On the glacial-interglacial variability of the Asian monsoon in speleothem δ <sup>18</sup> O records
Guangxin Liu, Xianglei Li, Hong‐Wei Chiang, Hai Cheng, Shufang Yuan, Sakonvan Chawchai, Shaoneng He, Yi Lü, Lin Thu Aung, Phyo Maung Maung, W. N. Tun, Kyaw Moe Oo, Xianfeng Wang
Abstract
O records from three locations along the trajectory of the Indian summer monsoon (ISM), a major branch of the AM, and characterize AM rainfall over the past 180,000 years. We have found that the records close to the monsoon moisture source show large glacial-interglacial variability, which then decreases landward. These changes likely reflect a stronger oxygen isotope fractionation associated with progressive rainout of AM moisture during glacial periods, possibly due to a larger temperature gradient and suppressed plant transpiration. We term this effect, which counteracts the forcing of glacial boundary conditions, the moisture transport pathway effect.