A tree-ring width based drought reconstruction for southeastern China: links to Pacific Ocean climate variability.

We present a drought reconstruction for southeastern China based on a tree-ring width chronology of Cryptomeria fortunei developed from two sampling sites in central Fujian. A reconstruction of July-February drought variability, spanning AD 1855-2011, was developed by calibrating total tree-ring width data with the self-calibrating Palmer drought severity index (sc PDSI). The reconstruction was verified against an independent data set, and accounts for 36% of the actual sc PDSI variance during the period 1955-2011. Relatively dry intervals were reconstructed between AD 1859-1880, 1899-1911, 1927-1933, 1946-1959, 1964-1970 and 1987-1997. Relatively wet conditions prevailed during 1855-1858, 1881-1898, 1912-1926, 1934-1945, 1960-1963, 1971-1986 and 1998-2011. Comparisons between our scPDSI reconstruction and a moisture-sensitive tree-ring width record from Vietnam revealed consistencies between the two data sets, suggesting similar drought regimes. Spectral peaks of 2.2-6.4 years may be indicative of El Niño-Southern Oscillation ( ENSO) activity, as also suggested by the significant correlations with sea surface temperatures ( SSTs) in the eastern equatorial and southeastern Pacific Ocean and an extreme event analysis. The analysis of links between our sc PDSI reconstruction and the large-scale regional climatic variation shows that there is a relationship between regional drought variation and East Asian summer monsoon (EASM) intensity. [ABSTRACT FROM AUTHOR]