Initial-stage pulses in upward lightning: Leader/return stroke versus M-component mode of charge transfer to ground
2008 (English)In: Geophysical Research Letters, ISSN 0094-8276, Vol. 35, no 13, L13812- p.Article in journal (Refereed) Published
We analyzed high-speed video images and corresponding current records for eight upward lightning flashes initiated by the Peissenberg tower (160 m) in Germany. These flashes contained a total of 33 measurable initial stage (IS) current pulses, which are superimposed on steady IS currents. Seven IS pulses had relatively short (< 8 mu s) 10-to-90% risetimes and 26 IS pulses had relatively long (> 8 mu s) risetimes. Six (86%) of seven IS current pulses with shorter risetimes each developed in a newly-illuminated branch, and 25 (96%) of 26 IS pulses with longer risetimes occurred in already luminous (current-carrying) channels. These results support the hypothesis that longer risetimes are indicative of the M-component mode of charge transfer to ground, while shorter risetimes are associated with the leader/return stroke mode. Similar results were obtained for M-component pulses that are superimposed on continuing currents following return-stroke pulses.
Place, publisher, year, edition, pages
2008. Vol. 35, no 13, L13812- p.
Earth and Related Environmental Sciences Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-62544DOI: 10.1029/2008GL034148ISI: 000257738600004OAI: oai:DiVA.org:kth-62544DiVA: diva2:480926
QC 201201202012-01-202012-01-192012-01-20Bibliographically approved