气候变化背景下秦岭南北强降雪与小雪时空变化特征  

Variability of heavy and little snowfall in the south and north of the Qinling Mountains under the background of global warming

作　　者：李双双 何锦屏 段克勤 延军平 Li Shuangshuang;He Jinping;Duan Keqin;Yan Junping(School of Geography and Tourism,Shaanxi Normal University,Xi’an 710119,Shaanxi,China)

机构地区：[1]陕西师范大学地理科学与旅游学院,陕西西安710119

出　　处：《地理科学》2024年第5期890-900,共11页Scientia Geographica Sinica

基　　金：国家自然科学基金项目(41701592,41771030)资助。

摘　　要：不同等级降雪变化可反映气候变暖对关键气候变量趋势和极端性的综合影响。基于1970—2018年逐日气象观测数据,辅以湿球温度动态阈值法、趋势分析等气候诊断方法,论文对秦岭南北11月—次年3月强降雪和小雪时空变化特征进行分析,探究3个分区(关中平原、秦岭南坡和汉江谷地)不同等级降雪与气温的响应关系。结果表明:①1970—2018年,秦岭南北11月—次年3月无降水日数增多,固态降水(降雪或雨夹雪)日数明显减少。1998年后,降雪日数比重由前期8.5%下降为5.2%。②秦岭南北小雪降雪量、降雪日数变化显著下降,降雪强度显著上升;强降雪3个指标变化趋势均不显著,说明区域降雪变化以小雪减少为主。③在气温响应关系上,秦岭南北3个子区小雪降雪量、降雪天数与气温显著负相关;关中平原、汉江谷地气温与强降雪量、天数显著负相关,秦岭南坡气温变化与强降雪3个指标相关性较弱。说明河谷平原区是强降雪对气温响应的敏感区。本文研究结论可为理解中国南北过渡带冬季气候响应规律提供理论基础。A striking warming trend has triggered extreme weather and events in the regions worldwide.Snowfall is an important indicator of climate change,changes in snowfall at different levels reflect the integ-rated response of global warming to the trends in key climate variables and extreme events,and significant geo-graphical variation exists in the response pattern of snowfall in different levels across regions.Mountainous areas are highly sensitive to climate change.As an important geographical demarcation line between the north and south of China,the Qinling Mountains belongs to China’s snow-frequent belts,a sensitive area under cli-mate change.Based on the daily data from the 72 meteorological stations,we analyzed the spatio-temporal variation of heavy snowfall and light snowfall during November-March of the following year in the south and north of Qinling Mountains from 1970 to 2018,using the method of the wet bulb temperature dynamic threshold and trend analysis.Moreover,we assessed the relationship between the snowfall and temperature in three sub-regions(Guanzhong Plain,south slope of Qinling Mountains and Hanjiang Valley).The results show that:1)From 1970 to 2018,the number of rainless days increased,and the solid precipitation decreased obvi-ously during November-March of the following year in the south and north of the Qinling Mountains.The number of snowfall days decreased from 8.5%to 5.2%in the previous period after 1998,and the proportion of sleet days decreased from 1.2%to 0.6%.2)The response patterns of snowfall to climate change varies from snowfall in different levels.The snowfall amount and snowfall days of light snowfall decreased significantly,as well as intensity of light snowfall increased significantly.However,there was no clear linear increasing tendency in the snowfall amount,snowfall days and intensity of heavy snowfall,which indicates that the change of snowfall in the transition zone between north and south of China is dominated by the decrease of light snow.3)In terms of the response to

关 键 词：气候变化 强降雪 雨雪判别方法 秦岭南北 

分 类 号：P426.63[天文地球—大气科学及气象学]