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位于青藏高原与黄土高原过渡带的甘肃武都万象洞石笋WXSM51和WXSM52提供了M IS 5(118~79kaB.P.)高分辨率的1δ8O记录。研究表明,万象洞石笋1δ8O值与夏季风强度呈负相关关系,与我国西南部的贵州董歌洞石笋1δ8O记录有良好的对应关系,并与高纬度的格陵兰NGR IP冰芯1δ8O记录和65°N太阳辐射强度有很好的一致性,说明万象洞石笋1δ8O记录了118~79kaB.P.期间亚洲季风强度的变化,同时也说明东亚季风强度的变化和全球气候变化同步,而且主要受控于北半球太阳辐射强度的变化。同时它与地中海碳酸盐记录有很好的相似性,和巴西石笋1δ8O记录在千年尺度上表现出相反的变化趋势,说明东亚季风区、地中海地区以及巴西季风区之间存在密切的联系,指示了南北半球气候在千年尺度上存在“跷跷板”(seesaw)现象。万象洞石笋1δ8O记录的M IS 5b与M IS 5 a突发性转换,与NGR IP冰芯1δ8O记录相似,而与神农架记录存在差异,说明万象洞地区对亚洲季风强度的响应更为敏感。
The stalagmite WXSM51 and WXSM52 in Vientiane Cave, Gansu, located in the transition zone between the Qinghai-Tibet Plateau and the Loess Plateau, provide 1δ8O records with M IS 5 (118-79 kaB.P.) high resolution. The results show that there is a negative correlation between 1δ8O value of stalagmite and summer monsoon intensity in Vientiane. It has a good correspondence with 1δ8O record of stalagmite from Dongge Cave in Guizhou province in southwestern China, and is consistent with 1δ8O records of high latitude NGR IP ice core and 65 ° N solar radiation intensity shows a good consistency, indicating Vientiane Cave stalagmite 1δ8O recorded 118 ~ 79kaB.P. Asian monsoon intensity changes, but also shows that the East Asian monsoon intensity changes and global climate change synchronization, and is mainly controlled by Changes in solar radiation intensity in the northern hemisphere. At the same time, it has a good similarity with the Mediterranean carbonate records, and the records of the stalagmite 1δ8O in Brazil show the opposite trend on the millennium scale. This indicates that there is a close relationship between the East Asian monsoon region, the Mediterranean region and the Brazilian monsoon region. The “seesaw” phenomenon exists on the millennium scale in the northern and southern hemispheric climate. The sudden transition of M IS 5b and M IS 5 a recorded by stalagmite 1δ8O in Vientiane cave is similar to that recorded in NGR IP ice core 1δ8O record but differs from that recorded in Shennongjia, indicating that the Vientiane-dong region is more sensitive to the Asian monsoon intensity.