Ship emissions in the decarbonization era: high-resolution inventories, atmospheric impacts, and air pollution–climate co-mitigation pathways

: Maritime transport is a major component of global trade and an important source of atmospheric pollutants and greenhouse gases. In the decarbonization era, ship emission research is moving beyond conventional emission estimation toward integrated assessment frameworks that connect high-resolution inventories, atmospheric transformation, health and ecosystem impacts, climate forcing, and mitigation pathways. This review focuses primarily on characterizing and quantifying shipping-related primary emissions and emission inventories, which constitute the source term for atmospheric impact assessment. Ambient concentrations and environmental impacts are further governed by plume dispersion, transport, chemical transformation, and secondary pollutant formation. Using a PRISMA-style screening process, this review synthesizes recent advances in ship emission sources, inventory methodologies, spatiotemporal patterns, atmospheric impacts, and air pollution–climate co-mitigation strategies. The evolution of ship emission inventories is first reviewed, from fuel-based top-down approaches to activity-based bottom-up methods and AIS-driven high-resolution models, with emphasis on emission factors, load factors, operating-mode identification, auxiliary-engine and boiler emissions, uncertainty quantification, and multi-source validation. The review then summarizes the spatial and temporal characteristics of ship emissions, highlighting global shipping lanes, regional chokepoints, port-city interfaces, coastal corridors, straits, and island regions. Atmospheric processes and environmental impacts are further examined, including primary pollutants, secondary PM 2.5 formation, nonlinear O 3 chemistry, population exposure, health risks, atmospheric deposition, and climate forcing. The evidence indicates that ship-related impacts are shaped not only by emission magnitude, but also by chemical regimes, meteorology, receptor proximity, fuel quality, and policy context. Mitigation policies and energy-transition pathways are critically assessed, including international regulations, emission control areas, shore power, vessel speed reduction, alternative marine fuels, market-based measures, and Well-to-Wake life-cycle assessment. Overall, ship emission control is shifting from single-pollutant regulation toward integrated air pollution–climate co-mitigation. Future research should prioritize uncertainty-aware high-resolution inventories, observation-constrained emission verification, coupled air-quality–health–climate–economic assessment, AI-enhanced emission modeling, and region-specific strategies for coastal, port, strait, and island environments. An integrated data-to-impact-to-policy framework is essential for supporting cleaner, healthier, and lower-carbon maritime transport.