Ionospheric response to Tuva earthquakes of December 27, 2011 and February 26, 2012

Ionospheric responses to the earthquakes in Tuva Republic of December 27, 2011 (Mw=6.7) and February 26, 2012 (Mw=6.6) were investigated using GPS sounding data. The responses to both earthquakes are poorly defined. At particular receiver-satellite beams the total electron content disturbances with ~10 min period are registered at 500-800 km from epicenters. The horizontal velocity of traveling disturbance is about 200 m/s that is close to the sound velocity in the lower atmosphere.