Climate change on the Tibetan Plateau in response to shifting atmospheric circulation since the LGM.
Climate change on the Tibetan Plateau in response to shifting atmospheric circulation since the LGM.
复制标题
末次盛冰期以来青藏高原气候变化对大气环流变化的响应
DOI：
10.1038/srep13318
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发表时间：
2015-08-21
影响因子：
4.6
通讯作者：
Mäusbacher R
中科院分区：
文献类型：
--
作者：
Zhu L;Lü X;Wang J;Peng P;Kasper T;Daut G;Haberzettl T;Frenzel P;Li Q;Yang R;Schwalb A;Mäusbacher R
青藏高原主要受北半球中纬度西风带和印度夏季风的影响。这两个大气环流的范围、远距离影响和潜在的长期变化尚不完全清楚。在这里，我们分析了在西风带和ISM季节交替的过渡带中的现代空气中的花粉，以开发一个花粉辨别指数(PDI)，使我们能够区分这两个循环系统的强度。这一指数被应用于解释过去24 的纳木错湖的连续湖泊沉积记录，称为 KYR BP，以研究大气环流系统的长期变化。青藏高原中部的气候变化与北大西洋(NA)的气候变化基本一致，但受末次冰盛期(LGM)以来气候条件变化的不同机制控制。在LGM期间，直到16.5 Call Kyr BP，TP都是由西风带主导的。16.5 CAL KYR BP后，气候条件主要受ISM控制。从11.6 到9 Call KYR BP，TP暴露在低纬度地区的太阳辐射增强，导致更大的水可获得性。
The Tibetan Plateau (TP) is primarily influenced by the northern hemispheric middle latitude Westerlies and the Indian summer monsoon (ISM). The extent, long-distance effects and potential long-term changes of these two atmospheric circulations are not yet fully understood. Here, we analyse modern airborne pollen in a transition zone of seasonally alternating dominance of the Westerlies and the ISM to develop a pollen discrimination index (PDI) that allows us to distinguish between the intensities of the two circulation systems. This index is applied to interpret a continuous lacustrine sedimentary record from Lake Nam Co covering the past 24 cal kyr BP to investigate long-term variations in the atmospheric circulation systems. Climatic variations on the central TP widely correspond to those of the North Atlantic (NA) realm, but are controlled through different mechanisms resulting from the changing climatic conditions since the Last Glacial Maximum (LGM). During the LGM, until 16.5 cal kyr BP, the TP was dominated by the Westerlies. After 16.5 cal kyr BP, the climatic conditions were mainly controlled by the ISM. From 11.6 to 9 cal kyr BP, the TP was exposed to enhanced solar radiation at the low latitudes, resulting in greater water availability.