Emission Dynamics in Maritime Transport within the Blue Economy Framework: Decoupling and Causality Analysis for European Nations

Under the pressure of tightening carbon regulations such as the EU Monitoring, Reporting, and Verification (MRV) framework, this study investigates the environmental adaptation and decarbonization processes of maritime supply chains from a Blue Economy perspective, utilizing a panel dataset of 25 nations encompassing European countries and Türkiye (2008–2024). Accounting for cross-sectional dependence and slope heterogeneity, the analyses (the CCEMG estimator, the Dumitrescu-Hurlin test, and the Tapio index) suggest empirical evidence that the assumptions of the Environmental Kuznets Curve (EKC) hypothesis may not hold within this specific sectoral domain, indicating that economic growth does not spontaneously mitigate maritime emissions. Conversely, the long-run coefficients indicate that port cargo volume growth tends to decouple from emission increases, with the emission growth rate lagging behind sectoral volumetric expansion. This trajectory is consistent with operational efficiency improvements reported in the literature, such as scale economies of ultra-large vessels and slow steaming practices. The bidirectional feedback loop obtained from the panel causality test suggests that environmental performance may increasingly function as an important component of ports’ commercial competitiveness. While a structural divide is observed within the European maritime landscape separating traditional carbon-dependent ports from green-oriented nations, the case of Türkiye displays potential toward becoming a critical low-carbon regional transit corridor, supported by its negative elasticity trend and temporary absolute decoupling performance in 2020. Sustaining these observed decoupling pathways over the longer term may require by strategic steps aligned with the findings. In this regard, establishing a national emission monitoring infrastructure compatible with the EU acquis and mobilizing blue finance mechanisms can be evaluated as a strategic necessity.