Statistical characteristics of emission occurrence are examined, using digital data of 750-Hz intensity records obtained at the conjugate pair of stations, Syowa Station in Antarctica and Husafell in Iceland. The geographic local time at Syowa and Husafell is magnetic local time plus 3 hours and minus 1 hour, respectively. The following notable diurnal variations and seasonal variations were found: (1) The emissions were mostly observed during the daytime in the conjugate region. However, the magnetic local time when the emission occurrence rate reached maximum at Husafell was 2--3 hours later than that at Syowa. (2) The seasonal variations of emission occurrence showed the same tendency at the conjugate stations. The emission intensities showed a maximum during local summer and a minimum during local winter in both hemispheres. The ratio of average emission intensity in each season to the intensity in winter is approximately 2.1--2.2 for summer, 1.7--1.9 for autumn, and 1.7 for spring. From these statistical characteristics, ELF emission intensity strongly depends on not only magnetic local time but also geographic local time and seasons, suggesting that ELF emissions observed on the ground are strongly controlled by the sunlight eflects. The sunlight may affect the asymmetry of wave duct enhancement and wave propagation from the magnetosphere to the ionosphere in both hemispheres. Other effects are also discussed in this paper. ¿American Geophysical Union 1987