REGULARITIES AND CHARACTERISTICS OF GEOMAGNETIC DAILY VARIATION DURING POLAR DAY AND POLAR NIGHT ON THE ZHONGHAN STATION OF ANTARCTICA, CHINA

The regularities and characteristics of geomagnetic daily variation (Sq, Sq, SD) in the polar night (May, June, July) and polar days (Nov., Dec.) have been analyzied and studied by using geomagnetic data obtained at Zhongshan station of Antarctica in 1991. The results show that double peak of Sq in the polar day was muh more outstanding than that ones in the polay night. Sq is geomagnetic quite day variation at the polar region superposed on the Sq. The amplitudes of Sq. Sq and SD in the polar night are less than that ones in the polar days. SD is three fourth of amplitudes for polar day they are only one third of amplitudes for polar day. Maybe the wave radiation of sun decreases when sun radiates direct to northern hemisphere in the polar nigh; the wave radiation of sun increase when that to southern hemisphere in the polar dny.So, it causes the change of equlvalent current intensity in ionosphere.