登陆广东地区强台风及超强台风闪电活动特征研究
Lightning Activity Characteristics of Severe Typhoon and Super Typhoon Landing in Guangdong Province
中文摘要：
利用广东闪电定位监测资料、广东台风路径实时发布系统的热带气旋（TC）强度和路径资料，分析了2008—2018年登陆广东地区的7个强台风和1个超强台风的闪电活动时空分布特征及其与TC强度变化的关系。结果表明：TC闪电活动的增减与TC登陆与否没有直接关系，TC闪电活动日变化呈“单峰”分布，峰值出现在17: 00（北京时，下同），谷值出现在07: 00；TC径向闪电密度呈“三圈”结构分布，内核区和外雨带闪电活动活跃，内雨带闪电活动不活跃，TC不同区域微物理特征和上升气流的差异是导致TC闪电活动呈现“三圈”结构的原因；无论在TC登陆前或是登陆后，外雨带闪电活动均占绝对优势，TC在登陆后闪电活动有向TC中心内收的趋势；TC闪电活动在空间分布上呈现非对称结构；TC闪电活动强弱与发生闪电时的TC强度等级不存在明显关系，并不是TC强度越强，闪电越活跃；闪电活动易发生在台风（TY）阶段，随着TC强度的增强，闪电活动逐渐减弱；内核区随着TC强度的增强，闪电活动存在爆发，TC减弱时闪电活动出现递减，表明内核区闪电活动对TC强度变化具有较好的指示意义；TC减弱期内核区和内雨带闪电活动最强，TC增强阶段外雨带闪电活动最活跃。
中文关键词：
台风，闪电，强度变化，闪电密度
KeyWords：
typhoon, lightning, intensity variation, lightning density
Abstract：
Based on the cloud-to-ground (CG) lighting location data as well as tropical cyclone (TC) intensity and path data from Guangdong typhoon real-time release system, we analyzed the spatiotemporal distribution characteristics of lightning activity and its relationship with TC intensity changes in seven severe typhoons and one super typhoon that landed in Guangdong from 2008 to 2018. The results show that the increase or decrease of TC lightning activity is not directly related to whether the TC makes landfall or not. The daily variation of TC lightning activity presents a single peak distribution, with a peak at 17: 00 BT and a valley at 07: 00 BT. TC exhibits three distinct circles of radial lightning density, with active lightning in the inner core and outer rainband, but inactive lightning in the inner rainband. The differences in microphysical characteristics and updrafts within different regions of TC are responsible for the “three-circle” structure of TC lightning activity. Whether before or after TC landing, the outer rainband has an overwhelming majority of lightning, and there is a trend for lightning activity to converge towards the center of the TC after landing. TC lightning activity displays a spatially asymmetric distribution. There is no significant correlation between the intensity of TC lightning activity and the intensity level of the TC at the time of lightning occurrence. It is not the case that the stronger the TC intensity, the more active the lightning. Lightning activity is most likely to occur during the typhoon stage, and as the intensity of the TC increases, the lightning activity gradually weakens. In the inner core, lightning activity surges with the intensification of the TC, and the weakening of the TC is accompanied with the decrease of lightning activity, indicating that lightning activity in the inner core has good indicative significance for changes in TC intensity. During the weakening period of the TC, the inner core and inner rainband experience the strongest lightning activity, while during the intensification period of the TC, lightning activity is most active in the outer rainband.