The convergence of recent extreme-weather events and international conflicts has heightened concerns about the vulnerability of the global food system to shocks. Yet, it remains unclear what shocks most affect a country’s food supply, and what role trade and other food system characteristics play in mitigating or amplifying negative impacts. Here, using a newly developed global bilateral trade model representing 177 countries and four major staple crops (maize, wheat, rice, soybean), we simulate the food supply, trade and price impacts resulting from climate-related yield variability, and shocks motivated by (i) the Ukraine war, (ii) the recent energy price shock, (iii) observed trade bans, as well as (iv) a compound shock (i-iii together). The energy price shock has the greatest effect of the first three shocks, and dominates the effect of the compound shock across most regions and crops. We find that in many instances trade adjustments can help cope with both supply and price shocks, but that this is shaped by a combination of factors that characterize a country’s coping capacity. If the compound shock occurs at a time of poor global weather for agriculture, the total drop in consumer surplus that year can be over USD 600 billion and affect most countries simultaneously. The modelling approach developed here can be a useful tool to identify vulnerabilities in food systems and to develop targeted strategies to enhance resilience, such as strategic stockpiling, schemes to support domestic production or new trade agreements.

Despite the growing accessibility of international grain and oilseed markets, high production costs and trade frictions are still prevalent, contributing to regional heterogeneities in the landed cost of grain imports. Here we quantify the landed cost for six grain commodities across 3,500 administrative regions, capturing regional cost differences to produce grain and transport it across international borders. We find large heterogeneities in the costs of imported grain, which are highest in Oceania, Central America and landlocked Africa. While some regions have uniform landed costs across sourcing locations, others face cost variations across trading partners, showing large inequalities in access. We find that most regions could benefit from a targeted approach to reduce landed cost while others benefit from a mixed strategies approach. Our results highlight that spatial information on production, trade and transport is essential to inform policies aiming to build an efficient and resilient global agricultural commodity trade system.