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 e

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. https://en.wikipedia.org/wiki/Nuclear_winter https://en.wikipedia.org/wiki/Nuclear_winter