Characterizing perturbed ionospheric total electron content configurations using the Shannon information content

Anomalous or perturbed ionospheric conditions can have adverse consequences for many space -related applications, including global navigation satellite and communication systems. As such, technical capability to detect and characterize perturbed ionospheric configurations is a valuable tool for routine space environment monitoring. In this work, we formulate a mathematical scheme that uses a concept borrowed from information theory, known as the Shannon information content (SIC), for characterizing anomalous/perturbed ionospheric total electron content (TEC) configurations. This approach has an advantage that the scheme for calculating SIC is versatile due to its adjustable complexity, while consistently invoking a universal measure of information (bits). In addition to theoretical formulation, we also performed an empirical assessment by using global ionospheric maps (GIM) from 2011-2016 in order to test the overall capacity of this information theory -based approach. The assessment indicates that the SIC values worldwide exhibited a moderate statistical correlation with the peak Dst and Kp values attained during individual geomagnetic storms, with correlation coefficients in the 0.38-0.57 range. A special case examination using the 17 March 2015 Saint Patrick's Day geomagnetic storm also shows that the SIC values over North America increased promptly at the start of the storm. These findings suggest that SIC can help characterize anomalous/perturbed ionospheric configurations that are either widespread globally or localized over a particular sector, potentially complementing several existing ionospheric perturbation indices (e.g. W -index, I -scale, IsUG, DIX, DIXSG, ROTI). (c) 2024 COSPAR. Published by Elsevier B.V. All rights reserved.