Lightning Discharge Studies in a Tropical Area

I. Cloud-to-ground Discharges

Abstract

A simultaneous recording of electrostatic (e.s.) field, low frequency (l.f.) field change, optical, 1MHz and 14MHz radiations from ground flashes in a tropical area was made on a multichannel magnetic tape recorder. The pre-predischarge radiation was identified at high frequencies without corresponding optical, e.s, or l.f. changes. No sudden field change was observed at the beginning of the B process and, in general, the e.s. field change during the leader process could not be divided into the B, I and L stages; but the 1MHz and 14MHz radiation components could be divided in this way in many cases. The charges brought down by tropical ground flashes were found to be of the same order of magnitude as in other areas. The charge height of the cell leading to the first stroke was estimated at 6km.