The Lightning Distribution of Tropical Cyclones over the Western North Pacific

Abstract

This study examines the characteristics of tropical cyclone (TC) lightning distribution and its relationship with TC intensity and environmental vertical wind shear (VWS) over the western North Pacific. It uses data from the World Wide Lightning Location Network and operational global analysis data from National Centers for Environmental Prediction Final Analysis for 230 TCs during 2005–2017. The spatial distribution of TC lightning frequency and normalized lightning rate demonstrates that the VWS dominates the azimuthal distribution of the lightning. The flashes are active in the downshear-left side of the inner core and the downshear-right side of the outer region. TC lightning distribution for various VWS strengths and TC intensities are further investigated. As VWS increases, the flashes of lightning become more asymmetric and exhibit a higher proportion at the outer region of the downshear side. Moreover, the same features occur as TC intensity decreases. A series of composite analyses indicated that stronger TCs with weaker VWS exhibit a more compact and symmetric lightning distribution, whereas weaker TCs with stronger VWS have a more asymmetric lightning distribution. Furthermore, the TC lightning distribution and its association with TC intensity changes are also examined for three lead times. Results show that among the composite analyses of five TC intensity changes, the lightning distribution for rapid intensification type exhibits more inner-core lightning and more axisymmetric than the distributions for other categories. These features result from favorable environmental conditions comprising greater upper level divergence, sea surface temperature, maximum potential intensity, and weaker vertical wind shear.

WWLLN Hot and Cold-Spots of Lightning Activity and Their Relation to Climate in an Extended Central America Region 2012–2020

“…WWLLN reports that "recent research indicates our detection efficiency for strokes about 30 kA is approximately 30% globally". More recently, [59] stressed the fact that in the early stages of the network (before 2008), the detection efficiency was low because there were only a relatively small number of sensors. Lightning efficiency has been monotonically increasing since the early days of the network [58], by a factor of about 1.25 (60 in 2012, [58]; to over 70 in recent years, http://wwlln.net/ accessed on 28 Decmber 2021).…”

“…Lightning efficiency has been monotonically increasing since the early days of the network [58], by a factor of about 1.25 (60 in 2012, [58]; to over 70 in recent years, http://wwlln.net/ accessed on 28 Decmber 2021). Studies have also used some sort of adjustment factors for WWLLN D based on the LIS/OTD (Lightning Imaging Sensor, LIS, and Optical Transient Detector, OTD) climatology [59], although LIS/OTD has a quite different detector sensor detecting pulses of illumination (produced by lightning) above background levels. Estimates of precipitation have been possible due to satellite monitoring programs such as the Tropical Rainfall Measuring Mission (TRMM, https://gpm.nasa.gov/missions/ trmm, accessed on 28 December 2021), the Global Precipitation Measurement (GPM) mission https://gpm.nasa.gov/missions/GPM, accessed on 28 December 2021), and CHIRPS (https://www.chc.ucsb.edu/data/chirps, accessed on 28 December 2021), a project using rain gauge and satellite observations.…”

“…As reported by [55], "though no single lightning climatology can be said to be definitive, the WWLLN lightning climatology appears to be consistent with in situ rainfall observations and with the TRMM rainfall climatology". Following [59] when discussing TRMM satellite studies, we considered that by estimating monthly or annual lightning averages for the period 2012-2020, the gross statistical characteristics of the lightning-precipitation patterns will emerge.…”

Transport of Water Vapor from Tropical Cyclones to the Upper Troposphere

“…Price et al [13] found that in the majority of tropical cyclones, lightning frequency and maximum sustained winds are significantly correlated (mean correlation coefficient of 0.82); however, the maximum sustained winds and minimum pressures in hurricanes are preceded by increases in lightning activity approximately one day before the peak winds. Numerous other recent studies have also investigated the link between lightning and tropical cyclones [14][15][16][17]. In this study, we expand on these previous studies to investigate the role of tropical cyclones on the transport of water vapor into the upper troposphere.…”

Climatologia do Índice do Potencial de Gênese de Ciclones Tropicais nos Oceanos Adjacentes à América do Sul

“…O V shear pode ser calculado de duas maneiras: (i) considerando a diferença da intensidade do vento entre dois níveis de pressão e, (ii) considerando a diferença vetorial como mostrado na Equação 4. Essa última é chamada, no inglês, de Environmental Vertical Wind Shear (Lin & Chou, 2020). No cálculo do IPG é usada a maneira (ii), mas para a rápida visualização e compreensão dos resultados, a maneira (i) é mais apropriada, pois quando o cisalhamento mostra valores positivos (negativos) indica que os ventos em altos níveis são mais intensos (fracos) do que em baixos níveis da atmosfera.…”