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What is Global Warming and the Greenhouse Effect?

Posted on 30 June 2010 by Kevin Judd

Guest post by Kevin Judd

Climate scientists are telling us that gases like carbon dioxide are causing global warming. Carbon dioxide is produced when petrol is burned in your car engine, or when coal and gas are burned at power-stations to make electricity. Carbon dioxide causes global warming because it contributes to the so-called greenhouse effect. So what is this greenhouse effect?

Winter is a good opportunity to observe the greenhouse effect in action. It should be obvious that sunlight heats the earth: it gets hotter when the sun shines, and colder at night when it doesn't. On clear dry nights it can get very cold indeed, but if the sky is cloudy, or overcast, then it doesn't get so cold. This happens because clouds trap heat. The more clouds there are, the warmer it stays overnight.

So how does this heat trapping work? And how does carbon dioxide come into play?

You know that radio stations have different frequencies. When you tune your radio to your favourite station, you are telling your radio receiver to block all radio-frequencies except those that the station uses. These frequencies are allowed into the radio's electronics.

Heat, just like radio-waves, has different frequencies, and clouds, just like a radio receiver, block certain frequencies of heat and allow other frequencies through. Without clouds most frequencies of heat escape into space and it gets very cold overnight. When there are clouds, some frequencies of heat are blocked from escaping into space, keeping it warmer.

It turns out that clouds and carbon dioxide trap heat differently, like radios tuned to different frequencies. In fact, carbon dioxide pretty much blocks precisely those frequencies that clouds would allow through. Add to this the fact that unlike clouds, which come and go, carbon dioxide is always there, its warming effect occurs even when the sky is clear and dry. You can probably understand now why climate scientists are so concerned about carbon dioxide. The more carbon dioxide in the atmosphere, the hotter the earth will become.

Of course, this is a simplified explanation of global warming, but the basic story I have just told you is correct. Scientists have known and understood this for over 100 years, and it has been confirmed in laboratory experiments. There is no doubt about the basic science behind global warming.

So does it really matter that driving a car and using electricity adds more carbon dioxide to the atmosphere? In my next segment, I will examine why scientists are convinced that if we are not careful, the earth will warm 2 or more degrees, and I will examine what the consequences of this will be.

The message for today, however, is that anyone who tells you that carbon dioxide does not cause global warming, either does not understand the basic science, or is being deliberately misleading.

NOTE: this post is also being "climatecast" by Kevin Judd on RTR-FM 92.1 around 11.30 AM WAST today. You can listen to a streaming broadcast of RTR-FM online via http://www.rtrfm.com.au/listen.

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Comments 1 to 50 out of 73:

  1. "..The message for today, however, is that anyone who tells you that carbon dioxide does not cause global warming, either does not understand the basic science, or is being deliberately misleading."

    Bias.

    Increase in Carbon dioxide does not assure Global Warming. There are more variables to the equation.

    Article presents a simplistic argument. Nature has more variablity, and more inputs than simply an increase in Carbon Dioxide.
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    Response: Increase in Carbon dioxide does not assure Global Warming. There are more variables to the equation.

    This issue is examined in detail at CO2 is not the only driver of climate.
  2. For more fully fleshed-out versions of what Karl_from_Wylie speaks of when he mentions other variables, natural variability and the like, there are numerous articles here on Skeptical Science providing information on those topics. The View All Arguments is a fun place to start.

    Another terrific resource is a book by historian of science Spencer Weart. His history of this topic The Discovery of Global Warming is freely available for reading online as well as being available in print.
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  3. Well lets see. In terms of energy balance, climate = function(solar, aerosol, albedo, GHG). The complication is indeed feedback. However, if you increase GHG, you need to find a negative feedback that works with increasing GHG to avoid warming. Constraint - this negative feedback has to work in such a way that variations in solar on the earth's surface will also give us the ice ages (or give us an alternative model for ice age cycle). I havent seen anything credible. The much-talked about cloud feedback is response to temperature so if it reduces sensitivity to GHG so much how come it doesnt impede the sensitivity to solar change?
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  4. Karl,

    it's not very useful to tell people through a quick sound byte on the radio that global temperature change is a function of the net radiative forcing. There's nothing wrong with this approach...CO2 is, and will be, the largest forcing agent driving climate change from the pre-industrial/industrial transition era all the way into the foreseeable future. That other things can offset CO2 is important, especially on relatively short timescales, but no other negative forcing is persistent and strong enough to offset our CO2 which will enhance the greenhouse effect on timescales of centuries to millennia. At least not anything within the bounds of physical plausibility.
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  5. Karl_from_Wylie

    Bias.

    Increase in Carbon dioxide does not assure Global Warming. There are more variables to the equation.


    It is noted that you provided not one shred of evidence for your assertion.

    You overlooked this:

    Of course, this is a simplified explanation of global warming, ...


    Which rather demolishes the entire point of your post. Perhaps you should learn to read more carefully.
    Skeptical Science has debunked numerous claims made by a well funded denial industry.

    Smoke, Mirrors & Hot Air: How ExxonMobil Uses Big Tobacco's Tactics to Manufacture Uncertainty on Climate Science

    Koch Industries Secretly Funding the Climate Denial Machine

    Crescendo to Climategate Cacophony Behind the 2006 Wegman Report and Two Decades of Climate Anti-Science - John R. Mashey
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  6. Comparing CO2 to clouds is wrong. Clouds are not a greenhouse gas.
    Water vapour is however, and it is always present.
    Whilst much is made of how high CO2 levels may rise to, there seems to be little mention made of how much the water vapour levels will rise and whether there is an ultimate limit.

    Clouds are also always present providing between 64% and 69% coverage globally.
    Clouds provide an overall nett cooling effect for the planet.
    I believe there is a new paper being prepared for publication in the coming months that examines cosmic rays and cloud formation.
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  7. Whilst much is made of how high CO2 levels may rise to, there seems to be little mention made of how much the water vapour levels will rise and whether there is an ultimate limit.

    Little mention where? Climate scientists have addressed this issue at length, repeatedly. See Water vapor is the most powerful greenhouse gas, just for starters.

    It's one thing to disagree with a specific scientific arguments on water vapor, but to act as though it's being downplayed or ignored is kind of absurd, especially for a longtime commenter on this site. In my experience, there are in fact very few "skeptical" arguments and very few uncertainties of which "little mention" has been made by climate scientists.
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  8. Actually John there is much mentioned of water vapor in anthropogenic climate change research. In short, water vapor is being supplied to the atmosphere in increasing quantities as things warm up and more water vapor makes the problem of warming worse.

    Here are a couple of helpful articles:

    Water vapor and global warming

    Attribution of observed surface humidity changes to human influence

    I believe there is a new paper being prepared for publication in the coming months that examines cosmic rays and cloud formation.

    Indeed, some things never change. Geese migrate, papers on cosmic rays and clouds are prepared for publication.
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  9. #1) Karl_from_Wylie at 14:21 PM on 30 June, 2010

    "Article presents a simplistic argument. Nature has more variablity, and more inputs than simply an increase in Carbon Dioxide."
    **********************************************************************************************
    Karl, I believe this post was intended for the general public and is thus kept somewhat simple on purpose.

    It's not that simplistic, however, when you take note of the fact that you're referring to "Nature". That implies previous events of "Natural Global Warming". However, the focus of this post is about "Man Made Global Warming" in which Carbon Dioxide is the main cause.
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  10. To Kevin Judd
    The style of this writing is very good in that it uses simple and straightforward language, however...

    When seen from above, clouds appear white because they reflect a good part of the visible light spectrum. Clouds appear black underneath, because there is not a lot of visible light emanating from the Earth's surface. If clouds keep heat in as you say, (and I assume you mean locally below the clouds), they must be doing so generally only for IR emanating from the warmed air and surface below the cloud. In addition, they are not absorbing most of this heat but rather reflecting it.

    This is very different from my understanding of the AGW model which focussed on the heat that CO2 itself is absorbs.

    When in fact the word "greenhouse" seems to be more applicable to cloud cover as compared to any "transparent" gas, the analogy of CO2 with clouds seems to break down heartily because of the effects of an abrupt reflective boundary between a cloud and non-clouded air; a boundary that does not exist for CO2.

    Another way to see this would be to assume the Earth were covered completely in clean fog, and ask, would it be cooler or warmer? Or the complement of this question, which would be, "what conditions lead to fog?"
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  11. < Karl, I believe this post was intended for the general public and is thus kept somewhat simple on purpose.>>

    Even the simplest of explanations should be consistent with reality. And I doubt that the "general public" you are referring to come to this site, or even have much interest in global warming theories.
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  12. RSVP, if you're going to quibble with Kevin you'll need to have your facts straight. For starters, you're wrong about how clouds interact with IR. By expressing your confusion as assertions you're spreading your confusion elsewhere. Please don't.
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  13. Carbon dioxide is part of the greenhouse effect, and this does keep the globe warm. Without the greenhouse effect, life would probably not exist.

    does increasing the amount of carbon dioxide enhance the warming effect? The evidence says yes it does, and this is the basis of the Global Warming theory.

    Note: It is not yet (and probably never will be) possible to prove this with absolute statistical certainty, but would you go on 100 plane flights if you only have a 95% chance of surviving each flight?
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  14. Please also remember who we wish to inform and influence. Scientists regularly fail to engage members of the public precisely because they insist on absolute precision, but loose accuracy and effect. This post, for all its generalisations, explains a concept in a way that my mum could understand.

    That is vital
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  15. doug_bostrom, werafa, et all

    "For every action, there is an equal and opposite reaction." That was Newton talking about inelastic collisions between moving bodies. This is accurate, absolute, and true. How does this play out when one mass is that of the Earth, and another, a small rock landing on say a hard cement patio? Does the Earth "react"? Not a whole lot.

    The issue is not whether CO2 aborbs or emits IR. The issue is whether the amount of CO2 is making any measurable difference in climate change. If my assertions sound confusing, it is only because the dynamics are complex. For instance, water vapor is transparent and reflects light depending on temperature and pressure. This means that modeling the effects of just water vapor on its own is complex and non linear.
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  16. RSVP #15, so everything in the article above is true... but you are arguing that the AMOUNT of warming may be negligible.

    Which seems like arguing for the sake of arguing since the article states that this very issue, how much warming is likely to occur, will be covered in a subsequent installment. So leave that aside for when it's actually considered and take this article for what it is... a simple explanation of greenhouse warming which is every bit as "accurate, absolute, and true" as Newton's third law of motion. A point which only need be made because 'skeptics' jump up to object whenever it is... falsely suggesting that there is some doubt on the issue.
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  17. The Science of Global warming---the Greenhouse condition is over 100 years old- and is not 'exotic' but basic science. The science is solid and basic physics.

    The doubt comes from what some believe is the human imprint to warming- which actually has been very strong-

    increased industrialization shows the burning of fossil fuels to have increased CO2 levels to nearly 400ppm.
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  18. I really think that people like John D & RSVP need a sense of perspective. On the one hand you have water vapor, making up 3% of the Earth's atmosphere & accounting for, on average, roughly 65% of the *natural* Greenhouse Effect. Then you have CO2, making up less than 0.03% of the Earth's atmosphere (pre-industrial), yet accounting for almost 20%-on average-of the *natural* Greenhouse Effect. This suggests that, on a parts per million basis, CO2 is about a 20 times more potent greenhouse gas than water vapor. This potency is further amplified by the fact that the resident lifetime of a single CO2 molecule-in the atmosphere-is much, much longer than that of a single molecule of water. Yet we're to believe that artificially ramping up the levels of CO2 in our atmosphere will have only a negligible impact on our climate-in spite of the fact that we've had a greater than 0.6 degree warming in the space of only 60 years-which just happens to coincide with a significant rise in anthropogenic CO2 emissions & a decline in solar activity. Some people appear to believe that we're a bunch of mugs!
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  19. RSVP at 17:17 PM on 30 June, 2010 says:

    "And I doubt that the "general public" you are referring to come to this site, or even have much interest in global warming theories."

    As a member of the general public, I can assure you I come to this site often, refer other members of the general public to this site as a great resource for laypersons to understand scientific concepts, and I appreciate the explanations provided by John Cook, Kevin Judd, Doug Bostrom, and many others.
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  20. What I love is how RSVP can claim that CO2 is too "small" to have an impact on the climate, yet he still holds to the notion that industrial heat-which accounts for less than 0.1% of all the energy this planet receives-is to blame. Talk about holding two contradictory views at the exact same time. A good analogy for CO2 might be a biological toxin like Pertussis or Botulinus. An average human being weighs more than 50kg, yet doses measured in milligrams could prove potentially fatal. There are other toxins which are even more deadly, in smaller doses. Its not the quantity that matters, but the ability to effect the system that matters. CO2, NO2 & CH4 are all *trace* elements, yet they're all exceptionally good at absorbing outgoing IR radiation. This means that you don't need much of them for them to start having a malign impact-just as you don't need much of a compound that blocks neurotransmitter function to kill a person!
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  21. Marcus
    "What I love is how RSVP can claim that CO2 is too "small" to have an impact on the climate, yet he still holds to the notion that industrial heat-which accounts for less than 0.1%..."

    Two things (as the donkey on Shrek said...)

    1) It appears you are directing your comment to readers that you assume agree with you. Are these club members?

    2) Just imagine if CO2 was having zero impact. That then would be saying a lot about how much waste heat is accumulating. Remember integration from college?
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  22. RSVP,
    You seem to be ignoring that water vapor is a feedback, not a forcing, as well as the well known and understood physics of CO2.
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  23. OK RSVP, on point (1)-have a look at the above posts-aside from you & Karl, everything here *does* agree with me-so its a pretty fair assumption. This has nothing to do with belonging to a "club", but everything to do with having more than a basic grasp of scientific concepts.
    (2) if recent warming were the result of accumulating waste heat then (a) there would be some correlation between rising industrialization & rising temperatures (we don't, btw); (b) we'd expect to see the most rapid warming in industrial sites, with non-industrial sites warming less rapidly, if at all (in fact, many wilderness sites-like the Arctic & Antarctic-are warming at a significantly faster rate than urban & industrial sites) & (c) we'd be able to account for every Joule of that energy to *prove* that it was accumulated waste heat. As I've said before, waste heat accounts for as little as 0.01% of all the energy the planet receives (about 13 Terra-watts), as compared to the roughly 180 Peta-watts worth of solar radiation that enters the system from the sun.
    So, on all 3 of these counts, your "it's waste heat" hypothesis falls flat on its face-& no amount of repeating a dud hypothesis will suddenly make it good.
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  24. Oh, & "imagining" CO2 has no impact is very different from it actually *having* no impact. We know-& can directly measure-the impact CO2 has on outgoing long-wave radiation, & even its natural (non-enhanced) effects totally dwarf any known impacts of thermal pollution by several orders of magnitude.
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  25. Marcus
    "your "it's waste heat" hypothesis falls flat on its face-"
    Not so fast...
    One thing you can be sure of is that waste heat is entering the atmosphere. (If this were not true, my car's engine would overheat.) And its not just heating the CO2. Its heating all gasses, even those that do not emit IR so well (as per AGW).

    Similar problems exist for thermal pollution entering our rivers and the ocean.

    After that, this same heat has to go through the CO2 gauntlet upward, which you adamantly profess has made heat escaping more difficult. Just as can happen with commuter traffic, when the throughput increases, you get a traffic jam. This happens even when the same number of lanes are free. Just imagine if a lane gets closed (this would be the CO2 factor). So, it may be a combination of both effects.
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  26. Not to make it 'pick on RSVP' day. But...

    "...any "transparent" gas..."
    "...water vapor is transparent and reflects light depending on temperature and pressure..."

    OK, I might not be getting what you are meaning here, but 'transparent' is a poor term for gasses. Mainly because their transparency is function of the wavelength of the light, not temperature and pressure, btw. Water vapor and CO2 are transparent at some wavelengths and not at others. That's kind of the whole reason why there is a greenhouse effect.

    "...and non linear. "
    Right, we know that; it is a log function. (Unless you are talking about how water vapor condenses and precipitates, but that is the part that isn't clear.)

    "...waste heat is accumulating."
    Hmm, if the absorption and emission of IR (heat), and hence retention, is negligibly affected by an increase in an IR absorbing gas, like H2O and CO2, what keeps the waste heat from radiating off into space? The only thing that would prevent that would be a greenhouse effect stronger than AGW needs, yet you are arguing that there isn't a greenhouse effect strong enough to let AGW happen.
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  27. Marcus
    "This potency is further amplified by the fact that the resident lifetime of a single CO2 molecule-in the atmosphere-is much, much longer than that of a single molecule of water. "

    Two things.

    1) I think it was Shrek, not the donkey. So I will admit making a mistake on that count.

    2) I assume your water molecules get replaced by other water molecules such that the overall amount of water vapor remains relatively constant (on the average). If so, not sure why this matters? Not only that, it just happens to take energy for this to happen, which is a plus for global cooling.
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  28. RSVP - while all sources of heat do feed into the equation, a simple order of magnitude calculation indicates that waste industrial heat accounts for one part in 10,000 of global warming compared to radiative imbalances.

    So yes, industrial heat does add to global heating, but not enough to matter - not even enough to show up over noise/chaotic daily weather/measurement error/phase of the moon (Joking on that last one, joking! Although I believe lunar irradiance does have some effect...).
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  29. Hopscotching comments here.

    Regarding #25, OK, so waste heat has to "...go through the CO2 gauntlet..." the same as the energy from the sun after the earth has, in effect, converted SW to LW. The amount of energy in has to be on long-term balance with energy out; so, how much energy does the earth receive from the sun compared to how much industry puts out? The sun's energy is orders of magnitude larger. Yet, somehow waste heat has a larger impact?
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  30. RSVP,
    I assume your water molecules get replaced by other water molecules such that the overall amount of water vapor remains relatively constant (on the average).

    So water vapor remains relatively constant and global temperature keeps rising? Seems to me you just ruled out water vapor as a cause for GW.
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  31. NickD wrote :


    "As a member of the general public, I can assure you I come to this site often, refer other members of the general public to this site as a great resource for laypersons to understand scientific concepts, and I appreciate the explanations provided by John Cook, Kevin Judd, Doug Bostrom, and many others."


    Hear, hear and seconded.
    I would also like to add mention in the dispatches to Marcus, Ned, David Grocott and ChrisG, who always have detailed and referenced answers to all the strange theories and assertions that some people post on this site, especially recently.
    I admire the forbearance of you all...
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  32. Regarding #27(2),
    When a water molecule evaporates from, say, the ocean, energy is transferred from the ocean to the atmosphere. When the molecule condenses back into rain, and precipitates, energy is transferred back. The net effect is zero. How does this contribute to global cooling? (At what altitude (range) does most precipitation form and is that high enough to significantly affect how readily it is radiated out?)
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  33. < ...

    "...any "transparent" gas..."
    "...and non linear. "
    "...waste heat is accumulating."
    >>
    Addressing your comment...
    The nonlinearity I was talking about has to do with how water vapor "turns opaque" (i.e. reflects white light) on the turn of a dime as per triple state diagram.

    As far as what I was talking about in terms of waste heat...
    I am saying that a thermal radiator such as that of my car's engine heats up air. AGW rests on the assumption that 97% of "air" is transparent to IR. This means that it is just as bad a emitter of IR as absorber. So please explain how this warmed up air is suppose to cool?
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  34. I have a tendency to be exacting; so, I've been mulling over the words I used in #32, and I think they are not quite right. I'd think that would be some energy left behind in the air media, and would begin a journey at the point of condensation. If that condensation occurs at 500 feet, then it probably makes little difference whether it started there or at the surface; if it begins at the top of a thunderhead, say near 40,000 feet, then it probably does.

    Regardless, the amount of water vapor in the air, over the ocean, is largely dependent on temperature (and altitude). The overall effect of clouds, considering high and low altitude, day and night, is still in contention, but water vapor is always a GHG. So, I wouldn't look to a cooling effect of clouds, which require water vapor to form, as a cooling effect greater than the warming effect of CO2 and water vapor combined.
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  35. Karl_from_Wylie wrote:

    =========================================
    "..The message for today, however, is that anyone who tells you that carbon dioxide does not cause global warming, either does not understand the basic science, or is being deliberately misleading."

    Bias.

    Increase in Carbon dioxide does not assure Global Warming. There are more variables to the equation.
    =========================================
    Carbon dioxide certainly does cause global warming because if atmospheric carbon dioxide increases then the world will become warmer than it would otherwise be, and this can't not happen (not without changing the laws of physics). It's certainly possible for another forcing to have a cooling influence which counteracts the warming from increased carbon dioxide, such that there is no net warming, but the warming influence of increased carbon dioxide is still there (if it wasn't, then in that situation there would be global cooling).

    So, there is no valid sense in which increasing atmospheric carbon dioxide doesn't cause global warming. It does, and it has to, regardless of what other forcings and feedbacks are in play.
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  36. Regarding #33,
    OK, I wondered if you were talking about condensation of water vapor, but I still think you are not considering the wavelengths outside of what the human eye can detect. 'White' just means that all 3 flavors of our cones are highly stimulated, but each flavor of cone is optimally responsive on a fairly narrow band. The human eye is actually pretty limited; we can't even tell the difference between a red-green brown and a blue-orange brown. But, I digress. Clouds don't treat all wavelengths the same; as evidenced by people getting sunburned by UV on a cool and cloudy day.

    How does the air warmed by your engine cool? Same as warm air has always cooled since the earth was formed; but ultimately, energy only leaves the earth, atmosphere included, through radiative processes.
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  37. Chris G at 00:51 AM on 1 July, 2010
    #32

    That is a good question, but it sounds like you are implying that hydroelectric power is trapping heat, since you cant get something for nothing. If the net effect is zero, where is the energy from a dam coming from? Are you now saying that dams are causing global warming as well?
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  38. RSVP - Duh, when your radiator heats the air it cools by conduction, convection, and (via heating ALL of the air in that space) heating CO2 and water vapor, which can indeed emit their energy as IR.

    Come on, RSVP - I've read your posts, you know this stuff! And you know (or should by now) that total waste heat from industrial (and automotive) processes represents 1/10,000 the energy of the CO2 driven radiative imbalance. It has no significant impact on global warming.
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  39. Chris G
    The engine cools through intensely forced convection that is not found anywhere in nature.
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  40. KR
    <>

    As was sited way above, water vapor and CO2 only make up about 3% of the atmosphere. AGW rests on the asumption that the other 97% does not emit IR very well. That is what our engines are warming.
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  41. Very nice text. The radio analogy is definetely one I will use when explaining the frequency spectrum to other lay people.
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  42. Chris G - latent heat is estimated at ~76-78 W/m^2 (can't remember exact number off the top of my head) from liquid to vapor form; evaporated from surface water and ground moisture. This gets deposited primarily at the condensation point in the lapse rate where clouds form - no energy is deposited by condensation until the bottom of the cloud, when the temperature has dropped enough. Thunderstorms and major convective events (hurricanes) can draw water vapor high into the troposphere and even in extreme cases the lower stratosphere, but generally the energy movement is to the middle troposphere.

    I wrote something quite wordy about thunderstorms, lapse rates, and the like, in a previous topic, and now I can't find it! Oh well...

    Given that the IR pathlength is on the order of 10's of meters before absorption/emission events, this certainly moves the heat into the atmosphere, warming it.

    IR radiation to space occurs when CO2 density and total water vapor (along with total pressure) drops low enough to permit it, in the stratosphere, hence the GW phenomena of a warmer troposphere and colder stratosphere.
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  43. Very true, RSVP - and that 3% is the 'antenna' that the energy of the entire mass of air can radiate IR from. Or receive upon, for that matter.

    And as the CO2 and water vapor lose/gain energy from IR, thermal collisions with the rest of the air mass spread those effects throughout, lowering or raising the temperature of the entire air mass.
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  44. #37,
    Umm, no, I don't see a connection between what I said and what you said.

    Regarding #39,
    Nothing in nature burns? Nothing in nature gets hot? If greater than zero things get hot in nature, what would be the accumulated heat over, say, 4.5 billion years?

    #40,
    Gases absorb and emit at the same wavelengths, specific to each gas. If 97% of the air does not emit IR, it doesn't absorb it either; it passes through unaffected.

    KR, thanks for the detail. I think got the gist of correcting myself at #34. I'm confident you know this, but I'd think the distance traveled would be dependent on the density of the gas. The density of air diminishes rapidly with altitude; so, I suspect it is a mistake to use a fixed value for distance traveled.
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  45. Absolutely right, Chris - the distance varies with the number of GHG molecules per unit volume. I was typing quickly (carelessly) there about the lower atmosphere; mean free path length increases as pressure drops.
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  46. "intensely forced convection that is not found anywhere in nature."

    What a convoluted way to make a false assertion for the sake of argument. Check out these pictures, the convection in them dwarfs any engine cooling system. They routinely contain vertical wind shear in excess of 60 mph.

    http://www.mesoscale.ws/pictures/structure/
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  47. Chris G - if you're interested, I found a little bit I wrote on lapse rate, latent heat, thunderstorms, etc, over on "CO2 is not the only driver of climate". This was in the context of a conversation on the relative importance of ground driven convection and latent heat as energy transfer mechanisms, with a background discussion of the (much larger) radiative energy flows.
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  48. < #37,
    Umm, no, I don't see a connection between what I said and what you said.>>

    Clarifying:
    Perpetual motion does not exist. Hydroelectric delivers energy. It is not a perpetual motion machine. The guzins being the Sun. The guzouts being Earth cooling.

    Meanwhile man is tapping into this "machine". The sun continues to shine as always (guzins doesnt change). The guzout is constant (or per AGW now working less efficiently, but this has nothing to do with my clarification). Somehow in this equation, energy is comimg from somewhere, but according to AGW its getting hotter all the time because of CO2. We have left the realm of electromagnetics, quantum physics and are now only talking about bean counting.
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  49. To Chris G (again)
    "Regarding #39,
    Nothing in nature burns? Nothing in nature gets hot? If greater than zero things get hot in nature, what would be the accumulated heat over, say, 4.5 billion years?"

    Please do not misquote me. I did not say that.

    I was referring to my cars radiator. An aluminum heatsink with thousands of orifices where air passes through cooling water heated by my engines water jacket.
    This is Man's invention. So are nuclear power plants, and all other forms of boiler burners etc.

    These are in addition to the heat that already exists due to the sun warming us as it should. This "small" amount of heat is heating the air which as I said does not emit IR. Now you are telling me that the GHG are acting as an antenna to get rid of this radiation. I am listening. I would like to hear more about this.
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  50. Woops
    Very sorry about that Chris G. It was KR who explains that CO2 acts as an antenna for other gases.
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