AN ANALYSIS OF THE IONOSPHERIC DISTURBANCES DURING A MAGNETIC STORM OBSERVED WITH A GPS NETWORK

With a GPS network located in the East Asia and Australia sector, a anal-ysis method to estimate the rapid variation of TEC is proposed and applied to the investigation of the ionospheric responses to the July 14-18, 2000 geomag-netic storm. The analyzed result reveals the perturbation structure around the geomagnetic equator during the storm. The temporal and spatial changes of TEC are obtained and discussed. The results manifest most of the information of the storm-time regional TEC variation in spite of the disadvantageous influences, such as the asymmetrical distribution of the GPS network, the shortfall of observation data, the discontinuous variety of data and etc. It is shown that the method we used is satisfactory in studying the small scale ionospheric disturbance such as the perturbations during ionospheric storms.