Atmospheric Measurement Techniques www.atmos-meas-tech.net 1867-1381 1867-8548 3 4 2010 10.5194/amt-3-1143-2010 http://www.atmos-meas-tech.net/3/1143/2010/ http://www.atmos-meas-tech.net/3/1143/2010/amt-3-1143-2010.html http://www.atmos-meas-tech.net/3/1143/2010/amt-3-1143-2010.pdf 1143 1153 2010-08-27 A performance assessment of the World Wide Lightning Location Network (WWLLN) via comparison with the Canadian Lightning Detection Network (CLDN) D. Abreu D. Chandan R. H. Holzworth K. Strong strong@atmosp.physics.utoronto.ca Department of Physics, University of Toronto, Ontario, Canada Departments of Earth and Space Sciences, and Physics, University of Washington, Washington, USA The World Wide Lightning Location Network (WWLLN) uses globally-distributed Very Low Frequency (VLF) receivers in order to observe lightning around the globe. Its objective is to locate as many global lightning strokes as possible, with high temporal and spatial (< 10 km) accuracy. Since detection is done in the VLF range, signals from high peak current lightning strokes are able to propagate up to ~104 km before being detected by the WWLLN sensors, allowing for receiving stations to be sparsely spaced. Through a comparison with measurements made by the Canadian Lightning Detection Network (CLDN) between May and August 2008 over a 4° latitude by 4° longitude region centered on Toronto, Canada, this study found that WWLLN detection was most sensitive to high peak current lightning strokes. Events were considered shared between the two networks if they fell within 0.5 ms of each other. Using this criterion, 19 128 WWLLN strokes (analyzed using the Stroke_B algorithm) were shared with CLDN lightning strokes, producing a detection efficiency of 2.8%. The peak current threshold for WWLLN detection is found to be ~20 kA, with its detection efficiency increasing from 11.3% for peak currents greater than 20 kA to 75.8% for peak currents greater than 120 kA. 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