Reconstruction of seasonal precipitation anomalies from tree-ring latewood records in southeastern China

To investigate variations in inter-annual to decadal warm season precipitation in southeastern China, we developed new tree-ring-width chronologies (i.e., tree-ring-width: TRW; earlywood width: EWW; latewood width: LWW; and adjust latewood width: LWWa) for Pinus massoniana from three sampling sites where the sensitivity of climatic proxy is weak. Our results demonstrate that ring-width chronologies positively correlate with precipitation and moisture conditions, while negatively correlating with temperature during the growing season. A regional LWW chronology (spanning 1833-2015) derived from three site series shows a strong positive precipitation sensitivity during the warm season (May-October, r = 0.66), signifying reduced LWW growth in years of insufficient precipitation. We reconstructed warm season precipitation (PREC5-10) for the period 1833-2015, achieving robust calibration-verification statistics. Our reconstruction identified 11 extremely dry and 29 extremely wet years over the past 183 years. We validated the reconstruction by comparing it with other hydroclimatic reconstructions and historical records from neighboring regions. Wavelet analysis revealed that PREC5-10 is dominated by interdecadal (8-24 year) variations. From 1940 to 1980, interdecadal fluctuation intensified, becoming significant, and the relationship between PREC5-10 and sea surface temperature (SST) in the Pacific Ocean exhibited a Pacific Decadal Oscillation (PDO)-like pattern. PDO influences precipitation changes in southeastern China by altering atmospheric circulation over East Asia, thus affecting the interdecadal variation of precipitation in the region. Our findings highlight the utility of intra-annual tree-ring indices for reconstructing seasonal hydroclimate changes in humid regions of China and provide valuable insights into the impacts of extreme weather events related to hydroclimate variations in southeastern China.