Solar Activity Index for the Critical Frequency of the E Layer
- Authors: Deminov M.G.1, Badin V.I.1, Deminov R.G.2, Nepomnyashchaya E.V.1
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Affiliations:
- Pushkov Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation
- Kazan Federal University
- Issue: Vol 63, No 6 (2023)
- Pages: 815-821
- Section: Articles
- URL: https://journals.rcsi.science/0016-7940/article/view/232923
- DOI: https://doi.org/10.31857/S0016794023600424
- EDN: https://elibrary.ru/PWMGLH
- ID: 232923
Cite item
Abstract
The index P = (F1 + F81)/2 is the optimal solar activity index for the critical frequency of the E layer, foE, where F1 and F81 are the flux of radio emission from the Sun at a wavelength of 10.7 cm on a given day and the 81-day average value of this flux centered on a given day. Therefore, to calculate F81 on a given day, knowledge of F1 is needed not only on this and previous days, but also 40 days in advance. Instead of index F81, in problems on short-term forecasting of this index, it is possible to use F(27, 81), the weighted average solar activity index with a characteristic time of 27 days for the current and previous 80 days. Therefore, to calculate F(27, 81), knowledge of F1 on this and previous days suffices. This paper presents the first estimates of the effectiveness of such a replacement for foE. For this, changes in the accuracy of calculating foE were analyzed when index P is replaced by P * = (F1 + F(27, 81))/2 in empirical models constructed from foE data of ionospheric stations in the daytime at middle and subauroral latitudes for 1959–1995. It turns out that the P and P * indices are almost equivalent for calculating foE based on the empirical models constructed at these latitudes: the difference in the coefficients of variation for foE does not exceed 0.3% in each season at different solar cycle phases. Therefore, P * can be recommended for use in short-term foE forecasting problems, since it is based on indices F1 for the current and previous days, as opposed to index P, which requires a forecast 40 days in advance to calculate F1.
About the authors
M. G. Deminov
Pushkov Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation
Email: deminov@izmiran.ru
108840, Moscow, Troitsk, Russia
V. I. Badin
Pushkov Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation
Email: deminov@izmiran.ru
108840, Moscow, Troitsk, Russia
R. G. Deminov
Kazan Federal University
Email: deminov@izmiran.ru
Kazan, Russia
E. V. Nepomnyashchaya
Pushkov Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation
Author for correspondence.
Email: deminov@izmiran.ru
108840, Moscow, Troitsk, Russia
References
- – Антонова Л.А., Иванов-Холодный Г.С., Чертопруд В.Е. Аэрономия слоя E (учет вариаций УФ-излучения и геомагнитных возмущений). М.: Янус, 168 с. 1996.
- – Гальперин Ю.И., Сивцева Л.Д., Филиппов В.М., Халипов В.Л. Субавроральная верхняя ионосфера. Новосибирск: Наука, Сиб. отд-ние, 192 с. 1990.
- – Гмурман В.Е. Теория вероятностей и математическая статистика. М.: Высш. шк., 479 с. 2003.
- – Деминов М.Г., Михайлов А.В., Михайлов В.В., Шубин В.Н., Цыбуля К.Г. Ионосферное моделирование и прогнозирование / Системный мониторинг ионосферы. Сб. науч. тр. (Ред. Н.Г. Котонаева). М.: ФИЗМАТЛИТ. С. 286−343. 2019.
- – Деминов М.Г. Индекс солнечной активности для критической частоты E-слоя на средних широтах // Геомагнетизм и аэрономия. Т. 62. № 2. С. 206−210. 2022а. https://doi.org/10.31857/S0016794022020055
- – Деминов М.Г. Эффективный индекс солнечной активности для краткосрочного прогноза среднего индекса этой активности // Геомагнетизм и аэрономия. Т. 62. № 3. С. 302–306. 2022б. https://doi.org/10.31857/S0016794022030051
- – Деминов М.Г., Рогов Д.Д. Индекс солнечной активности для критической частоты E-слоя на субавроральных широтах // Геомагнетизм и аэрономия. Т. 62. № 5. С. 627– 634. 2022. https://doi.org/10.31857/S0016794022050042
- – Нусинов А.А. Детерминированная модель среднеширотного и экваториального E-слоя (описание и сравнительные характеристики точности) // Ионосферные исслед. № 44. С. 94–99. 1988.
- – Bilitza D. IRI the international standard for the ionosphere // Adv. Radio Sci. V. 16. P. 1–11. 2018. https://doi.org/10.5194/ars-16-1-2018
- – Kouris S.S., Muggleton L.M. Diurnal variation in the E-layer ionization // J. Atmos. Terr. Phys. V. 35. P. 133–139. 1973a. https://doi.org/10.1016/0021-9169(73)90221-3
- – Kouris S.S., Muggleton L.M. World morphology of the Appleton E-layer seasonal anomaly // J. Atmos. Terr. Phys. V. 35. 141–151. 1973b. https://doi.org/10.1016/0021-9169(73)90222-5
- – Nava B., Coisson P., Radicella S.M. A new version of the NeQuick ionosphere electron density model // J. Atmos. Sol.-Terr. Phy. V. 70. P. 1856–1862. 2008. https://doi.org/10.1016/j.jastp.2008.01.015
- – Nikolaeva V., Gordeev E. SPAM: Solar spectrum prediction for applications and modeling // Atmosphere. V. 13, 226. 2023. https://doi.org/10.3390/atmos14020226
- – Nusinov A.A. Seasonal-latitudinal variations of ionospheric E-layer critical frequencies dependence on solar activity in empirical models // Adv. Space Res. V. 37. P. 433–436. 2006. https://doi.org/10.1016/j.asr.2005.11.017
- – Nusinov A.A., Kazachevskaya T.V., Katyushina V.V. Solar extreme and far ultraviolet radiation modeling for aeronomic calculations // Remote Sens. V. 13, 1454. 2021. https://doi.org/10.3390/rs13081454
- – Pavlov A.V., Pavlova N.M. Comparison of NmE measured by the boulder ionosonde with model predictions near the spring equinox // J. Atmos. Sol.-Terr. Phy. V. 102. P. 39–47. 2013. https://doi.org/10.1016/j.jastp.2013.05.006
- – Richards P.G., Fennelly J.A., Torr D.G. EUVAC: A solar EUV flux model for aeronomic calculations // J. Geophys. Res. V. 99. P. 8981–8992. 1994. https://doi.org/10.1029/94JA00518
- – Richards P.G., Woods T.N., Peterson W.K. HEUVAC: A new high resolution solar EUV proxy model // Adv. Space Res. V. 37. P. 315–322. 2006. https://doi.org/10.1016/j.asr.2005.06.031
- – Solomon S.C., Qian L. Solar extreme-ultraviolet irradiance for general circulation models // J. Geophys. Res. V. 110. A10306. 2005. https://doi.org/10.1029/2005JA011160
- – Solomon S.C. Numerical models of the E-region ionosphere // Adv. Space Res. V. 37. P. 1031–1037. 2006. https://doi.org/10.1016/j.asr.2005.09.040
- – Taylor J.R. An introduction to error analysis. Mill Valley, CA: Univer. Sci. Books, 270 p. 1982.
- – Titheridge J.E. Re-modeling the ionospheric E region // Kleinheubacher Berichte. V. 39. P. 687–696. 1996.
- – Wrenn G.L. Time-weighted accumulations ap(τ) and Kp(τ) // J. Geophys. Res. V. 92. P. 10125–10129. 1987. https://doi.org/10.1029/JA092iA09p10125
- – Yang Z., Ssessanga N., Tran L.T., Bilitza D., Kenpankho P. On improvement in representation of foE in IRI // Adv. Space Res. V. 60. P. 347–356. 2017. https://doi.org/10.1016/j.asr.2016.11.008
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