Climate change has a profound impact on historical societal transformations. Enhancing the comprehension of the interaction mechanism between climate change and civilization development can offer valuable historical insights for humanity to address the challenges posed by global change. Hydroclimatic fluctuations are of paramount importance in the historical changes of China. 

The collapse of the Ming Dynasty, one of the most important dynasties in Chinese history, has attracted public and scientific interest. Previous studies have mostly focused on the famous "Chongzhen Drought" of the late Ming Dynasty, considering it to be an important factor in the decline of the Ming Dynasty. However, relatively little is known about other severe drought events and their potential impact on dynasty collapse. In addition, previous studies have been limited by the insufficiency of data resolution and dating precision, the characteristics of an exceptional climatic anomaly termed the “Late Ming Weak Monsoon Period” are unclear, which limited our comprehensive understanding of the intrinsic relationship between the decline of the Ming Dynasty and climate change.

Recently, a research team led by the Institute of Earth Environment of the Chinese Academy of Sciences successfully reconstructed the historical variations of Palmer Drought Severity Index for July–September based on tree-ring stable oxygen isotopes (δ¹⁸O) from 1556 CE to 2015 CE in southwest Chinese Loess Plateau (Fig.1). 

The researchers reveal a significant weakening of the Asian summer monsoon between 1561 CE and 1661 CE, consistent with the Late Ming Weak Monsoon Period (1580–1660 CE), and analyze the specific characteristics of this climatic anomaly in details. The reconstruction also captures a distinct humidification trend over northwest China since the 2000s, which coincides with the general trend of warm-humid climate in northwest China.

Notably, in addition to the well-known Chongzhen megadrought, this study records the severe Wanli megdrought (1585–1590 CE) during the late Ming Dynasty, an event that rarely featured in earlier studies, exhibiting comparable duration and severity to the Chongzhen megadrought. Further analysis indicates that Wanli megadrought may have served as an early trigger for the collapse of the Ming Dynasty. Furthermore, the analysis implicates the ENSO as a contributing factor in both the Wanli and Chongzhen megadroughts, and thus to the ultimate collapse of the Ming Dynasty by affecting the Asian summer monsoon intensity.

This work published in Palaeogeography, Palaeoclimatology, Palaeoecology, was funded by the Natural Science Basic Research Program of Shaanxi Province, the National Natural Science Foundation of China, the 2nd Tibetan Plateau Scientific Expedition and Research, the Chinese Academy of Sciences.

Fig. 1 July–September sc PDSI reconstruction from 1556 CE to 2015 CE (Image by REN, et al)