Spread F-layer echoes and radio-star scintillation

Abstract

Observations of radio-star scintillations made at University College of the Gold Coast, Achimota, and spread F-layers made at University College, Ibadan, Nigeria, have been compared. Considerable correlation is found, although there is 510 km between the two stations, and the ionospheric observations are made entirely at vertical incidence. The diurnal and seasonal variations of the presence of spread F-layers are examined. It is found that these depend considerably on the degree of magnetic disturbance. In particular, at Ibadan in winter on disturbed days there is only a quarter of the scatter that occurs on quiet days.