A tree-ring based precipitation reconstruction for the Baluntai region on the southern slope of the central Tien Shan Mountains, China, since A.D. 1464

摘要

July-June precipitation has been reconstructed back to A.D. 1464 for the Baluntai region on the southern slope of the central Tien Shan Mountains, China, using the Picea schrenkiana tree-ring width. The reconstruction explains the variance of 51% in the observed precipitation from 1959 to 2005. By employing a 21-year moving average to the reconstruction, nine periods with above average reconstructed precipitation comprised ～1474-1503,1550-1577,1588-1619,1658-1713,1790-1812,1833-1867,1890-1907, 1923-1944, and 1988-1995 ～; eight periods with below average reconstruction consisted of 1504-1549, 1578-1587, 1620-1657, 1714-1789, 1813-1832, 1868-1889, 1908-1922 and 1945-1987. The wet/dry periods of the reconstructed precipitation correspond well with other reconstructions. Some droughts in the historical documents are also precisely captured in the reconstruction. Precipitation variations for the southern slope of the central Tien Shan Mountains are roughly synchronous with that of the northern slope in the recent ～300 year. Power spectral and wavelet analysis demonstrated the existence of significant ～100-y, ～60-y, ～50-y, ～16-y, ～10-y and ～2-y cycles of variability.