Over 400 major flood disasters have been documented in the Pearl River basin over the past 2,000 years. Model simulations even suggest that future surface warming can enhance both the intensity and frequency of extreme rainfall in this region.

To assess the prediction of future catastrophic floods, an international team of scientists led by Prof. Zhuo Zheng (School of Earth Sciences and Engineering, Sun Yat-sen University) and Prof. Yongqiang Zong (Guangzhou Institute of Geography, Guangdong Academy of Sciences) sought to reconstruct the detailed history of great floods in the lower Pearl River area.

The paper, "Holocene millennial-scale megaflood events point to ENSO-driven extreme climate changes," is published in the journal Science China Earth Sciences.

In this study, Cong Chen and a research team report a series of white to gray clay layers interbedded sharply with wood-rich peat sediments in Gaoyao County, west of the Pearl River Delta. Through profile correlation, sedimentary analysis, and radiocarbon dating, they identified seven clay layers with 5–40 cm thickness covering the past 6,000 years, interpreted as flood deposits (designated FL1–FL7). These floods had an average return period of approximately 855 years, with an average water volume estimated to be 1.5-times that of the once-in-a-century Yimao Flood in July 1915.