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  1. “Look, guys and gals, this is a really, really talented crew. How could you not believe them when they say global warming is a real problem?”

    Does anyone seriously dispute this? I *think* what’s disputed is the degree to which we are confident that CO2/GHGs are the primary driver. And in that regard, “how could you not believe them when they say” that nature is potentially more complex than humans are ingenious. The oceans are a mystery. The GCMs are fallible, however wonderful their creators are.

    What’s with pushing the “belief” thing, anyways? Can we not just stick with the facts?

    Comment by Richard Sycamore — 13 Dec 2007 @ 6:47 AM

  2. Thank goodness someone is dealing with the important ptarmagan-feasting-on-willow issue!

    Actually here in Scotland we have a more serious potential problem with the ptarmigan. The ptarmigan population (like the mountain hare) is restricted to the relatively small areas of mountain regions that retain an “Arctic-like” environment (the Cairngorm plateau and the parts of the NW Highlands). Since Scotland is rather Northerly and is feeling the effects of global warming quite significantly (the rather rudimentary Scottish skiing “industry” is more or less dying on it’s feet (or skis)), there is considerable concern for the creatures like the ptarmigan who are starting to find conditions unfavourable. At the very least it looks like they may have to learn not to turn white in the winter…

    Comment by Chris — 13 Dec 2007 @ 7:38 AM

  3. A. S. McEwan gave the Shoemaker lecture today, on that topic.

    Was it all cobblers?

    Comment by stuart — 13 Dec 2007 @ 7:52 AM

  4. I am sending this comment, but I have never received an acknowledgement or reply to my prvious such messages.

    My questions are:

    Has there been any modelling to suggest what can be sustainable human energy use (and corresponding life-style)from the point of view of CO2 sink?

    How can we presume that a new equilibrium can be sustained in terms of average global temperature, when an equilibrium is just not possible with use of fossil fuels, as CO2 will just keep on increasing ad-infinitum in the absence of any expansion in the CO2 sink?

    I would look forward to receiving reply/comments on the above questions

    Best Regards

    Vinod Gupta
    New Delhi
    India

    Comment by Vinod Gupta — 13 Dec 2007 @ 8:01 AM

  5. Hi Vinod,
    I’m not a commentator, but I’ll take a stab at your question. First, the question of sustainability and energy use is not simple. I suspect that a lot depends on the source of the energy–that is, you’d probably get a very different answer if you depend on solar or wind than you would if you depend on coal. The type of development is also important: India has developed via an information economy, making possible some improvement in environmental concerns, but failing to provide employment for a vast underclass. China’s decision to emphasize manufacturing has provided large-scale employment, but led to an ever worsening environmental crisis.
    Equilibrium occurs when the radiation escaping Earth equals incoming energy from the Sun–we’ll eventually reach equilibrium. The question is whether the new equilibrium will be conducive to maintaining the agriculture and infrastructure neeeded to maintain a civilized world with 9-12 billion people in it.

    Richard Sycamore, by all means, let’s stick to facts, and the fact is that there is no way you can explain the current warming without a significant contribution from anthropogenic greenhouse gasses. That fact is not dependent on models, and it is robust with respect to the uncertainties we have about oceans, aerosols and clouds. If you accept that warming is occurring, the energy driving that warming must come from somewhere, and an increased greenhouse effect is the only explanation that reproduces the observed trends. Fact!

    Comment by Ray Ladbury — 13 Dec 2007 @ 8:54 AM

  6. I have gotten nowhere trying to change Scotland’s winter albedo shooting partridge on Boxing Day , but inspired by raypierre’s fete de Noel will try switching to ptarmigan.

    Since GG forcing seems to be rising by about 3 microwatts / m2 per day , a days bag of 100 ptarmigan should offset the daily climate forcing of about as many humans assuming the birds are hit cleanly causing 1 square meter of white feathers to land on the ground and remain reflective till next season.

    I realize it would be better to do this at a lower latitude, but equatorial Boxing Day shoots seldom feature ptarmigan

    Comment by Russell Seitz — 13 Dec 2007 @ 8:56 AM

  7. #4 Sustainable CO2 sinks
    Hi Vinod,
    I’ve yet to hear of a tested model for a sustainable CO2 sink. However I do know of a natural one: plants. They devour CO2 and grow with this absorption. The problem with plants is that they eventually get old and die, giving off methane. Solution: grow plants, collect them when they start giving off too much methane. Capture the methane, use it for fuel as methane has a higher greenhouse effect than CO2, grow more plants etc.

    We could also send up weather balloons which collect greenhouse gases in the atmosphere. There is a great deal of gas up there so send quite a few. How many? Enough to collect a half terra ton? The simple fact of this is that it seems unavoidable that we must repair the natural systems that keep our world in balance.

    Comment by Harold Ford — 13 Dec 2007 @ 9:33 AM

  8. for Richard Sycamore.

    Any candidate “primary drivers” for GW other than green house gases?

    Comment by Don — 13 Dec 2007 @ 9:49 AM

  9. Excellent post! This is what blogs were invented for… to give a direct look into real life. Besides giving a welcome glimpse of new research, it shows how climate science is actually done, which is a good way to educate everyone. It would be better still if you would take note of some of the ongoing disagreements, not make it seem as if everyone was marching, as the critics say, in lockstep.

    Comment by Spencer Weart — 13 Dec 2007 @ 10:03 AM

  10. Shrubification. I like that word.

    Is that one or two b’s?

    Comment by Thomas Lee Elifritz — 13 Dec 2007 @ 10:59 AM

  11. Re #1: [I *think* what’s disputed is the degree to which we are confident that CO2/GHGs are the primary driver.]

    I’m not a climate scientist, so I’ll welcome corrections from those who are, but I think you’ve got this exactly backwards. There is much more certainty of the fact the CO2 is the primary driver than there is of the exact amount of actual warming. The GHG effect is (comparatively) simple physics: measure the amount of CO2 and do the math. Coming up with a firm figure for warming requires integrating all sorts of measurements from around the world, each one having uncertainties & possible errors, and then taking into consideration all sorts of natural variation.

    Comment by James — 13 Dec 2007 @ 11:15 AM

  12. #5 Ray, The observed trends do not fit the models—FACT. You cannot simply say the models are consistent with the observations, for if they were, then you would see the troposphere warming at a higher rate than the surface, in fact the models indicate that the troposhere will heat at a rate 2-3 times more than what the observations show. Please explain this inconsistency.
    And, there are many ways to illustrate current warming trends without anthropogenic causes, one simply has to turn the knobs on the models to illustrate this. Just because one accepts that warming is occuring, which undoubtedly it is, this does not mean that one HAS to accept that humans are causing it, or that the current warming is unprecedented.
    Now, since the models are wrong, and the only way that they could be correct about CO2 driving temperature would be to observe the troposphere heating in ways that it is absolutely not, should we not try to look to where “the energy driving that warming” is really coming from?

    [Response: This has as much logic as someone in a fog bank declaring that because they can’t see where the road goes, it must curve right. Weather noise obscures climate; observational inaccuracies obscure climate; model imperfections obscure climate. Sometimes a signal is clear, but not in this case. Insisting that it is – even when there are models that even less tropospheric warming over this period than the obs is foolish. – gavin]

    Comment by Gaelan Clark — 13 Dec 2007 @ 11:37 AM

  13. Ray Ladbury states in post 5

    “If you accept that warming is occurring, the energy driving that warming must come from somewhere, and an increased greenhouse effect is the only explanation that reproduces the observed trends. Fact!”

    Fact? – Not quite! Surely the energy responsible for almost all warmth comes from the Sun and that it’s rather more likely that CO2 simply traps some of this energy as heat.

    [edit -OT]

    Comment by BrianMcL — 13 Dec 2007 @ 12:06 PM

  14. RE #1 & “What’s with pushing the “belief” thing, anyways? Can we not just stick with the facts?”

    Well, see, the situation is this: There are those who believe the facts, and there are those who don’t believe the facts.

    And you’re right about the models — they don’t EXACTLY replicate reality (that’s why they’re called models). And from what I’ve been reading they seem in general to be underestimating effects of global warming — like Arctic & Greenland ice & glacier melt. And I understand it’s hard to incorporate some of the slow positive feedbacks (melting permafrost, hydrates), which we can conceive of via scientific understanding of physics. In fact, it doesn’t even take a Ph.D. to understand that heat eventually tends to melt ice. However, it may be hard to quantify these processes and concomitant GHG releases with some equation. But that doesn’t mean they don’t exist and could make global warming a entirely more dangerous ball game than what we are able to quantify and model right now.

    As people living in the world, concerned about life, we need to be focused on the high end scientific projections and possibilities, and work to avoid them turning into facts.

    We can certainly hope for the best, but should be working to avoid the worst.

    Comment by Lynn Vincentnathan — 13 Dec 2007 @ 1:38 PM

  15. Gee Gaelan, the world is so simple when you don’t understand it, isn’t it? First, as Gavin has pointed out, you are looking for a signal in very noisy data. Second, some of the knobs on your little model have very little wiggle room, because they are constrained by multiple independent lines of evidence. Greenhouse forcine is among the most constrained parameters. Do yourself a favor and actually learn a little bit about global climate models. Start with the AIP history
    http://www.aip.org/history/climate/index.html
    and then read
    http://www.realclimate.org/index.php/archives/2007/04/learning-from-a-simple-model/
    I also recommend:
    http://www.realclimate.org/index.php/archives/2007/08/the-co2-problem-in-6-easy-steps/

    Y’all come back, hear?

    Comment by Ray Ladbury — 13 Dec 2007 @ 2:00 PM

  16. Re 13, Uh, Brian, that’s how the greenhouse effect works–absorbing outgoing IR.

    Comment by Ray Ladbury — 13 Dec 2007 @ 2:04 PM

  17. Thanks for posting! Yes, Rock Stars!

    Of course, I am sure I am not alone to hearing how the upcoming talks of Thu Aft and Fri AM with James Hansen, et al, are received. Rest up… :-)

    16:00h GC44A-01 Tipping Points,
    08:00h U51B-01 Climate Sensitivity

    Comment by Jim Redden — 13 Dec 2007 @ 2:04 PM

  18. Ray, Thank you for putting me into my place. I do deserve it.
    Have you had a chance to read the following? Please, do afford me your comments.

    “http://www.vulnerabilitynet.org/OPMS/view.php?site=seiproject&bn=seiproject_hotel&key=1140130266″

    Comment by Gaelan Clark — 13 Dec 2007 @ 2:46 PM

  19. Ray,

    You wrote: “Lonnie also pointed out, that with regard to tropical mountain glacier retreat in general, the rapid retreat supports the vertical amplification with height seen in GCM’s and in the moist adiabat, suggesting that evidence to the contrary from radiosondes may be more a data problem than a physics problem.”

    But what Lonnie said is a step too far. What the radiosondes are saying is that the warming is happening mainly close to the surface. Therefore, the melting of the glaciers at high altitude does not prove that the radiosondes are wrong because the mountain glacier melt is also at a surface. That evidence neither proves nor disproves whether the radiosonde data is right or the computer model theory is correct. The radiosonde data may be ugly, but to quote Thomas Huxley “That’s the ugly fact, which slays a beautiful hypothesis, the great tragedy of science.”

    Moreover, the melting of the Arctic sea ice is another surface melt. Since it is greater than that modeled fits with the radiosonde data. In other words the models are wrong, and the enhanced warming from carbon dioxide operates at the surface and not high in the troposphere!

    Karl Angstrom showed that Arrhenius’ greenhouse theory of ice ages based on radiation was wrong because the absorption is saturated in the CO2 band (667 microns). Later in 1927 G.C.Sipmpson, confirmed this by showing that the radiative balance is maintained by clouds altering the incoming shortwave radiation (ISR) rather than by the surface temperature altering the outgoing longwave radiation, which is also saturated.

    The greenhouse gas theory, originally proposed by Tyndall, works by carbon dioxide affecting the surface temperature and acts like a blanket preventing it freezing and formation of ice sheets. Carbon dioxide, by absorbing infrared radiation warms the air close to the surface. This prevents the surface losing heat by convection and so melts the marginal ice. The ice albedo effect provides a positive feedback.

    The greenhouse theory of Arrhenius is dead, long live the greenhouse theory of John Tyndall.

    Comment by Alastair McDonald — 13 Dec 2007 @ 3:47 PM

  20. Don writes:

    [[Any candidate “primary drivers” for GW other than green house gases?]]

    Several, mostly involving the sun, but none of them have worked out when examined closely.

    Comment by Barton Paul Levenson — 13 Dec 2007 @ 4:36 PM

  21. Alastair writes:

    [[Karl Angstrom showed that Arrhenius’ greenhouse theory of ice ages based on radiation was wrong because the absorption is saturated in the CO2 band (667 microns). Later in 1927 G.C.Sipmpson, confirmed this by showing that the radiative balance is maintained by clouds altering the incoming shortwave radiation (ISR) rather than by the surface temperature altering the outgoing longwave radiation, which is also saturated.]]

    CO2 absorption near the surface isn’t all that matters. A lot of it takes place in the upper atmosphere where the lines are NOT saturated. This was shown in the 1940s, and I think it was Gilbert Plass who finally put the saturation argument to bed in 1956. Even at low levels it doesn’t entirely work since CO2 has line wings way outside the saturated areas.

    [Response: Yes indeed. In fact Angstrom just did the experiments wrong. There is no saturation, and even if CO2 were saturated in the way Angstrom argued it wouldn’t prevent CO2 increases from warming the atmosphere. Search for the RC posts “A Saturated Gassy Argument” and “What Angstrom Didn’t Know” –raypierre]

    Comment by Barton Paul Levenson — 13 Dec 2007 @ 4:42 PM

  22. Alastair also writes:

    [[Carbon dioxide, by absorbing infrared radiation warms the air close to the surface. This prevents the surface losing heat by convection and so melts the marginal ice.]]

    Alastair, the surface does lose heat by convection. You can see it in desert mirages. Air is turbulent way up into the troposphere. And the measured lapse rates conform to what is expected from moist convection.

    Comment by Barton Paul Levenson — 13 Dec 2007 @ 4:44 PM

  23. I had to laugh at the thought of Raypierre writing this post at 2am, I imagine fairly tipsy. I wish I could write half as lucidly and with good humour when I am wide awake and sober. Well done :-)

    Comment by Chris McGrath — 13 Dec 2007 @ 7:10 PM

  24. Re #6: I’m concerned that the atmospheric release of carbon contained in the gunpowder may offset the increased albedo, particularly if Russell Seitz is a poor shot (which, I hasten to add, I am not asserting as fact). I wonder if he has modelled this adequately?

    Comment by S. Molnar — 13 Dec 2007 @ 8:27 PM

  25. #14 Lynne V:
    “Well, see, the situation is this: There are those who believe the facts, and there are those who don’t believe the facts.”

    Well, see, the situation is also this: there are those who believe the fiction, and there are those who don’t question what passes for “facts”.

    Models are fiction. And in this case the models happen to be failing in several small ways, which suggests their parameters may be slightly off. Perfectly reasonable proposition given the amount of uncertainty in the parameter estimates. Which parameters are off, and by how much? The question, see, is how much total error there is, as estimated in out-of-sample model tests. Because this error is being incorrectly attributed to forcing processes for which there is insufficient data to ensure an accurate parameterization.

    I’m not here to undermine the credibility of the models. I’m here to suggest there needs to be a better accounting for how error propagates through the inference chain, from the model itself to humans who reason about the model. This is how science works.

    Comment by Richard Sycamore — 13 Dec 2007 @ 8:30 PM

  26. I’m sure he’s using a crossbow or a boomerang.

    Comment by Hank Roberts — 13 Dec 2007 @ 9:27 PM

  27. Gaelan, I’m not sure what you are asking me to comment on. The reply you link to is >4 years old. A more recent work by the same authors was the subject of a recent commentary here on RC. Soon et al. and others try to appeal to uncertainties, but the thing is we know the effect of adding CO2 to the atmosphere. It is constrained by several independent lines of evidence. So, regardless of how many other causes are identified, you still have the fact that in order for climate scientists to be wrong about CO2, they have to be wrong about many, many other things as well. So, yes, you may have a cause involving geomagnetic/heliomagnetic/GCR variations. And yes, aerosols may not be well understood. That doesn’t change the fact that we do understand ghg physics and that we’ve constrained its contribution pretty well.

    Comment by Ray Ladbury — 13 Dec 2007 @ 9:51 PM

  28. Re #24: [… the atmospheric release of carbon contained in the gunpowder…]

    But classically the carbon in gunpowder is obtained from renewable sources instead of fossil fuels: charcoal in the case of black powder, cotton in the case of smokeless powder (guncotton). Thus it should not present a problem – though I wonder if there might be a market for certified organic gunpowder.

    Of course, if one really wanted his/her participation in this to be as low-carbon as possible, there’s always the atlatl.

    Comment by James — 13 Dec 2007 @ 10:54 PM

  29. 4 Vinod Gupta: We really can’t sink the CO2. We have to not make the CO2 in the first place. There are many things we can do, each of which makes a contribution, called a “wedge.” The number 1 wedge is: Replace all coal fired power plants with nuclear power plants worldwide. Coal fired power plants produce 34% of our CO2 output, the largest single wedge. Please read the book: “Environmentalists for Nuclear Energy”, by B. Comby
    English edition, 2001, 345 pp. (soft cover), 38 Euros
    TNR Editions, 266 avenue Daumesnil, 75012 Paris, France;
    ISBN 2-914190-02-6
    order from: http://www.comby.org/livres/livresen.htm
    Read a review of this book by the American Health Physics Society at:
    http://www.comby.org/media/articles/articles.in.english/HealthPhysics-NUC-July2002.htm

    Fossil fuels such as coal oil, and gas, massively pollute the Earth’s atmosphere (CO, CO2, SOX, NOX…), provoking acid rains and changing the global climate by increasing the greenhouse effect, while nuclear energy does not participate in these pollutions and presents well-founded environmental benefits.

    Renewable energies (solar, wind) not being able to deliver the amount of energy required by populations in developing and developed countries, nuclear energy is in fact the only clean and safe energy available to protect the planet during the XXI st century.

    This book answers essential questions about nuclear safety, the Chernobyl accident, the public health problems our society has to face, viable solutions for nuclear waste, the benefits of clean nuclear energy for the environment, and important information about the future of our planet.

    4 Vinod Gupta: Lifestyle is not the problem. Fossil fuel use is. We need to do research to find new ways to propel vehicles, but a combination of nuclear, wind, solar, geothermal and hydro electric power can provide sufficient energy. The problem is one of convenience to vehicles. Please everybody, read the review of this book by the American Health Physics Society and the book before making negative comments about nuclear power. The book will answer all of your questions and objections.

    http://www.ecolo.org
    Environmentalists For Nuclear Energy [EFN]

    Comment by Edward Greisch — 14 Dec 2007 @ 2:52 AM

  30. Re #29 [Edward Greisch] The IPCC does not agree with you with regard to the magical abilities of nuclear power to solve our problems. I quote from the WG III summary for policymakers:

    “Given costs relative to other supply options, nuclear power, which accounted for 16% of the electricity supply in 2005, can have an 18% share of the total electricity supply in 2030 at carbon prices up to 50 US$/tCO2-eq, but safety, weapons proliferation and waste remain as constraints.”

    On the whole, I put more trust in the IPCC’s WG III than in a bunch of nuclear enthusiasts. I notice that the review you cite begins “AT A TIME when most of the media and politicians seem to be brainwashed by antinuclear cults…”, which might suggest to some that the review itself comes from someone with a rather partisan stance.

    Moreover, there is no likelihood that China and India will turn from their abundant, cheap coal to import uranium, of which neither has much, on a large scale. Both are in fact expanding nuclear power, so they are clearly not fundamentally opposed to it, but at rates which hardly dent the rapid increase in their CO2 production – only CCS or economic collapse could do that.

    “Lifestyle is not the problem.” I look forward to your explanation of how nuclear power will enable the aviation industry to keep expanding at its planned rate without greatly increasing emissions over the next few decades, how nuclear power will make it possible to cut down Brazilian and south-east Asian rainforests for soya and palm oil without releasing vast quantities of CO2 and methane, etc.

    Comment by Nick Gotts — 14 Dec 2007 @ 5:41 AM

  31. Re #29 [Edward Greisch]

    Incidentally, Edward, I’d be intrigued to know whether you are following Comby’s advice to live exclusively on raw food (certainly saves on the emissions produced by cooking!), including insects.

    Comment by Nick Gotts — 14 Dec 2007 @ 7:15 AM

  32. Edward Greisch posts (typically):

    [[ nuclear energy does not participate in these pollutions and presents well-founded environmental benefits.]]

    Just look at the environmental benefits of Chernobyl, or Chelyabinsk, or Windscale, or Hansen…

    [[Renewable energies (solar, wind) not being able to deliver the amount of energy required by populations in developing and developed countries, nuclear energy is in fact the only clean and safe energy available to protect the planet during the XXI st century.]]

    Just plain false. Nuclear energy is constrained by the supply of uranium, solar energy is only constrained by the illumination at Earth’s surface — an average of 168 watts per square meter.

    Comment by Barton Paul Levenson — 14 Dec 2007 @ 8:00 AM

  33. Richard Sycamore #25, Wow, that’s about the most vague post I’ve seen lately. You tell us that models are “fiction” (Gee, I hope you can suspend disbelief when you got on board a plane or behind the wheel of a car.). Then we hear that the models are “failing in several small ways”. Of course you provide no specifics, as 1)that might actually require work on your part, and 2)you don’t understand the models well enough for specifics, anyway. Then you tell us that the “parameters” are off–do you even know anything about global climate models. Do you know how the “parameters” are determined? Do you know which “parameters” are well determined and which ones remain uncertain? Do you understand that some results from the models are quite robust regardless of the uncertainties in “parameters” like aerosols or clouds. Your discussion of error estimation and propagation is pure gobbledygook–even your vagueness can’t hide your ignorance here. Then you tell us, “That’s how science works.” Beautiful. So, Richard, ever do any actual science?

    Comment by Ray Ladbury — 14 Dec 2007 @ 8:11 AM

  34. I am not a scientist but I enjoy reading the posts. Given the “consensus” here that CO2 is the driver for global warming, it is interesting to see one post in favor of nuclear power, by an environmentalist no less, being so quickly put down. So, anyone care to suggest a resonable alternative to burning fossil fuel.

    As long as I am posting, is there an a concentration of CO2 above which additional radiative forcing is zero.

    Comment by Elery Fudge — 14 Dec 2007 @ 11:20 AM

  35. #32
    Ray Ladbury

    I didn’t realize vagueness is a crime. But if accusing me of ignorance based on two comments is your way of inviting dialogue, I would be happy to engage. Let me start by confriming my understanding your counter-argument. Are you asserting:

    (a) models are not hypothetical descriptions of reality
    (b) GCM/EBM parameters are known with certainty
    (c) error does not propagate
    (d) the models are not failing in several small ways
    (e) all of the above

    If you can outline your views on these points, I would be happy to show you that you don’t know everything. No apology necessary at this point. It can wait til later.

    Cheerio

    [Response: If you want to discuss issues, then do so, but setting up obvious strawman arguments to bat around is silly – this is directed at both of you. – gavin]

    Comment by Richard Sycamore — 14 Dec 2007 @ 11:20 AM

  36. Re #33 Elery Fudge “So, anyone care to suggest a resonable alternative to burning fossil fuel.”

    Largest rapid gains are available from energy efficiency and behavioural change – for example, insulating houses better and adjusting your clothing to the ambient temperature, flying and driving less, buying and running fewer power-hungry appliances (e.g. plasma TVs), eating less meat and dairy produce. In the slightly longer term, solar, wind, wave, tidal and geothermal power, depending on local conditions. Difficult and far from ideal, but essential because China and India are not going to stop burning coal any time soon, is the deployment of carbon capture and storage technology at fossil fuel power plants.

    “As long as I am posting, is there an a concentration of CO2 above which additional radiative forcing is zero.”

    No. It increases in proportion to the logarithm of CO2 concentration.

    Comment by Nick Gotts — 14 Dec 2007 @ 12:00 PM

  37. Richard, perhaps I misconstrued your posts, but they seemed to imply that GCM were not up to snuff scientifically–and did so with no concrete objections that could actually be addressed. Since this is an ignorant attitude. If you would care to raise concrete objections, they can be addressed. Otherwise, why would we have any basis to assume you know what you are talking about.
    To your straw men:
    a)Models are indeed descriptions of reality–I’m not sure why you felt a need to insert the superfluous adjective “hypothetical”. I might suggest you follow Mark Twain’s dictum: “If you see an adjective, kill it.” Models are useful in elucidating the important contributors in a physical system. You seem to have listened to only half of what George Box said: “All models are wrong…” and ignored the other part: “Some models are useful.”
    b)If you actually read my post, you would see that I I actually dealt with uncertainties. I said some contributors are nailed down tight, while some remain uncertain. Uncertainty in a model does not (or in a theory) does not prevent one from drawing very robust conclusions that persist despite that uncertainty. When you have multiple independent lines of evidence all pointing to roughly the same range of magnitudes for CO2 forcing, you can be pretty sure that aspect of the model is right, regardles of other uncertainties that persist.
    c)Of course errors propagate. You seem to imply that this is not investigated. It is, and that is why there is a range of values given in the IPCC reports. Again, if you have specific issues, we can discuss them, but error analysis is done for all the models.
    d)Actually the models are remarkably successful. They predicted >20 years of warming. They nailed the effects of Mt Pinatubo. If anything they have been too conservative wrt ice melt.

    Again, if you want to discuss specifics, that’s fine. To date, you’ve given no indication that any of your criticisms are based on actually knowledge of climate science, physics, modeling or the scientific method in general.

    Comment by Ray Ladbury — 14 Dec 2007 @ 12:13 PM

  38. Re #31: [Just look at the environmental benefits of Chernobyl, or Chelyabinsk, or Windscale, or Hansen…]

    I’d be interested in seeing facts as to environmental conditions at the last three of those. Chernobyl, from the reports I’ve seen, produced a net benefit to the surrounding environment.

    Too often this seems to be based on a circular argument: that radiation is bad for the environment is assumed, an increase in radiation is measured, therefore the environmental quality has degraded. It would be good if there were objective measurements, such as number & density of species.

    Comment by James — 14 Dec 2007 @ 12:59 PM

  39. The accusation of setting up a “straw man” is understandable, but incorrect. In a scientific dialogue it is necessary to establish clear positions. But when the participants don’t know each other there is often a reluctance to be the first to strike, as an offensive strike can expose you to a counter-strike.

    If there is no editorial tolerance for open discussion, then fine; I will leave. If there is, then let us continue. My question has to do with the supposed “pipe” that the supposed additional warming is in. I want to understand the process by which the heat got in the pipe, and how the pipe itself warms. But I would prefer to anchor the discussion in reality, as opposed to the analogies we’re becoming accustomed to hearing.

    No more accusations of “straw men” please.

    Comment by Richard Sycamore — 14 Dec 2007 @ 1:20 PM

  40. Re #36 (James) “Chernobyl, from the reports I’ve seen, produced a net benefit to the surrounding environment.”

    James, it should surely be obvious that Chernobyl is a “wildlife haven” because there are no people there. This point has been raised before – are you really unable to grasp it?

    “It would be good if there were objective measurements, such as number & density of species.”

    There has been some. See for example:

    A.P. Møller, T.A. Mousseau (2007)
    “Birds prefer to breed in sites with low radioactivity in Chernobyl”
    Proceedings of the Royal Society B 274, 1443-1448
    DOI 10.1098/rspb.2007.0005

    and

    Møller, A.P., Hobson, K.A., Mousseau, T.A. & Peklo, A.M. 2006 Chernobyl as a population sink for barn swallows: tracking dispersal using stable isotope profiles. Ecol. Appl. 16, 1696–1705.

    (abstracts are freely available online)

    However, I don’t think you’ll like the answers!

    Comment by Nick Gotts — 14 Dec 2007 @ 1:31 PM

  41. Both strawman and distraction from climate discussion, there

    > Chernobyl, from the reports I’ve seen, produced a net benefit …
    > It would be good if there were objective measurements …

    There are. You need to look with Google Scholar, not Google.
    Cite your sources. Example, one of many:
    http://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-2656.2005.01009.x

    The area’s a roach motel for wildlife, animals move in and are more visible there, but reproduction isn’t working out well.

    Comment by Hank Roberts — 14 Dec 2007 @ 1:38 PM

  42. James posts:

    [[Chernobyl, from the reports I’ve seen, produced a net benefit to the surrounding environment.]]

    Also, the city of New York really is going to go public on some of its infrastructure. Let me know how many shares in the Brooklyn Bridge you want to buy.

    Comment by Barton Paul Levenson — 14 Dec 2007 @ 2:31 PM

  43. Re #38: [ it should surely be obvious that Chernobyl is a “wildlife haven” because there are no people there. This point has been raised before – are you really unable to grasp it?]

    Unable to grasp what I’ve been saying all along: the effects of a “worse than worst case” nuclear accident, whatever they may be, are evidently less detrimental to life than normal human activity? Remember that before the accident was hardly even a major metropolitan area, let alone something like a coal strip mine or tailings dump.

    Comment by James — 14 Dec 2007 @ 5:02 PM

  44. Re #39: [You need to look with Google Scholar, not Google.]

    The problem (in addition to the fact that I find it almost impossible to construct a Google search query which yields more relevant results than trash) is that almost everything Google Scholar finds is an abstract on some journal publisher’s web site, where I’d need to pay to download the full articles.

    Comment by James — 14 Dec 2007 @ 5:19 PM

  45. James, you said “from the reports I’ve seen” you formed your belief. Where did you see these reports? Who are you relying on for the misinformation?

    Okay, I agree with you about having to work at searching Google!

    I pasted your direct quote into Google with a question mark to invoke their natural language text search, exactly like this:

    “Chernobyl, from the reports I’ve seen, produced a net benefit to the surrounding environment”

    And you’re right, you get a load of crap, right at the top:

    The first two hits are Michael Crichton’s personal site. Bunk.
    Then bunk from a UK newspaper and an Australian TV station.
    Then bunk from SEPP.org

    So — the answer is to focus at least slightly instead of make the widest possible generalization.

    Seriously, a good reference librarian at any public library can help you learn how to do this. Since you say that’s the problem you’re having, you know you need to learn how to focus your queries.

    And the same reference librarian can help you enormously in how to read the abstracts you find with Scholar. Many of the links do actually lead to articles, or reference lists containing available text. With some help from a good librarian you can learn how to take the relevant strings out of the paywalled abstracts, and put those into further searches.

    Almost anything available lately for pay through Scholar will be available for free with some carefully crafted searching elsewhere.

    If you want help, though, how about asking for it rather than just posting what you believe and awaiting correction? It’d be kinder to you and to the rest of us. Just ask. We all get help here all the time. I’m just an amateur, but I’ve been reading for 55 years now and working hard at getting information the whole time.

    You can do it.

    But don’t blow off help — did you look at the one abstract I did provide? It surely gives you a start informing yourself.

    ——excerpt from abstract—-
    Barn swallows, compared to control area:
    ….The fraction of nonreproducing adults was on average 23% in Chernobyl compared with close to zero in Kanev and other European populations.
    3. … laying date did not differ significantly between the two regions, clutch was reduced by 7%, brood size by 14% and hatching success by 5% in the Chernobyl region relative to the control area.
    4. Annual adult survival, estimated from mark–recapture analyses, was on average 28% in the Chernobyl region, but 40% in Kanev.
    5. The relationships [measured] were generally confirmed [related to] ambient radiation levels in different colonies.
    6. The overall findings are consistent with the hypothesis that radioactive contamination in the Chernobyl region has significant negative impact on rates of reproduction and survival of the barn swallow.
    ——-end excerpt from abstract—–

    Thus my comment, this ‘roach motel’ result shows up in a lot of studies. You can find them. There’s lots of fascinating science coming out of this.

    None I’ve seen — NONE — supports what you believed. So I suspect your source fooled you and you fell for it. Lies are free. People will push them at you, to support their PR or political beliefs.

    But if you think education is expensive, try ignorance, as the bumper sticker says.

    You can learn to educate yourself. Learn to be skeptical.
    Learn to ask good questions from people like reference librarians.
    Learn.

    Comment by Hank Roberts — 14 Dec 2007 @ 5:56 PM

  46. James writes:

    [[The problem (in addition to the fact that I find it almost impossible to construct a Google search query which yields more relevant results than trash) is that almost everything Google Scholar finds is an abstract on some journal publisher’s web site, where I’d need to pay to download the full articles.]]

    Sad but true. It used to be that science journals were freely available in science libraries, but now most of them take only the “electronic version,” and you have to have a student password, at the least, to get in. I haven’t read a copy of Icarus in at least two years.

    Science is more and more being restricted to professional scientists, which, in my opinion, is not a smart thing to do. Science is not magic and should not be restricted to a small professional elite.

    Comment by Barton Paul Levenson — 15 Dec 2007 @ 7:24 AM

  47. #33 Elery Fudge:

    … So, anyone care to suggest a resonable alternative to burning fossil fuel.

    Hmmm… energy saving? (lots of low hanging fruit there) Solar thermal energy in desert areas, with thermal storage and long distance transport to consumer areas? Ocean thermal energy conversion (same transport challenge)? Equipping fossil fuel plants with capturing and underground storage (after all, that’s where the stuff came from)? Nuclear fusion (hard, but suitable for baseload, not retargetable for weapons, unlimited fuel supply)? Space solar energy (hard…)? …

    Some of these are available now, others require technology development. They will all lead to more expensive energy than what we have today, but affordable solutions exist. See the IPCC AR4 WG3 report (sorry for not giving links, typing this on a PDA)

    As long as I am posting, is there an a concentration of CO2 above which additional radiative forcing is zero.

    Interesting question… and the umpteenth time I come across it. Somebody is working hard to plant this meme. The answer is no: the forcing by a greenhouse gas, and the equilibrium temperature increase caused by it, is a logarithmic function of concentration. Like:

    Dt = k log(c/c0),

    where k is a constant, c0 the pre-industrial (or reference) concentration, and c current concentration. So every doubling produces the same increase in temperature. This relationship is remarkably robust, kmown to Arrhenius and reproduced by the physics in current models.

    Comment by Martin Vermeer — 15 Dec 2007 @ 10:07 AM

  48. My question has to do with the supposed “pipe” that the supposed additional warming is in. I want to understand the process by which the heat got in the pipe, and how the pipe itself warms.

    Then start reading, rather than expect people to take the time to educate you.

    This stuff ain’t stamped “TOP SECRET” and hidden in the bowels of the NSA or nuthin’, you know?

    The accusation of setting up a “straw man” is understandable, but incorrect. In a scientific dialogue it is necessary to establish clear positions.

    And you’ve established your position. To put it kindly, you should be working on filling in gaps of your knowledge, rather than saying things like

    If there is no editorial tolerance for open discussion, then fine; I will leave. If there is, then let us continue.

    Which implies you want to continue trumpeting your beliefs, even if your knowledge of the subject doesn’t even extend to the above-mentioned basic piece of knowledge.

    if accusing me of ignorance based on two comments is your way of inviting dialogue, I would be happy to engage.

    Apparently the accusation of ignorance is correct, right? Why should anyone want to engage in debate with you when you don’t understand basics?

    Models are fiction.

    Well, that’s a convincing argument!

    Comment by dhogaza — 15 Dec 2007 @ 10:39 AM

  49. Wossname declaimed ignorance and demanded education
    >”supposed pipe”
    It helps to use the correct search term.
    This will tell you what you want to know about that:

    Geophysics — Contributions of past and present human generations to committed warming caused by carbon dioxide.

    http://www.pnas.org/cgi/reprint/102/31/10832.pdf (full text)

    http://www.pnas.org/cgi/content/abstract/0504755102v1 (abstract)

    Wossname also declaimed
    > models are fiction
    Ray Bradbury, noted fiction writer, wrote:
    “People ask me to predict the future, when all I want to do is prevent it.”

    You’re not being taken personally here, I don’t even recall who posted this unoriginal stuff, I’m just doing the recreational typing, long form of the answer “use the Start Here button at the top of the page to check your assumptions”

    Another Ray Bradbury quote for you:
    “I’m working to prevent a future where there’s no education. The system we have has gone to hell ….”

    Comment by Hank Roberts — 15 Dec 2007 @ 11:02 AM

  50. Richard, OK, a question–something concrete. The “pipeline” analogy is not exactly accurate, but basically, once you start perturbing the system, some of the system’s responses are delayed and contribute to subsequent warming. First, you have to look at the way the greenhouse effect works. Greenhouse gasses absorb the outgoing IR at low to mid altitudes, so in their absorption bands Earth effectively radiates at a higher altitude/lower temperature. The equilibrium doesn’t get restored until the atmosphere warms enough that outgoing IR balances incoming radiation again–that takes time. Second, in response to warming, environments change, ice melts, some vegetation dies to be replaced by different species, and this changes albedo in the long term. Anyway, those are some feedbacks that lead to greater warming down the pipe.

    Comment by Ray Ladbury — 15 Dec 2007 @ 11:48 AM

  51. Re #29 [Edward Greisch]

    For some reason, this post has failed to appear despite being sent several times. One more try…

    The IPCC do not agree with you that nuclear power is the silver bullet. I quote from the “Summary for Policymakers” of the report of WG III:

    “Given costs relative to other supply options, nuclear power, which accounted for 16% of the electricity supply in 2005, can have an 18% share of the total electricity supply in 2030 at carbon prices up to 50 US$/tCO2-eq, but safety, weapons proliferation and waste remain as constraints.”
    On the whole, I trust the IPCC more than a group of nuclear enthusiasts.

    Moreover, there seems scant chance that China And India will abandon use of their abundant cheap coal to buy uranium on a large scale from abroad. Both are expanding their nuclear power programmes (so they are clearly not opposed in principle), but at a rate which hardly makes a dent in their rapid increase in CO2 emissions; only CCS or economic collapse are likely to do that.

    I note that the review of Comby’s book you cite begins: “AT A TIME when most of the media and politicians seem to be brainwashed by antinuclear cults…”. This might possibly indicate to some readers that the reviewer has a rather partisan approach to the issue.

    Comment by Nick Gotts — 16 Dec 2007 @ 9:11 AM

  52. Re $51: [The IPCC do not agree with you that nuclear power is the silver bullet.]

    Maybe because there ARE no silver bullets; no one solution that magically makes the problem go away. We need to be open to using anything and everything that might help, and even then the outlook is not encouraging.

    [Moreover, there seems scant chance that China And India will abandon use of their abundant cheap coal…]

    But we could say as much for any CO2-producing technology and country, adjusting the verbiage as appropriate: it’s unlikely that Americans will give up cheap electricity and SUVs, it’s unlikely that Brazilians and Indonesians will stop burning down the rain forest; it’s unlikely that North Africans will stop grazing their flocks on marginal grasslands…

    Regardless of what China & India do, if the US or other countries replace coal-fired generation with nuclear, solar, wind or whatever, that reduces the world’s CO2 output. We’ve wasted too much time waiting for the other guys to agree to go first. We need to start, then apply whatever pressure we can to get the rest to follow.

    Comment by James — 17 Dec 2007 @ 12:16 PM

  53. Re #52 (James) “Re #51 [Moreover, there seems scant chance that China And India will abandon use of their abundant cheap coal…]

    But we could say as much for any CO2-producing technology and country, adjusting the verbiage as appropriate:”

    I notice you carefully omit the alternative implicitly proposed: CCS.

    “Regardless of what China & India do, if the US or other countries replace coal-fired generation with nuclear, solar, wind or whatever, that reduces the world’s CO2 output. We’ve wasted too much time waiting for the other guys to agree to go first. We need to start, then apply whatever pressure we can to get the rest to follow.”

    I have no quarrel with that, nor with the point that we need to be open to using anything that might help – but it does not follow, as you seem to think, that we should necessarily use everything that might help: we need to think about what can be done fastest and cheapest (because resources of capital, labour and expertise are limited, and different approaches require different infrastructure), and with fewest undesirable side-effects. As I’ve noted before, to take an extreme case, developing and releasing a pathogen that would kill most of the world’s population might be a very effective counter to AGW, but I (and I am sure, you) would find it unacceptable. As you will be aware if you recall my previous posts, my position is that nuclear power is best avoided if and where possible, primarily because of the ineradicable links between nuclear power and nuclear weapons (I note that the Bush administration is opposed to Russia supplying uranium to Iran because of the risk the Bushehr reactor could be used to produce weapons-grade plutonium) – but that it is not going to disappear in the short term (France and Japan, for example, have invested so much money and prestige in it they are unlikely to change course).

    Comment by Nick Gotts — 17 Dec 2007 @ 1:21 PM

  54. Re #53: [I notice you carefully omit the alternative implicitly proposed: CCS.]

    Sure, for the same reason I omitted to suggest that everybody race out and start building fusion power plants: because we don’t know how to make it work in practice. Can the capture be done economically? Will the Chinese and Indians, or even the Americans, be willing to do it if it significantly increases the cost of electricity? Will the stored CO2 stay stored for the next few million years, or will it come bubbling back out in a hundred or so?

    Comment by James — 17 Dec 2007 @ 9:51 PM

  55. Re #54 (James) “Sure, for the same reason I omitted to suggest that everybody race out and start building fusion power plants”

    James, the comparison is ridiculous, as I’m sure you know. Read the IPCC WG III special report on carbon capture and storage, or at least the summary for policymakers.

    Here is what the latter says about costs (EOR is enhanced oil recovery):

    “Application of CCS to electricity production, under 2002
    conditions, is estimated to increase electricity generation
    costs by about 0.01–0.05 US dollars16 per kilowatt
    hour (US$/kWh), depending on the fuel, the specific
    technology, the location and the national circumstances.
    Inclusion of the benefits of EOR would reduce additional
    electricity production costs due to CCS by around 0.01–
    0.02 US$/kWh (see Table SPM.3 for absolute electricity
    production costs and Table SPM.4 for costs in US$/tCO2
    avoided). Increases in market prices of fuels used for
    power generation would generally tend to increase the
    cost of CCS. The quantitative impact of oil price on CCS is
    uncertain. However, revenue from EOR would generally
    be higher with higher oil prices. While applying CCS to
    biomass-based power production at the current small
    scale would add substantially to the electricity costs, cofiring
    of biomass in a larger coal-fired power plant with
    CCS would be more cost-effective.”

    China and India are much more likely to be willing to pay that amount extra than to leave all that coal in the ground and make themselves heavily dependent on uranium from abroad.

    Given the absurdity of some of the claims made (e.g. for the “net environmental benefit” of Chernobyl), I have the impression that you and a few other posters have a strong emotional attachment to nuclear power, just as many of its opponents have a strong antipathy to it. In general terms, either attachment or antipathy can lead to distorted thinking.

    Comment by Nick Gotts — 18 Dec 2007 @ 5:53 AM

  56. Re #55: […the comparison is ridiculous, as I’m sure you know.]

    No, I don’t know that at all. We have two theoretically possible but totally unproven in practice technologies. I’ll grant you that I’m not an expert on the subject, but practical CCS seems far more difficult to accomplish than fusion. How in the world would you even separate the CO2 from the exhaust stream? Chemical reactions? What reversible reaction, and what are the energy losses? Cooling it until it solidifies, or under enough pressure to liquify it? That takes lots of energy. Maybe selectively permeable membranes? Then you have the costs of transport and compressing for storage, and still absolutely no guarantee that it’s going to stay in storage once it’s put there.

    But if you don’t like the fusion comparison, how about that other pie-in-the-sky scheme, the hydrogen economy? That might be a better comparison, since the technical problems are more alike.

    “I have the impression that you and a few other posters have a strong emotional attachment to nuclear power…”

    Your impression is wrong. I don’t have any particular attachment to nuclear power. My attachment’s to reducing CO2 levels before the world’s completely screwed up. Show me another technology that will do what nuclear will with fewer side effects, and I’ll be overjoyed. I do have a strong attachment to dealing from evidence rather than mythology, and most of the public opposition to nuclear power seems just that.

    I also have a very strong opposition to the effects of fossil fuel plants, and coal in particular. That’s not limited to the CO2: I’d a thousand times rather live in Chernobyl’s dead zone than in some of the coal mining areas I’ve passed through.

    Comment by James — 18 Dec 2007 @ 12:27 PM

  57. Re #56 “I’ll grant you that I’m not an expert on the subject, but practical CCS seems far more difficult to accomplish than fusion.”

    Don’t argue this with me, I’m not an expert either. Argue it with IPCC WG III.

    “I don’t have any particular attachment to nuclear power.”

    Frankly, I don’t believe you, because you so persistently ignore expert opinion without adequate reason.

    “Show me another technology that will do what nuclear will with fewer side effects, and I’ll be overjoyed”

    Again, argue the point with IPCC WG III, who assess nuclear’s potential contribution as minor.

    In the absence of some reasoned explanation of where you believe IPCC WG III have gone wrong on the two key points I have reiterated in this post, I will not respond further in this thread.

    Comment by Nick Gotts — 18 Dec 2007 @ 1:49 PM

  58. James (56) — You could (and should) first take the time to learn something about CCS before posting regarding it. It is neither terrribly difficult nor costly. Indeed, the initial studies appear to indicate that the sequestered carbon dioxide chemically binds to matter in deep saline formations, making the sequestration even more secure than had been earlier anticipated.

    Comment by David B. Benson — 18 Dec 2007 @ 2:28 PM

  59. > I’d a thousand times rather live in Chernobyl’s
    > dead zone than in some of the coal mining areas…

    As an individual, selfishly, I agree with you, at my age it wouldn’t make any great difference if I was careful where I put my fingers.

    But as a member of the species, this is a Darwin Award self-nomination, because fitness is measured in viable grandchildren.

    Comment by Hank Roberts — 18 Dec 2007 @ 2:42 PM

  60. Nick and James, It is easy to get caught up in an infinite loop on a subject as nuclear power. I think it suffices to say that no matter whether we rely on nuclear, renewables or both, we face a very difficult task when it comes to meeting future energy demand without increasing CO2 emissions. I think it is a mistake to prejudge the solution. We will have to weigh risks, costs and consequences as we go and take the course that seems most likely to yield success at the time we have to decide.

    Comment by Ray Ladbury — 18 Dec 2007 @ 2:45 PM

  61. Re #59: […fitness is measured in viable grandchildren.]

    I think fitness is better measured in genes which survive. So if for instance you produce a lot of viable grandchildren, just like everyone else, they exceed the food supply and wind up killing each other off, demonstrating that too many grandkids results in negative fitness. Or if you don’t have grandkids, but spend your time ensuring the survival of your close relatives’ grandkids, you’ve demonstrated fitness without personally reproducing.

    Comment by James — 19 Dec 2007 @ 2:26 AM

  62. James posts:

    [[I’d a thousand times rather live in Chernobyl’s dead zone than in some of the coal mining areas I’ve passed through.]]

    I almost said, “I’d rather you did, too,” but I restrained myself at the last minute.

    -Pittsburgh boy

    Comment by Barton Paul Levenson — 19 Dec 2007 @ 9:17 AM

  63. James and Hank, Re your discussion of fitness–and WAY OFF TOPIC
    Hank: […fitness is measured in viable grandchildren.]

    James: I think fitness is better measured in genes which survive.

    Actually, James comment is more general. On average, a grandchild will carry only ~1/4 of the genes of the grandparent, and if a grandparent produces a lot of viable offspring, the good genes from said grandparent tend to survive. The distinction is very important when it comes to so-called “altruistic” behavior in social insects and a few rare mammals such as naked mole rats. In such species, only the “queen” reproduces, with most females fulfilling altruistic functions such as gathering food, tending to young… How can this make sense? Well, it turns out that in such social species, there is a high degree of genetic relatedness. Thus, even though they do not reproduce, an altruistic nonbreeder would be more likely to project its genetics into the next generation as long as its altruistic behavior provided sufficient benefit to the next generation.

    Comment by Ray Ladbury — 19 Dec 2007 @ 1:13 PM

  64. Re #63 Can’t resist, even though way off topic. Actually, Ray (as you may well be aware), with regard to the Hymenoptera (ants, bees, wasps – but not termites), there’s an extra twist. They have a “haplo-diploid” genetic system: males have only one set of chromosomes, and indeed, one parent. The result is that a female is more closely related to her (full) sisters than to her daughters – but the queen often mates with multiple males, and stores the sperm for years. The queen and workers also “prefer” different sex ratios in the young, and it turns out that a hive/nest is in genetic terms a “workers’ republic” rather than a “monarchy” – the workers get their way because it is they who rear the young. There are many other species, including ours, where individuals often help raise their sibs, and hence display their inclusive fitness other than by reproducing. We also have to be careful with terms like “altruistic” – you’re right to use scare-quotes. Sometimes, biologists restrict the term’s meaning to actions which favour others’ genes, rather than others as individuals – but if you do that, an infertile person murdering their entire family to obtain their wealth turns out to be highly “altruistic” behaviour! My favourite quote on all this is from J.B.S. Haldane: “I will give my life for two brothers, or eight cousins.”

    Comment by Nick Gotts — 19 Dec 2007 @ 1:44 PM

  65. Nick–My lovely wife (an environmental scientist) has pointed out that the Haplo-dploidy in bees does indeed mean that the males only have half the genetic material of females, and that this proves that Monty Python was correct–Eric the half be was in fact half a bee.

    http://www.lyricsdepot.com/monty-python/eric-the-half-a-bee.html

    Comment by Ray Ladbury — 19 Dec 2007 @ 2:57 PM

  66. > J.B.S. Haldane: “I will give my life for two
    > brothers, or eight cousins.”

    Accurate math when cousins don’t marry; for honeybees and other highly related groups, the numbers differ.

    Comment by Hank Roberts — 19 Dec 2007 @ 4:16 PM

  67. #49/#50
    A furnace in the basement of a house turns on periodically. The house heats slowly to thermal equilibrium. There no correlation between furnace output and house air temperature. Does this mean there is no cause and effect?

    Surely you know where this goes. (You might think twice before labeling this a “straw man”.)

    Comment by Richard Sycamore — 19 Dec 2007 @ 8:49 PM

  68. Richard #67. Huh? Methinks you have an ill-posed problem. I don’t have the foggiest notion what you are driving at. Do you?

    Comment by Ray Ladbury — 19 Dec 2007 @ 8:58 PM

  69. Richard, the numbers may have changed because of delayed posts being released from the hyperactive spam filter (this has hit WordPress blogs a lot recently). So it’s really hard to guess what you’re replying to.

    If you’re arguing that Earth is heated from internal sources like Jupiter, I don’t think you’ve made a case.

    Comment by Hank Roberts — 19 Dec 2007 @ 9:15 PM

  70. Yes, Ray, I do. Do you recall this one?

    “Say it three times every night before going to sleep: Temperature goes up. Solar stuff goes up and down and up and down and up and down. You can no more make a trend out of that than you can make a silk purse out of a sow’s ear.”

    Tell me about “the pipe” in that context. We’ll see whose problem is ill-posed.

    [Response: I don’t see any contradiction here. What in the world are you trying to get at? In your furnace example, there is a phase lag between the periodic forcing and the periodic temperature response. The phase lag tells you about the thermal inertia of the house. That’s standard signal processing stuff, and in fact routine in the way the Earth’s response to the seasonal or solar cycle is analyzed. –raypierre]

    Comment by Richard Sycamore — 19 Dec 2007 @ 9:50 PM

  71. Yes, phase lag, raypierre. Now we’re getting somehwere. Please continue.

    Comment by Richard Sycamore — 19 Dec 2007 @ 10:33 PM

  72. Ok, I’ll help. What is the chance that the time scale of the varying periodic input is faster than the time scale of integration performed by the body with the thermal inertia? And what would be the consequence?

    [Response: Try again. There is no one single thermal inertia for the Earth.There are a vast range of time scales involved. The atmosphere has time scales of days to months, above the boundary layer. The ground itself has a continuous range of scales, because of the nature of heat diffusion. The mixed layer of the ocean has a time scale of a few years, the deep ocean maybe a few centuries to a thousand years. Glaciers can have surges that respond on a times scale of days, and accumulation times that can be in the millennia. Carbonate dissolution in the Ocean introduces time scales on the order of ten thousand years. Vegetation feedback is in between. Silicate weathering has the chance to buffer climate on time scales of a half million years or more. Take your pick. I don’t think you are making much progress on refining your question. –raypierre]

    Comment by Richard Sycamore — 19 Dec 2007 @ 11:31 PM

  73. Re #63, 64, and related genetics: Interesting, but I was thinking of a somewhat different situation, involving different strategies for maximizing reproductive fitness. At one extreme you have what might be called the codfish approach: produce millions of offspring in hopes that some will survive. At the other we have what mammals, and notably humans, do: have few offspring, but invest large amounts of energy in seeing that they (or those of other members of your pack/herd/tribe) survive.

    So, when faced with the prospect of limited food supply, it would seem that the optimum reproductive strategy would be to have still fewer offspring, giving those a better chance of survival, than to have more who are unlikely to survive the increased competition, which they’ve created simply by existing.

    [Response: hmm all very interesting, but aren’t we straying rather far afield from our topic? –raypierre]

    Comment by James — 20 Dec 2007 @ 12:08 AM

  74. Re: inline response in #72
    With a solar cycle varying on the decadal time scale and the mixed and deep ocean layers bracketing that – with integration times of a few years and a few centuries – does it make sense to you to assert that a pulsed input must lead to a pulsed output? Is it impossible that the input is buffered, to lead to a gradual rise in ouput? Maybe it is logical, I don’t know. I would simply like to hear your justification for the statement in ‘Les Chevaliers’ that inputs that go up and down and up and down can not lead to a rising trend in output. This view seems blissfully ignorant of “standard signal processing stuff” and maybe even some basic facts about the oceans. But enough. I come to hear the experts speak, not myself.

    Comment by Richard Sycamore — 20 Dec 2007 @ 8:56 AM

  75. Richard Sycamore, OK, I’ll bite. First, most of the drivers aren’t really periodic. Second, do you know of a physical system that responds to a periodic input with a monotonically increasing response? Can you even construct a differential equation that would behave in such a manner (without imaginary coefficients, I mean)?
    And unless you can find some really serious heretofore unknown feedbacks, Mr. Sun isn’t going to be able to drive the current warming.
    Look, Richard, do yourself a favor and actually learn something about the physics of climate and greenhouse gasses. You have access to everything you need on the front page of this site. Please ask questions, but I don’t think you are going to teach Gavin and Raypierre about the subject they have been studying for decades just yet.

    Comment by Ray Ladbury — 20 Dec 2007 @ 9:08 AM

  76. ERe # 75 Ray Ladbury: ” …do you know of a physical system that responds to a periodic input with a monotonically increasing response? ”

    Sorry for going off topic a bit: If I understand “monotonically increasing response” correctly, a classic example of a physical system showing this is muscle temporal summation:
    “Temporal summation is produced by stimulating the muscle rapidly enough so that one contraction is not finished before another begins. Thus, the effect of the second contraction is added to at least a part of the first contraction, and so on. If the muscle is stimulated rapidly enough, succeeding contractions may come so close together that no relaxation occurs between contractions. When this occurs, the smooth state of contraction known as tetany has been achieved. The frequency of stimulus necessary for tetanization varies depending on the particular muscle.” http://bioweb.wku.edu/faculty/Crawford/frogmusc.htm

    An illustration of this can be found in Figure 8-7 of this online preview of this physiology textbook: http://books.google.com/books?id=cj9S_10muCYC&pg=PA123&lpg=PA123&dq=muscle+temporal+summation&source=web&ots=rw0TRVBR0y&sig=piLRXnqJuXxDxUH171ckqHtJAM4

    If I am mistaken about this, please feel free to correct me.

    Comment by Chuck Booth — 20 Dec 2007 @ 10:10 AM

  77. Re #74 (Richard Sycamore) “But enough. I come to hear the experts speak, not myself.”

    You could have fooled me!

    Comment by Nick Gotts — 20 Dec 2007 @ 10:11 AM

  78. Chuck, That is interesting, but I don’t think it would qualify as a monotonically increasing response–and I certainly don’t see how it would apply to climate, since the energy for contraction is not supplied by the stimulus, but rather by the ion pump in the muscle cells. The stimulus merely triggers release of the energy. Richard has proposed no source of energy other than insolation.

    Comment by Ray Ladbury — 20 Dec 2007 @ 10:28 AM

  79. #77 That you’re so easily fooled is not my problem. Good luck with that.

    #78 Ray, Hank, et al. perhaps my question is so ill-posed that it is unanswerable in its current form. I do not think so. Open-ended, perhaps. But ill-posed? Not likely. I’ll let you think about it and will check in periodically. Meanwhile, instead of attacking what I’ve said, why don’t you help me try to ask a better question? If you want to cite some literature, I will read it.

    Comment by Richard Sycamore — 20 Dec 2007 @ 6:57 PM

  80. Richard, the question sounds like you’re fishing for a particular answer. If you think it’s answerable, you might suggest how, and what kind of experiment you could do to prove your answer wrong.

    Comment by Hank Roberts — 20 Dec 2007 @ 8:45 PM

  81. #80 I am, Hank. And I thank you for your civility.

    If the time lag referred to by raypierre in ‘Flat Earth’ thread is short compared to the duration of the forcing, then GMST would be expected to closely follow the forcing, with little lag. [This is precisely the scenario that leads to “up and down and up and down and up and down” expectation for periodic solar forcing.] Alternatively, if the time lag is long, then the change in GMST would considerably lag the forcing and temperature would continue to change substantially before the climate system reached a new steady state.

    In particular for a situation in which climate is being forced by increasing solar activity, the increase in temperature beyond that realized at a given observation time that might be expected in response to forcing that has been applied until that time has been denoted “unrealized” or “committed” warming that is “in the pipeline” and is attributed to “thermal inertia”.

    We are told that mixed ocean layers have a response time of several years and deep ocean of several centuries. I want to understand as much as possible how that estimate of several years is derived, and why it is not, say, 20 years. I want to understand the factual basis behind raypierre’s assertion that periodic solar forcing must lead to a periodic response. To me, this is not inuitively obvious. Although it is clear why that might be the case of the time constant was short relative to the time scale of forcing.

    In short, I want to know if this up-and-down expectation is raypierre’s reasoned assessment, or just a quick one-liner made in rhetorical haste.

    [Response: You can read about the theory of linear mixed layer response in many places, including Chapter 8 of my book, a draft of which is available online. Follow the ClimateBook link at geosci.uchicago.edu/~rtp1. You can get a rough idea of the response time of the deep ocean by treating the ocean as a single mixed layer a few km deep, and such crude estimates are borne out by the response times in dynamic general circulation models. In a nonlinear system, of course you can get an aperiodic response from a periodic forcing but (a) even in such cases, the linearized system gives you a good idea of the damping of the signal due to thermal inertia and (b) you have to convince me what the strong nonlinearity is that could give such an effect in the face of the exceedingly weak amplitude of the solar cycle driving. –raypierre]

    Comment by Richard Sycamore — 21 Dec 2007 @ 12:05 AM

  82. #81 You sure have a way of making things more difficult and more complex than need be. We can restrict our attention to linear models for my purposes. I’m not invoking any strangely nonlinear behavior.

    I read your chapter, thank you. Many equations. Let’s use words. In your language, my question is what is your proof that the ocean does not have the thermal inertia required to attenuate the effects of the solar cycle? Context. In your chapter you show that the well-mixed layer of the ocean has a relaxation time of 1200d, and that this amount of thermal inertia is sufficient to attenuate, say, the annual seasonal temperature cycle. I am asking for the same calculation, but for the 11y solar cycle – the subject of your comment in ;Les Chevaliers’. [Yes, I could go get a PhD in climatology and do the calculation myself. I was hoping not to have to do that.]

    If such a simple question can not be answered, I give up. I would have thought it obvious from the start, when I first mentioned the furnace analogy. No one has told me yet why it is a poor analogue. Just mocking from the peanut gallery.

    Comment by Richard Sycamore — 21 Dec 2007 @ 6:01 AM

  83. Richard, Did you ever take a differential equations class? The nonlinearity Raypierre is talking would be reflected in your differential equation by a complex term (that is a term that involves SQRT(-1)). Where would you get such a term for any process that is significant in the energetics of climate. Moreover, the main period evident in solar activity is the 11 year cycle. That has been around as long as we have records going back–well back into geologic time. Why would you suddenly get a nonlinear term turning on now?
    Also, if you are looking for a delayed response, the delay has to be at least 50 years, since it’s been that long since we had insolation increasing. Where has all the energy been hiding all this time?
    Finally, I am curious why you find the greenhouse effect so incredible that you are willing to posit unknown physics in its place when it does a perfectly good job of explaining the current warming both qualitatively and quantitatively.

    Comment by Ray Ladbury — 21 Dec 2007 @ 8:36 AM

  84. Re #82 (Richard Sycamore) “We can restrict our attention to linear models for my purposes. I’m not invoking any strangely nonlinear behavior.”
    Then I would think (correct me if I am wrong, you mathematicians and physicists) there is absolutely no way a fluctuating input could cause a monotonically rising output.

    “I read your chapter, thank you. Many equations.”
    There’s a reason for that, Richard.

    Comment by Nick Gotts — 21 Dec 2007 @ 9:12 AM

  85. Richard: Let us simplify the problem. Assume for the sake of argument that from the year 1000 to 1900 the TSI has not changed, so that by 1900 we have an equilibrium situation (with some periodicity from the solar cycle, but no long term drift). Now increase the solar forcing from 1900 to 1950, after which it becomes constant again.

    We would expect to see that the increase in rate of temperature rise would reach a maximum in 1950. After that, there might be continuing temperature rise, but the rate would drop as the system started coming into a new equilibrium.

    Of course, this is not what we see: despite no rise in total solar output since 1950, we have seen the fastest rise post 1980. Now, you could argue some of that could be related to a drop in aerosols, but the timing just doesn’t work out well. And you’d still need to explain why the well understood radiation increase from GHGs wasn’t adding its own warming…

    Comment by Marcus — 21 Dec 2007 @ 10:29 AM

  86. Re 82- In order to demonstrate that a proposed explanation for an observed phenomenon is likely to be true, it is only necessary to show that the explanation is consistent with the known laws of physics and that it yields the observed results. It is not necessary to falsify all other possible proposed explanations (which, as we have seen, seem almost limitless!). If two explanations seem to meet this test, then there is an error somewhere that has to be thrashed out.

    Thus far, no one has come up with anything to explain the current warming that meets this test that does not include AGW as the primary component. Moreover, since the AGW explanation is so robust in terms of the physics, the observed data, and multiple lines of evidence, any proposed alternative explanation would have to show the error in the AGW analysis. And it would have to do so based, not on expert opinion, but on verifiable scientific analysis published in the peer-reviewed literature.

    So what you are getting from the busy scientists here is the real science. It is not realistic to expect them to spend time analysing speculative alternative explanations for global warming. You do it, publish it, and they will be glad to take a look at it.

    Comment by Ron Taylor — 21 Dec 2007 @ 10:48 AM

  87. Richard, I’m afraid the furnace analogy escapes me entirely. With the furnace, heating occurs when the furnace is on and stops when it turns off. Yes heat propagates throughout the house via convection, but there really is no delay. The other thing you need to appreciate is that attenuation of a cycle does not in any way lead to a monotonic increase, but rather a damped (or diminished) response. Again, if you understand differential equations, that’s the easiest way to look at it. In the absence of a driving force, you will have the natural behavior of the system (analogous to the homogeneous solution of the Diff. Eq.). Turn on a driver, and the response of the system will follow, more or less, the driver (that is, the inhomogeneous solution).

    For your solution to be operative, there would have to be some sort of heat reservoir that soaked up all that heat in the period 1900-1950 and has been hiding it from us ever since, and then, just by chance in about 1980, started doling out the heat at just the right rate to make it “look like” a greenhouse forcing. It would also have to be doling out more heat in Winter than Summer, and at night rather than during the day. And even then, you would have to explain why the known physics of greenhouse gasses suddenly decided to stop operating when we reached a CO2 level of about 300 ppm. Einstein once said that the most incomprehensible thing about the Universe was that it was comprehensible. Comprehend that and you’ll understand why science works.

    Comment by Ray Ladbury — 21 Dec 2007 @ 11:57 AM

  88. I see my last post has been disallowed. But the well-posed question is still not resolved.

    Ray, please stop trying to defend something that I am not questioning – greenhouse thory – and please answer the question that I am asking. raypierre says the time constant of the ocean mixed layer is 1200d. I want to know how that computation was made and why he is certain the number is not something larger, like 4800d. The size of this number would indeed influence the pattern of output (GMT) from a pulsed input (11y solar cycle). Nick Gotts in #84 asks to correct him if he is wrong. I am asking that you provide the proof if he is correct.

    Your #87 states that my analogy escapes you, but the second paragraph has the gist of it. The ocean is a large heat reservoir. It has heat buffering capacity.

    I will consider answering your question about GMT 1900-2007 AFTER my question is answered, not before.

    Comment by Richard Sycamore — 24 Dec 2007 @ 11:55 AM

  89. You realize you’re talking about a variation of about one in thirteen hundred, between solar max and solar minimum, right?

    Ray’s on holiday, as are all those with a life, leaving the thread open for the rest of us (grin). On second thought, I’ve got things to do myself from here on.

    Happy holidays, all.

    Comment by Hank Roberts — 24 Dec 2007 @ 1:42 PM

  90. You keep telling me not to ask the question, arguing that it’s not important. Rather than waste bandwidth doing that, why don’t you just answer the question? I’ll check back 28 Dec. Thanks.

    Comment by Richard Sycamore — 24 Dec 2007 @ 2:51 PM

  91. Richard, I believe some of the best measurements come from radioisotope studies after bomb tests. You can read about them in some detail here:

    http://www.aip.org/history/climate/oceans.htm#L_0488

    http://www.aip.org/history/climate/Revelle.htm.

    Moreover, I fail to see how a heat reservoir is going to bring you an accelerating warming trend. Moreover, given that the oceans are warming too, I would think this poses a bit of a problem for your hypothesis.

    Comment by Ray Ladbury — 24 Dec 2007 @ 2:54 PM

  92. Re #90

    Try the following as a good start:

    http://links.jstor.org/sici?sici=0012-9658%28198406%2965%3A3%3C970%3AMTEITG%3E2.0.CO%3B2-Y

    Modeling Terrestrial Ecosystems in the Global Carbon Cycle With Shifts in
    Carbon Storage Capacity by Land-Use Change
    William R. Emanuel; George G. Killough
    Ecology, Vol. 65, No. 3. (Jun., 1984), pp. 970-983.

    Comment by Phil. Felton — 24 Dec 2007 @ 4:05 PM

  93. Ray #91 You are attributing things to me that I never said, so I don’t quite follow. But I will listen. I don’t have a hypothesis, much as you would like to attribute one to me. I want to understand why Pierrehumbert said what he did about “up and down and up and down” solar cycle input vs. increasing trend in GMT ouput. He was suggesting that a causal relationship is not possible given a lack of pattern match. I want to understand the role of ocean heating and ocean mixing as a possible source of delay and of buffering of heat as a driver of GMT. If you don’t want to answer the question, fine, just say so. Ultimately it’s Pierrehumbert’s assessment that interests me, as it was him that made the statement.

    accelerating trend? I don’t remember saying anything about that. Why would I? [Never mind – that’s a distraction. Focus on the question.]

    Comment by Richard Sycamore — 24 Dec 2007 @ 4:19 PM

  94. Richard, Forgive my skepticism, but I would have thought that if you were really interested, you would have checked out the references I provided, which do pertain to your question of how we know ocean mixing times.

    You also have not answered the question: If the oceans are warming the rest of the world, why are they warming, too?

    And the accelerating trend I refer to is the current warming trend–warming due to a heat reservoir would tend to be most rapid right at first and then taper off. Consult your old differential equations text on why a periodic forcer cannot result in monotonically increasing response in a linear system. Merry Xmas, by the way. Ray

    Comment by Ray Ladbury — 24 Dec 2007 @ 5:08 PM

  95. I see I’ll be getting nothing but the runaround for Christmas. Ah, well, there’s always New Years.

    Ray #91, your link was inadequate. I already read Pierrehumbert’s excellent book, and it came close to almost giving an answer.
    Phil #92, your link was irrelevant.
    Ray #93, the oscillations get folded into the ocean’s convection. I fail to see how your freshman differential equations argument applies to a global mixer.

    Comment by Richard Sycamore — 24 Dec 2007 @ 6:55 PM

  96. Perhaps, Richard, you should work on refining what it is you want to know. The link I sent you describes how they determined timescales of ocean mixing–which is what you said you wanted.

    Changes in climate will be described by a differential equation, Richard. That differential equation will be either linear or nonlinear. You said you were satisfied with a linear equation. For that reason, you cannot get a monotonically increasing solution out of the differential equation with an oscillatory input. Perhaps you should review Freshman Diff. Eq.. Or perhaps you can provide a physical counter example…?

    Comment by Ray Ladbury — 24 Dec 2007 @ 9:44 PM

  97. Ray, what I want to know was worded very precisely in the comment that got censored, in between #87 and #88. So I will try again. (1) Please show me the calculation that was used to determine that the ocean heating time constant is 1200d. (2) Please explain how you know it is not something much larger, such as 2400d or 4800d. (3) Please explain why such a long time constant would not cause a periodic solar input to integrate to a virtually linear monotonic rise in GMT. (4) By all means, use differential equations if it helps your case. It will be interesting how you use them to represent ocean fluid dynamics. Whatever you do, just don’t wave your arms and tell me “calculus makes it so”. Show me the equations. I’m prepared to accept a rational argument. Just don’t give me rhetoric.

    If you’ve lost track of the context, please refer back to the original parapraph and graphic in Les Chevaliers. This is all about Pierrehumbert’s statement that “up and down and up and down and up and down” solar input can not possibly lead to a linear increase in temperature. As you know, I’ve given you a physical example already. If you are suggesting you’ve already proven it to be irrelevant, I would disagree.

    I’m afraid I can’t be much clearer than this. Thanks, anyways, for helping me try to figure out what it was raypierre was trying to say with that statement.

    Comment by Richard Sycamore — 24 Dec 2007 @ 11:34 PM

  98. Richard, if we have a periodic input (or in this case, a quasi-periodic input) to a system, the output will tend to follow it. If you put in a reservoir, the response of the system will be delayed, but still periodic (or quasi-periodic) with roughly the same perodicity as the input. The only way you get a growing output from a periodic input is if the input resonates precisely at the resonant frequency of the system. Since we are dealing with a quasi-periodic input, this does not apply. And even if it did, we would still expect oscillatory behavior–just oscillation with increasing amplitude from period to period. That’s not what we see.

    As to the oceans, the era of nuclear testing yielded a treasure trove of information–including the rates of flow, etc. of ocean currents. The C-14 spike from the nuke tests was a wonderful pulse source that elucidated a lot of the time dependence of the atmosphere and oceans. Read the reference from Spencer Weart’s page I provided (it is clear that you haven’t). And you still haven’t explained how the ocean can be warming the globe even as it is itself warming–violating the 1st law of thermo is a neat trick if you can do it.

    As to your “physical example”, I presume you are referring to the house with a furnace. First, in your example, the house will warm fastest when the furnace is on. If the thermostat is placed in the far corner away from the furnace, there will be a delay, but you will still see a pulse of warming that diminishes with time. This is nowhere near what we are seeing with the climate, where warming is accelerating with time.

    Look, Richard, all I can suggest is that you look into the history and science of the subject. It is clear you have not done so.

    Comment by Ray Ladbury — 25 Dec 2007 @ 9:29 AM

  99. And you have not proven your case, Ray. You merely repeat yourself. I understand well your POV. Enough. I want to see the equations. I’ve read your references and the answer to my question is not there. My guess is you can’t answer the question so you try to dodge it by sending me off on these tangents. It’s ok if you don’t have the means to make your case. I’ll just wait for raypierre.

    Comment by Richard Sycamore — 25 Dec 2007 @ 3:18 PM

  100. Re #95

    “Phil #92, your link was irrelevant.”

    I suggest you read it, I think you’ll find it’s more relevant than you appear to think.

    Comment by Phil. Felton — 25 Dec 2007 @ 4:25 PM

  101. To be clear, Richard, are you asking for help understanding the 1200-day number, from p. 237 of the textbook? There Ray writes:

    “… one can compute OLR(T) using a radiation model and some assumption linking the temperature and humidity profile to surface temperature, or one can use one of the linear or polynomial fits to the OLR curve discussed in Section 4. For example, with a linear fit to the OLR curve for a terrestrial atmosphere with 300ppmv CO2 and 50% relative humidity, b is about 2(W/m2)/K in the range 250K to 310K. The corresponding relaxation time [] is 1200 days for a 50 meter mixed layer, or 60 days for the 2.4m mixed layer which is equivalent to the thermal inertia of the Earth’s atmosphere. In consequence, the seasonal cycle is expected to be strongly attenuated on the ocean-covered parts of the Earth …”

    Comment by Hank Roberts — 25 Dec 2007 @ 4:54 PM

  102. Guys, I don’t think Mr. Sycamore is for real, in the sense that I don’t think he wants a real answer. He just intends to keep writing that we don’t have any answers or are evading his questions. Ray and others have answered his questions fully and he still insists he’s getting no answer. He’s a dishonest troll. Don’t even bother to answer him from now on.

    Comment by Barton Paul Levenson — 26 Dec 2007 @ 5:44 AM

  103. Richard, I believe that everybody here but you can see that what I’ve said is correct. A commentary in a blog does not lend itself to writing equations. Since you insist on simply repeating “no it isn’t” and refuse to address specifics, let’s go point by point.

    I have pointed out repeatedly that you cannot get a sustained increase from an oscillatory input unless the system itself is oscillatory and the input oscillates at the resonant frequency of the input. Do you dispute that?

    Comment by Ray Ladbury — 26 Dec 2007 @ 8:30 AM

  104. Barton, I’m starting to think the same thing. The dead giveaway is that fact that there’s no meaningful commentary on anything Hank, I, Raypierre or Phil have sent his way. I’m not even convinced that he would pass a Turing test.

    Comment by Ray Ladbury — 26 Dec 2007 @ 9:10 AM

  105. Perhaps the lines I quoted from Ch. 8 that (I think) are where Ray’s ‘1200 day’ number came from answered his question. Time will tell.

    Comment by Hank Roberts — 26 Dec 2007 @ 11:10 AM

  106. #101 I’m aware of the paragraph, Ray. Recall, I was the one who pointed you to it? Where are the error bars on those parameters?
    #102 I’ve had how many comments deleted now? Three? Four? And this makes it through?
    #104 Your piling on here serves what purpose? Makes you feel good I suppose.

    #103 I don’t dispute anything. Stop trying to stuff words in my mouth. I want to see a proof of that which you just asserted. You have not proven you are correct. You simply keep repeating your assertion that you are correct. Inculcation is not a logical proof. Give me your proof in word form if equations are too hard to post. Cite a paper. You wave your hands and say “the proof is in my first year calculus text”. That’s not a citation. That’s not an argument. That’s a dismissal. It’s a dodge. I don’t know of any text on differential equations that makes use of the world’s oceans as an example. Enlighten me.

    But talk about failing the Turing test. I think I will wait for raypierre’s return after the break. It is his remark; he should be willing and able to clarify what he meant by it. Please curb your temptation to reply. I doubt it can go anywhere productive as long as you can’t resist the urge to insult and to mob.

    [Response: Note, constructive engagement requires paying attention. Hank’s quote is very clear that the 1200d number comes from assuming a mixed-layer depth of 50m. It is not derived from data, though this is a reasonable guess for some purposes. In the real world, it’s clear that there isn’t a single time scale since many different processes play a part in the response (see here for instance). As to whether a linear differential equation with an oscillatory forcing function can have a linear increase through time, it can’t. The particular solution would have to have an oscillatory component (do a fourier transform for instance). In the simplest case, it’s obvious: the general solution of cdT/dt + T = Fcos(wt) is T=Aexp(-t/c) + Fcos(wt-b)/sqrt(1+(cw)^2), where tan(b)=cw. Please move the conversation to something more relevant. – gavin]

    Comment by Richard Sycamore — 26 Dec 2007 @ 11:31 AM

  107. Bye.

    Comment by Hank Roberts — 26 Dec 2007 @ 11:56 AM

  108. Richard, I said we are going through step by step. I asked point blank whether you dispute “that you cannot get a sustained increase from an oscillatory input unless the system itself is oscillatory and the input oscillates at the resonant frequency of the system.”

    As you replied “I don’t dispute anything.” I will take that as meaning that you accept the premise as stated (and corrected).

    Now, step 2: Do you dispute that solar forcing–especially on a decadal scale–is at most quasi-periodic?

    If you accept this, then by itself, it is sufficient to show that you will not get a steadily increasing response from climate due to an oscillating (not periodic) input.

    Couple to this the fact that there is no evidence for any type of resonant behavior in climate, and your argument is DOA.

    As to the mixing of the oceans, our understanding of rates of mixing/relaxation has been pretty much the same since Munk’s estimates using C-14 tracers. You can also use chemical tracers–SF6 for example. The point to understand is that it can and has been measured. Moreover, the rate of relaxation affects how sensitive the Southern Hemisphere is to the seasons vs. the Northern (due to differences in H20/land).

    BTW, you might be a little more convincing in your assertions that you have at least perused the references we provide if you at least go the names straight on who was posting which message #. (Hint: #101 was Hank, and he was just trying to figure out what your question was.)

    Comment by Ray Ladbury — 26 Dec 2007 @ 1:10 PM

  109. #106 inline reply by gavin. I’m fully aware of where the 1200d number comes from; I was the one who pointed it out. There is no uncertainty estimate on that number. Do you have one? gavin, you are surely not arguing that that one-liner is an appropriate model of the sun-ocean interaction. Have you actually followed the discussion?
    #107 bye. And thanks.
    #108 My question, one more time, is: where is raypierre’s proof of his assertion that a periodic solar input leads to a periodic temperature response. Do the long integration times involved in ocean fluid dynamics not change the nature of the response?

    If you guys are not able to advance the discussion any further, don’t blame me. I’m just asking a question. You are the ones avoiding answering it. Why, I have no idea. If you don’t have an answer, just say so.

    [Response: I gave you a relevant equation and there is no caveat that says that when ‘c’ gets large the nature of the response changes. That’s the thing with linear equations. If you want more realistic modelling you have to give up on the idea that there is a single timescale. Your insistence that a statement of consistency (50m => 1200d) is a derivation from data is just silly. But people have tried to estimate this from real world data and end up with timescales that vary enormously depending on what is being looked at – a couple of years to decades. Possibly you can now get to some point? – gavin]

    Comment by Richard Sycamore — 26 Dec 2007 @ 8:30 PM

  110. Re 109. Richard, the thing that annoys me as a lay participant here is your arrogance in blaming the scientists on this site for your inability to understand their quite straightforward responses to your questions. This paragraph in particular is plain offensive:

    “If you guys are not able to advance the discussion any further, don’t blame me. I’m just asking a question. You are the ones avoiding answering it. Why, I have no idea. If you don’t have an answer, just say so.”

    They have answered your questions. Please grow up and do a little homework, as they have suggested. Then come back with appropriately polite (and humble) questions. Otherwise, you give every appearance of simply trolling.

    Comment by Ron Taylor — 26 Dec 2007 @ 9:39 PM

  111. Richard Sycamore said: “If you guys are not able to advance the discussion any further, don’t blame me. I’m just asking a question.”

    No, what you are doing is asking a range of questions and then putting your fingers in your ears and saying “La-la-la-la, I can’t here you.” You have avoided reading the references we’ve provided. You have consistently taken an argumentative tone and rejected assistance as inadequate without providing specifics for why you felt it did not help. Richard, I suggest you go back and read over the exchanges. They do not do you credit.

    Comment by Ray Ladbury — 27 Dec 2007 @ 9:16 AM

  112. Ray, if you read for tone, as you do, I would be inclined to agree. My comments reveal that I am, exactly as I say, becoming exasperated with your hand-waving. But hopefully one reads for content, not just tone. Gavin Schmidt’s one-line description of the ocean in #106 is hardly satisfying, however “relevant” he claims it to be in #109. His further assertion that the 50m mixing depth etc. is not based on data is absurd. His insistence that there is no one time constant for ocean mixing is not only ironic given his one-liner, but adds unnecessary complexity to the analysis (something he does quite regularly for no apparent reason). I don’t dispute that any parameterizable problem can be split into any number of sub-problems. But this doesn’t change the question. My suggestion, as before, is to leave the subject alone for now, and maybe raypierre will address it in the new year. I’m sure he knows what he meant and can justify it with a proof. As for my tone, maybe he should have answered my question the first time around instead of deleting it.

    [Response: Your reading comprehension appears to leave something to be desired. You asked for an equation showing why oscillatory forcings must have an oscillatory component in the solution, I gave it to you. You asked for where 1200d came from, the answer is it comes from assuming a 50m mixed layer depth. I said that was a reasonable assumption (just look at any ocean atlas and do the averaging). You asked for the uncertainty on time constant, and you were told it depends on what you want to use it for but estimates range from months to decades – mainly because a one time constant model does not fit the real world. I fail to see any question that has not been answered. If you don’t like the answers, there’s not much I can do. – gavin]

    Comment by Richard Sycamore — 27 Dec 2007 @ 11:20 AM

  113. Sometimes reading several different books adds clarity. See also:
    http://ocw.mit.edu/OcwWeb/Earth–Atmospheric–and-Planetary-Sciences/12-301Fall-2006/LectureNotes/index.htm
    e.g.
    Part 5. Ocean and climate (7 lectures) taught by Prof. Carl Wunsch
    19-25 Ocean circulation for climate understanding (PDF – 1.7 MB)

    Comment by Hank Roberts — 27 Dec 2007 @ 11:24 AM

  114. Richard, When I look over your posts, the least charitable interpretation I can come up with is that you are a troll. The most charitable one I can come up with is that you do not have the educational background to pose the question you want to know in a way that makes sense to the scientists and engineers. There’s no shame in that. However, you gave the impression that you had some technical background. So perhaps we are answering what we think are the questions you are posing in terms that you do not understand. If you will tell us what your background is, it might help.

    Comment by Ray Ladbury — 27 Dec 2007 @ 12:34 PM

  115. Let me take a look at the house air question

    A furnace in the basement of a house turns on periodically. The house heats slowly to thermal equilibrium. There no correlation between furnace output and house air temperature. Does this mean there is no cause and effect?

    Let us assume simply that the fraction of time the furnace is on is a constant over some period, although it may not be strictly periodic.

    If we are in Hawaii, and the temperature outside the house is constant, the temperature inside the house follows the steady state solution for a damped aperiodic oscillator but the average temperature does not change.

    If we are in Boston and the duty cycle is short compared to the annual climate cycle or even the daily temperature cycle (day night), the temperature inside the house follows the steady state solution for a damped oscillator but the average temperature follows the temperature changes outside the house, with a positive offset. this is an excellent example of external forcing.

    So there are two effects, the steady state solution imposed by the furnace which imposes an equilibrium integrated over periods long compared to the average cycle time and the increase/decrease imposed by external (to the house) forcing of the temperature inside the house.

    If you doubt me, go play with your thermostat and monitor the internal and external temperature.

    WARNING: Your wife and kids will either leave or kill you.

    Comment by Eli Rabett — 27 Dec 2007 @ 12:58 PM

  116. Re # 112 Richard Sycamore: ” His [Gavin’s] further assertion that the 50m mixing depth etc. is not based on data is absurd.”

    What Gavin actually wrote was “the 1200d number comes from assuming a mixed-layer depth of 50m. It is not derived from data, though this is a reasonable guess for some purposes.”

    As I interpret his response, “It” refers to the ocean heating time constant of 1200 days, which is calculated assuming that the mixed layer extends to a depth 50 m. The depth of the mixed layer is based on hard data, but it varies with wind speed and other oceanographic factors – some textbooks put it at 100 m, others at 300 m. If you are wondering why a value of 50 m was used, why not ask that question directly?

    Comment by Chuck Booth — 27 Dec 2007 @ 2:03 PM

  117. #115 Thank you, Eli Rabett, for contemplating the example that I gave.

    Assume Boston. Assume winter. Assume the thermostat is located a little too near the furnace and that there is some distance between the ductwork and the coldest spot in the house furthest from the furnace. Assume the airfield between duct and cold spot is turbulent, i.e. weak teleconnection. Is it impossible that the temperature should rise almost lineraly despite the periodic activity and ouput of the furnace?

    Before going off on any tangents, recall this is about the sun-ocean interaction. If you don’t like my analogy, choose another to your liking. Better yet, argue in terms of the actual sun and ocean.

    #113 Thank you for the reference, Hank. I have already read some of Wunsch’s papers, but not these lecture notes. In fact, it is in part his work that leads me to question what raypierre meant when he insisted that solar goes up and down and up and down and global mean temperature rises linearly, implying that a driver and and a responder must correlate to one another. I have heard it argued that the thermal inertia of the oceans could be capable of buffering solar input and redistributing the heat in a time-delayed fashion. I want to know if that is a reasonable proposition.

    Assume I am a senior undergraduate. I won’t be insulted.

    Comment by Richard Sycamore — 27 Dec 2007 @ 3:54 PM

  118. Re: Richard Sycamore and his concern about the ocean mixed layer heating time constant:

    The following reference (easily obtained with a Google search) may have the information you are looking for:

    HEAT CAPACITY, TIME CONSTANT, AND SENSITIVITY OF EARTH’S CLIMATE SYSTEM
    Stephen E. Schwartz
    Accepted for publication inJournal of Geophysical Research
    [Revised 2007-06-14; minor corrections to 2007-09-17]

    [Response: Probably not. Try this instead: http://www.jamstec.go.jp/frsgc/research/d5/jdannan/comment_on_schwartz.pdf – gavin]

    http://72.14.205.104/search?q=cache:QxS_Xn7h_ekJ:www.ecd.bnl.gov/steve/pubs/HeatCapacity.pdf+ocean+mixed+layer+heating+constant&hl=en&ct=clnk&cd=7&gl=us&client=safari

    Comment by Chuck Booth — 27 Dec 2007 @ 5:03 PM

  119. Hank #113,

    Thanks for the link to the MIT lectures.

    Wunch’s chapter on ocean circulation finally put in perspective for me observations I made while serving as Navigator on ballistic missile submarines patrolling in the Norwegian Sea, North Atlantic and Mediterranean almost 40 years ago. We patrolled at 3 – 4 knots at depths generally between 50 and 150 meters. Our tracks were randomized over large chunks of the ocean. We would cover 6000 miles at these speeds during a patrol. Our inertial navigation systems continually logged and displayed the difference between inertial velocity (speed with respect to the ground) and the velocity derived from an electromagnetic log (speed with respect to the water). This difference is equivalent to the ocean current accurate to 0.1 knot. On some occasions we crossed the Gulf Stream enroute our patrol areas. This was spectacular; injection (sea water) temperature changes of 10F or more in a distance of a few hundred yards. Even more startling was the change in set and drift (ocean current)—0.5 knot to more than 6 knots over the same distance. These were dramatic but not unexpected. What was unexpected was the variation in ocean current spatially and temporarily in areas remote from the Gulf Stream and its eddies. Currents would vary up to plus/minus 2 knots over distances of a few miles. Returning to areas at a later time would show similar variations temporally.

    Wunch put this in perspective:

    “Kinetic energy of the ocean is 99.9% in the time-dependent rather than in the steady components.”

    We had a submarine saying “Happiness is to be at 400 feet in a state 6 sea”. I have experienced 15 -20 degree rolls at 400 feet during North Atlantic storms. 99.9 % indeed!

    Wunch summarizes our state of knowledge:

    “Describing the energetic of the ocean circulation remains an unfinished business.”

    “The reduction of the complex turbulent flow of the real ocean to a one-dimensional steady flow if useful would represent an astonishing breakthrough in the physics of turbulent fluids that would be landmark in the history of fluid dynamics. Purely verbal arguments about how the ocean circulation must change in the climate system should be regarded as science fiction.”

    Richard Sycamore seems to be seeking such a simple model to somehow link a solar insolation varying about an essentially constant mean with the increasing energy of the global system as measured by average surface temperatures.

    I don’t think Wunch’s statement should be taken to mean something might be hidden in that complexity that would invalidate the conservation of energy. I have no trouble following the arguments presented by Ray, Gavin and Eli showing that an increasing energy level can’t be induced by a driver varying about an essentially constant mean.

    Perhaps Richard could tell us exactly what Wunch wrote that:

    “leads me to question what raypierre meant when he insisted that solar goes up and down and up and down and global mean temperature rises linearly, implying that a driver and and a responder must correlate to one another.”

    And while he’s at it perhaps he could provide a reference for this:

    “I have heard it argued that the thermal inertia of the oceans could be capable of buffering solar input and redistributing the heat in a time-delayed fashion.”

    Why would the “redistribution” result in an increase of energy in the climate system?

    Comment by Paul Middents — 27 Dec 2007 @ 7:05 PM

  120. Paul, great story! I’d love to read more if you blog about submarining, somewhere sometime.

    Back on this thread — I went to look up the words Richard’s repeating, and so had 2 windows open, and mistakenly dropped a reply into the first of these two, where the misapprehension began near as I can tell.

    Richard, this reply’s for you:

    http://www.realclimate.org/index.php/archives/2007/12/les-chevaliers-de-l%e2%80%99ordre-de-la-terre-plate-part-ii-courtillots-geomagnetic-excursion/#comment-78006

    Comment by Hank Roberts — 27 Dec 2007 @ 9:36 PM

  121. #118 Thanks for the reference, Gavin. But this paper states that “contrary to the confident estimate in S07 of tau = 5 ± 1, a time scale as high as 30 or even greater is compatible with the S07 analysis of global years surface temperature”. I would think that the longer the time-scale of integration, the more *unlikely* the argument that GMT ought to fluctuate periodically in lockstep response to a periodic input such as 11-year solar radiation. i.e. At any given time, there’s more heat “in the pipe”.

    p.s. “autoregressive” is spelled incorrectly.

    #120 Following Hank’s lead, maybe it would be better to switch back to “Les Chevaliers”.

    Comment by Richard Sycamore — 27 Dec 2007 @ 10:40 PM

  122. Please don’t go to another topic. One is enough. My mistake, posting there where I went to find the ‘up and down/up’ quote as cited.

    Where did you get this?
    > the argument that GMT ought to fluctuate periodically
    > in lockstep response to a periodic input in lockstep

    I can’t find that anywhere. If you read it or heard it, where??

    What’s observed is a trend, over time, statistically.

    Over the time span charted, ‘solar goes up and down’ with a near zero trend. Temperature goes up, an increasing trend.

    That’s what he said about the chart.

    Comment by Hank Roberts — 27 Dec 2007 @ 11:19 PM

  123. #122 Hank, you’ve shown that you can’t or won’t answer the question, so why not drop it for now?

    I’d rather not have a parsing war. But – as if you didn’t know – I am referring to raypierre’s phrase: “Say it three times every night before going to sleep: Temperature goes up. Solar stuff goes up and down and up and down and up and down. You can no more make a trend out of that than you can make a silk purse out of a sow’s ear.” I promise I’ll follow his instructions religiously once I understand what it means.

    You didn’t like the furnace example, apparently. So try this. Suppose a starving man with 3% body fat suddenly comes into prosperity and starts eating 4 huge meals a day, such that his body fat percentage rises gradually to 15%. Periodic input, linearized output, through time-delayed metabolic integration.

    I’m obviously not an oceanographer so you tell me why this analogy doesn’t work. Any equations you want to use, by all means. Gavin has shown it is not that difficult. I only ask that you be sure they are applicable for the case of filtered solar radiation striking the ocean surface.

    (When you’re finished, let’s wrap up the silk purse for raypierre!)

    Comment by Richard Sycamore — 28 Dec 2007 @ 8:38 AM

  124. Richard,
    Um, actually you will not get a linear output. Weight will go up on eating and down on elimination. Conversion to body fat will depend on a variety of metabolic factors, but it too, will be periodic, albeit perhaps with a phase shift. Your impression of a linear response will be due to the infrequency of measurement.
    Moreover, while the intake of calories is periodic, the increased amplitude is a step function–and hence aperiodic.
    You seem to have a tendency to think your examples about half-way through–this is not characteristic of someone who has a lot of experience with quantitative reasoning.

    A large heat reservoir like the oceans can damp the response to a periodic input. It cannot take a periodic input and turn it into a monotonically increasing output.

    Richard, please think what you are asking us to consider:
    First, solar output has always fluctuated. The 11-year solar cycle has been known at least since the time of Galileo (longer, perhaps, if some Chinese historians are right). None of the fluctuations seen to date is sufficient to explain the dramatic rise in temperature. Yet you want us to believe that somehow, right about 1970, this periodic input starts to give rise to a monotonically increasing output.
    Gavin has given you the equations. They didn’t help you. We have given you references. They did not help you. We have shown you why your analogies are not applicable. You couldn’t see it. In fact, you’ve given no indication of even having considered what we have provided.

    Comment by Ray Ladbury — 28 Dec 2007 @ 9:46 AM

  125. Re #123 Richard Sycamore

    Surely, when RP says in ‘Les Chevaliers de l’Ordre de la Terre Plate, Part II':

    Temperature goes up. Solar stuff goes up and down and up and down and up and down. You can no more make a trend out of that than you can make a silk purse out of a sow’s ear.

    what he (and B&D) is referring to is solar output (TSI, or S(t)) is averaged over the cycle (~11, ~22 years or whatever) and, moreover, that since TSI is held to be roughly constant (over the cycles) these last ~50 years that it cannot be used to explain the observed temperature increase (i.e. it ain’t the sun causing the excursion; but temperature increase can be attributed to GHGs).

    I’ve missed where this has been conflated with oceanic time constants, so perhaps I have misunderstood where you are coming from in #123 and so will, too, indeed have to await RP’s return to put us all out of our misery.

    Comment by P. Lewis — 28 Dec 2007 @ 10:15 AM

  126. Yes, Ray posted this picture:
    http://www.realclimate.org/BD3.jpg
    It charts both solar and temperature.
    Draw the trend line through the solar — it’s about zero.
    It goes up and down, but stays around the same level over time.
    Draw the trend line through the temperature — it goes up over time.

    Ray described the lines on that particular chart.

    Happy New Year, Ray, wherever you are. Good example, I’m going to do the same thing. Happy New Year all.

    Comment by Hank Roberts — 28 Dec 2007 @ 11:04 AM

  127. #124
    1. Respectfully, you have still not proven your case. As before, you are merely repeating yourself.
    2. Gavin’s equation is overly simplistic for the case I described, and for the sun-ocean interaction.
    3. Your rebuttal of my example is not convincing. I agree that the ouput will oscillate given an oscillatory input, but the longer the time scale of integration, the more the amplitude of the output oscillation will be attenuated. (Is that even in Gavin’s equation?) Finally, if the integrator is noisy – which the ocean is – or if the circuit is driven by other agents then the amplitude of resultant oscillation may not exceed that of the noise.

    #125 If you’re miserable, don’t read.
    #126 ??? I am perfectly aware of the trend lines, Hank. Please, do not reply any further. You stopped listening long ago.

    Comment by Richard Sycamore — 28 Dec 2007 @ 11:55 PM

  128. Re #127

    “3. Your rebuttal of my example is not convincing. I agree that the ouput will oscillate given an oscillatory input, but the longer the time scale of integration, the more the amplitude of the output oscillation will be attenuated. (Is that even in Gavin’s equation?)”

    Yes it’s c which has the units of time.

    Comment by Phil. Felton — 29 Dec 2007 @ 1:05 AM

  129. Once again, people, I strongly urge you not to respond to Richard Sycamore at all. He’s here to start fights, not to learn. He will reject anything and everything you say no matter how many times you say it or how many ways you put it.

    Comment by Barton Paul Levenson — 29 Dec 2007 @ 7:19 AM

  130. Richard, in 117 you tried to rescue your house model by complicating it beyond recognition. You now introduce a thermostat, but what is the furnace doing? Is it still cycling randomly (your original model) or is it controlled by the thermostat? You are changing furnace controls in mid argument a sure sign that you recognize the errors in your original arguments.

    The new version has a simple answer, the temperature in the far room follows the external temperature, the temperature near the furnace stays steady at the temperature set by the thermostat. There is no longer an oscillatory change of anything.

    Comment by Eli Rabett — 29 Dec 2007 @ 9:28 PM

  131. #128 c is in units of time, yes, Phil. I know that already. The issue is *amplitude*, i.e. temperature. It’s not in Gavin’s “proof”.
    #129 Your attitude is disappointing, Barton. I’m here for an answer, not a fight.

    Comment by Richard Sycamore — 29 Dec 2007 @ 10:08 PM

  132. Richard, in 117 you tried to rescue your house model by complicating it beyond recognition. You now introduce a thermostat, but what is the furnace doing? Is it still cycling randomly (your original model) or is it controlled by the thermostat? You are changing furnace controls in mid argument a sure sign that you recognize the errors in your original arguments.

    The new version has a simple answer, the temperature in the far room follows the external temperature, the temperature near the furnace stays steady at the temperature set by the thermostat. There is no longer an oscillatory change of anything.

    Comment by www.r10.net küresel ısınmaya hayır seo yarışması — 29 Dec 2007 @ 11:19 PM

  133. Eli, thanks for following. Unfortunately my #130 hasn’t been approved for posting. Maybe it will show up yet.

    First, It was not me that introduced the thermostat. It was Hank.
    Second, I had to make the example more complex because Hank and Ray started burying their heads in the sand with regard to the opener, which was necessarily oversimplified.
    Third, you havent refuted my example, just poked at it.
    Fourth, when I saw the house analogy wasn’t sticking, I switched model systems. So I readily admit I will abandon any analogy if it is not working to illustrate a point. This is what you do with weaker students.
    Fifth – recalling that this is not about furnaces or human metabolismm but sun and ocean, you – like Hank, Ray, Gavin, Barton, Phil, Nick – haven’t proven raypierre’s statement.

    I’m willing to accept any rational argument that my concept is flawed. A flogging is not a rational argument.

    Comment by Richard Sycamore — 30 Dec 2007 @ 9:06 AM

  134. Richard, try this. Design a heating system for your house that uses the wintertime diurnal cycle to produce monotonic warming inside. Assume any kind of house you want and any technology, but no other heat source than the daytime sunlight.

    Then, when you have done that, imagine what features your heating system might have in common with the sun and oceans.

    Have fun.

    Comment by Pat Cassen — 30 Dec 2007 @ 11:49 AM

  135. Thermostat? Moi? Look again, the mysterious force turning your furnace on was never explained, others hypothesized a thermostat.

    Proof is available in mathematics, not in science.
    If you can express your idea as an equation, it might be provable.

    A hypothesis can’t be proved; a useful one can be tested, either by experiment or statistically.

    http://en.wikipedia.org/wiki/Image:Climate_Change_Attribution.png
    http://blogs.nature.com/climatefeedback/2007/07/sun_not_a_cause_of_global_warm.html

    If your concept is anything like the published work, consider how that’s turned out. If your concept is unlike anything published so far, you’d want to state it clearly enough that it can be tested.

    If your concept is “something might be going on that we don’t know about and you can’t prove I’m wrong” — you could be right.

    Comment by Hank Roberts — 30 Dec 2007 @ 11:50 AM

  136. This may help, it’s simple language with charts:
    http://www.quaker.org/clq/2007/TQE158-EN-GlobalWarming.html

    Comment by Hank Roberts — 30 Dec 2007 @ 12:03 PM

  137. As I said before Hank, equations are fine. Just as long as they treat the amplitude as part of the system. Gavin’s considered only periodicity of the output. That is inadequate. Your supplemental links here are interesting, thanks, but irrelevant. Apologies for attributing the thermostatic device to you. Perhaps it was Ray. Point is: my initial example had no thermostat; it wasn’t as Eli suggested, me rejigging the model because the initial one was no good. The model is an open unregulated system without feedback inhibition. A guy shoveling coal. A sun burning hydrogen.

    I don’t have a theory. Pierrehumbert has a theory. That periodic inputs can’t be flattened into a trend through integration over time by some inertial process. Proof, please.

    Comment by Richard Sycamore — 30 Dec 2007 @ 2:25 PM

  138. #128 c is in units of time,

    Comment by dijital baskı — 11 Jan 2008 @ 11:21 AM

  139. #138
    Yes, that’s what #128 Phil said: c is in units of time. When I speak of “amplitude” I want units of temperature, not time.

    Comment by Richard Sycamore — 17 Jan 2008 @ 8:39 PM

  140. Re 82- In order to demonstrate that a proposed explanation for an observed phenomenon is likely to be true, it is only necessary to show that the explanation is consistent with the known laws of physics and that it yields the observed results. It is not necessary to falsify all other possible proposed explanations (which, as we have seen, seem almost limitless!). If two explanations seem to meet this test, then there is an error somewhere that has to be thrashed out.

    Thus far, no one has come up with anything to explain the current warming that meets this test that does not include AGW as the primary component. Moreover, since the AGW explanation is so robust in terms of the physics, the observed data, and multiple lines of evidence, any proposed alternative explanation would have to show the error in the AGW analysis. And it would have to do so based, not on expert opinion, but on verifiable scientific analysis published in the peer-reviewed literature.

    So what you are getting from the busy scientists here is the real science. It is not realistic to expect them to spend time analysing speculative alternative explanations for global warming. You do it, publish it, and they will be glad to take a look at it.

    Comment by teşvik belgesi — 25 Mar 2008 @ 6:56 AM

  141. It charts both solar and temperature.
    Draw the trend line through the solar — it’s about zero.
    It goes up and down, but stays around the same level over time.
    Draw the trend line through the temperature — it goes up over time.

    Ray described the lines on that particular chart.

    Happy New Year, Ray, wherever you are. Good example, I’m going to do the same thing. Happy New Year all.

    Comment by ISO 9001 — 25 Mar 2008 @ 4:49 PM

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