Drought can negatively affect water resources and, therefore, is a major threat to food security and agricultural production, especially in the arid and semi-arid regions. Many areas of midlatitude East Asia have experienced drying in recent decades (P. Zhang et al., 2020), which have severe effects on ecosystems and socioeconomics (H. Liu et al., 2013). Warming is expected to continue in the near future, which may increase evaporation and thus exacerbate droughts in some areas . Considering the prevalent influence of drought, there is an urgent need to better understand the recent drying. The recent drying, however, has mostly been studied with short-term instrumental climate data, which may hinder our ability to understand it in a long-term context (Williams et al., 2022). Knowledge of the mechanism of drought variation is a prerequisite for accurate prediction of its variation in the future. However, human activities have greatly influenced the current climate system (e.g., Chiang et al., 2021;Y. Sun et al., 2022), potentially complicating insight into the mechanisms of climate variation (e.g., Marvel et al., 2019). Long-term climate history devoid of anthropogenic impacts would allow for a better understanding of the forcing mechanisms underlying drought variation (e.g., Gou et al., 2014), potentially leading to more accurate forecasting.Paleoclimate proxy data are an important source for extending the observed climate and have improved our knowledge of past climate variation. Based on different types of proxy data, many studies have reconstructed past climate variation in or around the midlatitude East Asia (e.g., Treydte et al., 2006;Yadav et al., 2017;P. Zhang et al., 2020). However, existing studies generally reconstructed past climate variation using proxy data from one or a few sites, and thus generally can only represent the climate variation of those sites or surrounding areas (e.g.,