Sedimentological Evidence for Pronounced Glacial‐Interglacial Climate Fluctuations in NE Tibet in the Latest Pliocene to Early Pleistocene
Sedimentological Evidence for Pronounced Glacial‐Interglacial Climate Fluctuations in NE Tibet in the Latest Pliocene to Early Pleistocene
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DOI：
10.1029/2020pa003864
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发表时间：
2020-05
影响因子：
3.5
通讯作者：
Yin Lu;Nico Dewald;A. Koutsodendris;Stefanie Kaboth‐Bahr;W. Rösler;X. Fang;J. Pross;E. Appel
中科院分区：
文献类型：
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作者：
Yin Lu;Nico Dewald;A. Koutsodendris;Stefanie Kaboth‐Bahr;W. Rösler;X. Fang;J. Pross;E. Appel
北方半球冰川作用的加强和青藏高原的隆升是上新世/更新世中亚中纬度地区气候变化的主要驱动力之一。虽然大多数支持这一假设的代用记录来自青藏高原以外的地区（如中国黄土高原），但当时高原本身的详细古气候信息仍然难以捉摸。在这里，我们提出了一个时间上高分辨率（~500年）的沉积学记录，从柴达木盆地位于青藏高原东北部，显示出显着的冰期-间冰期气候变化的时间间隔为2.7至2.1马。冰期（间冰期）间隔的特征通常是粒度较粗（较细）、有机质含量最小（最大）和碳酸盐含量最大（最小）。我们的结果与地球的轨道参数和代理记录从中国黄土高原的比较表明，观测到的气候波动主要是由西伯利亚高压/东亚冬季风系统的变化作为对iNHG的响应。青藏高原的地形及其对西风带位置和强度的影响将进一步增强这些环流。
The intensification of Northern Hemisphere glaciation (iNHG) and uplift of the Tibetan Plateau have been argued to be among the main drivers of climate change in midlatitude Central Asia during the Pliocene/Pleistocene. While most proxy records that support this hypothesis are from regions outside the Tibetan Plateau (such as from the Chinese Loess Plateau), detailed paleoclimatic information for the plateau itself during that time has yet remained elusive. Here we present a temporally highly resolved (~500 years) sedimentological record from the Qaidam Basin situated on the northeastern Tibetan Plateau that shows pronounced glacial‐interglacial climate variability during the interval from 2.7 to 2.1 Ma. Glacial (interglacial) intervals are generally characterized by coarser (finer) grain size, minima (maxima) in organic matter content, and maxima (minima) in carbonate content. Comparison of our results with Earth's orbital parameters and proxy records from the Chinese Loess Plateau suggests that the observed climate fluctuations were mainly driven by changes in the Siberian High/East Asian winter monsoon system as a response to the iNHG. They are further proposed to be enhanced by the topography of the Tibetan Plateau and its impact on the position and intensity of the westerlies.