Variations of the ACC-CDW during MIS3 traced by magnetic grain deposition in midlatitude South Indian Ocean cores: Connections with the northern hemisphere and with central Antarctica

• Published in: Geochemistry, Geophysics, Geosystems
• Main Authors: Mazaud, A., Kissel, C., Laj, C., Sicre, M., Michel, E., Turon, J.L.
• Other Authors: Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Climat et Magnétisme (CLIMAG), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2007
• Subjects: Components: 4603 words; 11 figures; 1 table Keywords: paleoceanography; south; Indian; ocean Index Terms: 0473 Biogeosciences: Paleoclimatology and paleoceanography (3344; 4900); 1512 Geomagnetism and Paleomagnetism: Environmental magnetism; 4938 Paleoceanography: Interhemispheric phasing; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Antarctic; Byrd; Greenland; Kerguelen; The Antarctic; Antarc*; Antarctica; North Atlantic Deep Water; North Atlantic
• Online Access: https://hal.archives-ouvertes.fr/hal-02913507; https://hal.archives-ouvertes.fr/hal-02913507/document; https://hal.archives-ouvertes.fr/hal-02913507/file/2006GC001532.pdf; https://doi.org/10.1029/2006GC001532

International audience [1] We examine the magnetic mineral deposition in three cores located at midlatitude sites in the South Indian Ocean, in an area where sediment eroded from the Kerguelen-Crozet plateau and transported by the marine currents, principally the Antarctic Circum Current, accumulates at a high sedimentation rate. We focus on Marine Isotopic Stage 3, characterized by large climatic fluctuations at northern latitudes, and compare the obtained records to the climatic records at Byrd (Antarctica) and Summit (GISP2, Greenland) and to the North Atlantic Deep Water variations in the North Atlantic. Magnetic mineral deposition at the studied sites exhibits a profile with maxima at the time of Heinrich events H4 and H5, which suggests a strong Antarctic Circum Current when the North Atlantic Deep Water was reduced at northern latitude during these events. We show that an interhemispheric seesaw, characterized by temporary surface warmings in the southern hemisphere, is also marked by a strong Antarctic Circum Current at the time of the northern Heinrich events. The rapid Dansgaard-Oeschger oscillations evidenced in the northern records after interstadials IS12 and IS8 are not visible, suggesting a limited counterpart of these events in the midlatitude southern Indian Ocean.