I am still a bit skeptical because I don’t think it would be surprising if the worst case of what can actually happen is actually much less worse than what Robock et al model. I think the search process for that literature was more “worst chain we can imagine and get published”, i.e. I don’t think it is really inherently bound to anything in the real world (different from, say, things that are credibly modeled by different groups and the differences are about plausibility of different parameter estimates).
Yes, since the case for nuclear winter is quite multiplicative, if too many pessimistic assumptions were stacked together, the final result would be super pessimistic. Luísa and Denkenberger 2018 modelled variables as distributions to mitigate this, and did arrive to more optimistic estimates. From Fig. 1 of Toon 2008, the soot ejected into the stratosphere accounting for only the US and Russia is 55.0 Tg (= 28.1 + 26.9). Luísa estimated 55 Tg to be the 92th percentile assuming “the nuclear winter research comes to the right conclusion”:
However, Luísa and Denkenberger 2018 still broadly relied on the nuclear winter literature. Johannes commented he “would not be shocked at all if the risk from nuclear winter would be < 1⁄100 than the estimate of the Robock group”, which would be in agreement with Bean’s BOTEC.
Yeah, that seems the best use of these estimates.
I am still a bit skeptical because I don’t think it would be surprising if the worst case of what can actually happen is actually much less worse than what Robock et al model. I think the search process for that literature was more “worst chain we can imagine and get published”, i.e. I don’t think it is really inherently bound to anything in the real world (different from, say, things that are credibly modeled by different groups and the differences are about plausibility of different parameter estimates).
Yes, since the case for nuclear winter is quite multiplicative, if too many pessimistic assumptions were stacked together, the final result would be super pessimistic. Luísa and Denkenberger 2018 modelled variables as distributions to mitigate this, and did arrive to more optimistic estimates. From Fig. 1 of Toon 2008, the soot ejected into the stratosphere accounting for only the US and Russia is 55.0 Tg (= 28.1 + 26.9). Luísa estimated 55 Tg to be the 92th percentile assuming “the nuclear winter research comes to the right conclusion”:
Denkenberger 2018 estimated 55 Tg to be the 80th percentile:
However, Luísa and Denkenberger 2018 still broadly relied on the nuclear winter literature. Johannes commented he “would not be shocked at all if the risk from nuclear winter would be < 1⁄100 than the estimate of the Robock group”, which would be in agreement with Bean’s BOTEC.
Quick updated. I made a comment with estimates for the probability of the amounts of soot injected into the stratosphere studied in Xia 2022.