Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings


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.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Twitter Facebook YouTube Mastodon MeWe

RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

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

Printable Version  |  Offline PDF Version  |  Link to this page

Argument Feedback

Please use this form to let us know about suggested updates to this rebuttal.

Related Arguments

Further reading

References

Denial101x video

Comments

Prev  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  

Comments 426 to 426 out of 426:

  1. Finally damorbel came to the right point in his comment #424. He simply needs to add an heat source and he's done. I don't have much hope he'll do, though.
  2. damorbel wrote: "But the atmosphere is also between the Sun and the Earth, just like a blanket with a corpse underneath it is between the (ambient or Sun) heat source." However: (a) The atmosphere absorbs LW IR radiation but is essentially transparent to SW radiation (visible light and ultraviolet) (b) Most of the radiation given off by the Sun is SW radiation not IR. (c) Most of the radiation from the sun is not absorbed by the atmosphere [see (a)], so the Sun does not significantly heat the atmosphere directly. The atmosphere does not significantly insulate the surface from suns radiation. (d) When the surface absorbs most of the suns SW radiation, it heats up and re-radiates LW IR radiation upwards. (e) The atmosphere does absorb some of this outbound IR radiation, and hence it heats up. The atmosphere is not warmed directly by the sun, but indirectly by the IR radiated from the surface. (f) The atmosphere being warmer than space thus insulates the surface from space, causing it to be warmer than it would otherwise be. (g) This does not violate the second law of thermodynamics as the net transfer of heat is from the warmer surface to the cooler atmosphere. (h) The greenhouse effect thus does not violate the second law of thermodynamics, and Roy Spencer (amongst others is perfectly correct on this point and G&T are flat wrong). O.K., I've spelled it out for you. Which of these points do you disagree with? For the sake of clarity, it would be best if you could make a list (a)-(h), saying whether you agree with the point or not, and if not explaining why.
  3. 423 damorbel, You are obfuscating the same point I was trying to make to RW1. In one post he calls it "energy", in another, "power", in another "radiation". The point is a that an object of higher temperature can receive "energy, power or radiation", or what the hell ever you and RW1 want to call it when it is convenient for you, from a lesser temperature object because that higher temperature object cannot discriminate the source of the "energy, power, or radiation" it absorbs.
  4. Re #428 RickG you wrote:- "You are obfuscating the same point I was trying to make to RW1. In one post he calls it "energy", in another, "power", in another "radiation"" 'energy' is measured in Joules 'power' is measured in Watts (Joules per sec.) 'Radiation' is hvwhich is a form of energy dependent on the source frequency 'v'. If you don't get these right then you will become hopelessly confused. Perhaps RW1 didn't get it right, one has to be careful.
  5. damorbel - If the sun heated the Earth via heating the atmosphere (which seems to be what you are arguing), the lapse rate would be reversed and there would be essentially no convection. This is not the case. Sunlight passes through the atmosphere, heats the Earth just as the heater coil in my example did. "If you blocked the Sun off (and you can) the Earth would cool. This is because the Sun is external to the Earth and its atmosphere." - This is a complete red herring. You could turn the heater coil on the block off and on again - it doesn't change the physics of heat transfer. Claiming that is quite the horrid dodge, damorbel - you're really straining there, and I find it appalling. You've painted your argument into a corner. Energy goes from the Sun -> Earth -> Atmosphere -> Space, with the atmosphere acting as an insulator. --- Everyone, this has been quite a discussion. >400 posts on the greenhouse effect, many of which have done a good job looking at the physics. Unfortunately, damorbel, you seem willing to go to extremes to deny the radiative greenhouse effect, including that silly bit about 'turning the sun on and off' to attempt to disprove the fact that the atmosphere is heated by the Earth's surface. At this point I have to consider you to be either (a) a troll, stretching this out to claim controversy on the topic, or (b) fanatically unwilling to listen to reason and abandon your incorrect ideas on thermodynamics. Either way, damorbel, you are no longer worth my time. I believe the current thread has plenty of information for newcomers, who can clearly judge the topic (and posters) based upon what they read. I'm done here.
    Response: [muoncounter] KR should be commended for showing terrific patience in going this far. [DB] Seconded. I would add that I found myself learning the subject even more thoroughly as a result, so in that regard it was time not wasted.
  6. @muoncounter Not only should st. KR be commended, he should be canonised - he clearly has the patience of a saint, so he should get the honorific as well ;o) In discussions of climate, again and again we see evasion, pedantry a refusal to stick with thought experiments intended to clarify matters and a refusal to give a direct answer to a direct question (which risks giving a hostage to fortune - but those only interested in the truth are not bothered by that). The, best approach to dealing with this seems tireless patience; it is quickly evident who is there to discuss the science, but it shouldn't really be necessary.
    Response: [muoncounter] Agreed: St. KR it is. Forgive me if I omitted thanking anyone who has stayed with this for the long haul; haste causes carelessness. It is a shame when a thread becomes so long and convoluted that contributing posters finally say 'enough.'
  7. I agree with muoncounter's moderator response above, but would also add commendations to Dikran Marsupial and les - as well as several others who tried their best to impart their knowledge. I certainly found it very educational, if only because you all had to go round and round repeating the same facts again and again, hoping it would all sink in eventually ! It worked with me, anyway... (Strange how none of the self-appointed expert so-called skeptics got inolved, though. No, actually, it's not strange at all, is it ?)
  8. Re: JMurphy (432) Indeed. One was left with the sound of one hand clapping... The Yooper
  9. I've actually found most of the misunderstandings of the greenhouse effect and the 2nd law of thermodynamics are intimately tied to the Fallacy of Division: that what is true of the whole is true of the constituents. "4 is even. 1 and 3 are part of 4, so they must be even too!" Each individual energy transfer - collision, molecular diffusion, photon absorption/emission - can occur in any direction. From a cold nebula to a star, from a candle to a plasma torch, from your hand to the boiling pot you mistakenly grabbed. It's only statistically, in the aggregate, that "Heat" transfer shows up, as the higher energy moves to the lower, based on the fact that there are many more energy transfer events going in that direction. The 2nd law of thermodynamics, and entropy, is a statistical law, a law of summations, not a factor in individual molecular events. It does not, can not, block energy from moving between a cold object and a warm object, adding to its energy. It's just that statistics indicate a greater number going the other way - and with molecular numbers statistics are pretty much a dead certainty. This fallacy is never more clear than with the "colder objects can't heat warmer ones", where I've seen attempted justifications such as "warm objects won't absorb low energy photons!", "destructive interference of cold photons with warm ones keeps them away", and my favorite "They just know, and the warm object doesn't accept them!" When faced with such "logic", it's a tossup whether to laugh, cry, or fetch a strong beer... --- I have to compliment fellow posters for their patience too - Dikran, les, muoncounter, everyone else. I find this website a fantastic forum for civilized discussion; I cannot think of another place where this wouldn't have degenerated into poorly written invective a long time ago.
  10. Re #427 Dikran Marsupial I agree (a)->(e) But then you wrote:- "(f) The atmosphere being warmer than space thus insulates the surface from space, causing it to be warmer than it would otherwise be." Insulate is not really the right word for the atmosphere. The gases of the atmosphere are free to mix and flow, convection is happening all the time, none of these produce the effects of an insulator. "g) This does not violate the second law of thermodynamics as the net transfer of heat is from the warmer surface to the cooler atmosphere." Couldn't agree more! "(h) The greenhouse effect thus does not violate the second law of thermodynamics, and Roy Spencer (amongst others is perfectly correct on this point and G&T are flat wrong)." I'd like to know how you think the GHE effect works. 2nd law of thermodynamics states that energy does not transfer spontaneously from a cold place to a hotter. For example, can energy transfer from a place at 0K to a place at 50K? If this were true I suggest that energy might indeed transfer spontaneously (in the atmosphere) from 250K to 300K but I don't see it happening somehow.
  11. Re #434 KR you wrote:- "It does not, can not, block energy from moving between a cold object and a warm object," My question is, can the "energy [from] moving between a cold object and a warm object" raise the temperature of the warm object, as described in the GHE? If so how do you calculate it?
  12. Damorbel, The energy from the cold atmosphere is not enough to "raise the temperature" of the warmer Earth. It keeps the Earth from cooling as fast as it used to. The input energy from the sun stays the same. Since the input energy stays the same and the Earth cools slower the equilibrium temperature of the Earth goes up. The net energy flow is from the warm Earth to the cold atmosphere (as required by the second law), but the greenhouse gasses slow the cooling energy transfer. Standing on the Earth surface slower cooling with the same input energy means hotter. The GHE is not to move net energy from the cold atmosphere to the warm Earth. The GHE slows the rate at which the Earth loses heat to space.
  13. damorbel re. (f) you are quibbling about the meaning of words again, rather than addressing the fundamental point. Convection and conduction cause a transfer of heat energy from the near surface to the upper atmosphere, but heat energy can only be lost to space through radiation from the upper atmosphere. Hence the atmosphere as a whole acts as an insulator. Do you agree with the fundamental point that the atmosphere being warmer than outer space means that the surface looses heat energy to space more slowly than it would if the atmosphere were not there? Please can you give an answer to h, I have already explained the basics of how the GHE works in (a)-(f). The only bit I have left out is exactly how the equilibrium temperature is determined, which is not required to refute the assertion that the GHE violates the second law of thermodynamics. If you want clarification of a particular point (a)-(f), then ask specifically. Do you agree that the atmosphere impedes energy, in the form of LW IR, being radiated from the surface from reaching space, but does not substantially impede the SW radiation from the sun reaching the Earth's surface? As to your last point. Consider two black-body objects, A and B placed close to eachother in a vacuum at 0K. Both are fractionally above absolute zero, such that the rate at which they randomly emit photons is very low, but body B is fractionally warmer than body A. We observe both bodies for a period of time that is about the same as the period between IR photons being emmitted by the cooler body. Now in some of those periods of observation, a photon will have been emitted by body B and will be absorbed by body A, making it slightly warmer. In a smaller proportion of observation intervals, a photon will be emitted by object A and absorbed by object B. In that case there has been a transfer of energy from a cooler object to a warmer object. This doesn't violate the second law of thermodynamics however, as on average there will be more intervals where the photon went from warmer to cooler than from cooler to warmer, as the warmer object will be emitting more photons.
  14. Re #438 michael sweet you wrote:- "The energy from the cold atmosphere is not enough to "raise the temperature" of the warmer Earth." But the IPCC says GHE is warming the Planet by 33C - up from 254K to 288K. That is not just a little bit, it's a whacking great amount. Also you wrote:- "It keeps the Earth from cooling as fast as it used to." But radiation from water and CO2 is the way the atmosphere loses heat to deep space. GHE theory says 'more CO2 absorbs more heat' (I thoroughly agree) But doesn't 'more CO2' also radiate more heat into deep space? Seems to me 'AGW due to CO2' has no validity.
  15. damorbel: Seems to me 'AGW due to CO2' has no validity. Then to what do you attribute AGW?
  16. Re #438 Dikran Marsupial you wrote:- "Do you agree with the fundamental point that the atmosphere being warmer than outer space means that the surface looses heat energy to space more slowly than it would if the atmosphere were not there?" Like I said to Mike Sweet, more CO2 in the atmosphere means the atmosphere become a more powerful radiator of heat, don't you agree?
  17. damorbel I see you have gone back to refusing to answer direct questions again and instead are opting for evasion instead. "Like I said to Mike Sweet, more CO2 in the atmosphere means the atmosphere become a more powerful radiator of heat, don't you agree?" Even though your question is evasion, to avoid answering my question, I'll answer it anyway. No, I don't agree. The more CO2 in the atmosphere, the higher in the atmosphere IR has to be emitted before it isn't absorbed by CO2 in the layers above. The lapse rate means this layer will be colder, and hence the less radiation that is emitted and so the atmosphere below and hence the surface will become warmer. If you were familiar with the basic mechanism of the GHE you would know that.
  18. Re #440 RickG you wrote:- "Then to what do you attribute AGW?" I am much happier with 'Climate Change' or even better 'Climate Variability' Most of the Sun's heat comes in at the tropics, the atmosphere and the oceans spread this over the globe by various currents that do not follow stable routes; the re is a great tendency to turbulence in fluid flow, even on a global scale. The most obvious example of this is the El Nino current which is highly unstable but there are many, many other currents all of which have powerful heat carrying capacities. Monitoring current flows would go a little way to explaining climate changes. Also Svensmark's cloud generating cosmic rays would have a powerful effect on heat transport in the atmosphere, quite enough to explain ice ages.
  19. Re #442 Dikran Marsupial you wrote:- "If you were familiar with the basic mechanism of the GHE you would know that" I am familiar with a variety of GHE explanations including the "higher altitude radiation" one you cite which is quite different from the "backradiation" one; the one that busts the 2nd law of thermodynamics. None of these AGW - CO2 models stand up to serious examination. But I agree that there are rather too many understandings of how thermodynamics works; even simple matters like the definition of temperature are wildly misunderstood and wrongly taught, particularly at universities.
  20. damorbel The "higher altitude radiation" and "backradiation" are both parts of the same theory (neither violate the second law of thermodynamics). Again you are demonstrating that you do not understand the mechanism of the greenhouse effect. I'm also not going to get drawn into a discussion of the definition of temperature, that is just another attempt at to derail the discussion. You are still avoiding answering the questions I posed in earlier posts.
  21. I think I should have stayed out of this conversation, but I will answer your direct question. More CO2 does not mean more radiation into space. The increase in CO2 raises the level in the atmosphere where radiation escapes into space (see post 442 above). Since it is colder higher in the atmosphere less radiation is emitted into space and the planet warms. You are defining what is "warming" and what is "heat transfer" incorrectly. CO2 warms the lower atmosphere by reducing heat loss. This is consistant with the second law. The IPCC says the greenhouse effect "warms" the lower atmosphere 33C by reducing heat loss to space. The CO2 does not contribute energy to the system. My blanket warms me 10-15C every night by reducing heat loss from my body to my room. Where is the problem? I will leave this to the others who are trying to explain it to you, I don't think I have anything to add that they have not said before.
  22. damorbel: "Svensmark's cloud generating cosmic rays" Wow, you think that thermodynamics is 'wildly misunderstood,' but you accept Svensmark as a 'powerful effect'? The GCR->clouds->cooling idea fails rigorous scrutiny; even the CERN CLOUD experiment, tailor made by Kirksby to test the idea, is producing "underwhelming" results. See Its cosmic rays. Are we on ABC territory here? Anything but CO2?
  23. I'm still waiting to see whether damobel would change his mind if an experiment showed a result that was incompatible with his application of 2nd Law (and compatiable with standard radiative physics textbooks).
  24. Folks - we've now had 'natural cycles', 'cosmic rays', 'heat of compression', 'it's the sun' and 'thermodynamics and temperature are poorly defined'. And that's just in the last three days. Before that there was 'albedo', multi-layer insulation, 'sunlight can't make it out of the water', 'constant disequilibrium', 'elastic collision of photons', and the lovely bit of obfuscation, "All materials, even gases, have a refractive index >1, consequently no material substance can behave according to the definition of a black body". And without really defending any one position - just moving to the next whenever getting nailed down in contradictions - not the behavior of someone who actually deeply believed anything they were stating. damorbel is, I believe, a troll. His sole purpose here appears to avoid any answers or conclusions, rather than to reach one. I suggest we not feed the troll...
  25. @449, Agreed, especially with your last comment.

Prev  1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  

Post a Comment

Political, off-topic or ad hominem comments will be deleted. Comments Policy...

You need to be logged in to post a comment. Login via the left margin or if you're new, register here.

Link to this page



The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2023 John Cook
Home | Translations | About Us | Privacy | Contact Us