Statistical analysis and modelling of sporadic E layer over Europe

• Published in: Advances in space research 2019-09, Vol.64 (6), p.1243-1255
• Main Authors: Zaalov, N.Y., Moskaleva, E.V.
• Format: Article
• Language: English
• Subjects: GIRO network; HF wave propagation; Ionogram simulations; NIM-RT software; Sporadic E layer; Statistic analysis
• ISSN: 0273-1177; 1879-1948
• DOI: 10.1016/j.asr.2019.06.034

•Spatial and temporal variability of Es layer top frequency was analyzed.•Statistic Es layer top frequency at different seasons and phase of solar activity was performed.•The maps of the distribution of Es layer top frequency were produced.•The “cloud” model of Es layer was implemented in NIM-RT propagation model for ionogram simulations. This paper describes a study of the daily and yearly variability of one of the main characteristics of sporadic E layers (Es), the critical frequency (foEs). Our analysis is based on ionograms recorded by GIRO network ionosondes. The study estimates the spatial and temporal variability of the Es layer parameters and generates their statistics at different seasons and phases of the solar cycle. In turn, the statistics of the Es layer parameters can provide an assessment of the capability of the HF propagation forecasting. Further, maps of the distribution of Es layer critical frequency are produced. This paper implements the “cloud” model of Es layer in HF propagation model (Northern Ionosphere Model & Ray Tracing, NIM-RT) that can accurately reproduce many features observed in experimental measurements. Within this framework, a number of vertical sounding ionograms with the presence of Es layer are simulated based on the NIM-RT software.