Late-Holocene environment and climatic changes in Ameralik Fjord, southwest Greenland: evidence from the sedimentary record

• Main Authors: Møller, Henrik S., Jensen, Karin G., Kuijpers, Antoon, Aagaard-Sørensen, Steffen, Seidenkrantz, Marit Solveig Louise Schramm, Endler, R., Prins, M., Mikkelsen, Naja
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2006
• Subjects: Grønland; Holocæn; klima; fjord; sedimenter; XRF; Greenland; Holocene; climate change; fjords; sedimentary environment; Ameralik; Irminger Sea; Ameralik fjord; North Atlantic; Sea ice
• Online Access: https://pure.au.dk/portal/en/publications/11d6cd50-b1f7-11db-bee9-02004c4f4f50

Sedimentological and geochemical (XRF) data together with information from diatom and benthic foraminifera 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 14 C-dating of benthic foraminifera indicates that the sediment core covers the last 4400 years and may include 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 melt-water discharge from the Inland Ice. The 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 characterised 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.