Variations of ionospheric TEC surrounding Great Wall Station, Antarctica

Total electron content (TEC) is an important characteristic parameter for ionospheric radiowave environment. The variations of ionospheric TEC are investigated by using GPS data observed from the surrounding of the Great Wall Station, Antarctica. Results show that the Weddell Sea Anomaly (WSA) can be observed which the TEC value is higher on nightside than dayside in summer. And the maximum values of TEC appears at 5 h LT in summer and at 11 h LT in winter and equinoxes. The silent effect of negative storm is revealed for its rare occurrence around 12 h LT. The occurring rate of TEC storm becomes higher with the rise of solar activities, and it is minimum in summer and is maximum in equinoxes. Up to 94.8% of TEC storm events are accompany with the intense disturbances of AE index, and it suggests the relativity is very strong between the auroral substorm and the TEC storm.