树木年轮记录的新疆新源350a来温度变化

Variations of temperature during last 350 years at Xinyuan recorded by tree-ring

利用位于天山西部伊犁河谷巩乃斯河源区的雪岭云杉树轮宽度资料,分析了树木径向生长与相邻气象站点气象资料的关系,发现树轮指数与新源气象站7-8月的降水正相关,与7-8月最高气温显著负相关,且存在明显的滞后效应,表明这一区域树木生长主要受水份条件限制。生长季期间的高温导致蒸发量增加,不利于树木当年和次年的生长。利用树轮宽度年表指数重建了新源站350a来7-8月最高气温,重建方程方差解释量为52.0%。各种检验参数表明,重建方程是稳定的。对重建序列进行的特征分析表明:新源350a以来7-8月最高气温经历了5个偏暖和5个偏冷阶段,重建序列存在2a的周期变化;在1733年,1778年,1832年,1871年,1920年,1955年前后发生了突变,其中1920年前后的突变与北半球气温的突变年份一致。

Based on the tree-ring width index from the source area of Gongnasi River located at Yili catchment,we analyzed the relationship between tree ring radial growth and meteorological data,it indicated that the tree ring index was positive to the precipitation of July to August,however,negative to the highest temperature of July to August.Summer moisture was the limited factor to tree growth in this region,the enhancement of evaporation resulted by high temperature at growth season was unfit for the tree growth in the current and next year.The highest temperature of July to August was reconstructed by tree ring chronologies.The reconstruction function was stable with an explain variance of 52.0%.The reconstructed temperature series showed five warm and five cold periods,and a 2 year cycle.Abrupt changes happened at 1733,1778,1832,1871,1920,1955,in which,the abrupt year around 1920 was consistent with the temperature of northern hemisphere.