Performance Investigation of Four Ionospheric Models in Estimating hmF2 in High‐Latitude Regions

Abstract

As a critical parameter characterizing the vertical structure of the ionosphere, the peak height of the F2 layer (hmF2) plays an essential role in frequency selection and signal propagation in high‐frequency (HF) communication systems. Accurate prediction of hmF2 is particularly important in high‐latitude regions. Based on observations from nine ionospheric stations located above 60°N, we analyze hmF2 variations and evaluate the prediction performance of four models: three IRI‐2020 sub‐models (IRI‐BSE, IRI‐AMTB, and IRI‐SHU) and the Empirical Canadian High Arctic Ionospheric Model (E‐CHAIM). The results show that: (a) hmF2 increases during high solar activity years and decreases during low solar activity years, exhibiting distinct diurnal and seasonal variations. (b) Among the four models, E‐CHAIM performs the best. Compared with the Bilitza–Sheikh–Eyfrig model (BSE), Altadill–Magdaleno–Torta–Blanch model (AMTB), and Shubin models (SHU), E‐CHAIM reduces the mean absolute error by 10.18, 11.85, and 1.77 km, and the root mean square error by 11.82, 12.61, and 1.98 km, respectively. (c) The performance of BSE and AMTB improves with increasing solar activity intensity, and the BSE model shows a more pronounced advantage during high solar activity years. It should be noted that the evaluation is conducted using monthly median hmF2 values, meaning the results primarily reflect the long‐term climatological performance of these models, while short‐term disturbances (e.g., geomagnetic activity) are largely suppressed. These findings deepen the understanding of long‐term variations in the high‐latitude ionosphere and lay a foundation for the long‐term planning of communication systems.