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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 101001 to 101050:

  1. Arkadiusz Semczyszak at 21:36 PM on 20 December 2010
    A Merchant of Doubt attacks Merchants of Doubt
    @rockytom S funding of research related to AGW is a "slippery subject" ... : “Even the big oil companies have long since been putting their real money into projects dedicated to showing how they are in favour of a "low carbon economy". In 2002 Exxon gave $100 million to Stanford University to fund research into energy sources needed to fight global warming. BP, which famously rebranded itself in 2004 as "Beyond Petroleum", gave $500 million to fund similar research.[...]”
  2. Lindzen and Choi find low climate sensitivity
    #112 VeryTallGuy, if we said 1000 years that would give us 4000 year watts / m^2. I don't think year watts has any physical meaning. #105 RW1, I don't think there is any other explanation of the year-to-year rise in OHC other than CO2 forcing despite the annual fluctuation due to app/peri. It is the same idea as the steady rise in atmospheric CO2 despite the seasonal fluctuation which exceeds that rise. The only explanation of the year-to-year increase is man-made CO2 in the atmosphere being only about 1/2 absorbed over the year and the other 1/2 remaining.
  3. Lindzen and Choi find low climate sensitivity
    #108 muoncounter, the plot in 108 does not show annual cycles. This paper does ftp://ftp.nodc.noaa.gov/pub/data.nodc/woa/PUBLICATIONS/grlheat04.pdf and shows a 3 x 10^22 J annual fluctuation (zero to peak) or about 3 times the average annual rise of the plot in #108
  4. Stratospheric Cooling and Tropospheric Warming - Revised
    The Ville #44 "what exactly do you mean by a packet of energy." As the context is electromagnetic radiation, and the exchange of heat from solids on the ground to CO2 molecules that make up the atmosphere, it is hard to understand where the obscurity lies. My point has been fairly straightforward, but if I lost someone (and by the way, it seems odd you are so sure what others may or may not understand), I suppose it can be worded anew. Let's see. If an IR "photon", energy packet, (however you want to call it) is emitted from a roof's slate shingle, and is captured by a CO2 molecule two feet away, has not the roof lost the energy, and the air gained the energy? And in losing this energy, has not the roof effectively "cooled"? Now with this question, I am not attempting offend, bait, or work up my ego as you say. My intention is to simply point out what to me looks inconsistent with what is understood to be "global warming", a term which in itself is hiding something. Global "surface" warming?, global "atmospheric" warming?, global ocean warming???. Which is it? Yes. The replies I have received so far are saying global "everything" warming, (even though of late, the idea that the stratosphere is cooling has come forward.) And these replies include nonsense about how CO2 in acting like an isotropic antenna is synergetically increasing the "Earth's" temperature. I would be nice if in these explanations it was clearly stated what exactly is warming, and how this actually happens. About the only accurate thing I read above was the words, "fictitious model".
  5. Lindzen and Choi find low climate sensitivity
    Riccardo yes, I agree with everyrthing you say. Just thought the rough calc might help to explain.
  6. Arkadiusz Semczyszak at 20:59 PM on 20 December 2010
    Greenland Ice Sheet outlet glaciers ice loss: an overview
    “... please furnish a concluding summation ...” Sorry to reply so late ... The conclusion is simple and obvious after all - the Arctic - the current changes, as a whole, the melting ice in Greenland and the Greenland Sea, severe winters in Europe, Canada, USA and central China, this is an example of a decisive influence: direct and indirect - of solar activity. The current accelerated melting of ice in NH - it is even (according to some authors, the above-mentioned papers) to 91% - just nature. Contrary to appearances, the tropics and Antarctica - SH, contain the best examples of the potential GHG RF! By the way you see - a comparison of the Eemian - Greenland ice - that physicists of atmosphere do not know what it is: "post-glacial rebound" (...). ... and paper: Overland, Wang, and Walsh, 2010.: blog news - frequently asked question: since at least 2003, and especially in 2007 - it was a record warm in Greenland - similarly, with regard ice (mass, area) - why then the winters in the temperate zone NH were warm?
  7. Lindzen and Choi find low climate sensitivity
    VeryTallGuy it's even worse than that. The climate system does not have time to fully respond to a 6 months forcing; also, 14 W/m2 is the maximum peak-to-peak value and it should be average over half a cycle. You badly exagerated the response to the annual cycle :) Anyways, it's true that the NH winter would be a little worse if it occured at the aphelion.
  8. Stratospheric Cooling and Tropospheric Warming - Revised
    RSVP said: "By double time, I am referring to a single packet of energy. If it gets into the air via CO2,(coming from a hot stone on the ground), the hot stone has just lost that heat. That is not double time. That is heat transfer." Firstly most people have a hard time decoding what on earth you are trying to convey and you return the favour to everyone hear by posting a number of replies by revealing more in a critical and patronising fashion. In future, if you get a number of responses and don't get an answer consistent with what you were expecting. I suggest you actually clarify your original query. RSVP said: "Most of this incoming energy is in the visible band, so the exchange you are talking about is favor of the stone getting a much larger share of it. And as far as the stone's cooling by radiating IR upward, the more CO2 above it, the bigger the sink for that IR." Indeed, does your ego feel better now?
  9. Stratospheric Cooling and Tropospheric Warming - Revised
    RSVP @41 Why not do the calculation yourself - what's the difference in heat capacity for an atmosphere with 560 vs 280 ppm CO2?
  10. Stratospheric Cooling and Tropospheric Warming - Revised
    RSVP: "The stone absorbs energy in the visible portion of the electromagnetic spectrum, CO2 does not (which accounts for it not being visible, unless cold enough to become dry ice)." You referred to a packet of energy, you did not refer to any particular flavour. I suggest in future that you make it clear what on earth you are talking about and what you mean. For a start, what exactly do you mean by a packet of energy. eg. if you want to be precise, then be precise, if you are talking about general principles then do so. But don't hide your intentions and play dumb games that you know are intended to disrupt without a view of making progress or helping others to understand. If you are not interested in the subject then leave the classroom and sign up for another course.
  11. Lindzen and Choi find low climate sensitivity
    Oh, and here's a way to think about the 14W/m2 perihelion point you made to start with. 4W/m2 over (say) 100 years = 400 year watts/m2 energy change 14 W/m2 over 6 months = 7 year watts/m2 energy change So the effect of doubling CO2 over a century is 57x larger than the energy imbalance during the year. Assuming your unreferenced 14 W/m2 is correct - I haven't checked it and you haven't provided a reference.
  12. Lindzen and Choi find low climate sensitivity
    RW1 @39 (in reply to my 38) You completely fail to understand what the 4W/m2 represents. Your point 5 implies that 4W/m2 is the upwards flux from the surface absorbed in the atmosphere, some of which goes up and some down. This is mistaken. 4W/m2 is the net change in power emitted at the top of the atmosphere. The number is the result of a stepwise line by line heat balance; your point that CO2 radiates in all directions equally has already been taken care of in the calculation. Repeating this ad nauseum does not make it correct. You cannot halve it just to make your calculation yield the result you want it to.
  13. Stratospheric Cooling and Tropospheric Warming - Revised
    #40 RSVP at 17:22 PM on 20 December, 2010 "The only unexcited CO2 molecule I can imagine is one at zero Kelvin." The most CO2 molecule be unexcited. The ratio unexcited CO2 molecule to excited CO2 molecule is given from Boltzmann-Distribution exp(-hv/(kT)).
  14. Lindzen and Choi find low climate sensitivity
    Seriously, not only do you have the same writing patterns as damorbel, you seem hell-bent on using the same tactic: repeat your erroneous ideas over and over again, ignoring rebuttals, in order to waste everyone's time. Put up or shut up: provide concrete evidence that the current warming *isn't* caused by CO2, or go do something else with your precious Internet time. Whatever you do, *don't* start over with another user name - we can see right through that.
  15. Lindzen and Choi find low climate sensitivity
    @RW1: "I'm well aware that any CO2 warming will be in addition to, or on top of, the normal variations. I don't dispute this, and nothing I've written disputes it." Then why do you act as if that wasn't the case? It matters little that CO2's additional forcing is 30% of the seasonal variation. What matters is that the average global temperatures go up. "I'm saying there is no physical reason why the globe as a whole would respond any slower than the individual hemispheres do to increases in radiative forcing." Actually, there is a very simple reason. The cyclical changes revert back and forth too quickly to trigger any feedback. On the other hand, increasing global temperatures nudges the cycle out of its rut, triggering feedbacks. Anyway, the point is moot. You have failed to come up with any credible alternatives to CO2 for the current warming. I don't understand why you continue to act as if you had a leg to stand on, because you don't.
  16. Stratospheric Cooling and Tropospheric Warming - Revised
    #40 "So the only thing that can happen if one CO2 dumps some energy to another is for both to get less excited (i.e. cooler). " correction of my own post... One will get a little more excited, and the other a little less excited. However, the net temperature should remain unchanged.
  17. Stratospheric Cooling and Tropospheric Warming - Revised
    JeffT #32 "The result of increasing CO2 is an imbalance: solar energy is still arriving, but it's not leaving as fast." If you douse a campfire with water, in order to quench it faster, do you pour more, or less water? Normally the concern in such occasions is not how hot the water gets, but in any event, the more water you dump, the less it will warm on the whole. This is because the more water you dump, the more thermal mass you are providing for transfering heat from the embers and stones to the water. Why doesnt this happen to CO2 as the concentrations increases? Afterall, isnt the amount of energy coming from the Sun the same?
  18. Stratospheric Cooling and Tropospheric Warming - Revised
    The Ville #30 "CO2 is no different to a hot stone" The stone absorbs energy in the visible portion of the electromagnetic spectrum, CO2 does not (which accounts for it not being visible, unless cold enough to become dry ice). The Ville #30 "The stone is continually receiving packets of energy (during the day), as would the CO2." Most of this incoming energy is in the visible band, so the exchange you are talking about is favor of the stone getting a much larger share of it. And as far as the stone's cooling by radiating IR upward, the more CO2 above it, the bigger the sink for that IR. Alec Cowen #31 "What makes you think that the post is saying something like what you are describing... " The article states "The interaction of IR radiation with CO2 is a two way street in that IR radiation can interact with unexcited CO2 molecules and cause them to vibrate and become excited and excited CO2 molecules can become unexcited by releasing IR radiation." I mentioned dry ice and the article talks about an "unexcited CO2 molecule". The only unexcited CO2 molecule I can imagine is one at zero Kelvin. Dry ice forms way above that, and CO2 in its gaseous state is at a still higer temperature and generally speaking, excited. So the only thing that can happen if one CO2 dumps some energy to another is for both to get less excited (i.e. cooler).
  19. Stratospheric Cooling and Tropospheric Warming - Revised
    His words:
    "Since 1996, lunar eclipses have been bright, which means the stratosphere is relatively clear of volcanic aerosols. This is the longest period with a clear stratosphere since before 1960."
    So what, exactly, is the point of your comment, Camburn? Because it seems to be along the lines of:
    "I drink coffee and marsupials have legs"
    To put confidence into a presentation at a conference funded by a petroleum-shill instead of work vetted in peer-reviewed publications by actual working climate scientists speaks volumes... An analysis of Keen's other body of work can be found here. The Yooper
  20. Lindzen and Choi find low climate sensitivity
    #107: "it doesn't take much time at all to change ocean heat content" Do you have any documentation for that? Again, credibility comes from being able to substantiate of your claims - preferably with reference to actual scientific literature. We're not talking about the surface temperature, despite your (similarly unsupported) claims to the contrary. Looks like a long, slow, but steady climb to me. No hint of seasonal variability.
  21. Lindzen and Choi find low climate sensitivity
    KR (RE: Post 106), Apparently, it doesn't take much time at all to change ocean heat content. If it did, we wouldn't see anywhere near the seasonal variability each year, nor especially would we see anywhere near the change in ocean temperatures the occur each year. I'm not saying the seasons make any long term changes, as they do average out globally. I'm saying there is no physical reason why the globe as a whole would respond any slower than the individual hemispheres do to increases in radiative forcing. Ocean water is ocean water - whether it's in one specific hemisphere or the whole globe. Or are you saying the fundamental physics of ocean water is different hemispherically than it is globally?
  22. Stratospheric Cooling and Tropospheric Warming - Revised
    This is an interesting observation by Dr. Keen: http://spaceweather.com/ all clear in the stratosphere.
  23. Lindzen and Choi find low climate sensitivity
    RW1 - In detail? Nothing much to say other than 'time constants'. It takes time to change ocean heat content, which drives much of global weather. It takes time to melt or freeze the Arctic and Antarctic, to change the state of glaciers and Greenland, to change the distribution of plant zones. And seasonal changes, unlike CO2 forcings, happen too fast to make those long term changes. They cycle up and down (like weather) too fast to affect long term issues like those. There's nothing mysterious about that. It's all a matter of thermal inertia.
  24. Arctic sea ice has recovered
    Heh! I'll put my surfboard on my little deuce coupe as I head North To Alaska, where the curl of the Arctic swells generated by the 6-month long summer Arctic Dipole warms the toes of the windsurfers cruisin' the Northwest Passage to Baffin Bay, where the scenery is beautiful and the women...did I mention the scenery? BTW, the longer you stare at the chart, the more it resembles someone diving in the water... The Yooper
  25. Lindzen and Choi find low climate sensitivity
    KR (RE: Post 103), That's my point, why are they separate? Why are they different. What specifically is physically different about increased radiative forcing on a seasonal/hemispheric basis and increased radiative forcing globally? And don't point me to some graph. Even if I assume the information in that graph is correct, it doesn't mean the rise is from increased CO2 radiative forcing. What I mean is explain the physics in detail.
  26. Lindzen and Choi find low climate sensitivity
    RW1 - also Figure 5 from that last posting.
  27. Lindzen and Choi find low climate sensitivity
    RW1 - "How can the response time be 40+ years globally but only be about one month seasonally and/or hemispherically?" By actually considering the separation between short term seasonal feedbacks and long term heat content (Figure 4).
  28. Lindzen and Choi find low climate sensitivity
    KR (RE: Post 100), @KR: "Please keep in mind that the perihelion/aphelion cycle is just that - a cycle. Which means it goes down as well as up." I know. @KR: "The added greenhouse effect, on the other hand, is a long term increase in both perihelion and aphelion irradiance, a long term uncompensated change in total irradiance. And hence an energy imbalance." I also know. @KR: "The climate response to shifts in overall irradiance appears to be (including ocean responses) at least 40 years for mid-length feedbacks, centuries for long-term (weathering) feedbacks." How can the response time be 40+ years globally but only be about one month seasonally and/or hemispherically?
  29. Arctic sea ice has recovered
    Yooper, We count on you to be first with the good news. Those bottom curves (August-September) dropped 50% (from 10000 to 5000) in just 3+ years! Never mind Lake Superior, you'll be body surfing Baffin Bay in no time.
  30. Lindzen and Choi find low climate sensitivity
    #96: "I mean only the intrinsic radiative forcing response - not any theoretical increase in temperature" In reality, isn't it the temperature increase that matters? The fact is that we have already observed more warming than your albedo-adjusted model predicts. In essence, you call for 0.3deg warming due to CO2 radiative forcing. To account for the observed 0.8deg global (1.0deg in the northern hemisphere), you must therefore invoke 'unknown forces' or 'natural causes' for more of an effect (0.8 observed - 0.3 CO2 = 0.5 unknown) than you calculate. I would be deeply troubled if that is where my calculations left me.
  31. Lindzen and Choi find low climate sensitivity
    RW1 - Please keep in mind that the perihelion/aphelion cycle is just that - a cycle. Which means it goes down as well as up. The added greenhouse effect, on the other hand, is a long term increase in both perihelion and aphelion irradiance, a long term uncompensated change in total irradiance. And hence an energy imbalance. The climate response to shifts in overall irradiance appears to be (including ocean responses) at least 40 years for mid-length feedbacks, centuries for long-term (weathering) feedbacks. The perihelion and aphelion cycles average out over those time scales. CO2 does not.
  32. Lindzen and Choi find low climate sensitivity
    archiesteel (RE: Post 95), I'm well aware that any CO2 warming will be in addition to, or on top of, the normal variations. I don't dispute this, and nothing I've written disputes it. Also, I know temperatures are affected by the seasons - I've written so multiple times in this thread. The +14 W/m^2 at perihelion is a global average addition - not isolated to just one hemisphere or the other.
  33. Lindzen and Choi find low climate sensitivity
    RW1 - No, CO2 at the poles will act like CO2 at the tropics - retaining a percentage of the thermal radiation at those locations. That's a bogus argument. As to water vapor - that's a feedback to any forcing, whether it's CO2 or solar or aerosol. It doesn't counteract CO2 forcing in itself. If you wish to argue for a cloud feedback, take it to the cloud sensitivity thread.
  34. Lindzen and Choi find low climate sensitivity
    muoncounter (RE: Post 85), I meant post 96 above to be in response to your post 85 (not 86).
  35. Lindzen and Choi find low climate sensitivity
    muoncounter (RE: Post 86), I now see the problem. When referring to the logarithmic response of CO2, I mean only the intrinsic radiative forcing response - not any theoretical increase in temperature in addition to the intrinsic response via potential feedbacks and so forth (i.e. a 3 C rise). The intrinsic increase in radiative forcing from a doubling of CO2 is 3.7 W/m^2. When I say we've already reached 70-80% of a doubling going from 300 to 380 ppm (or 280 to 380ppm), I mean 70-80% of 3.7 W/m^2 or about 2.6 to 2.9 W/m^2 of intrinsic forcing.
  36. A Merchant of Doubt attacks Merchants of Doubt
    Stephen and John at #6 Oreskes was definitely a working scientist. I remember a particularly interesting review of numerical models in geology that was published in Science in the 90's. I was surprised when I saw her being referred to as a historian a decade later. I think Kooti is probably right about Seitz's original intentions and O&Cs mistaken take on it - though we don't really have context so it's really hard to tell. But Bern is also right that Singer is dead wrong and likely insincere in his interpretation.
  37. Arctic sea ice has recovered
    Despite the offseason, Neven's blog (Arctic Sea Ice) continues to produce tasty morsels, like this comment by FrankD:
    "What comes out? A better than 50% probability of an ice free September by 2016, with the ice free period increasing by almost a month each year. By 2023, there is a good likelihood of five months ice free, from mid-July to mid December. After that it slows down somewhat, but March and April, the last months remaining, reach zero around 2032-33.
     Which he then links to the chart he created here: Melt season 2011 will be something to behold, now that Cryosat-2 is pumping out data... The Yooper
  38. Lindzen and Choi find low climate sensitivity
    @RW1: "My main point is the aggregate confluence of factors that actually determine global average temperatures don't appear to be even phased much by 14 W/m^2 increase in radiative forcing - an amount much larger than what would come from a doubling of CO2." Temperatures are very much affected by the seasonal effect - that's why we have seasons! The warming due to CO2 is in addition to the normal variations. That's why it matters. Also, RW1, by not responding to muoncounter at #85 you are ignoring a strong rebuttal to your argument. Are you conceding defeat?
  39. Lindzen and Choi find low climate sensitivity
    Eric (RE: Post 93), Well yes, but the polar regions are also largely snow and ice covered, which means a lot of the incoming power is getting reflected back out (back through the CO2), so incrementally more CO2 in those areas won't do much at all. Also, if there is a global increase in temperature from CO2, there will likely be a global increase in water vapor. That should offset any increase in CO2 for areas in the polar regions not snow and ice covered - as far as water vapor/CO2 absorption overlap is concerned.
  40. Lindzen and Choi find low climate sensitivity
    Because there is less water vapor in the polar regions so CO2 has a proportionally greater effect and so a change is CO2 would also have a greater effect than outside of polar regions. As for using average numbers, I'm not a big fan of those for many reasons, one of which is demonstrated in your #14 which didn't mention the large differences in seasonal responses between the hemispheres.
  41. Lindzen and Choi find low climate sensitivity
    Eric (RE: Post 91), Why would CO2 have more effect in the polar regions? The numbers I've used throughout are global average numbers.
  42. Lindzen and Choi find low climate sensitivity
    The "radical" difference comes from the difference in the way the two hemispheres respond to the seasonal solar changes. There's no way to get away from that fact and it means that the global average temperature response to CO2 which is evenly distributed worldwide, has more effects in polar regions, etc, is going to be radically different. It's sort of like saying that a giant fire in one hemisphere is going to have the same effect as a lot of smaller fires adding up to the same amount of heat and smoke, but distributed worldwide. Clearly the effects on weather and thus temperature will be quite different in those two cases.
  43. Lindzen and Choi find low climate sensitivity
    Eric (RE: Post 88), That last paragraph in my post 89 should have read: The perihelion point aside, what is so special about each 1 W/m^2 of increased power from CO2, that the system is all the sudden going to respond to it radically differently than it does each 1 W/m^2 of power from the original 238 W/m^2 sourced from the Sun?
  44. Lindzen and Choi find low climate sensitivity
    Eric (RE: Post 88), I agree that the difference between the hemispheres is one of the main reasons, but the whole climate is affected (i.e. about 3 C colder globally at perihelion - not just in the NH). Without the +14 W/m^2 at perihelion, the global average temperatures would probably be even colder in January than they are now. It should also be pointed out that global temperatures are actually 3 C warmer at aphelion in July when net incident solar power is about 14 W/m^2 less. My main point is the aggregate confluence of factors that actually determine global average temperatures don't appear to be even phased much by 14 W/m^2 increase in radiative forcing - an amount much larger than what would come from a doubling of CO2. The perihelion point aside, what then is so special about each 1 W/m^2 of increased power from CO2, that the system is all the sudden going to respond to it radically differently than it does each 1 W/m^2 of power from the original 238 W/m^2?
  45. A detailed look at climate sensitivity
    Hopefully this will answer chris on the Lindzen thread. Disregarding my critique of paleo studies of sensitivities above, I still do not believe that we can take a sensitivity calculated in paleo records and use it in a linear fashion. For one thing the paleo sensitivities reflect long term correlation which may be somewhat linear. For example as oceans warm over hundreds or thousands of years, CO2 is released in a more or less linear fashion. But the short term is nonlinear. Short term sensitivity is based on water vapor feedback. But water vapor feedback is highly nonlinear as evidenced by daily tropical weather cycles and seasonal changes in weather (larger NAO fluctuations in winter than in summer is just one of many examples). The sensitivity that was based on long term factors shown in the ice cores has nothing to do with a sensitivity based on the short term factors. Furthermore, neither sensitivity is applicable to our current interglacial regime. The longer term sensitivity only applies to glacial to interglacial transitions. So an attempt to use that sensitivity for a current increase (50%, doubling, or other) in CO2 requires waiting for the long term responses (centuries at least) and won't show up in a few decades of data.
  46. Lindzen and Choi find low climate sensitivity
    RW1, the 0.3 value may be an average over all seasons, but the effective albedo must be greater in January since the solar forcing is greater but the global average temperature is lower. My parenthetical statement about the SH oceans in #78 is probably incorrect. But my main point again is that your statement in #14 "That the global climate doesn't even appear to be phased by a 14 W/m^2 increase in radiative forcing, suggests the net feedback operating on the system as a whole is strongly negative - not positive,..." is not a logical conclusion. The reason why the global climate is not affected by the 14 W/m^2 is due to the differences between the hemispheres, not net global feedback.
  47. Lindzen and Choi find low climate sensitivity
    Eric (RE: Post 84), Why not? OK, so it's not about 14 W/m^2 net - but something less because the total albedo in January is greater than 0.3 you're saying?
  48. Lindzen and Choi find low climate sensitivity
    Eric (skeptic) at 12:29 PM on 20 December, 2010 I don't think that's right Eric. The climate sensitivity is defined by convention as the amount of warming at equilibrium resulting from a radiative forcing equivalent to a doubling of atmospheric [CO2]. But it can be (and is) used to determine the equilibrium temperature response expected from any change in forcing including that resulting from small increments of [CO2]. Clearly if the wealth of empirical data supports a climate sensitivity near 3 oC (say), then the warming contribution expected from a rise of [CO2] from 280 to 380 ppm (say), should be predictable within that climate sensitivity (according to the ln of the ratio of [CO2]s). It would be perverse to consider otherwise. Of course the climate sensitivity is obviously a shorthand estimate of a response in a complex world! So the climate sensitivity in a world with a certain amount of sea ice (say) will differ from that of a world with no sea ice (say), since the albedo feedbacks will differ. In the real world the "climate sensitivity" will likely "dance around" somewhat temporally and according to precise conditions. ----- O.K. I've just seen your correction so maybe my post doesn't quite address your point. But (re your correction), the climate sensitivity isn't being subdivided. We're considering the Earth's equilibrium temperature response to a forcing as parameterized within a single value of the climate sensitivity. What's being subdivided is the forcing and its response, not the CS! I suspect that we might be talking at cross purposes, btw! If you think I haven't addressed your point properly have another go and I'll try again in the morning.
  49. 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.
  50. 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.

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