Ionospheric total electron content behaviour during November 1997 storm

The GPS observations carried out by IGS stations were used to study TEC changes on global scale during storm on 22 November 1997. We analysed the spatial and temporal TEC changes through time series at selected sites and maps for different sectors of northern hemisphere in comparison with the quiet TEC variations. The positive effect in the behaviour of TEC during the storm was prevailed on global scale at middle latitudes. The strong negative effect was observed at auroral and subauroral latitudes only over America. TEC behaviour on first stage of storm was similar to TEC development of storm on 10 January 1997. The long positive effect is the significant feature in viewed storm, which is probably due to the long duration and complex development of the storm.