Low COâ‚‚ levels of the entire Pleistocene epoch

• Published in: Nature Communications
• Main Authors: Da, Jiawei, Zhang, Yi Ge, Li, Gen, Meng, Xianqiang, Ji, Junfeng
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Nature Publishing Group 2019
• Subjects: ice core
• Online Access: https://doi.org/10.1038/s41467-019-12357-5; https://www.ncbi.nlm.nih.gov/pmc/PMC6761161

Quantifying ancient atmospheric pCO₂ provides valuable insights into the interplay between greenhouse gases and global climate. Beyond the 800-ky history uncovered by ice cores, discrepancies in both the trend and magnitude of pCO₂ changes remain among different proxy-derived results. The traditional paleosol pCO₂ paleobarometer suffers from largely unconstrained soil-respired CO₂ concentration (S(z)). Using finely disseminated carbonates precipitated in paleosols from the Chinese Loess Plateau, here we identified that their S(z) can be quantitatively constrained by soil magnetic susceptibility. Based on this approach, we reconstructed pCO₂ during 2.6–0.9 Ma, which documents overall low pCO₂ levels (<300 ppm) comparable with ice core records, indicating that the Earth system has operated under late Pleistocene pCO₂ levels for an extended period. The pCO₂ levels do not show statistically significant differences across the mid-Pleistocene Transition (ca. 1.2–0.8 Ma), suggesting that CO₂ is probably not the driver of this important climate change event. © 2019 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Received 08 January 2019; Accepted 05 September 2019; Published 25 September 2019. ...