scholarly journals A Bayesian Approach to Assess the Performance of Lightning Detection Systems

2016 ◽  
Vol 33 (3) ◽  
pp. 563-578 ◽  
Author(s):  
Phillip M. Bitzer ◽  
Jeffrey C. Burchfield ◽  
Hugh J. Christian
Keyword(s):  
North America ◽  
Detection System ◽  
Optical Detectors ◽  
Bayesian Techniques ◽  
Detection Systems ◽  
Lightning Detection ◽  
Spatial Domains ◽  
Stroke Type ◽  
Total Lightning ◽  
Imaging Sensor

AbstractHistorically, researchers explore the effectiveness of one lightning detection system with respect to another system; that is, the probability that system A detects a discharge given that system B detected the same discharge is estimated. Since no system detects all lightning, a more rigorous comparison should include the reverse process—that is, the probability that system B detects a discharge given that system A detected it. Further, the comparison should use the fundamental physical process detected by each system. Of particular interest is the comparison of ground-based radio frequency detectors with space-based optical detectors. Understanding these relationships is critical as the availability and use of lightning data, both ground based and space based, increases. As an example, this study uses Bayesian techniques to compare the effectiveness of the Earth Networks Total Lightning Network (ENTLN), a ground-based wideband network, and the Lightning Imaging Sensor (LIS), a space-based optical detector. This comparison is completed by matching LIS groups and ENTLN pulses, each of which correspond to stroke-type discharges. The comparison covers the period from 2009 to 2013 over several spatial domains. In 2013 LIS detected 52.0% of the discharges ENTLN reported within the LIS field of view globally and 53.2% near North America. Conversely, ENTLN detected 5.9% of the pulses detected by LIS globally and 26.9% near North America in 2013. Using these results in the Bayesian-based methodology outlined, the study finds that LIS detected 80.1% of discharges near North America in 2013, while ENTLN detected 40.1%.

The Relationship between Total Cloud Lightning Behavior and Radar-Derived Thunderstorm Structure

2013 ◽  
Vol 28 (1) ◽  
pp. 237-253 ◽  
Author(s):  
Eric Metzger ◽  
Wendell A. Nuss
Keyword(s):  
Weather Type ◽  
Severe Weather ◽  
Characteristic Change ◽  
Lightning Flash ◽  
Fort Worth ◽  
Detection Systems ◽  
Lightning Detection ◽  
Rapid Changes ◽  
Total Lightning ◽  
The Relationship

Abstract Total lightning detection systems have been in development since the mid-1980s and deployed in several areas around the world. Previous studies on total lightning found intra- and intercloud lightning (IC) activity tends to fluctuate significantly during the lifetime of thunderstorms and have indicated that lightning jumps or rapid changes in lightning flash rates are closely linked to changes in the vertical integrated liquid (VIL) reading on the National Weather Service’s Weather Surveillance Radar-1988 Doppler (WSR-88D) systems. This study examines the total lightning and its relationship to WSR-88D signatures used operationally to determine thunderstorm severity to highlight the potential benefit of a combined forecast approach. Lightning and thunderstorm data from the Dallas–Fort Worth, Texas, and Tucson, Arizona, areas from 2006 to 2009, were used to relate total lightning behavior and radar interrogation techniques. The results indicate that lightning jumps can be classified into severe wind, hail, or mixed-type jumps based on the behavior of various radar-based parameters. In 25 of 34 hail-type jumps and in 18 of 20 wind-type jumps, a characteristic change in cloud-to-ground (CG) versus IC lightning flash rates occurred prior to the report of severe weather. For hail-type jumps, IC flash rates increased, while CG flash rates were steady or decreased. For wind-type jumps, CG flash rates increased, while IC flash rates either increased (12 of 18) or were steady or decreased (6 of 18). Although not every lightning jump resulted in a severe weather report, the characteristic behavior in flash rates adds information to radar-based approaches for nowcasting the severe weather type.

scholarly journals New Lightning Detection Networks in Poland – LINET and LLDN

2009 ◽  
Vol 3 (1) ◽  
pp. 29-38 ◽  
Author(s):  
Marek Loboda ◽  
Hans D. Betz ◽  
Piotr Baranski ◽  
Jan Wiszniowski ◽  
Zdzislaw Dziewit
Keyword(s):  
Detection System ◽  
High Sensitivity ◽  
Lightning Flash ◽  
Time Operation ◽  
Lightning Detection ◽  
Time Signals ◽  
Real Time Operation ◽  
Basic Characteristics ◽  
Total Lightning ◽  
The Cost

Lightning detection in Poland is performed by means of a PERUN (Safir 3000) system operated by the Institute of Meteorology and Water Management. Poland is also partly covered by a VLF/LF lightning detection system (CLDN, Central Lightning Detection Network). Both sources of lightning data have their limitations resulting from detection technique, limited number of sensors and geographical configuration, with the consequence of shortcomings in the data quality. For this reason, a new network has been installed in Poland and started continuous real-time operation in May 2006. It is LINET that covers entire Poland and is complemented by numerous sensors positioned in surrounding countries. In 2007 additional LINET sensors have been installed in Poland in order to allow exploitation of reduced baselines for efficient achievement of total lightning. In the frame of the COST P18 Action “Physics of Lightning Flash and Its Effects” another new Polish project started in 2006 related to regional lightning location. At present, the Local Lightning Detection Network (LLDN) undergoes installation in the region of Warsaw. LLDN will consist of six individual stations equipped with E-field antennae and digital recorders synchronized with GPS time signals. The aim of LLDN installation is complement other networks covering region of Warsaw (PERUN, LINET) and to provide an additional source of lightning CG data with high sensitivity in a relatively small area. In the paper are described general characteristics of LINET in Poland, as well as basic characteristics and assumed performance of LLDN, which will start operation in 2008.

scholarly journals The Intracloud Lightning Fraction in the Contiguous United States

2017 ◽  
Vol 145 (11) ◽  
pp. 4481-4499 ◽  
Author(s):  
Gina Medici ◽  
Kenneth L. Cummins ◽  
Daniel J. Cecil ◽  
William J. Koshak ◽  
Scott D. Rudlosky
Keyword(s):  
United States ◽  
Pacific Northwest ◽  
Central California ◽  
The Pacific ◽  
Lightning Detection ◽  
Maximum Period ◽  
Total Lightning ◽  
Imaging Sensor ◽  
Optical Transient

This work addresses the long-term relative occurrence of cloud-to-ground (CG) and intracloud (IC; no attachment to ground) flashes for the contiguous United States (CONUS). It expands upon an earlier analysis by Boccippio et al. who employed 4-yr datasets provided by the U.S. National Lightning Detection Network (NLDN) and the Optical Transient Detector (OTD). Today, the duration of the NLDN historical dataset has more than tripled, and OTD data can be supplemented with data from the Lightning Imaging Sensor (LIS). This work is timely, given the launch of GOES-16, which includes the world’s first geostationary lightning mapper that will observe total lightning (IC and CG) over the Americas and adjacent ocean regions. Findings support earlier results indicating factor-of-10 variations in the IC:CG ratio throughout CONUS, with climatological IC fraction varying between 0.3 and greater than 0.9. The largest values are seen in the Pacific Northwest, central California, and where Colorado borders Kansas and Nebraska. An uncertainty analysis indicates that the large values in the northwest and central California are likely not due to measurement uncertainty. The high IC:CG ratio (>4) throughout much of Texas reported by Boccippio et al. is not supported by this longer-term climatology. There is no clear evidence of differences in IC fraction between land and coastal ocean. Lightning characteristics in six selected large regions show a consistent positive relationship between IC fraction and the percent of positive CG flashes, irrespective of lightning incidence (flash density), dominant season, or diurnal maximum period.

scholarly journals Intercomparison Study of Cloud-to-Ground Lightning Flashes Observed by KARITLDS and KLDN at South Korea

2011 ◽  
Vol 50 (1) ◽  
pp. 224-232 ◽  
Author(s):  
Bong-Jae Kuk ◽  
Hong-Il Kim ◽  
Jong-Sung Ha ◽  
Hyo-Keun Lee
Keyword(s):  
Network Performance ◽  
Detection Efficiency ◽  
Detection System ◽  
Atmospheric Electricity ◽  
Correlation Method ◽  
Time Range ◽  
Lightning Detection ◽  
Space Launch ◽  
Range Correlation ◽  
Total Lightning

Abstract Concern regarding lightning activity as a precursor of severe weather is increasing. Atmospheric electricity, including lightning phenomena, is one of most serious threats to successful space launch operations. The objective of this study was to evaluate the performance of two different lightning detection networks using a time–range correlation method. Understanding lightning detection network performance enables the weather forecaster to support decisions made regarding space launch operations. The relative detection efficiency (ReDE), observation ratio, ellipse area for 50% probability of location, number of sensors reporting (NSR), time difference, and distance, as parameters that predict system performance, were calculated with the time-range correlation method using cloud-to-ground (CG) flash data from the Korea Aerospace Research Institute Total Lightning Detection System (KARITLDS) and from the Korean Meteorology Administration Lightning Detection Network (KLDN). In this study, 15 thunderstorms were selected from 2008–09 data. A total of 41 192 and 28 976 CG flashes were recorded by KARITLDS and KLDN, respectively. In all, 19 044 CG flashes were correlated as being the same flash. The observation ratios, ReDEKARITLDS, and ReDEKLDN were calculated as 1.42, 0.66, and 0.46, respectively. Eighty percent of CG flashes detected by the KARITLDS (KLDN) had elliptical areas less than 5 km2 (12 km2), where the elliptical areas were defined as having a 50% probability of containing the CG flash. Two regions showing a high observation ratio were due to high KARITLDS detection efficiency and to the blocking of electromagnetic wave propagation by Mount Hanla at 1950 m above sea level.

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.

scholarly journals Design of a Microwave Power Detection System in the 5G-Communication Frequency Band

Sensors ◽  
2021 ◽  
Vol 21 (8) ◽  
pp. 2674
Author(s):  
Qingying Ren ◽  
Wen Zuo ◽  
Jie Xu ◽  
Leisheng Jin ◽  
Wei Li ◽  
...  
Keyword(s):  
Frequency Band ◽  
Microwave Power ◽  
Communication Systems ◽  
Detection System ◽  
Measurement Sensitivity ◽  
Detection Range ◽  
Detection Systems ◽  
Detection Frequency ◽  
Communication Frequency ◽  
5G Communication

At present, the proposed microwave power detection systems cannot provide a high dynamic detection range and measurement sensitivity at the same time. Additionally, the frequency band of these detection systems cannot cover the 5G-communication frequency band. In this work, a novel microwave power detection system is proposed to measure the power of the 5G-communication frequency band. The detection system is composed of a signal receiving module, a power detection module and a data processing module. Experiments show that the detection frequency band of this system ranges from 1.4 GHz to 5.3 GHz, the dynamic measurement range is 70 dB, the minimum detection power is −68 dBm, and the sensitivity is 22.3 mV/dBm. Compared with other detection systems, the performance of this detection system in the 5G-communication frequency band is significantly improved. Therefore, this microwave power detection system has certain reference significance and application value in the microwave signal detection of 5G communication systems.

Pipeline Diagnostics With Ultrasonic Meters

2016 ◽  
Author(s):  
Nicole Gailey ◽  
Noman Rasool
Keyword(s):  
Real Time ◽  
Measurement Errors ◽  
Flow Measurement ◽  
Detection System ◽  
Leak Detection ◽  
The United States ◽  
Time Data ◽  
Critical System ◽  
Detection Systems ◽  
Transient Models

Canada and the United States have vast energy resources, supported by thousands of kilometers (miles) of pipeline infrastructure built and maintained each year. Whether the pipeline runs through remote territory or passing through local city centers, keeping commodities flowing safely is a critical part of day-to-day operation for any pipeline. Real-time leak detection systems have become a critical system that companies require in order to provide safe operations, protection of the environment and compliance with regulations. The function of a leak detection system is the ability to identify and confirm a leak event in a timely and precise manner. Flow measurement devices are a critical input into many leak detection systems and in order to ensure flow measurement accuracy, custody transfer grade liquid ultrasonic meters (as defined in API MPMS chapter 5.8) can be utilized to provide superior accuracy, performance and diagnostics. This paper presents a sample of real-time data collected from a field install base of over 245 custody transfer grade liquid ultrasonic meters currently being utilized in pipeline leak detection applications. The data helps to identify upstream instrumentation anomalies and illustrate the abilities of the utilization of diagnostics within the liquid ultrasonic meters to further improve current leak detection real time transient models (RTTM) and pipeline operational procedures. The paper discusses considerations addressed while evaluating data and understanding the importance of accuracy within the metering equipment utilized. It also elaborates on significant benefits associated with the utilization of the ultrasonic meter’s capabilities and the importance of diagnosing other pipeline issues and uncertainties outside of measurement errors.

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