Shut down of the South American summer monsoon during the penultimate glacial

• Published in: Scientific Reports
• Main Authors: Rodríguez-Zorro, Paula, Ledru, Marie-Pierre, Bard, Edouard, Aquino-Alfonso, Olga, Camejo, Adriana, Daniau, Anne-Laure, Favier, Charly, Garcia, Marta, Mineli, Thays, Rostek, Frauke, Ricardi-Branco, Fresia, Sawakuchi, André Oliveira, Simon, Quentin, Tachikawa, K., Thouveny, Nicolas
• Other Authors: Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement IRD : UR226-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD), Collège de France - Chaire Evolution du climat et de l'océan, Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Universidade Estadual de Campinas = University of Campinas (UNICAMP), 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), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Universidade de São Paulo = University of São Paulo (USP), Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)BIOTA 2013/50297-0National Science Foundation (NSF)DEB 1343578Foundation BNP PARIBASCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ)304727/2017-2303527/2017-0
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; [SDE.MCG]Environmental Sciences/Global Changes; Antarctic; Antarc*
• Online Access: https://hal.science/hal-02543791; https://hal.science/hal-02543791/document; https://hal.science/hal-02543791/file/s41598-020-62888-x.pdf; https://doi.org/10.1038/s41598-020-62888-x

International audience We analysed changes in mean annual air temperature (MAAt), vegetation and biomass burning on a long and continuous lake-peat sediment record from the colônia basin, southeastern Brazil, examining the responses of a wet tropical rainforest over the last 180 ka. Stronger southern atmospheric circulation up to the latitude of colônia was found for the penultimate glacial with lower temperatures than during the last glacial, while strengthening of the South American summer monsoon (SASM) circulation started during the last interglacial and progressively enhanced a longer wet summer season from 95 ka until the present. Past MAAT variations and fire history were possibly modulated by eccentricity, although with signatures which differ in average and in amplitude between the last 180 ka. Vegetation responses were driven by the interplay between the SASM and southern circulation linked to Antarctic ice volume, inferred by the presence of a cool mixed evergreen forest from 180 to 45 ka progressively replaced by a rainforest. We report cooler temperatures during the marine isotope stage 3 (MIS 3: 57-29 ka) than during the Last Glacial Maximum (LGM: 23–19 ka). Our findings show that tropical forest dynamics display different patterns than mid-latitude during the last 180 ka.