Far-Field Power of Lightning Strokes as Measured by the World Wide Lightning Location Network

Abstract

The World Wide Lightning Location Network (WWLLN) is a long-range network capable of locating lightning strokes in space and time. While able to locate lightning to within a few kilometers and tens of microseconds, the network currently does not measure any characteristics of the strokes themselves. The capabilities of the network are expanded to allow for measurements of the far-field power from the root-mean-square electric field of the detected strokes in the 6–18-kHz band. This is accomplished by calibrating the network from a single well-calibrated station using a bootstrapping method. With this technique the global median stroke power seen by the network is 1.0 × 106 W, with an average uncertainty of 17%. The results are validated through comparison to the return-stroke peak current as measured by the New Zealand Lightning Detection Network and to the previous ground wave power measurements in the literature. The global median stroke power herein is found to be four orders of magnitude lower than that reported earlier for the measurements, including the nearby ground and sky wave. However, it is found that the far-field waveguide mode observations herein are consistent with the previous literature because of differences in observational techniques and the efficiency of coupling into a propagation wave in the Earth–ionosphere waveguide. This study demonstrates that the WWLLN-determined powers can be used to estimate the return-stroke peak currents of individual lightning strokes occurring throughout the globe.

Ionospheric effects of earthquakes in Japan in March 2011 obtained from observations of lightning electromagnetic radio signals

“…The analysis reveals that the change in the exponential dependence is connected with the transition from the amplitudes of negative discharges to those of positive discharges, which are known to have higher values of currents running in the lightning channel. The data of the WWLLN network, obtained by the method of Hutchins et al (2012), are used to estimate the signal amplitudes in thunderstorm centers. Thus, in search of the EQ effects and their precursors in the amplitude variations of atmospherics, it was necessary to choose the signals with an amplitude lower than the transition area, but close to it.…”

Natural Field Electromagnetics Using a Partially Known Source: Improvements to Signal to Noise Ratios

“…The WWLLN measures the time of group arrival of a sferic relative to GPS time and triangulates a source location using a network of over 50 sensors (Dowden et al, 2002). Hutchins et al (2012) reported WWLLN timing errors to be within 10 microseconds and location accuracies in the order of the wavelength of the radiation (10-15 km). Abarca et al (2010) reported WWLLN detection efficiencies of 30 to 50% for cloud-to-ground strokes (CG) and intra-cloud strokes (IC) above 40 kA, and 10 to 15% for all global CG strokes.…”

“…Abarca et al (2010) reported WWLLN detection efficiencies of 30 to 50% for cloud-to-ground strokes (CG) and intra-cloud strokes (IC) above 40 kA, and 10 to 15% for all global CG strokes. The WWLLN also provide lightning stroke power estimates integrated over a 1 ms waveform (Hutchins et al, 2012).…”

Preliminary Study on Features of Lightning Discharge around Japan Using World Wide Lightning Location Network Data

“…The sferic attenuation along the path was calculated based on the ionospheric model with regard to the influence of its diurnal variation. In comparison with ground-based lightning data detected by IMPACT-ESP2 sensors over New Zealand, the coefficient of determination (R 2 ) for the estimated peak currents between the two sensors was 0.92 (Hutchins et al 2012a).…”