Skip to main content

Research Repository

Advanced Search

Holocene palaeoceanographic evolution off West Greenland

Perner, K.; Moros, M.; Jennings, A.; Lloyd, J.M.; Knudsen, K.L.

Holocene palaeoceanographic evolution off West Greenland Thumbnail


Authors

K. Perner

M. Moros

A. Jennings

K.L. Knudsen



Abstract

Benthic foraminiferal assemblages from a core southwest of Disko Bugt provide a Holocene perspective (last ~7 ka BP) on ice-sheet/ocean interactions between the West Greenland Current (WGC) and the West Greenland ice sheet. Changes in the fauna reveal significant variations in the water mass properties (temperature and salinity) of the WGC through time. From 7.3 to 6.2 ka BP, a relatively warm/strong WGC influences ice-sheet melt in Disko Bugt and causes enhanced meltwater production, resulting in low surface-water productivity. The most favourable oceanographic conditions occur from 5.5 to 3.5 ka BP, associated with ‘thermal optimum-like’ conditions, encompassing minimum ice sheet extent in the Disko Bugt area. These conditions are attributed to: (1) reduced meltwater influence as the ice sheet is land based and (2) enhanced contribution of warm/saline water masses from the Irminger Current to the WGC. The transition into the late Holocene (last ~3.5 ka BP) is characterized by a cooling of oceanographic conditions, caused by increased advection of cold/low-salinity water masses from the East Greenland Current. A longer-term late-Holocene cooling trend within the WGC is attributed to the onset of Neoglacial cooling within the North Atlantic region. Superimposed on this cooling trend, multicentennial-scale variability within the WGC matches reconstructions from a nearby coring site in Disko Bugt as follows: (1) cooling at ~2.5 ka BP, linked to the 2.7 ka BP ‘cooling event’; (2) a warm phase centred at 1.8 ka BP, associated with the ‘Roman Warm Period’; (3) slight warming between 1.4 and 0.9 ka BP, linked to the ‘Medieval Climate Anomaly’; (4) severe cooling of the WGC after 0.9 ka BP, culminating at 0.3 ka BP during the ‘Little Ice Age’. We show that multicentennial-scale palaeoceanography variability along the West Greenland margin is driven by ocean forcing, i.e. variations in the relative contribution of Atlantic (Irminger Current) and Polar (East Greenland Current) water masses to the WGC during the last ~7 ka BP, influencing ice sheet dynamics.

Citation

Perner, K., Moros, M., Jennings, A., Lloyd, J., & Knudsen, K. (2013). Holocene palaeoceanographic evolution off West Greenland. Holocene, 23(3), 374-387. https://doi.org/10.1177/0959683612460785

Journal Article Type Article
Publication Date Mar 1, 2013
Deposit Date Nov 29, 2012
Publicly Available Date Aug 2, 2013
Journal Holocene
Print ISSN 0959-6836
Electronic ISSN 1477-0911
Publisher SAGE Publications
Peer Reviewed Peer Reviewed
Volume 23
Issue 3
Pages 374-387
DOI https://doi.org/10.1177/0959683612460785
Keywords Benthic foraminifera, EGC, Holocene, IC, Ocean forcing, WGC.
Public URL https://durham-repository.worktribe.com/output/1470557

Files






You might also like



Downloadable Citations