The Northeast Passage (NEP) holds immense potential as a link for maritime transport activities between Europe and Asia, primarily due to the extended sailing season resulting from global warming. However, the economic viability of the Arctic shipping route remains disputed. This study aims to comprehensively evaluate the feasibility of container transportation along the NEP compared to that along the Suez Canal Route (SCR) by using current (2021-2023) and future (2025-2065) scenarios. The results reveal that larger vessels have lower CO2 emissions and costs than small vessels in the NEP, but the costs for larger vessels in the NEP are still higher than those in the SCR throughout both summer and winter seasons under the current scenario. The outcomes also show that a progressive carbon tax scheme will increase the unit shipping costs for all routes in the future scenario, with the NEP being most economically viable during summer. Furthermore, the extended navigable period (NP) bolsters the NEP's economic cost advantage during a seasonal period. Nevertheless, from a year-round operations standpoint, the NEP remains less competitive than the SCR before 2065. The conclusions drawn from this research serve as a significant resource for decision-makers when formulating operational plans.

The navigation potential of the Arctic has improved with the rapid retreat of sea ice under continuous warming. The comprehensive evaluation of Arctic accessibility for low ice-breaking ships (civil use) in the mid-century is important to support coordinated international decision-making. In this study, the hydrological conditions and navigation potential in key areas and crucial straits along the Northern Sea Route (NSR) and Northwest Passage (NWP) were assessed under Shared Socioeconomic Pathways (SSPs) using the Polar Operational Limit Assessment Risk Indexing System. The results showed that the most critical areas for navigation in the mid-century (2046-2055) are the waters around the New Siberian Islands and within the Parry Channel. Arctic navigability improves from SSP1-2.6 to SSP2-4.5 to SSP5-8.5, and the accessibility for PC7 ships under SSP2-4.5 is even better for OW ships under SSP5-8.5. The route on the north side of the New Siberian Islands is a relatively good choice within the NSR, and the southern route has a better navigation potential than the Parry Channel within the NWP. In addition, the accessibility of the Dmitrii Laptev Strait is better than that of the Sannikov Strait at a monthly scale, although the latter has more navigable days. However, there is little difference in accessibility between the eastern and western parts of the Parry Channel. The best navigation potential through the above straits is in September for ordinary ships, and the optimal time window is delayed and extended for PC7 ships. The results can serve as references for policy-making and navigation planning in the Arctic.