scholarly journals Performance Characteristics of Distinct Lightning Detection Networks Covering Belgium

2013 ◽  
Vol 30 (5) ◽  
pp. 942-951 ◽  
Author(s):  
Dieter R. Poelman ◽  
Wolfgang Schulz ◽  
Christian Vergeiner

Abstract This study reports results from electric field measurements coupled to high-speed camera observations of cloud-to-ground lightning to test the performance of lightning location networks in terms of its detection efficiency and location accuracy. The measurements were carried out in August 2011 in Belgium, during which 57 negative cloud-to-ground flashes, with a total of 210 strokes, were recorded. One of these flashes was followed by a continuing current of over 1 s—one of the longest ever observed in natural negative cloud-to-ground lightning. Lightning data gathered from the lightning detection network operated by the Royal Meteorological Institute of Belgium [consisting of a network employing solely Surveillance et Alerte Foudre par Interférométrie Radioélectrique (SAFIR) sensors and a network combining SAFIR and LS sensors], the European Cooperation for Lightning Detection (EUCLID), Vaisala’s Global Lightning Detection network GLD360, and the Met Office’s long-range Arrival Time Difference network (ATDnet) are evaluated against this ground-truth dataset. It is found that all networks are capable of detecting over 90% of the observed flashes, but a larger spread is observed at the level of the individual strokes. The median location accuracy varies between 0.6 and 1 km, except for the SAFIR network, locating the ground contacts with 6.1-km median accuracy. The same holds for the reported peak currents, where a good correlation is found among the networks that provide peak current estimates, apart from the SAFIR network being off by a factor of 3.

2014 ◽  
Vol 142 (12) ◽  
pp. 4839-4849 ◽  
Author(s):  
Dieter R. Poelman

Abstract Temporal and spatial distributions of cloud-to-ground (CG) lightning in Belgium are analyzed. Based on data from the European Cooperation for Lightning Detection (EUCLID) network, spanning a period of 10 years between 2004 and 2013, mean CG flash densities vary between 0.3 km−2 yr−1 in the west up to 2.4 km−2 yr−1 toward the east of Belgium, with an average flash density of 0.7 km−2 yr−1. The same behavior is found in terms of thunderstorm days and hours, where in the east most of the activity is observed, with a drop-off toward the coast. The majority of lightning activity takes place in the summer months between May and August, accounting for nearly 90% of the total activity. Furthermore, the thunderstorm season reaches its highest activity in July in terms of CG detections, while the diurnal cycle peaks between 1500 and 1600 UTC. A correlation is found between the estimated peak currents and altitude, with on average higher absolute peak currents at lower elevations and vice versa. In addition, a cell tracking algorithm is applied to the data to monitor the behavior of the individual cells. It is found that the lightning cells travel at an average speed of about 25 km h−1, with a preferred northeasterly direction of movement. At last, CG flash rates are strongly related to the cell area.


2021 ◽  
Author(s):  
Savdulla Kazazi

The North American Lightning Detection Network (NALDN) has been providing lightning data since 1998. Important applications, such as detection of lightning-caused forest fires, power line fault locations and aviation safety procedures, have triggered a number of hardware and software upgrades for improving the network performance characteristics, including its detection efficiency and location accuracy. The NALDN performance characteristics are here evaluated based on the lightning currents measured at the CN Tower during three major storms (2005, 2011 and 2014). Each of these three storms followed one of the network’s substantial upgrades that took place in 2003-2004, 2010-2011 and 2013-2014. The major contribution of this extensive investigation is the determination of the network’s performance characteristics following each of the three major upgrades, which is expected to lead to additional upgrades. Since 1990, the lightning current derivatives of return strokes have been measured at the CN Tower. Its 553-m height has allowed the recording of the current derivative signals of many hundreds of return strokes. Also, imaging systems have been used to record trajectories of flashes to the tower. The evaluated performance characteristics of the network include return-stroke detection efficiency, location accuracy, and return-stroke polarity and peak current estimation. The 2013 NALDN deployment of LS7002 digital sensors with enhanced embedded software has substantially improved the sensitivity of the sensors leading to a greater return-stroke detection efficiency. Furthermore, the 2014 total lightning processor (TLP100) –designed with new algorithm - provides smaller time-of-arrival errors, leading to better location accuracy. Based on the 2014 storm evaluation, the numbers and polarities of NALDN-detected return strokes were perfectly matched with those recorded at the tower. Furthermore, based on the 2014 storm evaluation, the NALDN is found, as expected, to overestimate the current peak measured at the tower by a factor of 3.89, which is due to the field enhancement effect resulting from the high-speed of propagation of the current within the tall tower. The presented analysis shows that the latest NALDN upgrades (2013-2014), following the 2003-2004 and 2010-2011 upgrades, have substantially improved the NALDN performance characteristics, especially in terms of stroke-detection efficiency and location accuracy. Keywords: Tall-structure lightning; lightning detection; detection efficiency; location accuracy; peak current estimation.


2011 ◽  
Vol 139 (5) ◽  
pp. 1323-1337 ◽  
Author(s):  
Antti Mäkelä ◽  
Pekka Rossi ◽  
David M. Schultz

A method is developed to quantify thunderstorm intensity according to cloud-to-ground lightning flashes (hereafter ground flashes) determined by a lightning-location sensor network. The method is based on the ground flash density ND per thunderstorm day (ground flashes per square kilometer per thunderstorm day) calculated on 20 km × 20 km fixed squares. Because the square size roughly corresponds to the area covered by a typical thunderstorm, the flash density for one square defines a unit thunderstorm for the purposes of this study. This method is tested with ground flash data obtained from two nationwide lightning-location systems: the National Lightning Detection Network (NLDN) in the contiguous United States and the portion of the Nordic Lightning Information System (NORDLIS) in Finland. The distribution of daily ground flash density ND is computed for all of Finland and four 800 000 km2 regions in the United States (identified as western, central, eastern, and Florida). Although Finland and all four U.S. regions have median values of ND of 0.01–0.03 flashes per square kilometer per thunderstorm day—indicating that most thunderstorms produce relatively few ground flashes regardless of geographical region—the most intense 1% of the storms (as measured by the 99th percentiles of the ND distributions within each region) show much larger differences among regions. For example, the most intense 1% of the ND distributions is 1.3 flashes per square kilometer per thunderstorm day in the central U.S. region, but only 0.2 flashes per square kilometer per thunderstorm day in Finland. The spatial distribution of the most intense 1% of the ND distributions illustrates that the most intense thunderstorm days occur in the central United States and upper Midwest, which differs from the maxima of the average annual flash density NA and the number of thunderstorm days TD, both of which occur in Florida and along the coast of the Gulf of Mexico. This method for using ND to quantify thunderstorm intensity is applicable to any region as long as the detection efficiency of the lightning-location network is high enough or known. This method can also be employed in operational forecasting to provide a quantitative measure of the lightning intensity of thunderstorms relative to climatology.


2021 ◽  
Author(s):  
Savdulla Kazazi

The North American Lightning Detection Network (NALDN) has been providing lightning data since 1998. Important applications, such as detection of lightning-caused forest fires, power line fault locations and aviation safety procedures, have triggered a number of hardware and software upgrades for improving the network performance characteristics, including its detection efficiency and location accuracy. The NALDN performance characteristics are here evaluated based on the lightning currents measured at the CN Tower during three major storms (2005, 2011 and 2014). Each of these three storms followed one of the network’s substantial upgrades that took place in 2003-2004, 2010-2011 and 2013-2014. The major contribution of this extensive investigation is the determination of the network’s performance characteristics following each of the three major upgrades, which is expected to lead to additional upgrades. Since 1990, the lightning current derivatives of return strokes have been measured at the CN Tower. Its 553-m height has allowed the recording of the current derivative signals of many hundreds of return strokes. Also, imaging systems have been used to record trajectories of flashes to the tower. The evaluated performance characteristics of the network include return-stroke detection efficiency, location accuracy, and return-stroke polarity and peak current estimation. The 2013 NALDN deployment of LS7002 digital sensors with enhanced embedded software has substantially improved the sensitivity of the sensors leading to a greater return-stroke detection efficiency. Furthermore, the 2014 total lightning processor (TLP100) –designed with new algorithm - provides smaller time-of-arrival errors, leading to better location accuracy. Based on the 2014 storm evaluation, the numbers and polarities of NALDN-detected return strokes were perfectly matched with those recorded at the tower. Furthermore, based on the 2014 storm evaluation, the NALDN is found, as expected, to overestimate the current peak measured at the tower by a factor of 3.89, which is due to the field enhancement effect resulting from the high-speed of propagation of the current within the tall tower. The presented analysis shows that the latest NALDN upgrades (2013-2014), following the 2003-2004 and 2010-2011 upgrades, have substantially improved the NALDN performance characteristics, especially in terms of stroke-detection efficiency and location accuracy. Keywords: Tall-structure lightning; lightning detection; detection efficiency; location accuracy; peak current estimation.


2005 ◽  
Vol 20 (2) ◽  
pp. 125-133 ◽  
Author(s):  
Martin J. Murphy ◽  
Ronald L. Holle

Abstract A local maximum in cloud-to-ground (CG) lightning flash density over northwestern Mexico as measured by the U.S. National Lightning Detection Network is examined in detail. Corrections are derived for the relative detection efficiency of the network in this region that is outside the perimeter of the sensors. The need to adjust the parameters of the signal normalization model used for the network is also documented. New propagation model parameters are employed to derive relative detection efficiency corrections for northwestern Mexico and these are then used to show that the actual CG flash density over the region significantly exceeds that observed in Florida, the area with the highest flash density within the perimeter of the network.


2019 ◽  
Vol 5 (2) ◽  
pp. 1-9
Author(s):  
Deni Septiadi ◽  
Hadi Suntoko ◽  
Anton Widodo ◽  
Riza Arian Noor

The objective of this study was to identify the lightning distribution by comparing of two lightning sensors located in Jakarta and Bandung. Using Storm Tracker Lightning Detector maintained by the Indonesia Agency for Meteorology, Climatology and Geophysics (BMKG), Cloud-to-Ground lightning (CG) analyzed with a various radius i.e. 0.1˚, 0.5˚ and 1.0˚. Storm Tracker Lightning Detector consists of an antenna connected to the PCI card and able to detect Low Frequency (LF) of radio signals generated by lightning (10 KHz to 200 KHz). The data used are based on the available records of near real time 15 minutes CG lightning data. This study aims at revealing ideally possible location of the lightning sensor to optimize lightning detection. For further analysis, the distribution of the CG lightning estimated in the target area located about the middle between Jakarta and Bandung. The analysis of lightning described by calculating the detection efficiency of lightning sensor and the analysis of lightning location error.


2021 ◽  
Author(s):  
Francisco Javier Pérez-Invernón ◽  
Heidi Huntrieser ◽  
Thilo Erbertseder ◽  
Diego Loyola ◽  
Pieter Valks ◽  
...  

Abstract. Lightning is one of the major sources of nitrogen oxides (NOx) in the atmosphere, contributing to the tropospheric concentration of ozone and to the oxidising capacity of the atmosphere. Lightning produces between 2–8 Tg N per year globally and on average about 250 ± 150 mol NOx per flash. In this work, we estimate the moles of NOx produced per flash (LNOx production efficiency) in the Pyrenees (Spain, France and Andorra) and in the Ebro Valley (Spain) by using nitrogen dioxide (NO2) and cloud properties from the TROPOspheric Monitoring Instrument (TROPOMI) and lightning data from the Earth Networks Global Lightning Network (ENGLN) and from the EUropean Co-operation for LIghtning Detection (EUCLID). The Pyrenees is one of the areas in Europe with the highest lightning frequency and, due to its remoteness as well as experiencing very low NOx background, enables us to better distinguish the LNOx signal produced by recent lightning in TROPOMI NO2 measurements. We compare the LNOx production efficiency estimates for 8 convective systems in 2018 using two different sets of TROPOMI research products, provided by the Royal Netherlands Meteorological Institute (KNMI) and the Deutsches Zentrum für Luft- und Raumfahrt (DLR), respectively. According to our results, the mean LNOx production efficiency in the Pyrenees and in the Ebro Valley, using a three-hour chemical lifetime, ranges between 14 and 103 mol NOx per flash from the 8 systems. The mean LNOx production efficiency estimates obtained using both TROPOMI products and ENGLN lightning data differ by ∼23 %, while it differs by ∼35 % when using EUCLID lightning data. The main sources of uncertainty when using ENGLN lightning data are the estimation of background NOx that is not produced by lightning and the time window before the TROPOMI overpass that is used to count the total number of lightning flashes contributing to fresh-produced LNOx. The main source of uncertainty when using EUCLID lightning data is the uncertainty in the detection efficiency of EUCLID.


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