2014 International Conference on Lightning Protection ( ICLP ) , Shanghai , China Characteristics of Downward Lightning Return Strokes Occurring on Tall Structures with Different Heights

Observations for 58 natural downward negative lightning flashes with confirmed grounding points were analyzed in this paper to study the difference between the characteristics of negative lightning return strokes occurring on tall structures with different heights. The results show that the averaged difference of the number of strokes per flash and the inter-stroke intervals between the flashes occurring on structures taller than 200 m and those lower than 200 m is not obvious. But the peak currents, the 10-90% rise times and the widths from the 10% wave front to the 50% waveform tail of the optical pulses, induced by the lightning strokes occurring on structures taller than 200 m is much larger than those lower than 200 m. Futhermore, the difference between structures with different heights seem to be more significant for the first strokes rather than the subsequent strokes. .Keywordsdownward lightning flash; tall structure; characteristics of return stroke; luminosity pulse