On the origin of the 100-kyr cycle in the astronomical forcing

• Published in: Paleoceanography
• Main Authors: Berger, André, Loutre, Marie-France, Mélice, Jean-Luc
• Other Authors: Institut d'Astronomie et de Géophysique Georges Lemaître (UCL-ASTR), Université Catholique de Louvain = Catholic University of Louvain (UCL), Oceanography Department (UCT-OD), University of Cape Town, Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-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)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2005
• Subjects: [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph]; [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph]; Antarc*; Antarctica; ice core
• Online Access: https://hal.science/hal-00122845; https://hal.science/hal-00122845/document; https://hal.science/hal-00122845/file/2005PA001173.pdf; https://doi.org/10.1029/2005PA001173

Investigations during the last 25 years have demonstrated that the astronomically related 19-, 23-, and 41-kyr quasiperiodicities actually occur in long records of the Quaternary climate. However, the same investigations also identified the largest climatic cycle as being about 100 kyr long. As the 100-kyr variations in standing insolation due to eccentricity change are too small, they cannot be the direct cause of the ice ages. This is the reason why most of the modeling studies attempting to explain the relation between the astronomical forcing and climatic change have focused on this 100-kyr cycle. In this paper, we will show the astronomical origin of the periods at about 100 kyr that characterize the long-term variations of eccentricity, of its first derivative, of the frequency modulation of obliquity, and of the inclination of the Earth's orbit on the invariable plane of reference. Five independent values are found between 95 and 107 kyr, and a wavelet signature is suggested to test the possible relationships between the astronomical and climatic variables. Proxy records from deep-sea cores and European Programme for Ice Coring in Antarctica ice core and modeling results from the Louvain-la-Neuve two-dimensional model are used for illustration.