Reframing maritime through life cycle thinking: evidence, gaps, and future directions
摘要
This study aims to systematically examine the use of life cycle assessment (LCA) in the maritime sector in order to identify methodological trends, the intensity of midpoint impact category usage, and major analytical gaps in the literature. In particular, the study investigates whether the current LCA literature provides a multidimensional understanding of environmental impacts in the context of maritime decarbonization.
MethodsA systematic literature analysis was conducted on 214 maritime LCA-related studies identified through the Web of Science database using a comprehensive set of keywords covering environmental LCA, life cycle cost (LCC), and social life cycle assessment (SLCA). The studies were evaluated through a midpoint category frequency matrix and qualitative methodological review to identify dominant impact indicators, analytical coverage, and structural inconsistencies related to system boundaries, functional units, and data sources.
ResultsThe findings reveal a strong methodological concentration around the climate change indicator, particularly global warming potential (GWP). Approximately 96% of the analyzed studies include GWP, while nearly 40% rely exclusively on this single indicator. In contrast, other environmental impact categories—including acidification, eutrophication, human toxicity, particulate matter formation, water use, resource depletion, and land use—are addressed inconsistently and often treated as secondary considerations. The midpoint category frequency analysis demonstrates a clear “carbon-centrism” within the maritime LCA literature. Furthermore, the study identifies a limited integration of social life cycle assessment (SLCA), indicating a disconnect between the increasing emphasis on a “just transition” in maritime decarbonization discourse and the analytical frameworks currently used in research. Structural challenges such as data heterogeneity, varying system boundaries, diversity in functional units, and a lack of methodological standardization further reduce the comparability of existing studies.
ConclusionsThe study concludes that the current maritime LCA literature remains largely carbon-centric and does not sufficiently capture the multidimensional environmental and social implications of maritime decarbonization. To improve analytical robustness and policy relevance, the literature needs to evolve toward a standardized and multidimensional framework. Developing a policy-grade maritime LCA framework that integrates environmental, economic, and social dimensions would enhance comparability across studies and support evidence-based policymaking in the maritime decarbonization transition.