Certain intracloud lightning discharges emit energetic, multi-microsecondpulsetrains of radio noise. Observations of this distinctive form oflightning date from 1980 and have involved both ground-based andsatellite-based radio recording systems. The underlying intracloud lightningdischarges have been referred to as "Narrow Bipolar Pulses", "NarrowBipolar Events", and "Compact Intracloud Discharges". An importantdiscriminant for this species of radio emission is that, in the range above~30 MHz, it consists of several microseconds of intense radio noise.When the intracloud emission is viewed from a satellite, each radiopulsetrain is received both from a direct lightning-to-satellite path, andafter some delay, from a path via ground. Thus one recording of the radioemission, if of sufficient length, contains the "view" of the intracloudemission from two different angles. One view is of radiation exiting theemitter into the upper hemisphere, the other for radiation exiting into thelower hemisphere. However, the propagation conditions are similar, exceptthat one path includes a ground reflection, while the other does not.One would normally expect a stereoscopic double view of the "same"emission process to provide two almost congruent time series, one delayedfrom the other, and also differing due to the different propagation effectsalong the two signal paths, namely, the ground reflection. We presentsomewhat unexpected results on this matter, using recordings from the FORTEsatellite at a passband 118–141 MHz, with simultaneous data at 26–49 MHz. Wefind that the 118–141 MHz pulsetrain's detailed time-dependence iscompletely uncorrelated between the two views of the process. We examinestatistics of the 118–141 MHz pulsetrain's integrated power and show thatthe power emitted into the lower hemisphere, on average, exceeds the poweremitted into the upper hemisphere. Finally, we examine statistical measuresof the amplitude distribution and show that the 118–141 MHz signal emitteddownward is slightly more dominated by discrete, temporally-narrow impulsesthan is the signal emitted upward.
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