Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 6a9c168032807fdbab8763a1 10.12737/stp-123202605 rggisi Results of current research Results of current research Results of current research Variations in parameters of low-frequency signals on a mid-latitude radio path during geomagnetic storms caused by high-speed solar wind streams from coronal holes Variations in parameters of low-frequency signals on a mid-latitude radio path during geomagnetic storms caused by high-speed solar wind streams from coronal holes Соловьева Мария Сергеевна Solovieva Maria Sergeevna rozhnoi@ifz.ru Коркина Галия Мугтасимовна Korkina Galiya Mugtasimovna gkor@emsd.ru Булатова Надежда Руслановна Bulatova Nadezhda Ruslanovna geofizik@emsd.ru Институт физики Земли им. О.Ю. Шмидта РАН Москва Россия Schmidt Institute of Physics of the Earth RAS Moscow Russian Federation Камчатский филиал ФИЦ «Единая геофизическая служба РАН» Петропавловск-Камчатский Россия Federal Research Center “Unified Geophysical Service RAS”, Kamchatka Branch Petropavlovsk-Kamchatsky Russian Federation Камчатский филиал ФИЦ «Единая геофизическая служба РАН» Петропавловск-Камчатский Россия Federal Research Center “Unified Geophysical Service RAS”, Kamchatka Branch Petropavlovsk-Kamchatsky Russian Federation 19 09 2026 19 09 2026 12 3 45 53 07 10 2025 16 02 2026 © 2026 Соловьева М.С., Коркина Г.М., Булатова Н.Р. © 2026 Solovieva M.S., Korkina G.M., Bulatova N.R. 2026 Соловьева Мария Сергеевна, Коркина Галия Мугтасимовна, Булатова Надежда Руслановна Solovieva Maria Sergeevna, Korkina Galiya Mugtasimovna, Bulatova Nadezhda Ruslanovna https://zh-szf.ru/en/nauka/publications/6a9c168032807fdbab8763a1/view

Variations in the amplitude and phase of a mid-latitude low-frequency signal from the JJY (40 kHz) transmitter were analyzed during four geomagnetic storms in 2021 and 2025, which were caused by high-speed solar wind streams from coronal holes creating corotating interaction regions. The analysis has shown that nighttime anomalous disturbances in the amplitude and phase were observed for three days during a magnetic storm. The negative amplitude anomalies of the signal ranged from 4.5 to 21 dB; phase anomalies were from 41° to 124°. The sign of the phase anomalies was different on different days. We recorded both positive and negative phase anomalies, as well as wave-like disturbances with a transition from negative to positive anomalies. A statistical relationship was found between the value of the phase anomaly and the intensity of geomagnetic disturbances. The correlation coefficient with the Dst index was –0.39. The relationship between phase anomalies and the AE index is higher; the correlation coefficient in this case was 0.53. No statistical relationship was observed between geomagnetic activity and the anomaly for the sub-ionospheric signal amplitude.

Variations in the amplitude and phase of a mid-latitude low-frequency signal from the JJY (40 kHz) transmitter were analyzed during four geomagnetic storms in 2021 and 2025, which were caused by high-speed solar wind streams from coronal holes creating corotating interaction regions. The analysis has shown that nighttime anomalous disturbances in the amplitude and phase were observed for three days during a magnetic storm. The negative amplitude anomalies of the signal ranged from 4.5 to 21 dB; phase anomalies were from 41° to 124°. The sign of the phase anomalies was different on different days. We recorded both positive and negative phase anomalies, as well as wave-like disturbances with a transition from negative to positive anomalies. A statistical relationship was found between the value of the phase anomaly and the intensity of geomagnetic disturbances. The correlation coefficient with the Dst index was –0.39. The relationship between phase anomalies and the AE index is higher; the correlation coefficient in this case was 0.53. No statistical relationship was observed between geomagnetic activity and the anomaly for the sub-ionospheric signal amplitude.

 sub-ionospheric radio signals lower ionosphere geomagnetic storms midlatitudes sub-ionospheric radio signals lower ionosphere geomagnetic storms midlatitudes The work was performed under Government Assignment at IPE RAS The work was performed under Government Assignment at IPE RAS

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