舟山绿色石化基地雷暴天气的时空分布及物理量统计特征分析  

Spatio-temporal Distribution and Environmental Properties of Thunderstorms in Zhoushan Green Petrochemical Base

作　　者：方言 刘菡 朱思瑜 徐哲永 马恩点 Fang Yan;Liu Han;Zhu Siyu;Xu Zheyong;Ma Endian(Zhoushan Meteorological Office,Zhoushan 316021,Zhejiang,China;Zhoushan Meteorological Safety Technology Center,Zhoushan 316021,Zhejiang,China)

机构地区：[1]舟山市气象局,浙江舟山316021 [2]舟山市气象安全技术中心,浙江舟山316021

出　　处：《科技通报》2024年第4期26-32,38,共8页Bulletin of Science and Technology

基　　金：浙江省气象局预报员专项(2021YBY15);舟山科技计划项目(2022C31073)。

摘　　要：本文利用舟山地区的雷暴观测资料、闪电定位资料、MICAPS(meteorology information comprehensive analysis process system)常规气象资料等,对舟山绿色石化基地地区2017—2021年雷暴天气时空分布特征及分类特征进行统计分析。结果表明:2017—2021年该地区年均地闪密度约为1.9~2.1次/km^(2)·a;雷暴天气在2019年后逐年增加。月雷暴分布呈双峰型,8月雷暴最多,月均雷暴日为7.2 d。5年内夏季发生雷暴的次数占全年的58%。从热动力学结构特征将该地区的雷暴天气分为5类:准正压类、斜压锋生类、暖平流强迫类、冷平流强迫类和高架雷暴类,依次占比51%、19%、16%、10%和4%;夏季以准正压类占主导,春季多为斜压锋生类。通过对NCEP 1°×1°物理量再分析场对雷暴过程的指示性进行统计分析,结果显示:CAPE、K指数、LI指数、PWAT是判断夏、秋两季出现强对流的敏感性指标,而春季仅有K指数有较好的指示意义;T(850~500 hPa)在23~24℃,是判断是否出现雷暴的有利指标;高低空垂直风切变(春季:14.61 s^(-1)、夏季:6.89 s^(-1)、秋季:8.30 s^(-1))是指导不同季节是否发生雷暴最有区分度的判据。This study analyzed the temporal and spatial distributions of thunderstorms in Zhoushan green Petrochemical base from 2017—2021,based on the thunderstorm observation data,lightning positioning data and MICAPS(meteo-rology information comprehensive analysis process system)conventional meteorological data in Zhoushan.The results showed that the average annual ightning density in this area is about 1.9-2.1 times(km^(2)·a)^(-1) during 2017—2021;After the year of 2019,thunderstorm weather had an obvious increasing trend.The monthly variation of thunderstorm shows a double peak structure with the major peak in August.And the average monthly thunderstorm day is 7.2 days.The occurrence frequency of thunderstorm days in summer(June,July,and August)accounts for 58%of the total thunderstorm days.The synoptic situations associated with thunderstorms are divided into five types:quasi-barotropic category,baroclinic frontogenesis category,cold advection forcing category,warm advection forcing category,and el-evated thunderstorm category.They contribute 51%,19%,16%,10%and 4%to the total occurrence,respectively.The quasi-barotropic category and baroclinic frontogenesis category are the dominant type in summer and spring,re-spectively.Further analysis of environmental conditions associated with thunderstorms suggest that CAPE,K index,LI index,and PWAT are sensitive indicators to judge the occurrence of thunderstorms in summer and autumn,while in spring,only K index has a good indication.The temperature difference between 850 hPa and 500 hPa is around 23-24℃,which is a favorable indicator to judge whether thunderstorm occurs.Additionally,the vertical wind shear be-tween 850 hPa and 500 hPa(14.61 s^(-1) in spring,6.89 s^(-1) in summer and 8.30 s^(-1) in autumn)is the best indicator of whether thunderstorms are occurring in different seasons.

关 键 词：舟山绿色石化基地 雷暴 时空分布 物理量 

分 类 号：P457.9[天文地球—大气科学及气象学]