Could deep subantarctic convection feed the world deep basins during the Last Glacial Maximum?

• Published in: Paleoceanography
• Main Authors: Michel, Elisabeth, Labeyrie, Laurent, Duplessy, Jean-Claude, Gorfti, Nabila, Labracherie, Monique, Turon, Jean-Louis
• Other Authors: Centre des Faibles Radioactivités, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Environnements et Paléoenvironnements OCéaniques (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-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 1995
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Pacific; Southern Ocean; North Atlantic
• Online Access: https://hal.science/hal-02913417; https://hal.science/hal-02913417/document; https://hal.science/hal-02913417/file/ark%20_67375_WNG-DR09514G-H.pdf; https://doi.org/10.1029/95PA00978

International audience Simple box model calculations are used to simulate the oceanic circulation during the last glacial maximum (LGM). These experiments show that the main features of the 1513C and A14C distributions and of the lysocline depth may be explained by a circulation pattern very different from the modem one. Intermediate and upper deep waters were produced in the North Atlantic Ocean, whereas deep waters of Subantarctic Mode type, forming at the northern edge of the Subantarctic convergence, invaded the main oceanic basins. The Southern Ocean, mainly self ventilated, had a reduced deep component that flew southward along the East Pacific Ridge and the Australian west cost. The thermodynamic fractionation that occurs during air-sea exchange has only contributed slightly to the glacial deep 1513C distribution through surface water temperature variations.