2013年宁波地区一次海风锋对雷暴过程影响分析及数值模拟  

Analysis on the sea breeze front effect on thunderstorm process in Ningbo area in 2013 and its numerical simulation

作　　者：吴福浪 汤剑平[1,3] 刘建勇 WU Fulang;TANG Jianping;LIU Jianyong(Key Laboratory of Mesoseale Severe Weather/Ministry of Education,Nanjing University,Nanjing 210093,China;State Key Laboratory of Disaster Weather,Chinese Academy of Meteorological Sciences,Belting 100000,China;The Meteorological Station of China Civil Aviation Air Traffw Management Station of Ningbo,Zlwjiang Ningbo 315000,China;Meteorological Bureau of Ningbo,Zhejiang Ningbo 315000,China)

机构地区：[1]南京大学中尺度灾害性天气教育部重点实验室,南京210093 [2]中国民用航空宁波空中交通管理站气象台,浙江宁波315000 [3]中国气象科学研究院灾害天气国家重点实验室,北京100000 [4]宁波市气象局,浙江宁波315000

出　　处：《气象科学》2018年第4期442-452,共11页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(41375075);中国气象科学研究院灾害天气国家重点实验室开放课题(2015LASW-A04)

摘　　要：利用浙江省常规气象站观测资料、地面自动站加密资料、新一代多普勒天气雷达资料、NCEP GFS分析资料以及WRF中尺度模式,对2013年7月29日发生在宁波市地区的一个局地强雷暴天气过程进行了诊断分析和数值模拟。通过对天气环流和数值模拟结果的分析发现:本次强雷暴过程发生在较稳定的大气背景下,主要影响系统是中尺度辐合线海风锋;多普勒雷达出现弱窄带回波时,对应中尺度辐合线海风锋;海风锋向内陆推进时,对应站点温度降低、湿度增大。WRF模式能较好地模拟出此次雷暴过程以及宁波地区低层海风锋环流,高空回流随时间和空间的演变特征;海风锋的锋生造成的地转强迫促使次级环流加强,在东西风辐合线西侧有垂直上升运动出现;通过与敏感试验的对比可知,海陆热力差异是影响雷暴降水强度、海风锋水平垂直环流的重要因素。The effect of sea breeze front on a severe local thunderstorm occurring on July 29,2013 in Ningbo was studied in this paper. Diagnostic analysis was performed using the observational data from the conventional meteorological stations and the encrypted data from the ground automatic weather stations in Zhejiang Province,the new generation Doppler weather radar,and the NCEP GFS analysis data. WRF was adopted to carry out numerical simulations. Analysis of observational data shows that the severe thunderstorm occurs in a stable atmosphere,and the sea breeze front associated with mesoscale convergence line plays the most important role. The mesoscale sea breeze front in the boundary layer can be identified by the narrow-band echo in the Doppler radar. As the sea breeze front advances inland,the temperature falls and the humidity rises,which can be captured by the meteorological stations. The numerical simulation withWRF can well reproduce this severe thunderstorm process, and capture the spatial and temporal characteristics of low-level sea breeze front circulation as well as the high-level backflow in Ningbo.Geostrophic forcing associated with the sea breeze front frontogenesis strengthens the secondary circulation,favoring ascending motions in the convergence line of the east and west wind. Sensitivity simulation suggests that the sea-land thermal contrast is an important factor that influences the precipitation intensity and the vertical and horizontal circulation of sea breeze front during the thunderstorm.

关 键 词：雷暴 海风锋 数值模拟 

分 类 号：P446[天文地球—大气科学及气象学]