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Abstract

The Antarctic Slope Current (ASC) and Antarctic Coastal Current advect heat, freshwater, nutrients, and biological organisms westward around the Antarctic margin, providing a connective link between different sectors of the continental shelf. However, the timescales over which these currents transport water along the shelf, and the strength and pathways of connectivity around the continent, remain poorly understood. We use daily velocity fields from a global high-resolution ocean-sea ice model, combined with Lagrangian particle tracking, to provide a baseline estimate of advection timescales and improve our understanding of circumpolar connectivity around Antarctica. Analysis of particle trajectory experiments shows that advection around the continent is typically rapid with peak transit times of 1–5 years for particles to travel 90° of longitude downstream. The ASC plays a key role in driving connectivity in East Antarctica and the Weddell Sea, while the Coastal Current controls connectivity in West Antarctica, the eastern Antarctic Peninsula, and along the continental shelf east of Prydz Bay. Crucially, the West Antarctic sector, which has experienced rapid melting, has widespread connectivity with all regions of the Antarctic shelf. These findings assist us in understanding the locations and timescales over which anomalies, such as meltwater from the Antarctic Ice Sheet, can be redistributed downstream.