Equatorial Ionization Anomaly Crest Position and Width Modeling

Knowing the locations and widths of the Northern and Southern Equatorial Ionization Anomaly (EIA) crests is essential for characterizing the spatiotemporal and solar activity variations of the low latitude ionosphere. The crest region is characterized by strong electron density gradients and plasma instabilities that significantly affect Global Navigation Satellite System (GNSS) applications. Despite their significance, a comprehensive characterization and modeling of EIA crest positions and widths remain limited. This study addresses this gap, for the first time, by analyzing and modeling the global spatiotemporal and solar activity variations in crest positions and widths using 6 years (2019–2024) of COSMIC‐2 radio occultation‐derived peak electron density (NmF2) data. The results show that crest positions and widths exhibit clear diurnal, semi‐diurnal, and annual patterns. Although the crest positions and widths show a weak linear correlation with solar activity, their longitudinal variations are influenced by geomagnetic declination and the interaction between wave number 3 diurnal tides and planetary wave. The results of the analysis are used to create empirical Neustrelitz Ionosphere Crest Models (NICM). The models yield mean differences of approximately 0°, with standard deviations of about 3° for crest positions and 2° for widths, relative to observed data. Despite mismodeling deviations around 3°, the models offer a reasonable representation of crest positions and width validated by altimeter‐based vertical TEC measurements over the oceans. These models can be used to improve current ionospheric TEC and F2‐layer maximum electron density models, applicable for improving terrestrial communications and GNSS positioning and navigation.