ИСТИНА

Precipitations of electrons with energies of tens to hundreds keV from the outer radiation belt (ORB) were investigated in American, European and Siberian longitudinal sectors during two solar cycles from 2001 to 2018. The precipitations affect mainly the upper atmosphere and the bottomside ionosphere (D and E layers) at middle to high latitudes. Intense precipitations during magnetic storms can disturb the ionosphere globally. It was found that maximal precipitations are observed during solar maxima and in the middle of declining phases. The lowest fluxes were detected in the deep minimum of 2009. In general, electron fluxes are weaker during the current 24th solar cycle, than during the previous one. The ORB precipitations are situated at highest latitudes during the deepest solar minimum in the year 2009. During the solar maxima, the ORB shifts equatorward. The ORB location varies around a secular trend. In the American sector, the ORB shifts poleward by ~1 deg. In the European sector, the location did not change. A strong equatorward shift of about 3 – 4 degrees of ORB precipitations was found in the Siberian sector. This fact might indicate additional changes in geomagnetic field, which are accelerated in the current solar cycle.