Иркутский государственный университет
Иркутск, Россия
Иркутск, Россия
Иркутск, Россия
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.
solar activity cycle, sunspots, solar flares, north-south asymmetry
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23. Obridko V.N., Nagovitsyn Yu.A. Solnechnaya aktivnost’, tsiklichnost’ i metody prognoza [Solar activity, Cyclicity and Forecast Techniques]. Saint Petersburg, VVM Publ., 2017, 466 p. (In Russian).
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27. Vitinsky Yu.I., Kopecky M., Kuklin G.V. Statistika pyatnoobrazovatelnoi deyatelnosti Solntsa [Statistics of sunspot-forming activity of the Sun]. Moscow, Nauka Publ., 1986, 296 p. (In Russian).
28. URL: https://www.sidc.be/silso/forecasts (accessed February 15, 2023).
29. URL: https://www.sidc.be/silso/monthlyhemisphericplot (accessed February 15, 2023).
30. URL: https://www.swpc.noaa.gov/products/solar-cycle-progression (accessed February 15, 2023
