Evaluation of the performance of the World Wide Lightning Location Network (WWLLN) using the lightning detection network (LINET) as a truth

Abstract

Observations from lightning detection networks are useful for forecasting or monitoring several phenomena or parameters such as bushfires or nitrogen oxide production. As networks are constantly expanding and their detection capabilities are improving, it is essential to understand their performance. A systematic evaluation of the performance of the World Wide Lightning Location Network (WWLLN) in northern Benin is carried out using data from the lightning detection network (LINET) data as ground truth. The study runs from 18 June to 18 November 2006. The detection efficiency of the WWLLN is found to be strongly dependent on the peak current. It is low and reveals the distance of the sensors from the area. This same sensitivity to peak current explains the bias between the spatial and temporal localisation of the two networks. The peak of the period, in terms of the number of events observed, is obtained in July for the LINET and in September for the WWLLN. The diurnal variation indicates an overall peak of activity in the evening for both networks but with a slight time lag for WWLLN. However, taking into account the flashes with peak current greater than or equal to 30 kA, it is noted that the two networks are almost identically located. The results also show that the WWLLN is capable of locating both cloud-to-ground (CG) and inter-cloud (IC) lightning. Additional receiving stations are continuously added to the network, which improves detection efficiency.