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Best Article I have read about IPCC


Merc14

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I love this article and it is wonderful being proved right. Frauds thieves and scoundrels have cost us billions of dolaars.

http://blogs.telegraph.co.uk/news/jamesdelingpole/100238047/global-warming-believers-are-feeling-the-heat/

Global warming believers are feeling the heat

From Thursday's Daily Telegraph

On Friday the Intergovernmental Panel on Climate Change delivers its latest verdict on the state of man-made global warming. Though the details are a secret, one thing is clear: the version of events you will see and hear in much of the media, especially from partis pris organisations like the BBC, will be the opposite of what the IPCC’s Fifth Assessment Report actually says.

Already we have had a taste of the nonsense to come: a pre-announcement to the effect that “climate scientists” are now “95 per cent certain” that humans are to blame for climate change; an evidence-free declaration by the economist who wrote the discredited Stern Report that the computer models cited by the IPCC “substantially underestimate” the scale of the problem; a statement by the panel’s chairman, Dr Rajendra Pachauri, that “the scientific evidence of… climate change has strengthened year after year”.

As an exercise in bravura spin, these claims are up there with Churchill’s attempts to reinvent the British Expeditionary Force’s humiliating r

retreat from Dunkirk as a victory. In truth, though, the new report offers scant consolation to those many alarmists whose careers depend on talking up the threat. It says not that they are winning the war to persuade the world of the case for catastrophic anthropogenic climate change – but that the battle is all but lost.

At the heart of the problem lie the computer models which, for 25 years, have formed the basis for the IPCC’s scaremongering: they predicted runaway global warming, when the real rise in temperatures has been much more modest. So modest, indeed, that it has fallen outside the lowest parameters of the IPCC’s prediction range. The computer models, in short, are bunk.

More here http://blogs.telegraph.co.uk/news/jamesdelingpole/100238047/global-warming-believers-are-feeling-the-heat/

Hey, if they really cared about mankind's future on this planet they'd be happy warming has all but ended but the fact they are so incredibly angry means this is about far more than a scientific theory.

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I've heard human CO2 production is 15-25% of what volcanoes produce, or was in 2000 or so. And IPCC stance does seem to open a lot of opportunities for money-making for people: tax all the CO2, lawsuits, green this green that, legistlations, paperworks. Though same could be said about any pre-emptive agency, like those that control our foods dont contain too much mercury and like that. But if they dont do their job, they usually revise their thinking right?

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The new thinking is that the Oceans are slowing things down. Which, of course, they did not expect back 20+ years ago. So, my question is... If they did not have a clue about the oceans eating up vast amounts of heat (supposedly), then why should we trust that they actually are correct NOW? Sure they have models and expectations, but what if the land soaks up some of the heat, or plants thrive and ruin CO2 expectations? It seems to me that they are merely putting out a "Best Guess" which is really just that, an educated guess...

I look forward the Report.

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Though the details are a secret, one thing is clear: the version of events you will see and hear in much of the media, especially from partis pris organisations like the BBC, will be the opposite of what the IPCC’s Fifth Assessment Report actually says.

That's why you need to read the report yourself. The Telegraph is writing op-eds based on a report it hasn't even seen yet. Read the assessment and make up your own mind.

A few things to keep in mind: IPCC references scientific studies, but is not itself, a scientific study. There has been some massaging of the science. In general, it's fairly accurate, but there are some things that make you wonder. If you want to know the truth, you need to go back to the original studies and read them carefully. Depending on some journalist's summary of a massaged report that he didn't understand is a good way to end up with the wrong conclusions.

Public pronouncements by scientists are usually very conservative. Nobody wants to release something he can't back up. Besides being embarrassing to be proven wrong, it can damage your career. For that reason, IPCC's estimates, which are based on conservative estimates, will probably be conservative themselves.

In 1991, IPCC released some projections that sounded pretty far-out. Since then, they have become more conservative. Until now. The pendulum is moving back the other way. One can see this a lot in science. The first guy finds something at odds with the status quo. He publishes a number that is out there quite a ways, but not far enough to get him thrown out of the room. The next guy finds the same thing, then publishes a number a little farther out. And so on. Eventually somebody overshoots the mark and the numbers start to come back in. Eventually, science zeroes in on the correct result. Looks like that's what we're doing with the IPCC's future estimates.

BTW, Merc: when are you going to post those examples of sculduggery you keep harping on?

Doug

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That's why you need to read the report yourself. The Telegraph is writing op-eds based on a report it hasn't even seen yet. Read the assessment and make up your own mind.

A few things to keep in mind: IPCC references scientific studies, but is not itself, a scientific study. There has been some massaging of the science. In general, it's fairly accurate, but there are some things that make you wonder. If you want to know the truth, you need to go back to the original studies and read them carefully. Depending on some journalist's summary of a massaged report that he didn't understand is a good way to end up with the wrong conclusions.

Public pronouncements by scientists are usually very conservative. Nobody wants to release something he can't back up. Besides being embarrassing to be proven wrong, it can damage your career. For that reason, IPCC's estimates, which are based on conservative estimates, will probably be conservative themselves.

In 1991, IPCC released some projections that sounded pretty far-out. Since then, they have become more conservative. Until now. The pendulum is moving back the other way. One can see this a lot in science. The first guy finds something at odds with the status quo. He publishes a number that is out there quite a ways, but not far enough to get him thrown out of the room. The next guy finds the same thing, then publishes a number a little farther out. And so on. Eventually somebody overshoots the mark and the numbers start to come back in. Eventually, science zeroes in on the correct result. Looks like that's what we're doing with the IPCC's future estimates.

BTW, Merc: when are you going to post those examples of sculduggery you keep harping on?

Doug

Read all you can on climatgate and the hockey stick. Watch Al Gore shill his movie to schoolkids. Watch the MSM that pushes this tripe and ignores all else. Know when someone is p***ing down your leg and telling you it is raining.

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Read all you can on climatgate and the hockey stick. Watch Al Gore shill his movie to schoolkids. Watch the MSM that pushes this tripe and ignores all else. Know when someone is p***ing down your leg and telling you it is raining.

I have Mann et al.'s original articles on "the hockey stidk" as well as Wegman's, McIntyre's and McKittrick's critiques. I also have the rebuttals to the rebuttals and, because the original paper dealt extensively with dendrochronology, I have reviewed them all myself. Though I have some criticisms of Mann, most of my criticisms are of Wegman, McIntyre and McKittrick. Wegman and McIntyre, for not understanding what was being done before sounding off and McKittrick for trying to slant the discussion with irrelevant issues.

My criticism of Mann: some of the data was in-filled. The COFECHA program does this automatically and its use may have been nothing more than an oversight. At any rate, if you have plenty of corroborating data, an in-fill should be pretty close to the real value. But if you have plenty of data, you don't need to do any infilling. I would not have used in-filled data (Neither would Wegman, McIntyre or McKittrick; that criticism is valid.). On the other hand, I can't see that its use distorted the findings in any way.

This is an observation, not a criticism: Mann deleted small chronologies because of their high variance. This will "sharpen the focus" of the dataset, making the remaining chronologies clearer. It's a valid method because it does not bias the resulting curve (unless the resulting curve is based on too few chronologies). Mann used plenty of chronologies (several hundred) - no problem there. The fact that some chronologies were dropped led to spurious charges of "cherry-picking" the data. Mann could easily have avoided this by simply not telling anybody what he had done, but he followed the standard practice of putting everything out there. In science this is done so that everything is out in the open where it can be seen and evaluated. If somebody doesn't like what you've done, that's their problem; they can rerun the experiment their own way. Then, if they find something different, there is something to discuss. The deniers have never repeated Mann's work - I suspect because it's a lot of work and they're afraid they'll just end up confirming Mann's findings.

The "hockey stick controversy" stems from the difference between Mann's temperature reconstruction (which applies to northern Europe) and Lamb's free-hand reconstruction (which applies to England). Lamb showed a pronounced high-temperature period (the Medieval Warm Period), from which temperatures declined into the early 1900s, following which we have seen a meteoric rise in global temps. That's important to the deniers because it would show a recent warm period and that would imply that the temperature rise could be natural (meaning mitigation is unnecessary). Mann's reconstruction showed temperatures relatively flat for the last 1400 years, ending with the rise beginning about 1907. That would suggest that the temperature rise is the result of industrial activity (making remediation desirable). What neither side can seem to understand is that Lamb's free-hand "graph" and Mann's reconstruction apply to TWO DIFFERENT AREAS. They are trying to compare apples and oranges! NEITHER are representative of GLOBAL conditions.

As I write this, there has not been a GLOBAL temperature reconstruction covering the past 1400 years. There have been a number of articles theorizing on how this might be accomplished, but so far, it hasn't been done. The major problem is that different regions respond differently. You need a process that can handle temps going up in one area and down in another. Theoretically that's possible, but actually doing it would be a monumental task.

About Wegman: he is a statistician, not a dendrochronologist. his chief complaint deals with the statistics. Tree ring data has the problem of wide, highly-variable rings early in the tree's life. As the tree grows, the rings get narrower and the variance decreases. This violates one of the assumptions of modeling: that variance is uniform throughout the range of the dataset (It's called: homoscedasticity - how's that for a fifty-cent word?). One can solve the problem by use of the "Box-Cox Transform," a process that produces a dataset with uniform variance from one that lacks it. Unfortunately that process produces some negative values, even when the average Y' value is added back in the reconstitutional phase.

In the next step, the dataset would be detrended to remove the age effect. The most-common model is the negative logarithm (not very accurate during the first few years of a tree's life, but pretty good most of the time). But that's exponential, so when the computer tries to take a log of a negative number (sort of like dividing by zero), the process "blows up." There are three solutions to this problem: (1) use an inverse model (not very accurate), (2) use a regionally standardized growth curve (not always available and a lot of work to create, especially if you have to make one for each of several hundred chronologies) and (3) "cheat" (use the negative logarithm without going through the Box-Cox Transform first).

There are no other usable models. Most models have the nasty habit of removing the temperature signal along with the age signal (That includes the famous "Hugershoff's Model"). That's even a problem for the negative logarithm in some trees.

Mathematically "cheating" works, but you can't be sure that you aren't introducing a bias into the dataset. And that is the basis of Wegman's complaint. There is a risk, however small, that the system didn't work.

So how do we solve this problem? Regionally standardized curves. Over 400 of them. It's gonna take a major grant, but if you want accuracy, you have to do the ground work. AND: regionally standardized curves don't work very well with small datasets. This will require the elimination of extremely small chronologies - here we go with the "cherry-picking" argument again.

I'll have to get to the ins and outs of regionally standardized curves some other time, as I will with McKittrick and McIntyre.

About Al Gore and his PowerPoint: he isn't a climatologist, either. He had a good layman's understanding of things back in the 1990s, but he's a little out of date, now (as are attempts to discredit climate science by referring to him). I find it strange that deniers have so much trouble finding CURRENT studies to criticize that they have to keep bringing up long-transcended (or obsolete) ideas (like 30-year old climate models). Anyway, when you look closely at his presentation, he didn't say all that much - "it's getting warmer!" - anybody with a record of temps can see that. Tell us something we don't know.

I submit that you are getting a biased picture of climate science because of your choice of sources and an unwillingness to check the "facts" they are hyping. Had you done that, you would have known that wind power is cheaper than all other sources (except two natural gas processes) and saved yourself that embarrassing debacle on the other thread.

And I'm still waiting for you to post a reference that actually shows that skullduggery that you're talking about. Don't just repeat a good rumor you heard - dig up something by somebody who has actually investigated it.

Doug

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CHAIRMAN BARTON: Dr. North, do you dispute the conclusions or the methodology of Dr. Wegman’s report?

DR. NORTH [Head of the National Academy of Science panel]: No, we don’t. We don’t disagree with their criticism. In fact, pretty much the same thing is said in our report.

DR. BLOOMFIELD [Head of the Royal Statistical Society]: Our committee reviewed the methodology used by Dr. Mann and his co-workers and we felt that some of the choices they made were inappropriate. We had much the same misgivings about his work that was documented at much greater length by Dr. Wegman.

WALLACE [of the American Statistical Association]: ‘the two reports [Wegman's and NAS] were complementary, and to the extent that they overlapped, the conclusions were quite consistent.’

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Thanks for that post. It pretty much says what I just did, without going into detail.

CHAIRMAN BARTON: Dr. North, do you dispute the conclusions or the methodology of Dr. Wegman’s report?

DR. NORTH [Head of the National Academy of Science panel]: No, we don’t. We don’t disagree with their criticism. In fact, pretty much the same thing is said in our report.

Wegman didn't like the use of datasets with non-uniform variance. It's a valid point, especially if you're a statistical purist, as is Wegman. And, as I said above, if you use datasets with non-uniform variance, you can't guarantee the result. Mann did not correct for the lack of homoscedasticity and, statistically, that is a shortcoming of his study. He didn't do that because he did not have enough regionally standardized curves to compare with his chronologies. And, as I also pointed out above, I can't see that there was any bias in the results.

DR. BLOOMFIELD [Head of the Royal Statistical Society]: Our committee reviewed the methodology used by Dr. Mann and his co-workers and we felt that some of the choices they made were inappropriate. We had much the same misgivings about his work that was documented at much greater length by Dr. Wegman.

WALLACE [of the American Statistical Association]: ‘the two reports [Wegman's and NAS] were complementary, and to the extent that they overlapped, the conclusions were quite consistent.’

Also, as I pointed out, the way to correct for the problem is to re-do the study using RCS. But nobody has done that. So while there is no way to guarantee the accuracy of Mann's study, neither is there any way to say that he is wrong. So how about it deniers? Why don't you get off your rear ends and do the work?

Speaking personally, I'd love the opportunity to do just that. I think the results would by-and-large confirm Mann's reconstruction. The only problem: when done, it still only applies to northern Europe.

Doug

P.S. for Merc and Little Fish: why have you not brought up the problem of the lack of homoscedasticity before? For that matter, why didn't anybody else, including Wegman, McIntyre and McKittrick? Only after I tried to run my own analysis of another dataset did I figure out why it wasn't working. That's when I went back and reread the reports and figured out what they were really saying.

It doesn't do anybody any good to rant about dishonesty if you then can't say what it was they did. That's the situation with WMM. They never said what it was that was bothering them. Mann's analysis was not dishonest. Its real problem was that it didn't take all the statistics into account. That's a technical error, not a problem of integrity. Wegman et al. never charged anybody with dishonesty. They only said they'd do it differently. And on that, I can agree.

The problem now is one of your own integrity. You have claimed, on the basis of somebody else's misinterpretation of Mann, Wegman et al. that dishonesty was involved. Not only can you not support that claim, you can't even point to the person you got it from. If you repeat somebody else's lie, it becomes your lie. And that's where we stand.

Doug

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Doug's insists that Climaetgate didn't involve dishonesty, subterfuge, prejudice and plain old manipulation of data . Doug isn't a good witness any longer because, despite his education, he can't see that the scientific process was compromised. Doug is a zealot. Creationist think the world is 6000 years old and refuse to consider anything that refutes their tightly held beliefs. Parallels?

Doug, tree rings, from one specific place on one continent, can't decipher the code that is beyond human knowledge at this time. I respect your knowledge but not your refusal tp admit that all may not be as it seems. I am not a scientist but I deal with many of them and sometimes they can't see the forest for the trees. Pun intended sir.

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The Wegman report (endorsed by the National Academy of Sciences) confirmed the criticisms of McKitrick and McIntyre.

For Doug, the wegman report was just pointing out a few trivial improvements.

what doug is not saying is that when random data was fed into Mann's algorithm, it produced hockey stick charts.

This is the view of the Wegman report and NAS. No mention from Doug of Mann's dominant proxy, the bristlecone pines, I don't think Doug understands why Mann's Hokey Schtick is blx.

Mann has the audacity to claim the NAS vindicated his study, and cornelieus just repeats it. there's no integrity in climate science.

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Doug's insists that Climaetgate didn't involve dishonesty, subterfuge, prejudice and plain old manipulation of data .

Did I mention Climategate? Apparently you can't read too well, or my memory is going, because I don't remember doing it. But, if I have the time tomorrow or sometime next week, I'll look into it, seeing as you are unable to do that for yourself.

Doug isn't a good witness any longer because, despite his education, he can't see that the scientific process was compromised. Doug is a zealot. Creationist think the world is 6000 years old and refuse to consider anything that refutes their tightly held beliefs. Parallels?

I will change my stance on global warming any time anybody can present some evidence. As a matter of fact, I change something about it almost every day. New research comes out and I read it. Things are always changing. But the bottom line: global temps are rising, primarily as a result of human-caused carbon pollution of the atmosphere, has not changed in a long time. ALL the arguments are about how much it is changing or how important this or that variable is, or what the exact relationship between two variables is. But not global warming, itself. That's clearly established.

Doug, tree rings, from one specific place on one continent, can't decipher the code that is beyond human knowledge at this time. I respect your knowledge but not your refusal tp admit that all may not be as it seems. I am not a scientist but I deal with many of them and sometimes they can't see the forest for the trees. Pun intended sir.

My collections come from Ohio, Colorado, Arkansas and Oklahoma. I have access to a world-wide database, as do you, if you would care to use it. Mostly, I study storm records in tree rings, but I also study the effects of those storms on timber production. I also study tree ring chronologies from all over the world: that's why I am familiar with Mann's work. I have done some small-scale climate studies locally, but nothing as dramatic as Mann's.

I suspect the reason you aren't communicating with the scientific community is that you unknowingly make beginner mistakes that give you away. You won't get a hearing if they don't think you know what you're talking about. First and foremost, that means being familiar with current research in the field. If you can make a well-informed critique of it, you will have a much-better chance of getting scientists to listen.

Doug

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The Wegman report (endorsed by the National Academy of Sciences) confirmed the criticisms of McKitrick and McIntyre.

For Doug, the wegman report was just pointing out a few trivial improvements.

Actually, Mann took some standard shortcuts that maybe dendrochronology should not be so ready to use. That's a valid criticism of the profession as a whole, not just Mann. But we realize what those are, that they may cause problems and we try to minimize their effects and our work is subject to that caveat. But some studies go the whole nine yards and do all of it according to the rules. That's what I'd like to do with Mann's study - redo it without the shortcuts. Who knows? Maybe I can get a grant. But I think events are beyond that point, now. In the 14 years since publication, there has been a lot more work done. New chronologies are getting posted at the rate of two or three a week. I'm wondering why you deniers don't critique some of the newer stuff if you don't think it's accurate?

Also, as I mentioned above, sometimes you just have to do something, explain what it was and why and let those who don't like it, do their own study. That's where you guys were ten years ago: if you doubt Mann's study, repeat it yourself, or do your own study. That's what science is: checking the other guy's work to make sure he got it right.

what doug is not saying is that when random data was fed into Mann's algorithm, it produced hockey stick charts.

As I recall, the data used was NOT random, but my memory is a little foggy on that. I'll have to check and get back to you on it. Would you mind posting where you found that? It could save some time.

This is the view of the Wegman report and NAS. No mention from Doug of Mann's dominant proxy, the bristlecone pines, I don't think Doug understands why Mann's Hokey Schtick is blx.

I have printouts of both the Methuselah Walk and White Mountain Two chronologies. They are from California, so I'm wondering why you think they would be used in an analysis that pertains to northern Europe. Are we talking about the same papers?

Mann has the audacity to claim the NAS vindicated his study, and cornelieus just repeats it. there's no integrity in climate science.

THAT is something that CAN be checked. It will take a few days, as I have other stuff that needs to get done. Maybe next week.

Doug

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As I recall, the data used was NOT random, but my memory is a little foggy on that.

Well, I guess my memory WAS a little foggy on that. What McIntyre/McKittrick used was a Monte Carlo test. When you don't know what the confidence limits of a technique will be, you can run thousands, even millions, of tests of the system using random numbers. The distribution of the outcomes is probably pretty close to the distribution of the model. This works as long as the random numbers used have the same distribution as real-life data would (Random numbers have a random distribution, but that can be modified in any number of ways to simiulate various other distributions.). If that condition isn't met, the results may not be right. I have so far not found whether McIntyre/McKittrick did this. I'll keep looking.

I also said that nobody had done a GLOBAL study. That's true, as far as it goes, but Roseanne D'Arrigo did one of the Northern Hemisphere in 2006 that confirmed the Medieval Warm Period. So now it's time to take a closer look at Mann's reconstruction and see just how much of a decrease he found. It's also time to see if northern Europe is different from other places and how much. I'm suspicious that we're still trying to compare apples and oranges.

And I was thinking of a different study when I said he used 400 chronologies - he only used 70.

McIntyre/McKittrick criticised Mann for an improper use of Principal Components Analysis. I have never attempted that. I will have to check it out. Also, it isn't needed for local climate studies. I'm wondering why it was used at all.

Doug

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DR. NORTH [Head of the National Academy of Science panel]: No, we don’t. We don’t disagree with their criticism. In fact, pretty much the same thing is said in our report.

I will repeat it here, you are cherry picking Dr Norths quote,and you know you are, he concludes that the issues raised have no overall effect on the shape of the hockey stick.

For you to repeatedly selectively misquote Dr North in this way shows that you are dishonest. How you can change the conclusion of a commentator when you know it to be untrue is frankly beyond me.

Br Cornelius

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I will repeat it here, you are cherry picking Dr Norths quote,and you know you are, he concludes that the issues raised have no overall effect on the shape of the hockey stick.

For you to repeatedly selectively misquote Dr North in this way shows that you are dishonest. How you can change the conclusion of a commentator when you know it to be untrue is frankly beyond me.

Br Cornelius

i am not aware of any fuller quote. I note that you don't show what you assert.

seems pretty clear to me:

question - "do you dispute the conclusions or the methodology of Dr. Wegman’s report?"

"We don’t disagree with their <wegman / mcIntyre / Mckitrick> criticism. In fact, pretty much the same thing is said in our report." - National academy of science

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i am not aware of any fuller quote. I note that you don't show what you assert.

seems pretty clear to me:

question - "do you dispute the conclusions or the methodology of Dr. Wegman’s report?"

"We don’t disagree with their <wegman / mcIntyre / Mckitrick> criticism. In fact, pretty much the same thing is said in our report." - National academy of science

Your memory is very selective since I have given it to you previously. If you insist I can spend a bit of time finding the quote again, but it would be better for you if you just admitted your mistake now.

The point the Doctor made was that he accepted that there were errors in the choice of statistical analysis (though that was mainly a subjective conclusion) - but that he did not find that they made any difference to the shape of the graph or the conclusions of Manns paper. He accepted that Manns analysis was a true reflection of the data he analysed.

Its really very simple, the Wegman report found some minor errors which make no difference to the final outcome and Dr North is in agreement with Michelle Mann whilst acknowledging that errors exist. Since that time Michelle mann has produced an updated analysis which takes account of the points raised - and still produces the same result - which again supports Dr Norths conclusion that the graph is a true reflection of the temperature record.

Br Cornelius

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...but my memory is a little foggy on that.

I guess so. This topic has become a bit of a train wreck and I am mostly to blame. It has been several years since I read most of this stuff and my memory let me down. I have confused several VERY important points.

Mann wrote THREE papers. So, yes, we were talking about different papers. The first was the "hockey stick" paper (Mann et al. 1998). The essence of the "controversy" is whether the Medieval Warm Period was warmer than present (defined as the year 2000). Deniers need current temps to be below the MWP high to support their claim that current temps are nothing unusual. Proponents need the opposite. The MWP lasted from about 900 AD to about 1300 AD. But Mann's paper covered the interval from 1400 AD to the present. The two intervals do not even overlap; thus, this paper is pretty much irrelevant to the "controversy." But because nobody (denier or proponent) seems inclined to actually read what was written, both sides assumed Mann was claiming the MWP barely existed. This study was the first use of a new technique based on eigenvectors. The paper included the famous “hockey stick” graph.

The following year the same authors extended the study back to 1000 AD using the same techniques (Mann et al. 1999). This now included three-quarters of the Medieval Warm Period. The paper included a string of caveats, among them that uncertainties prevented decisive conclusions before the year 1400. But the popular press doesn’t find caveats interesting, so none of this got reported in the mass media.

Mann published a third paper which contained eight climate reconstructions from North and South America, Scandinavia, the subtropical North Atlantic, western Greenland, central England, eastern China and the Andes (Mann 2002). This paper points out the localized temperature regimes present during the MWP. The (averaged) Northern Hemisphere reconstruction and the western North America reconstruction (those bristlecones) barely show a warm period, while most of the rest of the world clearly had warmer temps. West Greenland and the tropical Andes started the MWP with a sharp drop in temps, then followed up with a sharp rise. Central England got off to a slow start, but later caught up.

The first two papers were controversial mostly because they were used by the IPCC in support of the 2001 Third Assessment Report. The third one came out too late for the IPCC to use, so did not attract as much scrutiny from the general public. Mann’s paper was one of four cited by the IPCC in support of its conclusions.

Experts disputing the findings included Pat Michaels of the fossil-fuel funded George C. Marshall Institute and Fred Singer who has questioned the link between melanoma and UV-B, the link between CFCs and the ozone hole and the risks of passive smoking. Michaels actually is a climatologist and Singer is an atmospheric physicist. These two men are among a tiny minority of scientists who question global warming and have the expertise to actually understand it.

A paper claiming greater Medieval warming (Soon and Baliunas 2003) was used by the Bush Administration in its attack on the Environmental Protection Agency and to justify non-support of the Kyoto protocols (which I thought was a good idea at the time). The publication led to concerns about the peer review process and the resignations of several editors. The journal subsequently withdrew it from publication, but Jim Inhofe (Oklahoma’s great embarrassment) spoke in the Senate, citing it in support of his claim that “man-made global warming is the greatest hoax ever perpetrated on the American people.” When my wife pressed him to support that claim, he sent her an email explaining that he had to say those things to keep getting elected – he had nothing to support it.

The George C. Marshall Institute and the Competitive Enterprise Institute publicized a paper (McIntyre and McKitrick 2003) without going through peer review critical of Mann’s proxy data and methods. McIntyre is a mathematician, former minerals prospector and semi-retired mining consultant and the founder/editor of Climate Audit, a blog. He doesn’t have any other qualifications. McKitrick is an economist specializing in environmental economics and policy analysis. This popular-press paper was his first foray into climate; though, he has since published others, mostly to defend this one.

Hans von Storch et al. (2004) criticized Mann’s statistics as underestimating variation in the earlier part of the reconstruction. This was disputed and he later acknowledged that the effect was small.

McKitrick and McIntyre tried again in 2005 with a critique of Mann’s Principal Components Analysis, a technique used when there are multiple series, each trending in different directions. This was disputed by Huybers (2005) and Wahl and Ammann (2007) who pointed out mistakes in McIntyre’s and McKitrick’s papers.

At the request of Sherwood Boehlert, Chairman of the House Science Committee, a panel of scientists was convened by the National Research Council (North 2006). This is the report to which Little Fish has been referring. It supported Mann’s findings with some qualifications, agreeing that there were some statistical shortcomings, but concluding that they had little effect on the result. Little Fish’s excerpts misrepresent what is in the report. The citation is below. Read it and make up your own mind.

Representative Whitfield and Edward Wegman (Wegman 2006) set up a committee of statisticians to investigate. They supported McIntyre and McKitrick that there were statistical shortcomings, but did not determine whether these had affected the results. They also produced a network analysis which has since been discredited by others amid charges of plagiarism (Mashey 2011; Mashey 2012).

The Climate Research Unit email controversy (“Climategate”) resulted from the hacking (theft) of private emails from a server at East Anglia University in 2009. These were released out of context and selected to be as embarrassing as possible to the legitimate owners. Eight different independent investigations (which I don’t have a list of; how about it Br. Cornelius – do you have a list of these?) subsequently cleared the scientists of all wrongdoing charges.

Since 1998 there have been at least two dozen reconstructions using different methods, so Mann’s findings have been tested many times. Fourteen of these were used by the 2007 Fourth Assessment Report in support of its findings. All these reconstructions have come out intermediate between Lamb’s original free-hand drawing and Mann’s (1998) reconstruction, but being closer to Mann than to Lamb. I apologize for forgetting this.

The only examples of skullduggery I found in connection with the Hockey Stick and Climategate scandals were those of Wegman who produced an erroneous analysis, significant parts of which he plagiarized (stole) from other authors with minor manipulation and with the Climategate hackers and their supporters who stole private correspondence and deliberately misrepresented what it said.

Mann, Bradley, Hughes, McIntyre and McKitrick all had honest differences of opinion stemming from technical mistakes in their investigations.

Below is a bibliography which I will enlarge if I can get ahold of the Climategate investigation reports. It will take some time to dig up the newer climate reconstructions and I doubt if I can even find all of them. I’ll post them when I find them.

In the meantime, all three of us (Merc, Little Fish and myself) deserve an “F” grade for our poor scholarship.

Doug

Huybers, P. 2005. Comment on “Hockey sticks, principal components, and spurious significance” by S. McIntyre and R. McKitrick. Geophysical Research Letters 32, L20705.

Mann, M. E., R. S. Bradley and M. K. Hughes. 1998. Global-scale temperature patterns and climate forcing over the last six centuries. Nature 392:779-787.

Mann, M. E., R. S. Bradley and M. K. Hughes. 1999. Northern hemisphere temperatures during the past millennium: inferences, uncertainties, and limitations. Geophysical Research Letters 26(6) (1999): 759-762.

Mann, M. E. 2002. The earth system: physical and chemical dimensions of global environmental change. In: MacCracken, M. C. and J. S. Perry, eds., encyclopedia of global environmental change. John Wiley and Sons, Chichester.

Mashey, J. R. 2011. Strange problems in the Wegman report, special report 35.2. Committee for Skeptical Inquiry.

Mashey, J. R. 2012. See no evil, speak little truth, break rules, blame others. http://23.21.253.212/sites/beta.desmogblog.com/files/see.no_evil_.speak_little.truth_.pdf.

McIntyre, S. and R. McKitrick. 2003. Corrections to the Mann et al. (1998) proxy data base and northern hemispheric average temperature series. Multi-Science Publishing Co., Essex, UK.

McIntyre, S. and R. McKitrick. 2005. Hockey sticks, principal components, and spurious significance. Geophysical Research Letters 32(3).

North, G. R. 2006. Surface temperature reconstructions of the last 2,000 years. In: Statement of Gerald R. North, Ph.D., Chairman on Surface Temperature Reconstructions of the last 2,000 years, National Research Council, National Academy of Sciences.

Soon, W. and S. Baliunas. 2003. Proxy climatic and environmental changes of the past 1000 years. Climate Research 23:89-110.

Von Storch, H., E. Zorita, J. M. Jones, Y. Dimitriev, F. Gonzales-Rouco and S. F. B. Tett. 2004. Reconstructing past climate from noisy data. Science 306(5696):679-682.

Wahl, E. R. and C. M. Ammann. 2007. Robustness of the Mann, Bradley, Hughes reconstruction of Northern Hemisphere surface temperatures: examination of criticisms based on the nature and processing of proxy climate evidence. Climatic Change 85:33-69.

Wegman, E. J. 2006. Ad hoc committee report on the “hockey Stick” global climate reconstruction, commissioned by the US Congress House Committee on Energy and the Envrionment. US House of Representatives.

Edited by Doug1029
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I love these threads.

Doug and Cornelius win again.

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they win the award for obfuscation.

I can see you didn't take my suggestion about actually reading the report. In case you can't find it, it is available here:

http://www7.nationalacademies.org/ocga/testimony/Surface_Temperature_Reconstructions.asp

This is a direct quote from that report:

"The basic conclusion of the 1999 paper by Dr. Mann and his colleagues was that the late 20th century warmth in the Northern Hemisphere was unprecedented during at least the last 1,000 years. This conclusion has subsequently been supported by an array of evidence that includes both additional large-scale surface temperature reconstructions and pronounced changes in a variety of local proxy indicators, such as melting on icecaps and the retreat of glaciers around the world, which in many cases appear to be unprecedented during at least the last 2,000 years." --Gerald R. North

The document Little Fish has been excerpting is to be found here:

http://www.nap.edu/catalog.php?record_id=11676

As the National Academy Press charges for its products ($40.00, in this case), I'm willing to bet that Little Fish doesn't own a copy and has never read it and that her quotes actually come from denialist websites.

Little Fish: I'm sorry if you find my explanations confusing. In science, the objective is to track down every detail, every nuance. And that can be complicated. I suspect you would be happier in a less-demanding line of work.

Doug

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