资源环境科技发展态势分析平台

Hydroclimate variations inferred from proxies, such as tree rings, provide a long-term context for the understanding of the current climate change. In humid Southeastern China (SEC), relatively limited long-term tree-ring records were published due to the paucity of old trees. This study develops a robust tree-ring width chronology from the Chinese cedar (Cryptomeria fortune) Fengshui woods, spanning from 1781 to 2015, by far the longest in SEC. Common growth anomalies of the Fengshui trees can well capture long-term springtime (March-May) Standardized Precipitation Evapotranspiration Index (SPEI) changes over the past 230 years in SEC. This hydroclimate-sensitive chronology shows significant correlations with El Nino-Southern Oscillation (ENSO) like sea surface temperature modes, indicating that ENSO may act as an important regulator in local springtime SPEI. However, interdecadal shifts in the relationships between the variances of tree rings and ENSO reveal that the ENSO-SPEI teleconnection over SEC was an unstable process, and it collapsed during the periods of 1820s-1860s and 1920s-1960s, when ENSO was in its decaying phases.