A Clustering Poisson model for characterizing the interarrival times of sferics

Abstract

[1] The noise waveform of atmospheric radio noise below 100 MHz is typically impulsive in nature. The impulses are caused by atmospheric events, mainly lightning strokes, that create electromagnetic emissions known as sferics. Sferic impulses in the noise waveform are seen to cluster in groups, indicating an underlying clustering process related to the physical characteristics of the lightning mechanism. The objective of this work is the statistical modeling of the clustering of noise impulses in atmospheric radio noise in the range 10 Hz to 60 kHz (denoted low-frequency noise). Based on hundreds of hours of impulse interarrival time measurements made by the Stanford Radio Noise Survey System on such noise, a new Clustering Poisson atmospheric noise model is developed to describe the clustering process. This new statistical model is based on several previously known statistical-physical models of atmospheric radio noise, but in addition to these models it takes into account the clustering of sferic impulses. It is shown that the clustering model accurately characterizes the impulse interarrival time distributions found in low-frequency radio noise data.

The Earth's electromagnetic environment

“…This transient nature is often characterized by a sudden rise and a slow decay which is, for example, apparent in geomagnetic storms and lightning discharges [ Füllekrug , 2006]. The second characteristic is the relationship between the recurrence time and the intensity of an event, e.g., strong events are usually more rare and weak events usually occur more often [e.g., Chrissan and Fraser ‐ Smith , 2003]. Whether these recurring transient events are sufficient to explain the observed scaling law remains to be explored in future studies.…”

Sprites in low‐frequency radio noise

“…In this picture, the quick succession of consecutive lightning pulses from radiating stepped leaders might blend into the slowly varying background radiation observed here, possibly assisted by wave propagation effects. However, to the best of our knowledge, there is currently no scientific rationale to describe the transition from Poisson‐distributed lightning return stroke intensities [ Chrissan and Fraser‐Smith , ] or stepped leaders to smoothly varying low frequency background radiation. On the other hand, the mere absence of such kind of theory does not exclude the possibility of this blending process to occur.…”

A Global Survey of ELF/VLF Radio Noise

“…The APD results presented in this dissertation are particularly important in communications and we expanded upon them in a paper that was published in 2002 [Chrissan and FraserSmith, 2000]. The principal theoretical result of the dissertation, a clustering Poisson model for characterizing the interarrival times of ELF/VLF sferics, has now been described in a paper that will shortly be published [Chrissan and Fraser-Smith, 2002].…”

“…Our most recent work specifically describes improvements to low-frequency radio communications that should result from our analyses and modeling [Chrissan, 1998;Chrissan and Fraser-Smith, 2000;Chrissan and Fraser-Smith, 2002] and it provides what is undoubtedly the most comprehensive description of the operationally-important APD statistics for ELF/VLF noise as well as a detailed model of the clustering that occurs in ELF/VLF sferic occurrences.…”