LGP UMR 8591 CNRS Paris 1 Panthéon-Sorbonne University CNRS, 92195, Meudon, France.
Aix-Marseille University, CNRS, IRD, Coll. France, INRAE, CEREGE, 13545, Aix-en-Provence, France.
Nat Commun. 2022 Mar 17;13(1):1419. doi: 10.1038/s41467-022-28939-9.
Based on new and published cosmic-ray exposure chronologies, we show that glacier extent in the tropical Andes and the north Atlantic regions (TANAR) varied in-phase on millennial timescales during the Holocene, distinct from other regions. Glaciers experienced an early Holocene maximum extent, followed by a strong mid-Holocene retreat and a re-advance in the late Holocene. We further explore the potential forcing of TANAR glacier variations using transient climate simulations. Since the Atlantic Meridional Overturning Circulation (AMOC) evolution is poorly represented in these transient simulations, we develop a semi-empirical model to estimate the "AMOC-corrected" temperature and precipitation footprint at regional scales. We show that variations in the AMOC strength during the Holocene are consistent with the observed glacier changes. Our findings highlight the need to better constrain past AMOC behavior, as it may be an important driver of TANAR glacier variations during the Holocene, superimposed on other forcing mechanisms.
基于新的和已发表的宇宙射线暴露年代学，我们表明，在全新世，热带安第斯山脉和北大西洋地区（TANAR）的冰川范围在千年时间尺度上呈同相变化，与其他地区明显不同。冰川经历了全新世早期的最大范围，随后是强烈的全新世中期退缩和全新世晚期的再次推进。我们进一步利用瞬态气候模拟探讨了 TANAR 冰川变化的潜在驱动力。由于这些瞬态模拟中对大西洋经向翻转环流（AMOC）的演变描述不佳，我们开发了一个半经验模型来估计区域尺度上的“AMOC 校正”温度和降水足迹。我们表明，全新世期间 AMOC 强度的变化与观察到的冰川变化一致。我们的研究结果强调需要更好地约束过去 AMOC 的行为，因为它可能是全新世 TANAR 冰川变化的重要驱动因素，叠加在其他驱动机制之上。
