Interlinked Spatiotemporal Patterns of Magnetospheric Lower-Band Whistler Mode Waves

Natural electromagnetic wave emissions of lower-band chorus and exohiss affect energetic electron populations in the Earth's outer radiation belt. Despite extensive studies, the spatiotemporal  characteristics of amplitude distributions of these whistler-mode waves remain incompletely characterized. We analyze nearly seven years of Van Allen Probes data combined with over nineteen years of Cluster spacecraft measurements to quantify these distributions. We find that distributions of wave amplitudes exhibit a wide and approximately log-normal core with a variable heavy tail, both dependent on geomagnetic activity and position, while time intervals between detections follow a power-law distribution indicative of temporal clustering. Intense waves occurring predominantly near the postmidnight equatorial region have average intervals of tens of minutes to hours between their detections. These findings suggest that the bursty nature of whistler-mode waves may not be fully captured by long-term averages, which are commonly used in models of radiation belt electron dynamics.