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Science/Tech See other Science/Tech Articles Title: Statistics needed The Deniers -- Part I Lawrence Solomon, National Post Published: Friday, February 02, 2007 Tuesday, November 28, 2006 In the global warming debate, there are essentially two broad camps. One believes that the science is settled, that global warming is serious and man-made, and that urgent action must be taken to mitigate or prevent a future calamity. The other believes that the science is far from settled, that precious little is known about global warming or its likely effects, and that prudence dictates more research and caution before intervening massively in the economy. The "science is settled" camp, much the larger of the two, includes many eminent scientists with impressive credentials. But just who are the global warming skeptics who question the studies from the great majority of climate scientists and what are their motives? The series Statistics needed -- The Deniers Part I Warming is real -- and has benefits -- The Deniers Part II The hurricane expert who stood up to UN junk science -- The Deniers Part III Polar scientists on thin ice -- The Deniers Part IV The original denier: into the cold -- The Deniers Part V The sun moves climate change -- The Deniers Part VI Will the sun cool us? -- The Deniers Part VII The limits of predictability -- The Deniers Part VIII Look to Mars for the truth on global warming -- The Deniers Part IX Limited role for C02 -- the Deniers Part X Many in the "science is settled" camp claim that the skeptics are untrustworthy -- that they are either cranks or otherwise at the periphery of their profession, or that they are in the pockets of Exxon or other corporate interests. The skeptics are increasingly being called Deniers, a term used by analogy to the Holocaust, to convey the catastrophe that could befall mankind if action is not taken. Increasingly, too, the press is taking up the Denier theme, convincing the public that the global-warming debate is over. In this, the first of a series, I examine The Deniers, starting with Edward Wegman. Dr. Wegman is a professor at the Center for Computational Statistics at George Mason University, chair of the National Academy of Sciences' Committee on Applied and Theoretical Statistics, and board member of the American Statistical Association. Few statisticians in the world have CVs to rival his (excerpts appear nearby). Wegman became involved in the global-warming debate after the energy and commerce committee of the U.S. House of Representatives asked him to assess one of the hottest debates in the global-warming controversy: the statistical validity of work by Michael Mann. You may not have heard of Mann or read Mann's study but you have often heard its famous conclusion: that the temperature increases that we have been experiencing are "likely to have been the largest of any century during the past 1,000 years" and that the "1990s was the warmest decade and 1998 the warmest year" of the millennium. You may have also heard of Mann's hockey-stick shaped graph, which showed relatively stable temperatures over most of the last millennium (the hockey stick's long handle), followed by a sharp increase (the hockey stick's blade) this century. Mann's findings were arguably the single most influential study in swaying the public debate, and in 2001 they became the official view of the International Panel for Climate Change, the UN body that is organizing the worldwide effort to combat global warming. But Mann's work also had its critics, particularly two Canadians, Steve McIntyre and Ross McKitrick, who published peer-reviewed critiques of their own. Wegman accepted the energy and commerce committee's assignment, and agreed to assess the Mann controversy pro bono. He conducted his third-party review by assembling an expert panel of statisticians, who also agreed to work pro bono. Wegman also consulted outside statisticians, including the Board of the American Statistical Association. At its conclusion, the Wegman review entirely vindicated the Canadian critics and repudiated Mann's work. "Our committee believes that the assessments that the decade of the 1990s was the hottest decade in a millennium and that 1998 was the hottest year in a millennium cannot be supported," Wegman stated, adding that "The paucity of data in the more remote past makes the hottest-in-a-millennium claims essentially unverifiable." When Wegman corrected Mann's statistical mistakes, the hockey stick disappeared. Wegman found that Mann made a basic error that "may be easily overlooked by someone not trained in statistical methodology. We note that there is no evidence that Dr. Mann or any of the other authors in paleoclimate studies have had significant interactions with mainstream statisticians." Instead, this small group of climate scientists were working on their own, largely in isolation, and without the academic scrutiny needed to ferret out false assumptions. Worse, the problem also applied more generally, to the broader climate-change and meteorological community, which also relied on statistical techniques in their studies. "[I]f statistical methods are being used, then statisticians ought to be funded partners engaged in the research to insure as best we possibly can that the best quality science is being done," Wegman recommended, noting that "there are a host of fundamental statistical questions that beg answers in understanding climate dynamics." In other words, Wegman believes that much of the climate science that has been done should be taken with a grain of salt -- although the studies may have been peer reviewed, the reviewers were often unqualified in statistics. Past studies, he believes, should be reassessed by competent statisticians and in future, the climate science world should do better at incorporating statistical know-how. One place to start is with the American Meteorological Society, which has a committee on probability and statistics. "I believe it is amazing for a committee whose focus is on statistics and probability that of the nine members only two are also members of the American Statistical Association, the premier statistical association in the United States, and one of those is a recent PhD with an assistant-professor appointment in a medical school." As an example of the statistical barrenness of the climate-change world, Wegman cited the American Meteorological Association's 2006 Conference on Probability and Statistics in the Atmospheric Sciences, where only eight presenters out of 62 were members of the American Statistical Association. While Wegman's advice -- to use trained statisticians in studies reliant on statistics -- may seem too obvious to need stating, the "science is settled" camp resists it. Mann's hockey-stick graph may be wrong, many experts now acknowledge, but they assert that he nevertheless came to the right conclusion. To which Wegman, and doubtless others who want more rigourous science, shake their heads in disbelief. As Wegman summed it up to the energy and commerce committee in later testimony: "I am baffled by the claim that the incorrect method doesn't matter because the answer is correct anyway. Method Wrong + Answer Correct = Bad Science." With bad science, only true believers can assert that they nevertheless obtained the right answer. LawrenceSolomon@nextcity.com. - Lawrence Solomon is executive director of Urban Renaissance Institute, a division of Energy Probe Research Foundation. THE CV OF A DENIER Edward Wegman received his Ph.D. degree in mathematical statistics from the University of Iowa. In 1978, he went to the Office of Naval Research, where he headed the Mathematical Sciences Division with responsibility Navy-wide for basic research programs. He coined the phrase computational statistics, and developed a high-profile research area around this concept, which focused on techniques and methodologies that could not be achieved without the capabilities of modern computing resources and led to a revolution in contemporary statistical graphics. Dr. Wegman was the original program director of the basic research program in Ultra High Speed Computing at the Strategic Defense Initiative's Innovative Science and Technology Office. He has served as editor or associate editor of numerous prestigious journals and has published more than 160 papers and eight books. Warming is real - and has benefits The Deniers -- Part II Lawrence Solomon, Financial Post Published: Friday, February 02, 2007 One month ago, the world heard that global warming could lead to a global catastrophe "on a scale similar to those associated with the great wars and the economic depression of the first half of the 20th century." This assessment, from Sir Nicholas Stern, former chief economist of the World Bank, made banner headlines and led prominent leaders such as British Prime Minister Tony Blair to urge immediate action to stem global warming. It also led some prominent environmentalists to denounce Sir Nicholas for what they deemed an outrageous study bereft of credibility. None of the environmentalists issued a stronger denunciation, or has better environmental credentials, than Richard S.J. Tol. Tol is a Denier, to use the terminology of the "science-is-settled" camp in the increasingly polarized global warming debate. Like many other Deniers, Tol doesn't think the evidence is in on global warming and its effects, he doesn't think there's reason to rush to action, and he doesn't think that crash programs to curb global warming are called for. Also like many other Deniers, he doesn't fit the stereotype that those who use the epithet imagine. Anything but. Tol is no fringe outsider to the scientific debate. He is at the centre of the academic investigation of global warming, a central figure in the scientific establishment that has been developing the models and the knowledge to understand the global warming phenomenon. At the United Nation's Intergovernmental Panel on Climate Change, considered by most the authoritative body in the field, Tol is involved as an author in all three of its Working Groups. He is also an author and editor of the United Nations Handbook on Methods for Climate Change Impact Assessment and Adaptation Strategies. He is also a mover and shaker in the prestigious European Climate Forum. He takes global warming seriously and has dedicated his professional life to making a contribution for the better in climate policy and related fields. Because of his immense reputation, the Stern report itself relied on Tol's work in coming to its conclusions. But Sir Nicholas twisted Tol's work out of shape to arrive at unsupportable conclusions. As one example, Sir Nicholas plucked a figure ($29 per ton of carbon dioxide) from a range that Tol prepared describing the possible costs of CO2 emissions, without divulging that in the very same study Tol concluded that the actual costs "are likely to be substantially smaller" than $14 per ton of CO2. Likewise, in an assessment of the potential consequences of rising sea levels, Sir Nicholas quoted a study co-authored by Tol that referred to the "millions at risk," ignoring that the same study then suggested greatly reduced consequences for those millions due to the ability of humans to adapt to change. Throughout his report, in fact, Sir Nicholas not only assumed worst possible cases, he also assumed that humans are passive creatures, devoid of ingenuity, who would be helpless victims to changes in the world around them. Such assumptions underpinned Sir Nicholas's claim that "the overall costs and risks of climate change will be equivalent to losing at least 5% of global GDP each year, now and forever," and led Tol to view Sir Nicholas's conclusions as "preposterous." Tol's conclusion: "The Stern review can therefore be dismissed as alarmist and incompetent." Tol and Sir Nicholas are worlds apart, and not just because of Sir Nicholas's recklessness with the facts. Where Sir Nicholas paints an altogether bleak picture, Tol's is far more nuanced: Global warming creates benefits as well as harms, he explains, and in the short term, the benefits are especially pronounced. More important, Tol is a student of human innovation and adaptation. As a native of the Netherlands, he is intimately familiar with dikes and other low-cost adaptive technologies, and the ability of humans in meeting challenges in their environment. To assume that humans in the future would not use their ingenuity and resourcefulness in sensible ways defies the history of mankind and ultimately serves no one. Yes, global warming is real, he believes, and yes, measures to mitigate it should be taken. But unlike the advocates who believe that the science is settled, and the global warning debate is over, Tol thinks that much research needs to be done before we know how best to respond. "There is no risk of damage [from global warming] that would force us to act injudiciously," he explains. "We've got enough time to look for the economically most effective options, rather than dash into 'actionism,' which then becomes very expensive." THE CV OF A DENIER: Richard Tol received his PhD in Economics from the Vrije Universiteit in Amsterdam. He is Michael Otto Professor of Sustainability and Global Change at Hamburg University, director of the Centre for Marine and Atmospheric Science, principal researcher at the Institute for Environmental Studies at Vrije Universiteit, and Adjunct Professor at the Center for Integrated Study of the Human Dimensions of Global Change, at Carnegie Mellon University. He is a board member of the Centre for Marine and Climate Research, the International Max Planck Research Schools of Earth Systems Modelling and Maritime Affairs, and the European Forum on Integrated Environmental Assessment. He is an editor of Energy Economics, an associate editor of Environmental and Resource Economics, and a member of the editorial board of Environmental Science and Policy and Integrated Assessment.
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#1. To: richard9151 (#0)
I don't know about global warming, but WE HAVEN'T HAD TWO DAYS IN A ROW WITHOUT RAIN here in Okielahoma this year. Suppose to rain for at least the next two weeks. Noah, oh Noah!
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