Technically “substantial chance of at least 1 billion people dying” can imply the middle option there, but it sounds like you mean the central example to be closer to a billion than 7.9 billion or whatever. That feels like a narrow target and I don’t really know what you have in mind.
I think “crazy large scale conflict (with WMDs)” or “mass slaughter to marginally increase odds of retaining control” or “extreme environmental issues” are all pretty central in what I’m imagining.
I think the number of deaths for these is maybe log normally distributed around 1 billion or so. That said, I’m low confidence.
(For reference, if the same fraction of people died as in WW2, it would be around 300 million. So, my view is similar to “substantial chance of a catastrophe which is a decent amount worse than WW2”.)
I think “crazy large scale conflict (with WMDs)” or “mass slaughter to marginally increase odds of retaining control” or “extreme environmental issues” are all pretty central in what I’m imagining.
I think the number of deaths for these is maybe log normally distributed around 1 billion or so. That said, I’m low confidence.
(For reference, if the same fraction of people died as in WW2, it would be around 300 million. So, my view is similar to “substantial chance of a catastrophe which is a decent amount worse than WW2”.)