Oxygen isotope signatures preserved in tree ring cellulose as a proxy for April–September precipitation in Fujian, the subtropical region of southeast China

Abstract

AbstractA tree ring cellulose oxygen isotope (δ18O) chronology for the period 1870–2011 was established using samples from four Fokienia hodginsii trees with the aim of exploring the potential to use tree ring δ18O records to reconstruct climatic variations in Fujian, a subtropical region of southeast China. We believe that this is the first tree ring δ18O chronology from this area. Response analysis revealed that tree ring δ18O is significantly correlated with precipitation between April and September, relative humidity between August and October, and the Palmer drought severity index between April and October. Our δ18O chronology accounts for 37.4% (24.6%) of actual variation in precipitation between April and September during the period from 1951 to 2011 (1901 to 2011). Spatial correlation analysis revealed that tree ring cellulose δ18O is a suitable proxy for reconstructing April–September precipitation in Fujian, as well as in parts of Guangdong and Jiangxi, southeast China. In addition, significant correlations between δ18O chronology and the Indian summer monsoon index show that large‐scale atmosphere circulation also influences tree ring δ18O. Comparisons between the tropical Pacific sea surface temperature (SST) and tree ring δ18O, during the period from 1895 to 2009, indicate that the tropical Pacific SST is positively correlated with tree ring δ18O in the study region over the last 110 years, except between 1920 and 1960. Reduced El Niño–Southern Oscillation (ENSO) variance from 1920 to 1960 may result in collapsed relationship between tree ring δ18O in Fujian and tropical Pacific SST.