Tree-ring-based precipitation reconstruction for Mt. Xinglong, China, since AD 1679

摘要

On the basis of a significant correlation between the ring width of Oinghai spruce (Picea crassifolia Kom.) trees at Mt. Xinglong in north-central China and observed instrumental data, a transfer function was designed and the annual precipitation (from the previous July to the current June) was reconstructed for a period spanning 1679-2008 AD with an explained variance of 53.1% (1955-2008 AD). Intervals with precipitation more than the 330-year average occurred in 1686-1715, 1727-1741, 1774-1810 and 1871 -1923. The intervals 1716-1726, 1740-1773, 1811-1870, 1924-1937 and 1980-2003 had precipitation lower than the 330-year average. Most drought events recorded in historical documents were captured by the reconstruction. Moreover, the reconstruction agreed well with tree-ring-based precipitation at Mt. Helan 400 km northeast of Mt. Xinglong. The results showed that the variability of the East Asian summer monsoon-related precipitation was synchronously at a large spatial and temporal scale within the environmentally sensitive region in northern China. The reconstruction was tested for periodicities by power spectrum analysis. The results showed remarkable 160-, 106.67-, 80-, 22.86-, 6.27- and 2- to 3-year cycles at a 99% confidence level for the past 330 years.