Debunking The Left's War On Science (1 Viewer)

[aquapub]

Two Canadian experts, Stephen McIntyre and Ross McKitrick (known as "M&M" in discussions of the climate debate), found enormous flaws in the hockey stick figures being trotted out by the Left to scare people into unreasonable anti-corporate regulations.

http://www.nationalreview.com/comment/murray200311030813.asp
http://www.climateaudit.org/
http://www.uoguelph.ca/~rmckitri/research/trc.html


Before you go confirming my observation that when the Left is confronted by science that doesn't conform to what they want to be true, they dissmiss or undermine it without actually intellectually confronting the assertions its based on (and this tendency does NOT stop with science), you might want to at least try to form some kind of intelligible refutation.

In short, no one is interested in your usual defensive smear tactics.

 

[hipsterdufus]

Two Canadian experts, Stephen McIntyre and Ross McKitrick (known as "M&M" in discussions of the climate debate), found enormous flaws in the hockey stick figures being trotted out by the Left to scare people into unreasonable anti-corporate regulations.

http://www.nationalreview.com/comment/murray200311030813.asp
http://www.climateaudit.org/
http://www.uoguelph.ca/~rmckitri/research/trc.html

Before you go confirming my observation that when the Left is confronted by science that doesn't conform to what they want to be true, they dissmiss or undermine it without actually intellectually confronting the assertions its based on (and this tendency does NOT stop with science), you might want to at least try to form some kind of intelligible refutation.

In short, no one is interested in your usual defensive smear tactics.

Talk about a War on Science: This study by M&M wouldn't hold up in a High School Biology class.

"So the facts deal a death blow to yet another false claim by McIntyre and McKitrick. Despite the plain facts, as layed out here, however, their false claims have nonetheless been parotted in op-ed pieces of dubious origin and other non-peer-reviewed venues."

Michael Mann

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Stephen McIntyre and Ross McKitrick have become famous (or infamous) for claiming to have found major problems with a recent reconstruction of the past climate (called the Hockey Stick because of the shape). Even though major and glaring errors have been found in their writings, they continue to be favorites with the global warming "skeptics."

http://info-pollution.com/mandm.htm

In a previous post, we discussed a number of examples where the "Peer Review" process has failed, and poor papers have been published in the ostensibly peer-reviewed literature. In this context, we revisit our previous discussions of the flawed work of McIntyre and McKitrick (henceforth "MM"). MM published a paper, in the controversial journal Energy and Environment, claiming to "correct" the proxy-based reconstruction of Northern Hemisphere temperatures published by Mann et al (1998--henceforth "MBH98"). Following the all-too-familiar pattern, this deeply flawed paper was heavily promoted by special interests as somehow challenging the scientific consensus that humans are altering the climate (an excellent account is provided by science journalist Dan Vergano of USA Today here). As detailed already on the pages of RealClimate, this so-called 'correction' was nothing more than a botched application of the MBH98 procedure, where the authors (MM) removed 80% of the proxy data actually used by MBH98 during the 15th century period (failing in the process to produce a reconstruction that passes standard "verification" procedures--an error that is oddly similar to that noted by Benestad (2004) with regard to another recent McKitrick paper). Indeed, the bizarre resulting claim by MM of anomalous 15th century warmth (which falls within the heart of the "Little Ice Age") is at odds with not only the MBH98 reconstruction, but, in fact the roughly dozen other estimates now published that agree with MBH98 within estimated uncertainties.


All of their original claims have now been fully discredited (see e.g. this previous post as well as this discussion of a paper 'in press' in the Journal of Climate by Rutherford et al). MM however, continue to promote false and specious claims. McIntyre and McKitrick (2005), in a paper they have managed to slip through the imperfect peer-review filter of GRL, now simply recycle the very same false claims made by them previously in their comment on MBH98 that was rejected by Nature.

http://www.realclimate.org/index.php?p=111

 

[pendulum_jaw]

This is an important controversial topic, but in my opinion this type of "he-said, she-said" debating is not very strong, and certainly uninteresting. The OP posted a few references that shine the light of criticism on the research of Dr. Michael Mann. Dr. Mann is the author of the 1998 paper concluding that global temperature of the twentieth century was the hottest of any other period in the last 1000 years--the same paper containing the well-known "hockey-stick" temperature graph. This paper is important because it is virtually the sole foundatoin for the IPCC-sponsered notion that man-made activity is responsible for 'global warming'. The OP cited several ongoing studies by two researchers--Stephen McIntyre and Ross McKitrick--who have published several papers critiquing the conclusions of the MAN98 study. Hipsterdufus responded to the post by quoting Dr. Mann's website where he essentially claims "I'm right and they're wrong." The response does not cite specific replies to specific criticisms of the paper, but then again the OP (aquapub) did not illuminate specific criticisms to the MAN98 paper (and there are many). I think the better strategy for a debate forum is to choose specific points from your references and put forth an argument of your understanding of what they mean in the context of the issue. In short, one must try to make a convincing argument. Anybody can cut and paste things into their web browser.

That said, I will use this opportunity to point out that the National Academies of Sciences' Board on Atmospheric Sciences and Climate just released their much-anticipated report [Surface Temperature Reconstructions for the Last 2,000 Years (2006)] aimed at analyzing the available evidence for the types of claims made in MAN98 and subsequent papers based on MAN98. The full report can be found here and if you're interested in my post you should at least read the 4-page summary.

I want to illuminate a specific phenomenon that is unfortunately a persistent and recurrent problem on such issues as global warming, genetically-modified organisms, pollution, medical technoligical research, etc. What scientific share in common is that although they are important to and debated about by the general public, the majority of the general public lacks the scientific expertise to be able to distinguish fact from fiction. Highly technical jargon, complex scientific methodologies, and scientific prestige of those advocating positions often substitutes for a basic, rational, nuts-and-bolts argument of one's position, and are used to 'wow' people into believing that because one sounds highly intelligent and seems to know what he is talking about, that his side is correct. This strategy has been largely successful on those who are massively ignorant about scientific issues. Thus my first point--and I think we can all agree on this--is that a certain degree of specialized, scientific knowledge is necessary for one to understand the issues involved in the debate over whether man-made temperate change is actually occurring or not. That said, I think we can further agree that anybody or any technique that serves to enhance the complexity of the debate--and thus confuse more people--is wholly antiproductive to the pursuit of truth.

Now I get to the problimatic phenomenon that I mentioned, and I believe it is an appropriate subject for this thread, although aquapub didn't explicitly acknowledge it. Simply stated, the world media as a whole has consistently misrepresented the findings of scientific research, and in doing so has failed in providing an accurate representation of scientific knowledge to the public at large. In at least some cases, it's difficult to believe that their distortion of results is anything but politically motivated--and whether one agrees with the side being favored in the report or not, one should not support distortions of facts being reported as real facts.

This brings me to the recently released NAS report on climate change referenced above. There are a couple main conclusions of the report, which has obviously been written to appease both sides of the debate alluded to by the OP. I'm going to give you the conclusions of the report, and then show you how major world news organizations misrepresented NAS findings.

Firstly, the report verifies the well-established fact that 'the 20th century was the warmest period in the last 400 years'. No scientist disputes this, including McIntyre/McKitrick, and there is no controversy over the data that establishes the record.

(from the NAS report)
"It can be said with a high level of confidence that global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries. This statement is justified by the consistency of the evidence from a wide variety of geographically diverse proxies."

The report agrees that this recent temperature increase is consistent with the notion of global climate recovery from what's known as the "Little Ice Age" which lasted between 1500-1850. In other words, there's no surprise that global temperatures increased after a scientifically supported minor 'ice age'. The report explicitly supports the notion that this minor 'ice age' is supported by the evidence. Similarly, the report notes that the available evidence also supports the existence of the "Medieval Warm Period", a period around 1000 of unusually hotter temperatures. The important point to draw from this acknowledgement is that Dr. Mann's temperature measurements in his 1998 do not show the "Little Ice Age" nor the "Medieval Warm Period", calling his historical record into question.

In line with the above, the report's 2nd major conclusion is the following:

(from the NAS report)
Based on the analyses presented in the original papers by Mann et al. and this newer supporting evidence, 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.
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. 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.


So while the committee states that it finds the MAN98 paper's conclusions 'plausible' (which carries zero weight, since almost anything can be considered plausible), it then states that 1) it has a 'high level of confidence' in the existence of the "Little Ice Age", which Mann's reconstruction got wrong; and 2) that it has "[e]ven less confidence...in the original conclusions by Mann...that 'the 1990s are likely the warmenst decade, and 1998 the warmenst year, in the last millennium."

Whether or not one agrees with the report, one must agree with what the report states here. It is sufficiently clear. Now let's look at how some of the major media organizations reported the NAS's analysis...

Headline from the CNN 'Science and Space' section:
" Study: Earth 'likely' hottest in 2,000 years"

Headline from the Associated Press (By John Heilprin)
"Report: Earth Hottest It's Been In 2,000 Years"

NBC Headline:
"Scientists: Earth Seeing Hottest Temperatures In 2,000 Years"

(post continued...)

 

[pendulum_jaw]

(...continued from above)

Headline from the Discovery Channel:
"Earth not this hot in hundreds, maybe thousands of years: experts"

Boston Globe headline (by Beth Daley):
"Scientists: Earth Seeing Hottest Temperatures In 2,000 Years"

Foxnews headline:
"Earth Hottest It's Been in 2,000 Years"

Here's an absolutely absurd headline from the Detroit Free Press (by John Heilprin)
"Earth warms to 2,000-year high"
Studies back evidence that human activities affect global warming and produce hurricanes."
(I challenge anyone to find evidence in the report supporting the notion that 'human activites affect global warming and produce hurricanes'. This is egregious bias.)

One gets the picture here. For any average non-expert who did not read the report, it would seem like the NAS supports Mann's conclusions. But a careful reading of the report reveals that is not the case. So why do news organizations get it wrong? An objective person must entertain the possibility that they are politically motivated, would you not agree? Or perhaps they are just collosally ignorant about how to understand a report summary? Whichever it is, we can all agree that such distortions certainly do not attempt to illuminate the truth of the matter; they only serve to distort and confuse.

A corollary point I'd like to make here, and the NAS report as well as how various media organizations interpreted it for their audience proves this to be the case, is that this is very much a controversial field. So many posters in this forum flat-out are posting comments demanding that the facts are in and there is no controversy--that there is general scientific consensus on the issue. This is so far from the truth that one really must question the objectivity of these people. One cannot will one's version of reality to be true. If one wishes to make the case, then attempt to do so with sources and reasoning; but don't try to cut off the debate by claiming that your point of view has already been established and that critics of it have already been addressed and silenced. Such posters have contempt for the scientific process, which requires the exact opposite: scientific progress depends on and flourishes precisely because scientists constantly question and attempt to disprove other scientists.

Lastly I would like to point out another fact of the record with respect to Dr. Mann. This his absolute obstinence and reticence to providing the scientific community with his data such that they could verify the analysis published in his 1998 paper. Why was this so? Reproducibility is a major pillar of the scientific process, yet this data was only dragged out of Dr. Mann by an act of the U.S. Congress. Any objective person should find that disturbing, given that the IPCC's reports are all primarily based on Dr. Mann's conclusions (reports whose aim is to impose significant costs on the U.S. economy in the name of preventing a problem that may or may not exist).

 

[hipsterdufus]

Lastly I would like to point out another fact of the record with respect to Dr. Mann. This his absolute obstinence and reticence to providing the scientific community with his data such that they could verify the analysis published in his 1998 paper. Why was this so? Reproducibility is a major pillar of the scientific process, yet this data was only dragged out of Dr. Mann by an act of the U.S. Congress. Any objective person should find that disturbing, given that the IPCC's reports are all primarily based on Dr. Mann's conclusions (reports whose aim is to impose significant costs on the U.S. economy in the name of preventing a problem that may or may not exist).

As I understand it Mann's findings have been repeatedly verified by credible scientists; a fact that you conveniently leave out. Mann's unwillingness to turn over data was in request to M&M's request. You seem like a learned man, and must realize that McIntyre and McKitrick are not taken seriously in the scientific community.

It would be like turning over evolution data to Jerry Falwell; to give Falwell the chance to say that he couldn't reproduce the results.

 

[ALiberalModerate]

Two Canadian experts, Stephen McIntyre and Ross McKitrick (known as "M&M" in discussions of the climate debate), found enormous flaws in the hockey stick figures being trotted out by the Left to scare people into unreasonable anti-corporate regulations.

http://www.nationalreview.com/comment/murray200311030813.asp
http://www.climateaudit.org/
http://www.uoguelph.ca/~rmckitri/research/trc.html


Before you go confirming my observation that when the Left is confronted by science that doesn't conform to what they want to be true, they dissmiss or undermine it without actually intellectually confronting the assertions its based on (and this tendency does NOT stop with science), you might want to at least try to form some kind of intelligible refutation.

In short, no one is interested in your usual defensive smear tactics.

This critique of Mann’s “Hockey Stick” is rather outdated. Stephen McIntyre and Ross McKitrick, critiqued the proxy data that Mann’s research team used to reconstruct Global Climate temperatures over the last millennia. The problem with your argument at this point is that their critique is from 5 years ago, and since then no less than 6 peer reviewed studies confirmed Mann’s conclusion. More importantly though, as numerous media outlets reported last week, The National Academy of Sciences has confirmed Mann’s “Hockey Stick” after a broad review of scientific work requested by congress. You can read more here: http://www.forbes.com/home/feeds/ap/2006/06/22/ap2834213.html

So, at this point, Stephen McIntyre and Ross McKitrick’s claims have been thoroughly debunked. It is also worth pointing out that you referred to them as experts. However, neither of them are climatologists. Instead, Stephen McIntyre is a retired from the mining industry and simply holds a 4 year degree in mathematics. Ross McKitrick is a conservative economist.

So it would seem that you are claiming that the opinions of a retired miner, and an economist, should take precedence over the findings of the National Academy of Sciences?

As far as confronting their actual allegations, I do not see the point in that as the National Academy of Sciences has already refuted them. Just the same, if you would actually like to debate the science behind Global Warming, I will certainly debate it with you.

 

[ALiberalModerate]

That said, I will use this opportunity to point out that the National Academies of Sciences' Board on Atmospheric Sciences and Climate just released their much-anticipated report [Surface Temperature Reconstructions for the Last 2,000 Years (2006)] aimed at analyzing the available evidence for the types of claims made in MAN98 and subsequent papers based on MAN98. The full report can be found here and if you're interested in my post you should at least read the 4-page summary.
.....

You seem to be implying that:

1. The medieval warm period was warmer than it is today.

2. You are hyping the doubt in the NAS findings.

The following is the actual NAS findings news release:

FOR IMMEDIATE RELEASE
'High Confidence' That Planet Is Warmest in 400 Years;
Less Confidence in Temperature Reconstructions Prior to 1600

WASHINGTON -- There is sufficient evidence from tree rings, boreholes, retreating glaciers, and other "proxies" of past surface temperatures to say with a high level of confidence that the last few decades of the 20th century were warmer than any comparable period in the last 400 years, according to a new report from the National Research Council. Less confidence can be placed in proxy-based reconstructions of surface temperatures for A.D. 900 to 1600, said the committee that wrote the report, although the available proxy evidence does indicate that many locations were warmer during the past 25 years than during any other 25-year period since 900. Very little confidence can be placed in statements about average global surface temperatures prior to A.D. 900 because the proxy data for that time frame are sparse, the committee added.

Scientists rely on proxies to reconstruct paleoclimatic surface temperatures because geographically widespread records of temperatures measured with instruments date back only about 150 years. Other proxies include corals, ocean and lake sediments, ice cores, cave deposits, and documentary sources, such as historic drawings of glaciers. The globally averaged warming of about 1 degree Fahrenheit (0.6 degrees Celsius) that instruments have recorded during the last century is also reflected in proxy data for that time period, the committee noted.

The report was requested by Congress after a controversy arose last year over surface temperature reconstructions published by climatologist Michael Mann and his colleagues in the late 1990s. The researchers concluded that the warming of the Northern Hemisphere in the last decades of the 20th century was unprecedented in the past thousand years. In particular, they concluded that the 1990s were the warmest decade, and 1998 the warmest year. Their graph depicting a rise in temperatures at the end of a long era became known as the "hockey stick."

The Research Council committee found the Mann team's conclusion that warming in the last few decades of the 20th century was unprecedented over the last thousand years to be plausible, but it had less confidence that the warming was unprecedented prior to 1600; fewer proxies -- in fewer locations -- provide temperatures for periods before then. Because of larger uncertainties in temperature reconstructions for decades and individual years, and because not all proxies record temperatures for such short timescales, even less confidence can be placed in the Mann team's conclusions about the 1990s, and 1998 in particular.

The committee noted that scientists' reconstructions of Northern Hemisphere surface temperatures for the past thousand years are generally consistent. The reconstructions show relatively warm conditions centered around the year 1000, and a relatively cold period, or "Little Ice Age," from roughly 1500 to 1850. The exact timing of warm episodes in the medieval period may have varied by region, and the magnitude and geographical extent of the warmth is uncertain, the committee said. None of the reconstructions indicates that temperatures were warmer during medieval times than during the past few decades, the committee added.

The news release goes on to say:

The scarcity of precisely dated proxy evidence for temperatures before 1600, especially in the Southern Hemisphere, is the main reason there is less confidence in global reconstructions dating back further than that. Other factors that limit confidence include the short length of the instrumental record, which is used to calibrate and validate reconstructions, and the possibility that the relationship between proxy data and local surface temperatures may have varied over time. It also is difficult to estimate a mean global temperature using data from a limited number of sites. On the other hand, confidence in large-scale reconstructions is boosted by the fact that the proxies on which they are based generally exhibit strong correlations with local environmental conditions. Confidence increases further when multiple independent lines of evidence point to the same general phenomenon, such as the Little Ice Age.
Collecting additional proxy data, especially for years before 1600 and for areas where the current data are relatively sparse, would increase our understanding of temperature variations over the last 2,000 years, the report says. In addition, improving access to data on which published temperature reconstructions are based would boost confidence in the results. The report also notes that new analytical methods, or more careful use of existing methods, might help circumvent some of the current limitations associated with large-scale reconstructions.

The committee pointed out that surface temperature reconstructions for periods before the Industrial Revolution -- when levels of atmospheric greenhouse gases were much lower -- are only one of multiple lines of evidence supporting the conclusion that current warming is occurring in response to human activities, and they are not the primary evidence.

The National Research Council is the principal operating arm of the National Academy of Sciences and the National Academy of Engineering. It is a private, nonprofit institution that provides science and technology advice under a congressional charter. A committee roster follows.

Copies of Surface Temperature Reconstructions for the Last 2,000 Years will be available from the National Academies Press; tel. 202-334-3313 or 1-800-624-6242 or on the Internet at http://www.nap.edu. Reporters may obtain a pre-publication copy from the Office of News and Public Information (contacts listed above).

http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=11676

The following paragraph:

The committee pointed out that surface temperature reconstructions for periods before the Industrial Revolution -- when levels of atmospheric greenhouse gases were much lower -- are only one of multiple lines of evidence supporting the conclusion that current warming is occurring in response to human activities, and they are not the primary evidence.

As you can see, their findings in no way should be hyped to indicate that they question Global Warming. The point out that there are multiple lines of evidence supporting the conclusion that current warming is occuring in response to human activities, and Mann's Hockey Stick is not even the primary evidence for this conclusion. They mearly point out that the proxy data does not lend itself to the level of confidence that Mann conclusion implies.

I might also point out that the official position of them National Academy of Sciences is that Global Warming is real, and human activity is the primary factor in that warming.

Source: http://www4.nationalacademies.org/onpi/webextra.nsf/web/climate?OpenDocument

The problem with Global Warming deniers, is that they pick and choose the evidence they want to critque, then they imply that the entire Global Warming Theory hinges on that evidence. The problem for them is that there are muliple lines of evidence supporting the notion that the world is indeed warming, and that human activity is the primary cause of that warming.

 

[pendulum_jaw]

As I understand it Mann's findings have been repeatedly verified by credible scientists; a fact that you conveniently leave out. Mann's unwillingness to turn over data was in request to M&M's request. You seem like a learned man, and must realize that McIntyre and McKitrick are not taken seriously in the scientific community.

It would be like turning over evolution data to Jerry Falwell; to give Falwell the chance to say that he couldn't reproduce the results.

Whether or not Mann's findings have been verified by those whom you believe are 'credible scientists' or not is irrelevant. As a scientist, I would personally be suspect of any publicly-funded research team that refused to publicize datasets or materials and methods used in the study. I would wager that most of the scientific community, American taxpayers, and politicians would agree with me on this point. In fact, full disclosure of all these things is generally required for publication. The basic idea is easy to understand: science must be reproducible and transparent. Steps taken in an analysis must be clear and easy to follow. Your assertion that he only refused to disclose the data because of two specific researchers is may or may not be true, but the fact that he refused disclosure is unacceptable. If scientific results are valid, they will withstand peer scrunity and emerge stronger because of it. Only weak results need to fear peer scrutiny. Mann's actions were highly irregular and I believe suspicious. Couple this to the fact that this is a highly-charged political issue with alot of money, power, and careers at stake and one has to conclude that Mann's behavior is not the kind of behavior we want to encourage within the scientific community.

Back to your assertion that Mann's results have been verified by independent scientists. You really need to provide a source for this because all papers that I've seen (and I will admit I haven't been completely thorough in researching this) are actually papers by scientists who have collaborated with Mann on earlier projects, and those papers use the same criticized data and methodology that Mann's 1998 paper used. I personally wouldn't consider such work independent validation of Mann's conclusions. Plus, the point of M&M's criticism in part (I haven't read it all) is that the data and statistical methodologies used were flawed. The fact that Nature (the journal who published the 1998 paper) required Mann issue a corrigendum (a correction of errors associated with his earlier paper) based on the M&M criticism lends at least some credibility to their claims. Similarly, Mann was also required by Nature to submit another supplementary data section to help clarify his analysis to the scientific community.

Finally, my post above details the NAS report just released this month, which definitely does not endorse Mann's conclusions. In fact, it calls the validity of Mann's conclusions into serious question. This is at odds with your implication that Mann's work have been sufficiently validated by other scientists. I encourage you to read the report for yourself.

 

[pendulum_jaw]

You seem to be implying that:

1. The medieval warm period was warmer than it is today.

2. You are hyping the doubt in the NAS findings.

This is a reactionary post which illegitimately accuses me of 'implying the medieval war period was warmer than it is today' and of 'hyping the doubt in the NAS findings'. I am guilty of neither accusation because the point of my post was not to assess the content of the NAS report, but to use that content to demonstrate how the media misinterprets and/or exaggerates scientific reports. The other claim I made was that certain conclusions made by the report's authors clearly indicate that Mann's temperature record is indeed a contentious issue, a fact that many posters in this forum have rejected. I never 'implied' or 'hyped' anything and it's not very sporting of you to accuse me of doing so. Build straw man; knock down straw man, eh?

You then go on to post exerpts from the very report that I referenced and finally make the accusation:

The problem with Global Warming deniers, is that they pick and choose the evidence they want to critque, then they imply that the entire Global Warming Theory hinges on that evidence. The problem for them is that there are muliple lines of evidence supporting the notion that the world is indeed warming, and that human activity is the primary cause of that warming.

So you're implying that I've 'critiqued' some kind of 'evidence of Global Warming' here, which I most certainly did not. The report is about the controversy in historical temperature reconstructions, not 'Global Warming' (hence, the title "Surface Temperature Reconstructions for the Last 2,000 Years"). At least try to stay within the scope of the discussion, or if you wish to widen the scope declare your intentions to do so.

I take offense to being lumped in with 'Global Warming deniers', whoever they may be and whatever they may believe. 'Global Warming' is a highly ambiguous term which means different things to different people. If you wish to accuse me of something, be specific and back up your accusation. Regarding your accusation, it's interesting how you conclude that the problem for [people that you disagree with] is that there are multiple lines of evidence [that they are wrong]. Not a very powerful way to argue, in essence claiming that they're wrong because 'you say so'. It does however seem to be typical of many on this forum.

The NAS report is a political one written by a team of scientists, probably not all of whom agree with one another on the issue. If you've read the report you know that it is internally inconsistent--that is it says one thing about a subject and one place, and says almost the complete opposite about it in another. I suspect the authors have tried to appease both sides of the issue, and indeed, it seems that both sides are claiming a victory with its conclusions. You seem more guilty of your own accusation--of 'picking and choosing evidence to use'--than I. The dual nature of the report is such that one could do this (choose supporting quotes) no matter which side of the issue one was on. It is a fact that you chose to quote a part of the 'press release' that cast doubt on the Medival Warming Theory; but you're not fooling anyone because there are parts in the actual report itself that lend credence to the Theory. You nitpicked the news release, not I. Contary to your accusations, I personally do not care whether the Medival Warming Theory is truth or farce--but I don't appreciate people trying to ram their own misunderstandings of science down the public's throat. And that was precisely the phenomenon I was addressing in my post.

The report is clear on the point that I referenced: that it does not put much confidence in the conclusions published in Dr. Mann's 1998 Nature paper. I was and still are correct to point out that this undermines the notions that Mann's only critics are two crazy Canadian researchers (M&M) out on a personal vendetta or that there is widespread consensus that his temperature reconstruction is accurate. Both notions are pure bilge. It is significant that the NAS failed to endorse Mann's conclusions, given their political position. Faulty science will eventually come crumbling down; it's only a matter of time.

 

[ALiberalModerate]

The report is clear on the point that I referenced: that it does not put much confidence in the conclusions published in Dr. Mann's 1998 Nature paper. I was and still are correct to point out that this undermines the notions that Mann's only critics are two crazy Canadian researchers (M&M) out on a personal vendetta or that there is widespread consensus that his temperature reconstruction is accurate. Both notions are pure bilge. It is significant that the NAS failed to endorse Mann's conclusions, given their political position. Faulty science will eventually come crumbling down; it's only a matter of time.

I may well have been over zealous in widening the argument. However, the implication from the original author of this thread is that just because some have questioned Mann's 8 year old report on temperature trends, that this somehow invalidates Anthropogenic Global Warming theory. That is total crap. As I stated, there are multiple lines of evidence for Anthropogenic Global Warming theory. In your thread that you started, I elaborated on some of them.

 

[pendulum_jaw]

This critique of Mann’s “Hockey Stick” is rather outdated. Stephen McIntyre and Ross McKitrick, critiqued the proxy data that Mann’s research team used to reconstruct Global Climate temperatures over the last millennia. The problem with your argument at this point is that their critique is from 5 years ago, and since then no less than 6 peer reviewed studies confirmed Mann’s conclusion. More importantly though, as numerous media outlets reported last week, The National Academy of Sciences has confirmed Mann’s “Hockey Stick” after a broad review of scientific work requested by congress. You can read more here: http://www.forbes.com/home/feeds/ap/2006/06/22/ap2834213.html[/SIZE][/FONT]

(highlighting mine)

This is pure drivel. Your claim that the NAS report confirmed the hockey-stick graph is false. You either don't understand the report or do understand the report and are lying. I'd guess the former, and given that you cited the Forbes article which misrepresents the report's findings (by the way thanks for adding another example of media incompetence to my above list), I'd say that's where you got this idea.

It's instructive to look at the relevant portion of Forbes' article:

"The National Academy scientists concluded that the Mann-Bradley-Hughes research from the late 1990s was "likely" to be true, said John "Mike" Wallace, an atmospheric sciences professor at the University of Washington and a panel member. The conclusions from the '90s research "are very close to being right" and are supported by even more recent data, Wallace said."

Firstly, it is not, as you stated, the authors of the report who made this absurd claim, but "John Wallace". That you mistook a single professor's opinion of the report for the actual conclusion of the report is your failing. Secondly he stated that it was "likely" to be true and that the conclusions are "very close to being right". You went a step further and said the report "confirms" the hockey-stick graph. In reality, neither of you are close to what the report really stated. Here it is:

"Based on the analyses presented in the original papers by Mann et al. and this newer supporting evidence, 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. 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. 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."

So while the committee states that it finds the MAN98 paper's conclusions 'plausible' (which carries zero weight, since almost anything can be considered plausible), it then states that 1) it has a 'high level of confidence' in the existence of the "Little Ice Age", which Mann's reconstruction got wrong; and 2) that it has "[e]ven less confidence...in the original conclusions by Mann...that 'the 1990s are likely the warmest decade, and 1998 the warmenst year, in the last millennium." So the authors state that they have little confidence in Mann's conclusions and that they have a high level of confidence in an ice age period that undermines the credibility of Mann's temperature data. Hardly a confirmation of Mann's temperature reconstruction.

So here we have a real world example of precisely what I have been arguing in this post: a person (SouthernDemocrat) being influenced by a media source's (Forbes) blatant misunderstanding and reporting of the results of a scientific analysis (the NAS report). And now SouthernDemocrat is perpetuating Forbes' misinformation. This is how it works, folks.

 

[cascadian]

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."

I'd be interested in seeing you relate this criticism to MM's. As they seem somewhat different from this reading.

So while the committee states that it finds the MAN98 paper's conclusions 'plausible' (which carries zero weight, since almost anything can be considered plausible), it then states that 1) it has a 'high level of confidence' in the existence of the "Little Ice Age", which Mann's reconstruction got wrong; and 2) that it has "[e]ven less confidence...in the original conclusions by Mann...that 'the 1990s are likely the warmest decade, and 1998 the warmenst year, in the last millennium." So the authors state that they have little confidence in Mann's conclusions and that they have a high level of confidence in an ice age period that undermines the credibility of Mann's temperature data. Hardly a confirmation of Mann's temperature reconstruction.

So when they say "plausible" it carries no weight but when they say "less confidence" it suddenly means something? Both statments seem equally open ended to me.

So here we have a real world example of precisely what I have been arguing in this post: a person (SouthernDemocrat) being influenced by a media source's (Forbes) blatant misunderstanding and reporting of the results of a scientific analysis (the NAS report). And now SouthernDemocrat is perpetuating Forbes' misinformation. This is how it works, folks.

Even we granted that, are you saying that Forbes is some kind of mouthpiece for the Left?! If anything, this demonstrates that HCGW is mainstream.

 

[StrawHat]

Be it real or not, it only makes sense to treat global warming as a very real problem. I'm sure it would foster new industry as well, so I don't see what anyone's problem with it is.

 

[Gill]

I'd be interested in seeing you relate this criticism to MM's. As they seem somewhat different from this reading.

If you had read any of M&M's criticism of Mann's work, you would know that they have no opinion regarding global warming. Their criticism of Mann is that he uses poor statistical methods to reach his conclusions.

I would also like to reiterate a comment made by pendulum_jaw. If you researched the papers that "confirm" Mann's work, you will find that they are authored by scientists that have worked with him on this and other issues.

 

[ALiberalModerate]

If you had read any of M&M's criticism of Mann's work, you would know that they have no opinion regarding global warming. Their criticism of Mann is that he uses poor statistical methods to reach his conclusions.

I would also like to reiterate a comment made by pendulum_jaw. If you researched the papers that "confirm" Mann's work, you will find that they are authored by scientists that have worked with him on this and other issues.

Anthropogenic Global Warming is a theory backed by multiple lines of evidence. In fact, Mann's "Hockey Stick" is not even the strongest line of evidence.

For example, a study just concluded that glaciers worldwide are retreating at a faster rate than in at least 5,200 years.

Professor Thompson said the research was based on nearly 50 scientific expeditions to seven mountain glaciers over the past three decades, including the Huascaran and Quelccaya ice caps in Peru, the Sajama ice cap in Bolivia and the Dunde and Puruogangri ice caps in China. He said: "We have a record going back 2,000 years and when you plot it out, you can see the medieval warm period [from 1000 to 1300] and the little ice age [from 1600 to 1850]. And in that same record, you can clearly see the 20th century and the thing that stands out is how unusually warm the last 50 years have been. There hasn't been anything like it, not even in the medieval warm period.

"The fact that the isotope values in the last 50 years have been so unusual means that things are dramatically changing."

The most dramatic evidence comes from 28 sites where the retreating ice has exposed plants that have been frozen and preserved for between 5,000 and 6,000 years by the glacier's base.

This was widely reported about a month back. A quick Google Search found this article on the study that was reported in the Independent. Common Dreams evidently archived the article, you can read more here: http://www.commondreams.org/headlines06/0627-01.htm

Moreover, the central critique Global Warming deniers used in the past was that we had no way of knowing that the troposphere was warming. However, a recent NASA study found that the troposphere is indeed warming, the surface is warming, and the stratosphere is cooling. That is completely consistent with Greenhouse Global Warming, and a cooling stratosphere rules at warming due to increased solar activity.

 

[Gill]

Anthropogenic Global Warming is a theory backed by multiple lines of evidence. In fact, Mann's "Hockey Stick" is not even the strongest line of evidence.

For example, a study just concluded that glaciers worldwide are retreating at a faster rate than in at least 5,200 years.



This was widely reported about a month back. A quick Google Search found this article on the study that was reported in the Independent. Common Dreams evidently archived the article, you can read more here: http://www.commondreams.org/headlines06/0627-01.htm

Moreover, the central critique Global Warming deniers used in the past was that we had no way of knowing that the troposphere was warming. However, a recent NASA study found that the troposphere is indeed warming, the surface is warming, and the stratosphere is cooling. That is completely consistent with Greenhouse Global Warming, and a cooling stratosphere rules at warming due to increased solar activity.

That's a very nice post. Unfortunately, it has zero relevance with my reply that you quoted.

 

[ALiberalModerate]

That's a very nice post. Unfortunately, it has zero relevance with my reply that you quoted.

I would argue that simply criticizing Mann's work and somehow implying that criticism calls into question Anthropogenic Global Warming is an intellectually dishonest and or missinformed criticism. As I pointed out, Anthropogenic Global Warming is backed by multiple lines of evidence. There are multiple lines of evidence to support the notion that the earth's climate is warmer today than it has been in at least 2000 to 5000 years, and Mann's Hockey Stick is not even the strongest evidence in support of that notion. Even if Mann's study was incredibly flawed, you still would have a mountain of evidence to overcome before you could even begin to question the bulk of the science behind Anthropogenic Global Warming.

 

[Gill]

This critique of Mann’s “Hockey Stick” is rather outdated. Stephen McIntyre and Ross McKitrick, critiqued the proxy data that Mann’s research team used to reconstruct Global Climate temperatures over the last millennia. The problem with your argument at this point is that their critique is from 5 years ago,

Not true... M&M's paper was published in 2005 in the Geophysical Research Letters.

Following are some interesting comments by one or the reviewers:

S. McIntyre and R. McKitrick have written a remarkable paper on a subject of great importance. What makes the paper significant is that they show that one of the most important and widely known results of climate analysis, the 'hockey stick' diagram of Mann et al.,was based on a mistake in the application of a mathematical technique known as principal component analysis (PCA)."

"McIntyre and McKitrick found a non-standard normalization procedure in the Mann et al. analysis. Their paper describes this procedure; it was an apparently innocent one of normalization, but it had a major effect on their results. The Mann et al. normalization tends to significantly increase the variance of data sets that have the hockey-stick shape. In the Mann et al. data set, this turned out to be bristlecone pines in the western United States. Thus the hockey stick plot, rather than representing a true global average of climate for the past thousand years, at best represented the behavior of climate in the western U.S. during that period.This is an astonishing result. I have looked carefully at the McIntyre and McKitrick analysis, and I am convinced that their work is correct."

"I urge you not to shy away from this paper because of its potential controversy. The whole field of global warming is currently suffering from the fact that it has become politicized. Science really depends for its success on an open dialogue, with critics on both sides being heard. McIntyre and McKitrick present a cogent analysis of the global warming data. They do not conclude that global warming is not a problem; they don't even conclude that the medieval warm period really was there. All they do is correct the analysis of prior workers, in a way that must ultimately help us in our understanding of past climate, and predictions of future climate. That makes this a very important paper. I strongly urge you to publish it."

There are so many abnormalities in the Mann et al paper as well as the followup papers supporting the Mann hockey stick that a very putrid smell is cast over the whole GW debate. What is really sad is that the IPCC published the results of the Mann et al paper without verifying the data presented. This fact alone casts doubt on the IPCC as well as Nature's review process who subsequently published it.

 

[ALiberalModerate]

Not true... M&M's paper was published in 2005 in the Geophysical Research Letters.

Following are some interesting comments by one or the reviewers:



There are so many abnormalities in the Mann et al paper as well as the followup papers supporting the Mann hockey stick that a very putrid smell is cast over the whole GW debate. What is really sad is that the IPCC published the results of the Mann et al paper without verifying the data presented. This fact alone casts doubt on the IPCC as well as Nature's review process who subsequently published it.

Once again, you are missing the point. An economist, and a laymen have questioned Mann’s research methods behind the Hockey Stick. So, lets just take your contention and say that there are enough flaws in Mann’s methods as to render his research inconclusive.

Your problem is that once again, as I have pointed out again and again, Anthropogenic Global Warming is backed my multiple lines of evidence. The notion that the earth is warmer today than in at least 2000 years, and as newer evidence is showing, probably 5000 years, is backed by multiple lines of evidence. Mann’s Hockey Stick is simply one of those lines, and is not even the strongest line of evidence anymore. Mann’s findings were published some 8 years ago. Scores of studies have been conducted since then, the latest of which was one by The National Academy of Sciences, and the one I published above that irrefutably shows that we are seeing markedly stronger warming today than in at least 5,200 years.

You cant just pick and choose which lines of evidence you want to attack in a theory that is supported by multiple lines. Even if you throw out Mann’s findings altogether, there is still mountains of evidence that you would have to overcome before throwing Anthropogenic Global out of the realm of Scientific Consensus and back into question.

Let me go ahead and also point out that your quote you provided in bold is from Junk Science, a site ran by a paid advocate, a paid advocate for the fossil fuels and chemical industries. I mean this is your source that you are pitting against all of mainstream science.

Honestly, what is the source of your bias against mainstream science here? Why would you lend so much credibility to paid advocates of the fossil fuels industry, and zero credibility to mainstream science? Do you work for the oil industry?

 

[Gill]

Once again, you are missing the point. An economist, and a laymen have questioned Mann’s research methods behind the Hockey Stick. So, lets just take your contention and say that there are enough flaws in Mann’s methods as to render his research inconclusive.

Your problem is that once again, as I have pointed out again and again, Anthropogenic Global Warming is backed my multiple lines of evidence. The notion that the earth is warmer today than in at least 2000 years, and as newer evidence is showing, probably 5000 years, is backed by multiple lines of evidence. Mann’s Hockey Stick is simply one of those lines, and is not even the strongest line of evidence anymore. Mann’s findings were published some 8 years ago. Scores of studies have been conducted since then, the latest of which was one by The National Academy of Sciences, and the one I published above that irrefutably shows that we are seeing markedly stronger warming today than in at least 5,200 years.

You cant just pick and choose which lines of evidence you want to attack in a theory that is supported by multiple lines. Even if you throw out Mann’s findings altogether, there is still mountains of evidence that you would have to overcome before throwing Anthropogenic Global out of the realm of Scientific Consensus and back into question.

t
And once again, you are missing the point. The title of this thread is Debunking the Left's War on Science and the OP is about the paper published by M&M. The thread is not about all these other lines of evidence you claim, it is about Mann's hockey stick.

Stay on topic.

 

[ALiberalModerate]

t
And once again, you are missing the point. The title of this thread is Debunking the Left's War on Science and the OP is about the paper published by M&M. The thread is not about all these other lines of evidence you claim, it is about Mann's hockey stick.

Stay on topic.

The topic is warming. Aquapub makes the absurd insinuation that just because the Hockey Stick was called into question in a single peer reviewed work, that this someone invalidates the theory. I am merely pointing out that the National Academy of Sciences would disagree, and even if the Hockey Stick was purely bunk, there are still far stronger lines of evidence supporting the same conclusion anyway.

 

[Gill]

The topic is warming. Aquapub makes the absurd insinuation that just because the Hockey Stick was called into question in a single peer reviewed work, that this someone invalidates the theory. I am merely pointing out that the National Academy of Sciences would disagree, and even if the Hockey Stick was purely bunk, there are still far stronger lines of evidence supporting the same conclusion anyway.

It's actually been debunked in at least three peer reviewed science publications. There may be more by now.

 

[ALiberalModerate]

It's actually been debunked in at least three peer reviewed science publications. There may be more by now.

It has not been debunked, but rather, some of his proxy data has been questioned. It is called the peer review process. Moreover, as I have already pointed out, even if Mann's proxy data and methods were flawed, and thus his conclusions were deemed inconclusive, then, you would still have to someone challenge the scores of other lines of evidence that point to much of the same conclusions.

 

[Gill]

It has not been debunked, but rather, some of his proxy data has been questioned. It is called the peer review process. Moreover, as I have already pointed out, even if Mann's proxy data and methods were flawed, and thus his conclusions were deemed inconclusive, then, you would still have to someone challenge the scores of other lines of evidence that point to much of the same conclusions.

It has been proven that when correct data and statistical methods are used, the hockey stick goes away and the 20th century is no longer the hottest in the last 1,000 years.

Since this was the main point of the paper, I would call it debunked.

 

[ALiberalModerate]

It has been proven that when correct data and statistical methods are used, the hockey stick goes away and the 20th century is no longer the hottest in the last 1,000 years.

Since this was the main point of the paper, I would call it debunked.

So your contention is that since Mann’s proxy data and methods have been questioned, that one most automatically conclude that the 20th century is no longer abnormal in terms of warmth.

If you are correct, then how do you explain the findings of this study:

Their conclusions mark a massive climate shift to a cooler regime that occurred just over 5,000 years ago, and a more recent reversal to a much warmer world within the last 50 years.

The evidence also suggests that most of the high-altitude glaciers in the planet’s tropical regions will disappear in the near future. The paper was included in the current issue of the journal Proceedings of the National Academy of Science.

Lastly, the research shows that in most of the world, glaciers and ice caps are rapidly retreating, even in areas where precipitation increases are documented. This implicates increasing temperatures and not decreasing precipitation as the most likely culprit. ……..

For the last three decades, Thompson has led nearly 50 expeditions to remote ice caps and glaciers to drill cores through them and retrieve climate records. This study includes cores taken from the Huascaran and Quelccaya ice caps in Peru; the Sajama ice cap in Bolivia; the Dunde, Guliya, Puruogangri and Dasuopu ice caps in China.

For each of these cores, the team -- including research partner Ellen Mosley-Thompson, professor of geography at Ohio State – extracted chronological measurements of the ratio of two oxygen isotopes -- O18 and O16 -- whose ratio serves as an indicator of air temperature at the time the ice was formed. All seven cores provided clear annual records of the isotope ratios for the last 400 years and decadally averaged records dating back 2000 years.

“We have a record going back 2,000 years and when you plot it out, you can see the Medieval Warm Period (MWP) and the Little Ice Age (LIA),” Thompson said. During the MWP, 70O to 1000 years ago, the climate warmed in some parts of the world. The MWP was followed by the LIA, a sudden onset of colder temperatures marked by advancing glaciers in Europe and North America.

“And in that same record, you can clearly see the 20th Century and the thing that stands out – whether you look at individual cores or the composite of all seven – is how unusually warm the last 50 years have been.

“There hasn’t been anything in the record like it – not even the MWP,” Thompson said.

“The fact that the isotope values in the last 50 years have been so unusual means that things are dramatically changing. That’s the real story here.”

While the isotope evidence is clear throughout all of the cores, Thompson says that the more dramatic evidence is the emergence of unfossilized wetland plants around the margin of the Quelccaya ice cap, uncovered as the ice retreated in recent years.

First discovered in 2002, the researchers have since identified 28 separate sites near the margin of the ice cap where these ancient plants have been exposed. Carbon-dating revealed that the plants range in age from 5,000 to 6,500 years old.

“This means that the climate at the ice cap hasn’t been warmer than it is today in the last 5,000 years or more,” Thompson said. “If it had been, then the plants would have decayed.”

Read more here: http://space.physorg.com/news70621539.html


So what we have, is an 8 year old study conducted by Mann’s team that concluded that the twentieth century was the warmest in 1000 years and probably 2000 years. Some of the methods and proxy data behind that study was questioned. However, even strong evidence has since been found that shows that the earth’s climate is in fact warmer than it has been in at least 2000 years and probably 5000 years. Do you understand the implication here? We now have an exhaustive study just released that through multiple lines of evidence has a clear record of climate for the past 2000 years can clearly show the degree of warmth during the Medieval Warm Period, can clearly show the degree of cooling during the Little Ice Age, and then can clearly show the level of unprecedented warmth during the last 50 years. That is as clear and as solid as it gets. Moreover, because of this unprecedented warmth during the last 50 years, glaciers are uncovering plants that had been frozen for 5,200 years.

So, how do you reconcile those lines of supportive evidence to you contention that the climate is not unusually warm today?