关键词: 东边界上升流, 气候模式分辨率, CMIP6, 埃克曼输运, 地转输运

Abstract: As one of the most productive regions in the global ocean, eastern boundary upwelling systems (EBUSs) play a crucial role in maintaining marine ecosystems and supporting global fisheries. However, traditional low-resolution climate models exhibit substantial biases in these regions, limiting reliable assessments of upwelling processes and their future changes. Using simulations from the CMIP6 High-Resolution Model Inter-comparison Project (HighResMIP), this study evaluates the extent to which increased spatial resolution improves the simulation of the four major EBUSs worldwide and examines the differences between dynamical and thermal indicators for characterizing upwelling in both historical simulations and future projections. The results show that low-resolution models generally underestimate the strength of coastal upwelling, whereas increasing spatial resolution?particularly the ocean model resolution?significantly reduces these biases. Higher resolution effectively improves the simulation of Ekman-driven upwelling processes, although the representation of geostrophic transport remains challenging. Meanwhile, high-resolution models also demonstrate clear improvements in reproducing thermally based upwelling indicators. Future projections indicate pronounced regional differences in the response of EBUSs to global warming, while increased model resolution does not substantially reduce the spread among model projections. Overall, increasing model resolution significantly improves the representation of the mean state of EBUSs, but considerable uncertainties remain in their future projections, and the underlying dynamical mechanisms require further investigation.

Key words: Eastern boundary upwelling systems (EBUSs), Climate model resolution, Coupled Model Intercomparison Project Phase 6 (CMIP6), Ekman transport, Geostrophic transport