Is food security an illusion for cities? A system dynamics approach to assess disturbance in the urban food supply chain during pandemics

Abstract Context The urban food security is vulnerable to disturbance along food supply chains because of the relatively long ‘food miles’ and cities' reliance on imported food. Urban food security may be at risk during a pandemic because of the implications of the pandemic on the multiple nodes of a food supply chain, including workforce availability, import availability and consumer demand. Objective This study aimed to investigate the effects of a hypothetical pandemic, typical of what might be seen during other similar market disruptions as well, on the urban food supply chain using Singapore, a city-state, as a case study. Methods Through a system dynamics approach, we simulated the effects of a hypothetical pandemic on the shortage and wastage of vegetables under different scenarios (multiple pandemic waves of different maximum infectivity, consumer hoarding behaviour and import cap). Fresh produce, such as vegetables, presents a unique case compared to grains and canned food because of its relatively short shelf-life which makes stockpiling difficult. Results & Conclusions The comparison of the different scenarios suggested that hoarding behaviour was the main cause of the food shortage rather than an approximately 25% reduction on the vegetable imports during a pandemic. Furthermore, reducing the maximum infectivity generally reduced shortage and wastage. The key leverage points identified were the import cap and the extent of hoarding behaviour during crisis times rather than supplier inventories. Our results suggested that during pandemics or similar catastrophes, more effort should be spent on reducing consumer hoarding behaviour rather than increasing vegetable inventories among suppliers. Our study may provide directions for future pandemic planning to improve cities' food security.