ИСТИНА

The fractal structure of magnetic patterns in photosphere was established almost immediately after introduction into the practice of investigation of the panoramic magnetographs. The study of fractal characteristics of the solar magnetic fields is still going on. The report presents a brief overview of the key concepts and methods of fractal analysis in application to problems of solar physics. On the example of two well-studied active regions AR10486 and AR10488 some of the results of the changes of fractal properties of the magnetic structures are demonstrated. In particular, it is shown that: 1.Average (by time) values of the fractal dimension of the North and South of the polarities of the magnetic field in the active regions can differ considerably; 2.The time series of the fractal dimension of North and South polarities demonstrate variations with significant amplitude and different quasi periods. The nature and role of these variations in the evolution of active regions remains unclear; 3.Variations of the fractal dimension show an unstable correlation at different time intervals for AR10486 and good correlation for AR10488. The reason for this phenomenon is also not clear; 4.The general character of these variations weakly depends or, practically, does not fully depend on the chosen time step, that is, the time-series variations demonstrate temporary stochastic self-similarity; 5.On the 1-min data quasi 5-minute rhythm is clearly visible on the background of a stochastic process. It points out that the 5-minute oscillations are connected with scaling indicators of strong local magnetic fields of active regions; 6.Significant relationship between variations in fractal dimensions and eruption processes is not found. Before large flares the significant jumps in the amplitude of the variations are found, but these facts require confirmation on a larger volume of data.