ИСТИНА

Two approaches to using the GNSS data for the construction of new perturbation indices of the ionospheric plasma which take into account the perturbation on the spatial scale less than 2° are suggested. The first approach is based on the data of high orbital radio tomography (HORT). Considering the deviations of the electron density distributions provided by HORT from their averages over an undisturbed period, we construct the HORT- indices of ionospheric perturbations (perturbation maps and integral indices obtained by spatial averaging of the maps). The second approach is based on the analysis of the initial slant TEC data. Here, by applying special processing procedures, we separate the variational varying (quasi wavelike) component and then locally average these variations over space by the least squares technique. Just as in the first approach, the perturbation maps serve as a basis for constructing integral indices. The comparison of the constructed indices with the space weather parameters and geomagnetic perturbations demonstrates the high sensitivity of the first to space weather factors. The effect of the delay of the ionospheric perturbation relative to the geomagnetic disturbance on the different scales of ionospheric variations is revealed.