Two‐Dimensional Imaging of the Ionospheric Vertical Total Electron Content Over East Africa

Total electron content (TEC) is a crucial parameter for monitoring space weather effects, typically obtained from a network of Global Navigation Satellite System (GNSS) receivers. However, the uneven distribution of the available GNSS receivers in East Africa results in limited TEC data coverage. To address this challenge, a novel hybrid approach was introduced that combined the finite element method (FEM) with the ensemble Kalman filter (EnKF) technique to construct detailed vertical total electron content (VTEC) maps from limited observations. This innovative method enhanced the spatial and temporal resolution of TEC maps, offering a significant improvement over existing methods by capturing local VTEC variations with higher precision. The study investigated VTEC characteristics over East Africa during high (2014) and low (2018) solar activity years, revealing notable diurnal and seasonal VTEC variations, with peak values during equinoxes and significant disruptions during geomagnetic storms. The developed VTEC maps were validated against GNSS receiver data, showing a strong correlation (0.98–0.99) with actual measurements. This suggested that the FEM‐EnKF approach provides a reliable and accurate tool for estimating VTEC over the East African region, particularly in areas with sparse data coverage, thereby supporting global navigation and space weather monitoring applications.