East Asian paleoclimate change in the Weihe Basin (central China) since the middle Eocene revealed by clay mineral analysis

Author(s):  
Hengzhi Lyu ◽  
Huayu Lu ◽  
Yichao Wang ◽  
Hanzhi Zhang ◽  
Yao Wang ◽  
...  
2021 ◽  
Vol 13 (9) ◽  
pp. 4848
Author(s):  
Liwei Wu ◽  
Xinling Li ◽  
Qinghai Xu ◽  
Manyue Li ◽  
Qiufeng Zheng ◽  
...  

The East Asian monsoon system is an important part of global atmospheric circulation; however, records of the East Asian monsoon from different regions exhibit different evolutionary rhythms. Here, we show a high-resolution record of grain size and pollen data from a lacustrine sediment core of Dajiuhu Lake in Shennongjia, Hubei Province, China, in order to reconstruct the paleovegetation and paleoeclimate evolution of the Dajiuhu Basin since the late Middle Pleistocene (~237.9 ka to the present). The results show that grain size and pollen record of the core DJH-2 are consistent with the δ18O record of stalagmites from Sanbao Cave in the same area, which is closely related to the changes of insolation at the precessional (~20-kyr) scale in the Northern Hemisphere. This is different from the records of the Asian summer monsoon recorded in the Loess Plateau of North China, which exhibited dominant 100-kyr change cyclicities. We suggest that the difference between paleoclimatic records from North and South China is closely related to the east–west-oriented mountain ranges of the Qinling Mountains in central China that blocked weakened East Asia summer monsoons across the mountains during glacial periods.


2021 ◽  
Vol 558 ◽  
pp. 116758
Author(s):  
Yanjun Cai ◽  
Xing Cheng ◽  
Le Ma ◽  
Ruixue Mao ◽  
Sebastian F.M. Breitenbach ◽  
...  

2015 ◽  
Vol 2015 ◽  
pp. 1-15 ◽  
Author(s):  
Hui Sun ◽  
Xiaodong Liu

Variations of the East Asian winter monsoon (EAWM) induced by dust aerosol are studied by using a regional climate model (RegCM4/Dust). Dust coupled and uncoupled experiments are carried out for the past decade (2000–2009). The coupled RegCM4 captures three centers of dust mixing ratio (DMR) located in the Taklamakan Desert, western Inner Mongolia, and northern Xinjiang, respectively, with maximum values greater than 500 µg kg−1in winter. The surface total radiation change induced by dust is negative, and its central value of −8 W m−2results in surface temperature cooling by 1.5°C in winter. Dust induced radiation change at the top of the atmosphere (TOA) is also negative in Northern China, except over the Tibetan Plateau (TP), and up to −5 W m−2in Central China. Dust cooling effects increase the sea level pressure (SLP) gradient between land and ocean, the cold surge frequency, and the East Asian jet stream (EAJ) intensity and then enhance the EAWM. The dry and cold wind pervade most areas of East Asia, suppressing large-scale precipitation and eventually leading to a rainfall decrease of about 10–30% in Northern China and the middle Yangtze River Valley.


2020 ◽  
Vol 6 (46) ◽  
pp. eabc2414
Author(s):  
Yichao Wang ◽  
Huayu Lu ◽  
Kexin Wang ◽  
Yao Wang ◽  
Yongxiang Li ◽  
...  

East Asian monsoon variability in the Pliocene warm world has not been sufficiently studied because of the lack of direct records. We present a high-resolution precipitation record from Pliocene fluvial-lacustrine sequences in the Weihe Basin, Central China, a region sensitive to the East Asian monsoon. The record shows an abrupt monsoon shift at ~4.2 million years ago, interpreted as the result of high-latitude cooling, with an extratropical temperature decrease across a critical threshold. The precipitation time series exhibits a pronounced ~100–thousand year periodicity and the presence of precession and half-precession cycles, which suggest low-latitude forcing. The synchronous phase but mismatched amplitudes of the East Asian monsoon precipitation proxy and eccentricity suggest a nonlinear but sensitive precipitation response to temperature forcing in the Pliocene warm world. These observations highlight the role of high- and low-latitude forcing of East Asian monsoon variations on tectonic and orbital time scales.


2020 ◽  
Vol 193 ◽  
pp. 103269 ◽  
Author(s):  
Lin Zhao ◽  
Huayu Lu ◽  
Hanlin Wang ◽  
Michael Meadows ◽  
Chunmei Ma ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document