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Abstract: We present the results of an investigation into the potential of salt marshes in the Aasiaat area, West Greenland, for recent relative sea-level (RSL) reconstruction. We use 64 modern diatom samples to develop a transfer function that has a RMSEP of 0.16m and an r 2 of 0.84. We combine these with a similar data set from Sisimiut, 250km south of Aasiaat, standardising the data to account for tidal range differences. An Aasiaat, Sisimiut and a combined model is used to reconstruct RSL change from two recently deposited sediment sections. All three models predict similar RSL change for sediment deposited in low marsh settings, but for sediment deposited in high marsh environments the models differ. Our preferred Aasiaat model reconstructs RSL rise from c. −0.6m at c. 570calyr BP to stabilise within ∼±0.20m of present after 400cal yr BP. Model differences are related to variations in the high marsh/upland vegetation zones, diatom assemblages and organic content between sites that are likely related to differences in tidal range. We conclude that a local transfer-function model is superior to a combined site model for RSL reconstruction in West Greenland. [Copyright &y& Elsevier]

Abstract: Isolation basins, raised tidal marshes, coastal wetlands and dune systems around Arisaig in northwest Scotland produce a ∼16000-year record of relative sea-level (RSL) change from the time of local deglaciation following the Last Glacial Maximum (LGM) to the present. New sea-level index points from Mointeach Mhor North define the culmination of the mid-Holocene RSL highstand to ∼7600–7400calyrBP and 6.74±0.2m above present. Numerous sea-level index points indicate that the RSL highstand persisted more than 1000 years before the onset of any significant RSL fall. This points to a gradual cessation of melting of the Laurentide and Antarctic ice sheets, rather than an abrupt termination. Isolation basin evidence, from a marine limit ∼34 to 38m above present down to sites close to current sea level, constrain the acceleration of eustatic sea-level rise during meltwater pulse 1a to ∼30mmyr−1 or ∼11km3 yr−1 meltwater discharge. Comparison of RSL observations with glacial isostatic adjustment (GIA) model predictions show differences in the pattern of residuals dependent upon the GIA model used. Changes to the far-field ice model components can partly explain the patterns of residuals. [Copyright &y& Elsevier]