Solar-Terrestrial Physics Solar-Terrestrial Physics Solar-Terrestrial Physics 2500-0535 109300 10.12737/stp-114202504 Results of current research Results of current research Results of current research Effects of the May 10–13, 2024 magnetic storm in the Asian region of Russia from ionospheric sounding with a continuous chirp signal Effects of the May 10–13, 2024 magnetic storm in the Asian region of Russia from ionospheric sounding with a continuous chirp signal https://orcid.org/0000-0002-1371-6855 Пономарчук Сергей Николаевич Ponomarchuk Sergey Nikolaevich spon@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 https://orcid.org/0000-0002-7691-6168 Золотухина Нина Александровна Zolotukhina Nina Aleksandrovna zolot@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 https://orcid.org/0000-0001-5120-1150 Куркин Владимир Иванович Kurkin Vladimir Ivanovich kurkin@iszf.irk.ru

доктор физико-математических наук;

doctor of physical and mathematical sciences;

 https://orcid.org/0000-0003-2254-6138 Белинская Анастасия Юрьевна Belinskaya Anastasiya Yuryevna belinskayaay@ipgg.sbras.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 https://orcid.org/0000-0002-6472-5006 Грозов Виктор Петрович Grozov Viktor Petrovich grozov@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 https://orcid.org/0000-0002-1120-870X Ойнац Алексей Владимирович Oinats Aleksey Vladimirovich oinats@iszf.irk.ru

кандидат физико-математических наук;

candidate of physical and mathematical sciences;

 Поддельский Алексей Игоревич Poddelsky Aleksey Igorevich podd-igor@yandex.ru https://orcid.org/0000-0002-9112-6535 Подлесный Алексей Витальевич Podlesnyi Aleksey Vitalyevich pav1986@rambler.ru https://orcid.org/0000-0002-8732-511X Цедрик Марк Владиславович Cedrik Mark Vladislavovich mark7cedrick@gmail.com Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation Институт нефтегазовой геологии и геофизики им. А.А. Трофимука СО РАН Новосибирск Россия Trofimuk Institute of Petroleum Geology and Geophysics SB RAS Novosibirsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation Институт космофизических исследований и распространения радиоволн ДВО РАН Паратунка Россия Institute of Cosmophysical Research and Radio Wave Propagation FEB RAS Paratunka Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation Институт солнечно-земной физики СО РАН Иркутск Россия Institute of Solar-Terrestrial Physics SB RAS Irkutsk Russian Federation 10 12 2025 10 12 2025 11 4 14 28 15 04 2025 02 06 2025 https://naukaru.ru/en/nauka/article/109300/view

Effects of the May 10–13, 2024 extreme magnetic storm in the Asian region of Russia have been studied using experimental data from vertical and oblique sounding of the ionosphere with a continuous chirp signal. Features of ionospheric disturbances induced by the magnetic storm have been revealed: the long-lasting negative ionospheric disturbance that was manifested as a significant decrease in F2-layer critical frequencies and maximum observed frequencies of radio paths; the absence of HF signal reflections from F-region due to sporadic Es layer and increased absorption of HF signals; recording of auroral and oblique Es layers; the long-lasting G-effect during local daytime during which the F1-layer critical frequency exceeded the F2-layer critical frequency; the dusk enhancement of electron density and F2-layer peak height. We have found a correlation of variations in ionospheric parameters and the maximum observed frequencies of HF radio wave propagation modes with spatial location of the main ionospheric trough and the equatorial boundary of the diffuse electron precipitation zone.

Effects of the May 10–13, 2024 extreme magnetic storm in the Asian region of Russia have been studied using experimental data from vertical and oblique sounding of the ionosphere with a continuous chirp signal. Features of ionospheric disturbances induced by the magnetic storm have been revealed: the long-lasting negative ionospheric disturbance that was manifested as a significant decrease in F2-layer critical frequencies and maximum observed frequencies of radio paths; the absence of HF signal reflections from F-region due to sporadic Es layer and increased absorption of HF signals; recording of auroral and oblique Es layers; the long-lasting G-effect during local daytime during which the F1-layer critical frequency exceeded the F2-layer critical frequency; the dusk enhancement of electron density and F2-layer peak height. We have found a correlation of variations in ionospheric parameters and the maximum observed frequencies of HF radio wave propagation modes with spatial location of the main ionospheric trough and the equatorial boundary of the diffuse electron precipitation zone.

 ionospheric disturbances radio wave propagation magnetosphere ionosphere main ionospheric trough diffuse electron precipitation ionospheric disturbances radio wave propagation magnetosphere ionosphere main ionospheric trough diffuse electron precipitation The work was financially supported by the Ministry of Science and Higher Education of the Russian Federation (Projects FWSE-2021-0002, FWZZ-2022-0019) The work was financially supported by the Ministry of Science and Higher Education of the Russian Federation (Projects FWSE-2021-0002, FWZZ-2022-0019)

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