Relative detection efficiency of the World Wide Lightning Location Network

Using the detected energy per strokes of the World Wide Lightning Location Network (WWLLN) we calculate the relative detection efficiency for the network as if it had a uniform detection efficiency. The model uses the energy statistics of located strokes to determine which stations are sensitive to what stroke energies. We are then able to estimate the number of strokes that may be missing from any given regions as compared to the best, most sensitive regions of the WWLLN network. Stroke density maps can be corrected with the knowledge of how sensitive various regions of the network are operating. This new model for the relative WWLLN detection efficiency compensates for the uneven global coverage of the network sensors as well as variations in very low frequency (VLF) propagation. The model gives a way to represent the global distribution of strokes as if observed by a globally uniform network. The model results are analyzed in spatial and temporal regimes, and the effects of a single VLF detector going offline are investigated in areas of sparse and dense detector coverage. The results are also used to show spatial, temporal and energy distributions as seen by the detection efficiency corrected WWLLN. Citation: Hutchins, M. L., R. H. Holzworth, J. B. Brundell, and C. J. Rodger (2012), Relative detection efficiency of the World Wide Lightning Location Network, Radio Sci., 47, RS6005, doi:10.1029/2012RS005049.