The moisture dynamics in arid Central Asia over the last 47,000 years: Insights from the speleothem record

• 成果类型: Article
• 署名作者: Cai, Yanjun; Cheng, Hai; Breitenbach, Sebastian F. M.; Shukurov, Nosir; Petrov, Maxim; Shukurov, Shukhrat; Lei, Jing; Yang, Yingjie; Xue, Gang; Ma, Le; Huang, Shouyi; Li, Ruoxin; He, Mei; Shi, Zhengguo; Li, Hanying; Ning, Youfeng; Jia, Xuexue; Hao, Yifei; Osinzev, Alexander; Edwards, R. Lawrence; An, Zhisheng
• 署名单位: Xi'an Jiaotong University; Chinese Academy of Sciences; Institute of Earth Environment, CAS; Yunnan Normal University; Northumbria University; University of Minnesota System; University of Minnesota Twin Cities
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.2537342123
• 发表日期: 2026-09-01
• 页码: e2537342123
• 关键词: moisture; DYNAMICS; arid central asia; speleothem; oxygen isotope; HOLOCENE MOISTURE; high-resolution; MONSOON RECORD; north-atlantic; isotopic composition; experimental-design; CLIMATE-CHANGE; cave; precipitation; gisp2

摘要

Water resources are crucial for the survival and development of human societies in arid Central Asia. However, our understanding of regional hydroclimate variability and moisture dynamics remains limited. Here, we present a precisely dated, high-resolution speleothem delta 18O record from caves in northern Uzbekistan that reconstructs changes in precipitation delta 18O over the last 47,000 years. During the glacial interval, relatively low speleothem delta 18O values align with precipitation isotope records from high northern latitudes. The close correspondence between the Uzbekistan record and Greenland ice-core delta 18O during Heinrich Stadial 1 indicates a strong temperature control on regional precipitation delta 18O, although Dansgaard-Oeschger-scale variability is weakly expressed. During the Holocene, speleothem delta 18O reached minimum values near 8 ka BP and then increased toward the present, broadly consistent with records from southern Uzbekistan and the Asian monsoon region, but with less coherent centennial- to millennial-scale variability. Supported by model simulations, we propose that during the glacial and mid-Holocene, when winter temperatures were low, the regional precipitation was dominated by northerly and northwesterly moisture transport linked to enhanced high-latitude temperature gradients and southward-shifted westerlies. In contrast, late Holocene hydroclimate increasingly reflected southerly to southwesterly cyclonic moisture transport from the eastern Mediterranean and the Near East, driven by northward-shifted westerlies. These results show that arid Central Asian hydroclimate and precipitation delta 18O have been shaped by the position and strength of the westerlies through major reorganizations in moisture-source trajectories, with direct implications for understanding future water availability as subtropical and temperate circulation zones shift northward.