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It's waste heat

What the science says...

The contribution of waste heat to the global climate is 0.028 W/m2. In contrast, the contribution from human greenhouse gases is 2.9 W/m2. Greenhouse warming is adding about 100 times more heat to our 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)

When humans use energy, it gives off heat. Whenever we burn fossil fuels, heat is emitted. This heat doesn't just disappear - it dissipates into our environment. How much does waste heat contribute to global warming? This has been calculated in Flanner 2009 (if you want to read the full paper, access details are posted here). Flanner contributes that the contribution of waste heat to the global climate is 0.028 W/m2. In contrast, the contribution from human greenhouse gases is 2.9 W/m2 (IPCC AR4 Section 2.1). Waste heat is about 1% of greenhouse warming.

Radiative forcing from waste heat vs anthropogenic greenhouse gas radiative forcing

What does these numbers mean? They 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. Greenhouse warming is currently adding about 100 times more heat to our climate than waste heat.

Last updated on 27 July 2010 by John Cook.

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Comments 51 to 77 out of 77:

  1. johnd writes: Ned at 22:36 PM, part of the issue being discussed was whether waste heat accumulates or not, and whether accumulative it's effect is more than negligible.

    There is no magic mechanism that removes heat from the atmosphere if it originally came from radiation but lets it accumulate if it originally came from combustion or whatever.

    IMHO these analogies to revolving doors and traffic jams seem to have no effect other than clouding the issue. How about some actual evidence, please? Doug B. gave a reference to a paper with quantitative comparison of the two sources way back in comment #2. That was very helpful, I think.
  2. Actually this thread is helpful because it's serving as a remarkably clear and concise example of how so much of this "debate" is ultimately driven by complete and total intractability on the part of some of the discussants.

    This is a very simple situation. "AHF" is capable of adding something like 1% of the quantity of solar heat being retained by additional impedance due to C02 and knock-on effects, working from mainstream estimates of anthropogenic GHG climate sensitivity.

    Just to make things clearer, let's imagine for a moment that we're somebody akin to Dr. Roy Spencer, a highly-qualified scientist able to make a start on articulating an alternate hypothesis to anthropogenic warming as an explanation for recent observed temperature increases. Under our Dr. Spencer-style hat, we believe that effective AGHG forcing is only 10% of more commonly accepted figures. In this circumstance we're looking at AHF forcing still being just 10% of anthropogenic GHG forcing. Even if we assume mainstream estimates are off by a full order of magnitude, AHF still pales in significance compared to anthropogenic GHGs, is still yet another order of magnitude less.

    Meanwhile, as has been pointed out, heat is mindless and does not care from where or to where it's going. Whatever heat is added to the pool here on Earth whether by anthropogenic liberation or arriving from the sun or for that matter emerging from retained and radioactive decay heat from within the Earth is going to find its way to the great beyond regardless of birthright, ultimately via radiation. Nothing about the origin of heat specifies its subsequent behavior.

    Heat flux from energy liberated as a part of human activity by any measure appears by all accounts to be a minor constituent of Earth's radiative energy budget. Even if one looks at the thermal impedance properties of the atmosphere from various outlier perspectives, AHF still does not measure up in a significant way.

    There's really not much to work with here for a so-called skeptic, to the point that one is left wondering how to speak patiently in the face of arguments to the contrary, once they've been repeated several times by the same person.
  3. There is one obvious problem with the whole "waste heat" argument which is this-why was there little to no measured warming between 1850 & 1900, given the amount of factories & power stations which were pumping out heat during this time? By today's standards, these factories & power stations were incredibly inefficient-meaning they gave off the vast bulk of their energy as waste heat. Yet strangely, in the last 60 years, we're expected to believe that waste heat generation is actually inversely proportional to improvements in thermal efficiency. i.e. the skeptics would have us believe that, even though thermal efficiency has improved over the last 60 years, the contribution of waste heat to global warming is increasing! That's *hilarious*. From my calculations, its fair to say that waste heat contributes somewhere around +0.006 degrees (& falling) to total global warming for the last 60 years.
  4. Another problem with the "Waste Heat" theory. Why did the planet continue to warm (due to increased solar activity) during the Great Depression, when industrial activity-world wide-fell, yet temperatures fell during the first decade of the post-war industrial boom?
    Response: Marcus, just to play devil's advocate on this line of argument, couldn't you likewise say "why was there no global warming during mid-20th century while CO2 levels were rising?" or "why was there global warming in the early 20th century while CO2 levels weren't rising that steeply?" :-)

    To fully address the question of waste heat during the industrial revolution and Great Depression, you would need to calculate the radiative forcing from waste heat over these periods. It's not that hard to work out - we do have figures on energy use over these periods (I link to the CDIAC data from here). Working this out is left as an exercise for the reader (eg - I'm too lazy to do it myself).
  5. I would hope that the term "waste heat" is not being understood simply as that portion of energy that is not delivered to the load. I can see how the word "waste might lead one to think this... thoughtout this discussion, I was referring to the broader concept. For say an automobile, waste heat should be understood as heat exchanged to cool the engine, the car's friction in all moving parts, the kinetic energy increase in the atmosphere left by drag, and combustive heat going out the tail pipe in the form of CO2 and water vapor. Similarly, house heating waste heat is not the percent of heat that escapes though a building's insulation, but every calorie used to heat the inside of a home or building; as this heat is eventually released into the environment. It is actually equivalent to the total worldwide energy consumption... 1.5 x E13 W

    http://en.wikipedia.org/wiki/World_energy_resources_and_consumption

    Hope this helps.
  6. Marcus said
    "heat from within the Earth is going to find its way to the great beyond regardless of birthright, ultimately via radiation. "

    I agree 100%, but then you go on...

    "There's really not much to work with here for a so-called skeptic, to the point that one is left wondering how to speak patiently in the face of arguments to the contrary, once they've been repeated several times by the same person. "

    I have also asked more than several times how N2 and O2 radiate? I have still to see anyone acknowledge this difficulty. There have been some indirect responses about CO2 acting as an antenna! in which case, according to this explanation CO2 is helping to cool the atmosphere, and if this were the case, all latent energy would actually be attributed to waste heat.

    But lets not go there for now please. I would just like to see an explanation on how N2 and O2 (the non GHG portion of the atmosphere) are understood to cool radiatively, as I have been saying that they cant do this and will only generally cool by convection. And only by convection to "cooler" objects such as water and ice, implying a "selective" route for energy exchange. There was that question of why poles warm faster (for instance).

    At any rate Marcus, I also agree with your statement, "so much of this "debate" is ultimately driven by complete and total intractability"...

    This is obvious. I am not sure why, as we are all in the boat together.
  7. RSVP I believe we're all clear on that. Flanner is at any rate and since his number is the operative one here we're all on the same page it seems.

    One more time: AHF (Anthropogenic Heat Flux) is something like 1% of expected forcing from anthropogenic green house gases. As I explained earlier, estimates of AGHG forcing expectations could be too large by a factor of 10 and would still dwarf AHF. "There's no there, there."

    Meanwhile you still seem to be worrying over the relationship of N2 and O2 w/waste heat. It's not a unique or special connection. Ned explained the commonality here.
  8. doug_bostrom
    I went there and (as before) read...
    "Likewise, most of the heat from GHG absorption will also be transferred to O2 and N2 molecules, thanks to the fact that each CO2 molecule collides with N2 or O2 molecules roughly one billion times per second."

    On the one hand, the more you defend CO2's efficiency in transferring energy, the less significance you are actually attributing to the effects of CO2 concentration level.
  9. RSVP #58

    "On the one hand, the more you defend CO2's efficiency in transferring energy, the less significance you are actually attributing to the effects of CO2 concentration level. "

    Ummm. No. These are two separate processes that are physically independent. Your logic is wrong, and your physics is deficient.
  10. RSVP #30, no you really didn't answer my questions - but hey, why not;

    1: No.
    2: Same as all other heat... it radiates at equal intensity in all directions.
    3: "energy dissipation" is two words... and two words neither you nor I have used. Ergo, it is impossible for me to determine what meaning they are meant to have "in this context" because there is no context.
    4: Same as all other matter in the universe... they absorb some wavelengths of EM radiation and allow others to pass through. Absorbed radiation is (per issue 1 above) then re-emitted, though possibly at a different wavelength.
    5: The wavelengths involved are different. Specifically, Nitrogen and Oxygen are largely 'transparent' to the infrared wavelengths emitted by the planet's surface while GHGs are not.

    BTW, your hypothesis seems to depend on a belief that waste heat 'goes into' N2 and O2 and stays there (which is completely wrong) while solar heat somehow avoids those two elements. Which is, of course, pure nonsense.
  11. I agree 1000% with Doug Bostrom's comment up here, both in terms of the substantive issue and the reflections on the context that Doug offers in the first and last paragraphs.

    There is nothing wrong with having people come here and ask basic, even naive, questions. Like Doug, however, I am uncertain about how we as a community should respond to someone who continues to make the same fundamentally wrong claims over and over again, running over all explanations and corrections like an implacable bulldozer of willful ignorance.

    We have seen this before with other commenters (e.g., a certain commenter in this thread). Most of the people who comment on this site do so in good faith, with the expectation that their efforts to promote understanding won't be wasted. The presence of a commenter who is more or less impervious to reasonable discussion and the mutual sharing of ideas throws a large spanner into the works.
  12. I thought I would give RSVP a try.

    Essentially all of the IR from the surface is absorbed by CO2 in the atmosphere and is not radiated directly into space. (Your example of 5% absorbed is incorrect). You would not see lights in fog, you would see an evenly lit background. When CO2 absorbs IR energy, it transfers most of that energy as heat immediately to the surrounding N2 and O2 by collisions with those molecules. Waste heat is absorbed by the atmosphere (primarily O2 and N2) in various ways. Once the atmosphere absorbs heat, from any source, it is all treated the same. -->The N2 and O2 transfer their heat back and forth with the CO2. The heat is transferred around the atoms of the atmosphere (primarily by collisions) and eventually comes to another CO2 molecule. It is then re-radiated as IR. Some IR goes up and some goes down. By chance, after a long path with many absorbtions and re-emmisions, the IR is emmited into space. Increasing CO2 causes the path the heat follows from the Earth into space to be longer and heats up the atmosphere. Since the amount of waste heat is 100 times lower than heat from GHG, it is not significant.

    Do you have any questions about this explaination?
  13. Michael Sweet:
    Increasing CO2 causes the path the heat follows from the Earth into space to be longer...

    Somehow I've not seen the process described quite that way before.

    Delayed by rerouting, balance only restored as emissions and collisions become sufficiently frequent as to overcome the delay, leaving the atmosphere more stuffed with activity or that is to say warmer.

    Thanks! Also thanks to RSVP for forcing Michael to produce that model. Others probably already had it in mind, me not in quite such a succinct way.
  14. michael sweet at 08:12 AM on 28 July, 2010 said..

    "By chance, after a long path with many absorbtions and re-emmisions, the IR is emmited into space. Increasing CO2 causes the path the heat follows from the Earth into space to be longer and heats up the atmosphere".

    I have a question if you'll permit me.
    IR photons travel at close enough to the speed of light, (about 300,000km per second).
    With that in mind, do we know HOW LONG this delay you are talking about is? And how does it relate to the rate of cooling observed overnight?
  15. Baa Humbug - The transit time of a photon in flight isn't going to be very long; but the number of absorption/emission events will certainly increase. Each absorptio/emissionn takes some time, with a probability of transferring that energy to other gas molecules instead of re-emitting; each emission (from the same GHG molecule or another one excited to emit by the thermal state of the air mass) takes some time as well.

    So longer transit distance = more absorption events = more chances to heat the air rather than just being re-emitted.
  16. Baa Humbug:
    I would say the same as KR. Keep in mind that a single photon does not make the whole path, this is a simple model. If the path is longer, with most of the time spent absorbed by a molecule, it will take the heat longer to escape. The speed of the photon does not matter. When the path is longer for heat to escape but the source of heat (the sun) stays the same that means heat accumulates in the atmosphere. I am sure that the time delay could be calculated, but what scientists find useful is the forcing. Cooling overnight is a different process. The time for the heat to escape is longer at night with more CO2 just like during the day. The situation is complicated by water but the essential details are the same.
  17. I couldnt get the full version of Flanner 2009, so I cant see how he concluded that waste heat is so small relative to GHG forcing.

    I have a “burning” question.

    I lit a small pile of logs under last night’s moon, enjoying the fire’s warmth and watching sparks and smoke convecting towards the cosmos. Amongst the smoke was some of that awful carbon pollution, and I wondered about the heat that could be added to the planet from CO2 if it had a residence time of say 1000 years. How did the GHG forcing energy compare to the energy released by the simple exothermic oxidation of the photosynthesized ligno-cellulosics (aka fire) ?

    I made my own calculations about this (below), and then looked around the web until I found the topic thread here about waste heat vs GHG forcings. I’ve read through this thread and Flanners 2009 abstract (couldn’t access the full paper) which says that waste heat is small (1%) compared to GHG forcing.... quite the opposite of where I got to. So have I calculated wrongly ? Why are my conclusions so different to Flanner?

    Here is my reasoning....

    Assumptions
    1.A tonne of burnt coal (78% carbon) releases 2.86 tonnes of CO2; the energy content of coal is about 24MJ/kg
    2. About half of CO2 from current annual hydrocarbon burning ends up back into the biosphere and the oceans, the other half stays in the atmosphere.
    3. Atmospheric CO2 has a residence time in the order of centuries
    4. Doubling CO2 is like adding the equivalent of 3.7W/m2 warming energy, around the clock.
    5. If atmospheric CO2 is doubled, eg from 290 to 580ppmv (ppmv * ~1.5 = ppm by mass) , then atmospheric mass of CO2 goes from 2350 to 4700 Gt ( 10^9 tonnes).

    (nb. Annual hydrocarbon-derived CO2 emissions are presently about 30Gt/yr, historically we have released about 1200 Gt hydrocarbon-derived CO2 since 1850 (of which 400Gt since 1990) , and atmospheric mass of CO2 has increased by about 800Gt since 1850 (current mass 3150 Gt).

    I thought it would be easier to deal with some human-scale measures here, so converted as follows:

    If we allocate CO2 mass evenly across the surface of the Earth (5.1×10^8 km2), that means that the atmospheric column above each square metre contained about 4.6 kg CO2 in yr 1850 (290ppm). Doubling CO2 thus means adding another 4.6kg/m2, so at the ratio of gas:solid of 2.86:1 and with only about half of the CO2 staying in the atmosphere, doubling CO2 from 1850 concs would require burning about 3.2 kg of coal-equivalent for every square metre on the planet.

    From point 4 above, the additional 4.6kg of CO2 produced by burning 3.2kg of coal leads to 3.7W x 24 hours x 365 days = 32.4Wh per year.

    Watts and Joules can be converted as follows...a Watt is a unit of power which measures how fast energy (measured in Joules) is converted, 1.0W = 1.0 J/sec, so 3.6kJ = 1.0 Wh.

    So; from 1. above, Burning 3.2kg of coal liberates 77 MJ of energy (3.2 x 24) , and
    from 4. above, the energy “forced” into the climate system by adding 4.6kg CO2 which stays there for 660 years , is 32.4Wh/yr x 3.6kJ/Wh x 660yrs =77 MJ.

    In other words, the energy from burning a piece of coal (“waste heat”) is equal to the GHG forcing energy of the CO2 created by burning, if and only if the CO2 stays in the atmosphere for 660 years. It seems that greenhouse warming in the short-term (eg decades) is therefore only a miniscule fraction of the actual combustion energy released.

    To me this conclusion begs the question, if it takes 660 years for the greenhouse heating energy to be the same as the energy released by burning, how come we aren’t already more than toasted by the simple act of combustion itself? And where is all that heat from the fires going? In one year, it’s 660 times as much as the GHG forcing energy, quite the opposite of what Flanner 2009 said.

    If the waste heat from combustion is not staying in the atmosphere (or oceans), why would the early-evening near-ground greenhouse warming be any different?
  18. hillbilly#67 : "where is all that heat from the fires going?"

    The surface of the earth radiates at 288K (~14 C); suppose your fire burns at 400C (673K). The radiated power varies with the 4th power of temperature (in K); there's a huge difference between 2884 and 6734. So the short answer is hot objects lose energy as infrared radiated to space very rapidly. See recent IR photos of wildfires (example here).

    See the Stefan-Boltzmann law wikipedia article for a reference.
  19. Thanks Muon, The IR photos and S-B ^4 were helpful explanations for my small open fire, but you are really referring to temperature, not heat energy. I can think of two situations where the temperature is lower and the explanation may not hold. For example I can cover or contain the fire, or make it burn very slowly.

    The waste heat from a coal-fired power stations CFPS is ultimately equal to the energy content of the coal. It just comes out in various forms, steam from condensation towers, cooling water re-circulated in dams, the walls/roof heated by boiler radiation, transmission resistance in lines, and finally the actual electricity produced that goes into lighting or electric motors or whatever, all of which give off some low grade heat. So most of that waste heat from the CFPS is in fact similar to the background and would therefore seem to have as much chance of being absorbed by CO2 (or H20) as the night time losses from the natural land/water surface.

    And what if the coal was burnt very very slowly? For example, like a rotting log. Suppose it takes 10 years to decompose the 3.2 kg of coal in my first question. The heat (energy, not temperature) liberated by oxidation is still 24 MJ//kg, and it will still take 660 years for the warming produced by GHG emission to equal that amount. (assuming CO2 is already doubled so it has the effect of warming at 3.7W/m2).

    So it seems if you take out the rapid IR loss, the conclusions from my fire analogy still stand. The GHG warming energy from the emitted CO2 (in the short term) is a miniscule fraction of the energy released by combustion.

    Why is that GHG warming energy (night time only , near ground) not lost from the system as easily as the combustion energy?
  20. hillbilly#68: "you are really referring to temperature, not heat energy."

    You asked about the heat from your fire, a high temperature source.

    But the real question is indeed the comparative quantity of energy -- and a daily average of 250 W/m^2 across a verrry large number of m^2 represents a lot more watts than fires, power plants and cars. Hence the waste heat = 1% of GHE conclusion.

    You're coming to this thread quite late; I suggest you review the prior comments here as well as the 400+ comment thread Waste heat vs. greenhouse warming. One of the key questions raised there was this: why the continued warming during times of economic downturn when waste heat input declines?
  21. mullumhillbilly @67, accepting your figures for the sake of argument, I come to your calculation of the energy input from the greenhouse effect. Specifically, adding 4.6 Kg per m^2 atmospheric CO2 (doubling from pre-industrial levels) results in an a forcing of 3.7 W/m^2.

    3.7W/m^2*(60*60*24*365.25)seconds = 116.76 MegaJoules for a single year, not the 77 MegaJoules for 660 years that you calculate.

    The error appears to be where you write:

    "From point 4 above, the additional 4.6kg of CO2 produced by burning 3.2kg of coal leads to 3.7W x 24 hours x 365 days = 32.4Wh per year."


    In fact, 3.7 *24 * 365 = 32,412 WattHours, not 32.4 has you calculate.

    Returning to the correct value, by your corrected estimation burning 3.2 Kg of coal per m^2 of the Earths surface would release 76.8 MJ/m^2, which would rapidly dissipate. The CO2 from that combustion would have a forcing of 111.76 MJ/m^2 per year for 660 years, or 73.7616 GigJoules, or 960 times the amount.

    This in fact underestimates the effect of the greenhouse forcing for it does not take into account feedbacks, which increase the amospheric forcing of the CO2 to 8 to 10 W/m^2 (sorry, don't have the exact figure to hand). That at least doubles the effect.

    As you can see, by these back of the envelope estimates, the estimate in the article above estimate is conservative by a factor of 100. This is because it compares current greenhouse forcing with current annual non-renewable energy production, and does not include the life time effects of CO2.
  22. Correction to 71: where I said conservative by a factor of 100, that should be by a factor of 10.
  23. OK thanks Tom@71, I accept that correction to my arithmetic. So in fact the GHG energy effect is equal to the combustion energy in just 0.66 years !! (32.4kWh/yr x 3.6MJ/Wh x 0.66 yrs =77 MJ). That's just as wierd from the opposite end, hundreds of times more energy from the byproduct than in the combustion ??!

    BTW I thought the 3.7 W/m2 per doubling did already account for the feedbacks (at present with 0.33 doublings, it's 1.66W/m2 incl all feedbacks?) IPCC AR4 Fig 2
  24. Muon @70
    Here’s a thought experiment. It doesn’t require believing that the atmosphere behaves literally like a greenhouse.

    Suppose we have two identical glasshouses a few metres apart, each of them with 70% floor area covered by water (let’s say a metre deep ie a large heat sink compared to the remaining area of lightly gravelled dry floor). Further suppose this is a special kind of glass which is completely transparent to all radiation wavelengths. By day, the doors are opened and the roof is vented so air and surface temperatures and humidity are same as the surroundings. All vents closed at sunset, and one glass house has extra CO2 added (at ambient temperature) so that it has say 256x the concentration of the other (8 doublings). Surplus air is vented so that pressure is also constant. Heat energy within the enclosures is equal at the start of the night. Then as the night cools, heat in the form of longwave infra red radiation LIR is emitted from the ground and the water. So what happens to the temperature and heat energy vs time profiles in the two glasshouses?

    What I think will happen is this. In the CO2 enriched state, more of the outgoing LIR is intercepted and re-radiated. Some of the re-radiation leads to (i) collisions with N2 and 02 thus raising the air temperature (kinetic energy) and (ii) greater evaporation and higher water vapour content in the air. So a temp-vs time and heat energy content vs time chart of the CO2 enriched state would show slower declines than the ambient air state. However both greenhouses are ultimately losing their heat to the surroundings. If kept in the dark for long enough, they will both fall to the same temperature in equilibrium with their surroundings.

    So, the key question here is how long does it take for the two glasshouses to get to the same temp and contained energy state? The area between the two temp-time or energy time decline curves is the quantum of GHG warming. If we measured temperature on a minute-by-minute basis through the night, we’d find that the “average” temperature has increased in the CO2 enriched glasshouse because the early evening temperature is higher for a period. However if we only measured overnight minimum and daily maximum, then provided the time to cool to equilibrium was less than 12 hours, there would be NO apparent difference between the two. The enriched system still returns to the same overnight minimum as the control, it just gets there a bit more slowly.

    Is this what is happening in the atmosphere (and oceans)? If the energy states equilibrate overnight, then average temperature has increased because of the early evening slower decline of the curve, but climate HAS NOT CHANGED because ultimately the energy states of the control and enriched systems are at the same point each morning sometime before dawn. The CO2 enriched system has not “gained” any energy to be carried forward (in say the water bodies). Over the long term, we would see NO energy gain in the enriched system, even though we have observed a rise in average temperature. With no accumulating energy gain, there is nothing to drive the hurricanes, floods, droughts, heatwaves, snow dumps, melting ice etc etc.

    Can anyone point me to a paper which shows empirically that overnight heat energy loss from the Earth’s atmosphere does NOT equilibrate before dawn, so that energy is actually accumulating in the system (and thence “climate change”) ?
  25. mullumhillbilly @73, it does indeed sound weird, but only if you think of the CO2 as providing the energy. In fact it doesn't, rather it helps retain the Sun's energy more efficiently, and that retaining the Sun's energy more efficiently should retain more energy at the surface than is generated by a coal fire is not weird at all.

    The IPCC figure shows only forcings, not feed backs. The difference is that the effect of a feedback is a function of temperature in the short term, as for example with the water vapour content of the atmosphere. In contrast, industrial production of aerosols, and aircraft contrails (as two examples) are not a function of temperature in any meaningful way.
  26. mullum#74: Try this thought experiment.

    The topic of this thread is waste heat. Your glass greenhouses are of no relevance.

    But you're already in full-fledged GHE/AGW denial mode, consistent with some posts under the same name on other blogs. SkS runs a bit differently than those blogs: I suggest a thorough review of the various policies here, including the Newcomer's Guide and especially the Comments Policy, where you will note some language advising against using all caps. Use the Search function to find a thread of interest and pose questions relevant to the thread. There are nearly 170 skeptic 'arguments' addressed in considerable detail.

    Most important of all, you won't get away with denying the evidence, as in: "With no accumulating energy gain, there is nothing to drive the hurricanes, floods, droughts, heatwaves, snow dumps, melting ice etc etc". A general principle of science is this -- if you have a premise (in your case, there's no climate change) that conflicts with multiple lines of evidence, your premise is probably incorrect.

    Stick to the science; avoid forming opinions based on speculation about pots of water, balloons, sheets of plywood in the sun and glass greenhouses.
  27. mullumhillbilly @74, your experimental design would not work because: (a) you have not controlled for back radiation; and (b) the CO2 atmosphere in your experiment would have approximately the same temperature as the surface, thus precluding any greenhouse effect.

    In contrast, in nature there is no back radiation from space, and the CO2 in the upper troposphere (from which most IR radiation absorbed by CO2 is reradiated to space is much colder than the surface of the Earth because of the adiabatic lapse rate. These two factors make it difficult (though not impossible) to model the greenhouse effect in a simple small scale experiment; a fact that has lead many people (including the Myth Busters) to develop essentially flawed experiments.

    Despite that your thought experiment is an interesting approach. However, you cannot apply it to the macroscale as you do. The systems you describe "equilibriate" when average energy in matches average energy out. However, the energy in at night consists of the cosmic microwave background radiation (<< 1 W/m^2), the geothermal heat (0.1 W/m^2), and industrial waste heat (0.03 W/m^2) plus a few very minor terms from meteor impacts, cosmic rays and the like. That means to reach equilibrium the temperature would need to drop to less than 65 degrees K (less than - 208 degrees C). The lowest temperatures on Earth are found in the Antarctic in winter, when it sometimes drops to -100 degrees C, but even there, equilibrium night time temperature is never reached. Six months of darkness is not enough to reach an equilibrium night time temperature on the surface of the Earth.

    Only a minority of the thermal inertia that means equilibrium night time (or day time) temperatures are never reached on Earth are a consequence of the greenhouse effect. But it certainly means heat from the greenhouse effect can accumulate from day to day, and year to year.
  28. Muon@ 76. Yes I am new to posting on this site, and I assure you I'm not a reincarnation of any previous posters. I am wading through the long "waste heat" thread you referred to earlier; I didnt know it existed when I first posted here... bit confusing I think having two threads on the same topic. As to sticking to the science, that's what I am attempting. This site is, after all, called "Skeptical Science", so I think its appropriate to ask questions, no? Sorry about the caps, I haven't discovered how to use bold or italics here, and didnt think it was even possible except I see that Tom in 77 has just done so. I'm happy to take the glasshouse questions elsewhere if you can suggest the appropriate place.

    Tom@77. I did say "in equilibrium with their surroundings", but didnt mean that to include the entire galaxy :-). Both glasshouses start cooling when the sun's forcing stops. I accepted that the CO2 enriched glasshouse (Gh.8x) cools more slowly than the control (Gh.1x). But sometime before dawn the temperature and heat content of both glasshouses is the same, ie they both get to equilibrium with their (local) surroundings. Put an open-top thermos flask with warm water and a cup of same volume of warm water into a fridge and wait. The thermos will stay warm for longer but it won't be long before they are both the same temperature. So, the Gh.8x can only slow down the cooling briefly, but eventually comes into equilibrium with the ambient fridge air. Would you agree?

    I'm not questioning the existence of a greenhouse effect per se, but I am questioning whether a short period of less-than-normal overnight cooling is in fact "climate change", notwithstanding that "average" temps appear to be higher.

    I'm not sure why the experiment is invalid due to size alone, but let's assume that the Gh's are at least tall enough to intercept >99% of the intial LWR emitted from the surface (100m ?). The delayed outward radiation is real, but eventually the retained energy makes its way to the Gh walls/ceiling, and is transferred to outside the system.

    In the real world, the energy makes its way to TOA whether via convection or radiation) and ditto..is transferred to outside the system. "Climate change" (as opposed to simply increase in average temperature readings over time) requires that some of that energy stays in the system. Can you point me to anywhere that empirically demonstrates or explains why it takes more than a few hours on average, for the retained energy to make its way to TOA and get lost from the system?
  29. mullumhillbilly - The disproportionate amount of energy retained by GHG emissions versus combustion is because the GHG's retain solar energy (fusion), not just release a bit of chemical energy (combustion). By comparison to any amount of coal burnt, the sun is an essentially limitless energy input.

    A gift that just keeps on giving, unfortunately...

    I will note that Gedankenexperiments regarding greenhouses, glass plates, etc., have led a number of commenters astray - glass greenhouse analogies really don't capture the details of radiative physics and energy flows.
  30. KR@70 ...keeps on giving... What's till puzzling me is Flanner 2009 magnifying the original fire *100 every year with GHGs, where my calcs above (noting the corrected arithemetic to convert W->J) suggest magnifying the fires heat by just 1.5 with GHGs, and that only after CO2 has doubled (ie the original heat reproduced every 0.66 yrs). I suspect (not being able to access the original) that Flanners figure probaly includes the whole of GHG effect, not just the marginal AGW additions that I used. Either way, this is one amazing "eternal flame".

    So analogy good, Gedankenexperiment bad ? OK so you don't like the glasshouse, or the fridge. Well, could you perhaps address the questions anyway ? Maybe they are already dealt with elsewhere on this site, but its rather labyrinthine, and too voluminous to wade through all the comments (which dont get included in the search engine), and I havent found an answer with the search terms I used. So apologies if you feel your time is being wasted, but I am genuinely interested in finding an answer, not arguing from an entrenched position.

    Rather than two glasshouses, can you imagine two identical planets Earth.2x and Earth.1x ?

    On Earth.2x, the atmosphere with doubled load of GHG will slow down the rate of night cooling (heat loss) compared to that on Earth.1x. However in the absence of new forcings (the sun), the amount of heat energy held in Earth.2x atmosphere and oceans will eventually equal that on Earth 1.x. , and that would happen well above zero energy point on both planets. Would you agree with that in principle?

    If we can agree on that, the key question would be "how long is eventually ?" If its less than 12 hours, it seems to me that, nightwarming and rises in "average" temperature notwithstanding, there is nothing that constitutes "climate change", no residual energy to drive the cyclones, floods and ice melt.

    So can you point me to anywhere that empirically demonstrates or explains why it takes more than a few hours on average, for the obstructed/trapped/retained energy to make its way to TOA and get lost from the system?
  31. mullumhillbilly

    Thought experiments and analogies both have their issues - they are fine as long as the points being discussed actually map to the system under discussion, but have a tendency for irrelevant aspects of the analogy to be taken as part of the mapped system.

    The core of what happens with the greenhouse effect is directly tied to conservation of energy - the amount of energy entering a system (a dynamic system like the Earth climate) must equal the amount leaving the system, or the amount of energy in the system will change.

    Now, you can look at the Earth as a simple, zero degree system - increases in GHG's effectively reduce the emissivity (amount of energy the Earth radiates to space at any particular temperature), which means to match incoming solar energy the Earth must warm to a higher temperature before matching that with outgoing energy.

    In more detail, increasing GHG's raise the level in the atmosphere where infrared radiation can emit to space - and given the lapse rate of the atmosphere, those are colder regions, meaning again less energy going to space, and an imbalance between incoming/outgoing. The Earth warms, the entire atmosphere warms, and then that level where radiation can escape is warm enough to again balance the equations.

    It's not a matter of "energy taking more hours to leave", it's a matter of how fast energy can leave, based upon the physical radiative characteristics of the Earth.

    In terms of simple analogies, I like to think of the Earth as a bucket in a waterfall. Energy comes in, overflows the edges, and goes out - increased GHG's raise the side of the bucket, the water/energy level must get higher to flow out at the rate it's coming in.

    (Moderators - previous comment was in error, due to my fumblefingeredly hitting the wrong button; could you delete that?)
  32. KR@81 >It's not a matter of "energy taking more hours to leave", it's a matter of how fast energy can leave.

    So "fast" has nothing to do with time? I agree there is near-ground early-evening warming, and I think I understand the essentials of the emissivity picture, S-B & T^4 etc, but the clock is still a factor. If the heat energy is not accumulating daily (on average at the rate of 100:1 GHG energy:combustion energy if you agree with Flanner 2009), then climate sensitivity is not as high as you think it is.

    Raising the edge of the bucket in a waterfall is not a good analogy because you are talking about continuous flow, whereas GHG only operate to trap (delay) the flow when the sun is not shining.
    Response:

    [DB] "whereas GHG only operate to trap (delay) the flow when the sun is not shining"

    You are considerably in error on this; GHG's do their thing 24/7/365, rain/shine/by dark of night.

  33. mullumhillbilly#82: "GHG only operate to trap (delay) the flow when the sun is not shining. "

    Really? Doesn't the warming surface radiate IR during the daytime? If not, why not? How do the GHG molecules know what time of day it is?
  34. mullumhillbilly - The only way for energy to leave the Earth climate is as thermal radiation. All else is just re-arrangements of the energy within the climate.

    Thermal radiation leaves any object at a rate determined by (a) temperature, and (b) the ability of the surface to radiate at that temperature. Please see this Thermal Radiation wiki for an overview.

    Without GHG's, the surface of the Earth radiating at an emissivity of 0.98 (98% of theoretic max efficiency, as dirt and water are very effective emitters of IR) would be able to match incoming energy at a temperature of ~255K, or -18C. That would be cold.

    GHG's absorb IR, re-radiate a great deal back to the surface, and most importantly, as GHG concentrations increase, the effective level in the atmosphere where IR can escape is higher and (due to the lapse rate) colder. Therefore less IR escapes at GHG frequencies at any particular temperature. In order to radiate as much energy as is incoming, the Earth has to be warmer.

    See the following:



    The smooth curve shows what a 'blackbody' could emit. The notches are where GHG's reduce radiation at any particular temperature.

    In order to radiate the same energy as the blackbody, the integrated area of the jagged curve must match the area of the smooth one, and hence the entire curve must be higher - the temperature of the emitting body (in this case the Earth) must be higher to scale it up. In this case, as observed, about 15C. Then outgoing matches incoming energy.

    ---

    If this is not comprehensible, I strongly suggest doing some reading on the basics of the radiative greenhouse effect. There's tons of information out there for you.
  35. DB82, muonc83, OK that was an oversimplification, but my essential point stands I think. GHG are working around the clock but daytime incoming radiation far outweighs any interception of surface FIR, so most of the GHG warming of the atmosphere happens at night. On the bright side of the moon surface temps are +100C, dark side -150C. Are you telling me GHGs make the planet warmer during daytime?
    Response:

    [DB] "Are you telling me GHGs make the planet warmer during daytime?"

    Think about what you are implying (that molecules somehow "know" what the time of day is).

    GHG molecules do their thing 24/7/365.

    Like the Terminator, they just...don't...stop...

  36. Consider putting a thermometer in a vacuum in the shade on a sunny day. Do you expect the reading to plummet to sub-zero? Consider doing the same experiment on the moon.

    Look at the actual measurement of DLR (eg here) and note that DLR strongest in day as you would expect. Your daytime warmth is from both the sun directly and DLR.
  37. mullumhillbilly @85, it is true that the diurnal (day/night) difference between warming due to insolation is far greater than the diurnal difference in warming due to GHG. But the GHG cause more warming during the day than during the night.

    The primary reason the earth has such a small diurnal range compared the the moon is the presence of a liquid ocean which requires the storage or release of very large amounts of energy to heat or cool, thus keeping temperatures relatively constant. The atmosphere, particularly when humid, has a similar but smaller effect. That is quite distinct from the GHE.
  38. KR84, Yes GHGs_101 is quite comprehensible thank you, but this really doesn't address the question of time. So less FIR (LWR) escapes to begin with at night, but the surface cools rapidly as the night goes on (frost) and the IR drops well before dawn. Diurnal variation of IR is not a new idea. I'm saying time is important, and you glossed over that. Climate sensitivity is very much dependent on how much of the trapped/delayed IR-sourced energy makes its way to TOA by dawn (incl by convection), and thence is lost to space.
  39. scaddenp@86 ?? DLR is highest at night in your diagrams, except for a couple of early afternoon peaks when presumably some clouds passed over.

    Thermometer in the shade. If it truly was totally insulated from any external energy, of course it would drop to zero, whether on the Moon or on Venus. What's your point?
  40. tomCurtis@87. So you are saying humidity and water vapour are NOT part of the GHE?

    I agree re buffering capacity of oceans, thence maritime climate cf inland deserts, and I was simply using the Moon example to illustrate the overwhelming warming effect of direct insolation vs GHGs.

    You say "GHGs cause more warming during the day than during the night". Presumably you mean the net effect is significant. (net being gross "trapping" minus emission back to space). Is the surface temperature record reliable enough to show this? As I understand it, most (if not all) of the demonstrated warming has been at night in higher latitudes. I don't think we have the information to say whether that night warming (eg is it based on higher minimum temps, or an integral of degree-hours?) actually reperesents retention of energy in the system. I've already suggested how higher night temps can occur without net gain of energy in a 24 hour cycle.

    I'm not even disputing that there may be some residual energy accumulating, but the actual amount is crucial to climate sensitivity.
  41. mullumhillbilly - A quick search on your moniker indicates that you have been posting on climate topics for a while, complete with heavy use of the term "warmist".

    I'm not interested in recapitulating the entire greenhouse gas theory to someone who should know it by this point. I would suggest reading through the Science of Doom greenhouse effect pages, then returning if you still have any questions. GHG's warm the climate both night and day, reducing the diurnal temperature variations by reducing the climates ability to dump heat quickly.

    At the moment you are giving me a very strong impression of being disingenuous, of arguing for the sake of arguing, and of raising silly objections. Just not worth my while...
  42. I am pointing out DLR is operating significantly in day time. Your timing argument makes no sense to me. At climate scale, you are looking at annual averages. You think models are based on calculations for a particular time of the day?
  43. mullumhillbilly#91: "most (if not all) of the demonstrated warming has been at night in higher latitudes"

    It's high time you started doing as most others here do: Substantiate your statements. By no means is all of the observed warming at night, nor is it all in the higher latitudes. You might want to look up 'arctic amplification' and 'diurnal temperature range' for some conceptual support.

    "suggested how higher night temps can occur without net gain of energy in a 24 hour cycle. "

    Your 'suggestions' don't carry much weight by themselves. Has anyone doing research in the climate sciences made a similar suggestion? If so, don't you owe that researcher the credit?

    Although KR kindly provided the sound basis for the greenhouse effect, that is not the topic on this thread. This thread is about waste heat. Thus far, you've shown nothing (other than your initial calculation errors) to counter the position of the original post: Waste heat is insignificant compared to greenhouse radiative forcing. If you have any evidence to the contrary, please feel free to share. If you have no evidence, continued speculation is not particularly interesting.
  44. mullumhillbilly @91 I never said anything like the claim that water vapour is not part of the greenhouse effect, and I resent your attempt to put words in my mouth.

    The specific heat capacity of gaseous H2O is approximately twice that of dry air. That means that if you increase the humidity, you increase the energy required to raise the temperature of air; and increase the energy in the air that needs to dissipate when cooling. That is an additional effect to the greenhouse effect of the water vapour.

    Let me add that your whole angle of attack here, in addition to being dreadfully uninformed, is entirely wrong headed. The rate at which the GHE warms the planet is a function of the energy difference between the planets current OLR and that required for equilibrium. If the planet is cooler, that difference is greater and the planet warms faster.

    Given that, and assume contrary to fact that the energy accumulated during the day was entirely dissipated at night. In that case, during the day time a planet with GHE will warm much faster than a planet without GHE. Hence, even if you could prove your core assumption, your conclusions would not follow.

    As it happens, your main assumption is grossly in error as I showed in 77. Your hand waving response was simply irrelevant. Given the absence of renewed insolation, the surface of the Earth would cool to less than -208 degrees K over time, but during the entire duration of that cooling, it would cool slower with a GHE than without it.

    You assume my argument is irrelevant because at some time (generally after 12 hours) another source of heat arrives, reversing the slowing. That reversal is, of course, the onset of daylight. It follows that if the planet with a GHE cools slower than one without until the onset of daylight, or more typically, a breeze carrying heat from nearby day lit areas, then more of the heat of the preceding day is retained each day with a GHE, contrary to your supposition.

    What is more, having retained more heat from the preceding day, with the GHE the the surface will also warm faster during the day so that, by the end of the day, it will have more heat to retain over night.

    For an argument like yours to have any merit, the surface of the Earth would need to cool to the point where it is in equilibrium with geothermal energy each night, which obviously does not happen. For anybody guided by evidence, that means it has no more credibility than geocentrism (it is that obviously wrong).
  45. KR@90, sure I've ventured to comment elsewhere, and have even supported your scientifically-sound comments where others were attempting to argue the second law fallacy. So I'm not here with an agressive agenda, and like you I don't have time to waste in simply arguing. I'm looking for answers to some simple questions that don't seem to have been adequately addressed, the time factor is one of them. And BTW, to me, a "Warmist" is someone who believes that climate sensitivity is higher than empirical evidence suggests, who abusively "denies" all skeptical questions or alternative explanations, who thinks that the peer-review system is beyond reproach, and who adamantly asserts that mitigation not adapatation is the only answer. Not pointing that at you, I appreciate that you are polite and patient, although it seems I'm still not getting a direct answer about the time factor. You say "..the climates ability to dump heat quickly", which again is noting that time is of the essence.

    scaddenp@92 I think I'm repeating myself. DLR is far less important during the day than at night, in relation to the planetary energy sum that drives climate. The yearly average is obviously an integral of daily balances, and climate sensitivity to CO2 arises from the net accumulation of atmospheric heat energy over time, for two atmospheres with differing CO2. That net accumulation seems to be predominantly at night, because that's when elevated CO2 "trapping" of FIR-LWR has greater releative significance. Elevated CO2 is not so important to climate warming during the day because SWR heating is by far predominant. What's your explanation for why DLR is less during daylight hours, peaks at ~midnight, then declines until dawn ?

    If the accumulation of energy over time is less than thought because pre-dawn energy losses are greater than thought, then climate sensitivity is lower than thought. I don't have any references to back that up just now, but then neither have I seen any empirical analysis of diurnal energy balance with differing CO2 concs.

    TomC@94. You said "The atmosphere, particularly when humid, has a similar but smaller effect. That is quite distinct from the GHE". OK, I guess I was nitpicking at you in the way others were doing to me, I'm sure you understand the effects of water vapour. "...entire duration of that cooling, it would cool slower with a GHE than without it." I don't doubt that, but on a timescale of a ~12 hour night, with soil and rock being pretty good insulators, the crucial thing is the LWR from exposed surfaces, no? eg Surface temps can be sub-zero C, but just a few cm into the soil it might be 10 deg warmer. Is there any LWR coming from the subsoil? Of course not. And if the amount of escaping LWR drops markedly after midnight (as scaddennp's link in 86 shows), then higher CO2 levels won't be "trapping" much extra energy at that time. So, I'm agreeing that a planet with GHE is warmer than one without; its strawman argument to suggest otherwise. What you dont seem to be addressing is my point that a rise in GHG might not cause the marked increase in GHE if overnight energy losses are greater than thought. Where is the "missing heat" ? Regarding "...equilibrium with geothermal energy" , that's nothing like what I'm saying, and another strawman.

    muonC@93. I offered to take these to another thread, but didnt get a suggestion. Feel free to transfer them if you like (but leave a link please so I can find it again).

    Waste heat.. yes I came to the conclusion (with appreciation for TomC@71 correcting my units conversion error) that, if (I.F.F.) CO2 doubling leads to 3.7W/m2 forcing, then GHG forcing energy is equal to combustion heat every 8 months (0.66 yrs, or factor 1.5x). Even that sounded too high, which is why I raised the overnight heat loss question. I'm still in a state of disbelief that GHG forcing can be 100x the combustion energy, every year, and will look into it further when time permits and I can find somewhere to acces Flanner's full paper.
    Response:

    [DB] Try here. 

    The cost of 1 GRL article:  $25

    The power of Google:  priceless.

  46. Fuel + Oxygen --> Heat + Water + carbon dioxide.

    more combustion will bring about more production of heat and CO2.

    Decrease the rate of combustion, and you will decrease the amount of heat released, and reduce the rate of warming of air.

    The heating effect of the sun is a constant, and will always be there no matter what you do, whereas the burning of fuel is a variable.

    It is clearly heat which warms up the surrounding air, not CO2.

    Does reducing CO2 concentration decreases the amount of energy generated from bond breaking of the fuel?

    An analogy will be that of taking the elevator. When a single person takes a ride in the elevator, he is producing CO2 and radiating body heat via IR. This excess heat introduced to the atmosphere within the elevator is removed easily by the ventilation fan, which draws out heat at a constant rate. (Similar to heat dissipating heat out to space.

    Ever been in a crowded elevator? When you increase the number of occupants inside the elevator, more people equates to more radiation of body heat, and more emission of CO2,(analogous to increased combustion of fossil fuel), and the ventilation are unable to ventilate the elevator as efficiency.
    You can place a vat of CaOH to remove all the CO2 in the air, but the elevator will still remain hot and stuffy.

    Since CO2 is a byproduct of heat liberation, it should be perceived as an indicator of warming, rather than a causative agent of warming.
    I agree that CO2 is a GHG, but its effects are overrated.
    If you think that an increase in a slight percentage of atmospheric concentration of CO2 can bring about climate change (despite the doubling, it is still at around 0.3% atmospheric concentration, remaining more or less constant), then why not the idea that the small amount of AWH generated can actually be a more important factor in causing warming than CO2?

    And if you want to argue about greenhouse gases being responsible for drastic warming, why is everyone ignoring the presence of the 80% atmospheric concentration of nitrogen, which is also a greenhouse gas? Should 80% of a greenhouse gas be more significant than 0.3% of greenhouse gas? Compared to nitrogen, the decimal percentage increase of CO2 can be regarded as negligible.

    In the previous thread, people have been likening AWH to a cracker and GHG as icecreams, and their effect on weight gain. It is important to realise that what actually brings about a change is the presence of a non-constant factor.

    If your staple food consist of eating 2200 calories of icecream daily, without any gain in weight, and put on weight only after eating a 50calorie cracker, it is actually the cracker which causes the weight gain, as it is a deviation from the existing equilibrium.

    The output of the sun has been more or less constant, while man's energy consumption has been increasing steadily, and shouldn't the warming be attributed to this rise in energy consumption?

    Referring to another analogy on this thread, while a candle may not hit up the room fast enough, a furnace may.
    Man's energy consumption has grown from a "candle" into a "furnace", and it is this massive increase in energy liberation that accounts for the drastic rise in temperature of the room, which remains as a constant, not changing in its dimensions.

    And lastly, the example of a nuclear plant is a highly relevant and interesting one. If CO2 is responsible for warming, why does nuclear plants, which does not produce CO2, still emits waste heat that serves to heat up the surrounding air?

    The only way to reduce warming, is to increase energy efficiency, so that less energy is wasted for the unintentional heating of air.
  47. Donthc@96

    To engage constructively here one is required to provide evidence for one's claims.

    Amongst many other things in your "thesis" that are without foundation the most obvious is:

    Nitrogen is not a greenhouse gas...try wikipedia for "greenhouse gas".

    (this site has a lot of work to do... it's like sweeping grains of supposition off a beach of ignorance)
  48. Donthc, the papers cited in this thread quantify waste heat and find it 100 times too small. If you want to argue that this quantity is in error you have to provide some evidence, not just an opinion. What calculations are you relying on?

    Nitrogen a GH gas? That's a good one. What else do you have in store?

    This makes no sense whatsoever: "If CO2 is responsible for warming, why does nuclear plants, which does not produce CO2, still emits waste heat that serves to heat up the surrounding air?"
    How could the radiative warming from GH gases prevent the waste heat from cooling towers to be dissipated? Why would these 2 processes be mutually exclusive? There is absolutely no reason, unless you have some new funky laws of physics up your sleeve.
  49. Donthc, others have commented on some of the fundamental errors in your analysis, but there was a particularly odd one which hasn't been remarked on yet;

    "The heating effect of the sun is a constant..."

    Right. Constant. Other than... variable levels of clouds blocking it, different surface albedo conditions reflecting it, changes in the intensity of the greenhouse effect, that whole 'day and night' thing, progression of the seasons, orbital variations (c.f. 'Milankovitch cycles'), the ~11 year solar cycle, other variations in solar output such as the Maunder minimum, the fact that the Sun is now about 30% 'hotter' than it was in the Earth's early history, et cetera.

    You could accurately say, 'the average annual heating effect of the Sun is currently showing only small variations on a multi-decadal scale'... but no, it is nothing like 'constant'.
  50. jmorpus has been disrailing the discussion of a new tool to handle clouds in climate models. His discussion has been inchoate, so until muoncounter and oneiota linked to websites expousing similar views, I did not know where jmorpuss was going, only that he was trampling the evidence in the dirt to get there. Having a better idea now, I now recognise jmorpuss' claims as a variant of the claim that global warming is caused by waste heat, hence my response here.

    The websites linked to by muoncounter and oneiota are very explicit. According to them, global warming is caused by heat generated by the absorption of radio waves from humanities many radio transmissions. Of course, human energy emissions as radio waves is a very small subset of total human energy usage. Therefore total power emissions as radiowaves is a very small fraction of the 0.028 W/m^2 waste heat by humans as calculated by Flanner, and hence an even smaller percent of the 2.9 W/m^2 GHG forcing as indicated in the article above.

    This is an insurmountable barrier to such theories.

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