Affiliation:
1. Institute of Solar Terrestrial Physics SB RAS
2. Irkutsk State University
Abstract
We analyze features of current solar activity cycle 25 for the first three years of its development (2020–2022). Compared to cycle 24, the current cycle is shown to exceed the previous one in the number of sunspot groups (1.5 times), the number of flares (1.8 times), and the total flare index (1.5 times). We have found that distributions of sunspot groups during cycles 24 and 25 differ in maximum area. Solar cycle 25, unlike cycle 24, exhibits the most significant increase in the number of sunspot groups with areas up to 30 pmh and in the interval from 570 to 1000 pmh. In contrast to cycle 24, the degree of north-south asymmetry in cycle 25 is significantly reduced. This allows us to predict an increased height of cycle 25, as compared to cycle 24 (by 20–50 %), in accordance with the Gnevyshev—Ol rule, as well as the possible unimodal nature of the cycle.
Publisher
Infra-M Academic Publishing House
Reference36 articles.
1. Бородкова Н.Л. Воздействие больших и резких изменений динамического давления солнечного ветра на магнитосферу Земли. Анализ нескольких событий. Космические исследования. 2010. Т. 48, № 1. С. 1–15., Belian R.D., Gisler G.R., Cayton T.E., Christensen R.A. High-Z energetic particles at geosynchronous orbit during the great solar proton event series of October 1989. J. Geophys. Res. 1992, vol. 97, p.16897.
2. Веселовский И.С., Ермолаев Ю.И. Ионные составляющие солнечного ветра. Плазменная гелиофизика. Т. 1. M.: Физматлит, 2008. С. 313- 325., Borrini G., Wilcox J.M., Gosling J.T., Bame S.J., Feldman W.C. Solar wind helium and hydrogen structure near the heliospheric current sheet
3. a signal of coronal streamer at 1 AU. J. Geophys. Res. 1981, vol. 86, p. 4565.
4. Еселевич В.Г. Диамагнитные структуры — основа квазистационарного медленного солнечного ветра. Солнечно-земная физика. 2019. Т. 5, № 3. С. 36–49. DOI: 10.12737/szf-53201904., Borodkova N.L. The impact of large and abrupt changes in the dynamic pressure of wind energy on the Earth’s magnetosphere. Analysis of several events. Cosmic Research. 2010, vol. 48, no. 1, pp. 1–15.
5. Еселевич М.В., Еселевич В.Г. Проявление лучевой структуры пояса корональных стримеров в виде резких пиков концентрации плазмы солнечного ветра на орбите Земли. Геомагнетизм и аэрономия. 2006а. Т. 46, № 6. С. 811–824., Chen J., Fritz T.A., Sheldon R.B., Spence H.E., Spjeldvik W.N., Fennell J.F., Livi S., et al. Cusp energetic particle events: Implications for a major acceleration region of the magnetosphere. J. Geophys. Res. 1998, vol. 103, iss. A1, pp. 69–78. DOI: 10.1029/97JA02246.