Holocene water mass changes in the Labrador Current.

Lochte, Annalena Antonia, Repschläger, Janne, Seidenkrantz, Marit-Solveig, Kienast, Markus , Blanz, Thomas and Schneider, Ralph R. (2019) Holocene water mass changes in the Labrador Current. The Holocene, 29 (4). pp. 676-690. DOI 10.1177/0959683618824752.

[img] Text
Supplementary_Information.docx - Supplemental Material

Download (425Kb)
[img] Text
Lochte et.al.pdf - Accepted Version
Restricted to Registered users only

Download (3862Kb)

Supplementary data:

Abstract

The Labrador Current is part of the anticlockwise subpolar gyre and plays a major role in the formation of North Atlantic Deep Water. It is influenced by the West Greenland and Baffin currents supplying warmer Atlantic and cold polar waters, respectively. During the early Holocene, at the final stage of the last deglaciation, meltwater and iceberg discharge caused highly variable conditions in the Labrador Current. In order to assess its sensitivity to such freshening, this study provides a well-resolved Holocene paleoclimatic record from the Labrador Shelf. Based on benthic foraminiferal faunal and alkenone biomarker analyses, we differentiated four distinct climatic periods in the western Labrador Sea. From 8.9 to 8.6 ka BP, the Labrador Shelf was dominated by polar water outflow from Baffin Bay and covered by perennial sea ice. Between 8.6 and 7.4 ka BP, a strong subsurface inflow of warmer Atlantic water masses is ascribed to an intensification and redirection of the West Greenland Current. At 7.4 ka BP, the decreased influence of Atlantic water masses on the Labrador Shelf marks the establishment of winter convection leading to the formation of Labrador Sea Water in the central basin. Concurrently, an intensified polar water outflow through the Canadian Gateways strengthened the inner Labrador Current, and higher primary productivity suggests longer spring blooms because of a shorter sea-ice season during the Holocene Thermal Maximum. In the late Holocene after 3 ka BP, periodic fluctuations of primary productivity may tentatively be correlated with stronger and weaker northwesterly winds.

Document Type: Article
Keywords: alkenones, benthic foraminifera, Holocene, Labrador Current, Labrador Sea, primary productivity, West Greenland Current
Research affiliation: OceanRep > GEOMAR > FB1 Ocean Circulation and Climate Dynamics > FB1-P-OZ Paleo-Oceanography
Kiel University
Refereed: Yes
Open Access Journal?: No
DOI etc.: 10.1177/0959683618824752
ISSN: 0959-6836
Projects: HOSST
Expeditions/Models/Experiments:
Date Deposited: 14 Feb 2019 10:34
Last Modified: 16 Apr 2019 13:18
URI: http://oceanrep.geomar.de/id/eprint/45800

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...