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Plass and the Surface Budget Fallacy

Filed under: — raypierre @ 13 January 2010

RealClimate is run by a rather loosely organized volunteer consortium of people with day jobs that in and of themselves can be quite consuming of attention. And so it came to pass that the first I learned about Gavin’s interest in the work of Plass was — by reading RealClimate! In fact, David Archer and I have a book due to appear this year from Wiley/Blackwell (The Warming Papers), which is a collection of historic papers on global warming, together with interpretive essays by David and myself. Needless to say, we pay a lot of attention to the seminal work by Plass in this book. His 1956 QJRMS technical paper on radiative transfer, which is largely the basis of his more popular writings on global warming, was one of the papers we chose to reprint in our collection. In reading historic papers, it is easy to fall into the trap of assuming that investigators of the past are working on the basis of the same underlying set of assumptions in common use today. Through a very close reading of the paper, David and I noticed something about the way Plass estimated surface temperature increase, that Gavin and all previous commentators on Plass — including Kaplan himself — seem to have overlooked.

These days, it is fairly common knowledge that determination of surface temperature change requires simultaneous satisfaction of the top-of-atmosphere energy budget and surface energy budget, and that in most circumstances it is the top-of-atmosphere budget that plays by far the leading role. This is one of the many things that Arrhenius got spot-on right in his conceptual framework for computing surface temperature. His computation explicitly takes both balance requirements into account, though substantial inaccuracies were introduced because the onerous computations involved in solving the model pretty much restricted him to a one-layer representation of the atmosphere. Later workers improved on Arrhenius by introducing multiple layers and more accurate spectroscopy, but did not always note the importance of satisfying the top-of-atmosphere balance. I think it seems natural to most people to assume that if one is interested in surface temperature, the surface budget must be the most important thing to look at. Plass, for all his brilliance in computing the radiative effects of CO2, was one of the ones who was led astray by this fallacy.

Since discussions of radiative forcing today are almost invariably based on top-of-atmosphere budgets (or at least top-of- troposphere budgets, which are almost the same thing), it is natural for the modern reader to assume that when a paper quotes a radiative forcing, it must be a top-of-atmosphere forcing. This is what Gavin assumed, but a close reading of the 1956 QJRMS paper shows that this is not, in fact, what Plass was talking about. In that paper, Plass does not get around to turning his voluminous radiative calculations into a surface temperature change until nearly the last page of the paper, and when he does, he spends barely a page explaining the reasoning.

The radiative forcing Plass quotes is actually the increase in downward infrared radiation to the surface, which you get if you double CO2 while holding the atmospheric temperature fixed . This back-radiation increases because increasing the concentration of a greenhouse gas makes the atmosphere a more efficient emitter of infrared radiation, at least up to the point where the lowest bits of the atmosphere emit so well that they essentially have become a blackbody, whereafter the emission to the ground can no longer increase unless the air temperature changes. For Earthlike conditions, the emission from CO2 is nowhere near saturated in this sense (see this post ) , so Plass was entirely correct in inferring an increase in the back-radiation, at least for a relatively dry atmosphere. Adding CO2 to the atmosphere is a bit like turning up the dial on a heat lamp you are lying underneath.

It is in the final stages of the calculation that Plass went wrong. He assumed that the surface would get rid of the extra infrared radiation it was receiving by heating up until it was able to radiate away the excess. This reasoning ignores the fact that radiation is not the only means of exchanging heat between the atmosphere and the surface. There are also turbulent exchanges, including evaporation, and these would tend to limit the surface warming to values far less than the values Plass estimated. Further, when the lower atmosphere is warm and moist, such as in the tropics, the great infrared opacity of the large quantity of water vapor tends to limit the direct effect of CO2 on back-radiation into the surface, which further limits the surface warming if the air temperature is held fixed as Plass did. To be fair, Plass does include a sentence implying that he was concerned about the portion of the retained flux that exited through the top of the atmosphere, but even if one gives the most generous interpretation to what might have been meant by this statement, there is no way to make a consistent calculation out of it, given the use of the surface back-radiation as radiative forcing.

The way the greenhouse effect really works is that adding CO2 reduces the infrared out the top of the atmosphere, which means the planet receives more solar energy than it is getting rid of as infrared out the top. The only way to bring the system back into balance is for the whole troposphere to warm up. It is the corresponding warming of the low level air that drags the surface temperature along with it — an effect left entirely out of Plass’ calculation.

A more quantitative discussion of the way all this works can be found in The Warming Papers, and a yet more advanced discussion of such things can be found in Chapter 6 of my book Principles of Planetary Climate (which at long last has been shipped off to Cambridge University press, animula vagula blandula)

In point of fact, Plass did compute the top-of-atmosphere radiative forcing due to doubling or halving the concentration of CO2. The result is plainly shown in the rightmost graph of his Figure 7, where he shows the vertical profile of upward and downward flux for three different CO2 concentrations. Reading the values from the top of the graph, I get that Plass computes a 3.2 Watt per square meter reduction in the outgoing radiation for a doubling of CO2. This is really quite close to the modern value. Plass does not mention this number, or its importance, anywhere in the text, however. Still, it would be fair to give Plass the credit for the first calculation of top-of-atmosphere radiative forcing using correct modern radiative physics. Though he did not make good use of the calculation himself, the methods he introduced are largely the same as those used by Manabe and Wetherald in 1967, who were the first to put together correct spectroscopy with a correct framework for computing surface temperature, adding in accurate water vapor spectroscopy and the effects of convection along the way.

Thus, while Plass made seminal contributions to radiative transfer, his actual estimate of surface temperature increase cannot be regarded as an improvement over Arrhenius. Plass had better spectroscopy than Arrhenius, but a framework that would not give the right answer no matter how good the radiative transfer was. The point of all this historical deconstruction is not to poke fun at Plass or detract from his contributions. Theories do not spring from scientists full-formed like Athena from the head of Zeuss. Science often proceeds through a series of errors and corrections, and those who move the ball forward are in the thick of this process even if they have made some mistakes. The point is that our current understanding of global warming rests on the shoulders of some of the greatest giants of physics of the past century or more, and myriad lesser but still substantial intellects as well.

So, when push comes to shove, was Plass a Hedgehog or a Fox? The answer is: a bit of both. With regard to computing the radiative fluxes due to CO2, Plass was a true hedgehog — he knew that one thing really, really well, and that had a lasting impact on our science. But in his Tellus article, he also showed himself to be quite a fox, in that by knowing (and explaining) many independent lines of thinking, he helped to revive attention to the wide-ranging importance of CO2 in climate. You could say he was not enough of a fox to have also absorbed the lesson of the importance of top-of-atmosphere balance, known already to Arrhenius. But also, you could say that if you’re going to be a hedgehog and pick one thing to be the central organizing principle of your world view, it had better be a pretty darn universally important thing to know. If you’re going to be a climate hedgehog, the constraint imposed by top-of-atmosphere radiation balance would be a pretty good place to hang your hat.


230 Responses to “Plass and the Surface Budget Fallacy”

  1. 51
    Hank Roberts says:

    Ok, my apology to Jerry Steffens.

    You’ve actually been asked that kind of question by students at the college level?

    If I were asked “Why should the act of adding extra molecules of certain gases create energy?” I’d reply by asking “Who told you that adding extra molecules can create energy?” — if they’re confused about “turning food to energy, I’d point out that a blanket will keep a hot brick or a hot water bottle longer too.

    Everyone knows a good down sleeping bag keeps you warmer than a thin one.

    Any snow camper learns the criterion for a really good sleeping bag — inside you’re warm, but the nylon outside layer of the sleeping bag has to be below freezing, so the moisture from the body leaves its warmth inside the down layer but then freezes, making frost on the outside of the bag (instead of making the bag damp and cold).

    Kind of like the troposphere/stratosphere transition for water vapor.

  2. 52
    Jaime Frontero says:

    gavin -

    in re your response to #43…

    Michael Coffman – the editor of the publication you linked to (“Discerning the Times”) – has an interesting history, when you search on him at exxonsecrets.org.

    These folks do get around – politics, faux science, religion – don’t they? You’d think they’d have some difficulty with their finances, what with jumping from one job to another all the time, but I guess not…

  3. 53
    Richard Schwartz says:

    There is an important feature concerning the basic science of “greenhouse” gas warming which has received little if any notice in most discussions. The question is, how and why does the increasing infrared energy density in the atmosphere get transformed to thermal energy (increased gas temperature)? As I understand it, the fundamental physics of the issue is that the radiative lifetime of greenhouse molecules is much greater than their mean collision times with atmospheric molecules, at least in the troposphere. Thus an excited molecular state created by absorption of an infrared photon is more likely to deexcite by bumping into a nitrogen or oxygen molecule (collisional deexcitation)than by spontaneous radiative emission. This imparts kinetic energy to the nitrogen and oxygen molecules, which of course is the same as increasing the thermal energy of the ensemble. The basic key is in the shorter collisional time compared with the longer radiative lifetime of greenhouse gases. Without this, there would be no “greenhouse” effect. Of course one has to work out the detailed balance of all of the radiative and collisional processes at work in a gas, and indeed this is an important part of the history of atomic and molecular physics.

    [Response: This kind of assumption is essentially wrapped into the assumption of local thermodynamic equilibrium, which is what allows us to use Kirchoff's Law of Radiation (absorptivity equals emissivity). Most strat/trop climate people hardly ever think of the issue you mention, because once you are using Kirchoff's Law you don't have to think about the details of radiative lifetime. In the far upper atmosphere, LTE breaks down and radiative transfer becomes a whole different ball game. The techniques for dealing with radiation in that case are well known to people that work with the exosphere and thermosphere, but there is surprisingly little interaction between that community and folks working further down. I have had to learn something about the far upper atmosphere stuff in order to deal with the problem of atmosphere loss from extrasolar planets, but I'm still working my way up the learning curve there. --raypierre]

  4. 54

    Jerry Steffens, re #48, in your #38 you reference words of mine of #33. To clarify, I was not asking a question; I was attempting to point out that the ocean effect, that I described previously as a control system that attempts to null out the surface temperature, would take heat from the surface and hold it internally in the ocean. In doing so it would lower the surface temperature. This would act to prevent the top of the atmosphere from reaching equilibrium, thus violating the fundamental premise of the modeling.

    Hank Roberts #40, your link shows a clear diagram that shows exactly zero energy going into the ocean. This denies vertical mixing that would draw heat down. And the fallacy of this is my point.

    If heat goes into the ocean this will keep the surface temperature lower and the top of the atmosphere will not reach equilibrium, and yes, the globe will continue to warm up, only the surface temperature will not show it. Under this model, this warming will not stop at a surface temperature point where equilibrium is reached for a given CO2 density.

  5. 55
    Dave Werth says:

    “The way the greenhouse effect really works is that adding CO2 reduces the infrared out the top of the atmosphere, which means the planet receives more solar energy than it is getting rid of as infrared out the top. The only way to bring the system back into balance is for the whole troposphere to warm up. It is the corresponding warming of the low level air that drags the surface temperature along with it.”

    I agree with Ron Taylor. That is clear and concise. The sort of simple idea that “skeptics” might be able to understand. But it made me wonder, if you could to reduce the CO2 level in the lower atmosphere, to the top of the troposphere or stratosphere say, back to the 280 ppm level but kept the situation in the upper atmosphere at the 390 ppm level would it change the warming at the surface much or is it the TOA changes that do all the driving ultimately?

    [Response: I'm not sure if this is what you are getting at, but if you could take all the CO2 in the atmosphere and concentrated it in a layer near the ground (which would be about 2 meters thick) you would eliminate the CO2 greenhouse effect. The atmosphere would then cool down enough that most of the water vapor would be lost, too, and then the oceans would freeze and you would turn into a snowball. Given the strong vertical mixing in the troposphere and the lack of any significant sink of CO2 interior to the atmosphere for Earthlike temperatures, there is no plausible way to maintain such a vertical CO2 gradient, though. It's still an interesting thought experiment. --raypierre]

  6. 56
    Robert says:

    To 45. And 47.

    He is left-wing because he thinks global-warming is a conspiracy of the Trilateral Commission, a corrupt government/industry think-tank. He writes for and is linked to Project Censored.

    http://www.projectcensored.org/top-stories/articles/22-obamas-trilateral-commission-team/

  7. 57
    Thomas says:

    A bit off topic but I think we are getting hammered by the well publicized cold snaps this winter. You know the extraordinary western European cold snap happening at the same time as the US southest is having a highly anomalous cold snap as well. So it is getting hard to deflect the comments that the whole world has dramatically cooled off. I try to do my part, mentioning that global circulation has equator to pole flows as well as pole to equater flows of heat, and they should be roughly balanced out (i.e. if some regions are experiencing anonalously cold weather others are warm -they just don’t make the news). So in the interest of damage control, I think we need a post about this extraordinary winter. Where are the hot spots, and where are the cold spots? Is the supposedly partial diversion of the gulf stream to west Greenland real? If so is it serious?

  8. 58
    Aaron Lewis says:

    “He who knows only his own generation, remains alwas a child”.

  9. 59

    Talking of communist stooges and the like, his pottiness Chris Monckton is shortly to visit Australia, charging $20 at most locations to hear him talk. I hope he continues with his current rant about how climate change is a communist plot to establish world government.

    It doesn’t take much imagination to see the implausibility of all those Marxist revolutionaries deciding to cease and desist from running countries with nuclear arsenals and become climate scientists instead. Or do you guys keep a few SS20s at the back of the lab?

  10. 60
    Silence says:

    @#43

    I think the article does have some good points about the urban heat island effect. Maybe man is causing global warming, but in a different way…

    According to the EPA, http://www.epa.gov/hiri/, urban heat island effect can cause temps to increase from 1.8 – 5.4 F in the day and up to 22F at night.

    Does anyone know if there is a global map of where temperature data stations are located [edit]? It would be interesting to see if the models would be any different.

    Maybe corrections have been made for temp stations located near cities, but if they have been, they should be made public so all scientists can be certain how the scientists who have collected their data have arrived at their models and conclusions.

    [Response: All of this stuff has been discussed and researched for decades. See the data here, read about corrections for UHI here, and discussions here. - gavin]

  11. 61
    Edward Greisch says:

    raypierre’s response to 37: Yes, I think the complete subject would be heavy going once you put in the math and the complications, like convection. Can you make equations appear like on the old fashioned blackboard in another post and ease us into it gently, please? I am 40 years rusty. Just a tiny bit more could be interesting.

    I thought I saw over 100 comments already. What happened to them?

    [Response: It's actually not all that complicated. Convection is just handled by adjustment of the temperature profile to an adiabat, not by fluid dynamics. But RealClimate is not really the place for that level of detail. If you want that, you should buy Principles of Planetary Climate when it comes out in June or so :) --raypierre ]

  12. 62
    Molnar says:

    Thomas (57):

    Yep, those damn cold snaps, always at wrong places, eh? :)

    http://www.skepticalscience.com/Where-did-global-warming-go-heres-where.html

    Philip Machanick (59):

    What makes it even more funny is that the communist establishment hated everything “environment”, because the economy was mostly oriented towards polluting heavy industry.

  13. 63
    Completely Fed Up says:

    Jim Bullis: “Hank Roberts #40, your link shows a clear diagram that shows exactly zero energy going into the ocean. This denies vertical mixing that would draw heat down.”

    It doesn’t deny vertical mixing.

    It just doesn’t take it into account.

    This could be for the same reason we don’t take CO2 sequestration by rock weathering into account for the 100 year forecasts. Over 100 years, it’s not a factor. Indeed, even the same reason why we have a “flat” ruler to measure tabletops rather than a curved one to match the known fact that the earth is a sphere.

    So can you provide any proof that the lack of vertical mixing changes the conclusion?

  14. 64

    By the way, I don’t think that your comment in #41 is a particularly good analogy — in your example, the source of energy is INTERNAL(body heat), whereas the source of energy for the earth-atmosphere system is EXTERNAL. A sharp student would be sure to point that out.

    Jerry, quite so… and an even sharper student would point out that the heat becomes internal the moment sunlight is absorbed by the surface. The situation would be just the same (well, except for a myriad of details) if there were no Sun and all of the heat was geothermal.

    Actually there is a lot in common between the study of planetary and stellar atmospheres. Many denialists don’t realize that they’re also trying to abolish most of astrophysics. At least Ian Plimer is explicit about it ;-)

  15. 65
    Ray Ladbury says:

    Robert @56,
    OK, you obviously are not familiar with LaRouche. He went so far right that he came back around on the extreme left.

    File under nutjob conspiracy theorist.

  16. 66
    Ray Ladbury says:

    Richard Schwartz@53

    OK, think about it this way. In thermal equilibrium, you tend to have the same amount of energy in all modes of a molecule–translational, vibrational, rotational, etc.–that aren’t frozen out. Now dump some energy into one mode–vibrational. It has to find its way into the other modes, right? The way the excited molecules do so is by imparting energy to molecules with which they collide. Remember, this is a vibrational mode–the atoms are moving wrt the center of mass and so can impart kinetic energy. CO2 has a very long radiative lifetime–about a microsecond, so it is particularly efficient at thermalization.

  17. 67
  18. 68

    Thomas #57: this picture of December temperature anomalies from http://nsidc.org/arcticseaicenews/index.html is a good answer. Note the mix of abnormally hot (especially Arctic and Greenland) and abnormally cold areas.

  19. 69
    Bill says:

    when do we consider that man-made CO2 forcing became apparent ?

    [Response: It is very difficult technologically to detect the direct effect of CO2 increases on the spectrum of outgoing radiation, but that's not a particularly critical thing do do as there is essentially no doubt about the basic radiative physics, which can be confirmed perfectly well in laboratory conditions. For observations, the main issues concern detecting cloud feedbacks. The human imprint on temperature (via increase in long-lived greenhouse gases) became detectable between 1970 and 1990. That is a more important confirmation, since it involves water vapor and cloud feedbacks. ---raypierre]

  20. 70
    Bill says:

    and how are these latest posts on topic , I would expect to see some consistency….At least I was trying to seek opinion and information from the expertise on here

  21. 71

    CM — thanks! That really helps!

    I couldn’t get to the Kushner et al. reference. Do you have a citation?

  22. 72

    Alexandre,

    Thanks for the Fu et al. reference!

    I have extensive tables of CO2 absorption coefficients. You can derive them for 102 bands from the tables of Houghton et al. (“The Physics of Atmospheres,” 2002); I have a set of 54 I basically compressed from his. If you want a simpler (fewer bands) set, Essenhigh (2001) gives the information listed on this web page:

    http://BartonPaulLevenson.com/Saturation.html

    Let me know if you want the larger sets. I also have figures for water vapor, ozone, methane, molecular oxygen, and ice and water clouds. Many tables use different units for absorption coefficients, but translating is fairly easy once you know the relevant equations.

    [Response: And I wrote a Python interface to the HITRAN database, which makes it easy to extract coefficients for any gas. That's one of the bits of software I'm cleaning up for release in connection with Principles of Planetary Climate. It will be on my own web site, as well as the Cambridge University Press web site. --raypierre]

  23. 73
    Dappled Water says:

    #31 BPL – some studies that may be of assistance, I’ve only glanced over them as yet :

    - “Cooling of the Arctic and Antarctic Polar Stratospheres due to Ozone Depletion” – Randel & Wu 1998
    http://www.met.sjsu.edu/~tesfai/RESULTS/Journals/Randel%20and%20Wu%201999a.pdf

    - “Contributions of External Forcings to Southern Annular Mode Trends” – Arblaster & Meehl 2005
    http://cawcr.gov.au/bmrc/clfor/cfstaff/jma/arblaster_meehl_sam.pdf

    - “Observed poleward expansion of the Hadley circulation since 1979″ – Hu & Fu 2007
    http://hal-insu.archives-ouvertes.fr/docs/00/29/63/53/PDF/acp-7-5229-2007.pdf

    - “A Consistent Poleward Shift of the Storm Tracks in Simulations of 21st Century Climate” – Yin 2005
    http://www.cgd.ucar.edu/cas/jyin/IPCC_paper_GRL_Jeff_Yin_final.pdf

  24. 74
    CM says:

    Sufficiently sublime nuttery transcends right and left. Let’s leave it at that.

  25. 75
    Completely Fed Up says:

    “Bill says:
    14 January 2010 at 6:31 AM

    when do we consider that man-made CO2 forcing became apparent ?”

    I don’t think you consider it apparent and unwilling to accept anything could do so, so the answer could well be “never”.

    In the 80′s there was almost universal rebuttal of AGW as true “because there is no proof there is warming”. Nowadays, you see a lot of posts saying (with the same level of truth: practically none) “nobody denies that it’s warming, just its cause”. That change came about in the 90′s.

    None of those claiming they don’t disagree with the warming trend, just that CO2 caused it haven’t managed to do any work that succeeds in explaining the warming trend however.

  26. 76

    Re: #67 and preceding–

    Although this is a repetition: it may also be helpful to refer folks to the AMSU lower-trop values for the year to date, helpfully presented by Roy Spencer. (BTW, I appreciate that he isn’t doing anything to obscure this data on his site, though at present it’s not particularly helpful to the view he wishes to promote.)

    http://discover.itsc.uah.edu/amsutemps

    I stress that “it’s just weather,” but even the weather doesn’t currently offer support to the “it’s cooling” meme, if you look at the big (ie, global) picture.

  27. 77
    CM says:

    BPL #71, sorry, messy DOI. Reference follows. Again, you need to check for yourself if this is what you’re looking for; I’m just guessing.

    Kushner, P.J., I.M. Held, and T.L. Delworth, 2001: Southern Hemisphere Atmospheric Circulation Response to Global Warming. J. Climate, 14, 2238–2249.

  28. 78
    Jim Ryan says:

    Just wanted to bring your attention to this apparently excellent book. For some reason your site maeks the review text as spam.

    BOOK REVIEWED-Climate Cover-Up: The Crusade to Deny Global Warming
    by James Hoggan with & Richard Littlemore

  29. 79
    Geoff Wexler says:

    If you want that, you should buy Principles of Planetary Climate when it comes out in June or so

    When I enquired, CUP predicted that it would take about 9 months.

    Questions:

    1. This back-radiation increases because increasing the concentration of a greenhouse gas makes the atmosphere a more efficient emitter of infrared radiation

    This is because the number of radiating centres will have increased. But what about the radiation per greenhouse molecule? If most of this will be from molecules at local thermodyamic equilbrium then this will rise as a result of tropospheric warming. From what you say , Plass has ignored this term because he has held the temperature fixed. Is that significant?

    2. simultaneous satisfaction of the top-of-atmosphere energy budget and surface energy budget, and that in most circumstances it is the top-of-atmosphere budget that plays by far the leading role.

    I don’t quite follow what ‘leading role’ means if both boundary conditions have to be satisfied under steady state conditions. Does this mean that there are some approximate solutions lying around for which only one of the two conditions is satisfied and that these can be compared for accuracy?

  30. 80
    Completely Fed Up says:

    Geoff: “I don’t quite follow what ‘leading role’ means”

    The energy has to leave the planet.

    There’s a vacuum in the way, so how the energy gets out is raidation. And that comes from TOA by the definition of TOA.

    You could lose energy by mass loss too (but only the amount of Kinetic Energy the leaving particle takes with it), but I don’t think that’s a big player here.

  31. 81
    Alexandre says:

    BPL #72

    I do want the larger set, especially for CO2. If it´s easier to use an email, you can use tiburcio43 -at- gmail -dot- com

    I´m no scientist, I just want to learn more (your website and David Archer´s “offering” have helped here) – and possibly help to inform others.

    Raypierre – I´ll keep an eye on the Cambridge University´s website. Thanks.

  32. 82
    Timothy Chase says:

    Geoff Wexler wrote in 79:

    I don’t quite follow what ‘leading role’ means if both boundary conditions have to be satisfied under steady state conditions. Does this mean that there are some approximate solutions lying around for which only one of the two conditions is satisfied and that these can be compared for accuracy?

    completely fed up wrote in 80:

    The energy has to leave the planet.

    There’s a vacuum in the way, so how the energy gets out is raidation. And that comes from TOA by the definition of TOA.

    That’s part of it. The other part is that the top of the atmosphere responds first. It cools because less radiation is making it to the top. Then the lower atmosphere warms and expands (remember — the lower atmosphere has a great deal more mass so it will take longer to warm up), then this will cause the outer atmosphere to expand and cool — with additional drag on satellites. We are already picking up some of the latter.

  33. 83
    John E. Pearson says:

    My elementary understanding of the basic physics is that increasing atmospheric CO2 results in the TOA shifting upward. (1)Is this because the partial pressure of CO2 at fixed altitude increases?) Then, the increase in the altitude of TOA results in the temperature at TOA being lower thus decreasing the outbound radiation thus warming the planet. If this is fundamentally wrong please correct! (2)There must be a minimal mathematical model that captures these effects qualitatively? (3)What is the precise definition of “TOA”?

  34. 84
    gary thompson says:

    regarding the followign email – why would Jones not want you (gavin) to be critical of a paper that he was giving you an advanced look at? on the surface this appears to be one scientist telling another scientist not to look critically at a paper and instead gloss over the errors. surely that is wrong. please clarify.

    http://www.eastangliaemails.com/emails.php?eid=883&filename=1211462932.txt

    [Response: You are reading too much into this. Our interest was in the context not the specific content - the relevant blog post is "On buckets and blogs", pointing out that lots of people who should have known better got the story all wrong. Where did anyone 'gloss over the errors'? (and what would they even be?). You seem to think that science is some kind of blood sport rather than a collaborative enterprise. It is not. - gavin]

  35. 85

    Jim Ryan, yes–I’ve also reviewed it here. It’s a bit of an eye-opener for those who think that denialism is a spontaneous phenomenon.

    Climate Cover-Up is readily available on Amazon. (There’s a link from the review, even.)

  36. 86
    Hank Roberts says:

    John, it’s a FAQ; the short answers you get when people retype from memory brief ideas about the answer will always lead you to more questions. Short answers in a blog thread don’t give you the whole picture, they just drag on and on.

    If you read the FAQ at the “Start Here” button, and the first link under Science, you’ll have them all in one place already answered. At least then you can refer to those and specify what part of the explanations you don’t understand — and they can be improved for the next seeker.

  37. 87
    Jaime Frontero says:

    @ 82:

    I’ve been wondering about that:

    “…then this will cause the outer atmosphere to expand and cool — with additional drag on satellites. We are already picking up some of the latter.”

    So on one hand, LEO becomes much less usable, requiring greater emission of some seriously bad rocket exhaust (discounting LOX/LH) to reach higher orbits…

    …but on the other hand, our little problem with space debris (the bulk of which is in LEO) will correct itself, as the tenuous drag of the gasses at that altitude increases.

    Given the nature of many rocket fuel exhausts, the quantities (and concentrations) involved, and how these gasses are introduced into all levels of the atmosphere, this doesn’t seem to be a particularly good trade-off.

  38. 88
    Completely Fed Up says:

    re:82 I would count that more as “it’s more complicated than just TOA lets radiation out because pressure changes at TOA when the lower levels warm up”. The basic stance is still: the TOA has to let the energy go.

    But your detail is correct.

  39. 89
    Ray Ladbury says:

    Gavin’s in-line@84 says “You seem to think that science is some kind of blood sport rather than a collaborative enterprise. It is not.”

    I think of it as the most collaborative of blood sports. It certainly is proof that a human activity can be simultaneously very competitive and cooperative.

  40. 90

    Re: #84 & inline response:

    My take, on the face of it, would be that Gary is suffering from confusion about context: the interest in an advance look was in Gavin and Dr. Mann helping to keep the “take away” message straight in the midst of whatever media interest turned out to occur. Hence I conclude that the offer not to be “critical”–from the email preceding it’s clear there was no request from Dr. Jones to avoid criticism–is meant to apply to media comment, not to normal scientific scrutiny.

    After all, the paper was just about to come out; peer review had taken place already and only a little last minute tinkering with wording was still going on. It was way too late for “scientific” criticism to offer any (pre-publication) benefit. (Of course, “outside” scrutiny really begins upon publication.)

    If I’m misunderstanding this, please correct me.

  41. 91
    Geoff Wexler says:

    #79, #80 and #82

    Of course the reference to the leading role played by the atmospheric budget at the top of the atmosphere is not problematic e.g. when trying to solve the problem. For example, as explained in the article the radiative imbalance at the surface would be a lousy starting point for a calculation. It could even lead to Plass type errors. Hence the conventional definition of forcing is located at the top of the atmosphere.

    My question was/is based on the juxtaposition of that reference with the earlier one stating that you need to satisfy both boundary conditions [to obtain the steady state solution]. I should imagine that the problem would be indeterminate if only one boundary condition were to be imposed.

    #82 which refers to the dynamics, is interesting, but is already in the article.

    My comment does not refer to the physics but to the maths i.e. to a possible (literal) interpretation of a sentence that appears to state that the solution is more sensitive to the violation of one boundary condition than to the other.

    [Response: It's true in the mathematical sense that you need to satisfy both boundary conditions. My statement was not meant to imply that you can violate the surface balance condition. What I meant was that you can infer the surface temperature change without knowing much about the details of the surface energy balance. That is so because in most circumstances the coupling between the surface temperature and the lower tropospheric temperature is so tight that the two temperatures simply move in concert. There are exceptions to this, and you can get some modification of warming or cooling through changes in the surface energy budget. The most important example of that occurs when land dries out, eliminating the evaporative cooling term. But over the oceans and moist land, which is most of the planet, you can get a very good estimate of surface temperature changes by just assuming the surface temperature increases with that of the lower troposphere. Quantitative examples are given in my earlier post, "A Busy Week for Water Vapor," in The Warming Papers, and in the surface budget chapter of Principles of Planetary Climate. Sorry y'all have to wait six to nine months for those, but that's just the reality of the publishing industry. I thought seriously of just giving the book away for free on the web, but there are important advantages of having a publisher involved, particularly with regard to distribution, quality of the hard copy, and professional layout. All that costs them money, which is accounts for almost all of the cost of CUP books. --raypierre]

  42. 92

    #40 Hank Roberts,

    You provided the link here repeated,

    http://chriscolose.files.wordpress.com/2008/12/kiehl4.jpg?w=480&h=350

    It shows zero heat going into the ocean.

    Is there not some curiosity about how the increased ocean heat content of 10×10^22J could have occurred over the last 25 years or so with zero heat going into the oceans? The heat content increase is shown at:

    http://www.realclimate.org/index.php/archives/2009/12/updates-to-model-data-comparisons/

    Teacher Jerry Steffns (#38), what’s wrong with this picture?

  43. 93
    John E. Pearson says:

    86: Hank, the first link under science is the IPCC report. Presumably you meant something else?

  44. 94
    Ike Solem says:

    Interesting article, but why not mention of the satellite that wasn’t launched, or discussion of current plans – rumor has it that Triana/DSCVR was taken out of mothballs and prepped for launch in November (ten years late)?

    That’s related to this comment plus response:

    How reliable and detailed are our measurements of top-of-atmosphere energy budget? Can we say for certain that the Earth has been consistently receiving more energy than it radiates away to space in recent years or decades? … Comment by Icarus — 13 January 2010

    [Response: The satellite TOA budgets are not yet accurate enough to do this sort of thing, or at least not stable enough over time. Hansen argues that monitoring the ocean heat storage is a more feasible way to get at the same issue, since the atmosphere itself comes into equilibrium quickly, so that most of the TOA imbalance is reflected in changes in the ocean heat storage... --raypierre]

    Obviously, parking that satellite out at L1 would give real-time measurements of radiation balance, solar output, and so on, and would have given us a nice ten-year record of the Earth’s radiation budget. I know you guys are not unaware of this – but why no mention?

    Is it because this failure to launch is yet another example of institutional failure in the U.S. scientific community? One largely due to the politicization of science by corporate fossil fuel interests and their paid-off politicians – although that wouldn’t be possible without the compliance of numerous fellow travelers in academic positions, would it?

    Yes, it’s a touchy topic, I know.

    P.S. “Icarus” & Gigner – the Greeks didn’t know about the vertical thermal structure of the atmosphere – in fact, you’d crash because the wax would freeze up and lose elasticity, cause the wings to crack – not due to melting.

  45. 95
    Hank Roberts says:

    > blood sport

    Beloved of bloggers and their audiences (grin).

    For your amusement:

    ___________
    “…. my Climategate posting has been chosen as one of the “50 Best Science Blogging Posts of the Year”* by an elite cabal ….

    Just to be clear: we’re talking about that rant in which I claimed that science depends at least partially on the pettiness and vindictiveness of scientists, and in which I proclaimed my fond desire to see the Pope immersed in nitric acid. One of the best science posts of the year, tube-wide.

    I don’t understand it. I write about space vampires. I haven’t published a peer-reviewed technical paper in more than a decade. And yet, these troublesome vestiges of credibility continue to haunt me….”

    — Peter Watts
    http://www.rifters.com/crawl/?p=1002
    —————
    * http://scienceblogs.com/neurotopia/2010/01/announcing_open_lab_2009.php#more

  46. 96
    Martin Vermeer says:

    That’s part of it. The other part is that the top of the atmosphere responds first. It cools because less radiation is making it to the top. Then the lower atmosphere warms and expands (remember — the lower atmosphere has a great deal more mass so it will take longer to warm up), then this will cause the outer atmosphere to expand and cool — with additional drag on satellites. We are already picking up some of the latter.

    Actually, no. The “top of atmosphere” in the greenhouse sense is just a few km up, while satellites move at 200 km and up. The temperature, and thus scale height, of that part of the atmosphere is sensitively controlled by Solar activity: when there are lots of sunspots, there will also be features like faculae and flares that emit in the far UV and X-ray part of the spectrum. This is absorbed in the higher atmosphere, causing it to heat up and ionize (the ionosphere). After a Solar eruption this part of the atmosphere will bulge out, causing increased drag on low satellites which is immediately visible in the tracking data.

    Actually I had hoped that the Sun would have remained quiet for a longer time, to give the GOCE satellite a longer lifetime… no such luck, it seems :-(

    These processes are largely (but perhaps not entirely) decoupled from the greenhouse thingy. The amounts of energy involved are small by comparison due to the extreme rarefiedness of the air up there.

    [Response: Yes, the "Top of atmosphere" nomenclature just means we are referring to the radiation that escapes to space, or enters from space. The radiation itself escapes to space from a "radiating level" -- more precisely a spread of radiating levels different for each wavelength. The radiating levels are for the most part down were that atmosphere is still pretty dense, specifically the troposphere and stratosphere. The "radiating level" is the infrared equivalent of the photosphere of the Sun. The interior of the Sun may be many millions of degrees, but the Sun radiates in the visible spectrum (with a color temperature of around 6000K) because that's the temperature of the layer from which begins to become transparent enough for photons to escape from. --raypierre]

  47. 97
    Doug Bostrom says:

    gary thompson says: 14 January 2010 at 12:51 PM

    You have -got- to be kidding. “eastangliaemails.com?” There’s an actual web site all about sifting through dust? People are spending their days dredging through a bunch of years-old emails, hoping to tease out some kind of thrill?

    It beggars belief.

    I don’t suppose it’s any use suggesting you pause, step back, consider how you’ve reached this point, how you’ve been led to spend your time in Talmudic scholarship over a bunch of ancient email?

  48. 98
    John E. Pearson says:

    91: Geoff wrote: “I should imagine that the problem would be indeterminate if only one boundary condition were to be imposed. ”

    Isn’t there a super-idealized model somewhere that we can look so that we wouldn’t have to imagine anything?

  49. 99
    Hank Roberts says:

    Jim Bullis, you’re misreading the picture.
    > http://chriscolose.files.wordpress.com/2008/12/kiehl4.jpg?w=480&h=350
    > It shows zero heat going into the ocean.

    No, that’s not correct. Remember you do need to read the article along with the image to get the picture.

    The ocean and the land are both “surface” — not being transparent, the surface is absorbing incoming photons.

  50. 100
    Hank Roberts says:

    John, I should have said the first link under:
    Science Links
    AIP:Discovery of Glob. Warm.


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