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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 58801 to 58850:

  1. IPCC graph showing accelerating trends is misleading
    Helena I didn't follow the discussion but at a cursory reading of your claim I find it like a world upside down. You start at an early time and go forward while the IPCC goes the other way around. Are you surprised that you get different or even opposite results? The problem is the meaning and that's what (it seems to me) your're missing.
  2. IPCC graph showing accelerating trends is misleading
    (therefore your trends don't indicate anything for the behavior of temperature, as i said)
  3. IPCC graph showing accelerating trends is misleading
    Well, first the trends you calculated are NOT the ones shown on the IPCC. Second, you can easily imagine a temperature record with, as shown by IPCC, a greater slope for shorter periods indicating accelerated warming but where the temperature is in fact cooling.
  4. IPCC graph showing accelerating trends is misleading
    Eric most of what you say is out of topic we're not discussing natural or man-made acceleration here. We're just discussing the IPCC graph and their use of trends as an indicator of accelerated warming or to support their specific statement.
    Moderator Response:

    [DB] Actually, most of what Eric has stated is on-topic and germane to this discussion. You are tortuously arguing against a very simple point:

    "Note that for shorter recent periods, the slope is greater, indicating accelerated warming."

    Using Woodfortrees, this is easily seen, thusly:

    [Source]

    Or just the trends themselves:

    [Source]

    Where is the disagreement from the statement to the graphics? It really is that simple.

  5. Eric (skeptic) at 22:46 PM on 13 May 2012
    IPCC graph showing accelerating trends is misleading
    "concave up would be correct. Nobody is saying it didn't warm here." Helena, your phrasing is regrettably imprecise. Muoncounter pointed out that the warming is accelerating by a concave graph. "You can easily imagine records where linear trend fits to the last 25, 50, 100 and 150 years (and even 75 :) ) increase but where the is no warming." Again the issue is acceleration of warming, not simply "warming". The IPCC caption is
    "...Linear trend fits to the last 25 (yellow), 50 (orange), 100 (purple) and 150 years (red) are shown, and correspond to 1981 to 2005, 1956 to 2005, 1906 to 2005, and 1856 to 2005, respectively. Note that for shorter recent periods, the slope is greater, indicating accelerated warming".
    The IPCC graphic is overly simplistic (IMO) since it does not discuss the extent of natural acceleration and deceleration that could lead to a superimposed natural and manmade acceleration. That would require a paper. But the IPCC claim is that there is acceleration of warming (unattributed) and that the acceleration is current (as of 2005).
  6. Arctic Winter Analysis
    Thanks for the interesting article.It'll take a few reads to absorb. A question in the meantime - how do scientists get the sea level pressure and the surface air temperature measurements for a place like the Artic?
  7. Turbines in Texas mix up nighttime heat
    Michael, one could say, why not add in the rotational velocity of the Earth as well? Or is air in a plane hotter after take-off? KE for this purpose would be calculated with mean square velocity - ie square of deviations about the fluid mean velocity. Otherwise it depends on frame of reference. Definition of temperature requires local thermodynamic equilibrium in a volume. That volume would have to be moving with the fluid. If there is flow through the volume, then there is advection - no equilibrium. I don't believe the generator exports 59% of the wind energy - that's a very theoretical max. Riccardo, I agree that the 40% refers to emerging KE. My point is that it's no longer avial flow - it's azimuthal or turbulent eddies, and it can't go anywhere much. When it decays, as it must, it will be converted to heat. But MS's calc says it won't raise the temperature much.
  8. Glenn Tamblyn at 20:25 PM on 13 May 2012
    Two Centuries of Climate Science: part three - Manabe to the present day, 1966-2012
    LT @3. I love the image that in 'skepticland' they get confused easily. "It would be more accurate to say that greater CO2 concentrations cause the outgoing energy to meet greater resistance as it passes from the surface to outer space." My understanding of ther GH Effect is that most 'outgoing radiation' from the surface gets absorbed - perhaps 99%. What matters far more is how much of this initially absorbed radiation 'eventually' manages to escape. The GH effect is defined, less by how much is initially absorbed, rather than by how much is subsequently re-radiated. It is increased restriction of the re-radiated component that is the main game.
  9. michael sweet at 19:25 PM on 13 May 2012
    Two Centuries of Climate Science: part three - Manabe to the present day, 1966-2012
    Lazyteenager, You are incorrect. The energy into the Earth system currently does not equal the energy out. The Earth has an energy imbalance caused by human greenhouse gasses. See this post for evidence of ocean heat uptake. Energy in equals energy out at equilibrium. The equilibrium has been upset and the globe must warm to re-establish the equilibrium.
  10. IPCC graph showing accelerating trends is misleading
    Sphaerica27 : It's really a pain to understand what you're looking for. Everything is done on woodfortrees with HadCRUT3 variance adjusted global mean. First my homework : what i showed, responding to Tom's challenge : "it is not possible to pick arbitrary end points mimicking the IPCC graph, and to show a deceleration over the temperature record as a result. You have no counter example to the IPCC's procedure. " is that there exist a common start point for which it works : 1910-1934 > 1910-1959 > 1910-2009 gives a decreasing trend as you get closer to present : 25yr trend #Selected data from 1910 #Selected data up to 1934 #Least squares trend line; slope = 0.013717 per year 50yr trend #Selected data from 1910 #Selected data up to 1959 #Least squares trend line; slope = 0.00773312 per year 100yr trend #Selected data from 1910 #Selected data up to 2009 #Least squares trend line; slope = 0.00742333 per year The closer you get to present, the smaller the trend. Uhhhhhhhhhh Back to IPCC graph. The second thing i showed it that the not depicted 75yr period 1931-2005 is > the 100yr period 1906-2005, which goes against the increasing trend assertion by the IPCC. 100yr #Selected data from 1906 #Selected data up to 2005 #Least squares trend line; slope = 0.00724928 per year 75yr #Selected data from 1931 #Selected data up to 2005 #Least squares trend line; slope = 0.00659195 per year 50yr #Selected data from 1956 #Selected data up to 2005 #Least squares trend line; slope = 0.0124017 per year muoncounter26 : concave up would be correct. Nobody is saying it didn't warm here. Had it been the statement written in the IPCC, i wouldn't be here discussing it with you. The problem is the IPCC saying that linear trend fits to the last 25, 50, 100 and 150 years indicate warming. You can easily imagine records where linear trend fits to the last 25, 50, 100 and 150 years (and even 75 :) ) increase but where the is no warming. I really don't understand how you guys can defend the idea that the IPCC trend graph & statement support or indicate anything. "Do we really need trends to see what's been happening?" I agree with that. But you should tell that to IPCC. I'm the one criticizing their (mis)use of trends to support a statement.
  11. Two Centuries of Climate Science: part three - Manabe to the present day, 1966-2012
    re - #3, a certain amount of IR emitted by the planet's surface does not get back out into space because it is absorbed by the GHGs and re-radiated in all directions, including back towards the surface. To me, that's 'prevented' although some might prefer 'inhibited' I guess. Surely if energy in = energy out the lack of net gain would keep us as a snowball, given our distance from the sun - exactly the problem that got Fourier's interest going back in the early 1800s.
  12. LazyTeenager at 16:38 PM on 13 May 2012
    Two Centuries of Climate Science: part three - Manabe to the present day, 1966-2012
    The fact that carbon dioxide is a 'greenhouse gas' - a gas that prevents a certain amount of heat radiation escaping back to space --------- This is wrong. I know what you intended to mean, but in climate skeptic land they get confused easily. They do crazy things like picking at some analogy or metaphor in the belief that exposing the limitations of a metaphor somehow disproves the greenhouse effect. In case it's not clear the energy in must equal the energy out. This energy is in the form of radiation. It's not prevented from escaping back to space. It would be more accurate to say that greater CO2 concentrations cause the outgoing energy to meet greater resistance as it passes from the surface to outer space.
  13. Bob Lacatena at 14:48 PM on 13 May 2012
    IPCC graph showing accelerating trends is misleading
    Helena, I did look at your links and graphs, and what I'm saying is that they don't show what you claim they show. Let's try it this way... list the ranges of years, and the slope. Just do that. Let's see you cherry pick the years to make this work.
  14. IPCC graph showing accelerating trends is misleading
    Helena#21: "Increasing trends don't (-snip-) an accelerated warming, and decreasing trends ... a decelerated warming. They don't (-snip-) anything." That has to be a new highpoint in doublespeak. Changing trends don't indicate anything? That requires that 'there's been no warming since xxxx' doesn't indicate anything; nor is there anything indicated by 'there is no scientific basis for saying that warming hasn't stopped'. I suppose 'concave up' doesn't mean anything either. Do we really need trends to see what's been happening?
  15. Eric (skeptic) at 11:20 AM on 13 May 2012
    IPCC graph showing accelerating trends is misleading
    Obviously your post is staying since it got fixed. I disagree with your assessment of the log of the exponential and it is addressed here
  16. IPCC graph showing accelerating trends is misleading
    In my message 21 "(-snip-)" = "indicate" Sorry for the all caps.
  17. IPCC graph showing accelerating trends is misleading
    Eric : We'll see, if it disappears again i'll get rid of the all caps for the word "indicate". My all caps is Tom's bold (dunnow how to get my text in bold here). Anyway, on your message 20, here we are merely discussing communication skills and scientific rigor, not the reality of warming. Anyone who looks at the temperature trend see that it is warming. I've read KR response on the other thread about linear increase or acceleration in temperature trend and exponential CO2. What he says is not entirely correct, the exponential of the CO2 is taken care of by the log of forcings, it doesnt really play there (the exponential, not the CO2 !). What matters (in a simplified version) is the relaxation time. That tells you whether the response will be linear or quadratic. But it's out of topic here. Anyway, i'll just wait a few mins see if my post stays, then gotta go. Thanks for the discussion. Cheers
  18. Eric (skeptic) at 11:01 AM on 13 May 2012
    IPCC graph showing accelerating trends is misleading
    Perhaps it was your use of all-caps (tat is forbidden)
  19. IPCC graph showing accelerating trends is misleading
    Sphaerica @18 What are you talking about ? I did provide graphs (cf previous posts) Tom @19 1/ As i said, that merely shows that uncertainties on the trends are quite large. 2/ So you do agree with me that the 75yr trend goes against the picture presented of increasing trends, right ? You said yourself : "It is not necessary that the error bars be miniscule for the purported IPCC claim to be correct. It is only necessary that the measured trend be greater." Therefore, according to your own standards, i did show that the measured trend for the 75yr trend was not greater, and that had the IPCC been consistent and depicted all 25yr periods without leaving out the 75yr trend (cherrypicking ?), the IPCC assertion would not have been possible. According to my standards, all i am doing here is pointless because, as i said, comparing trends of different lengths is meaningless. You can find any result you are looking for. 3/ You challenged me by saying "it is not possible to pick arbitrary end points mimicking the IPCC graph, and to show a deceleration over the temperature record as a result. You have no counter example to the IPCC's procedure. " I found the counterexample with an arbitrary starting point (1910) and decreasing trends mimicking the IPCC graph (25, 50, 100yr trends). Again, according to your own standard and following IPCC procedure where, as you say yourself "it is only necessary that the measured trend be greater", i've succeeded. Now that you have it you seem unhappy that it exists. "The reason is that you are, fairly obviously, cherry picking artifacts of noise in an accelerating temperature trend. " Of course I am cherry picking the starting point ! You challenged me by saying that i wouldn't be able to find an arbitrary point and mimick the IPCC procedure with decelerated trends. So i looked for it and found it. Now let's get back to what it all means : what the ipcc says is that their increasing trends (-snip-) accelerated warming. Clearly that statement is wrong. Increasing trends don't (-snip-) an accelerated warming, and decreasing trends (my example) don't (-snip-) a decelerated warming. They don't (-snip-) anything. I don't understand that you guys can defend such a graph. Isn't it easier to just admit that it was not the best chosen graph to depict that warming is accelerating ?
    Moderator Response:

    [DB] Please acquaint yourself with this site's Comments Policy (link next to every comment input box). It is noted that, more than anything, you are simply being argumentative for its own sake.

    Multiple usages of all-caps snipped.

  20. Eric (skeptic) at 10:55 AM on 13 May 2012
    IPCC graph showing accelerating trends is misleading
    In a previous thread about the graphic above, I basically agreed with KR"s conclusion here. I think the graphic shows a particular type of acceleration over the long term (century timescales). As I noted in that thread they left out the 75 and the 125 year trends which narrows their definition of acceleration and would add noise to the visual. The idea of noise from natural variation is an important part of the analysis of acceleration which this graphic does not attempt to provide.
  21. IPCC graph showing accelerating trends is misleading
    Helena @13: 1) Nobody who is arguing a case that depends critically on choosing just one of two available temperature indices should be talking about "arguing mere semantics". The Gistemp Land Ocean Temperature Index (LOTI) shows a trend of 0.0169576 C per year from 1981-2005, a trend of 0.0139565 C per year from 1917-1941, and a trend of 0.0134231 C per year from 1918-1942. For what it is worth, HadCRUT4 also shows a reduced trend over the 1910-1940 period, and an increased trend over the 1970-2010 interval, although obviously I do not have precise trends. 2) The 75 year trend is 0.00650795 C per year, compared to 0.00722857 C per year for the 100 year trend. The difference, less than 0.001 C per year is less than the difference in trend you dismiss as merely semantic when it suites you. It is certainly not enough to alter the visual impact of the graph, or to alter the conclusions of the IPCC. 3) The 50 year trend from 1910 is 0.00761979 C per year; the 100 year trend is 0.00749844 C per year. The difference is just over 0.0001 C per year. What was that you said about merely semantic differences again? More importantly, the pattern is not preserved in Gistemp, in which the 50 year trend is greater than the 100 year trend. Clearly, therefore, you do not have an example showing deceleration in which successive trends from the start point are less than each other by a large (although not quite statistically significant in one case) margin. The reason is that you are, fairly obviously, cherry picking artifacts of noise in an accelerating temperature trend.
  22. Bob Lacatena at 09:58 AM on 13 May 2012
    IPCC graph showing accelerating trends is misleading
    Helena, Nothing you are saying makes any sense... or bears out, when I look at the actual data. Up is up, no matter how you try to stand it. Please produce a graph (use woodfortrees.org if you like) that clearly proves your point. And try to do it without cherry picking end points and ranges.
  23. IPCC graph showing accelerating trends is misleading
    At the end of my first paragraph, replace "cooling" by "decelerating warming"
  24. IPCC graph showing accelerating trends is misleading
    dana @14 : don't you agree that my assertion stating that, over the 1910-2010 period, the decreasing slope for the linear trends of the first 25, 50 and the full 100years *indicates* cooling is untrue ? Well, in the same way, the assertion by the IPCC that the increasing slope for the linear trends over the last 25, 50, 100 and 150 years *indicates* accelerated warming is also untrue. Moreover, as shown above, the linear trend for the last 75 years goes in the wrong direction, so at the very least it should be considered as cherry picking the trend baseline to pick only the trends that agree with what you want to assert. This has nothing to do with climate science or denying that the world is warming (it is), it's just scientific rigor. Muoncounter @15 : Sorry but i am asking for qualitative reasons, not quantitative ones. "Short" and "long" are quantitative assessments : of course there are order of magnitudes of difference between the two timescales, but that's the whole point of my example. You cannot just say that because there are orders of magnitude of difference, the system has qualitatively a different behavior. Here is an analogy : From 101°C and orders of magnitude up, water is qualitatively the same : vapor. But from 99°C to 101°C, it is qualitatively different (phase transition) even though the temperature changes very little. The underlying question is : in a complex system, how do you know the timescale (if any) over which you can say that "internal variability" (to be defined) is filtered out. But that's out of topic here.
  25. Turbines in Texas mix up nighttime heat
    Betz's law says that the horizontal wind velocity can not be zero downwind and that there is a theoretical maximum efficiency of 60%; hence 40% of the "input" energy is still kinetic energy of the wind. If the real efficiency is for example 50%, i.e. it's electricity to be used elsewhere, the remaining 10% goes into heat due to electricity production losses, friction and viscosity due to the increased turbulence. The latter can then be just a few percent. Even that 10%, though, could be locally significant if sustained. But once it gets diluted by natural mixing over relatively large volumes I don't see how it could produce significant warming. I too think, with Nick, that we do not have a clear explanation of the tempemperature rise.
  26. Bob Lacatena at 06:10 AM on 13 May 2012
    Increasing CO2 has little to no effect
    photeki, Hint... anyone who includes lots of words and graphs and numbers, but no actual mathematics, is being lazy and trusting to common sense and "thought processes" to qualify everything while quantifying nothing. More directly... his perspective and opinions are totally worthless. Is it not peer-reviewed because he's afraid the process is flawed, or just because he's so demonstrably wrong? How often do people get to walk onto the floor of the U.S. Mint and demand their fair share of freshly printed bills, because the money-review system is flawed and unfair and they deserve more?
  27. IPCC graph showing accelerating trends is misleading
    Helena#13: "you cannot prove that the impossibility to go from hours to 25 years is qualitatively different than the one going from 25years to 150years. " Really? 150/25 = 6:1 25 years = 219150 hours. Your examples of comparing temperatures 12 hours apart to temperatures 25 years apart yields 219150/12 = 18262.5:1 Comparing temperatures (and temperature trends) over short time frames to long time frames is qualitatively different - and extremely misleading.
  28. IPCC graph showing accelerating trends is misleading
    Helena, you seem to miss the point of this post. All the IPCC is doing is saying that in recent years/decades, global warming has accelerated. That is true. It doesn't mean that there can't be prior years with similar warming trends to that in recent years. We have discussed the 1910-1940 warming here and here. There's certainly nothing "misleading" about the IPCC figure.
  29. IPCC graph showing accelerating trends is misleading
    True, that was a 26year period. So there is a 0.0017°C/year difference in the trend. Well i guess you're right if we stick to semantics, not to science rigor as the statement seems very much sensitive to error bars and to endpoints (ironically the statement would be wrong in AR5 as 1987-2011 is 0.0155809 per year). What about the 75yr trend i was talking about ? And the 1910 thing ? "Finally, with regard to your post 5, 12 hours is not a period long enough to represent a climatology." You know as much as i do that 30yrs it nothing more than a convention. Of course daily temperatures don't define a climatology, but 25year periods don't define one either (except by convention) and you cannot prove that the impossibility to go from hours to 25 years is qualitatively different than the one going from 25years to 150years. That's the whole point i'm making : having similar time periods is the minimum required (but not sufficient) when you compare trends !
  30. IPCC graph showing accelerating trends is misleading
    Helena @9, you are obviously grasping at straws. It is not necessary that the error bars be miniscule for the purported IPCC claim to be correct. It is only necessary that the measured trend be greater. And the last datum on the IPCC graph is 2006. However, having just checked FAQ 3.1, I notice the IPCC calculated trends terminate in 2005. So, comparing the 1981-2005 trend (0.0188397 C per year), to that for 1917-1941 (0.0171067 C per year) and 1918-1942 (0.0171202 C per year). The difference is approximately 0.002 C per year. (Please note that 1980-2005 is a 26 year period.) Finally, with regard to your post 5, 12 hours is not a period long enough to represent a climatology. Therefore your analogy is specious.
  31. IPCC graph showing accelerating trends is misleading
    Ouch still a zero missing, sorry
  32. IPCC graph showing accelerating trends is misleading
    I meant 0.02°C/decade (and 0.0002°C per year)
  33. IPCC graph showing accelerating trends is misleading
    Tom @ 8 Uhh i didn't know you could get the raw data, nice tool. Well, then i switched to to the 1917-1942 25yr-period. slope = 0.0178289 per year For the 1980 to 2005 period : slope = 0.0180092 per year And don't tell me error bars are smaller than 0.0002 °C/decade ! PS : How can the last point on the IPCC graph be 2006 as 2005 is not even depicted ?
  34. IPCC graph showing accelerating trends is misleading
    Helena @3, the trend for 1982-2006 (the last 25 years of the temperature record used by the IPCC) is 0.0202857 C per year. That from 1915-1940 is 0.014621 C per year, which is substantially less. That from 1980-2005 is 0.0180092 C per year. Of these three trends, that from 1915-1940 is lowest. That fact could easily have been checked by examining the raw data of your own plot. So, what you have shown is not that point number 2 is wrong, but merely that you are prepared to assert that it is without properly checking the data.
  35. IPCC graph showing accelerating trends is misleading
    To sum it up (sorry for the length of the links, i hope it's not considered as spamming) : - I did find a counterexemple, that is say if you start in 1910 you can find that the first 25yrs trend is higher than the first 50yrs trends which is also higher than the full 100yrs 1910-2010 trend. - The IPCC picture does not work if you take the 75yr trend (1930-2005) that they don't depict (they skip from the 50yrs to the 100yrs) : the 75yrs trend is smaller than the 100years trend. How is taking the 75yrs chery picking, as you are stating yourself that it is based on 25years intervals ? - But maybe you think 75yrs is cherry picked and the 25yrs of your 2nd point applies to any 25yr-period ? Then I also showed you that the past 25yrs (1980-2005) have been warming at the same rate as the 1915-1940 25yrs period.
  36. IPCC graph showing accelerating trends is misleading
    Ok here it works with a common starting point in 1910 link 1 By the way, isn't it weird that IPCC represents 25, 50, .., 100, and 150 ? They're missing 75 (and 125). Well, that's because with 75 (1930-2005), it doesn't work :). link 2
    Moderator Response: TC: Edited links to preserve page format.
  37. IPCC graph showing accelerating trends is misleading
    "More importantly, your argument entirely misses the more important point that Monckton completely misrepresents the nature of the IPCC's argument premised on the graph in question." And you miss the most important point that you cannot compare trends over different time periods. It's all i aimed to show (with wrong numbers possibly, but i gave you a simple counterexample with the midnight thing). Take for endpoint today at midnight, and you'll see that you have a cooling trend over the past 12h but a warming trend of the past 30years.
  38. Michael Whittemore at 02:45 AM on 13 May 2012
    IPCC graph showing accelerating trends is misleading
    This video at 6mins in shows Monckton explain that the climate system is like a sign wave and that the IPCC are drawing the trend lines on the up ward slop of this sign wave of climate change. He seems to be changing his angle of attack and trying to trick his audience into thinking that the reason he is right and the IPCC are wrong, is that we are going to see a cooling period.
  39. IPCC graph showing accelerating trends is misleading
    I hadn't done the precise graph. Before I answer on point 1, the tool you used allowed me show that point number 2 ""That the pace of warming over the last 25 years is greater than that in preceding years on the record."" is wrong : link
    Moderator Response: TC: Edited link to preserve page format.
  40. Increasing CO2 has little to no effect
    photeki @127, the linked article immediately demonstrates that Roy Clark is yet another in the long line of supposed "skeptics" who attempt to refute the theory of the greenhouse effect with out first bothering to learn what it is. Specifically, he attempts to show that the CO2 effect is saturated by discussing back radiation only. The greenhouse effect is not based on back radiation, and any discussion that assumes it is shows the author to be in complete ignorance of the theory they purport to refute. You will find a basic introduction to the greenhouse effect here. Read it carefully. Notice how the relevant factors are the Top of Atmosphere radiative balance, and that no mention of back radiation is needed. And for the record, if you work out the radiative physics for an increase of CO2 at the TOA, it does result in significant changes in radiative forcing, of 3.7 W/m^2 per doubling of CO2.
  41. IPCC graph showing accelerating trends is misleading
    Helena @1, we would be more impressed if you did not so obviously have to cherry pick your data points to reach your conclusion. If we in fact take the first 20 years of the HadCRUT3v temperature index, ie, from 1850 to 1870, the linear trend is 0.00238824 C per year. The trend for the first 40 years (1850-1890) is 0.00309971 C per year, showing an increase, not a decrease in the trend. The trend for the first 100 years is 0.00231824 C per year, barely lower than the trend for the first twenty years, and I doubt the difference is statistically significant. Finally, the trend for the first 150 years is 0.00369995 C per year, significantly greater than any of the other three trends examined. As the longest of the start year trends is also the largest trend of those examined, the series certainly does not show deceleration. Even if I plot from the cherry picked start point of 1860, except for 1860-1880, the later the end point of the trends examined, the larger the trend. Again this clearly does not show deceleration. What is more, even the 1860-1880 trend is inconsequential. The data for that period comes almost exclusively from Europe, the North Atlantic and the Eastern US. As such it represents a regional rather than a global temperature, and regional temperatures have larger trends than global temperatures. (Note I used the period 1860-1960 for the 100 year trend to keep the cherry picking to a minimum.) So, contrary to your apparent claim, it is not possible to pick arbitrary end points mimicking the IPCC graph, and to show a deceleration over the temperature record as a result. You have no counter example to the IPCC's procedure. More importantly, your argument entirely misses the more important point that Monckton completely misrepresents the nature of the IPCC's argument premised on the graph in question. Note: trends simply cut and paste from Wood for Trees, and the number of "significant figures" in no way represents a claim of statistical significance. Graph of the trends can be found here.
  42. Daniel Bailey at 01:42 AM on 13 May 2012
    Increasing CO2 has little to no effect
    As a newcomer, Welcome! Quite frankly, anyone who runs around claiming "fraud!" like Roy does is already 1 foot in wingnutville. Add to that the usual gibberish about "2nd Law" violations and he takes the next step all the way in. Also speaking frankly, your whole linked site is a Gish Gallop of epic proportions. If you would like to select the 1 specific item that you feel Roy's whole case rests upon, do so and someone here will engage you on that. On the appropriate thread. One way to best utilize this site is by looking at the argument structure via taxonomy: http://www.skepticalscience.com/argument.php?f=taxonomy Or you can just use the Search Function in the UL corner of every page. Just plug in a term like "2nd Law" and you'll get something like this. BTW, Roy is welcome to come here openly. We don't bite.
  43. IPCC graph showing accelerating trends is misleading
    I dont like Monckton, but he's right on that one .... Here are two assertions : Linear trend fits to the first 20 (1860-1880), 40 (1860-1900), 100 (1850-1950) and for the full 150 years (1860-2010)are shown. Note that for periods ending closer to us, the slope is smaller, indicating decelerated warming. The pace of warming over the full 150years (1860-2011) has been slower than during the first 20, 40, and 100 years of the instrumental record. Are those two assertions wrong ? If they are not, will we get a chance to read them in the next IPCC report ? And in the SPM which also had a sentence comparing the linear warming trend over the last 50 years with the linear trend for the last 100 years and did not put it in perspective with the first 20 years (for example). Of course you cannot compare trends on different time periods.... ! On any given day, the trend from midnight to midday is about 1°C/hour (+/-0.5), which far exceed any global warming trend over any time period you want [1]. I can give show you global cooling too if you want. [1] 1°C/hour = 87 600°C/decade "That the pace of warming over the last 25 years is greater than that in preceding years on the record." How does the trend of the last 25yrs compare with the trend between 1915 and 1940 ? (same 25yrs basis)
  44. Increasing CO2 has little to no effect
    Hello, I'm new to this place and don't really want to cause any fuss and this may have been covered elsewhere, however I am very interested in all of the topics covered so far. Not wanting to post a link to anything that may be biased whatever a persons personal belief is, I still believe scientific work deserves credit where it is due and discredit if it can be falsified. Please any input on the findings of Roy. Clark on the questioning of radiative forcing models and techniques would be much appreciated. http://venturaphotonics.com/GlobalWarming.html I realize he is very much what you would consider a skeptic but any confirmation of his observations and/or conclusions, contradictions, corrections would be handy. I am currently unaware if he has tried to submit this work for peer review as I doubt he believes the system is currently without faults or bias itself. Thanks
  45. New research from last week 18/2012
    Came across this http://www.irishtimes.com/newspaper/sciencetoday/2012/0510/1224315839757.html Genetically connecting widely separated Octopus populations with insight into the history of the Western Antartic Ice Shelf...
  46. Two Centuries of Climate Science: part three - Manabe to the present day, 1966-2012
    Thanks John for a concise and very readable series, and also to JG for the wonderful graphics. I've always wanted to find time to read Spencer Weart in full, but never succeeded. This summary is a big contribution.
  47. michael sweet at 23:07 PM on 12 May 2012
    Turbines in Texas mix up nighttime heat
    Nick, Please provide a reference that shows the wind speed is not part of the temperature. In the College chemistry textbook that I teach from, the temperature of a gas is proportional to its total kinetic energy. To me that would include the wind kinetic energy. I think you separating the wind speed from the temperature is incorrect. There is no energy liberated to convert into heat. Wind generators remove energy from the air. That cannot heat the air. A small fraction of the wind kinetic energy from the atmosphere is turned into heat which is returned to the atmosphere as molecular kinetic energy. In the absence of the generator friction would convert the wind into heat somewhere else when the wind dissipated. My calculation indicates that maximum temperature increase is 0.03C. I doubt real increase could be anywhere near 0.01C for the wind that goes through the generator (although I know little about turbulence), the rest is unaffected. Obviously most of the energy is not trapped or the wind farm would cause the wind to stop in its vicinity. The generator definitely exports 59% of the energy. The OP states that mixing of the atmosphere causes the temperature increase. Mixing can provide all the needed energy, converting wind into heat cannot.
  48. Turbines in Texas mix up nighttime heat
    Michael, Yes, I think your second calculation is more convincing. It does say that the temp rise would be less that what is observed. But I think my claim that the energy liberated would be comparable to the elec output is still OK. It sounds like a variant of the problem with the inversion layers. When the turbines are working, there's too much wind for the waste energy to create a temp rise. So for my part, I now don't know what could explain the temp rise.
  49. michael sweet at 21:51 PM on 12 May 2012
    Turbines in Texas mix up nighttime heat
    Nick, The temperature of the air is related to the square of its root mean square velocity which is 1150 miles/hr for nitrogen at 25C. The kinetic energy of the wind is related to the square of its speed which is say 30 mph on a windy day (the power in the wind is related to the cube of the speed). It seems to me that if all the energy in the wind was converted into heat it would not raise the kinetic energy of the molecules significantly. Possibly a calculation of the heat capacity of the air would be more useful. The specific heat of air is about 1.0 kj/kg. 1 kg of wind at 30 mph has about 80 joules of energy in it. That comes to about .08C increase in temp if 100% of the energy is converted into heat. That means a maximum of 0.03 C temp increase if the wind generator removes 59% the energy. In addition, a wind generator only converts the wind that passes over its blades into energy, since a much larger vertical slice of the atmosphere is moving, most of the energy stays as wind. Can you provide a calculation as to how much you think converting all the wind energy into heat would raise the temperature of the atmosphere? A peer-reviewed citation would be better. Wind generators remove energy from the local atmosphere. They do not provide any energy and cannot heat the atmosphere. The wind motion is part of the measure of temperature.
  50. Turbines in Texas mix up nighttime heat
    Or, I should say, 41:59.

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