Chinese Academy of Sciences Institute of Atmospheric Physics
利用北京闪电定位网(BLNET-Beijing Lightning Network)和SAFIR3000定位网7年共423次雷暴的闪电资料,并按照雷暴产生闪电多少划分为弱雷暴(≤1,000次)、强雷暴(＞1,000次和≤10,000次)和超强雷暴(＞10,000次),分析了北京地区的闪电时空分布特征及不同强度等级雷暴对闪电分布的贡献。北京年均总闪电密度最大值约15.4 flash.km-2.year-1,平均值约为1.9 flash.km-2.year-1,大于8 flash.km-2.year-1的闪电高值区基本分布在海拔高度200米等高线以下的平原地带。不同强度雷暴对总雷暴闪电总量贡献不同,弱雷暴(超强雷暴)次数多(少),产生的闪电少(多),超强雷暴和强雷暴产生的闪电分别占总雷暴闪电的37%、56%。不同强度雷暴对总雷暴闪电密度高值中心分布和日变化特征影响显著,昌平区东部、顺义区中东部和北京主城区是总雷暴闪电密度大于12 flash.km-2.year-1的三个主要高值区中心,前两个高值中心受强雷暴影响大,而主城区高值中心主要受超强雷暴影响。总雷暴晚上频繁的闪电活动主要受超强雷暴和强雷暴影响,这两类雷暴晚上闪电活动活跃,分别占各自总闪电的69%和65%,而弱雷暴闪电活动白天陡增很快,对总雷暴午后的闪电活动影响大。另外,不同下垫面条件闪电日变化差异大,山区最强的闪电活动出现在白天,午后闪电活动增强很快,主峰值出现在北京时间18:00,而平原最强的闪电活动发生在晚上,平原(山麓)的主峰值比山区推迟了约1.5小时(1小时)。
Based on the lightning data of 423 thunderstorms in the 7 years of BLNET(Beijing Lightning Network)and Surveillance et Alerte Foudre par Interometric Radioelectirque (SAFIR)-3000, and according to how many lightning flash is generated by thunderstorms, it is divided into weak thunderstorms (≤1,000 times) and strong thunderstorms (>1,000 times and ≤ 10,000 times) and super thunderstorms (>10,000 times), analyzed the spatial and temporal distribution characteristics of lightning flash in Beijing and the contribution of total thunderstorms with different intensity levels to lightning flash distribution. The average annual lightning flash density in Beijing is about 15.4 flash.km-2.year-1, and the average is about 1.9 flash.km-2.year-1.The lightning flash density high value area greater than 8 flash.km-2.year-1 is basically distributed in the plain area below the elevation of 200 meters above sea level. Different intensity thunderstorms contribute differently to the total thunderstorm lightning flash. The number of weak thunderstorms (super thunderstorms) is more (less), while the thunderstorms produce less lightning flash (more). The lightning flash generated by super thunderstorms and strong thunderstorms accounted for 37% and 56% of the total thunderstorm lightning flash, respectively. Different intensity thunderstorms have a significant impact on the distribution and daily variation characteristics of the total lightning flash intensity density of the total thunderstorm. The eastern part of Changping District, the central and eastern parts of Shunyi District and the main urban area of ??Beijing are the three thunderstorm lightning flash densities with a density greater than 12 flash.km-2.year-1. The first two high-value centers are greatly affected by strong thunderstorms, while the high-value centers in the main urban areas are mainly affected by super thunderstorms. The frequent lightning activities of thunderstorms in the evening are mainly affected by super thunderstorms and strong thunderstorms. These two types of thunderstorms were active at night, accounting for 69% and 65% of the total lightning flash, respectively, while the weak thunderstorm lightning activity increased rapidly during the day and greatly affected the lightning activity in the afternoon of the total thunderstorm. In addition, the difference in lightning conditions varies with different underlying conditions. The strongest lightning activity in the mountainous area occurs during the daytime. The lightning activity in the afternoon increases rapidly. The main peak appears at 18:00 in Beijing time, and the strongest lightning activity in the plain occurs at night. The main peak of the plain (Hawthorn) was delayed by about 1.5 hours (1 hour) than the mountainous area.