China's 16th Arctic Expedition Concludes with New Geological and Ecological Data

China's 16th Arctic Ocean expedition has concluded its primary leg as the research icebreakers Xue Long and Xue Long 2 returned to Shanghai after a three-month voyage. Organized by the Ministry of Natural Resources, the mission yielded new findings across the Canada Basin and the Gakkel Ridge, including evidence that challenges traditional plate-cooling models. Scientific crews also conducted large-scale tests of domestically developed autonomous observation hardware, supported international scientific partners, and deployed a notably younger research cohort.

The expedition's geological findings at the ultra-slow-spreading Gakkel Ridge challenge standard assumptions about lithospheric thickening, while oceanographic observations of increased Pacific warm water intrusion offer fresh data on changing Arctic sea-ice dynamics. In parallel, the deployment of domestically designed unmanned ice stations and profiling buoys reflects China's push to establish persistent, independent polar monitoring capabilities.

China's 16th Arctic Ocean scientific expedition concluded its main seaborne phase as the research icebreakers Xue Long and Xue Long 2 returned to port in Shanghai following an expedition lasting nearly three months, state media outlets reported. Organized by the Ministry of Natural Resources, the expedition completed comprehensive surveys across the Chukchi Plateau, the Canada Basin, and the central Arctic Ocean. According to mission organizers, the operation reached record highs in survey scale and overall workload, focusing on marine environmental monitoring, geophysics, and autonomous polar equipment testing. Key scientific findings centered on deep-sea geophysics and changing high-latitude ecosystems. In the eastern sector of the Gakkel Ridge abyssal plain, researchers reported locating a previously undocumented, massive hydrothermal plume field. Geophysical imaging of the ridge acquired a continuous record of lithospheric electrical structure spanning 25 million years. Crucially, researchers found that the lithosphere-asthenosphere boundary extends nearly horizontally at a depth of roughly 60 kilometers, a structural feature that diverges from the thickening predicted by standard plate-cooling models. In the Canada Basin, researchers detected an intensified inflow of subsurface warm water originating from the Pacific Ocean, alongside unexpected concentrations of juvenile polar cod within the high-latitude sea ice zone to the north. These ecological observations shed light on shifts in marine habitats driven by warming and sea-ice retreat. Technologically, the mission served as an operational proving ground for domestically developed observational instruments. Scientific crews carried out large-scale deployments and field evaluations of autonomous polar ecological ice stations and ice-based ocean profiling buoys. The voyage also maintained international scientific links: Xue Long 2 provided icebreaking assistance and fuel support to the French Tara Polar Station during its first winter drifting mission, while also conducting joint fishery surveys with German researchers and sea-ice monitoring alongside Russian scientists. Two additional Chinese expedition vessels, the Jidi and Tansuo-3, remained in the Arctic to complete secondary tasks and are scheduled to return in mid-October. Expedition team leader Wang Jinhui noted that this voyage marked the opening Arctic campaign under China's 15th Five-Year Plan cycle, characterized by a younger scientific workforce where roughly 40 percent were first-time polar researchers and over 70 percent were under age 40.