Navigating global food networks: resilience and sustainability in present and future food systems

Thesis

Global food systems face mounting pressures from climate change, evolving dietary preferences, and shifting trade policies, all of which threaten food security. Understanding how food moves from production to consumption, and identifying the vulnerabilities and environmental impacts embedded in these distribution networks, is essential for building resilient and sustainable food systems. Despite this necessity, there remains substantial empirical uncertainty around the structure of food flows at fine spatial scales, the environmental footprints of the foods we consume, and how future changes in diets, climate, and trade policy may reshape global food systems. In this doctoral thesis, I present three papers that advance this understanding.

In Paper 1, I develop a novel methodological framework to map global cereal flows at subnational scales across 3,536 regions in 195 countries, revealing substantial heterogeneity in regional dependencies and identifying concentration patterns that expose vulnerabilities in cereal flow networks. In Paper 2, I estimate the environmental footprints of approximately 475,000 retail food products across 74 countries, demonstrating that the relative ranking of food categories by environmental impact is consistent across regions – with products containing animal-derived ingredients, coffee, and nuts consistently exhibiting the highest footprints – but that ingredient sourcing can also meaningfully affect a product’s footprint. In Paper 3, I model how bilateral trade flows for 32 crops across 153 countries may evolve through 2050 under alternative dietary, climate, and trade policy scenarios, finding that accommodating large-scale dietary transitions under climate change would require substantial restructuring of global food trade, and that more liberalized trade regimes increase reliance on a smaller set of foreign suppliers alongside efficiency gains.

Overall, I argue that more informed decision-making amid the coupled challenges of climate mitigation and food systems transformation requires attention to several interrelated dimensions of food systems. Among these are the balance between local self-sufficiency and global connectivity; the fact that environmental impacts are driven largely by what is consumed, but also by how food is produced; and the ways in which dietary, climate, and policy pathways may reshape global food flows.

Authors: Jain, S

• DOI: 10.5287/ora-ko7kgq1gv
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English