Memoirs of the Kakioka Magnetic Observatory Vol.20 No.02, p.25, March, 1984
Seasonal Variations of Geomagnetic Activity in the Northern and Southern Hemispheres
Nagai, M.
Abstract
 There is a great difference between the seasonal variations of geomagnetic activity in the northern and southern hemispheres. lt is confirmed from the analysis of data in 1959-1979 that a clear seasonal variation is observed in the difference between An and As; the difference is largest in July and smallest in December. This seasonal variation is highly correlated to AU index.
Moreover, the author discusses the solar wind and EW-component of the IMF in relation to the seasonal variation of An-As.