Food security under global economic policy uncertainty: fresh insights from the ocean transportation of food

The Russian–Ukrainian conflict has led to ongoing disruptions in global agricultural prices and maritime transport markets, exacerbating food insecurity and raising concerns about the ocean transportation of food. To comprehend this complex relationship, this study employs a vector autoregression model to investigate the time-varying nonlinear connection among global economic policy uncertainty (GEPU), food prices, and maritime transport. Utilizing bivariate and multivariate wavelet frameworks, we validate and explore the lead-lag relationships, co-movements, and dynamic associations among these indicators across various time and frequency domains. The findings reveal a significant covariance among the variables, with medium- and long-term changes being more affected by short-term shocks. Furthermore, there exists both positive and negative interdependence among the variables in the long term, with the interdependence strengthening progressively from the medium to the long term. Notably, the volatility of ocean freight rates has exceeded that of food prices in recent years, thus, impacting future economic policy directions. These results provide a warning to food trade participants as well as governments that focusing on transport market volatility to smooth out food market and economic policy volatility ought to be an important preoccupation, together with increased attention to the potential consequences of global economic policy changes, in order to ensure greater market stability and sustainability in the transportation of food.