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A reconstruction of oceanographic variability of the past 5800 years on the southeast Greenland shelf was obtained by analysing a combined marine sediment record based on two cores from the same site. Cores Fox04G/05R were retrieved from a side basin to a cross-shelf trough connecting the 900 m deep Sermilik Fjord with the Irminger Sea in the northwestern North Atlantic. The record was analysed in terms of grain size distribution, XRF and benthic and planktonic foraminiferal content and the chronology was obtained on the basis of 210Pb and 14C dating. The late-Holocene paleoceanographic variations in the record were characterised by a marked influence from the Irminger Current (IC) at the onset of the record at 5800 cal. yr BP and the regional Holocene Climatic Optimum between 5200 and 4200 cal. yr BP. After 3600 cal. yr BP Neoglacial cooling with increased influence of polar waters from the East Greenland Current (EGC) diminished the influence from the IC. Between 1500 and 700 cal. yr BP, the environment was highly dominated by cold low-salinity water masses characterised by sea ice forming locally and/or transported with an intensified EGC. At 700 cal. yr BP, concordant with the onset of the ‘Little Ice Age’, inflow of IC water masses intensified, notably during short-lived warming episodes of the North Atlantic Current most likely related to a contracted subpolar gyre. At the same time, the EGC polar water transport also intensified leading to a stratified water column on the shelf and this may have favoured entrainment of warm subsurface IC waters. Alternatively, the relatively warm rim of the eastern subpolar gyre may have promoted intense submarine melting of extended Southeast Greenland outlet glaciers at this time, producing enhanced meltwater outflow which favoured estuarine circulation processes maintaining the inflow of IC water masses. [ABSTRACT FROM AUTHOR]

A multiproxy record including benthic foraminifera, diatoms and XRF data of a marine sediment core from a SW Greenland fjord provides a detailed reconstruction of the oceanographic and climatic variations of the region during the last 4400 cal. years. The lower part of our record represents the final termination of the Holocene Thermal Maximum. After the onset of the ‘Neoglaciation’ at approximately 3.2 ka cal. BP, the fjord system was subject to a number of marked hydrographical changes that were closely linked to the general climatic and oceanographic development of the Labrador Sea and the North Atlantic region. Our data show that increased advection of Atlantic water (Irminger Sea Water) from the West Greenland Current into the Labrador Sea was a typical feature of Northeast Atlantic cooling episodes such as the ‘Little Ice Age’ and the ‘European Dark Ages’, while the advection of Irminger Sea Water decreased significantly during warm episodes such as the ‘Mediaeval Warm Period’ and the ‘Roman Warm Period’. Whereas the ‘Mediaeval Warm Period’ was characterized by relatively cool climate as suggested by low meltwater production, the preceding ‘Dark Ages’ display higher meltwater runoff and consequently warmer climate. When compared with European climate, these regional climate anomalies indicate persisting patterns of advection of colder, respectively warmer air masses in the study region during these periods and thus a long-term seesaw climate pattern between West Greenland and Europe. [ABSTRACT FROM AUTHOR]

Sedimentological and geochemical (XRF) data together with information from diatom and benthic foraminiferal records of a 3.5 m long gravity core from Ameralik Fjord, southern West Greenland, is used for reconstructing late-Holocene environmental changes in this area. The changes are linked to large-scale North Atlantic ocean and climate variability. AMS 14C-dating of benthic foraminifera indicates that the sediment core records the last 4400 years and covers the termination of the Holocene Thermal Maximum (HTM). The late HTM (4.4–3.2 ka BP) is characterized by high accumulation rates of fine (silty) sediments related to strong meltwater discharge from the Inland Ice. The HTM benthic foraminiferal fauna demonstrates the presence of well-ventilated, saline bottom water originating from inflow of subsurface West Greenland Current water of Atlantic (Irminger Sea) origin. The hydrographic conditions were further characterized by limited sea ice probably related to a mild and relatively windy winter climate. After 3.2 ka BP lower fine-grained sedimentation rates, but a larger input from sea-ice rafted or aeolian coarse material prevailed. This can be related to colder atmospheric conditions with a decreased meltwater discharge and more widespread sea-ice cover in the fjord. [ABSTRACT FROM AUTHOR]