Summary: | Northwest Scotland and the Isle of Skye host significant records of Quaternary environmental change. Providing constraints of relative sea-level (RSL) change at local and regional scales since the Last Glacial Maximum is critical not only for understanding coastal evolution and the rate and magnitude of RSL changes, but also for informing patterns of deglaciation, and the refinement of glacio-isostatic adjustment (GIA) models. For the southern Isle of Skye we identify a marine limit at ~23m OD, indicating RSL ~20m above present c. 15.1 ka. Isolation basin data, supported by terrestrial and marine limiting dates, record an RSL fall to 11.59 m above present by c. 14.2 ka. This RSL fall occurs across the time of global Meltwater Pulse 1A, supporting recent research on the sources of ice melting. The new data help to resolve some of the chronological issues of age overestimation within the existing Isle of Skye RSL record, and provide details of the sub‐Arctic marine environment associated with the transition into Devensian Lateglacial climate at c. 14.5 k cal a BP. GIA model predictions of RSL in southern Isle of Skye deviate from the RSL constraints and reflect uncertainties in local and global ice models used within the GIA models. Near Gairloch, Wester Ross, RSL records indicate a fall from a marine limit ~20 m above present at c. 16.1-16.5 ka, and new data from three isolation basins record RSL fall over the following c. 0.8 ka. The new and existing records of RSL change obtained from isolation basins in Wester Ross along the flanks of the former Minch Ice Stream provides insights into the nature of deglaciation and RSL change, and a test of GIA predictions of the RSL history for the region.
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