Mechanisms of Global Ocean Ventilation Age Change during the Last Deglaciation

• DOI: 10.5194/egusphere-2023-2256
• Publication Date: 2023-10-09T12:16:20Z
• Authors: Lingwei Li; Zhengyu Liu; Jinbo Du; Lingfeng Wan; Jiuyou Lu
• Keywords: Deglaciation; Last Glacial Maximum; Antarctic Bottom Water; Post-glacial rebound

Abstract. Marine radiocarbon (14C) is widely used to trace deep ocean circulation, providing insight into the atmosphere-ocean exchange of CO2 during last deglaciation. Using two transient simulations with tracers 14C and ideal age, we found that oldest ventilation age not observed at Last Glacial Maximum (LGM). In contrast, model shows a modestly younger LGM compared present day, mainly due stronger glacial Antarctic Bottom Water (AABW) transport associated sea ice expansion. Notably, significantly older around 14–12 ka LGM, Pacific waters playing predominant role, primarily caused by weakening AABW transport.