青藏高原北部可可西里太阳湖记录的过去200年湿度演化

Moisture Evolution over the Last 200 years Recorded from Lake Taiyang, Northern Qinghai-Xizang Plateau

中文关键词:  青藏高原北部  太阳湖  200年  湿度  NAO

英文关键词:Northern Qinghai-Xizang Plateau  Lake Taiyang  200 years  Moisture  NAO

中文摘要:

      青藏高原对亚洲季风和西风响应敏感,但青藏高原北部的古气候研究较少。本文以青藏高原北部可可西里腹地的太阳湖为研究对象,通过₁₃₇^Cs/₂₁₀^Pb建立过去200年的年代序列,通过X射线荧光光谱(XRF)的高分辨率元素,结合磁化率指标,重建了过去200年太阳湖湖区的干湿变化,并探讨了驱动机制。结果表明,太阳湖湖区小冰期末期气候湿润、现代暖期气候干旱。这一气候特征在青藏高原北部具有区域上的一致性。通过与北大西洋涛动(NAO)指数的对比发现,太阳湖揭示的气候干湿变化分别与NAO指数的正负相位变化具有很好的一致性,表明在过去200年的短时间尺度上,青藏高原北部的气候干湿变化受NAO的控制。

英文摘要:

      The Qinghai-Xizang Plateau is sensitive to the Asian monsoon and westerlies, but the paleoclimate research on the northern Qinghai-Xizang Plateau is currently limited. Lake Taiyang lies in the hinterland of Hoh Xil area, northern Qinghai-Xizang Plateau. In this paper, we use the chronological sequence established by 137Cs/210Pb, as well as elements obtained from high-resolution X-ray fluorescence (XRF) scanning, and magnetic susceptibility, to reconstruct the moisture changes over the last 200 years, and to investigate the driving mechanisms. The results indicate that the Lake Taiyang area experienced a humid climate at the end of the Little Ice Age and an arid climate during the Modern Warm Period. This climatic pattern is generally consistent throughout the northern Qinghai-Xizang Plateau. Furthermore, the arid and humid climate recorded from Lake Taiyang corresponds well to the positive and negative phase of the North Atlantic Oscillation (NAO) index, respectively. This indicates that the moisture changes in the northern Qinghai-Xizang Plateau are influenced by the NAO on short time scales over the past 200 years.