In the maritime industry, the vast majority of (GHG) emissions, such as CO2, CH4 and N2O, come from the exhaust gases of shipboard combustion machinery. To improve the robustness of maritime emission estimations, a lifecycle analysis (LCA), which involves the estimation of well to tank and tank to wake of the fuel-related emission, is the commonly accepted norm for estimating the impact of each value chain will be conducted. This work will collect the latest emission factor data for the supply chain of three promising alternative fuels (methanol, ammonia, and hydrogen), and quantitively analyze the emission reduction impact of these fuels in achieving the International Maritime Organization (IMO’s) 2030/2050 GHG reduction goals. Also, the authors developed a green shipping corridor (GSC) framework to evaluate the effects of GSC on GHG emissions. Detailed investigations will involve estimating the current baseline GHG emissions for selected corridors (“Grey Corridors or Business as usual corridors”) followed by estimation of the global warming potential (GWP) performance for identified alternative pathways. It is expected that the study will give additional insights into how these green pathways could play a critical role in maritime decarbonization and what variables are expected to have an outsized impact on emissions. GSC has been identified as an effective green shipping practice to accelerate the maritime decarbonization process. The outputs of this study may serve as solid references for shipping decarbonization strategy development.