Book Description
Previous research results on high latitude sporadic E are surveyed, and replotted and displayed in Corrected Geomagnetic Latitude (CGL) AND Corrected Geomagnetic Time (CGT) and related to current research results. Patterns of occurrence of sporadic E are developed, showing percent of time of occurrence in location in the CGL/CGT coordinate system, in terms of sporadic E top frequency (fE sub s) and magnetic activity level. Patterns of E sub s occurrence are related to concepts of the auroral oval, polar cap, and substorms. Sporadic E with top frequency = or> MHz is related to substorms. This sporadic E occurs in the late evening-early night sector of the CGL/CGT coordinate system. Implications of sporadic E on high latitude HF propagation during solar cycle maximum and minimum are discussed. (Author).