Abstract
The latest calculations on the effects of regional nuclear conflict (“Regional Forecasts,” May/June 2007 Bulletin) are reminiscent of an important shock of the 1980s: the concept of “nuclear winter.” At the time it was thought that a few hundred nuclear detonations in the megaton range on highly combustible targets such as cities and oil refineries could cause prolonged global cooling and loss of sunlight, and catastrophic impacts upon food supplies.
Thanks to these new simulations, we now know that even a detonation of around 100 “small” nuclear weapons of the size used on Hiroshima (12- to 15-kiloton range) could trigger a cooling effect larger than that witnessed during the pre-industrial Little Ice Age.
This is a shocking reminder of the devastating potential of even relatively low-yield nuclear weapons. But it is significant that the new research does not address the potential impact of larger weapons belonging to major nuclear powers such as Britain, France, Russia, China, or the United States. Perhaps the researchers wanted to distance themselves from implied criticism of U.S. nuclear strategy and policy?
Using their figures and applying well-known scaling laws, it is possible to make some first-order approximations of the destructive potential of some of the bigger nuclear weapons out there. Consider one Trident nuclear missile submarine: The British variant has 16 missiles with 48 independently targetable 100-kiloton warheads. One 100-kiloton warhead is approximately eight times the size of the Hiroshima bomb and would cause blast and fire effects over four times the area. Crudely, then, the area impacted by 48 100-kiloton warheads would be equivalent to 192 Hi-roshimas. This is already nearly twice the impact of the scenario used in these latest nuclear winter simulations, and in fact, is likely to be an underestimation because a key effect, widespread fires, are particularly significant for larger-scale nuclear detonations.
The aforementioned estimates utilize blast and fire casualty predictions developed by the now-defunct U.S. Office of Technology Assessment (OTA). The fire spread model developed by Theodore Postol at MIT predicts that fires are likely to rage over areas some three and a half to four times larger than OTA estimates. Taking this into account, one British Trident submarine has the destructive potential of 768 Hroshima-type explosions. This is roughly seven times the level predicted by the new simulations of regional conflict in India and Pakistan, making it clear that just one British submarine with a full complement of Trident nuclear missiles has the potential to trigger significant and long-lasting global cooling.
The Clock
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The major nuclear powers need to be challenged to respond to these findings. It suits us to focus our thoughts on the global war on terror or regional conflicts rather than on our own hypocritical policies and actions as we silently threaten nuclear obliteration every day.
This information must move out of the technical journals and into mainstream debate and media, and be used to shake people out of a state of complacency about the threat posed by our own nuclear weapons. Armed with the facts, most people could not be persuaded to pay for several global doomsday machines called Trident.
We must challenge the nuclear powers to reduce warhead numbers to a few tens at most and to take the rest off patrol and alert, and put them into verifiable secure storage with inspection. In Britain, this should be a major new component in the “Rethink Trident” campaign.
Chair, Scientists for Global Responsibility
West Yorkshire, UK
“Regional Forecasts” details the effects of nuclear winter based on new work by members of the original TTAPS group, which addressed the climatic effects of a major nuclear exchange between the United States and Soviet Union in the 1980s.
Then as now, critics of the nuclear winter theory said that many of the figures involved in the calculations, such as the number and size of the warheads, their height at detonation, and the location and flammability of targets were unknown and unknowable, and concluded that we needn't act. Most damaging was when Carl Sagan predicted on the news program “Nightline” that smoke from Kuwaiti oil fires would produce massive cooling with damage to agriculture the world over–something that never occurred. In 2000, nuclear winter was listed by Discover magazine as one of the “20 greatest scientific blunders” of the previous two decades. So what are we, as lay people, to make of this controversy, and are things any different now?
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With war, as with other issues of consequence to public health, we must attempt to make predictions, while acknowledging uncertainties, so we can evaluate and minimize potential risks. According to the Health Belief Model, developed by psychologists in the 1950s, individuals take health-related action if they believe that the severity of a consequence is major, that the consequence can be avoided, and that they have the skills and confidence to do so. Public health physician John Last similarly describes social change occurring on public health problems when we are aware that the problem exists, know what causes the problem, believe that it is important, believe in our ability to control the cause, and have the political will to make the changes.
With regard to nuclear winter, there is much we can't know, i.e. changes in the Gulf Stream flow, whether or not dust will shoot straight up into the stratosphere, and how many of what size weapons might be used and on which targets. Nevertheless, we must make decisions based on the best available scientific information.
Societies that do not rule out nuclear first strikes and keep weapons to launch on warning make the threat of nuclear winter real. The fact that our leaders have no plans to eliminate nuclear weapons, are developing new ones, still consider nuclear weapons to be a cornerstone of security, and refuse to negotiate a time-bound framework for their elimination shows that they are not taking all reasonable measures to protect us.
Like climate change, a nuclear exchange could have global catastrophic consequences. This is a problem that must be addressed seriously not just with disaster planning but with preventive techniques, the foremost of which would be abolition of nuclear weapons.
Environment and resource studies
University of Waterloo, Ontario
The key political assumption implicit in recent studies by Brian Toon and colleagues on the effects of regional nuclear war is that if the consequences are seen as sufficiently horrific, then reliance on nuclear weapons must be rethought. Similar assumptions informed nuclear winter studies back in the 1980s, when Carl Sagan and others used the threat of nuclear winter to argue for deep cuts in nuclear arsenals. But such cuts did not occur. Government and military leaders have long been aware of the terrible effects of nuclear war, but many have continued along the nuclear path nonetheless. New studies of the consequences of nuclear war are unlikely to change this. More than knowledge and logic will be needed to reverse governments' attachment to nuclear weapons.
Since the 1940s, concerned citizens and peace movements have stimulated popular concern about nuclear war. As a result, most citizens dread the idea, and indeed did so long before studies of nuclear winter. Most leaders are aware that any government seen to initiate a nuclear attack would suffer an incredible backlash in global public opinion. Further mobilization of popular concern is necessary to make even the possession of nuclear weapons counterproductive for governments.
School of Social Sciences, Media, and Communication
University of Wollongong, Australia
The promise of nuclear energy
The “Bulletin Briefing” in the May/June 2007 issue outlined four major obstacles to a new wave of nuclear power construction. The piece was timely, as it preceded the Group of Eight (G-8) summit of early June, in which climate change was the paramount issue. However, though the extensive media coverage of the summit made much of the G-8 leaders' agreement that “technology” is the best route to reducing greenhouse gas emissions, the word “nuclear” barely surfaced–except as it related to weapons proliferation.
This points to a fifth obstacle to the nuclear renaissance: ignorance, especially among media commentators, about the sheer size of the emissions reductions made possible by shifting power generation capacity from fossil fuels to nuclear.
A case in point: Emissions from coal- and gas-fired power generation in Ontario, my home province, are a major public issue. At their peak in 2003, these emissions were 45.3 million metric tons, according to Environment Canada. Beginning that year, nuclear generating units, moth-balled since the mid-1990s, began to take over a greater percentage of baseload power generation, displacing roughly the same percentage of coal-fired generating capacity in the process. By 2006, total emissions had dropped to about 30 million metric tons, based on 2006 generation and consumption figures from Ontario's Independent Electricity System Operator.
This 15-million metric ton emissions reduction has been the largest in any economic sector in Canada since the country signed the Kyoto Protocol in 1997. It puts Ontario within striking distance of meeting its Kyoto target of 25 million metric tons for the power generating sector. Remarkably, though Kyoto and climate change are as prominent on the public agenda in Ontario and the rest of Canada as they are in Western Europe, almost no one here has noticed or commented on this reduction, let alone its cause.
If proponents of civilian nuclear power really want to achieve the much-touted renaissance in their industry, they have to educate the media.
Ottawa, Ontario
Safeguarding synthetics
It is heartening that Drew Endy and other pioneers in the emerging field of synthetic biology are addressing the security risks posed by the increasing ability to engineer living systems, even as they are motivated by realizing this technology's benefits (“The Bulletin Interview: Drew Endy,” May/June 2007 Bulletin). Of course, the fact that technologies can be both constructively and maliciously applied is not new. But the stakes are particularly high in biology, where advances in science and technology continually increase the power, lower the barriers, and broaden the availability of the means to do harm. DNA synthesis and genomic technologies utilize equipment and materials that are readily available and relatively inexpensive, and they draw on widely accessible databases. These technologies are already fundamental tools of modern biology, constituting an evolutionary improvement in our ability to manipulate DNA. But they also offer the potential for revolutionary advances. Either way, there are no technical chokepoints at which access to these technologies can readily be restricted.
Controlling the malicious application of these technologies must therefore have a social component as well as a technical one. Of course, DNA sequences that are ordered from commercial vendors should be screened to prevent anyone from easily purchasing the means to produce a weapon. At the same time, individuals working with these powerful tools should do so in environments where aberrant behavior or inappropriate activities are more likely to be noticed.
In the past, a professional culture that emphasized scientific autonomy, personal initiative, and individual discretion has yielded extraordinary benefits. However, times change. In the future, researchers and practitioners will need to take more responsibility for monitoring each other's activities, and for being more willing to reveal their own.
A familiar adage states that your right to swing your arm ends where it hits my chin. Well, our arms are a lot longer now. Mouth guards might be part of the solution, but we also need to watch those fists.
Senior fellow for science and security Center for Strategic and International Studies
Drew Endy envisions a future in which the ability to design novel organisms through synthetic biology is as widely accessible as the ability to design novel computer programs. Such a future may bring many benefits, but it also poses risks. The damage that might be wrought by some “biohackers” would be much more difficult to deal with than that caused by their computer hacker brethren.
Endy recognizes that significant security concerns accompany synthetic biology, and his ethical principles are admirable. But ethical prescriptions alone are not enough to ensure that malefactors will be “as few in number and as limited in skill and equipment as possible.” Laws, rules, and regulations–and effective mechanisms for implementation and enforcement–are needed to transform ethical principle into operational practice.
Writing in the journal Nature Biotechnology, Endy and colleagues recently suggested that individuals who place orders with DNA synthesis companies be required to include certain identifying and biosafety information with their orders. In this way, researchers and their institutions would screen the orders against a selected set of pathogens and sequences, and in doing so assume and maintain some accountability for compliance with regulations. Suspicious requests would be reported to government law enforcement agencies.
This proposal should be applauded, but it raises several significant questions: To what meaningful authority would customers and institutions be accountable, and how would accountability be manifested? With what “regulations” would compliance be ensured? At present, there are no regulations. By what criteria could companies reliably identify a “suspicious” synthesis request? What about institutions and facilities that maintain their own internal synthesis capabilities?
In each case, there is a role for laws, rules, and regulations. For instance, the U.S. select agent law, which regulates the possession and transfer of certain pathogens such as anthrax and the ebola virus, could be extended so that only individuals who are registered to handle select agents would be permitted to order select agent genomes. A requirement that all DNA synthesis machines be licensed, and all orders screened, could be enacted. It might make more sense, and be more equitable, if public policy required that all orders for certain types of sequences be automatically reported to governments (with strong privacy provisions). A mandatory system of prior review and approval of all high-risk research projects would greatly strengthen prevention efforts. Evidence of prior approval could be made a condition for receiving certain types of DNA sequences. After all, it is not just what biological agents you are working with, but what you are doing with them and why that matters.
Director, Biological and Chemical Weapons Control Program
Center for Arms Control and Non-Proliferation
As collaborators with Drew Endy on a two-year effort to develop governance options for work with synthetic DNA, we read with great interest the interview with him in the Bulletin. The interview and introduction convey nicely his sense of excitement in the field. However, it does not adequately communicate Endy's seriousness–in fact, leadership–with respect to assuring that the work is carried out in a safe and responsible manner.
Along with other leaders in this field from the Venter Institute, MIT, Harvard, and the University of North Carolina, to name a few, Endy worked with policy analysts, social scientists, legal scholars, and public health experts on a study of synthetic genomics, or the construction of very large (gene- to genome-length) stretches of DNA that can be used to synthesize viruses or bacteria. We, along with Endy and Gerald Epstein at the Center for Strategic and International Studies, convened three workshops to look at the state of synthesis technologies and their potential risks and benefits, and to analyze options for their governance.
Following a large invitational meeting in December 2006, we drafted a final report in which we describe three sets of options for consideration by policy makers. These options are focused on the firms that supply DNA, on registration or licensing regimes for commercially available DNA synthesizers and related reagents, and on the users of the technology and the organizations that support them. Many of these options can be implemented by the synthetic genomics community itself, and such efforts are already underway. Others will only succeed with active involvement by governments.
Policy analyst
Vice president of public policy
The J. Craig Venter Institute
Archiving the Bomb
Regarding Richard Rhodes's “Why We Should Preserve the Manhattan Project” (May/June 2007 Bulletin), the development of the atomic bomb and the introduction of this new energy source surely must be close to the top of significant events in the 20th century. Perhaps it will even be of millennial importance. Those who read about the Manhattan Project in the future can endlessly debate its importance, good and bad, but who could walk and view the sites without feeling the grandeur–or at least the wonder–of what men and women can accomplish when united in effort?
The scientists who developed the theories and the applications will be recognized in their fields forever. But it was more ordinary people working together who constructed the isolated sites, gathered the ingredients, and actually built the Bomb. I would compare my feeling in the presence of these sites to my feeling while standing in the fields at Gettysburg, wondering at the direction or misdirection of ordinary people united for a cause.
How will history judge the Manhattan Project? We are in the midst of trying times, but I am optimistic that these sites will be celebrated positively, not lost in the desert as unimportant.
Park City, Utah
Regarding Richard Rhodes's suggestion that parts of the physical legacy of the U.S. nuclear enterprise be preserved: All over the world, the sites of famous battles that expanded or eroded empires are preserved, to be followed down the centuries by more sites that expanded or eroded later empires. If the answer to Niels Bohr's question to Robert Oppenheimer is yes, and the bombs developed by the Manhattan Engineering District are “big enough” to prevent a third world war, then nuclear sites certainly deserve preservation as the places that changed human concepts about the utility of very large-scale violence.
Fort Collins, Colorado
CORRECTION: The donor recognitions in the July/August 2007 issue of the Bulletin identified Council-level supporters Lee Francis and Michelle Gittler as Lee and Michelle Gittler. With apologies for the error, the Bulletin expresses its gratitude again to doctors Francis and Gittler.