A study finds evidence of the history of the Taklimakan desert in China preserved in wind-blown dust, with implications for the effects of global cooling on the climate of midlatitude Asia. The Taklimakan desert, in the midlatitudes of Asia, is a source of global dust and home to thick deposits of loess, wind-blown silt-rich dust. The dust produced in the region is thought to influence Pacific Ocean productivity and global radiation budget, but the mechanisms of aridification of the region are unclear. Zhisheng An, Xiaomin Fang, and colleagues examined a 671-m borehole sequence containing loess that provides a record covering the past 3.6 million years. The record suggests continuous loess deposition, indicating that the area experienced a dry climate, desert conditions, and a stable land surface over that time period. The record suggests a stepwise drying pattern, with steps at around 2.7, 1.1, and 0.5 million years ago. The steps correlate with global variability in ice volume, and numerical modeling further suggests that global cooling may drive midlatitude drying. According to the authors, global cooling can dry the Asian midlatitudes and intensify westerly winds, enhancing dust production and transport.
Article #19-22710: "The 3.6-Ma aridity and westerlies history over midlatitude Asia linked with global climatic cooling," by Xiaomin Fang et al.
MEDIA CONTACT: Zhisheng An, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, CHINA; e-mail: anzs@loess.llqg.ac.cn
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Proceedings of the National Academy of Sciences