Understanding the causes and consequences of the northward extension of the tropical monsoon in Asia in the Eocene
Understanding the causes and consequences of the northward extension of the tropical monsoon in Asia in the Eocene
复制标题
DOI：
10.1016/j.palaeo.2023.111613
复制
发表时间：
2023-04
期刊：
影响因子：
--
通讯作者：
Zijian Zhang;Zhongshi Zhang;Q. Yan;Zhilin He;N. Tan;Zhengtang Guo
中科院分区：
文献类型：
--
作者：
Zijian Zhang;Zhongshi Zhang;Q. Yan;Zhilin He;N. Tan;Zhengtang Guo
以往的地质研究表明，早第三纪东亚中纬度地区普遍存在着纬向干旱带的气候模式。在干旱带的南部，热带季风气候控制了华南、中南半岛和印度。在始新世，干旱气候和热带季风气候的分界线大幅度北移。然而，这一变化背后的原因尚不清楚。本文利用挪威地球系统模式（NorESM 1-F）的快速版本，在不同的始新世古地理条件下，对始新世早期至始新世晚期亚洲热带季风的演化进行了实验分析。结果表明，夏季印度板块的北移导致低层西风带的重组。印度-亚洲大陆完全合并后，形成了类似现代的低层热带环流，并导致了华南地区的增湿。
Previous geological studies have revealed that a zonal climate pattern with an arid zonal band prevailed in the mid-latitude of East Asia in the Paleogene. On the south of the arid band, a tropical monsoon climate controlled South China, Indochina, and India. In the Eocene, the boundary between the arid and the tropical monsoon climate largely moved northward. However, the reason behind this change remains unclear. Here, with the fast version of the Norwegian Earth System Model (NorESM1-F), we conduct experiments under different Eocene paleogeography conditions to analyze the evolution of the tropical Asian monsoon from the early Eocene to the late Eocene. Our results demonstrate that the northward movement of Indian plate causes a reorganization in low-level westerlies in summer. After the full merging of the India-Asia continents, modern-like low-level tropical circulations come into being and lead to the wetting in southern China.