Kuznetsov V.V., Cherneva N.V.

Institute of Cosmophysical Research and Radio Wave Propagation FEB RAS
e-mail: nina@ikir.kamchatka.ru

We report on the study of the effects in atmospheric electric field (AEF) which were carried out at "Paratunka" geophysical observatory. The days under analysis were the days with fair weather conditions when at the moments of passing of geomagnetic disturbances the AEF EZ value decrease was observed simultaneously with Forbush decrease of galactic cosmic ray (GCR) flux intensity. It was determined that Forbush decreases of GCR intensity appear during the registration of air electric conductivity. In the analysis of AEF observations solar terminator effects were discovered. AEF value regularly increases at the moments of sunrise. At sunset this effect appears more rarely and weaker. It was shown that morning terminator effects do not appear in conductivity variations at the ground level whereas for evening terminator the AEF variation change is quite regular. Forbush decrease effect in AEF amounts to 80% of the average field value, which is 10 times as much as the percentage of GCR intensity decrease.