Case study on sprite and lightning activities associated with the cell life cycle in a mesoscale convective system

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On 18–20 May, 2018, we observed a total of 287 transient luminous events (TLEs) in the Taiwan campaign. After analyzing flashes from Earth Networks Total Lightning Network (ENTLN), the observation region has a maximum CG flash rate 115.1 min-1 (95.1 min-1 for –CGs and 20.0 min-1 for + CG) within a single cell of MCSs on May 20 within a radius 55 km. We investigated the TLEs activity associated with the multi-cells in the MCS, and found that sudden increases of TLEs are associated with the merging stage of new and old cells and the dissipating stage of cell. The flashes associated with TLEs with halo emissions have a tendency of large peak current. The TLEs with their parent flashes and extremely high peak currents (200, 244, 261, 267, 311, 357 kA) were shown, and most of events have common optical features of sprite halos and clusters of sprites structures. Mesoscale Convective System Transient Luminous Events Lightning Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 1. Introduction The meteorological studies on a mesoscale convective system (MCS) associated transient luminous events (TLEs) improve our understanding of TLEs production and relevant meteorological conditions. Lyons et al. studied the MCS meteorological conditions and found that the generation of TLEs is related to substantial convection and laterally stratiform rain areas (Lyons, 2006 ). Lang et al. ( 2010 ) also furtherly investigated that sprite production is associated with a convective-initiated flash region, or a stratiform-initiated flash region. They pointed out another possible scenario of sprite production in the cell mergers in thunderstorms (Lang et al., 2016 ). However, the relationship between TLE production and MCS morphology (e.g., convection or stratiform regions) is still complex. Here, we present our observational results of the Taiwan Lulin 2018 campaign. The observation provides an opportunity to study the TLE production associated with the cell lifetime (development, mature and dissipating processes) of MCS. Unlike previous reports on complex MCS meteorological environments (Lang et al., 2016 ), our case study of the cell lifetime in the MCS will help to resolve the complex MCS environment associated with TLE production. A line of MCS in summer near Taiwan could produces favorable meteorological conditions for cloud electrification, including vigorous convection and heavy rainfall especially for East Asian Summer Monsooon (Chen, 1983 ; Chen et al., 2006 ; Du et al., 2020 ; Parker and Johnson, 2000 ). The accompanying vigorous development stage of MCS can in-crease lightning activity in observation and modeling results (Chen et al., 2020 ). Due to the large-scale lifting and the moist southwesterly low-level jet (Chen et al., 2006 ), the long-sustained MCS system may also favor high lightning activity (Xu et al., 2010 ) and TLE occurrences in this study. The Taiwan Lulin 2018 campaign observed TLEs include sprites, sprite halo, and elves where sprites/sprite halo are dominated (284 events) and elves have only 3 events. Lightning with high peak current is one of the essential indicators for intense sprite-producing thunderstorms (Pizzuti et al., 2021 ). High peak cur-rent or impulse charge moment change in lightning also can cause sprite halos (Frey et al., 2007 ; Kuo et al., 2021a ; Kuo et al., 2021b ; Lu et al., 2018 ; Williams et al., 2012 ) and elves (Kolmašová et al., 2021 ; Kuo et al., 2021a ; Kuo et al., 2012 ; Parra‒Rojas et al. , 2013; Pérez-Invernón et al., 2018a ; Pérez-Invernón et al., 2018b ). The flash peak current is available from the global lightning network. In this study, we analyzed these sprite halos with their parent flashes with high-peak-current (> 200 kA) from the statistical results of the Taiwan Lulin 2018 campaign. The TLEs with their parent flashes and high peak currents > 200 kA were investigated, and all have common optical features of sprite halos and clusters of sprites structures. 2. Taiwan Lulin 2018 campaign The Lulin observatory (120◦ 52’ 25" E, 23◦ 28’ 07"N) at an altitude of 2,862 m was chosen for the Taiwan campaign in 2018 for its high transparent atmospheric conditions. The maximum distance of our observed TLE can be up to 800 km. We utilized a high-speed camera system in the Taiwan Lulin 2018 campaign (Kuo et al., 2021b ). The observation system consists of two cameras: a focal length 20 mm high-speed camera bore-sighted with a 12 mm camera and the low-light-level monochrome CCD (Watec 910HX). In this study, we used the observed TLEs by the low-light-level CCD system to investigate the meteorology environment of MCS with producing TLE flashes. Using the GPS timestamp, its time accuracy with 0.1 milliseconds (ms) can precisely deter-mine TLE’s parent lightning. The FOV of the low-light-level CCD with 30 fps is about 25.8 deg in horizontal. The camera system was auto-recorded by software in the computer. The camera system is manually operated by observers to trace the moving position of the new cell in the MCS system with flashes. The scanning angle of the camera system is about 90 deg, as shown in sector regions in Fig. 1 where an arc of the sec-tor region indicates the farthest observation distance of 800 km. Although we cannot rule out the possibility of missing TLEs, the relationship between TLEs and flash activity was definitely existed but could be underestimated. On 18–20 May 2018, a line of MCS accompanied by a cold front system occurred in our observation region during the early Meiyu season in East Asia. For the observed region, the Fujian climate report also documented the deep convection system with a hail diameter 10–20 mm and lasting 2 minutes. We analyzed the cell area and cloud top temperature from Taiwan CWB (Central Weather Bureau) processing data using Japan Meteorological Agency Himawari satellite to trace the development conditions within a single cell of the MCS. We derived their cloud top height from using a back-ground temperature profile from the closest balloon-sounding data where the balloon-launching site is only distanced within 200 km in our studies. Besides, we analyzed radar reflectivity data from Taiwan weather radar network (S-band Doppler single-polarization radars). The maximum radar reflectivity indicates the heavy precipitation region in the thunderstorm. Drawing out the maximum reflectivity associated with flash/TLEs helps us to recognize the spatial relationship between cell development and flash/TLEs activity, also seeing Sections 3.1 and 3.2 . We analyzed the flash activity in the MCS associated with TLE using Earth Networks Total Lightning Network (ENTLN) dataset. The ENTLN uses the time-of-arrival detection methodology with GPS technology and sophisticated algorithms to accurately locate and classify lightning types. A sensor includes wideband electrical field recorders (frequency ranging from 1HZ to 12MHZ), a GPS receiver, a nano-second GPS-based timing circuit, a digital signal processor (DSP), onboard storage and internet communication equipment. As a result of the advanced predictive abilities and global deployment of ENTLN, it has the potential to significantly improve severe weather warning times over radar and other technologies (Bui et al., 2015 ; Zhu et al., 2017 ; Zhu et al., 2022 ). Lightning also helps us to study the electrical activity of MCS. However, ENTLN data were available for close regions of our TLE observation on May 20. Besides, the radar reflectivity data of a thunderstorm system from the Weather dataset of Taiwan CWB is limited only for the close observation region. For the far region of our observation on 18–19 May, we used WWLLN (World Wide Lightning Lo-cation Network) lightning data. The WWLLN is a real-time, worldwide, ground-based network operated by the University of Washington that can detect extreme lightning events occurring anywhere in the world. The WWLLN network's purpose was to achieve global detection with a location accuracy of fewer than 10 km (Rodger et al., 2006 ). The WWLLN receivers operate in the VLF band and detect the lightning wave packet that propagates in the region between the Earth and the lower ionosphere. These wave packets propagate in particular waveguide modes (TE, TM or TEM), which effectively obscure the polarity of the parent lightning strokes (Abarca et al., 2010 ; Hutchins et al., 2012a ; Hutchins et al., 2012b ; Jacobson et al., 2021 ; Rodger et al., 2006 ). Hence, the WWLLN dataset provide the peak current and the corresponding location of TLEs’ parent lightning but without their polarity. 3. Observation Results 3.1. Thunderstorm and lightning activity associated with TLEs on May 20 Three distinct periods for the lightning evolution inside the observed MCS on May 20, 2018 are categorized as: (1) the development stage (before 20:00 LT), (2) the mature stage (20:10–21:40 LT), and (3) the dissipating stage (21:40 LT -). Figures 2 a- 2 d shows four characteristic snapshots at 20:00, 20:30, 21:00 and 23:00 LT for the development stage, first observed TLE, the mature stage, and the dissipating stage, respectively. We can observe the merging of a new cell (dashed-line circle) and an old cell of the line of MCSs in Figs. 2 a- 2 d. Within the merging of two cells, the new cell expanded their cloud region while the old cells shrank the cloud area. The interaction process between two cells were also accompanied by the first observed TLE in Fig. 2 b. In the mature stage of the MCS, observed TLEs were scattered in the stratiform region of the new cell. The results were consistent with previous TLE studies (Lang et al., 2016 ; Lang et al., 2010 ). The criteria of the three stages are defined based on the maximum cloud top height. Figures 2 e- 2 j show the temporal curves for cloud properties associated with ENTLN/WWLLN flash and TLE activities. The updraft in the convective region in-creased the cloud height to a maximum value of 16 km at ~ 20:10 LT, shown in Fig. 2 e. The characteristic time at 20:10 LT corresponds to the transition from the development sage to the mature stage. That implies that the concurrence of updraft and downdraft in the convective region stopped gaining cloud top height for the mature stage. After 20:10 LT, the downdraft activity inside the cell may cause a slight down-ward trend of the cloud top height. Two local maximum values of ~ 18 km imply small-scale updrafts in the mature stage. After 21:40 LT, the cloud height gradually decreased less than 16 km. An updraft ceases, and the downdraft is dominated for the dissipating stage. The lower cloud height explains that the cell developed into its dissipating phase. In Figs. 2 f and 2 g, the new cell of the thunderstorm had a maximum area of cloud (9.3x10 3 km 2 ) in the dissipating stage at 22:30 LT while their maximum radar area (> 40 dB) is 2.3×10 3 km 2 at 22:20 LT. The dissipating state of the cell had their maximum values of radar reflectivity area (> 40 dB) and cloud area (h > 12 km) with ~ 90 minutes delay after a peak time (20:50 LT) of ENTLN CG flash rate 115.1 min − 1 where 95.1 min − 1 for –CGs and 20.0 min − 1 for + CG), respectively in yellow and orange lines of Figs. 2 h and WWLLN CG flash rate 26.6 min − 1 in green line of Fig. 2 i. In Fig. 2 j, two distinct periods of TLE activity occurs from 20:30 to 21:30 LT and after 22:50 LT, corresponding to the mature stage and the dissipating stage of lightning activity. We studied the radar reflectivity intensity for TLE’s parent lightning locations with considering possible displacement 10 km within TLEs (van der Velde et al., 2006 ). For the period of the mature stage, the maximum reflectivity was 44 ± 8 dB while a lower value of 31 ± 6 dB for the dissipating state. In previous studies, the average reflectivity generally ranges between 30 to 35 dB at a distance of 10 km near TLEs’ parent lightning (van der Velde et al., 2006 ) while TLE associated + CG located in the stratiform region of the MCS with a radar reflectivity between 25–35 dB (Pan et al., 2021 ). Besides, recent report also found the TLEs’ parent lightning in the convective region and stratiform region of the MCS (Suzuki et al., 2022 ) while previous studies only observed TLE above the stratiform region of MCS (Suzuki et al., 2022 and references therein; Yang et al., 2018 ). 3.2. Observed TLEs during the cell merging and the dissipation of a thunderstorm system Cell merging is one of important processes to intensify the convective system (Westcott, 1994 ). Lu et al. (Lu et al., 2022 ) investigate the cell merging and corresponding lightning activity using observation and simulation. Their results support that cell merging can enhance the lightning activity. The strong updraft via the horizontal transport of ice-phase particles may increases the collision rate and enhance the electrification. The cloud bridge between two merging cell is one of lightning surged region (Lu et al., 2022 ). In Figures A (a) and A (b) of supplement materials, we can identify the newly detected flashes (red dashed circles) inside the cloud bridge between old and new cells on 20:10 LT, May 20. From 20:10 LT to 21:00 LT, the cloud bridge in-creased its size, and finally merged into the new cell after 21:00 LT. Figure 3 shows the maximum radar reflectivity and their vertical profiles at three characteristic times (development, mature and dissipating) where the maximum radar reflectivity is overlaid with ENTLN flashes in Figs. 3 a, 3 b, and 3 c. Their cutting profiles of radar reflectivity along the cell moving direction in Figs. 3 d, 3 e, and 3 f and perpendicular to the moving line in Figs. 3 g, 3 h, and 3 i. The ENTLN flashes are highly correlated in spatial distribution with the high reflectivity (> 40dB) in the development and the mature stage of the thunderstorm in the projected area of Figs. 3 a, and 3 b. But, at the dissipating stage in Fig. 3 c, a lower number of flashes was widely distributed above the radar reflectivity > 30 dB. In Fig. 3 b, we show an interesting case of merging two lightning cluster in a squall line system. The merging of two charge systems of the new cell and the old cell in a squall line may explain the increases of our observed TLE events. Found the observed number of TLEs in Fig. 2 j, the first sudden increase happened from 20:10 LT to 21:00 LT during the cell merging of a thunderstorm system. The TLEs’ parent lightning scattered in the new cell and the merging area, shown in red dots of Fig. 3 b. From 20:10 to 21:40 LT, the merged convective system has more flash numbers, while the old cell and new cell of the MCS produce more TLEs and flash rates than the later time in dissipating period after 21:30 LT. In a line of MCS, the balance between convectively-induced low-level cold pool strength and depth under heavy rain and the ambient low-level wind shear may trigger new cells and could provide the atmospheric environment with strong convection. The intensity of the cell may be related with their high flash rate. Besides, the TLEs’ parent flashes were located in the cloud bridge and the new cell during the cell merging, as shown by red dots in Fig. 3 b. Our observation supports the flash and TLEs’ parent flashes in the MCS convective region, especially during cell merging process. The measured flash rates had their peak values in yellow and orange lines in Fig. 2 h for ENTLN + CG/-CG, respectively, and green line in Fig. 2 i for WWLLN CG. The ENTLN/WWLLN flash rate in Fig. 2 h /2i and TLE rate in Fig. 2 j reach their maximum values around 20:50 LT. That may imply that the cell merging between 20:10 to 21:40 LT not only increases the probability of flashes but ENTLN + CG per-centage also boost the TLE numbers in this case study. During the thunderstorm dissipating stage, the CG flash rates decreased from 104.5 min-1 at 21:00 LT to 9.0 min-1 at 23:00 LT, while the TLE rate was constantly maintained at 1–2 events per ten minutes. The + CG in the stratiform of MCS (Lang et al., 2004 ) could provide the electrical environment of producing TLEs (Lang et al., 2016 ; Lang et al., 2010 ). Besides, the ENTLN measured +/- IC flash of the dissipating thunderstorm also decreases their height. After 23:20 LT, TLE activity was enhanced again. We will furtherly discuss it in Section 4.1 . 4. Discussions 4.1. The sprite activity associated with ENTLN + CG percentage and WWLLN high peak current flash ratios To clarify the correlations between TLEs and lightning activity in mature and dissipating stages, we analyzed the ENTLN + CG percentage and the WWLLN high peak current percentage in Fig. 4 . The + CG percentage could be used to investigate the probability of producing TLE flash since greater than 99.9% sprites are produced by + CG flash (Chen et al., 2019 ). High peak current lightning may favor halo and sprite halo occurrences (Williams et al., 2012 ). In Fig. 4 a, we consider the ENTLN CG flash rate ( R ENTLN ) and WWLLN CG flash rate ( R WWLLN ) per 10 minutes’ bin. A scatter plot in Fig. 4 a shows the ENTLN and WWLLN CG flash rate per 10 minutes in Figs. 1 d and 1 e. Their linear relationship can be formulated by R WWLLN = 0.2105 × R ENTLN + 0.3414 with a correlation coefficient 0.9663. Hence, the percentage calculation for + CG and high peak current won’t be varied by detected flash rates. Hence, the detected flash rates of ENTLN and WWLLN should have a linear relationship. We examined two indicators (ENTLN + CG percentage and WWLLN large peak current percentage) per 10 minutes’ bin. In Figs. 4 b and 4 c, we testify the ENTLN + CG percentage and WWLLN large peak current percentage (the percentages of peak currents I > 100kA and I > 60kA) for TLE numbers per 10 minutes. The flash peak current 60 kA is required minimum current for elves emissions (Barrington-Leigh and Inan, 1999 ) and 100 kA is proposed by large peak current in work of (Pizzuti et al., 2021 ). In addition, positive or negative flashes with peak current > 50 kA and a total charge moment > 500 C-km may explain the occurrence of diffuse halo emissions (Williams et al., 2012 ). Figure 2 j shows two active periods of TLEs during 20:25 − 21:25 LT and after 21:55 LT. The first TLE activity during 20:25 − 21:25 LT corresponded to a surge of the ENTLN + CG percentage in Fig. 4 b, where the ENTLN + CG percentage increased from 6.8% at 19:50 LT to 18.7% at 20:40 LT, and decreased to 15.8% at 21:30 LT. After 21:40 LT, the CG rate decreased but the observed TLEs had 1–2 events per 10 minutes after 21:55 LT in Fig. 2 j. After 23:15 LT, observed TLEs increased to 3 events per 10 minutes. In Fig. 4 b, the ENTLN + CG percentage jumped to its peak value of 31.3% at 23:20 LT while the WWLLN large peak current (I > 100kA) has its local peaks at 23:20 LT, especially for second TLEs activity. The percentage of higher peak current, e.g., I > 200kA, is expected as similar to the plot of I > 100 kA, but is not sensitive as the percentage of I > 100kA. Most –CG cannot have both of large peak current and long continuing current to favor sprite production (Saba et al., 2006 ). Most + CG with continuing current and high charge transferred may associated with the sprite and sprite halos (Williams et al., 2012 ). In our case study, the mature thunderstorm stage with a high + CG rate may favor in the sprite production. In addition, a high peak current flash may cause the sprite halos in our case study of thunderstorm dissipating stage. Pizzuti et al. ( 2021 ) found that intense lightning discharge with large peak current > 100 kA, although not directly related to the total amount of charge transferred. Therefore, a high + CG rate with high peak currents may contribute the probability of sprite halo and sprites in our case study. We will discuss it on WWLLN measured peak currents between TLEs’ parent flashes and flashes without observed TLEs in next session. 4.2. Sprite halos produced by high peak current flashes Lyons et al. ( 1998 ) reported the + CG associated with sprites typically have large peak current. Their study indicates that the + CG peak current associated with sprites averaged 81 kA versus 30 kA for other + CG in the same MCS. Large peak current -CG may cause the pure halo (Frey et al., 2007 ; Williams et al., 2012 ), elves (Barrington-Leigh and Inan, 1999 ; Kuo et al., 2012 ; Pérez-Invernón et al., 2018b ; Wu et al., 2017 ) and sprites (Chen et al., 2019 ). Hence, we are interested to compare the probability of flash peak current associated with sprite in the MCS on May18-21, 2018, especially for a long-sustained weather system of the East Asian Summer Monsoon. First, we show the +/-CG peak current probability distribution in Fig. 5 . We assume that the + CG percentage of total + CG/-CG are almost equal since + CG is roughly 10% of total flash. Second, we compare the TLE associated peak current probability distribution and the total flash in Fig. 6 . Table 1 The peak current and time of flash associated with selected sprites in 2018 Taiwan campaign. Figure 9 Date Event Time 1 Flash time 2 I(kA) 3 a May 18 22:54:26.7413 22:54:26.7094 200 b May 18 23:57:59.8950 23:57:59.8690 244 c May 19 21:16:03.0469 21:16:03.0229 357 d May 20 20:58:12.4350 20:58:12.4054 311 e May 20 22:04:31.5199 22:04:31.4848 261 f May 20 23:47:50.4597 23:47:50.4091 267 1 GPS timetag time (LT) from TLE observation; 2 WWLLN flash time (LT); 3 WWLLN measured peak current of parent lightning in units of kilo-ampere (kA) Figure 5 a shows the histogram plots for the WWLLN measured peak current in units of kA at nights from LT 20:00 to 04:00 next day on May18-21, 2018. In these observation regions, we analyzed a total 19,380 flashes from the WWLLN dataset. The median of the peak currents of flashes in our observation region is 45.2 kA. Hence, for the probability function of their peak currents in this case study, we consider the lognormal distribution as a probability density function P log (I) for the best fitting function for peak current I as one of best fitting distribution function (Cummer et al., 2013 ), $${\text{P}}_{log}\left(\text{I}|{\mu }, {\sigma }\right)=\frac{1}{\text{I}{\sigma }\sqrt{2\pi }}exp\left\{\frac{-{\left(\text{l}\text{o}\text{g}\left(I\right)-{\mu }\right)}^{2}}{2{\sigma }^{2}}\right\}$$ 1 where the mean µ and variance σ are fitting values for lognormal distribution. Shown with all flash at nights in Fig. 5 b, the cumulative probability at 50%, 75%, and 95% corresponds to peak currents 47.6 kA, 66.0 kA, and 105.4 kA, respectively. Figure 5 b shows the cumulative probability for flash peak current where cumulative probability at 50% corresponds to peak current 47.6 kA. In comparison with 2010 WWLLN’s results, the cumulative probability of 50% indicate the flash peak current 42 kA (Hutchins et al., 2012a ). Our results show the cumulative probability ~ 90% for flash peak current (< 100 kA), also shown in Fig. 5 b. According to the parameterization studies of TLEs based on WWLLN dataset in 2016, the WWLLN flash peak currents (< 100 kA) account for 86% (Evtushenko et al., 2022 ). But these CGs with peak current 100–200 kA is quite important for triggering sprites, about 11% of flashes in 2016 WWLLN dataset (Evtushenko et al., 2022 ) where CGs with > 200 kA is fewer (3%). It is noted that the stroke power and related peak current measured by WWLLN has substantial seasonal and interannual variability and also depends on the number of active WWLLN stations. For example, for the median stroke power, there is a near-continuous decrease from 2013 to the end of 2020 (Kaplan and Lau, 2021 ; 2022 ). Figure 6 shows WWLLN peak currents associated with observed TLEs within a time window (before 300 ms and after + 33 ms). For that time window, flash peak cur-rents have a cumulative probability of 50%, 75%, and 95% for 81.5 kA, 147.8 kA, and 252 kA, respectively. The TLE-associated flashes with peak currents > 100 kA and 200 kA have the cumulative probability of 66.2% and 91.7%, respectively. Our results show that ~ 9.3% of TLEs’ parent flashes have TLE’s parent lightning peak currents greater than 200 kA. For studies on parent lightning peak currents for sprites, we categorized our observed sprites with WWLLN measured peak currents as the group for column sprites, carrot sprites and tree sprites (Bór, 2013 ). We avoid to misclassify events between wishbone, angel and tree sprites since the spatial resolution of some recorded images are too low. In our study, we consider the major morphological classes: column sprites, carrot sprites and tree sprites. The sprite event was distinguished based on the time difference of > 2 frames and the spatial displacement of > 50 km (Bór, 2013 ). We analyzed 144 events out of 284 recorded events after we excluded the unclassified events and no-identified peak current in a time window of before 300 ms and after + 33 ms. The number for column sprites, carrot sprites and tree sprites are 11, 94, and 33 events, respectively. The peak currents of their parent lightning are shown in histogram plots in Fig. 7 . Figure 8 also show the peak current histogram for sprites without halo or with halos where halo was identified as the intensity which is greater than 3σ of background signals where σ is the standard deviation or their disk-shape halo emissions in the recorded images. The results show the tendency that higher peak current for sprites with halos have the larger peak current. Although energetic positive CGs with large charge moment change (CMC) are known for their capability for producing sprites (Cummer and Inan, 1997 ; Kohlmann et al., 2022 ; Lu et al., 2009 ; Mlynarczyk et al., 2015 ), this study also suggest that high peak current of TLEs’ parent lightning would be a good indicator for TLEs, especially for sprite halo. Their impulse peak current radiates the inducing electric field and causes the sprite halo emission (Kuo et al., 2021b ; Pérez-Invernón et al., 2018a ; Pérez-Invernón et al., 2018b ). Cummer et al. ( 2013 ) estimated a minimum value of iCMC (> 300 C-km) for + CG and iCMC (> 500 C-km) for –CG where iCMC indicates the total charge moment change over the first 2 ms of the lightning stroke (Cummer et al., 2013 ). Positive or negative flashes with peak current > 50 kA and a total charge moment > 500 C-km may explain the occurrence of diffuse halo emissions (Williams et al., 2012 ). Figure 9 shows six TLE events with disk-shape halo emissions and their parent lightning with high-peak-current (> 200 kA) listed in Table 1 . The optical features of sprites with their high-peak-current parent lightning are: (1) visible halos, (2) column sprites or carrot sprites, (3) clusters sprites or so-called jellyfish sprites. In Fig. 9 c, a sprite event with a peak current 357 kA has a large cluster of carrot sprites with a visible halo emission, also called by jellyfish sprite. 5. Summary The MCS evolution was traced and studied using meteorological/lightning/sprites analyses. We show three time periods for lightning activity inside the sprite-producing thunderstorm, their synoptic condition, and temporal curves for cloud properties (cloud area, maximum cloud height, radar reflectivity) and ENTLN/WWLLN flash rates and sprite rates. We analyzed the relationship between the meteorological condition of MCS, flash and TLE activities at night on May 20, 2018. Three time periods (20:00/21:00/23:00 LT) indicate the significant stages for MCS evolution using lightning activity: (1) development stage (before 20:00 LT), (2) mature stage (20:10–21:40 LT), and (3) dissipating stage (after 21:40 LT), respectively. First observed sprite occurred at 20:30 during the merging period of the MCS evolution. Another increase of TLE was also found in the decaying stage of the MCS. The main findings of our observation are summarized as follows: (1) The Mei-Yu season in May-June is one of the most severe weather phenomena with heavy rainfall in the early-summer rainy season over east-south Asia. A line of mesoscale convective systems (MCSs) provides strong updraft and severe lightning, and produces favorable weather conditions for high flash rates and sprite occurrences. (2) The observation supports the previous studies of transient luminous events associated with the mature stage and the dissipating stage of a thunderstorm system, especially for first TLE during cell-merging on 20:10–21:00 LT (Lang et al., 2016 ; Lang et al., 2010 ). (3) The parent flash of TLEs had larger peak current for TLEs with distinguished halo emissions. (4) The optical features of sprites with their parent flash of peak current > 200 kA are: a visible halo, column sprites or carrot sprites, and clusters of sprites. (5) The peak current of TLEs’ parent lightning could be a good indicator for TLE, especially for sprite halo. Declarations Author Contributions : Methodology and formal analysis H. Y. H and C.-L. K.; writing—original draft preparation, H. Y. H, C.-L. K and R.-R. H.; radar data provided, C.-Y. H.; supervision, R.-R. H. and L.-C. L. All authors have read and agreed to the published version of the manuscript. Funding : This research was funded by MOST 111-2111-M-008-008, MOST 110-2111-M-008-007, MOST 109-2111-M-008-006 and MOST 108-2111-M-008-005 funded by Ministry of Science and Technology of Taiwan. Acknowledgments : The authors would like to thank the service from Ministry of Science and Technology & Chinese Culture University, Data Bank for Atmospheric and Hydrologic Research. They would like to thank Prof. Bob Holzworth (WWLLN) for providing the lightning data for this study. Conflicts of Interest : The authors declare no conflict of interest. References Abarca, S. F., K. L. Corbosiero, and T. J. Galarneau Jr. (2010), An evaluation of the Worldwide Lightning Location Network (WWLLN) using the National Lightning Detection Network (NLDN) as ground truth, Journal of Geophysical Research: Atmospheres, 115 (D18), doi: https://doi.org/10.1029/2009JD013411 . Barrington-Leigh, C. P., and U. S. Inan (1999), Elves triggered by positive and negative lightning discharges, Geophysical Research Letters, 26 , 683–686. Bór, J. (2013), Optically perceptible characteristics of sprites observed in Central Europe in 2007–2009, Journal of Atmospheric and Solar-Terrestrial Physics, 92 , 151–177, doi: https://doi.org/10.1016/j.jastp.2012.10.008 . Bui, V., L.-C. Chang, and S. Heckman (2015), A Performance Study of Earth Networks Total Lighting Network (ENTLN) and Worldwide Lightning Location Network (WWLLN) , 386–391 pp., doi: 10.1109/CSCI.2015.120 . Chen, A. B.-C., H. Chen, C.-W. Chuang, S. A. Cummer, G. Lu, H.-K. Fang, H.-T. Su, and R.-R. Hsu (2019), On negative Sprites and the Polarity Paradox, Geophysical Research Letters, 46 (16), 9370–9378, doi: https://doi.org/10.1029/2019GL083804 . Chen, T. J. (1983), Observational Aspects of the Mei-Yu Phenomenon in Subtropical China, Journal of the Meteorological Society of Japan. Ser. II, 61 (2), 306–312, doi: 10.2151/jmsj1965.61.2_306 . Chen, T. J., C. C. Wang, and L. F. Lin (2006), A Diagnostic Study of a Retreating Mei-Yu Front and the Accompanying Low-Level Jet Formation and Intensification, Monthly Weather Review, 134 (3), 874–896, doi: 10.1175/mwr3099.1 . Chen, Z., X. Qie, Y. Yair, D. Liu, X. Xiao, D. Wang, and S. Yuan (2020), Electrical evolution of a rapidly developing MCS during its vigorous vertical growth phase, Atmospheric Research, 246 , 105201, doi: https://doi.org/10.1016/j.atmosres.2020.105201 . Cummer, S. A., and U. S. Inan (1997), Measurement of charge transfer in sprite-producing lightning using ELF radio atmospherics, Geophysical Research Letters, 24 (14), 1731–1734, doi: https://doi.org/10.1029/97GL51791 . Cummer, S. A., W. A. Lyons, and M. A. Stanley (2013), Three years of lightning impulse charge moment change measurements in the United States, Journal of Geophysical Research: Atmospheres, 118 (11), 5176–5189, doi: https://doi.org/10.1002/jgrd.50442 . Du, Y., Z. Q. Xie, and Q. Miao (2020), Spatial Scales of Heavy Meiyu Precipitation Events in Eastern China and Associated Atmospheric Processes, Geophysical Research Letters , 47 (11), e2020GL087086, doi: https://doi.org/10.1029/2020GL087086 . Evtushenko, A., N. Ilin, and E. Svechnikova (2022), Parameterization and global distribution of sprites based on the WWLLN data, Atmospheric Research, 276 , 106272, doi: https://doi.org/10.1016/j.atmosres.2022.106272 . Frey, H. U., et al. (2007), Halos generated by negative cloud-to-ground lightning, Geophysical Research Letters, 34 (18), L18801, doi:doi: 10.1029/2007gl030908 . Hutchins, M. L., R. H. Holzworth, J. B. Brundell, and C. J. Rodger (2012a), Relative detection efficiency of the World Wide Lightning Location Network, Radio Science, 47 (6), doi: https://doi.org/10.1029/2012RS005049 . Hutchins, M. L., R. H. Holzworth, C. J. Rodger, and J. B. Brundell (2012b), Far-Field Power of Lightning Strokes as Measured by the World Wide Lightning Location Network, Journal of Atmospheric and Oceanic Technology, 29 (8), 1102–1110, doi: 10.1175/jtech-d-11-00174.1 . Jacobson, A. R., R. H. Holzworth, and J. B. Brundell (2021), Using the World Wide Lightning Location Network (WWLLN) to Study Very Low Frequency Transmission in the Earth-Ionosphere Waveguide: 1. Comparison With a Full-Wave Model, Radio Science , 56 (7), e2021RS007293, doi: https://doi.org/10.1029/2021RS007293 . Kaplan, J. O., and K. H. K. Lau (2021), The WGLC global gridded lightning climatology and time series, Earth Syst. Sci. Data, 13 (7), 3219–3237, doi: 10.5194/essd-13-3219-2021 . Kaplan, J. O., and K. H. K. Lau (2022), World Wide Lightning Location Network (WWLLN) Global Lightning Climatology (WGLC) and time series, 2022 update, Earth Syst. Sci. Data, 14 (12), 5665–5670, doi: 10.5194/essd-14-5665-2022 . Kohlmann, H., W. Schulz, and F. Rachidi (2022), Estimation of Charge Transfer During Long Continuing Currents in Natural Downward Flashes Using Single-Station E-Field Measurements, Journal of Geophysical Research: Atmospheres, 127 (6), e2021JD036197, doi: https://doi.org/10.1029/2021JD036197 . Kolmašová, I., et al. (2021), First Observations of Elves and Their Causative Very Strong Lightning Discharges in an Unusual Small-Scale Continental Spring-Time Thunderstorm, Journal of Geophysical Research: Atmospheres, 126 (1), e2020JD032825, doi: https://doi.org/10.1029/2020JD032825 . Kuo, C.-L., T.-Y. Huang, C.-M. Hsu, M. Sato, L.-C. Lee, and N.-H. Lin (2021a), Resolving Elve, Halo and Sprite Halo Images at 10,000 Fps in the Taiwan 2020 Campaign, Atmosphere, 12 (8), 1000. Kuo, C.-L., E. Williams, T. Adachi, K. Ihaddadene, S. Celestin, Y. Takahashi, R.-R. Hsu, H. U. Frey, S. B. Mende, and L.-C. Lee (2021b), Experimental Validation of N2 Emission Ratios in Altitude Profiles of Observed Sprites, Frontiers in Earth Science, 9 , doi: 10.3389/feart.2021.687989 . Kuo, C. L., et al. (2012), Full-kinetic elve model simulations and their comparisons with the ISUAL observed events, Journal of Geophysical Research: Space Physics, 117 (A7), doi: https://doi.org/10.1029/2012JA017599 . Lang, T. J., W. A. Lyons, S. A. Cummer, B. R. Fuchs, B. Dolan, S. A. Rutledge, P. Krehbiel, W. Rison, M. Stanley, and T. Ashcraft (2016), Observations of two sprite-producing storms in Colorado, Journal of Geophysical Research: Atmospheres, 121 (16), 9675–9695, doi: https://doi.org/10.1002/2016JD025299 . Lang, T. J., W. A. Lyons, S. A. Rutledge, J. D. Meyer, D. R. MacGorman, and S. A. Cummer (2010), Transient luminous events above two mesoscale convective systems: Storm structure and evolution, Journal of Geophysical Research: Space Physics, 115 (A5), doi: https://doi.org/10.1029/2009JA014500 . Lang, T. J., S. A. Rutledge, and K. C. Wiens (2004), Origins of positive cloud-to-ground lightning flashes in the stratiform region of a mesoscale convective system, Geophysical Research Letters, 31 (10), doi: https://doi.org/10.1029/2004GL019823 . Lu, G., S. A. Cummer, J. Li, F. Han, R. J. Blakeslee, and H. J. Christian (2009), Charge transfer and in-cloud structure of large-charge-moment positive lightning strokes in a mesoscale convective system, Geophysical Research Letters, 36 (15), doi: https://doi.org/10.1029/2009GL038880 . Lu, G., B. Yu, S. A. Cummer, K.-M. Peng, A. B. Chen, F. Lyu, X. Xue, F. Liu, R.-R. Hsu, and H.-T. Su (2018), On the Causative Strokes of Halos Observed by ISUAL in the Vicinity of North America, Geophysical Research Letters, 45 (19), 10,781 – 710,789, doi: https://doi.org/10.1029/2018GL079594 . Lu, J., et al. (2022), Effects of Convective Mergers on the Evolution of Microphysical and Electrical Activity in a Severe Squall Line Simulated by WRF Coupled With Explicit Electrification Scheme, Journal of Geophysical Research: Atmospheres , 127 (16), e2021JD036398, doi: https://doi.org/10.1029/2021JD036398 . Lyons, W. A. (2006), The meteorology of transient luminous events-an introduction and overview, Springer Netherlands, Dordrecht. Lyons, W. A., M. Uliasz, and T. E. Nelson (1998), Large Peak Current Cloud-to-Ground Lightning Flashes during the Summer Months in the Contiguous United States, Monthly Weather Review, 126 (8), 2217–2233, doi: https://doi.org/10.1175/1520-0493(1998)1262.0.CO;2 . Mlynarczyk, J., J. Bór, A. Kulak, M. Popek, and J. Kubisz (2015), An unusual sequence of sprites followed by a secondary TLE: An analysis of ELF radio measurements and optical observations, Journal of Geophysical Research: Space Physics, 120 (3), 2241–2254, doi: https://doi.org/10.1002/2014JA020780 . Pan, C., J. Yang, K. Liu, and Y. Wang (2021), Comprehensive Analysis of a Coast Thunderstorm That Produced a Sprite over the Bohai Sea, Atmosphere, 12 (6), 718. Parker, M. D., and R. H. Johnson (2000), Organizational Modes of Midlatitude Mesoscale Convective Systems, Monthly Weather Review, 128 (10), 3413–3436, doi: 10.1175/1520-0493(2001)1292.0.CO;2 . Parra–Rojas, F. C., A. Luque, and F. J. Gordillo–Vázquez (2013), Chemical and electrical impact of lightning on the Earth mesosphere: The case of sprite halos, Journal of Geophysical Research: Space Physics, 118 (8), 5190–5214, doi: https://doi.org/10.1002/jgra.50449 . Pérez-Invernón, F. J., A. Luque, and F. J. Gordillo-Vázquez (2018a), Modeling the Chemical Impact and the Optical Emissions Produced by Lightning-Induced Electromagnetic Fields in the Upper Atmosphere: The case of Halos and Elves Triggered by Different Lightning Discharges, Journal of Geophysical Research: Atmospheres, 123 (14), 7615–7641, doi: https://doi.org/10.1029/2017JD028235 . Pérez-Invernón, F. J., A. Luque, F. J. Gordillo-Vázquez, M. Sato, T. Ushio, T. Adachi, and A. B. Chen (2018b), Spectroscopic Diagnostic of Halos and Elves Detected From Space-Based Photometers, Journal of Geophysical Research: Atmospheres, 123 (22), 12,917 – 912,941, doi: https://doi.org/10.1029/2018JD029053 . Pizzuti, A., J. M. Wilkinson, S. Soula, J. Mlynarczyk, I. Kolmašová, O. Santolík, R. Scovell, A. Bennett, and M. Füllekrug (2021), Signatures of large peak current lightning strokes during an unusually intense sprite-producing thunderstorm in southern England, Atmospheric Research, 249 , 105357, doi: https://doi.org/10.1016/j.atmosres.2020.105357 . Rodger, C. J., S. Werner, J. B. Brundell, E. H. Lay, N. R. Thomson, R. H. Holzworth, and R. L. Dowden (2006), Detection efficiency of the VLF World-Wide Lightning Location Network (WWLLN): initial case study, Ann. Geophys., 24 (12), 3197–3214, doi: 10.5194/angeo-24-3197-2006 . Saba, M. M. F., O. Pinto Jr., and M. G. Ballarotti (2006), Relation between lightning return stroke peak current and following continuing current, Geophysical Research Letters, 33 (23), doi: https://doi.org/10.1029/2006GL027455 . Suzuki, T., M. Kamogawa, H. Fujiwara, and S. Hayashi (2022), MCS Stratiform and Convective Regions Associated with Sprites Observed from Mt. Fuji, Atmosphere , 13 (9), 1460. van der Velde, O. A., Á. Mika, S. Soula, C. Haldoupis, T. Neubert, and U. S. Inan (2006), Observations of the relationship between sprite morphology and in-cloud lightning processes, Journal of Geophysical Research: Atmospheres, 111 (D15), doi: https://doi.org/10.1029/2005JD006879 . Westcott, N. E. (1994), Merging of Convective Clouds: Cloud Initiation, Bridging, and Subsequent Growth, Monthly Weather Review , 122 (5), 780–790, doi: 10.1175/1520-0493(1994)1222.0.Co;2 . Williams, E., et al. (2012), Resolution of the sprite polarity paradox: The role of halos, Radio Science , 47 , 2002, doi:doi: 10.1029/2011RS004794 . Wu, Y. J., et al. (2017), The leading role of atomic oxygen in the collocation of elves and hydroxyl nightglow in the low-latitude mesosphere, Journal of Geophysical Research: Space Physics, 122 (5), 5550–5567, doi: https://doi.org/10.1002/2016JA023681 . Xu, W., E. J. Zipser, C. Liu, and H. Jiang (2010), On the relationships between lightning frequency and thundercloud parameters of regional precipitation systems, Journal of Geophysical Research: Atmospheres, 115 (D12), doi: https://doi.org/10.1029/2009JD013385 . Yang, J., N. Liu, M. Sato, G. Lu, Y. Wang, and G. Feng (2018), Characteristics of Thunderstorm Structure and Lightning Activity Causing Negative and Positive Sprites, Journal of Geophysical Research: Atmospheres, 123 (15), 8190–8207, doi: https://doi.org/10.1029/2017JD026759 . Zhu, Y., et al. (2017), Evaluation of ENTLN Performance Characteristics Based on the Ground Truth Natural and Rocket-Triggered Lightning Data Acquired in Florida, Journal of Geophysical Research: Atmospheres, 122 (18), 9858–9866, doi: https://doi.org/10.1002/2017JD027270 . Zhu, Y., M. Stock, J. Lapierre, and E. DiGangi (2022), Upgrades of the Earth Networks Total Lightning Network in 2021, Remote Sensing, 14 (9), 2209. Supplementary Files 2024TAOmanuscript0125supply.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Major revision 24 Jun, 2024 Reviewers agreed at journal 11 Mar, 2024 Reviewers invited by journal 22 Feb, 2024 Editor assigned by journal 29 Jan, 2024 First submitted to journal 28 Jan, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3910591","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":274570845,"identity":"aeaedb58-7268-429b-a3a3-579aa2a53569","order_by":0,"name":"Hsun-Ya Hou","email":"","orcid":"","institution":"National Central University","correspondingAuthor":false,"prefix":"","firstName":"Hsun-Ya","middleName":"","lastName":"Hou","suffix":""},{"id":274570846,"identity":"5232248f-5deb-43c3-92e4-810506d709f4","order_by":1,"name":"chengling kuo","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+klEQVRIiWNgGAWjYDACCRBRACLZgLgCiJmZG4jQYgDTcgakhZEoLQwQLYxtIAYBLfyzm489/GJgkSfvwJYm8XFebTR/O1DLj4ptuC25cyzdWMZAotjwANsxyZnbjufOOMzYwNhz5jZOLQYSOWbSEgYSiRsb2Nukebcdy20AamFmbMOnJf8bkpY5x3LnE9aSwyb5AahlPgPbMWnehprcDYS0SNxIM5MGakzcwMyWbDnj2IHcjUAtB/H5hX9G8jPJHxV1ifPb2wxvfKipy513/vDBBz8qcGsBAWYekAsPg9kQ8gBe9UDA+ANIyDeA2XWEFI+CUTAKRsEIBAD2RVWj16xdBgAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0003-0602-6159","institution":"National Central University","correspondingAuthor":true,"prefix":"","firstName":"chengling","middleName":"","lastName":"kuo","suffix":""},{"id":274570847,"identity":"653617cb-2625-4269-b00d-69bdf1989b00","order_by":2,"name":"Rue-Ron Hsu","email":"","orcid":"","institution":"National Cheng Kung University","correspondingAuthor":false,"prefix":"","firstName":"Rue-Ron","middleName":"","lastName":"Hsu","suffix":""},{"id":274570848,"identity":"bbd96837-3b72-4048-9654-f2e19c1eee2c","order_by":3,"name":"Wei-Yu Chang","email":"","orcid":"","institution":"National Central University","correspondingAuthor":false,"prefix":"","firstName":"Wei-Yu","middleName":"","lastName":"Chang","suffix":""},{"id":274570849,"identity":"fd0c67f1-9ee3-41c3-9d55-7618f7a8acc0","order_by":4,"name":"Lou-Chuang Lee","email":"","orcid":"","institution":"Academia Sinica","correspondingAuthor":false,"prefix":"","firstName":"Lou-Chuang","middleName":"","lastName":"Lee","suffix":""}],"badges":[],"createdAt":"2024-01-30 12:46:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3910591/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3910591/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":51766759,"identity":"b24cb5b8-64a0-4d7d-b104-7c71018709b1","added_by":"auto","created_at":"2024-02-28 18:56:20","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":623107,"visible":true,"origin":"","legend":"\u003cp\u003eThe weather map at LT 20:00 on (a) 18 May, (b) 19 May, and (c) 20 May with wind data (925 mb) from \u003cstrong\u003eNAVGEM\u003c/strong\u003e (\u003cstrong\u003eNAV\u003c/strong\u003ey \u003cstrong\u003eG\u003c/strong\u003elobal \u003cstrong\u003eE\u003c/strong\u003environmental \u003cstrong\u003eM\u003c/strong\u003eodel). The corresponding flash and TLE locations in Taiwan 2018 sprite campaigns where blue and red dots indicate the locations of flash from WWLLN and TLEs’ parent lightning using WWLLN dataset on (d) 18 May, (e) 19 May, and (f) 20 May. The sectors show the scanning FOV of our camera system where a cross symbol indicates our observation site.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/d20a59f1eac4936dd60dfe62.png"},{"id":51766757,"identity":"7e774eea-9c8b-4983-9f41-36289cdadd39","added_by":"auto","created_at":"2024-02-28 18:56:20","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":396949,"visible":true,"origin":"","legend":"\u003cp\u003eThe development of a lines of MCS, their synoptic condition and temporal curves for cloud properties and flash/TLE rates. The thunderstorm evolution at time of (a) 20:00 LT for the development stage, (b) 20:30 and (c) 21:00 LT for the mature stage, and (d) 23:00 LT for the dissipating stage of the thunderstorm cell where flashes were dotted within +/- 5 minutes (orange/yellow for +CG/-CG), filled red circles for TLEs, dark blue for cloud height \u0026gt; 12 km, and gray for cloud region at \u0026gt; 10 km. The dashed circle traces the center of new cell within a radius of about 55 km. The temporal evolution of (e) maximum cloud height (km) and (f) \u0026gt; 12 km cloud area (km2) where vertical dashed lines at 20:10 LT and 21:40 LT indicate the period of mature stage, (g) radar reflectivity \u0026gt;40dB area (km2), (h) ENTLN flash rate (black dashed line for total CG where orange and yellow for +CG and –CG flash rate, respectively), (i) WWLLN CG flash rate, and (j) observed TLE number per 10 minutes.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/1f95f59e3ffc9d5b4d673dfc.jpeg"},{"id":51766756,"identity":"8759bbfd-1e95-47d8-8920-464c7013d077","added_by":"auto","created_at":"2024-02-28 18:56:19","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":320415,"visible":true,"origin":"","legend":"\u003cp\u003eThe radar reflectivity and cloud region with their cutting profile (green for the new cell moving direction and blue for vertical line at the cell center) where black symbols (+) and (o) indicate ENTLN IC/CG flashes with positive and negative polarity. The panels (a), (b) and (c) are colorized contours with maximum radar reflectivity (in units of db). We also plot the flash locations within +/- 30 seconds, and sprite locations (red dots) within +/- 30 minutes. The panels (d), (e), (f) show the cutting plane in the parallel direction of storm moving and those in vertical direction in the panels (g), (h) and (i) where the colors in contour plots indicate the radar reflectivity (in units of db).\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/7f3890f7aa892c3c6b39ae08.jpeg"},{"id":51766758,"identity":"260897bf-34dc-487a-9e5f-901736fc9c34","added_by":"auto","created_at":"2024-02-28 18:56:20","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":85745,"visible":true,"origin":"","legend":"\u003cp\u003e(a) . The correlation and scattered plots for ENTLN CG flash rate and WWLLN CG flash rate per 10 minutes’ bin, (b) the ENTLN +CG percentage, and (c) the percentage of WWLLN peak currents (\u0026gt;60, \u0026gt; 100 and \u0026gt; 200 kA) versus local time on 20 May 2018.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/168c87e5ecb12143c1e44494.png"},{"id":51766763,"identity":"6e0893ba-75be-4a68-b5d9-7748c023ab69","added_by":"auto","created_at":"2024-02-28 18:56:20","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":62959,"visible":true,"origin":"","legend":"\u003cp\u003e(a) The histogram plot for peak current (kA) for flashes at nights from LT 20:00 to 04:00 next day on May18-21, 2018 where we analyzed a total 19,380 flashes from WWLLN dataset; (b) their cumulate probability for the lognormal distribution where the purple color indicates the histogram bars of WWLLN flash and the red line indicates the fitting lognormal distribution.\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/1cf18e588171116b8704d571.png"},{"id":51766764,"identity":"155c1b05-76b4-45e1-9c0c-5427b0ea6dd8","added_by":"auto","created_at":"2024-02-28 18:56:20","extension":"jpeg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":292711,"visible":true,"origin":"","legend":"\u003cp\u003eThe histogram of TLE-associated flash (shown in blue bar chart) where the blue lines indicate the cumulative distribution function (CDF) with time window of before 300 ms and after +33 ms in comparison with red lines for the flash CDF, which indicates total flash at night in the same period in Figure 5a. The TLEs associated with high peak currents (\u0026gt; 200kA) are also listed in \u003cstrong\u003eTable 1\u003c/strong\u003e.\u003c/p\u003e","description":"","filename":"floatimage6.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/32980a11b761d06237f35f4a.jpeg"},{"id":51766762,"identity":"baad2389-01ef-4104-981b-126bbf846f6a","added_by":"auto","created_at":"2024-02-28 18:56:20","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":51268,"visible":true,"origin":"","legend":"\u003cp\u003eThe histogram plots for parent lightning’s peak currents of (a) column sprites, (b) carrot sprites and (c) tree sprites.\u003c/p\u003e","description":"","filename":"floatimage7.png","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/0fe432b5067dbdd96f7bcf6f.png"},{"id":51766761,"identity":"3f5e2af3-53ce-4e95-af7b-eccc36bf5106","added_by":"auto","created_at":"2024-02-28 18:56:20","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":42764,"visible":true,"origin":"","legend":"\u003cp\u003eThe histogram plots for parent lightning’s peak currents of (a) sprites without distinguished halo, (b) sprites with distinguished halo.\u003c/p\u003e","description":"","filename":"floatimage8.png","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/1caaed76d9207abd94773293.png"},{"id":51766766,"identity":"a79fb7fb-0e61-4f22-941f-77e008f238c7","added_by":"auto","created_at":"2024-02-28 18:56:21","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":526633,"visible":true,"origin":"","legend":"\u003cp\u003eThe recording video images for TLEs with their high-peak-current flashes at (a) 22:54:26.7413 on May 18, (b) 23:57:59.8950 on May 18, (c) 21:16:03.0469 on May 19, (d) 20:58:12.4350 on May 20, (e) 22:04:31.5199 and (f) 23:47:50.4597 on May 20 in the 2018 Taiwan campaign.\u003c/p\u003e","description":"","filename":"floatimage9.png","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/d3c920b5f30154d7e27e6081.png"},{"id":51768066,"identity":"0aa76f98-8d3e-4a48-9c70-64af4f5a6e24","added_by":"auto","created_at":"2024-02-28 19:04:21","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2058319,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/225aafb6-b61b-4790-8154-f2e0854f1d9c.pdf"},{"id":51766760,"identity":"77abda6d-452a-475c-af10-70e69ab8788d","added_by":"auto","created_at":"2024-02-28 18:56:20","extension":"docx","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":625105,"visible":true,"origin":"","legend":"","description":"","filename":"2024TAOmanuscript0125supply.docx","url":"https://assets-eu.researchsquare.com/files/rs-3910591/v1/855f9009db01007f32b6901d.docx"}],"financialInterests":"","formattedTitle":"Case study on sprite and lightning activities associated with the cell life cycle in a mesoscale convective system","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eThe meteorological studies on a mesoscale convective system (MCS) associated transient luminous events (TLEs) improve our understanding of TLEs production and relevant meteorological conditions. Lyons et al. studied the MCS meteorological conditions and found that the generation of TLEs is related to substantial convection and laterally stratiform rain areas (Lyons, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). Lang et al. (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2010\u003c/span\u003e) also furtherly investigated that sprite production is associated with a convective-initiated flash region, or a stratiform-initiated flash region. They pointed out another possible scenario of sprite production in the cell mergers in thunderstorms (Lang et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). However, the relationship between TLE production and MCS morphology (e.g., convection or stratiform regions) is still complex. Here, we present our observational results of the Taiwan Lulin 2018 campaign. The observation provides an opportunity to study the TLE production associated with the cell lifetime (development, mature and dissipating processes) of MCS. Unlike previous reports on complex MCS meteorological environments (Lang et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2016\u003c/span\u003e), our case study of the cell lifetime in the MCS will help to resolve the complex MCS environment associated with TLE production.\u003c/p\u003e \u003cp\u003eA line of MCS in summer near Taiwan could produces favorable meteorological conditions for cloud electrification, including vigorous convection and heavy rainfall especially for East Asian Summer Monsooon (Chen, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e1983\u003c/span\u003e; Chen et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2006\u003c/span\u003e; Du et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Parker and Johnson, \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2000\u003c/span\u003e). The accompanying vigorous development stage of MCS can in-crease lightning activity in observation and modeling results (Chen et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Due to the large-scale lifting and the moist southwesterly low-level jet (Chen et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2006\u003c/span\u003e), the long-sustained MCS system may also favor high lightning activity (Xu et al., \u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e2010\u003c/span\u003e) and TLE occurrences in this study. The Taiwan Lulin 2018 campaign observed TLEs include sprites, sprite halo, and elves where sprites/sprite halo are dominated (284 events) and elves have only 3 events. Lightning with high peak current is one of the essential indicators for intense sprite-producing thunderstorms (Pizzuti et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). High peak cur-rent or impulse charge moment change in lightning also can cause sprite halos (Frey et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2007\u003c/span\u003e; Kuo et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021a\u003c/span\u003e; Kuo et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2021b\u003c/span\u003e; Lu et al., \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Williams et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2012\u003c/span\u003e) and elves (Kolmašov\u0026aacute; et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Kuo et al., \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021a\u003c/span\u003e; Kuo et al., \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2012\u003c/span\u003e; \u003cem\u003eParra‒Rojas et al.\u003c/em\u003e, 2013; P\u0026eacute;rez-Invern\u0026oacute;n et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2018a\u003c/span\u003e; P\u0026eacute;rez-Invern\u0026oacute;n et al., \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2018b\u003c/span\u003e). The flash peak current is available from the global lightning network. In this study, we analyzed these sprite halos with their parent flashes with high-peak-current (\u0026gt;\u0026thinsp;200 kA) from the statistical results of the Taiwan Lulin 2018 campaign. The TLEs with their parent flashes and high peak currents\u0026thinsp;\u0026gt;\u0026thinsp;200 kA were investigated, and all have common optical features of sprite halos and clusters of sprites structures.\u003c/p\u003e"},{"header":"2. Taiwan Lulin 2018 campaign","content":"\u003cp\u003eThe Lulin observatory (120◦ 52\u0026rsquo; 25\" E, 23◦ 28\u0026rsquo; 07\"N) at an altitude of 2,862 m was chosen for the Taiwan campaign in 2018 for its high transparent atmospheric conditions. The maximum distance of our observed TLE can be up to 800 km. We utilized a high-speed camera system in the Taiwan Lulin 2018 campaign (Kuo et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2021b\u003c/span\u003e). The observation system consists of two cameras: a focal length 20 mm high-speed camera bore-sighted with a 12 mm camera and the low-light-level monochrome CCD (Watec 910HX). In this study, we used the observed TLEs by the low-light-level CCD system to investigate the meteorology environment of MCS with producing TLE flashes. Using the GPS timestamp, its time accuracy with 0.1 milliseconds (ms) can precisely deter-mine TLE\u0026rsquo;s parent lightning. The FOV of the low-light-level CCD with 30 fps is about 25.8 deg in horizontal. The camera system was auto-recorded by software in the computer. The camera system is manually operated by observers to trace the moving position of the new cell in the MCS system with flashes. The scanning angle of the camera system is about 90 deg, as shown in sector regions in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e where an arc of the sec-tor region indicates the farthest observation distance of 800 km. Although we cannot rule out the possibility of missing TLEs, the relationship between TLEs and flash activity was definitely existed but could be underestimated.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eOn 18\u0026ndash;20 May 2018, a line of MCS accompanied by a cold front system occurred in our observation region during the early Meiyu season in East Asia. For the observed region, the Fujian climate report also documented the deep convection system with a hail diameter 10\u0026ndash;20 mm and lasting 2 minutes. We analyzed the cell area and cloud top temperature from Taiwan CWB (Central Weather Bureau) processing data using Japan Meteorological Agency Himawari satellite to trace the development conditions within a single cell of the MCS. We derived their cloud top height from using a back-ground temperature profile from the closest balloon-sounding data where the balloon-launching site is only distanced within 200 km in our studies. Besides, we analyzed radar reflectivity data from Taiwan weather radar network (S-band Doppler single-polarization radars). The maximum radar reflectivity indicates the heavy precipitation region in the thunderstorm. Drawing out the maximum reflectivity associated with flash/TLEs helps us to recognize the spatial relationship between cell development and flash/TLEs activity, also seeing Sections \u003cspan refid=\"Sec4\" class=\"InternalRef\"\u003e3.1\u003c/span\u003e and \u003cspan refid=\"Sec5\" class=\"InternalRef\"\u003e3.2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003eWe analyzed the flash activity in the MCS associated with TLE using Earth Networks Total Lightning Network (ENTLN) dataset. The ENTLN uses the time-of-arrival detection methodology with GPS technology and sophisticated algorithms to accurately locate and classify lightning types. A sensor includes wideband electrical field recorders (frequency ranging from 1HZ to 12MHZ), a GPS receiver, a nano-second GPS-based timing circuit, a digital signal processor (DSP), onboard storage and internet communication equipment. As a result of the advanced predictive abilities and global deployment of ENTLN, it has the potential to significantly improve severe weather warning times over radar and other technologies (Bui et al., \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Zhu et al., \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Zhu et al., \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Lightning also helps us to study the electrical activity of MCS.\u003c/p\u003e \u003cp\u003eHowever, ENTLN data were available for close regions of our TLE observation on May 20. Besides, the radar reflectivity data of a thunderstorm system from the Weather dataset of Taiwan CWB is limited only for the close observation region. For the far region of our observation on 18\u0026ndash;19 May, we used WWLLN (World Wide Lightning Lo-cation Network) lightning data. The WWLLN is a real-time, worldwide, ground-based network operated by the University of Washington that can detect extreme lightning events occurring anywhere in the world. The WWLLN network's purpose was to achieve global detection with a location accuracy of fewer than 10 km (Rodger et al., \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). The WWLLN receivers operate in the VLF band and detect the lightning wave packet that propagates in the region between the Earth and the lower ionosphere. These wave packets propagate in particular waveguide modes (TE, TM or TEM), which effectively obscure the polarity of the parent lightning strokes (Abarca et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2010\u003c/span\u003e; Hutchins et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2012a\u003c/span\u003e; Hutchins et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2012b\u003c/span\u003e; Jacobson et al., \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Rodger et al., \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). Hence, the WWLLN dataset provide the peak current and the corresponding location of TLEs\u0026rsquo; parent lightning but without their polarity.\u003c/p\u003e"},{"header":"3. Observation Results","content":"\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e3.1. Thunderstorm and lightning activity associated with TLEs on May 20\u003c/h2\u003e \u003cp\u003eThree distinct periods for the lightning evolution inside the observed MCS on May 20, 2018 are categorized as: (1) the development stage (before 20:00 LT), (2) the mature stage (20:10\u0026ndash;21:40 LT), and (3) the dissipating stage (21:40 LT -). Figures\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea-\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ed shows four characteristic snapshots at 20:00, 20:30, 21:00 and 23:00 LT for the development stage, first observed TLE, the mature stage, and the dissipating stage, respectively. We can observe the merging of a new cell (dashed-line circle) and an old cell of the line of MCSs in Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea-\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ed. Within the merging of two cells, the new cell expanded their cloud region while the old cells shrank the cloud area. The interaction process between two cells were also accompanied by the first observed TLE in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb. In the mature stage of the MCS, observed TLEs were scattered in the stratiform region of the new cell. The results were consistent with previous TLE studies (Lang et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Lang et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2010\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe criteria of the three stages are defined based on the maximum cloud top height. Figures\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ee-\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ej show the temporal curves for cloud properties associated with ENTLN/WWLLN flash and TLE activities. The updraft in the convective region in-creased the cloud height to a maximum value of 16 km at ~\u0026thinsp;20:10 LT, shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ee. The characteristic time at 20:10 LT corresponds to the transition from the development sage to the mature stage. That implies that the concurrence of updraft and downdraft in the convective region stopped gaining cloud top height for the mature stage. After 20:10 LT, the downdraft activity inside the cell may cause a slight down-ward trend of the cloud top height. Two local maximum values of ~\u0026thinsp;18 km imply small-scale updrafts in the mature stage. After 21:40 LT, the cloud height gradually decreased less than 16 km. An updraft ceases, and the downdraft is dominated for the dissipating stage. The lower cloud height explains that the cell developed into its dissipating phase.\u003c/p\u003e \u003cp\u003eIn Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ef and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eg, the new cell of the thunderstorm had a maximum area of cloud (9.3x10\u003csup\u003e3\u003c/sup\u003e km\u003csup\u003e2\u003c/sup\u003e) in the dissipating stage at 22:30 LT while their maximum radar area (\u0026gt;\u0026thinsp;40 dB) is 2.3\u0026times;10\u003csup\u003e3\u003c/sup\u003e km\u003csup\u003e2\u003c/sup\u003e at 22:20 LT. The dissipating state of the cell had their maximum values of radar reflectivity area (\u0026gt;\u0026thinsp;40 dB) and cloud area (h\u0026thinsp;\u0026gt;\u0026thinsp;12 km) with ~\u0026thinsp;90 minutes delay after a peak time (20:50 LT) of ENTLN CG flash rate 115.1 min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e where 95.1 min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e for \u0026ndash;CGs and 20.0 min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e for +\u0026thinsp;CG), respectively in yellow and orange lines of Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eh and WWLLN CG flash rate 26.6 min\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e in green line of Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ei. In Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ej, two distinct periods of TLE activity occurs from 20:30 to 21:30 LT and after 22:50 LT, corresponding to the mature stage and the dissipating stage of lightning activity. We studied the radar reflectivity intensity for TLE\u0026rsquo;s parent lightning locations with considering possible displacement 10 km within TLEs (van der Velde et al., \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). For the period of the mature stage, the maximum reflectivity was 44\u0026thinsp;\u0026plusmn;\u0026thinsp;8 dB while a lower value of 31\u0026thinsp;\u0026plusmn;\u0026thinsp;6 dB for the dissipating state. In previous studies, the average reflectivity generally ranges between 30 to 35 dB at a distance of 10 km near TLEs\u0026rsquo; parent lightning (van der Velde et al., \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2006\u003c/span\u003e) while TLE associated\u0026thinsp;+\u0026thinsp;CG located in the stratiform region of the MCS with a radar reflectivity between 25\u0026ndash;35 dB (Pan et al., \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Besides, recent report also found the TLEs\u0026rsquo; parent lightning in the convective region and stratiform region of the MCS (Suzuki et al., \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) while previous studies only observed TLE above the stratiform region of MCS (Suzuki et al., \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e2022\u003c/span\u003e and references therein; Yang et al., \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e3.2. Observed TLEs during the cell merging and the dissipation of a thunderstorm system\u003c/h2\u003e \u003cp\u003eCell merging is one of important processes to intensify the convective system (Westcott, \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e1994\u003c/span\u003e). Lu et al. (Lu et al., \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) investigate the cell merging and corresponding lightning activity using observation and simulation. Their results support that cell merging can enhance the lightning activity. The strong updraft via the horizontal transport of ice-phase particles may increases the collision rate and enhance the electrification. The cloud bridge between two merging cell is one of lightning surged region (Lu et al., \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). In \u003cb\u003eFigures A (a) and A (b)\u003c/b\u003e of supplement materials, we can identify the newly detected flashes (red dashed circles) inside the cloud bridge between old and new cells on 20:10 LT, May 20. From 20:10 LT to 21:00 LT, the cloud bridge in-creased its size, and finally merged into the new cell after 21:00 LT.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e shows the maximum radar reflectivity and their vertical profiles at three characteristic times (development, mature and dissipating) where the maximum radar reflectivity is overlaid with ENTLN flashes in Figs.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ea, \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb, and \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ec. Their cutting profiles of radar reflectivity along the cell moving direction in Figs.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ed, \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ee, and \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ef and perpendicular to the moving line in Figs.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eg, \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eh, and \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ei. The ENTLN flashes are highly correlated in spatial distribution with the high reflectivity (\u0026gt;\u0026thinsp;40dB) in the development and the mature stage of the thunderstorm in the projected area of Figs.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ea, and \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb. But, at the dissipating stage in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ec, a lower number of flashes was widely distributed above the radar reflectivity\u0026thinsp;\u0026gt;\u0026thinsp;30 dB.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb, we show an interesting case of merging two lightning cluster in a squall line system. The merging of two charge systems of the new cell and the old cell in a squall line may explain the increases of our observed TLE events. Found the observed number of TLEs in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ej, the first sudden increase happened from 20:10 LT to 21:00 LT during the cell merging of a thunderstorm system. The TLEs\u0026rsquo; parent lightning scattered in the new cell and the merging area, shown in red dots of Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb. From 20:10 to 21:40 LT, the merged convective system has more flash numbers, while the old cell and new cell of the MCS produce more TLEs and flash rates than the later time in dissipating period after 21:30 LT.\u003c/p\u003e \u003cp\u003eIn a line of MCS, the balance between convectively-induced low-level cold pool strength and depth under heavy rain and the ambient low-level wind shear may trigger new cells and could provide the atmospheric environment with strong convection. The intensity of the cell may be related with their high flash rate. Besides, the TLEs\u0026rsquo; parent flashes were located in the cloud bridge and the new cell during the cell merging, as shown by red dots in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb. Our observation supports the flash and TLEs\u0026rsquo; parent flashes in the MCS convective region, especially during cell merging process.\u003c/p\u003e \u003cp\u003eThe measured flash rates had their peak values in yellow and orange lines in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eh for ENTLN\u0026thinsp;+\u0026thinsp;CG/-CG, respectively, and green line in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ei for WWLLN CG. The ENTLN/WWLLN flash rate in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eh\u003cb\u003e/2i\u003c/b\u003e and TLE rate in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ej reach their maximum values around 20:50 LT. That may imply that the cell merging between 20:10 to 21:40 LT not only increases the probability of flashes but ENTLN\u0026thinsp;+\u0026thinsp;CG per-centage also boost the TLE numbers in this case study.\u003c/p\u003e \u003cp\u003eDuring the thunderstorm dissipating stage, the CG flash rates decreased from 104.5 min-1 at 21:00 LT to 9.0 min-1 at 23:00 LT, while the TLE rate was constantly maintained at 1\u0026ndash;2 events per ten minutes. The +\u0026thinsp;CG in the stratiform of MCS (Lang et al., \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2004\u003c/span\u003e) could provide the electrical environment of producing TLEs (Lang et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Lang et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). Besides, the ENTLN measured +/- IC flash of the dissipating thunderstorm also decreases their height. After 23:20 LT, TLE activity was enhanced again. We will furtherly discuss it in Section \u003cspan refid=\"Sec7\" class=\"InternalRef\"\u003e4.1\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e"},{"header":"4. Discussions","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e4.1. The sprite activity associated with ENTLN\u0026thinsp;+\u0026thinsp;CG percentage and WWLLN high peak current flash ratios\u003c/h2\u003e \u003cp\u003eTo clarify the correlations between TLEs and lightning activity in mature and dissipating stages, we analyzed the ENTLN\u0026thinsp;+\u0026thinsp;CG percentage and the WWLLN high peak current percentage in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. The +\u0026thinsp;CG percentage could be used to investigate the probability of producing TLE flash since greater than 99.9% sprites are produced by +\u0026thinsp;CG flash (Chen et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). High peak current lightning may favor halo and sprite halo occurrences (Williams et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2012\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea, we consider the ENTLN CG flash rate (\u003cem\u003eR\u003c/em\u003e\u003csub\u003e\u003cem\u003eENTLN\u003c/em\u003e\u003c/sub\u003e) and WWLLN CG flash rate (\u003cem\u003eR\u003c/em\u003e\u003csub\u003e\u003cem\u003eWWLLN\u003c/em\u003e\u003c/sub\u003e) per 10 minutes\u0026rsquo; bin. A scatter plot in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea shows the ENTLN and WWLLN CG flash rate per 10 minutes in Figs.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ed and \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ee. Their linear relationship can be formulated by \u003cb\u003eR\u003c/b\u003e\u003csub\u003e\u003cb\u003eWWLLN\u003c/b\u003e\u003c/sub\u003e \u003cb\u003e= 0.2105 \u0026times; R\u003c/b\u003e\u003csub\u003e\u003cb\u003eENTLN\u003c/b\u003e\u003c/sub\u003e \u003cb\u003e+ 0.3414\u003c/b\u003e with a correlation coefficient 0.9663. Hence, the percentage calculation for +\u0026thinsp;CG and high peak current won\u0026rsquo;t be varied by detected flash rates. Hence, the detected flash rates of ENTLN and WWLLN should have a linear relationship.\u003c/p\u003e \u003cp\u003eWe examined two indicators (ENTLN\u0026thinsp;+\u0026thinsp;CG percentage and WWLLN large peak current percentage) per 10 minutes\u0026rsquo; bin. In Figs.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ec, we testify the ENTLN\u0026thinsp;+\u0026thinsp;CG percentage and WWLLN large peak current percentage (the percentages of peak currents I\u0026thinsp;\u0026gt;\u0026thinsp;100kA and I\u0026thinsp;\u0026gt;\u0026thinsp;60kA) for TLE numbers per 10 minutes. The flash peak current 60 kA is required minimum current for elves emissions (Barrington-Leigh and Inan, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e1999\u003c/span\u003e) and 100 kA is proposed by large peak current in work of (Pizzuti et al., \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). In addition, positive or negative flashes with peak current\u0026thinsp;\u0026gt;\u0026thinsp;50 kA and a total charge moment\u0026thinsp;\u0026gt;\u0026thinsp;500 C-km may explain the occurrence of diffuse halo emissions (Williams et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2012\u003c/span\u003e). Figure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ej shows two active periods of TLEs during 20:25\u0026thinsp;\u0026minus;\u0026thinsp;21:25 LT and after 21:55 LT. The first TLE activity during 20:25\u0026thinsp;\u0026minus;\u0026thinsp;21:25 LT corresponded to a surge of the ENTLN\u0026thinsp;+\u0026thinsp;CG percentage in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb, where the ENTLN\u0026thinsp;+\u0026thinsp;CG percentage increased from 6.8% at 19:50 LT to 18.7% at 20:40 LT, and decreased to 15.8% at 21:30 LT. After 21:40 LT, the CG rate decreased but the observed TLEs had 1\u0026ndash;2 events per 10 minutes after 21:55 LT in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ej. After 23:15 LT, observed TLEs increased to 3 events per 10 minutes. In Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb, the ENTLN\u0026thinsp;+\u0026thinsp;CG percentage jumped to its peak value of 31.3% at 23:20 LT while the WWLLN large peak current (I\u0026thinsp;\u0026gt;\u0026thinsp;100kA) has its local peaks at 23:20 LT, especially for second TLEs activity. The percentage of higher peak current, e.g., I\u0026thinsp;\u0026gt;\u0026thinsp;200kA, is expected as similar to the plot of I\u0026thinsp;\u0026gt;\u0026thinsp;100 kA, but is not sensitive as the percentage of I\u0026thinsp;\u0026gt;\u0026thinsp;100kA.\u003c/p\u003e \u003cp\u003eMost \u0026ndash;CG cannot have both of large peak current and long continuing current to favor sprite production (Saba et al., \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). Most\u0026thinsp;+\u0026thinsp;CG with continuing current and high charge transferred may associated with the sprite and sprite halos (Williams et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2012\u003c/span\u003e). In our case study, the mature thunderstorm stage with a high\u0026thinsp;+\u0026thinsp;CG rate may favor in the sprite production. In addition, a high peak current flash may cause the sprite halos in our case study of thunderstorm dissipating stage. Pizzuti et al. (\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) found that intense lightning discharge with large peak current\u0026thinsp;\u0026gt;\u0026thinsp;100 kA, although not directly related to the total amount of charge transferred. Therefore, a high\u0026thinsp;+\u0026thinsp;CG rate with high peak currents may contribute the probability of sprite halo and sprites in our case study. We will discuss it on WWLLN measured peak currents between TLEs\u0026rsquo; parent flashes and flashes without observed TLEs in next session.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e4.2. Sprite halos produced by high peak current flashes\u003c/h2\u003e \u003cp\u003eLyons et al. (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e1998\u003c/span\u003e) reported the +\u0026thinsp;CG associated with sprites typically have large peak current. Their study indicates that the +\u0026thinsp;CG peak current associated with sprites averaged 81 kA versus 30 kA for other\u0026thinsp;+\u0026thinsp;CG in the same MCS. Large peak current -CG may cause the pure halo (Frey et al., \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2007\u003c/span\u003e; Williams et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2012\u003c/span\u003e), elves (Barrington-Leigh and Inan, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e1999\u003c/span\u003e; Kuo et al., \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2012\u003c/span\u003e; P\u0026eacute;rez-Invern\u0026oacute;n et al., \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2018b\u003c/span\u003e; Wu et al., \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2017\u003c/span\u003e) and sprites (Chen et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). Hence, we are interested to compare the probability of flash peak current associated with sprite in the MCS on May18-21, 2018, especially for a long-sustained weather system of the East Asian Summer Monsoon. First, we show the +/-CG peak current probability distribution in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e. We assume that the +\u0026thinsp;CG percentage of total\u0026thinsp;+\u0026thinsp;CG/-CG are almost equal since +\u0026thinsp;CG is roughly 10% of total flash. Second, we compare the TLE associated peak current probability distribution and the total flash in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe peak current and time of flash associated with selected sprites in 2018 Taiwan campaign.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDate\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eEvent Time\u003csup\u003e1\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eFlash time\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eI(kA)\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ea\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMay 18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e22:54:26.7413\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e22:54:26.7094\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eb\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMay 18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e23:57:59.8950\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e23:57:59.8690\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e244\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ec\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMay 19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e21:16:03.0469\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e21:16:03.0229\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e357\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMay 20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e20:58:12.4350\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e20:58:12.4054\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e311\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ee\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMay 20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e22:04:31.5199\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e22:04:31.4848\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e261\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ef\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMay 20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e23:47:50.4597\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e23:47:50.4091\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e267\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003e1\u003c/sup\u003e GPS timetag time (LT) from TLE observation;\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003e2\u003c/sup\u003e WWLLN flash time (LT);\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003csup\u003e3\u003c/sup\u003e WWLLN measured peak current of parent lightning in units of kilo-ampere (kA)\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ea shows the histogram plots for the WWLLN measured peak current in units of kA at nights from LT 20:00 to 04:00 next day on May18-21, 2018. In these observation regions, we analyzed a total 19,380 flashes from the WWLLN dataset. The median of the peak currents of flashes in our observation region is 45.2 kA. Hence, for the probability function of their peak currents in this case study, we consider the lognormal distribution as a probability density function \u003cb\u003eP\u003c/b\u003e\u003csub\u003e\u003cb\u003elog\u003c/b\u003e\u003c/sub\u003e\u003cb\u003e(I)\u003c/b\u003e for the best fitting function for peak current \u003cb\u003eI\u003c/b\u003e as one of best fitting distribution function (Cummer et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2013\u003c/span\u003e),\u003cdiv id=\"Equ1\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ1\" name=\"EquationSource\"\u003e\n$${\\text{P}}_{log}\\left(\\text{I}|{\\mu }, {\\sigma }\\right)=\\frac{1}{\\text{I}{\\sigma }\\sqrt{2\\pi }}exp\\left\\{\\frac{-{\\left(\\text{l}\\text{o}\\text{g}\\left(I\\right)-{\\mu }\\right)}^{2}}{2{\\sigma }^{2}}\\right\\}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e1\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewhere the mean \u0026micro; and variance σ are fitting values for lognormal distribution. Shown with all flash at nights in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eb, the cumulative probability at 50%, 75%, and 95% corresponds to peak currents 47.6 kA, 66.0 kA, and 105.4 kA, respectively.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eb shows the cumulative probability for flash peak current where cumulative probability at 50% corresponds to peak current 47.6 kA. In comparison with 2010 WWLLN\u0026rsquo;s results, the cumulative probability of 50% indicate the flash peak current 42 kA (Hutchins et al., \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2012a\u003c/span\u003e). Our results show the cumulative probability\u0026thinsp;~\u0026thinsp;90% for flash peak current (\u0026lt;\u0026thinsp;100 kA), also shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003eb. According to the parameterization studies of TLEs based on WWLLN dataset in 2016, the WWLLN flash peak currents (\u0026lt;\u0026thinsp;100 kA) account for 86% (Evtushenko et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). But these CGs with peak current 100\u0026ndash;200 kA is quite important for triggering sprites, about 11% of flashes in 2016 WWLLN dataset (Evtushenko et al., \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) where CGs with \u0026gt;\u0026thinsp;200 kA is fewer (3%). It is noted that the stroke power and related peak current measured by WWLLN has substantial seasonal and interannual variability and also depends on the number of active WWLLN stations. For example, for the median stroke power, there is a near-continuous decrease from 2013 to the end of 2020 (Kaplan and Lau, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e shows WWLLN peak currents associated with observed TLEs within a time window (before 300 ms and after +\u0026thinsp;33 ms). For that time window, flash peak cur-rents have a cumulative probability of 50%, 75%, and 95% for 81.5 kA, 147.8 kA, and 252 kA, respectively. The TLE-associated flashes with peak currents\u0026thinsp;\u0026gt;\u0026thinsp;100 kA and 200 kA have the cumulative probability of 66.2% and 91.7%, respectively. Our results show that ~\u0026thinsp;9.3% of TLEs\u0026rsquo; parent flashes have TLE\u0026rsquo;s parent lightning peak currents greater than 200 kA.\u003c/p\u003e \u003cp\u003eFor studies on parent lightning peak currents for sprites, we categorized our observed sprites with WWLLN measured peak currents as the group for column sprites, carrot sprites and tree sprites (B\u0026oacute;r, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). We avoid to misclassify events between wishbone, angel and tree sprites since the spatial resolution of some recorded images are too low. In our study, we consider the major morphological classes: column sprites, carrot sprites and tree sprites. The sprite event was distinguished based on the time difference of \u0026gt;\u0026thinsp;2 frames and the spatial displacement of \u0026gt;\u0026thinsp;50 km (B\u0026oacute;r, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). We analyzed 144 events out of 284 recorded events after we excluded the unclassified events and no-identified peak current in a time window of before 300 ms and after +\u0026thinsp;33 ms. The number for column sprites, carrot sprites and tree sprites are 11, 94, and 33 events, respectively. The peak currents of their parent lightning are shown in histogram plots in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e. Figure\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e also show the peak current histogram for sprites without halo or with halos where halo was identified as the intensity which is greater than 3σ of background signals where σ is the standard deviation or their disk-shape halo emissions in the recorded images. The results show the tendency that higher peak current for sprites with halos have the larger peak current.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAlthough energetic positive CGs with large charge moment change (CMC) are known for their capability for producing sprites (Cummer and Inan, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e1997\u003c/span\u003e; Kohlmann et al., \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Lu et al., \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2009\u003c/span\u003e; Mlynarczyk et al., \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2015\u003c/span\u003e), this study also suggest that high peak current of TLEs\u0026rsquo; parent lightning would be a good indicator for TLEs, especially for sprite halo. Their impulse peak current radiates the inducing electric field and causes the sprite halo emission (Kuo et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2021b\u003c/span\u003e; P\u0026eacute;rez-Invern\u0026oacute;n et al., \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2018a\u003c/span\u003e; P\u0026eacute;rez-Invern\u0026oacute;n et al., \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2018b\u003c/span\u003e). Cummer et al. (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2013\u003c/span\u003e) estimated a minimum value of iCMC (\u0026gt;\u0026thinsp;300 C-km) for +\u0026thinsp;CG and iCMC (\u0026gt;\u0026thinsp;500 C-km) for \u0026ndash;CG where iCMC indicates the total charge moment change over the first 2 ms of the lightning stroke (Cummer et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). Positive or negative flashes with peak current\u0026thinsp;\u0026gt;\u0026thinsp;50 kA and a total charge moment\u0026thinsp;\u0026gt;\u0026thinsp;500 C-km may explain the occurrence of diffuse halo emissions (Williams et al., \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2012\u003c/span\u003e). Figure\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e shows six TLE events with disk-shape halo emissions and their parent lightning with high-peak-current (\u0026gt;\u0026thinsp;200 kA) listed in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The optical features of sprites with their high-peak-current parent lightning are: (1) visible halos, (2) column sprites or carrot sprites, (3) clusters sprites or so-called jellyfish sprites. In Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003ec, a sprite event with a peak current 357 kA has a large cluster of carrot sprites with a visible halo emission, also called by jellyfish sprite.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"5. Summary","content":"\u003cp\u003eThe MCS evolution was traced and studied using meteorological/lightning/sprites analyses. We show three time periods for lightning activity inside the sprite-producing thunderstorm, their synoptic condition, and temporal curves for cloud properties (cloud area, maximum cloud height, radar reflectivity) and ENTLN/WWLLN flash rates and sprite rates. We analyzed the relationship between the meteorological condition of MCS, flash and TLE activities at night on May 20, 2018. Three time periods (20:00/21:00/23:00 LT) indicate the significant stages for MCS evolution using lightning activity: (1) development stage (before 20:00 LT), (2) mature stage (20:10\u0026ndash;21:40 LT), and (3) dissipating stage (after 21:40 LT), respectively. First observed sprite occurred at 20:30 during the merging period of the MCS evolution. Another increase of TLE was also found in the decaying stage of the MCS.\u003c/p\u003e \u003cp\u003eThe main findings of our observation are summarized as follows:\u003c/p\u003e \u003cp\u003e(1) The Mei-Yu season in May-June is one of the most severe weather phenomena with heavy rainfall in the early-summer rainy season over east-south Asia. A line of mesoscale convective systems (MCSs) provides strong updraft and severe lightning, and produces favorable weather conditions for high flash rates and sprite occurrences.\u003c/p\u003e \u003cp\u003e(2) The observation supports the previous studies of transient luminous events associated with the mature stage and the dissipating stage of a thunderstorm system, especially for first TLE during cell-merging on 20:10\u0026ndash;21:00 LT (Lang et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Lang et al., \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2010\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e(3) The parent flash of TLEs had larger peak current for TLEs with distinguished halo emissions.\u003c/p\u003e \u003cp\u003e(4) The optical features of sprites with their parent flash of peak current\u0026thinsp;\u0026gt;\u0026thinsp;200 kA are: a visible halo, column sprites or carrot sprites, and clusters of sprites.\u003c/p\u003e \u003cp\u003e(5) The peak current of TLEs\u0026rsquo; parent lightning could be a good indicator for TLE, especially for sprite halo.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e: Methodology and formal analysis H. Y. H and C.-L. K.; writing\u0026mdash;original draft preparation, H. Y. H, C.-L. K and R.-R. H.; radar data provided, C.-Y. H.; supervision, R.-R. H. and L.-C. L. All authors have read and agreed to the published version of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e: This research was funded by MOST 111-2111-M-008-008, MOST 110-2111-M-008-007, MOST 109-2111-M-008-006 and MOST 108-2111-M-008-005 funded by Ministry of Science and Technology of Taiwan.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e: The authors would like to thank the service from Ministry of Science and Technology \u0026amp; Chinese Culture University, Data Bank for Atmospheric and Hydrologic Research. They would like to thank Prof. Bob Holzworth (WWLLN) for providing the lightning data for this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest\u003c/strong\u003e: The authors declare no conflict of interest.\u003cbr\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAbarca, S. F., K. L. Corbosiero, and T. J. Galarneau Jr. (2010), An evaluation of the Worldwide Lightning Location Network (WWLLN) using the National Lightning Detection Network (NLDN) as ground truth, Journal of Geophysical Research: Atmospheres, \u003cem\u003e115\u003c/em\u003e(D18), doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2009JD013411\u003c/span\u003e\u003cspan address=\"10.1029/2009JD013411\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarrington-Leigh, C. P., and U. S. Inan (1999), Elves triggered by positive and negative lightning discharges, Geophysical Research Letters, \u003cem\u003e26\u003c/em\u003e, 683\u0026ndash;686.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eB\u0026oacute;r, J. (2013), Optically perceptible characteristics of sprites observed in Central Europe in 2007\u0026ndash;2009, Journal of Atmospheric and Solar-Terrestrial Physics, \u003cem\u003e92\u003c/em\u003e, 151\u0026ndash;177, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jastp.2012.10.008\u003c/span\u003e\u003cspan address=\"10.1016/j.jastp.2012.10.008\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBui, V., L.-C. Chang, and S. Heckman (2015), \u003cem\u003eA Performance Study of Earth Networks Total Lighting Network (ENTLN) and Worldwide Lightning Location Network (WWLLN)\u003c/em\u003e, 386\u0026ndash;391 pp., doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1109/CSCI.2015.120\u003c/span\u003e\u003cspan address=\"10.1109/CSCI.2015.120\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChen, A. B.-C., H. Chen, C.-W. Chuang, S. A. Cummer, G. Lu, H.-K. Fang, H.-T. Su, and R.-R. Hsu (2019), On negative Sprites and the Polarity Paradox, Geophysical Research Letters, \u003cem\u003e46\u003c/em\u003e(16), 9370\u0026ndash;9378, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2019GL083804\u003c/span\u003e\u003cspan address=\"10.1029/2019GL083804\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChen, T. J. (1983), Observational Aspects of the Mei-Yu Phenomenon in Subtropical China, Journal of the Meteorological Society of Japan. Ser. II, \u003cem\u003e61\u003c/em\u003e(2), 306\u0026ndash;312, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.2151/jmsj1965.61.2_306\u003c/span\u003e\u003cspan address=\"10.2151/jmsj1965.61.2_306\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChen, T. J., C. C. Wang, and L. F. Lin (2006), A Diagnostic Study of a Retreating Mei-Yu Front and the Accompanying Low-Level Jet Formation and Intensification, Monthly Weather Review, \u003cem\u003e134\u003c/em\u003e(3), 874\u0026ndash;896, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1175/mwr3099.1\u003c/span\u003e\u003cspan address=\"10.1175/mwr3099.1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChen, Z., X. Qie, Y. Yair, D. Liu, X. Xiao, D. Wang, and S. Yuan (2020), Electrical evolution of a rapidly developing MCS during its vigorous vertical growth phase, Atmospheric Research, \u003cem\u003e246\u003c/em\u003e, 105201, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.atmosres.2020.105201\u003c/span\u003e\u003cspan address=\"10.1016/j.atmosres.2020.105201\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCummer, S. A., and U. S. Inan (1997), Measurement of charge transfer in sprite-producing lightning using ELF radio atmospherics, Geophysical Research Letters, \u003cem\u003e24\u003c/em\u003e(14), 1731\u0026ndash;1734, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/97GL51791\u003c/span\u003e\u003cspan address=\"10.1029/97GL51791\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCummer, S. A., W. A. Lyons, and M. A. Stanley (2013), Three years of lightning impulse charge moment change measurements in the United States, Journal of Geophysical Research: Atmospheres, \u003cem\u003e118\u003c/em\u003e(11), 5176\u0026ndash;5189, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/jgrd.50442\u003c/span\u003e\u003cspan address=\"10.1002/jgrd.50442\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDu, Y., Z. Q. Xie, and Q. Miao (2020), Spatial Scales of Heavy Meiyu Precipitation Events in Eastern China and Associated Atmospheric Processes, \u003cem\u003eGeophysical Research Letters\u003c/em\u003e, \u003cem\u003e47\u003c/em\u003e(11), e2020GL087086, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2020GL087086\u003c/span\u003e\u003cspan address=\"10.1029/2020GL087086\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEvtushenko, A., N. Ilin, and E. Svechnikova (2022), Parameterization and global distribution of sprites based on the WWLLN data, Atmospheric Research, \u003cem\u003e276\u003c/em\u003e, 106272, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.atmosres.2022.106272\u003c/span\u003e\u003cspan address=\"10.1016/j.atmosres.2022.106272\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFrey, H. U., et al. (2007), Halos generated by negative cloud-to-ground lightning, Geophysical Research Letters, \u003cem\u003e34\u003c/em\u003e(18), L18801, doi:doi: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1029/2007gl030908\u003c/span\u003e\u003cspan address=\"10.1029/2007gl030908\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHutchins, M. L., R. H. Holzworth, J. B. Brundell, and C. J. Rodger (2012a), Relative detection efficiency of the World Wide Lightning Location Network, Radio Science, \u003cem\u003e47\u003c/em\u003e(6), doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2012RS005049\u003c/span\u003e\u003cspan address=\"10.1029/2012RS005049\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHutchins, M. L., R. H. Holzworth, C. J. Rodger, and J. B. Brundell (2012b), Far-Field Power of Lightning Strokes as Measured by the World Wide Lightning Location Network, Journal of Atmospheric and Oceanic Technology, \u003cem\u003e29\u003c/em\u003e(8), 1102\u0026ndash;1110, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1175/jtech-d-11-00174.1\u003c/span\u003e\u003cspan address=\"10.1175/jtech-d-11-00174.1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJacobson, A. R., R. H. Holzworth, and J. B. Brundell (2021), Using the World Wide Lightning Location Network (WWLLN) to Study Very Low Frequency Transmission in the Earth-Ionosphere Waveguide: 1. Comparison With a Full-Wave Model, \u003cem\u003eRadio Science\u003c/em\u003e, \u003cem\u003e56\u003c/em\u003e(7), e2021RS007293, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2021RS007293\u003c/span\u003e\u003cspan address=\"10.1029/2021RS007293\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKaplan, J. O., and K. H. K. Lau (2021), The WGLC global gridded lightning climatology and time series, Earth Syst. Sci. Data, \u003cem\u003e13\u003c/em\u003e(7), 3219\u0026ndash;3237, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.5194/essd-13-3219-2021\u003c/span\u003e\u003cspan address=\"10.5194/essd-13-3219-2021\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKaplan, J. O., and K. H. K. Lau (2022), World Wide Lightning Location Network (WWLLN) Global Lightning Climatology (WGLC) and time series, 2022 update, Earth Syst. Sci. Data, \u003cem\u003e14\u003c/em\u003e(12), 5665\u0026ndash;5670, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.5194/essd-14-5665-2022\u003c/span\u003e\u003cspan address=\"10.5194/essd-14-5665-2022\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKohlmann, H., W. Schulz, and F. Rachidi (2022), Estimation of Charge Transfer During Long Continuing Currents in Natural Downward Flashes Using Single-Station E-Field Measurements, Journal of Geophysical Research: Atmospheres, \u003cem\u003e127\u003c/em\u003e(6), e2021JD036197, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2021JD036197\u003c/span\u003e\u003cspan address=\"10.1029/2021JD036197\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKolmašov\u0026aacute;, I., et al. (2021), First Observations of Elves and Their Causative Very Strong Lightning Discharges in an Unusual Small-Scale Continental Spring-Time Thunderstorm, Journal of Geophysical Research: Atmospheres, \u003cem\u003e126\u003c/em\u003e(1), e2020JD032825, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2020JD032825\u003c/span\u003e\u003cspan address=\"10.1029/2020JD032825\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKuo, C.-L., T.-Y. Huang, C.-M. Hsu, M. Sato, L.-C. Lee, and N.-H. Lin (2021a), Resolving Elve, Halo and Sprite Halo Images at 10,000 Fps in the Taiwan 2020 Campaign, Atmosphere, \u003cem\u003e12\u003c/em\u003e(8), 1000.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKuo, C.-L., E. Williams, T. Adachi, K. Ihaddadene, S. Celestin, Y. Takahashi, R.-R. Hsu, H. U. Frey, S. B. Mende, and L.-C. Lee (2021b), Experimental Validation of N2 Emission Ratios in Altitude Profiles of Observed Sprites, Frontiers in Earth Science, \u003cem\u003e9\u003c/em\u003e, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3389/feart.2021.687989\u003c/span\u003e\u003cspan address=\"10.3389/feart.2021.687989\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKuo, C. L., et al. (2012), Full-kinetic elve model simulations and their comparisons with the ISUAL observed events, Journal of Geophysical Research: Space Physics, \u003cem\u003e117\u003c/em\u003e(A7), doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2012JA017599\u003c/span\u003e\u003cspan address=\"10.1029/2012JA017599\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLang, T. J., W. A. Lyons, S. A. Cummer, B. R. Fuchs, B. Dolan, S. A. Rutledge, P. Krehbiel, W. Rison, M. Stanley, and T. Ashcraft (2016), Observations of two sprite-producing storms in Colorado, Journal of Geophysical Research: Atmospheres, \u003cem\u003e121\u003c/em\u003e(16), 9675\u0026ndash;9695, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/2016JD025299\u003c/span\u003e\u003cspan address=\"10.1002/2016JD025299\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLang, T. J., W. A. Lyons, S. A. Rutledge, J. D. Meyer, D. R. MacGorman, and S. A. Cummer (2010), Transient luminous events above two mesoscale convective systems: Storm structure and evolution, Journal of Geophysical Research: Space Physics, \u003cem\u003e115\u003c/em\u003e(A5), doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2009JA014500\u003c/span\u003e\u003cspan address=\"10.1029/2009JA014500\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLang, T. J., S. A. Rutledge, and K. C. Wiens (2004), Origins of positive cloud-to-ground lightning flashes in the stratiform region of a mesoscale convective system, Geophysical Research Letters, \u003cem\u003e31\u003c/em\u003e(10), doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2004GL019823\u003c/span\u003e\u003cspan address=\"10.1029/2004GL019823\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLu, G., S. A. Cummer, J. Li, F. Han, R. J. Blakeslee, and H. J. Christian (2009), Charge transfer and in-cloud structure of large-charge-moment positive lightning strokes in a mesoscale convective system, Geophysical Research Letters, \u003cem\u003e36\u003c/em\u003e(15), doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2009GL038880\u003c/span\u003e\u003cspan address=\"10.1029/2009GL038880\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLu, G., B. Yu, S. A. Cummer, K.-M. Peng, A. B. Chen, F. Lyu, X. Xue, F. Liu, R.-R. Hsu, and H.-T. Su (2018), On the Causative Strokes of Halos Observed by ISUAL in the Vicinity of North America, Geophysical Research Letters, \u003cem\u003e45\u003c/em\u003e(19), 10,781\u0026thinsp;\u0026ndash;\u0026thinsp;710,789, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2018GL079594\u003c/span\u003e\u003cspan address=\"10.1029/2018GL079594\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLu, J., et al. (2022), Effects of Convective Mergers on the Evolution of Microphysical and Electrical Activity in a Severe Squall Line Simulated by WRF Coupled With Explicit Electrification Scheme, \u003cem\u003eJournal of Geophysical Research: Atmospheres\u003c/em\u003e, \u003cem\u003e127\u003c/em\u003e(16), e2021JD036398, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2021JD036398\u003c/span\u003e\u003cspan address=\"10.1029/2021JD036398\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLyons, W. A. (2006), The meteorology of transient luminous events-an introduction and overview, Springer Netherlands, Dordrecht.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLyons, W. A., M. Uliasz, and T. E. Nelson (1998), Large Peak Current Cloud-to-Ground Lightning Flashes during the Summer Months in the Contiguous United States, Monthly Weather Review, \u003cem\u003e126\u003c/em\u003e(8), 2217\u0026ndash;2233, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1175/1520-0493(1998)126\u0026lt;2217:LPCCTG\u0026gt;2.0.CO;2\u003c/span\u003e\u003cspan address=\"10.1175/1520-0493(1998)126%3C2217:LPCCTG%3E2.0.CO;2\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMlynarczyk, J., J. B\u0026oacute;r, A. Kulak, M. Popek, and J. Kubisz (2015), An unusual sequence of sprites followed by a secondary TLE: An analysis of ELF radio measurements and optical observations, Journal of Geophysical Research: Space Physics, \u003cem\u003e120\u003c/em\u003e(3), 2241\u0026ndash;2254, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/2014JA020780\u003c/span\u003e\u003cspan address=\"10.1002/2014JA020780\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePan, C., J. Yang, K. Liu, and Y. Wang (2021), Comprehensive Analysis of a Coast Thunderstorm That Produced a Sprite over the Bohai Sea, Atmosphere, \u003cem\u003e12\u003c/em\u003e(6), 718.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eParker, M. D., and R. H. Johnson (2000), Organizational Modes of Midlatitude Mesoscale Convective Systems, Monthly Weather Review, \u003cem\u003e128\u003c/em\u003e(10), 3413\u0026ndash;3436, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1175/1520-0493(2001)129\u0026lt;3413:OMOMMC\u0026gt;2.0.CO;2\u003c/span\u003e\u003cspan address=\"10.1175/1520-0493(2001)129%3C3413:OMOMMC%3E2.0.CO;2\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eParra\u0026ndash;Rojas, F. C., A. Luque, and F. J. Gordillo\u0026ndash;V\u0026aacute;zquez (2013), Chemical and electrical impact of lightning on the Earth mesosphere: The case of sprite halos, Journal of Geophysical Research: Space Physics, \u003cem\u003e118\u003c/em\u003e(8), 5190\u0026ndash;5214, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/jgra.50449\u003c/span\u003e\u003cspan address=\"10.1002/jgra.50449\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eP\u0026eacute;rez-Invern\u0026oacute;n, F. J., A. Luque, and F. J. Gordillo-V\u0026aacute;zquez (2018a), Modeling the Chemical Impact and the Optical Emissions Produced by Lightning-Induced Electromagnetic Fields in the Upper Atmosphere: The case of Halos and Elves Triggered by Different Lightning Discharges, Journal of Geophysical Research: Atmospheres, \u003cem\u003e123\u003c/em\u003e(14), 7615\u0026ndash;7641, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2017JD028235\u003c/span\u003e\u003cspan address=\"10.1029/2017JD028235\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eP\u0026eacute;rez-Invern\u0026oacute;n, F. J., A. Luque, F. J. Gordillo-V\u0026aacute;zquez, M. Sato, T. Ushio, T. Adachi, and A. B. Chen (2018b), Spectroscopic Diagnostic of Halos and Elves Detected From Space-Based Photometers, Journal of Geophysical Research: Atmospheres, \u003cem\u003e123\u003c/em\u003e(22), 12,917\u0026thinsp;\u0026ndash;\u0026thinsp;912,941, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2018JD029053\u003c/span\u003e\u003cspan address=\"10.1029/2018JD029053\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePizzuti, A., J. M. Wilkinson, S. Soula, J. Mlynarczyk, I. Kolmašov\u0026aacute;, O. Santol\u0026iacute;k, R. Scovell, A. Bennett, and M. F\u0026uuml;llekrug (2021), Signatures of large peak current lightning strokes during an unusually intense sprite-producing thunderstorm in southern England, Atmospheric Research, \u003cem\u003e249\u003c/em\u003e, 105357, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.atmosres.2020.105357\u003c/span\u003e\u003cspan address=\"10.1016/j.atmosres.2020.105357\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRodger, C. J., S. Werner, J. B. Brundell, E. H. Lay, N. R. Thomson, R. H. Holzworth, and R. L. Dowden (2006), Detection efficiency of the VLF World-Wide Lightning Location Network (WWLLN): initial case study, Ann. Geophys., \u003cem\u003e24\u003c/em\u003e(12), 3197\u0026ndash;3214, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.5194/angeo-24-3197-2006\u003c/span\u003e\u003cspan address=\"10.5194/angeo-24-3197-2006\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSaba, M. M. F., O. Pinto Jr., and M. G. Ballarotti (2006), Relation between lightning return stroke peak current and following continuing current, Geophysical Research Letters, \u003cem\u003e33\u003c/em\u003e(23), doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2006GL027455\u003c/span\u003e\u003cspan address=\"10.1029/2006GL027455\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSuzuki, T., M. Kamogawa, H. Fujiwara, and S. Hayashi (2022), MCS Stratiform and Convective Regions Associated with Sprites Observed from Mt. Fuji, \u003cem\u003eAtmosphere\u003c/em\u003e, \u003cem\u003e13\u003c/em\u003e(9), 1460.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003evan der Velde, O. A., \u0026Aacute;. Mika, S. Soula, C. Haldoupis, T. Neubert, and U. S. Inan (2006), Observations of the relationship between sprite morphology and in-cloud lightning processes, Journal of Geophysical Research: Atmospheres, \u003cem\u003e111\u003c/em\u003e(D15), doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2005JD006879\u003c/span\u003e\u003cspan address=\"10.1029/2005JD006879\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWestcott, N. E. (1994), Merging of Convective Clouds: Cloud Initiation, Bridging, and Subsequent Growth, \u003cem\u003eMonthly Weather Review\u003c/em\u003e, \u003cem\u003e122\u003c/em\u003e(5), 780\u0026ndash;790, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1175/1520-0493(1994)122\u0026lt;0780:Moccci\u0026gt;2.0.Co;2\u003c/span\u003e\u003cspan address=\"10.1175/1520-0493(1994)122%3C0780:Moccci%3E2.0.Co;2\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWilliams, E., et al. (2012), Resolution of the sprite polarity paradox: The role of halos, \u003cem\u003eRadio Science\u003c/em\u003e, \u003cem\u003e47\u003c/em\u003e, 2002, doi:doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1029/2011RS004794\u003c/span\u003e\u003cspan address=\"10.1029/2011RS004794\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWu, Y. J., et al. (2017), The leading role of atomic oxygen in the collocation of elves and hydroxyl nightglow in the low-latitude mesosphere, Journal of Geophysical Research: Space Physics, \u003cem\u003e122\u003c/em\u003e(5), 5550\u0026ndash;5567, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/2016JA023681\u003c/span\u003e\u003cspan address=\"10.1002/2016JA023681\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eXu, W., E. J. Zipser, C. Liu, and H. Jiang (2010), On the relationships between lightning frequency and thundercloud parameters of regional precipitation systems, Journal of Geophysical Research: Atmospheres, \u003cem\u003e115\u003c/em\u003e(D12), doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2009JD013385\u003c/span\u003e\u003cspan address=\"10.1029/2009JD013385\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYang, J., N. Liu, M. Sato, G. Lu, Y. Wang, and G. Feng (2018), Characteristics of Thunderstorm Structure and Lightning Activity Causing Negative and Positive Sprites, Journal of Geophysical Research: Atmospheres, \u003cem\u003e123\u003c/em\u003e(15), 8190\u0026ndash;8207, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1029/2017JD026759\u003c/span\u003e\u003cspan address=\"10.1029/2017JD026759\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZhu, Y., et al. (2017), Evaluation of ENTLN Performance Characteristics Based on the Ground Truth Natural and Rocket-Triggered Lightning Data Acquired in Florida, Journal of Geophysical Research: Atmospheres, \u003cem\u003e122\u003c/em\u003e(18), 9858\u0026ndash;9866, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1002/2017JD027270\u003c/span\u003e\u003cspan address=\"10.1002/2017JD027270\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZhu, Y., M. Stock, J. Lapierre, and E. DiGangi (2022), Upgrades of the Earth Networks Total Lightning Network in 2021, Remote Sensing, \u003cem\u003e14\u003c/em\u003e(9), 2209.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"terrestrial-atmospheric-and-oceanic-sciences","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"taoj","sideBox":"Learn more about [Terrestrial, Atmospheric and Oceanic Sciences](https://link.springer.com/journal/44195)","snPcode":"44195","submissionUrl":"https://submission.springernature.com/new-submission/44195/3","title":"Terrestrial, Atmospheric and Oceanic Sciences","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Mesoscale Convective System, Transient Luminous Events, Lightning","lastPublishedDoi":"10.21203/rs.3.rs-3910591/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3910591/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eA line of mesoscale convective systems (MCSs) accompanied by hails with strong updraft may produces favorable weather conditions for high flash rates and sprite occurrences. On 18\u0026ndash;20 May, 2018, we observed a total of 287 transient luminous events (TLEs) in the Taiwan campaign. After analyzing flashes from Earth Networks Total Lightning Network (ENTLN), the observation region has a maximum CG flash rate 115.1 min-1 (95.1 min-1 for \u0026ndash;CGs and 20.0 min-1 for +\u0026thinsp;CG) within a single cell of MCSs on May 20 within a radius 55 km. We investigated the TLEs activity associated with the multi-cells in the MCS, and found that sudden increases of TLEs are associated with the merging stage of new and old cells and the dissipating stage of cell. The flashes associated with TLEs with halo emissions have a tendency of large peak current. The TLEs with their parent flashes and extremely high peak currents (200, 244, 261, 267, 311, 357 kA) were shown, and most of events have common optical features of sprite halos and clusters of sprites structures.\u003c/p\u003e","manuscriptTitle":"Case study on sprite and lightning activities associated with the cell life cycle in a mesoscale convective system","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-02-28 18:56:15","doi":"10.21203/rs.3.rs-3910591/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2024-06-24T23:37:32+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2024-03-11T12:12:38+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-02-22T17:12:57+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-01-29T09:24:32+00:00","index":"","fulltext":""},{"type":"submitted","content":"Terrestrial, Atmospheric and Oceanic Sciences","date":"2024-01-28T22:50:11+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"terrestrial-atmospheric-and-oceanic-sciences","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"taoj","sideBox":"Learn more about [Terrestrial, Atmospheric and Oceanic Sciences](https://link.springer.com/journal/44195)","snPcode":"44195","submissionUrl":"https://submission.springernature.com/new-submission/44195/3","title":"Terrestrial, Atmospheric and Oceanic Sciences","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"92534353-605a-445e-af8d-f242ade27a5c","owner":[],"postedDate":"February 28th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2024-02-28T18:56:15+00:00","versionOfRecord":[],"versionCreatedAt":"2024-02-28 18:56:15","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3910591","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3910591","identity":"rs-3910591","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}