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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 101051 to 101100:

  1. Lindzen and Choi find low climate sensitivity
    #77: "You cannot start with a conclusion, assume it is correct, and then derive the specific numbers ..." Indeed. We have to test the calculations that derive from a set of assumption to see if they match observation. On that fundamental point, I have no doubt we all agree. No such assumptions went into the preparation of the graphic for #57. The plotted curves are straight from the literature of radiative forcing which is not under discussion here. However, in #63, "incrementally more CO2 is not linear - but logarithmic, which means each additional amount added only has about half of the effect of the previous amount," a major flaw in your thinking is revealed. The function deltaT = 5.35 lambda log (C/C0) flattens as C (ie, CO2) increases; this gives the impression that adding more CO2 will gradually not be as bad. What you've ignored is the fact that C is a function of time that is strongly concave up. As a result, both the first and second time derivatives of the deltaT function are positive: deltaT is an increasing function of C and C is an increasing function of time. So while each additional ppm of CO2 causes a smaller temperature increase, we are adding CO2 at a rate that forces deltaT as function of time to increase at an increasing rate. Referring back to the figure in #57, your 0.6 deg C sensitivity produces neither the correct temperature anomaly nor the correct rate of change. One must therefore conclude that the assumptions made to calculate 0.6C sensitivity are incorrect, taking those calculations with them.
  2. A Merchant of Doubt attacks Merchants of Doubt
    @Kooiti - it may be that Oreskes & Conway misunderstood what Seitz was saying. But Singer has deliberately mischaracterised what O&C were saying, and framed it in such as way as to heap ridicule upon and undermine the message of the O&C book. As John said, it's the same techniques debunked by the book. Classic FUD (Fear, Uncertainty, Doubt) techniques.
  3. Lindzen and Choi find low climate sensitivity
    #83, RW1, I agree, but the bigger point is that the hemispherical asymmetry makes it impossible to use the 14 W/m^2 change and the global average temperature change as a case for much of anything and especially your last two paragraphs in #14.
  4. Lindzen and Choi find low climate sensitivity
    @RW1: "Those numbers are useless because they're all based on the assumption of a 3 C sensitivity to a doubling of CO2. You cannot start with a conclusion, assume it is correct, and then derive the specific numbers in support of it by simply back fitting calculations to your original assumption." That's not what has happened, here. Rather, multiple scenarios were proposed, and the one closest to reality (following observations) is the one that puts it in the 2-4.5C range. It is false to claim people decided that climate sensitivity was 3C, then tried to fiddle their calculations to make it fit. In fact, I'd say you're venturing dangerously close to accusations of conspiracy theories, there... Further reading: James Annan explains why sensitivity is at 3C. "Are you saying the response of CO2 is not logarithmic - but linear?" No, that's not what he's saying. Rather, he's (correctly) noting that your description of the logarithmic curve was too vague to be useful. Or perhaps you think all logarithmic scales are the same?
  5. Lindzen and Choi find low climate sensitivity
    Eric (RE: Post 78), Global average temperatures are about 3 C colder at perihelion because - yes, I think a lot of the increased power is reflected from off the ice and snow accumulations that occur in the NH winter in January. But most of the additional 14 W/m^2 at perihelion then still affects SH summer in January because at that time the SH is tilted toward the Sun.
  6. Lindzen and Choi find low climate sensitivity
    In #80, I meant to say CS is a constant that can not be subdivided.
  7. Lindzen and Choi find low climate sensitivity
    #76, chris, I think that assumes that "climate sensitivity" is a constant that can be subdivided like you are doing. My understanding is that sensitivity as it is defined here is the temperature response to a CO2 change of 280 to 560. It cannot be used for any other purpose in a linear fashion.
  8. Lindzen and Choi find low climate sensitivity
    Alec Cowan at 12:04 PM on 20 December, 2010 yes, I see your point Alec!
  9. Lindzen and Choi find low climate sensitivity
    RW1 (#73), yes, thanks, you were not referring to the last century and I thought you were. As for the difference at perihelion, my understanding is that the extra energy (14 W/m^2) falls on land masses in the NH winter which reflects away much of the extra energy (versus SH ocean which is a better absorber of solar energy). Hence the NH winter has a bit colder global average temperature than NH summer even though the energy from the sun is greater. If I am mistaken, someone will correct me.
  10. Lindzen and Choi find low climate sensitivity
    Chris (RE: Posts 60 & 70), Those numbers are useless because they're all based on the assumption of a 3 C sensitivity to a doubling of CO2. You cannot start with a conclusion, assume it is correct, and then derive the specific numbers in support of it by simply back fitting calculations to your original assumption. How about you address the series of individual questions I laid out in post 61?
  11. Lindzen and Choi find low climate sensitivity
    Eric (skeptic) at 11:50 AM on 20 December, 2010 "What is the forcing effect of incrementally more CO2?" Eric, I believe the temperature increment is proportional to the forcing increment i.e. deltaT = sigma.deltaF [where sigma is the climate sensitivity in units of oC/(W.m^2)] so I guess the forcing scales as the ln of the [CO2] increment much the same as the temperature in my post #70 above. Does that seem right?
  12. Lindzen and Choi find low climate sensitivity
    Alec (RE: Post 74), Are you saying the response of CO2 is not logarithmic - but linear?
  13. Lindzen and Choi find low climate sensitivity
    @chris #70 Why you bother? Evidently an assertion that states "logarithmic, which means each additional amount added [undetermined amount] only has about half of the effect [mensurable effect] of the previous amount." makes no sense. Don't offer your figures to people who doesn't offer them. Ask them to provide those figures. If they're commenting in good faith they'll do.
  14. Lindzen and Choi find low climate sensitivity
    Eric (RE: Post 68), Either. We know the actual total is about 238 W/m^2, and each 1 W/m^2 of that 238 W/m^2 is amplified to about 1.6 W/m^2 at the surface for a total of about 390 W/m^2. We also know that the net incident solar power is not constant - it varies by about 20 W/m^2 from perihelion to aphelion (a net of about 14 W/m^2 albedo adjusted). What I'm saying is that there is no difference between 1 W/m^2 of power from the Sun, existing or hypothetically added, and 1 W/m^2 of additional power from CO2. The AGW theory is saying that the system is all of the sudden going to respond to an additional 2 W/m^2 of power at the surface from a doubling of CO radically differently than it does the original 238 W/m^2, including the + 14 W/m^2 at perihelion, from the Sun. Understand?
  15. Lindzen and Choi find low climate sensitivity
    #69 RW1, the link in #68 shows it to be 1.5 W/m^2. Also the Lean/Rind paper.
  16. Lindzen and Choi find low climate sensitivity
    chris, when I asked about effect in #63, I should have said "forcing effect" not temperature effect. What is the forcing effect of incrementally more CO2?
  17. Lindzen and Choi find low climate sensitivity
    RW1 at 08:07 AM on 20 December, 2010
    "The response of incrementally more CO2 is not linear - but logarithmic, which means each additional amount added only has about half of the effect of the previous amount."
    That's obviously incorrect too. We can easily calculate the equilibrium temperature response expected from incremental enhancement of atmospheric [CO2]. If we use a climate sensitivity of 3 oC and normalize the Earth's temperature to near 15 oC at a [CO2] = 280 ppm, then the equilibrium temperature rise expected after each 20 ppm increment (all else being equal!) is: 
    [CO2]   equil. temp     increment
280	14.9567
300	15.2554		0.2977
320	15.5347		0.2793
340	15.7971		0.2624
360	16.0445		0.2474
    etc Clearly the assertion that "...each additional amount added only has about half of the effect of the previous amount." is quite wrong. In this case "each additional amount" adds around 94% "of the effect of the previous amount". Obviously the specific amount depends on the particular increment. So for 100 ppm increments: 
    280	14.9567
380	16.2786		1.3219
480	17.2898		1.0112
    etc.
  18. A Merchant of Doubt attacks Merchants of Doubt
    I think it is generally apt to describe Singer as a merchant of doubt. But I think it wise to avoid using this particular issue on oxygen as an example. It seems to me that originally Seitz did not mean that oxygen causes cancer by its own radioactivity, but that oxygen enhances the effects initially caused by radioactivity. If this is true, Oreskes and Conway mistook Seitz's intention, and Singer took it right. We should not blame Oreskes and Conway, however, since the wording of Seitz was obscure. We cannot blame Seitz with this particular fault, however, since his document was an internal one and also oxygen was not its main issue. So, while this may be another instance of failure of scientific communication, it can hardly play a role of a piece of evidence of malpractice of anyone.
  19. Lindzen and Choi find low climate sensitivity
    Eric (RE: Post 63), Something must be wrong with those calculations if the total isn't about 4 W/m^2 for a doubling (3.7 W/m^2 precisely). The initial 1.5 W/m^2 from 280 ppm to 380 ppm is probably wrong. It should be about 2.7 W/m^2 from 280 to 380 ppm.
  20. Lindzen and Choi find low climate sensitivity
    RW1, sorry to be a pain, are you talking about a hypothetical 1W/m^2 increase in solar forcing or actual? The actual increase over the last century was about 0.25 according to http://data.giss.nasa.gov/modelforce/ (link was in latest thread at WUWT)
  21. Lindzen and Choi find low climate sensitivity
    @RW1: plenty of people have adressed your arguments. The current increase in temperature is in line with a climate sensitivity of 3C. It is not in line with your suggested 0.6C value. As I said earlier, the burden of proof is on you, and so far you have failed to make a convincing case challenging the established science.
  22. Arctic icemelt is a natural cycle
    Natural cycle? Really? Not this year: Observations from the ground in the Eastern Arctic, ... and views taken by satellites at 500 kilometres above the earth’s surface showed ArcticNet participants that ice formation in 2010 is abnormally slow. ... “We have dramatic changes taking place,” with the Arctic becoming a place of rain instead of snow ...
  23. Lindzen and Choi find low climate sensitivity
    Eric (RE: Post 65), The reference to 1 W/m^2 of power from the Sun is already divided by 4. 1360 W/m^2 TSI divided by 4 is 340 W/m^2. Subtract out the albedo of about 0.3 and you get 238 W/m^2 of average net incident solar power at the surface.
  24. Lindzen and Choi find low climate sensitivity
    Also you (RW1) kept mentioning a 1W/m2 gain in TSI (which is mentioned in the same Lean/Rind paper). But that increase in TSI has to be divided by 4 since it is hitting a sphere not a perpendicular surface. So 0.25 W/m^2 is the increase in forcing from TSI AFAIK.
  25. It's freaking cold!
    Tom, well average for the whole winter and it was short, mild. There was a late spring snowfall in southern parts - unfortunate timing but a 30-40 year event. To my mind, a warmer world is one with more energy in the system and overall wetter. How that plays out regionally is tough call. I still dont see why the flood of cold weather reporting. Did you report the hot weather events too in summer? You say that think world is warming so what is your point in posting these. Do they challenge the consensus view? No, so why?...
  26. Lindzen and Choi find low climate sensitivity
    #32 Are you conscious that you are comparing temperatures variating in a specific place on the Earth with the average variation for the WHOLE PLANET? Do you see how wrong can be that?
  27. It's freaking cold!
    Tom, there was a time when the mainstream, status quo view was that climate change was not occurring. That view has been successfully challenged. I should say "is being," since there is still a large number of people who fail to understand the current state. You have done a pretty poor job of bringing the evidence to back up your claims. Try presenting a comprehensive counter-theory that takes into account the bulk of the instrumental data we have on atmospheric temperature (surface, TS, SS, incoming, and outgoing -- global). People might respond differently to you. You must have such a counter-theory, or you wouldn't pour so much confidence and passion into the tone of your posts.
  28. Lindzen and Choi find low climate sensitivity
    RW1 said "The response of incrementally more CO2 is not linear - but logarithmic, which means each additional amount added only has about half of the effect of the previous amount." From the 2nd link in #50 (2008_Lean_Rind.pdf) the amount of added forcing for 280 to 380 is 1.5 W/m^2 So for 380 to 480 is another 0.75 (according to your formula) and for 480 to 560 is another 0.3 (80% of 0.375) for a total of 2.55 W/m^2 (not 4) for the doubling of CO2. That hinges on your statement of "half the effect of the previous amount".
  29. It's freaking cold!
    @ Tom Löber #33 Cherry wholesaler, perhaps? You are misinforming about the supposed cold snaps and cold records in South America. That is old twisted news. I make some of my students in High School to take posts like yours and all the links they offered and dig the truth about the cold developments in 'exotic' South American territories, what was easy because we are Argentine. Suffice to say that it was a cold Winter here and there, nothing "special". State of emergency? Yes, massive anti flu vaccination (remember H1N1?). People with pneumonia -almost an average year- yes. Dead fish, yes. Other animals too. Most of them from species that moved to newly warmed territories and couldn't stand temperatures normal in 1975 or 1960. Let South America alone when in a cherry picking spree. @42 What calendar did they use in England that this is the coldest December in record? From here, it looks like 40% of December is yet to come. Maybe it's the exotic Gregorian calendar we use in South America, the continent of the cold snaps on demand.
  30. Lindzen and Choi find low climate sensitivity
    archiesteel (RE: Post 56), I'm considering 280 ppm to be the baseline - not zero.
  31. Lindzen and Choi find low climate sensitivity
    No one is answering my initial question, so I'll try to break it down into a series of separate questions: Do you agree that the albedo adjust power from the Sun is "forcing" the surface? Do you agree that increased power from additional CO2 is also "forcing" the surface? Do you agree that 1 W/m^2 of albedo adjusted infrared power from the Sun is equal to 1 W/m^2 of infrared power from CO2? Do you agree that about every 1 W/m^2 of net incident solar power is amplified to 1.6 W/m^2 at the surface for gain of about 1.6 (390 W/m^2 divided by 238 W/m^2 = about 1.6)? Do you agree that the increase in radiative forcing from a doubling of CO2 is about 2 W/m^2 (or at least 4 W/m^2)? Do you agree that in order to get a 3 C rise in temperature (288K to 291K), the 2 W/m^2 needs to be amplified to 16 W/m^2? Do you agree that 16 W/m^2 divided by 2 W/m^2 equals a gain of 8? If not, do you agree that 16 W/m^2 divided by 4 W/m^2 equals a gain of 4? Do you agree that a gain of 8 is greater than a gain of 1.6 (or at least a gain of 4 is greater than 1.6)? Do you agree that the AGW theory is saying that the system is going to amplify each 1 W/m^2 of increased power from CO2 by a much greater amount than it amplifies each 1 W/m^2 of power from the Sun?
  32. A Merchant of Doubt attacks Merchants of Doubt
    Oreskes is a historian who studies science and science policy not a scientist. My short interview with Oreskes looks at her documentation of how fossil fuel Interests, Christian Evangelicals and the Media have 'collaborated' on climate.
    Response: Actually, Naomi Oreskes is a scientist - she began her career as an exploration geologist with a degree from Imperial College (that's right, working for the mining industry). She is currently Professor of History and Science Studies at the University of California and an Adjunct Professor of Geosciences at the Scripps Institution of Oceanography. So she has a diverse background, both in practical science working out in the field and currently as a science historian.
  33. It's freaking cold!
    "Whether or not thinking life embraces free exchange of information..." There's nothing wrong with the free exchange of ideas, but that doesn't mean every idea is equally worthwhile. In this case, the fact that it's cold somewhere does not disprove AGW. What matters are global averages, and these aren't going down - they're going up.
  34. Lindzen and Choi find low climate sensitivity
    RW1 at 10:10 AM on 20 December, 2010
    "...There was only about a 0.6 C rise from 1900-2000, which is still less than a third of the 2+ C predicted"
    Nope. It's easy to do the maths RW1. Let's be very explicit. [CO2]1900 was 298 ppm. [CO2]2000 was 371 ppm.[*] The equilibrium temperature rise expected from that increase in [CO2] is 0.95 oC at equilibrium. The observed temperature rise was (1900-2000) 0.75-0.85 oC. So we're not that far off the warming expected for a 3 oC climate sensitivity already even discounting the known contributions from the inertia in the climate system and the fact that a significant amount of the warming has been offset by anthropogenic aerosols. [*]Data are from: D. M. Etheridge et al (1996) "Natural and anthropogenic changes in atmospheric CO2 over the last 1000 years from air in Antarctic ice and firn J. Geophys Res. 101, 4115 -4128 and direct measurement from the Mauna Loa station from 1959
  35. It's freaking cold!
    @Tom: "I think your interpretation of spam is extreme" No, it's not. You just posted a bunch of links with no arugment at all. That's a pretty good definition of spamming. Please continue complaining about moderation, I'm sure it'll get you somewhere. "have fun with YOUR tunnel vision" You're the one wearing blinders here, friend.
  36. Lindzen and Choi find low climate sensitivity
    I just realized why RW1 picked 1900 as his starting point: there was a spike in temperatures that year. He could have picked 1910-2010, but that would have provided a temp increase of nearly 0.9. RW1, may I suggest you stop cherry-picking dates in order to prove your point? A linear progression from 1880 to 1920 show the trend was remarkably flat, with an average that was about 0.8C colder than the present: As I said: nice try, but no cigar.
  37. Lindzen and Choi find low climate sensitivity
    Um, which natural cause are you postulating that can account for the change in ocean heat content? Thats a lot of energy to come from somewhere.
  38. It's freaking cold!
    Scaddenp, what was your last winter like? I understand there was some pretty unusual cold and snow. I see oscillations, winter to summer. I see extremes in both. I see it as a ship rocking on an ocean whose currents are being subjected to new factors, unprecedented factors the consequences of growing powerful thinking life within a finite space. Whether or not thinking life embraces free exchange of information to express intelligence may be a question as to whether or not that listing ship collapses out of what we can endure, Intelligence, fat chance, what with these linear presentations in control of folks with no or little testing of their responsibility and tolerance, seeing the little pieces that challenge status quo are given little space and much denigration, IMHO
  39. Lindzen and Choi find low climate sensitivity
    #51: "it's also just a possible it's from natural causes." That's not even a decent denial. Its possible that ... fill in the blank. You'd have some credibility if you avoided these appeals to the great unknown. #54: "Start with an assumption of a 0.6 C rise" That assumption is plainly out in left field. Here's a graphic comparing the effect of varying sensitivities to the actual temperature anomaly record: The red dots and curve are the global LOTI temperature anomaly, shifted to 0 in 1880. The curves are dt = lambda dF, for 3 values of lambda, with dF calculated from log(each year's CO2 /CO2 at start). I used CO2 values from a composite of Law Dome cores and MLO records to drive each dt function. The small number below each curve is the equivalent sensitivity = deg C/double CO2. I'm no expert at this sort of thing, but your derived sensitivity of 0.6C would fall on the lowest of the three curves. That doesn't come anywhere near close to the data.
  40. Lindzen and Choi find low climate sensitivity
    You've been shown how your math was wrong before, why do you keep repeating it? You don't get 70% of the effect from going from 300 to 380 (considering the baseline is at zero). As others have shown you, it represents just above 30%. 0.30 x 2C = 0.6C 'nuff said.
  41. Lindzen and Choi find low climate sensitivity
    RW1 at 09:45 AM on 20 December 2010
    "It's also inline with the sensitivity only being..."
    Not really RW1. And if you're going to use the non-argument that (paraphrasing) "anything is possible...we just don't know", why bother to attempt a (incorrect) quantitative argument in the first place!? I would have thought what you said earlier is appropriate:
    "The scientific method dictates modifying or discarding a hypothesis when it does not fit the evidence. It does not permit adding unsubstantiated things arbitrarily after the fact when the hypothesis is not in accordance with the evidence.
    Your odd hypothesis (that empirical observations are incompatible with the value of climate sensitivity that best fits the empirical evidence) is wrong (you mistakenly used faulty maths and logic). So you should "modify or discard" your hypothesis. You shouldn't "add unsubstantiated things arbitrarily after the fact". The empirical evidence simply doesn't support the unsubstantiated assertion that "...it's also just as possible it's from natural causes".
  42. It's albedo
    Re: Rovinpiper (24) Barton Paul Levenson has addressed some of Ferenc Miskolczi's misconceptions here. The Yooper
  43. Lindzen and Choi find low climate sensitivity
    chris (RE: post 50), All those calculations are starting with the input assumption of a 3 C rise in temperature from a doubling of CO2. Start with an assumption of a 0.6 C rise and you're going to get a completely different and much lower result. Maybe the amount of CO2 was closer to 300 ppm in 1900 instead of 280 ppm. Still 300 ppm to 380 ppm equals about 70% of the forcing from a doubling of CO2, which still should have been over a 2 C rise in temperature. There was only about a 0.6 C rise from 1900-2000, which is still less than a third of the 2+ C predicted.
  44. A Merchant of Doubt attacks Merchants of Doubt
    @Bob: right. This isn't about the science of AGW, but about the political opposition to the science, and the means used by powerful corporate interests to bury the truth in order to protect their bottom line.
  45. It's freaking cold!
    @Tom: what you believe is irrelevant. The fact that you are spamming worthless anecdotal evidence is the problem.
  46. Lindzen and Choi find low climate sensitivity
    Also, be sure to read Chris' excellent rebuttal of your untenable position. Hey, you gave it a shot...
  47. Lindzen and Choi find low climate sensitivity
    @RW1: "Vostok is in Antarctica - not the Arctic, which I know is more variable than global averages. Antarctica is considerably less variable than the Arctic. Even if you assume the global averages were only half of what Vostok depicts, that still means the amount of warming we've seen is only about average or maybe a little above." In other words, you do not have conclusive evidence that there have been other increases that were just as dramatic in the past (barring catastrophes). So, in the absence of evidence, we have to continue assuming that the current warming is unprecendented, *especially* since we can't identify other causes but for CO2. "It's also inline with the sensitivity only being about 0.6 C" Actually, it isn't, because not even all fast feedbacks have kicked in yet, let alone slow feedbacks. "or any other amount for that matter, including zero." Now you're not even making any sense. Typical of contrarians: in like a lion, out like a lamb. "Again, you're assuming virtually all the increase we have seen is from CO2." As is likely, as per the observed evidence. There is simply *no* other explanation for this warming, depsite your wishful thinking. "While that is possible, it's also just a possible it's from natural causes." There is no evidence supporting the latter. Personally, I like to go where the evidence is. Come back whenever you figure out what these mysterious natural causes are...
  48. It's albedo
    Hi Ned, For our purposes he is "skeptical" about the ability of light-reflecting aerosols to lower Global Mean Temperature. He seems to be saying that a change in the reflectance of an object in a constant electromagnetic field will not change its equilibrium temperature. This is because the emissivity of said object will increase. He says that his personal friend Ferenc Miskolczi has a paper positing this which has never been refuted. I have a link to Miskolczi's work. Unfortunately, the material is too complicated for me to read. It might as well be written in context free grammar as far as I'm concerned.
  49. It's freaking cold!
    I believe we are experiencing global warming. Who said i didn't? I also believe climate is dynamic and expecting only slow global warming could be a disastrous mistake but, if it doesn't fit what you want to believe, then, by all means, do the junk yard dog dance.
  50. Lindzen and Choi find low climate sensitivity
    archiesteel (RE: Post 47), It's also inline with the sensitivity only being about 0.6 C - or any other amount for that matter, including zero. Again, you're assuming virtually all the increase we have seen is from CO2. While that is possible, it's also just a possible it's from natural causes.

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