Determining of the Ionosphere parameters on space weather variations

The method of incoherent scattering of radio waves allows to experimentally determine both regular variations of the basic parameters of ionosphere, and their behavior during disturbances of various origin. The parameters of the technique for determination of a quiet ionosphere is considering the fact that their time variations occur very slowly and the main maximum of electron density (N) is distinctly expressed. In the topside ionosphere the plasma concentration is exponentially decreasing with the increase of the altitude. During the perturbations, the dependence between the scattering cross-section and the ionosphere parameters is retained, but the altitude and time dependences of the scattering medium correlation function can differ from them under the undisturbed conditions. The coherent echo, reconfiguration of the F2 layer changing the altitude parameters variations can be observed in the disturbance mode. This resulted in modification of the io! nosphere parameters determining technique under the availability of disturbances in the ionosphere. The results of the experimental measurements during the magnetic storms on 30 May 2003 and 9-10 November 2004 are provided. The altitude dependences of the correlation and the spectral function, cross sections and drift velocities of the ionosphere plasma, time and altitude distributions of the scattered signal power are presented. The comparison of the obtained results and their correlation with space weather characteristics is performed. © 2007 Begell House, Inc.