洋纳朋错记录的青藏高原中部过去2000年降水与大气环流变化

青藏高原中部受亚洲季风与西风环流的共同影响，区域气候变化对于研究中纬度不同环流系统演变至关重要。然而，由于缺少年代可靠、代用指标气候意义明确的高分辨率记录，高原中部过去2000年气候变化及其驱动机制尚不明确。项目拟选择青藏高原中部现代季风边缘区洋纳朋错湖泊沉积为研究对象，通过分析碳酸盐氧同位素、叶蜡单体氢同位素、介形类种属组合等代用指标，结合210Pb、137Cs及AMS14C多种测年手段建立的年代序列，在湖泊水文-气候现代过程研究的基础上，重建研究区过去2000年高分辨率降水变化序列，认识季风、西风环流对区域降水影响的过程与机制。通过与高原不同地点气候记录进行对比，探讨影响青藏高原中部气候变化的驱动机制。研究结果可为深入理解2000年来亚洲季风和西风环流相互作用过程与机制提供科学依据。

The central Tibetan Plateau (TP) is affected by the Asian summer monsoon (ASM) and the westerlies. Therefore, the regional climate variation is determined by the variations of the two circulations. However, the long-term monsoon dynamics are still less well understood in the central TP due to lack of well-dated and high-resolution paleoclimate records, hampering the understanding of the variations of the ASM and the westerlies. Here, we select the Yangnapeng Co as the study site. Two sediment cores will be drilled from the lake and the chronology will be built using 210Pb, 137Cs and AMS14C dates after the reservoir effect was carefully assessed. Multi-proxy (such as carbonate oxygen isotopes, leaf wax hydrogen isotopes, ostracod assemblages, etc.), combined with the detailed studies on modern environmental processes, will be used to reconstruct a high-resolution precipitation variation history and the possible influence of the ASM and the westerlies on regional precipitation during the past 2000 years in the central TP. Reliable records from other parts of the TP are then compared to investigate the similarities and differences of climate change in the TP region and the possible mechanisms. The result of this project can provide the scientific supports for profound understanding the interplay history between the ASM and the westerlies during the past 2000 years in the central TP.