Presence of the solar de Vries cycle (~205 years) during the last ice age

• Published in: Geophysical Research Letters
• Main Authors: Wagner, Gerhard, Beer, Jürg, Masarik, Jozef, Muscheler, Raimund, Kubik, Peter, W., Mende, Werner, Laj, Carlo, Raisbeck, Grant, M., Yiou, Françoise
• Other Authors: Swiss Federal Insitute of Aquatic Science and Technology Dübendorf (EAWAG), Paul Scherrer Institute (PSI), Freie Universität Berlin, Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Climat et Magnétisme (CLIMAG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), This work was supported by the Swiss National Science Foundation.
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2001
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; ice core
• Online Access: https://hal.in2p3.fr/in2p3-00008529; https://hal.in2p3.fr/in2p3-00008529/document; https://hal.in2p3.fr/in2p3-00008529/file/2000GL006116.pdf; https://doi.org/10.1029/2000GL006116

Certain characteristic periodicities inthe $\Delta ^{14}$C record from tree rings, such as the well-known 11-yr Schwabe cycle, are known to be of solar origin. The origin of longerperiod cycles, such as the 205-yr de Vries cycle, in the $\Delta ^{14}$C record was less certain, and it was possible to attribute it either to solar or climatic variability. Here, we demonstrate that the de Vries cycle is present in $^{10}$Be data from the GRIP ice core during the last ice age (25 to 50 kyr BP). Analysis of the amplitude of variation of this cycle shows it to be modulated by the geomagnetic field, indicating that the de Vries cycle is indeed of solar, rather than climatic, origin.