摘要
12个U/Th年龄测试结果显示,黔西南普安县雾露洞长度分别为667mm和830mm的两支石笋覆盖了61～50kaBP时段。据两支石笋999个δ18O数据建立了平均分辨率达15年的亚洲夏季风强度变化序列。雾露洞δ18O记录揭示了4个振幅达1.7‰的千年尺度季风增强事件,对应于格陵兰冰心DO17—DO14事件。在总体特征上,该记录峰谷振荡特征及振幅与贵州董歌洞、南京葫芦洞记录一致,进一步证实亚洲季风区大气降水同位素组成变化在大范围空间内具有一致性。在百年尺度上,亚洲季风区石笋δ18O清晰记录了MIS3早期6个DO亚旋回事件,而且在更短时间尺度上具有类似高纬气温振荡特征。这种低纬季风系统与北高纬气候变化的耦合关系表明,大气环流快速重组和传输可能是连接高低纬DO旋回及亚旋回气候变化的主要纽带。
An 15-year resolution oxygen-isotope profile, based on 12 230Th dates and 999 9180 data from two stalagmites （Wu23,Wu26） from Wulu Cave of southwest of Guizhou Province, China, provides a detailed history of the Asian monsoon variability between 61 and 51 kaBP. During this time interval, four cycles of millennial variations in δ18O values, averaging 1.7‰,are consistent with Dansgaard-Oeschger 17-14 events identified in the Greenland ice cores. A comparison between the Wulu, Hulu and Dongge Cave records dis- plays a generally similar pattern of δ18O variability between the three sites, indicating an inherently homogenous trait of Asian monsoon precipitation. Our data strikingly match well with those from the Greenland ice cores on centennial time scales, including the sub-cycles for these D-O events. The rapid monsoon cir- culation fluctuations during these sub-millennial events parallel the sharp jumps in high north-latitude temperatures. This relationship provides strong evidences for an impact of rapid atmosphere reorganization on the NH climate changes, which links different climate systems between low- and high-latitudes. The relat- ed changes in the atmosphere field possibly result in the co-variations between low-latitude monsoon sys- tem and the high north-latitude climate system on centennial time scales.
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
2008年第5期85-92,共8页
Marine Geology & Quaternary Geology
基金
国家自然科学基金项目(40771009)
关键词
DO亚旋回
MIS3
石笋
雾露洞
Dansgaard-Oeschger sub-cycles
Marine Isotope Stage 3
stalagmite
Wulu Cave
