The Southern Ocean plays a key role in the Earth's carbon and heat cycles. Mesoscale features like eddies and fronts are crucial to this but are often unresolved in models due to computational limits. We built a regional NEMO model of the Southern Ocean at 8 km resolution, BIOPERIANT12, which simulates ocean, ice, and biogeochemistry. This helps us investigate dynamics such as how storms shape surface ocean structure and biology, ultimately affecting atmosphere–ocean carbon exchange.