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Waste heat vs greenhouse warming

Posted on 27 July 2010 by John Cook

A vigorous discussion has erupted on the waste heat page. Problem is, there's not meant to be a waste heat page! As I encounter new skeptic arguments, I add them to the to-do list and gradually (very gradually) research the peer-reviewed literature then write an explanation of what the science says, usually in order of popularity. I hadn't got around to looking into the issue of waste heat. Nevertheless, one intrepid Skeptical Science user found the empty page waiting to be populated and began a discussion there (j'accuse Doug Bostrom). So let's look at waste heat...

Firstly, what is waste heat? 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 do 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.

UPDATE 27 July: there is some confusion about the term 'waste heat'. Here, what I'm talking about is all the heat generated by energy use. When humans generate energy, much of it is immediately dissipated as heat. The rest is converted to electricity or energy of some sort (eg - mechanical, chemical, etc). But even this energy eventually dissipates as heat into the environment. So yes, 'waste heat' is not an ideal term. Flanner uses the term "anthropogenic heat flux".

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Comments 301 to 350 out of 431:

  1. archiesteel You keep insisting I produce a map and that I claim something about maps existing, etc. Someone's imagination definitely got sparked and related the word "map" to satellite surface imagery. Actually if you take a look at the center image above, you will notice the contours indicating temperatures actually are asymetrical around city center, with warmer temperatures downwind. I'm sure real estate agents would be thrilled have the kind of control on physics that you purport so that they could indeed command hot air to blow straight up around houses they cant sell. Again, your insistence in all this is just a way to detract from the topic at hand which looks like your best shot. Congradulations! You are king of the hill.
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  2. RSVP - If you want to know the theoretic energy use that (with no GHG production) would raise global temps by 1.0°C, just turn the equation around: dT / λ = dF That's why I like giving the appropriate equations - you could have done this yourself. Averaging λ to be 0.87, dF = 1.15 W/m^2. Current forcing with an energy use of 15 TW is 0.028 W/m^2. Therefore to reach 1.15 W/m^2 and 1.0°C of energy change we would need to use 41x our current energy, or 615 TW. With the range of climate sensitivity going from 0.54 to 1.2, that might range from 0.62°C to 1.38°C, but it's a mid-range estimate. Hmmm - I don't need any lakes boiled at the moment... But to return to the topic of this thread - Waste Heat is not responsible for the current warming (0.8°C and nowhere near equilibrium); it might at equilibrium add 0.015°C to 0.034°C.
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  3. RSVP - It really appears to me that you are being argumentative rather than arguing. I have read this entire thread and am still unclear what it is you are trying to say. @300 - "Actually if you take a look at the center image above, you will notice the contours indicating temperatures actually are asymetrical around city center, with warmer temperatures downwind." Two problems with this claim. Cities are asymmetrical and the map does not include any wind information from which to draw your conclusion.
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  4. @RSVP: "You keep insisting I produce a map and that I claim something about maps existing" I didn't ask for a map, I asked for the map-like projection you mentioned. You know, like when you said: "So instead of the effect you describe, as seen from a map, there is typically a large smudge or plume that emerges around an urban center that tapers eastward... heat that is gradually dispersed but never lost" I want to see you post an example that clearly illustrates what you claim. And no, the middle image above doesn't count, as it does not include city limit, and it seems to be an averaged measurement. You also don't have wind patterns indicated. I'm still waiting. "Again, your insistence in all this is just a way to detract from the topic at hand" No, I'm just trying to keep you accountable, which you are trying to avoid by any means necessary. "Congradulations! You are king of the hill." Sorry, but you lost the debate days ago. You're just trying to squirm your way out of it, and it's kind of sad to watch.
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  5. #300: "command hot air to blow straight up" Here's a graphic illustration that all this waste heat discussion is just so much hot air: The 1320 MW power plant Joliet 29 is shown as the light blue cluster in the upper left-center in the upper image (visible and NIR); the waste heat, both from its structures and its cooling pond, are shown as white-red in the lower (ASTER) thermal image. Within the confines of the pond, the false-color IR has gone back to green, which is only slightly warmer than the heat signature of the nearby environment. Also note this plant's CO2 emissions in 2006: 6.5 Megatons. Unlike this waste heat and all the hot air it has generated here, that CO2 is still out there.
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  6. @muoncounter: thanks for this convincing demonstration.
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  7. archiesteel #303 "I want to see you post an example that clearly illustrates what you claim" As I was saying earlier RSVP #292 "...if it isnt found on the internet, it cant be true." muoncounter #304 "1320 MW" Since ALL that energy is going straight up, lets just hope the IR detector has some major filters in place.
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  8. pbjamm #302 "It really appears to me that you are being argumentative rather than arguing." Well it's a shame it appears that way, but I am being asked to justify things that to me are fairly obvious. For instance, there are those that would just as well hang out downwind from a forest fire than upwind, or assume the plume of ash and gases from Iceland that stretched all the way to the Baltic, (now maybe it was just only Scotland, very sorry), contained no latent heat whatsoever, etc. What is more of a shame is the distraction from the real discussion, especially what appears to be pure provocation, that is best ignored, although it can be difficult.
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  9. KR #301 Thanks for the answer.
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  10. @RSVP: "What is more of a shame is the distraction from the real discussion, especially what appears to be pure provocation" So why do you keep generating such distractions? Why do you keep posting messages that basically amount to flamebaiting (an aggressive form of provocation)? "that is best ignored, although it can be difficult." Well, that is true. We should ignore your attempts at provocation, but that *is* difficult. The point is that anthropogenic waste heat represents 1% of anthropogenic greenhouse warming. No amount of snide remarks and strawman arguments from you (i.e. standing downwind from a forest fire) will change this.
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  11. An interesting thing to consider would be, what if we'd thoroughly cracked fusion energy and were effortlessly liberating something like 3X the energy KR describes in his comment at 301, energy being finally "too cheap to meter," with demand escalating rapidly to spawn even higher levels of dumped energy? Now picture what would happen if one were to try to build a scientific case suggesting that all of that heat would only leave the planet once the planet had warmed to a new rough equilibrium temperature, that increasing demand would drive that "rest temperature" upward still further. Would any model be good enough to overcome opposition to ending the big party? For my part I've a feeling we'd be seeing a close analog to the present argument over CO2, employing many of the same objections.
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  12. Doug #310: If we had that kind of 'limitless' energy then we would be able to put massive solar arrays in space and on the bright side of the moon... which could also provide effectively 'limitless' energy. The difference between a 'waste heat' forcing and a 'greenhouse heat' forcing is that the minute you turned off the fusion reactors the forcing would begin to decline rapidly... they would only cause warming so long as they were running. Carbon dioxide, on the other hand, would stay in the atmosphere and continue causing elevated temperatures for centuries. It's questionable whether we'd even be able to get up to 100x our current industrial production / waste heat and thus match CURRENT CO2 warming (let alone future CO2 warming). But if we somehow did find a way to generate that much energy the things we could accomplish would make it unnecessary to produce the waste heat. In any case, the hypothetical is centuries away, could not possibly be achieved with fossil fuels (there aren't enough of them) and would take place in a world with technologies radically different than current. In short, too far afield to possible predict. By then we might have perfected infrared rectifying antennas and be turning 'waste heat' itself into electricity.
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  13. I realize all that, CB, it's a thought experiment. Point is, it's not really science we're arguing about here, but other stuff. Money (or more particularly who gets it), lifestyle, that sort of thing. If something other than CO2 was the issue, we'd see roughly the same array of tactics employed to avoid dealing w/the obvious.
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  14. BTW, it's definitely off-topic here but the orbiting "solar array in space" concept has another issue w/waste heat, namely how to get rid of energy lost through transmission inefficiency. Running the numbers on microwave transmission, for instance, even with a unreasonably good efficiency any useful system would have to radiate enormous quantities of heat. Structure and mechanism to deal w/that thermal problem would seem to make the physics and economics of the whole matter even more difficult, maybe intractable. Putting arrays on the moon would make the radiator mass issue moot but would seem to be pointless as the moon has the same diurnal problem as Earth but even worse, night being much longer.
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  15. CBDunkerson #311 "By then we might have perfected infrared rectifying antennas and be turning 'waste heat' itself into electricity." ...electricity that in turn produces heat, which generates IR, which generates electricity.... you could call it the Perpetual Motion Heat Diode Energy Saver, patent pending.
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  16. #311 Sorry, I missed an important nuance of your idea for recycling energy, and that is you only wanted to recycle waste heat. What about all that excess heat from GHGs? Whos side are you on anyway?
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  17. @RSVP: "...electricity that in turn produces heat, which generates IR, which generates electricity.... you could call it the Perpetual Motion Heat Diode Energy Saver, patent pending." You seem to miss the point that it's "waste" heat. The amount wasted being less than the amount recycled...well, you can figure out the rest. Hopefully. "Sorry, I missed an important nuance of your idea for recycling energy, and that is you only wanted to recycle waste heat." Nowhere did I read that CBD wanted to only recycle waste heat. You're really grasping at straws, now. It seems as though you're not even trying anymore.
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  18. KR #301 "...you could have done this yourself" Would you have used my formula? I doubt it. At any rate, it appears you do agree there is something going on here as you say "waste heat... might at equilibrium add 0.015°C to 0.034°C. ". Before assuming losses, why not first determine how this waste heat might raise temperature? If the volume of air is assumed, 4.2 billion cubic kilometers, according to http://wiki.answers.com/Q/What_is_the_volume_of_Earth's_atmosphere air´s heat capacity cp = 1.0 kJ/kg C, according to... http://www.engineeringtoolbox.com/air-specific-heat-capacity-d_705.html the mass of air, roughly 1.2 kg/m3 @ 15 C, according to http://ballonsolaire.pagesperso-orange.fr/en-theorie1.htm and the amount of waste heat per year is around 474 x 10E18 J according to the link you provide above,...calculating.. 4.2x10E9 km3 = 4.2x10E18 m3, whih yeilds 5x10E18 kg, multiply by cp (10E3 J/kgC), you get 5x10E21 J/C, which means it takes that much energy to raise the atmosphere temp 1 degree C. That seems like a lot of energy to me. But according to the link you provided, the amount of waste heat per year is 474 x 10E21 J. Taking this value .474x10E21 J and dividing by the amount of energy required as calculated above (5x10E21 J/C) We get 0.0948 C. Rounding up, that's 0.1 C per year. If one assumes all of this energy is lost to space, then all of global warming is likely due to GHGs. But since AGW assumes the ability of the atmosphere to radiate energy is getting worse as time goes on, it has to be assumed that some portion of this energy is not escaping, and is therefore accumulating. Assuming (just for grins) only a tenth of this energy is retained. This would yeild a .01 C increase each year. After on century you get an increase of 1 C. But 1 or 2 degrees C is roughly what GHG are supposedly adding to global temperatures over the next century in the best of circumstances, and perhaps more in the worst of circumstances, which could have also been achieved by assuming just a little more waste heat being retained. Concluding... it looks like ignoring waste heat is literally "playing with fire". But that is just a skeptic talking.
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  19. RSVP #317 Woops. Sorry, there is a typo, 474 x 10E21 J, where the exponent should be 18. This doesnt affect the calculation.
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  20. #317: "the amount of waste heat per year is around 474 x 10E18 J according to the link you provide above," You seem to equate all energy use with 'waste heat', using the 474e18 J given in said link as if none of that heat went to heat water or heat solids. I wonder why no one else does it this way. For example, a very thorough study of the US industrial processes concluded that of the 32e15 BTU (34e18 J) consumed in 2008 by US industry, "as much as 20 to 50% of the energy consumed is ultimately lost via waste heat contained in streams of hot exhaust gases and liquids, as well as through heat conduction, convection, and radiation from hot equipment surfaces and from heated product streams While industry uses only about one third of the total US energy consumption and the US is only a fraction of the entire world's energy consumption, there's a long way between 34x10^18 J and the 474x10^18 J you've used.
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  21. muoncounter #319 In your reference "as much as 20 to 50% of the energy consumed is ultimately lost via waste heat " the use of waste heat in this context refers to inefficiencies in systems. It refers to energy expenditure that accomplishes no useful work. My use of the term refers to any and all heat that is imparted on any and all things on this Earth, assuming the first law of thermodynamics holds for fossil fuel consumption, which it does.... (just imagine if it didnt... we'd have a huge class action law suit for that energy weve been charged for!) So all this energy could be the heat produced from friction on tires, air, engine parts. This could be heat that ultimately escapes from homes for heating. This could be heat used to warm water to shower, all of it ultimately ending up in the environment. I assumed the atmosphere just to simplify the problem, and you are right about heat getting into streams, the oceans etc. You can complicate and refine this as much as you want, and of course this was very rough. For instance, I assume the mass of air is constant with altitude, whereas in reality it drops off to about half at 27,000 ft, which when accounted for would make the resulting temperature rise even higher. Someone else will say the atmosphere is higher, so the rise is less, and on and on. I am aware of this, but if you assume the Earth´s temperature will rise 3 degrees in the next 100 years due to GHGs, then each year the change is 0.03 C. Here, the result for "waste heat" could be 0.1 C. So the only way it could be GHG is if all the waste heat magically goes away, which is what the "non contrarians" are going to have to say.
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  22. RSVP, All heat imparted from our technology is by definition "waste". All of it. The heat which comes from friction, A/C, factories and electronics is all due to inefficiency. Your assumption that waste heat is enough to warm the planet by 0.1C per year is based on a faulty premise. Nor have you demonstrated the effect of "waste heat" is more than the +0.028 W m−2 identified by Flannery. If you have identified a flaw in his paper, please point it out to us.
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  23. @RSVP: AWH represents about 1% of AGHW. Therefore, about 1% of the temperature incraease is due to waste heat. Why are you still arguing about this (apart from wasting peopel's time, which I suspect is your true objective here)?
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  24. Speaking of IR antennas or at least something in the same domain of recovering wasted heat energy, thermionic junctions are finally showing some promise for recycling of waste heat on a large scale. More nanotech goodness...
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  25. RSVP - I have to admit, reading this post of yours made me laugh. Raising the temperature 0.015°C to 0.034°C is sufficient to radiate 15 TW/year to space (i.e., all of the anthropogenic heat flux), balancing the energies involved. At that point the Earth stops warming from AHF. And that warming is lost in the noise of the GHG driven temperature rise. Again, and (I'll try, really), my last post on this. Waste heat/AHF is 1% the energies of greenhouse gas entrapment (0.028 W/m^2 versus 2.9 W/m^2), and is therefore not the dominant cause of global warming. This skeptic argument is busted.
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  26. #320: "My use of the term refers to any and all heat that is imparted on any and all things on this Earth, assuming the first law of thermodynamics holds for fossil fuel consumption, which it does" Let's not be too hard on good ol' RSVP. In one post, he has tacitly endorsed: - warming is real (and thus - temperature record is reliable) - human effects are significant and causing the change (consuming fossil fuels liberates detectable heat) And simultaneously rejected the corresponding skeptic arguments (mainly 'its cooling'), but also some of the peripheral ones (if its anthropogenic, it's not 'the sun' nor 'cosmic rays' nor 'AMO/PDO/ENSO'). Probably a few more. All in all, I'd say RSVP is coming around. Of course,RSVP's basic premise may be tested by a simple experiment: if the energy consumed each year is directly reflected in atmospheric warming, we should be able to known match dips in historic energy consumption during recessions one-to-one with cooling episodes. For example, we've been in recession and thus it must have been cooler during this summer.
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  27. KR #324 "Raising the temperature 0.015°C to 0.034°C is sufficient to radiate 15 TW/year to space (i.e., all of the anthropogenic heat flux), " I understand the theory as modeled by a solid blackbody the size of the Earth. Or am I wrong about that too? Perhaps you could clarify whether you are referring to raising the temperature of the Earth's surface or its soupy atmosphere? I assume you mean the surface since you are saying that "the temperature" is actually being raised. (Or the third option: The hypothetical raising of temperature. But please lets not go there, unless it is absolutely essential to further delay enlightenment.) As far as dT / λ = dF. I am sure the equation is useful, but lambda most likely needs to be adjusted to account for whats really happening. I get the sense as applied to the effects of GHGs that its value reflects the assumption that GHG are the main cause of the observed global warming and in this sense the operation is basically both subjective and circular. muoncounter #325 "RSVP is coming around" Not sure why you say this? In #317, using published data and applying simple calculations, I have provided a conservative estimate that shows we are dumping enough energy in the environment to raise the atmosphere .1 degree C every year, which is 100 times the "forcing" that is attributed to GHGs, which essentially inverts the debate in terms of numerics. There is no waste heat sunset. It keeps on trucking night and day, year after year.
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  28. You've earlier acknowledged that anthropogenic heat radiated away from the planet. You are again claiming that it never leaves the planet. Why doesn't solar heat?
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  29. Bibliovermis #327 If the atmosphere were to always radiate more and more in a way that exactly compensated any positive changes in heat, global warming wouldnt be possible, no matter what the source. Waste heat is warming the air and in general convectively. This does not make the best launchpad for radiation.
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  30. RSVP - "I understand the theory as modeled by a solid blackbody the size of the Earth": Not quite what I said, and that's worth clarifying. The Earth is a 'graybody', not a blackbody, with notches in the emission spectra from among other influences greenhouse gases. Radiated energy increases as the 4th power of temperature, scaled by the emission spectra of the body in question. Graybodies never emit as efficiently as theoretic blackbodies, but they certainly do emit. Starting from a rough equilibrium, with the Earth radiating the energy it absorbs from the sun (known value) at current temps, an average increase of 0.015°C to 0.034°C emits an additional 15 TW/year (plus climate sensitivity scaled feedbacks) to space, thus reaching a new state of equilibrium between energy in/energy out. And once equilibrium is reached the system ceases to change due to that forcing. The "λ" in the sensitivity equation is exactly that - sensitivity to energy perturbations. This ranges from a low pushed by some sceptics (Lindzen and Choi, for example), to fairly high values given by loosely bounded upper limits. See Figure 4 of "How sensitive is our climate" to see a good discussion of this range. So no, "I get the sense as applied to the effects of GHGs that its value reflects the assumption that GHG are the main cause of the observed global warming and in this sense the operation is basically both subjective and circular" is incorrect. This is sensitivity to any forcing that adds energy to the climate system, which is why it applies to TSI variations, aerosols, GHG's, ice albedo, etc. Oh, and to anthropogenic heat flux...
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  31. RSVP - "If the atmosphere were to always radiate more and more in a way that exactly compensated any positive changes in heat, global warming wouldnt be possible" Incorrect. The Earth doesn't radiate more unless it warms, thus positive energy changes cause global warming. Cause >> effect: Positive energy changes >> global warming >> increased radiation >> steady state Claiming that this relationship disproves global warming is utter nonsense.
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  32. #326: "Not sure why you say this?" In order for your argument at 317 to work at all, you must accept the points (its warming, its not the sun, etc) made in 325. Like it or not, you're an AGW guy now. "There is no waste heat sunset." Nor is there a waste heat correlation. Your calculation says all energy consumed directly warms the atmosphere; temperature anomalies should correspond with historic energy consumption (see EIA energy consumption tables). You picked one year's energy consumption; over the longer term, how well do temperature anomalies track energy use? Your model makes a testable prediction. In order for your model to be taken seriously (although most others here have already said it should not), it still must be checked against observations. Sunrise, sunset.
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  33. KR #330 When you snap "incorrect" and "utter nonsense", it makes you appear insecure. If I am the one thats all messed up, you could be a little more magnanamous. I may be completely wrong, and if so, at least in being wrong, it would be just that much more proof that AGW is a good theory. You should be happy to proove me wrong, not upset. Besides, I am not sure what you have to worry about? There is still 20,000 experts out there that have signed on who would have to be convinced. AGW is an entrenched theory with a lot of backers. One might ask if it is even possible to disprove at this point, assuming it were completely flawed. Seriously, I am perfectly aware that "Radiated energy increases as the 4th power of temperature". What I find strange is how increased thermal radiation is used to undermine the contribution of waste heat, while the basis of GHG heating depends on jsut the opposite. Conclusion. Calm down, be happy. Besides, as far as every reading this, you are winning, (and won before the discussion even began given the rule set).
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  34. RSVP - No, not insecure, just tired of the same disproven skeptic arguments being brought up again and again.. oh look, and again. Increased thermal radiation affects the contributions of anthropogenic heat flux, and it affects the contributions of greenhouse gases. The same rules apply in all cases. Energy changes lead to temperature changes, and thence to radiation changes that tend to balance out the energy change. The 4th power of temperature relationship with energy is the negative feedback that limits temperature changes. However, GHG's are two orders of magnitude larger, and hence have a much larger effect. I'm quite frankly puzzled as to why you continue to think that AHF dominates global warming. Anthropogenic heat flux = 15 TW/year Greenhouse Gas entrapment = ~1550 TW/year Now, which of these will dominate climate effects?
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  35. muoncounter #331: "In order for your argument at 317 to work at all, you must accept the points (its warming, its not the sun, etc) made in 325." I dunno. I've yet to meet a dedicated 'skeptic' who isn't capable of passionately believing three or more contradictory things at the same time.
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  36. Why should we be happy about explaining, and re-explaining & then explaining yet again, basic, fundamental physical properties to somebody who adamantly insists that these misconceptions are the reason why a well-established field of scientific endeavor is composed of grossly incompetent, corrupt individuals? Yes, the scientific theory of anthropogenic warming can be disproven. Your lack of understanding and refusal to learn is not sufficient. We have been magnimous, but you are wrong - plain and simple. Your conceptions of how heat moves through the atmosphere are indeed utter nonsense. Indignation & insults (e.g. "you're just insecure") do not impart validity. Repeating the same misconception over & over & over is a good way to get people to snap at you. Global warming is how more & more energy is radiated from the planet. No additional energy can leave the system until there is an increase in temperature. The temperature cannot rise without more energy leaving the system. Energy can only leave the system through radiation; convection only moves it around internally. Energy cannot simultaneously cause a temperature increase & remain in the system (i.e. accumulate).
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  37. KR #333 "Anthropogenic heat flux = 15 TW/year" You mean 15 TW all year. Day and night. As there are 60 x 60 x 24 x 365.25 = 31536000 seconds in a year, that gives you 31536000 x 15 x 10E12 = 473040000 x 10E12 or 473 x 10E18 Joules. The heat flux value you cite for CO2 is an estimate, not a measurement; derived by correlating the observed warming with the observed CO2 increase and contrasting this with the known total solar heat flux. But the situation would be completely inverted, IF you started with the opposite assumption. So the only way you could be right about this is if you can prove that all that energy being injected into the environment is having no impact, (instead of warming things, it hightails for the stars). This is hard to believe as glaciers and polar caps melt before us.
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  38. RSVP > if the atmosphere were to always radiate more and more in a way that exactly compensated any positive changes in heat, global warming wouldnt be possible Seriously, I am perfectly aware that "Radiated energy increases as the 4th power of temperature" These two sentences are in direct contradiction to one another, and reflects your inability to accurately visualize the simple logic of how this would play out. If there is a positive change in the rate of heat input, then temperature will increase. If temperature increases, then radiated energy increases. As long as the output radiation is less than the input energy, then temperature will continue to increase, and just as you claim to be aware of, so will radiated energy. If temperature continues to increase, then output radiation will continue to increase, and if it does, it is mathematically and logically inevitable that eventually output will increase to a point where it matches input, at which point temperature increases will stop. If temperature increases stop, then so will changes in output, and since this is precisely the point where input matches output, there will be no more changes to the total energy content of the system. The overall temperature has gone up, but past this point there is no more accumulation.
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  39. RSVP - If you disagree with the level of CO2 forcings, I would suggest taking it to the How do we know more CO2 is causing warming thread; that's where it's appropriate. The value of 2.9 W/m^2 is quite well established from physical theory, from multiple orbital and ground measurements, etc.
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  40. Bibliovermis #335 "... a well-established field of scientific endeavor is composed of grossly incompetent, corrupt individuals" This is a good point, and we would all be better off assuming good will on all sides.
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  41. RSVP, back at 272 you wrote: "Imagine a lake whose level is seen to rise 3 inches in the course of 150 years due to a new spring breaking ground up stream." I couldn't "imagine" this because even the analogy breaks the laws of physics. So let's see if fixing it helps you see what we are saying. If a lake (i.e. the Earth's atmosphere) suddenly acquired a new source of incoming water (i.e. heat), such as the spring in your example (i.e. waste heat), it would NOT slowly increase in depth (i.e. temperature) over 150 years. The depth would increase almost immediately and then stop because the higher water level would allow more water to flow OUT of the lake as well. Once the new net outflow was equal to the new net inflow the new water level of the lake would then be set. How long the spring continues pouring in water is irrelevant... it doesn't lead to an ever increasing water level because when the inflow increases the outflow inherently must as well. Further, if the new inflow ever stopped or declined (i.e. we began producing less waste heat) the lake would quickly drop down to a lower level... the constant inflow is required just to MAINTAIN a small increase in the water level rather than producing a continually increasing level. Now, if you were to put sand bags blocking some of the streams leading out from the lake (i.e. decrease radiation outflow by increasing greenhouse gases) the lake would rise until the net outflow from the remaining streams, or possibly over the tops of the sandbags, again equaled the net inflow. The water level would then stay at that new height until the sandbags were removed. The inflow and outflow of water in a lake and energy in the atmosphere are pretty close corollaries... so long as you stick to actual physics for both.
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  42. CBDunkerson #340 You are correct about a lake with the topology you assume. In mine, the outflow is restricted through a narrow slot, and likely isnt too common in nature, but is possible. I should have said "dam", my bad. But now that you have taken up the point, it looks like there are two things to consider as far as the comparison with global warming. In the lake or dam, the rate of level change will depend on three things. How much water this new "spring" represents, the uptake capacity, and to what extent the outflow will increase as a result of an increase in height. This increase must be less than the source influx. This last factor seems to be key, and unless this is determined, I dont see how anyone can claim to be in a position of certainty. The question is really not whether it is accumulating. The question is how fast. All I am hearing is that radiation increases as the fourth power of temperature. If things were that simple, you wouldnt have to increase the size of an audio amp's cooling fins as a function of power rating. In the same way, the Earth's thermal radiation capacity is limited by the size of the Earth and any and all properties that affect its total emissivity. e #337 What I explain above applies in the same way to what you bring up here. You seem to have ignored the words "in a way that exactly compensated...", which implies a difference that accounts for energy that is "temporarily" being stored. And "temporary" really means "permanant" as long as the additional flux is present.
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  43. RSVP, ok I'll play... now its a dam. So in the scenario you posit with the "narrow slot" the outflow of water is constrained... the inflow can increase without the outflow increasing in turn (until the water level rises so high that it overtops the dam). Please explain what mechanism you think exists which similarly constrains the outflow of energy from the Earth to a fixed amount. Also, decreasing the outflow by 100x is still going to cause the temperature to rise one hundred times faster than increasing the inflow by 1x. So we're still looking at AWH warming being an insignificant factor unless your unexplained mechanism for constraining radiation outflow is itself somehow immune from being blocked by greenhouse gases. So there you go. Your analogy can work. You just have to explain two little things which violate the laws of physics as we know them.
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  44. #336: "that energy being injected into the environment is having no impact, (instead of warming things, it hightails for the stars)" All energy injected into the environment does not hightail for the stars ... some of it is trapped (or at least stored temporarily) here in an atmosphere increasingly rich in GHGs. Of course, those same GHGs also trap some of the far larger supply of energy from the sun. But bottom line, RSVP is a warmist!
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  45. Analogies and their issues; Analogies are fine when used to explain aspects of a complex system. They fail when you try to use them to disprove that complex system, because the analogy is not a 1-1 mapping. See a much more detailed posting here, motivated by similar logical issues earlier in this topic thread. I wouldn't bother to play the analogy game, CBD - that leads straight to this Bad Analogy error. If you want to disprove a theory or system, you have to do the work there, not in a made-up world whose parameters change with every reply.
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  46. CBDunkerson #342 "Please explain what mechanism you think exists which similarly constrains the outflow of energy from the Earth to a fixed amount." In the third paragraph of #341 I already say that outflow does not only depend on temperature, but also the size of the Earth or more precisely its surface area (which is actually finite believe it or not), plus not everything has the same emissivity, especially the different gases we are breathing all day. It would be interesting to know if you think waste heat could ever cause global warming if CO2 concentration were at its pre Industrial Revolution level. In other words, if there was no anthropogenic CO2 accumulated. Try to imagine that man was still somehow dumping the same 0.474 x 10E21 J of waste heat into the environment each year without the CO2. (Say all nuclear or something.) As calculated above, this is enough energy to raise the temperature of the atmosphere 0.1 degrees in one year (assuming no losses). However, it is fair to assume that some of this energy would immediately begin to thermally radiate and be lost forever, such that after one year the atmosphere's temperature only gets raised 0.01 degrees, or 0.001 degrees. At this point in the discussion it doesnt seem like the number matters, since from what I can tell no one has admitted that this energy could possibly accumulate. You have to remember there is no waste heat night. It never stops, and has generally been on the increase. (see graph at the top of this page) http://en.wikipedia.org/wiki/World_energy_resources_and_consumption
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  47. KR #344 I agree analogies are not one to one.
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  48. RSVP, You are wrong. No amount of repitition of your misconceptions will make them correct. Please read what has already been posted here again, because you have provided nothing new.
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  49. RSVP #345: First, nothing in your reply explains why the radiation outflow from the Earth would have a fixed limit... without such an explanation your analogy has no relation to reality. If your reference to the surface area of the Earth being finite was meant to be such... I'm hard pressed to believe even you can take that argument seriously. The more energy coming into a system, regardless of its size, the more energy must go out. Otherwise we've got energy magically ceasing to exist. "It would be interesting to know if you think waste heat could ever cause global warming if CO2 concentration were at its pre Industrial Revolution level." Can't have been too interesting... given that I already answered that question earlier in this thread. "At this point in the discussion it doesnt seem like the number matters, since from what I can tell no one has admitted that this energy could possibly accumulate." Correct, waste heat cannot possibly accumulate in the climate system. Again, barring some explanation for why an increase in energy input would NOT result in a corresponding increase in energy output (the 'narrow slot' in your dam analogy) it is impossible for any such input to 'accumulate over time'. The current waste heat level causes a temperature increase, which causes greater radiation outflow, which prevents any further temperature increase.
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  50. #348 CBDunkerson The follow, http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law ...starts saying... "The Stefan–Boltzmann law, also known as Stefan's law, states that the total energy radiated per unit surface area of a black body per unit time" note the words, "per unit", "per time" You are right in saying thinking alone the lines "what goes up, must come down", but for some reason you are ignoring the idea that time it takes to "go up, and down" could vary. As I was saying about the heat sink on the back of an audio amp. They dont make them bigger for nothing. The more area, the faster the heat can radiate, so as to not allow the amp to overheat (for instance). Likewise to our earlier analogy, the viscosity of water is a real force that impedes flow. So in the same way they have to actually spend more money for larger pipes to get large amount of water to where it needs to go in a timely manner. http://en.wikipedia.org/wiki/Viscosity And more to the point, if the heat flow outward is being restricted by GHGs (and that is a big IF), it could only be helping the accumuation of waste heat.
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