2025-04-21 中国科学院（CAS）
＜関連情報＞
- https://english.cas.cn/newsroom/research_news/earth/202504/t20250421_1041624.shtml
- https://www.the-innovation.org/article/doi/10.59717/j.xinn-geo.2025.100141
気温と地形隆起の相互作用が漸新世以降の東アジアモンスーン降雨の進化を形成した Interactive forces of temperature and topographic uplift shaped the East Asian monsoon rainfall evolution since the Oligocene
Shiming Wan, Debo Zhao , Hualong Jin, Yingying Sha, Zhengguo Shi, Peter D. Clift, Zhimin Jian, Chang Liu, Carlos Alvarez Zarikian, Christian France-Lanord, Zhaojie Yu, Jin Zhang, Wenjun Jiao, Xuebo Yin, Anchun Li
The Innovation Geoscience Published:14 April 2025
DOI:https://doi.org/10.59717/j.xinn-geo.2025.100141
GRAPHICAL ABSTRACT
PUBLIC SUMMARY
- A 30 Ma monsoon rainfall history of East Asia was reconstructed with weathering records in South China Sea.
- Monsoon rainfall was primary driven by global climate but disrupted by Himalayas and Tibetan Plateau uplift.
- Monsoon rainfall at the cold Pliocene was comparable with the warm Oligocene due to the topographic uplift.
ABSTRACT
The debate concerning the long-term evolution of the East Asian summer monsoon (EASM) and its governing mechanisms persists, often attributed to either the uplift of the Tibetan Plateau or global temperature changes. This disagreement arises from the scarcity of comprehensive, high-resolution monsoon records. Utilizing continuous sedimentary records from the South China Sea and a weathering-rainfall-temperature regression model, we have quantified the evolution of EASM rainfall in South China since 30 Ma. Our findings indicate that, apart from a notable and sustained increase in monsoon rainfall between approximately 21 and 13 Ma, rainfall patterns generally mirrored global temperature trends, suggesting that global climate change was the primary controlling factor. Based on model simulations, we attribute the anomalous enhanced EASM during ~21‒13 Ma primarily to the dominant influence of the major uplift of the Himalaya-Tibetan Plateau, with temperature effects playing a limited background role. This topographic change disrupted the close coupling between temperature and rainfall, resulting in a relatively humid and habitable East Asia despite the ongoing global cooling trend since the late Miocene. This study clearly disentangles the roles of long-term temperature regulation and the short-term impacts of Himalaya-Tibetan Plateau uplift on the evolution of the EASM since 30 Ma.
