If there's a nuclear conflict involving >1,000 detonations, will that cause more than 4 billion fatalities within 10 years?

Related Questions on Metaculus:

• If there's a nuclear conflict involving >100 detonations, will that cause >1 billion fatalities within 10 years?

• If there's a nuclear conflict involving >100 detonations, will that cause >1 million fatalities within 1 month?

• If there's a nuclear conflict involving >1000 detonations, will humanity be extinct within 50 years?

• If there's a nuclear conflict involving >1000 detonations, will humanity's population be <400 million 50 years later?

• Will the first nuclear conflict involving >100 detonations cause >100m fatalities within 1 month of the final detonation?

Decisions about how much to prioritize nuclear risk reduction and how best to reduce nuclear risk should be guided in part by our best guesses about:

• how many deaths would occur given a large-scale nuclear exchange

• what proportion of those deaths would occur fairly soon after the detonations (e.g., from the initial blast and fires) rather than later on (e.g., from fallout or nuclear winter effects)

For example, this is relevant to the existential risk posed by nuclear weapons and the value of investing in research and development on "resilient food".

See here, and the sources linked to from there, for previous discussion of these sorts of questions and why they matter.

If there's a nuclear conflict involving >1,000 detonations, will that cause more than 4 billion fatalities within 10 years?

This question will resolve as Yes if:

1. At any point before January 1, 2100, a nuclear conflict begins in which there are more than 1,000 nuclear weapon detonations.

2. For any such conflict, there are more than 4 billion deaths globally in the period between the first nuclear detonation and 10 years after the final detonation of the conflict.

This question is conditional on there being at least one nuclear conflict involving more than one thousand offensive nuclear detonations before 2100. That is, the question will resolve as Ambiguous if that condition isn't met. (But this condition doesn't require that the first nuclear conflict after January 1, 2021 involves more than 1,000 detonations.)

Detonations will be considered to be part of the same conflict if each detonation occurs within 30 days of a previous detonation (even if the detonations involve different state pairings, unrelated motivations, etc.).

If a source gives a range as its estimate, the midpoint of that range will be used as its estimate.

For the purposes of this question, offensive nuclear detonations include deliberate, inadvertent, or accidental/unauthorised detonations (see the fine print for definitions) of state or nonstate nuclear weapons.

[fine-print] This question will also resolve positively if any nuclear conflict meeting the above-mentioned condition clearly causes more than 4 billion fatalities but also causes sufficient civilizational collapse that there are no or extremely few remaining credible sources on any topic. We request that you forecast your true beliefs despite the fact that a Metaculus score seems unlikely to be tracked or cared about in that scenario, given that forecasts on this question may play a role in informing important decisions.

For simplicity, no attempt will be made to second-guess credible sources on what fatalities should be considered to be "caused" by the nuclear conflict.

Detonations for testing purposes and peaceful nuclear explosions are not counted towards positive resolution. Test detonations and peaceful nuclear explosions are defined as detonations which are claimed as being a test or a peaceful nuclear explosion by an official government communication within 30 days of the event, without this being disputed by reliable media, state reports, or multinational reports. If information is unclear, then resolution will be left up to Metaculus admins.

In a deliberate detonation, the attacking nation decides to launch one or more nuclear weapons either in response to a genuine nuclear attack or without believing that it is under nuclear attack. “In an inadvertent detonation, the attacking nation mistakenly concludes that it is under nuclear attack and launches one or more nuclear weapons in what it believes is a counterattack” (Barrett et al., 2013). “In an accidental or unauthorized launch or detonation, system safeguards or procedures to maintain control over nuclear weapons fail in such a way that a nuclear weapon or missile launches or explodes without direction from leaders” (Barrett et al., 2013). [/fine-print]