Centennial- to decadal-scale monsoon precipitation variability in the semi-humid region, northern China during the last 1860 years: Records from stalagmites in huangye cave

We developed a composite oxygen isotopic record of cave calcite for the last 1860 years based on three stalagmites from the Huangye Cave in eastern Gansu Province, northern China. The δ¹⁸O values reflect monsoon precipitation changes, with lower δ¹⁸O values representing higher precipitation and vice versa. Three intervals of high precipitation were identified at AD 138-450, AD 730-1200, and AD 1860-1960. Two intervals of low precipitation occurred at AD 1320-1410 and AD 1530-1860. The reconstructed monsoon precipitation variations correlate well with other records further east in the eastern Yellow River Basin, suggesting synchronous precipitation changes during the late Holocene in the semi-humid region of northern China on decadal to centennial scales. Peak periods of warfare in dynastic transition times, such as at AD 391-420, AD 601-630, AD 1111-1140, AD 1351-1380, and AD 1621-1650, correspond to sharp declines in precipitation or temperature in semi-humid northern China, indicating a strong connection between climatic and societal changes. Our study suggests that climatic deterioration in semi-humid northern China has played an important role in Chinese societal evolution.