In the report a footnote 2 states: ”In mild agricultural shortfalls such as those that may be triggered by crop blight, VEI-7 volcanic eruption or extreme weather, adaptations like redirecting animal feed, rationing and crop relocation would in theory be sufficient to feed everyone”.
How did you come to that conclusion? We’re only aware of 1 academic study (Puma et al 2015) about food losses from a VEI 7 eruption and it estimates 1-3 billion people without food per year (I think this is a likely an overestimate, and I’m trying to do research to quantify this), so just trying to figure out what you’re basing the above statement on, does this take into consideration food price increases and who would be able to pay for food (even if there is technically enough)?
Also note the use recurrence intervals of super eruptions is an order of magnitude off from Loughlin paper which has since been changed (see discussion here: https://forum.effectivealtruism.org/posts/jJDuEhLpF7tEThAHy/on-the-assessment-of-volcanic-eruptions-as-global ). Also note, VEI 7 eruptions can sometimes have the same/if not greater climatic impact as super-eruptions, as the magnitude scale is based on the quantity of ash erupted whilst the clmatic impact is based on the amount of sulfur emitted (which can be comparable for VEI 7 and 8 eruptions). I mention these as whilst nuclear war probabilities have huge uncertainties, our recurrence intervals from ice cores of large eruptions are now well constrained, so it might help with the calcs.
From a quick scan through Puma et al 2015 it seems like the argument is that many countries are net food importers, including many poor countries, so smallish shocks to grain production would be catastrophic as prices rise and importers have to buy more and at higher prices which they can’t afford. I agree that this is a major concern and that it’s possible that a sub-super eruption could lead to a large famine in this way. When I say “adaptations like redirecting animal feed, rationing and crop relocation would in theory be sufficient to feed everyone” I mean that with good global coordination we would be able to free up plenty of food to feed everyone. That coordination probably includes massive food aid or at the least large loans to help the world’s poorest avoid starvation. More importantly, resilient food sources don’t seem like a top solution in these kinds of scenarios. It seems cheaper to cull livestock and direct their feed to humans than to scale up expensive new food sources.
Thanks for the link—now you mention it I think I read this post at the beginning of the year and found it very interesting. In my analysis I’m assuming resilient foods only help in severe ASRS, where there are several degrees of cooling for several years. Do you think this could happen with VEI 7 eruptions?
I couldn’t find the part where the Loughlin paper has been changed. Could you direct me towards it?
Hi Stan, thanks for your response. I understand your main thesis now -seems logical provided those ideal circumstances (high global co-operation and normal trade).
VEI 7 eruptions could lead to up to 2-3 degrees of global cooling for ~5-10 years (but more elevated in the northern hemisphere). See here: https://doi.org/10.1029/2020GL089416
More likely is two VEI 6 eruptions close together, which may provide longer duration cooling of a similar amount ~2 degrees, like in the mid 6th century (Late antique ice age).
The Loughlin chapter didn’t account for the incompletness of the geological record like papers published since have done with statistical methods (e.g. Rougier paper I cite in that post), or with ice cores that are better at preserving eruption signatures compared with the geological record.
In the report a footnote 2 states:
”In mild agricultural shortfalls such as those that may be triggered by crop blight, VEI-7 volcanic eruption or extreme weather, adaptations like redirecting animal feed, rationing and crop relocation would in theory be sufficient to feed everyone”.
How did you come to that conclusion? We’re only aware of 1 academic study (Puma et al 2015) about food losses from a VEI 7 eruption and it estimates 1-3 billion people without food per year (I think this is a likely an overestimate, and I’m trying to do research to quantify this), so just trying to figure out what you’re basing the above statement on, does this take into consideration food price increases and who would be able to pay for food (even if there is technically enough)?
Also note the use recurrence intervals of super eruptions is an order of magnitude off from Loughlin paper which has since been changed (see discussion here: https://forum.effectivealtruism.org/posts/jJDuEhLpF7tEThAHy/on-the-assessment-of-volcanic-eruptions-as-global ). Also note, VEI 7 eruptions can sometimes have the same/if not greater climatic impact as super-eruptions, as the magnitude scale is based on the quantity of ash erupted whilst the clmatic impact is based on the amount of sulfur emitted (which can be comparable for VEI 7 and 8 eruptions). I mention these as whilst nuclear war probabilities have huge uncertainties, our recurrence intervals from ice cores of large eruptions are now well constrained, so it might help with the calcs.
Thank you for your comment!
From a quick scan through Puma et al 2015 it seems like the argument is that many countries are net food importers, including many poor countries, so smallish shocks to grain production would be catastrophic as prices rise and importers have to buy more and at higher prices which they can’t afford. I agree that this is a major concern and that it’s possible that a sub-super eruption could lead to a large famine in this way. When I say “adaptations like redirecting animal feed, rationing and crop relocation would in theory be sufficient to feed everyone” I mean that with good global coordination we would be able to free up plenty of food to feed everyone. That coordination probably includes massive food aid or at the least large loans to help the world’s poorest avoid starvation. More importantly, resilient food sources don’t seem like a top solution in these kinds of scenarios. It seems cheaper to cull livestock and direct their feed to humans than to scale up expensive new food sources.
Thanks for the link—now you mention it I think I read this post at the beginning of the year and found it very interesting. In my analysis I’m assuming resilient foods only help in severe ASRS, where there are several degrees of cooling for several years. Do you think this could happen with VEI 7 eruptions?
I couldn’t find the part where the Loughlin paper has been changed. Could you direct me towards it?
Hi Stan, thanks for your response. I understand your main thesis now -seems logical provided those ideal circumstances (high global co-operation and normal trade).
VEI 7 eruptions could lead to up to 2-3 degrees of global cooling for ~5-10 years (but more elevated in the northern hemisphere). See here: https://doi.org/10.1029/2020GL089416
More likely is two VEI 6 eruptions close together, which may provide longer duration cooling of a similar amount ~2 degrees, like in the mid 6th century (Late antique ice age).
The Loughlin chapter didn’t account for the incompletness of the geological record like papers published since have done with statistical methods (e.g. Rougier paper I cite in that post), or with ice cores that are better at preserving eruption signatures compared with the geological record.