7.5~7.0 cal.ka B.P.气候事件在中国地区的表现及其动力机制

识别全新世气候事件、阐明其区域环境表现特征、揭示其驱动机制是理解气候系统变化行为、预测未来气候变化以及弄清考古学文化转变动因的关键，具有重要的科学价值和现实意义。随着高分辨率全新世古气候重建的进展，7.5~7.0 cal.ka B. P.事件逐渐被揭示，但到目前为止仍缺乏针对该气候事件各种类型证据的系统收集、对比以及对其产生动力机制的分析。本文基于中国26条古气候记录，系统总结了这一气候事件在中国地区的环境表现。结果显示，7.5~7.0 cal.ka B. P.气候事件在中国多个地区都有明显的反映，整体表现为温度下降、夏季风强度减弱。与全球其他地区的古气候记录对比显示7.5~7.0 cal.ka B. P.气候事件可能具有全球性的特征。与驱动因子系列对比发现该气候事件发生在北半球夏季太阳辐射逐渐减少、太阳活动减弱、火山活动频发、劳伦泰德冰盖快速融化期间，表明这4种因素在7.5~7.0 cal.ka B. P.气候事件发生过程中发挥了作用。未来需要更多测年准确、分辨率高的古气候记录定量-半定量刻画该气候事件的变化幅度、起止时间以及区域差异，同时结合古气候模拟揭示7.5~7.0 cal.ka B. P.气候事件产生的动力机制。

Environmental expressions of 7.5~7.0 cal. ka B.P. climate event in China and its dynamic mechanisms

Identification of Holocene climate events and their regional environmental expressions, exploration of their temporal and spatial characteristics, and investigation of the dynamic mechanisms behind them are important for understanding climate system, forecasting future climate changes and interpreting the cultural transformations. With the advances in Holocene paleoclimate reconstructions, one climate event at 7.5~7.0 cal. ka B.P. is increasingly recognized but lack a systematic review. In this paper, we review paleoclimate evidences from 26 sites covering most of China to detect 7.5~7.0 cal.ka B.P. climate event, including 24 well-dated and highly-resolved paleoclimate time series together with 2 lower-quality paleoclimate records.