基于雷达观测的福建暖季对流天气特征分析  

Analysis on weather characteristics of convection during the warm season over Fujian Province based on radar observations

作　　者：冯晋勤 赖巧珍 蔡菁 FENG Jinqin;LAI Qiaozhen;CAI Jing(Longyan Meteorological Bureau of Fujian Province,Longyan 364000,Fujian,China;Fujian Key Laboratory of Severe Weather,Fuzhou 350001,China)

机构地区：[1]福建省龙岩市气象局,福建龙岩364000 [2]福建省灾害天气重点实验室,福建福州350001

出　　处：《干旱气象》2024年第6期865-877,共13页Journal of Arid Meteorology

基　　金：福建省自然科学基金项目(2019J01099、2020J01099、2021J01450和2023J01185);福建省气象局开放式基金项目(2018K01)共同资助。

摘　　要：研究福建暖季对流系统分布特征对对流天气的预报预警有重要参考意义。利用福建建阳、龙岩、长乐、厦门4部天气雷达2008—2017年资料识别暖季(4—8月)对流,分区域分析对流的空间、时间和垂直结构,以及不同面积和伸展高度的对流系统的空间和日变化特征。结果表明:福建暖季的5—6和8月为对流活动高峰期;暖季对流具有明显的区域分布特征,4—6月对流高发区位于内陆,7—8月位于沿海山脉一带;6—8月以中深对流为主,4月以大面积对流为主,5—6月以中等和大面积对流为主,7—8月以中等和小面积对流为主。对流的垂直结构月分布有差异,中等强度对流的回波强度7—8月最强,西北部回波发展高度最高。对流频数存在明显的日变化,对流常发生于15:00—16:00(北京时),7—8月以午后单峰为主,4—5月呈双峰或多峰特征。面积越大的对流系统频数峰值出现越迟,中深和深对流午后峰值明显。5—6月内陆夜间到清晨对流高发由边界层惯性振荡形成风场的日变化及其扰动风与地形相互作用造成,8月沿海山脉对流高发原因是午后沿海山脉处于近地层加热中心、风场辐合和能量大值区中。Studying the distribution of convection during the warm season over Fujian Province has important significance for forecast⁃ing and warning of convective weather.Based on four weather radars data of Jianyan,Longyan,Changle and Xiamen in Fujian from 2008 to 2017,convection in warm season(from April to August)was identified,and the spatial-temporal and vertical structure of con⁃vection,as well as spatial and diurnal variation characteristics of convective systems with different areas and extension heights were analyzed.The results show that the peak period of convective activity is from May to June and August during the warm season in Fujian.The convection in warm season has obvious regional distribution characteristics,the high incidence area is located in the inland from April to June,and from July to August it is in the coastal mountains.From June to August,it is dominated by medium-deep convection,and it is dominated by large area convection in April,and from May to June and from July to August it is dominated by medium and large area convection,medium and small area convection,respectively.The monthly distribution of vertical structure of convection is different.The echo intensity of moderate convection is the maximum from July to August.The echo extension height in northwest Fujian is the highest.There is obvious diurnal variation of convective frequency.Convection often occurs from 15:00 to16:00(BST),and it is the mainly single peak in the afternoon from July to August,while from April to May there are bimodal or multi-peak.The frequency peaks of convective systems with larger area appear later,and the mid-deep and deep convective peaks are obvious in the afternoon.From May to June,the high incidence of inland convection from night to morning was caused by the diurnal variation of the wind field formed by the inertia oscillation of the boundary layer and the interaction between the disturbing wind and terrain.In August,the high incidence of convection in coastal mountains was caused by the fact that the

关 键 词：天气雷达 福建 暖季 对流 时空特征 

分 类 号：P458.121.1[天文地球—大气科学及气象学]