We utilised tree-ring cores, collected from three sites at Lingkong Mountain located in the southeast part of the Chinese Loess Plateau (CLP), to develope a regional ring-width chronology. Significant positive correlations between the tree-ring index and the monthly Palmer drought severity index (PDSI) were identified, indicating that the radial growth of trees in this region was moisture-limited. The March–August mean PDSI was quantitatively reconstructed from 1703 to 2008 with an explained variance of 46.4%. Seven dry periods during 1719–1726, 1742–1748, 1771–1778, 1807–1818, 1832–1848, 1867–1932 and 1993–2008 and six wet periods during 1727–1741, 1751–1757, 1779–1787, 1797–1805, 1853–1864 and 1934–1957 were revealed in our reconstruction. Among them, 1867–1932 and 1934–1957 were identified as the longest dry and wet periods, respectively. On the centennial scale, the 19th century was recognised as the driest century. The drying tendency since 1960s was evident. However, recent drought in 1993–2008 was still within the frame of natural climate variability based on the 306 yr PDSI reconstruction. The dry and wet phases of Lingkong Mountain were in accordance with changes in the summer Asian-Pacific oscillation (I_APO) and sunspot numbers, they also showed strong similarity to other tree-ring based moisture indexes in large areas in and around the CLP, indicating the moisture variability in the CLP was almost synchronous and closely related with large-scale land–ocean–atmospheric circulation and solar activity. Spatial correlation analysis suggested that this PDSI reconstruction could represent the moisture variations for most parts of the CLP, and even larger area of northern China and east Mongolia. Multi-taper spectral analysis revealed significant cycles at the inter-annual (2–7 yr), inter-decadal (37.9 yr) and centennial (102 yr) scales. Results of this study are very helpful for us to improve the knowledge of past climate change in the CLP and enable us to prevent and manage future natural disasters.

Given growing concerns about global climate change, it is critical to understand both historical and current shifts in the hydroclimate, particularly in regions critically entwined with global circulation. The Tibetan Plateau, the Earth’s largest and highest plateau, is a nexus for global atmospheric processes, significantly influencing East Asian hydroclimate dynamics through the synergy of the Asian Monsoon and the Westerlies. Yet, understanding historical and recent hydroclimate fluctuations and their wide-ranging ecological and societal consequences remains challenging due to short instrumental observations and partly ambiguous proxy reconstructions. Here, we present a precisely-dated 3476-year precipitation reconstruction derived from tree-ring δ¹⁸O data on the Tibetan Plateau, representing one of the few multi-millennia-long annually-resolved terrestrial δ¹⁸O records to date. Our findings reveal that the 20^th century drought extremes are severe within the past three millennia, and likely linked to the weakening of both the Asian Monsoon and Westerlies due to anthropogenic aerosol emissions. Additionally, our analyses identified three distinct stages (110 BC–AD 280, AD 330–770 and AD 950–1300) characterized by shifts toward arid hydroclimate conditions, corresponding to significant social unrest and dynasty collapses, which underscores the potential societal impacts of severe hydroclimatic shifts.