From the January Scientific American:
Twenty-five years ago international teams of scientists showed that a nuclear war between the U.S. and the Soviet Union could produce a “nuclear winter.” … killing plants worldwide and eliminating our food supply. … International discussion about this prediction … forced the leaders of the two superpowers to confront the possibility that their arms race endangered not just themselves but the entire human race. Countries large and small demanded disarmament. Nuclear winter became an important factor in ending the nuclear arms race. … Gorbachev observed, “the knowledge of [nuclear winter] was a great stimulus … to act.”
Why discuss this topic now that the cold war has ended? Because as other nations continue to acquire nuclear weapons, smaller, regional nuclear wars could create a similar global catastrophe. New analyses reveal that a conflict between India and Pakistan, for example, in which 100 nuclear bombs were dropped … would produce enough smoke to cripple global agriculture. … Not only were the ideas of the 1980s correct but the effects would last for at least 10 years, much longer than previously thought. …
More than 20 million people in the two countries could die from the blasts, fires and radioactivity. … A nuclear war could trigger declines in yield nearly everywhere at once. … Around one billion people worldwide who now live on marginal food supplies would be directly threatened with starvation by a nuclear war between India and Pakistan or between other regional nuclear powers.
The effects of a war involving the entire current global nuclear arsenal … [include] a global average surface cooling of –7°C to –8°C persists for years, and after a decade the cooling is still –4°C (Fig. 2). … Cooling of more than –20°C occurs over large areas of North America and of more than –30°C over much of Eurasia, including all agricultural regions.
So, the first news about nuclear winter was shocking enough to induce cold war adversaries to agree to big cuts. Today we know the situation is even worse – not only is nuclear winter easier than we thought to trigger, but more nations now have big enough arsenals to trigger it. Yet today there is far less international discussion or momentum to prevent such disaster. Why the difference?
Perhaps what triggered Western citizen interest last time was not so much that disaster loomed, but that disaster seemed attributable to our moral failings – to our being too belligerent. This time, we don’t feel so belligerent to Russia, and other wars seems like someone else’s fault. Perhaps we care less about anticipating and avoiding disasters, and more about avoiding moral blame for whatever does happen.
Many huge problems loom on a century or so timescale, but the only one that penetrates our public consciousness is global warming. I suspect that is because people see it as attributable to a moral failing of theirs, something like greed, gluttony, or insensitivity to nature. If global warming were just as serious a problem, but caused by an inhuman geological process, I suspect it would get a lot less attention.
If you want the West to attend to a looming future disaster, it seems you must blame it on their current immorality. The disaster I fear most is an unanticipated em transition; how can we blame that on a current moral failing? Imprudence is a moral failing of sorts, but alas it ranks low as a dreamtime concern.
One of the Scientific American's Cold War publishers, Gerard Piel, had a long history of lying and publishing lies about fires from nuclear weapons to attack civil defense readiness, just as his predecessors did in Britain during the 1930s (which made the Prime Minister appease Hitler, encouraging him to start WWII). Typical example of lie:
“A heading in one recent report concerned with effects of nuclear detonations reads, ‘Megatons Mean Fire Storms,’ and the report predicts that a 20-megaton nuclear burst is sure to produce a 300-square mile fire storm. [Reference: Gerard Piel (then the anti-civil defense publisher of the Scientific American), ‘The Illusion of Civil Defense,’ published in the Bulletin of the Atomic Scientists, February 1962, pp. 2-8.] The report further states that blastproof bomb shelters afforded no protection in World War II fire storms, and the reader is left to conclude that vast fire storm areas in which there will be no survivors are an assured consequence of future nuclear attacks. … the 40,000-50,000 persons killed by the fire storm at Hamburg constituted only 14 to 18 percent of the people in the fire storm area and 3 to 4 percent of Hamburg's total population at the time of the attack. … Two of three buildings in a 4.5 square mile area were burning 20 minutes after the incendiary attack began at Hamburg, and similar figures were reported for other German fire storm cities.”
- Robert M. Rodden, Floyd I. John, and Richard Laurino, Exploratory Analysis of Fire Storms, Stanford Research Institute, AD616638, 1965, pages 1, 5.
Media lying about the thermal ignitions (leading to lies about firestorms and nuclear winter caused by the soot of such fires blocking sunlight) can be traced back to the secret classification of the full three-volume 1947 report on Hiroshima by the Strategic Bombing Survey, which was edited out of the brief single volume "summary" that the openly published a year earlier, 1946. Here is the key revelation (originally ‘secret’ May 1947 U.S. Strategic Bombing Survey report on Hiroshima, pp. 4-6):
‘Six persons who had been in reinforced-concrete buildings within 3,200 feet [975 m] of air zero stated that black cotton black-out curtains were ignited by flash heat... A large proportion of over 1,000 persons questioned was, however, in agreement that a great majority of the original fires were started by debris falling on kitchen charcoal fires ...There had been practically no rain in the city for about 3 weeks. The velocity of the wind ... was not more than 5 miles [8 km] per hour.... Hundreds of fires were reported to have started in the centre of the city within 10 minutes after the explosion... almost no effort was made to fight this conflagration ... There were no automatic sprinkler systems in building...’ [Emphasis added.]
Please show me a modern city that is today built out of 1945 Hiroshima style wood frame houses with charcoal stoves amid bamboo furnishings and paper screens. Even Hiroshima is no longer built like that, it's a modern steel, concrete, and brick city and would not suffer a firestorm if a bomb dropped on it again. By the way, the "nuclear winter" from the Hiroshima fire storm blocked out the sun for 25 minutes (from burst time at 8:15 am until 8:40) in Hiroshima as shown by the meteorological sunshine records printed in Figure 6 (3H) of Drs. Ashley W. Oughterson, Henry L. Barnett, George V. LeRoy, Jack D. Rosenbaum, Averill A. Liebow, B. Aubrey Schneider, and E. Cuyler Hammond, Medical Effects of Atomic Bombs: The Report of the Joint Commission for the Investigation of the Effects of the Atomic Bomb in Japan, Volume 1, Office of the Air Surgeon, report NP-3036, April 19, 1951, U.S. Atomic Energy Commission (linked here). There were no reported casualties due to 25 minutes of sunlight deprivation.
So even where city firestorms have actually occurred, there was not a nuclear winter. What about the theoretical predictions that a nuclear attack on oil supplies will cause a nuclear winter, made by the founder of nuclear winter hype, Paul Crutzen? Saddam Hussein’s Iraqi army invaded Kuwait and set all of its oil wells on fire as it was driven back into Iraq by America in 1991.
Peter Aldhous, ‘Oil-well climate catastrophe?’, Nature, vol. 349 (1991), p. 96:
‘The fears expressed last week centred around the cloud of soot that would result if Kuwait’s oil wells were set alight by Iraqi forces ... with effects similar to those of the “nuclear winter” ... Paul Crutzen, from the Max Planck Institute for Chemistry in Mainz, has produced some rough calculations which predict a cloud of soot covering half of the Northern Hemisphere within 100 days. Crutzen ... estimates that temperatures beneath such a cloud could be reduced by 5-10 degrees C ...’
Dr Richard D. Small of Pacific-Sierra Research Corporation, California, responded in Nature, vol. 350 (1991), pp. 11-12, that 16,000 metric tons of actual soot is produced from 220,000 metric tons of oil burned every day, and anyway:
‘My estimates of the smoke produced by destruction of Kuwait’s oil wells and refineries and the smoke stabilization altitude do not support any of the purported impacts. The smoke is not injected high enough to spread over large areas of the Northern Hemisphere, nor is enough produced to cause a measurable temperature change or failure of the monsoons.’
It turned out that the nuclear winter hype was false, because even if you do somwhow manage to start a firestorm in the modern world (the wooden medieval areas of Hamburg and Dresden weren't rebuilt with wood after they burned in firestorms), it simply doen't produce a stable layer of soot in the stratosphere like the computer simulation. At Hiroshima the soot returned to the ground promptly because it is hydroscopic: it forms water droplets, rain. (It wasn't fallout: the firestorm took over 20 minutes to get doing, by which time the radioactive mushroom cloud had been blown miles downwind.)
Robin Hanson asks:
"Do you expect us to believe that the authors of these publications are unaware of these points of yours? Shouldn’t you first try to submit such critiques for publication in similar journals to the articles on the other side, before asking non-expert readers to believe you are more expert than the other authors?"
Well, there are disciplinary issues here, as well as historical ones.
I read with great interest the piece in the _Scientific American_ and I'll willingly grant that the predicted consequences would follow from the assumed causes. However, even a peer-reviewed paper may only have been validated with respect to the disciplinary field it is addressing. A climate science paper will be validated by other climate scientists looking for what *they* find interesting, i.e. a novel way to perturb the climate and original predictions of climatic effects down the line. But the reviewers might not take issue with the underlying assumptions (they would be ignoring the fact that cows aren't spherical and of homogeneous density, to quote an old joke) about the initial conditions.
And while it is purely subjective, I was struck by the authors' insistence that their past work could now be applied to a new and different situation, spanning at least an order of magnitude in distance from the original case study. No, I haven't looked into the issue, but to what extent are they continuing to use the same models they used two decades ago, when computers were much less powerful and simplifying assumptions were absolutely necessary? I'd be leery of rejecting out of hand some of the objections raised above.