Paleoclimate of Southwest China: Development of the Asian Monsoon

ATM-9305750 Brenner，标记标题：西南古气候中国：亚洲季风的发展本奖项支持对云南四个湖泊沉积岩心的研究，以恢复晚更新世至今的中国西南古气候。获得了较长的14C测年剖面(10kyr BP)。与大气环流模型的“预测”相反，花粉、硅藻和地球化学数据表明，从晚更新世潮湿的环境转变为更干燥的全新世早期。沉积物记录还表明，在全新世期间，湖泊水位发生了变化。近距离采样和AMS测年将提高古气候记录的年代学分辨率。沉积的介形类贝壳中稳定的同位素和痕量金属比率将被用来检验以前的古气候推断，并确定晚更新世高湖面是否是冰川融水输入的结果。古环境重建也将基于碳酸盐和有机质中稳定的同位素信号。中国西南地区的替代古气候资料将揭示亚洲季风系统的发展，并可用于检验大气环流模式的湿度模拟。

Abstract ATM-9305750 Brenner, Mark Title: Paleoclimate of Southwest China: Development of the Asian Monsoon This award suports a study of sediment cores from four Yunnan lakes which will be used to reconstruct the paleoclimate of southwest China from late Pleistocene to present . Long, 14C-dated sections (10kyr BP) have been obtained. Contrary to "predictions" from general circulation models, pollen, diatom and geochemical data indicate a shift from wet late Pleistocene to drier early Holocene conditions. The sediment record also suggests lake-level shifts during the Holocene. Chronologic resolution of paleoclimatic records will be enhanced by close-interval sampling and AMS dating. Stable isotope and trace metal ratios in sedimented ostracod shells will be used to test previous paleoclimatic inferences and establish whether late-Pleistocene, high lake levels were a consequences of glacial meltwater input. Paleoenvironmental reconstruction will also be based on stable isotope signals in carbonates and organic matter. Proxy paleoclimatic data from southwest China will shed light on the development of the Asian monsoon system and can be used to test moisture simulations from general circulation models.