A lightning flash, named 0503 in which the wire was not connected directly to the lightning rod but via a 5m length of nylon thread, has been triggered during SHATLE (Shandong Artificially Triggering Lightning Experiment, SHATLE). Synchronous data of the current, and close electric and magnetic fields have been obtained. The results show that the discharge processes of the initial stage (IS) in this triggered flash were different from the usual classical artificially-triggered lightning flash 0602 (the wire is connected with the rod directly) and altitude-triggered lightning. A large pulse with a current of 720A resulted from the breakdown of the 5m air gap occurred first during flash 0503, and the corresponding electric field at 60m from the rod was 0.38kV/m. The upward positive leader (UPL) propagated continuously after the large pulse. The geometric mean (GM) of the UPL peak current was 23.0A. The vaporization of the wire occurred during the initial continuous current (ICC) stage and the largest current pulse was about 400A. Comparing with triggered flash 0503, the discharge processes of IS in flash 0602 were simple, only two large pulses similar to each other, occurred before dart leader/return stroke sequences. The peak current of the first pulse was 2.1kA and its corresponding electric and magnetic fields at 60m from the lightning channel were 0.98 kV/m and 7.03μT, respectively. During the second pulse, the wire disintegrated. The current decreased to the background at the moment of the wire disintegration. The current of the second pulse in triggered flash 0602 was 2.8kA, and the corresponding electric and magnetic fields at 60m were 1.22kV/m and 9.01μT, respectively.
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