2017-08-28, 15:13
Richo,
I used the very beginning of the signal, so this cannot be a reflection which is contributing only later to the signal. The line of sight from the station to the stroke was only over the sea, so the ground wave had little attenuation. I will try to get the opinion of lightning location specialists on this topic (identification of polarity for distant strokes).
Cutty, there was another stroke only 40 msec later at the same postition, so this is consistent with a negative stroke. Positive CG has only very rarely a second stroke at exactly the same position. A problem with +CG is that these waveforms are more complicated than -CG because very often there is significant cloud discharges before the return stroke. Sometimes this even leads to strong +CG not being identified correctly, instead a cloud discharge is assumed by the system.
What do the colors in your attachments stand for?
I used the very beginning of the signal, so this cannot be a reflection which is contributing only later to the signal. The line of sight from the station to the stroke was only over the sea, so the ground wave had little attenuation. I will try to get the opinion of lightning location specialists on this topic (identification of polarity for distant strokes).
Cutty, there was another stroke only 40 msec later at the same postition, so this is consistent with a negative stroke. Positive CG has only very rarely a second stroke at exactly the same position. A problem with +CG is that these waveforms are more complicated than -CG because very often there is significant cloud discharges before the return stroke. Sometimes this even leads to strong +CG not being identified correctly, instead a cloud discharge is assumed by the system.
What do the colors in your attachments stand for?
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