When Carl Sagan Warned the World About Nuclear Winter (2017)

> Also, many people these days act like the threat of nuclear war went away with the end of the Cold War

Lots of people seem to be convinced that MAD is a sufficient deterrent for nuclear war. Which may be true if your safeguards are perfect and your actors are always rational. But in reality, all it takes is a mistake or a madman to set off nuclear armageddon.

Threads is a very good movie. Potential viewers should know that it's old and the special effects have not held up well, but it very much captures the terror of nuclear conflict quite well.

I had a high school teacher show us Threads during a breakout portion of 10th grade history where, for 9 weeks, you learned all about nuclear war. It has stuck with me my entire life. Somewhere about 2/3 of the way through the course we watched the film. It singlehandedly hammered into me what weeks of still imagery, theory, and historical facts could not.

What you learn most importantly from it is, while the initial hyper-violent effects of a proper nuclear war are so much more horrendous than anything humanity can imagine based on anything ever seen prior, it's the slowly diminishing quality of life that spirals out from it that reminds you of the futility and pointlessness of it all. When, ten years later, you see life is operating at medieval (or worse) levels, it's a truly crushing feeling.

The film is available on Amazon (for purchase only), I believe. Everyone should watch it, but I cannot emphasize enough that for some people it can be a real stressor. It has no happy ending.

FYI you can watch it here: https://tubitv.com/movies/531445/threads

Another effective film in the same genre is "The Day After."

https://en.wikipedia.org/wiki/The_Day_After#Effects_on_polic...

>President Ronald Reagan watched the film more than a month before its screening, on Columbus Day, October 10, 1983.[28] He wrote in his diary that the film was "very effective and left me greatly depressed,"[29][25] and that it changed his mind on the prevailing policy on a "nuclear war".[30] The film was also screened for the Joint Chiefs of Staff. A government advisor who attended the screening, a friend of Meyer's, told him "If you wanted to draw blood, you did it. Those guys sat there like they were turned to stone."[citation needed] Four years later, the Intermediate-Range Nuclear Forces Treaty was signed and in Reagan's memoirs he drew a direct line from the film to the signing.

If you haven't read it yet, I highly recommend The Doomsday Machine: Confessions of a Nuclear War Planner, by Daniel Elsberg.

It's terrifying but highly informative.

Ann Druyan, Sagan’s wife, responded to this article with the following:

> Lepore has done history and science, your readers, and my late husband, Carl Sagan, a great disservice. Her article’s central thesis demeans Carl’s scientific acumen and his character, wrongly asserting that, in his “grandiosity,” he harmed the environmental movement by advancing an exaggerated theory of the long-term consequences of nuclear war.

> From Lepore’s account, readers would conclude that Carl’s interest in the greenhouse effect on Venus was something that he picked up from a bright grad student. In fact, five years earlier, Carl had published his own dissertation, viewed as the beginning of our modern understanding of Venus, which included his groundbreaking greenhouse model.

> Lepore also gives the impression that the theory of nuclear winter has been debunked. If anything, more recent scientific research indicates that Carl and his colleagues were conservative in their estimates. Tellingly, she makes no reference to the findings—in peer-reviewed, refereed publications—that fully support, and expand on, the models created by Carl and the other nuclear-winter scientists.

> Carl is also faulted for “partisanship,” in part for declining an invitation to dine with the Reagans in the White House—a choice that I made, in response to the El Mozote massacre and other crimes in Central America for which I believed Reagan bore some responsibility. Does Lepore find those public figures and celebrities who refuse to be co-opted by the Trump White House to be partisan? Or is that an unwillingness to lend your cachet to policies that you abhor?

> According to Lepore, Sagan “made some poor decisions” and “undermined environmental science.” She leaves the reader to wonder what those bad decisions were. Fighting for the reduction of tens of thousands of nuclear weapons? Sounding the alarm on global warming decades before others started paying attention to it? Mounting the world’s most successful campaign for public scientific literacy? Attracting multitudes to science and reason? Turning the camera on Voyager 1, which was out by Neptune, to point homeward, to make us see our true circumstances in the vastness? What better decisions have other people made?

> Ann Druyan

> Ithaca, N.Y.

—https://www.newyorker.com/magazine/2017/02/27/letters-from-t...

Same, well not winter, I assumed I'd die in initial strike living near major targets.

I, and many people of similar age I've talked with since, did not believe they would live into adulthood. Believing nuclear war was imminent and inevitable.

> According to the article, it wouldn’t take both major nuclear powers firing all their weapons to create a nuclear winter. Even a smaller-scale war could destroy humanity as we know it.

I'm skeptical of this; in the 20th century there were more than 500 atmospheric nuclear tests. Given that, it seems unlikely that a ""small"" nuclear war would necessarily cause such dramatic effects as humanity-destroying nuclear winter. This said, cities getting nuked would probably launch more soot into the atmosphere than the desert or ocean getting nuked, so... maybe?

But I think we should try to avoid finding out for sure. ;)

The current consensus of nuclear winter is probably summed up as "if nuclear weapons turns cities into giant stratospheric soot pumps, we're screwed; if they don't, we've just reversed global warming for a few years."

Looking for recent research, there seems to only be one group modelling nuclear winter scenarios, and those papers seem to be using the 1980s-era numbers for soot generation without commentary on how valid those assumptions are (other than to say that it's contentious) [1]. I don't see any papers directly discussing soot generation in relation to nuclear winter, and I suspect our large-scale fire modelling is not yet capable of answering the question of what the resulting fire from a nuclear warhead strike on NYC would look like.

I'm personally on the side that thinks the stratospheric injection of large-scale metropolitan fires is wildly overestimated (the Kuwaiti oil fires failing to reach that level being evidence of that point), which means that the risks of nuclear winter

[1] And the paper itself has a section on implications for nuclear policy, which sets off motivated-to-reach-a-conclusion research alarm bells for me.

The anthropic principle?

https://www.lesswrong.com/posts/KNtKKmcd9DsP7WuZ3/the-anthro...

We came uncomfortably close sometimes. Like the Russian submarine commander who defied his "party supervisor" when ordered to launch his nuclear weapons during the Cuban missile crises. It was not an isolated incident either. We've been lucky so far.

Luck.

In the short period of time we have had access to nuclear weapons, we have come very close to nuclear war between superpowers:

* Cuban Missile Crisis - Vasili Arkhipov Prevents launching of nuclear torpedo while his Soviet submarine flotilla is being bombarded by depth charges (happened to be signaling depth charges). Turns out the US warships above them just wanted the submarines to surface so they could communicate the end of hostilities.

* Computer Malfunction - Stanislav Petrov Holds off alerting officials of multiple incoming nuclear ICBMs because he "suspected" they were a glitch, preventing a likely nuclear counter-attack.

* Science experiment looks like nuclear attack - Boris Yeltsin correctly decides to wait launching a counter-attack based on an incoming rocket. All the while sitting in front of an activated nuclear briefcase and being pressured by aids to launch within the 12 minute response window. The rocket was meant for atmospheric testing.

There are many, many more.

Proliferation means more and more nation states have access to nuclear weapons. Balancing peace amongst all those nations can be difficult (look at India and Pakistan). Countries with existing nuclear stockpiles can undergo dramatic shifts in leadership and policy (US politics anyone?).

We also have 7.5+ billion people on the planet, consuming more resources than ever, on a planet with a finite amount of things.

Now throw in the further ramifications of climate change like political instability, infrastructure strain, resource scarcity, and refugee migrations into the mix. Or a truly mad guy with a nuke.

There are way too many people out there that are crazy optimistic that we aren't going to have a nuclear war...ever. We have always had warfare, and when the shit hits the fan, armies have always used the biggest weapons they have had.

Nuclear weapons may very well be our great filter.

If you're an optimist, there is the view that neither side of the Cold War wanted to die. Excluding the truly religious people who believe that dying and going to heaven is better than being alive, most people want to avoid their own deaths. When politicians believed they could send soldiers off to kill without risking their own lives, they started wars. But since ICBMs meant than starting a ground war against a nuclear power put the leaders at risk, the leaders chose relative peace and deescalated when possible.

The cost is simply too high and even the leaders that were popularly perceived as being unstable haven't been that unstable.

If it had happened we wouldn't be here. This is one thing that takes me an inch closer to believing the quantum suicide hypothesis and maybe even higher powers. We rolled the dice so many times and they kept coming up 7 over and over again.

Such an absurd situation.