Physics of auroral phenomena : proceedings of the 37th Annual seminar, Apatity, 25 - 28 February, 2014 / [ed. board: A. G. Yahnin, N. V. Semenova]. - Апатиты : Изд-во Кольского научного центра РАН, 2014. - 125 с. : ил., табл.

Classification approach to the analysis o f magnetic disturbances Fig. 2 shows the results of counting the number of satisfactory restoration for pairs of indices ASY-AU and ASY-AL. The x axis marked a sequence numbers of events and the у axis - number of satisfactory restorations. In gray shows the results for pair ASY-AU, in black - for pair ASY-AL, [ оASY-AUSASY-AL Event number Figure 2. The number of satisfactory restored cases of each considered event When considering the obtained results it can be found that for pairs ASY-AU and ASY-AL exist events restored equally well (9, 29) and equally poor (11, 15, 16). But for most events there is a "balance shift" of AU index to index AL: if for pair ASY-AU a number of satisfactory restorations of specific event is large, at the same time for pair ASY-AL for the same event the number of satisfactory restorations will be small, and vice versa. According to Fig. 2, for the greatest number of cases the "shift" takes place in pair ASY-AL direction. Thus the good connection of asymmetric ring current with westward electrojet obtained in papers [Grafe et. al., 1997; Barkhatov et. al., 2007; Barkhatov et. al, 2008] and confirmed in the present study may be explained by the fact that within geomagnetic storm main phase a westward electrojet usually developed intensively then eastward electrojet. Under the assumption that the asymmetric ring current forms with eastward and westward electrojets a single ionospheric-magnetospheric current system, it can be concluded that the presence o f "balance shift" for pairs ASY- AU and ASY-AL indicates the degree of each electrojet development. In other words, if one of electrojets developed significantly, then the other has a poor development. This may mean that the eastward and westward electrojets have the same energy budget. 4. Classification approach to analyzing the connection between magnetic disturbances in the auroral region and magnetic disturbance at middle and low latitudes Considered in this paper geomagnetic storms have different intensity and the main phase duration. Despite the fact that the time behavior of Dst index for all events considered above have the "classical" form, the dynamics o f symmetric and asymmetric ring current parts and auroral electrojets within different events differs substantially. To establish the influence degree of SYM, ASY, AU and AL dynamics for the presence or absence o f nonlinear connection between corresponding indices, it has been carried out the classification of all events by the Kohonen neural network. The classification was carried out by two parameters that are consistent with studied pairs of indices: SYM and AU; SYM and AL; ASY and AU; ASY and AL. In each experiment a neural network was proposed to divide all 30 events in the two classes. Fig. 3 shows an example of events classification under parameters ASY, AL. According to the results, the first class in the main has short-time events with low intensity, and the second class - long-time and intensive events. ASY First class Second class Figure 3. Example of 30 geomagnetic events classification under ASY, AL parameters 8