TEC variations during the sudden stratospheric warming of winter 2012/2013, according to GPS-sounding data

We examined variations of the total electron content (TEC) during the “major” sudden stratospheric warming (SSW) in the Asian part of Russia in winter 2012/2013. Data from the dual-frequency GPS receivers deployed at ISTP SB RAS were used for the study. During the main phase of the SSW and during several days after it, there is an increase in intensity of TEC wave variations with a period of up to 60 min in the ionosphere. The intensity of TEC variations observed during the recovery of atmospheric circulation is comparable with the intensity of variations recorded during weak geomagnetic disturbances.