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Food system adaptation and maintaining trade could greatly mitigate global famine in abrupt sunlight reduction scenarios

Vasco Amaral Grilo

Alliance to Feed the Earth in Disasters (ALLFED)

vasco@allfed.info

Connect with ALLFED at: www.allfed.info/vicir2023

Risks and Territorial Conflicts.�From natural disasters to geopolitical tensions

23 to 26 of May 2023�Faculty of Arts and Humanities of the University of Coimbra

Coimbra, Portugal

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Mission: help create resilience to global food shocks, with a focus on events that could reduce food supply to households by 5 % or more.
We do academic research, but also preparedness and response plans for governments.
Global team, with members in all continents except Antarctica.
Board members include a billionaire and winner of the Turing Award.
We are looking for collaborators!

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Abrupt sunlight reduction scenarios (ASRSs)

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Abrupt sunlight reduction scenarios

Impact winter

Probability of an asteroid/comet of 1 km or larger colliding with Earth: 0.1 % per century

Ejection of particles into the stratosphere

Reduction of sunlight

Climate change

Volcanic winter

Probability of an eruption with a volcanic explosivity index of 7 or higher: 1/6 by 2100

Nuclear winter

Probability of global nuclear war: 13 % by 2070

Catastrophic event

This reduction in food supply can be caused by abrupt sunlight reduction scenarios (ASRSs).

Causal chain: catastrophic event; ejection of soot into the stratosphere; reduction of sunlight; climate change.

There are 3 types of ASRSs which can cause a food shortfall of at least 5 %:

Impact winter: 0.1 % per century. The asteroid which led to the extinction of the dinosaurs probably caused one.
Volcanic winter: 1/6 by 2100. The eruption of Mount Tambora in 1815 caused the year without the summer in 1816.
Nuclear winter: 13 % by 2070, but note this probability is more uncertain (because we have had impact and volcanic winters in the past, but not nuclear winters).

These are relatively unlikely events compared to floods and storms, but their severity implies they have a major expected damage.

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Conditions during a nuclear winter

Global food insecurity and famine from reduced crop, marine fishery and livestock production due to climate disruption from nuclear war soot injection (Xia et al. 2022, Nature Food)

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3 layers of defence: prevention, response and resilience

Defence in Depth Against Human Extinction: Prevention, Response, Resilience, and Why They All Matter (Cotton-Barratt et al. 2020, Global Policy)

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Food system adaptations to increase resilience against ASRSs

Food system alterations (using conventional sectors more efficiently):

Trade.
Redirect to humans edible inputs to animal feed and biofuels.
Storage.
Culling.

Resilient foods (introducing/expanding sectors):

Cold tolerant crops.
Greenhouse crops.
Seaweed.
Cellulosic sugar.
Methane single cell protein (SCP).

These are helpful for other disasters too (e.g. droughts and floods)

Food system alterations (using conventional sectors more efficiently):

Maintaining trade between countries to ensure the ones with a surplus of food can export to the ones with a deficit.
Redirecting to humans edible inputs to animal feed and biofuels. This is good because one needs more than one calorie of feed in order to produce one calorie of animal products, and biofuels could be temporarily substituted by fossil fuels.
Storing crops for the years of lowest calorie production.
Culling existing livestock populations, such that they could also be eaten during the years of lowest calorie production. This can be achieved via drying/salting/canning the meat.

Resilient foods (introducing new sectors):

Using cold tolerant crops suitable to the nuclear winter.
Large scale deployment of greenhouses to grow crops in a higher temperature.
Rapidly expanding the area of seaweed.
Wood can be converted to cellulosic sugar via a chemical reaction, and paper and pulp factories could be repurposed to grind the wood.
Natural gas can be used to produce methane single cell protein via a chemical reaction.

Note the adaptations on the left can also help with food shocks which are caused by other disasters. For example, more frequent droughts or floods due to global warming.

We parameterised these adaptations in ALLFED’s integrated model.

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ALLFED’s integrated model

Assumptions (among many more):

Cooperation and trade within and across countries.
30 to 300 M$ in preparedness and response plans, and research and development of resilient foods.
People can generally afford the foods produced.

Goal of the linear optimisation:

Maximising the minimum satisfied fraction of human calorie, protein and fat requirements across all months.

Preprint: Rivers et al. 2022. GitHub repository: here.

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Global results for 150 Tg with trade and simple adaptations

Simple adaptations: redirect to humans edible inputs to animal feed and biofuels

Note low-income countries would fare worse

Conclusion: trade and simple adaptations are not enough to prevent major famine.

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Global results for 150 Tg with trade, simple adaptations, culling and storage

Simple adaptations: redirect to humans edible inputs to animal feed and biofuels

Note low-income countries would fare worse

Conclusion: adding culling and storage helps, but not enough to eliminate famine.

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Global results for 150 Tg with trade, simple adaptations, culling, storage and resilient foods

Simple adaptations: redirect to humans edible inputs to animal feed and biofuels

Note low-income countries would fare worse

Conclusion: adding resilient foods can greatly decrease famine.

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Topics for future research (among many more)

A more detailed economic analysis. What will competition do to prices? Will there be the incentives to trade or hoard?
Political analysis. How will countries cooperate? Can this be maintained? What policies will be vital to feeding everyone, no matter what?
What can we do to build resilience into food systems today, while maintaining diet affordability, taste and nutritional value?
What could we do to protect against a loss of industry?

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Food system adaptation and maintaining trade could greatly mitigate global famine in abrupt sunlight reduction scenarios

Vasco Amaral Grilo

Alliance to Feed the Earth in Disasters (ALLFED)

vasco@allfed.info

Connect with ALLFED at: www.allfed.info/vicir2023

Risks and Territorial Conflicts.�From natural disasters to geopolitical tensions

23 to 26 of May 2023�Faculty of Arts and Humanities of the University of Coimbra

Coimbra, Portugal