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Basin water in deep-silled Norwegian fjords is primarily influenced by inflowing Atlantic water originating from the Norwegian Atlantic Current (NwAC). Previous studies suggest that benthic foraminiferal oxygen isotope records from such fjords are strongly influenced by variability in this current. The present paper presents a mid- to late-Holocene record (6–2.2 ka) with 17-yr time resolution from a western Norwegian deep-silled fjord, Voldafjorden. An age model, based on ten AMS radiocarbon dates on marine carbonates and on one plant macrofossil, has been established. The study focuses on the oxygen isotope results, obtained from two species of benthic foraminifera: Cassidulina laevigata and Uvigerina mediterranea. The δ18O C. laevigata record has systematically larger amplitudes than the δ18O U. mediterranea record, which most likely is related to different life cycles/periods of calcification. The oxygen isotope results show a clear shift towards higher values between 5 and 4 ka, interpreted to reflect a temperature drop in the basin water of c. 1°C. After the temperature drop, the high frequency variability (centennial and multidecadal) changes abruptly towards larger amplitudes. This corresponds to changes in subperiodicity, where a 370 year cycle in the δ18O C. laevigata record disappears after 3.8 ka. The δ18O transition corresponds to changes in carbon isotopes and grain size distribution, suggesting that a more extensive change in the fjord environment occurred after the cooling. The timing of the oxygen isotope shift towards higher values and the transition in high frequency variability correspond to major changes recorded in paleoclimate archives within the North Atlantic region and globally. [ABSTRACT FROM AUTHOR]

Relative sea-level changes in southwest Britain are poorly constrained because of limitations in the quality and quantity of existing geological data. As a consequence, in contrast to most other regions in the UK, it is not possible to reliably infer rates of land and sea-level change during the last few thousand years. Furthermore, geologically based sea-level reconstructions from this area display significant misfits with relative sea-level predictions based on a recent global model of the glacio-isostatic adjustment process. This paper presents a new record of relative sea-level change for the last 4000 years derived from radiocarbon-dated sea-level index points. In addition to providing information concerning the pattern and rates of late Holocene sea-level change, these data are used to evaluate the suggestion that the apparent misfits between model predictions and geological reconstructions can be satisfactorily explained as a consequence of the lowering of sea-level index points by sediment compaction. The results indicate that a simple, first-order method of decompaction based on the stratigraphic position of sea-level index points, can eliminate much of the misfit between reconstructions and predictions, and substantially reduce vertical scatter in geological data. They also suggest that the influence of compaction on sea-level data from this region may be larger than previously thought. The simple addition of reliable stratigraphic data, in combination with targeted sampling, has the potential to improve our understanding of the compaction process, and increase the utility of existing data. This is increasingly important as the partnership between geophysical modelling and geological investigation becomes more commonplace in sea-level studies around the world. [ABSTRACT FROM AUTHOR]