Dinocyst-derived sea-surface characteristics, palynomorph abundances, ice-rafted debris, and planktonic foraminifera abundances and δ¹⁸O of the 35-41 ka BP interval of core MD99-2285, supplement to: Wary, Mélanie; Eynaud, Frédérique; Rossignol, Linda; Lapuyade, Joanna; Gasparotto, Marie-Camille; Londeix, Laurent; Malaizé, Bruno; Castera, Marie-Hélène; Charlier, Karine (2016): Norwegian Sea warm pulses during Dansgaard-Oeschger stadials: Zooming in on these anomalies over the 35–41 ka cal BP interval and their impacts on proximal European ice-sheet dynamics. Quaternary Science Reviews, 151, 255-272

• Main Authors: Wary, Mélanie, Eynaud, Frédérique, Rossignol, Linda, Lapuyade, Joanna, Gasparotto, Marie-Camille, Londeix, Laurent, Malaizé, Bruno, Castera, Marie-Hélène, Charlier, Karine
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2016
• Subjects: DEPTH, sediment/rock; AGE; Dinoflagellate cyst reworked per volume; Pediastrum spp., coenobia; Halodinium spp.; Bitectatodinium tepikiense; Operculodinium centrocarpum; Islandinium minutum var. minutum; Diversity; Dominance; Sea surface temperature, winter; Sea surface temperature, summer; Sea ice cover duration; Sea surface salinity, winter; Sea surface salinity, summer; Primary production of carbon; Neogloboquadrina pachyderma sinistral, δ18O; Neogloboquadrina pachyderma sinistral; Foraminifera, planktic; Ice rafted debris; Calypso Corer; MD114; Marion Dufresne 1995; Norwegian Sea; Greenland; Hélène; Ice Sheet; Neogloboquadrina pachyderma; Planktonic foraminifera; Sea ice
• Online Access: https://dx.doi.org/10.1594/pangaea.864808; https://doi.pangaea.de/10.1594/PANGAEA.864808

The last glacial millennial climatic events (i.e. Dansgaard-Oeschger and Heinrich events) constitute outstanding case studies of coupled atmosphere-ocean-cryosphere interactions. Here, we investigate the evolution of sea-surface and subsurface conditions, in terms of temperature, salinity and sea ice cover, at very high-resolution (mean resolution between 55 and 155 years depending on proxies) during the 35-41 ka cal BP interval covering three Dansgaard-Oeschger cycles and including Heinrich event 4, in a new unpublished marine record, i.e. the MD99-2285 core (62.69°N; -3.57°E). We use a large panel of complementary tools, which notably includes dinocyst-derived sea-ice cover duration quantifications. The high temporal resolution and multiproxy approach of this work allows us to identify the sequence of processes and to assess ocean-cryosphere interactions occurring during these periodic ice-sheet collapse events. Our results evidence a paradoxical hydrological scheme where (i) Greenland interstadials are marked by a homogeneous and cold upper water column, with intensive winter sea ice formation and summer sea ice melting, and (ii) Greenland and Heinrich stadials are characterized by a very warm and low saline surface layer with iceberg calving and reduced sea ice formation, separated by a strong halocline from a less warm and saltier subsurface layer. Our work also suggests that this stadial surface/subsurface warming started before massive iceberg release, in relation with warm Atlantic water advection. These findings thus support the theory that upper ocean warming might have triggered European ice-sheet destabilization. Besides, previous paleoceanographic studies conducted along the Atlantic inflow pathways close to the edge of European ice-sheets suggest that such a feature might have occurred in this whole area. Nonetheless, additional high resolution paleoreconstructions are required to confirm such a regional scheme.