Using of global and regional ionospheric maps to study of the preseismic ionosphere modification

In this paper the analysis of the ionospheric total electron content (TEC) variations obtained by using of GPS measurements before strong earthquakes is presented. For this aim we used both the TEC data from the nearest to the earthquake epicenter GPS stations and TEC maps (global maps at the IONEX format and regional maps with high spatial-temporal resolution). The general peculiarities of the observed effects are described.