Study of Diurnal, Seasonal and Annual Variations in the Cosmic Radio Noise Absorption at 30 MHz in the Australian Antarctic Research Stations

Riometer is equipment used to study the cosmic noise absorption (CNA) by the ionosphere. All the observations were made using riometer with dual dipole antenna system installed at Australian Antarctic divisions. These kinds of measurements are useful to determine the absorption in the D region of ionosphere. This paper is concerned with the study of diurnal, seasonal and annual variations in the absorption of cosmic radio noise at 30 MHz. In this study we have observed the effect of solar activity on the average absorption value. Additionally, an increment in the start level of absorption of different seasons with different years has been found.