oa About the Intensity of Strokes in Negative Lightning Flashes

Negative cloud-to-ground lightning flashes were recorded by a lightning positioning and tracking system (LPATS) in the region of the Mount Agulhas Negras (altitude of 2787 m) in Brazil, during the winter and summer season of 1993. The dependence of the stroke peakcurrent on the order of the stroke, the flash multiplicity and the season was investigated. It was found that subsequent strokes tend to be less intense than first-order strokes and that first-order strokes tend to be more intense in multiple stroke flashes. It seems that the larger is the multiplicity, the higher is the intensity of the first-order stroke. The above results are more evident during the winter season. It was also found that the geometric mean of the first-order stroke peak-current increases in the winter season. The dependence of the results on the high altitude of the observation site was also investigated. Apparently, the high altitude of Mount Agulhas Negras has an effect on the lightning intensity during the summer season.