A high‐resolution Lateglacial and Holocene palaeoceanographic record from the Greenland Sea

Abstract

We present an unprecedented multicentennial sediment record from the foot of Vesterisbanken Seamount, central Greenland Sea, covering the past 22.3 thousand years (ka). Based on planktic foraminiferal total abundances, species assemblages, and stable oxygen and carbon isotopes, the palaeoenvironments in this region of modern deepwater renewal were reconstructed. Results show that during the Last Glacial Maximum the area was affected by harsh polar conditions with only episodic improvements during warm summer seasons. Since 18 ka extreme freshwater discharges from nearby sources occurred, influencing the surface water environment. The last major freshwater event took place during the Younger Dryas. The onset of the Holocene was characterized by an improvement of environmental conditions suggesting warming and increasing ventilation of the upper water layers. The early Holocene saw a stronger Atlantic waters advection to the area, which began around 10.5 and ended quite rapidly at 5.5 ka, followed by the onset of Neoglacial cooling. Surface water ventilation reached a maximum in the middle Holocene. Around 3 ka the surface water stratification increased leading to subsequent amplification of the warming induced the North Atlantic Oscillation at 2 ka.

Water mass evolution of the Greenland Sea since late glacial times

“…1). Core PS1878 is compiled from a giant box core PS1878-2 and a kasten core PS1878-3 (Telesiński et al, 2013), whereas the three others are giant box cores (Table 1). All cores consisted of brown to olive grey sediments of clay to silty sand.…”

“…This is best illustrated by relatively old ages yielded from the surface samples of these cores (2.3-3.8 ka). However, the surface sample of core PS1878 yielded a younger age (0.426 ka) and contained recent sediments (Telesiński et al, 2013). Therefore we assume that sedimentation in the entire study area did not terminate in the late Holocene.…”

“…While a significant number of detailed studies focuses on the eastern part of the region, along the North Atlantic Current (NAC) flow (e.g., Hald et al, 2007;Risebrobakken et al, 2011), less effort has been devoted to its central and western parts (e.g., Fronval and Janssen, 1997;Bauch et al, 2001). Problems with the accessibility due to the ice cover and low sedimentation rates (Nørgaard-Pedersen et al, 2003;Telesiński et al, 2013), which do not allow high resolution studies, are among the main reasons here.…”

“…Recently, Telesiński et al (2013) presented a new record from the central Greenland Sea that allowed studying the oceanographic changes since the late glacial (22.3 ka) in a relatively high temporal resolution. That study revealed significant variability of the oceanic environment on multicentennial to multimillennial timescales.…”

“…A detailed description of site PS1878 was given by Telesiński et al (2013). The three sites from the northern Greenland Sea, PS1894, PS1906 and PS1910, are located on the Greenland continental slope, on the northern and on the southern part of the Greenland Fracture Zone crest, respectively.…”