Millennial variability of terrigenous transport to the central-southern Peruvian margin during the last deglaciation (18-13 kyr BP)

• Published in: Climate of the Past
• Main Authors: Yseki, Marco, Turcq, Bruno, Caquineau, Sandrine, Salvatteci, Renato, Solis, José, Skilbeck, C. Gregory, Velazco, Federico, Gutiérrez, Dimitri
• Other Authors: Variabilité à long terme du climat de l'océan (VALCO), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Christian-Albrechts-Universität zu Kiel = Christian-Albrechts University of Kiel = Université Christian-Albrechts de Kiel (CAU), Universidad Peruana Cayetano Heredia (UPCH), University of Technology Sydney (UTS), Instituto del Mar del Peru (IMARPE), ANR-15-JCLI-0003,PACMEDY,PAlaeo-Constraints on Monsoon Evolution and Dynamics(2015)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2022
• Subjects: [SDU]Sciences of the Universe [physics]; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; North Atlantic
• Online Access: https://insu.hal.science/insu-03846484; https://insu.hal.science/insu-03846484/document; https://insu.hal.science/insu-03846484/file/cp-18-2255-2022.pdf; https://doi.org/10.5194/cp-18-2255-2022

International audience Reconstructing precipitation and wind from the geological record could help researchers understand the potential changes in precipitation and wind dynamics in response to climate change in Peru. The last deglaciation offers natural experimental conditions to test the response of precipitation and wind dynamics to high-latitude forcing. While considerable research has been done to reconstruct precipitation variability during the last deglaciation in the Atlantic sector of South America, the Pacific sector of South America has received little attention. This work aims to fill this gap by reconstructing types of terrigenous transport to the central-southern Peruvian margin (12 and 14° S) during the last deglaciation (18-13 kyr BP). For this purpose, we used grain-size distribution in sediments of marine core M77/2-005-3 (Callao, 12° S) and core G14 (Pisco, 14° S). We analyzed end-members (EMs) to identify grain-size components and reconstruct potential sources and transport processes of terrigenous material across time. We identified four end-members for both Callao and Pisco sediments. In Callao, we propose that the changes in the contributions of EM4 (101 μm) and EM2 (58 μm) mainly reflect the hydrodynamic energy and diffuse sources, respectively, while the variations in EM3 (77 μm) and EM1 (11 μm) reflect changes in the eolian and fluvial inputs, respectively. In Pisco, where there are strong winds and an extensive coastal desert, changes in the contribution of EM1 (10 μm) reflect changes in river inputs, while EM2 (52 μm), EM3 (75 μm), and EM4 (94 μm) reflect an eolian origin. At millennial scale, our record shows an increase in the fluvial inputs during the last part of Heinrich Stadial 1 (∼16-14.7 kyr BP) at both locations. This increase was linked to higher precipitation in the Andes related to a reduction of the Atlantic Meridional Overturning Circulation and meltwater discharge in the North Atlantic. In contrast, during the Bølling-Allerød interstadial (∼14.7-13 kyr BP), there was ...