Abstract
Ports play a critical role in global sustainability transitions, yet environmental performance reporting remains fragmented and uneven. This study examines environmental key performance indicator (KPI) reporting practices across twenty-five benchmark ports using a multi-category framework encompassing major environmental dimensions. The analysis reveals that, while most ports have established baseline transparency and compliance with international standards, reporting predominantly focuses on inventory-based and infrastructure-oriented indicators, with limited tracking of outcome-oriented performance metrics such as progress toward emissions reduction targets or reductions in stormwater pollution loads. Performance-based, outcome-oriented, and integrative KPIs remain underrepresented across environmental domains. High-level sustainability commitments are frequently disclosed without systematic progress tracking, and environmental domains are often reported in isolation, limiting holistic planning and comparability. Emerging areas such as climate risk assessment, environmental finance, acoustic management, and regenerative design exhibit particularly low reporting maturity. These findings underscore the need to shift from descriptive, compliance-driven disclosures toward harmonized, integrated KPI frameworks that support performance evaluation, strategic decision-making, and systemic sustainability transformation in the global port sector.