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Atmospheric electricity research has been conducted actively in China, having profited from the development and application of high temporal and spatial resolution lightning detection and location technologies. This paper reviews the scientific advances made in the field of atmospheric electricity in China from 2011 to 2018, covering the following five aspects:(1)lightning detection and location techniques;(2) discharge processes and parameters associated with rocket-triggered lightning;(3) physical processes in natural lightning and attachment to the ground;(4) lightning activities and charge structure in different thunderstorms; and(5) effects of thunderstorms on the upper atmosphere. In addition, some outstanding questions for future research are outlined. 相似文献
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A review of atmospheric electricity research in China 总被引:1,自引:0,他引:1
QIE Xiushu ZHANG Yijun YUAN Tie ZHANG Qilin ZHANG Tinglong ZHU Baoyou LU Weitao MA Ming YANG Jing ZHOU Yunjun FENG Guili 《大气科学进展》2015,32(2):169-191
The importance of atmospheric electricity research has been increasingly recognized in recent decades. Research on atmospheric electricity has been actively conducted since the 1980 s in China. Lightning physics and its effects, as important branches of atmospheric electricity, have received more attention because of their significance both in scientific research and lightning protection applications. This paper reviews atmospheric electricity research based primarily on ground-based field experiments at different regions in China in the last decade. The results described in this review include physics and effects of lightning, rocket-triggered lightning and its physical processes of discharge, thunderstorm electricity on the Tibetan Plateau and its surrounding areas, lightning activity associated with severe convective storms, the effect and response of lightning to climate change, numerical simulation of thunderstorm electrification and lightning discharge, lightning detection and location techniques, and transient luminous events above thunderstorms. 相似文献
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Lightning meteorology focuses on investigating the lightning activities in different types of convective weather systems and the relationship of lightning to the dynamic and microphysical processes in thunder- storms. With the development and application of advanced lightning detection and location technologies, lightning meteorology has been developed into an important interdiscipline between atmospheric electricity and meteorology. This paper mainly reviews the advances of lightning meteorology research in recent years in China from the following five aspects: 1) development of advanced lightning location technology, 2) char- acteristics of lightning activity in different convective systems, 3) relationship of lightning to the dynamic and microphysical processes in thunderstorms, 4) charge structure of thunderstorms, and 5) lightning data assimilation techniques and application to severe weather forecasting. In addition, some important aspects on future research of the lightning meteorology are proposed. 相似文献
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利用卷积神经网络和门控循环单元(Gated recurrent units )神经网络,基于雷达反射率因子和雷电定位数据开展了雷电预报研究。首先构建了引用注意力机制的基于卷积神经网络和门控循环单元神经网络的深度学习模型(Attention ConvGRU);然后将雷达反射率因子数据和对应时间段(6 min)的雷电定位数据处理成图像数据后输入深度学习模型,训练出可预报雷电的模型,包括3种模型:单雷电数据模型、单雷达数据模型和雷电〖CD*2〗雷达双数据模型;最后开展了预报试验和定量评估。综合评估表明,本文建立的雷电预报模型综合预报准确率达到96.74%,虚警率35.83%,关键成功指数(Critical Success Index, CSI)为0.2072。个例分析表明,预报模型对于具有明显移动趋势的雷暴过程(A类雷暴)的预报效果优于不具有明显移动趋势的雷暴过程(B类雷暴),且随着B类雷暴强度减弱模型预报能力逐渐减弱。 相似文献
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分析了2019年夏季在广州从化人工引雷试验场获取的14次人工触发闪电通道底部电流数据,以有无回击(RS)和初始连续电流(ICC)持续时间长短2个标准对数据进行分类,研究不同触发闪电和不同放电阶段的差异和规律。研究表明:相比无回击的触发闪电,产生回击的触发闪电具有更大的先驱放电脉冲(PCP)及初始先驱放电脉冲(IPCP)的平均峰值电流、更多的IPCP总体转移电荷量、更大的ICC平均电流和总体转移电荷量以及更长的ICC持续时间;初始连续电流持续时间是回击平均峰值电流大小、首次继后回击转移电荷量大小和首次继后回击峰值电流大小的重要影响因素,且长初始连续电流的触发闪电对应的PCP及IPCP平均峰值电流也更大、平均转移电荷量也更多;PCP和IPCP平均峰值电流与ICC持续时间相关性最强,是决定ICC放电持续时间的重要因素,未能产生初始连续电流的PCP脉冲簇其平均转移电荷量小于初始先驱放电脉冲簇,其转化的关键阈值之一是平均转移电荷量大于25.91μC。 相似文献
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云下部正电荷区与负地闪预击穿过程 总被引:1,自引:0,他引:1
三维雷电观测系统LMA(Lightning Mapping Array)是最近发展起来的基于GPS时钟同步的闪电VHF辐射源到达时间差(TOA)定位技术,能以很高的时间分辨率(50 ns)和空间定位精度(50—100 m)展现闪电放电发展过程的三维时空分布,揭示雷暴中电荷结构及其与放电过程的关系。文中利用三维雷电VHF辐射源观测资料分析了负地闪预击穿过程的时空分布特征,讨论了云下部正电荷区对负地闪发生的影响,其结果表明在首次回击之前存在长时间预击穿过程的负地闪中,预击穿过程是云中部负电荷区与下部正电荷区之间的一种云内放电过程,闪电起始于云中部负电荷区,然后向下发展传输,进入正电荷区后闪电通道在云下部正电荷区水平发展,其放电特征与反极性云闪放电一致,云内放电过程最后阶段的K型击穿激发了地闪的梯级先导,梯级先导穿过云下部正电荷区向下发展传输。云下部正电荷的存在是导致负地闪首次回击之前存在长时间云内预击穿过程的主要原因。 相似文献
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针对2009—2013年浙江省气象部门和电力部门闪电定位系统 (lightning location system, LLS) 监测的地闪 (cloud-to-ground lightning, CG lightning) 数据,从时空分布及探测效率等方面对两者进行对比。结果表明:电力部门LLS监测的年平均地闪频次稳定大于气象部门LLS监测的年平均地闪频次。从空间分布看,沿海平原和金衢盆地等平原地带,两者的地闪密度相近;在杭州和衢州交界地区,气象部门LLS监测的地闪密度稳定大于电力的地闪密度;在其他地区 (如浙西北、浙中南部和浙南等大部分地区),电力部门LLS监测的地闪密度稳定大于气象部门LLS监测的地闪密度。利用雷暴日数对两者的探测能力对比可知,气象部门LLS对一些较弱雷暴天气过程中的地闪有漏测可能。利用雷击跳闸记录对比分析,电力部门LLS逐年探测效率稳定高于气象部门LLS的探测效率,两者相差约6%。 相似文献
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该文选取北京地区2006年夏季的18次雷暴过程,利用SAFIR3000三维闪电定位系统观测到的总闪数据,分析了闪电与雷达反演的对流活动区降水量和对流活动区面积的相关关系,结果表明:北京地区的雷暴活动中,单个闪电所表征的降水量的范围在0.86×10~7~6.57×10~7kg/fl之间,平均值为2.65×10~7kg/fl;闪电活动与对流活动区降水量的线性相关关系显著,相关系数达到0.826;闪电活动与对流活动区面积也具有显著的线性关系,相关性系数达到0.846。文中给出了基于6 min闪电频次估算6 min对流降水量以及对流活动区面积的拟合方程。分析还发现,总闪活动与降水的关系要明显好于地闪,总闪信息的应用极大提高了分析结果的质量和可信性,分析结果对于利用闪电信息估测降水具有参考意义。 相似文献
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利用M-LDARS闪电定位系统对北京及其周边地区1995~1997年6~9月的闪电观测数据, 分析闪电活动的时空分布特征。结果表明:闪电活动在时间分布上存在两个峰值时段, 13 :00~21:00和23:00~次日05 :00。通过对总地闪、分时段及峰值时段的地闪密度分析, 发现北京及周边地区闪电活动有几个明显的集中区域, 地闪高密度区主要出现在下垫面为山脉和水体的地方, 闪电活动与下垫面的水汽条件关系密切, 且正、负地闪的空间分布也呈现较大差异, 表明雷暴云的电荷结构存在一定差异。 相似文献
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LU Weitao ZHANG Yijun ZHOU Xiuji MENG Qing ZHENG Dong MA Ming WANG Fei CHEN Shaodong QIE Xiushu 《Acta Meteorologica Sinica》2008,22(3):362-374
A comparison is made of the high-speed (2000 fps) lightning between two techniques. The analysis shows (UPL) in altitude-triggered negative lightning (ATNL) photographic records in rocket-triggered negative that: the initial speed of upward positive leader is about one order of magnitude less than that in classically triggered negative lightning (CTNL), while the triggering height of ATNL is higher than that of CTNL; the afterglow time of metal-vaporized part of the lightning channel can endure for about 160-170 ms, thus the luminosity of the air-ionized part can reflect the characteristics of the current in the lightning channel better than that of the metal-vaporized part. According to the different characteristics of the luminosity change of the lightning channel, together with the observation of the electric field changes, three kinds of processes after return-stroke (RS) can be distinguished: the continuous decaying type without M component, the isolated type and the continuing type with M component, corresponding to different wave shapes of the continuous current. The geometric mean of the interval of RS with M component is 77 ms, longer than that (37 ms) of RS without M component. And the initial continuous current (ICC) with M component also has a longer duration compared to the ICC without M component. The distinction in the relative luminosity between the lightning channel before RS and that before M component is obvious: the former is very weak or even cannot be observed, while the latter is still considerably luminous. 相似文献
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基于2014—2015年5—9月西藏那曲地区多普勒天气雷达数据,结合地闪观测数据,识别雷暴单体样本,统计分析了地闪位置附近的雷达回波分布特征,并研究了高原雷暴的雷达参量与地闪频次的相关关系。结果表明:那曲地区地闪发生位置附近的雷达最大反射率因子呈正态分布,峰值分布区间集中于34~41 dBZ。发生地闪位置附近的20 dBZ回波顶主要集中于11~15 km高度,30 dBZ回波顶高分布的峰值区间则为8.5~12 km。分析表明:表征局地雷暴对流发展强度的雷达参量与地闪频次之间一对一的相关关系较差,但相关性随地闪频次增加而增强。基于雷达参量分段统计得到的对应分段平均地闪频次与雷达参量之间表现出较强相关关系,体现了宏观上闪电活动强度与雷暴发展强度之间的正向关系。其中,基于原始数值进行区间划分的强回波(组合反射率因子不小于30 dBZ)面积与平均地闪频次的线性相关系数达0.75,基于对数数值区间划分的7~11 km累积可降冰含量的对数值和地闪频次的线性相关系数达0.95。文中对比了多个雷达参量和地闪频次线性拟合与幂函数拟合结果,整体上幂函数拟合略好于线性拟合。 相似文献
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阿吉古丽?沙依提 《沙漠与绿洲气象(新疆气象)》2012,6(3):62-65
利用塔克拉玛干沙漠腹地的塔中气象站1996-2010年地面观测资料对该地区的雷暴和闪电特征进行了分析。结果表明:塔中地区年平均雷暴日数为9.3d,年平均闪电日数为2.7d。塔中地区4月开始出现雷暴和闪电,7月达到最高值,10月至翌年3月之间无雷暴和闪电发生,塔中地区雷暴平均初日为6月1日,平均终日为8月5日。塔中地区雷暴多出现在午后至凌晨,并以30min以内的短时雷暴为主,雷暴出现的最多方位是W和N。 相似文献
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基于浙江省ADTD二维闪电定位系统监测的近11 a(2007—2017)地闪数据,采用密度极大值快速搜索聚类算法和Kalman滤波算法实现对雷暴的识别及其路径的追踪,并探讨大范围雷暴过程的时空分布特征.结果表明:该方法能够有效对浙江省各类雷暴的识别追踪,共筛选出261条雷暴过程的路径,其存在明显的年变化和年际变化,年路... 相似文献
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Abhay SRIVASTAVA Dongxia LIU Chen XU Shanfeng YUAN Dongfang WANG Ogunsua BABALOLA Zhuling SUN Zhixiong CHEN Hongbo ZHANG 《大气科学进展》2022,39(1):178-188
A thunderstorm tracking algorithm is proposed to nowcast the possibility of lightning activity over an area of concern by using the total lightning data and neighborhood technique.The lightning radiation sources observed from the Beijing Lightning Network(BLNET)were used to obtain information about the thunderstorm cells,which are significantly valuable in real-time.The boundaries of thunderstorm cells were obtained through the neighborhood technique.After smoothing,these boundaries were used to track the movement of thunderstorms and then extrapolated to nowcast the lightning approaching in an area of concern.The algorithm can deliver creditable results prior to a thunderstorm arriving at the area of concern,with accuracies of 63%,80%,and 91%for lead times of 30,15,and 5 minutes,respectively.The real-time observations of total lightning appear to be significant for thunderstorm tracking and lightning nowcasting,as total lightning tracking could help to fill the observational gaps in radar reflectivity due to the attenuation by hills or other obstacles.The lightning data used in the algorithm performs well in tracking the active thunderstorm cells associated with lightning activities. 相似文献