Dynamical System Approach to the Study of Disturbances of Geomagnetic Field in Auroral Zone

The hypothesis suggests that chaotic behavior of the variations of geomagnetic field (VGF) in auroral zone can be described by a non-linear dynamical system witil a strange attractor. The correlation dimension of the strange attractor of underlying dynamical system is considered as a characteristic of chaotic behavior of VGF and time evolution of the correlation dimension is studied on the basis of VGF measured of the Tixie Bay and Thule observatories. The solar activity cycle time-scale and the year cycle time-scale were analyzed. The season variation of correlation dimension was found. It is in a good correlation with AE and AU indices season evolution. The estiamation of correlation dimension for the solar activity time-scale shows that underlying dynamical system in this case is differs from the case of year cycle time-scale.