Prediction suggests that global food production must double to satisfy the increasing demand of world population by the year 2050. Yield enhancement relies heavily on the use of nitrogen fertilizer. However, excess nitrogen fertilizer results in high loss into the atmosphere and/or waterbodies, causing pollution, public-health issues, and long-term greenhouse effect. Climatic disasters such as drought are predicted to pose further threat to agricultural production. Countries will likely further increase nitrogen fertilizer use in the face of climatic risks to ensure crop yield. Then, the question arises - can we design a global food system where 1) food security is ensured and 2) nitrogen loss is minimized (or kept at a reasonably low level)?
Here, using a game-theoretic model, we explore the utility of a central food bank, where countries voluntarily enter by paying a fixed proportion of annual food production. When countries are hit by climatic disaster and cannot meet local demand, they will be compensated by the food bank to ensure food security. We investigate whether the existence of a central food bank allows an increase in food security level while reducing global nitrogen loss, under future climatic risk.
Results/Conclusions
We found that the existence of global food bank effectively reduces global nitrogen loss while sustaining food security under climatic risk. As climatic risk increases, countries are incentivized to enhance fertilizer input, thus increasing global nitrogen loss. Once food bank is established, participants inside the food bank have significantly higher average food security compared to the ones outside the food bank. Since risk of food insecurity is diluted inside the food bank, countries inside the food bank use less nitrogen fertilizer compared to those outside the bank, thus resulting in reduced global nitrogen loss. We also found that there exists an optimal price to punish nitrogen loss for member countries inside the food bank, which allows us to achieve the targeted level of food security while minimizing global nitrogen pollution.