The causal dynamics between ship calls and environmental quality: A granger causality analysis

Abstract

Background: Maritime transportation has rapidly growth handling more than 80% of International global trade and nearly one million ship calls annually in Indonesia. Considering Indonesia's vast archipelago, shipping is the backbone of its logistics and people mobility. However, it simultaneously degrades the environment quality in certain areas. This study aims to assess the causal dynamics between the frequency of ship call and Environmental Quality Index (EQI) in 25 major Indonesian ports. Methods: This research used time series data from 2014 - 2023 and applied the Granger Causality Test to investigate the predictive causal nexus between variables. Findings: The results indicate that the causal relationship between ship calls and the Environmental Quality Index (EQI) is not uniformly significant across provinces. Significant Granger causality appears only in several major ports, showing regional variation in environmental impact. In these areas, increased ship call frequency tends to precede changes in EQI, suggesting environmental pressure from maritime activity. However, the relationship varies by province due to differences in industrial structure and environmental governance. Evidence of reverse causality—from EQI to ship calls—is generally weak, indicating that environmental quality does not significantly influence maritime traffic. Conclusion: These results provide crucial empirical findings for a geographically targeted, non-uniform policy approach for environmental sustainability in the Indonesian maritime sector. Novelty/Originality of this Article: This research may contribute to the first known attempt to analyze the predictive cause-and-effect relationship between Ship Call and the EQI at the provincial level in Indonesia using the Granger Causality method, offering a preliminary fundamental evidence base for policymakers to balance maritime economic activity with environmental protection.