A multiproxy palaeoenvironmental reconstruction of Loch Sunart (NW Scotland) since the Last Glacial Maximum

Abstract

AbstractLoch Sunart is located on the NW coast of Scotland and contains a sedimentary sequence that records Lateglacial to Holocene climatic variations. A 12 m core MD04-2833 was acquired in the main basin of the loch sampling this sequence. We present the palaeoenvironmental data and palaeoclimatical scenario based on a multiproxy approach using pollen concentrations, sortable silt variation, lithic fraction and marine benthic foraminifera assemblages. These analyses allow the identification of major climate fluctuations such as cooling events. Global temperature decreases are discriminated from local water temperature decreases due to ice-melting processes by the presence ofElphidium subarcticumand the assemblage ofCassidulina obtusaandHaynesina germanica. Two meltwater pulses (MWP) are distinguished, which correspond to the MWP-Ia (15.5–13 cal ka BP) and MWP-Ib (12.2–10.1 cal ka BP). After the maximum water stratification occurred at 7.5 cal ka BP, full marine conditions were established around 6 cal ka BP, which correspond to the highest relative sea-level reached in the loch.