The purpose of this work lies in comparing and defining the differences between the measured values of the total electron content (TEC) and the corresponding TEC values, obtained according to global ionospheric map (GIM) data in different periods of solar activity. Methodology. The TEC and the data of global ionospheric maps (GIM) for the SULP station were used in the work, as well as the data from the Ionolab website for better clarity, where the nodal values of the TEC are essentially used, from the same global ionospheric maps (GIM). The essence of the research was to compare the values of TEC, obtained by the two above-mentioned methods in different periods of solar activity (a high solar activity – data for 2013, a low solar activity – for 2018). Results. It was determined that the differences of TEC at a low solar activity are mostly negative and reach ≈8 ТЕСU, and at the peak of solar activity both were measured and the model TEC values were basically the same and varied in range from 0.3 to 6.8 ТЕСU. Scientific novelty. The variations of the values of total electron content TEC for the SULP station in different periods of the manifestation of solar activity were obtained and given and it was established that at a low solar activity the measured TEC values prevail over the model values by more than 20 % and do not exceed ≈6 ТЕСU, and at a high solar activity both the model and the measured values are practically the same and range approximately from 4 to 31 TECU. Practical significance. The results obtained can be used for constructing regional maps and the velocities and direction of ionospheric stain movements, as well as in solving some issues for a certain region.
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