Comments

1. #1 Crakar14

   December 9, 2008

   So what you are saying is 30 years of satellite data has now become invalid by simply tweaking a few lines of code to remove an error in the data processing and hey presto the sat data now matches with the model predictions.

   What i would like to see is a graph which compares the pre tweaked sat data, the model prediction data and the weather balloon data. To tweak sat data is one thing but to dispute the accuracy of a thermometer is another.

2. #2 coby

   December 9, 2008

   Sorry to burst your conspiracy theory bubble, Crakar, but those satellite studies you think are being falsified are produced by Spencer and Christy, two darlings of the denialist campaign.

   Check out all of the various temperature indicators here

3. #3 Crakar14

   December 10, 2008

   Conspiracy theory bubble?

   From your link”Based on data from Angell’s global network of 63 radiosonde stations, over the period from 1958 through 2005, the global mean, near-surface air temperature warmed by approximately 0.17�C/decade, the 850-300 mb tropospheric layer warmed by about 0.09�C/decade, the 300-100 mb tropopause layer temperature cooled by approximately -0.23�C/decade (driven mainly by large changes in the Polar zones), and the 100-50 mb low-stratospheric layer cooled by about -0.62�C/decade. At the surface, 2002 remained the warmest year in the 48-year record (0.88�C above the long-term mean), and 2005 was the second warmest year with a departure of 0.82�C”

   Dont see too much warming here do you?

4. #4 coby

   December 11, 2008

   Cooling above the troposphere is a predictable response to an enhanced greenhouse caused warming and this observation is more evidence against the other candidate causes out there, such as GCR or increased insolation.

   Now, why are you switching to radiosondes? I guess you have no response regarding Spencer and Christy’s satellite analysis…

5. #5 Crakar14

   December 11, 2008

   First of all if you are going to supply links to supporting evidence the evidence should be up to date not 3 years old. That aside i have switched to radiosondes as the debate has progressed. As you state the troposhpere should warm as per model predictions.However the sat data showed no warming so something was wrong.

   What i find funny about all of this is rather than doubt an as yet (due to sat data) unproven theory they went straight to the sat data and went searching for an error that may not have even existed. But low and behold they find one and after a tweak here and a tweak there hey presto the sat data now matches the theory.

   Of course there is the problem of that pesky radiosonde data that still shows no warming, oh i no we can just re jig the data on that as well.

   So in the end we had two independent sources of data that were considered accurate and therefore valid, until they both diverged (both showed cooling or no warming)
   from an unproven theory. Rather than treat these two independent sources of data as being accurate they simply tweaked the data to suit the theory. This is not science Coby.

6. #6 Mrs. W

   January 3, 2009

   Being that we live exclusively in the troposphere, that’s the layer I’m most concerned with.

7. #7 Mark

   February 15, 2009

   Am I wrong or does the linear regression of the data start a couple of years after the satellite data? If you started the regression at 1979 (particularly for the UAH data), it looks to me like the slope of the line would be almost flat (perhaps a slight increase). If you include the early data and update the data to 2008, what does it look like?

8. #8 R James

   July 10, 2009

   I’ve just plotted all the UAH data, including June 2009. Sorry, there’s no warming in the past few years. Certainly the last 7 years is cooling. Without doing the stats, it looks like about 0.2 degC warming over the past 30 years, and decreasing.

9. #9 coby

   July 10, 2009

   R James,

   The issue we are concerned about is change in climate. Climate is defined as roughly 30 yrs average weather. You can not make any conclusions about climate trends with anything less than 15 or 20 years, so observations over the last 7 or 10 or 11 are not enough.

   Please see this post:
   http://scienceblogs.com/illconsidered/2008/09/signal_vs_noise.php

10. #10 dhogaza

    July 10, 2009

    Without doing the stats

    you shouldn’t bother posting.

11. #11 R James

    July 10, 2009

    I agree, it’s accepted that climate trends need at least 30 years of data to be meaningful. How about 4,000 years. http://www.greenworldtrust.org.uk/Science/Images/Main/Warm_periods.jpg OOps – long term trend looks like cooling, and looks like the rise of the past 100 years is nothing unusual.

    I see that you don’t like satellite data, but I have a few concerns about surface data when I see that the magnitude of adjustments is about the same as the anomaly. http://www.strangerthanfiction.org/2009/07/10/rss-global-temperature-for-june-09-also-down/

12. #12 dhogaza

    July 10, 2009

    OOps – long term trend looks like cooling, and looks like the rise of the past 100 years is nothing unusual.

    How about the fact that you’re linking to an extremely stupid denialist site and that this graph is nothing at all like the long-term record accepted by science.

    I can make shit up too. Making shit up doesn’t prove science to be wrong.

    I see that you don’t like satellite data, but I have a few concerns about surface data when I see that the magnitude of adjustments is about the same as the anomaly.

    Oh, gosh, someone who doesn’t think that the raw satellite data needs to be adjusted, too …

    Regardless, your comment’s just another restatement of statistical illiteracy

13. #13 coby

    July 10, 2009

    R James,

    If you knew it takes 30+ years to talk about climate, why did you talk about 7?

    Thanks for one of the clearest examples of arguing out of both sides of your mouth. In one breath you switch from preferring a 7 year temperature record over a 150 year record to preferring a 4000 year record over a 150 year record. Any argument, as long as it supports you preferred conclusion.

14. #14 R James

    July 10, 2009

    Strange, I don’t recall saying that satellite data doesn’t need correction. I simply pointed out that surface temperature also requires correction. Actually, I find that there’s surprisingly good agreement between the two methods (although GISS struggles a bit to match the others).

    I can find lots of sources of longer term data, if the one I presented earlier doesn’t suit you. They all have one thing in common – there’s nothing unusual about current climate movement.

15. #15 dhogaza

    July 11, 2009

    They all have one thing in common – there’s nothing unusual about current climate movement.

    The only peer-reviewed, scientifically accepted reconstruction is Mann’s hockey stick which shows that the current climate movement is, indeed, unprecedented during the last couple of thousand years.

    And don’t give me that lying denialist crap about the hockey stick being debunked by a retired business man from the mining industry or a tv weather broadcaster who apparently never even got an undergraduate degree.

16. #16 Snowman

    July 11, 2009

    Dhogaza -

    Some of us would be interested in knowing exactly what aspects of Steve McIntyre’s deconstruction of the hockey stick you disagree with.

    I am sure you won’t simply take refuge in calling him a liar, a denier and fraud, but will be more specific in your objections. I am sure, too, that you won’t merely say that lots of people have carried out their own analyses and agree with the hockey stick – bearing in mind that it is part of Mr McIntyre’s case that these apparent validations repeat the original errors.

    Or course, you may think that he is wrong in making this claim. Even so, I am sure you will agree that you cannot justify a statistical procedure by pointing to other studies which are accused of making the same invalid assumptions. No, you must show where, precisely, the problem lies.

    Looking forward to reading your analysis.

17. #17 dhogaza

    July 11, 2009

    I am sure you won’t simply take refuge in calling him a liar, a denier and fraud

    The first two are true. The last, no, I don’t think he’s a fraud, so I won’t take refuge in calling him a fraud.

    I first ran across McIntyre when he was claiming that the NAS review of the original Mann hockey stick supported the “hockey stick debunkers”, when it’s clear that the report says the opposite. That makes McIntyre a liar.

    The denier bit is obvious.

18. #18 dhogaza

    July 11, 2009

    bearing in mind that it is part of Mr McIntyre’s case that these apparent validations repeat the original errors

    Uh, no, they don’t all repeat the original errors. You really gotta stop believing McIntyre.

    If he’s right, of course, then there really *is* a global conspiracy among climate scientists and climate science is a fraud. You may go on believing it if you wish.

19. #19 R James

    July 11, 2009

    It’s interesting that the IPCC discretely dropped the hockey stick from its 2007 report. Anyone glancing at it can see that it missed the little ice age etc. It just didn’t fit in with existing known trends.

20. #20 coby

    July 11, 2009

    Considering MBH98 is over 10 years old and there has been a great deal of new research in that area it is hardly surprising that it is no longer prominently featured. It is however still referenced and presented together with a multitude of other reconstructions (see Chapter 6 of AR4 (large PDF): http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Print_Ch06.pdf ).

    That would be fig 6.10 and it still looks like a hockey stick.

21. #21 dhogaza

    July 11, 2009

    It’s interesting that the IPCC discretely dropped the hockey stick from its 2007 report.

    Yes, that’s what happens when science is established, and scientists no longer feel the need to say “apples fall down, not up!”

    Love it, leave it, loath it, within science Mann’s work is now well-established.

    What denialists need to do is to establish their own answer to science – which of course, McIntyre and Watts etc are trying to do.

    Pity they’re restricting themselves to scientific results that happen to contradict their own political beliefs.

    You’d think that if they really believe BlogScience by non-scientists is superior to science done by professionals that they’d attack all of science, to make it clear that they’re really only interested in Truth and Beauty, not politics.

22. #22 Richard

    July 11, 2009

    Coby –

    “It” (the Hockey Stick) “is however still referenced and presented”. Yes it is and that is the shame of the IPCC that such a fraudulent piece of work is still there. It is the Hockey stick and the story behind it that first lead me to doubt the IPCC story on global warming. Gore’s lies and further research convinced me things dont quite add up.

    The Hockey Stick – temperatures remain dead steady almost for the last 1,000 years. Gone are the little Ice Ages and the Medieval Warm period. The little Ice Age the warmists say was a “local phenomenon”. It coincided with the Maunder minimum. The Sun of course is a global phenomenon. And the warmists want to discount the Sun’s influence. So local phenomenon? I dont think so!

    The Medieval warm period – did it exist – of course! Was it warmer than today – definitely! Was it a Global phenomenon? Yes! The people with the largest database on the subject:
    http://www.co2science.org/data/mwp/mwpp.php

    You claim it doesnt matter whether it was or not (warmer). Oh yes it does! The warm period happened without the help of Anthropogenic CO2. It would cast complete doubt on the AGW hypothesis – which depends heavily on the warming of the last 3 decades or so.

23. #23 Richard

    July 11, 2009

    Why fraudulent?

    1. The authors of the graph had used the varying widths of tree-rings as THEIR PRINCIPAL METHOD of estimating early-climate temperatures.
    2. THE IPCC HAD, prior to this, WARNED AGAINST USING TREE-RINGS AS PROXIES for pre-instrumental surface temperatures as they were prone to be inaccurate.
    3. They none-the-less used them and gave them 390 TIMES AS MUCH WEIGHT AS ANY OF THE OTHER DATA THEY USED
    4. Not only did the authors of the “hockey stick” use temperature proxies that the IPCC had said should not be used; not only did they give these questionable proxies 390 times more weight than other data; but they ALSO LEFT OUT THE TREE-RING DATASET THAT INCLUDED THE MEDIEVAL WARM PERIOD ITSELF!
    5. Then the graph’s authors said in the scientific paper that accompanied their graph THAT THEY HAD INCLUDED THE TREE-RING DATASET FOR THE MEDIEVAL WARM PERIOD THAT THEY HAD IN FACT OMITTED!
    6. The graph’s authors inserted their own “estimates” in place of the data they had left out, BUT DID NOT PUBLISH THE FACT THAT THEY HAD DONE SO.
    7. Worse, THEY HID THE MISSING DATA IN A FILE ON THEIR OWN COMPUTER that they revealingly labeled “CENSORED_DATA”.

    How bad can things get? – but they get worse!

24. #24 Snowman

    July 11, 2009

    Coby – As one British journalist put it, the hockey stick is ‘the most discredited artefact in the history of science’.

    It is disappointing that you try to justify it, and unworthy of you. You obviously have a sound grasp of the science of this topic, but it damages your credibility when you defend the indefensible. It would strengthen your case if you were to say, ok, we got it wrong, and move on to matters where reasonable people may still disagree.

    Of course, this would mean conceding that the Mediaeval warm was true. But there we are. You cannot distort the facts to fit your theory. The theory must be adapted to the facts.

25. #25 Richard

    July 11, 2009

    8. When McIntyre and McKitrick obtained from the authors of the “hockey stick” the computer program they had used in compiling the graph, they found it PRODUCED A “HOCKEY STICK” EVEN WHEN THEY USED RANDOM DATA FROM A TELEPHONE BOOK!
    9. Geophysical Research Letters finally published a paper by McIntyre & McKitrick exposing the defects in the graph (McIntyre & McKitrick, 2005).
    10. “This paper provoked astonishment and dismay throughout the climatological community. That was the first moment at which many honest scientists who had previously accepted the climate scare at face value began to question the methods and the motives of the handful of politicized scientists.”
    11. Three statisticians were engaged by the US House of Representatives (Wegman et al., 2005) to examine the evidence on both sides.
    12. In a damning report, the statisticians confirmed all of the findings of McIntyre and McKitrick to the effect that the graph was defective.
    13. The statisticians also found that a suspicious collection of subsequent papers that had suddenly appeared supporting the assertion that the medieval warm period had not existed.
    14. They found that these had nearly all been written by associates or co-authors of the inventors of the defective graph, and using similarly questionable data and methods!

26. #26 Richard

    July 11, 2009

    15. In the July 2005 hearing, Edward Wegman, a George Mason University statistician, testified on behalf of the mathematicians who reviewed the Mann papers. “The controversy of the [Mann] methods lies in that the proxies are incorrectly centered on the mean of the period 1902-1995, rather than on the whole time period.” He explained that these statistical procedures were capable of incorrectly creating a hockey stick shaped graph.
    16. Gerald North, chair of the National Research Council committee, testified at the hearing that he agreed with Wegman’s statistical criticisms, but said that those considerations “did not alter the substance of Mann’s findings”! (How on Earth is that possible?) North said that large scale surface temperature reconstructions “are only one of multiple lines of evidence supporting the conclusion that climatic warming is occurring in response to human activities.” Effectively bailing out Mann.
    17. However in the detailed 155 page report of the National Academy of Sciences, National Research Council Report, which was also chaired by Gerald North, said differently, though “buried in a lot of genteel and deferential prose”
    18. They accepted McIntyre & McKitrick’s argument that Mann’s method is biased towards producing hockey stick-shaped PCs
    19. That uncertainties had been underestimated
    20. That the bristlecone data, on which the famous hockey stick shape depends, should not have been used.
    21. THEY ALSO EXPRESSED VERY LITTLE CONFIDENCE IN THE IPCC’S CLAIM ABOUT THE 1990S BEING THE WARMEST DECADE IN THE MILLENNIUM. “Very little confidence can be assigned to statements concerning the hemispheric mean or global mean surface temperature prior to about A.D. 900”
    22. “The substantial uncertainties currently present in the quantitative assessment of large-scale surface temperature changes prior to about A.D. 1600 lower our confidence in this conclusion compared to the high level of confidence we place in the Little Ice Age cooling and 20th century warming.”
    23. “Even less confidence can be placed in the original conclusions by Mann et al. (1999) that “the 1990s are likely the warmest decade, and 1998 the warmest year, in at least a millennium” because the uncertainties inherent in temperature reconstructions for individual years and decades are larger than those for longer time periods, and because not all of the available proxies record temperature information on such short timescales.”
    24. However just before this they also slipped in that “..the committee finds it PLAUSIBLE that the Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium.” This enabled Nature, who first published Mann’s work to say in a headline “Academy affirms hockey-stick graph”! and every other tabloid jumped in. Shame on you Nature!

27. #27 Snowman

    July 12, 2009

    Simply magnificent, Richard. I am genuinely looking forward to hearing the response from Coby and the others.

    I really, really hope, Coby, that you won’t disappoint us by quoting some source who disagrees with Richard’s conclusions (the appeal to authority fallacy).

    I hope, instead, that you will argue your case using, as Richard does, primary sources.

28. #28 dhogaza

    July 12, 2009

    15. In the July 2005 hearing, Edward Wegman, a George Mason University statistician, testified on behalf of the mathematicians who reviewed the Mann papers. “The controversy of the [Mann] methods lies in that the proxies are incorrectly centered on the mean of the period 1902-1995, rather than on the whole time period.” He explained that these statistical procedures were capable of incorrectly creating a hockey stick shaped graph.

    When standard rather than uncentered PCA is applied to the data, the same hockey stick shape is generated. When Wegman was asked if he’d done this analysis himself, he said “no”. When asked why not, he said he wasn’t asked to.

    From the scientific, rather than political viewpoint of building mountains of molehills, the question isn’t whether or not Wegman is right that uncentered PCA analysis was the wrong tool. The question is DID IT MAKE A SIGNIFICANT DIFFERENCE.

    Answer: no.

    Mann’s paper from last year used standard PCA, a shitload of new proxy data, and came up with virtually the same result.

    Of course, not all statisticians agree that Wegman’s criticism is valid, anyway.

    Simply magnificent, Richard. I am genuinely looking forward to hearing the response from Coby and the others.

    I’m not going to bother shooting down Richard’s point-by-point rehasing of The Hockey Stick Gospel According To McIntyre. It’s pointless. It’s a combination of molehills posing as mountains, lies, and misdirection.

    Go ahead and believe what you want to believe. In the world of science, it is accepted that recent warming is unprecedented in a least the last few hundred years, most likely at least 1,000, and very likely the last couple of thousand.

    If it weren’t for a few right-wingnut politicians like Inhofe scientists wouldn’t even bother with McIntyre. It’s like fighting creationists or HIV denialists. Pointless except when the lies negatively impact policy.

29. #29 Ian Forrester

    July 12, 2009

    Wegman lost all credibility when he signed the Bali letter. The nonsense in that letter would get a failing grade in any first year statistics class.

    He is just another denier shill. Anyone who believes a word he says is grasping at straws. Of course, that is what you deniers do, grab at straws and make them into strawmen. Such childish behaviour is not an accepted part of the scientific method.

    You deniers can go on all you want, it wont change the science behind climate change but, unfortunately, it is having the tragic consequence of influencing policy.

    This is of course exactly what the Oil Industry wanted in their API memo.

30. #30 dhogaza

    July 12, 2009

    Simply magnificent, Richard. I am genuinely looking forward to hearing the response from Coby and the others.

    I really, really hope, Coby, that you won’t disappoint us by quoting some source who disagrees with Richard’s conclusions (the appeal to authority fallacy).

    So, let’s see, Richard posts a list cut-and-pasted from some denialist website, and it’s “magnificent”.

    While if Coby posts a quote from an actual authority – a climate scientist – he’ll be guilty of “the appeal to authority” fallacy.

    Your small mind works in dishonest, twisted ways, snowman.

31. #31 dhogaza

    July 12, 2009

    17. However in the detailed 155 page report of the National Academy of Sciences, National Research Council Report, which was also chaired by Gerald North, said differently, though “buried in a lot of genteel and deferential prose”

    Having read most of that report myself, I know for a fact that the NAS report was largely supportive of Mann’s conclusions, despite your cherry-picking quotes … sorry … despite your cut-and-paste of cherry-picked quotes … meant to lead one to conclude the opposite.

    This is what I mean about McIntyre and others lying about the NAS report.

    You’ve apparently fallen for it, or are simply dishonest, Richard. Which is it? Are you among the honest fooled, or the dishonest denialsphere?

32. #32 Richard

    July 12, 2009

    Unlike you dhogaza I do not cut and paste I do my own research.

    No one so far as I know have analysed the Hockey Stick saga as I have done above. Certainly not McIntyre and McKitrick, who are too technical for most to understand and not focussed enough on the what the message should be – which is Fraud and Cover-up.

    I for example have downloaded the the National Academy of Sciences, National Research Council Report and read it. I have also read the Chairman Gerald North’s seperate report and testimony, which is a shameful vindication of this fraud. In the National Research Council Report, they did their best and you can see where the Chairman’s heavy handed intervention comes in.

    dhogaza you have lost every “debate” you have had with me. (Actually very short arguments where I have quickly pointed out the flaws you have made).

    In Open Thread you have said “Yes, Richard, and the professional statistician who runs that site, using the same data you claimed to use, shows that you’re wrong.”

    Actually what he said was that my temperature data was “wrong”. He said that his temperature at “11857 yrBP is about -48.3 deg.C”. My temperature is -16.58C.

    Now I know why the discrepancy is there, but can you figure it out? No I bet you cant! Thats because you cannot think critically for yourself, you have to depend and fall back on the crutch of “thousands of scientists say so”. You have to depend on cut and paste and references to sites because you cannot explain things yourself.

    Ok here is the explanation – the difference of 31.72 degrees is because my figures are anomalies from todays date (the year 2000). The rates of climb of temperatures which I have given 4.15C/Century, 2.66C/century, and 0.54C/century are absolutely correct and cannot be challanged and NOR HAVE THEY BEEN.

    You said “Run on over there and continue the debate. This will be fun … science illiterate vs. professional statistician who works with climate scientists (among others).”

    Well alas there will be no debate. My reply to him has been removed and I have been debarred. He does not want a debate or questions. One of the pertinent questions I put to him was – You have claimed that global temperatures have changed extremely slowly in the past, not more than 0.1 deg.C per century, can you tell me how you have determined these global temperatures of the past?

    The professional statistician is scared of a debate with a “science illiterate” – oh yes I know you will have some sarcy comments about this – he is not scared just cant waste his time with this drivel from an illiterate – there I have said it for you. But you can improve on the language – make it more foul.

33. #33 dhogaza

    July 12, 2009

    I for example have downloaded the the National Academy of Sciences, National Research Council Report and read it/

    I’ve read most of it too, and it mostly vindicates Mann’s paper.

    Not that it matters. Mann ’08 is far stronger than the first paper, warming by CO2 rests on first principles not the climate records over the last 2000 years anyway, other researchers have gotten other results using other proxies, Mann ’08 results in a hockey stick w/o bristlecone pine proxies as well as with, etc ad nauseum.

    dhogaza you have lost every “debate” you have had with me. (Actually very short arguments where I have quickly pointed out the flaws you have made).

    1. Science is not a blog debate. Nothing you or I say here changes the state of science one iota.

    2. You “win” because you’re a liar.

    The professional statistician is scared of a debate with a “science illiterate”

    Scared? Doesn’t care to have his time wasted by yet another dishonest, lying, science-illiterate science-denier.

    Ok here is the explanation – the difference of 31.72 degrees is because my figures are anomalies from todays date (the year 2000).

    Yes, what you said there was:

    From 11,857 BP to 11,558 BP, 299 years, the temperatures climbed from -16.58C…

    That’s a false statement. If you use anomalies, you must SAY you are using anomalies.

    Is this your idea of scoring a point? Presenting an anomaly as temperature, then when it’s pointed out that your temp figure is wrong, saying “gotcha!”?

    That makes you a liar, Richard, not news but nice to see it made so obvious and nice to see you admitting it, though apparently not with the sense of shame one would hope for.

    Now I know why the discrepancy is there, but can you figure it out? No I bet you cant!

    You’re right, actually, I didn’t figure it out because I didn’t imagine you’d lie so blatantly. I now know not to trust *anything* you post.

    His main point, though, was that Greenland is not the world. The ice core data gives regional information only and can’t be used to prove or disprove past worldwide climate trends. From the GISP2 site:

    Now that the longest ice core record from the Northern Hemisphere is a reality, it is time to develop new ice core records for the Southern Hemisphere and fill in regional details throughout the Earth.

    They don’t claim that the Greenland ice core data says anything about global climate changes during those periods of time. Just the opposite, they talk about the need for data from other portions of the world to FILL IN REGIONAL DETAILS THROUGHOUT THE EARTH.

    His pointing out that the temps were not correct was an aside, and he was right that your stated figures were incorrect, and he was right in his main point, that the GISP2 data doesn’t tell us that the global climate changed at the same rate as did conditions at Greenland.

34. #34 R James

    July 12, 2009

    Despite all the above debate, I look at Mann’s hockey stick, and as I said before, it fails to show the little ice age (Maunder period), and the Medieval warm period, and other. It’s wrong. No amount of debate can change that.

35. #35 dhogaza

    July 12, 2009

    Despite all the above debate, I look at Mann’s hockey stick, and as I said before, it fails to show the little ice age (Maunder period), and the Medieval warm period, and other. It’s wrong. No amount of debate can change that.

    Why would you expect a regional phenomena to dominate a global signal?

36. #36 R James

    July 12, 2009

    The coincidence of the little ice age with the Maunder period is too strong to ignore. I would expect it to have been global. Also, the hockey stick was too flat for too long leading up to recent times. Climate in the past hasn’t reacted this way. It has significant peaks and troughs.

37. #37 dhogaza

    July 12, 2009

    This is typical of the science on the MWP:

    It has frequently been suggested that the period encompassing the ninth to the fourteenth centuries A.D. experienced a climate warmer than that prevailing around the turn of the twentieth century. This epoch has become known as the Medieval Warm Period, since it coincides with the Middle Ages in Europe.

    So far so good …

    In this review a number of lines of evidence are considered, (including climatesensitive tree rings, documentary sources, and montane glaciers) in order to evaluate whether it is reasonable to conclude that climate in medieval times was, indeed, warmer than the climate of more recent times. Our review indicates that for some areas of the globe (for example, Scandinavia, China, the Sierra Nevada in California, the Canadian Rockies and Tasmania), temperatures, particularly in summer, appear to have been higher during some parts of this period than those that were to prevail until the most recent decades of the twentieth century.

    Hmmm …

    These warmer regional episodes were not strongly synchronous.

    Not strongly synchronous. In other words, warmer for a bit over here, but not over there, then over there, but not over here, etc.

    This does not a global climate signal make.

    Evidence from other regions (for example, the Southeast United States, southern Europe along the Mediterranean, and parts of South America) indicates that the climate during that time was little different to that of later times, or that warming, if it occurred, was recorded at a later time than has been assumed.

    Even less synchronousity – if it happened at all.

    Taken together, the available evidence does not support a global Medieval Warm Period, although more support for such a phenomenon could be drawn from high-elevation records than from low-elevation records.

    Take away point – the available evidence does not support a global Medieval Warm Period.

    Now, if the available evidence does not support a global MWP, why would you expect analysis of various proxies by Mann would result in the appearance of a global MWP?

    Mann ’08 uses a *lot* more proxies than his first paper. The evidence for a global MWP just isn’t there in the available physical evidence.

    Now, if more proxies giving greater coverage of the globe are uncovered which in the future shows strong evidence for a global MWP, then Mann’s reconstruction methodology, using this FUTURE EVIDENCE WHICH DOESN’T EXIST YET, would also show a MWP.

38. #38 dhogaza

    July 12, 2009

    The coincidence of the little ice age with the Maunder period is too strong to ignore. I would expect it to have been global.

    “I would expect it”. Nevermind the lack of physical evidence. Blog science doesn’t need to effing evidence. Doesn’t match your intuition means … science must be wrong.

    Feh.

39. #39 dhogaza

    July 12, 2009

    Also, the hockey stick was too flat for too long leading up to recent times. Climate in the past hasn’t reacted this way. It has significant peaks and troughs.

    This is known as an “argument from personal incredulity”, a standard argumentation technique employed by science denialists.

    What evidence do you have that your belief matches the expectations of climate scientists?

40. #40 Richard

    July 12, 2009

    dhogaza -
    “Yes, what you said there was:
    From 11,857 BP to 11,558 BP, 299 years, the temperatures climbed from -16.58C…
    That’s a false statement. If you use anomalies, you must SAY you are using anomalies.
    Is this your idea of scoring a point? Presenting an anomaly as temperature, then when it’s pointed out that your temp figure is wrong, saying “gotcha!”?
    That makes you a liar, Richard, not news but nice to see it made so obvious and nice to see you admitting it, though apparently not with the sense of shame one would hope for.”

    dhogaza – (I must keep myself from saying “you idiot”, but thats what the above outburst makes you). Here is an explanation that I hope even idiots can understand.

    I grab data from the net wherever I can find it. I didnt realise that it was anomalies rather than actual temperatures, till your “professional statistician” said that the temperature was actually -48.3 deg.C in the year 11857 yrBP against what I had -16.58C. He didnt tell me what was wrong I DEDUCED IT, something you are incapable of doing. It doesnt make my statement false – see below as I give a little maths lesson for dummies.

    1. What I said – “From 11,857 BP to 11,558 BP, 299 years, the temperatures climbed from -16.58C to -4.17, 12.41C, thats a rate of 4.15C/Century.”

    2. I could have left out – (FROM -16.58C TO -4.17C), without affecting the correctness of the statement. That is:

    From 11,857 BP to 11,558 BP, 299 years, the temperatures climbed BY 12.41C, thats a rate of 4.15C/Century.

    Or if you are very fussy then

    3. From 11,857 BP to 11,558 BP, 299 years, the temperatures climbed from {-16.58C + (-31.72C)} to {-4.17 + (-31.72C)}, 12.41C, thats a rate of 4.15C/Century.

    Notice the two -31.72C’s cancell each other out?

    You are obviously quite challenged with simple arithmetic (addition and subtraction), but do even you understand now?

    What was important in my statement was that over a period of 3 centuries, as the Earth climbed out of the last ice-age, the temperatures rose at the rate of 4.15C/Century. That is the truth.

    Compare this with what your “professional statistician” said in his blog.

    “It’s also worth noting that the deglaciation which takes us from a glacial period to an interglacial is fast — on geologic timescales — BUT SLOW AS MOLASSES COMPARED TO MODERN GLOBAL WARMING. THE TOTAL TEMPERATURE CHANGE OF 5 OR 6C FROM GLACIAL TO INTERGLACIAL TYPICALLY TAKES 5000 YEARS OR MORE; THE RATE OF WARMING IS GENERALLY LESS THAN 0.1C/CENTURY.

    Well here is the evidence that temperatures went up at the end of the last deglaciation not by 5 OR 6 oC, but by a whopping 12.41 oC, in not 5,000 years but a mere 299 years.

    So which is the false statement?

    That is the important point not whether we are computing from anomalies or actual temperatures. DO YOU GET IT YOU —–?

41. #41 Richard

    July 12, 2009

    “They don’t claim that the Greenland ice core data says anything about global climate changes during those periods of time. Just the opposite,..” Oh really?

    From:
    http://en.wikipedia.org/wiki/Younger_Dryas#The_end_of_the_Younger_Dryas

    “Measurements of oxygen isotopes from the GISP2 ice core suggest the ending of the Younger Dryas took place over just 40 – 50 years in three discrete steps, each lasting five years. Other proxy data, such as dust concentration, and snow accumulation, suggest an even more rapid transition, requiring a ~7 °C warming in just a few years;[5][6][14][15] the total warming was 10°±4°.[16]

    The end of the Younger Dryas has been dated to around 9620 BC (11550 calendar years BP, occurring at 10000 radiocarbon years BP, a “radiocarbon plateau”) by a variety of methods, with mostly consistent results:

    11530±50 BP — GRIP ice core, Greenland [17]
    11530+40-60 BP — Kråkenes Lake, western Norway. [18]
    11570 BP — Cariaco Basin core, Venezuela [19]
    11570 BP — German oak/pine dendrochronology [20]
    11640±280 BP — GISP2 ice core, Greenland [14] ”

    From:
    http://www.pnas.org/content/97/4/1331.full

    “The Greenland records show that climate changes have been VERY LARGE, RAPID, AND WIDESPREAD.”

    “The relative changes in methane concentrations in Greenland and Antarctica indicate that the increase at the end of the Younger Dryas involved both tropical and high-latitude sources (24, 25), and that the previous large increase about 14,700 years ago was dominated by the tropics (25).”

    “Other Greenland data also show that the climate changes were GEOGRAPHICALLY EXTENSIVE. The isotopic composition of dust in Greenland ice indicates an Asian source (19), and the sea salt is oceanic. The large changes observed in dust and sea salt indicate reorganizations of weather patterns well beyond Greenland.”

42. #42 Riku

    January 8, 2010

    If I might once again interrupt, might I ask the people around here, how accurate is this chart.

    http://www.drroyspencer.com/wp-content/uploads/UAH_LT_1979_thru_Dec_09.jpg

    I found this few days ago and I found it odd that is showed a rather stable line from 2002 to 2006, with hardly any warming from the first records from 1971. Now I might understand how the beginning can be explained by the misscalculation, but the later data shows on itself no clear warming when that El Nino is there.

    Would someone be kind enough to help a newbie in need and clear this for me? Is this chart simply without accuracy or what am I missing?

43. #43 GFW

    January 8, 2010

    Hi Riku,

    First up, the data is too noisy to decide there are different regions like “flat since 2002″. So one must do the simplest thing and take all 30 some years of data there and fit a straight line to it. That will definitely have a positive slope. My eyeball guess is that one would get 0.15 C/decade or a hair less. Let’s say 0.13 to 0.15. The GISSTemp ocean-land surface numbers give something like 0.17 to 0.18 C/decade. So the UAH is showing warming, just a little slower than the GISSTemp data does.

    Why might that be?

    The UAH numbers are (by the nature of how the measurement is taken – I’d need someone more technical to explain this further, but it’s because it’s strongly affected by water vapor) more heavily weighted to counting the tropics than high latitudes. That’s why the 1998 El Nino is so much bigger on satellite graphs than surface temperature graphs.

    So, because global warming is strongest at high latitudes (aka “polar amplification”) the UAH graph shows slower warming. It’s showing the truth – lower latitudes are warming at a slower rate than high latitudes.

44. #44 Riku

    January 9, 2010

    Oh that makes sense, thanks again GFW.

45. #45 Trevor

    May 11, 2010

    How did this discussion get off on Mann’s discredited hockey stick? It’s not even worth discussing anymore. And this isn’t the place for it anyway.

    With respect to the lack of tropospheric warming, Coby claims, “However, it turns out that some additional errors were uncovered and the MSU Satellite temperature analysis now shows warming well in line with model expectations.” This is a falsehood. Yes, there were some errors discovered in one of the two satellite records (UAH), and the corrections were made, so that they now show a more positive temperature trend, BUT STILL WELL BELOW THE TREND PREDICTED BY THE GENERAL CIRCULATION MODELS. The other dataset (RSS) always showed a more positive tropospheric temperature trend than UAH, and the correction to UAH didn’t change that. But even the RSS dataset shows a lot less tropospheric warming than the models predict.

    Here are the facts:

    1. According to Fu et al (2004), “GCM studies have predicted a global ratio of ~1.2 (ref. 8) and a tropical ratio of ~1.54 (ref. 14).”

    2. If you multiply the model-predicted global ratio of tropospheric to surface temps (1.2) by the surface temperature trend (+0.17 K/decade) over the last 30 years, you can see that tropospheric temperatures SHOULD HAVE (according to the models) increased at a rate of about 0.20 K/decade.

    3. The UAH dataset shows a warming trend of 0.047 K/decade (yes, that’s AFTER the corrections). RSS shows a warming trend of 0.090 K/decade.

    4. OVER HALF of the model-predicted warming of the troposphere simply did not occur. And that’s being generous and using the RSS data. If you use the UAH data, over three-fourths of the model-predicted tropospheric warming did not occur.

    Now, those are the facts, and the Wikipedia article that Coby references bears them out – see for yourself.

    Various authors have attempted to “explain” the lack of real-world confirmation of the model-predicted tropospheric hotspot, and I would be glad to debate the merits of any individual “explanation”. But the DATA, as it stands now, with all corrections included, completely FAILS to confirm the tropospheric hotspot predicted by the models. Even the Pro-AGW papers confirm this. Indeed, they wouldn’t even TRY to “explain” the difference between model predictions and real world observations if that difference did not exist.

    Regards,
    Trevor

46. #46 GFW

    May 11, 2010

    Hey Trevor. You’re lying. It’s possible there are UAH and RSS datasets that show the low warming trends you mention, but they sure as heck aren’t the lower troposphere datasets. RSS shows 0.15-0.16 and UAH shows 0.13 to 0.14 for the lower troposphere. Both are within error bars of the ground station datasets (Hadley and GISS) which are around 0.17.

    Your numbers are probably (a) Raw channel 2, which is a mix of the entire troposphere and some of the stratosphere, and (b) date from before Spencer and Christy were forced to acknowledge the errors in the UAH dataset processing.

    As for those ratios of ground to troposphere you mention, that’s a theoretical maximum if you could isolate the exact location in the mid-troposphere experiencing the most warming. Fu et. al. (2004) claims to have done that, and his results are consistent with that prediction, for the RSS dataset. Frankly, I’d want to look into whether both sides of that comparison have changed any since 2010, but it’s clear that Fu et. al., plus our later knowledge of the problems with UAH completely contradicts your conclusions.

47. #47 GFW

    May 11, 2010

    Errata.
    Obviously I meant “since 2004″ or “between 2004 and now (2010)”, not since 2010.
    The last sentence could use a comma between “UAH” and “completely”.
    And of course the trends in the first paragraph are degrees C (or K) per decade.

48. #48 Trevor

    May 11, 2010

    Hey GFW.

    Of course my trends are not the lower troposphere trends. Because the lower troposphere is NOT where the models predict the hotspot to be. The models predict the hotspot to be at 10-12 km altitude. Given that the troposphere, at it’s maximum thickness, is only 20 km thick, the hotspot should be ABOVE the middle of the troposphere, where the T2 reading is taken. Not in the lower troposphere, where the TLT reading (your 0.13-0.16 K/decade) is taken. (Note that Fu et al used the T2 temperature record (though he applied a rather dubious “correction” to it), not the TLT record.)

    The ratios stated by Fu were not claimed to be a “hypothetical maximum”. In fact, they’re not Fu’s numbers at all, but come from two references he cited. I tried to bring up the references so that I could post a direct source for those ratios, but alas, the papers were not available without a subscription. And since I’m NOT a paid schill for the oil companies, I can’t afford those subscriptions. So, on that, I’ll take Fu at his word. Unless, of course, you can provide me a link to the full texts of:

    Hansen, J. et al. Climate forcings in Goddard Institute for Space Studies SI2000 simulations. J. Geophys. Res. 107, doi:10.1029/2001JD001143 (2002).

    and

    Santer, B. D. et al. Influence of satellite data uncertainties on the detection of externally forced climate
    change. Science 300, 1280–1284 (2003).

    I acknowledge that, in toto, the Fu et al paper finds that the observed tropospheric warming (after “correction”) is consistent with the models. However, to arrive at this result, they have to apply a dubious adjustment to the mid-tropospheric temperature trend. Yes, Fu contradicts my conclusions. Because Fu CHEATED!

    Fu’s paper is based on the notion that the T2 temperature reading is “contaminated” by the signal from the stratosphere, which is undoubtedly cooling. Apparently, the satellites’ microwave sending units (MSUs) are not fine-tuned enough to pick out a temperature at a specific altitude, but instead result in an average temperature over a wide range of altitudes, centered on the mid-troposphere, but including both parts of the stratosphere and the surface. So, Fu wanted to remove the “contamination” of the stratosphere from the tropospheric temperature trend.

    So Fu came up with a combination (T[850-300]) of T2 (mid-troposphere) temps and T4 (stratosphere) temps, based on an OLS (ordinary least squares) regression. The “ground truth” (or in this case, 10-km-above-ground-truth), or for the dependent variable T[850-300] was taken from radiosonde (weather balloon) data. Here’s my first problem with this method. If you believe that the radiosonde tropospheric temperature record is any good, why not just use it DIRECTLY? The answer, of course, is that the radiosonde record is even further away from what the models predict than the satellite records are (which was the initial source of inconvenience for the hotspot theory). So the alarmists have come with a dubious reason to completely throw out the radiosonde data (and Fu, specifically, rejected the radiosonde data early on in this paper). Right or wrong, however, once the radiosonde data has been thrown out, you can’t just go back and use it for something else. If it’s wrong it’s wrong, and you can’t use it anymore. If it’s right, it’s right, and there’s no need to use any other temperature record, let alone some dubiously-constructed amalgam of satellite data from two different channels.

    So, Fu estimates his OLS equation, and, at least the way he presents it, it looks damned good, with a correlation coefficient of 0.982. But here’s my second problem with the method. Fu “neglects” to mention the t-statistics of the individual coefficients, which would tell us how important the two explanatory variables (T2 and T4) are, individually, in predicting the value of T[850-300]. It might be that T2 has a far more significant impact on T[850-300] than T4 does. Indeed, if you look at Fu’s own Figure 2, it’s quite obvious that that is the case – the plot for T[850-300] is damned near right on top of that of T2. I suspect that the significance of T4 in the OLS equation is actually very low, and that you could get a correlation coefficient just as high (after adjusting for degrees of freedom) by completely throwing out T4. The correlation coefficient, though impressive, is, by itself, worthless for evaluating how successful the addition of T4 to the equation was in predicting T[850-300].

    Here’s my third problem with Fu et al. If the mid-tropospheric temperature reading T2 is “contaminated” by the stratospheric temperature, then it is (at least) equally contaminated by the surface temperature. In fact, Fu’s own Figure 1a shows that nearly twice as much contamination of the T2 temperature comes from the surface as comes from the stratosphere. But Fu made no attempt at removing the contamination by the surface temperature (or even, for that matter, to estimate how much contamination is coming from the surface), like he did for the stratospheric temperature. The contamination of T2 by the stratosphere is negative (and thus, removing it would increase the tropospheric temperature trend). The contamination from the surface is positive (so removing it would decrease the tropospheric temperature trend). So removing one and not the other clearly biases the result in a positive direction.

    Furthermore, the upward trend in surface temperature (0.17 K/decade) is larger in magnitude than the downward trend in stratospheric temperature (Fu says -0.5 to -0.9 K/decade). So, combined with the higher influence of surface temps on tropospheric temps, it’s clear that a similar adjustment for surface temps would far outweigh Fu’s adjustment for stratospheric temps. And if surface temps had been included in Fu’s regression analysis, I daresay the coefficient would have a much higher t-statistic than the T4 coefficient had. Based on this, it’s obvious that a FAIR adjustment, for the contamination of BOTH stratospheric AND surface temperatures, would result in a significant DECREASE in the T2 temperature trend, rather than the increase shown by Fu by focusing on removing only the negative contamination.

    Cherry-picking. Plain and simple. Cut and dry. I won’t call you a liar, GFW, like you did to me, because it’s possible you’re just deluded. But I will call Fu a liar. He knew better.

    Regards,
    Trevor

49. #49 dappledwater

    May 11, 2010

    How did this discussion get off on the tropical tropospheric hotspot hokum? It’s not even worth discussing anymore. And this isn’t the place for it anyway.

50. #50 crakar24

    May 11, 2010

    Great post Trevor, as you can see from #49 you will not get a reasoned response from around here.

51. #51 Trevor

    May 12, 2010

    An errata of my own:

    In my third and final point regarding Fu et al (2005), I mentioned that upward trend in surface temperatures (+0.17 K/decade) was larger in magnitude than the downward trend in stratospheric temperatures (which Fu reported as between -0.5 and -0.9 K/decade). I had a brain fart there. Mea culpa. Even the smaller (absolute) value of -0.5 is larger than 0.17. So, at least according to Fu, the stratospheric temperature trend is larger in magnitude than the surface temperature trend. However, more recent studies have shown that much of the negative trend in stratospheric temperatures was due to ozone losses, and now that ozone levels are recovering, the trend has actually reversed to positive. It is yet to be determined what the overall trend will be when ozone levels have fully recovered, but it is clear that the overall trend, over 1978 to 2004, is much smaller in magnitude (though still negative) than Fu what Fu claimed, in the neighborhood of -0.2 – -0.25 K/decade. This, of course, is still larger in magnitude than the trend in surface temperatures, so I was still wrong even with the updated analysis.

    Also, I said that the contamination of the T2 temperature reading by the surface temperature is positive, and that removing this contamination would result in a lower T2 trend. This is not necessarily true. IF the GCMs are correct, and the ACTUAL mid-tropospheric temperature trend is larger than the surface temperature trend, then the surface temperature trend negatively affects T2 temperature, and removing that bias would make the mid-tropospheric temperature trend more positive. However, if the actual mid-tropospheric temperature trend is smaller than the surface temperature trend, then my original point is valid; the surface temperature trend is a positive contamination of the mid-tropospheric temperature trend and removing it from the T2 trend would lower that trend. But the point is, we DON’T KNOW what the ACTUAL mid-tropospheric temperature trend is. That’s what Fu was trying to establish. He can’t just ASSUME that the models are correct in attempting to prove that the models are correct. That’s circular reasoning. What he should have done was included a term for the surface temperature in his regression analysis, the same as he did for the T4 stratospheric temperature, and FIND OUT what whether removing the surface temperature trend has a positive or negative effect on the T4 trend.

    (Actually, I suspect that Fu did just that, but discovered that including the surface temperature in the regression proved inconvenient with respect to what he was trying to show, in that either 1) it reduced rather than increased the mid-tropospheric temperature trend, or 2) it reduced the t-statistic for the T4 coefficient to complete insignificance, or 3) it reversed the sign of the T4 coefficient. Of course, Fu wouldn’t report any of these outcomes, but would instead throw out the surface temperature and run the regression again, resulting in what he eventually published.)

52. #52 Trevor

    May 12, 2010

    (Correction)

    In last sentence of the second-to-last paragraph, delete
    “what” and replace “T4 trend” with “T2 trend”.

53. #53 Dappledwater

    May 12, 2010

    “Right or wrong, however, once the radiosonde data has been thrown out, you can’t just go back and use it for something else. If it’s wrong it’s wrong, and you can’t use it anymore. If it’s right, it’s right, and there’s no need to use any other temperature record, let alone some dubiously-constructed amalgam of satellite data from two different channels.” – Trevor.

    Maybe that’s how deniers think science works, but in the real world, not so much.

54. #54 Dappledwater

    May 12, 2010

    “Yes, Fu contradicts my conclusions. Because Fu CHEATED!” – Trevor.

    Tsk, tsk, more character assassination of scientists from those unable to accept reality.

    Above you accept that the stratosphere is definitely cooling – a fingerprint of the enhanced Greenhouse Effect, that the surface is warming and yet you seem to have difficulty accepting that the tropical troposphere is warming too?. Weird.

    For any interested readers, here’s a summary of the situation:

    http://www.realclimate.org/docs/santer_etal_IJoC_08_fact_sheet.pdf

55. #55 crakar24

    May 12, 2010

    The bottom line DW is that the models predict the upper troposphere should show a higher warming rate than the surface. As real world observations show (sat or radiosonde) this is not the case then the only logical conclusion that one can arrive at is the MODELS ARE WRONG.

    However i know that faith plays a large part in how you interpret the world you live in and no matter what empirical evidence there is you simply will not accept it and continue to believe the models are correct.

56. #56 GFW

    May 12, 2010

    Ah yes, I was just coming back to concede that “lying” was a little strong, but it’s more pithy than “mislead, on a tangent, and avoid updated knowledge”.

    The link that contains DW’s link to Santer et. al. is http://www.realclimate.org/index.php/archives/2008/10/tropical-tropopshere-iii/

    Obvious things to note, beyond Santer et. al.’s more careful consideration of statistics are
    1. The rate of surface warming in the tropics is lower than the global rate (the flip side of polar amplification). So the tropical mid-troposphere warming isn’t some super-strong signal that should be easy to find just because it’s 1.5 times the surface warming.
    2. As you belatedly realized, because the mid-troposphere warming is a maximum (less warming below, and less warming (and eventually cooling) above) it’s hard to see in the satellite channels, which cover such wide altitude ranges. Santer et. al. clearly claim to have found it in the satellite data though, and I believe this work has stood up … unlike so much of Spencer and Christy’s.
    3. The height and strength of the maximum can vary with weather, so you need a lot of measurements. That variability is what I meant when I said it was a theoretical maximum. There’s no guarantee you’ll find it without a lot of measurements over a climatologically significant time period.
    4. As you can see from the figure on the page I linked to, the sondes give a very wide range of results, but they do show a hotspot.

    So, the big picture is: the *surface* is warming at ~0.17C/decade. There is a mid-tropospheric region of faster warming, as predicted for any overall warming. It’s hard to measure but so far measurements are consistent with theory. There is definitely significant and easy-to-measure stratospheric cooling, the specific signature of greenhouse-gas driven surface warming. So … what’s your objection again? The eastern US had a snowy winter? Arctic ice briefly reached near-normal levels before falling back to the trend? Al Gore is fat?

57. #57 Dappledwater

    May 12, 2010

    “However i know that faith plays a large part in how you interpret the world you live in and no matter what empirical evidence there is you simply will not accept it” – Crakar.

    Good to see you have a sense of humor. And seeing as you didn’t read the link I provided here are some relevant bits:

    “This Figure illustrates that both tropical surface and tropospheric temperatures
    have gradually warmed since 1979. Superimposed on this overall warming is
    climate “noise”, which in this case arises primarily from El Niños and La Niñas.”

    “Unlike Douglass et al., however, we found that most of our tests involving
    temperature trends in individual layers of the troposphere did not show
    statistically significant differences between models and observations. This result
    was relatively insensitive to which model or satellite dataset we chose for the
    trend comparison.”

    “The situation was a little more complex for tests involving the trend difference
    between surface and tropospheric warming rates. In this case, the statistical
    significance of the differences between models and observations was sensitive
    to our choice of observational datasets. When we used a satellite-based
    tropospheric temperature dataset developed at Remote Sensing Systems (RSS)
    in Santa Rosa, California, we found that the warming in the tropical troposphere
    was always larger than the warming at the surface.J This behavior is consistent
    with the behavior of the climate models and with our understanding of the
    physical processes that govern tropospheric temperature profiles. It is contrary
    to the findings of Douglass et al.”

    The real funny thing is Crakar, that Trevor nitpicks but doesn’t comprehend the implications of the warming surface temperature and cooling stratosphere, this despite all his flowery prose. Maybe he’s used to a credulous audience?.

58. #58 crakar24

    May 12, 2010

    Are we reading the same thing DW? I dont think we are.

    The study i have in front of me states that the DCPS07 study shows the upper troposphere (10 to 12K above the tropics) is not warming at a greater rate than the surface. In fact the “hot spot” area had cooled compared to the surface.

    A concerted effort was then launched to prove this wrong and i quote “The general tenor of these
    assessments is that structural uncertainties in satellite- and
    radiosonde-based estimates of tropospheric temperature change are currently large”

    This resulted in CCSP; Karl et al., 2006 to report “advances in identifying and adjusting for inhomogeneities
    in satellite and radiosonde data had helped to resolve the
    discrepancies described above, at least at global scales”

    He continues

    “For month-to-month and year-to-year temperature
    changes, all satellite and radiosonde datasets
    showed amplification behaviour consistent with model
    results and basic theory. For multi-decadal changes, however,
    only two of the then-available satellite datasets (and
    none of the then-available radiosonde datasets) indicated
    warming of the troposphere exceeding that of the surface”

    Karl et al came to one of two conclusions, the first bieng the models are wrong and the second being “residual errors in many
    of the satellite and radiosonde datasets used in the CCSP
    report”

    So in essence DCPS07 found there be no evidence of the hot spot predicted by the models.

    Karl et al suggested structual uncertainties was the problem however this still did not find the missing hotspot. Left with little choice they then claimed the hotspot is there but we cant see it due to residual errors.

    Santer et al agree and once again i quote “In view of the large structural uncertainties in
    the observations, the consistency of model amplification
    results across a range of timescales, and independent
    evidence of substantial tropospheric warming (Santer
    et al., 2003, 2007; Paul et al., 2004; Mears et al., 2007;
    Allen and Sherwood, 2008a,b), this was deemed to be
    the more plausible explanation.”

    Santer then prattles on about why his study is better than theirs etc but essentially he along with Karl et al claim the difference in temp/rate is gobbled up in structual uncertanties and erroneous data.

    Did either Karl or Santer measure a temp rate greater than the surface? No they did not. Has the hot spot been found? No it has not. What ramifications does this have? Well its simple the hotspot is made up of all the water vapour which is supposed to build up in the atmosphere due to a +ve feed back from CO2. But yet it cannot be found, just like Trenberths missing heat which now resides at the bottom of the ocean which of course is something else we cannot measure.

    Rest assured DW your faith will see you through these difficult times.

59. #59 crakar24

    May 12, 2010

    Forgot the link

    https://publicaffairs.llnl.gov/news/news_releases/2008/NR-08-10-05-article.pdf

60. #60 Dappledwater

    May 13, 2010

    “The study i have in front of me states that the DCPS07 study shows the upper troposphere (10 to 12K above the tropics) is not warming at a greater rate” – Crakar.

    Keep up Crakar!, that’s the study whose flawed methodology was detailed in the link I provided!.

    Now you I can understand getting it all wrong, but those guys?, aren’t they supposed to be scientists?. The warming surface temperatures and cooling stratosphere should have been a dead giveaway, but those guys missed it.

    Crakar the mid tropospheric warming isn’t just a feature of the GCM’s, or of Anthropogenic Global Warming, it’s one of the fundamentals of atmospheric physics, i.e. it’s how we expect the atmosphere to respond to any surface warming. That’s why it’s surprising Douglas, Christy et al, didn’t thoroughly check their work & conclusions before publishing.

    A warming surface temperature will see an increase in water vapor and a corresponding change in the moist adiabatic lapse rate. In a nutshell, the increased water vapor is able to liberate more latent heat as air rises in the atmosphere and condenses at it’s dew point. Ergo both processes should see a rise in the mid troposphere temperatures, above that of the surface.

    “Did either Karl or Santer measure a temp rate greater than the surface?” – Crakar

    Santer et al 2008?, definitely. See link above. And text:

    “When we used a satellite-based tropospheric temperature dataset developed at Remote Sensing Systems (RSS) in Santa Rosa, California, we found that the warming in the tropical troposphere was always larger than the warming at the surface. This behavior is consistent with the behavior of the climate models and with our understanding of the
    physical processes that govern tropospheric temperature profiles. It is contrary
    to the findings of Douglass et al.”

61. #61 Alan Pickman

    May 25, 2010

    Peter Taylor is essentially saying the Earth is cooling in his book Chill. We need someone to take a long critical look at that book, as there don’t seem to be any critical reviews on the net. I think that Taylor will turn into another Ian Plimer under scrutiny.

62. #62 Meghal Jani

    May 9, 2011

    There are two types of temperature data. One is measured by thermometer. This thermometer data is flawed because this depends on where thermometer is located at. In last 40 years, at least 25% of thermometer stations have been shut down. Almost all of them used to be in extremely cold weather. There is a very decent youtube presentation for that http://www.youtube.com/watch?v=58mDaK9bH5o. Moreover, who can forget climategate, where fraud scientists were found to be deliberately manipulating temperature data? What makes you think that they stopped their fraud art now? The second temperature data is from satellite. This satellite data has already been manipulated by NASA. NASA has changed its computer programs to make global warming rook real. Here is the source http://www.theregister.co.uk/2008/05/02/a_tale_of_two_thermometers/

63. #63 mandas

    May 9, 2011

    So let’s get this straight shall we then Meghal.

    Thermometer temperatures are flawed because the locations are bad.

    Satellite temperatures have been manipulated by NASA.

    So, since we have no usable temperature data, we should not use it in our assessment of climate change. Fair enough? Then how can we say one way or the other whether the climate is changing or not?

    I know – let’s look around at any changes in the ecosystem.

    Oh look! Arctic sea ice melting. Greenland losing ice mass. Sea levels rising. Glaciers disappearing. Flowers blooming early. etc, etc, etc.

    What does that say to you? Or do you want to put your hands over your eyes and your fingers in your ears and go lalala and pretend you can’t see that as well?

    Idiot!

64. #64 Chris S.

    May 10, 2011

    Yeah mandas, those pesky plants* and animals**, they must be in on the conspiracy too! I bet NASA signed them up when they promised not to put any dogs in orbit like the Russians did – I hear they signed a treaty with King Louis (the jungle VIP).

    *http://nora.nerc.ac.uk/8388/

    **http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2486.2010.02382.x/abstract

65. #65 Wow

    May 10, 2011

    There is also the movement of the gardener’s climatic warmer growing zones northwards. I guess that the gardeners of the world are in on the “scam” too.

    Well, it’s either that or the temperatures are changing climatically.

66. #66 Wow

    May 10, 2011

    “Why would you expect a regional phenomena to dominate a global signal?”

    Also, what do these people who look at regional historical data make of the fact that regions over the pole have warmed by over 6C? Compared to the maximum extent of the Central Europe readings given which were less than 4C, this warming is higher than the MWP, which, by the way, has been explained and fits within a forcing sensitivity that leads to about 3C per doubling of CO2 or equivalent GHG forcing.

    So if you accept MWP readings, you have to accept about 3C per doubling.

67. #67 Wow

    May 10, 2011

    “Am I wrong or does the linear regression of the data start a couple of years after the satellite data?”

    You can’t draw a line between one point. So your first point cannot be used. You can’t draw a line and ascertain a variation from only two points, you need three.

68. #68 Wow

    May 10, 2011

    Richard, to your gish gallop, the answers:

    1) False. Many proxies were used.

    2) False. Tree rings from some few trees in the north have been affected by other factors such as acid rain and other pollutants. And, since the IPCC do no research themselves, they would not have advices anything to Mann. Twice wrong. And the proxies work before heavy industrialisation based pollution affected the trees.

    3) False.

    4) False again (see #2, IPCC made no such assertion and #3, so you’re double-dipping here twice), they also didn’t exclude proxies from the MWP. They included the period the peak of the MWP existed for in europe.

    5) Since #4 was wrong, this is again double-dipping and again wrong for the same reasons.

    6) False, they used actual thermometers on the graph and clearly labelled them as such.

    7) False.

    8) False. The data was already available to McIntyre from the owner of the Yamal dataset. The pestering was merely to fabricate a story of hiding the data: the data was already there and available. And the “pink noise” only produced a hockey stick that was

    a) much smaller than the hockey stick from readings
    b) deleted any graphs that didn’t produce a hockey stick

    NOTE: funny how you don’t care about M&M hiding data and throwing away graphs they don’t like.

    9) And a rebuttal from several scientists was upheld: M&M’s concerns were not valid. Worse, their methodology was far more flawed.

    10) What caused astonishment was M&M’s paper was so badly written, so full of errors and yet still published. NOTE: published, not peer reviewed. This was the first time many honest scientists saw the paucity of argument against AGW.

    11) Wegman’s report was proven so full of errors it was nulled. It was false to such an extent that their work proved that a method that NOBODY USED wouldn’t produce reliable results.

    Just as well nobody other than Wegman used it.

    Oh, by the way, Wegman’s reports are being investigated for malfeasance and professional misconduct.

    12) Yes, the report was damning. It was, however false. Mann didn’t use the method Wegman used so therefore proved nothing about the Mann paper. It’s damning Wegman, mind with the investigations being done for fraud, IP infringement and misrepresentation.

    13) They asserted such, but their assertions were shown false. Blind test results with the data on professional statisticians produced the same results as Mann had. The statisticians knew nothing about the dataset except the values (leave out words “temperature” and “date” and you can’t tell what the data is about).

    14) Wegman’s report was written by an intern and used papers produced by a small circle of denialists such as McI. They also didn’t find any such evidence, though this lack of proof did not stop them asserting it. Nor you.

    15) GMU are dragging their feet about investigating Wegman, but he is being investigated for fraudulent misconduct. Again, the method Wegman used was not a method used by anyone else, so his paper could not be considered as reflecting upon Mann’s work. This is about the 9th time you’ve said this, you certainly like to repeat yourself.

    16) And Gerald North is wrong. This is not an unheard of occurrence. Several subsequent reports and investigations have refuted Wegman’s report. His finances also heavily rely upon contributions from the fossil fuel industries and associated lobby groups.

    17) A repeat of #16.

    18) No, they found that M&M had used the wrong analysis and had drawn conclusions impossible to state from the subset they decided to work with.

    19) Yes, the uncertainties of the M&M paper analysis were ignored.

    20) The bristlecone pine data was removed from the analysis by Mann and the results were robust. The shape of the hockey stick does not depend upon the bristlecone pine. Even though that’s what M&M and Wegman said, this is false.

    21) They can express all the lack of confidence they want. This is not any proof of anything other than their belief.

    22) Yet, despite all this “undertainty” there are scads of denialists CERTAIN that the MWP was warmer than today. Plus if the older data is so unreliable, why did you say older data was “proof” of fraudulent reporting in #4?

    23) You assert this but many subsequent analysis (as well as the blind test done mentioned above), with and without bristlecone data and extending even further have proven the hockey stick shape and proven that the current period (since the report in 98) is definitely warmer than the MWP.

    24) The data available from the decade-and-a-half has shown that the current period is definitely warmer. If you have any data to show a MWP in the south feel free to let people have it.