Tec variation in the ionosphere during the seismic activity period in 2009 in Italy

This paper investigated change of electronic concentration in ionospheres layer of the Earth in seismic activity is considered, and also during earthquake on April, 6th, 2009 by magnitude 6,3 points under the Richter scale. The determination of electronic concentration is considered from March, 1st, till April, 26th, 2009 spent on the measured radionavigating parametres of navigating satellite system GPS.