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Characteristics of the Two Active Stages of lightning Activity in Two Hailstorms

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Journal of Meteorological Research 2016年第2期30卷 265-281页

作者：徐爽郑栋王咏青胡鹏宇 School of Atmospheric Science Nanjing University of Information Science & Technology Shenyang Meteorological Administration State Key laboratory of Severe Weather Chinese Academy of Meteorological Sciences Liaoning Meteorological Disaster Monitoring and Early Warning Center

Two hailstorms that occurred in Beijing and Tianjin,respectively,are investigated,based mainly on the total lightning data observed by the System d＇Alerte Fondre par Interferometric Radioelecctrique（SAFIR3000）,the cloud-to-ground（CG） lightning data of a CG lightning location system,and the echo data of a Doppler *** hailstorms exhibited two lightning frequency peaks：the first was before the hailfall and the second was after the hailfall,with the second peak greater than the *** dominant polarity of the CG lightning was positive in the stage around the first frequency peak,but changed to negative in the stage around the second frequency *** evolution of radar echoes and the height distribution of lightning radiation sources are explored,revealing that both hailstorms had stronger convection and the main positive charge occurred at mid levels during the stage around the first frequency ***,whilst the Beijing hailstorm experienced the enhancement of convection,with the main positive charge at upper levels around the second frequency peak,the Tianjin hailstorm generated its second frequency peak during the period when the convection kept weakening and the main positive charge dropped to mid-lower *** evaluation of the radar parameters,we investigate the mechanisms responsible for the second stage of active lightning ***,the lightning activity exhibited a close relationship with radar echo parameters and *** jump signals were found before the hailfall and were associated with the change ratio of the 40-dBZ echo volume above the-15℃ level,which demonstrates the application value of lightning data in severe weather warning.

关键词： hailstorm total lightning electric structure

Comparison of six generalized linear models for occurrence of lightning-induced fires in northern Daxing'an Mountains,China

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Journal of Forestry Research 2016年第2期27卷 379-388页

作者： Futao Guo Guangyu Wang John L. Innes Zhihai Ma Aiqin Liu Yurui Lin College of Forestry Fujian Agriculture and Forestry University Sustainable Forest Management laboratory Faculty of Forestry University of British Columbia Department of Medicine University of Calgary College of Computer and Information Science Fujian Agriculture and Forestry University

The occurrence of lightning-induced forest fires during a time period is count data featuring over-dispersion （i.e., variance is larger than mean） and a high frequency of zero counts. In this study, we used six generalized linear models to examine the relationship between the occurrence of lightning-induced forest fires and meteorological factors in the Northern Daxing＇an Mountains of China. The six models included Poisson, negative binomial （NB）, zero- inflated Poisson （ZIP）, zero-inflated negative binomial （ZINB）, Poisson hurdle （PH）, and negative binomial hurdle （NBH） models. Goodness-of-fit was compared and tested among the six models using Akaike information criterion （AIC）, sum of squared errors, likelihood ratio test, and Vuong test. The predictive performance of the models was assessed and compared using independent validation data by the data-splitting method. Based on the model AIC, the ZINB model best fitted the fire occurrence data, followed by （in order of smaller AIC） NBH, ZIP, NB, PH, and Poisson models. The ZINB model was also best for pre- dicting either zero counts or positive counts （〉1）. The two Hurdle models （PH and NBH） were better than ZIP, Poisson, and NB models for predicting positive counts, but worse than these three models for predicting zero counts. Thus, the ZINB model was the first choice for modeling the occurrence of lightning-induced forest fires in this study, which implied that the excessive zero counts of lightning- induced fires came from both structure and sampling zeros.

关键词： Poisson Negative binomial (NB) Zero-inflated Poisson (ZIP) Zero-inflated negative binomial(ZINB) Poisson hurdle (PH) Negative binomial hurdle(NBH) Likelihood ratio test (LRT) Vuong test

Establishment of a Kind of Three-dimensional thunderstorm Cloud Electrification-Discharge Mode

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Meteorological and Environmental Research 2011年第8期2卷 5-8页

作者： YANG Hang KANG Gui-hong FENG Gui-li YANG Fan CHE Xiao-jun College of Electrical Engineering Chongqing UniversityChongqing 400044China Taian Meteorological Bureau in Shandong Province Taian 271000China lightning Protection Technology Center in Shandong Province Jinan 250031China

[Objective] The research aimed to study the establishment of a kind of three-dimensional thunderstorm cloud electrification-discharge mode.[Method] Based on a kind of three-dimensional strong convective cloud mode,several parameterization schemes of electrification-discharge mechanism which were mature and had experimental basis were coupled into the strong convective cloud *** three-dimensional strong convective mode could simulate electrification-discharge process,and the three-dimensional thunderstorm cloud electrification-discharge mode was established.[Result] By numerical simulation method,a kind of three-dimensional thunderstorm cloud electrification-discharge mode was *** mode not only could assess the relative importance of various kinds of electrification mechanisms under different environments,but also described formation of charge center and electrical field within the thunderstorm cloud,occurrence position,propagation process and influence on charge distribution of *** most important thing was that it could quantitatively describe the complicated relative relationships between power,microphysics and electric process in the evolution process of thunderstorm cloud.[Conclusion] The research provided powerful foundation for further studying the lightning characteristics of different thunderstorm clouds,the relationships between lightning characteristics and power,microphysical process,and deeply discussing the early-warning forecasting technology of thunderbolt activity.

关键词： thunderstorm Electrification-discharge Three-dimensional mode Establishment China

Projected Changes in NO_x Emissions from lightning as a Result of 2000–2050 Climate Change

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Atmospheric and Oceanic Science Letters 2013年第5期6卷 284-289页

作者： JIANG Hui LIAO Hong State Key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry(LAPC) Institute of Atmospheric Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

lightning is one of the most important natural sources of atmospheric *** authors investigate the2000–2050 changes in NOx emissions from lightning using the global three-dimensional Goddard Earth Observing System chemical transport model(GEOS-Chem)driven by meteorological fields from the Goddard Institute for Space Studies(GISS)general circulation model(GCM)*** changes in climate over 2000–2050are based on the Intergovernmental Panel on Climate Change(IPCC)A1B *** global NOx emission from lightning is simulated to be 4.8 Tg N in present day and to increase by about 16.7%over 2000–2050 as a result of the future climate *** largest present-day emissions and climate-induced changes are found in the upper troposphere in the *** in eastern China(20–55 N,98–125 E),NOx emissions from lighting is simulated to be 0.3 Tg N(6.3%of the global total emission)in present day and to increase by 26.7%over2000–*** simulated changes in NOx from lightening correspond well with the projected future changes in convective precipitation.

关键词： NOx lightning climate change

Evaluation of Horizontal Electric Field Under Different lightning Current Models by Perfect Ground Assumption

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高电压技术 2012年第8期38卷 2112-2116页

作者： LIANG Jianfeng LI Yanming State Key laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University Xi'an 710049 China

lightning electromagnetics can affect the reliability of the power system or communication ***,evaluation of electromagnetic fields generated by lightning return stroke is *** sommerfeld proposed a model to calculate the electromagnetic field,but it involved the time-consuming sommerfeld ***,perfect conductor ground assumption can account for fast calculation,thus this paper reviews the perfect ground equation for evaluation of lightning electromagnetic fields,presents three engineering lightning return stroke models,and calculates the horizontal electric field caused by three lightning return stroke *** to the results,the amplitude of lightning return stroke has a strong impact on horizontal electric fields,and the steepness of lightning return stroke influences the horizontal electric ***,the perfect ground method is faster than the sommerfeld integral method.

关键词：局部放电射频信号放电量高电压技术

Development characteristics of cloud-to-ground lightning with multiple grounding points

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Science China Earth Sciences 2018年第8期61卷 1127-1135页

作者： Bin FAN Ping YUAN Xuejuan WANG Yang ZHAO Jianyong CEN Yanling SU Key laboratory of Atomic and Molecular Physics and Functional Materials of Gansu Province College of Physics and Electronic Engineering Northwest Normal University School of Atmospheric Physics Nanjing University of Information Science and Technology College of Physics and Information Engineering Shanxi Normal University

Using the optical images of a cloud-to-ground lightning flash with multiple grounding points obtained by a highspeed video system in the Qinghai Province of China along with synchronous radiated electric field information, the propagation characteristic and the electric field change features of the leaders and the grounding behavior of discharge channels are *** addition, the two-dimensional velocity of the leader was estimated and its correlation with the time interval of the corresponding subsequent return stroke, and that with the peak current of return stroke are investigated. The results show that the average distance between the three obvious grounded points of the first return stroke channel is about 512.7 m, and the average time interval between the pulses of the corresponding electric field fast changes is 3.8 μs. Further, the average time interval between electric field pulses from the stepped leader is smaller than that of normal single grounding lightning. The observed lightning in our study has two main channels, namely the left and right channels. Based on our observations, it is clear that the dart leader comes close to the ground in case of the left channel after the first return stroke, but it fails to form a return ***, the right channel exhibits a relatively rare phenomenon in that the subsequent return stroke R2 occurred about 2.1 ms after the dart leader arrived at the ground, which was unusually long; this phenomenon might be attributed to the strong discharge of the first return stroke and insufficient charge accumulation near the grounded point in a timely manner. The two-dimensional velocities for the stepped leader of the two main channels are about 1.23×105 and 1.16×105 m s-1, respectively. A sub-branch of stepped leader for the left channel fails to reach the ground and develops into an attempt leader eventually; this might be attributed to the fact that the main branch connects considerably many sub-branches, which lea

关键词： Multiple grounding lightning High-speed camera Electric field changes Leader

Modeling of the Coupling of the lightning Shock Wave Flow Circuit in the High Voltage Electrical Network

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Energy and Power Engineering 2022年第8期14卷 404-419页

作者： Mwanamputu Mbwanzo Timothée Nsongo Pasi Bengi Masata Andre Flory Lidinga Mobonda Mathurin Gogom laboratory of Electrical Engineering Higher Institute of Applied Technique DC Kinshasa The Democratic Republic of the Congo laboratory of Physics Marien Ngouabi University at the Science and Technology Facility Brazzaville Republic of Congo laboratory of Electronics and Telecommunications Higher Institute of Applied Techniques DC Kinshasa The Democratic Republic of the Congo laboratory of Electrical Engineering Higher Institute of Applied Technique DC Boma The Democratic Republic of the Congo laboratory of Electrical and Electronic Engineering Marien Ngouabi University Brazzaville Republic of Congo

This article focuses on the aggression of lightning overload on the equipment of the electrical network of sites where storm activity is very dense;and the electrocution of people located in the direct environment of the high-voltage substation during the flow of lightning current to the ground through the ground socket. The modeling of the flow circuit of the shock wave consisting of guard wire, lightning arrester and ground socket couple to the transformer of the high voltage substations, thanks to the approach of a servo block, led to the synthesis of a PID regulator (corrector) whose action is to reject the effects of the overvoltage on the network equipment and to significantly reduce or even cancel the effects of the step or touch voltage due to the distribution of the potential around the ground socket;and thus improve the quality of service of the high-voltage transmission and distribution electricity network, especially in stormy times.

关键词： Modeling Coupling Flow Circuit Shock Wave lightning Electrical Network High Voltage

Case Studies of Sprite-producing and Non-sprite-producing Summer thunderstorms

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Advances in Atmospheric Sciences 2013年第6期30卷 1786-1808页

作者：杨静杨美荣刘超冯桂力 Key laboratory of Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Sate Key laboratory of Space Weather Chinese Academy of Sciences Henan Meteorological Bureau Shandong Research Institute of Meteorology

Three summer thunderstorms in the eastern region of China were analyzed in detail using multiple data, including Doppler radar, lightning location network, TRMM （Tropical Rainfall Measuring Mission）, MT- SAT （Multi-Function Transport Satellite） images, NCEP （National Centers for Environmental Prediction） Reanalysis, and radiosonde. Two of the three storms were sprite-producing and the other was non-sprite- producing. The two sprite-producing storms occurred on 1 2 August and 2~28 July 2007, producing 16 and one sprite, respectively. The non-sprite-producing storm occurred on 29-30 July 2007. The major ob- jective of the study was to try to find possible differences between sprite-producing and non-sprite producing storms using the multiple datasets. The results showed that the convection in the 1-2 August storm was the strongest compared with the other storms, and it produced the largest number of sprites. Precipitation ice, cloud ice and cloud water content in the convective regions in the 1-2 August storm were larger than in the other two storms, but the opposite was true in the weak convective regions. The storm microphysical prop- erties along lines through parent CG （cloud-to-ground lightning） locations showed no special characteristics related to sprites. The flash rate evolution in the 1-2 August storm provided additional confirmation that major sprite activity coincides with a rapid decrease in the negative CG flash rate. However, the evolution curve of the CG flash rate was erratic in the sprite-producing storm on 27-28 July, which was significantly different from that in the 1 2 August storm. The average positive CG peak current in sprite-producing storms was larger than that in the non-sprite-producing one.

关键词： sprite Doppler radar TRMM lightning thunderstorm

Effectiveness of lightning Protection Devices

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高电压技术 2008年第12期34卷 2517-2522页

作者： S. Grzybowski T. Disyadej S. Mallick High Voltage laboratory Department of Electrical and Computer Engineering Mississippi State University Mississippi State MS 39762 USA

In addition to the conventional Franklin Rod,many non-conventional air terminals are being used as lightning protection *** cited in previous works,these non-conventional devices emit space charge in the vicinity of the terminals during the process of lightning stroke.A number of factors affect the performance of these lightning protection devices,among them are geometry and dimension of the devices,location of the device above the ground,height of the cloud above the ground,and polarity of the lightning *** performance of these lightning protection devices has been a topic of discussion by researchers for many *** studies focused on the magnitude of emission current from these devices as a criterion to evaluate their *** critical flashover voltage(CFO)between the devices and a metal screen simulating cloud can also be used as another criterion to evaluate the performance of the *** measurements were conducted in controlled conditions on different types of lightning protection devices to compare their *** different types of devices were used in the present study:Franklin Rod,TerraStat models TS 100,TS 400,and Spline Ball *** study focused on the CFO voltage of the air gap between devices and the metal *** CFO voltage was evaluated using standard switching and lightning *** measurements were recorded for positive as well as negative *** air gap between the devices and metal screen was selected at 2 m and 3 *** results obtained provide a better understanding of the electrical performance of lightning protection devices.

关键词：雷电保护装置有效性接线端电流