Possible Pre - And Post-Earthquake Effects In The Ionosphere

This paper presents new results on the processing and analysis of EVTERCOSMOS-BULGARIA-1300 data for the quasi-static electric field and ion density in the upper ionosphere (h = 800 - 900 km) over moderate earthquakes' source regions (seismic data of World Data Center, Colorado). The most appropriate data (for satellite orbits above sources of forthcoming or just happened seismic events) were selected from more than 250 investigated cases. Thus, in order to demonstrate electric field and ion density disturbances at different latitudes, the cases of disturbances detected at polar latitude (Southern Ocean, Greenland Sea), middle latitude (South Pacific Ocean, Indian Ocean), and low latitude (Indian Ocean, South America) are shown. The paper discusses the observed effects of increase in the quasi-static electric field (in the interval 2 - 30 mV/m) and plasma density variations in the ionosphere.