Comparison of peak currents estimated by lightning location system and ground truth references obtained in Morro do Cachimbo station

The peak currents of seven first and ten subsequent strokes measured at the instrumented tower of Morro do Cachimbo Station and estimated by the Brazilian lightning location system were compared. The evaluation shows a trend of the LLS to underestimate the amplitudes of currents. The mean ratio between the measured and the estimated peak currents exceeds 1.4 for first strokes and 1.7 for subsequent strokes. It was verified that this ratio could be significantly decreased using parameters capable of properly representing the attenuation of the propagated lightning electromagnetic signal.

► Measured peak currents were compared to those estimated by lightning location system.
► Lightning location system underestimates the peak currents.
► The mean ratio of the measured and estimated peak currents exceeds 1.4 for first strokes and 1.7 for subsequent strokes.
► Improved representation of the attenuation of the lightning electromagnetic field propagation decreases this ratio.