Relative Sea-Level Change, Tidal Evolution and Energy Dissipation Across the Patagonian Shelf Since the Last Glacial Maximum

Tides play a key role in regulating shelf-sea environments, influencing sediment dynamics, habitat distribution, long-term carbon burial, coastal hazards, and water quality, with important socio-economic consequences. Yet the long-term evolution of shelf sea tides in response to sea-level change remains poorly understood. We have developed the first regional paleotidal reconstruction for the Patagonian Shelf, one of the most tidally energetic regions globally, supporting high primary productivity and sustaining rich food webs. The model incorporates updated relative sea-level reconstructions and is driven by global paleo-ocean forcing. Tidally modulated parameters are produced at 1,000-year intervals from the Last Glacial Maximum (21,000 years ago) to the present. The reconstruction shows how tidal dynamics across the shelf are sensitive to relative sea-level change. Overall, present-day tidal dynamics are relatively energetic compared with much of the deglacial period. Tidal energy dissipation responded non-linearly to shelf inundation, with changes in coastline configuration and water depth driving abrupt reorganizations of regional tidal dynamics and associated frictional hotspots. The M2 tidal energy dissipation dominated throughout, peaking at 10 ka BP (+16% relative to present-day). Dissipation for O1 was highly sensitive to shelf evolution, peaking at ∼50% above present-day at 15 ka BP. This work establishes a baseline for future interdisciplinary studies, providing open-access simulations that improve interpretation of sea-level indicators, long-term coastal evolution, environmental archives, and seabed management across the Patagonian Shelf.