A whistler study of plasmapause motion in the vicinity of sanae,Antarctica

For 4 months of synoptic records whistlers have been analyzed in two groups, high latitude (HL) whistlers with f_n?8 kHz and low latitude (LL) whistlers with f_n?8 kHz. A decrease in percentage occurrence of HL whistlers with increasing K_p is interpreted as being due to equatorwards movement of the plasmapause in the vicinity of SANAE, Antarctica (L=4). The diurnal variation in HL and LL whistler occurrence reveals an average behaviour of the plasmapause, namely, an equatorwards movement beginning at around 2000 LT followed by a return movement from 0400 LT to 0800 LT.