Relation Between Sporadic E and Magnetic Activity During the IGY

Abstract

The paper deals with an analysis of the behaviour of sporadic E on disturbed days and quiet days during the IGY period. Data from Wilkes (geomag. lat. 77·9°S), Halley Bay (geomag. lat. 65·8°S), Hobart (geomag. lat. 52°S), Townsville (geomag. lat. 28·5°S) and Kodaikanal (geomag. lat. 0·6°N) representing the very high latitude, the auroral, the high latitude temperate, low latitude temperate and the equatorial zones have been considered. The analysis has shown that at station near the pole and high latitude temperate station the occurrence is less on disturbed days than on quiet days, whereas at the auroral station is more on disturbed days than on quiet days. At the low latitude temperate station and at equatorial station no such clear indication is found. The distribution of the frequency of disappearance of Es indicate that lower frequencies of disappearance tend to occur more at temperate and high latitude zones and higher frequencies at the equatorial zone. On disturbed days, the occurrence of Es over the whole range of frequencies is less than on quiet days at very high latitude and high latitude temperate station, whereas at the auroral station the position is reversed. At low latitude stations, no clear indication is observed. The cumulative distribution of Es shows that the Phillips Rule (Phillips, 1947) is applicable above the most probable value of the occurrence of fEs for both quiet and disturbed days individually. The diurnal and seasonal variation of fEs are described.