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基于辽宁省暖和洞2支石笋6个230Th年龄与190个δ18O数据,建立了晚全新世3500～200a B.P.东亚季风降水序列。3个百年尺度的弱季风事件已被证实:2800-2600、1500-1200和400-200a B.P.,其与北大西洋冰漂碎屑事件在发生时间上具有较好的一致性。与内陆高精度、高分辨率石笋δ18O记录对比结果显示:1)轨道-千年尺度季风降水长期趋势变化相一致;2)百年-数十年尺度上季风降水具有明显的区域性,如距今1200-500 a B.P.,东北地区降水逐渐增加,西部干旱-半干旱地区降水逐渐减少,长江中下游以及南方地区降水变化趋势不明显。太阳活动与北大西洋气候波动可能对百年尺度东亚夏季风的强弱变化施加了重要影响。
Based on 6 230Th ages and 190 δ18O data of two stalagmites from the Hehualuo Cave in Liaoning Province, a series of B.P. East Asian monsoon precipitation sequences from the late Holocene 3500 ~ 200a were established. Three hundred-year-scale weak monsoon events have been demonstrated: 2800-2600, 1500-1200 and 400-200a B.P., which are in good agreement with the North Atlantic ice drift debris event. Compared with the δ18O records of inland high-resolution and high-resolution stalagmite, the results show that: 1) the long-term trend of orbital-millennial monsoon precipitation is consistent; 2) Centennial-Monsoon precipitation has significant regional characteristics on the scale of decades, 1200-500 a BP. Precipitation in northeast China gradually increased. Precipitation in the arid and semi-arid regions of western China gradually decreased while precipitation in the middle and lower reaches of the Yangtze River and the south of China did not change significantly. Solar activity and the North Atlantic climatic fluctuations may exert a significant influence on the intensity of the East Asian summer monsoon over the centuries.