Rapid changes in surface and deep water conditions at the Faeroe Margin during the last 58,000 years

• Published in: Paleoceanography
• Main Authors: Rasmussen, Tine, Thomsen, Erik, van Weering, Tjeerd, Labeyrie, Laurent
• Other Authors: Geological Institute Copenhagen, University of Copenhagen = Københavns Universitet (UCPH), Department of Earth Sciences Aarhus, Aarhus University Aarhus, Royal Netherlands Institute for Sea Research (NIOZ), Centre des Faibles Radioactivités, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 1996
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Greenland; Norwegian Sea; Greenland ice cores; NADW; North Atlantic Deep Water; North Atlantic
• Online Access: https://hal.archives-ouvertes.fr/hal-03604490; https://hal.archives-ouvertes.fr/hal-03604490/document; https://hal.archives-ouvertes.fr/hal-03604490/file/Paleoceanography%20-%201996%20-%20Rasmussen%20-%20Rapid%20changes%20in%20surface%20and%20deep%20water%20conditions%20at%20the%20Faeroe%20Margin%20during%20the.pdf; https://doi.org/10.1029/96PA02618

International audience A high-resolution piston core, ENAM93-21, from a water depth of 1020 m near the Faeroe-Shetland Channel is investigated for variations in magnetic susceptibility, surface oxygen isotopes, grain size distribution, content of ice-rafted detritus (IRD), and distribution of planktonic and benthic foraminifera. The core, coveting the last 58,000 years, is correlated with the Greenland ice cores and compared with paleorecords from the Norwegian Sea and the North Atlantic Ocean. All fifteen Dansgaard-Oeschger climatic cycles recognized from the investigated time period in the Greenland ice cores have been identified in the ENAM93-21 core. Each cycle is subdivided into three intervals on the basis of characteristic benthic and planktonic faunas. Interstadial intervals contain a relatively warm planktonic fauna and a benthic fauna similar to the modem fauna in the Norwegian Sea. This indicates thermohaline convection as at present, with a significant contribution of deep water to the North Atlantic Deep Water (NADW). Transitional cooling intervals are characterized by more cold water planktonic foraminfera and ice-related benthic species. The benthic fauna signifies restricted bottom water conditions and a reduced contribution to the NADW. The peak abundance of N. pachyderma (s.) and the coldest surface water conditions are found in the stadial intervals. The benthic fauna is dominated by species with an association to Atlantic Intermediate Water, suggesting an increased Atlantic influence in the Norwegian Sea, and there was probably no contribution to the NADW through the Faeroe-Shetland Channel. The three different modes of circulation can be correlated to paleoceanographic events in the Norwegian Sea and the North Atlantic Ocean.