Evolution of Near‐Surface Wind Strength in Northeastern Arid Central Asia During the Holocene

Abstract

Arid central Asia is one of the most important nonzonal arid regions in the central and eastern part of the middle latitude Eurasian continent (Chen et al., 2008). Northeastern arid central Asia is one of the most important sources of Asian dust due to its unique geomorphic features and dry climate (Kim & Kai, 2007; Shao & Wang, 2003). It has been demonstrated that the solar radiation balance at the Earth's surface, global atmospheric CO 2 concentration, and global hydrological and biogeochemical cycles can be influenced by dust emissions (e.g., Booth et al., 2012; Ginoux et al., 2004). As a significant natural hazard, dust activity is usually related to dust emissions (Dun, 2019), and the temporal trend in dust activity in the area is closely linked to the near-surface wind (Pi et al., 2017; Xi & Sokolik, 2015). However, there are few studies of wind dynamics on a long temporal scale, such as that of the Holocene, and the lack of knowledge of the trend of variation of near-surface wind strength on a long time scale makes it difficult to determine the factors influencing dust activity in this area. The grain size of bulk samples from loess-paleosol sequences in East Asia has been used as a proxy for the East Asian winter monsoon (Xiao et al., 1995). However, bulk samples of Aeolian sediments comprise both pedogenic clay deflated from the dust source regions and argillic clay produced during postdepositional pedogenesis (Z. An et al., 1991; X. Liu et al., 1992). The clay from postdepositional pedogenesis results in a reduction of the grain size of bulk samples, thereby potentially obscuring information about aeolian transport conditions (Xiao et al., 1995). Quartz is one of the most resistant minerals and its physical and chemical properties are very stable during erosion, transport, postdepositional weathering, and pedogenesis. Thus the