基于高精度观测资料的2009-2019年祁连山地区降水特征分析  

Analysis of precipitation characteristics in Qilian Mountains from 2009 to 2019 based on high precision observation data

作　　者：蒋强 魏林波[1,2] 李艳 胡小玲[1] 刘子奇 黄万龙 JIANG Qiang;WEI Lin-bo;LI Yan;HU Xiao-ling;LIU Zi-qi;HUANG Wan-long(Key Laboratory of Arid Climatic Changes and Disaster Reduction of Gansu Province,College of Atmospheric Sciences,Lanzhou University,Lanzhou 730000,China;Key Laboratory of Cloud Physical Environment,China Meteorological Administration,Beijing 100081,China)

机构地区：[1]兰州大学大气科学学院甘肃省干旱气候变化与减灾重点实验室,兰州730000 [2]中国气象局云雾物理环境重点实验室,北京100081

出　　处：《兰州大学学报（自然科学版）》2022年第1期89-98,共10页Journal of Lanzhou University(Natural Sciences)

基　　金：国家重点研发计划项目(2017YFC1501805);中国气象科学研究院西北区域人工影响天气能力建设项目(ZQC-R18208);中央高校基本科研业务费专项资金项目(lzujbky-2017-61)。

摘　　要：通过高精度的观测资料结合NCEP/NCAR再分析资料,对祁连山及周边地区降水的时空分布特征进行分析,发现整体呈东多西少、南多北少的空间分布特征.湿季(5-9月)总降水量占全年降水量的90%以上, 7、8月是降水最多的时段.对降水周期进行小波分析发现,“准单周振荡”信号在整个湿季是最显著的;“准双周振荡”信号在7、8月是最主要的.祁连山地区存在显著的午后、夜间降水特征,且山南降水多于山北.利用双线性插值的方法对祁连山的东、中段进行剖面分析,挑选区域性降水个例,合成分析降水的大气环流场及水汽场,发现祁连山地区降水偏多的大气环流特征主要为中高纬度“一槽一脊”、中纬度巴尔喀什湖大槽、低纬度地区孟加拉湾气旋和稳定的副热带高压.有利的地形、更好的水汽条件及西北涡的存在是7、8月祁连山山南降水普遍多于山北的原因.Based on the high-precision observation data and NCEP/NCAR reanalysis data, we analyzed the spatial and temporal distribution characteristics of precipitation in Qilian Mountain and surrounding areas, showing that the spatial distribution of precipitation in the whole region were more in the east and less in the west, more in the south and less in the north. The precipitation in the wet season(May to September) accounted for more than 90% of the annual rainfall, and July and August were the periods with the most precipitation of all the months of a year. The wavelet analysis of the wet season precipitation cycle showed that the ’quasi-monocycle oscillation’ signal was the most significant in the whole wet season,and ’quasi-biweekly oscillation’ signal the most significant in July and August. The precipitation in the afternoon and night was significant in Qilian Mountains, and the precipitation in the south is higher than that in the north. A bilinear interpolation method was used to analyze the profile of the east and middle sections of Qilian Mountains, and individual cases of regional precipitation selected to synthesize and analyze the atmospheric circulation field and water vapor field. It was found that the atmospheric circulation characteristics of more precipitation in Qilian Mountains were mainly "one trough and one ridge" in the middle and high latitudes, the Balkhash Lake trough in the middle latitude, the bay of Bengal cyclone in the low latitude area and the stable subtropical high. On the basis of the above conditions, favorable topography, better water vapor conditions and the existence of a northwest vortex were the reasons that the precipitation in the south of Qilian Mountains was more than that in the north in July and August.

关 键 词：祁连山 时空分布特征 小波分析 合成分析 

分 类 号：P426[天文地球—大气科学及气象学]