Forecast of the key parameters of the 24-th solar cycle

Abstract

To predict the key parameters of the solar cycle, a new method is proposed based on the empirical law describing the correlation between the maximum height of the preceding solar cycle and the entropy of the forthcoming one. The entropy of the forthcoming cycle may be estimated using this empirical law, if the maximum height of the current cycle is known. The cycle entropy is shown to correlate well with the cycle's maximum height and, as a consequence, the height of the forthcoming maximum can be estimated. In turn, the correlation found between the height of the maximum and the duration of the ascending branch (the Waldmeier rule) allows the epoch of the maximum, Tmax, to be estimated, if the date of the minimum is known. Moreover, using the law discovered, one can find out the analogous cycles which are similar to the cycle being forecasted, and hence, obtain the synoptic forecast of all main features of the forthcoming cycle. The estimates have shown the accuracy level of this technique to be 86%. The new regularities discovered are also interesting because they are fundamental in the theory of solar cycles and may provide new empirical data. The main parameters of the future solar cycle 24 are as follows: the height of the maximum is Wmax = 95±20, the duration of the ascending branch is Ta = 4.5±0.5 yr, the total cycle duration according to the synoptic forecast is 11.3 yr.

Fractal properties of stellar systems and random forces

“…Our earlier analysis of the Geneva-Copenhagen survey of FG-type dwarfs (Nordstrem et al, 2004;Holmberg et al, 2007Holmberg et al, , 2009) revealed similar fluctuations with magnitudes substantially exceeding those expected for uniform random (Poisson) space distributions to be present in the solar neighborhood, i.e., in the Galactic field. The fractal nature of the distribution of FG-type dwarfs is believed to also reflect the features of the overall distribution of local stars: we showed (Chumak & Rastorguev, 2015) that the space distribution of FG-type dwarfs in the solar neighborhood differs significantly from uniform random distribution on all available scale lengths (from 1 to 20 pc), i.e., that the stellar medium demonstrates significant and well-defined "coarse-grained structure", which can be described by the average Hausdorff dimension of D ≈ 1.23. One of the main problems in the study of the kinetics of a system of gravitating point masses is the analysis of the forces that act on test particles.…”

Solar cycle distribution of great geomagnetic storms

“…The amplitudes of solar cycle 24 predicted by researcher are quite dispersed (Obridko and Shelting 2008;Pesnell 2008;Bhatt et al 2009;Ajabshirizadeh 2011;Chumak and Matveychuk 2010;Dabas and Sharma 2010;Du and Wang 2010;Kane 2010;Wang et al, 2002Wang et al, , 2008Wang et al, , 2009). However, a dynamo model tends to predict that the amplitude of solar cycle 24 is about 90 or even at less than 90 (Jiang et al 2007).…”

Kinetic properties of fractal stellar media

“…To demonstrate significant differences of the fractal model of gravitating medium from the Poisson model generally adopted in these models numerically estimated for the local solar neighbourhood based on the results of a fractal analysis of the GCS. We adopt D ≈ 1.23 and h ≈ 1.644 for the distribution of conditional density in the fractal medium from our earlier paper (Chumak & Rastorguev, 2015).…”

“…Scrimgeour et al (2012) also provide an impressive historical review of the problem, to which we refer the interested readers. Chumak & Rastorguev (2015) analysed Geneva-Copenhagen Survey of local FG-type dwarfs (hereafter referred to as GCS) and showed that the space distribution of stars of this type, which represent a significant fraction of the local stellar population, differs significantly from uniform Poisson distribution. We also showed that the distribution of stars on GCS scales is consistent with fractal model.…”

“…

Kinetic processes in fractal stellar media are analysed in terms of the approach developed in our earlier paper (Chumak & Rastorguev, 2015) involving a generalization of the nearest neighbour and random force distributions to fractal media. Diffusion is investigated in the approximation of scale-dependent conditional density based on an analysis of the solutions of the corresponding Langevin equations.

…”