Equatorial heat accumulation as a long-term trigger of permanent Antarctic ice sheets during the Cenozoic

• Published in: Proceedings of the National Academy of Sciences
• Main Authors: Tremblin, Maxime, Hermoso, Michaël, Minoletti, Fabrice
• Other Authors: Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences Oxford, University of Oxford
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology; Antarctic; Austral; Antarc*; Antarctica
• Online Access: https://hal.science/hal-01376097; https://hal.science/hal-01376097/document; https://hal.science/hal-01376097/file/Tremblin_2016_Equatorial_heat.pdf; https://doi.org/10.1073/pnas.1608100113

International audience The long-term cooling trend of the Cenozoic is punctuated by shorter-term climatic events, such as the inception of permanent ice sheets on Antarctica at the Eocene−Oligocene Transition (∼33.7 Ma). Taking advantage of the excellent state of preservation of coccolith calcite in equatorial Atlantic deep-sea cores, we unveil progressive tropical warming in the Atlantic Ocean initiated 4 million years prior to Antarctic glaciation. Warming preceding glaciation may appear counterintuitive, but we argue that this long-term climatic precursor to the EOT reinforced cooling of austral high latitudes via the redistribution of heat at the surface of the oceans. We discuss this new prominent paleoceanographic and climatic feature in the context of overarching pCO2 decline and the establishment of an Antarctic circumpolar current.