in this than I am will confirm my explanations and provide more information about the differences between “Radiance” and “Intensity”.) I have Googled and Wikied the Internet and am still somewhat confused. Here is what I know:
- The horizontal axis in Petty’s plots are what he calls “Wavenumber”, increasing from left to right, which is the number of waves that fit into a cm (centimeter, one hundredth of a meter).
- This is proportional to the frequency of the radiation, and the frequency is the inverse of the wavelength. Thus, his plots are the mirror image of plots based on wavelength increasing from left to right.
- The spreadsheet I used, and my previous experience with visual, and near-, mid-, and far-IR as used in military systems, always uses wavelength increasing from left to right.
- So, when I constructed the above illustration, I reversed Petty’s curves, which explains why the labels on the black body curves are mirror image.
- Fortunately, Petty also included a wavelength legend, which I faithfully reproduced, in non-mirror image, at the top of each plot.
But, that still does not explain why the Petty black body curves peak at a longer wavelength than the Carleton spreadsheet and other graphics on the Internet. I tried to reproduce Petty’s blackbody curves by multiplying the Carleton values by the wavelength (μm) and that did not move the peak to the right enough. So, I multiplied by the wavelength again (μm^2) and, voila, the peaks agreed! (I hope some WUWT reader will explain why the Petty graphs have this perverse effect. advTHANKSance!)
ANSWERING THE OBJECTIONS TO BASIC ATMOSPHERIC “GREENHOUSE EFFECT” SCIENCE
First of all, let me be clear where I am coming from. I’m a Lukewarmer-Skeptic who accepts that H2O, CO2 and other so-called “greenhouse gases” in the Atmosphere do cause the mean temperature of the Earth Surface and Atmosphere to be higher than they would be if everything was the same (Solar radiation, Earth System Albedo, …) but the Atmosphere was pure nitrogen. The main scientific question for me, is how much does the increase in human-caused CO2 and human-caused albedo reduction increase the mean temperature above what it would be with natural cycles and processes? My answer is “not much”, because perhaps 0.1ºC to 0.2ºC of the supposed 0.8ºC increase since 1880 is due to human activities. The rest is due to natural cycles and processes over which we humans have no control. The main public policy question for me, is how much should we (society) do about it? Again, my answer is “not much”, because the effect is small and a limited increase in temperatures and CO2 may turn out to have a net benefit.
So, my motivation for this Visualizing series is not to add to the Alarmist “the sky is falling” panic, but rather to help my fellow Skeptics avoid the natural temptation to fall into an “equal and opposite” falsehood, which some of those on my side, who I call “Disbelievers”, do when they fail to acknowledge the basic facts of the role of H2O and CO2 and other gases in helping to keep temperatures in a livable range.
Objection #1: Visual and near-visual radiation is merely “light” which lacks the “quality” or “oomph” to impart warmth to objects upon which it happens to fall.
Answer #1: A NASA webpage targeted at children is sometimes cited because they say the near-IR beam from a TV remote control is not warm to the touch. Of course, that is not because it is near-visual radiation, but rather because it is very low power. All energy is fungible, and can be changed from one form to another. Thus, the 240 Watts/m^2 of visible and near-visible Solar energy that reaches and is absorbed by the Earth System, has the effect of warming the Earth System exactly as much as an equal number of Watts/m^2 of “thermal” mid- and far-IR radiation.
Objection #2: The Atmosphere, which is cooler than the Earth Surface, cannot warm the Earth Surface.
Answer #2: The Second law of Thermodynamics is often cited as the source of this falsehood. The correct interpretation is that the Second Law refers to net warming, which can only pass from the warmer to the cooler object. The back-radiation from the Atmosphere to the Earth Surface has been measured (see lower panel in the above illustration). All matter above absolute zero emits radiation and, once emitted, that radiation does not know if it is travelling from a warmer to a cooler surface or vice-versa. Once it arrives it will either be reflected or absorbed, according to its wavelength and the characteristics of the material it happens to impact.
Objection #3: The Atmospheric “Greenhouse Effect” is fictional. A glass greenhouse works mainly by preventing or reducing convection and the Atmosphere does not work that way at all.
Answer #3: I always try to put “scare quotes” around the word “greenhouse” unless referring to the glass variety because the term is misleading. Yes, a glass greenhouse works by restricting convection, and the fact that glass passes shortwave radiation and not longwave makes only a minor contribution. Thus, I agree it is unfortunate that the established term for the Atmospheric warming effect is a bit of a misnomer. However, we are stuck with it. But, enough of semantics. Notice that the Earth System mean temperature I had to use to provide 240 Watts/m^2 of radiation to Space to balance the input absorbed from by the Earth System from the Sun was 255 K. However, the actual mean temperature at the Surface is closer to 288 K. How to explain the extra 33 K (33ºC or 58ºF)? The only rational explanation is the back-radiation from the Atmosphere to the Surface.
Joel
I see that you have run out of science. Your response to my enquiry is disappointing to put it mildly.
I readily ackowledge that I am skeptical of the the entire AGW theory (for many reasons some of which are outside the ambit of this article). I consider that any genuine scientist would be (after all that is the scientific approach to any theory). In holding this view, I am quite prepared to acknowledge that the GHG ‘theory’ is superficially attractive. I understand the superficial attractiveness behind the proposition that the atmoshpere contains some gases that are largely transparent to incoming solar radiation and therefore the majority of this solar radiation finds its way through the atmosphere to the surface whereupon it heats the surface and this heat is, inter alia, radiated from the surface at a different wavelength at which wavelength the atmosphere (or some gases within the atmosphere) is not transparent such that some of this radiated enerrgy is ‘trapped’ thereby effectively warming the planet. Such a proposition is not difficult to understand and has a certain superficial attractiveness. I do not find the CAGW argument to be superficially attractive given that we are here some 4 1/2 billion years after the planet was formed during which time there have been significant climatic changes (far exceeeding those presently happening) and in particular times when CO2 has been about 1000 times higher without catastrophic effect. This suggest that it is extremely unlikely that there are tipping points such that I find the CAGW argument to be superficially unattractive.
Of course, whether an argument is superficially attractive or unattractive does not mean that it is right or wrong merely that it has a simplistic attraction or not.
There are many factors that go to the heart of the global warming theory. One of these is whether radiation emitted by a colder object is actually absorbed by a warmer object (and thereby increasing the radiation that the warmer object thereby emits).
The relevant equations have (several times) been set out above but they do not answer the question whether radiation only flows from hot to cold, or whether it is a two way street but with net flow from hot to cold. In particular, they do not answer the question whether a hotter object actually absorbs radiation emitted by a colder object and if so what effect this has on the hotter object and what becomes of the radiation so absorbed by the hotter object.
If radiation emitted from a colder object is actually absorbed by the hotter obeject then some fingerprint (signal) of this should be discernible. It seems to me that some physical expirementation should be carried out with a view to finding this fingerprint (signal) to try and ascertain whether it exists or not.
Hopefully some grown up scientists will not simply assert that “It may be that the moon is made out of green cheese. It may be that the sky is pink with purple polka dots when we are not looking at it and only turns blue when we look.” but will instead conduct some real science so as to try and answer these unknown and unanswered scientific questions.
Rhetorically you ask: “Why should scientists waste their time responding to people who are just completely ignorant of the science?” I would say that if their response is along the lines of your post (Joel Shore says:May 14, 2011 at 9:55 am) not only should you not wast your time but you should not waste my time engaged in reading such a childish rant.
Lets see the science. Your latest repsonse does not do your cause any good still less does it take the dabate forward.
Joel Shore says:
May 13, 2011 at 12:20 pm
“the greenhouse effect reduces the rate of energy loss out into space (for a fixed surface temperature), requiring a higher average surface temperature to restore radiative balance.”
So where does the energy to get this higher surface temperature come from?
Brian
I fully endorse the sentiments expressed in your comment “Bryan says:
May 14, 2011 at 8:35 am”
Not only are the posters (or vast majority of them) on this site entirely genuine, they are the people who are expected to make the (immense) sacrifices and dig (deeply) into thier pockets should political governace force through a policy of (attempted) mitigation to the (percieved) threat of manmade global warming such that it is necessary that the scientific community carries these people with them on the journey to the sacrificial altar.
The recent comments by Joel show why the public is tiring of this policy agenda and why they are no longer prepared to take this dogmatic mantra at face value.
Although I’ve not posted to this thread for a while, I have been reading the back and forth discussion and I thank all who have evidenced a sincere desire to learn and teach and solidify our knowledge in this area. The science is NOT settled, however, there are, IMHO, several facts that are, within reasonable limits, well proven.
I, like most of us here, am not in a position to make original scientific observations or do lab experiments, so I have to depend upon others. However, I follow the “trust but verify” dictim of President Ronald Reagan. I trust the experimental and theoretical work of credentialed scientists, but only if their data and theories pass a “sanity check” based on my own observations and experiences and common sense. Of course, I know will likely be off by some percentage. So, if the “experts” values agree within reasonable limits, I will accept them. If not, I will investigate further.
I think my postings to WUWT demonstrate quite clearly that I do not trust what the official climate Team says any further than I can toss a piano. Indeed, having personally read each and every one of the emails liberated from the Climategate Research Unit at East Anglia in the UK and all the Freedom of Information emails from NASA-GISS in New York, it is clear to me some of those scientists have violated their ethical obligations to both science and we taxpayers who fund their work by “cooking the books” to fudge and bend the data, often beyond the breaking point.
The Team has an agenda. It is the promotion, by whatever means necessary, of the idea that we humans are endangering all life on Earth by burning excessive quantities of fossil fuels and altering the terrain to reduce the albedo of the Surface in a way that will lead to a “tipping point” and near-term catastrophe for all of us.
I am confident that the idea of Catastrophic AGW – CAGW is totally discredited. We are not and never have been near any “tipping point”. While some or perhaps all the members of the official climate Team may have sincerely believed their CAGW nonsence a decade or two ago, I believe it has no current justification whatsoever. Those scientists who cling to CAGW are either trying to justify their past errors, keep government funding for their livelihoods, and/or are deluding themselves to the point of mental aberration.
On the other hand, as this Visualizing series indicates, I do accept the basic science of the Atmospheric “greenhouse effect”, as do my fellow Skeptics Tim Folkerts, Dave Springer, David M. Hoffer, and others, along with Warmist Joel Shore. I do respect several commenters in this thread who lean towards the “Disbeliever” side and have asked pointed questions in a civil and constructive tone. I think they are really open to being convinced of the basic science, at least in some form. Others, I am sad to say, have evidenced absolutely no desire to be constructive. While I accept the sincerity of the latter group, I am saddened to see them sucked in by scientific-sounding “evidence” that is, at least IMHO, easily refuted.
OK, so what real evidence to I have? What facts have I verified? Where is the proof?
Claim 1: The mean temperature near the Earth Surface is about 288 K (15ºC or 59ºF).
Evidence: The average temperature for various locations worldwide is available on the Internet. In particular, the published mean temperature is about 72ºF where I now live in Florida, about 55ºF where I was born and raised in Brooklyn, and about 45ºF where I spent my working years in upstate New York. Based on eyeballing temperatures in other places, it is clear to me that the mean temperature of the Earth Surface is somewhere between 50ºF and 70ºF so the official accounting of 59ºF (288 K) passes my “sanity check” and I accept it, with the proviso that it may be off by a degree or two in either direction. Any objection to that?
Claim 2: Solar energy enters the Top of the Atmophere (TOA) as radiation. It is in the visual and near-visual range and amounts to 1366 Watts/m^2. It is a good approximation of black body radiation from a source at approximately 5880 K.
Evidence: Well, from the Bottom of the Atmosphere (BOA) I can personally see the “visual” part. I know from personal experience with sunburn that the ultra-violet is associated with Sunlight and from work on military projects that the near-infrared spectrum is real. I trust the NASA measurements from the TOA looking towards the Sun (second graphic above). That jaggy curve, when compared to a 5880 K black body model, shows good agreement. Any objection to that?
Claim 3: The Earth Surface emits radiation towards the Atmosphere. The radiation depends upon temperature to the fourth power. The radiation varies, for each location, between day and night, the seasons, and whether from sea or land. While not identical to a black body, mean Earth radiation towards the Atmosphere is quite close to the theoretical ideal of a 288 K black body.
Evidence: All material at a temperature above absolute zero (0.0 K) emits radiation according to its temperature and emissivity. The Earth Surface has an emissivity in the mid- and far-infrared that has been measured at over 0.98 for the oceans and over 0.95 for most land areas. A perfect black body has an emissivity of 1.0. Thus the Earth Surface will emit energy to the Atmosphere very similar to that of a black body at about 288 K. Any objection to that?
Claim 4: Mean Solar energy input absorbed by the Earth System is about 240 Watts/m^2. Therefore, since energy may leave the Earth System only by radiation out to Space, the mean energy output of the Earth System is about 240 Watts/m^2.
Evidence: Simple geometry shows that the ratio between a disk the radius of the Earth and the surface area of the Earth is 1/4 = 0.25. The albedo (reflectivity) of the Earth System is about 30%, so about 0.7 of the Solar energy intercepted by the Earth System is absorbed. 1366 x 0.25 x 0.7 = 240 Watts/m^2. Almost all the energy input to the Earth System is Solar. Heat from the hot core and nuclear radiation amount to far less than 1%. Any objection to that?
Claim 5: Of the 240 Watts/m^2 absorbed by the Earth System, about 70 Watts/m^2 is absorbed by the Atmosphere and about 170 Watts/m^2 by the Surface.
Evidence Various Internet sources. Any objection to that?
Claim 6: The energy content of the radiation from the Atmosphere to Space approximates the energy radiated by a black body at about 255 K (-18ºC or -1ºF).
Evidence:The Perry curve from Space looking down (top panel of third illustration in this posting) shows actual measured radiation from the Atmosphere to Space taken in the Arctic. While it is clearly NOT a black body curve, a casual observer can see that it jig-jags between 230 K and 270 K. A similar Perry curve from the Tropics shows a jig-jag from 210 K to 300 K. An observer can look at both Perry curves and mentally spread the area of the curve above the 260 K dashed line down to fill in the open areas below the 250 K dashed curve. This is “sanity check” evidence that the equivalent black body model of the Earth System, as observed from Space, is between 250 K and 260 K. Thus, 255 K is in the right ballpark. Any objection to that?
Claim 7: The black body model for 288 K would emit about 390 Watts/m^2 while that for 255 K would emit about 240 Watts/m^2.
Evidence: The black body model in the Carleton spreadsheet gives those approximate values. Any objection to that?
Claim 8 The net convective and water cycle energy input is from the Surface to the Atmosphere and totals about 100 Watts/m^2.
Evidence Internet sources. For example, Trenberth gives 24 Watts/m^2 for “Thermals” and 78 Watts/m^2 for “Evapo-transpiration” for a total of 102 Watts/m^2. Any objection to that?
Claim 9: Accounting.
(a) 390 Watts/m^2 = Radiative energy input from the Surface to the Atmosphere (claim #7).
(b) 70 Watts/m^2 = Radiative energy input from the Sun to the Atmosphere (claim #5).
(c) 100 Watts/m^2 = Net convective and water cycle input from the Surface to the Atmosphere (Claim #9).
(d) 560 Watts/m^2 = Total input to the Atmosphere from all sources.
(e) 240 Watts/m^2 = Output of the Atmosphere towards Space (claim #4).
(f) 320 Watts/m^2 = Atmospheric emission towards the Surface (simple arithmetic: 560 – 240 = 320).
Evidence: Simple arithmetic. Close enough for a “sanity check”. Any objection to that?
BOTTOM LINE: If you seriously object to any item in my list of claims and evidence please state your alternative parameters and evidence, citing my claim number to make it more convenient for all to evaluate your objections. I expect that some of these numbers may be off by 10% or more in either direction. My purpose is not to obtain exacting results — I leave that to the supposed “experts” — but simply to be sure the “experts” are in the right ballpark. If you cannot state clear objections, I believe you must accept that about 320 Watts/m^2 is being output from the Atmosphere in the form of radiation and being absorbed by the Surface. QED. Any objection to that?
jae says:
May 14, 2011 at 9:53 am
Most fascinating and intriguing! So Ferenc is still in the game, and my SUV may not be guilty of anything, after all? How come we don’t hear from Ferenc anymore?
This certainly fits my observations that the temperature at various places on the Planet don’t seem to have anything to do with the quantity of GHGs in the atmosphere above those places, even when altitude and latitude are the same.
—
Isn’t that? Came to me one night while slipping between dreams, then it hit me. Got up, multiplied 390 by 5/6 and said, of course, the rest just started to fall in place. Now that finally makes some scientific sense to me. It took me close to seventeen months of sifting through the physics and it ends up being mainly simple geometry. Love that science, but it makes me feel a bit dense at the same time, why so long for such a simple principle. How could I overlook it for so long? Well, people like Tim, Joel, and I.P.C.C. is why, filling minds, like mine, with warped science logic in areas that really don’t matter.
Really, thanks for the reply! I wasn’t sure if anyone would really read this comment to you, and really “get” that approach, I though I thought that you would bee able if I could have you stop enough to grasp it. I’m like you, CO2, especially at these concentrations makes no scientific sense, even as hard as AGW based science tries, and I have yet for anyone as such to show one instance that it is the cause. Trouble is, what to do with such a thought out of the blue. Feel like writing a scientific paper but have little chance of being published. I’m in the middle of extending that to the other atmospheres, Venus, Titan, Mars, to see if it properly holds in all aspects and it does seem to hold so far. With this you can even extract the tau (optical thickness) of one bar pure CO2 from Venus’s atmospheric profile, super neat. As soon as I triple check the numbers I will post them here.
See where I am heading? If you can extract from Venus the influence of CO2 across 92 levels of one bar deep shells, logarithmic of course, then that same figure can be diluted to tell pretty close to how much CO2 influences our atmosphere as a whole with diluted CO2. My numbers so far show very small indeed, nearly, but not zero. The remaining influence must come from water vapor and I am working on that and all we are really speaking of is less that 6 Wm-2 even if our atmosphere were totally comprised of GHGs themselves, as Venus. That is what seems to be coming out of this, but I do want this to follow proper physics and radiative transfer keeping out of areas which do not really even apply if you can approach it correct. I have never thought of something so drastically new in science even after forty years of constant following and learning. I keep saying someone surely has already thought of this but I find it nowhere. Have you?
Seemed you might be able to help for if you can follow the areas where you have been arguing with Joel, you know enough to see this. So I chose you. Willing to follow on as I get deeper? (didn’t want to write 50 paragraphs if no one was even listening or cared)
Sky
Whilst I stand to be corrected, (save that I have some reservation with exchange) my perception of matters is much along the lines of your post at May 14, 2011 at 2:08 pm
Ira…
If you cannot state clear objections, I believe you must accept that about 320 Watts/m^2 is being ouput from the Atmosphere and being absorbed by the Surface. QED. Any objection to that?
—
Absolutely object unless you also say that any radiation accepted by the surface (left T in SB) from the atmosphere itself (right T in SB) originally came from the surface and has absolutely ZERO effect on any temperature, surface or atmosphere. SB handles it perfectly just from the two T’s. You seem to keep taking the right temperature and saying it’s possible power is special, it matters even though the temperatures do not change at all, sorry Ira, right there you are wrong. Don’t feel alone, seems David, Joel, and Tim, maybe Phil., seem to agree with you.
The two temperatures plus an optional emissivity properly handles the energy power at that interface just fine. Net energy never flows from cool to warm. You can imagine gazillion photons going back and forth with no change in either temperature, fine, I can imagine that too, it may even be real, by quantum amplitudes and probabilities, it may really not, but none of that really matters in this entire discussion in these five posts. If you continue to say it matters then I will continue to say I object, only the temperatures matter in a macro environment and our climate system is a macro system.
“Joel Shore said on Visualizing the “Greenhouse Effect” – Light and Heat
May 13, 2011 at 6:52 pm
However, the point I am making is that this does not mean that colder objects don’t radiate toward warmer objects. It only means that the colder object will always absorb more radiant energy from the warmer object than warmer object absorbs from the colder. That is what the real 2nd Law says.”
Alleyne replies:
Perhaps it would be useful if I set out the definitions of the terms I am using, and how I understand them
Temperature is the proxy for the energy state of an object.
The energy state of an object is defined by the Boltzmann distribution of its molecules.
Heat is the manifestation of the transfer of energy from an object at a higher energy state to one at a lower energy state.
Spontaneous means not needing to be driven by work of some kind (Water flows downhill spontaneously)
Heat/energy always travels from a higher temperature/energy state to a lower one.
Heat/Energy can not be transfered from a colder/lower energy state to a warmer/higher energy state without the application of external work/energy (Clausius’s Law) (Water won’t flow uphill without being pumped)
This is where I am having the difficulty with what you and Tim are saying. I have no problem with the energy traveling from the surface (warmer) to the atmosphere (colder). What I am having a hard time accepting is the energy being transferred from the atmosphere (colder) to the surface (warmer).
Based on your theory, we could build and engine with the surface as a hot source and the atmosphere as a cold sink, and run the engine to produce some work. In the process we discard some of heat/energy into the cold sink, as is required by Clausius’s Statement and the 2nd law. Now the clever part of the design is that we direct all but 1/10,000th of a percent of the energy radiated from the cold sink (atmosphere) back to the hot source (surface), thereby returning all but 1/10,000th of a percent of the energy we discarded into the cold sink. This respects the second law, according to you, because the NET entropy increases.
It also very significantly increases the efficieny of our engine.
However it doesn’t appear to respect Carnott’s Law.
I agree that a colder object can radiate towards a warmer object. I agree that a colder object will warm up due to the radiated energy from a warmer object.
However, if a warm object absorbs radiant energy from a colder object, this implies that the lower energy state is somehow able to raise the higher energy state to an even higher energy state. This is the part I am having difficulty with…
“Joel Shore said on Visualizing the “Greenhouse Effect” – Light and Heat
May 13, 2011 at 6:52 pm
“It is just that (for a given earth surface temperature) the heat flow away from the earth is less than it would be if the (IR-absorbing) atmosphere were not present. As a result, the earth’s surface temperature must increase until it reaches a point where the earth system (earth + atmosphere) is radiating back into space as much energy as it receives from the sun.”
Alleyne replies:
If on the other hand you mean that the GHGs act like insulation which slows the heat loss from the surface, I would have to think about that, but can’t at this point disagree that it is possible. However the backradiation “heating” the surface is not necessary in this scenario.
“Joel Shore said on Visualizing the “Greenhouse Effect” – Light and Heat
May 13, 2011 at 6:52 pm
Read this 20 times until you understand it so that you stop attacking “strawman” arguments and address what we are actually saying.”
Alleyne replies:
I am not attacking anything Joel, I am merely asking questions and making statements which, hopefully, will elicit informative responses so that I may understand your theory.
“Joel Shore said on Visualizing the “Greenhouse Effect” – Light and Heat
May 13, 2011 at 6:52 pm
But…you can’t define your spontaneous event as being just one part of the process. That won’t happen spontaneously. The point of the 2nd Law is that you can’t have the radiation from the colder object toward the warmer occurring without having the warmer object radiating toward the colder object too. Again, you seem to believe in the 2nd Law as some form of magic, rather than understanding the modern basis of it as following from statistical physics.”
Alleyne replies:
I was using spontaneous in the thermodynamic sense, as defined above, and because energy flows from hot to cold, the flow of energy from the surface to the atmosphere is spontaneous, whereas the energy flow from the atmosphere (ability of the atmosphere to heat the surface) is not spontaneous in the thermodynamic sense
“Joel Shore said on Visualizing the “Greenhouse Effect” – Light and Heat
May 13, 2011 at 8:54 pm
Alleyne: At this point, both Tim and I have patiently explained to you how the greenhouse effect does not violate the 2nd Law.
I’ll also point out that both of the major physics textbooks that we use in our introductory physics courses (one for the calculus-based course and one for the algebra-based course), popular texts used by hundreds…if not thousands…of colleges and universities to teach physics, contain discussions of the greenhouse effect and global warming. Don’t you think there would be an uproar in the physics community if the textbooks were teaching about things that violate the 2nd Law?
You have absolutely no credible shred of an argument left to believe that the greenhouse effect violates the 2nd Law. It is ludicrous to continue to make this argument…and, if you can’t understand why it doesn’t from our explanations, then you need to help us understand what your confusions are.”
Alleyne replies:
Thank you Joel, I am trying to help you understand my confusion, as you put it. As to the textbooks, there has been a lot of foolish stuff published in textbooks and the scientific concensus has been wrong more often than it has been correct – however that is not really germane to this discussion.
“Tim Folkerts said on Visualizing the “Greenhouse Effect” – Light and Heat
May 13, 2011 at 6:11 pm
For radiation between surface & atmosphere.
Looking specifically at the exchange between surface and atmosphere, the radiation rates are 350 W/m^2 up from surface to atmosphere and 324 W/m^2 down from atmosphere to surface, for a net 26 W/m^2 upward.
For the surface,
dS = – 26 J/ 285 K = – 0.091 J/K
The entropy of the atmosphere increases by
dS = +26 / 250 K = + 0.104 J/K
NET CHANGE from the process is +0.312 J/K – 0.274 J/K
= + 0.0.013 J/K
This is positive, as required.
(You could also use the 350 J & 324 J numbers directly, but that will give the same results).
I’ve actually given numbers to show entropy always increases as required. What specific example of a process with a net entropy decrease were you thinking of?”
Alleyne replies:
Thanks Tim for the numbers. Perhaps it is simplistic of me, or a further misunderstanding on my part, however I thought the formula for the change in Entropy was
dS= dCold – dHot
In other words the change in entropy was equal to the change of entropy in the cold sink less the change in entropy of the warm sink, therefore, using 356W/m^2 and 288K for the surface and 333W/m^2 & 253K for the atmosphere I got:
For 356J flux from the surface to the atmosphere:
decrease in entropy for the surface: -356J/288K = -1.236J/K
increase in entropy for the atmosphere: 356J/253K = 1.407J/K
dS for the surface to Atmosphere: 1.407J/K – (-1.236J/K) = 2.643J/K
For 333J flux from the atmosphere to the surface:
increase in entropy for the surface: 333J/288K = 1.156J/K
decrease in entropy for the atmosphere: -333J/253K = -1.316J/K
dS for the Atmosphere to the surface: -1.316J/K – 1.156J/K = -2.472J/K
Net dS = -2.472J/K – 2.643J/K = -5.115J/K
Which is a reduction in entropy and contrary to the 2nd law. I believe you have to calculate the effect of the energy flux on entropy in each direction and then sum them. If you were correct that it is the net which counts, then it could be calculated either way and arrive at your answer, but it doesn’t seem to work out that way.
Wayne, you object to my conclusion without showing where I went wrong in the simple arthmetic calculations and evidence that leads up to that conclusion.
You rely on your particular interpretation of a formula (which is a mathematical model and we all know howmodels can be incomplete or wrongly interpreted). How about the actual measurements of the radiation spectrum from the Atmosphere as measured by real instruments from the Surface looking up in the Arctic and the Tropics and other places that clearly shows hundreds of Watts/m^2 coming down towards the Surface from the Atmosphere?
You have faith in a mathematical model and in your personal interpretation of an equation, even though others in this thread have given you their, quite different, interpretations. And, your interpretation does not match actual instrumental measurements while theirs do!
And, you have faith in your interpretation which does not match my accounting based on multiple sources of actual instrumental measurements while theirs does!
Please have a close look at the Perry curve of radiation measured at the Bottom of the Atmosphere looking up (the lower panel of my third illustration in this posting) and explain what it is telling us in terms of your interpretation. advTHANKSance.
Ira
I am glad to see that you have come back with a summary. As previously mentioned, I find your articles amongst the most interesting posted on this site and the fact that this article has generated nearly 600 comments is testament to that. I thank you for the time spent compiling your articles.
As a general observation, a 10% error in some of the figures would more than produce the feared global warming of more than 2 degC per century. It is therefore important to know the correct figures within a better margin of error than 10% if we are to ascertain whether there may or may not be any significant warming.
Claim 1: I have considerable problems with this. If I was to go out into my garden on a summers day and record temperatures, I probably would find 100 or may be even a 1000 different temperatures. Many of these would vary by only relatively small amounts but some would vary by upwards of 40 degC. I live in semi rural conditions about 1 Km from the sea in the low foothills of the mountains. The mountains behind me begin in earnest about a further 1 km inland and extent about a further 20 or so km inland. In the early Spring, it may be 15 deg C by the coast but only 3 deg C in the mountains. The idea that temperatures for my area should be set by a thermometer at an airport some 60km away reading say 18 degC is fatuous and misconceived. Look at what Hansen does with large swathes of the Artic with only one or so station readings. To get a proper handle on the average global temperature we would need trillions of measurements. Obviously satellite measurements go some way to addressing this but even these are too course.
Further whilst the average surface sea temperature may be about 15 deg C, it is an over simplification to consider that over 70% of the earth’s surface is at the average sea surface temperature. One has to bear in mind the average temperature of the sea which is only about 4 deg C not its surface temperature (of about 15 degC) since the oceans are a heat sink with far more stored latent heat capacity than either the atmosphere or the the ground itself. The oceans are long term temperature drivers.
In summary, I think that there is good reason to be cautious with respect to the accuracy of the 288K figure.
Claim 2. If NASA TOA measurments ascertain incoming radiation at 1366 Watts/m^2, I would accept this.
Claim 3. Some caution is required. Actual measurements do not accord with actual measurements for Venus, Mars Titan or even the moon. The moon being devoid of an atmosphere ought to be the simplest to model but even this does not accord. See http://www.tech-know.eu/uploads/Greenhouse_Effect_on_the_Moon.pdf
Claims 4 and 5 . Potential for much error. The area, height (leading to volume) and compostion of clouds constantly varies 24 hours a day. No 2 days are the same. Nor are the location of clouds in the same place on any 2 days. It is difficult to know with reasonable precision what percentage of solar energy finds it way past the cloud shield so as to be able to warm the surface. Further the albedo of the surface is variable (not only from place to place but also from season to season) and therefore difficult to assess. Further there is an interaction between variation in cloud pattern and ground albedo, ie., it makes a difference whether the cloud window is open over surface areas which are more or less reflective. If clear skies are prevalent over areas that are more reflective of solar radiation one inevitable gets a different absorption. There is potential for considerable variation year on year with 4 and 5 and potential for much error in the assessment of these factors.
Claim 6. It is not a black body curve. See my comment under 3 above. Caution required with respect to interpretation.
Claim 7. This may be so, however, the issue is to what extent is it reasonable to consider the earth as if it were a black body when in fact it is, at best, a gray body.
Claim 8. This may be under estimated. Very difficult to perform accurate world wide measurements.
Claim 9. There is a deficiency in available empirical data to support the figures cited. (d) and (f) are interlinked and much more field studies are required to validate those figures and their order of magnitude.
There is no empirical data showing that about 320 Watts/m^2 is being ouput from the Atmosphere and being absorbed by the Surface, nor what the effect of that radiation has on the surface if so absorbed. It is difficult to envisage how 320 Watts/m^2 at a temperature of about 240K to 250K could be absorbed by the surface which is at about 288K. In making that latter statement, I am not excluding that the general temperature of the atmoshere (whatever that may be) does not slow down the heat loss from the surface or affect the height at which energy is radiated into space.
sky says:
This is, quite frankly, nonsense. Simple models of the greenhouse effect to illustrate it make certain approximations. However, more quantitative models do not ignore convective effect nor do they use the S-B Equation. It continually amazes me that people who have clearly never even read a textbook on the subject feel that they are experts on it nonetheless. The Dunning Kruger effect ( http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect ) is really in full force here.
richard verney says:
Do you think such experimentation to understand the basic laws of radiative physics has never been done?!?! If you want to understand the laws of radiative physics, I suggest that you go read about them. These are laws that are used everyday by physicists and engineers; they are the laws that govern the field of remote sensing; they are even the basic principles that explain our human metabolism. (Example: Why does a human feel comfortable naked in a room at a temperature of about ~25 C when, given our skin temperature, we emit radiation at a rate of several hundred Watts, much greater than our metabolic production of heat of ~100 W. The answer is because the net radiative flow is only about 100 W because the objects around us emit radiation that we absorb.)
Why do you think that people need to do additional experimental testing just because you aren’t yet convinced that they work?!? The people who actually use them sure as heck are convinced. If you want to learn more about the historical discovery of these laws and some of the original experiments done, be my guest…but don’t expect people to perform experiments for your benefit to show things that have been verified literally millions of times!
Even people on your side of the larger AGW debate have expressed admiration for my patience in dealing with you guys. Everyone else wonders why I even spend the time doing this.
Hans says:
It comes ultimately from the sun. The surface temperature of the earth is determined by the balance between what it receives from the sun and what it emits back out into space.
With respect to my latest post. I need to correct. This should read:
Claim 3. Some caution is required. Theoretical black body calculations do not accord with actual measurements for Venus, Mars Titan or even the moon. The moon being devoid of an atmosphere ought to be the simplest to model but even this does not accord. See http://www.tech-know.eu/uploads/Greenhouse_Effect_on_the_Moon.pdf
Alleyne
Many good points raised in your post of May 14, 2011 at 5:03 pm
“I agree that a colder object can radiate towards a warmer object. I agree that a colder object will warm up due to the radiated energy from a warmer object.
However, if a warm object absorbs radiant energy from a colder object, this implies that the lower energy state is somehow able to raise the higher energy state to an even higher energy state. This is the part I am having difficulty with…”
This is what I have been trying to say to Joel and Tim. I don’t see how the warmer body can actually absorb this radiation.
I don’t know what happens to the warmer body if it absorbs this radiation. It is difficult to envisage how the absorption of cold energy increases the energy state since surely the warm body will have to expend energy in warming up the colder photons towards the energy state of its own warm photons . This will then reduce the capability of the warmer object to emit photons, ie., the photons that it now emits will be slightly cooler than the photons that it was emitting prior to the absorption of the cold photons. Problem with that is that it is that it is akin to saying heat can flow from hot to cold and this is why I dont see that there can be absorption.
Alleyne says:
No…The Second Law talks about heat, which is a macroscopic concept representing the net flow of energy.
Why? How does the Second Law work in your picture of the world? Is there a little “Maxwell’s Demon” that stops a photon and asks where it came from and where is it’s going and says, “I am sorry, sir, but you can’t travel in this direction”? Do objects refuse to radiate if toward any hotter objects that they see or do the hotter objects just refuse to accept photons from objects that are colder?
Why do you believe your conception of the Second Law is correct and the conception of physicists, who actually work intimately with it and understand its derivation from statistical physics principles, is wrong?
Yeah…Well, that’s pretty clever but also impossible to implement. How do you direct the energy radiated from the cold sink back to the hot source without having the hot source radiate energy to the cold sink? That’s the whole point: Such a scenario is impossible. The Laws of Radiative Transfer, coupled with Kirchkoff’s Laws regarding emissivity and absorptivity guarantee that this can’t happen.
I think I see where you might be getting confused: You seem to think that I am just saying as long as some overarching process has flow from hot to cold, we can have different separable sub-processes that have flows in the other direction.
I am not saying that: What I am saying is that the spontaneous process of radiative heat transfer between two objects consists of two sub-processes: radiation from the hot object passing to the cold object and radiation from the cold object passing to the hot object. However, the sub-processes necessarily occur together; you can’t separately have one without the other. Try as you might, you will not be able to produce (without the input of work) the energy flow from the cold to the hot without necessarily having the larger energy flow in the other direction.
Of course, there are lots of clever ways that people like to imagine how they can get around this, which is why so many people seem convinced that they have invented a concept for a perpetual motion machine. If the Laws of Thermodynamics were not so subtle, it would be obvious that one couldn’t violate them. It is their very subtlety (particularly the 2nd Law) that makes it so tempting for people to believe that they can find a way around it if they are just a little bit more clever.
Yes…That insulation effect is essentially what is happening. So, if you want to describe it without reference to radiation passing from the atmosphere to the surface then I won’t object. (The fact is that the mechanism by which this insulation effect occurs is by radiation occurring in both directions, as can easily be verified by empirical observation. But if you just want to think about just the net heat flow because it violates your principles to imagine heat as the net result of energy flowing in both directions, then I won’t complain. Mathematically, the greenhouse effect comes out of the equations without labeling the terms as forward and back radiation. So, my advice to people who are hung up about the concept of “back radiation” to just forget about it and simply tell themselves that the heat flow away from the earth’s surface depends not only on the temperature of the earth’s surface but also the temperature of the atmosphere, which is what the radiative transfer equations basically express.)
Why would you jump to the conclusion that the physics textbooks are wrong on a very fundamental and basic matter of physics and that the scientific consensus is wrong in using equations that have been tested by scientists and engineers and used to build all sorts of technology rather than acknowledge that your own knowledge may be what is limited here?
Yes…You are misunderstanding. You have put in a negative sign so that you end up subtracting numbers that you should be adding. You correctly calculate changes in entropy and then, instead of adding them together to get the total change, you subtract one from the other.
Wayne:
Keep up your work.
I have always had a very strong hunch that there is something wrong with the conventional AGW/GHG-forcing view. For several reasons. First, because this planet has been around for a very long time and has sustained extreme variations in GHGs, without any kind of ghg-caused collapse–or even a hickup (meteors cause big hickups, but not OCO). Second, there has been absolutely no correlation between the increases of any GHGs and temperature, over a period of a couple of millenium or more. OR even in the past 15 years, LOL. Au contraire, many scientists are now even fearing a little ice age, again! Three, the temperatures are NOT higher in areas with very high levels of GHGs (e.g., Atlanta, GA) than in areas with very low levels of GHGs that are at the same latitude and altitude. This indicates that Planet Earth has a very good “thermostat” (WATER). See the posts by Willis Eschenbach.
Bottom line: there is ABSOLUTELY no empirical evidence for a GHE or CAGW. All three of the above reasons should be critical to a scientist: without empirical verification, the theory is junk. So far, all we have is junk science, wrt “climate change,” “global warming,” and even “warming due to addition of GHGs.”
THANKS again for your courteous and well though-out comments, and also for referencing them to my claim numbers. You are a gentleman and a scholar!
I agree that a 10% error in any of my numbers would invalidate any argument about the supposed 0.8ºC mean Surface temperature increase since 1880, or in how this increase should be allocated between natural and human causes. I think humanity might be responsible for perhaps 0.2ºC while the IPCC blames us for 0.5ºC or more. My accounting in the comment you are replying to sheds absolutely no light (or heat :^) on that issue.
But, that was not the point of my comment or this topic nor or my Visualizing series. Even if every one of my numbers is off by 10%, and all in the same direction, I do not think it is possible to conclude that there are not hundreds of Watts/m^2 of radiation coming down upon the Surface from the Atmosphere. Furthermore, if the errors in my accounting are relatively random, it is likely that some are in one direction and others to the opposite, so the final result is well within the 10 % error objective. Can you spot an error or different interpretation of my claims and evidence that would change the fact of hundreds of Watts/m^2 that must go from the Atmosphere to the Surface?
Also, Richard, in a previous posting you seemed to imply that radiation could come from a cooler body towards a warmer one and then, at the very doorstep, be rejected somehow because the radiation was somehow marked and detected as coming from a cooler object. How in the world of physics and engineering would this work? If you were very rich and I poor and you gave me $1000 and, out of gratitude, my wife baked you a $2 cake and took it over to your house, would it be rejected at your doorstep?
Of course that is true. If my doctor took 100 drops of my blood from many different parts of my body, each would have a different chemical analysis. Does that mean the doctor must check ALL my blood to make a diagnosis?
In an earlier comment you said the 288 K mean might be off by a degree or three. Say it is (and it may well be), how would that change my concusion that there are hundreds of Watts/m^2 coming down from the Atmosphere to the Surface? Not by much, would it?
Thanks!
Why talk about anything other than the Earth System? We know the measured emissivity of the Earth, both sea and land, is 0.97 or more, close enough to 1.0 (black body) that the radiation from a 288 K (+/- 3 :^) Surface will be well within a percent of the black body model.
Claim #4 depends upon the 1366 Watts/m^2 you already accepted from NASA measurement, plus simple geometry and an estimate of albedo. Yes, clouds and the resultant albedo change minute by minute in any given geographical location, but, but … BUT, if you average over the seasons of the year over the whole Earth Surface, these variabls will cancel out. And, evn if the actual mean albedo is 25% or 35% or 40%, how much will this change the 240 Watts/m^2 I calculated? Even a 10% error in average albedo amounts to only 24 Watts/m^2 and that will not do much, one way or the other, to change my accounting of hundreds of Watts/m^2 streaming down from the Atmosphere to the Surface? Will it?
As for Claim #5, which is what percentage of the 240 Watts/m^2 is initially absorbed by the Surface and how much initially by the Atmosphere, my percentages came from Trenberth and may therefore be suspect. But, we know that both Surface and Atmosphere absorb some of the Solar energy. If Trenberth assigned too much of it to the Surface to get more “back-radiation” and help his agenda, it would not change my results much. For example, he puts 168 Watts/m^2 to the Surface and 67 Watts/m^2 to the Atmosphere. If he really screwed up and the ratio is reversed, that would reduce my 320 Watts/m^2 from Atmosphere to Surface by 101 Watts/m^2. There would still be over 200 Watts/m^2 in downwelling radiation.
Right! I specifically said “While it is clearly NOT a black body curve, a casual observer can see that it jig-jags between 230 K and 270 K. …” However, the key to my accounting is the area under the curve. If the baker put icing on a cupcake and pooped it up in the middle and drooped it down at the sides to make it look like more, even a child could estimate what the real level would be if that icing was smoothed out.
So, please look at the Perry curve in this posting and the other one in his book that I had in a previous posting in this series, ane mentally smooth it out and tell me whether ir not it comes out between 250 K and 260K. If the 255 K I used is off by 5 K (or even 10 K) that will not affect the hundreds of Watts/m^2 downwelling as radiation from the Atmosphere to the Surface.
The emissivity of the Earth is over 0.97 and a perfect black body is 1.0 so, for all intents and purposes, the Watts/m^2 calculated by the Carleton spreadsheet based on Plank’s Law may be off by only a small number of Watts/m^2 and my main claim is that there are hundreds of Watts/m^2 streaming down from the Atmosphere, so a few Watts here or there is a drop in a bucket.
Agreed – this is another Trenberth-based estimate and therefore questionable. However, if it was half the Trenberth estimate, it would require me to decrease my accounting of downwelling radiation by only 50 Watts/m^2, a fraction of the hundreds I estimate. If Trenberth was off in the other direction, and the true coonvective and water cycle is double what he claims, that would actually increase my accounting of downwelling radiation by 100 Watts/m^2. So, either way, my statement that there are hundreds of Watts/m^2 in downwelling radiation from Atmosphere to Surface stands.
Sorry Richard, but I cannot see how any errors in my accounting (and I am sure there are some) could change the 320 by more than 50 in either direction. Even if I am off by 100 it remains true that there are hundreds of Watts/m^2 in downwelling radiation from Atmosphere to Surface. Can you see any way out of that?
Well, Richard, I too have difficulty accepting some of the truths of physics, but, after questioning them and doing a “sanity check” I sometimes have to accept them. Way back when a physics prof told us the laws of thermodynamics said you could not create energy out of nothing. Then, he said, it is even worse than that, you cannot even break even! I din not and do not like that, but, sadly, it is the truth.
By the way, I still do not accept the “Copenhagen interpretation” of quantum mechanics. I will go to the grave, as did Einstein, believing in strict determinism, despite the success of what Feynmann called “quantum wierdness”.
Thanks and I hope you reply to my comment.
richard verney:
You consider yourself a skeptic, I assume, and yet you accept any piece of garbage that you find on the internet? Hertzberg, Schreuder, and Siddons are well-known for being purveyors of pseudo-scientific nonsense. Why would you possibly believe their nonsense when you won’t accept real science that has been tested thoroughly? It seems like your skepticism is very selective.
Here is a detailed debunking of their paper: http://scienceofdoom.com/2010/06/03/lunar-madness-and-physics-basics/
richard verney wonders:
“I don’t know what happens to the warmer body if it absorbs this radiation. It is difficult to envisage how the absorption of cold energy increases the energy state since surely the warm body will have to expend energy in warming up the colder photons towards the energy state of its own warm photons . “
Maybe it would help to think on the microscopic level. Think about one atom and one photon at a time.
A photon — any photon — has energy. Energy is not “cold” or “warm”. Photons are not “cold” or “warm”.
When that photon hits an atom, that energy can be absorbed. The photon is destroyed, giving all its energy to the atom. It doesn’t matter how fast the atom is already moving (ie how “hot” the atom is). If the atom absorbs that photon, the atom will have more energy than before. If the photon is low energy, the atom will only gain a little energy (ie get a little hotter). If the photon is high energy, the atom will gain more energy (ie get a lot hotter).
The atom now has EXTRA energy to share with other atoms around it. It does not need the atoms around it provide energy to “warm up” the photon. Instead, it can share the energy the photon had with all he neighbors around, making all of them a little warmer.
(This is different than adding a cold atom to the other atoms. When a cold atom runs into warm atoms, the cold atom is not destroyed. The cold atom had low energy and will tend to gain energy, sapping the other atoms of energy and cooling then a bit.)
Ira:
“Any objection to that?”
Suggestion: by repeating this phrase over and over again, you appear to me (and probably many others) as an elitist, smart-assed, all-knowing, sacrosanct, etc. hack. Drop that attitude, please, since it turns some of your readers off.
Signed, JAE, PhD
Ira, I do understand that you do not trust what is going on but you also seem unwilling to let go, you know, the same old tack I have seen over the last month’s, some 600 papers, 3000 posts, quarter million comments later. It is not you but IPCC I blame. I understand you build your view on the latest peer-reviewed climate science and I don’t always. If you are comfortable with it, stay right where you are.
I will just point out the one fact of contention on the IR aspect of Trenberth’s chart, if I take an special averaging full spectrum radiometer to read Trenberth averaged “world” and point it at the ground, it says 390, I point it upward toward the cold atmosphere, all lines considered, it says 324, so what is going up from where I am standing, 390-324 or 66 Wm-2.
Why do you have trouble stopping there and quit trying to read into that 324 any more meaning, there is no further meaning to those numbers, read Trenberth’s papers, it’s data or derivatives of. It is just the screwy way the graphic was drawn that is the problem and you seem too to have bought into that whole logic. You seem to see the 324 Wm-2 coming from way up in the atmosphere, and, I see it located no more that a few meters off of the surface, just above my head except for the further reaching window frequencies.
Why does the ‘up’ reading not also say 390? Because it reads the frequency lines with various transparencies that allow that 66 W to escape from ground level upward (window) every second of every averaged day of every averaged year in Trenberth’s simple view of the world (not a cut to Trenberth here, the simplification must occur at this point with limited data and accuracies involved). If the atmosphere were totally opaque to all lines it would be like me, right now in my room, with everything 15 ºC and that is what SB would be showing, all temperatures locally are equal, net energy flow is zero. But, this never happens, even on Venus, there is always leaking upward and it has exactly the dependence of the total averaged optical thickness across all frequencies that determines that leakage that determines the temperatures of the layers above (gauging the natural lapse with H2O adjustments applied of course).
If you don’t like my words I can’t seem to help you if you will not get to the point where you see MY view clearly, I have seen yours for over a year now. I am no longer going to accept climate science’s consensus viewpoint. For whatever physicist I have in me I am now going simplify, simplify, simply down to some established principles in science that can not be questioned without dumping major laws and principles found true over the years. If I fail, well, so be it. I think I have said all of this before but there it is again. I just wish you could see my side, not agree but understand it..
Wave mechanics expert argued the same thing against quantum mechanics with a totally different way to look that matched the same data. I don’t ever want to conform, that is not what I do. The minute the consensus of the science world matches the data and I see why and that they are right, I am off to some other area of science that will challenge me. So far the consensus has been missing the data miserably so this is fertile ground to me. Think out of the box, their box is not working. Stop trying to get me to agree.
I wish I could converse with you over a beer or coffee, could give you so many different viewpoints, all proper in science (well, I do make mistakes), that tend to help me to get a real “feel” of the limits of the system and parameters. Have you taken the extremes yet? For instance, what would happen if the atmosphere if it were so opaque that only one watt per square meter of SW could reach the surface. What would Trenberth’s budget look like then? Heh? It’s calculable with optical thickness as you gauge (the units are mean free path). What would happen? You can plot various possibilities against the new bond albedo and get some rather surprising results. Try it, don’t ask for mine, I did it on a hand calculator. Such tests end up giving you a close approximation to what such changes would do to our atmosphere and your end up with a better “feel”.
To me that is science as I know it and I have been non-stop since college, I simply enjoy science, heavy on physics, I like to have a “feel” when available, as accurate as possible, so I can tell without much trouble sorting through important aspects and those that you can simply ignore or are irrelevant to the question. Why ignore? We only know albedo shy of two digits. I’ve seen in papers 29.x, 30,x. 31.x. Which is right, eh? And in reality there are really only four fairly accurate data points averages that really matter to begin with. I’ll chose to take a new tack on the problem every time. Just ignore me.
If you have a further reply, please don’t pick on a sentence out its entire context. I have not the time to make every single sentence stand on it’s own. That is the way I write when not making a firm point.
I’ve probably said way too much, made too many shortcomings in describing my thoughts, it happens.
jae, well you’ve got all of that right!
Thanks for giving that a look. I’ll stay on it, wouldn’t be able to get it out of my mind if I wanted to, not until I can find it is flawed. But it seems pretty sound so far and now I have to see if numerically reproduces the numbers correct for the other atmospheres if I can find enough available data to do so.
One other thing, did you notice that the relation I gave should holds true at any point on the globe, any season, any surface temperature just as Miskolczi’s relations hold for any time and place? It is a global relationship. Also 2 x 1/6 or 1/3 is the greenhouse effect constant mentioned in his papers. That also is curious. Thought that might have slipped by you.
Ira, I want to commend you for having these posts, I have gathered many things from them all, no doubt. Some are things that are “out there” to avoid like the plague, others some great thoughts and most of those are from reading between the lines of what others are saying. All of it is great (except maybe the petty bickering, but even there I find value).
You wrote nine points so here are some of mine that I find completely true:
#1) First Law of Thermodynamics
#2) Second Law of Thermodynamics
#3) A solid surface, solid or liquid, can never get it’s temperature raised by energy that originated from said surface and included in it’s temperature at a macro level, by conduction or radiation. (see #1 & #2)
#4) At a macro level once energy is within the atmosphere that portion of energy is committed to be ejected to space for the average atmosphere’s temperature is always lower with increased altitude. (See #2, #3)
#5) On the average the atmosphere is homogeneous and any component of energy transfer (components of a vector) horizontally is totally cancelable and can be reasonably considered zero at the local macro level.
#6 ) … and so on.
See, my thoughts are on proper physics without getting into whatever current climate science has morphed it into. If you really want to make a mark, if you truly care, help, stay in pure physics and I will step into the background, I have no ego to support, no visions of fame, I just want proper physics applied to all of this mess but insist on it.
Maybe you should have a series, with Anthony’s blessing of course, on one tiny question at a time, not trying to wrap the entire question of CO2 warming into one huge post. Always too messy, nothing ever seems to come from it.
For instance, one might be #3, it’s a good question for everyone to get their minds around. On the macro level I stand by my claim above. At the micro level that question goes off of the cliff. There are principles addressing that of whether entropy can be decreased momentarily or not at all. Can gray, a mixture of black and white particles, have a probability of actually turn into black and white again. That’s deep water but everyone needs to really know what happens at the macro scale of our climate system (and of course it is NO, period, according to today’s best science). Maybe delve into the exact reason why. One focused question at a time.
Maybe we could have some real science here answering real questions one by one. I am tiring of the arguing. This isn’t that hard. Climate science WANTS is to be EXTREMELY hard and complex and most know exactly why. Approach it with simplicity as all real physics is. If your 0.2 ºC is correct it will float to the top. I think it is less than that, it could be more, and will try to show and explain as I get the numbers, it will be using a breakdown of Venus’s atmosphere of pure CO2 to show why our atmosphere is acting the way it is but the number have to make sense and be correct.
Ira said /#comment-660443
May 14, 2011 at 7:45 pm
Also, Richard, in a previous posting you seemed to imply that radiation could come from a cooler body towards a warmer one and then, at the very doorstep, be rejected somehow because the radiation was somehow marked and detected as coming from a cooler object. How in the world of physics and engineering would this work? If you were very rich and I poor and you gave me $1000 and, out of gratitude, my wife baked you a $2 cake and took it over to your house, would it be rejected at your doorstep?
An analogy which has no bearing on the example being explained is worthless in science. To confuse the standard laws of science by creating a childrens’ story by personifying hotter and colder objects who have the ability to choose, is a fun project, but not science.
It is not the energy from the colder being rejected by the warmer, it is the colder taking from the warmer by imposing its nature on the warmer. The colder comes up to the doorstep, or they meet somewhere in the street, and shake hands; the warmer immediately loses heat to the colder who begins to warm up because that is the nature of their relationship.
That’s what the 2nd Law says because the process is not one of choice. For choice, one has to bring in another energy, work, to change the process. Therefore, Heat always flows from the hotter to the colder.
The claim that it is a “net” heat exchange from hotter to colder makes no sense in light of this. Just because ‘radiation can be emitted in all directions’, doesn’t mean it always is. The 2nd Law limits this possibility, or rather, articulates the limit.
Therefore, the ‘statistical net exchange of heat is from hotter to colder by including heat from colder to hotter’ is gobbledegook in science, because it violates the 2nd Law in its base premise.
The only net exchange going on is within the bounds of the 2nd Law; for example, when pouring hot water into a cup already half filled with cold water the first amount of hotter will have its heat taken by the colder so reducing its own and it then becomes the colder to the hot water coming after it, even while it is still hotter than the colder first in the cup still taking its heat – and so the net exchange in this to equilibrium.
If you claim that the 2nd Law breaks down at the level of photons, then you must prove it.
It would be worthy of a Nobel Prize for Physics for you to show that the tried and tested and well understood in Science 2nd Law breaks down at this level.
There are three of you here claiming it..
richard verney says:
May 14, 2011 at 6:14 pm
“This is what I have been trying to say to Joel and Tim. I don’t see how the warmer body can actually absorb this radiation.”
What other disposition is possible for the radiation moving from the cooler object to the warmer object? They must either be transmitted straight through, absorbed, or reflected. They can’t just disappear as that would violate conservation of energy. The books have to balance. Every quantum of energy must be accounted for.
The simple fact of the matter is that the warmer object throws off more photons than it receives from the colder object.
Imagine a wall with you on one side and me on the other. We are throwing tennis balls over the wall to each other. For the sake of argument lets say I can’t pick up and throw any faster than you so for every ball I throw over you throw one back at the same time. We are in tennis equilibrium. So now I get someone else to help me and for every ball you throw we throw two balls back. We’re the hotter team now and there is no tennis equilibrium any longer. But just because we can throw faster doesn’t mean you’ve stopped throwing. There a net transfer of tennis balls from the hotter to the colder team.
Radiative exchange between two objects of same or different temperatures works the same way. Both objects are absorbing energy from the other. If they are both the same temperatures the exchange is tit for tat and they are said to be in thermal equlibrium. If one is warmer than the other then there is a net transfer from warmer to colder: EnergyNet = EnergyOut – EnergyIn. For the colder object the net is a positive number and for the warmer object it’s negative. The transfer continues forever. It doesn’t ever stop. It simply reaches a point where EnergyOut = EnergyIn for both objects.
Why is that so difficult to accept? It is not at all counter-intuitive and is in fact exactly how radiative exchange works. It isn’t rocket science at this level. The rocket science starts when we start adding more objects with complex properties and transmission media with complex properties. But simple radiative exchange between two ideal bodies in a vacuum is very basic and very comprehensible.
@joel Shore
“The Dunning Kruger effect ( http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect ) is really in full force here.”
Arthur C. Clarke’s three laws of prediction are worth mentioning in this context:
1.When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
2.The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
3.Any sufficiently advanced technology is indistinguishable from magic.