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Greenhouse warming 100 times greater than waste heat

What the science says...

Select a level... Basic Intermediate

Greenhouse warming is adding 100 times more heat to the climate than waste heat.

Climate Myth...

It's waste heat

"Global warming is mostly due to heat production by human industry since the 1800s, from nuclear power and fossil fuels, better termed hydrocarbons, – coal, oil, natural gas. Greenhouse gases such as carbon dioxide (CO2 play a minor role even though they are widely claimed the cause." (Morton Skorodin)

At a glance

There are various kinds of climate science deniers out there, but one grouping can usefully be classified under the acronym ABCD - Anything But Carbon Dioxide. These people appear to accept the climate is heating up. Flailing around to try and identify something other than CO2 causing the heating, they will seize upon all sorts of candidate causes. This is one of them. There are many others.

All the energy we use dissipates into the environment post-use, be it a driftwood fire on the beach or the heart of a busy metropolis, on the go 24-7. So it should come as no surprise that 'waste' heat does have a role - a minor one - in heating the planet. Humans have always been fond of fire since they learned to ignite things and there's nothing better than sitting round a blaze of a night with a few friends. No need to feel guilty about that. It's harmless in the overall scheme of things.

Waste heat is of course a much studied subject. After all, more sophisticated heating systems, compared to that fire on the beach, are energy-intensive and that translates as expensive. Ways to minimise heat loss and thereby improve efficiency form an active research topic. In that sense, a number of studies have looked at the bigger picture: just how much waste heat is there?

Unsurprisingly, cities, where huge numbers of people work, rest and play, are megacentres of heat wastage. The term, 'Urban Heat Island', acknowledges this. But the planet is a big old place and cities occupy relatively small parts of it. To find the warming contribution of waste heat, you need to have two figures: the total energy lost and the surface area of the planet. Doing the maths you can then derive the amount, expressed in watts per square metre. You can then compare it to other heat sources.

All studies of waste heat have arrived at a similar conclusion. There's a lot of waste heat over cities but the total, global amount, expressed as watts per square metre of the planetary surface, is a tiny fraction of the heating caused by the greenhouse gases. So while it's highly desirable to find better efficiencies in energy use and conservation, thereby saving money, when it comes to temperature it's greenhouse gas emissions we have to hold firmly in our focus. ABCD indeed. Next.

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

Heat is released to the atmosphere as a result of human activities, many of which involve combustion of fuels, directly or indirectly. Sources of this 'anthropogenic heat' include industrial plants, heating of buildings, air-conditioning, vehicle exhausts and many more. In cities, anthropogenic heat typically contributes 15–50 W/m2 to the local heat balance, and several hundred W/m2 can be reached in the centres of large cities in colder climates.

This heat doesn't just disappear - it dissipates into our environment. How much does waste heat contribute to global warming? There have been several studies over the years, widely-cited examples being Flanner (2009) (if you want to read the full paper, access details are posted here), Dong et al. (2017) and Varquez et al. (2021). All have come up with similar numbers despite differences in methodology: the core message is that while waste heat is an issue and is self-evidently undesirable, its contribution to global warming is a tiny fraction of that brought about by CO2.

Flanner concluded that the contribution of waste heat to the global climate was 0.028 W/m2. That was with respect to the mid 2000s. In contrast, the contribution from human-emitted greenhouse gases at the time was 2.9 W/m2 (fig. 1). So in the mid 2000s, waste heat amounted to about 1% of the total warming, with greenhouse gases making up much of the rest. The above numbers refer to radiative forcing, the change in energy flux at the top of the atmosphere. Or putting it in plain English, the amount of heat being added to our climate.

Relative radiative forcings due to waste heat and CO2.

Fig. 1: the relative radiative forcings due to waste heat and CO2 in the mid 2000s, from the numbers presented by Flanner (2009).

Since that time, both greenhouse gases and energy use have gone up (fig. 2), so it should come as no surprise to see increases in radiative forcing in both cases. Future projections have largely been focussed on recovery of the waste heat, such as that by Firth et al. (2019). An important conclusion of theirs is that, "full recovery of the theoretical potential is found to lead to a 10–12% reduction in the combined forcing of CO2 and waste heat over this period, mainly due to a reduction in CO2 emissions."

An important point to consider here is that the warming from thermal energy production occurs when a fossil fuel undergoes combustion. Whoomph! and that's that - the energy is produced in a single pulse then dissipates away. In contrast, warming from the emitted CO2 continues for the lifetime of CO2 in the atmosphere - potentially thousands of years (Zhang & Caldeira 2015). Zhang and Caldeira showed that "the energy released from the combustion of fossil fuels is now about 1.71% of the radiative forcing from CO2 that has accumulated in the atmosphere as a consequence of historical fossil fuel combustion." Again a small fraction of the CO2 radiative forcing, and emphasising the issue of the cumulative build-up of CO2 due to its relatively long atmospheric residence time.

Total energy use on Earth.

Fig. 2: total energy use on Earth, 1800-2023.

To conclude, greenhouse warming is currently adding some 60-100 times more heat to our climate than waste heat. That's not to say we should not be bothered about waste heat though, There are many sound reasons, including economic, for reducing heat wastage. It makes no sense at all to tolerate systems that for various reasons are grossly inefficient. But that needs to be considered as a separate entity from the huge problem of human CO2 emissions.

Last updated on 7 January 2024 by John Mason. View Archives

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Comments 151 to 175 out of 204:

  1. Despite lightning's insignificance as an escape mechanism for energy, Tom's back of the envelope calculation for energy lost from Earth due to lightning is still fascinating.

    One of the few consolations for ceasely stirring the AGW pot is seeing such interesting appreciations for the flow of eye-popping amounts of energy hither and thither.  Yes, lightning isn't a big loss contributor but still the amount of power there is awesome.

    Thanks, Tom.

  2. Can we recast these figures in watts?

    Talking about change since 1750...

    Waste heat would be 14E12 W (based on Flanner which does the full accounts)

    I can't see how lightning isnt accounted for TOA loss, but is 2E10 W (total rather than change)

    Since the top of atmosphere is cooling not heating due to increase in GHG, I cant see why losses from mass ejection would increase (OS thinks they would), but with an escape velocity of 10.8 km/s and about 3kg/s lost, total losses (not change since 1750) is of order E11 W

    Change in energy at surface however since 1750 dues to increase in GHG is

    1.4E15 W

    No way to avoid the conclusion that waste heat is insignificant by comparison.

  3. I have speculated about a number of ways in which the earth can dissipate energy apart from i/r emissions and no doubt they play a part - especially if things get violent. However the relative importance of waste heat is coming up the conscience scale as models are now beginning to refer to 'urban hotspots'.

    I think the following argument will show why waste heat is more important than the simplistic arguments which seek to dismiss it.

    You have to return to the fundamental physical - not organic -phenomena which makes the earth's response to variations in incident energy so robust.

    From afar, the earth is a spheroid which will see its surface temperature vary by 1 deg K (around 300 say) for every 1.35% change in solar energy - whether by orbit or output. So that degree of stability is pretty assured.

    Next, the difference between a cloud base at the bottom of the troposphere and top, ten miles, corresponds to a 0.5% change in the effective radiating surface area. It means that should the temperature rise by 1/3rd degree, it could be eliminated by increased radiation from elevated cloud cover.

    Despite argument to the contrary, it is a scientific fact that the major energy transfer agent from the surface is kinetic by gases.

    The physical mechanism for raising the emitting surface is that as water is the pervasive surface on earth, any general heating increases the water vapour content. Being lighter than all other gases (except Helium) it takes latent heat and acquired kinetic energy up to a point where it condenses into droplets. These radiate extremely efficiently so that a cloud effectively becomes the conversion mechanism for kinetic to radiant discharge. 

    The effective radiating surface is not just the radius effect. Each droplet radiates isotropically so do all those droplets within five characteristic absorption lengths of the surface adding to the output. The surface  also is lumpy with towering pillars of cloud. The mechanism deserves fuller treatment than I can cover here to show outbound exceeds downward but the net effect is to provide a temperature dependent height for a surface from which earth radiates.

    As CO2 is 2.5 times heavier than H2O, I doubt that there is a significant CO2 effect trapping heat above the topmost cloud cover.  I remain a sceptic over the overarching significance of CO2 when set against that of H2O.

    The upshot is that waste heat involves a huge lag between its generation and the  increase of H2O as required for temperature stability whereas all natural changes are immediate because the oceans are bathed by it. Waste heat is generated in concentrated areas over land and is different from the patterns which produce the jet stream and trade winds. That may have a greater impact on climate phenomena than anything. A mouse can upset a see saw balanced by two elephants.

    Of one thing I am sure, waste heat is not ignorable.


    [JH] Unneccesary white space eliminated.

  4. old sage - There are more errors in your posting than are worth the time to point out. I'll simply list a couple of them.

    "Despite argument to the contrary, it is a scientific fact that the major energy transfer agent from the surface is kinetic by gases." False. See for example the Trenberth 2009 energy budgets, which note that ~97 W/m2 transfer from surface to atmosphere via evaporation and thermals, while ~396 W/m2 by IR, or a 4:1 ratio. Your assertion is not even close to reality. 

    "As CO2 is 2.5 times heavier than H2O, I doubt that there is a significant CO2 effect trapping heat above the topmost cloud cover." Again, False. CO2 is a well-mixed gas, present throughout the atmosphere. And in fact it's primary effect as a GHG occurs above where water vapor does. If your statement were correct, valleys would be uninhabitable due to CO2 levels, which is clearly _not_ the case. 

    Your post consists of pseudoscientific Woo - I would suggest doing some reading. The Discovery of Global Warming by Spencer Weart would be an excellent starting point. 

  5. Old Sage, you still appear to be labouring under a misapprehension over the basic operation of the greenhouse effect, that I pointed out to you earlier in the thread here.

    You write "As CO2 is 2.5 times heavier than H2O, I doubt that there is a significant CO2 effect trapping heat above the topmost cloud cover."

    The greenhouse effect depends on the temperature of the radiating layer in the atmosphere where outbound IR is not absorbed by CO2 (or H2O).

    Note also that the atmosphere gets colder with height, which means that the atmosphere also gets drier with increasing altitude because the water vapour precipitates out. 

    "I remain a sceptic over the overarching significance of CO2 when set against that of H2O."

    Well perhaps you should have read the realclimate article that I mentioned in my previous reply to your earlier comments.

  6. old sage - I will also note that you are recycling much of the same nonsense you put forth earlier in the thread (here and subsequent discussion). Said assertions on your part were nonsense, and eventually moderated/snipped as sloganeering.

    You do not appear to have added any actual content to your arguments at the current time. 

  7. Old Sage @153:

    1) "...the earth is a spheroid which will see its surface temperature vary by 1 deg K (around 300 say) for every 1.35% change in solar energy..."

    A 1.35% alteration in the solar constant represents a 3.23 W/m^2 change in TOA forcing.  That means OS is assuming a no net feedback climate sensitivity, ie, a climate sensitivity equivalent to 1.15 C per doubling of CO2.  That figure disagrees with nearly all studies of the subject, and is almost certainly inconsistent with the past history of the Earth's temperature variation, as is shown by the IPCC AR5:

    2) "...the difference between a cloud base at the bottom of the troposphere and top, ten miles, corresponds to a 0.5% change in the effective radiating surface area..."

    The actual difference in area between sea level, and 10 km above sea level is 0.31%.  That is not a 0.5% change in the effective radiative surface as the effective altitude of radiation to space is already approximately 5 km of altitude, meaning shifting the effective radiation to space to 10 km would only increase the effective radiation surface by 0.16%.

    3)  "It means that should the temperature rise by 1/3rd degree, it could be eliminated by increased radiation from elevated cloud cover."

    This assumes 100% cloud cover.  It also assumes the increased effective area of the clouds will have no effect on albedo.  These, however, are trivial flaws by OS's standards.  The beggest flaw is that he ignores the fact that the atmosphere cools with increased altitude.  As IR radiation to space is proportional to the fourth power of temperature, that means increasing the altitude of effective radiation to space reduces the radiation to space (which is the essence of the greenhouse effect).  Assuming a reduction in temperature of 6.5 K per kilometer of altitude, and an average surface temperature of 288 K, and allowing for the change in surface area, increasing the effective altitude of radiation to space from 0 to 10 km would reduce radiation to space by 64%.  The reduction from increasing the current effective altitude of radiation to space to 10 km is reduces the radiation to space by 32%.  This would require a substantial increase in the Earth's surface temperature to compensate (significantly greater than 10 C).  (It should be noted that these figures are calculated using OS's black body assumption of all radiation coming from just one level, which is false.  Using a realistic model the reduction in IR radiation, and hence the compensating temperaure increase prior to feedbacks would be less.)   

    4) "... it is a scientific fact that the major energy transfer agent from the surface is kinetic by gases."

    In fact, within the troposphere the dominant form of energy transfer between atmospheric layers is by convection (ie, kinetic by gases).  Contrary to KR, Trenberth adresses the different issue of transfer of heat between the Earth's surface (ie, dirt and rock, or water) and the atmosphere.  So OS is correct on this one, but while correct he is irrelevant.  The only form of energy transfer from the surface or atmosphere to space is by IR radiation (ignoring a very small amount of energy carried of by hydrogen and helium escaping to space).  The kinetic transfer of energy in the atmosphere establishes a very clear gradient in temperature, which limits the IR radiation to space as the effective level of radiation to space is forced higher in the atmosphere by greenhouse gases.

    5)  "The physical mechanism for raising the emitting surface is that as water is the pervasive surface on earth ..."

    As a side note, we see here that OS assumes the WV feedback rases the effective level of radiation to space, with together with the declining temperature with altitude makes it a strongly positive feedback.  He is, of course, unaware of the implications because his grasp of the physics is so poor.

    More importantly, water vapour is IR active.  That is, it absorbs IR radiation in part of the spectrum in proportion to its emissivity, and emits in the same part of the spectrum in proportion to its emissivity, and as a function that increases with increasing temperature.  Thus implicit in OS's argument is the fact that increasing the concentration of any IR actively gas (eg, CO2) in the atmosphere will increase temperature.

    6) "As CO2 is 2.5 times heavier than H2O, I doubt that there is a significant CO2 effect trapping heat above the topmost cloud cover."

    OS "doubts", but in the mean time observations* show the following:

    Note that while water vapour declines in concentration rapidly, being almost completely absent above 10 km in the atmosphere, CO2 remains near constant in the atmosphere up to 80 km in altitude.  The decline in water vapour concentration is because it precipitates out of the increasingly cold atmosphere.  Even in the tropics, atmospheric temperatures fall below freezing around 5 km of altitude, so that apart from in thunderstorms, water vapour is largely absent above that altitude.

    Even better, we can see which has the most effect on IR radiation to space, as it has been observed from space:

    The black body curves show the average temperature of gas radiating at that level.  As can be seen in the clear sky example, water vapour (to the left of the large notch at 650 cm^-1) has a brightness temperature in this example, of about 260-270 K, indicating its effective altitude of radiation is 4.6 km.  The large notch, however, is due to CO2.  Its brightness temperature is around 225 K, indicating an effective altitude of radiation of 11 km.  The spike in the center of the trough is because where CO2 most effectively absorbs, its effective altitude of radiation is in the lower stratosphere, which is warmer than the upper troposphere.

    Of course, you cannot fail to have noted the spectrum for the thunderstorm anvil, with a brightness temperature of 210 K, and hence an approximate altitude of 13 km.  High altitude clouds are amazingly effective greenhouse agents, but only high altitude clouds can get above the warming effect of CO2; and they occupy only a small proportion of the Earth's surface.

    These two observed spectrums (and countless others like them) show clearly, and by observational data, that OS's doubts exist only from failure to look at the evidence.

    (*The graphs are for the US Standard Atmosphere which is a standard specification of average US atmospheric conditions, primarilly used in aviation.  It is based on very detailed observations, but only approximates to those observations.)

    7) "The upshot is that waste heat involves ..."

    OS continues his evidence free ramblings.  The facts are that waste heat is dissipated very rapidly to the rest of the Earth's surface by winds.  For small wheather effects, that dissipation may not be fast enough so that it has some effect.  For climate, however, the dissipation is sufficiently rapid that the feedbacks for waste heat occure at the same pace and geographic scale as the feedbacks from increased CO2 concentration.  Therefore there effective impact on the Earth's climate is given to a first approximation by the scale of their globally averaged output.  That is, waste heat has one hundredth of the impact of increased CO2.

    In summary, OS demonstrates yet again that he has no clue about the basic physics involved in climate change, and a very poor, and in most areas, non-existent grasp of the relevant observational evidence.  He never-the-less is "sage" enough to think he knows better than scientists who spend their life studying the subject, and have gone over the observations and basic physical principles with a fine tooth comb.  His "sagacity" is, therefore, the sagacity of the witch-doctor rather than the scientist.

  8. I am linking to my discussion about nuclear power from here

  9. The paper from Mark G. Flanner (2009) "Integrating anthropogenic heat flux with global climate models" arrives at the following numbers for:

    Global "waste heat" flux: 0.028 W/m2 in 2005 and 0.059 W/m2 in 2040

    Regional "waste heat flux": up to 0.68 W/m2 in 2005 and 0.89 W/m2 in 2040 (both numbers for West Europe).

    In a regional to local level both greenhouse and waste heat warming can be significant, approaching the current level of greenhouse forcing (3W/m2) in some areas (table 2).

    This result supports the earlier, coarser work of  Chaisson (2008)  , "Long-Term Global Heating from Energy Usage", that arrives at the conclusion that global warming from waste heat alone can warm the planet by 3°C in 8 doubling times of the global non-renewable energy consumption. At a 2% growth rate in energy consumption this would happen in 280 years and at 1% growth rate in 320 years.

    I see no loophole in this result, indicating that carbon neutrality is a necessary, but by no means sufficient, condition to prevent overheating a planet. In the longer term, net energy neutrality is also necessary.

    Renewable energy that takes energy already in the environment can do the trick, and there are lots of it. On the other hand, carbon-neutral non-renewable energy sources like nuclear or fossil fuels with carbon capture and storage do not.

  10. green tortoise @159, that is a very valid point, and also applies to fusion power (if and when it becomes viable).  However, it places a cap on fision and/or fusion power at approximately the total current human energy use, or there abouts.  If the deployment rates were favourable, we would do well to transfer all human power consumption to fision and/or fusion now, and restrict future energy growth to renewables.  Unfortunately the deployment rates are not favourable, so that we are better of going straight to renewables with potentially some further construction of fision and/or fusion power to meet specific needs (marine transport comes to mind).

  11. I really don’t understand why we should worry about waste heat from human activity. Now and in the near future it’s negligible compared to the forcing from man-made GHGs, as the article makes crystal clear.

    The chart below – one of many interesting climate and energy charts available via the site of James Hansen and Makiko Sato – shows that the global energy consumption from waste heat generating sources (fossil & nuclear) was about 12 gigatonnes of oil equivalent in 2015. One tonne of oil equivalent is 42 gigajoules, so that represents a forcing of 0.031 watts/m2, slightly more than the number given in Flanner 2009, but still negligible. If the waste heat generation increased to 0.059 watts/m2 in 2040, it still wouldn’t be more than the CO2 forcing in 1874 or methane forcing in 1891 (relative to 1850), and nobody can claim that these greenhouse gases were a serious problem at that time.

    Energy chart

    What if the waste heat increased to a level equal to the modern CO2 forcing, about 2 watts/m2 relative to 1850? That would be 6 doublings or 64 times more than the 2015 number and finally enough to have a significant impact on the global climate, but it would still be a pretty minor problem. Why?
    Look at the energy consumption chart again. Since 1900 the energy consumption from fossil & nuclear has increased about 20-fold. What has all that energy done in addition to releasing a negligible amount of waste heat and a far more significant amount of GHG?

    It has powered almost all the human activity in this period!

    That includes urbanisation, transportation, agriculture, deforestation, mining, hunting, pollution and all kinds of economic activity that have caused large scale fragmentation or complete destruction of natural habitats and an increasing rate of extinctions. This is of course possible with muscle power too, but it’s much, much easier to, say, cut down a tropical rainforest with fossil fuel powered chainsaws and machines than with muscle powered axes.
    The GHG emissions from fossil fuel is definitely a serious problem, but I will claim that it pales compared to all the habitat destruction that has been made so much easier by all the energy available from fossil fuels. The fragmentation of habitats has also made the remaining pockets of nature more vulnerable to climate change, as it makes it harder for many species to adapt by migrating to other places.

    How can anyone imagine that it would be possible to increase this energy consumption and the related human activity by a factor 64 or even 256 (8 doublings) without completely wrecking the last remains of nature on this planet? What on Earth would we need all that energy for? An American lifestyle for hundreds of billions of humans? How should we feed them? Does anyone actually believe it would be possible to transform Earth to a global city akin to Coruscant in Star Wars without a complete destruction of all ecosystem services? A few watts of waste heat per square metre really is a trivial problem compared to this.

    Believing that human waste heat could grow to a level with significant global climate impacts without far more devastating consequences for all life on Earth isn’t just unrealistic, but complete madness!

  12. Responding to comment here.

    " it would be correct to state that such an atmosphere does not radiate IR."

    Anything with a temperature above absolute zero must radiate, including gases nitrogen and oxygen. What nitrogen and oxygen do not do is absorb IR (and then reradiate it).

    You seem to missing the fundimental point that exergy fluxes must balance. At any level in the atmosphere, the outgoing energy must balance incoming radiation. (and think about what "heat" is. Why discount ground heated by sun). If radiation reaching the surface (say) increases (as it does because of IR being reradiated when GHG increases), then temperature of surface must increase till outgoing radiation matches the incoming. Grab a physics textbook and revise blackbody radiation and Stefan-Boltzmann law.

    Heat is absolutely radiated to space all the time - and is measured by satellites. The amount of outgoing IR and its spectrum are completely consistent match GHG theory with extraordinary precision.

    If your notions were correct, what would you predict IR sensors on satellites would detect?

  13. scaddenp @162,

    The theory that all things hot radiate is a bit simplistic in this context. Absorbivity and emissivity are strongly connected. A shiny solid does not absorb so well and also does not emit so well. This is because the mechanisms that absorb are the same as those which emit.

    Thus N2 absorbs & emits only at very short wavelengths below 0.2 microns. O2 is a bit more reactive at lower energy radiation with absorption/emitting bands either side of visible light. There are also weak bands in the near IR at about 1 micron.

    But at lower energies deep in the IR, diatomic molecules like O2 & N2 simply do not have the flippy-floopy wobbles that are required to capture/emit longer wavelengths. So they cannot of themselves be warmed by such radiation or cool by emitting such radiation.

  14. MA Rodgers - fair enough, but main point was the AEBanner seems to be neglecting outflow to space. There is what seems to me a pretty wierd idea that heat from burning FF cannot result in radiation to space.

  15. Energy can cause Global Warming

    As we have relocated to a new thread, I think it might be helpful for possible new readers if I were to mention again my wordpress post at

    MA Rodger @217 Big Picture

    Thank you again for your recent post, but I am afraid I’m rather puzzled about some of your questions.
    Quote 1. “If the 97% of the warming that didn’t end up in the atmosphere didn’t result from the AGW, what was the cause of it?” End quote.
    I cannot quite see what you are getting at here. But my best assessment is that, for the period 1961 to 2003, 31% of the increase in global heat content came from geothermal sources, 11% from anthropogenic energy and the remaining 58% presumably from the Sun. But this is puzzling, because for Earth’s energy balance, the energy received from the Sun is equalled by the energy radiated back to space.
    Quote 2. “And happily your numbers are not inaccurate within your grand theory that CO2 at 288K cannot emit photons at 15 microns because the energy of such a photon is roughly twice the average kinetic energy of a molecule in such a gas. But do remind me - what is the minimum number of gas molecules you require to create a collision? There is further consideration of the statistical profile of molecule velocity and the other means such molecules have of holding energy.” End quote.
    Firstly, I should like to clarify this point about the kinetic energy of a molecule at 288 K. It is not the average kinetic energy, whatever that means here, but the total kinetic energy of the molecule. In other words, even if the colliding molecule could somehow give up all its energy to the GHG, it would still be less than half that required to enable a subsequent photon.
    I think the answer to your question is probably 2, but the probability of an instantaneous collision involving more than 2 is very small, in view of the extremely short times taken. Subsequent collisions would have the same problem.
    However, a proper study with statistical mechanics is really needed on this matter. Please, is there a reader out there who would be prepared to consider doing this?
    Quote 3. “Simply put, to refute the existence of 15 micron IR being radiated by CO2 in the atmosphere is to popishly refute a whole pile of very straightforward physics. The IR can be measured.” End quote.
    I’m afraid you have totally misunderstood my position on this. I have never denied the ability of carbon dioxide, or any other greenhouse gas, to emit infrared photons. As you say, this is straightforward physics. A more careful reading of my posts should make this very clear.
    What I am questioning is the probability of CO2 to be raised to the required excited state by simple collision with other molecules in the atmosphere. The GHG theory does not require this; it relies on absorption of photons of the matching energy. Yes, standard physics.
    Please do not misrepresent my ideas and statements.


  16. AEBanner @165.

    Running through the difficulties your grand theory has to dodge.

    QUOTE 1

    If we were to divide up the global warming and allocate it to a source (as you do) - 11% to FF/Nuclear, 31% geothermal, 58% "presumably" the Sun - we are left with a highly unsatisfactory outcome. Firstly, this 11% value is a shift from your initial position which (@207 of a different thread) was suggesting that the FF/Nuclear input was "enough to explain the measured warming of the Earth's atmosphere." This is not saying four-times the measured atmospheric warming which is what you set out now. Secondly, where does this 11% value come from? Are you assuming the 159Zj of total global warming 1961-2003 set out in IPCC AR4 Fig 5.4 comes to something like 0.27Wm^-2 and the FF/Nuclear flux is calculated as some 0.03Wm^-2?  [NOTE - you may set this out on your web-page but if it is not set out here I am ignoring it. Your web-page is being 'corrected' so is not a 'published' source.] Thirdly, the geothermal energy flux is constant over time. Were this responsible for 31% of AGW which is running at 0.2ºC per decade, we would expect to have seen a 0.6ºC increase in global temperature over the past century and the century before that; indeed a 6ºC rise over the last millenium. Such a rise has not happened. Fourthly, IPCC AR4 Fig 5.4 provides values for the period 1993-2003 (0.55WM^-2) which are twice the rate of warming of the earlier period implying the earlier period averaged 0.14Wm^-2, a four-fold difference between the two periods. How can this be if the largest but 'presumed' energy flux in this grand theory was solar energy which has been declining over the period. Fifthly, if these energy fluxes from FF/Nuclear, Geo, Solar arrive within the global system and have no effect on the energy fluxes exiting the global system thus warming the global system, the energy accumulated then lost through the 11-years solar cycles would be an interesting and measureable test of your system as it is rather large. Where is this energy fluctuation?

    QUOTE 2

    You don't seem to realise that the kinetic energy of a molecule within an gas is not fixed. There is a large distribution of velocities (& differing masses) as the whole bishes and bashes iteself within the volume. And there are lots and lots of molecules and lots and lots of collosions, that relative to the number of photons emitted. You do seem to arrive at some of this learning yourself as you begin by misinterpreting the word "average" and end by asking for help in Statistical Mechanics.

    QUOTE 3

    Firstly, you misinterpret the mechanism by which an IR photon escapes the planet, this a matter of "standard physics." You are assuming that a CO2 molecule that captures such an IR photon will then wiggle for a while before shooting the IR photon away in some unspecified direction, this allowing an upward migration of IR photons up and out of the atmosphere. If this were true, the origin of the IR photons should be considered, so see the second point below. While essentially the process results in an outcome not greatly dissimilar to it being true, the "standard physics" says it isn't true. While a CO2 molecule will take on average tenths of a second to emit a photon from its excited state, such a molecule is in collisions in milliseconds. As the excited state is a mechanical wobble, a collision will interfere with the wobble and the energy is almost always (given the large number of collisions) absorbed by the air. The photon is emited by subsequent collision-induced excited states which are many more than photn-induced excited states. Secondly, you misinterpret yourself!! If the 15 micron IR photons do not originate from air but are simply transmitted through the air abet with CO2-redirections: if this were true, where do these photons originate from and where do they end up? If the atmosphere is a neutral transmitter, the origin must be the planet surface. And the destination must either be back to the planet surface or outer space. If the former were to increase, less photons escaping into space, this will of course result in an increase in temperature and thus an increase in photons launched up into the atmosphere. Golly, have we just stumbled upon a wrming planet and way of cooling down the warming? How does that impact your grand theory which has no such mechanism?

  17. Energy causes Global Warming

    michael sweet @218 Big Picture

    Volcanoes; yes, very interesting.
    But first I wish to make a distinction between sensible heat and radiant heat. Sure they are both forms of heat energy, but they need to be considered differently in the Earth’s system.

    Sensible heat is the energy of the molecules in a gas due to their motion; that is their kinetic energy.
    Radiant heat is the energy of an emitted electromagnetic photon. In general, this energy is greater than the kinetic energy of a moving molecule.

    Radiant energy is due to the vibrations of the atoms and molecules in a solid and a liquid. The so-called “black body” radiation.
    The nitrogen and oxygen molecules in the atmosphere do not vibrate, and so they cannot emit radiation. The GHGs, of course, can absorb and thence re-emit photons of infrared energy.

    The energy given out by a volcano consists partly of the sensible heat of the gases, and partly radiant energy from the hot lava and adjacent land surfaces, and the hot material particles also ejected. So, the radiant energy can, indeed, be emitted to space.

    The sensible heat energy goes mainly into the oceans, as we can see from the Figure 5.4 taken from the IPCC AR4 report and conveniently reproduced for us by MA Rodger in his post @215 Big Picture. Once in the oceans, the energy can then be radiated away to space.

    I hope this answers your question satisfactorily.

  18. Energy causes Global Warming

    scaddenp @162

    I think the post by MA Rodger @163 and my post @167 answer your points adequately.

    Of course, energy fluxes must balance where possible, as with energy from the Sun.
    But, if additional energy enters the system and cannot be radiated away, then the temperature will increase.

  19. AEBanner,

    Your answer does not begin to answer my question.  

    You claim in your answer the "sensible heat" from volcanoes goes into the ocean.  You do not say what fraction of the heat that is.  Obviously the same fraction of volcanic "sensible heat" has to stay in the atmosphere as the fraction of human waste heat.   The ocean has no way to determine what heat is volcanic and what is human waste heat.  

    Let me presume that 97% of the heat goes into the ocean while 3% remains in the atmosphere.  97% of volcanic heat is still much more than the waste heat humans release.  In addition, you do not count the 3% remaining in the atmosphere when you make your calculation of accumulated waste heat.  If you count this heat in your calculation it will make the temperature go up way too much. 

    If 97% of the volcanic heat went into the ocean for 4 billion years (we can neglect that 4 billion years ago the volcanic heat was much higher) and accumulated there as you claim the ocean would have boiled away.  Obviously that has not happened.

    Please explain why all the accumulated heat has not boiled away the ocean.  

    Obviously the "sensible heat" from volcanoes has gone somewhere.  Scientists say that it has radiated out into space from black body radiation with the rest of the energy, including the "sensible heat" that humans have released. I have shown that it cannot accumulate in the ocean as you said.  Where do  you now say it goes????

    A word from an old chemistry teacher: when you do not understand what black body radiation is you cannot discuss the Earth's energy balance intelligently.

  20. Energy causes Global Warming

    MA Rodger @ 166

    Thank you again for a confused post, but I was saddened to find that you do not seem to have read my post on wordpress. I deduce this from your statement
    Quote “[NOTE - you may set this out on your web-page but if it is not set out here I am ignoring it. “ End quote.
    Please tell me that you have indeed read my blog.
    If you have not yet read it, then please grant me the courtesy and agree to read it.
    This is the link to assist you.

    You may find the derivation and the excellent results intriguing.

    Another point, your quote 2. What is your problem with asking for help with a truly difficult task, such as the need for assistance with Statistical Mechanics, which is where we got to in our recent posts. Such a study could well resolve any difficulties.
    I really hope this could be achieved, whatever the outcome.

    Anyway, if you cannot bring yourself carefully to read my blog, then I see no further point in debating the issues with you. Please let me know your decision.



    [DB]  Inflammatory snipped.

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Moderating this site is a tiresome chore, particularly when commentators repeatedly submit inflammatory or off-topic posts and simply avoid answering questions put to them. We really appreciate people's cooperation in abiding by the Comments Policy, which is largely responsible for the quality of this site. 
    Finally, please understand that moderation policies are not open for discussion.  If you find yourself incapable of abiding by these common set of rules that everyone else observes, then a change of venues is in the offing.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

  21. AEBanner @170.

    Why would anybody expect a discussion of something not set out here at SkS that is non-published-&-still-being-amended. If your derivations and results are "excellent" & "intriguing", then bring them here for discussion!!! Of course, you will not be able to amend what you write about them, but that is a good thing, an honest thing.

    So bring it here or be gone yourself. And if you do remain, I will not let off correcting your comments while they continue here.

    As for Statistical Mechanics, the criticism was not in appealing for expertise in such a field, but that beforehand you bizarrely tried to suggest that an average kinetic energy of a gas molecule (a statistical quantity representing a measure of the total kinetic energy of each molecule) was different from the total kinetic energy of a gas molecule (which of course will vary from molecule to molecule).

  22. Energy causes Global Warming

    michael sweet @169

    Thank you for your new post. I’m sorry you believe I have not answered your questions about volcanoes. I thought I did quite well.

    However, if you wish, I shall be happy to try again. But this may incur some repetition in parts, for the sake of clarity and continuity.

    I feel sure you agree with my opening remarks in my initial response to you @167.
    And I do, in fact, know what “black body” radiation is about.
    But in my reply to you @167, I did not bring up the figures of 97% or 3%. So please let me know which of my posts you are concerned about. It would seem to be additional to your initial post. OK, no problem.

    Anyway, back to the volcanoes. As far as I know, the output from a volcano consists of hot lava, hot material particles, and much heat energy in the form of sensible heat, that is kinetic energy. And, of course, the adjacent land area will also be raised in temperature.

    The hot materials including lava, particles and the hot adjacent land will radiate energy, in line with black body radiation, which ultimately escapes to space. The sensible heat in the form of kinetic energy of the air molecules mainly enters the oceans, in line with the 97% value you are no doubt referring to from the IPCC AR4 report, and Kevin Trenberth’s 3% into the atmosphere. ( This latter subject to further interaction with the oceans and associated subsequent radiation.)

    But the important thing here is that the oceans, being liquid, will also radiate, eventually to space, and this will proceed to maintain a satisfactory balance. Yes, the volcano emissions started billions of years ago, but so did the balancing radiation, so maintaining a satisfactory temperature for the Earth’s surface, and not boiling away the oceans.

    Please let me know if I have not covered some matter you are concerned about.

  23. Energy causes global warming

    I should be very pleased to hear privately from anyone interested in this topic by e-mail at


  24. AEBanner,

    You contradict yourself.  You have claimed that sensible heat emitted by humans accumulates in the atmosphere.  Yet you now claim that sensible heat from volcanoes is emitted to space as radient energy.  A contradictory argument can automatically be dismissed.

    You cannot have it both ways.  If human heat accumulates than volcano heat must also accumulate.  If volcano heat is emitted to space than human heat must also be emitted.  Since the volcano heat is so much greater it is the dominant effect.  

    Scientists have shown that waste heat is emitted to space in the year that it was created.  It does not accumulate from year to year as you claim.  It is interesting that the integrated amount of waste heat is the same order of magnitude as thje increased heat in the atmosphere, but we already knew that: it has been previously discussed here at Skeptical Science.

    I taught introductory college chemistry, including black body radiation,  for 10 years.  It is clear from your posts that you have no idea how black body radiation works.  Your calculations up thread demonstrate that to anyone who understands radiation.  

  25. Energy causes global warming
    michael sweet @174

    Thank you for your comments.  It seems that I was unable to help you. 

    Sorry about that.

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