Reconstruction of Early-Spring Temperature of Qinling Mountains Using Tree-Ring Chronologies
利用树轮重建秦岭地区历史时期初春温度变化

In this paper, tree ring chronologies were used to reconstruct early-spring temperature in the Qinling Mountains of China. The reconstructed series and the instrument data are well correlated, which the maximum correlation coefficient is up to 0.7 at Zhen'an meteorological station, and that of other stations are above 0.6. So the early-spring temperature changes are well reflected by the reconstructed series in this region. Three warm periods, which are from 1715 to 1740, from 1773 to 1804 and from 1893 to 1958, with 26-year, 32-year and 66-year durations respectively, could be detected in the last 300 years, and three cool periods, which are from 1741 to 1772, from 1805 to 1892 and from 1959 to 1992, with 32-year, 88-year and 34-year durations respectively, could also be detected. It is showed that the early-spring temperature in the region increases quickly and decreases slowly, with changes being consistent with the consequences of other researches. Neither the reconstructed series nor the instrument data has significant warming trend before 1992 in the latter part of the 20th century. For the extent of warm or cool period, the early-spring temperature of the west Qinling Mountains is larger than that of the east. The 100-year, 50 to 60-year, 7 to 8-year and 2 to 3-year period cycles can be detected in the reconstructed early-spring temperature series.