INVESTIGATION OF RADAR AND ELECTRICAL CHARACTERISTICS OF THUNDERCLOUDS SEEDED WITH A GLACIOGENIC REAGENT IN KARNATAKA, INDIA

2021 ◽  
pp. 112-122
Author(s):  
A.A. SIN'KEVICH ◽  
◽  
B. BOE ◽  
S. PAWAR ◽  
YU. P. MIKHAILOVSKII ◽  
...  
Keyword(s):  
Network Data ◽  
Lightning Flash ◽  
Electrical Characteristics ◽  
North Caucasus ◽  
Flash Rate ◽  
Convective Clouds ◽  
The North ◽  
Lightning Detection ◽  
Karnataka State ◽  
Order Of Magnitude

Characteristics of developing convective clouds (Cu) in Karnataka state (India) during the thunderstorm formation are analyzed using weather radar and lightning detection network data. It is noted that radar characteristics of Cu which produced lightning, exceed those where lightning does not form. The study has shown that the number of negative cloud-to-ground strokes exceeds the number of positive ones by an order of magnitude. The radar characteristics of clouds in India and the North Caucasus are compared. Significant differences in lightning flash rates over the mentioned regions are registered. A low correlation is found between the supercooled volume and the flash rate of negative lightning. The paper also presents the results of studying the dynamic characteristics of four Cu seeded with a glaciogenic reagent. The thunderstorm risk is estimated for the clouds. It is shown that the seeding increases a probability of lightning events.

scholarly journals Modeling the Flash Rate of Thunderstorms. Part II: Implementation

2011 ◽  
Vol 139 (10) ◽  
pp. 3112-3124 ◽  
Author(s):  
Johannes M. L. Dahl ◽  
Hartmut Höller ◽  
Ulrich Schumann
Keyword(s):  
Small Scale ◽  
Lightning Flash ◽  
New Approach ◽  
Southern Germany ◽  
Flash Rate ◽  
Convective Clouds ◽  
Direct Observations ◽  
Scale Modeling ◽  
Lightning Detection ◽  
Total Lightning

Abstract In Part I of this two-part paper a new method of predicting the total lightning flash rate in thunderstorms was introduced. In this paper, the implementation of this method into the convection-permitting Consortium for Small Scale Modeling (COSMO) model is presented. The new approach is based on a simple theoretical model that consists of a dipole charge structure, which is maintained by a generator current and discharged by lightning and, to a small extent, by a leakage current. This approach yields a set of four predictor variables, which are not amenable to direct observations and consequently need to be parameterized (Part I). Using an algorithm that identifies thunderstorm cells and their properties, this approach is applied to determine the flash frequency of every thunderstorm cell in the model domain. With this information, the number of flashes that are accumulated by each cell and during the interval between the activation of the lightning scheme can be calculated. These flashes are then randomly distributed in time and beneath each cell. The output contains the longitude, the latitude, and the time of occurrence of each simulated discharge. Simulations of real-world scenarios are presented, which are compared to measurements with the lightning detection network, LINET. These comparisons are done on the cloud scale as well as in a mesoscale region composing southern Germany (two cases each). The flash rates of individual cumulonimbus clouds at the extreme ends of the intensity spectrum are realistically simulated. The simulated overall lightning activity over southern Germany is dominated by spatiotemporal displacements of the modeled convective clouds, although the scheme generally reproduces realistic patterns such as coherent lightning swaths.

System of Warning about Dangerous Atmospheric Phenomena in the North Caucasus for Objects of Economic Activity

2018 ◽  
Vol 931 ◽  
pp. 1019-1024
Author(s):  
Vitaliy A. Shapovalov
Keyword(s):  
Land Reclamation ◽  
Detection System ◽  
Radar Data ◽  
Automated System ◽  
Insurance Companies ◽  
North Caucasus ◽  
Weather Radars ◽  
The North ◽  
Lightning Detection ◽  
Atmospheric Phenomena

This paper presents the developed program-mathematical software for receiving, archiving, analysis and display of radar, lightning and satellite data on clouds and precipitation, interfacing of meteorological information. The program of processing of meteorological information "GIMET-2010" is established on a network of weather radars DMRL-C of the Russian Federation. An automated system combining radar and lightning detection system information applies to the command posts of the uniformed services on the fight against hail and centers of severe storm warning. Following items are provided: a receiving and transmitting to consumers the operational radar data on the actual weather; the detection, identification, and warning of hazardous weather phenomena for airports and populated areas; measurement of the intensity and amount of precipitation for agriculture, hydrological forecasts and land reclamation; obtaining precipitation map for agriculture and insurance companies.

scholarly journals Lightning environment in the vicinity of the CN tower during major storms

2021 ◽  
Author(s):  
Norhan Mansour
Keyword(s):  
Measurement System ◽  
North American ◽  
Electromagnetic Interference ◽  
Current Measurement ◽  
Average Multiplicity ◽  
Network Data ◽  
Return Stroke ◽  
The North ◽  
Lightning Detection ◽  
Intense Storm

Based on the North American Lightning Detection Network data and the return-stroke currents recorded at the CN Tower, the lightning environment within 100 km from the CN Tower is thoroughly investigated, especially while the tower was struck with major storms in 2011 and 2005. On Aug 24, 2011, video records showed that the tower was struck with 52 flashes within about 84 minutes, pointing out to the most intense storm that has ever been observed at the tower. During this most intense storm, the tower’s current measurement system recorded 32 flashes, containing 161 return strokes, resulting in an average flash multiplicity of 5, which is 80% higher than the average multiplicity of flashes occurring in the vicinity of the tower. Since the tower is repeatedly hit by lightning and its flashes produce markedly higher number of strokes, then it definitely poses an electromagnetic interference risk to nearby sensitive installations, including those in downtown Toronto.

Lightning detection system in the North Caucasus

2013 ◽  
Vol 38 (1) ◽  
pp. 1-5 ◽  
Author(s):  
A. Kh. Adzhiev ◽  
V. N. Stasenko ◽  
V. O. Tapaskhanov
Keyword(s):  
Detection System ◽  
North Caucasus ◽  
The North ◽  
Lightning Detection

scholarly journals Cloud ice fraction governs lightning rate at a global scale

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Yong Han ◽  
Hao Luo ◽  
Yonghua Wu ◽  
Yijun Zhang ◽  
Wenjie Dong
Keyword(s):  
Global Scale ◽  
Cloud Microphysics ◽  
Lightning Flash ◽  
Ice Clouds ◽  
Flash Rate ◽  
Convective Clouds ◽  
Function Relationship ◽  
Cloud Ice ◽  
Cloud Thickness ◽  
Ice Fraction

AbstractLightning flash rate is strongly influenced by cloud microphysics, such as cloud ice properties, but this relationship is poorly constrained. Here we analyze 20 years of satellite-derived lightning flash rate data and cloud water data from the ERA-Interim reanalysis above continental and ocean regions at a global scale. We find a robust modified gamma function relationship between cloud ice fraction and lightning rate. Lightning rate increases initially with increasing cloud ice fraction in stratocumulus, liquid clouds. Maximum flash rates are reached at a critical cloud ice fraction value that is associated with high top, large optical thickness, deep convective clouds. Beyond the critical value, lightning rate decreases as the ice fraction increases to values representative of cirrus, ice clouds. We find consistent critical ice fraction values over continental and oceanic regions, respectively, with a lower value over the continent due to greater cloud thickness at similar cloud top height. We suggest that our findings may help improve the accuracy of lightning forecast and hazard prediction.

scholarly journals Establishment of lightning detection sensors network in India: retrieval of essential climate variables and vulnerability mapping

2021 ◽  
Author(s):  
Alok Taori ◽  
Arun Suryavanshi ◽  
Biswadip Gharai ◽  
Sunil Pawar ◽  
M. V. R. Seshasai
Keyword(s):  
Geographical Information ◽  
Time Of Arrival ◽  
Lightning Flash ◽  
Overlay Analysis ◽  
Climate Variables ◽  
Indian States ◽  
North East ◽  
The North ◽  
Indian Space Research Organization ◽  
Lightning Detection

Abstract A network of 25 lightning detection sensors (LDS) has been established by National Remote Sensing Centre (NRSC), Indian Space Research Organization (ISRO). In the present network, sensors are located in the north-east, east coastal, central and southern locations of India. Geo-location of the lightning occurrences is estimated using time of arrival algorithm. Thus obtained lightning occurrences have been used to derive climate variables (ECVs) and to understand the vulnerable regions. We carry out overlay analysis on a Geographical Information System (GIS) platform on the monthly aggregate number of CG flash occurrences to identify the vulnerable Indian states during July 2019 to November 2020. We note that December-January reported the least number of cloud-to-ground (CG) flash occurrences while, August-September were the months with most number of CG flash occurrences. We also note that during the period under the scrutiny in this report, Chattisgarh, Jharkhand, Odisha, Maharashtra and Madhya Pradesh states recorded the most number of CG lightning flash occurrences.

scholarly journals SIMULATION OF ELECTRICAL PROCESSES IN THUNDERSTORMS IN THE NORTH CAUCASUS REGION

2017 ◽  
Author(s):  
А.В. Шаповалов ◽  
М.Ю. Пашкевич ◽  
В.И. Рязанов ◽  
В.А. Шаповалов ◽  
Н.А. Березинский ◽  
...  
Keyword(s):  
Electric Field ◽  
Three Dimensional ◽  
Volume Charge ◽  
North Caucasus ◽  
Electrical Parameters ◽  
Caucasus Region ◽  
Convective Clouds ◽  
The North ◽  
Cloud Microphysical Processes ◽  
Microphysical Processes

В работе представлена трехмерная численная модель конвективного облака с учетом электрических процессов. На основе модели получены следующие параметры: плотности объемных зарядов в облаке, потенциал и напряженность электрического поля, создаваемого этими зарядами, детально рассматривается влияние электрического поля облака на микрофизические процессы взаимодействия облачных частиц и обратное влияние – микроструктуры на электрические параметры. Приведены результаты исследований формирования термогидродинамических, микроструктурных и электрических параметров грозовых облаков в Северо-Кавказском регионе. The paper presents three-dimensional numerical model of convective clouds with the account of electrical processes. Based on the model obtained the following parameters: density of volume charge in the cloud, the potential and the electric field created by these charges, considers in detail the influence of the electric field of the cloud microphysical processes of interaction of cloud particles and the reverse influence of the microstructure on the electrical parameters. The results of thermohydrodynamic studies of the formation, microstructure and electrical parameters of storm clouds in the North Caucasus region.

scholarly journals Lightning environment in the vicinity of the CN tower during major storms

2021 ◽  
Author(s):  
Norhan Mansour
Keyword(s):  
Measurement System ◽  
North American ◽  
Electromagnetic Interference ◽  
Current Measurement ◽  
Average Multiplicity ◽  
Network Data ◽  
Return Stroke ◽  
The North ◽  
Lightning Detection ◽  
Intense Storm

Based on the North American Lightning Detection Network data and the return-stroke currents recorded at the CN Tower, the lightning environment within 100 km from the CN Tower is thoroughly investigated, especially while the tower was struck with major storms in 2011 and 2005. On Aug 24, 2011, video records showed that the tower was struck with 52 flashes within about 84 minutes, pointing out to the most intense storm that has ever been observed at the tower. During this most intense storm, the tower’s current measurement system recorded 32 flashes, containing 161 return strokes, resulting in an average flash multiplicity of 5, which is 80% higher than the average multiplicity of flashes occurring in the vicinity of the tower. Since the tower is repeatedly hit by lightning and its flashes produce markedly higher number of strokes, then it definitely poses an electromagnetic interference risk to nearby sensitive installations, including those in downtown Toronto.

Development of a Long-Range Lightning Detection Network for the Pacific: Construction, Calibration, and Performance*

2009 ◽  
Vol 26 (2) ◽  
pp. 145-166 ◽  
Author(s):  
Antti T. Pessi ◽  
Steven Businger ◽  
K. L. Cummins ◽  
N. W. S. Demetriades ◽  
M. Murphy ◽  
...  
Keyword(s):  
Pacific Ocean ◽  
Long Range ◽  
North Pacific ◽  
North Pacific Ocean ◽  
Cloud Microphysics ◽  
Lightning Flash ◽  
Central Pacific ◽  
The North ◽  
Lightning Detection ◽  
Central North Pacific

Abstract The waveguide between the earth’s surface and the ionosphere allows very low-frequency (VLF) emissions generated by lightning, called sferics, to propagate over long distances. The new Pacific Lightning Detection Network (PacNet), as a part of a larger long-range lightning detection network (LLDN), utilizes this attribute to monitor lightning activity over the central North Pacific Ocean with a network of ground-based lightning detectors that have been installed on four widely spaced Pacific islands (400–3800 km). PacNet and LLDN sensors combine both magnetic direction finding (MDF) and time-of-arrival (TOA)-based technology to locate a strike with as few as two sensors. As a result, PacNet/LLDN is one of the few observing systems, outside of geostationary satellites, that provides continuous real-time data concerning convective storms throughout a synoptic-scale area over the open ocean. The performance of the PacNet/LLDN was carefully assessed. Long-range lightning flash detection efficiency (DE) and location accuracy (LA) models were developed with reference to accurate data from the U.S. National Lightning Detection Network (NLDN). Model calibration procedures are detailed, and comparisons of model results with lightning observations from the PacNet/LLDN in correlation with NASA’s Lightning Imaging Sensor (LIS) are presented. The daytime and nighttime flash DE in the north-central Pacific is in the range of 17%–23% and 40%–61%, respectively. The median LA is in the range of 13–40 km. The results of this extensive analysis suggest that the DE and LA models are reasonably able to reproduce the observed performance of PacNet/LLDN. The implications of this work are that the DE and LA model outputs can be used in quantitative applications of the PacNet/LLDN over the North Pacific Ocean and elsewhere. For example, by virtue of the relationship between lightning and rainfall rates, these data also hold promise as input for NWP models as a proxy for latent heat release in convection. Moreover, the PacNet/LLDN datastream is useful for investigations of storm morphology and cloud microphysics over the central North Pacific Ocean. Notably, the PacNet/LLDN lightning datastream has application for planning transpacific flights and nowcasting of squall lines and tropical storms.

scholarly journals Exploring Lightning Jump Characteristics

2015 ◽  
Vol 30 (1) ◽  
pp. 23-37 ◽  
Author(s):  
T. Chronis ◽  
Lawrence D. Carey ◽  
Christopher J. Schultz ◽  
Elise V. Schultz ◽  
Kristin M. Calhoun ◽  
...  
Keyword(s):  
Lightning Flash ◽  
Autocorrelation Functions ◽  
Tracking Method ◽  
Flash Rate ◽  
Detection Systems ◽  
Storm Tracking ◽  
Lightning Detection ◽  
Random Behavior ◽  
Temporal Occurrence ◽  
Total Lightning

Abstract This study is concerned with the characteristics of storms exhibiting an abrupt temporal increase in the total lightning flash rate [i.e., lightning jump (LJ)]. An automated storm tracking method is used to identify storm “clusters” and total lightning activity from three different lightning detection systems over Oklahoma, northern Alabama, and Washington, D.C. On average and for different employed thresholds, the clusters that encompass at least one LJ (LJ1) last longer and relate to higher maximum expected size of hail, vertical integrated liquid, and lightning flash rates (area normalized) than do the clusters without an LJ (LJ0). The respective mean radar-derived and lightning values for LJ1 (LJ0) clusters are 80 min (35 min), 14 mm (8 mm), 25 kg m−2 (18 kg m−2), and 0.05 flash min−1 km−2 (0.01 flash min−1 km−2). Furthermore, the LJ1 clusters are also characterized by slower-decaying autocorrelation functions, a result that implies a less “random” behavior in the temporal flash rate evolution. In addition, the temporal occurrence of the last LJ provides an estimate of the time remaining to the storm’s dissipation. Depending on the LJ strength (i.e., varying thresholds), these values typically range between 20 and 60 min, with stronger jumps indicating more time until storm decay. This study’s results support the hypothesis that the LJ is a proxy for the storm’s kinematic and microphysical state rather than a coincidental value.

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