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The concept of "nuclear winter" is a great example of science gone wrong. As it turns out, the original 1980s report vastly overestimated the amount of combustible fuel in cities and inaccurately estimated both modern nuclear weapon yield and blast size. Nuclear war would not create firestorms capable of injecting soot into the stratosphere and would not cause years-long crop failures. Nuclear war is, in fact, quite survivable.
https://skeptoid.com/episodes/4244
https://www.nature.com/articles/475037b
https://www.quora.com/How-many-nukes-would-it-take-to-cause-...
> Nuclear war is, in fact, quite survivable.
Nuclear winter may be less plausible than people believe but I'm not sure a nuclear war can be described as "quite survivable". The potential disruption to transportation networks that are essential for food distribution and delivery of medical supplies etc would be catastrophic in a nuclear war. I have no doubt that a nuclear exchange would be accompanied by electronic warfare - disruption/destruction of the power grid in the north could kill millions in the winter, especially if the petroleum supplies required to evacuate were also disrupted.
It depends on what exactly is meant by "quite survivable."
Does that mean you'll have a 99% chance to survive even if you do any special preparation? If so, nuclear war definitely does not qualify.
Does it mean you'll have a greater than 50% chance to survive with good preparation? Nuclear war probably qualifies.
Or does it just mean that nuclear war won't result in human extinction? Nuclear war definitely qualifies.
An all-out nuclear war would definitely kill tens of millions immediately, and tens if not hundreds of millions with the after-effects. You may not see years-long crop failures due to nuclear winter, but you'll get the same ultimate effect from lack of fertilizer, machinery, and distribution infrastructure. And fallout. A good chunk of the US's productive agricultural land is downwind from ICBM sites which would be targeted for extremely dirty ground burst attacks.
I think my main worry is how well the economic system would hold up in even a fairly minor attack - given how worried politicians were at the time of the banking crisis (e.g. here in the UK having to put troops on the streets to control public order was considered likely if any of the major banks had gone under) I suspect the answer is "not very well".
I think "survivable" is to be understood on a civilization scale, not for individuals. It would definitely be a calamitous event with massive loss of life - but if you survive the attack itself and can feed yourself and otherwise survive for a few months perhaps, you would have decent odds. I think.
Mad Max survival is still survival.
The Quora link you put says the reason the 1980s report is no longer relevant is the drawdown from Cold War nuke levels.
The Nature letter was written by Russell Seitz, who is also skeptical against the harm cigarette smoking can do, that climate change has, and so on. I don't know of any scientific views not aligning with profits of military contractors and big business that he is not skeptical of. He is associated with the Marshall Insitute, founded by his cousin Fred Seitz, who himself was skeptical of cigarette's harm, global warming, deterioration of the ozone layer etc.
The Skeptoid link references the same thing as the Quora link - that nuclear stockpiles have decreased to where a full-scale war would be less than in the 1980s, when the stockpiles were much higher.
For political reasons, it was necessary from the 1940s to 1980s to minimize fears of the impact of a full-scale nuclear war. I used to have an old Stanford Research Institute report which said that if the US and USSR had a full nuclear exchange, the US would get back to current GNP levels - in five years!
I don't know how this is science gone wrong - two of the links you put say this is no longer applicable due to post-Cold War drawdowns, and the other one is by someone who is skeptical not only of this, but that cigarettes are harmful, that climate change is happening and on and on.
The simplistic 1D climate model and the incorrect fuel loading assumptions are also relevant. And I think we owe it to ourselves to evaluate scientific arguments on their merits instead of trying to imply guilt through association.
Nuclear war certainly isn't desirable, but it doesn't do any good to exaggerate its likely effects.
Thank you for the links. I'll have to read your articles very closely later, but recent climate simulations by Alan Robock at Rutgers and analysis by Ira Helfand at IPPNW and others show that a nuclear autumn, created by 100 15-kT (Hiroshima sized) nukes could cause a famine that affects up to 2B people.
I wrote to Dr. Robock and asked him about his model (explicitly on the record, so I'm not disclosing a private conversation). I asked specifically why did the Iraq oil well fires from the Gulf War not inject soot into the stratosphere and cause climatic effects. He wrote back that the difference lies in the formation of firestorms. I draw from this by implication that he believes there remains enough combustable material to start a firestorm in enough places to matter. It's worth noting that while cities have changed a lot, a firestorm did develop in one of the two Japanese cities bombed. I'll have more to say about this in a month or so once I do more research and review your materials.
Here's a link to some of their work: http://ippnw.org/nuclear-famine.html
These estimates look only cities and their fuel loading.
It would be interesting to see how California would manage during dry 'fire season' if nuclear bombardment caused massive forest fires all over the place. If large fires create massive combined updraft it could be a global catastrophe.
We already know that large-area wildfires sometimes cause firestorms that throw soot into the stratosphere.
Science is a process, not a single event or fact. The fact that the nuclear winter research was inaccurate was exposed by the scientific process as much as it was put forward by it.
Additionally, the absence of nuclear winter does not imply that "nuclear war is quite survivable". Nuclear war is almost certainly survivable, with or without nuclear winter. The question is though: what survives? Even without nuclear winter, crop yields are going to plummet drastically immediately, due to the collapse of world trade, industry, and commerce. And that's a positive feedback loop due to population effects. Our current state of industry and agriculture results in nuclear war causing an initial death-toll followed by a delayed death toll as things settle into a drastically different economic/industrial/agricultural equilibrium. Or, to make things clearer: the sustainable population level of a post-nuclear war scenario is vastly lower than the initial surviving population. What happens after that is still, somewhat thankfully, an open question. The human race may survive, but how long it takes civilization to recover to the same level of technology is unknown. It might take years, decades, centuries, or millenia. Indeed it might never happen, for various reasons. Nuclear war is more than likely going to result in everyone currently alive never seeing this level of technological sophistication, affluence, comfort, etc. in their lifetimes.
> Nuclear war is, in fact, quite survivable.
That's highly debatable. I'm 1/2 way through Command and Control (the book) and one criticism I have throughout for both history (the military and politicos), as well as the author, is no mention of the massive refugee crisis that would emerge as a result of a nuclear war. It makes Mad Max look more realistic, not so much the widespread wasteland, as much as the total breakdown of civil society.
If "civil" society, modern governments, do this thing, they forfeit moral high ground. They've failed. So why wouldn't they be immediately dismantled? Why trust anyone? I think it would be such high order betrayal people would take up a new religion that commands them murder is a gift from god, do it as often as possible in order to survive.
>Nuclear war is, in fact, quite survivable.
Short term, or long term? In the long term, that's a lot of hungry people with no org chart above them. Short term, a lot of people will die, be gravely injured, and probably haunted.
Your definition of survival is pretty opaque.
I don't know the science enough to judge which side of this argument is more likely to be correct. But I do know I felt more comfortable about the approach our leaders took towards nuclear war when everyone was terrified of it vs. the attitude of "Hmm, maybe it isn't so bad... maybe we could win a nuclear war?"
Nuclear Winter won’t matter when spent nuclear fuel pools in those nations undergo meltdowns following sustained losses of offsite power caused by catastrophic damage to the national electrical distribution system. The fuel in a nuclear reactor is marginal relative to SFP loading.
Freeman Dyson wrote about this and his feeling was that it would be similar to the London smog after the war. Which was warm - so his conclusion was it wouldn't be a nuclear winter.
> The concept of "nuclear winter" is a great example of science gone wrong.
It's not science gone wrong. It's an example of politics co-opting and exploiting science because science has the credibility that politics doesn't. The elites wanted to scale back nuclear spending and needed a cover to convince the masses and the soviets to support "denuclearization".
History is full of "science" being exploited to advance a political agenda. One of the most poignant examples is nazi germany using social darwinism to justify their political agenda. Modern global warming scaremongering industry is the newest example of "science" being co-opted for a political agenda.
Certainly, human activity is affecting the environment, but the doomsday nonsense peddled by al gore, dicaprio and the media isn't science, it's a politically driven scaremongering tactic to get the world under one "system" ( carbon tax, trade, etc ).
Carl Sagan’s predictions were really dire. Here’s a three paragraph TLDR of his specific predictions from his 1983 article that brought "Nuclear Winter" into the vocabulary:
—
“Our baseline case, as in many other studies, was a 5000-megaton war with only a modest fraction of the yield (20 percent) expended on urban or industrial targets… In the baseline case, the amount of sunlight at the ground was reduced to… too dark for plants to make a living from photosynthesis.
“Land temperatures, except for narrow strips of coastline, dropped to minus 25 Celsius (minus 13 degrees Fahrenheit) and stayed below freezing for months -- even for a summer war... virtually all crops and farm animals, at least in the Northern Hemisphere, would be destroyed, as would most varieties of uncultivated or domesticated food supplies. Most of the human survivors would starve.
“But what if nuclear wars can be contained, and much less than 5000 megatons is detonated? Perhaps the greatest surprise in our work was that even small nuclear wars can have devastating climatic effects. We considered a war in which a mere 100 megatons were exploded, less than one percent of the world arsenals, and only in low-yield airbursts over cities. This scenario, we found, would ignite thousands of fires, and the smoke from these fires alone would be enough to generate an epoch of cold and dark almost as severe as in the 5000 megaton case. The threshold for what Richard Turco has called The Nuclear Winter is very low.
—
I think the reason the Carl Sagan was widely panned afterwords is that the science was just plain bad. The scale of the predictions he made were so off the charts from almost forty years of previous nuclear experience, that he was obviously was wrong. He predicted essentially the end of the humanity from a mere 100 megatons of nuclear explosions, and yet twenty years before article, the Soviet Union had tested a 50 megaton bomb with no more than the usual local effects.
Using bad science to advance a public policy goal is exactly what got us to the current "distrust of science"
To be clear, the claim was not that 100 megatons themselves would cause climate change, but that 100 firestorms in cities would, and that a 1 Mt bomb would be enough to cause a firestorm (there was one in Hiroshima).
It's not completely clear to me just how bad the science was; like the article says there is still a debate today, so it's not completely settled even now. Wikipedia has a lot of discussion.
5,000 megatons would be enough to destroy every major and semi-major city on the planet, literally.
There are 4,416 cities on the planet with 150k+ population. 10 100kt bombs are more than enough to destroy most cities on the planet, at least when you define "destroy" as "most everything is broken and/or on fire and most people are dead within 1 year's time".
After your 10-nukes-per-city campaign, you've still got another 5,840 100kt bombs left in your 5,000 megaton budget to divide among the largest cities (NYC, Tokyo, Hong Kong, Tehran, etc.).
I'm stating this because I don't think it's too useful to predict the secondary effects (nuclear winter, etc.) of a war so terrible that basically everyone on the planet would already be dead (from blast, fire, etc.) or dying within a year's time (radiation, starvation from infrastructure collapse, etc.).
"Soviet Union had tested a 50 megaton bomb with no more than the usual local effects"
The Tsar Bomba was tested over artic wildereness in Novaya Zemlya, not over a city.
I think celebrity scientists propounding disaster scenarios that have actual poor scientific backing, is one of the reasons why there is still so much skepticism about global warming. It is kind of like the story of the "boy that cried wolf". Scientists have been warning about impending doom so many times in the past, and in general things have never been better for humans on a global scale now. People learned to disregard dire predictions. Now, when there is a real danger, people are skeptical.
I find it weird that scientists get crap from other scientists for speaking publicly. Simple jealousy doesn't explain the vehemence.
As for the politics of the issue, mutual assured destruction has been the working theory since Eisenhower. Those who think strategic nuclear war is winnable, as well as the SDI nutters, are threats to that stability.
I think of it more in terms of the people. Someone doing research on a topic for any length of time probably sees themselves as dedicated (time commitment) and intelligent (PhD and post doc work). They really strongly believe what they believe. And someone else comes along with similar traits strongly believes a different thing.
If a person can acknowledge that this other person is smart and qualified, and recognize that they hold a belief that, if true, implies the believe that the person holds is incorrect. Then they have to deal with being wrong on something they have invested a lot of time into and believed for possibly a very long time.
Throw in a bit of imposter syndrome and I think it would be surprising is people just switched their point of view when presented with an alternative. Instead it sets up this conflict where each party tries really hard to prove the other wrong, and after one or more rounds of that one point of view or the other generally prevails (at least from the perspective of the audience). This is when really good science gets done because it does a great job of neutralizing implicit biases.
Massive retaliation and Mutually assured destruction are different concepts.
During the Eisenhower era U.S. doctrine was so called massive retaliation using a force disproportionate to the size of the attack. It was viable strategy only as long as Soviet Union did not have nuclear parity.
Kennedy realized that massive retaliation was not credible anymore and asked other options. U.S. nuclear strategy changed into so called flexible response strategy. Soviet Union had always relied in the use of tactical nukes. First use of nuclear weapons does not automatically lead to all out nuclear holocaust. There was nuclear escalation ladders even against Soviet Union.
Mutually assured destruction (MAD) is deterrence strategy only against massive decapitation attack.
Today locally limited nuclear war is more likely than ever before. It's part of Russian doctrine if Russia is outmatched in local conflicts. US has nuclear weapons and strategies dedicated for limited nuclear war.
It's not about "speaking publicly", it's about claiming (implicitly, typically) that Science supports a particular side in a political debate. Science very rarely actually has the power to do that - it can advise on how (probably) best to achieve a given outcome under certain constraints.
The political debate of Sagans time was unilateral nuclear disarmament and it fed eagerly on accounts of the horror of nuclear war. The unstated constraint was that it was perfectly happy to accept a significantly less restrained Soviet Union on the world stage. Science can't tell you if that's a good idea or not.
> Simple jealousy doesn't explain the vehemence.
In any industry, if you attack/speak-against my beliefs/views/plans/theories, then I don't like it. Even if you didn't mean too. Even if you didn't know I existed or had those views.
It's not about science, it's about humans defending their worldview and beliefs. Even stamp collecting has this.
Anything people put time/effort into has this.
edit: ChuckMcM does a better job describing this.
When a scientist speaks to the public, they represent (in much of the public's mind, anyway) all scientists in the field, and (arguably, to some extent) science and scientists in general. If they say anything wrong, then that harms the reputation of all of the above. From the perspective of a fellow scientist in the field, the speaker must (a) have made mistakes in his analysis, (b) have taken an approach to his analysis that was sloppy enough to allow such mistakes, and (c) have announced results despite having done an analysis that they should have known was sloppy. In other words, it demonstrates not just incompetence but negligence and a disregard for the truth. These are hateful qualities in a scientist.
This is assuming the case of a scientist who confidently makes incorrect assertions. If they qualify what they're saying—"So far this is what the research says, but it's preliminary, there are a few other tests I'd like to see"—then that's a lot more defensible even if they're wrong. (There is a legendary tendency for reporters to remove all the qualifiers, but at least that's not the scientist's fault.) If they state everything confidently, more confidently than the evidence justifies, but they happen to be right on all their assertions so far, then that may be mildly irritating. If they're intellectually cautious and they're right, and if there are scientists that complain about these people, then that does sound like jealousy.
>I find it weird that scientists get crap from other scientists for speaking publicly. Simple jealousy doesn't explain the vehemence.
I know a physicist who despises Brian Cox with a passion. It's jealousy.
I think it's worth pointing out that the global nuclear arsenal today is about a fifth the size it was when Carl Sagan made this warning. We've made significant progress toward reducing existential risk.
https://en.wikipedia.org/wiki/List_of_states_with_nuclear_we...
It's a fifth of what it was, but yet the ordinance (and "migratory" patterns of civilization to cities/shrinking factory towns, globalized economy) is enough to decimate the population dozens of times over; and suspend modern civilization.
This article is interesting; I would say that it is crucial that such warnings and such "celebrity" scientists enter the public debate (expecting backlash and support and discussion - is this not similar to sharing research within one's academic community?). The public can have their existential dread soothed by the idea of nuclear weapons as defense, but it seems that their understanding of their usage is not sufficient. Sagan or someone needed to provide thoughtful discourse on the repercussions of using the weapon. It does seem great to think your nation can use this powerful tool to attack / ultimately defend its and your existence, but the power of and nature of the weapon requires understanding it. The scale of the weapon is not comprehensible, as much as say a simpler explosive device could be to layperson (voter?).
The advocates of SDI and nuclear did not seem to discuss the repercussions of use, rather the fact that the power is a deterrent and useful against enemies. The repercussions are what limit the use of nuclear as a strategic weapon.
Excerpt from the article: '“People didn’t want to change the way they were thinking of [nuclear] weapons,” he says. “I see an echo of that now. What nuclear winter shows is that they’re not really weapons in the sense that other things are weapons: that you can use them to harm your adversary without harming yourself. People are not really considering that if there really were to be a nuclear conflagration, in addition to how unthinkably horrible it would be in the direct theater of the use of those weapons—say in the Korean peninsula and surrounding areas—there would also be global effects.”' - Grinspoon
'...there would also be global effects."' We can view the earth from orbit; we can be made aware of the fact that all nations are "in this together." So, to add some positivity to the comments thread, here is a video about the "Overview Effect" - maybe increased consumer space travel can help humanity's perspective; what if all major political leaders (G8 field trip!) had to go into space as "training/orientation" for their position...
The absolutely incorrect thing to do is to lie to the public by using your credibility as a scientist to knowingly make up your own incorrect story about the hypothetical effects.
You wonder why so many people don't trust "scientists" when you can see they are clearly lying to push a social cause?
A great mini-doc overview of the same topic:
Also, the 1984 BBC documentary 'On the 8th Day' is worth a look: https://www.youtube.com/watch?v=tCz9zqTTark
Was Carl Sagan aware of just how many nuclear weapons had already been detonated in testing by both countries, as well as by India and China? I don't know the exact number but I do know it's over a hundred. If his models were correct, we'd have already been experiencing a nuclear winter by the 1980's.
Um, no. The tests were rather deliberately located away from cities and avoided creating the firestorms required to raise the massive dust clouds and create the effect. They were also not near-simultaneous.
You probably don't need a high yield if you just nuke a volcano or super volcano https://en.wikipedia.org/wiki/Volcanic_winter
"I do not know with what weapons World War III will be fought, but World War IV will be fought with sticks and stones!" ~Albert Einstein
Winter is coming!
Sorry, couldn't resist.
Worries about nuclear fallout are vastly overstated. If you detonate the weapons at the right altitude, they retain most of their destructive effect without creating long term catastrophic fallout.
> If you detonate the weapons at the right altitude
Yeah and if you detonate the at ground level there is going to be a lot of fallout. Worries are very valid.
Surely that will be considered when employing these weapons in a war.