Regular visitors will know that the waka waka waka editorial board has long regarded global-warming alarmism with a wary eye. (See our collection of related posts here.) There are so many who stand to benefit from warmist scare-mongering — academics enjoying lavish financial support and the eager attention of media and political institutions around the world; “green-energy” lobbyists, investors, and entrepreneurs; politicians and bureaucrats who occupy well-padded sinecures that exist only as a result of this “crisis”; anticapitalists, globalists, and other activists of the Left who see it as a vehicle with which to carry forward their ideological vision — that wisdom demands a measure of caution regarding their claims and petitions, especially when we keep in mind that the remedies they propose involve enormous costs (and for some, notably many of those pressing the agenda, enormous profits), and a radical transformation of the existing world order.
Recently a group of scientists published an open letter in the Wall Street Journal arguing that the pace of warming has been exaggerated, that the effect of CO2 on global temperature has been inflated as well, that there are in fact beneficial effects to both higher levels of atmospheric CO2 and a warmer climate, that the Earth’s climate has warmed and cooled continually over the eons since long before human activity could possibly have had anything to do with it, and that the radical remedies on offer are simply not justified by any positive knowledge.
Another group of scientists replied with an open letter of their own, and the original group has now responded. Taken together these provide a good summary of the state of the debate, and so I will reproduce them in full, below the fold.
Editor’s Note: The following has been signed by the 16 scientists listed at the end of the article:
A candidate for public office in any contemporary democracy may have to consider what, if anything, to do about “global warming.” Candidates should understand that the oft-repeated claim that nearly all scientists demand that something dramatic be done to stop global warming is not true. In fact, a large and growing number of distinguished scientists and engineers do not agree that drastic actions on global warming are needed.
In September, Nobel Prize-winning physicist Ivar Giaever, a supporter of President Obama in the last election, publicly resigned from the American Physical Society (APS) with a letter that begins: “I did not renew [my membership] because I cannot live with the [APS policy] statement: ‘The evidence is incontrovertible: Global warming is occurring. If no mitigating actions are taken, significant disruptions in the Earth’s physical and ecological systems, social systems, security and human health are likely to occur. We must reduce emissions of greenhouse gases beginning now.’ In the APS it is OK to discuss whether the mass of the proton changes over time and how a multi-universe behaves, but the evidence of global warming is incontrovertible?”
In spite of a multidecade international campaign to enforce the message that increasing amounts of the “pollutant” carbon dioxide will destroy civilization, large numbers of scientists, many very prominent, share the opinions of Dr. Giaever. And the number of scientific “heretics” is growing with each passing year. The reason is a collection of stubborn scientific facts.
Perhaps the most inconvenient fact is the lack of global warming for well over 10 years now. This is known to the warming establishment, as one can see from the 2009 “Climategate” email of climate scientist Kevin Trenberth: “The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t.” But the warming is only missing if one believes computer models where so-called feedbacks involving water vapor and clouds greatly amplify the small effect of CO2.
The lack of warming for more than a decade—indeed, the smaller-than-predicted warming over the 22 years since the U.N.’s Intergovernmental Panel on Climate Change (IPCC) began issuing projections—suggests that computer models have greatly exaggerated how much warming additional CO2 can cause. Faced with this embarrassment, those promoting alarm have shifted their drumbeat from warming to weather extremes, to enable anything unusual that happens in our chaotic climate to be ascribed to CO2.
The fact is that CO2 is not a pollutant. CO2 is a colorless and odorless gas, exhaled at high concentrations by each of us, and a key component of the biosphere’s life cycle. Plants do so much better with more CO2 that greenhouse operators often increase the CO2 concentrations by factors of three or four to get better growth. This is no surprise since plants and animals evolved when CO2 concentrations were about 10 times larger than they are today. Better plant varieties, chemical fertilizers and agricultural management contributed to the great increase in agricultural yields of the past century, but part of the increase almost certainly came from additional CO2 in the atmosphere.
Although the number of publicly dissenting scientists is growing, many young scientists furtively say that while they also have serious doubts about the global-warming message, they are afraid to speak up for fear of not being promoted—or worse. They have good reason to worry. In 2003, Dr. Chris de Freitas, the editor of the journal Climate Research, dared to publish a peer-reviewed article with the politically incorrect (but factually correct) conclusion that the recent warming is not unusual in the context of climate changes over the past thousand years. The international warming establishment quickly mounted a determined campaign to have Dr. de Freitas removed from his editorial job and fired from his university position. Fortunately, Dr. de Freitas was able to keep his university job.
This is not the way science is supposed to work, but we have seen it before—for example, in the frightening period when Trofim Lysenko hijacked biology in the Soviet Union. Soviet biologists who revealed that they believed in genes, which Lysenko maintained were a bourgeois fiction, were fired from their jobs. Many were sent to the gulag and some were condemned to death.
Why is there so much passion about global warming, and why has the issue become so vexing that the American Physical Society, from which Dr. Giaever resigned a few months ago, refused the seemingly reasonable request by many of its members to remove the word “incontrovertible” from its description of a scientific issue? There are several reasons, but a good place to start is the old question “cui bono?” Or the modern update, “Follow the money.”
Alarmism over climate is of great benefit to many, providing government funding for academic research and a reason for government bureaucracies to grow. Alarmism also offers an excuse for governments to raise taxes, taxpayer-funded subsidies for businesses that understand how to work the political system, and a lure for big donations to charitable foundations promising to save the planet. Lysenko and his team lived very well, and they fiercely defended their dogma and the privileges it brought them.
Speaking for many scientists and engineers who have looked carefully and independently at the science of climate, we have a message to any candidate for public office: There is no compelling scientific argument for drastic action to “decarbonize” the world’s economy. Even if one accepts the inflated climate forecasts of the IPCC, aggressive greenhouse-gas control policies are not justified economically.
A recent study of a wide variety of policy options by Yale economist William Nordhaus showed that nearly the highest benefit-to-cost ratio is achieved for a policy that allows 50 more years of economic growth unimpeded by greenhouse gas controls. This would be especially beneficial to the less-developed parts of the world that would like to share some of the same advantages of material well-being, health and life expectancy that the fully developed parts of the world enjoy now. Many other policy responses would have a negative return on investment. And it is likely that more CO2 and the modest warming that may come with it will be an overall benefit to the planet.
If elected officials feel compelled to “do something” about climate, we recommend supporting the excellent scientists who are increasing our understanding of climate with well-designed instruments on satellites, in the oceans and on land, and in the analysis of observational data. The better we understand climate, the better we can cope with its ever-changing nature, which has complicated human life throughout history. However, much of the huge private and government investment in climate is badly in need of critical review.
Every candidate should support rational measures to protect and improve our environment, but it makes no sense at all to back expensive programs that divert resources from real needs and are based on alarming but untenable claims of “incontrovertible” evidence.
Claude Allegre, former director of the Institute for the Study of the Earth, University of Paris; J. Scott Armstrong, cofounder of the Journal of Forecasting and the International Journal of Forecasting; Jan Breslow, head of the Laboratory of Biochemical Genetics and Metabolism, Rockefeller University; Roger Cohen, fellow, American Physical Society; Edward David, member, National Academy of Engineering and National Academy of Sciences; William Happer, professor of physics, Princeton; Michael Kelly, professor of technology, University of Cambridge, U.K.; William Kininmonth, former head of climate research at the Australian Bureau of Meteorology; Richard Lindzen, professor of atmospheric sciences, MIT; James McGrath, professor of chemistry, Virginia Technical University; Rodney Nichols, former president and CEO of the New York Academy of Sciences; Burt Rutan, aerospace engineer, designer of Voyager and SpaceShipOne; Harrison H. Schmitt, Apollo 17 astronaut and former U.S. senator; Nir Shaviv, professor of astrophysics, Hebrew University, Jerusalem; Henk Tennekes, former director, Royal Dutch Meteorological Service; Antonio Zichichi, president of the World Federation of Scientists, Geneva.
On February 1st came this reply:
Do you consult your dentist about your heart condition? In science, as in any area, reputations are based on knowledge and expertise in a field and on published, peer-reviewed work. If you need surgery, you want a highly experienced expert in the field who has done a large number of the proposed operations.
You published “No Need to Panic About Global Warming” (op-ed, Jan. 27) on climate change by the climate-science equivalent of dentists practicing cardiology. While accomplished in their own fields, most of these authors have no expertise in climate science. The few authors who have such expertise are known to have extreme views that are out of step with nearly every other climate expert. This happens in nearly every field of science. For example, there is a retrovirus expert who does not accept that HIV causes AIDS. And it is instructive to recall that a few scientists continued to state that smoking did not cause cancer, long after that was settled science.
Climate experts know that the long-term warming trend has not abated in the past decade. In fact, it was the warmest decade on record. Observations show unequivocally that our planet is getting hotter. And computer models have recently shown that during periods when there is a smaller increase of surface temperatures, warming is occurring elsewhere in the climate system, typically in the deep ocean. Such periods are a relatively common climate phenomenon, are consistent with our physical understanding of how the climate system works, and certainly do not invalidate our understanding of human-induced warming or the models used to simulate that warming.
Thus, climate experts also know what one of us, Kevin Trenberth, actually meant by the out-of-context, misrepresented quote used in the op-ed. Mr. Trenberth was lamenting the inadequacy of observing systems to fully monitor warming trends in the deep ocean and other aspects of the short-term variations that always occur, together with the long-term human-induced warming trend.
The National Academy of Sciences of the U.S. (set up by President Abraham Lincoln to advise on scientific issues), as well as major national academies of science around the world and every other authoritative body of scientists active in climate research have stated that the science is clear: The world is heating up and humans are primarily responsible. Impacts are already apparent and will increase. Reducing future impacts will require significant reductions in emissions of heat-trapping gases.
Research shows that more than 97% of scientists actively publishing in the field agree that climate change is real and human caused. It would be an act of recklessness for any political leader to disregard the weight of evidence and ignore the enormous risks that climate change clearly poses. In addition, there is very clear evidence that investing in the transition to a low-carbon economy will not only allow the world to avoid the worst risks of climate change, but could also drive decades of economic growth. Just what the doctor ordered.
Kevin Trenberth, Sc.D.
Distinguished Senior Scientist
Climate Analysis Section National Center for Atmospheric Research
La Jolla, Calif.
Kevin Trenberth, Sc.D, Distinguished Senior Scientist, Climate Analysis Section, National Center for Atmospheric Research
Richard Somerville, Ph.D., Distinguished Professor, Scripps Institution of Oceanography, University of California, San Diego
Katharine Hayhoe, Ph.D., Director, Climate Science Center, Texas Tech University
Rasmus Benestad, Ph.D., Senior Scientist, The Norwegian Meteorological Institute
Gerald Meehl, Ph.D., Senior Scientist, Climate and Global Dynamics Division, National Center for Atmospheric Research
Michael Oppenheimer, Ph.D., Professor of Geosciences; Director, Program in Science, Technology and Environmental Policy, Princeton University
Peter Gleick, Ph.D., co-founder and president, Pacific Institute for Studies in Development, Environment, and Security
Michael C. MacCracken, Ph.D., Chief Scientist, Climate Institute, Washington
Michael Mann, Ph.D., Director, Earth System Science Center, Pennsylvania State University
Steven Running, Ph.D., Professor, Director, Numerical Terradynamic Simulation Group, University of Montana
Robert Corell, Ph.D., Chair, Arctic Climate Impact Assessment; Principal, Global Environment Technology Foundation
Dennis Ojima, Ph.D., Professor, Senior Research Scientist, and Head of the Dept. of Interior’s Climate Science Center at Colorado State University
Josh Willis, Ph.D., Climate Scientist, NASA’s Jet Propulsion Laboratory
Matthew England, Ph.D., Professor, Joint Director of the Climate Change Research Centre, University of New South Wales, Australia
Ken Caldeira, Ph.D., Atmospheric Scientist, Dept. of Global Ecology, Carnegie Institution
Warren Washington, Ph.D., Senior Scientist, National Center for Atmospheric Research
Terry L. Root, Ph.D., Senior Fellow, Woods Institute for the Environment, Stanford University
David Karoly, Ph.D., ARC Federation Fellow and Professor, University of Melbourne, Australia
Jeffrey Kiehl, Ph.D., Senior Scientist, Climate and Global Dynamics Division, National Center for Atmospheric Research
Donald Wuebbles, Ph.D., Professor of Atmospheric Sciences, University of Illinois
Camille Parmesan, Ph.D., Professor of Biology, University of Texas; Professor of Global Change Biology, Marine Institute, University of Plymouth, UK
Simon Donner, Ph.D., Assistant Professor, Department of Geography, University of British Columbia, Canada
Barrett N. Rock, Ph.D., Professor, Complex Systems Research Center and Department of Natural Resources, University of New Hampshire
David Griggs, Ph.D., Professor and Director, Monash Sustainability Institute, Monash University, Australia
Roger N. Jones, Ph.D., Professor, Professorial Research Fellow, Centre for Strategic Economic Studies, Victoria University, Australia
William L. Chameides, Ph.D., Dean and Professor, School of the Environment, Duke University
Gary Yohe, Ph.D., Professor, Economics and Environmental Studies, Wesleyan University, CT
Robert Watson, Ph.D., Chief Scientific Advisor to the UK Department of Environment, Food and Rural Affairs; Chair of Environmental Sciences, University of East Anglia
Steven Sherwood, Ph.D., Director, Climate Change Research Centre, University of New South Wales, Sydney, Australia
Chris Rapley, Ph.D., Professor of Climate Science, University College London, UK
Joan Kleypas, Ph.D., Scientist, Climate and Global Dynamics Division, National Center for Atmospheric Research
James J. McCarthy, Ph.D., Professor of Biological Oceanography, Harvard University
Stefan Rahmstorf, Ph.D., Professor of Physics of the Oceans, Potsdam University, Germany
Julia Cole, Ph.D., Professor, Geosciences and Atmospheric Sciences, University of Arizona
William H. Schlesinger, Ph.D., President, Cary Institute of Ecosystem Studies
Jonathan Overpeck, Ph.D., Professor of Geosciences and Atmospheric Sciences, University of Arizona
Eric Rignot, Ph.D., Senior Research Scientist, NASA’s Jet Propulsion Laboratory; Professor of Earth System Science, University of California, Irvine
Wolfgang Cramer, Professor of Global Ecology, Mediterranean Institute for Biodiversity and Ecology, CNRS, Aix-en-Provence, France
Today, the authors of the original post have replied to Trenberth et al.:
Editor’s Note: The authors of the following letter, listed below, are also the signatories of “No Need to Panic About Global Warming,” an op-ed that appeared in the Journal on January 27. This letter responds to criticisms of the op-ed made by Kevin Trenberth and 37 others in a letter published Feb. 1, and by Robert Byer of the American Physical Society in a letter published Feb. 6.
The interest generated by our Wall Street Journal op-ed of Jan. 27, “No Need to Panic about Global Warming,” is gratifying but so extensive that we will limit our response to the letter to the editor the Journal published on Feb. 1, 2012 by Kevin Trenberth and 37 other signatories, and to the Feb. 6 letter by Robert Byer, President of the American Physical Society. (We, of course, thank the writers of supportive letters.)
We agree with Mr. Trenberth et al. that expertise is important in medical care, as it is in any matter of importance to humans or our environment. Consider then that by eliminating fossil fuels, the recipient of medical care (all of us) is being asked to submit to what amounts to an economic heart transplant. According to most patient bills of rights, the patient has a strong say in the treatment decision. Natural questions from the patient are whether a heart transplant is really needed, and how successful the diagnostic team has been in the past.
In this respect, an important gauge of scientific expertise is the ability to make successful predictions. When predictions fail, we say the theory is “falsified” and we should look for the reasons for the failure. Shown in the nearby graph is the measured annual temperature of the earth since 1989, just before the first report of the Intergovernmental Panel on Climate Change (IPCC). Also shown are the projections of the likely increase of temperature, as published in the Summaries of each of the four IPCC reports, the first in the year 1990 and the last in the year 2007.
These projections were based on IPCC computer models of how increased atmospheric CO2 should warm the earth. Some of the models predict higher or lower rates of warming, but the projections shown in the graph and their extensions into the distant future are the basis of most studies of environmental effects and mitigation policy options. Year-to-year fluctuations and discrepancies are unimportant; longer-term trends are significant.
From the graph it appears that the projections exaggerate, substantially, the response of the earth’s temperature to CO2 which increased by about 11% from 1989 through 2011. Furthermore, when one examines the historical temperature record throughout the 20th century and into the 21st, the data strongly suggest a much lower CO2 effect than almost all models calculate.
The Trenberth letter tells us that “computer models have recently shown that during periods when there is a smaller increase of surface temperatures, warming is occurring elsewhere in the climate system, typically in the deep ocean.” The ARGO system of diving buoys is providing increasingly reliable data on the temperature of the upper layers of the ocean, where much of any heat from global warming must reside. But much like the surface temperature shown in the graph, the heat content of the upper layers of the world’s oceans is not increasing nearly as fast as IPCC models predict, perhaps not increasing at all. Why should we now believe exaggerating IPCC models that tell us of “missing heat” hiding in the one place where it cannot yet be reliably measured—the deep ocean?
Given this dubious track record of prediction, it is entirely reasonable to ask for a second opinion. We have offered ours. With apologies for any immodesty, we all have enjoyed distinguished careers in climate science or in key science and engineering disciplines (such as physics, aeronautics, geology, biology, forecasting) on which climate science is based.
Trenberth et al. tell us that the managements of major national academies of science have said that “the science is clear, the world is heating up and humans are primarily responsible.” Apparently every generation of humanity needs to relearn that Mother Nature tells us what the science is, not authoritarian academy bureaucrats or computer models.
One reason to be on guard, as we explained in our original op-ed, is that motives other than objective science are at work in much of the scientific establishment. All of us are members of major academies and scientific societies, but we urge Journal readers not to depend on pompous academy pronouncements—on what we say—but to follow the motto of the Royal Society of Great Britain, one of the oldest learned societies in the world: nullius in verba—take nobody’s word for it. As we said in our op-ed, everyone should look at certain stubborn facts that don’t fit the theory espoused in the Trenberth letter, for example—the graph of surface temperature above, and similar data for the temperature of the lower atmosphere and the upper oceans.
What are we to make of the letter’s claim: “Climate experts know that the long-term warming trend has not abated in the past decade. In fact, it was the warmest decade on record.” We don’t see any warming trend after the year 2000 in the graph. It is true that the years 2000-2010 were perhaps 0.2 C warmer than the preceding 10 years. But the record indicates that long before CO2 concentrations of the atmosphere began to increase, the earth began to warm in fits and starts at the end of the Little Ice Age—hundreds of years ago. This long term-trend is quite likely to produce several warm years in a row. The question is how much of the warming comes from CO2 and how much is due to other, both natural and anthropogenic, factors?
There have been many times in the past when there were warmer decades. It may have been warmer in medieval times, when the Vikings settled Greenland, and when wine was exported from England. Many proxy indicators show that the Medieval Warming was global in extent. And there were even warmer periods a few thousand years ago during the Holocene Climate Optimum. The fact is that there are very powerful influences on the earth’s climate that have nothing to do with human-generated CO2. The graph strongly suggests that the IPCC has greatly underestimated the natural sources of warming (and cooling) and has greatly exaggerated the warming from CO2.
The Trenberth letter states: “Research shows that more than 97% of scientists actively publishing in the field agree that climate change is real and human caused.” However, the claim of 97% support is deceptive. The surveys contained trivial polling questions that even we would agree with. Thus, these surveys find that large majorities agree that temperatures have increased since 1800 and that human activities have some impact.
But what is being disputed is the size and nature of the human contribution to global warming. To claim, as the Trenberth letter apparently does, that disputing this constitutes “extreme views that are out of step with nearly every other climate expert” is peculiar indeed.
One might infer from the Trenberth letter that scientific facts are determined by majority vote. Some postmodern philosophers have made such claims. But scientific facts come from observations, experiments and careful analysis, not from the near-unanimous vote of some group of people.
The continued efforts of the climate establishment to eliminate “extreme views” can acquire a seriously threatening nature when efforts are directed at silencing scientific opposition. In our op-ed we mentioned the campaign circa 2003 to have Dr. Chris de Freitas removed not only from his position as editor of the journal Climate Research, but from his university job as well. Much of that campaign is documented in Climategate emails, where one of the signatories of the Trenberth et al. letter writes: “I believe that a boycott against publishing, reviewing for, or even citing articles from Climate Research [then edited by Dr. de Freitas] is certainly warranted, but perhaps the minimum action that should be taken.”
Or consider the resignation last year of Wolfgang Wagner, editor-in-chief of the journal Remote Sensing. In a fulsome resignation editorial eerily reminiscent of past recantations by political and religious heretics, Mr. Wagner confessed to his “sin” of publishing a properly peer-reviewed paper by University of Alabama scientists Roy Spencer and William Braswell containing the finding that IPCC models exaggerate the warming caused by increasing CO2.
The Trenberth letter tells us that decarbonization of the world’s economy would “drive decades of economic growth.” This is not a scientific statement nor is there evidence it is true. A premature global-scale transition from hydrocarbon fuels would require massive government intervention to support the deployment of more expensive energy technology. If there were economic advantages to investing in technology that depends on taxpayer support, companies like Beacon Power, Evergreen Solar, Solar Millenium, SpectraWatt, Solyndra, Ener1 and the Renewable Energy Development Corporation would be prospering instead of filing for bankruptcy in only the past few months.
The European experience with green technologies has also been discouraging. A study found that every new “green job” in Spain destroyed more than two existing jobs and diverted capital that would have created new jobs elsewhere in the economy. More recently, European governments have been cutting subsidies for expensive CO2-emissionless energy technologies, not what one would expect if such subsidies were stimulating otherwise languid economies. And as we pointed out in our op-ed, it is unlikely that there will be any environmental benefit from the reduced CO2 emissions associated with green technologies, which are based on the demonization of CO2.
Turning to the letter of the president of the American Physical Society (APS), Robert Byer, we read, “The statement [on climate] does not declare, as the signatories of the letter [our op-ed] suggest, that the human contribution to climate change is incontrovertible.” This seems to suggest that APS does not in fact consider the science on this key question to be settled.
Yet here is the critical paragraph from the statement that caused the resignation of Nobel laureate Ivar Giaever and many other long-time members of the APS: “The evidence is incontrovertible: Global warming is occurring. If no mitigating actions are taken, significant disruptions in the Earth’s physical and ecological systems, social systems, security and human health are likely to occur. We must reduce emissions of greenhouse gases beginning now.” No reasonable person can read this and avoid the conclusion that APS is declaring the human impact “incontrovertible.” Otherwise there would be no logical link from “global warming” to the shrill call for mitigation.
The APS response to the concerns of its membership was better than that of any other scientific society, but it was not democratic. The management of APS took months to review the statement quoted above, and it eventually declared that not a word needed to be changed, though some 750 words were added to try to explain what the original 157 words really meant. APS members were permitted to send in comments but the comments were never made public.
In spite of the obstinacy of some in APS management, APS members of good will are supporting the establishment of a politics-free, climate physics study group within the Society. If successful, it will facilitate much needed discussion, debate, and independent research in the physics of climate.
In summary, science progresses by testing predictions against real world data obtained from direct observations and rigorous experiments. The stakes in the global-warming debate are much too high to ignore this observational evidence and declare the science settled. Though there are many more scientists who are extremely well qualified and have reached the same conclusions we have, we stress again that science is not a democratic exercise and our conclusions must be based on observational evidence.
The computer-model predictions of alarming global warming have seriously exaggerated the warming by CO2 and have underestimated other causes. Since CO2 is not a pollutant but a substantial benefit to agriculture, and since its warming potential has been greatly exaggerated, it is time for the world to rethink its frenzied pursuit of decarbonization at any cost.
Claude Allegre, former director of the Institute for the Study of the Earth, University of Paris; J. Scott Armstrong, cofounder of the Journal of Forecasting and the International Journal of Forecasting; Jan Breslow, head of the Laboratory of Biochemical Genetics and Metabolism, Rockefeller University; Roger Cohen, fellow, American Physical Society; Edward David, member, National Academy of Engineering and National Academy of Sciences; William Happer, professor of physics, Princeton; Michael Kelly, professor of technology, University of Cambridge, U.K.; William Kininmonth, former head of climate research at the Australian Bureau of Meteorology; Richard Lindzen, professor of atmospheric sciences, MIT; James McGrath, professor of chemistry, Virginia Technical University; Rodney Nichols, former president and CEO of the New York Academy of Sciences; Burt Rutan, aerospace engineer, designer of Voyager and SpaceShipOne; Harrison H. Schmitt, Apollo 17 astronaut and former U.S. senator; Nir Shaviv, professor of astrophysics, Hebrew University, Jerusalem; Henk Tennekes, former director, Royal Dutch Meteorological Service; Antoninio Zichichi, president of the World Federation of Scientists, Geneva.
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