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Climate Hustle

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 351 to 356 out of 356:

  1. #348 CBDunkerson (resending after cleaning up, and adding just a little more)

    The follow,
    http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law
    ...starts by 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 surface area", and "per time"

    You are right in thinking along the lines "what goes up, must come down", but for some reason you are ignoring the idea that the time it takes to "go up, and down" could vary (depending on conditions).

    As I was saying about the heat sink on the back of an audio amp. They dont make them bigger for nothing. The more surface 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. AND as the surface area of the Earth is finite, this will limit the amount of energy released per unit time. If you wait long enough. If there was a break in waste heat emmision, the Earth would have a chance to get rid of it, but we never stop emitting this heat.
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  2. Yes, RSVP, GHGs of course do slow the escape of waste heat. But GHGs do that equally as they slow the escape of heat from all other sources, including the Earth's heat resulting from incoming solar radiation. That's why the orders of magnitude lower quantities of waste heat make it inconsequential to worry about. That's also why GHG increase is consequential to worry about: GHGs slow the escape of heat from all sources.
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  3. RSVP #350: "And more to the point, if the heat flow outward is being restricted by GHGs (and that is a big IF)"

    No, that is an observed fact which even most 'skeptics' no longer challenge. Indeed, the latest fad seems to be claiming that this is a strawman invented by warmists because no one would ever actually question something so obvious.

    "The follow,
    http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law
    ...starts by 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"

    ...and continues, "...is directly proportional to the fourth power of the black body's thermodynamic temperature T:"

    The amount of energy radiated is directly proportional to the temperature. Ergo, if the temperature goes up the energy radiated goes up. Precisely what I've been saying. No 'fixed limit'.

    And with that stunning example of deliberate misrepresentation on your part, I'm done here.
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  4. CBDunkerson #352

    "No, that is an observed fact which even most 'skeptics' no longer challenge."

    My post #317 was a very crude estimate of how much energy it takes to heat a mass of air comparable to a good part of the troposphere. As I said earlier, the calculation is not precise (nor has to be for what we are discussing) given that density varies with altitude, etc., It can be said that it approximate, and moreover, if making the same assumption about constant density, it can allow us in the same to compare and examine how GHG could possibly be raising the temperature of the atmosphere 30 degrees. That is, when you use the same value 5E21 J/C (which is the energy required to raise that 5E18 kg mass of air 1 degree centigrade), it would then require 150E21 (or 1.5E23) Joules to do so for 30 degrees (which is supposedly where GHGs have left things).

    According to http://en.wikipedia.org/wiki/ Earth, the surface area of the Earth is 5.1E8 km2 or 5.1E14 m2. But only half of that is receiving sunshine at anyone time, which requires us to consider only 2.55E14m2.

    Likewise, according to http://en.wikipedia.org/wiki/Insolation, the average amount of energy received on the Earth's surface is around 1000 W/m2, multiplying by the surface gives us 2.55E17W. Assuming 12 hours of sunshine (43200 sec), we get 1.1E22 Joules from the Sun.

    This is interesting, because it takes 1.5E23 Joules to raise the air temperature 30 degrees, which is ten times the amount of energy actually coming from the Sun. Supposedly, the GHG effect represents only a fraction of a quantity of energy that is deficient in its totality to produce the said result.

    Furthermore, air temperature fluctuations (manifested as what we call "weather") change on a daily and hourly basis with excursions that fully "outwit" the theory.

    What does this all mean? For one thing, energy is being stored whether you like it or not, and it is being liberated from all whereabouts and materials, primarily the oceans. Second, in my calculations, I must be considering too much air (the problem at hand must be limited to a lower altitude). This makes sense, because we know that its much colder at 27,000 feet than "near the ground". But remember that the both calculations used the same mass of air, and you have been using a comparison of energy numbers to claim that GHGs dwarfs waste heat, aside from other claims about energy not accumulating.

    One more thing, and if you decide to reply, please dont pick what you may consider the easiest issue to contest. I was thinking maybe there is confusion about hot air and heat. There is a difference. Air may cool, but that doesnt mean the heat is lost, this having to do with idea that hot air disperses. By this I mean that if a huge warm mass of air spreads out, that heat may raise the temperature of air somewhere else very little. And as you say, since radiation radiates as the temperature to the fourth power, heat will be lost much slower for lower temperatures.
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  5. @RSVP: "This is interesting, because it takes 1.5E23 Joules to raise the air temperature 30 degrees, which is ten times the amount of energy actually coming from the Sun."

    Good thing the sun is emitting this energy constantly, huh?

    It's not clear what you're trying to do, here, RSVP, but if you're trying to disprove the Greenhouse effect you're wasting your time.

    The fact is you haven't demonstrated that waste heat is anything more than about 1% of GHG forcings. You lost that debate. Time to move on.
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  6. RSVP #353
    "...I must be considering too much air (the problem at hand must be limited to a lower altitude). This makes sense, because we know that its much colder at 27,000 feet than "near the ground". "

    so continuing... with this idea...

    you can assume less air, and make the comparison for 2700 feet, one tenth of the height, so as to equal the amount of energy to raise the temperature of air 30 degrees, to that which is received in a twelve hour period.

    The question arises, as this is just the amount of energy to warm this amount of air 30 degrees, what is left to warm the surface as well? A surface that is contantly radiating during the full 24 hours. The altitude to consider must be lower then. So, lets take it down to 1000 feet for the comparison. Now there is energy for warming that amount of air 30 degrees, and double for the surface which is radiating constantly. The 30 degrees may as well be due to convection for all we need to care. Its doesnt really matter, since the object here is to figure out how much air to consider for a comparison of solar to the effects of waste heat.

    If you now only consider the mass of air associated with 1000 feet around the entire globe (instead of 27000 feet), the effects of waste heat as calculated earlier goes up 27 times. Crossing you fingers doesnt make this energy dissapear, yet it is always considered insignificant to what can be imagined as a greenhouse effect.

    I have lost the debate here not for what I have said, as the numbers speak for themselves, but for commitment to an entrenched theory.

    Whether the GHG is real or not shouldnt really matter to anyone that is truely concerned with global warming, since fossil fuels are running out anyway. Waste heat on the other hand will always be an inconvenient truth, whether it comes from nuclear, or changes in albedo due to urbanization, solar panels, highways, etc. For this reason, I understand how it is not an attractive topic, especially for those with optimism about the alternative energy sources.
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  7. RSVP - You should be intimately familiar with this thread, as you account for a fair number of the >350 posts on it. Industrial heat accounts for ~1% that of the greenhouse effect, and hence is just about irrelevant.

    Which you should really know by now. I cannot understand why you are still going on about this disproven argument.
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  8. KR
    I hope you are not confusing the term "waste heat" with that portion of the energy liberated by fossil fuels and nuclear energy sources that is not serving some "human purpose". The term waste may be misleading in this sense. It should be understood as all energy delivered by all fossil fuels and nuclear reactors since the start of the industrial revolution. And if you wish, you might also add the burning of trees for steam engines as this perhaps marked the beginning of an inbalance etc.

    What you dont seem to want to admit is that this energy is in backlog of whatever is considered equilibrium and therefore constitutes an excess which can only have been accumulating. Before considering any GHG effects, you must consider this energy from a cumulative standpoint. Any heating above this perhaps is due to your sold called GHG effect.
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  9. Another way to look a this problem. Picture yourself in a satellite orbiting the Earth. Its ability to cool will depend on an initial design. If on this satellite you have some interal heat sources that are not regulated by any "thermostats", after a while you will be calling Houston.
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  10. RSVP - Gah, you are still holding to this argument. I'm saddened.

    By "Industrial heat" I mean (as does the post that this thread is based upon) all energy usage, as it goes it's inevitable way towards entropy and heat.

    That 1% extra energy has been added to the climate, and leaving, as long as we've been pumping out greenhouse gases. Heat generated at ground level; much like sunlight warming the ground level. Both are components in the energy budget, both are eventually radiated out to space.

    Readers (other than RSVP) - the argument(s) presented through this thread by RSVP are that there are somehow differences between heat from our energy use and heat from sunlight, with the former in some fashion immune (in some undefined fashion) to radiating to space. What that difference is has never been explained to anyone's satisfaction, and there have been zero references presented to support that odd contention.

    It's a forcing, RSVP, like any other forcing, and it's tiny by comparison to the ones we're actually worried about. Energy raises temperature, raised temperature radiates more to space, things head back to equilibrium. There is no plausible mechanism for industrial energy to "accumulate". I suggest you re-read the thread.

    Heat from our energy expenditures is part of the energy budget - at 1% that of greenhouse gas forcing, accounting for rather under 0.01C total of warming. It is, hence, rather irrelevant to current warming concerns.
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  11. RSVP#358: " all energy delivered by all fossil fuels and nuclear reactors ... this energy is in backlog of whatever is considered equilibrium and therefore constitutes an excess which can only have been accumulating."

    Suppose for a moment that this is correct. We should expect to see 'hot spots' near places that deliver this energy. Indeed we do, when the fires are burning or the discharged coolant (water) is still hot -- I posted a false color IR of an Illinois power plant some time ago, on either this or the prior waste heat thread.

    But if this heat 'accumulates,' it must show up elsewhere in the environment. If RSVP is correct, it should eclipse other forcings. Luckily, we can test this idea: Belgium has an interesting website with thermal IR of a good chunk of the Antwerp area. Unfortunately its lacking in geographic references (and I don't read Belgian), but with Google Earth, you can find yourself.

    On the IR, just off the A12 highway in Stabroek, there is a peculiar rectangle of dark red (hot). Locating this point on GE, it is an old fort surrounded by a shallow water-filled ditch. There are several of these forts plainly visible in IR; Fort Merksem near the port of Antwerp is a beauty. They all have the same sort of shallow water-filled ditch (moat?).

    These are not industrial heat sources. They show up on the IR as hot because the water's low albedo absorbs solar energy. Conclusion: No evidence of accumulated industrial heat. Lots of evidence of solar-heated water.

    Now we must ask: Why doesn't the water cool off?
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  12. KR 360
    If my "thesis" were false, there would be no such thing as social security... the idea that if you tuck away a small amount over time, after many years there will be a significant pile left over.

    Another simple analogy is electronic circuit drift. In this circuit, "ground" is floating, and slowly rising. Unless for some natural causes the overall backdrop average temperatures were decreasing, there is absolutely no reason for this energy not to accumulate, whereas you say "there is no plausable mechanism". It is my understanding that AGW assumes "all things being equal" in terms of the natural average trend, so if all things are equal, the added heat can only be accumulating. I am sure you would feel cheated if the gov. told you they spent your social security pension, and you might want to remark on this if you care to reply.
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  13. muoncounter 361
    One could ask a similar questions about AGW. A so called GHG "fingerprint" would show up as higher high temperatures in arid sunny climates. I dont know if this has been observed, but I have not seen anything mentioned on this. On the other hand, a waste heat "fingerprint" would be all temperatures everywhere generally going up as this heat slowly gets spread around, which is what I do think is happening.

    This is space ship Earth, not unlike the satellite I described in 359. We are taking everything with us. We are liberating stored energy that has been trapped for millions of years and dont even realize why it getting warmer. Eventually something will click. Perhaps when fussion makes this more obvious.
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  14. RSVP@363 So can you explain why the Arctic is warming faster than the industrialised regions that are actually producing the waste heat?
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  15. RSVP,

    We've been round & round on this back in October and before.

    You admitted that anthropogenic heat flux radiates just like solar heat flux does, but still insisted that anthropogenic heat accumulates. Trains and oranges and lakes, oh my!

    You are still wrong and no amount of repetition of your misconceptions will make them correct. Increasing the input will only cause a level increase if the output is restricted.
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  16. DM 364
    You might want to browse here:
    http://www.epa.gov/heatisld/

    ...where it says, "In the evening, the difference can be as high as 22°F (12°C)."

    Are you telling me that temperatures are over 12°C in the Artic? I doubt it.

    Heat can only transfer from something warmer to something cooler, and will always tend to spread as well. So while you may have a local change, the net energy flow will always be towards the Artic, not from the Artic (assuming the Artic is an overall cooler place).

    On the otherhand, I will not deny an acute non linearity affecting temperature in polar region's if there is now water where before there was ice. This situation however is just a bump in the road as we are talking about "global" warming.
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  17. Bibliovermis 365
    "You are still wrong and no amount of repetition of your misconceptions will make them correct"

    It doesnt matter if I am wrong, in the sense that the waste heat that is accumulating doesnt care if you are right or I am wrong. No amount of beautiful theories about GHG is going to stop it. Anyone really paying attention will start looking for a good place to live. In the end, (as as always) its going to be every man for himself.
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  18. RSVP@366 Sorry RSVP, you can't ignore observations that refute your theory by saying there are "just a bump in the road". If the warming is due to waste heat, the warming would be highest were it is generated and would be less the further away from where it is generated as the heat diffuses out. The faster rate of warming in the Arctic than elsewhere directly refutes that theory.

    [incorrect P.S. snipped]
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  19. I'm puzzled, RSVP.

    What mechanism do you propose that:

    a) captures waste heat from human activities, allowing it to accumulate over centuries, while allowing 'waste heat' from solar heating (which is about 10,000 times greater) to escape to space; and

    b) prevents the warmed air in that bottom 1000 feet of atmosphere from rising & mixing with the colder air above, as hot air tends to do? (ever see a thunderstorm?)

    Here's an important question for you.

    If there is some mechanism that traps waste heat over long periods of time, and it only takes 10 days' worth of solar input to provide enough heat to raise air temperatures by 30ºC - why is the bottom 1000 feet of the Earth's atmosphere not a plasma at millions of degrees?

    After all, the sun has been pumping that heat into the atmosphere for literally hundreds of billions of days.

    Unless the waste heat from human activity is some new kind of heat that behaves in a completely different fashion from the heat resulting from solar input, then you have to contend with that four orders of magnitude difference thing.
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  20. RSVP#363: "A so called GHG "fingerprint" would show up as higher high temperatures in arid sunny climates."

    Nonsense. Greenhouse gases mix in the atmosphere. The warming is not localized. Face the music and provide some evidence that supports your waste heat notion. There is plenty that contradicts it.

    #367: "It doesnt matter if I am wrong, in the sense that the waste heat that is accumulating doesnt care if you are right or I am wrong."

    One could conclude that if you are wrong, waste heat is not accumulating. But if that's your take, then never mind.
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  21. Bern 369
    To answer the plasma question. There is no mechanism for trapping waste heat per se, and there is no distinction to be made between waste heat and heat coming from the Sun.

    If the quantity of heat that the Earth is able to eliminate in the course of one year is assumed to be constant, any additional energy liberated by fossil fuels or nuclear reactors is going to be with us in the form of melted glaciers, polar caps and higher ocean temperatures.

    Ironically, AGW has been saying two things. 1) that warming is due to humans, and 2) the ability of Earth to eliminate heat through the atmosphere is actually slower now due to anthropogenic CO2. Based on this premise, the ability of the Earth to eliminate heat has not remained constant, but has lost its efficiency to do so. So even if you dont believe waste heat is significant, you have no basis for denying that this "small" amount of energy is not accumulating, as it is in surplus to what has been reaching us from the sun over the eons. And with this, I am not endorsing AGW. I am only quoting it to say that if you believe it, you should expect heat to be accumulating whether you think its a significant amount or not. The fallacy with the qualatitive argument about waste heat being so little is that the comparison is always being made in terms of Watts per square meter, when the comparison should be for Watt-centuries etc.
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  22. muoncounter 370
    It's not music we have to face, but waste heat.
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  23. RSVP@372 Responding in that way to a challenge to provide some verifiable evidence to support your hypothesis is a tacit admission that you know your position has no evidential foundation.
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  24. RSVP #362: You have some bizarre ideas.
    "the idea that if you tuck away a small amount over time, after many years there will be a significant pile left over."
    "It is my understanding that AGW assumes "all things being equal" in terms of the natural average trend, so if all things are equal, the added heat can only be accumulating."

    Wrong.
    The added heat is a forcing (and a trivially small one at that), and the energy will only accumulate so long as the energy lost from Earth is less than the energy coming into the system. A forcing that introduces a warming does not lead to an endless runaway heating, thank goodness(!!!), but to a slight warming that soon results in the warmer Earth radiating away slightly more energy to balance the heat entering the system. The larger the forcing, the longer Earth takes to come to equilibrium, at which point heat no longer accumulates in the system.

    The GHG forcing is much larger, resulting in a longer time for Earth to come to equilibrium, and a much greater knock-on effect in the form of feedbacks which exaggerate the warming. Eventually, Earth will come to equilibrium, with excess heat being radiated away balancing higher temperatures, a new lower albedo, and higher GHG concentration. Where that equilibrium is, and the size of the changes that it has effected on the Earth's surface, are non-trivial questions for humanity.

    The waste heat forcing is tiny, and so the Earth system can relatively easily reach equilibrium with this small extra forcing, which results in a total warming that is virtually undetectable in temperature records.

    #366 - your comment makes little sense, but I'd be interested to know where you think the greatest temperature difference should be, at the source of waste heat, or in the Arctic, far from the sources, given that as you say, the heat spreads out through diffusion?
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  25. This is deja vu all over again...

    As DM@737 points out, until RSVP provides some evidence (the kind with measurements and numbers and math)there is nothing here but supposition.
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  26. skywatcher 374
    "You have some bizarre ideas"

    Not sure if you believe that that energy accumulates for a given location as it moves from sunrise to noon, yet I do think this happens. I also consider this diurnal radiant forcing as a pulse with a a duty cycle that goes from nil to 100% depending on the latitude and season etc. Similarly, you have a longer energy pulse superimposing this one with a 50% duty cycle spanning six months for each hemisphere. Superposition would therefore result in an overall accumuation which would basically explain how termperatures generally peak somewhere past noon and in summer months. Energy that carries over through the mins is therefore accumulating.

    In the same way, with waste heat we have a relatively low level but very long energy pulse that started with the Industrial Revolution, wherein the peak has not yet been reached. Remember that on the average this energy is being liberated day and night all over the planet non stop...no breaks, no nights no winters. Given that this pulse has been on the increase for around 200 years, it should take that long just to discharge this same energy.

    If as you say, waste heat is just another forcing, the same rules should apply to it for the way heat accumulates in the upswing phases of diurnal and annual solar cycles. But if you find this bizzare, please let me know in what way. Thanks.
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  27. RSVP@376
    "Remember that on the average this energy is being liberated day and night all over the planet non stop...no breaks, no nights no winters."

    How much energy are we talking about here?
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  28. RSVP#376: "an overall accumuation which would basically explain how termperatures generally peak somewhere past noon and in summer months."

    Can't argue with you there. Summers are hotter than winters; late-afternoon is the hottest part of the day. Is this news? Was this in need of an explanation?

    "with waste heat we have a relatively low level but very long energy pulse "

    Do you have any empirical evidence for the accumulation of waste heat? Do you have any response to the evidence which shows that waste heat accumulation is invisible on IR, despite the fact that solar heat accumulation is quite visible?
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  29. This is amusing, in a rather painful fashion.

    RSVP - Does your "accumulation" not warm the Earth? Does that temperature rise not radiate more IR, acting as a limiting feedback?

    If the climate response takes (for the sake of argument) about 40 years to fully respond to a forcing, you're only looking at the unrealized warming of the last 40 years, perhaps half the energy output of the last 150 years.

    That means that half of the warming (0.005C) has been realized, and that half (0.005C) is yet to be realized. And when it is, well, the Earth will radiate a teeny bit more IR.

    You're still claiming that energy use is somehow qualitatively different from greenhouse gas entrapment, that the heat from energy use doesn't radiate IR like the heat from the sun and take part in the Stefan-Boltzmann negative feedback and boundary conditions. That, to put it mildly, is ridiculous!
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  30. muoncounter 378
    "Can't argue with you there. Summers are hotter than winters; late-afternoon is the hottest part of the day. Is this news? Was this in need of an explanation?"

    Depends. Someone might want to believe that a day temperature high was higher (in late Spring for instance) due solely to the extra minutes that the Sun had radiated that day, when in fact it is in the main due to heat that was progressively accumulating throughout the season.

    As long as the pulse is ON, the energy is building, and idea that is perfectly consistent with the 1st Law of Thermodynamics.
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  31. pbjamm 377
    "How much energy are we talking about here? "

    If the value 0.028 W/m2 is correct, simply multiply this by the surface area of the Earth and then multiply by the years for which this value is the case. The total time is around 200 years, while the value 0.028 generally approaches zero as you go backwards.
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  32. RSVP 381

    Why do you stop at 200 years? Prior to that the energy released must have been smaller but had been accumulating for 1000's of years surely?

    Why is visible light not accumulating also?
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  33. KR 379
    "You're still claiming that energy use is somehow qualitatively different from greenhouse gas entrapment, that the heat from energy use doesn't radiate IR like the heat from the sun "

    Remember the form of the Stephan Boltzmann's Law that relates to what you are talking about contains the letter A. A is for area. What is the surface area when you are talking about energy delivered in a reciprocating internal combustion engine, or ocean water cooling a nuclear power plant?
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  34. MichaelM 382
    "Why do you stop at 200 years? "
    I said "generally approaches zero" just for the reason, otherwise I would have said "reaches" zero. As long as it has been growing, you are right. And the issue (I believe) is not overall climate change, but that part which is due to humans.
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  35. RSVP - "Stephan Boltzmann's Law ... contains the letter A. A is for area. What is the surface area when you are talking about energy delivered in a reciprocating internal combustion engine, or ocean water cooling a nuclear power plant? " (emphasis added)

    Are you arguing, then, that our energy use fails to radiate because it's more concentrated? Well, at least that's a fairly new one...

    But that's a complete 'fail' as an argument - Trenberth pointed out that his initial energy budget underestimated surface radiation (390 W/m^2 vs 396 W/m^2 in the 2009 update), due to the T^4 relationship and temperature variances. Variances from an even temperature increase outgoing IR (cooling the planet more) because an upwards variance puts out much more energy than a downward variance inhibits.

    So to the extent that our energy use is concentrated it's warming effects will be minimized - you argue against yourself.

    Secondly, you've argued that waste heat is causing the warming we attribute to GHG's - but warming increases radiation to space, so again there's no "accumulation". In fact, if waste heat was the cause of warming, we would see an increase in outward IR due to the planet being over equilibrium temperature, rather than the observed decrease as the climate catches up to the GHG forcing.

    -----



    New readers: All of this is covered in the previous months of discussion on this thread. "Waste heat" as a cause of global warming is two orders of magnitude too small to be the issue despite RSVP's fixation on it, and I would encourage anyone interested in the issue to just read the post at the top and follow the thread if you have more questions. DNFTT.
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  36. KR 385
    Going here...
    http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law

    it happens to say...
    "To find the total absolute power of energy radiated for an object we have to take into account the surface area, A(in m2)"

    In the case of heat convecting directly into fluids such as air and water, A (the area) equals zero since there are no solid objects radiating anything. We are talking about air and water. The SB law refers to solid black and grey bodies. Conclusion. If A is zero, J is zero, which means energy radiated is zero.
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  37. RSVP - "In the case of heat convecting directly into fluids such as air and water, A (the area) equals zero since there are no solid objects radiating anything. ... If A is zero, J is zero, which means energy radiated is zero."

    Horribly, horribly wrong, RSVP. Water radiates from its surface, gases radiate as well, with the W/m^2 being the flux that gas will radiate through a 1 m^2 area - scaled from your detector aperture. Solid, liquid, gas, plasma - all matter above absolute zero radiates some thermal energy.

    Here's a hint - a non-zero emissivity means thermal radiation. Water, for example, has an IR emissivity of 0.98, almost black body levels. Your post is complete nonsense.

    You've been a participant here for quite some time, RSVP - why are you grasping at what aren't even straws in this case? You should know better by now!
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  38. Following RSVP, the sun doesn't shine. Don't believe your lying eyes!
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  39. Riccardo - So true, so true; in RSVP's universe that hot ball of gas doesn't emit thermal radiation...

    Reductio ad truly absurdum - (Latin: "reduction to the absurd")
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  40. KR 387
    "Water radiates from its surface"

    And what percentage of the ocean's mass does the surface comprise? Similarly, 98% or so of the atmosphere is NOT water vapor, or CO2. So I will grant you my post was wrong for not considering this minutia, (i.e AWG's cornerstone).

    And far as Riccardo (and you) confusing nuclear physics with classic heat transfer theory, I would ask who exactly is grasping at straws now? I dont think that helped Riccardo as nuclear physics is just a little off topic, however if you think we are talking about the same thing please expand. By the way, as it turns out emissivity drops off rather quickly for the temperatures you are referring to.
    ( -Snip- )
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    Moderator Response: [DB] Pointless and inflammatory sentence fragment snipped.
  41. 390 RSVP "not considering this minutia,"

    I think you may be getting that the wrong way round... as did a number of folk on the 2nd Law post.

    Basic thermodynamics, statistical mechanics and e-m theory work irrespective of the Minutiæ of the system under consideration. Anything, in which ever phase - gas, liquid, solid, plasma, Bose–Einstein condensate - will have an affective area, temperature, radiative spectrum etc. Things like surface area may not be exactly what one 'sees' - radiation may or may not be able to escape from within the body of the object, changing, for example, the affective surface area. But it matters not the the physics.

    Some of these abstractions of physics can be hard for folks to grasp but I would strongly advise people to tread carefully in such areas - for no other reason than to avoid another 1000+ post thread squabbling over pure confusion about physics!
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  42. RSVP#390: "not considering this minutia,"

    If by minutiae, you mean evidence. Your statement:

    ... fluids such as air and water, A (the area) equals zero ... Conclusion: If A is zero, J is zero, which means energy radiated is zero ...

    clearly says fluids don't radiate energy. You've been shown evidence (more of that minutiae) here and here that your 'conclusion' is utterly wrong.

    Your continued persistence in accepting this only makes your entire argument less credible than ever.
    0 0
  43. and what import does the radiation between molecules have if all they do is exchange energy between themselves? Here we have 100% cancellation of anything remotely resembling a cooling mechanism, as the only thing that matters is the net vector from the surface skyward.
    0 0
  44. Not sure if anyone has used this analogy yet. Global warming as obesity. When a person is overweight, there are usually many causes, but they all reduce to the net ratio of calorie intake over calories burned greater than unity. And while this idea is fairly simple, it's not always clear why doing all the right things doesnt result in a desired weight loss. For one thing, there are time delays associated with metabolic processes that introduce lag. Things take time. In the same way, to say that radiative heat will simply increase to offset the effects of waste heat is not recognizing inherent lag. You cant just fixate on the SB formula and think it is going to solve all your problems.

    Picture a nuclear power plant next to a river. If I were to accept the arguments being proposed here against waste heat, I would have to believe that as soon as the water comes out of the plant it will cooled to the same temperature above the plant. Everyone knows this is not the case. So I would ask how far downstream must one go for the heat to magically disappear, making me "horribly, horribly" wrong?
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  45. For the most sea worthy ships, waves may wash on deck. No problem; when built properly, there are amply ways for the water to return to the sea. For this reason, the ship does not sink. Put a small hole in the hull however, and if there is no bailing, eventually the proud vessel will find its davy jones.

    Our spaceship Earth is no different. All surfaces that pick up heat from the Sun act conversely to radiate the same. While a slight change in CO2 may be changing the atmospheric temperature profile, the net entropy remains unchanged. And while energy cannot be destroyed, the same cannot be said for our lovely Planet.
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  46. RSVP - Re: my rhetorical question about cherry-picking from the middle of publications: "For the same reason you didnt answer the question about the social security analogy?"

    I didn't answer your social security analogy because it's a horrible analogy, one that doesn't map to the climate system.

    Sunlight puts energy into the climate, adding to the surface air temperature (SAT) and ocean heat content (OHC), which then radiate increased IR to space. Waste heat also does the same, but at a level only 1% that of sunlight. It's not measurable as a climate effect until it shows up in the OHC and SAT, at which point the same temperature^4 radiation feedback applies to both.

    You're still treating waste heat as a separate pool of energy that somehow doesn't affect surface radiation (which it could only do if it didn't affect surface temperatures!), which is quite an unjustified and unphysical position to hold.
    0 0
  47. KR 396
    "which it (waste heat) could only do if it didn't affect surface temperatures"

    Surface temperature is only skin deep. If thermal radiation was the only heat transfer mechanism, you would be absolutely correct. Conduction however leads to heat storage within solids. The warmer a thing gets, the deeper the heat penetrates, and therefore, the longer it takes to come back to the surface. There are similar considerations for fluids, especially as affects thermal water pollution. Your model completely ignores these realities.

    On the otherhand, you are correct to the extent that waste heat might increase surface radiation, this would help in subtracting from the overall "accumulated" energy. And referring to the analogy, perhaps that would be the effects of inflation on your pension.
    0 0
  48. RSVP - If your energy was buried, as you hypothesize, it won't affect the climate until it surfaces. If it surfaces, it warms the climate, and as climate temperature is subject to the same mechanisms (thermal IR, convection, evaporation) as sunlight inputs.

    Hence - no go, RSVP. Even if waste heat was somehow buried (and you have provided no references, citations, or other evidence thereof, so it's firmly at the "what if" level), there's no effect on climate until it surfaces, at which point it's part of the process, subject to the same energy equilibrium with sunlight. Which is 2 orders of magnitude larger.

    Your attempts to rescue a dead skeptic argument are impressive in their energy, but there's really no resuscitation possible here.
    0 0
  49. KR #398
    "there's no effect on climate until it ("buried energy") surfaces"

    I can only assume you deny the effects of convective heat transfer because your models do not include them. Likewise, if you deny the existence of heat conduction in materials, in preference to science fiction, I suppose we are speaking in different languages.
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  50. KR 398
    "Which is 2 orders of magnitude larger. "

    Interesting to know if you theoretically allow any amount of waste heat to cause a global warming effect.

    From what you have repeated many times, as the amount of waste heat energy dumped into the environment increases, temperature goes up, and all this just makes for more outward radiation, and therefore there is no concern for global warming on the account of waste heat. On the otherhand, in post 398 (and possibly other places), the "two order of magnitude" energy difference does seems to matter.

    Is it possible to mend this contradiction?
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