Measuring port activities and lockdown impact using automatic identification system data

This study measures congestion in major container ports and investigates how port characteristics and regional factors influence congestion during the COVID-19 periods. We develop port congestion indicators, including vessel arrivals, vessels staying in a period, waiting time, and service time. First, descriptive analysis reveals significantly higher service and waiting times in 2021 due to global supply chain disruptions. Import/export-focused ports were more affected than transshipment hubs. Short-term events such as labor strikes also substantially impacted port congestion. Next, using econometric analyses, estimated impulse response functions indicate a decrease in the number of ship calls following increased mobility restrictions, with average waiting time at anchorage promptly increasing, while average service time at berth was comparatively less affected by the mobility measures. Additionally, we find significant mobility impacts from neighboring ports, comparable in magnitude to those from the respective ports.