1970-2015年秦岭南北气温时空变化及其气候分界意义  

Spatiotemporal variability of temperature in northern and southern Qinling Mountains and its influence on climatic boundary

作　　者：李双双 芦佳玉[1,2] 延军平 刘宪锋 孔锋[3] 王娟 

机构地区：[1]陕西师范大学地理科学与旅游学院,西安710119 [2]陕西师范大学地理国家级实验教学示范中心,西安710119 [3]中国气象局发展研究中心,北京100081 [4]陕西省气象局,西安710014

出　　处：《地理学报》2018年第1期13-24,共12页Acta Geographica Sinica

基　　金：国家自然科学基金项目(41701592);中央高校基本科研业务费专项资金(GK201703048);国家社会科学基金重点项目(14AZD094)~~

摘　　要：基于秦岭南北70个气象站点观测资料,辅以极点对称模态分解方法(ESMD),对秦岭南北近期气温时空变化特征进行分析,进而以日平均温≥10℃积温天数为主要指标,以1月0℃等温线变化为辅助指标,探讨秦岭山脉的气候分界意义。结果表明:(1)1970-2015年秦岭南北气温变化具有同步性,呈现出"非平稳、非线性、阶梯状"的增暖过程,变化阶段可分为:1970-1993年为低位波动期、1994-2002年为快速上升期、2003-2015年为增温停滞期;(2)ESMD信息分解结果表明,秦岭南北气温变化以年际波动为主导,并未呈现出明显的线性增暖趋势;(3)在空间上,秦岭南北气温趋势呈现"同步增温,南北分异"的响应特征,即秦岭以北地区空间增温具有一致性,秦岭以南地区则呈现"西乡—安康盆地交界"、"商丹盆地"两个低值中心;(4)在气候变暖背景下,秦岭作为气候分界线的作用依然明显,但是南北响应方式存在差异。其中,秦岭以南,北亚热带北界沿山地"垂直上升",汉江谷地热量资源逐年增加;秦岭以北,尽管以城市带为中心的增温区不断延展,但是冷月气温偏低的格局并未改变。A study on temperature variations in the northern and southern Qinling Mountains is performed using temperature series at 70 meteorological stations for the period 1970-2015.Temporal trends, spatial characteristics, 0 ℃ isotherm displacement and the number of days with active accumulated temperature above 10 ℃ are evaluated, using extreme-point symmetric mode decomposition（ESMD）, spatial analysis and other climate diagnosis methods. The significance of climatic boundary line of the Qinling Mountains is explored in the context of global warming. Four new insights have been achieved：（1） The changing trends of temperature in the northern and southern Qinling Mountains over the past 46 years are synchronous, with the warming process shown as a ＇non-smooth, nonlinear, and ladder-shaped＇ pattern. The evolution process can be divided into three periods： the low stationary fluctuation period in 1960-1993, followed by a rapid increase period in 1994-2002, and finally a warming stagnation period in 2003-2015.（2） The ESMD decomposition indicates that the changing trends of temperature over the northern and southern Qinling Mountains are dominated by interannual fluctuation, and have no obvious linear trend.（3） The spatial variation of temperature in the Qinling Mountains is characterized by ＇synchronous warming, and differential north-south change＇. In the north, the spatial variation of temperature is relatively consistent, while in the south low temperature centers are observed at Xixiang-Ankang basin and Shangdan basin.（4）The Qinling Mountains, as a climatic boundary line, still play a major/obvious role; however,there exists difference in the response of temperature variations to global warming over the north and south of the Qinling Mountains. The northern boundary of north subtropical zone extends upward along the southern Qinling Mountains; while warming zone extends by the form of enclave in the northern Qinling Mountains due to rapid urbanization and mountain blocking.

关 键 词：气温 极点对称模态分解 中国南北过渡带 秦岭山地 

分 类 号：P423[天文地球—大气科学及气象学]