WWLL global lightning detection system: Regional validation study in Brazil

Abstract

[1] An experimental lightning detection network, the World Wide Lightning Location network (WWLL), is being developed to provide real time global coverage with 10 km location accuracy and at least 50% detection efficiency. This paper provides a ''worst case'' analysis of WWLL location accuracy in Brazil where the VLF lightning receivers that make up the network are very distant (>7000 km). Through comparison to a local lightning detection network, we analyze the detection accuracy in Brazil with respect to time, location, and peak current of lightning strokes. In this study, we find that WWLL detection is highly dependent upon the peak return stroke current, resulting in detection of about 0.3% of the total lightning strokes. However, the detected strokes have a location accuracy of 20.25 ± 13.5 km and a temporal accuracy of 0.06 ± 0.2 ms, providing a good overview of regions of overall global lightning activity in real time.

A performance assessment of the World Wide Lightning Location Network (WWLLN) via comparison with the Canadian Lightning Detection Network (CLDN)

“…The handling practice for the WWLLN data used in this paper ensures that the time residual for the data collected (indicating the quality of the fit to the data) is less than 30 µs and that the lightning strokes are detected by at least five WWLLN VLF receiver stations (Rodger et al, 2009). This protocol differs from some previous studies that were performed early in the establishment of the network (Lay et al, 2004;Rodger et al, 2005), as comparisons to regional networks led to improvements in WWLLN data handling practices (Dr. Craig Rodger, personal communication, August 2009).…”

“…The WWLLN is a real-time, world-wide, ground-based network operated by the University of Washington that can detect strong lightning strokes occurring anywhere in the world (Dowden et al, 2002;Lay et al, 2004;Jacobson et al, 2006;Rodger et al, 2005Rodger et al, , 2006Rodger et al, , 2009. The network was initiated with the intention of achieving global detection with a location accuracy of less than 10 km (Rodger et al, 2009).…”

“…The sensors are located on ferro-concrete buildings around the world because at VLF, they act as conductors and stay at ground potential, hence shielding the antenna from local man-made noise (Dowden et al, 2002). Moreover, in the receiver bandwidth, the vertical electric field from strong lightning dominates over power line noise, therefore, the locations of these receivers do not necessarily have to be in noise-free conditions (Lay et al, 2004).…”

The version 3 OMI NO<sub>2</sub> standard product

“…Recent research has shown that satellite measurements are a useful tool for estimating LNO x (Boersma et al, 2005;Beirle et al, 2010;Bucsela et al, 2010;Pickering et al, 2016). Pickering et al (2016) combined OMI V trop data with data from the World Wide Lightning Location Network (WWLLN) (Dowden et al, 2002;Lay et al, 2004;Virts et al, 2013) to estimate the production efficiency (PE) of LNO x (moles per flash). Using SPv2 and WWLLN data from the Gulf of Mexico over five Northern Hemisphere summers (2007)(2008)(2009)(2010)(2011), they obtained a mean PE value of 80 ± 45 mol flash −1 .…”

Development of a hybrid variational-ensemble data assimilation technique for observed lightning tested in a mesoscale model

“…The WWLLN is an experimental lightning detection network that provides the location of cloud-to-ground (CG) and some intra-cloud lightning (IC) strikes in real time. It has a global coverage with 10 km location accuracy and flash detection accuracy greater than 50 % (Lay et al, 2004). WWLLN is for the most part a time average of geo-located CG lightning flashes that cannot address the cloud-resolving characteristics of lightning.…”