1961-2016年秦岭山区冷季积雪日数变化特征及其影响因子  

The variation characteristics of snow cover days and its influencing factors in cold season in the Qinling Mountains from 1961 to 2016

作　　者：李茜[1] 魏凤英[2] 雷向杰[1] LI Qian;WEI Fengying;LEI Xiangjie(Climate Center of Shaanxi Province,Xi’an 710015,China;State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081,China)

机构地区：[1]陕西省气候中心,陕西西安710015 [2]中国气象科学研究院灾害天气国家重点实验室,北京100081

出　　处：《冰川冻土》2020年第3期780-790,共11页Journal of Glaciology and Geocryology

基　　金：中国气象局气候变化专项(CCSF201845);陕西省自然科学基础研究计划项目(2019JQ-990)资助。

摘　　要：根据1961-2016年秦岭地区32个气象站点的气温、降水及积雪等相关数据,运用REOF、M-K检验和小波分析等方法,对秦岭地区冷季积雪日数的时空变化和影响因子进行分析。结果表明:秦岭地区冷季多年平均积雪日数表现为北坡比南坡积雪日数多。在全球气候变暖的背景下,海拔越高积雪日数减少的越多。秦岭冷季积雪日数呈现显著减少的趋势,5个区的积雪日数年代际变化特征显著,在20世纪末到21世纪初发生了由积雪日数偏多到偏少的突变。各区冷季积雪日数的周期变化主要集中在10~20a,秦岭南坡同时也显示了较为明显的4a左右的周期变化。西北太平洋海温阶段性增暖是导致秦岭冷季积雪日数减少的外强迫因素。秦岭地区冷季平均气温的显著增暖和冷季降水量的显著减少直接造成积雪日数的减少。秦岭冷季积雪日数减少的突变要比气温增暖的突变大约滞后4~7a。Based on the data of temperature,precipitation and snow cover days in the Qinling Mountains from1962 to2016 from32 meteorological stations,the spatial and temporal changes and influence factors in the cold season,snow cover days were analyzed by REOF,M-K test and wavelet analysis.It is found that the average snow cover days in the cold season of the Qinling Mountains is higher than that in its southern slopes.There are more snow cover days in the higher altitude.Under global climate change,the snow cover days decrease rapidly.The snow cover days are significantly decreasing in the cold season.There are five districts where the decadal variation of snow cover days are significant.From the end of the20 th century to the beginning of the21 st century,there were sudden changes in snow cover days.The periodic changes of snow cover days in the cold season mainly concentrated in10~20 a,and there were also have obvious4 a period in the southern slopes of the Qinling Mountains.The seasonal increase of SST in the northwest Pacific Ocean was the external forcing factor for the decrease of snow days in cold season in the Qinling Mountains.The significant increase of mean temperature in cold season and the significant decrease of precipitation in cold season in the mountains directly resulted in the decrease of snow cover days.In the Qinling Mountains,the abrupt change of decreasing number of snow days in cold season lagged behind the abrupt change of temperature increase by about4~7 a.

关 键 词：秦岭 冷季 积雪日数 平均气温 

分 类 号：P468.025[天文地球—大气科学及气象学]