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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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The greenhouse effect and the 2nd law of thermodynamics

What the science says...

Select a level... Basic Intermediate

The 2nd law of thermodynamics is consistent with the greenhouse effect which is directly observed.

Climate Myth...

2nd law of thermodynamics contradicts greenhouse theory

 

"The atmospheric greenhouse effect, an idea that many authors trace back to the traditional works of Fourier 1824, Tyndall 1861, and Arrhenius 1896, and which is still supported in global climatology, essentially describes a fictitious mechanism, in which a planetary atmosphere acts as a heat pump driven by an environment that is radiatively interacting with but radiatively equilibrated to the atmospheric system. According to the second law of thermodynamics such a planetary machine can never exist." (Gerhard Gerlich)

 

At a glance

Although this topic may have a highly technical feel to it, thermodynamics is a big part of all our everyday lives. So while you are reading, do remember that there are glossary entries available for all thinly underlined terms - just hover your mouse cursor over them for the entry to appear.

Thermodynamics is the branch of physics that describes how energy interacts within systems. That interaction determines, for example, how we stay cosy or freeze to death. You wear less clothing in very hot weather and layer-up or add extra blankets to your bed when it's cold because such things control how energy interacts with your own body and therefore your degree of comfort and, in extreme cases, safety.

The human body and its surroundings and energy transfer between them make up one such system with which we are all familiar. But let's go a lot bigger here and think about heat energy and its transfer between the Sun, Earth's land/ocean surfaces, the atmosphere and the cosmos.

Sunshine hits the top of our atmosphere and some of it makes it down to the surface, where it heats up the ground and the oceans alike. These in turn give off heat in the form of invisible but warming infra-red radiation. But you can see the effects of that radiation - think of the heat-shimmer you see over a tarmac road-surface on a hot sunny day.

A proportion of that radiation goes back up through the atmosphere and escapes to space. But another proportion of it is absorbed by greenhouse gas molecules, such as water vapour, carbon dioxide and methane.  Heating up themselves, those molecules then re-emit that heat energy in all directions including downwards. Due to the greenhouse effect, the total loss of that outgoing radiation is avoided and the cooling of Earth's surface is thereby inhibited. Without that extra blanket, Earth's average temperature would be more than thirty degrees Celsius cooler than is currently the case.

That's all in accordance with the laws of Thermodynamics. The First Law of Thermodynamics states that the total energy of an isolated system is constant - while energy can be transformed from one form to another it can be neither created nor destroyed. The Second Law does not state that the only flow of energy is from hot to cold - but instead that the net sum of the energy flows will be from hot to cold. That qualifier term, 'net', is the important one here. The Earth alone is not a "closed system", but is part of a constant, net energy flow from the Sun, to Earth and back out to space. Greenhouse gases simply inhibit part of that net flow, by returning some of the outgoing energy back towards Earth's surface.

The myth that the greenhouse effect is contrary to the second law of thermodynamics is mostly based on a very long 2009 paper by two German scientists (not climate scientists), Gerlich and Tscheuschner (G&T). In its title, the paper claimed to take down the theory that heat being trapped by our atmosphere keeps us warm. That's a huge claim to make – akin to stating there is no gravity.

The G&T paper has been the subject of many detailed rebuttals over the years since its publication. That's because one thing that makes the scientific community sit up and take notice is when something making big claims is published but which is so blatantly incorrect. To fully deal with every mistake contained in the paper, this rebuttal would have to be thousands of words long. A shorter riposte, posted in a discussion on the topic at the Quora website, was as follows: “...I might add that if G&T were correct they used dozens of rambling pages to prove that blankets can’t keep you warm at night."

If the Second Law of Thermodynamics is true - something we can safely assume – then, “blankets can’t keep you warm at night”, must be false. And - as you'll know from your own experiences - that is of course the case!

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!


Further details

Among the junk-science themes promoted by climate science deniers is the claim that the explanation for global warming contradicts the second law of thermodynamics. Does it? Of course not (Halpern et al. 2010), but let's explore. Firstly, we need to know how thermal energy transfer works with particular regard to Earth's atmosphere. Then, we need to know what the second law of thermodynamics is, and how it applies to global warming.

Thermal energy is transferred through systems in five main ways: conduction, convection, advection, latent heat and, last but not least, radiation. We'll take them one by one.

Conduction is important in some solids – think of how a cold metal spoon placed in a pot of boiling water can become too hot to touch. In many fluids and gases, conduction is much less important. There are a few exceptions, such as mercury, a metal whose melting point is so low it exists as a liquid above -38 degrees Celsius, making it a handy temperature-marker in thermometers. But air's thermal conductivity is so low we can more or less count it out from this discussion.

Convection

Convection

Figure 1: Severe thunderstorm developing over the Welsh countryside one evening in August 2020. This excellent example of convection had strong enough updraughts to produce hail up to 2.5 cm in diameter. (Source: John Mason)

Hot air rises – that's why hot air balloons work, because warm air is less dense than its colder surroundings, making the artificially heated air in the balloon more buoyant and thereby creating a convective current. The same principle applies in nature: convection is the upward transfer of heat in a fluid or a gas. 

Convection is highly important in Earth's atmosphere and especially in its lower part, where most of our weather goes on. On a nice day, convection may be noticed as birds soar and spiral upwards on thermals, gaining height with the help of that rising warm air-current. On other days, mass-ascent of warm, moist air can result in any type of convective weather from showers to severe thunderstorms with their attendant hazards. In the most extreme examples like supercells, that convective ascent or updraught can reach speeds getting on for a hundred miles per hour. Such powerful convective currents can keep hailstones held high in the storm-cloud for long enough to grow to golfball size or larger.

Advection

Advection is the quasi-horizontal transport of a fluid or gas with its attendant properties. Here are a couple of examples. In the Northern Hemisphere, southerly winds bring mild to warm air from the tropics northwards. During the rapid transition from a cold spell to a warm southerly over Europe in early December 2022, the temperatures over parts of the UK leapt from around -10C to +14C in one weekend, due to warm air advection. Advection can also lead to certain specific phenomena such as sea-fogs – when warm air inland is transported over the surrounding cold seas, causing rapid condensation of water vapour near the air-sea interface.

Advection

Figure 2: Advection fog completely obscures Cardigan Bay, off the west coast of Wales, on an April afternoon in 2015, Air warmed over the land was advected seawards, where its moisture promptly condensed over the much colder sea surface.

Latent heat

Latent heat is the thermal energy released or absorbed during a substance's transition from solid to liquid, liquid to vapour or vice-versa. To fuse, or melt, a solid or to boil a liquid, it is necessary to add thermal energy to a system, whereas when a vapour condenses or a liquid freezes, energy is released. The amount of energy involved varies from one substance to another: to melt iron you need a furnace but with an ice cube you only need to leave it at room-temperature for a while. Such variations from one substance to another are expressed as specific latent heats of fusion or vapourisation, measured in amount of energy (KiloJoules) per kilogram. In the case of Earth's atmosphere, the only substance of major importance with regard to latent heat is water, because at the range of temperatures present, it's the only component that is both abundant and constantly transitioning between solid, liquid and vapour phases.

Radiation

Radiation is the transfer of energy as electromagnetic rays, emitted by any heated surface. Electromagnetic radiation runs from long-wave - radio waves, microwaves, infra-red (IR), through the visible-light spectrum, down to short-wave – ultra-violet (UV), x-rays and gamma-rays. Although you cannot see IR radiation, you can feel it warming you when you sit by a fire. Indeed, the visible part of the spectrum used to be called “luminous heat” and the invisible IR radiation “non-luminous heat”, back in the 1800s when such things were slowly being figured-out.

Sunshine is an example of radiation. Unlike conduction and convection, radiation has the distinction of being able to travel from its source straight through the vacuum of space. Thus, Solar radiation travels through that vacuum for some 150 million kilometres, to reach our planet at a near-constant rate. Some Solar radiation, especially short-wave UV light, is absorbed by our atmosphere. Some is reflected straight back to space by cloud-tops. The rest makes it all the way down to the ground, where it is reflected from lighter surfaces or absorbed by darker ones. That's why black tarmac road surfaces can heat up until they melt on a bright summer's day.

Radiation

Figure 3: Heat haze above a warmed road-surface, Lincoln Way in San Francisco, California. May 2007. Image: Wikimedia Commons.

Energy balance

What has all of the above got to do with global warming? Well, through its radiation-flux, the Sun heats the atmosphere, the surfaces of land and oceans. The surfaces heated by solar radiation in turn emit infrared radiation, some of which can escape directly into space, but some of which is absorbed by the greenhouse gases in the atmosphere, mostly carbon dioxide, water vapour, and methane. Greenhouse gases not only slow down the loss of energy from the surface, but also re-radiate that energy, some of which is directed back down towards the surface, increasing the surface temperature and increasing how much energy is radiated from the surface. Overall, this process leads to a state where the surface is warmer than it would be in the absence of an atmosphere with greenhouse gases. On average, the amount of energy radiated back into space matches the amount of energy being received from the Sun, but there's a slight imbalance that we'll come to.

If this system was severely out of balance either way, the planet would have either frozen or overheated millions of years ago. Instead the planet's climate is (or at least was) stable, broadly speaking. Its temperatures generally stay within bounds that allow life to thrive. It's all about energy balance. Figure 4 shows the numbers.

Energy Budget AR6 WGI Figure 7_2

Figure 4: Schematic representation of the global mean energy budget of the Earth (upper panel), and its equivalent without considerations of cloud effects (lower panel). Numbers indicate best estimates for the magnitudes of the globally averaged energy balance components in W m–2 together with their uncertainty ranges in parentheses (5–95% confidence range), representing climate conditions at the beginning of the 21st century. Figure adapted for IPCC AR6 WG1 Chapter 7, from Wild et al. (2015).

While the flow in and out of our atmosphere from or to space is essentially the same, the atmosphere is inhibiting the cooling of the Earth, storing that energy mostly near its surface. If it were simply a case of sunshine straight in, infra-red straight back out, which would occur if the atmosphere was transparent to infra-red (it isn't) – or indeed if there was no atmosphere, Earth would have a similar temperature-range to the essentially airless Moon. On the Lunar equator, daytime heating can raise the temperature to a searing 120OC, but unimpeded radiative cooling means that at night, it gets down to around -130OC. No atmosphere as such, no greenhouse effect.

Clearly, the concentrations of greenhouse gases determine their energy storage capacity and therefore the greenhouse effect's strength. This is particularly the case for those gases that are non-condensing at atmospheric temperatures. Of those non-condensing gases, carbon dioxide is the most important. Because it only exists as vapour, the main way it is removed is as a weak solution of carbonic acid in rainwater – indeed the old name for carbon dioxide was 'carbonic acid gas'. That means once it's up there, it has a long 'atmospheric residency', meaning it takes a long time to be removed. 

Earth’s temperature can be stable over long periods of time, but to make that possible, incoming energy and outgoing energy have to be exactly the same, in a state of balance known as ‘radiative equilibrium’. That equilibrium can be disturbed by changing the forcing caused by any components of the system. Thus, for example, as the concentration of carbon dioxide has fluctuated over geological time, mostly on gradual time-scales but in some cases abruptly, so has the planet's energy storage capacity. Such fluctuations have in turn determined Earth's climate state, Hothouse or Icehouse – the latter defined as having Polar ice-caps present, of whatever size. Currently, Earth’s energy budget imbalance averages out at just under +1 watt per square metre - that’s global warming. 

That's all in accordance with the laws of Thermodynamics. The First Law of Thermodynamics states that the total energy of an isolated system is constant - while energy can be transformed from one component to another it can be neither created nor destroyed. Self-evidently, the "isolated" part of the law must require that the sun and the cosmos be included. They are both components of the system: without the Sun as the prime energy generator, Earth would be frozen and lifeless; with the Sun but without Earth's emitted energy dispersing out into space, the planet would cook, Just thinking about Earth's surface and atmosphere in isolation is to ignore two of this system's most important components.

The Second Law of Thermodynamics does not state that the only flow of energy is from hot to cold - but instead that the net sum of the energy flows will be from hot to cold. To reiterate, the qualifier term, 'net', is the important one here. In the case of the Earth-Sun system, it is again necessary to consider all of the components and their interactions: the sunshine, the warmed surface giving off IR radiation into the cooler atmosphere, the greenhouse gases re-emitting that radiation in all directions and finally the radiation emitted from the top of our atmosphere, to disperse out into the cold depths of space. That energy is not destroyed – it just disperses in all directions into the cold vastness out there. Some of it even heads towards the Sun too - since infra-red radiation has no way of determining that it is heading towards a much hotter body than the Earth,

Earth’s energy budget makes sure that all portions of the system are accounted for and this is routinely done in climate models. No violations exist. Greenhouse gases return some of the energy back towards Earth's surface but the net flow is still out into space. John Tyndall, in a lecture to the Royal Institution in 1859, recognised this. He said:

Tyndall 1859

As long as carbon emissions continue to rise, so will that planetary energy imbalance. Therefore, the only way to take the situation back towards stability is to reduce those emissions.


Update June 2023:

For additional links to relevant blog posts, please look at the "Further Reading" box, below.

Last updated on 29 June 2023 by John Mason. View Archives

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Comments 1051 to 1075 out of 1588:

  1. Fairly clear evidence that RW1 is trolling rather than debating: Me @1048:
    "The difference is 1.2 rather than 0.9, but Trenberth et al use 0.9 because: a) The difference between 1.2 and 0.9 is well within experimental error; b) The TOA balance has smaller experimental errors (+/-3% for individual components), and hence is considered more accurate than the surface balance (+/-5% for individual components except for Surface Radiation and Back Radiation which are +/-10%); and because c) If the surface was absorbing 0.3 Watts/m^2 more than was the planet (TOA) over a five year period, the excess energy would need to come from the atmosphere, plummeting atmospheric temperatures by about 24 degrees C over that period, whereas atmospheric temperatures increased over that period."
    RW1 @1050:
    "how is it that the 'NET Down" in the surface components table 2b and the TOA components table 2a is exactly the same (0.9 W/m^2?)? Are you saying that 'Net Down' means something different in each table?"
    So, in the post to which RW1 is responding I indicate that Trenberth et al use the Net Down calculated from the TOA at the surface rather than that calculated at the surface. I give sound reasons for that decision. In response RW1 accuses me of saying the Net Down means something different for the TOA and Surface tables, and suggests the identity of the values is unexplained. Either RW1 is deliberately misrepresenting the content of my (and e, and Sphaerica, and whoever else has been mad enough to try and clear up his "confusion" in this 1050 post thread) and of Trenberth et al; or he is terminally stupid; or he simply does not bother reading the responses in any event. All of RW1s confusions have been cleared up multiple times before, including by myself in the last 24 hours. If he really wants to understand, he can reread those posts and try to understand them.
    Response:

    [DB] When dealing with RW1, remember his own words:

    "I appreciate that you seem to be interested in helping me, but I'm not really interested in being helped per say. I'm a staunch skeptic of AGW, so my purpose here is to present contradictory evidence and logic that disputes the theory. That's what I'm doing."

    We deal with a closed-minded individual who is here for the sole purpose of wasting as much of as many people's time as possible.

    Solution

    Ignore him.  DNFTT.

  2. RW1@everywhere Are you trying to learn about a subject you do not understand or do you think you understand it better than anyone else?
  3. Tom Curtis (RE: 1051), "In response RW1 accuses me of saying the Net Down means something different for the TOA and Surface tables, and suggests the identity of the values is unexplained." I'm not accusing, just asking for clarification because I'm not sure I understand what you're saying. If you agree that "NET Down" means the same thing in both tables, why not just acknowledge it? I specifically asked about the data in the table of 0.9 W/m^2, not the 0.3 W/m^2 discrepancy relative to the numbers in the diagram, which I am aware of. I'll ask one more time. What does "NET Down" mean in tables 2a and 2b? If they mean the same thing, there is only one possible answer.
  4. pbjamm (RE: 1052), "Are you trying to learn about a subject you do not understand or do you think you understand it better than anyone else?" I admit I'm not here specifically to 'learn' per say, but I am fully capable of changing my mind on things when evidence dictates. I even changed my mind on something here due to evidence presented by Tom Curtis in regards to insolation in the Artic. I couldn't deny the evidence he presented to the contrary and acknowledged I was wrong. It is my view that the overwhelming majority of people at this site do not understand the information in tables and diagram from Trenberth's 2009 paper, nor do they understand the constraints COE puts on the boundary between the surface and the TOA, so I'm presenting evidence and logic in support of these things. Everyone here is free to make up their own mind, of course. If Tom does not want to continue this discussion - that's fine with me, but I can't help but to interpret his self removal as defeat. But again, everyone should make up their own mind.
  5. RW1 - "If Tom does not want to continue this discussion - that's fine with me, but I can't help but to interpret his self removal as defeat." Actually, if Tom decides he doesn't want to continue the discussion with you, I would congratulate him. You have consistently and repeatedly dismissed/ignored proven physics, cycled over and over on ideas that have been notably contradicted by actual measurements, and stated that: "...I'm not really interested in being helped per say. I'm a staunch skeptic of AGW, so my purpose here is to present contradictory evidence and logic that disputes the theory. That's what I'm doing." In my eyes, RW1, that makes you a troll, not someone actually interested in the science. Your arguments (and conclusions) are driven by your position, which is exactly backwards from how the scientific method works. And your comments on these posts illustrate that clearly to the unbiased reader - a self correcting issue. Folks, DNFTT.
  6. Tom Curtis (RE: 1048, 1050), ""The difference is 1.2 rather than 0.9, but Trenberth et al use 0.9 because: a) The difference between 1.2 and 0.9 is well within experimental error;" So what you're saying is Trenberth lists 0.9 as the "NET Down" in table 2b because it's arbitrarily within 'experimental error' of 1.2 W/m^2 and not because it means the same thing as "NET Down" in table 2a? OK, I'm perfectly willing to let this stand against what I've presented and everyone can make up their own mind.
  7. RW1,
    It is my view that the overwhelming majority of people at this site do not understand the information in tables and diagram from Trenberth's 2009 paper, nor do they understand the constraints COE puts on the boundary between the surface and the TOA, so I'm presenting evidence and logic in support of these things.
    Here's a homework assignment for you to work out entirely on your own, without assistance. This is a fairly simple assignment. I'm pretty sure just about everyone in my town middle school (6th to 8th grade) could get it right. The Trenberth energy budget has three layers: space, atmosphere, ground. It has 6 distinct paths of energy flow; space/sun to atmosphere, space/sun to ground, atmosphere to space, atmosphere to ground, ground to atmosphere, and ground to space. Please identify the components and individual and sum values for each of these elements (meaning in/out for each layer [3 pairs of values, in and out], and in/out for each interface between layers [6 pairs of values, in and out] ), identify which balance, and where you would expect the system, based on these numbers, to get out of balance. This is not a post that requires any response other than the answers. Until you arrive at these answers on your own, no one has any reason to listen or respond to you.
  8. Sphaerica (RE: 1059), I don't understand the assignment as you've laid it out. Thanks for the interest though.
  9. RW1@1054: "I admit I'm not here specifically to 'learn' per say..." And that about says it all wrt you. " If Tom does not want to continue this discussion - that's fine with me, but I can't help but to interpret his self removal as defeat." Yes, much like refusing to engage the raving derelict on the street corner is an admission of defeat and that his conspiracy is Truth.
  10. 1058, RW1,
    sun (A)<-6---1->atmosphere (B)<-5---2->surface (C)
    <-4-------------------------------------3->
    3 layers: sun/space (A), atmosphere (B), surface (C) 6 paths: sun to atmosphere (1), atmosphere to surface (2), sun directly to surface (3), surface directly to space (4), surface to atmosphere (5) and atmosphere to space (6). For each path (1, 2, 3, 4, 5, 6) identify the total energy flow, and list the contributing components and values (e.g. "thermals, 17"). For each layer (A, B, C) identify to the total in and out in each direction (up, down), as well as the total in/out for the layer, and the net (i.e. in minus out). For extra credit, identify the separate amounts of energy absorbed, reflected, and emitted by each layer. When you have worked through these numbers, and can see that everything balances and why, then you will be ready to actually start discussing any meaning behind the numbers and how they were determined.
  11. Sphaerica (RE: 1060), Even if I or anyone else could actually determine all these numbers (virtually impossible), what would be the point of any such exercise? To discover some new physical law? To discover that Conservation of Energy does not hold at the boundary between the surface and the TOA? If you're trying imply that all of these specific quantities need to be known in order to understand the contraints COE puts on the system, then I suggest you take some time to think about this a bit more. It's not that complicated.
  12. RW1 - I believe that Sphaerica is attempting to determine if you have actually understood the Trenberth diagrams. So far, it is not evident that you have. And hence (so far) your disagreements have not been particularly relevant, insofar as they have been understandable.
  13. KR (1062), I'm not saying the Trenberth diagram is entirely 'wrong' per say - it's just very misleading and has been largely misinterpreted by virtually everyone here. Let me ask you this, where in the diagram is the return path of latent heat in the form of precipitation? Surely, you agree evaporative latent heat of water and precipitation is a major surface -> atmosphere -> surface circulation current, right?
  14. 1061, RW1,
    Even if I or anyone else could actually determine all these numbers (virtually impossible)...
    It is more than possible, it's a trivial task. A twelve year old could do it. Tackle the assignment and see where it leads you. If you are not capable of doing the assignment, or choose not to, then you are clearly simply ignorant of the most basic aspects of Trenberth's diagrams, and communication with you is simply not possible. BIn taking that course, you would then abdicate any right whatsoever to offer any criticism or supposed insight on the subject. Why should anyone listen to you if you not only can't accomplish such a simple, five minute, analysis, but also think it is impossible? Gain some credibility. Perform the assigned task.
  15. 1063, RW1,
    ...where in the diagram is the return path of latent heat in the form of precipitation?
    Precipitation does not transport energy back to the surface. That only happens one way. Water vapor gains heat when evaporating at the surface, then releases that heat when condensing in the atmosphere. This moves the heat from the surface into the atmosphere, and that's all. It is clearly marked on the diagram as 80 W/m2 for "evapotranspiration" and "latent heat". There is no reverse mechanism. Do the assigned task. Until then you are complaining and criticizing without the most basic grasp of the diagram.
  16. 1063, RW1,
    it's just very misleading and has been largely misinterpreted by virtually everyone here.
    RW1, I'm sorry, but this is a laughable comment given how poorly you understand the diagram yourself. You are in no position to make such criticisms of others. Readers are asked to recognize this attitude on RW1's part, and take all of his comments with the grain of salt he has earned.
  17. Grain?
  18. The amount of energy coming into the ground is 184 watts from space(23 of which is reflected), and 333 watts from the atmosphere. The grand total of which is 517 watts. This is very close to the 516 watts being emitted from the ground through reflection (23), thermals (17), evapotranspiration (80) and surface radiation (396). The amount of energy coming into the atmosphere is 17 watts from thermals, 80 watts from evapotranspiration, 356 from surface radiation, 157 watts from space (79 of which is reflected). The grand total being 610 watts. This is very close to the 611 watts exiting through reflection (79), back radiation (333), and simply being emitted (199). The amount of energy coming into space is 102 watts through reflection (23 from the surface, 79 from the atmosphere), and 239 watts from outgoing longwave radiation (40 watts from the surface, 199 from the atmosphere). The grand total being 341 watts. This is the same amount of energy being released through incoming solar radiation. I'm 14.
  19. RW1@1063> Let me ask you this, where in the diagram is the return path of latent heat in the form of precipitation? Please read up on the basics of latent heat before commenting further. This is high school level material, until you understand it you cannot pretend to know what you're talking about. As Sphaerica described, latent heat is only released when a substance goes from vapor -> liquid or liquid -> solid. Since water vapor condenses in the atmosphere, it cannot release that same energy back to the ground as it is already a liquid. The "thermals" portion of Trenberth's diagram refers to sensible heat. In other words, it represents the conduction of heat from the warm water molecules into the cooler air molecules, resulting in the water molecules being cooled and the atmosphere heated. This will always be net positive from surface to atmosphere per the 2nd law of thermodynamics, since the atmosphere is cooler than the surface. The only mechanism by which cold falling rain can heat the warm surface is via the friction generated when the rain hits the ground and makes its way to the ocean. Is this the mechanism you are suggesting that negates energy transfer from latent heat? That would certainly be a "unique" claim.
  20. 1068, p. Curtis :D !!!! I was just going to scold you for giving RW1 the answers (don't you know that exchanging answers is academic misconduct?). Then I saw "I'm 14." Thank you. You made my day.
    Response:

    [DB] That one is precocious indeed.  I could not have done similarly at that age (but it was the mid-70s).

  21. RW1 - "Let me ask you this, where in the diagram is the return path of latent heat in the form of precipitation? Surely, you agree evaporative latent heat of water and precipitation is a major surface -> atmosphere -> surface circulation current, right?" You don't understand latent heat transport? The fact that it's one-way? I'm, well, I'm appalled. Learn some high-school physics before critiquing those who have spent their careers with this material. P. Curtis - My compliments. Folks whose ages are significant integer multiples of yours seem strangely unable to understand what you have done so clearly.
  22. Thanks for the compliments. I feel very happy that those of intelligent status think I am doing well :) Science is my greatest passion so it's always good to know I am succeeding in it.
    Response:

    [DB] Just keep working hard at it if that's what you enjoy.  The only thing separating you from anyone here is time and effort.  Good job!

  23. I don't want to revive a dead thread, but I've noticed that the responses on 2-nd law violation tend to be a bit um... dry. So I thought of an analogy that might...err resonate. Consider pushing a child in a swing. You aren't strong enough to push the swing very far in one push. But each cycle of the swing you can push a bit more and the higher the child goes. The kinetic energy of the swing can greatly exceed what you've put in in any one push. However, eventually you reach a point where the energy you put into the swing is completely dissipated on any cycle.... the swing goes no higher. This isn't obviously an exact analogy, but reason you can have larger values of back radiation and surface emitted radiation than TSI is somewhat analogous to pumping a swing. Whether this will help people caught up in inventing their own versions of the 2nd law I dont know.
  24. Will someone debunk this argument please? http://wattsupwiththat.com/2011/02/17/regarding-thermodynamics-and-heat-transfer-why-al-gore’s-comments-to-bill-o’reilly-at-fox-news-are-wrong/#more-34175
  25. Your claim that the greenhouse warming at the Earth's surface is 33K is plain wrong. This is because for an opaque [to IR] atmosphere, the -18°C equilibrium with space is in the upper atmosphere, about 5 km up. The surface temperature is then set by the rise in temperature from the lapse rate, c. 6.5K/km. So, the Earth's surface temperature is c. 33K higher than the upper atmosphere's radiative equilibrium 'temperature'**. If you take out the GHGs, the IR radiation from the Earth's surface is then not absorbed in the atmosphere, so it cools. However, your claim that the earth's surface would fall to -18°C is plain wrong because you still have the lapse rate, a consequence of gravitational potential energy. Because only a small proportion of heat is directly radiated from the Earth's surface, most is convected away and because the IR emissivity of N2/O2 is very low, that heat remains as sensible heat. The real GHG warming of the earth's surface is a bit less than 10K. If you still believe it's 33K then you have to go back to your basic education. **To calculate that you have to do a Hottel analysis. [-snipped-]

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