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Comments 72601 to 72650:

  1. There is no consensus
    Sky, We already answered that on the other thread - yes. The discussion here is about whether we can say that there is a consensus among scientists as to the sensitivity of the temperature to CO2. We have already agreed that exact value in unknown, and that there is a plausible range of values. The disagreement is about what is that range, and is it narrow enough to constitute a consensus. Your range for the Hubble is much narrower, and not being a cosmologist, I cannot appropriately answer your question. Biblio, If we are talking about short-term transient sensitivity, then the plausible values are much lower, and Hansen's value of 3 is still on the high side. The following might help clear this up for you. http://profmandia.wordpress.com/2011/01/18/clearing-up-the-confusion-about-climate-sensitivity/ http://journals.ametsoc.org/doi/abs/10.1175/2011JCLI3989.1
  2. Eric (skeptic) at 22:09 PM on 14 October 2011
    Pielke Sr. and SkS Warming Estimates
    Re #88, in #40 Dr. Pielke said: In fact, you are inappropriate mixing a "forcing" from a "change in forcing over some time period". A forcing (such as produces an acceleration, is immediate). He explained earlier in the post that some forcings are radiative and some are not, giving an example from the NAP book http://www.nap.edu/openbook.php?record_id=11175&page=40 In the post he was replying to, #37, Tom Curtis quoted from the AR4 glossary that a forcing is a change in net irradiance "due to a change in an external driver of climate change" such as a CO2 change or TSI change. IMO the only confusion is between the direct forcings of AR4 and the indirect forcings from NAP. But in both cases (and Tom's 37) they are referring to a change in forcing, not the forcing itself (so no inappropriate mixing was done). Nonetheless I did not those particular indirect forcings addressed in any subsequent posts (the ones from the NAP book I linked above) although MA Rodgers also asked about them. It seems appropriate to ask for the direct forcings and the radiative imbalance of direct and indirect forcings as distinct questions.
  3. Continued Lower Atmosphere Warming
    DK @6, It's obvious by just looking at the couple of graphs above that nul hipothesis to Pielke's conclusion passes easily here. Santer et al. (2011) have proved it; no need to repeat. Certainly, dr. Pielke seems to disregard statistical methods while formulating his conclusions. Further, by cherry-picking the weather data that is likely to support skeptic opinion and ignoring the other aspects of the warming globe, (i.e. ocean heat, discussed here); he shows a biased attitude. We know many examples of such cherry-picking by many "skeptics". The most prominent one being Chris Monckton, who not so long ago (as lately as April 2011 in Australia) boasted that "Arctic is steadily gaining ice" showning the ice extent data for years 2007-2009 as the "proof". We all know now that Monckton was not only cherry-picker but a [-snipped-] because he didn't even show the 2010 data (available to him at the time) as that data would disprove his claim. Now, when the 2011 ice data equalled the record low of 2007, no one listens to Monckton's [-snipped-] anymore. It's easy to rebut Monckton (his arrogance also works against him), Pielke is more subtle but still uses the same cherry-picking methods.
  4. Pielke Sr. and SkS Warming Estimates
    Did we ever get to the bottom of Pielke Sr's interpretation of Forcing @40? I.e. "A forcing is ... immediate" and different from "a change in forcing over some time period" Immediate or not, a force is still a change from before to after. I did wonder if Pielke Sr was talking of some measure of residual forcing (radiative imbalance) when asking for the forcing for 2011 but @8 he asks for the 2011 forcing and radiative imbalance as well. So I am at a loss at what he is blethering on about. Is there some refined climataligical definition of 'forcing' that I am misinterpreting or is this our pet sceptical professor of climatology making yet another 'simple mistake on a fact you would expect him to know well'.?
  5. The Earth continues to build up heat
    Thanks Rob, I look forward to seeing what you have to say. p.s. I don't think that it's coincidental that the recent extremes in weather we're seeing have occured since the precipitous decline in the arctic sea ice in 2007.
  6. The Earth continues to build up heat
    atcook27 - I have assumed until now that the oceans were largely being warmed by the heat in the atmosphere. I don't think you're alone in that regard. Quite conveniently I have a post on that topic coming up in a couple of days time. It's the sun that warms the ocean, but greenhouse gases regulate the amount of heat they retain. The post should be published on Sunday.
  7. The Earth continues to build up heat
    I have assumed until now that the oceans were largely being warmed by the heat in the atmosphere. I believe that this graph points to a different conclusion. It would seem that the energy increase in the ocean is much larger in scale than that of the atmosphere. If you take into account that water is much harder to warm than air, it would seem impossible that the atmospheric warming alone has been responsible for the oceanic warming. So where is the energy to warm the oceans coming from? There is only one major source....the melting of the arctic sea ice. I believe that the albedo effect has been grossly underestimated. If this is the case then we are in a heap of trouble as the magnitude of this effect is set to double over the next decade as the arctic eventually becomes ice free in the northern summer.
  8. The Earth continues to build up heat
    Michael Hauber - "Although squinting at the colours with my partially colour blind eyes, it looks like the strongest heat gain is in the Atlantic?" Heat from the Indian Ocean is leaking into the Atlantic. See: What caused the significant increase in Atlantic Ocean heat content since the mid‐20th century? - Lee (2011) Not the 700-2000 mtr layer though. It'd be really nice, to see a review paper putting all this into context.
  9. Pielke Sr. and SkS Warming Estimates
    I'll just note couple of papers regarding the carbon dioxide - water vapor overlap issue: Pielkesr: "It is my specific question that an answer is needed for "What would be the global annual average radiative forcing change since pre-industrial with CO2 without the water vapor overlap and with the the overlap?" I doubt you could find it in a literature search because to my knowledge, it has not been done." There is a classic paper by Kiehl & Trenberth (1997), which seems to address this question at least in some form: "It is also important to note that different gases can absorb radiation at the same wavelengths; this is called the overlap effect." Then, later in the paper: "Of this 125 W m-2 clear sky greenhouse effect, we can ask, what is the relative contribution of each atmospheric absorber? A detailed answer to this question is complicated by the overlap among individual gaseous absorption features. We calculate the longwave radiative forcing of a given gas by sequentially removing atmospheric absorbers from the radiation model. We perform these calculations for clear and cloudy sky conditions to illustrate the role of clouds to a given absorber for the total radiative forcing. Table 3 lists the individual contribution of each absorber to the total clear sky radiative forcing." Table 3 then gives for each included gas the individual and combined effects for both clear and cloudy sky. For carbon dioxide individual clear sky radioative forcing is 29 watts per square meter and combined (with overlap effects) forcing is 32 watts per square meter. There is also separate row for "Overlap H2O–CO2". Another paper apparently addressing this issue is Cess et al. (1993). However, I I only have seen the abstract, so I'm not sure how complete analysis this paper has. I just noticed that Google Scholar returns this sentence for this paper: "Fig. 3. (A) Scatter plot of LW clear (clear sky) radiative forcing, as generated by the GCMs, with and without overlap of the C02 absorption bands by water vapor absorption." So it seems that it might be interesting in this sense. If needed I can dig up more references as there seems to be plenty of research done on this overlap issue.
  10. Continued Lower Atmosphere Warming
    skywatcher - I believe that graph was a Dr Inferno masterpiece at DenialDepot.
  11. Dikran Marsupial at 14:51 PM on 14 October 2011
    Pielke Sr. and SkS Disagreements and Open Questions
    Prof Pielke wrote: "Dikran Marsupial - I had three hypotheses. I request you complete the test and see what you obtain." I do not dispute the fact that your first two hypotheses are entirely true, however, as I pointed out neither of these facts are at all surprising because the timescale over which the trends are calculated are too short for us to reasonably expect to be able to reject the null hypothesis even if it is false. Thus the test, and therefore the hypothesis, is essentially meaningless. Statistical power is often neglected by working scientists, however if you want to claim that a failure to reject the null hypothesis is of any interest, you need to show that the statistical power of the test is sufficiently high that the failure to reject a false null hypotheis would be unusual were it false. You have so far failed to do so. So I ask again, what is the statistical power of the test? I will discuss your third hypothesis on the new blog article, as dana requests, you can find my post here.
  12. Dikran Marsupial at 14:47 PM on 14 October 2011
    Continued Lower Atmosphere Warming
    Prof. Pielke Your third hypothesis is that "the trends during this time period [2002-present] are different than the trends earlier in the time period." My question is: Is the difference in the trend prior to 2002 and post-2002 statistically significant at the usual 95% level of significance?
  13. The Earth continues to build up heat
    Several comments about the graph supplied by Albatross from RC. It would be interesting to know the basis of how the 7000-2000 data was estimated pre-Argo Looking at when the 700 & 2000 lines diverge around 2003, really this is when the Argo data started to become available. So this may be simply joining to disparate data sets together. But the really interesting period is 2007-2010. That divergence looks real. And during a Solar minimum at that. And that huge climb around 2000-2001! Could that be the energy transferred during the 1998 El Nino supressed the value a year or so earlier then it recovered? We really, REALLY need to see a paper on this! I wonder how many skeptics will look on this as a very big nail in the coffin of the 'it hasn't warmed since 1998' meme?
  14. Continued Lower Atmosphere Warming
    The 'pick an arbitrary short period' game can be extended. Look at the following graph of UAH data. Shown are the long-term trend, plus four arbitrarily-chosen non-overlapping but contiguous subdivisions of the whole dataset. (I saw a great graph of this done for the entire GISS dataset once.) All the short trends are negative, yet how is it that the long-term trend is still rising? I note once more that we are above the long-term trend for UAH at present, and close to it on other measures. Why would we think global warming has stopped?
  15. Continued Lower Atmosphere Warming
    My point of view as a layman is that PielkeSr knows the whole science (-snip-). I enjoy the clarity that Dana and Albatross bring to this. (-snip-).
    Response:

    [DB) Presumptions of malfeasance snipped.  Please allow these discussion threads to run their course before formulating conclusions.

  16. Greenland ice loss continues to accelerate
    Been looking at the artic ice volume as reported by the Polar Science Center. Extrapolating their data suggests that the artic may be ice free in summer time around 2020. If that happens, what will be the estimated effect on Greenland ice loss?
  17. There is no consensus
    Johathon, "climate sensitivity" = short-term transient sensitivity = fast feedbacks = 3 deg C The 6 deg C figure you keep providing is for long-term sensitivity / slow feedbacks.
  18. There is no consensus
    Jonathon, two very simple questions. If the range of plausible climate sensitivty values is 1.5C to 5C per doubling CO2, is there a consensus that the climate warms with added CO2? Yes or no? If the range of plausible values for the Hubble Constant is 55-80km/s/Mpc, is there a consensus that the Universe is expanding? Yes or no?
  19. Continued Lower Atmosphere Warming
    To follow on Albatross above and illustrate the 'pick an arbitrary short period' game, here is the requested 2002-present: And here is 1990-1997: And here is mid 1982-mid 1987: Yes, there are short periods where temperatures flatten. But these are present throughout the satellite temperature record. It would be nonsensical to draw any conclusion from these arbitrarily chosen lulls, because the trend continues to be up. BTW, here is 2006-present: So if one wants to take some meaning from short periods, one must also conclude that the most recent period indicates warming has not stopped.
  20. There is no consensus
    Scaddenp, (-Snip-). The Hansen value can be found here among other places: http://www.skepticalscience.com/Climate-emergency-time-to-slam-on-the-brakes.html Muon, We are discussing the range, not a value.
    Response:

    [DB] Inflammatory snipped.

  21. Continued Lower Atmosphere Warming
    Dr. Pielke on another thread here at SkS: "Policymakers, in my view, are being misled into believing that the climate should more-or-less monotonically warm when in reality both natural variability and the diversity of human climate forcings makes the issue of climate system heat content much more complex." With all respect to Dr. Pielke, that is his opinion, but the facts show that he has it backwards. He is also making an unsubstantiated assertion with regards to policy makers being "mislead". Dr. Mojib Latif and other IPCC scientists are aware that the warming will not be monotonic and have in fact cautioned that it will not be, it is actually the "skeptics" who seem to think so. I say that because it is in fact those who deny the theory of AGW and "skeptics" (even some "skeptic" scientists who know, or should know, better) who get excited every time there is a short-term slowdown or cooling (perceived or real). It is for that very reason that science sites like SkepticalScience (and OpenMind) have had to spend a lot of time refuting claims that global warming stopped in 1998 and 2002 etc. (the number of choices to cherry pick increases as the window is shortened). See here, here, here, and here. There are more, but I think you get the point. The scientific literature abounds with papers speaking to the variability of global temperatures and SSTs (some examples here and here). Unfortunately, because the global temperature records are inherently noisy (because if internal climate variability, such as El Nino and La Nina), "skeptics" can continue playing this deceptive game (and it is a game for some) of cherry picking statistically insignificant short-term "cooling" trends all the while the statistically significant long-term trend is UP. To do so is in fact misleading policy makers and confusing the public.
  22. Pielke Sr. and SkS Disagreements and Open Questions
    Dr Pielke @107, you say "global warming has flattened". When it is said that a long term trend has "ceased" of "flattened", what is being claimed is that future temperatures are more likely to lie close to current temperatures rather than close to the projection of the long term trend. Is this what you are claiming? More specifically, are you claiming that the RSS MSU Channel TLT anomaly relative to the 1979-1998 mean is more likely to be closer to 0.25 degrees K, or 0.4 degrees K (ie, approximately current values plus the 1 decade trend)? (RSS TLT anomaly as reproduced by Dr Pielke, Sept 7th, 2011). As an aside, I to believe that policy makers are being misled "into believing that the climate should more-or-less monotonically warm". However, that misleading is coming from people like your friends Christopher Monckton and Anthony Watts.
  23. Continued Lower Atmosphere Warming
    As part of a science project, a 5th grader plots the temperature for the Spring. April 2 has a record high in Boston--95 degrees Fahrenheit. The next seven days show an unusually low average of 60 degrees Fahrenheit. Clearly, based on this trend, Boston is not warming up that year, and spring is not coming. A baseball player starts off the season batting a poor 200. During the playoffs, however, he catches fire, batting over 400 for 15 games. The last game shows no exception: he starts off with a triple, then hits a home run. However, at his next two at bats, he strikes out and then grounds out. A commentator states that based on the last two at bats, the player is not improving at all, since his batting average is 0 percent. As silly as both arguments are, I don't see them as substantially different than arguing there has been no warming trend since 13 years ago. Some aspects in climate science are very complex and hard to understand (such as the heat transfer in oceans, or the feedback in clouds); accurately identifying trend lines is not one of these areas.
  24. Pielke Sr. and SkS Warming Estimates
    I am very suspicious the "regional/local" effects line. No denying that these effects are what matter to us most, but are the local effects due to local causes? I would like some substantial scrutiny of this. The very appealing side of this narrative for Western nations. GHG emissions are global in effect. In this way, the historical emission from western nations can have negative climate effects not just for themselves, but also on vulnerable nations with very low emissions. This creates complex questions over rights and responsibility that pure free-market only advocates struggle to solve. On the other hand, if you can suggest that local/regional land use change are main or even substantial driver for climate change in the same local region, then there is excuse to simply blame say Pakistan for its own climate problems and sit on your hands when it come to reducing emissions. Very appealing idea but I rather doubt that it is strongly scientifically based.
  25. Pielke Sr. and SkS Disagreements and Open Questions
    Let's please move any discussion of TLT trends to the new blog post on the subject, and move on to the discussion of OHC data here.
  26. Every Picture Tells A Story
    Very informative - as is the well selected reading list.
  27. Pielke Sr. and SkS Disagreements and Open Questions
    muoncounter - I took 2002 because visibly there appears to be a change in slope. I request you plot that as well.
  28. Pielke Sr. and SkS Disagreements and Open Questions
    Dikran Marsupial - I had three hypotheses. I request you complete the test and see what you obtain. It is a starting point for our further discussuions.
  29. Pielke Sr. and SkS Disagreements and Open Questions
    Tristan - You asked "Dr Pielke, [many policy makers] believe that the flat temperatures between 1998 and 2011 are a result of a cessation of anthropogenic warming, [will you acknowledge] that that flatness is [a temporary result] of natural variability[...]? " There is no question that the diversity of human climate forcings, including that from added CO2, has continued even as global warming has flattened. However, this behavior of the climate system illustrates our still incomplete knowledge of the climate. Policymakers, in my view, are being misled into believing that the climate should more-or-less monotonically warm when in reality both natural variability and the diversity of human climate forcings makes the issue of climate system heat content much more complex.
  30. Pielke Sr. and SkS Warming Estimates
    > the regional/local scale that matters much more to > society and the environment. On the regional/local scale, absorbign damages are of different kinds in different locations, you can absorb a whole lot of losses. That works for a while -- while the trading/transportation/financial system holds up, because each area can buy what it can't produce and sell what it overproduces. That's the definition of overshoot, ecologically. http://www.google.com/search?q=catton+overshoot It's not a solution. It's a way of postponing and increasing the damage while hoping the problem doesn't keep adding up. Remember the advertising slogan "The solution to pollution is dilution!" from the 1950s? Because impacts could be avoided. For decades.
  31. Michael Hauber at 10:40 AM on 14 October 2011
    The Earth continues to build up heat
    An interesting chart. Enso does act to move heat between the surface and the subsurface, with El Ninos moving heat from subsurface to the surface, and vice versa for La Nina. However most of this effect seems to happen above 700 metres if you track the detailed evolution of ENSO events, but possibly the effect extends deeper down in a more subtle manner. On this basis the strong La Nina period of the early to mid 70s increased heat content in 700-2000. Then between 1980 and 1998 a strongly El Nino dominated period resulted in a loss of heat which was a little more than enough to offset the heat that global warming put into this layer. Then since 1999 a more La Nina dominated period combined with global warming resulted in a rapid rise of 700-2000 metre heat content. Although squinting at the colours with my partially colour blind eyes, it looks like the strongest heat gain is in the Atlantic? Whereas if ENSO was driving the multi-decadal variation I'd expect it to be strongest in Pacific.
  32. Over 31,000 scientists signed the OISM Petition Project
    Tristan @10, the petition was originally circulated to "virtually every scientist in every field" in the US according to one of its critics. But the OISM refuses to indicate the size of the mailout. From SourceWatch:
    "OISM has refused to release info on the number of mailings it made. From comments in Nature:
    "Virtually every scientist in every field got it," says Robert Park, a professor of physics at the University of Maryland at College Park and spokesman for the American Physical Society. "That's a big mailing." According to the National Science Foundation, there are more than half a million science or engineering PhDs in the United States, and ten million individuals with first degrees in science or engineering. Arthur Robinson, president of the Oregon Institute of Science and Medicine, the small, privately funded institute that circulated the petition, declines to say how many copies were sent out. "We're not willing to have our opponents attack us with that number, and say that the rest of the recipients are against us," he says, adding that the response was "outstanding" for a direct mail shot. [16]"
    The original mail out only garnered about 15,000 responses. Despite Robinson's claims, without a precise statement of the mail out number, no significance can be assigned to the petition as a survey of scientific opinion. What is more, given the anecdotal evidence of the size of the mailout, and the small size of the respondents (15,000) compared to the number of "virtually every scientist in every field", the reasonable conclusion is that the response rate was very small. Indeed, if it were not, you can be sure that the OISM would be trumpeting not only the absolute number of signatories, but the response rate as well. Since the original mail out, the petition has been available online to add the signature, and has been frequently trumpeted by various political figures, so its presence has been known. Given that, the response rate is best given by the number of signatories divided by the number of potential signatories as given in the main article, ie, 0.3%. As such, this petition is no more significant than any of the various creationist petitions that get circulated. Indeed, given the close ties of the OISM and the Discovery Institute (an Intelligent Design creationist site), it can be viewed as one of the various petitions circulated by creationists.
  33. Every Picture Tells A Story
    Anyone care to draw a line of best fit through the Annual Mean NH Snowfall Extent of Fig 3 ?
    Response:

    [DB] The seasonal graphs have trend lines already in place, here.

  34. The Deep Ocean Warms When Global Surface Temperatures Stall
    Thanks Pete. And this is from the NODC data? Interesting how it can change so quickly, almost as if someone has flipped a lever and heat is now tracking down deeper. Just been reading Sutton & Roemmich (2011). Although I don't cover it in the post, most of the heat funneled down to the depths in the climate model used by Meehl (2011), occurs in the Southern Ocean (figure 4 in the post). That's what Sutton & Roemmich find looking at the WOCE (World Ocean Circulation Experiment) and ARGO data. The "missing heat" is running out of places to hide.
  35. There is no consensus
    Continued sensitivity discussion is better suited to the existing sensitivity thread. The consensus there is 3.5 deg C per doubling.
  36. There is no consensus
    Jonathon, I am curious. What is your reference for Hansen believing sensitivity to be 6? Wasnt what he said in public meeting I attended. Also, in consensus. Am I correct in assuming that in your mind, if there is a published value outside a consensus range, even in a refuted paper, then consensus doesn't exist?
  37. Pielke Sr. and SkS Disagreements and Open Questions
    pielkesr#103: ""The lower tropospheric global annual average temperature trend (TLT) from 2002 until now cannot distinguished from a zero trend."" The rationale for choosing 2002 as a breakpoint is still unclear. However, if you take what appears to be a natural breakpoint (1998), you see something completely different. Here is UAH from start to the beginning of 1998 with a 6 month running mean. The trend line is shown. Here is UAH from mid-1998 to present, same mean; the trendline has a higher slope than does the prior period. I seem to recall a video interview with Dr. Pachauri in which he clearly stated that warming was not expected to be monotonic (can't find the link to it at the moment). Perhaps the nonlinearity in the system that everyone agrees is present is expressed in these temporary flattenings along the overall rising curve. In view of that characteristic of these data, choosing arbitrarily short periods for analysis seems utterly counterproductive. And given the data have a high frequency noise, short periods are likely to be more contaminated -- and therefore misleading -- than long periods.
  38. Book review: The Inquisition of Climate Science
    1. Here's a sourcewatch wiki on Koch Industries, with references. Readers can do their own explorations from that starting point. You should add no. 3, Sasquatch, if you want to provide complete coverage: "Where does the industrial funding money come from?" Remember, the government isn't the only economic entity that engages in taxation (it's just the only one that offers representation (such as it has become)).
  39. Over 31,000 scientists signed the OISM Petition Project
    An intermediate argument at the level of most intermediate articles on SkS would be pointless. All that needs to be stated is the obvious: 1. Those who hold science degrees (and in particular undergraduate degrees only) are probably clueless in many areas of science. 2. What is the basis of the signers' expertise? 3a. If 32,000 is impressive, and I find 32,000 people who think you should die, will you kill yourself? 3b. If I find 32,000 atheists who say you should worship the Flying Spaghetti Monster (praise its name), will you? 3c. If I find 32,000 science majors who think the Earth is 6000 years old, will you then believe the Earth is 6000 years old? 3d. If I find 32,000 English majors who say that Joyce's Ulysses is the greatest work of fiction in English, does that settle the matter? 3e. (etc. ad nauseum) 4. If I create a petition that says the opposite, and I get 32,001 signatures from science majors, are you forced to believe my petitioned claim? 5. What happens if all of these 32,000 change their minds? Does your mind change as well? What if these 32,000 are then replaced in a new petition by a different set of 32,000? Will you short-circuit? 6. If 32,000 climate scientists put their expertise up against that of 32,000 science majors, who would be right about issues within climate science? Here you see that the maximum number is important. If I ask, "If 100 of the most-published climate scientists put their expertise up against that of 32,000 climate scientists, who would be right about issues within climate science?" then the denominator is critical, because I could bring it down to 1 vs. 32,000. It's all goofiness designed to prey upon people who, again, do not have the time, means, energy, training, and/or motivation to come to an understanding for themselves--or designed to confirm what we already suspected, the Great GW Hoax!
  40. Dikran Marsupial at 06:06 AM on 14 October 2011
    Pielke Sr. and SkS Disagreements and Open Questions
    pielkesr The hypothesis that "The lower tropospheric global annual average temperature trend (TLT) from 2002 until now cannot distinguished from a zero trend." is not a particularly interesting hypothesis for the simple reason that the statistical power of the test of a non-zero trend is very low because the timespan over which the trend is computed is too short. Your hypothesis is effectively the null hypothesis for the usual test for a non-zero trend. The statistical power is the probability that the null hypothesis will be rejected when it is false so if the test has little statistical power, we should not expect to be able to distinguish from a zero trend, even if the underlying trend is the same as the long term trend and global warming has continued unabated, but its effects are being masked by noise (i.e. internal climate variability, e.g. ENSO). Now if you want to suggest there is any scientific interest in this hypothesis, then you need to show that the hypothesis test has meaningful power. So my question is, what is the statistical power of the test?
  41. Book review: The Inquisition of Climate Science
    1. From where do the figures on funding from industrial sources come from? 2. How much money has been spent on supporting AGW research, and where does it come from?
  42. Pielke Sr. and SkS Disagreements and Open Questions
    Dikran Marsupial -Regarding "But heat going into the deep oceans doesn't impact surface temperatures or the ratio of TLT to surface temperatures" if the surface temperature trends are being used as quantifying the magnitude of global warming (and the so-called "clmiate sensitivity"), heat in the deeper ocean is not included in such an assessment. If the heat were at the surface, it would be seen in the temperature trend.
  43. There is no consensus
    Dikran, I am not missing the point. I never said that there is a consensus on the exact value, so you can stop repeating yourself on this issue. I have yet to see anything that support a consensus on the range of plausible values, and highly doubt that one exists. Typically the evidence against a consensus is to present data which does not conform, which I have already done. The Pagani estimates are estimates of the value, not a bound. The uncertainties listed after each value are his calculated range. Clear? Philippe, When assembling a range of value such as this, each individual measurement is assigned the same probability, assuming they were determined independently, just like rolling the dice. If additional research yields values which begin to cluster around a specific range, then we can assign higher probability to those values. In the case of climate sensitivity, we see values clustered not around a mid-range value, but at the high and low ends, but still yielding a similar mid-range value. This anti-Gaussian distribution would indicate that the mid-range value is less likely than either end.
  44. There is no consensus
    Jonathon - Looking at the Pagani paper, they are estimating equilibrium sensitivity, not transient sensitivity (the number usually listed as ~3°C/doubling of CO2.). Hansen estimated equilibrium sensitivity at ~6°C? So while the Pagani numbers are rather higher, they are really not directly relevant to the short term transient sensitivity of 3°C. Also, keep in mind that the high end of the sensitivity tail is much less determined than the low end. --- This is all smoke and mirrors on your part anyway, Jonathon. The consensus on values and ranges come from the evidence - if you wish to assert a climate sensitivity outside that range, present some evidence, not a petition.
  45. Pielke Sr. and SkS Disagreements and Open Questions
    Dikran Marsupial - Regarding "What exactly is the hypothesis that you seek to support using the post-1998 trends?" I suggest that the hypothesis be that "The lower tropospheric global annual average temperature trend (TLT) from 2002 until now cannot distinguished from a zero trend." using data from http://www.ssmi.com/msu/msu_data_description.html Also, "The lower stratospheric (TLS) global annual average temperature trend from 2002 until now cannot distinguished from a zero trend." and the trends during this time period are different than the trends earlier in the time period. I will be interested in what you conclude.
  46. Philippe Chantreau at 05:45 AM on 14 October 2011
    There is no consensus
    Jonathon, you're treating the extremes of the possible range as if they were equally probable as the mid range values. I doubt it is the case. The Pagani numbers should certainly give us cause for great concern.
  47. Dikran Marsupial at 05:45 AM on 14 October 2011
    There is no consensus
    Jonathon, you appear to be missing the point. Nobody is claiming there is consensus on the exact value of climate sensitivity. There is however consensus on the range of values that would be plausible. If you want to claim that the scientists don't agree on the range of plausible values then please provide some evidence to support that assertion. Your comment on the Pagani estimate(s) still doesn't clarify whether it is a bound or an estimate of the most likely value.
  48. There is no consensus
    Dikran, I guess it comes down to what we understand to be the range of plausible values, and if that range is sufficient to state that there exists a consensus. I am not comfortable making that claim at this time, as I would prefer to see a narrower range of plausible values before making that assertion. Also, I do not believe that scientists would agree on the range. This does not mean that a consensus could not be formed in the future. I do not need to know the exact value, but the concept that the high end of the range is a factor of three higher than the low end implies that we still have a long way to go. Given the EPA range of atmospheric CO2 to lie between 535 and 983 by 2100, the resultant temperature increase lies in the range is 0.5 - 7.0 C (low-low to high-high). The pagani value was a calculated number for three different times in the recent geological past: 7.1 +/- 1.0, 8.7 +/- 1.3, and 9.6 +/- 1.4 C/doubling. http://earth.geology.yale.edu/~mp364/data/2009%20Pagani%20et%20al.pdf
  49. Philippe Chantreau at 05:34 AM on 14 October 2011
    Pielke Sr. and SkS Disagreements and Open Questions
    Doesn't the 700m mark have to do with limitations of the earlier Argo network?
  50. Philippe Chantreau at 05:31 AM on 14 October 2011
    Over 31,000 scientists signed the OISM Petition Project
    Of all the nonsense spewed by deniers, this one is certainly one of the most ridiculous. The self contradictory arguments go like this: "There is no scientific consensus." Since it's quite easy to show that, in fact, there is one, this is often followed by "science is not done by consensus" with all manners of misundertanding what scientific consensus actually is. Attempts to correct the misunderstanding by pointing that consensus follows from the science instead of preceding it usually falls on deaf ears. This in turn, is often followed by arguments like the stupid petition thing, portraying a consensus of opinion among non experts as a valid one, right after insisting that consensus among experts is not. When emotionally charged, ideology driven opinion puts up its defenses, there is no amount of rational thinking that can tear them down.

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