Low Temperate Zone Sporadic-E: Seasonal and Diurnal Variations at Rarotonga

Abstract

The seasonal variations of strong E s occurrence as a function of diurnal period have been obtained for the Pacific station of Rarotonga (21 0 .2 S). The seasonal characteristics depend markedly on local time with afternoon Es activity showing large deviations-equinoxial enhancements and summer peaks occurring before solstice-from those expected from the formation processes currently understood.