Exploring the Link Between Cosmic Noise Absorption Events and Whistler-Mode Waves

Ionospheric disturbances play a critical role in radio wave propagation, with implications for communication, navigation systems, and understanding space weather dynamics. Among the tools used to probe these disturbances, relative ionospheric opacity meters (riometers) provide valuable insights by measuring cosmic noise absorption (CNA). These absorption events offer a window into the diverse physical processes driving energetic electron precipitation and their subsequent impact on the ionosphere.

This study utilizes observational data from the University of Calgary network of single-frequency wide-beam (GO-Canada) riometers. A classification system was developed to segregate riometer absorption events into distinct groups based on their time-lagged signatures observed across different longitudes by stations in the East-West chain of the riometer network.

We investigate the correlation between wave occurrences measured onboard the THEMIS satellite and electron precipitation inferred from riometer absorption measurements across various event types. The goal is to determine whether these correlations align with established geophysical processes, such as precipitation driven by whistler-mode waves, and to quantify the strength and significance of these relationships. By examining the temporal and spatial patterns of cosmic noise absorption events in conjunction with satellite-based measurements, we aim to provide a detailed assessment of how well these phenomena correlate. This analysis seeks not only to validate the underlying geophysical mechanisms but also to enhance our quantitative understanding of the role of whistler-mode waves in driving electron precipitation and subsequent ionospheric disturbances.