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Summary Lightning strikes kill hundreds of millions of trees annually, but their role in shaping tree life history and diversity is largely unknown.Here, we use data from a unique lightning location system to show that some individual trees counterintuitively benefit from being struck by lightning.Lightning killed 56% of 93 directly struck trees and caused an average of 41% crown dieback among the survivors. However, among these struck trees, 10 direct strikes caused negligible damage toDipteryx oleiferatrees while killing 78% of their lianas and 2.1 Mg of competitor tree biomass. Nine trees of other long‐lived taxa survived lightning with similar benefits. On average, aD. oleiferatree > 60 cm in diameter is struck by lightning at least five times during its lifetime, conferring these benefits repeatedly. We estimate that the ability to survive lightning increases lifetime fecundity 14‐fold, largely because of reduced competition from lianas and neighboring trees. Moreover, the unusual heights and wide crowns ofD. oleiferaincrease the probability of a direct strike by 49–68% relative to trees of the same diameter with average allometries.These patterns suggest that lightning plays an underappreciated role in tree competition, life history strategies, and species coexistence. 

Urbanization tends to increase local lightning frequency (i.e. the ‘lightning enhancement’ effect). Despite many urban areas showing lightning enhancement, the prevalence of these effects is unknown and the drivers underlying these patterns are poorly quantified. We conducted a global assessment of cloud-to-ground lightning flashes (lightning strikes) across 349 cities to evaluate how the likelihood and magnitude of lightning enhancement vary with geography, climate, air pollution, topography and urban development. The likelihood of exhibiting lightning enhancement increased with higher temperature and precipitation in urban areas relative to their natural surroundings (i.e. urban heat islands and elevated urban precipitation), higher regional lightning strike frequency, greater distance to water bodies and lower elevations. Lightning enhancement was stronger in cities with conspicuous heat islands and elevated urban precipitation effects, higher lightning strike frequency, larger urban areas and lower latitudes. The particularly strong effects of elevated urban temperature and precipitation indicate that these are dominant mechanisms by which cities cause local lightning enhancement. 

Abstract During November 2018–April 2019, an 11-station very high frequency (VHF) Lightning Mapping Array (LMA) was deployed to Córdoba Province, Argentina. The purpose of the LMA was validation of the Geostationary Lightning Mapper (GLM), but the deployment was coordinated with two field campaigns. The LMA observed 2.9 million flashes (≥ five sources) during 163 days, and level-1 (VHF locations), level-2 (flashes classified), and level-3 (gridded products) datasets have been made public. The network’s performance allows scientifically useful analysis within 100 km when at least seven stations were active. Careful analysis beyond 100 km is also possible. The LMA dataset includes many examples of intense storms with extremely high flash rates (>1 s−1), electrical discharges in overshooting tops (OTs), as well as anomalously charged thunderstorms with low-altitude lightning. The modal flash altitude was 10 km, but many flashes occurred at very high altitude (15–20 km). There were also anomalous and stratiform flashes near 5–7 km in altitude. Most flashes were small (<50 km2 area). Comparisons with GLM on 14 and 20 December 2018 indicated that GLM most successfully detected larger flashes (i.e., more than 100 VHF sources), with detection efficiency (DE) up to 90%. However, GLM DE was reduced for flashes that were smaller or that occurred lower in the cloud (e.g., near 6-km altitude). GLM DE also was reduced during a period of OT electrical discharges. Overall, GLM DE was a strong function of thunderstorm evolution and the dominant characteristics of the lightning it produced. 

Summary Lightning is an important agent of plant mortality and disturbance in forests. Lightning‐caused disturbance is highly variable in terms of its area of effect and disturbance severity (i.e. tree damage and death), but we do not know how this variation is influenced by forest structure and plant composition.We used a novel lightning detection system to quantify how lianas influenced the severity and spatial extent (i.e. area) of lightning disturbance using 78 lightning strikes in central Panama.The local density of lianas (measured as liana basal area) was positively associated with the number of trees killed and damaged by lightning, and patterns of plant damage indicated that this occurred because lianas facilitated more electrical connections from large to small trees. Liana presence, however, did not increase the area of the disturbance. Thus, lianas increased the severity of lightning disturbance by facilitating damage to additional trees without influencing the footprint of the disturbance.These findings indicate that lianas spread electricity to damage and kill understory trees that otherwise would survive a strike. As liana abundance increases in tropical forests, their negative effects on tree survival with respect to the severity of lightning‐related tree damage and death are likely to increase. 

Abstract In this study we explored the environmental conditions hypothesized to induce a dominant charge structure in thunderstorms in the province of Cordoba, Argentina, during the RELAMPAGO‐CACTI (Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations‐Clouds, Aerosols, Complex Terrain Interactions) field campaigns. Hypothesized environmental conditions are thought to be related to small warm cloud residence time and warm rain growth suppression, which lead to high cloud liquid water contents in the mixed‐phase zone, contributing to positive charging of graupel and anomalous charge structure storms. Data from radiosondes, a cloud condensation nuclei (CCN) ground‐based instrument and reanalysis were used to characterize the proximity inflow air of storms with anomalous and normal charge structures. Consistent with the initial hypothesis, anomalous storms had small warm cloud depth caused by dry low‐level humidity and low 0°C height. Anomalous storms were associated with lower CCN concentrations than normal storms, an opposite result to the initial expectation. High CAPE is not an important condition for the development of anomalous storms in Argentina, as no clear pattern could be found among the different parameters calculated for updraft proxy that would be consistent with the initial hypothesis. 

Abstract Lightning is a common source of disturbance, but its ecological effects in tropical forests are largely undescribed. Here we quantify the contributions of lightning strikes to forest turnover and plant mortality in a lowland Panamanian forest using a real‐time lightning monitoring system. We examined 2,195 lightning‐damaged trees distributed among 93 different strikes. None exhibited scars or fires. On average, each strike disturbed 451 m²(95% CI: 365–545 m²), created a canopy gap of 304 m²(95% CI 198–454 m²), and caused 7.36 Mg of woody biomass turnover (CI: 5.36–9.65 Mg). Cumulatively, we estimate that lightning strikes in this forest create canopy gaps equaling 0.39% of forest canopy area, representing 20.1% of annual gap area formation, and are responsible for 16.1% of total woody biomass turnover. Trees, lianas, herbaceous climbers and epiphytes were killed by lightning at rates 8–29 times greater than their baseline mortality rates in undamaged control sites. The likelihood of lightning‐caused death was higher for trees, lianas, and herbaceous climbers than for epiphytes, and high liana mortality suggests that lightning is an important driver of liana turnover. These results indicate that lightning influences gap dynamics, plant community composition and carbon storage capacity in some tropical forests. 

Abstract A new automated method to retrieve charge layer polarity from flashes, named Chargepol, is presented in this paper. Using data from the NASA Lightning Mapping Array (LMA) deployed during the Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations (RELAMPAGO) field campaign in Cordoba, Argentina, from November 2018 to April 2019, this method estimates the polarity of vertical charge distributions and their altitudes and thicknesses (or vertical depth) using the very‐high frequency (VHF) source emissions detected by LMAs. When this method is applied to LMA data for extended periods of time, it is capable of inferring a storm's bulk electrical charge structure throughout its life cycle. This method reliably predicted the polarity of charge within which lightning flashes propagated and was validated in comparison to methods that require manual assignment of polarities via visual inspection of VHF lightning sources. Examples of normal and anomalous charge structures retrieved using Chargepol for storms in Central Argentina during RELAMPAGO are presented for the first time. Application of Chargepol to five months of LMA data in Central Argentina and several locations in the United States allowed for the characterization of the charge structure in these regions and for a reliable comparison using the same methodology. About 13.3% of Cordoba thunderstorms were defined by an anomalous charge structure, slightly higher than in Oklahoma (12.5%) and West Texas (11.1%), higher than Alabama (7.3%), and considerably lower than in Colorado (82.6%). Some of the Cordoba anomalous thunderstorms presented enhanced low‐level positive charge, a feature rarely if ever observed in Colorado thunderstorms.