The seasonal distribution of sporadic E layers observed from radio occultation measurements and its relation with wind shear measured by TIMED/TIDI

By using the 2002-2016 dataset of COSMIC, CHAMP and GRACE radio occultation (RO) and TIMED/TIDI, we investigate the morphology of global sporadic E (ES) layers and its relation with wind shear. The occurrence rate of ES layers depends on temporal and spatial variation. The occurrence rate of ES layers has a maximum at around 103 km in middle latitude regions in summer hemisphere. The results show that the global distribution of ES layers is relatively consistent with the wind shear distribution. The height-local time distribution of ES layers occurrences are primary modulated by diurnal and semidiurnal atmospheric tides. However, the distribution of ES layers occurrence rate cannot be explained completely according to the wind shear theory, especially at equatorial and auroral regions. More observations are required to further investigate the formation of ES layers and its relation with wind shear.