TCS Daily

Hockey Stick Shortened?

By Duane D. Freese - June 27, 2006 12:00 AM

"We have 25 or so years invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it?"
-- Phil Jones in a reply to climate skeptic Warwick Hughes in February 2005 as confirmed and reported by climatologist Hans Vans Storch at a National Academy of Sciences hearing March 2 on "Scientific Efforts to reconstruct surface temperature records over the last 1,000 to 2,000 years."

"Getting caught is the mother of invention."
-- Robert Byrne

"People say that in politics, it's not the crime, it's the cover-up. What that saying ignores is that most of the time, the cover-up works just fine."
-- George Carlin

The most gratifying thing about the National Academy of Science panel report last week into the science behind Michael Mann's past temperature reconstructions - the iconic "hockey stick" isn't what the mainstream media have been reporting -- the panel's declaration that the last 25 years of the 20th Century were the warmest in 400 years. After all, 400 years ago was 1600, and as the panel noted that was in the midst of a 350 year period from 1500 to 1850 where "a wide variety of evidence" supports the finding of a "Little Ice Age." So wouldn't you expect some period coming out of an ice to be warmer than any period during the Ice Age?

The important thing the panel did was to take a much-needed slap at the attitude expressed by Jones quoted above, which had become dangerously prevalent in some of the climate science community.

The panel told scientists that they should strive to provide data and "that a clear explanation of analytical methods is mandatory" and that "paleoclimate research would benefit if individual researchers, professional societies, journal editors, and funding agencies continued to improve their efforts to ensure that ... existing open access practices are followed."

Karl Popper described the scientific method as "proposing bold hypotheses, and exposing them to the severest criticism, in order to detect where we have erred." A recent problem with some areas of climate science has been that much of the data and methodology for arriving at conclusions have been hidden, making that "severest criticism" difficult. That was clearly the case with Michael Mann's past temperature reconstructions.

Mann's published reconstruction in Nature in 1998 went back 600 years; in 1999 he extended the reconstruction back 1,000 years. The studies dismissed the Medieval Warm Period and Little Ice Age as regional phenomena, and became regarded by some as the "smoking gun" proving that human influence was responsible for the bulk of the warming in the 20th Century.

In 2001, the graphical representation of Mann's work became a key feature in the Intergovernmental Panel on Climate Change's (IPCC) Third Assessment. The IPCC report asserted that "the 1990s has been the warmest decade and 1998 the warmest year in the millennium."

While Mann is doing much now saying that his caveats about temperature were ignored by the media and the IPCC -- an excuse the NAS panel accepted -- he and his crew certainly did much to discredit those who raised questions about his work.

In 2003, Steven McIntyre, a former mining executive in Toronto, decided to test Mann's claim, made to a Senate committee, that the IPCC's assessment deserved respect because "[t]he IPCC carries out a process for developing its summarization of the understanding of science that leads to one of the most rigorously peer reviewed scientific documents in existence."

McIntyre contacted Mann to get the data for his graph, thinking that they would be appropriately archived and readily available for replication and review. It quickly became more complicated than that, and he ended up having to enlist the University of Guelph economics professor Ross McKitrick in a three-year quest to get basic information. As McKitrick summarized their findings:

"Nature never verified that data were correctly listed: as it happens they weren't. Nature never verified that data archiving rules were followed: they weren't. Nature never verified that methods were accurately stated: they weren't. Nature never verified that stated methods yield the stated results: they don't. Nature undertook only minimal corrections to its publication record after notification of these things, and even allowed authors to falsely claim that their omissions on these things didn't affect their published results. The IPCC's use of the hockey stick was not incidental: it is prominent throughout the 2001 report. Yet they did not subject it to any independent checking. ... They allowed chapter authors to heavily promote their own work with little or no oversight. They published false claims about the hockey stick's statistical robustness and have never made any effort to retract them."

What McIntyre and McKitrick got for bringing this to light, as well as exposing numerous statistical and methodological flaws in the studies including that the studies, was mostly brickbats and scorn by the paleoclimatology community. This until Hans Van Storch, director of the Institute of Coastal Research at GKSS Research Center in Germany, wrote in a letter to Science and Anders Moberg of Stockholm University in Sweden in a letter to Nature, announced they had found more natural variation than Mann over the last 1,000 years, raising again questions about the level of human contribution to 20th Century warmth.

After an article appeared in the Wall Street Journal about their problems, McIntyre and McKitrick gained an ally in a powerful House Energy and Commerce Committee Chairman Joe Barton, R-Texas. Barton last summer issued letters to Michael Mann and his co-authors Malcolm Hughes and Raymond Bradley, regarding their studies, along with IPCC chairman Rajendra Pachauri and National Science Foundation's Arden Bement. In the letters, Barton noted that "sharing data and research results is a basic tenet of open scientific inquiry" and asked whether federal access guidelines for information from taxpayer-funded research were being followed.

That woke up the scientific community and mainstream media. But it wasn't to praise Barton, but to pummel him. How dare he ask for taxpayer funded information from a scientist. Seeking such amounted to a witch hunt and an attempt to intimidate honest scientists, his critics argued. Let the scientific process work. The IPCC will again review the science in 2007, etc.

In the heat of the exchange, a ray of light did shine. NAS chairman Ralph Cicerone wrote Barton that "the House Commerce Committee is probably not the best way to resolve a scientific issue, and a focus on individual scientists can be intimidating." He offered that if the committee wanted additional information regarding the state of the scientific knowledge" in Mann's area that the NAS "would be willing to create an expert panel."

That was arranged through the House Science Committee. The panel concluded we know a lot about the last 400 years, but have far less confidence in the period 900 to 1600, and not much confidence at all about prior to 900. The panel indicated it is "plausible" that the last 25 years of the 20th Century were warmer than any period in the last 1,000. But Mann's and the IPCC's claims about the last 1990s "likely" being the warmest decade and 1998 the warmest year had no plausibility. And Mann's attacks on McIntyre and McKitrick for pointing out flaws in his statistical techniques received a comeuppance by the panel on page 107 of the report, when the panel diplomatically stated:

"Some of these criticisms (by McIntyre and McKitrick) are more relevant than others, but taken together, they are an important aspect of a more general finding of this committee, which is that uncertainties of the published reconstructions have been underestimated."

The hockey stick, in short, is 600 years shorter than it was before and the uncertainties for previous centuries are larger than Mann gave credence. And when the uncertainty of the paleoclimatogical record increases with time, the uncertainty about human contribution is likewise increased. Why? For a reason noted on page 103 of the report: climate model simulations for future climates are tuned to the paleoclimatogical proxy evidence of past climate change.

"Some of these models have been compared against data for past time periods that encompass major changes in forcings and climate responses. ... That these models' simulated climates for those epochs are consistent with proxy evidence lends credibility to their use for attribution of 20th century climate change and projections of future climate change."

With the "hockey stick" now shortened, what is needed is for another McKitrick and McIntyre to inspect the climate models, which form the basis for most of the scary scenarios of future global warming.

Duane Freese is TCS Daily deputy editor.



A fantastic bull's eye strike!

Rather than quibbling
Why don't you report the main conclusion of the NAS report, that global warming is real, caused by human activity, and will have devistating economic consequences if allowed to continue. OK, somebody somewhere got a comma wrong.

Not quite,
Someone, namely MBH98, went significantly beyond where the science would allow, and they were rebutted successfully. The NAS has endorsed the discarding of the Hockey Stick, the central piece of evidence used to popularize the notion of human-engendered climate change.

The second major finding in the report is by re-establishing what was present in the IPCC assessment report main bodies but entirely absent in the summaries for policymakers, namely the uncertainty that surrounds climate change science.

What is the source?

You claim it is in the report, but if you don't provide your source, how can anyone believe you?

Ever hear of footnotes?

Not What the Report Concludes
The authors of the NAS report cited in the first paragraph, and used as the basis of this article, write:

"...the committee finds it plausible that the Northern Hemisphere was warmer during the last few decased of the 20th century than during any comparable period over the preceeding millennium.

"Surface temperature reconstructions for periods prior to the industrial era are only one of multiple lines of evidence supporting the conclusion that climactic warming is occuring in response to human activities..." (pp. 3-4)

For some reason, the author of this article doesn't mention this part of the report. It could be, I suppose, that this part - which is the report's overall conclusion - directly contradicts his point.

The sad and yet oh-so-revealing thing about this sort of dissemblance is that it is utterly shameless.

Mainly because the study did not conclude what you claim.
The NAS did conclude that warming is real. Nobody has ever denied that.

The NAS did not conclude that the warming is man caused.

The NAS never addressed the claim that it will cause devastating economic consequences.

Just how the heck is a few tenths of a degree of heating going to cause devastating economic damages? Especially considering the well documented economic advantages of enhanced CO2?

Definition of plausible - I choose #2 or #3.

1. Seemingly or apparently valid, likely, or acceptable; credible: a plausible excuse.

2. Giving a deceptive impression of truth or reliability.

3. Disingenuously smooth; fast-talking: “Ambitious, unscrupulous, energetic,... and plausible,a political gladiator, ready for a ‘set-to’ in any crowd” (Frederick Douglass).

The NAS commmittee report provided no evidence that humans are causing warming.
I think the above TCS article is reasonably accurate. I came to similar conclusions independently after reading the full NAS Report, Summary, Press Release and listening to the Press Conference.

My commentary on the NAS report is located at the following and subsequent TCS posts:

Re your post:
"Surface temperature reconstructions for periods prior to the industrial era are only one of multiple lines of evidence supporting the conclusion that climactic warming is occuring in response to human activities..." (pp. 3-4)

The NAS commmittee report provided no evidence to support the hypothesis that humans are causing warming. As such, this comment from the Summary was unsubstantiated opinion. It certainly was NOT their overall conclusion, as you state.

Frankly I think the NAS Committee did more than its fair share of dissembling in the Summary, the Press
release and especially the Press Conference. The Report itself was not all that bad.

Interested parties should really form their own opinion by reading the full ~150 page NAS report at:

NAS Report
Since we have been part of the debate, we have preparing our own assessment of the NAS report.

We welcome the National Research Council’s Report, which clarifies that the discussion about the technical qualities of the hockeystick-methodology is insignificant for the overall conclusion that the presently ongoing warming is likely related to elevated greenhouse gas concentrations in the atmosphere. We are pleased to read that the NRC shares our view that the methodology behind the hockeystick is questionable. We stick to our view that the methodology was not sufficiently described when published and independently tested thereafter.

1) We welcome the conclusion of the analysis by the NRC committee, which separates between two issues, namely firstly the claim that the last few decades (the last decade, the year 1998) were unprecedented in their warmth compared to a previous time horizon, and secondly the certainty we place into the published estimates of temperature variations in the past 1000-2000 years.
2) The assessment that the last few decades have exhibit a warming likely beyond the range of natural variations has been made on a variety of scientific findings, of which the Mann et al study was possibly the most publicly “sold” one, but other studies have provided better evidence (“detection and attribution studies”).
3) We share the assessment of the NRC committee that the evidence for unprecedented warming of a single decade or even a single year in times prior to 1500, or so, is stretching the scientific evidence too far. However, this was the key claim made in the contested 1998-“nature” and 1999-GRL-papers by Mann et al.
4) With respect to methods, the committee is showing reservations concerning the methodology of Mann et al.. The committee notes explicitly on pages 91 and 111 that the method has no validation (CE) skill significantly different from zero. In the past, however, it has always been claimed that the method has a significant nonzero validation skill. Methods without a validation skill are usually considered useless.
5) Other independent efforts (e.g., inversion of borehole temperatures) to reconstruct past temperatures find different temperature ranges albeit qualitative agreement. These quantitative differences underline the methodological limitation of the Mann et al approach, which are described in the sections 9 and 11 of the NRC report.
6) We welcome the major conclusion of the report that further scientific efforts are needed to sort out a variety of problems with respect to methods and data ; also the uncertainty must be assessed in a more objective manner. Thus, the public perception that the hockeystick as truthfully describing the temperature history was definitely false.
7) We find it disappointing that the method of Mann et al. was not sufficiently described in the original publication, and thus not peer-reviewed prior to publication, and that no serious efforts were made to allow independent researchers to check the performance of the methods and of the data used.

Hans von Storch, Eduardo Zorita and Fidel Gonzalez-Rouco

New York Times goofs again
Anyone notice the New York Times story of June 20th, "Next Victim of Warming: The Beaches"?

Cornelia Dean wrote; "In 2001, the Intergovernmental Panel on Climate Change, convened by the United Nations, said that the rise in sea levels was accelerating."

Ms. Dean could not be more mistaken. The IPCC actually said the following in 2001-

"No significant acceleration in the rate of sea level rise during the 20th century has been detected"

Do you think the N.Y. Times will run a correction?

B.4 Observed Changes in Sea Level

Changes during the instrumental record

"Based on tide gauge data, the rate of global mean sea level rise during the 20th century is in the range 1.0 to 2.0 mm/yr, with a central value of 1.5 mm/yr (the central value should not be interpreted as a best estimate). (See Box 2 for the factors that influence sea level.) As Figure 6 indicates, the longest instrumental records (two or three centuries at most) of local sea level come from tide gauges. Based on the very few long tide-gauge records, the average rate of sea level rise has been larger during the 20th century than during the 19th century. No significant acceleration in the rate of sea level rise during the 20th century has been detected. This is not inconsistent with model results due to the possibility of compensating factors and the limited data."

11.6.1 Observations of Current Rates of Global-averaged and Regional Sea Level Change

"Sections and 11.4 reveal significant uncertainty in the analysis of 20th century sea level change.”

Republican Support Lengthened
Global Warming on Main Street
Business Week, June 27, 2006

Wall Street is getting the climate-change message loud and clear. That's because corporate giants such as Dow, BP, Shell, General Electric, Wal-Mart, and DuPont have accepted the scientific consensus that global warming is real and that human activity contributes to it...

...A shift is also occurring among Republicans in Congress. Representative Bob Inglis, a South Carolina Republican who heads the U.S. House Science Research subcommittee, says "There are more and more Republicans willing to stop laughing at climate change and who are ready to get serious about reclaiming their heritage as conservationists."

In addition to Inglis, the list of Republicans now paying serious attention to global warming includes senators Pete Domenici of New Mexico, the chairman of the chamber's Energy Committee, Mike DeWine of Ohio, Lindsey Graham of South Carolina, and Representative Jim Leach of Iowa...

Detected v. predicted v. possible/plausible
First, they _dd_ note a rise in sea level, not large, but measurable. Second, the 20th is not the 21st century. The problem is increased warming may raise sea levels substantially if the Greenland and/or Antarctic caps lose water.And this would be a problem.

The report does in fact offer such evidence
It's in chapter 10 "Climate Forcings and Climate Models." It notes (page 94) that "climate model simulations indicate that solar and volcanic forcings together couldhave produced periods of relative warmth and cold during the pre-industrial period of the last 1,000 years. However, anthropogenic greenhouse gas increases are needed to simulate late 20th century warmth."

The text of Chapter 10 presents the case for this conclusion in detail,

A "measurable rise" is natural and expected. Over the course of earth's history it's natural for the polar caps to be melting.

Expected, maybe. Natural, no
The latest 20th-21st century increase in temperature has been traced to human inputs. If the greenland cap mets-- and it's gettng pretty slushy according to a piece in the LA Times early this week - it's pretty clearly not natural.

Read the LA Times story at:,1,1483560.story

Expected, yes Natural, yes
Try to find a copy of National Geographic, Nov. 1976

page 607:
"We live in an unusual epoch: today the polar regions have large ice caps, whereas during most of the earth's history the poles have been ice-free." National Academy of Sciences, 1975

p 590:
"The climates of the earth have always been changing, and they will doubtless continue to do so in the future. How large these future chnages will be, and where and how rapidly they will occur, we do not know." National Academy of Sciences, 1975

Read the latest report, the subject of the essay
It identifies humans as the cause of the latest spate of warming.

As for the fact that the poles have been ice-free before: sure. The thing is,there weren't large coastal cities to submerge the last time they melted.

Finally, as for the "we do not know," -- science has progressed in the 31 years since 1975. Please look at the NAS's more recent statements.

And regarding "natural"
Forest fires occurred naturally long before humans learned to use fire. That doesn't imply that humans now can't start forest fires.

Slushy Greenland & the LA Times
Hmmm, according to the most nightmarish of forecasts, if (and that's a big if), current warming trends continue, the ice cap would melt in about 10,000 - 14,000 years.

I love the alarmist sub head of the LA Times article - "If the ice thaws entirely, sea level would rise 21 feet."
It's enough to make any uninformed reader scared sh!tless.

So, using the LA Times numbers and assuming a complete meltdown in the shorter 10,000 year timeframe, we would sea a rising sea level of 2.52 inches every 100 years. Over a 14,000 year period, we would see an increase of 1.8 inches every hundred years.

Regarding the larger influencer on rising/lowering sea levels, the Antarctic, there is no definitive proof that the Antarctic ice sheets are cumulatively melting or growing (the larger East Sheet has been shown to be growing while the West is decreasing).

What forecast is this??
The ice doesn't all have to melt to be a problem, and current trends could become much more marked quite quickly if positive feedback loops develop.

Perhaps this sentence from the Times story will sound reassuring:

>From cores of ancient Greenland ice extracted by the National Science Foundation, researchers have identified at least 20 sudden climate changes in the last 110,000 years, in which average temperatures fluctuated as much as 15 degrees in a single decade.

I missed the statement in the Times story that "if (and that's a big if), current warming trends continue, the ice cap would melt in about 10,000 - 14,000 years. "

The point of the Times story is that warming trends aren't "continuing," they're accelerating. If you have different information, maybe let the Times reporter know.

The Ice Caps Are Melting! The Ice Caps Are Melting!
So says the revised Chicken Little story as taught to our little rug-rats these days.

RINOs galor
Sure...this are the same folks who have sold out the Conservative Base on all the other issues of import to it. Big deal.


The key in your quote from the report, and I paraphrase, is that the models need AG gas increases to simulate late 20th century warmth. This is not the same as saying that AG gas increases are necessary or sufficient to explain the warming. You've heard of faint praise?

Yes, Shameless You Most Certainly Are
The reports hitherto given do not support what you a priori desire them to, and there is no consistency in the view of people such as yourself. THAT is the point of the author.

Temperature Fluctuations

For most of the last 110,000yrs the earth was in an ice age, and, this is when these large temp fluctuations occured. The temps in the current interglacial have been more stable.

i know nuttin
How does one separate the effects of CH4 comming out of the arctic tundra from the effect of man made emissions?

How do the models distinguish between geologic sources and non geologic sources?

How do the models monitor changes to geologic sources?

Considering that most of them are deep under the ocean?

What is the standard error rate for the best models?

How would one go about making such a determination?

I know model builders who live or die on tolerances.

How do the models you are talking about control for tolerance?

oh yeah, isn't the word climatic, as opposed to "climactic"?
Or is accuracy and precission a relative subjective blue collar kind of a thingy?

just curious..

What the Models, Scientists and Al Gore WON'T Tell You
That even if humans were to somehow reduce their gh gas emissions to zero tomorrow and keep it that way for a hundred years, the climate won't change with devastating consequences for humanity anyway!

Even if this particular warming trend is exclusively human-caused (and that's a big if), there is not one shred of scientific data that says the warming trend will decrease or reverse itself if we reduce our greenhouse gas emissions.

We all know that the earth's climate has been much warmer -and much colder - in the past than it is now. What scientific "consensus" is there that the Earth won't return to either of those climatic conditions at some point in the future?

We live in an environment that is constantly changing. It is just plain common sense that we need to adapt to changing conditions.

It's par for the course that politicians will buy into this quixotic scheme - this does potentially mean taxpayer-funded "anti-global warming" pork programs will be initiated and patronage jobs will be created for their constituents - but it is truly unfortunate that highly-regarded "scientists" are so willing to prostitute their credibility by selling us an utterly unproven snake oil "solution" to that which science itself tells us is inevitable - change.

no need for facts
The GW debate doesn't need to follow the scientific method because liberals, who think they are smarter than normal people, figure we should just follow the 'litany' without question. After all, as they say; "the truth doesn't matter, we're out to save the world".

were stable
human activity has destabilized

I don't think the National Academy of Sciences is part of the Chicken Little story
Did someone tell you they were wrong about this?

Let the NAS speak for itself
and be sure to send them email about how what they say is dubious.

I quoted the report, verbatim
You want it to say something different? Talk to the people who wrote it.

Tell the NAS about the scientific method, since you're such an expert
Be sure to tell them that they are liberals and believe the truth doesn't matter. See what they say.

I'll tell them...
that they really have a bad attitude for so called scientists. Did you notice their quote at the top? "We have 25 or so years invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it?" Do you think that is the right attitude to science? Or could it be that scientists can also have vested interests? Could they really be just another biased special interest group. Many liberals can't face that.

Who funds the NAS?
It is a private, non-profit self sustaining organization. Where do they get their money. Anyone know?

85 percent comes from the federal government

But the rest obviously comes from the tree-hugger worldgovernment socialist conspiracy, right?

Learning without thought is labor lost; thought without learning is perilous
"The majority of mistakes in ordinary thinking (outside of technical matters) are mistakes in perception. Our traditional emphasis on logic does little for perception. If the perception is inadequate then no amount of excellence in logic will make up for that deficiency." ~ Edward de Bono

Greenland has been warmer, without man's help
Why is this time different? Other than your religion requires you to believe so?

Decadal oscillations
Back in the 30's and 40's, Greenland and the arctic were warmer than today. In a few years, when the we switch back to the cold phase, Greenland will start cooling again.

I believe the oceans
are rising faster than that, about 18 cm./century, and they have been doing so for the past several thousand years. Isostatic rebound from the Wisconsin/Wurm ice advance.

So this is already a larger factor than any melting of the Greenland ice sheet even if it happens.

During the last 100 years, the earth has warmed by about 0.2%.
During the last 100 years, the sun has grown hotter by o.17%.
A hotter sun deflects cosmic radiation away from the earth, resulting in fewer clouds. This warms the earth, but the actual amount is still in dispute.
There is lots of evidence that Urban Heat Island (UHI) affect has not been fully accounted for in the ground based sensor records.

Selective data
Is or is it not true that a frequent comparison year for Greenland is 1992? If so, then Greenland is always melting by comparison with a single, untypical year not reflective of long term or average conditions.

And Greenland can also be much warmer, with man's help
and the consequences for humans would be considerable. This is not "religion," it's a scientific fact. What religion are you following that requires you to deny it?

No, they were not. You're making this up
What's your source for this? Oh, I forgot: you don't use sources.

If a substantial portion of the Greenland ice sheet melts, no big deal?
Isostatic rebound or no isostatic rebound, that amount of extra water going into the ocean will make a difference.

I really think that scientists studying the Greenland ice sheet understand what melting is.
What's your source for the 1992 number? Do you really think that the statements in, for example, the LA Times story by the scientists are based on elementary misunderstandings and "selective data?"

That's right, no big deal,
because with the rebound effect, essentially the oceans get deeper. It's why there's about a yard of new beach in Hudson's Bay every year.

Part of the problem with these things is scale. In the case of the Antarctic ice sheets, I recall reading a paper by Phil Jones about five years ago which showed that the response time to changes in sea level for the ice shelves was about 78,000 years.

Selective data
is a very common problem in certain research fields. It is particularly glaring in health studies on things like EMF, radiation effects and cancer, the recent issue over MMR causing autism. In the case of MMR, it's clear that the distortion was deliberately misleading. Another particularly outrageous use of selected statistics was the early 1990s study in Britain on the transmission of leukemia to children whose parents worked at Sellafield.

Fact is, some disciplines are more subject to it than others in areas where they cannot demonstrate clear cause and effect and hence must support a theory by a statistical association. What's happened over the years is that the strength of the association for a claim to have merit has been greatly reduced over the years.

Does it happen universally? No, certainly not. But all too many attention-grabbing headlines have been found to be based on shoddy measurement or shoddy statistics. The cold fusion fiasco in the late 1980s is a good example. What the simple technical explanation for this is that Pons and Fleischman bungled their calorimetry. What they'd in fact done was nothing more interesting than a battery effect. In their case the failure might be deemed innocent, except that they announced their results to the press before completing their technical paper.

too bad most of Greenland is getting colder
despite the LAT lies of the day.

And your evidence that actions by man is causing this warming is??????

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