The Week That Was (July 15, 2006) brought to you by SEPP

New on the Web: Some oldies from J. Gordon Prather on recycling nuclear fuel -- and still worth reading. And there may be a bright future for thorium as a nuclear fuel (Item #1).

The Supreme Court overrules the government on wetlands - but provides no final answers (Item #2). The National Academy overrules EPA on dioxins (Item #3). The Supremes will rule on Massachusetts vs EPA on CO2 control -- after the Circuit Court ruled against Mass. (Item #4).

After a diplomatic NAS report fails to announce the end of the Hockeystick explicitly, we now witness its final burial -and it's about time (Item #5): First, scientific results from proxies, including tree rings and glaciers, pointing to a Medieval Warm Period 1000 years ago that was a least as warm as the 20th century. Then, accounts in the Canadian and US press of the Hockeystick war. And finally, the Wegman report, described in the WSJ of July 14, puts the final nail in the coffin.

TWTW has written a great deal about the Hockeystick battles. This wrap-up says it all.
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Major scientific journals routinely turn down papers skeptical of Anthropogenic Global Warming. Here is a gem from Nature, received by a very distinguished friend of ours. Was it computer-generated?

"In the present case, while we have no doubt that your findings will be of inherent interest to fellow specialists, I regret that we are unable to conclude that the paper provides the dynamics of sort of firmly supported conceptual advance in scientific understanding of the dynamics of annual variations in atmospheric levels of carbon dioxide that would be likely to excite the immediate interest of researchers in a broad range of other disciplines. We therefore feel that the present paper would find a more appropriate outlet in a specialist journal, rather than Nature"
[courtesy Climatesceptics email]
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And a decree:
Decreed: The averages for no hour, day, month, or year may vary more than 0.01 sigma from the established norm for any locality on Earth. Ever! The sun, therefore, is hereby commanded to stop varying its output. Cloud cover, directions and velocities of winds, water vapor content, etc. shall remain constant for each locale. Stasis is the only acceptable operation permitted for nature. This rule applies in all climes at all times. Violations shall be harshly dealt with.

/s/ by royal elitist decree
Al Gore, Chief pseudo-scientist
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1. Thorium Nuclear Reactor Designs Advancing

FuturePundit, 22 June 2006
http://www.futurepundit.com/archives/003536.html

The use of thorium to power nuclear reactors holds out the prospect of a huge reduction in nuclear wastes, a nuclear fuel cycle that is much more proliferation resistant, lower costs, and a fuel that is many times more plentiful than uranium. Australian science writer Tim Dean examines the prospects for thorium reactors in a recent article and finds two avenues of technological advance that might make thorium powered nuclear reactors feasible.

(1) The more immediately promising approach uses a mixture of thorium with other radioactive materials.
http://www.cosmosmagazine.com/node/348
The main stumbling block until now has been how to provide thorium fuel with enough neutrons to keep the reaction going, and do so in an efficient and economical way.

In recent years two new technologies have been developed to do just this.

One company that has already begun developing thorium-fuelled nuclear power is the aptly named Thorium Power, based just outside Washington DC. The way Thorium Power gets around the sub-criticality of thorium is to create mixed fuels using a combination of enriched uranium, plutonium and thorium.

At the centre of the fuel rod is the 'seed' for the reaction, which contains plutonium. Wrapped around the core is the 'blanket', which is made from a mixture of uranium and thorium. The seed then provides the necessary neutrons to the blanket to kick-start the thorium fuel cycle. Meanwhile, the plutonium and uranium are also undergoing fission.

The primary benefit of Thorium Power's system is that it can be used in existing nuclear plants with slight modification, such as Russian VVER-1000 reactors. Seth Grae, president and chief executive of Thorium Power, and his team are actively working with the Russians to develop a commercial product by the end of this decade. They already have thorium fuel running in the IR-8 research reactor at the Kurchatov Institute in Moscow.

The potential to use existing reactors to burn thorium lowers the barrier to use of thorium. Success in existing reactors could catalyze the construction of new reactors designed to use thorium from their start.

(2) He also goes over Carlo Rubbia's proposal to use a particle accelerator to shoot a stream of protons into a thorium reactor.

AN ALTERNATIVE DESIGN does away with the requirements for uranium or plutonium altogether, and relies on thorium as its primary fuel source. This design, which was originally dubbed an Energy Amplifier but has more recently been named an Accelerator Driven System (ADS), was proposed by Italian Nobel physics laureate Carlos Rubbia, a former director of one of the world's leading nuclear physics labs, CERN, the European Organisation for Nuclear Research.

An ADS reactor is sub-critical, which means it needs help to get the thorium to react. To do this, a particle accelerator fires protons at a lead target. When struck by high- energy protons, the lead releases neutrons that collide with nuclei in the thorium fuel, which begins the fuel cycle that ends in the fission of U- 233.

Governments should accelerate research into new nuclear reactor designs that promise to lower wastes and reduce costs.
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2. Supreme Court Rules on EPA Regulation

The Supreme Court ruled 5-4 today that regulators may have misinterpreted the federal Clean Water Act when they refused to allow two Michigan property owners to build a shopping mall and condos on wetlands they own, the Associated Press reports. The court voided rulings against June Carabell and John Rapanos, who wanted to fill wetlands they owned near Lake St. Clair in Macomb County, Michigan. Carabell wanted to build condos on wetlands she owns about a mile from the lake. Rapanos wanted to put a shopping mall on his property, which is about 20 miles from the lake.

According to Tim Lynch and Mark Moller, authors of Cato's friend-of-the-court brief in support of Mr. Rapanos, the Court reached the right decision: "If the government can regulate any land from which water occasionally drains, no matter how speculative the effect of this drainage on navigable water, wetlands law gives it almost limitless jurisdiction over private property, except perhaps in the heart of the Mojave desert. In essence, the federal government's reading of the Clean Water Act would turn the EPA into a vast national zoning board."
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3. EPA Dioxin Assessment Understates Uncertainties, May Overstate Cancer Risk

July 11 -- EPA comprehensively reviewed the scientific literature in a draft assessment of the health risks of dioxin, but it did not adequately quantify the uncertainties associated with the risks, nor did it adequately justify the assumptions used to estimate them, says a new National Research Council report. Using different assumptions may result in a lower estimated cancer risk for humans exposed to low doses of dioxin and related compounds

http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=11688

The committee took issue with EPA's decision to rely solely on a "linear" model that assumes the risk of cancer is directly proportional to dose at all levels of exposure, including the levels found in the environment, which are generally much lower than those shown to cause cancer in animals. Such an approach usually results in higher risk estimates than those based on nonlinear assumptions, where biological responses do not vary proportionally with dose.

EPA said there was a lack of data to support a nonlinear approach, but the committee said that compelling new animal data from the National Toxicology Program -- released after EPA completed its reassessment -- when combined with substantial evidence that dioxin does not directly damage DNA, is now adequate to justify the use of nonlinear methods for estimating cancer risk at relatively low levels of exposure. Such a nonlinear model would result in a lower estimate of risk.

The report recommends that EPA estimate cancer risk using both a nonlinear and linear model and describe the strengths and weaknesses of each.

-----------------------
Read: EPA's Never Ending Dioxin Scare
Junk Science

www.foxnews.com/story/0,2933,203421,00.html
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4. Global Warming and the Courts
NYT July 8, 2006 Editorial

In a move that has caused both delight and apprehension among those who worry about global warming, the Supreme Court has agreed to rule next fall on whether the Environmental Protection Agency has the authority under the Clean Air Act to regulate carbon dioxide and other greenhouse gases. The case is among the most important environmental disputes ever to come before the court.

The outcome will have much to say about whether the country will be able to act more aggressively on a problem with potentially grave consequences for the earth and its inhabitants. It could also determine whether states that have acted on their own to limit global warming emissions from vehicles - as California and 10 other states have done - can proceed without fear of a federal veto.

President Bush has advanced many reasons for not pressing for strong controls on greenhouse gas emissions from vehicles, power plants and other industrial sources. But his ace in the hole has been the claim that the federal government has no authority to regulate greenhouse gases.

The case turns largely on a simple reading of the Clean Air Act. The administration argues that the act mentions carbon dioxide only in passing, and that if Congress had been truly worried about global warming it would have given the gases that cause it more emphasis and instructed the E.P.A. to take aggressive steps to control them, as it did with sulfur dioxide and other pollutants. The administration argues further that the science on global warming is too "uncertain" to justify anything more than a voluntary effort to deal with it.

The plaintiffs - a formidable collection of state governments and environmental groups - argue that the plain language of the Clean Air Act gives the government jurisdiction over "any air pollutant" that threatens "public health or welfare" and, further, that "welfare" specifically includes effects on climate and weather. This interpretation of the act was first set forth by President Clinton's E.P.A. and stood as agency policy until Mr. Bush reversed it (without consulting his own E.P.A.) in 2001.

As for the science that the administration finds so shaky, the plaintiffs will argue that the science has grown steadily more persuasive since the Clean Air Act was last revised in 1990; that the administration has cherry-picked arguments about details while ignoring the vast preponderance of the evidence; and that the consensus among mainstream scientists - a consensus reinforced by a recent National Academy of Sciences report - is that the earth is inexorably heating up and that industrial emissions are largely responsible.

This is a case of global importance, not least because America's failure to act decisively has discouraged the rest of the world from acting decisively. On the face of it, the law plainly gives the government the power to regulate greenhouse gases. A ruling that tells the administration that it has that power does not mean that it will actually use it. But it will no longer be able to hide behind a legal fiction.
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A Court Rules Prudently... for Now
By Joel Schwartz, 19 Jul 2005

In the latest setback for global warming activists, the federal Court of Appeals for the DC Circuit ruled last Friday that the Clean Air Act does not require the Environmental Protection Agency to regulate greenhouse gas emissions from motor vehicles. The Court did not decide whether the Clean Air Act (CAA) gives EPA the authority to regulate greenhouse gases (GHG), but merely that, in choosing not to regulate GHGs, EPA made a policy call that was within its legitimate legal discretion.

The Court's ruling came in response to a petition from a dozen states' attorneys general, ten environmental groups, and three cities, who are attempting to mandate national GHG reductions through the courts. The goal is to effectively implement the Kyoto Protocol without the approval of Congress or the President.

The ruling is good news for those who believe GHG regulations would harm Americans' prosperity, health, and freedom. However, because the Court's ruling was on such narrow grounds, the victory is cause for only a brief celebration. The Court did not address the fundamental issues of whether EPA has legal authority to regulate GHG emissions and whether the Petitioners have standing to file suit in the first place. Both questions are likely to return in some future case.

Does EPA have the authority to regulate GHGs? We won't know for sure until a court rules on the subject. But there are at least two issues that must be decided. First, are carbon dioxide (CO2) and other GHGs "air pollutants" for the purposes of the Clean Air Act? Second, the CAA requires EPA to regulate air pollution that threatens public health and welfare. Does that authority include perceived threats due to global climate change?

Title II of the Clean Air Act gives EPA the authority to regulate air pollution from motor vehicles. Section 202(a)(1) states:

The Administrator shall by regulation prescribe . . . standards applicable to the emission of any air pollutant from any class or classes of new motor vehicles or new motor vehicle engines which in his judgment cause, or contribute to, air pollution which may reasonably be anticipated to endanger public health or welfare.

Section 302(g) of the Act defines an "air pollutant" as

any air pollution agent or combination of such agents, including any physical, chemical, biological, radioactive...substance or matter which is emitted into or otherwise enters the ambient air.

The attorneys general and environmentalists pursuing the case asked the court to interpret the term "air pollutant" in its broadest conceivable meaning. But by the Petitioners' definition water vapor is an air pollutant, as it "enters the ambient air" due to the same human activities that emit CO2 and air pollution. The fact that the Petitioners' definition of air pollution leads to such an absurd result suggests that it couldn't have been what Congress intended when it adopted the nation's clean air laws.

Congress presumably used the term "air pollution" in its ordinary meaning -- something that contaminates or fouls the air, making it harmful to breathe. CO2, like oxygen, nitrogen, and water, is not an air pollutant under this definition. Indeed, for the last 40 years the goal of automobile emissions control has been to achieve ever-greater efficiency in converting air pollutants -- carbon monoxide, hydrocarbons, and oxides of nitrogen -- into CO2, water, and nitrogen exactly because the latter three substances are not air pollution.

A number of other features of the Clean Air Act suggest that Congress did not intend the Act's provisions to apply to GHGs. First, the CAA's system for reducing air pollution, as detailed in Title I of the Act, is premised on the idea that air pollution problems are regional in nature and should be addressed through state and local planning to bring "non-attainment areas" into compliance with federal standards. Furthermore, there is a relatively rapid response between reductions in air pollutants and their precursors and ensuing reductions in ambient pollution levels. In contrast, CO2 diffuses globally and current reductions in CO2 take decades to have an effect on ambient CO2 levels.

Second, the "criteria" air pollutants -- ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, lead, and particulate matter -- are mentioned many times under many specific regulatory provisions of the Act. The CAA also lists 188 "hazardous air pollutants" and prescribes that they will be controlled through "maximum achievable control technology."

On the other hand, CO2 is mentioned only a few times, and never under a regulatory provision. In his dissenting opinion, Judge David Tatel, who would have required EPA to regulate motor-vehicle GHG emissions, highlighted the fact that CO2 is explicitly listed as an air pollutant in Section 103(g) of the CAA. But this section merely requires EPA to do research on "non-regulatory" strategies for reducing emissions from "stationary sources." Furthermore, Section 103(g) also cautions "Nothing in this subsection shall be construed to authorize the imposition on any person of air pollution control requirements."

Third, Congress has given the National Highway Traffic Safety Administration (NHTSA) sole authority to set motor-vehicle fuel-economy (CAFE) standards. Under its legislative mandate, NHTSA must consider "technological feasibility, economic practicability, the effect of other motor vehicle standards of the Government on fuel economy, and the need of the United States to conserve energy." These factors reflect tradeoffs among "environmental [policy]...engineering design, safety, national energy policy, international competitiveness, and trade."[1]

EPA, unhindered by these tradeoffs, would require much larger CO2 reductions than required by CAFE, rendering NHTSA's authority over fuel economy meaningless. Presumably, if Congress intended EPA to be able to override NHTSA's fuel-economy authority, it would have expressly said so. But Congress did just the opposite. During debate on the 1990 Clean Air Act Amendments, Congress specifically considered and rejected a bill (S. 1630; Baucus) that would have required EPA to set CO2 emission standards for motor vehicles.[2]

Fourth, Congress generally creates specific CAA authorities when it wants EPA to regulate particular emissions. For example, the CAA includes specific authority to regulate ozone-depleting substances and specific requirements to reduce emissions of expressly listed hazardous air pollutants. But Congress has never created similar express authority regarding GHG emissions.

We depend on fossil-fuel energy for virtually every aspect of our lives, and CO2 emissions are intrinsic to fossil-fuel energy. The power to regulate CO2 emissions is therefore the power to regulate just about all human activity. It seems inconceivable that Congress could have intended to give EPA such extraordinary power with a few vague statements in an air pollution law.

Nevertheless, while it might seem to us out in the real world that Congress hasn't given EPA authority over GHGs, the legal world often follows arcane rules that have no counterpart in everyday experience. Call it the quantum mechanics of jurisprudence. Words and phrases have only probabilistic meanings until a court makes a ruling and collapses the judicial wave function.

The Supreme Court recently ruled that the federal government can regulate medical marijuana under the federal interstate commerce power, even if the marijuana never crosses state lines and no money changes hands, and that the Fifth Amendment's "public use" clause allows governments to seize private property from some people and transfer it to other, better-connected people.

With decisions like these, it isn't too difficult to imagine a court coming down in favor of GHG authority for EPA. Indeed, David Tatel, the dissenting judge in last Friday's decision, thought EPA's authority to regulate CO2 was a slam dunk.

Opponents of GHG regulations should also be concerned that EPA has shown itself to be a somewhat lax defendant. The attorneys general and environmentalists who petitioned for GHG regulations submitted declarations by climate scientists predicting all manner of future harms -- flooding, drought, infectious disease, heat-related mortality -- due to EPA's failure to regulate emissions. EPA did not attempt to rebut these claims or to put forward a more realistic view of the weight of the climate-change evidence. EPA also weakened its defense by refusing to put forth a definition of air pollution.

Proponents of GHG regulation are tenacious and single-mindedly committed to their goals. But the Bush Administration is not single-mindedly committed to preventing GHG regulation. Rather, various factions in the Administration pursue, with varying degrees of vigor, a number of different and sometimes contradictory goals at the same time.

Many career EPA employees no doubt want very much to regulate GHG emissions, and political appointees can exert only so much control over the career staff. The Bush Administration itself, whether for reasons of politics or ignorance, has also given intellectual ground to alarmists in the climate change debate. EPA has good bureaucratic reasons for not wanting to define what constitutes an air pollutant, as this could constrain the agency's actions in other arenas besides climate change. Better to leave the definition vague and thereby maintain maximum flexibility and discretion. Because of these conflicts, regardless of who is in the White House, the best legal and scientific arguments against GHG regulations will continue to come from outside the government.

The power to regulate greenhouse gases is the power to ration energy and thereby exert great power over people's quality of life. Hopefully, the courts will continue to find that current law does not grant EPA authority over GHG emissions. But given the vagaries of judicial decisions about complex laws like the Clean Air Act, Americans' best protection against energy rationing may lie with clearer statutory direction from Congress.

[1] From the Senate Report on the legislation (S. Rep. No. 101-228, 439, 1990 U.S.C.C.A.N. 3385, 3920), cited in Congressman John Dingell's Amicus Brief in the case. [2] 136 Congressional Record 6479 (1989), cited in Dingell's Brief.
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5. The final end -and burial - of the Hockeystick

A. The Medieval Warm Period was global and at least as warm as the 20th century

Medieval Warm Period (Solar Influence - Other) -- Summary http://www.co2science.org/scripts/CO2ScienceB2C/subject/s/summaries/mwpsolarother.jsp

Clues to past climatic conditions may be found in a wide variety of proxy data pertaining to many more things than simply temperature and precipitation. In the paragraphs that follow, we review the findings of some recent studies of such data that tell us much about the genesis and demise of the Medieval Warm Period, along with what these things imply about the planet's current warmth.
http://www.co2science.org/scripts/CO2ScienceB2C/articles/V9/N6/C1.jsp

Maasch et al. (2005) examined changes in eight well-dated high-resolution non-temperature histories covering the past two millennia: (1) K+ concentrations obtained from the GISP2 ice core in Greenland, (2) Na+ concentrations derived from the Siple Dome ice core in Antarctica, (3) percent Ti present in an ocean sediment core retrieved from the Cariaco Basin off the coast of Venezuela, (4) Fe intensity from a marine sediment core extracted near the coast of mid-latitude Chile, (5) oxygen isotope fractions from Punta Laguna near the Yucatan, (6) carbon isotope data from a speleothem in Makapansgat, South Africa, (7) percent of shallow water diatoms found in a sediment core taken from Lake Victoria, and (8) past levels of Lake Naivasha in equatorial Africa. They then compared these histories with a similar history of atmospheric 14C to ascertain if any solar influence might have operated on these parameters. This comparison revealed that over the past 2000 years there had been, in the words of the researchers, a "strong association between solar variability and globally distributed climate change [our italics]," and they say that this "remarkable coherence" among the data sets was particularly noticeable in the Medieval Warm Period to Little Ice Age transition.
In a similar vein, but covering the entire period of the current interglacial or Holocene,
http://www.co2science.org/scripts/CO2ScienceB2C/articles/V7/N51/C3.jsp

Mayewski et al. (2005) examined some fifty globally distributed paleoclimate records in search of evidence for what they call rapid climate change (RCC). This terminology is not to be confused with the rapid climate changes typical of glacial periods, but is used in the place of what the sixteen researchers call the "more geographically or temporally restrictive terminology such as 'Little Ice Age' and 'Medieval Warm Period'." Hence, RCC events, as they also call them, are multi-century periods characterized by extremes of various climatic properties, rather than the much shorter periods during which the changes that produced them took place.

Mayewski et al. identified six RCCs during the Holocene: 9000-8000, 6000-5000, 4200-3800, 3500-2500, 1200-1000 and 600-150 cal yr BP, the last two of which intervals are the "globally distributed" Medieval Warm Period and Little Ice Age, respectively. In speaking further of these two periods, they say that "the short-lived 1200-1000 cal yr BP RCC event coincided with the drought-related collapse of Maya civilization and was accompanied by a loss of several million lives (Hodell et al., 2001; Gill, 2000), while the collapse of Greenland's Norse colonies at ~600 cal yr BP (Buckland et al., 1995) coincides with a period of polar cooling."

With respect to the causes of these and other Holocene RCCs, the international team of scientists says that "of all the potential climate forcing mechanisms, solar variability superimposed on long-term changes in insolation (Bond et al., 2001; Denton and Karlen, 1973; Mayewski et al., 1997; O'Brien et al., 1995) seems to be the most likely important forcing mechanism." In addition, they note that "negligible forcing roles are played by CH4 and CO2," and that "changes in the concentrations of CO2 and CH4 appear to have been more the result than the cause of the RCCs."
In another study that shows the pervasiveness of the Medieval Warm Period-Little Ice Age type of cyclical climate change,
http://www.co2science.org/scripts/CO2ScienceB2C/articles/V5/N13/C3.jsp

de Garidel-Thoron and Beaufort (2001) reconstructed a 200,000-year history of primary productivity in the Sulu Sea north of Borneo, based on measured abundances of the coccolithophore Florisphaera profunda in a giant piston core. Three time-slices of this core were explored in detail in order to determine high-frequency cycles in the primary production record: one from 160 to 130 ka, one from 60 to 30 ka, and one from 22 to 4.1 ka. The finest-scale repeatable feature observed in all three time-slices was a climate-driven primary production oscillation that had a mean period of approximately 1500 years. With respect to this cycle, they say that its occurrence in the three different time-slices is suggestive of "a common origin and an almost stationary signal across different climatic conditions." They also point out the primary production cycle's similarity to the 1470-year temperature cycle observed by Dansgaard et al. (1984) in the Camp Century d18O ice core record, the ~1500-year d18O and chemical markers cycles observed by Mayewski et al. (1997) in the Summit ice core, the 1470-year climate cycle found by Bond et al. (1997) in North Atlantic deep-sea cores, and the 1500-year climate cycle found by Campbell et al. (1998) in an Alaskan lake. These and other observations led them to suggest that there is also "a common origin" for the documented cyclicity in the climates of both high and low latitudes, which Bond et al. (2001) associated with variable solar activity.

In light of the findings of these many multi-parameter analyses, it is becoming ever more clear that the millennial-scale oscillation of climate that has reverberated throughout glacial and interglacial periods alike is indeed the result of similar-scale oscillations in solar activity. Consequently, Mayewski et al. (2005) suggest that "significantly more research into the potential role of solar variability is warranted, involving new assessments of potential transmission mechanisms to induce climate change and potential enhancement of natural feedbacks that may amplify the relatively weak forcing related to fluctuations in solar output." We couldn't agree more, for until these mechanisms have been elucidated to everyone's satisfaction, the world's climate alarmists will continue to ignore the mountains of evidence that link millennial-scale climate cycles with similar solar cycles, and they will push ever harder for the adoption of wrong-headed energy policies to restrict anthropogenic CO2 emissions to the serious detriment of man and nature alike.

References
Bond, G., Kromer, B., Beer, J., Muscheler, R., Evans, M.N., Showers, W., Hoffmann, S., Lotti-Bond, R., Hajdas, I. and Bonani, G. 2001. Persistent solar influence on North Atlantic climate during the Holocene. Science 294: 2130-2136.
Bond, G., Showers, W., Chezebiet, M., Lotti, R., Almasi, P., deMenocal, P., Priore, P., Cullen, H., Hajdas, I. and Bonani, G. 1997. A pervasive millennial scale cycle in North-Atlantic Holocene and glacial climates. Science 278: 1257-1266.
Buckland, P.C., Amorosi, T., Barlow, L.K., Dugmore, A.J., Mayewski, P.A., McGovern, T.H., Ogilvie, A.E.J., Sadler, J.P. and Skidmore, P. 1995. Bioarchaeological evidence and climatological evidence for the fate of Norse farmers in medieval Greenland. Antiquity 70: 88-96.
Campbell, I.D., Campbell, C., Apps, M.J., Rutter, N.W. and Bush, A.B.G. 1998. Late Holocene ca.1500 yr climatic periodicities and their implications. Geology 26: 471-473.
Dansgaard, W., Johnsen, S.J., Clausen, H.B., Dahl-Jensen, N., Gundestrup, N. and Hammer, C.U. 1984. North Atlantic climatic oscillations revealed by deep Greenland ice cores. In: Hansen, J.E. and Takahashi, T. (Eds.), Climate Processes and Climate Sensitivity, American Geophysical Union, Washington, DC, pp. 288-298.
de Garidel-Thoron, T. and Beaufort, L. 2001. Millennial-scale dynamics of the East Asian winter monsoon during the last 200,000 years. Paleoceanography 16: 1-12.
Denton, G.H. and Karlen, W. 1973. Holocene climatic variations: their pattern and possible cause. Quaternary Research 3: 155-205.
Gill, R.B. 2000. The Great Maya Droughts: Water, Life, and Death. University of New Mexico Press, Albuquerque, New Mexico, USA.
Maasch, K.A., Mayewski, P.A., Rohling, E.J., Stager, J.C., Karlén, W., Meeker, L.D. and Meyerson, E.A. 2005. A 2000-year context for modern climate change. Geografiska Annaler 87 A: 7-15.
Mayewski, P.A., Meeker, L.D., Twickler, M.S., Whitlow, S., Yang, Q., Lyons, W.B. and Prentice, M. 1997. Major features and forcing of high-latitude northern hemisphere atmospheric circulation using a 110,000-year-long glaciochemical series. Journal of Geophysical Research 102: 26,345-26,366.
Mayewski, P.A., Rohling, E.E., Stager, J.C., Karlen, W., Maasch, K.A., Meeker, L.D., Meyerson, E.A., Gasse, F., van Kreveld, S., Holmgren, K., Lee-Thorp, J., Rosqvist, G. Rack, F., Staubwasser, M., Schneider, R.R. and Steig, E.J. 2004. Holocene climate variability. Quaternary Research 62: 243-255.
O'Brien, S.R., Mayewski, P.A., Meeker, L.D., Meese, D.A., Twickler, M.S. and Whitlow, S.E. 1995. Complexity of Holocene climate as reconstructed from a Greenland ice core. Science 270: 1962-1964.
Last updated 14 June 2006
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Scientists study annual growth rings in trees to determine ancient patterns of temperature and precipitation.

WASHINGTON (AP) ­ An unusually warm period a millennium ago may have been part of a natural planetary cycle, say researchers who studied tree rings.

The study, appearing in the March 21 2002 issue of the journal Science, analyzed ancient tree rings from 14 sites on three continents in the northern hemisphere and concluded that temperatures in an era known as the Medieval Warm Period some 800 to 1,000 years ago closely matched the warming trend of the 20th century.

In recent years, many climate scientists have said an unprecedented warming spell that began last century and continues is caused by an enhanced greenhouse effect. While the natural greenhouse effect keeps the Earth at a livable temperature, the enhanced greenhouse effect is blamed on an increase in the atmosphere of gases, principally carbon dioxide, from the burning of fossil fuels.

The tree-ring study gives another perspective on Earth's natural cycles, said Edward Cook of the Lamont-Doherty Earth Observatory in Palisades, N.Y. Cook is co-author of the study with Jan Esper and Fritz Schweingruber of the Swiss Federal Research Institute.

Cook said the study shows the Earth to be "capable of rapid changes and long periods of above average warmth on its own without enhanced greenhouse warming caused by human activities.

"We don't use this as a refutation of greenhouse warming," said Cook. "But it does show that there are processes within the Earth's natural climate system that produce large changes that might be viewed as comparable to what we have seen in the 20th century."

Cook said the study found that, based on the growth of rings in the trunks of trees that lived hundreds of years ago, the temperatures during the Medieval Warm Period were about equal to the warming trend that started in the 20th century.

Cook said data used in the IPCC panel's calculation is based on a model that compared the pre-industrial age climate with the climate of the 20th century. The model did not include a Medieval Warm Period. Including data from that era could change the calculations, Cook said.

"The Medieval Warm Period is in some sense comparable up to 1990 in the 20th century," said Cook. "But that does not say that the 20th century hasn't been perturbed by greenhouse gases. The real challenge is to factor out the natural variability from" manmade causes of global warming.

Keith Briffa and Timothy Osborn, climate scientists at the University of East Anglia in Britain, said the study by Cook and his colleagues "provides evidence for greater climate swings in the last 1,000 years than has yet been generally accepted." In a commentary in Science, Briffa and Osborn said a need exists for more such independent studies to refine predictions for global warming in this century.
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Global Warming - Some Inconvenient Glaciers
BY: DENNIS T. AVERY, JUNE 8, 2006

CHURCHVILLE, VA-Al Gore says the world's glaciers are melting because humanity has emitted too much CO2. However, a new peer-reviewed study shows that in South America's Andes Mountains the glaciers' advances and retreats have not been governed by CO2, but by small variations in the sun's intensity.

The study, led by P.J. Polissar of the University of Massachusetts, found that Andean glaciers expanded only four times during the 600 years of the Little Ice Age, which lasted from 1250 AD to 1850. Each of those glacier advances occurred during a solar minimum, when the sun's lowered activity apparently dropped the mountain-top temperatures by 2-4 degrees C and increased precipitation by about 20 percent.

The Polissar team's report, "Solar Modulation of Little Ice Age Climate in the Tropical Andes," was recently published online in the Proceedings of the National Academy of Sciences.

The team studied the glaciers' moraines-piles of rocks, soil, tree trunks and other glacial debris left behind when the glaciers retreated. Then they matched the glacial debris with the sediment layers in nearby mountain lakes. The pronounced seasonality in the Andes precipitation allows the researchers to count years in the sediments and precisely date the glacial advances.

The Andes glacier study not only links glacial advances and retreats with the sun, but emphasizes that the earth's glaciers have often retreated-and even disappeared-during past centuries, long before humans built cars and smokestacks. Most of the Andes glaciers must have disappeared during the Holocene Warming that ended just 5,000 years ago. Temperatures then were as much as 2 degrees C warmer than today's. So far, the Modern Warming has produced about only 0.8 degrees C of total temperature rise in its 150 years.

The sun has been linked to earth's climate changes for the past 400 years-by sunspot records. Early astronomers noted that the two coldest periods of the Little Ice Age occurred when there were virtually no sunspots on the sun. The Sporer Minimum lasted from 1420 to 1570, and the Maunder Minimum from 1645 to 1710.

The solar-earth linkage came to the fore again in the 1980s, when researchers brought up the first long ice cores from Greenland and the Antarctic. The 400,000 years of temperature history contained in the ice cores clearly showed a moderate, natural cycle that raised temperatures at the latitude of New York and Paris by about 2 degrees C, and then lowered them by a similar amount. The cycles averaged about 1500 years in length. Cosmic-ray-produced Carbon 14 and beryllium 10 isotopes in the ice clearly linked this temperature cycle to the sun.

The question for Al Gore is not whether our temperatures are rising; the key question is why they're rising. Antarctic ice cores tell us that temperatures and CO2 in the atmosphere have tracked closely together through recent Ice Ages, but the CO2 changes have lagged behind the temperature changes by about 800 years. Higher temperatures have produced more atmospheric CO2, rather than CO2 producing higher temperatures! That's because most of the planet's CO2 is stored in the oceans, and as the seawater warms, it can't hold as much CO2.

If CO2 is the driving climate force, why did the earth begin warming in 1850, while human CO2 emissions didn't start to really expand until about 1940? Mr. Gore doesn't tell us the answer.

Why did the earth's temperatures decline from 1940 to 1975, even as CO2 emissions were soaring? Mr. Gore doesn't say.

How warm will New York get in the Modern Warming? Apparently Mr. Gore can't tell us, but a total of 2 degrees C seems likely-based on the history in the ice cores.
--------------------------------------------------------------------

DENNIS T. AVERY is a senior fellow for Hudson Institute in Washington, D.C. ========================================
A note on glaciers as temperature indicators (Clyde Spencer)

With respect to glaciers being the equivalent of a Mine Canary, they are a poor indicator of temperature. Let's assume for a moment that an alpine glacier were at least 300' above a line that never went above freezing. An increase of 1 deg F should have no impact on the ice in that region. That's assuming an adiabatic lapse rate of about 3.5 deg/1,000'. Carrying that a little further, if a glacier's zone of wastage was static before the recent temperature increases, then I would expect, all other things being equal, that the zone of wastage would only retreat about 300' in elevation.

The trick here is that all other things are probably not equal. Regardless of the average temperature in the zone of wastage, if the amount of snow falling in the zone of accumulation increases, the snout will start to move forward (after a time delay.) So what will cause a glacier to 'retreat?' Decrease in precipitation in the zone of accumulation. Increase in melting or sublimation along the course of the glacier. That could be the result of increased windiness, increased atmospheric temperature, a decrease in cloudiness, or more absorption of sunlight because of dust or soot falling on the ice. It could also result from an increase in the output from the sun.

The relative effects of the above are not well known and have not been monitored in any rigorous way for the last 100 years. I have heard, but not personally confirmed, that the south-facing glaciers in Glacier National Park are retreating rapidly, but the north-facing ones are static. If that is true, it would seem to argue against a change in average temperature, and suggest a decrease in cloudiness and/or increase in solar insolation.
***********************

B. Problems with Hockeystick analysis

Misled again: The Hockey Stick climate
History is flawed, and so is the process by which its author's claims have been adjudicated

Steve McIntyre and Ross McKitrick
Financial Post (Toronto,) July 12, 2006

Many people have heard the claim that the 1990s were the warmest decade of the millennium and that 1998 was the warmest year. Environment Canada headlined them on pamphlets mailed across the country a few years ago. These claims interested us in verifying exactly how scientists were able to assert so confidently that the late 20th century was warmer than when the Vikings were farming Greenland (the Medieval Warm Period). Last year, the National Post profiled our published research, which had identified major flaws in what was called the Hockeystick -- a graph prominently featured in a report from the Intergovernmental Panel on Climate Change (IPCC) in 2001.
We knew that calling this icon into question would be controversial, but we did not expect it would spark a battle between two powerful committees of the U.S. House of Representatives and lead to the formation of a blue-chip panel of the U.S. National Academy of Sciences (NAS).
Shortly after last year's Post profile, The Wall Street Journal did a long article interviewing both us and the principal Hockeystick author, Michael Mann. In that article, Mann was quoted as saying he would not be "intimidated" into disclosing the algorithm by which he obtained his results.
This attracted the interest of the U.S. House of Representatives' Energy and Commerce Committee. Its members read our articles and became concerned about our allegations that Mann had withheld adverse statistical results and that his results depended on bristlecone-pine ring widths, well known to be a questionable measure for temperature. In June, 2005, they sent questions to Mann and his co-authors about verification statistics and bristlecone pines, asked Mann for the algorithm he used, and asked pro forma questions about federal funds used for their research.
This prompted a storm of controversy, ironically centering on allegations of "intimidation." Various learned societies, none of which had been offended by Mann's public refusal to provide full disclosure, were outraged that a House committee, representing the taxpayers who had paid for the results, should be trying to find out how he got them.
Then a turf war broke out. The House Science Committee felt that its jurisdiction had been impinged upon and asked the Energy and Commerce Committee to butt out. After a few months of fencing in late 2005, the Science Committee asked the US Natiojal Academy of Sciences to evaluate criticisms of Mann's work, and to assess the larger issue of historical climate data reconstructions.
The NAS agreed to the Committee's request, but only under terms that precluded a direct investigation of the issues that prompted the original dispute -- whether Mann et al. had withheld adverse results and whether the data and methodological information necessary for replication were available.
In February, 2006, the NAS appointed a panel of 12 eminent academics involved in climate science, but not directly involved in the temperature reconstructions of the past 1,000 years. They were not an entirely "independent" panel, as some were occasional co-authors with the Hockeystick authors. But even this limited independence was a major departure from procedures of the IPCC, which permits authors actively involved in scientific controversy to summarize the research -- even if they end up acting as reviewers of their own work!
In March, 2006, the NAS panel held meetings in Washington at which we made a presentation (along with Mann and seven other scientists in the field).
On July 6, the panel issued a 155-page report, which managed the delicate feat of accepting virtually all the criticisms of the Hockeystick while still saying polite things about it. A European climate scientist, who understood the balancing act, wrote us afterwards to point out it was the most severe criticism of the Hockeystick nowadays possible.
At the NAS panel, we said that Mann's "principal components" were biased toward producing hockeystick-shaped series; the NAS agreed. We said that bristlecones were not a reliable temperature proxy; the NAS agreed and said they should be "avoided." We said that Mann's reconstruction failed important verification tests; the NAS agreed. We said that more than one test statistic should be reported when assessing statistical validity; the NAS agreed. We said that current methods underestimated the inherent uncertainty; the NAS agreed. On and on. On no occasion was any claim of ours refuted.
Our original articles argued that Mann's data and methodology did not permit him to claim with confidence that 1998 was the "warmest year" of the millennium or that the 1990s were the warmest decade. The NAS panel even agreed with this. After observing that little confidence could be placed in reconstructions before 1600, they stated: 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 ..."
Based on some other studies, they conceded that Mann's reconstruction was still "plausible" but, contrary to the IPCC, they said it was impossible to put confidence intervals on this opinion.
The House Science Committee had asked the NAS panel to report on whether paleoclimate authors were withholding data and methods. The panel chairman said this topic was "too big" for them to answer. The NAS apparently plans a new panel on the generic subject of availability of scientific data.
The NAS panel drew attention to other recent studies claiming that the 20th century was warmer than the Medieval Warm Period. We've attempted to replicate these other studies as well, only to run into one obstacle after another in identifying data and methods -- similar to the problems that led to the original congressional questions about the Mann study. In one case, the authors even refused to identify the sites from which data was collected for their study!
Despite these pointless obstacles, we know enough about the "other studies" to be confident that none of them meets the methodological standards now recommended by the NAS panel. In fact, somewhat remarkably, two of the most recent studies even continue to use Mann's discredited principal components series.
In its press release, the NAS headlined that the present era is the warmest in 400 years. However, long before anyone had ever heard of the IPCC or the Hockeystick, this was the prevailing view of scientists, who coined the term Little Ice Age to refer to the period leading up to Modern Warming. It isn't news to say the average temperature is higher now compared to the past 400 years. It was news in 2001 when the IPCC claimed with confidence that the 1990s were the warmest in 1,000 years. The real news from the NAS is that it disagreed and withdrew any claim to confidence prior to 1600.
At the NAS press conference, the panel was asked about "overselling" of the warmest-in-a-millennium claim and whether any lessons could be learned. Panel chairman Gerald North noted that the Mann paper was very recent when this claim was made and observed that it was "very dangerous to pull one paper out of the literature fresh before it's had time to season." However, the panel did not comment on IPCC procedures that invited this problem.
The IPCC lead author who selected Mann's reconstruction for prominent display in the review of millennial temperature history was none other than Mann himself. At the time, he was a fresh and ambitious PhD, an odd choice to write the "consensus" review of climate history.
The system that allows such conflicts of interest has been severely criticized by some senior climate scientists, including Hans von Storch of Germany. However, the flawed process remains unchanged for the next IPCC assessment report, due in January, 2007. As reviewers of that report, we have expressed concerns to the IPCC about prominent use of graphics and empirical results from the lead authors' own freshly published papers, which have not been in print long enough to have undergone adequate, independent review and assessment and, in some cases, not even long enough to meet IPCC publication deadlines.
In our opinion, most of the press coverage to date missed one of the biggest stories.
When asked at the press conference about lessons that could be learned, panelist Kurt Cuffey said the prominent use of the Hockeystick graphic by the IPCC sent "a very misleading message." He said the over-selling did not come from the "science community," but from the "interaction of part of the science community with the broader public discourse and, in particular, with the way the [Mann et al.] reconstruction was used by the IPCC in the 2001 report."
But haven't we been told that the IPCC is the "science community?" If a knowledgeable observer such as Cuffey distinguishes the two, blaming the IPCC while defending the "science community," shouldn't we be trying to figure out exactly how the IPCC process ended up sending out a "very misleading message?" And if the process has not been fixed -- and there is no evidence that it has -- how do we know that the IPCC won't send another equally "misleading" message in the upcoming Fourth Assessment report?
-------------------------------------
Steve McIntyre is a retired mineral exploration businessman who operates http://www.climateaudit.org./
Ross McKitrick is an associate professor of economics at the University of Guelph.
===========================================

See the Truth on climate history
Terence Corcoran,
Financial Post, July 12, 2006

It says it right here on the Official Climate Change Web site of the Government of Canada: "The 20th century has been the warmest globally in the past 1,000 years." This statement is wrong on several counts, and the Government of Canada knows it. After all, the knowledge that it is wrong is the product of two Canadians who have become internationally renowned in climate circles for having debunked the idea that the world is warmer than it has been in a millennium.

The two Canadians are Steve McIntyre and Ross McKitrick. The saga of their attack on one of the great iconic myths of global warming theory has been chronicled in media all over the world, from The Wall Street Journal to The New York Times and the BBC. Top science publications such as Nature and Science have taken on the issue. It is the subject of Congressional inquiry and, most recently, review by the U.S. National Academy of Sciences.

For the latest on their work, which continues to reverberate through the global science community, see their article on this page. The National Academy of Sciences essentially upheld the McIntyre/McKitrick critique of the 1,000-year temperature change claim, widely known as the Hockeystick graph, and downgraded it to a 400-year statement. One of the NAS panelists said the United Nations Intergovernmental Panel on Climate Change had sent a "very misleading message" when it adopted the Hockey Stick as the great global symbol of man-made global warming.

Despite its now dubious authenticity, the Hockeystick continues to appear in Government of Canada publications and Web sites. It was there yesterday, a great anchor in the piles of misleading propaganda produced by Ottawa to shape opinion on climate change.

Outside of the National Post, which first carried the McIntyre/McKitrick critique of the Hockey Stick, the story has been largely ignored by Canadian media. The Globe and Mail has yet to carry one story on the subject. Only a handful of scattered references have appeared in other newspapers across the country, notably the Calgary Herald. The Toronto Star's only acknowledgement was a column by Jay Ingram, who essentially said the debate among scientists was undermining public confidence in science.

At the CBC, Quirks and Quarks, the corporation's flagship radio science show, has steadfastly ignored one of the biggest Canadian-origin science stories around. Two Canadian scientists rock the world climate community, trigger international reaction, Congressional investigation and a National Academy of Sciences report that supports the Canadians' critique of official United Nations science. No news there, apparently.

Fortunately, the CBC does not run Canada. Unfortunately, the Government of Canada does, and its handling of the 1,000-year climate claim and the Hockeystick remains a model of disingenuous fabrication. It is, in short, a Big Lie.

When the government says, "The 20th century has been the warmest globally in the past 1,000 years," it reports an untruth. Even the United Nations IPCC didn't go that far. It said there isn't 1,000 years of data for the southern hemisphere, so there's no way of knowing the 1,000-year history of global temperatures.

What the IPCC did say is that it is "very likely" the 1990s was the warmest since 1861. It also said it was "likely" (as opposed to "very" likely) that "the increase in surface temperature over the 20th century for the northern hemisphere" was greater than any century in the past 1,000 years.

That looked to be the case before McIntyre and McKitrick came along. Now, according to the National Academy of Science panel, after a review, there exists a "high level of confidence" that temperatures of the recent past are higher than at any level over the past 400 years. As for 1,000 years, the NAS panel said there's too much uncertainty to have much confidence in a conclusion.

So the Government of Canada claim was never true to the IPCC science, such as it was, and now it is even less true. In fact, it is dead wrong. A science reassessment and correction is in order. That task should fall to the Science Assessment and Integration Branch under the Atmospheric and Climate Science Directorate at the Meteorological Service of Canada. The branch took a look at McIntyre and McKitrick back in February, 2005, and glossed over the problems by saying the paper was a "reminder that science proceeds with hesitant steps." The story behind the Hockeystick has advanced beyond such bromides about scientific progress.

See the Truth. That's one of the marketing promotions for Al Gore's science fiction movie, An Inconvenient Truth. The movie promotes global-warming theory, using the bogus Hockeystick graph as part of its claim to scientific authenticity. But it's hard to 'See the Truth' when you're using a Big Lie to get your message across. One expects such crafty manipulation from Al Gore, but we should not expect it from the Government of Canada.
© National Post 2006
=======================

Breaking the "Hockeystick"
Editorial, Washington Times, June 27, 2006

It's been a busy week for climate buffs and spin-meisters, as the National Academy of Sciences released its eagerly awaited report on past climate change. Its origin is the scientific debate about the iconic "Hockeystick," the graph published by Michael Mann and colleagues that showed a smooth decline in temperature since 1000 AD -- with a sudden warming in the 20th century, presumably caused by burning of fossil fuels to generate the energy needed by our advanced civilization. Since thermometers were not available, the earlier data came from "proxies": tree rings, ice cores, lake sediments, etc.

Global Warming partisans, including some scientists and the IPCC, the UN science panel, embraced the Hockeystick as "evidence" for greenhouse warming. This, even though the Hockeystick denied the existence of natural climate fluctuations: the well-established MWP (Medieval Warm Period around 1000AD), when Vikings grew crops in Greenland, and the LIA (Little Ice Age, from about 1400 to 1850 AD), when summer harvests failed and rivers and lakes froze over during severe winters.

Two Canadian researchers led the fight against the Hockeystick, attacking both the data and statistical methodology. The battle soon spilled over into politics, with Rep. Joe Barton (R-TX) demanding that Mann reveal details of his publicly funded work to permit other scientists to replicate his controversial results - a time-honored tradition in science. But Rep. Sherwood Boehlert (R-NY) objected, partly on jurisdictional grounds, and asked the National Academy of Sciences to adjudicate. Chaired by universally respected Texas A&M professor Gerald North, the NAS panel has just released its diplomatically phrased report -- with all sides now claiming victory. The only firm conclusion is that it is warmer today than 400 years ago. The NAS panel might have stressed that 1600 AD is around the middle of the Little Ice Age. As Sen. James Inhofe, an outspoken opponent of warming scares, comments, it's like comparing summer to winter to show a catastrophic temperature trend.

But now the fun begins. CNN reports in anxious tones that the Earth has got a "fever' - implying sickness. Really? Do we want a return to the severe climate of the LIA? The New York Times reports "warmest in 1000 years," but CNN and AP up this to 2000 years. In reality, the NAS report has re-established the LIA and MWP, and broken the Hockeystick - although it never says so explicitly: "None of the reconstructions indicates that temperatures were warmer during medieval times than during the past few decades." The report might have added that Northern Europe and Greenland were much warmer than today. But the statement "improving access to data on which published temperature reconstructions are based would boost confidence in the results" supports Congressman Barton, and is a polite rebuke of Mann and coauthors for withholding data.

Altogether, a good report - if you accept its straight language and reject extrapolations.
====================================

Hockeystick Hokum

Before 1999 the accepted view on climate change was that the world had undergone a warming period in the middle ages, followed by a mid-millennium cold spell and a subsequent warming period -- the current one.

That all changed when paleoclimatologist Michael Mann's research paper eliminated the Medieval warm period from the history books. With a nice, steady temperature oscillation that persists for centuries followed by a dramatic climb over the past century, Mann's work produced the "hockey stick" graph.

The trouble is that there's no reason to believe Mann, or his "hockey stick" graph of global temperature changes. Subsequent studies have shown Mann's analysis to be less than definitive:

o In 2003, Ross McKitrick and Steven McIntyre published an article in a peer-reviewed journal showing that Mann's methodology could produce hockey sticks from even random, trendless data.

o Furthermore, in a soon to be released report by the House Energy and Commerce Committee, the three researchers -- Edward J. Wegman of George Mason University, David W. Scott of Rice University and Yasmin H. Said of Johns Hopkins University -- find that Mann's methodology is biased toward producing "hockey stick" shaped graphs.

In addition to debunking the hockey stick, Wegman goes a step further in his report, attempting to answer why Mann's mistakes were not exposed by his fellow climatologists. His conclusion is that the coterie of most frequently published climatologists is so insular and close-knit that no effective independent review of the work of Mann is likely.

"There is a tightly knit group of individuals who passionately believe in their thesis. However, our perception is that this group has a self-reinforcing feedback mechanism and, moreover, the work has been sufficiently politicized that they can hardly reassess their public positions without losing credibility."

Source: Editorial, "Hockey Stick Hokum," Wall Street Journal, July 14, 2006

Courtesy: NCPA
=============================

HOCKEYSTICK HOKUM
The Wall Street Journal, 14 July 2006
http://online.wsj.com/article/SB115283824428306460.html

It is routine these days to read in newspapers or hear -- almost anywhere the subject of climate change comes up -- that the 1990s were the "warmest decade in a millennium" and that 1998 was the warmest year in the last 1,000.

This assertion has become so accepted that it is often recited without qualification, and even without giving a source for the "fact." But a report soon to be released by the House Energy and Commerce Committee by three independent statisticians underlines yet again just how shaky this "consensus" view is, and how recent its vintage.

The claim originates from a 1999 paper by paleoclimatologist Michael Mann. Prior to Mr. Mann's work, the accepted view, as embodied in the U.N.'s 1990 report from the Intergovernmental Panel on Climate Change (IPCC), was that the world had undergone a warming period in the Middle Ages, followed by a mid-millennium cold spell and a subsequent warming period -- the current one. That consensus, as shown in the first of the two IPCC-provided graphs nearby, held that the Medieval warm period was considerably warmer than the present day.

Mr. Mann's 1999 paper eliminated the Medieval warm period from the history books, with the result being the bottom graph you see here. It's a man-made global-warming evangelist's dream, with a nice, steady temperature oscillation that persists for centuries followed by a dramatic climb over the past century. In 2001, the IPCC replaced the first graph with the second in its third report on climate change, and since then it has cropped up all over the place. Al Gore uses it in his movie.

The trouble is that there's no reason to believe that Mr. Mann, or his "hockey stick" graph of global temperature changes, is right. Questions were raised about Mr. Mann's paper almost as soon as it was published. In 2003, two Canadians, Ross McKitrick and Steven McIntyre, published an article in a peer-reviewed journal showing that Mr. Mann's methodology could produce hockey sticks from even random, trendless data.

The report commissioned by the House Energy Committee, due to be released today, backs up and reinforces that conclusion. The three researchers -- Edward J. Wegman of George Mason University, David W. Scott of Rice University and Yasmin H. Said of Johns Hopkins University -- are not climatologists; they're statisticians. Their task was to look at Mr. Mann's methods from a statistical perspective and assess their validity. Their conclusion is that Mr. Mann's papers are plagued by basic statistical errors that call his conclusions into doubt. Further, Professor Wegman's report upholds the finding of Messrs. McIntyre and McKitrick that Mr. Mann's methodology is biased toward producing "hockey stick" shaped graphs.

Mr. Wegman and his co-authors are careful to point out that doubts about temperatures in the early part of the millennium do not call into question more-recent temperature increases. But as you can see looking at these two charts, it's all about context. In the first, the present falls easily within a range of natural historical variation. The bottom chart looks alarming and discontinuous with the past, which is why global-warming alarmists have adopted it so eagerly.

In addition to debunking the hockey stick, Mr. Wegman goes a step further in his report, attempting to answer why Mr. Mann's mistakes were not exposed by his fellow climatologists. Instead, it fell to two outsiders, Messrs. McIntyre and McKitrick, to uncover the errors.

Mr. Wegman brings to bear a technique called social-network analysis to examine the community of climate researchers. His conclusion is that the coterie of most frequently published climatologists is so insular and close-knit that no effective independent review of the work of Mr. Mann is likely. "As analyzed in our social network," Mr. Wegman writes, "there is a tightly knit group of individuals who passionately believe in their thesis." He continues: "However, our perception is that this group has a self-reinforcing feedback mechanism and, moreover, the work has been sufficiently politicized that they can hardly reassess their public positions without losing credibility."

In other words, climate research often more closely resembles a mutual-admiration society than a competitive and open-minded search for scientific knowledge. And Mr. Wegman's social-network graphs suggest that Mr. Mann himself -- and his hockey stick -- is at the center of that network.

Mr. Wegman's report was initially requested by the House Energy Committee because some lawmakers were concerned that major decisions about our economy could be made on the basis of the dubious research embodied in the hockey stick. Some of the more partisan scientists and journalists howled that this was an attempt at intimidation. But as Mr. Wegman's paper shows, Congress was right to worry; his conclusions make "consensus" look more like group-think. And the dismissive reaction of the climate-research establishment to the McIntyre-McKitrick critique of the hockey stick confirms that impression.
======================================

The Wegman report (91 pages 1.2 Mb) is available at
http://energycommerce.house.gov/
or at
Climate Change Assessment 07142006_Wegman_Report.pdf